Tesi: "Time-lag" – Grafiati

1

Lundberg, Malin. "Lag Time: Skillnader mellan erfarna och oerfarna tolkar?" Thesis, Stockholms universitet, Tolk- och översättarinstitutet, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-133629.

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Detta är en studie som undersökt om det går att kartlägga någon skillnad mellan erfarna och oerfarna tolkar när det gäller deras lag time (eftersläpning). Lag time är tidsspannet från det att tolken hör talarens yttrande till dess att tolken själv producerar motsvarande yttrande. Tidigare forskare (t ex Cokely, 1992 och McDermid, 2014) har sett att detta påverkar resultatet av tolkningen och därför är detta intressant att undersöka närmare utifrån ett erfarenhetsperspektiv. I studien spelades tre erfarna och tre oerfarna tolkar in när de tolkade ett delvis förskrivet rollspel. Efter inspelningen analyserades materialet genom att i olika segment kontrollera med tidtagarur hur långt efter talaren tolken producerade ett yttrande liknande originaltalets. Resultatet visade att det inte var någon genomgående större skillnad mellan erfarna och oerfarna tolkar i deras lag time. I denna grupp var det istället individuella variationer. Däremot upptäcktes det att det är svårt att identifiera hur man definierar och mäter lag time.
This is a study which explored the possibility to map a difference between experienced and inexperienced interpreters in their use of lag time. Lag time is the time difference from when the interpreter hears an utterance until the interpreter him/herself starts producing an equivalent utterance. Earlier researchers (for example Cokely, 1992 and McDermid, 2014) have found that this affects the result of the interpretation and that is why this is interesting to explore from a perspective of interpreting experience. In this study three inexperienced interpreters and three experienced interpreters were recorded during a partly scripted role play. After the recording, the material was analyzed by using a stop watch to see how far behind the interpreter’s utterance was produced after the speaker’s utterance in different segments. The result showed that it was not a general difference between the experienced and inexperienced interpreters in their lag time, instead there were individual differences. What was also found is that it is difficult to identify how to define and measure lag time.

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Sarishvili, Alex. "Neural network based lag selection for multivariate time series". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=966609611.

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3

Wu, Ying. "The lag time of individual bacterial cells (Listeria monocytogenes)". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/MQ55729.pdf.

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4

John, Paul Opara, e Raymond Tarabay. "Time is Money! Time lag management in Business-IT Strategy : Emprical Validation of Theories". Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Informatik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16200.

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For today's organizations to fully optimize their two major priorities;which are reducing cost and increasing revenue, they need to be involved in continuous modifications and constant renewals of right mechanism towards alignment between business and IT strategies. This paper investigates issues in strategic alignment, the specifics were: What causes time lag between business-IT strategy implementation, how can organization manage this time lag better, and finally how alignment can be achieved in business-IT strategy. Thorough literature review has been carried out, to come up with causes of time lag between business-IT strategy. Then, two case studies together with three experts' interviews have been conducted in order to validate causes of time lag in business-IT strategy. The results shows that, lack of understanding of IT departments by business department, and lack of understanding of business department by IT department and protocol rigidity are the major causes of time lag that exists between business-IT strategy. While, the lesser factors were: not using the IT departments in defining the business strategy and usage of business terminologies by business department in communicating with the IT department

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5

Gurian, Sanford. "Resonance Compensation of Large AC Drivetrains with Significant Time Lag". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31061.

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AC main drives, such as cycloconverters, offer the possibility of higher speed and torque response over their DC counterparts. The price to be paid, however, is torque ripple which is a function of the operating frequency. Even a small value of ripple, at an underdamped plant resonant frequency, may be multiplied by the plant "Q" to a large enough value to cause trouble. Typical classical approaches used in the rolling mill industry to deal with mechanical resonance tend to fall apart with large values of time lag. We investigate a modified LQR/LQE approach using a torque sensor as the feedback element. The result is a low order SISO filter that suppresses the effects of the torque ripple on the underdamped plant.
Master of Science

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Simas, Maria Joao Correia de 1966. "Lag-time characteristics in small watersheds in the United States". Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282155.

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Time is an important element in hydrologic design. Most hydrologic models require a watershed characteristic that reflects the timing of runoff. The time parameter used in this study was lag time, defined as the time from the centroid of rainfall excess to the centroid of direct runoff. Lag times were evaluated from rainfall-runoff data in over 40,000 events in 116 small watersheds in the United States. The watersheds ranged from 0.243 to 3490 acres, with periods of rainfall-runoff records from 3 to 58 years. Rainfall-runoff event characteristics were used to determine a unique value of lag time for each storm. A tendency towards a constant value of lag time for the "bigger" storms was observed, "bigger" meaning higher values of either previous 48-hour rainfall, average effective rainfall intensity, average runoff intensity, or peak flow. The variable peak flow best showed this tendency; higher peak flow was associated with constant lag time in over 90% of the watersheds. Several hydrologic relationships involving lag time previously described in the literature were not verified in this study. Watershed characteristics were evaluated as "predictors" of lag time within a given watershed. The geomorphic variables used were area, length, width, slope, and storage coefficient (Curve Number). All variables were significant in explaining the variation of lag time by the regression analysis. The watersheds were divided into groups to try to explain the variation of lag time between watersheds. Management practices, geographical region, and the tendency toward constant value of lag time for the "bigger" storms had significant effects in the regression analyses, whereas land use and hydrologic behavior did not. When only the watersheds with the tendency described above were used, no groupings significantly improved the regression equations. Rainfall-runoff data should be used to compute lag time directly, especially for the bigger storms. If data are insufficient, regression predictions can be improved by grouping watersheds by regions and management practices. Width, slope and Snat are the best variables for prediction of lag time. The multiple linear regression model developed in this study had a higher coefficient of determination than other models in the literature.

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Shively, Matthew David. "Spacing and Lag Effects in Recognition Memory: Time Versus Intervening Items". Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/shively/ShivelyM0507.pdf.

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Spacing and lag effects both refer to abundant findings that memory is enhanced when repeated items are spaced. Several researchers have realized the difficulty of explaining these effects using only one theory, and, therefore posited varying dual-process models. It is also unclear if there is a limit to the increase in memory performance due to increased lag. This study sought to understand how stimulus type influences spacing and lag effects, limits of the lag effect, and the importance of time and items in creating these effects. Experiment 1 found a unique spacing effect and lag effect. Experiment 2 found no spacing effect, yet a lag effect was found. Both time and items are important in generating spacing and lag effects.

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8

Johns, Alicia. "Methods for Estimating the Optimal Time Lag in Longitudinal Mediation Analysis". VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6042.

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Interest in mediation analysis has increased over time, with particular excitement in the social and behavioral sciences. A mediator is defined as an intermediate in the causal sequence between an independent and dependent variable. Previous research has demonstrated that the cross-sectional form of mediation analysis is inherently flawed, evidenced by the inability of the cross-sectional mediation model to account for temporal precedence and estimation of the indirect effect being biased in nearly all situations. For these reasons, a longitudinal model is recommended. However, a method for determining the exact time points to measure the variables used in mediation analysis has not been adequately examined. In this study, we examined methods for determining an appropriate time lag when designing a mediation study. The methods implemented include correlation analysis, the quadratic and exponential forms of the lag as a moderator approach, and knot estimation using basis splines. The data for the study was simulated for three distinct trends generated using a linear piecewise model, a sigmoid model, and a sigmoid piecewise model. Additionally, two sampling approaches, an intense sampling approach and a three-measure approach, were examined as well as six sample sizes and three effect sizes for the total effect on the outcome. The estimation methods were additionally compared by considering different types of error structures used in data generation as well as by examining equal and unequal time lag lengths between the predictor and mediator, and the mediator and outcome. The intent of the study is to provide methods so that researchers can estimate the best time to evaluate mediator and outcome measurements that will be used in mediation analysis. The results from this study showed that the best estimation method varied depending on the lag being estimated, the sampling approach, and the length of the lag. However, the knot estimation approach worked reasonably well in most scenarios considered even with small sample sizes of 5 or 10 per group. The findings from this study have the potential to improve study design for research implementing longitudinal mediation analysis by reducing bias in the estimate of the indirect effect when adequate time points are used.

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Wang, Shuye. "Asymmetric lead-lag relation, nonsynchronous trading, time-varying risk premium, and cointegration". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35984.pdf.

