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Journal articles on the topic "004.9:519.8"

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Starkova, A. V., Yu N. Karpenko, B. Ya Syropyatov, F. V. Sobin, and N. A. Pulina. "STUDY OF INFLUENCE OF BLOOD THIAZOLINE AMMONIUM 4-CHLOROPHENYL-2-HYDROXY-4-OXO-2-BUTENOATE CONCENTRATION ON ANTICOAGULANT EFFECT UPON SUBCUTANEOUS ADMINISTRATION." Perm Medical Journal 35, no. 1 (February 15, 2018): 88–94. http://dx.doi.org/10.17816/pmj35188-94.

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Aim. To study the effect of blood thiazoline ammonium 4-chlorophenyl-2-hydroxy-4-oxo-2-butenoate content on the manifestation of anticoagulant effect upon subcutaneous administration to rabbits. Materials and methods. The studies were fulfilled on outbred rabbits. The substance was administered subcutaneously in the dose of 35 mg/kg. The time of blood coagulation was determined using coagulometer “Minilab 701”, and blood concentration - by means of liquid micro-column chromatograph “Milichrom A-02”. Results. The obtained results prove that maximum concentration of the compound in blood and maximum anticoagulant effect is reached in 30 minutes after subcutaneous administration. The substance anticoagulant effect lasted for 120 minutes after its administration. At present, the compound concentration in blood is equal to 519.8 ± 145.41 ng/ml. Conclusions. The studied compound, when administered subcutaneously, is quickly absorbed and begins to render an anticoagulant effect. Efficacy of action of this compound depends on its blood concentration.
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Zulkurnai, N. Z., U. F. Md. Ali, N. Ibrahim, and N. S. Abdul Manan. "Carbon Dioxide Capture by Deep Eutectic Solvent Impregnated Sea Mango Activated Carbon." E3S Web of Conferences 34 (2018): 02030. http://dx.doi.org/10.1051/e3sconf/20183402030.

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The increment amount of the CO2 emission by years has become a major concern worldwide due to the global warming issue. However, the influence modification of activated carbon (AC) has given a huge revolution in CO2 adsorption capture compare to the unmodified AC. In the present study, the Deep Eutectic Solvent (DES) modified surface AC was used for Carbon Dioxide (CO2) capture in the fixed-bed column. The AC underwent pre-carbonization and carbonization processes at 519.8 °C, respectively, with flowing of CO2 gas and then followed by impregnation with 53.75% phosphoric acid (H3PO4) at 1:2 precursor-to-activant ratios. The prepared AC known as sea mango activated carbon (SMAC) was impregnated with DES at 1:2 solid-to-liquid ratio. The DES is composing of choline chloride and urea with ratio 1:2 choline chloride to urea. The optimum adsorption capacity of SMAC was 33.46 mgco2/gsol and 39.40 mgco2/gsol for DES modified AC (DESAC).
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Muggeridge, David J., Christopher C. F. Howe, Owen Spendiff, Charles Pedlar, Philip E. James, and Chris Easton. "The Effects of a Single Dose of Concentrated Beetroot Juice on Performance in Trained Flatwater Kayakers." International Journal of Sport Nutrition and Exercise Metabolism 23, no. 5 (October 2013): 498–506. http://dx.doi.org/10.1123/ijsnem.23.5.498.

