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1
Fang, Chong he. "A high performance colour graphics display system." Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09SM/09smf2115.pdf.
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Bird, Paul. "Elementary students' comprehension of computer presented text." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29187.
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The study investigated grade 6 students' comprehension of narrative text when presented on a computer and as printed words on paper. A set of comprehension tests were developed for three stories of varying length (382 words, 1047 words and 1933 words) using a skills hierarchy protocol. The text for each story was prepared for presentation on a Macintosh computer using a program written for the study and as print in the form of exact copies of the computer screen. Students from two grade 6 classes in a suburban elementary school were randomly assigned to read one of the stories in either print form or on the computer and subsequently completed a comprehension test as well as a questionnaire concerning attitude and personal information. The responses from the comprehension tests were evaluated by graduate students in Language Education. The data evolved from the tests and questionnaires were analysed to determine measures of test construct validity, inter-rater reliability, and any significant difference in the means of comprehension scores for the two experimental groups for each story.
The results indicated small but insignificant differences between the means of the three comprehension test scores for computer and print. A number of students reading from the computer complained of eye fatigue. The scores of subjects reading the longest story and complaining of eye fatigue were significantly lower.Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate
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Sigut, Julius. "Road-rail intermodal terminals : modelling of operating performance." Thesis, Queensland University of Technology, 1995. https://eprints.qut.edu.au/36239/1/...%2036239_Sigut_1995.pdf.
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Road-rail transfer facilities ( or terminals, as they are referred to), represent a significant
component of intermodal transportation. The term "intermodal" refers to the
combination of two or more different modes used in transportation process of freight, in
case of this study taking place between the road and the rail. The complexity of
intermodal transportation has created a considerable demand for extensive application
of computer modelling of its operations. Intermodal infrastructure represents a multimillion
dollar capital investment, the utilisation of which has to be closely monitored.
In recent years some innovative technologies have found their way into intermodal and
some of them have been implemented with a various degree of success. One of those
successful innovations is a system commonly known as RoadRailer. Its main features
are bimodal trailers with the capability of being hauled on road as well as on rail.
The research presented here includes the development of simulation models which are
used to evaluate the operating performance of road-rail intermodal terminals. Two main
types of terminals are modelled, namely: conventional container transfer facilities and
RoadRailer trailer port facilities. The results of changing key operating resources and
the incidence of trailer breakdowns have been tested using the simulation models
developed as part of this thesis. Operations of other types of terminals and/or their
combinations (for example sea-rail) are not the subject of this work.
960 detailed observations of important operations activities were made by the author
during the research. The data collected were analysed to find the appropriate type of
statistical data distribution. The Chi-Square test was performed to determine the best-fit
line, with the conclusion, that the Erlang distribution was chosen correctly (Chapter 4.4
and Appendix F).
The RoadRailer model described in Chapter 6 was developed as a mean of assessment
of the new extended Adelaide RoadRailer terminal operation expected to commence
from 1 March 1994. Data representing real-life operating performance were to be
collected in due course, evaluated and used for the calibration of that model. However,
due to changed ownership of RoadRailer trailers and interstate operating rights (which
resulted in cessation of the interstate operation), the forecast scope of operation has not
been realised. Thus the necessary data have not become available for the planned model
calibration. An alternative approach had to be adopted, resolving the absence of data. A
comparison of results achieved under the past limited scale of operations, with that
given by the model, was performed. The RoadRailer terminal operation can take place
under different set of conditions which influence the final result. The impact of specific
conditions is investigated in depth in the model described in Chapter 6. The results thus
obtained provide to the best knowledge of the author the first successful attempt in
Australia to use computer simulation in modelling RoadRailer terminal operation.
Dynamic simulation was found to be a very efficient tool for investigation/modelling of
intermodal operations, both conventional and RoadRailer. As such it can be
recommended for practical application whenever a number of factors with variable
parameters of performance have to be considered The investigation of a Conventional terminal operation has proved the container
manipulations (it means loading, unloading, transferring and storage manipulations from
road to rail and vice versa) to be more efficient/productive than RoadRailer
manipulations performed under a comparable set of operating conditions. However, it is
recommended that a decision about the right choice between these two technologies be
made according to marketing objectives and results of a detailed comparison of
infrastructure capital costs.
The close investigation of RoadRailer terminal operations has revealed a considerable
impact of the number of resources deployed and the trailer breakdown ratio upon the
performance reliability. If a performance commensurate with the best world standards
is targeted, while sustaining a high breakdown ratio, then a relatively high level of
resources have to be used.
Reliability of trailers has been proved as a very important issue. The technical
complexity of trailer design raises the possibility of trailer breakdowns unless an
efficient preventive maintenance system is put in place. With the breakdown ratio
grater than 5% it is highly recommendable that a dedicated repair crew be used. If the
ratio exceeds 10% then successful performance is not achievable without such a crew,
especially in the long run. These results have nevertheless to be considered as valid for
the particular operating environment and as such do not claim general validity.
After setting out the results obtained using the terminal models, several topics closely
associated with the operating performance of road-rail terminals are discussed in
Appendices. These are based on the experience of the author and Australian National.
In Appendix G the key performance factors for a terminal are discussed, and associated
performance indicators are put forward.
In Appendix H the types of lifting equipment commonly used in terminals are described
together with their main advantages and drawbacks.
The strong relationship between the linehaul and terminal components of the overall
road-rail intermodal task is highlighted with respect to customer service variables in
Appendix I.
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Lindberg, Therese. "Discrete Event Simulation of Bus Terminals." Licentiate thesis, Linköpings universitet, Kommunikations- och transportsystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156646.
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Public transport is important to society as it provides spatial accessibility and reduces congestion and pollution in comparison to other motorized modes. To assure a high-quality service, all parts of the system need to be well-functioning and properly planned. One important aspect for the system's bus terminals is their capacity. This needs to be high enough to avoid congestion and queues and the delays these may lead to. During planning processes, various suggested designs and solutions for a terminal need to be evaluated. Estimating capacity and how well the suggestions will function is a challenging problem, however. It requires analysis of complex interactions and behaviour of the vehicles. This sort of analyses can preferably be carried out using microsimulation. Furthermore, a discrete event simulation approach can make use of the fact that the path of a vehicle through a terminal can readily be described by a sequence of events (such as arriving, starting to drive to a stop etc.). The overall aim of this thesis is to investigate how discrete event simulation can be used to evaluate bus terminal design and traffic control policies. The main contribution is the development of a method for bus terminal simulation. As a first step, a discrete event simulation model of a combined bus and tram stop is formulated. The model is tested on a real system where the current design is compared to an alternative one. The test shows that a model developed with a discrete event approach can be used to evaluate the situation at a stop and compare design alternatives. In the next step, a general discrete event simulation model of bus terminals is formulated. A modular approach is introduced, where a terminal can be constructed from a set of module building blocks. Another important contribution of the model is its spatial resolution that allows for queues and blockages to occur throughout the terminal. By applying the simulation model in a case study, it is shown that the model can be used to evaluate and compare various scenarios related to the layout, number of passengers and the outside traffic situation. Lastly, the bus terminal simulation model is used in a second case study in order to compare model output with empirical data. This study identified a number of factors that may have had an influence on differences between observations and simulation results and that is of interest to look further into. This includes the actual adherence to terminal rules and the effects of model parameters.
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Holt, Russell J. "The disk storage system of the High Level Software Engineering Workstation (HLSEW)." Thesis, Kansas State University, 1985. http://hdl.handle.net/2097/9851.
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Rabiner, Wendi Beth. "Network driven motion estimation for wireless video terminals." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43334.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 101-102).
by Wendi Beth Rabiner.
M.S.
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Gollakota, Shyamnath (Shyamnath Venkata Satyasrisai). "ZigZag decoding : combating hidden terminals in wireless networks." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44376.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (leaves 59-62).
This thesis presents ZigZag, an 802.11 receiver that combats hidden terminals. ZigZag exploits 802.11 retransmissions which, in the case of hidden terminals, cause successive collisions. Due to asynchrony, these collisions have different interference-free stretches at their start, which ZigZag uses to bootstrap its decoding. ZigZag makes no changes to the 802.11 MAC and introduces no overhead when there are no collisions. But, when senders collide, ZigZag attains the same throughput as if the colliding packets were a priori scheduled in separate time slots. We build a prototype of ZigZag in GNU Radio. In a testbed of 14 USRP nodes, ZigZag reduces the average packet loss rate at hidden terminals from 82.3% to about 0.7%.
by Shyamnath Gollakota
S.M.