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10

Garcia, Mendoza Jesus Guillermo. "Lag Time Characteristics of Small Arid and Semiarid Watersheds in the Southwestern United States". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/311345.

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An evaluation for Lag time, defined as the time from the centroid of rainfall excess to the centroid of direct runoff, was performed for seven small watersheds in the Southwestern United States. The size of these watersheds range in size from 0.33 to 4.37 ha. The evaluation period goes from 2000 to 2010. This evaluation was compared versus 28 lag time equations.The USDA-ARS Southwest Watershed Research Center has developed an electronic data processing system where rainfall and runoff data is collected from sensors in the field and are transmitted to computers in the office.Prior to these data sets there were no measurable rainfall and runoff data. This digital data is generated by means of synchronized clocks in rain gages and flumes. As a result, the data from this electronic processing system offers a unique opportunity for hydrologic research. This infrastructure is a characteristic not often available in many other sites and a condition not enjoyed in previous investigations.There are several definitions of lag time depending on what particular time period is used to describe the occurrence of unit rainfall and runoff. But, time parameters currently lack commonly-accepted standard definitions.The various definitions for time parameters such as Lag Time, Time of Concentration, Time to Peak, Equilibrium Time and others, sometimes, are used interchangeably. Another aspect is that in Lag time determination, centers of mass play a critical role. This study found out that depending of the loss model chosen to estimate rainfall excess, it shall influence the determination of center of mass and hence the lag time.Some negative values were obtained for lag time when measured from peak of runoff to centroid of effective rainfall. However, in the lag time definition from centroid of effective rainfall to centroid of direct runoff, negative values were not obtained.One field in particular, time parameters currently lacks commonly-accepted standard definitions. This has become a source of profound confusion in this branch of science to the point where teams of scientists writing about and discussing hydrological Time Parameters can be compared to the aftermath at the Tower of Babel.

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Jovanovska, Delfina. "Scheduling Time-Sensitive Tasks using a Combination of Proportional-Share and Priority Scheduling Algorithms". Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1300244698.

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12

Wu, Haoyu. "Gas Membrane Characterization Via the Time-Lag Method for Neat and Mixed-Matrix Membranes". Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/41226.

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Separation technologies with polymeric membranes are widely studied and have a wide range of applications. The membrane's heart is a dense selective layer whose permeability should strongly depend on the permeating species' properties. In turn, permeability depends on the diffusivity and solubility of the permeating species in the selective layer, which are considered intrinsic properties of the polymer forming the selective layer. When developing new membrane materials, the ultimate objective is to exceed the famous "upper bound" limit by achieving simultaneously higher selectivity and higher permeability. This objective is impossible without a reliable and accurate characterization method to determine the selective layer's intrinsic transport properties. The time-lag method is the most common membrane characterization technique, initially developed for polymeric membranes. However, as the membrane technology and material science advance, the selective layer structure becomes more complex and not limited to organic polymers. As a result, the time-lag method needs to be reviewed and adapted to these more complicated cases, which was the main objective of this thesis. Numerical simulation of dynamic gas permeation experiments is a powerful tool to examine different aspects of the time-lag method. Therefore, we have established a comprehensive variable-mesh finite-difference scheme, which was used throughout the thesis. It allowed us to investigate the effect of different random and resolution errors and an extrapolation error on the resulting time lag of an ideal membrane. We then considered more complex systems, particularly those of glassy polymers and mixed matrix membranes, to investigate the effect of different transport mechanisms on the results of dynamic and steady-state gas permeation experiments. In parallel, we also focused on developing a novel gas permeation system that would monitor dynamic gas permeation experiments based on pressure decay at the feed side. All the existing constant-volume gas permeation systems rely on monitoring pressure to rise at the membrane's permeate side. Although this work is still ongoing, we have made considerable progress. Among the numerous contributions made through this thesis, there are three of particular significance. We have developed an analytical model to predict mixed matrix membranes' relative permeability with the uniformly dispersed non-permeable fillers of different shapes. The model requires three structural parameters arising from the filler's shape and size, and it is superior to all existing analytical models, including the famous Maxwell model. We have also demonstrated that the diffusivity of mixed matrix membranes determined by the time-lag method depends on the number of layers of dispersed particles. In the limiting case of a single layer of uniformly impermeable fillers, it is possible for the diffusivity determined by the time-lag method to be greater than that of the host polymer, which might appear as counterintuitive in the absence of defects at the polymer-particle interface. In the case of glassy polymers, it is possible to observe an upward deviation from the steady-state flux, resulting from a non-instantaneous equilibrium between permeating species in Henry's and Langmuir adsorption sites.

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Kim, Doo Young. "Statistical Modeling of Carbon Dioxide and Cluster Analysis of Time Dependent Information: Lag Target Time Series Clustering, Multi-Factor Time Series Clustering, and Multi-Level Time Series Clustering". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6277.

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The current study consists of three major parts. Statistical modeling, the connection between statistical modeling and cluster analysis, and proposing new methods to cluster time dependent information. First, we perform a statistical modeling of the Carbon Dioxide (CO2) emission in South Korea in order to identify the attributable variables including interaction effects. One of the hot issues in the earth in 21st century is Global warming which is caused by the marriage between atmospheric temperature and CO2 in the atmosphere. When we confront this global problem, we first need to verify what causes the problem then we can find out how to solve the problem. Thereby, we find and rank the attributable variables and their interactions based on their semipartial correlation and compare our findings with the results from the United States and European Union. This comparison shows that the number one contributing variable in South Korea and the United States is Liquid Fuels while it is the number 8 ranked in EU. This comparison provides the evidence to support regional policies and not global, to control CO2 in an optimal level in our atmosphere. Second, we study regional behavior of the atmospheric CO2 in the United States. Utilizing the longitudinal transitional modeling scheme, we calculate transitional probabilities based on effects from five end-use sectors that produce most of the CO2 in our atmosphere, that is, the commercial sector, electric power sector, industrial sector, residential sector, and the transportation sector. Then, using those transitional probabilities we perform a hierarchical clustering procedure to classify the regions with similar characteristics based on nine US climate regions. This study suggests that our elected officials can proceed to legislate regional policies by end-use sectors in order to maintain the optimal level of the atmospheric CO2 which is required by global consensus. Third, we propose new methods to cluster time dependent information. It is almost impossible to find data that are not time dependent among floods of information that we have nowadays, and it needs not to emphasize the importance of data mining of the time dependent information. The first method we propose is called “Lag Target Time Series Clustering (LTTC)” which identifies actual level of time dependencies among clustering objects. The second method we propose is the “Multi-Factor Time Series Clustering (MFTC)” which allows us to consider the distance in multi-dimensional space by including multiple information at a time. The last method we propose is the “Multi-Level Time Series Clustering (MLTC)” which is especially important when you have short term varying time series responses to cluster. That is, we extract only pure lag effect from LTTC. The new methods that we propose give excellent results when applied to time dependent clustering. Finally, we develop appropriate algorithm driven by the analytical structure of the proposed methods to cluster financial information of the ten business sectors of the N.Y. Stock Exchange. We used in our clustering scheme 497 stocks that constitute the S&P 500 stocks. We illustrated the usefulness of the subject study by structuring diversified financial portfolio.

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Gavriilidis, Nikolaos. "Time series analysis of the lead-lag relationship of freight futures and spot market prices". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46067.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.
"September 2008."
Includes bibliographical references (p. 96).
This thesis analyzes the relationship between the physical and paper shipping markets. The main objective is to find if one market leads the other by a specific time period so that market players can take advantage from that. Three different methods were used to analyze this relationship. The first is a rolling average technique to smooth the strong fluctuations of the market and plot the relevant graphs. From there we can have a first look on whether there is a lead-lag relationship between the two markets. The second method was the cross-correlation function which allows us to time shift back and forth the two time series in order to compare the relevant correlation coefficients. In the third method, a Vector Error Correction model was created for each pair of time series in order to test the influence of the one series to the other. Finally, we present a brief comparison between the volatility of the freight rates and the trading value of freight futures so we can judge if the spot market became more volatile with the growth of trading of freight futures.
by Nikolaos Gavriilidis.
S.M.

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Mikkelsen, Markus, e Gustav Svanfors. "Mätning av LCD-bildskärmars responstid och latens : Measurement of LCD displays response time and input lag". Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26555.