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The aim of the current study was to determine the effects of dietary nitrate ingestion on parameters of submaximal and supramaximal exercise and time trial (TT) performance in trained kayakers. Eight male kayakers completed four exercise trials consisting of an initial discontinuous graded exercise test to exhaustion and three performance trials using a kayak ergometer. The performance trials were composed of 15 min of paddling at 60% of maximum work rate, five 10-s all-out sprints, and a 1 km TT. The second and third trials were preceded by ingestion of either 70 ml nitrate-rich concentrated beetroot juice (BR) or tomato juice (placebo [PLA]) 3 hr before exercise using a randomized crossover design. Plasma nitrate (PLA: 33.8 ± 1.9 μM, BR: 152 ± 3.5 μM) and nitrite (PLA: 519.8 ± 25.8, BR: 687.9 ± 20 nM) were higher following ingestion of BR compared with PLA (both p < .001). VO2 during steady-state exercise was lower in the BR trial than in the PLA trial (p = .010). There was no difference in either peak power in the sprints (p = .590) or TT performance between conditions (PLA: 277 ± 5 s, BR: 276 ± 5 s, p = .539). Despite a reduction in VO2, BR ingestion appears to have no effect on repeated supramaximal sprint or 1 km TT kayaking performance. A smaller elevation in plasma nitrite following a single dose of nitrate and the individual variability in this response may partly account for these findings.
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Rathod, Ramji, Faraat Ali, Amrish Chandra, Robin Kumar, Meenakshi Dahiya, and Gyanendra Nath Singh. "Simultaneous Determination of Alogliptin, Linagliptin, Saxagliptin, and Sitagliptin in Bulk Drug and Formulation by UPLC Q-TOF-MS." Current Pharmaceutical Analysis 17, no. 1 (November 23, 2020): 95–105. http://dx.doi.org/10.2174/1573412915666190708162012.

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Background: A simple and sensitive Ultra Performance Liquid Chromatography-Mass Spectrometry method was developed and validated to measure the concentrations of Alogliptin (ALO), Linagliptin (LIN), Saxagliptin (SAX), and Sitagliptin (SIT) using Pioglitazone (PIO) as an internal standard. Methods: Chromatographic separation of six gliptins was achieved on a C-18 column (100×2.1 mm, 2.7 μm) using a mobile phase consisting of formic acid in water, 0.1%v/v: acetonitrile in gradient elution. Electrospray ionization (ESI) source was operated in the positive ion mode. Targeted MS/MS mode on a QTOF MS was used to quantify the drug utilizing the transitions of 340.1(m/z), 473.2 (m/z), 316.2 (m/z), 408.1 (m/z), and 357.1 (m/z) for ALO, LIN, SAX, SIT and PIO respectively. Results: As per ICH Q2R1 guidelines, a detailed validation of the method was carried out and the standard curves were found to be linear over the concentration ranges of 1516.0-4548.1 ng mL-1, 519.8- 1559.4 ng mL-1, 1531.4-4594.3 ng mL-1and 1519.6-4558.8 ng mL-1 for ALO, LIN, SAX and SIT respectively. Precision and accuracy results were within the acceptable limits. The mean recovery was found to be 98.8 _ 0.76 % (GEM), 102.2 _ 1.59 % (LIN), 95.3 _ 2.74 % (SAX) and 99.2 _ 1.75 % (SIT) respectively. Conclusions: The optimized validated UPLC QTOF-MS/MS method offered the advantage of shorter analytical times and higher sensitivity and selectivity. The optimized method is suitable for application in quantitative analysis of pharmaceutical dosage forms for QC laboratory.
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Ramírez-Soto, Max Carlos, and Gutia Ortega-Cáceres. "Analysis of Excess All-Cause Mortality and COVID-19 Mortality in Peru: Observational Study." Tropical Medicine and Infectious Disease 7, no. 3 (March 5, 2022): 44. http://dx.doi.org/10.3390/tropicalmed7030044.