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Dowler, Elizabeth Safety Science Faculty of Science UNSW. "Effects of neutral posture on muscle tension, pain and performance for computer users." Awarded by:University of New South Wales, 1998. http://handle.unsw.edu.au/1959.4/37113.
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This study focuses on developing a new approach to seated work positions. It was conducted on 67 office workers who use the Video Display Terminal (VDT) as a major function of their working day. Muscle tension was measured by surface electromyography when subjects were asked to adopt four selected working postures. Pain was measured before and after ergonomic intervention on the Nordic scale, which was modified for this study. Performance was measured on timed typing tests. A psychosocial questionnaire was used to determine influences of job demands, and a diagnostic assessment was performed to determine symptoms and pre-existing musculoskeletal conditions. Furniture was used to place subjects in desired positions during the clinical testing sessions and the extended intervention period. The chair seat pan was adjusted to a forward tilt to promote a lordotic curve of the low back, resulting in an erect upper body and upright head position. The desk and keyboard were adjusted to the proper height for each worker. A neutral wrist position was obtained by lowering and tilting the keyboard away from the user. Results revealed muscle tension scores in the upper trapezius and forearm extensors were significantly reduced when the workers were placed with the head in a midline position, with forward-tilting seating and with use of a negative sloping keyboard tray. Subjects reported low pain scores at pretest so no changes were noted after intervention. Loss of control over job elements, lack of job satisfaction, and fear of job loss were related to an increase in muscle tension. Only fear of job loss correlated to increased pain levels. There was no relationship between any of the job demand factors and performance.
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Noll, Noland LeRoy 1958. "GRAPHICS TERMINAL EMULATION ON THE PC." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276550.
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The HP2623 graphics terminal emulator is implemented on the PC for use with the Starbase graphics package provided on the departmental HP9000 series 500 computer system. This paper discusses the development and implementation of this emulator. A demonstration of its compatibility with Starbase is also provided along with a users' manual and a programmers' reference.
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May, Richard A. "Toward directly mediated interaction in computer supported environments /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10684.
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Rådström, Sofia. "HCI Design Patterns for In-Store Touch Screen Terminals." Thesis, Linköping University, Department of Computer and Information Science, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54958.
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Interactive media in public environments, such as touch screen kiosks, is a strongly growing toolfor offering service, information, advertising and entertainment. In order to achieve goodusability when designing the graphical user interface for a customer terminal, it is important tobe aware of the very specific requirements involved with such application. This master thesiscontributes to a framework for the interaction design of touch screen terminals in stores.
The purpose of the thesis was to discover usability problems and solutions to usability problemsin existing touch screen terminal interfaces. Moreover the work aimed at revealing what designpatterns can be used or created in order to meet the observed problems. Usability problems stemfrom underlying use qualities. These can be seen as forces in design patterns. It was found thatthe patterns would be more useful if structured into a pattern catalogue, containing both highand low-level patterns.
The study was preformed at Instoremedia, a company that, among other things, develops instore touch screen terminals. The product in focus was an interactive product cataloguedeveloped for Telia. The application was partly studied in situ. The study consisted of five steps:analytical evaluation, stakeholder interview, contextual inquiry, user analysis and design patterndevelopment. The study revealed problems, solutions, needs, goals etc, related to the use of theterminal. The final result is a proposed human computer interaction (HCI) design patterncatalogue for in-store touch screen terminals, which helps prevent the observed problems. Itconsists mostly of already known patterns. Three new patterns have been created. The aim isthat the pattern catalogue should be a helpful tool when making designs-decisions for new touchscreen terminals in the future.
Interaktiv media i publika miljöer, såsom pekskärmsterminaler, är på stark uppgång när detgäller att erbjuda service, information, marknadsföring och underhållning. För att uppnå höganvändbarhet i en kundterminals grafiska gränssnitt är det viktigt att vara medveten om despecifika krav som ställs på en sådan applikation. Detta examensarbete bidrar till ett ramverk fördesignen av pekskärmsterminaler i butiker.
Syftet med examensarbetet var att hitta användbarhetsproblem och lösningar till potentiellaanvändbarhetsproblem i existerande gränssnitt för pekskärmsterminaler. Vidare syftade arbetettill att ta reda på vilka designmönster som kan användas eller skapas för att möta de observeradeproblemen. Användbarhetsproblem bottnar i underliggande användarbehov. Dessa kan ses somkrafter i designmönster. Det visade sig att designmönster är mer användbara om de ordnas i enmönsterkatalog, som innehåller både hög- och lågnivå mönster.
Studien utfördes på Instoremedia, ett företag som bland annat utvecklar pekskärmsterminalerför butiker. I fokus stod en interaktiv produktkatalog utvecklad för Telia. Applikationenstuderades delvis in situ. Studien bestod av fem steg: analytisk utvärdering, intressentintervju,kontextuell undersökning, användaranalys och designmönsterutveckling. Studien avslöjadeproblem, lösningar, behov, mål etc., relaterade till användandet av terminalen. Det slutgiltigaresultatet är en föreslagen designmönsterkatalog för pekskärmsterminaler i butiker, somerbjuder lösningar till de observerade problemen. Katalogen består till största delen av redankända mönster. Tre nya designmönster har utvecklats. Målet är att mönsterkatalogen ska kunnaanvändas som ett redskap under framtida design.
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Hadjiyiannis, George Ioannou. "A low power, low bandwidth protocol for remote wireless terminals." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/39374.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (leaves 74-75).
by George Ioannou Hadjiyiannis.
M.S.
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Strauss, Johann. "Development of the MINITEL peripheral port adaptor (MPPA)." Thesis, Cape Technikon, 1992. http://hdl.handle.net/20.500.11838/1160.
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Thesis (M.Diploma in Electrical Engineering)--Cape Technikon, 1992This thesis describes how an adaptor board was developed to enable serial devices, such as modems and serial printers operating on RS-232 signals, to be used in conjunction with the MINITEL terminal. Furthermore it enables parallel Centronix interfaces to be Used in conjunction with the MINITEL terminal. The revolutionary 87C751 microprocessor was fully researched, and implemented in the project. Two marketable products emerged during the course of the project: • 1. The 8031-processor solution 2. The 87C751-processor solution
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Roza, Fernanda Albieri Marchi Lopes. "A influencia da altura da tela do computador na ocorrencia da dor cervical." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311993.