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Examensarbetet har utförts i samarbete med företaget LVI (Low Vision International) som tillverkar elektroniska hjälpmedel för synskadade. LVI utvärderar vid jämna mellanrum nya LCD-bildskärmar för deras produkter. LVI behöver metoder samt utrustning för att mäta bildskärmars responstid och latens. Både responstiden och latensen ger fördröjningar vilket t.ex. leder till att bilden blir oskarp, rörliga föremål får en svans efter sig eller att lju- det kommer före bilden. I detta arbete utförs en grundlig förstudie som behandlar bild- skärmars responstid och latens samt ger ett underlag för att konstruera eller köpa mätut- rustning för responstidsmätningar. I förstudien framkommer den standardiserade mätmeto- den ”grey-to-grey” som LVI kan använda för att mäta responstiden. En mätkrets konstrue- ras för att mäta responstiden samt beställs en dedikerad enhet för latensmätning. För att ut- värdera mätmetoderna utförs ett antal tester med mätkretsen för responstid och den dedike- rade enheten för mätning av latens. Mätningarna visar senare att mätmetoden ”grey-to- grey” är den som LVI ska använda men metoden behöver vidareutvecklas. Den dedikerade enheten för latensmätningar visar sig mäta en del av responstiden och bör därför endast an- vändas som komplement till responstidsmätningen vid jämförelser mellan olika bildskär- mar. Arbetet levererar en förstudie i LCD-bildskärmars responstid och latens, en vidareut- vecklad version av ”grey-to-grey”-metoden, mätutrustning för responstidsmätning samt den dedikerade mätenheten för latens till företaget LVI.
The thesis was performed in collaboration with the company LVI (Low Vision Interna- tional) that manufactures electronic devices for the visually impaired. LVI evaluates new LCD displays for their products at regular intervals. LVI need methods and equipment for measuring response time and input lag. Both response time and input lag cause delays, which results in such things as image blur, ghosting after moving objects or a delay between sound and image. The preliminary study reveals the standardized method “grey- to-grey” that LVI can use to measure response time. A measurement circuit was constructed to measure response time and a dedicated unit for input lag measurement was ordered. To evaluate the measurement methods a number of tests were conducted with the response time circuit and the dedicated input lag unit. The measurements showed that the method LVI shall use is the "grey-to-grey” method but it needs further development. It turned out that the dedicated unit for input lag measured a portion of the response time and should therefore only be used as a complement to the response time measurement when comparing displays. The thesis delivers a preliminary study in LCD displays response times and input lag, a further developed version of the “grey-to-grey” method, measurement equipment for response time and a dedicated unit for input lag measurements to the company LVI.

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Potgieter, Dorathea Maria. "Constraints experienced in managing Triple Helix in South Africa / Doret Potgieter". Thesis, North-West University, 2012. http://hdl.handle.net/10394/9819.

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Rapid changes in the global economy forces Industry to continuously seek competitive advantages; the University on the other hand pursue additional funding. Both Industry and University are trying to keep up with the accelerating pace of change, therefore partnership become critical in achieving key objectives. Research collaborations become essential and offer direct benefits for University and company participants. The impact extends well beyond the direct partners. When potential partners have the resources and knowledge to accomplish individual goals, working with outside experts can improve the quality of the research and help to reduce costs. Industry-sponsored research allows the University to obtain financial support as well as Industry exposure for its educational and research missions. The Technology and Human Resources for Industry Programme (THRIP) aims to boost South African Industry by supporting research and technology development, and by enhancing the quality and quantity of appropriately skilled people. THRIP brings together the best of South Africa's researchers, academics and industry players in funding partnerships that enable participants to improve the quality of their products, services and people. In 13 years it has become a powerful formula for stimulating innovation in South Africa - innovation leads to competitiveness and competition leads to growth. There are many difficulties in managing projects across organisational boundaries; their cultures and their mission differ. The goal and the prime objective of the industries are to make a profit and build-value for shareholders. The universities‟ missions are to develop new knowledge and educate the next generation. Factors that may prevent research collaboration with Industry from being successfully accomplished are: • The practical difficulties of managing a collaboration, • Deleterious effects on faculty and students, • Impact on the mission, • Reputation and financing of the University. Industry needs to overcome the following hurdles in order to foster greater collaboration: • Respect the value of research collaboration, • Incorporate University research into product development, • Management barriers.
Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

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Bender, Andreas [Verfasser], e Helmut [Akademischer Betreuer] Küchenhoff. "Flexible modeling of time-to-event data and exposure-lag-response associations / Andreas Bender ; Betreuer: Helmut Küchenhoff". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1164377485/34.

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Tan, Yubo. "A Comparison of Methods for Addressing Lag Uncertainty in Cumulative Exposure-Response Analyses for Time-to-Event Data". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492560510005231.

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19

VERA, PHUNG LING HUI. "New perspectives in epidemiological studies on health effects of atmospheric particles : Time lag, duration and intensity of exposure". Kyoto University, 2019. http://hdl.handle.net/2433/244541.

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20

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process". School of Biological Sciences. University of Sydney, 2008. http://hdl.handle.net/2123/2761.

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Doctor of Philosophy (PhD)
Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.

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21

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process". Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2761.

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Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.

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22

Junior, Hamilton Haddad. "O efeito modulatório de ações motoras em latências perceptivas visuais". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-16032009-133451/.

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Abstract (sommario):

Organismos são capazes de diferenciar estímulos sensoriais gerados independentemente pelo ambiente dos estímulos causados por sua própria ação no mundo. Esse processo depende de mecanismos neurais e cognitivos que unam suas ações às percepções por elas geradas. Objetivo desse trabalho foi investigar a interação da ação com a percepção visual no domínio temporal. Em cinco experimentos psicofísicos, foi estudado o efeito modulatório da ação no efeito flash-lag e em tarefas envolvendo estimativas de intervalos temporais. Nossos resultados mostraram que o planejamento e/ou execução de atos motores voluntários são capazes de reduzir em algumas dezenas de milissegundos as latências com que estímulos visuais são percebidos e também de reduzir as estimativas de intervalos temporais. A redução dessas latências é maior quando a conseqüência sensorial da ação é apresentada na fóvea, assim como quando existe um atraso entre a ação e o estímulo por ela causado.
Organisms are able to distinguish between sensory stimuli from the environment and sensory stimuli they cause. This process depends on neural and cognitive mechanisms that link actions to perceptions generated by these actions. This work aimed to investigate the interaction of action and perception in the temporal domain. In five psychophysical experiments, we have assessed the modulation of action in the flash-lag effect and in tasks involving temporal interval estimations. Our results showed that the planning and execution of a voluntary motor action are capable of reducing both visual perceptual latencies and temporal interval estimations. This reduction increases when the sensory consequences of motor actions are presented on the fovea and when a delay is injected between the action and the stimuli caused by it.

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23

Spencer, John M. "Comparing a low-volume piezometer to traditional wells in evaluating hydraulic lag caused by low-permeability sediments". [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002435.

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24

Wang, Lei. "Cyclic membrane gas separation processes". Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0291/document.

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Ce travail traite une investigation systématique des performances du procédé membranaire cyclique par séparation gazeuse. Premièrement, l'état de l'art du procédé membranaire cyclique, les problèmes techniques et la modélisation du transfert à travers la membrane ont été exposés. Deuxièmement, les études théoriques et expérimentales existantes sur le procédé cyclique sont passées en revue. Selon la durée de pression haute et sa fraction dans un cycle, ce genre d'opération est divisé en deux classes: classes courte et longue. D'après cette classification, une analyse systématique de l'intérêt potentiel de la classe courte par rapport aux performances d'une opération en régime permanent a été accomplie par des simulations et optimisations numériques. Par ailleurs, afin d'améliorer la performance, l'usage du MMM dans un tel procédé a été discuté. En parallèle à l'étude sur la classe courte, une nouvelle conception du procédé cyclique de classe longue a été proposée. Les avantages spectaculaires par rapport aux procédés membranaires classiques ont été mis en évidence à l'aide de nos simulations et optimisations. Finalement, une validation expérimentale a été effectuée afin de fournir un support solide à cette nouvelle conception
This study deals with a systematic investigation of the performance of cyclic membrane gas separation processes. First, a state of the art of membrane separation processes, including material challenges and mass transfer modeling issues is proposed. In a second step, a review of the different theoretical and experimental studies performed on cyclic processes is reported. With respect to the length of the high pressure stage and its fraction in one cycle, these operations are classified into short and long classes. Based on this classification, a systematic analysis of the potential interest of short class compared to steady-state operation performances has been achieved by means of numerical simulation and optimization. In order to improve the performance, the use of MMM in such a process has been further discussed. In parallel with the short class study, a design of novel long class has been proposed. Spectacular advantages with respect to classical membrane-based processes have been highlighted by means of our simulation and optimization studies. Finally, an experimental verification has been performed in order to provide a solid support to this novel process

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25

Zhou, Xin. "Robust Reputation System for Web Services". 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/217204.