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During the COVID-19 pandemic, an excess of all-cause mortality has been recorded in several countries, including Peru. Most excess deaths were likely attributable to COVID-19. In this study, we compared the excess all-cause mortality and COVID-19 mortality in 25 Peruvian regions to determine whether most of the excess deaths in 2020 were attributable to COVID-19. Excess deaths were calculated as the difference between the number of observed deaths from all causes during the COVID-19 pandemic (in 2020) and the number of expected deaths in 2020 based on a historical from recent years (2017–2019). Death data were retrieved from the Sistema Informatico Nacional de Defunciones (SINADEF) at the Ministry of Health of Peru from January 2017 to December 2020. Population counts were obtained from projections from Peru’s Instituto Nacional de Estadística e Informática (INEI). All-cause excess mortality and COVID-19 mortality were calculated by region per 100,000 population. Spearman’s test and linear and multiple regression models were used to estimate the correlation between excess all-cause mortality and COVID-19 mortality per 100,000 population. Excess all-cause death rates varied widely among regions (range: 115.1 to 519.8 per 100,000 population), and COVID-19 mortality ranged between 83.8 and 464.6 per 100,000 population. There was a correlation between the all-cause excess mortality and COVID-19 mortality (r = 0.90; p = 0.00001; y = 0.8729x + 90.808; R2 = 0.84). Adjusted for confounding factors (mean age in the region, gender balance, and number of intensive care unit (ICU) beds), the all-cause excess mortality rate was correlated with COVID-19 mortality rate (β = 0.921; p = 0.0001). These findings suggest that most of the excess deaths in Peru are related to COVID-19. Therefore, these findings can help decision-makers to understand the high COVID-19 mortality rates in Peru.
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Čabaravdić, Azra, Aida Ibrahimspahić, Merisa Osmanović, and Mirsada Starčević. "EVALUATION OF MLR AND GWR REGRESSION MODELS OF CURRENT ANNUAL INCREMENT PREDICTED BY GROWING STOCK, TOPOGRAPHICAL AND LANDSAT 8 SPECTRAL DATA IN THE NORTHEAST BOSNIAN MIXED FOREST." Radovi Šumarskog fakulteta Univerziteta u Sarajevu 46, no. 2 (December 1, 2016): 10–25. http://dx.doi.org/10.54652/rsf.2016.v46.i2.70.

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UDK: 630*52/*56:519.8(497.6) The aim of this research was to evaluate estimates of the current annual increment of volume (CAIv) variability considering growing stock (V) as structural variable and topographic conditions and Landsat 8 spectral response as environmental variables on hilly and mountainous mixed forests in the northeast Bosnia using multiple linear regressions based on ordinary least squares (MLR) and geographically weighted regression (GWR). Sample data contains geo-referenced forest inventory data, CAIv (m3/ha/year) and V (m3/ha), extracted values from digital terrain model (altitude, slope and aspect) and derived principal components values from Landsat 8 satellite image for forest stands of the management unit located on hilly and mountain positions in protected area Konjuh, Kladanj. Here are applied MLR and GWR using stepwise procedure. MLR and GWR analyses resulted with global coefficients of significant predictors on hilly position. This was expected due to homogenous vegetation and environmental conditions on hilly position. It was found that growing stock affected CAIv the most. Significant improvement of regression modeling is achieved by GWR appliance on sample from mountainous position. There were obtained local influence of growing stock and the first principle component related to green biomass on CAIv. The highest improvement is found for broadleaves CAIv where quantification of local variability of growing stock increased adjusted coefficient of determination about 11% and reduced relative root mean square error for 6%. Local character of green biomass related to conifers CAIv did not improve regression estimation significantly. The broadleaves root mean square error based on GWR was 1.60 m3/ha/year (coefficient of variation more than 30%) which is still high so further modeling including other structural characteristics (stems number, basal area, mixture) as predictors is required.
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Kuei, Nina, Niren Patel, Hongyan Xu, Leigh Wells, Latanya Bowman, Pritam Bora, Kavita Natrajan, and Abdullah Kutlar. "Characteristics and Potential Biomarkers for Chronic Pain in Patients with Sickle Cell Disease." Blood 126, no. 23 (December 3, 2015): 986. http://dx.doi.org/10.1182/blood.v126.23.986.986.