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Orientador: Satoshi KitamuraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-11T11:10:12Z (GMT). No. of bitstreams: 1 Roza_FernandaAlbieriMarchiLopes_M.pdf: 2315417 bytes, checksum: 5134e985d650d5e2597bd5c8cddcedb7 (MD5) Previous issue date: 2007
Resumo: A literatura nacional e principalmente internacional consultada, apresenta muitos desacordos sobre a altura mais apropriada da tela do computador, em relação à altura dos olhos do operador, visando propiciar ao usuário, melhores condições de trabalho. Alguns autores, associações e organizações vinculadas à ergonomia sugerem que o topo da tela do computador deva estar na linha dos olhos do indivíduo ou levemente para baixo. Através do presente estudo pretende-se propor um novo posicionamento da tela do computador, visando um melhor posicionamento para a coluna cervical, de modo que sua curvatura fique a mais fisiológica possível; e analisar sua influência na sintomatologia da região cervical. O método utilizado constou de três etapas: (1) aplicação de um questionário sobre sintomas, utilizando uma escala analógica visual (1 a 10), na qual o indivíduo assinalou o seu nível de dor; em três regiões do corpo que mais o incomodava ao utilizar o computador; (2) a medição para determinar a altura dos seus olhos em relação à parte central da tela e (3) aplicação do mesmo questionário, após um período de 90 dias de observação, para que se pudesse avaliar a eficácia da intervenção em relação à dor, quanto à sua localização e à sua intensidade. O estudo foi realizado nos setores administrativos de duas empresas. O ¿grupo intervenção¿ (empresa A) com um total de 24 sujeitos (15 mulheres e 9 homens), e média de idade de 30.2(DP=9.4); recebeu a orientação e a intervenção ergonômica (alteração da altura da tela do computador). O ¿grupo controle¿ (empresa B), com um total de 20 sujeitos (7 mulheres e 13 homens), e média de idade de 31.6(DP=7.1); recebeu a orientação ergonômica do posto de trabalho, sem alterar a altura da tela. A intervenção permaneceu em vigor durante um período aproximado de três meses em que o indivíduo desenvolveu o seu trabalho habitual normal. No final do período, os dados do questionário e da escala analógica visual antes e depois da intervenção foram registrados através do programa computacional SAS (Statistical Analysis System). Os resultados mostram que houve queda significativa na média da medida da dor das dez áreas analisadas (cervical, ombros, dorsal, cotovelos, antebraço, lombar, punhos/mãos/dedos, quadris e coxas, joelhos e tornozelos/pés), sendo semelhantes estatisticamente nas duas empresas. A região cervical apresentou valores médios maiores (sem significância estatística) do declínio da medida da dor na empresa A; mas com diferença estatisticamente significante entre homens e mulheres (p<0.05).Por outro lado,observou-se que não há associações do nível de dor com as faixas etárias e o uso do computador por dia. Os resultados corroboram para demonstrar os benefícios da intervenção ergonômica em postos de trabalhos informatizados, principalmente na minimização dos desconfortos músculo esqueléticos e num ambiente mais confortável e adequado para o trabalho
Abstract: Considering both national and international researched literature, one can notice several disagreements about the most appropriate height of the computer screen in relation to operator eyes' level, being here the target to provide better working conditions to the user. Some authors, associations and organizations suggest that the top of the computer screen should be at the line of the person¿s eyes, or slightly down.This study proposes a new position of the computer screen so that the curvature of the cervical spines is the most physiological as possible. F Furthermore, it, intends to analyze the influence of the symptoms of the cervical region. The method applied consisted of tree phases:(1) a survey on the symptoms, using a vision analogical scale (1 to10) in which the person mentioned his pain level in three regions of his body where computer disturbed him the most while using it;(2) the measurement to determine the level of the eyes related to the central spot of the screen;(3) the application of the same survey, after 90 days of observation, so to evaluate the effectiveness of the intervention in relation to the pain, as well as its location and intensity. The study was done in the administrative sectors of two enterprises. The ¿intervention group¿(Company A) with a total of 24 persons (15 women and 9 men) whose age average of 30.2(SD=9.4)received the guidance and ergonomic intervention by changing the level of the computer screen. The ¿control group¿(Company B) with a total of 20 persons(13 women and 7 men )whose age average of 31.6(SD=9.4)received the guidance of ergonomics for their workstation, without changing the level of the screen. The intervention remained under effect for approximately three months during which the persons did their usual and normal work. At the end of the period both the survey data and the usual analogical scale were recorded by a computer software called SAS (Statistical Analysis System), before and after the intervention. The results showed that there was significant reduction in the average measurement of the pain of the ten analyzed areas ( cervical, shoulder, dorsal,elbow,forearm,back,wrists,hands, fingers, hips and thighs, knees and ankles, feet)being statistically similar for both companies. The cervical region results showed higher average values (no statistical significance) of reduction in the extent of pain in Company A , but with statistically significant differences between men and women(p>0.05).On the other hand, it was observed that there is no association between the pain level and the different ages of the users and the daily use of computer. The results confirm the benefits of ergonomic intervention at computer work, mainly to minimize the muscle and skeletal discomforts in a more comfortable and appropriate environment for the job
Mestrado
Epidemiologia
Mestre em Saude Coletiva
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Gili, Carla, and Estefanía Soler. "Comparison and Evaluation of Different Types of Vehicles to Transport Containers within an Intermodal Terminal." Thesis, Blekinge Tekniska Högskola, Avdelningen för programvarusystem, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2926.
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Due to globalisation, transport policies have been changing and adapting to increase the demands and the needs of the market. Sea ports have a major role in the economic system in which they coordinate the transport of large volumes of cargo in long distances with a high level of productivity. The growth of handling cargo has led to increase congestion in roads because roads are the most used method to transport goods between port and its hinterland. This is the reason why many West European ports are working with train terminals as an alternative form of transport. As part of an intermodal case of study, we have focused on train terminal operations at the port of Barcelona, because currently there is not enough capacity, but it is expected to increase within the next ten years. Moreover, because of the limited geographicalarea, it is important to take in consideration the method for managing the logistics within the container terminal in Barcelona. The objective of this study is to develop a model to analyse and evaluate different types of horizontal transport between the yard and the train terminal at the port of Barcelona in order to identify the most suitable transport system. We compare five different transport systems under three scenarios. The results indicate that some horizontal transport systems are more efficient than others.
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Chervyakov, Anatoly. "Simulation-based evaluation of berth allocation policies of container terminals." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik och datavetenskap, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1523.
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The aim of this investigation is to test and verify a hypothesis concerning policies for berth allocation to ships in a container terminal. The chosen domain is a rich research area where simulation could be used. Because of the high amount of variables involved and demand for optimal usage of available resources management of a container terminal is a great challenge.
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Li, Mingkun, and 李明琨. "Efficient algorithms for designing yard storage templates for export containers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45963332.
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Lee, Man-ying Nicole, and 李文英. "An AIS-based vehicle control framework in port container terminals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41508361.
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Murnick, Jonathan G. (Jonathan George) 1972. "Coordination between presynaptic and postsynaptic properties measured at single terminals in hippocampal cultures." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/87455.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.Vita.
Includes bibliographical references (p. 68-71).
I examined the spatial scale at which pre-synaptic activity interacts with synaptic strength and developmental events in the post-synaptic cell. I performed this work in primary hippocampal cultures of postnatal Sprague-Dawley rats after 8-10 days in vitro. I measured electrophysiologically the functional addition of GluR2 and NR2A subunits to AMPA and NMDA receptors, respectively, as well as the absolute strength of AMPA- and NMDA-mediated currents. I examined both spontaneous quantal events and local responses using glutamate iontophoresis at putative single-synaptic sites. I monitored pre-synaptic strength via vesicle staining with FM dyes. I found an inverse correlation between pre-synaptic and post-synaptic strength at individual synapses: Intensity of presynaptic FM-staining was inversely correlated with AMPA current magnitude measured by local iontophoretic stimulation. I also found a negative correlation at individual puncta between FM-staining intensity and decay time of iontophoretically-evoked NMDA decay current. Presumably, this correlation reflects a higher proportion of NR2A subunits at presynaptically more active synapses. I propose that homeostatic feedback mechanisms may operate at a subecellular level to maintain excitatory synaptic input at a single synapse or within a dendritic branch. In order to stimulate individual synaptic sites, I used a novel iontophoresis system, presented here. The system incorporates a 0.1 [mu]m electrode tip for local stimulation, combined with fast capacitance compensation to achieve high-speed application from a high-resistance tip.
(cont.) Ejection of fluorescent dye from the electrode shows that transmitter can be limited to the width of a single synapse and to a time scale similar to an endogenous event. The speed and localization of transmitter is confirmed by iontophoretically stimulating single labeled synapses in cultured hippocampal neurons held under voltage clamp. The amount of transmitter ejected is linear and reproducible over a physiologically relevant range, making this technique useful for examining receptor kinetics and receptor insertion/removal. The system should be capable of delivering any charged neurotransmitter.
by Jonathan G. Murnick.
Ph.D.
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Feldman, Jon 1975. "The Directed Steiner Network problem is tractable for a constant number of terminals." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86450.
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Scott, Andrew James. "The impact of touch screen technologies on the product interface." Thesis, Queensland University of Technology, 1998.
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Knox, Stephen T. "An investigation of resolution and addressability requirements for digital display systems used in word-processing and computer-aided-drafting applications." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/3697.
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Two hardware factors contributing to the overall image quality of digital CR Ts are display resolution and addressability. The relationship between these two factors and human performance was modeled by a metric of display quality, the Resolution Addressability Ratio (RAR), and investigated within the contexts of Word-Processing (WP) and Computer-Aided-Drafting (CAD) tasks. The findings indicate a perceptual limit to MTF bandwidth improvements, and significant differences iii display quality requirements between the two applications. The regression of image quality as a function of RAR metric values resulted in an r2 = 0.94 for the WP task and an r2 = 0.79 for the CAD task. These findings are discussed in terms of engineering guidelines for the design of CRT and flat-panel displays for applications which vary by the amount of the density of information in their typical displays.