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26

Al-Ismaily, Mukhtar. "A Novel Method of Characterizing Polymer Membranes Using Upstream Gas Permeation Tests". Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20463.

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Abstract (sommario):

Characterization of semi-permeable films promotes the systematic selection of membranes and process design. When acquiring the diffusive and sorption properties of gas transport in non-porous membranes, the time lag method is considered the conventional method of characterization. The time lag method involves monitoring the transient accumulation of species due to permeation on a fixed volume present in a downstream reservoir. In the thesis at hand, an alternative approach to the time lag technique is proposed, termed as the short cut method. The short cut method appoints the use of a two reservoir system, where the species decay in the upstream face of the membrane is monitored, in combination with the accumulation on the downstream end. The early and short time determination of membrane properties is done by monitoring the inflow and outflow flux profiles, including their respective analytical formulas. The newly proposed method was revealed to have estimated the properties at 1/10 the required time it takes for the classical time lag method, which also includes a better abidance to the required boundary conditions. A novel design of the upstream reservoir, consisting of a reference and working volume, is revealed, which includes instructional use, and the mechanics involved with its operation. Transient pressure decay profiles are successfully obtained when the reference and working volumes consisted of only tubing. However when tanks were included in the volumes, large errors in the decay were observed, in particular due to a non-instantaneous equilibration of the pressure during the start up. This hypothesis was further re-enforced by examining different upstream tank-based configurations. iii In the end, a validated numerical model was constructed for the purpose of simulating the two reservoir gas permeation system. A modified form of the finite differences scheme is utilized, in order to account for a concentration-dependent diffusivity of penetrants within the membrane. Permeation behavior in a composite membrane system was disclosed, which provided a new perspective in analyzing the errors associated with the practical aspect of the system.

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27

Hackett, Stacey Lynn. "Improving administrative operations for better client service and appointment keeping in a medical/behavioral services clinic". Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc9099/.

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Abstract (sommario):

Appointment no-shows are a problem in healthcare organizations. It is important that appointment intake and scheduling processes are effective in both meeting client needs and efficient in meeting organizational business requirements. This study examined baseline levels of appointment keeping in a not-for-profit medical/behavioral pediatric services clinic, analyzed existing administrative processes, introduced additional appointment keeping reminders, and presented systematic, performance management tutorials for clinic employees. Results indicate an increase in percentage of appointments kept and a decrease in appointment lag time.

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28

Owaisat, Suzan. "A novel oral dosage form with drug independent formulation and variable controlled release". Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/342831.

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Abstract (sommario):

Pharmaceutical Sciences
Ph.D.
A unique dosage form which uses a hydrophilic polymer was developed to provide for a predicable release of several drugs. This drug release could be optimized for controlled release using erosion. It can also be designed to release drug utilizing electrochemical processes. The accuracy of drug delivery in terms of dose and timing is of utmost importance for the patient’s health status and compliance. A well-designed drug delivery technology offers many advantages to the patient. These advantages include: reduction in dose frequency, reduction of drug side effects, reduced unwanted fluctuations in circulating drug levels, and a more uniform effect of the drug over time. The practice of drug delivery has been dramatically developed in the last decade including electronic controlled release innovative dosage forms. In this study the iontophoretic flux of ibuprofen was investigated using side- by-side diffusion cells. Iontophoresis is the process where electric current is applied to enhance transportation of drugs across the skin. The pH change was found to be an important factor in increasing the diffusion of the drug. The principle of using electric current as a driving force to control the drug release was initially demonstrated on an initial setup. Subsequently, a calcium binding polymer was the hydrogel used as a matrix to develop a new electric oral dosage form. The calcium binding polymer is produced in different forms. The production process of these forms suffers several limitations. In order to apply electric current in a practical way to the calcium binding polymer matrix a novel method was developed. The novel method also allowed for addressing the limitations related to the production process of the conventional dosage form made with this polymer. More uniform gel tablets in shape and size were produced. Different formulations were developed. Ibuprofen was the model drug initially used to investigate the factors that affected the release profiles of these tablets. A two-level, three-factor statistical design of experiments (DOE) was performed to evaluate the effect of those factors on certain responses. These responses included the release rate, time needed to release 80% of the model drug, and lag-time. A new formulation with certain adjuvants was developed. This formulation had the ability to release different kinds of drugs in a uniform release rate. A fail-safe tablet that can only release less than 20% of the drug in 24 hours was developed. The drug release was initiated only when the electric current was applied. This new electric dosage form was aimed to overcome the disadvantages related to conventional dosage forms such as the inability to supply drugs on demand.
Temple University--Theses

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29

Krampell, Martin. "About time : Temporality in interaction". Thesis, Linköpings universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-108353.

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Ever since the inception of the modern computer, researchers and designers alike have been interested in the effects of system delays on users. The current study was conducted in order to examine the most central issues to the field of temporality in interaction, and presents a consolidation of a selection of publications on the subject. A distinction between two types of interactive systems, discretionary and continuous, is proposed in order to situate previous studies by the system being studied. The type of control being exerted by users differs on a fundamental level between the two types, hence affecting the effects of delays. Furthermore, an experiment was conducted to examine the effects of constant, sub-second system delays in discretionary tasks using a digitalised version of the Trail Making Test (FR-TMT, Summala et al., 2008). The experiment yielded but one significant result in form of an improvement in user response time as delays were increased. The other results showed no significant positive or negative effect of increased delays. These results are indicative that the chosen delays do not have any detrimental effects on users, in accordance with the presently coined ’theory of task interruption’. This theory considers delays as either interruptive or non-interruptive and maintains that only delays that disrupt user work-flow are to be removed from interactive systems. The current study gives reason to why some delays can be positive to user interaction, or in themselves be informative of system status, and be an integral part of a feedback structure. Further research is needed before all aspects of system delays are fully understood. New ways of looking at delays and using them in system design, like predictability and predictivity, are becoming more prevalent, and may become the focus of research and temporal design in the near future.

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30

Zengshiting, Zhang. "Detecting and resolving work-space conges-tions and time-space conflicts through 4D - Modeling in the Micro level". Thesis, KTH, Fastigheter och byggande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183101.

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Abstract (sommario):

This degree project aims to find solutions to prevent construction process from delay by detecting and resolving work-space congestions and time-space conflicts based on 4D-modeling. The purpose is to improve the work efficiency on the construction site of a hospital project. Through a software experiment, the proposed solutions will be tested to see if the conflicts on the construction site can be resolved or minimized. This is achieved by following the construction phase of the NKS project from Skanska AB. The largest hospital project in Sweden. The theoretical framework focuses on the concepts of 4D, work-space congestions, time-space conflicts, lean construction, last planner system, project organization as well as reviewing a variety of literature regarding how to resolve the conflicts during the construction process. The useful data and information have been gathered through semi-structured interviews with project managers and workforce. The obser-vations have been done on-site. Followed by 4D software experiment, by associating the tasks to the different areas through LBS with the time constraint data, the effi-ciency of work based on the quantity takeoff can be evaluated and thus it allows pro-ject managers to foresee the potential conflicts easily. Eventually, applying 4D - modeling helps the planners visualize the inefficiencies in the schedule and thus re-schedule the tasks before they lead to delays.
Syftet med detta examensarbete är att finna lösningar för att förhindra konstruktions-processen från förseningar genom att upptäcka och lösa arbetsplatsstörningar samt tids- och utrymmeskonflikter baserat på 4D-modelering. Målet är att effektivisera arbetet på byggarbetsplatsen för ett sjukhusprojekt. Genom simuleringar kommer föreslagna lösningar, för att undvika konflikter på arbetsplatsen, att prövas för att få bukt med eller minimera dessa konflikter. Detta uppnås genom att följa byggnadsfasen av NKS-projektet från Skanska AB. Sveriges största sjukhuspro-jekt. Den teoretiska referensramen fokuserar på begreppen: 4D, arbetsutrymmesbelast-ning, tids- och platskonflikt, lean construction, last planner-systemet, projektorgani-sation samt granskning av litteratur som handlar om konfliktlösning under byggpro-cessen. Användbara data och information har samlats in via semistrukturerade inter-vjuer med projektledare och byggnadsarbetare. Observationer har gjorts på plats. Följt av 4D-simulering, genom att sammankoppla uppgifter till de olika områdena ge-nom LBS med tidsrestriktionsdata, kan effektiviteten av arbete som bygger på mängdavtagning utvärderas. Det tillåter projektledare att utan svårighet förutse po-tentiella konflikter. Så småningom kan tillämpningen av 4D-modellering hjälpa plane-rare att visualisera ineffektiviteter i tidsplanen och därmed planera om arbetsuppgif-terna innan de leder till förseningar.

