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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Shift rotation selected physiological and psychological effects : a research report submitted in partial fulfillment ... /

Pilon, Christine E. Zang, Laura M. January 1976 (has links)
Thesis (M.S.)--University of Michigan, 1976.
52

Shift rotation selected physiological and psychological effects : a research report submitted in partial fulfillment ... /

Pilon, Christine E. Zang, Laura M. January 1976 (has links)
Thesis (M.S.)--University of Michigan, 1976.
53

Relationships Between Classroom Schedule Types and Performance on the Algebra I Criterion-Referenced Test

Murray, Gregory V. 01 December 2012 (has links)
Public education has options with regard to educational settings and structures. States and school districts may select varying lengths for the school year, lengths for the school day, and lengths for individual class periods. In Utah, one measure of students' achievement is scores on the State's end-of-level criterion-referenced test (CRT) for Algebra I. Additionally, an option regarding educational structures is the schedule type used to deliver Algebra I classes. This study examined the relationship between student achievement as measured by Algebra I CRT scores, and the schedule type used to deliver Algebra I classes. The schedule types compared were the traditional daily schedule, trimester 3/3 schedule, trimester 2/3 schedule, and the block A/B schedule. This study sought to answer two research questions: (1) What is the relationship between mathematics instructional schedule type and student scores on Utah's CRT for Algebra I, for all students? and (2) What is the relationship between mathematics instructional schedule type and student scores on Utah's CRT for Algebra I, by individual grade levels? Data were obtained from the Utah State Office of Education and included the scores for 50,000 Utah students, from over 300 different schools, who took the identical Algebra I CRT at the end of the 2010-2011 school year. Data were also obtained from each school district to determine the schedule type of each participating student. Both a multinomial logistic regression analysis and a t-test analysis were conducted to determine relationships between Algebra I CRT scores and schedule types. The results indicated significant differences in student achievement based on the schedule type overall and for individual grade levels. Generally, the earlier the grade level the higher the CRT score. Within individual grade levels, there were both statistically significant and nonsignificant differences. The schedule types that generally score the highest (trimester 3/3 and traditional) had more time in the mathematics classroom and the students' mathematics class met daily. The results suggest the value of daily time spent in the mathematics classroom and may assist educators when considering options available to foster student achievement.
54

A Development of Performance Metrics for Forecasting Schedule Slippage

Arcuri, Frank John 16 May 2007 (has links)
Project schedules should mirror the project, as the project takes place. Accurate project schedules, when updated and revised, reflect the actual progress of construction as performed in the field. Various methods for monitoring progress of construction are successful in their representation of actual construction as it takes place. Progress monitoring techniques clearly identify when we are behind schedule, yet it is less obvious to recognize when we are going to slip behind schedule. This research explores how schedule performance measurement mechanisms are used to recognize construction projects that may potentially slip behind schedule, as well as what type of early warning they provide in order to take corrective action. Such early warning systems help prevent situations where the contractor and/or owner are in denial for a number of months that a possible catastrophe of a project is going to finish on time. This research develops the intellectual framework for schedule control systems, based on a review of control systems in the construction industry. The framework forms the foundation for the development of a schedule control technique for forecasting schedule slippage — the Required Performance Method (RPM). The RPM forecasts the required performance needed for timely project completion, and is based on the contractor's ability to expand future work. The RPM is a paradigm shift from control based on scheduled completion date to control based on required performance. This shift enables forecasts to express concern in terms that are more tangible. Furthermore, the shift represents a focus on what needs to be done to achieve a target completion date, as opposed to the traditional focus on what has been done. The RPM is demonstrated through a case study, revealing its ability to forecast impending schedule slippage. / Master of Science
55