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Abstract Vaso-occlusive episodes (VOE) or pain crises are a hallmark of sickle cell disease (SCD), with increasing recognition that a significant portion of SCD patients develop chronic pain. In the landmark PiSCES study (Smith et al), patients reported pain on 55% days, with ~30% reporting pain on >90% days. Thus, the episodic, nociceptive pain (VOE) in younger patients, evolves into a chronic pain syndrome, with neuropathic and centralized components in some adults. Kutlar et al (Blood, 2014), reported on the association of different pain related phenotypes (pain diaries, frequency of hospitalizations/ED visits, pressure pain threshold) with polymorphisms in candidate genes in 167 SCD patients, providing evidence that multiple signaling pathways and mechanisms are likely involved. In this study, 12 SCD subjects with "chronic pain", defined by reported pain >50% of days in pain diaries collected over 6 months, were enrolled (SCD-CP). 17 SCD patients who did not have chronic pain (SCD-NCP), and 9 non-SCD African-Americans (C) were enrolled as controls. Informed consent was obtained. Age, gender, Hb F levels, HU usage, and pressure pain algometer readings were recorded from SCD subjects. 8 ml of blood (EDTA) was collected from subjects at "steady state" and from normal controls. Plasma was separated and kept at -80 C until the assay. Plasma tryptase and Substance P levels were assayed by ELISA using kits from Biomatik, Inc. (catalog # EKU07922) and Enzo Life Sciences (Catalog #ADI-900-018), respectively. SCD-CP patients were significantly older than SCD-NCP: mean age 41 vs 32.2 (p=0.033). The pressure pain algometer readings did not differ significantly between SCD-CP and SCD-NCP at three sites (trapezius, ulna, masseter, p= 0.67-0.74). There were 12/17 patients on HU (70.6%) among SCD-NCP, and 6/12 (50%) among SCD-CP (p=0.435). Similarly, Hb F levels were not significantly different (14.7% in SCD-CP, vs 11.7% in SCD-NCP, p=0.446). Opioid use (average morphine equivalent as mg/day) was significantly higher in the chronic pain group (11.45 mg/day, vs 2.92 mg/day, p=0.015). Plasma tryptase and substance-P levels are shown in the table: Table 1. Tryptase (pg/ml) Substance-P (pg/ml) SCD-CP 1388.6 ±519.8 7221.1±7742.7 SCD-NCP 1023.64±221.04 5983.1±3473.0 Control 768.9±416.16 3939.7±1350.1 The difference in substance-P levels did not reach significance across groups by ANOVA (p=0.337) or in pairwise comparison between groups. However, tryptase levels were significantly different across groups by ANOVA (p=0.00615). Pairwise comparisons between two groups showed that tryptase levels were significantly different between SCD-CP and controls (p=0.0053). These results highlight characteristics of SCD patients with chronic pain: they are older, have a higher use of opioids, and have significantly higher tryptase levels. These observations support previous findings that age is a significant factor in transition to chronic pain in SCD. Higher dose of opioid use in SCD-CP could result from dose escalation to control pain; conversely, it could be argued that higher opioid use itself could be a factor in development of chronic pain through opioid-induced hyperalgesia. To our knowledge, this is the first study of plasma tryptase levels in SCD, in relation to different pain phenotypes. Tryptase is released into plasma with degranulation of mast cells and leads to inflammation, anaphylaxis, urticaria, and neuropathic pain. It binds PAR2 (protease activated receptor 2), releasing inflammatory mediators and substance P, inducing neurogenic inflammation. Elevated tryptase levels are found in systemic mastocytosis, and the newly recognized Mast Cell Activation Syndrome (MCAS). Vincent et al (Blood, 2013) showed that mast cell activation played an important role in neurogenic inflammation and chronic pain in a mouse model of SCD. They also demonstrated that inhibition of mast cell activation, via c-kit knockout or with imatinib or cromolyn sodium improved neurogenic inflammation and chronic pain. Two recent case reports (Murphy et al, Stankovic et al) document significant improvement in pain in SCD patients who developed CML, during treatment with imatinib. These observations, and the findings of our pilot study, not only suggest a novel mechanism and biomarker for chronic pain in SCD, but also a potential therapeutic target by inhibition of mast cell activation via c-kit pathway, or stabilization with cromolyn. Disclosures No relevant conflicts of interest to declare.
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Бавольська, Оксана, and Андрій Васильєв. "КОРЕКЦІЯ ПСИХОФІЗИЧНОГО РОЗВИТКУ ДІТЕЙ ІЗ ОСОБЛИВИМИ ОСВІТНІМИ ПОТРЕБАМИ ЗАСОБАМИ ДОПОВНЕНОЇ РЕАЛЬНОСТІ ІНТЕРАКТИВНОЇ ПЛАТФОРМИ BRIOLIGHT." "Вересень" 1, no. (88) (November 2, 2021). http://dx.doi.org/10.54662/veresen.1.2021.07.