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31

Liu, Xiaoli. "Spatial Correlation Study on Hybrid Electric Vehicle Adoption". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397646595.

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32

Xu, Yizhi. "Aspects of modelling variability of single cell lag time for Cronobacter spp. after exposure to sublethal heat treatment in normal and stressful environments". Thesis, London Metropolitan University, 2014. http://repository.londonmet.ac.uk/1212/.

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Abstract (sommario):

The growth profiles of five strains of Cronobacter spp. at low temperature (4 oC to 8 oC) and their thermal resistance to mild heat treatment (48 oC to 50 oC) were investigated with a view to developing a model to predict lag times of individual cells, using a strain with a relatively high thermotolerance and able to grow well at refrigeration temperature (7 oC). The effect of heat stress (49 oC for 7 min) and subsequent recovery temperatures (7 oC to 22 oC) on the individual cellular lag times of one strain of Cronobacter turicensis were analysed using optical density measurements. It was found that the distribution of individual lag times of Cr. turicensis shifted right and became more spread when the recovery temperature decreased, and the distribution was more skewed after heat stress. Assuming the lag of a single cell follows a shifted Gamma distribution with a fixed shape parameter, the effect of recovery temperature on the individual lag times of untreated and sublethally heat stressed cells of Cr. turicensis were modelled. It was found that the shift parameter (Tshift) increased asymptotically as the temperature decreased, while the logarithm of the scale parameter (θ) decreased linearly as recovery temperature increased. To test the validity of the model, growth of low numbers of untreated and heat stressed Cr. turicensis in tryptone soy broth (TSB) and infant first milk was measured experimentally between 7 oC and 22 oC and compared with predictions obtained by Monte Carlo simulations. It was found that in TSB, in most cases, the simulations from both models underestimated the actual growth of individual cells of Cr. turicensis from challenge tests; while in first milk, the untreated model slightly underestimated the actual growth at low temperatures (7 oC and 12 oC). The heat stressed model in first milk was generally in agreement with the data derived from the challenge tests and provides a basis for reliable quantitative microbiological risk assessments for Cronobacter spp. in infant milk. The study has made a contribution to understanding and modelling the responses of untreated and sublethally heat stressed Cr. turicensis at 7 oC, 12 oC and 22 oC at single cell level.

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33

Shemshaki, Farzaneh. "Prediction of time lag in vacuum tubes and its implications for characterization of membranes in constant volume systems: Effect of resistance-free accumulation tank". Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/27036.

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Abstract (sommario):

In this project a "time limitation" of the previous analysis has been overcome by allowing the diffusion coefficient downstream from the tested medium to vary with pressure, describing this relationship using the empirical model of Knudsen. This required a numerical solution of the governing partial differential equation, which has been done by applying a finite difference scheme. The theoretically obtained pressure responses have been compared with the experimental pressure responses in two different flow cases, a constant flow and a time-dependent flow at a tube entrance. The former case was realized by using a low-flow mass flow controller as a flow source. The latter case was realized by using a homogeneous polymeric film, whose one side was instantaneously pressurized in a step-wise manner (time lag technique). The theoretical model slightly underestimates the resistance effects. This has been attributed to an unavoidable presence of a dead volume in the experimental system, i.e. the volume associated with valves, pressure sensors, bypass tubes, etc. A procedure for correcting the experimentally determined transport coefficients of gas in a membrane for the resistance effects has been developed and demonstrated. (Abstract shortened by UMI.)

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34

Silva, Hozana. "Análise da temperatura do ar utilizando a teoria da complexidade em floresta de transição no norte de Mato Grosso". Universidade Federal de Mato Grosso, 2014. http://ri.ufmt.br/handle/1/675.

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Abstract (sommario):

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O objetivo do trabalho foi analisar a temperatura do ar utilizando a teoria da complexidade em floresta de transição no Norte Mato Grosso. Avaliar a relação entre os atratores reconstruídos e as estações do ano, a influência de frentes frias e posteriores variáveis que modificam os padrões da temperatura do ar. Os dados abrangem os anos 2001, 2002, 2003 e 2007, a análise estatística foi realizada com o teste de Qui-Quadrado (X2), verificando que os valores médios horários representam os dados experimentais para os meses considerados. Logo, a Floresta Amazônica tem sido considerada um importante ecossistema no controle do clima local. Com o desmatamento em grande escala, poderão se perceber mudanças no clima local. Por isso, a Teoria da Complexidade é necessária para entender a floresta amazônica por se tratar de um ambiente complexo, onde suas variáveis se influenciam mutuamente não obedecendo a uma linearidade, por consequência levando à incerteza e imprevisibilidade intrínsecas. Com essa condição, torna-se necessário um estudo que aprofunde no comportamento dos ecossistemas da Floresta Amazônica. Para um melhor entendimento da previsibilidade das variáveis ambientais com a temperatura do ar, faz-se necessário um estudo sobre essa variável em certos períodos, verificando, assim, as dificuldades em prevê-las e um possível efeito da sazonalidade. Uma maneira de conduzir esse estudo é a reconstrução de atratores, tendo como base a Teoria da Complexidade.
The aim of study was to study the air temperature behavior using complexity theory in transition forest in Sinop Mato Grosso State. Evaluate the relationship between the attractors reconstructed and the seasons, influence of cold fronts and subsequent variables that modify the patterns of air temperature. The data include the years 2001, 2002, 2003 and 2007. The statistical analysis was performed with chi - square test (x2) checking the hourly average values represent the experimental data for months. Soon the Amazon rainforest has been considered important ecosystem in control of the local climate. With the large-scale deforestation, may notice changes in the local climate. Therefore, Complexity Theory is needed to understand the Amazon rainforest because it is a complex environment where your variables influence each other not obeying a linearity thus transmitting to the inherent uncertainty and unpredictability. With this condition, it is necessary a study more dup that this ecosystems behavior of the Amazon rainforest. For a better understanding of the environmental variables predictability, likes air temperature, it is necessary a study of this variable in certain periods, thus verifying the difficulties in providing for them and a possible effect of seasonality. One way to conduct this study is the reconstruction of attractors, based on the Theory of Complexity.

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35

Ciuti, Sara. "L'interpretazione simultanea dall'italiano in ungherese: disfluenze ed errori derivanti dalle peculiarità della coppia di lingue". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20858/.

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The aim of this case study is to analyse the performances of two Hungarian interpreters during Simultaneous Interpreting (SI) from Italian into Hungarian. Since they provide a valuable glimpse into cognitive activity, this study is mainly focused on the analysis of disfluencies in the Hungarian interpreted text. It gives special attention to the error-type disfluencies (ETDs) and to the nature of the grammatical errors that both interpreters committed, in order to analyse their cognitive load during SI from Italian. The study thus analyses the most frequent types of disfluencies in both subjects, highlights individual differences and similarities while comparing the results with previous studies on the matter, in particular with Bakti’s (2009, 2010, 2017) and Gósy’s (2003, 2007, 2016) works, among others. The first chapter presents the hungarian language, its origins and its grammar, allowing the reader to better understand part of the analytical contents. The second chapter deals with the theoretical background that inspired this research: it first offers an overview of the cognitive load in SI presented through Gile’s Efforts Model and, in relation to the cognitive aspect, describes the time lag and the disfluencies together with the different methods of measurement and classification used by the researchers. In the third chapter I describe the material and explain the method I used to carry out this research through all its phases. The fourth chapter is split into two main sections: the first one presents the collected data for disfluencies, grammatical errors and time lag values, separately for both the interpreters; the second part combines the results obtained for these three different groups of data and discusses them, underlining the differences between the two interpreters in terms of cognitive load and expertise. It also shows the most common types of grammatical errors and provides a comparison with the results obtained in previous studies.