ENHANCED PRODUCTION PLANNING AND SCHEDULING METHOD FOR CONSTRUCTION PROJECTS

Qais Amarkhil (6616994) 05 July 2022 (has links)
<p>  </p> <p>Available literature indicated that construction projects have been experiencing significant time overruns from their planned duration. In many cases, the primary reasons for project delays were ineffective planning and scheduling methods, poor communication and collaboration between the key stakeholders, and the construction operations and task requirements have been overlooked.</p> <p>Construction project planning and scheduling are extensively studied topics, and several techniques have been developed to solve construction project scheduling problems. Traditional production planning and scheduling techniques are based on the push planning strategy, such as linear and network scheduling techniques. In the traditional method, the project scheduler calculates activity durations and then sequences them to determine when to complete the work. These techniques and planning methods have been criticized for lacking collaboration between project workers and realistic integration of the project time, location, and other essential resources to create a reliable work schedule. Furthermore, the inability to account for site operations, tasks, and workflow leads to waste and delay. </p> <p>Consequently, Ballard and Howell (1990) proposed the last planner system, and then Ballard et al. (2000) further developed the method. In the last planner system, all key stakeholders and the project management team actively communicate and coordinate to accomplish the project’s planned milestones. The last planner system and pull planning scheduling objective is improving workflow and increasing plan reliability. However, the pull planning scheduling method has some limitations. For instance, this method cannot be used to determine the available work capacity in each working space and show how much work can be completed at a given time. In addition, the pull planning and LPS system are highly descriptive and experienced-based, relying on the decision and experiences of the site supervisors. </p> <p>Available literature concerning construction project delay also indicated that ineffective planning and scheduling, slow decision-making, and poor communication and coordination had been the top critical causes of construction project delay.</p> <p>Therefore, this research was conducted to minimize construction project time and cost overrun due to poor scheduling and production planning. The study has been conducted in two main parts. In the first part of this study, critical causes of project delay have been analyzed, and the contribution of poor planning and scheduling to construction project delays in different environments has been assessed. The relative importance index and Spearman’s coefficient techniques have been utilized to analyze the collected data.  The second section of this research work was conducted to investigate the construction scheduling reliability and production efficiency and developed the enhanced production planning and scheduling method to improve schedule reliability and production plan efficiency.  The reason for developing the enhanced production planning and scheduling method was to find the best work option to optimize work duration and efficiently plan required resources per category of the identified activities. In addition, this study has automated the scheduling input data capturing from the project BIM model by utilizing the developed visual program.</p> <p>The study finding in the first section indicated that the top ten critical causes of identified causes of project delay in specified environments were significantly different. However, Ineffective project planning and scheduling had been among the most critical causes in all three conditions. Ineffective planning and scheduling were ranked number one in developed environment conditions, second in developing countries, and fifth in high-risk environments.</p> <p>Study results in the second section have shown that the case study's executed schedule had experienced significant changes in the planned dates of individual tasks, project milestones, and resource allocation. The project schedule critical path and critical activities were changed repeatedly after each update, and the project structure work was delayed for 30 days from its initial plan, as illustrated in figures 33 to 35. Subsequently, the enhanced planning methodology has been applied in the selected case study to validate the developed method and evaluate the result of the case study. The case study implemented work plan has been compared with the enhanced planning-based developed schedule. The total duration of the enhanced planning-based method has been calculated to be 240 work days, which shows 30 days less time from implemented case study plan and 50 days from the project base plan in the construction document, as illustrated in figures 39 to 41. </p> <p>Furthermore, the production schedule sensitivity analysis has shown that the production schedule and the case study base plan tasks duration have not been significantly different since both schedules were created based on the similar size of the work crew, but in terms of the number of the planned task, the production schedule had been created based on the most suitable work option. Another advantage of the production schedule is that it is more reliable because the schedule is created for a shorter duration, not long before the project work starts, and it is created after multiple collaborations and assessment steps. In addition, the developed program in this study using Revit dynamo automated the extraction of input data from the BIM model to create the project schedule. </p> <p>In conclusion, based on the case study results, the enhanced production planning methodology and developed metrics and indices can be applied to various building construction projects to find the most suitable work option and create a reliable and resource-efficient work schedule. </p>
56

Modelação e comportamento supersticioso: efeitos do comportamento do confederado sobre o responder em esquemas múltiplos / Modelling and superstitious behavior: effects on the behavior of the confederate responding in multiple schemas