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Lee, Hyun Jean. "The screen as boundary object." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28226.
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Thesis (M. S.)--Literature, Communication, and Culture, Georgia Institute of Technology, 2009.Committee Chair: Mazalek, Ali; Committee Member: Bolter, Jay David; Committee Member: Do, Ellen Yi-Luen; Committee Member: Nitsche, Michael; Committee Member: Winegarden, Claudia R.
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D'Angelo, John J. "A Study of the Relationship Between the Use of Color for Text in Computer Screen Design and the Age of the Computer User." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc663711/.
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This study addresses an individual's performance, relating it to eyesight changes due to the aging of the individual and to color computer screens used for computer-based-instruction not designed specifically for older students.
This study determines how existing research in gerontology, human-computer interface, and color use in visual graphics can be applied to the design of computer screen displays containing color text and backgrounds and how various color combinations will affect performance by adult learners forty years of age and older.
The results of this research provide software developers and instructional designers guidelines to use when designing computer screen displays for use in instructional computing settings involving older adults.
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Al-Mohandes, Ibrahim. "Energy-Efficient Turbo Decoder for 3G Wireless Terminals." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/838.
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Since its introduction in 1993, the turbo coding error-correction technique has generated a tremendous interest due to its near Shannon-limit performance. Two key innovations of turbo codes are parallel concatenated encoding and iterative decoding. In its IMT-2000 initiative, the International Telecommunication Union (ITU) adopted turbo coding as a channel coding standard for Third-Generation (3G) wireless high-speed (up to 2 Mbps) data services (cdma2000 in North America and W-CDMA in Japan and Europe).
For battery-powered hand-held wireless terminals, energy consumption is a major concern. In this thesis, a new design for an energy-efficient turbo decoder that is suitable for 3G wireless high-speed data terminals is proposed. The Log-MAP decoding algorithm is selected for implementation of the constituent Soft-Input/Soft-Output (SISO) decoder; the algorithm is approximated by a fixed-point representation that achieves the best performance/complexity tradeoff. To attain energy reduction, a two-stage design approach is adopted.
First, a novel dynamic-iterative technique that is appropriate for both good and poor channel conditions is proposed, and then applied to reduce energy consumption of the turbo decoder. Second, a combination of architectural-level techniques is applied to obtain further energy reduction; these techniques also enhance throughput of the turbo decoder and are area-efficient. The turbo decoder design is coded in the VHDL hardware description language, and then synthesized and mapped to a 0. 18μm CMOS technology using the standard-cell approach. The designed turbo decoder has a maximum data rate of 5 Mb/s (at an upper limit of five iterations) and is 3G-compatible. Results show that the adopted two-stage design approach reduces energy consumption of the turbo decoder by about 65%.
A prototype for the new turbo codec (encoder/decoder) system is implemented on a Xilinx XC2V6000 FPGA chip; then the FPGA is tested using the CMC Rapid Prototyping Platform (RPP). The test proves correct functionality of the turbo codec implementation, and hence feasibility of the proposed turbo decoder design.
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Decker, Jennie Jo. "Display spatial luminance nonuniformities: effects on operator performance and perception." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54510.
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This dissertation examined the effects of display spatial luminance nonuniformities on operator performance and perception. The objectives of this research were to develop definitions of nonuniformity, develop accurate measurement techniques, determine acceptable levels of nonuniformities, and to develop a predictive model based on user performance data.
Nonuniformities were described in terms of spatial frequency, amplitude, display luminance, gradient shape, and number of dimensions. Performance measures included a visual random search task and a subjective measure to determine users' perceptions of the nonuniformities. Results showed that users were able to perform the search task in the presence of appreciable nonuniformities. lt was concluded that current published recommendations for acceptable levels of nonuniformities are adequately specified. Results from the subjective task showed that users were sensitive to the presence of nonuniformities in terms of their perceptions of uniformity.
Specifically, results showed that as spatial frequency increased, perceived uniformity ratings increased. That is, users rated nonuniformities to be less noticeable. As amplitude and display luminance increased, the users' ratings of perceived uniformity decreased; that is, they rated the display as being farther from a uniform field. There were no differences in impressions between a sine and triangle gradient shape, while a square gradient shape resulted in lower ratings of perceived uniformity. Few differences were attributed to the dimension (1-D versus 2- D) of the nonuniformity and results were inconclusive because dimension was confounded with the display luminance.
Nonuniformities were analyzed using Fourier techniques to determine the amplitudes of the coefficients for each nonuniformity pattern. These physical descriptors were used to develop models to predict users' perceptions of the nonuniformities. A few models yielded good fits of the subjective data. lt was concluded that the method for describing and measuring nonuniformities was successful. Also, the results of this research were in strong concurrence with previous research in the area of spatial vision.Ph. D.
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Brown, Martin Reid. "Hardware Ergonomic Considerations in Middle School Classroom Computer and Video Display Terminal Installations." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc332559/.
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The purpose of this study was to determine the extent specific ergonomic factor implementations in computer and video display terminal (VDT) installations for student use in middle school classrooms. The data interpretations using existing furniture without modification or adaptation. Of all the seating observed, 75% of the seating met standards for middle school students. Keyboards and video display screens had been placed on existing tables and were all higher than ergonomically desirable for middle school students or adults.
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Aguilera, Camilo. "Retention and productivity in industrial search and scan tasks." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Latham, Charles V. (Charles Vernon). "The Effect of Color in Computer Assisted Instruction on Vocabulary Retention Rates and Computer Attitudes of Selected Upward Bound Students." Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc331796/.
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The purpose of this study was to determine the effect on selected Upward Bound students' vocabulary retention rate and attitude toward computers when using color in a computer assisted instructional (CAI) program. Past research on the use of color in the educational process does not answer questions about possible effects it may have when used in CAI programs. Specific areas addressed by this study include: (1) differences in color computer assisted instructional software and achromatic versions of the lesson, (2) differences in the short-term vocabulary retention rate for color versus achromatic versions, (3) differences in the long-term vocabulary retention rate for color versus achromatic versions, (4) differences on the affective attitude scale for color versus achromatic versions, (5) differences in short-term memory based on gender and computer experience, (6) differences in long-term memory based on gender and computer experience and (7) differences on the affective attitude scale based on gender and computer experience. Subjects in the experiment were high school students participating in Upward Bound programs at Texas Christian University and the University of North Texas. A pretestposttest design was used and data were obtained from seventy-one students. A CAI program presented students with twenty words and definitions via a drill and practice mode. The words came from Schuster's list of rare and seldom used words considered easy to learn. Two computer systems were used in this study, achromatic and color. Students completed the Computer Attitude Scale at the beginning and end of the CAI lesson. A pretest, immediate posttest and two week delayed posttest were administered to both experimental groups. Analysis of the data revealed a significant difference in long-term memory based on gender and computer experience. Girls using the color version of the lesson scored significantly higher on the delayed posttest than girls using the achromatic version.
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Estepa, Adriana Paola Castillo 1989. "Saúde visual no trabalho e a síndrome da visão do computador em professores universitários." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312509.