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36

Jansen, van Vuuren A., E. Pretorius e N. Benade. "Catchment management-model evaluation : verifying data for the implementation of the water release module of the WAS program". Interim : Interdisciplinary Journal, Vol 4, Issue 1: Central University of Technology, Free State, Bloemfontein, 2005. http://hdl.handle.net/11462/426.

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Published Article
The Water Administration System (WAS) is designed to be a management tool for irrigation schemes and water offices that want to manage their water accounts and supply to clients through canal networks, pipelines and rivers. The ultimate aim of WAS is to optimize irrigation water management and minimize management-related distribution losses in irrigation canals. This research project focus on the implementation of the water release module of the WAS program at the Vaalharts irrigation scheme. WAS consists of four modules that are integrated into a single program that can be used on a single PC, a PC network system (in use currently at Vaalharts) or a multi-user environment. These modules can be implemented partially or as a whole, depending on the requirements of the specific scheme or office. The four modules are an administration module, a water request module; water accounts module and a water release module. The first three modules are already implemented at Vaalharts, while module four is implemented only partially. This module links with the water request module and calculates water releases for the main canal and all its branches allowing for lag times and any water losses and accruals. Any researcher in this field should first understand where water comes from and how it will be utilized before any calculations are attempted. Only then manipulation of the release volume can commence. To precisely calculate this water release, accurate data is needed to ensure that the correct volume of water is released into the canal network. This can be done by verifying existing data with field data. To optimize the management of the irrigation scheme the fully implemented WAS program need to be installed and running at the scheme. A series of data and calculation verification needs to be executed. The exercise will show the adequacy and correctness of the available database WAS uses to do the release calculation from. This will ensure improved management of the irrigation scheme, catchment and water resource sustainability. It is planned that the information generated from this project will be used in the compilation of an integrated catchment management information system, currently underway in the school of Civil Engineering and Built Environment at the Central University of Technology, Free State, South Africa.

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37

Davuluri, Pavani. "Prediction of Breathing Patterns Using Neural Networks". VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/718.

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During the radio therapy treatment, it has been difficult to synchronize the radiation beam with the tumor position. Many compensation techniques have been used before. But all these techniques have some system latency, up to a few hundred milliseconds. Hence it is necessary to predict tumor position to compensate for the control system latency. In recent years, many attempts have been made to predict the position of a moving tumor during respiration. Analyzing external breathing signals presents a methodology in predicting the tumor position. Breathing patterns vary from very regular to irregular patterns. The irregular breathing patterns make prediction difficult. A solution is presented in this paper which utilizes neural networks as the predictive filter to determine the tumor position up to 500 milliseconds in the future. Two different neural network architectures, feedforward backpropagation network and recurrent network, are used for prediction. These networks are initialized in the same manner for the comparison of their prediction accuracies. The networks are able to predict well for all the 5 breathing cases used in the research and the results of both the networks are acceptable and comparable. Furthermore, the network parameters are optimized using a genetic algorithm to improve the performance. The optimization results obtained proved to improve the accuracy of the networks. The results of both the networks showed that the networks are good for prediction of different breathing behaviors.

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38

Longo, Luigi. "Tecniche costruttive post-terremoto 1693 nel sud-est della Sicila - Recupero e riuso dell'edilizia di base dei centri storici". Doctoral thesis, Università di Catania, 2013. http://hdl.handle.net/10761/1472.

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Il moltiplicarsi delle ricerche sulle tecniche costruttive, in particolar modo nell arco di tempo che intercorre dal terremoto del 1693, ( All'unnici di Jinnaru a vintin'ura a Jaci senza sonu s'abballava, cui sutta li petri e cui sutta li mura e cui a misericordia chiamava ) ad oggi, trova la sua ragione non solo nell esigenza di accrescere la conoscenza del patrimonio architettonico, dei materiali usati e delle maestranze, ma soprattutto la necessità di garantirne la conservazione. La ricerca scaturisce dall esigenza di reinterpretare le tecniche ed i procedimenti costruttivi tradizionali, al fine di un appropriato inquadramento della componente tecnologica, sia nella conservazione dei centri urbanizzati che nella definizione di soluzioni progettuali conformi ai caratteri tipologici del costruito. Lo studio dei processi costruttivi permette di ricercare gli aspetti tecnologici e fattuali, i sistemi di produzione e di approvvigionamento delle materie prime dell epoca, il relativo ambiente socio-economico, la committenza e le competenze delle maestranze; consentendo in tal modo di avere la più vasta conoscenza dell architettura che ci ha precorso e di operare verso un progetto di recupero in grado di salvaguardare sia i valori materiali che immateriali. In una logica del restauro di cui Cesare Brandi comprende il riconoscimento critico che costituisce la più valida premessa ad ogni aspettativa di salvaguardia e di buona conservazione, sottolineando che non esiste vero rimedio alle mutilazioni e ai danni subiti da un monumento, per trascuratezza o per attenzioni improprie; che si potrà effettuare una riparazione o anche una copia al vero, ma l originalità di ciò che si è perso rimarrà irrecuperabile. Ciò impone un approccio eminentemente conservativo, informato a criteri di massima cautela e di rispetto e ai principi guida elaborati in due secoli di riflessione per il tradizionale restauro artistico ed architettonico, criticamente e scientificamente inteso: la distinguibilità, il minimo intervento e la sua potenziale reversibilità, il rispetto per l autenticità e della materia antica, la compatibilità chimico-fisica delle aggiunte . Da qui nasce il progetto di un indagine riguardante le tecniche costruttive nel sud-est della Sicilia, in particolar modo riferita a quella che un tempo era la Val di Noto, e nello specifico alle Province di Catania (area etnea), di Siracusa e di Ragusa (area iblea); tutto ciò allo scopo di evitare il rischio di una cancellazione di ogni traccia, testimonianza e documento fattuale post sisma 1693, preso atto che antecedentemente a questa data non è rimasto alcun segno materiale. Il recupero del patrimonio edilizio esistente costituisce la prioritaria risposta alle attuali esigenze abitative in quanto i volumi costruiti risultano oggi preponderanti rispetto agli incrementi di popolazione. Per tale ragione l applicazione della metodologia tipologica risulta quella più rispondente alla salvaguardia del contesto costruito storico . Tale studio è stato condotto secondo le linee guida della metodologia sviluppata da Saverio Muratori, il quale ci ha consentito di evidenziare, con riferimento al singolo organismo architettonico, il percorso logico che lega le scelte tecnologiche, relative ai materiali e ai sistemi costruttivi, all organizzazione spaziale e alla risoluzione formale. Una approfondita lettura del tipo edilizio e del patrimonio insediativo minore storicamente consolidato va condotta come afferma lo stesso Muratori, attraverso le fasi, non temporali ma coscenziali, della logica, ovvero dei materiali e degli elementi tecnologici; dell economia, o delle tecniche costruttive; dell etica, o dell organizzazione funzionale; dell estetica, ovvero dell aspetto formale .

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39

Umberger, Pierce David. "Modeling the High Strain Rate Tensile Response and Shear Failure of Thermoplastic Composites". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23846.

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The high strain rate fiber direction tensile response of Ultra High Molecular Weight Polyethylene (UHMWPE) composites is of interest in applications where impact damage may occur. This response varies substantially with strain rate. However, physical testing of these composites is difficult at strain rates above 10^-1/s. A Monte Carlo simulation of composite tensile strength is constructed to estimate the tensile behavior of these composites. Load redistribution in the vicinity of fiber breaks varies according to fiber and matrix properties, which are in turn strain rate dependent. The distribution of fiber strengths is obtained from single fiber tests at strain rates ranging from 10^-4/s to 10^-1/s and shifted using the time-Temperature Superposition Principle (tTSP) to strain rates of 10^-4/s to 10^6/s. Other fiber properties are obtained from the same tests, but are assumed to be deterministic. Matrix properties are also assumed to be deterministic and are obtained from mechanical testing of neat matrix material samples. Simulation results are compared to experimental data for unidirectional lamina at strain rates up to 10^-1/s. Above 10^-1/s, simulation results are compared to experimental data shifted using tTSP. Similarly, through-thickness shear response of UHMWPE composites is of interest to support computational modeling of impact damage. In this study, punch shear testing of UHMWPE composites is conducted to determine shear properties. Two test fixtures, one allowing, and one preventing backplane curvature are used in conjunction with finite element modeling to investigate the stress state under punch shear loading and the resulting shear strength of the composite.
Ph. D.