Miranda, Sirlene Lopes de 19 November 2013 (has links)
A análise do comportamento mantido por relação acidental com reforço pode contribuir para a compreensão de episódios comportamentais em que pessoas superestimam suas capacidades de produzir alterações no ambiente. Adicionalmente, uma análise das contingências sociais e verbais contribui para uma compreensão mais clara do papel da expectativa na descrição de episódios do campo da ilusão ou distorção. O objetivo deste estudo foi avaliar o efeito do comportamento de um confederado sobre o responder de participantes em uma situação em que pontos são apresentados independentemente do comportamento. Quinze participantes, estudantes de ensino médio ou graduação, foram distribuídos em dois grupos: com e sem confederado. Em uma tarefa de computador, um retângulo colorido poderia ser pressionado utilizando-se o mouse. Esse retângulo aparecia de duas cores, sinalizando duas contingências diferentes. No grupo com a presença do confederado, participante e confederado iniciaram suas sessões ao mesmo tempo, em dois computadores diferentes, lado a lado, favorecendo ao participante ver o monitor do computador do confederado. O confederado respondia continuamente nos dois componentes enquanto o participante trabalhava em seu computador. Um grupo sem confederado permitiu avaliar o efeito do desempenho dos participantes em uma situação sem a presença do confederado. Os participantes de ambos os grupos foram expostos a duas condições experimentais: Na Condição Pontos Independentes, o participante recebia pontos independentemente do que fizesse em apenas um componente do esquema múltiplo (múltiplo VT EXT). Na condição Ausência de Pontos, pontos não eram apresentados em nenhum dos componentes (múltiplo EXT EXT). Após as sessões, os participantes deveriam estimar o controle sobre a produção dos pontos. Participantes do grupo com o confederado responderam em ambos os componentes cerca de oito vezes mais que os participantes do outro grupo, nas duas condições experimentais, resultado indicativo do efeito de controle social sobre o responder em esquemas múltiplos. Estimativas de controle dos participantes não foram consistentes com o desempenho não verbal dos participantes na tarefa, evidenciando controles sociais diferenciados em relação ao desempenho verbal e não verbal na tarefa / The behavior maintained by accidental relation with reinforcement can contribute to the understanding of behavioral episodes in which people overestimate their ability to produce changes in the environment. Additionally, an analysis of social and verbal contingencies contributes to a clearer understanding of the role of expectation in the description field of episodes of illusion or distortion. The aim of this study was to evaluate the behavior of a confederate on the participants response in a situation where points are presented regardless of the behavior. Fifteen participants - high school students and undergraduates - were divided into two groups- with and without the confederate. In a computer task a colored rectangle could be pressed using the mouse. This rectangle appeared in two colors, signaling two different contingencies. In the group with the presence of the confederate, participant and confederate began their sessions at the same time on two different computers side by side encouraging the participants to see the Confederates computer monitor. The Confederate responded continuously to the two components as the participant worked on his computer. By means of a group without the Confederate, it was possible to evaluate the effect of the participants performance in a situation without the presence of the confederate. Participants in both groups were exposed to two experimental conditions - in the Condition Points Independent, the participant received points regardless of what he did in just one component of the multiple schedule (multiple VT EXT). Provided Absence of Points, points were not presented in any of the components (multiple EXT EXT). After the sessions participants had to estimate the control over the production of the points. Group participants with the confederate responded in both components about eight times more than the other group of participants in the two experimental conditions, a result indicative of the effect of social control over responding in multiple schemas. Control estimates of the participants were not consistent with the performance of the participants in the nonverbal task showing different social controls over the performance in verbal and nonverbal task
57

Proposição de um método de nivelamento de recursos a partir de princípios da teoria das restrições para o planejamento operacional. / Propose one method of resource levelling developed using the principles of the theory of constraints to operational planning.