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Orientador: Aparecida Mari IgutDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Introdução: Os computadores são parte da vida moderna e seu uso deles massificado; diariamente as pessoas passam várias horas diante de uma tela pelas diversas facilidades no trabalho, no lazer, na conectividade, entre outros. Ao mesmo tempo também trazem riscos à saúde de seus usuários, sendo descritos problemas psicológicos, problemas musculoesqueléticos e problemas visuais; estes últimos apresentam uma alta prevalência (50%-70%) e os sintomas visuais e oculares, que trazem incômodos para realização de atividades com o computador, reduzem a produtividade dos trabalhadores e diminuem a qualidade de vida dos usuários de computadores. Estes efeitos à saúde visual têm sido pouco estudados pela comunidade científica. Objetivos: Levantar a frequência de casos da Síndrome da Visão do Computador em professores universitários e identificar os fatores de risco associados à presença da CVS. Metodologia: Trata-se de estudo de tipo transversal observacional e participam professores de uma universidade pública do Estado de São Paulo; foram aplicados dois questionários, um versando sobre aspectos do trabalho e do uso de computadores e outro, sobre sintomas oculares e visuais. Além disso, foram realizados exames visuais. A coleta de dados foi feita entre os meses de Fevereiro a Dezembro de 2013 no campus da universidade. Critérios de Inclusão: Professores da universidade. Critérios de Exclusão: Professores que não usem o computador. Resultados: Em uma amostra de 53 professores a Síndrome da Visão do Computador foi encontrada em 30 professores, 19 deles classificados com a forma leve da Síndrome, 10 com a moderada e 1 com a severa; os sintomas que mais incomodaram os professores foram fadiga (30 participantes), ressecamento ocular (20 participantes), irritação ocular (17 participantes). Foram encontrados problemas binoculares em 27 dos 53 professores e diminuição na produção lacrimal em 12/53. Conclusões: Os professores universitários são uma população com uma alta prevalência da Síndrome da Visão do computador, na amostra apresentou-se a síndrome em mais da metade dos participantes 30/23(56%), concordando assim com as prevalências da Síndrome encontradas nos estudos internacionais. Três variáveis foram associadas significativamente ao aparecimento da CVS nos professores universitários, a idade que minimiza as chances de ter CVS (OR: 0,91 IC: 0,83/0,97 P-value: 0,015), as horas de uso diárias no computador que aumentam as chances de apresentar CVS (OR: 1,26 IC: 1,05/1,57 P-value: 0,021), e os problemas vergenciais como insuficiência ou excesso de convergência ou divergência, os quais estão associados positivamente com o aparecimento da síndrome (OR: 3,24 IC: 1,06/10,49 P-value: 0,042). Palavras chave: Síndrome da Visão do Computador, astenopia, videoterminais, ergonomia, saúde do trabalhador
Abstract: Computers are part of modern life, their use sprayed and people spend several hours using them as they bring several facilities in work, leisure, connectivity, among others. Computers also brought risks to the health of its users, psychological problems, musculoskeletal problems and visual problems, although the latter with a high prevalence (50% -70%) and with visual and ocular symptoms that diminish the quality of life of users, bother working with the computer and reduce worker productivity, has been little studied by the scientific community. Objectives: The study aims to estimate the cases frequency of the Computer Vision Syndrome in teachers and to identify risk factors associated with the presence of CVS. Methodology: This is a cross-sectional-observational study with teachers of a public university which two questionnaires and a visual test is performed to find and evaluate the possible symptoms of Computer Vision Syndrome of as well as their associated factors. The survey is conducted between the months of February to December 2013 at the University campus. Inclusion Criteria: Teachers and researchers at university. Exclusion Criteria: Teachers and researches that do not use the computer. Results: In a sample of 53 teachers of Computer Vision Syndrome was found in 30 teachers, 19 were classified as mild form of the syndrome, 10 with moderate and 1 with severe, the symptoms that bother the teachers were fatigue (30 participants), ocular dryness (20 participants), eye irritation (17 participants). Binocular problems were found in 27 of the 53 teachers and decrease in tear production in 12/53. Conclusions: The teachers are a population with a high prevalence of the Computer Vision Syndrome, the sample presented the syndrome in more than half of the participants 30/23 (56%), thus agreeing with the prevalence of the syndrome found in international studies. Three variables were significantly associated with 5 % with the onset of CVS on university teachers , the age that minimizes the chances of having CVS (OR: 0.91 IC: 0.83/0.97 P-value: 0.015), hours daily use of the computer that increase the chances of presenting CVS (OR: 1.26 IC: 1.05/1.57 P-value: 0.021), and vergenciais problems like deficiency or excess of convergence or divergence, which are positively associated with the onset of the syndrome (OR: 3.24 IC: 1.06/10.49 P-value: 0.042). Keywords: Computer Vision Syndrome, asthenopia, video display terminals, ergonomics, occupational health
Mestrado
Epidemiologia
Mestra em Saúde Coletiva
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Wall, Thomas Aubrey. "A federated simulation approach to modeling port and roadway operations." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33928.
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This research develops a computer simulation method for federating an Arena© port operations model and a VISSIM© roadway network operations model. The development of this method is inspired by the High Level Architecture (HLA) standard for federating simulations, and incorporates several elements of the HLA principles into its design. The federated simulation model is then tested using a time-lag experiment to demonstrate the presence of feedback loops between federated model components wherein changes to input parameters of one model during runtime can be shown to affect the operational performance of the other model. This experiment also demonstrates how several initial transient phase and steady state operating characteristics of the federated system can be determined from the federation output data.
The results indicate that the method developed in this study is capable of capturing the dynamic interaction of two models in federated simulation. It is shown that feedback loops can exist between two models in federated simulation. Most notably, the federation output shows that increased traffic volume in the roadway network model influences the accumulation of containers in the port terminal queue of the port model. The federation output also shows that increased container volume leaving the port terminal model affects both port and road truck utilization, as well as the total number of port trucks in the roadway network model.
Challenges and future directions for research in federating transportation-related simulations are also presented.
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Payumo, Elizabeth. "A comparison of the effects of reading from a VDU and from paper as measured in terms of reading speed and comprehension." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1992. https://ro.ecu.edu.au/theses/1691.
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This study investigates the legibility and visual effects of eight combinations of font and colour on VDU and two different fonts on paper. Forty subjects, sixteen females and twenty-four males, were exposed to three of the ten different conditions, one in each of the set of readings, on either VDU or paper. They were asked to read different sets of stories in each condition on different days where each condition lasted for approximately two hours. Reading speed and comprehension scores were measured in every story read in the set of stories. The change of mood and physical symptoms states of the subjects were measured at the beginning and end of each conditions. Subjective ranking of the combinations of font and colour in the VDU environment were elicited from the subjects.
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Whattananarong, Krisana. "A Cross-Culture Study of Color Preferences on a Computer Screen Between Thai and American Students." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc332612/.
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The purpose of this investigation was to determine the color preference of Thai and American students for text and background computer color combinations. The primary purpose of this study was to determine if there were differences between Thai and American students' computer color combination preferences.
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Moscovic, Sandra A. "Development of time and workload methodologies for Micro Saint models of visual display and control systems." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/40443.
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Arnaut, Lynn Y. "An evaluation of display/control gain in the context of control-display interface optimization." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49978.
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Display/control gain is the amount of movement that occurs on a display in response to a unit amount of movement on the control. Two studies were conducted to determine the adequacy of identifying the optimum gain for an interface as a method of control-display interface optimization.
The first study examined the effects of changes in both the maximum control input and the display width on target acquisition performance with a touch tablet and a trackball. The hypothesis that an interaction between the control input and the display output would determine performance was not supported for either device. There was a main effect of the control input for the touch tablet, and significant effects of the control input and the display width for the trackball. The results also indicate that, at least for the touch tablet, gain is not a sufficient specification for performance.
The second study evaluated the effects of changes in the display amplitude, the display target width, and the control amplitude. There were significant interactions among these three factors for both touch tablet and trackball target acquisition performance. These results extend the findings of the first study with respect to the inability of gain to predict performance. In addition, the inadequacy of Fitts' Law as it applies to the given interfaces is discussed.Ph. D.
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Lee, Jennifer Ann. "Evaluating ITS Investments in Public Transportation: A Proposed Framework and Plan for the OmniLink Route Deviation Service." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34416.
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When implementing an intelligent transportation system (ITS), stakeholders often overlook the importance of evaluating the system once it is in place. Determining the extent to which the objectives of an investment have been met is important to not only the agency involved, but also to other agencies, so that lessons are learned and mistakes are not repeated in future projects. An effective evaluation allows a transit provider to identify and address areas that could use improvement. Agencies implementing ITS investments often have different goals, needs, and concerns that they hope their project will address and consequently the development of a generic evaluation plan is difficult to develop. While it is recognized that the U.S. Department of Transportation has developed guidelines to aid agencies in evaluating such investments, this research is intended to complement these guidelines by assisting in the evaluation of a site specific ITS investment. It presents an evaluation framework and plan that provides a systematic method for assessing the potential impacts associated with the project by defining objectives, measures, analysis recommendations, and data requirements. The framework developed specifically addresses the ITS investment on the OmniLink local route deviation bus service in Prince William County, Virginia, but could be used as a basis for the evaluation of similar ITS investments. The OmniLink ITS investment includes an automatic vehicle location (AVL) system, mobile data terminals (MDTs), and computer-aided dispatch (CAD) technology.Master of Science
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Lacaze, Denise Helena de Castro. ""Efeitos de um programa de exercícios no desconforto músculoesquelético dos segmentos corporais de operadores de telemarketing"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-16082006-153109/.