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40

Qiao, Zhen. "Assessment of the mortality displacement in temperature-related deaths in Brisbane, Australia". Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/76280/1/Zhen_Qiao_Thesis.pdf.

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This thesis is a population-based ecological study designed to investigate the issue of mortality displacement (or "harvesting" effect) in the assessment of temperature-related deaths in Brisbane, Australia. It examines the temperature impacts on mortality, and assesses the harvesting effects on the temperature–related deaths. This study contributes to the knowledge base of understanding the temperature-mortality relationship and assists in formulating and evaluating public health intervention strategies within the context of climate change.

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41

Bahl, Dherya. "Design and Characterization of Topical Econazole Nitrate Formulations for Treating Raynaud’s Phenomenon". University of Toledo Health Science Campus / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=mco1501518069682334.

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42

Pelley, Katherine. "Factors affecting message intelligibility of cued speech transliterators". [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002580.

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43

Banu, Shahera. "Examining the impact of climate change on dengue transmission in the Asia-Pacific region". Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/66387/1/Shahera_Banu_Thesis.pdf.

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Dengue fever (DF) is a serious public health concern in many parts of the world. An increase in DF incidence has been observed globally over the past decades. Multiple factors including urbanisation, increased international travels and global climate change are thought to be responsible for increased DF. However, little research has been conducted in the Asia-Pacific region about the impact of these changes on dengue transmission. The overarching aim of this thesis is to explore the spatiotemporal pattern of DF transmission in the Asia-Pacific region and project the future risk of DF attributable to climate change. Annual data of DF outbreaks for sixteen countries in the Asia-Pacific region over the last fifty years were used in this study. The results show that the geographic range of DF in this region increased significantly over the study period. Thailand, Vietnam and Laos were identified as the highest risk areas and there was a southward expansion observed in the transmission pattern of DF which might have originated from Philippines or Thailand. Additionally, the detailed DF data were obtained and the space-time clustering of DF transmission was examined in Bangladesh. Monthly DF data were used for the entire country at the district level during 2000-2009. Dhaka district was identified as the most likely DF cluster in Bangladesh and several districts of the southern part of Bangladesh were identified as secondary clusters in the years 2000-2002. In order to examine the association between meteorological factors and DF transmission and to project the future risk of DF using different climate change scenarios, the climate-DF relationship was examined in Dhaka, Bangladesh. The results show that climate variability (particularly maximum temperature and relative humidity) was positively associated with DF transmission in Dhaka. The effects of climate variability were observed at a lag of four months which might help to potentially control and prevent DF outbreaks through effective vector management and community education. Based on the quantitative assessment of the climate-DF relationship, projected climate change will likely increase mosquito abundance and activity and DF in this area. Assuming a temperature increase of 3.3oC without any adaptation measures and significant changes in socio-economic conditions, the consequence will be devastating, with a projected annual increase of 16,030 cases in Dhaka, Bangladesh by the end of this century. Therefore, public health authorities need to be prepared for likely increase of DF transmission in this region. This study adds to the literature on the recent trends of DF and impacts of climate change on DF transmission. These findings may have significant public health implications for the control and prevention of DF, particularly in the Asia- Pacific region.

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44

Kim, Jisun. "Study of the Performance and Characteristics of U.S. Academic Research Institution Technology Commercialization (ARITC)". PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/494.

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This dissertation aims to provide a better understanding of the technology licensing practices of academic research institutions. The study identifies time durations in licensing and incorporates these into a model to evaluate licensing performance. Performance is measured by the efficiency of an institution's technology licensing process and efficiency changes over time, using Association of University Technology Managers annual survey data from 1991 to 2007. Organizational characteristics influencing the licensing performances of 46 U.S. research institutions also are explored. The study resulted in a new approach that integrates the identification of time lags in licensing, analysis of efficiency change, and exploration of the influence of organizational characteristics on efficiency change. A super-efficiency variable returns to scale data envelopment analysis (DEA) model was applied to the time-lag neutralized licensing data, to measure the efficiency of U.S. research institutions' licensing performance over time. The study also includes an innovative approach to resolving issues with the super-efficiency DEA model, including mathematical infeasibility and zero-data issues. The licensing mechanisms included in the study are disclosure, patent applications, patents issued, licenses and options executed, start-ups, and licensing income. The time duration from expenditure to licensing income, including all intermediating licensing processes, ranged from 2 to 27 years. The study identified the organizational characteristics related to licensing practice. Academic prestige and research quality are positively related to disclosure, patents granted, and start-up. The resources of a technology licensing office influences the number of licensing agreements, whereas licensing office experience has a positive relationship with start-ups. Increased licensing resources improve the efficiency of licensing practices, and a research institution with more dedicated licensing staff has improved licensing productivity. Private institutions improved their licensing practice more than public ones during the study period. On the other hand, institutions with a medical school demonstrated low efficiency. This dissertation fills a gap in the understanding of licensing practice and the organizational characteristics related to licensing performance. In addition, the study contributes to research methodology by providing a new approach to identifying time lags and improving the DEA method. The results, grounded in comprehensive observations over multiple time durations, provide an insight into the licensing practices of U.S. research institutions. The dissertation presents recommendations for research institutions based on the relationships identified among academic prestige, research intensity, organizational characteristics of the technology licensing office, and licensing performance.

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45

Kumar, Ravi R. "NUMERICAL INVESTIGATION AND PARALLEL COMPUTING FOR THERMAL TRANSPORT MECHANISM DURING NANOMACHINING". UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/425.

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Nano-scale machining, or Nanomachining is a hybrid process in which the total thermal energy necessary to remove atoms from a work-piece surface is applied from external sources. In the current study, the total thermal energy necessary to remove atoms from a work-piece surface is applied from two sources: (1) localized energy from a laser beam focused to a micron-scale spot to preheat the work-piece, and (2) a high-precision electron-beam emitted from the tips of carbon nano-tubes to remove material via evaporation/sublimation. Macro-to-nano scale heat transfer models are discussed for understanding their capability to capture and its application to predict the transient heat transfer mechanism required for nano-machining. In this case, thermal transport mechanism during nano-scale machining involves both phonons (lattice vibrations) and electrons; it is modeled using a parabolic two-step (PTS) model, which accounts for the time lag between these energy carriers. A numerical algorithm is developed for the solution of the PTS model based on explicit and implicit finite-difference methods. Since numerical solution for simulation of nanomachining involves high computational cost in terms of wall clock time consumed, performance comparison over a wide range of numerical techniques has been done to devise an efficient numerical solution procedure. Gauss-Seidel (GS), successive over relaxation (SOR), conjugate gradient (CG), d -form Douglas-Gunn time splitting, and other methods have been used to compare the computational cost involved in these methods. Use of the Douglas-Gunn time splitting in the solution of 3D time-dependent heat transport equations appears to be optimal especially as problem size (number of spatial grid points and/or required number of time steps) becomes large. Parallel computing is implemented to further reduce the wall clock time required for the complete simulation of nanomachining process. Domain decomposition with inter-processor communication using Message Passing Interface (MPI) libraries is adapted for parallel computing. Performance tuning has been implemented for efficient parallelization by overlapping communication with computation. Numerical solution for laser source and electron-beam source with different Gaussian distribution are presented. Performance of the parallel code is tested on four distinct computer cluster architecture. Results obtained for laser source agree well with available experimental data in the literature. The results for electron-beam source are self-consistent; nevertheless, they need to be validated experimentally.

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46

Linhart, Tomáš. "Potlačování šumu v řečových signálech za pomocí zpracování "atraktorů"". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217499.

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Speech signal is being used in the meaning of nonlinear dynamic system. As such, it is transform to multidimensional phase space, where filtration method based on time series neighbors of analysed signal is used. For embedding phase space methods time delay and false nearest neighbors are applied.

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47

Kleberg, Jens, e Moa Sundelius. "Påverkar revisorns kompetens och oberoende träffsäkerheten av givna fortlevnadsvarningar?" Thesis, Linköpings universitet, Företagsekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148860.