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У статті висвітлено застосування інструментів інтерактивної платформи Briolight, як ефективного засобу корекції порушень психофізичного розвитку дітей з особливими освітніми потребами. Застосування інтерактивних інструментів Briolight ґрунтується на положеннях комплексного залучення провідних аналізаторів. Визначено основні характеристики інструментів та зміст означеної технології. Розкрито особливості використання таких інструментів інтерактивної платформи Briolight: інтерактивна підлога, інтерактивна стіна, інтерактивна пісочниця, інтерактивна панель, комплекс розвитку великої моторики, комплекс розвитку дрібної моторики, інтерактивне логопедичне дзеркало, інтерактивний метроном, інтерактивні гіроскопи, тощо. Обґрунтовано доречність застосування інструментів інтерактивної платформи Briolight в корекційно-розвитковій роботі з дітьми, які мають порушення психофізичного розвитку. Окреслено функції педагога, який застосовує цю технологію в корекційно-розвитковій роботі. Означено перспективи в поглибленому й детальному дослідженні ефективності застосування даного інструменту під час підвищення кваліфікації педагогічних працівників закладів освіти та інклюзивно-ресурсних центрів. УДК 376:004.9:159.93:378.046.4
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Lafuze, Joan Esterline, and Debra Dunlap Runshe. "Using open source technology to enhance nursing students’ understanding of physiology." FASEB Journal 26, S1 (April 2012). http://dx.doi.org/10.1096/fasebj.26.1_supplement.519.8.

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Martin, Mike, and Timothy Lyden. "Effects of aspirin on melanogenesis in B16F10 cells grown as 3D hanging drop tumor organoids." FASEB Journal 32, S1 (April 2018). http://dx.doi.org/10.1096/fasebj.2018.32.1_supplement.519.8.

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Dissertations / Theses on the topic "004.9:519.8"

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Leonenko, Ganna. "Transient solution of the M/Ek." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/56015/.

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In this thesis, the Erlang queueing model Af/i/l, where customers arrive at random mean rate A and service times have an Erlang distribution with parameter k and iro service rate u, has been considered from different perspectives. Firstly, an analytic metl of obtaining the time-dependent probabilities, pn,,(() for the M/Ek/l system have t> proposed in terms of a new generalisation of the modified Bessel function when initk there are no customers in the system. Results have been also generalised to the case wl initially there are a customers in the system. Secondly, a new generalisation of the modified Bessei function and its generating function have been presented with its main properties and relations to other special functii (generalised Wright function and Mittag-Leffler function) haw been noted. Thirdly, the mean waiting tune in the queue, H',(f), has been evaluated, using Lucha results. The double-exponential approximation of computing Yq(t) has been proposed different values of p. which gives results within about % of the 'exact1 values obtained fr numerical solution of the differential-difference equations. The advantage of this approximation is that it provides additional information, via its functional form of the characterisl of the transient solution. Fourthly, the inversion of the Laplace transform with the application to the queues 1 been studied and verified for A//A//1 and M/Ek/l models of computing Wq{t}. Finally, an application of the A//fi/l queue has been provided in the example of hour traffic flow for the Severn Bridge. One of the main reasons for studying queue models from a theoretical point of view is to develop ways of modelling real-life system. The analytic results have been confirmed with the simulation.
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Jones, Mari. "Modelling activities in a Critical Care Unit." Thesis, Cardiff University, 2008. http://orca.cf.ac.uk/54919/.