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Este estudo tem por objetivo avaliar o nível de desconforto, através da Escala Visual Analógica (EVA), o Mapa de Segmentos Corporais de Corlett e Bishop (MSC) e o Questionário de Fadiga de Chalder (EFC) em operadores de telemarketing. A coleta de dados foi realizada uma vez por semana, ao longo de 2 meses de aplicação do programa de exercícios. A análise estatística sugere diminuição do crescimento do desconforto postural nos dois grupos, sendo mais acentuada no grupo experimental. Foi observada também diminuição significativa dos níveis de EVA e redução da freqüência e da prevalência de segmentos doloridos no MSC, ao se comparar dados da primeira e da última semana do estudo realizado. Quanto à fadiga também houve melhora em todas as variáveis do questionário de Chalder, indicando presença de efeitos significativos na diminuição dos níveis de fadiga. Assim, os programa de exercícios mostraram-se efetivos para diminuir o desconforto músculo-esquelético e a fadiga entre os operadores de telemarketingThe objective of this survey is to assess the telemarketing operators discomfort and mental and physical fatigue at the airway company call center before and after applying an exercise program. The objective of this survey is to assess the telemarketing operators discomfort and mental and physical fatigue at the airway company call center before and after applying an exercise program. The body map of Corlett and Bishop with a visual analogic scale and the Chalder fatigue questionnaire was applied to 84 telemarketing operators from the experimental and control groups. The experimental group has attended a 10 minutes exercise daily session and the control group a 10 minutes daily rest break. The exercise showed that is more effective than a rest break to prevent discomfort development and is important to repetitive strain injuries prevention because discomfort is one of the main predictors of this group of diseases
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Fourie, Sarie Marissa. "3D measurement of cervical and thoracic postural dynamism in sitting : a pilot study." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85712.
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Thesis (MScPhysio)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The aim of this study was to improve the measurement of postural dynamism in the sitting position using a three-dimensional (3D) motion analysis system. The primary objective was to describe pilot data for postural dynamism of the cervical and thoracic spines while working at a desktop computer. The secondary objective was to refine the process of posture measurement and analysis by decreasing data processing time. Certain factors in 3D motion analysis can lead to an increase in gaps in data collected during trial capture, which in turn will lead to a longer time of data processing. In the first phase of this study, a number of such factors were identified and altered. A series of pilot studies was performed to test the improvement of data processing time when altering these factors. In the first two pilot studies, camera and tripod positionings were explored and refined, workstation layout and anatomical landmark marker placement were investigated, and optimal capture frequency was established. In both these pilot studies, outcomes were established by means of trial and error by experimenting with a variety of different options for the different outcomes. In the third pilot study, computer software which provides computer tasks for the participant during primary trial capture was tested. Two independent computer users performed all the activities as per software, after which they were required to give oral feedback and suggestions on improvement in terms of user friendliness. The objective of the fourth and final pilot study was to include all of the outcomes from the preceeding pilot studies and attempt a trial run of the actual data collection process. A study participant with no affiliation to the research project was used and a complete trial run was performed after which the measurement process was deemed feasible. In the primary study, 18 student volunteers completed a sequence of computer tasks, including keyboard, mouse and reading activities. Prior to data capture, full range of motion of the thoracic and cervical spines were measured in three dimensions for every participant. Data capture took place for the full duration of performance of all computer activities. Outcome parameters for postural dynamism included true range of motion (degrees), proportional range of motion (percentage) and motion frequency (movement per minute) in all three planes of motion of the cervical and thoracic spines. Typing tasks were associated with biggest movement ranges and motion frequencies. Mouse activity was associated with the most stationary posture, exhibiting the least frequent movement as well as the smallest ranges of motion. The results from this study allow us to better understand the dynamic nature of posture, as well as postural dynamism associated with different computer tasks. This study provides a baseline for future research of 3D motion analysis of the sitting posture. It also marks the need for further research regarding ergonomics, use and potential alternatives in the computer workstation and input devices.
AFRIKAANSE OPSOMMING: Hierdie studie het ten doel gehad om die meting van posturale dinamisme in die sitposisie te verbeter deur middel van „n drie-dimensionele (3D) bewegingsanalisesisteem. Die primêre doelwit was om loodsdata te beskryf vir posturale dinamisme van die servikale en torakale werwelkolomme terwyl op „n rekenaar gewerk word. Die sekondêre doelwit was om die proses van postuurmeting en analise te verfyn deur die dataprosesseringstyd te verminder. Sekere faktore van 3D bewegingsanalise kan „n vermeerdering van gapings in ingesamelde data tot gevolg hê, wat weer kan lei na „n verlengde tydperiode van dataprosessering. In die eerste fase van hierdie studie is sulke faktore identifiseer en aangepas. „n Reeks loodsstudies is uitgevoer om die verbetering van dataprosesseringstyd te toets namate aanpassings aan hierdie faktore gemaak is. Tydens die eerste twee loodsstudies is verskillende kamera en driepoot posisionering ondersoek en verfyn, werkstasie uitleg en anatomiese baken merker plasing is ondersoek en die optimale dataversamelingsfrekwensie is vasgestel. In beide hierdie loodsstudies is die uitkomste vasgestel op grond van toets- en fouteer deur te eksperimenteer met „n verskeidenheid opsies soos van toepassing op die betrokke uitkomste. Tydens die derde loodsstudie is rekenaarsagteware getoets wat die rekenaaraktiwiteit vir die studiedeelnemers verskaf het tydens primêre data-insameling. Twee onafhanklike persone het al die aktiwiteite volgens die sagteware voltooi en het verbale terugvoer en aanbevelings gegee oor hoe om die program te verbeter. Die vierdie en finale loodsstudie het gepoog om al die uitkomste van die eerste drie loodsstudies in te sluit en „n toetsmeting te doen van die ware dataversamelingsproses. „n Onafhanklike studiedeelnemer met geen affiliasie tot die navorsingsprojek nie het „n toetslopie van die hele versamelingsproses gedoen en die metingsproses is haalbaar verklaar. Tydens die primêre studie het 18 student-vrywilligers „n reeks rekenaartake gedoen (insluitend sleutelbord en muisaktiwiteite sowel as „n leesopdrag). Voor die aanvang van dataversameling is die volle bewegingsomvange van die torakale en servikale werwelkolomme van elke deelnemer gemeet. Dataversameling is vir die volle durasie van die uitvoer van rekenaaraktiwiteite gedoen. Uitkomsparameters vir posturale dinamisme het die volgende ingesluit: Omvang van beweging (grade), proporsionele omvang van beweging (persentasie) en bewegingsfrekwensie (bewegings per minuut) in al drie bewegingsvlakke van die servikale en torakale werwelkolomme. Sleutelbord-aktiwiteite is geässosieer met die grootste bewegingsomvange en die meeste bewegingsfrekwensie. Muisaktiwiteit is geässosieer met die mees stasionêre postuur en het die heel minste gereelde beweging getoon in die algemeen. Die resultate van hierdie studie help om die dinamise natuur van postuur beter te verstaan, sowel as posturale dinamisme wat met verskillende rekenaartake verbind word. Die studie bied „n basislyn vir die toekomstige navorsings wat posturale dinamisme met verskillende rekenaartake meet. Dit merk ook die behoefte aan verdere navorsing aangaande ergonomika, gebruik en alternatiewe tot rekenaarwerkstasie en –toerusting.
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Van, Vledder Nicole. "An ergonomic intervention : the effect of a chair and computer screen height adjustment on musculoskeletal pain and sitting comfort in office workers." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96865.