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According to generally accepted auditing standards, the auditor should give a going concern warning if there is substantial doubt regarding the client’s ability to survive. Research has shown that the accuracy is low because most companies receiving a going concern warning survives and most companies that declare bankruptcy has not received a going concern warning. This study focuses on the accuracy of given going concern warnings, because previous research in this area is limited. The results indicate that the competence and independence of the auditor has an impact on the accuracy of given going concern warnings and that the accuracy is higher when the time lag is longer. The study contributes with a wider definition of accuracy and shows that there are significant differences in accuracy between the big audit firms.
Bakgrund Enligt god revisionssed ska revisorer utfärda en fortlevnadsvarning i revisionsberättelsen om det råder tvivel angående klientens förmåga till fortsatt drift. Träffsäkerheten har i tidigare studier visat sig vara låg, då de flesta företag som får en fortlevnadsvarning inte går i konkurs och de flesta företag som går i konkurs inte har fått en fortlevnadsvarning. Tidigare studier har främst fokuserat på om företag som går i konkurs har fått en fortlevnadsvarning och denna studie fokuserar därför på typ I-fel, alltså att företag som fått en fortlevnadsvarning inte går i konkurs. Syfte Syftet med studien är att förklara om revisorns kompetens och oberoende påverkar träffsäkerheten av givna fortlevnadsvarningar. Dessutom syftar studien till att undersöka om träffsäkerheten påverkas av att tidsfördröjningen är längre än 12 månader efter fortlevnadsvarningen. Metod Studien har en deduktiv ansats och utgår från tidigare forskning, vilket legat till grund för studiens tre hypoteser. Vidare har studien en tvärsnittsdesign, där det kvantitativa datamaterialet främst har hämtats från svenska aktiebolags årsredovisningar. Slutsats Resultatet tyder på att revisorns kompetens och oberoende påverkar träffsäkerheten av givna fortlevnadsvarningar och att ökad tidsfördröjning har positiv påverkan på träffsäkerheten. Studien bidrar med en utvidgad definition av träffsäkerhet och visar på en signifikant skillnad i träffsäkerhet mellan de större revisionsbyråerna.

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48

Boschilia, Solana Meneghel. "Padrões espaço-temporais de macrófitas aquáticas em ambientes aquáticos continentais neotropicais". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/69704.

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A presente tese avaliou os efeitos de dois distúrbios de larga escala sobre estrutura das assembleias de macrófitas aquáticas em distintos ecossistemas neotropicais: uma grande depleção do nível da água no reservatório de Itaipu (Brasil/Paraguai) e os pulsos de cheia e seca na planície do Alto Rio Paraná. O primeiro capítulo da tese avaliou o impacto imediato e de médio prazo da depleção no nível hidrométrico sobre os padrões de co-ocorrência das espécies e a estrutura espaço-temporal da assembleia de macrófitas aquáticas em cinco braços do reservatório de Itaipu. O segundo e terceiro capítulos analisaram os padrões de diversidade beta e a contribuição relativa dos seus diferentes componentes (substituição de espécies e aninhamento) para a estruturação das assembleias no reservatório de Itaipu e na planície de inundação do Alto Rio Paraná, respectivamente. Diferentemente do esperado, a assembleia de macrófitas do reservatório de Itaipu revelou um padrão de organização das espécies diferente do acaso no ano em que ocorreu a depleção, provavelmente devido à colonização de novas espécies na margem exposta e à morte de muitos indivíduos pertencentes a diversas espécies do grupo das submersas. Imediatamente após o distúrbio, evidenciamos um padrão tipicamente aleatório de distribuição, devido ao reestabelecimento das espécies submersas, concomitantemente à colonização de espécies emergentes que haviam se estabelecido nas margens durante o distúrbio. Tanto no reservatório de Itaipu como na planície de inundação do Alto Rio Paraná, a substituição de espécies (turnover) revelou-se como principal mecanismo responsável pelos padrões de diversidade beta, o que provavelmente está diretamente associado com as diferenças de dinâmica hidrológica e limnológica entre cada ambiente dentro dos ecossistemas analisados (braços do reservatório e lagoas da planície).
The present thesis evaluated two large-scale disturbances upon the structure of aquatic macrophytes assemblages in distinct Neotropical ecosystems: an historic drawdown occurred in the Itaipu reservoir (Brazil/Paraguay) and the flood and drought pulses in the Upper Paraná River floodplain. The first chapter evaluated the immediate and long term impact of the drawdown over the co-occurrence patterns and the spatio-temporal structure of the aquatic macrophytes assemblage in five arms of the Itaipu reservoir. The second and third chapters analyzed the beta diversity patterns and the relative contribution of its different components (species turnover and nestedness) to the assemblage’s structure in the Itaipu reservoir and the Upper Paraná River floodplain, respectively. Contrary to expected, the macrophytes assemblage in the Itaipu reservoir presented a non-random spatial organization pattern of the macrophyte species in the year of the drawdown probably due to the colonization of the exposed area by new species and by the death of many individuals of submersed species. Immediately after the disturbance, we evidenced a random distribution guided by the reestablishment of the submersed species concomitantly with the emergents, which occupied the shore since the disturbance. Both Itaipu reservoir and the Upper Paraná River floodplain, the species turnover revealed to be the main process reflecting high values of beta diversity, which probably is directly linked with the distinct hydrological and limnological dynamic within the environments in each analyzed environment (reservoir arms and floodplains lagoons).

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49

Alqasas, Neveen. "Membrane Characterization for Linear and Nonlinear Systems: Upstream and Downstream Methods". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34979.

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Gas separation with polymer membranes are becoming one of the mainstream separation techniques for a myriad of industrial applications. Membrane technologies are recognized as a viable and economical unit operation compared to more conventional separation processes. The design and material selection of membrane separation processes depends highly on the transport properties of separated gas molecules within the membrane material. Therefore, to use efficient methods for gas membrane characterization is paramount for the proper design of membrane separation processes. A membrane can be typically characterized by three main properties: permeability, solubility and diffusivity. The permeability of a membrane is the product of its diffusivity and solubility, therefore obtaining two of the three parameters is sufficient to fully characterize a membrane. The time-lag method is one of the oldest and most used gas membrane characterization methods. However, it suffers from various limitations that make the method not applicable for many types of membranes. The focus in this study was to develop new gas membrane characterization techniques that are based on extracting the membrane properties from the upstream gas pressure measurements rather than only from the downstream pressure measurements. It is believed that characterizing the membrane based on the upstream pressure measurements would be highly useful in characterizing barrier materials which are usually difficult to characterize using the conventional time-lag method. Moreover, glassy polymers which are widely used in industry exhibit behavior associated with nonlinear sorption isotherms and, therefore, the conventional time-lag method is incapable of obtaining an accurate estimation of glassy polymer properties. As a result, sorption experiments to generate a sorption isotherm are usually required in addition to permeation experiments to fully characterize glassy polymer membranes. To quantify the errors associated with the conventional time-lag assumptions and to fundamentally comprehend the impact of nonlinearities on the time-lag method, a comprehensive numerical investigation has been undertaken using the finite difference method. The investigation has clearly put in evidence the effect of the various Langmuir parameters on the accuracy of the time lag and on the time required to achieve steady state. This investigation also allowed assessing the errors associated with the usual assumptions made on the boundary conditions in determining the time lag. In this study, three novel gas membrane characterization methods were developed and proposed. Two of the proposed methods are concerned with the characterization of membranes that can be represented with a linear sorption isotherm. These two methods are entirely based on the upstream pressure measurements. The third membrane characterization method that is proposed is based on the dynamic monitoring of both upstream and downstream pressure measurements and is applicable to systems that exhibit a nonlinear isotherm sorption behavior. The three proposed methods are promising and further experimental validation is recommended to determine their full range of applicability.

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Dang, Thi Anh Thu. "Impact of ambient temperature on hospital admissions for acute myocardial infarction in central coast of Vietnam". Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/123901/1/Thi%20Anh%20Thu_Dang_Thesis.pdf.

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Globally, there is evidence that extremes in temperature linked with climate change can exacerbate underlying health conditions and lead to hospitalization and premature death. This study examined the short-term effects of ambient temperature extremes on hospital admissions due to acute myocardial infarction (AMI) in three geographically dispersed provinces along the Central Coast region of Vietnam. We found that risk of AMI admission is associated with high and low temperatures, in part due to variation in sub-regional climate. Public health preparedness and multi-level interventions in communities and workplaces including factories and farms should attempt to reduce people's exposure to extreme temperature.

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Tesi sul tema "Time-lag"

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