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The Critical Care Unit (CCU) is the sector of the hospital where, as the name suggests, critically ill patients receive treatment. The main aim of this research is to identify and apply suitable Operational Research techniques to model patient flow in the CCU at the University Hospital of Wales, Cardiff. The Operational Research techniques employed in this thesis include queueing theory and simulation. These methods have been utilised previously in the field of healthcare with much success. The thesis begins by considering two aspects of queueing theory, namely batch service queueing theory and batch arrival queueing theory. The latter of these is utilised to model patient flow within the CCU. Although queueing theory may be used as a good approximation to activities in the Unit, it does not incorporate all aspects of real-life. Thus discrete-event simulation is suggested as an alternative approach. Two types of statistical analysis, CART and Regression, are applied to both length of stay and mortality variables. The results from these statistical tests are compiled and investigated in more depth. Finally, a discrete event simulation model is built in Visual Basic for Applications, for Microsoft Excel. This simulation model incorporates many of the complexities of a CCU, such as patient priority and cancellation of scheduled patients if all beds on the Unit are occupied. The model is then used to test various "what-if type" scenarios, including the possibility of funding additional beds, the concept of ring-fencing of beds for different levels of care, and the likely effect of reducing the impact of bed-blocking.
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Komenda, Izabela. "Modelling critical care unit activities through queueing theory." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/47686/.

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Critical Care Units (CCUs) are one of the most complex and expensive of all medical resources and hospital managers are challenged to meet the demand for critical care services with adequate capacity. The pressure on critical care beds is continuously increasing as new medical equipment provides the opportunity to save more patients lives. It is therefore crucial that beds are managed well and used efficiently. This thesis describes two major projects, the first undertaken in conjunction with the CCU at the University Hospital of Wales in Cardiff (UHW); and the second with two CCUs from the Aneurin Bevan Health Board. In the first project data has been analysed to determine the flow of patients through the Unit. Admissions to CCUs were categorised under two headings: emergency, and elective. The length of stay in the CCU is heavily dependent on the admission category. In this thesis, both computer simulation and theoretical queueing models have been considered, which show how improvements in bed management may be achieved by considering these two categories of patients separately. The vast majority of previous literature in this field is concerned only with steady-state conditions, whereas in reality the processes are time-dependent. This thesis goes some way to addressing this deficiency. The second project relates to work undertaken with managers from the Royal Gwent Hospital in Newport and at the Nevill Hall Hospital in Abergavenny. Data from both hospitals have been analysed to define arrival and service processes. A state-dependent theoretical queueing model has been considered which has been used to investigate the significance of combining the two units. The model has been also utilised to advise on the number of beds the new combined unit should have in order to satisfy targets quoted by the hospital managers. In the final part of the thesis, consideration has been given to the impact of collaboration, or lack thereof, between hospitals using a game theoretical approach. The effect of patient diversion has been studied. To formally investigate the impact of patients transfers, a Markov chain model of the two CCUs has been set-up, each admitting two arrival streams: namely, their own patients and transfers from other hospital. Four different models were considered and for each model the effect of targets, demand and capacity were studied. The efficiency of a system which degrades due to selfish behaviour of its agents has been measured in terms of Price of Anarchy.
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Vile, Julie. "Time-dependent stochastic modelling for predicting demand and scheduling of emergency medical services." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/43186/.