Akkari, Abla Maria Proência 17 April 2009 (has links)
O processo de planejamento de empreendimentos residenciais verticais no Brasil tem apresentado deficiências principalmente quanto do confronto das programações que balizam a decisão de investir, da tomada de risco do empreendimento, versus os resultados obtidos a partir do controle de sua implantação. As discrepâncias observadas entre o desempenho esperado na programação e aquelas obtidas nos processos de controle, principalmente quanto a indicadores de prazo e de alocação de recursos mostram a necessidade de se buscar sucessivos aprimoramentos dos processos da programação orientada a prazos. Aspectos como maior consistência no mapeamento de escopo na elaboração do planejamento operacional suportados por redes lógicas, além de uma adequada correlação entre as durações das atividades com as respectivas alocações e nivelamento de recursos merecem ser aprimorados. Uma abordagem para o desenvolvimento de programações operacionais, contemplando recursos para fazer frente aos aspectos acima citado se torna necessária. A ênfase se dá no estreitamento da correlação entre a estimativa das durações das atividades com as respectivas alocações de recursos. O objetivo deste trabalho é propor um método de nivelamento de recursos desenvolvido com o emprego de princípios da Theory of Constraints (TOC). O método de nivelamento consiste de regras heurísticas para programação operacional, complementado por procedimentos para o mapeamento de escopo e de uma biblioteca de redes lógicas elementares para edifícios residenciais verticais. Estes complementos têm por objetivo assegurar um nível mínimo de consistência e adequação do emprego do método de nivelamento ora proposto. Foram desenvolvidos 16 estudos de caso para suportar estes processos complementares, além de 171 testes em 21 redes lógicas para avaliar: os princípios da TOC, calibrar o método, analisar o seu desempenho e demonstrar sua aplicabilidade. Finalmente, concluiu-se que as regras heurísticas que compõem o método proposto nesta Tese são de fácil aplicação, e apresentaram desempenho igual ou superior as melhores regras existentes. / The planning process of construction of vertical housings used in Brazil have shown lacks, mainly when confronting the scheduling guiding the decision-making to invest, concerning the risk of the enterprise, versus the results obtained during the execution control. The discrepancies observed between the expected results regarding scheduling and those observed in the execution control processes, especially those about timeframe and resource allocation indicators, show the necessity to adjust and improve constantly the scheduling processes. Aspects such as greater consistency in defining scope and in the design of operational planning supported by logical networks, along with an appropriate correlation between the duration of activities and the corresponding resource allocation, deserve to be optimized. This study focus on the development of operational scheduling techniques, contemplating resource allocation to deal with those aspects above mentioned. Emphasis is given to the reinforcement of correlation between estimated timeframes for activities and the corresponding resource allocation. The objective of this research work is to propose one method of resource levelling developed using the principles of the Theory of Constraints (TOC). This method consists of a heuristic scheduling process oriented towards operational schedule, complemented by procedures for mapping of scope for the construction of vertical residential buildings and a library of elementary logical networks also oriented towards this type of buildings. The objective of these complements is to guarantee a minimum level of consistency for the simulated implementation model, as well as to insure the adequate use of the levelling resource process proposed here. Sixteen cases studies were developed to support these complementary processes, beyond 171 tests in twenty one logical networks to evaluate the principles of the TOC, to calibrate the method, to analyze its performance and to demonstrate its applicability. Finally, it was concluded that the heuristics rules proposal that compose the method in this Thesis is of easily application, and presented a performance equally or higher than the best existent rules.
58

Analysis of parabolic through collector cleaning system under adaptive scheduling policy

Turkoglu, Aykut 10 July 2017 (has links)
The purpose of this study is to investigate the effects of stochastic dust accumulations and rain events on the cleaning schedule of the parabolic trough collectors that are used to generate power at concentrated solar power (CSP) plants. The level of cleanliness is proportional to the power produced, and thus it affects the economic pay off at CSP plants. Current practice to address this dust problem, termed as conventional cleaning, is to follow a periodic cleaning schedule that entails a fixed setup cost for each cleaning event. The frequency of cleaning under such conventional (periodic schedule) policy is selected based upon a tradeoff between the set up cost and the payoff from improving the cleanliness factor. The conventional practice is to have a constant and periodic cleaning schedule over an entire season (e.g. either severe or mild combination of the dust and rain over a 180-day cleaning season, with either 8 or 4 cycles scheduled for the severe and mild seasons respectively). This thesis draws upon evidence from recent literature to show that presence of random rain events improves the cleanliness of parabolic troughs in CSP plants. Upon analyzing such evidence, this study models rain event as a compound Poisson process that replenishes the level of cleanliness. In this scenario, it is possible to establish an adaptive threshold policy for scheduling plant cleaning that analogous to the formulation of a (s,S) inventory management policy, subject to random replenishment of inventory. The study offers a review of related literature to establish that such formulations are not amenable to a close form solution. The second half of the thesis describes a numerical study that has been conducted using Arena Simulation package for characterizing the adaptive cleaning policy. The parameter of interest for assessing system performance is the average payoff over the average cost of cleaning for a 180-day cleaning season. Numerical study shows that adaptive cleaning policy outperforms the conventional (periodic) cleaning policy under reasonable assumptions for dust and rain event distributions. As an extension, the simulation study also examines the use of alternative cleaning system, known as electrodynamic screening (EDS), for different rain scenarios that may be used in conjunction with either conventional or adaptive cleaning policies to improve the overall system performance. / 2019-07-09T00:00:00Z
59

Modelação e comportamento supersticioso: efeitos do comportamento do confederado sobre o responder em esquemas múltiplos / Modelling and superstitious behavior: effects on the behavior of the confederate responding in multiple schemas