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Thesis (MScPhysio)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Aims: To assess the effect of a vertical height adjustment of the chair and visual display unit (VDU) on work related upper quadrant musculoskeletal pain (WRUQMP) and sitting comfort in computer users. The upper quadrant refers to the occiput, cervical and upper thoracic spine including the clavicles and scapulae. Methods: An N=1 study was conducted using the ABC design whereby an ergonomic workstation adjustment, of VDU and chair height, was compared to the subject’s usual workstation settings. Pain and sitting comfort were measured using visual analogue scales (VAS). The subject was assessed over the four week phases as she performed her typical VDU work. The results were compiled and tabulated. Results: Both the mean and variance in pain intensity decreased after the workstation intervention. A deterioration was noted in sitting comfort. Conclusion: The vertical height adjustment of the chair and VDU may have contributed to a decrease in WRUQMP in this subject. This safe, economical workstation intervention may be a practical management option for the computer user suffering from WRUQMP. Further research into the measurement of comfort whilst sitting at a computer workstation, is recommended.
AFRIKAANSE OPSOMMING: Doelwitte: Om die effek te bepaal van n vertikale aanpassing van die stoel en beeldskerm van rekenaargebruikers op werksverwandte boonste kwadrant muskuloskeletale pyn en sitgemak. Die boonste kwadrant verwys na die oksiput, servikale en boonste torakale werwelkolom en sluit ook die klavikel en skapula in. Methode: Die N=1 studie is onderneem met gebruik van die ABC ontwerp in terme waarvan n ergonomiese aanpassing van stoel en beeldskerm vergelyk is met die normale gebruik van die deelnemer. Pyn en sitgemak is gemeet deur die gebruik van die Visueel analoogskaal. Die interwensies is ge-evalueer oor vierweekfases tydens normale rekenaar gebruik van die deelnemer. Die resultate is saamgestel en getabuleer. Uitkoms: Beide die gemiddelde en veranderlike pynintensiteit het verminder nadat die werkstasie aangepas is. Geen verbetering in sitgemak is opgemerk nie. Gevolgtrekking: Die vertikale hoogte-aanpassing van die stoel en beeldskerm het moontlik bygedra tot die verminderde pynvlakke in hierdie deelnemer. Hierdie veilige, ekonomiese verstelling is moontlik n praktiese beheeropsie vir rekenaargebruikers wat werksverwandte boonste kwadrant muskuloskeletale pyn verduur. Verder studie in die meet en waarneming van sitgemak tydens rekenaarwerk is nodig.
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Lindegård, Andersson Agneta. "Associations between working techniques, physical loads and psychosocial loads during VDU-work /." Stockholm : Arbetslivsinstitutet, förlagstjänst, 2004. http://ebib.arbetslivsinstitutet.se/ah/2004/ah2004_05.pdf.
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Saggu, Rajinder Kaur. "Effect of a chair and computer screen height adjustment on the neck and upper back musculoskeletal symptoms in an office worker." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96971.
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Thesis (MScPhysio)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Aims: To assess the effect of a chair and computer screen height adjustment on the neck and upper back musculoskeletal symptoms in an office worker. Methods: An N=1 study was conducted using the ABC design. Ethics approval was obtained for the study and the participant provided informed written consent. The participant was assessed over three four week phases as she performed her habitual computer work. The outcome measures assessed during the three phases were the pain intensity and perceived sitting comfort. The three phases were named the baseline, intervention and wash-out phases. During the baseline phase, the outcome measures were obtained at the participant‟s habitual work station. The intervention phase involved a vertical adjustment of the chair and computer screen height. The wash-out phase allowed the participant to adjust the chair and computer screen height to their choice. A follow-up interview was conducted with the participant three months after completion of the study. The mean values and the ranges of the pain intensity and perceived comfort were obtained and compared. The data collected was captured on a Microsoft Excel 2010 spread sheet, where after the data was tabulated and presented graphically. Results: The mean pain intensity of the participant increased slightly during the intervention phase in comparison to the baseline phase, but remained stable during the wash-out phase. The mean perceived sitting comfort deteriorated initially during the intervention phase, but improved later during the intervention phase and showed greater improvement during the wash out phase. The perceived sitting comfort showed more improvement than the pain intensity during the washout phase. Both the pain intensity and perceived sitting comfort showed improvement at the three months follow up assessment, post completion of the study. Conclusion: The vertical height adjustment of the chair and the VDT did not improve the participant‟s pain intensity and perceived sitting comfort when compared to the participant‟s habitual workstation parameters. The findings do not favour the horizontal viewing angle. The findings of this study however support the use of „slightly below horizontal‟ viewing angle as being conducive to reduce the pain intensity and improve the sitting comfort of an office worker.
AFRIKAANSE OPSOMMING: Doelstelling: Om die effek te bepaal van die hoogte aanpassing van die stoel en rekenaarskerm op die nek en bo-rug muskuloskeletale simptome van 'n kantoorwerker. Metodes: „n N=1 studie was uitgevoer deur gebruik te maak van die ABC ontwerp. Etiese goedkeuring was verkry vir die studie en die deelnemer het ingeligte skriftelike toestemming verleen. Die deelnemer was ge-evalueer oor drie vier week-lange fases terwyl sy haar gewone rekenaarwerk verrig het. Die uitkomsmetings ge-evalueer tydens die drie fases was pyn intensiteit en waargenome sitgemak. Die drie fases was genoem die basislyn, intervensie en uitwas fases. Gedurende die basislyn fase was die uitkomsmetings by die deelnemer se gewone werkstasie ingevorder. Die intervensie fase het 'n vertikale aanpassing van die stoel en rekenaarskerm behels. Die uitwas fase het die deelnemer toegelaat om haar stoel en rekenaarskerm se hoogte aan te pas volgens haar keuse. 'n Opvolg onderhoud was gevoer met die deelnemer drie maande na die voltooiing van die studie. Die resultate was vasgelê op 'n Microsoft Excel 2010 data bladsy, waarna die data getabuleer en grafies uitgebeeld is. Resultate: Die gemiddelde pyn intensiteit van die deelnermer het effens toegeneem tydens die intervensie fase in vergelyking met die basislyn fase, maar het stabiel gebly tydens die uitwas fase. Die gemiddelde waargenome sitgemak het aanvanklik verswak tydens die intervensie fase, maar het later verbeter tydens die intervensie fase en het aangehou verbeter tydens die uitwas fase. Die waargenome sitgemak het groter verbetering getoon as die pyn intensiteit tydens die uitwas fase. Beide pyn intensiteit en waargenome sitgemak het verbetering getoon by die drie maande opvolg evaluasie, na voltooiing van die studie. Gevolgtrekking. Die vertikale hoogte aanpassing van die stoel en rekenaarskerm het nie die deelnemer se pyn intensiteit en waargenome sitgemak in vergelyking met die deelnemer se gewone werkstasie parameters verbeter nie. Hierdie bevindinge is nie ten voordeel van die horisontale kykhoek nie. Nietemin, ondersteun die bevindinge van hierdie studie die gebruik van die "effens onder die horisontale" kykhoek as bevorderend om die pyn intensiteit te verminder en die sitgemak van 'n kantoorwerker te verbeter.
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Lonne-Rahm, Sol-Britt. "Etiological and clinical aspects of skin sensitivity /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-746-0.
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Druin, Allison. "Building an alternative to the traditional computer terminal." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14966.
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McLean, Linda. "Neuromuscular electrophysiology and the computer terminal operator, the benefit of microbreaks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0004/NQ38351.pdf.
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Ding, Hao. "FOUR TERMINAL JUNCTION FIELD-EFFECT TRANSISTOR MODEL FOR COMPUTER-AIDED DESIGN." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3129.
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A compact model for four-terminal (independent top and bottom gates) junction field-effect transistor (JFET) is presented in this dissertation. The model describes the steady-state characteristics with a unified equation for all bias conditions that provides a high degree of accuracy and continuity of conductance, which are important for predictive analog circuit simulations. It also includes capacitance and leakage equations. A special capacitance drop-off phenomenon at the pinch-off region is studies and modeled. The operations of the junction fieldeffect transistor (JFET) with an oxide top-gate and full oxide isolation are analyzed, and a semi-physical compact model is developed. The effects of the different modes associated with the oxide top-gate on the JFET steady-state characteristics of the transistor are discussed, and a single expression applicable for the description of the JFET dc characteristics for all operation modes is derived. The model has been implemented in Verilog-A and simulated in Cadence framework for comparison to experimental data measured at Texas Instruments.Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering
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Alvarsson, Fredrik. "An interactive computer terminal about particle physics and the Atlas Experiment." Thesis, KTH, Fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189057.