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As the prominence of the service sector is increasing in developed nations, new and exciting opportunities are arising for operational researchers to develop and apply models which offer managers solutions to improve the quality of their services. The development of time-dependent stochastic models to analyse complex service systems and generate effective personnel schedules are key to this process, enabling organisations to strike a balance between the provision of a good quality service whilst avoiding unnecessary personnel costs. Specifically within the healthcare sector, there is a need to promote efficient management of an Emergency Medical Service (EMS), where the probability of survival is directly related to the speed of assistance. Motivated by case studies investigating the operation of the Welsh Ambulance Service Trust (WAST), this thesis aims to investigate how operational research (OR) techniques can be developed to analyse priority service systems subject to demand that is of an urgent nature, cannot be backlogged, is heavily time-dependent and highly variable. A workforce capacity planning tool is ultimately developed that integrates a combination of forecasting, queueing theory, stochastic modelling and optimisation techniques into a single spreadsheet model in order to predict future demand upon WAST, set staffing levels, and optimise shift schedules and rosters. The unique linking together of the techniques in a planning tool which further captures time-dependency and two priority classes enables this research to outperform previous approaches, which have generally only considered a single class of customer, or generated staffing recommendations using approximation methods that are only reliable under limited conditions. The research presented in this thesis is novel in several ways. Primarily, the first section considers the potential of a nonparametric modelling technique known as Singular Spectrum Analysis (SSA) to improve the accuracy of demand forecasts. Secondly, the main body of work is dedicated to adapting numerical queueing theory techniques to accurately model the behaviour of time-dependent multi-server priority systems across shift boundaries and evaluate the likelihood of excessive waits for service for two customer classes. The final section addresses how shifts can be optimally scheduled using heuristic search techniques. The main conclusions are that in addition to offering a more flexible approach, the forecasts generated by SSA compare favourably to those obtained using traditional methods, and both approximate and numerical modelling techniques may be duly extended to set staffing levels in complex priority systems.
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Shone, Robert William. "Optimal control of queueing systems with multiple heterogeneous facilities." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/71359/.

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This thesis discusses queueing systems in which decisions are made when customers arrive, either by individual customers themselves or by a central controller. Decisions are made concerning whether or not customers should be admitted to the system (admission control) and, if they are to be admitted, where they should go to receive service (routing control). An important objective is to compare the effects of "selfish" decision-making, in which customers make decisions aimed solely at optimising their own outcomes, with those of "socially optimal" control policies, which optimise the economic performance of the system as a whole. The problems considered are intended to be quite general in nature, and the resulting findings are therefore broad in scope. Initially, M/M/1 queueing systems are considered, and the results presented establish novel connections between two distinct areas of the literature. Subsequently, a more complicated problem is considered, involving routing control in a system which consists of heterogeneous, multiple-server facilities arranged in parallel. It is shown that the multiple-facility system can be formulated mathematically as a Markov Decision Process (MDP), and this enables a fundamental relationship to be proved between individually optimal and socially optimal policies which is of great theoretical and practical importance. Structural properties of socially optimal policies are analysed rigorously, and it is found that 'simple' characterisations of socially optimal policies are usually unattainable in systems with heterogeneous facilities. Finally, the feasibility of finding 'near-optimal' policies for large scale systems by using heuristics and simulation-based methods is considered.
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Poloczek, Felix. "Stochastic network calculus with martingales." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/89853/.

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The practicality of the stochastic network calculus (SNC) is often questioned on grounds of looseness of its performance bounds. The reason for its inaccuracy lies in the usage of too elementary tools from probability theory, such as Boole’s inequality, which is unable to account for correlations and thus inappropriate to properly model arrival flows. In this thesis, we propose an extension of stochastic network calculus that characterizes its main objects, namely arrival and service processes, in terms of martingales. This characterization allows to overcome the shortcomings of the classical SNC by leveraging Doob’s inequality to provide more accurate performance bounds. Additionally, the emerging stochastic network calculus with martingales is quite versatile in the sense that queueing related operations like multiplexing and scheduling directly translate into operations of the corresponding martingales. Concretely, the framework is applied to analyze the per-flow delay of various scheduling policies, the performance of random access protocols, and queueing scenarios with a random number of parallel flows. Moreover, we show our methodology is not only relevant within SNC but can be useful also in related queueing systems. E.g., in the context of multi-server systems, we provide a martingale-based analysis of fork-join queueing systems and systems with replications. Throughout, numerical comparisons against simulations show that the Martingale bounds obtained with Doob’s inequality are not only remarkably accurate, but they also improve the Standard SNC bounds by several orders of magnitude.
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Є, Чуб Г. "Математична модель біомедичних процесів." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/50704.