Sirlene Lopes de Miranda 19 November 2013 (has links)
A análise do comportamento mantido por relação acidental com reforço pode contribuir para a compreensão de episódios comportamentais em que pessoas superestimam suas capacidades de produzir alterações no ambiente. Adicionalmente, uma análise das contingências sociais e verbais contribui para uma compreensão mais clara do papel da expectativa na descrição de episódios do campo da ilusão ou distorção. O objetivo deste estudo foi avaliar o efeito do comportamento de um confederado sobre o responder de participantes em uma situação em que pontos são apresentados independentemente do comportamento. Quinze participantes, estudantes de ensino médio ou graduação, foram distribuídos em dois grupos: com e sem confederado. Em uma tarefa de computador, um retângulo colorido poderia ser pressionado utilizando-se o mouse. Esse retângulo aparecia de duas cores, sinalizando duas contingências diferentes. No grupo com a presença do confederado, participante e confederado iniciaram suas sessões ao mesmo tempo, em dois computadores diferentes, lado a lado, favorecendo ao participante ver o monitor do computador do confederado. O confederado respondia continuamente nos dois componentes enquanto o participante trabalhava em seu computador. Um grupo sem confederado permitiu avaliar o efeito do desempenho dos participantes em uma situação sem a presença do confederado. Os participantes de ambos os grupos foram expostos a duas condições experimentais: Na Condição Pontos Independentes, o participante recebia pontos independentemente do que fizesse em apenas um componente do esquema múltiplo (múltiplo VT EXT). Na condição Ausência de Pontos, pontos não eram apresentados em nenhum dos componentes (múltiplo EXT EXT). Após as sessões, os participantes deveriam estimar o controle sobre a produção dos pontos. Participantes do grupo com o confederado responderam em ambos os componentes cerca de oito vezes mais que os participantes do outro grupo, nas duas condições experimentais, resultado indicativo do efeito de controle social sobre o responder em esquemas múltiplos. Estimativas de controle dos participantes não foram consistentes com o desempenho não verbal dos participantes na tarefa, evidenciando controles sociais diferenciados em relação ao desempenho verbal e não verbal na tarefa / The behavior maintained by accidental relation with reinforcement can contribute to the understanding of behavioral episodes in which people overestimate their ability to produce changes in the environment. Additionally, an analysis of social and verbal contingencies contributes to a clearer understanding of the role of expectation in the description field of episodes of illusion or distortion. The aim of this study was to evaluate the behavior of a confederate on the participants response in a situation where points are presented regardless of the behavior. Fifteen participants - high school students and undergraduates - were divided into two groups- with and without the confederate. In a computer task a colored rectangle could be pressed using the mouse. This rectangle appeared in two colors, signaling two different contingencies. In the group with the presence of the confederate, participant and confederate began their sessions at the same time on two different computers side by side encouraging the participants to see the Confederates computer monitor. The Confederate responded continuously to the two components as the participant worked on his computer. By means of a group without the Confederate, it was possible to evaluate the effect of the participants performance in a situation without the presence of the confederate. Participants in both groups were exposed to two experimental conditions - in the Condition Points Independent, the participant received points regardless of what he did in just one component of the multiple schedule (multiple VT EXT). Provided Absence of Points, points were not presented in any of the components (multiple EXT EXT). After the sessions participants had to estimate the control over the production of the points. Group participants with the confederate responded in both components about eight times more than the other group of participants in the two experimental conditions, a result indicative of the effect of social control over responding in multiple schemas. Control estimates of the participants were not consistent with the performance of the participants in the nonverbal task showing different social controls over the performance in verbal and nonverbal task
60

Flexible Work Schedules, Virtual Work Programs, and Employee Productivity

Campbell, Kelley Marie 01 January 2015 (has links)
In a workplace marked by increasing change and competing commitments, business leaders require an increased understanding of alternative work programs. Utilizing spillover theory, motivator-hygiene theory, and adaptive structuration theory, this single case study was an exploration of the strategies that business leaders use for flexible work schedules and virtual work programs. The population consisted of 3 managerial business executives and 6 employees within a midwestern United States division of a global blood management solutions firm. The data collection process included a series of semistructured interviews, a focus group, and the assessment of company documentation. Methodological triangulation identified 5 emerging themes: program assessment and monitoring, standard set of virtual working hours, remote office setup, increased virtual communication, and promotion of quality of life. The transferability of this single case study remains with the reader and future researchers to determine. Future researchers may discover that the findings contribute to social change by better preparing organizations for success while simultaneously positioning individuals to attain optimum balance across life and work responsibilities.

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