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Wahlström, Jens. "Physical load, psychosocial and individual factors in visual display unit work /." Stockholm : Arbetslivsinstitutet, 2003. http://ebib.arbetslivsinstitutet.se/ah/2003/ah2003_10.pdf.
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Faxö, Elias. "Trusted terminal-based systems." Thesis, Linköpings universitet, Institutionen för systemteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69589.
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Trust is a concept of increasing importance in today’s information systems where information storage and generation to a higher extent is distributed among several entities throughout local or global networks. This trend in information science requires new ways to sustain the information security in the systems. This document defines trust in the context of a terminal-based system and analyzes the architecture of a distributed terminal-based system using threat modeling tools to elicit the prerequisites for trust in such a system. The result of the analysis is then converted into measures and activities that can be performed to fulfill these prerequisites. The proposed measures include hardware identification and both hardware and software attestation supported by the Trusted Computing Group standards and Trusted Platform Modules that are included in a connection handshake protocol. The proposed handshake protocol is evaluated against a practical case of a terminal-based casino system where the weaknesses of the protocol, mainly the requirement to build a system-wide Trusted Computing Base, are made evident. Proposed solutions to this problem such as minimization of the Trusted Computing Base are discussed along with the fundamental reason of the problem and the future solutions using the next generation of CPUs and Operating System kernels.
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Williams, Stanley Eugene. "Methods for storing, generating, and displaying characters to a graphics computer terminal." Virtual Press, 1987. http://liblink.bsu.edu/uhtbin/catkey/483079.
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This creative project investigates a method for translating a run-length encoded data file of letterforms into bit mapped images. Each letterform is broken (cracked) into primitive strokes. Each primitive stroke is represented by equally spaced runlength spline points within a 72 unit counting system. The strokes are ordered from left to right, allowing a direct scan-line conversion using an on-off character fill. Most commercial letterforms are stored in an outline format. Outline letterfomrs must be converted to vector edges, and then quick sorted into two dimensional arrays of edges for scan-line conversion (no overlapping outlines are allowed). The author's method stores primitives in a left to right ordered format that eliminates the sorting routine.In order to display the letterforms as a body of text, an interpreted description language was developed. The language command structure is embedded in the text file and interpreted at run time. The language controlls the sizing and placement of letterforms at five levels. The page attributes controlls the placement of page margins, column margins, windows, headers, footers, etc. The Paragraph attributes controlles first word indents, paragraph indents, widow lines, etc. The line attributes controlles the text line length, inter word and character spacing, line leading, additional line indents, type of line justification and hyphenation, etc. No attributes were established at the word level. The character attributes controlles the type size, type style, degree of slant (poor man's italic), expansion or contraction, etc.Ball State UniversityMuncie, IN 47306
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Liukkonen, E. (Esa). "Radiologisten kuvien katselussa käytettävien näyttöjen laatu:näyttöjen laitekanta, suorituskyky ja laadunvalvonta sekä kuvankatseluolosuhteet radiologisissa yksiköissä ja terveyskeskuksissa." Doctoral thesis, University of Oulu, 2010. http://urn.fi/urn:isbn:9789514262180.
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Abstract The purpose of this study was to investigate the quality of displays at radiology departments and healthcare centers, viewing conditions, quality control practices and user experiences of viewing radiological images from displays during 2007. The study aimed to provide guidelines to improving the quality of image viewing from displays and viewing conditions in healthcare. The data was gathered from radiology departments at university hospitals in Finland and healthcare centers in the treatment area of responsibility of the Oulu University Hospital. Display technology, quality control practices and users experiences of viewing were determined using questionnaires. Technical measurements were performed in order to acquire information on displays performance and viewing conditions. In addition, observation was used to evaluate viewing conditions. Almost all displays at radiological departments were applicable for diagnostics. At healthcare centers all displays were inapplicable for diagnostics. Both organization groups had displays using obsolete cathode ray tube technology and these displays did not pass current acceptance criteria. Most radiology departments had viewing conditions which were compatible with existing guidelines, whereas at healthcare centers lighting conditions were too bright for viewing radiological images from displays. Acceptance testing was done only for few of the displays and quality control was not performed regularly. Personnel responsible for quality assurance felt they were provided with inadequate resources for performing display quality control. Clinicians at healthcare centers did not identify the poor performance of displays. Radiologists and clinicians at healthcare centers rarely performed quality assurance for displays. The quality of displays, viewing conditions and the assessment of display performance at healthcare organizations was not at the level required by the existing guidelines. Both the cathode ray tube displays and uncalibrated liquid crystal displays should either be replaced with new ones or calibrated. Lighting and positioning of displays ought to be rearranged in order to diminish reflections. Furthermore, doctors ought to be able to rearrange lighting conditions with ease. More resources ought to be directed to display quality control and different quality control practices should be unified. Both the users and the quality control personnel should also be provided with more training in display quality control. Regular display quality control should be extended to all healthcare organizations. Clinicians working at healthcare centers should be provided with adequate training in the use of image viewing softwareTiivistelmä Tämän tutkimuksen tarkoituksena oli selvittää vuoden 2007 aikana radiologisten yksiköiden ja terveyskeskusten radiologisten kuvien katseluun tarkoitettujen näyttöjen laatu, kuvankatseluolosuhteet ja laadunvalvontakäytännöt sekä käyttäjien kokemuksia röntgenkuvien katselusta näytöiltä. Tutkimuksen tavoitteena oli antaa toimenpide-ehdotuksia kuvankatselun ja kuvankatseluolosuhteiden kehittämiseksi terveydenhuollossa. Aineisto muodostui otoksesta viiden yliopistollisen sairaalan radiologisista yksiköistä ja Oulun yliopistollisen sairaalan erityisvastuualueen terveyskeskuksista. Näyttöjen laitekanta, laadunvalvontakäytännöt ja lääkäreiden kokemuksia näyttötyöskentelystä selvitettiin kyselyllä. Mittausten ja havainnoinnin avulla saatiin tietoa näyttöjen suorituskyvystä ja kuvankatselutilojen valaistusolosuhteista. Radiologisten yksiköiden näytöt olivat teknisesti pääosin radiologisista kuvista tehtävään diagnostiikkaan soveltuvia. Terveyskeskuksissa käytettiin näyttöjä, jotka eivät soveltuneet diagnostiikkaan. Molemmissa ryhmissä poistuvaan katodisadeputkitekniikkaan perustuvia näyttöjä oli vielä käytössä, eikä yksikään mitatuista näytöistä saavuttanut hyväksyttävyyskriteereitä kaikkien suorituskyvyn mittaustulosten osalta. Suurimmassa osassa radiologisten yksiköiden työpisteissä huoneen valaistus oli suositusten mukainen, kun taas terveyskeskuksissa huoneiden valaistus oli liian voimakas radiologisten kuvien katseluun käytetyillä näytöillä. Vastaanottotarkastus oli tehty vain pienelle osalle näytöistä ja säännöllistä laadunvalvontaa tehtiin näytöille vähän. Laadunvalvojat kokivat resurssit riittämättömiksi näyttöjen laadunvalvontaan. Terveyskeskuslääkärit eivät itse tunnistaneet näytön huonoa suorituskykyä. Radiologit ja terveyskeskuslääkärit tekivät laadunvalvontaa käyttämilleen näytöille hyvin vähän. Tutkimuksen kohteena olleissa radiologisissa yksiköissä ja terveyskeskuksissa röntgenkuvien katseluun tarkoitettujen näyttöjen laatu, valaistusolosuhteet ja laadunvalvonta eivät vastanneet suosituksia. Katodisädeputkinäytöt ja kalibroimattomat nestekidenäytöt tulisi vaihtaa uusiin tai kalibroida. Valaistusta ja näyttöjen sijoittelua tulisi muuttaa heijastusten vähentämiseksi. Lisäksi lääkärillä tulisi olla mahdollisuus muuttaa valaistusta helposti. Näyttöjen laadunvalvontaan tulisi saada enemmän resursseja, laadunvalvontakäytännöt tulisi yhtenäistää ja käyttäjille sekä laadunvalvojille tulisi antaa lisää koulutusta näyttöjen laadunvalvontaan. Säännöllinen näyttöjen laadunvalvonta tulisi ulottaa kaikkiin terveydenhuollon organisaatioihin. Terveyskeskuslääkäreille tulisi antaa koulutusta kuvankatseluohjelmien käyttöön