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1. Введение в математическое моделирование: учеб. Пособие для вузов/ [В.Н.Ашихмин, М.Г. Бояршинов, М.Б. Гитман и др.]; под ред. П.В. Трусова – М.: Интермет инжиниринг. 2000. – 336с.
Моделювання в медицині є цінним інструментом планування та оцінки втручань, особливо коли клінічне випробування є етично або логістично неможливим. Розробка таких математичних моделей, що використовуються для моделювання медичних результатів, стає все більшим напрямком у медицині.
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Ф, Покотун І. "Математичний підхід до оцінки ефективності реклами." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/50712.

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1. Росситер Дж. Р. Реклама и продвижение товара / Дж. Росситер. — СПб.: ПИТЕР, 2000. 2. Международный кодекс рекламной практики / Пер. с англ. Н. В. Гениной, В. Е. Демидова. — К.: Укрреклама, 2005. 3. Миронов Ю. Основи рекламної діяльності: навч. Посібник / Ю.Б. Миронов, Р.М. Крамар – Дрогобич: Посвіт, 2007. – 108 с.
Методи визначення ефективності реклами. – надзвичайно важливий фактор існування та розвитку підприємства в сучасному світі. Рекламна діяльність є основною умовою ефективної та прибуткової діяльності, вона постійно удосконалюється як незалежна структура з конкретними функціями й цілями.
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М, Яцун Б. "Математична модель розміщення парку повітряних суден по рейсам." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/50706.

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1. Вітлінський В. В. Ризикологія в економіці та підприємництві: [монографія] / В. В. Вітлінський, Г. І. Великоіваненко. – К.: КНЕУ, 2004. – 480 с. 2. Давиденко Н. М. Оцінювання ефективності корпоративного управління акціонерними товариствами / Н. М. Давиденко // Вісник Львівської комерційної академії. Серія: Економічна. – 2011. – Вип. 35. – С. 108–111.. 3. Комаристый Е.Н. Математические подходы к анализу спроса на пассажирские авиаперевозки / Маркетинг и маркетинговые исследования, №3 (51), июнь 2004, стр. 10-16.
Починаючи з середини минулого століття, індустрія авіаперевезень знаходиться на передньому краю використання методів автоматизованого планування та управління. Це пояснюється структурою завдань що утворюються, яка дозволяє формалізувати їх в рамках розроблених методів. До теперішнього часу сформований цілий комплекс завдань оптимального планування авіаційних операцій і підходів до їх вирішення.
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С, Кочерещенко В. "Застосування основних прийомів комбінаторики у процесі проектування." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/50718.

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1. Підручник з Трудового навчання. 8 клас / І.Ю. Ходзицька, В.П. Тименко, О.В. Горобець, О.І. Безносюк, Т.С. Пасічна, 2016. –142 с. 2. Трудове навчання 8 клас / Т.С. Мачача, Т.В. Стрижова, 2016. –177-182 с. 3. Трудове навчання 6 клас (для хлопців) / В.К. Сидоренко, 2014. –180-183 с.
У повсякденні нас оточує нескінченна кількість об’єктів різноманітних форм. При цьому світу, у якому ми живемо, притаманна економність, тобто багато форм є поєднанням одних тих самих елементів. До природного формоутворення близький такий метод проектування, як комбінаторика.
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