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FIALLOS, HUETE ANTONIO JOSE. "Adative correlation time window." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121290.
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Event correlation plays a key role in network management. It is the ability in networkmanagement systems to co-relate events by reading into event attributes and extractingmeaningful information that has value to network operators. It is a conceptual interpretation ofmultiple events such that a new meaning is assigned to these events. This interpretation is usedto pinpoint the events that are behind a root cause incident. The root cause could be a faultynode or an underperforming link. Understanding correlation patterns can potentially helpidentify and localize the root cause of a problem in a network so that network operators takenecessary actions to issue restoration operations. An important technique used by event correlators is temporal correlation of events,whereby events closely related in time with each other are correlated. This technique uses acorrelation time window as an interval in time to capture and correlate events. Traditionally,event correlators have used a fixed-sized correlation time window to perform event correlationin which the size of the correlation time window is fixed. However, this does not scale properlyin modern networks where dynamic relationships are commonplace. To address this issue, thisthesis presents and discusses the idea of an adaptive correlation time window, whereby thewindow size is dynamically calculated based on observable network conditions and processingtimes. The aim of the investigation is to explore the performance of an adaptive window inseveral network scenarios and, more importantly, to compare both types of windows in termsof their performance. To do this, several experiments were designed and performed on avirtualized network test bed. The results of such experiments demonstrate that the adaptivecorrelation time window adequately adapts to varying network conditions. The investigationalso shows the conditions that need to be fulfilled in order to observe a better performance ofeither type of window.
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Chang, Chia-We. "Continuous Shortest Path Problems with Time Window Constraints." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq24104.pdf.
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Haddara, A. A. "MUITS : a multi-window for Time-sharing Systems." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305351.
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Aleu, Bonaut Aitziber. "Stentriever thrombectomy for stroke within and beyond the time window." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/393973.
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Recientemente se ha aprobado el tratamiento endovascular(TEV) para el ictus por oclusión de gran vaso, lo cual ha cambiado radicalmente el pronóstico infausto de estos pacientes. Una de las contraindicaciones para el TEV es que el paciente llegue más alá de la ventana terapéutica (VT), que tradicionalmente era de 8 horas y actualmente es de 6 horas. La VT se define como el tiempo transcurrido desde el inicio de los síntomas hasta la punción femoral. En pacientes en quienes el inicio del ictus es desconocido, bien porque ocurrió durante el sueño o bien porque el paciente no puede decirlo y no había testigos, la hora de inicio se considera la última vez que el paciente fue visto bien. Estos pacientes caen fuera de VT porque llegan demasiado tarde para ser tratados. Otros pacientes que quedan fuera de VT, son aquellos que tienen una hora de inicio conocida pero que llegan tarde al hospital. Sin embargo, existen evidencias crecientes que la velocidad a la que progresa la isquemia tras una oclusión arterial, varia notablemente entre individuos. Así, mientras que en unos pacientes el territorio arterial está infartado en 6 horas, en otro puede que el infarto no esté establecido hasta las 10 horas. Este concepto choca con el enfoque actual de tratamiento basado en el tiempo, que establece que un paciente se trate en función del tiempo desde el inicio siempre que no haya un gran área infartada. En enfoque basado en la viabilidad del tejido ignora la hora de inicio del ictus. Así para tratar o no a un paciente, se realiza una neuroimagen para confirmar que hay tejido viable, si es así, se realiza el TEV independientemente del tiempo transcurrido. Hay estudios randomizados en marcha para demostrar esta hipótesis, y se han publicado estudios concluyendo que la seguridad y el buen pronostico es similar en pacientes fuera y dentro de ventana. Sin embargo, la mayoría de dichos estudios fueron realizados con dispositivos de primera generación, y algunos reportan pacientes de circulación anterior y posterior. Los stentrievers(ST), dispositivos de nueva generación han demostrado mayores tasas de recanalización y buen pronostico, de hecho las guías actuales recomiendan el TEV con ST. El objetivo primario de esta tesis fue comparar la seguridad y pronóstico de pacientes con ictus de circulación anterior fuera de ventana, tratados mediante TEV con ST, con los pacientes dentro de ventana(WTW). De un total de 468 pacientes 292(63.4%) estaban fuera de ventana(OTW) y 176(37.6%) dentro de ventana. El grupo fuera de ventana, se dividió en dos subgrupos de acuerdo a la hora de inicio: desconocida (UKO) in 113 (24.1%)pacientes y conocida con presentación tardía (KO-LP) en 63(13.5%) pacientes. Estos subgrupos no se pudieron agrupar en el grupo OTW porque un análisis estadístico previo mostró que no eran comparables. Por tanto, los resultados de estos pacientes se presentan de modo separado y comparados con pacientes dentro de ventana. No se encontraron diferencias significativas en buen pronóstico a 3 meses, con 49% en WTW, 42.2%% en UKO y 37.3% en KO-LP. Respecto a la seguridad, tampoco se encontraron diferencias en hemorragia intracraneal sintomática (6.2%WTW, 2.7%UKO y 9.5%KO-LP). Estos hallazgos apoyan el enfoque de viabilidad tisular en vez del basado en tiempo, en pacientes con ictus de circulación anterior tratados con EVT y ST, y seleccionados por neuroimagen, hasta que estén disponibles los resultados de los estudios randomizados. De ser positivos, uno de cada 3 pacientes que normalmente no se tratan por estar fuera de la VT podría ser tratado según nuestro estudio.Endovascular therapy (EVT) for stroke due to large vessel occlusion has been recently approved, changing dramatically the outcome of these patients, who otherwise would have a dismal outcome. However, there are patients automatically excluded from EVT because they arrive beyond the therapeutic time window. Traditionally, the time window (TW) for EVT has been 8 hours but the recent guidelines shortened the window to 6 hours. The TW is defined as the time from symptom onset to the time of groin puncture. In patients in whom the stroke onset is unclear either because the stroke occurred while sleeping or because the patient is unable to tell the onset because is aphasic on unconscious, and no witness is available, the onset is considered the last time the patient was seen normal. These patients often fall outside the window (OTW), because are too late to be treated. Other patients that are too late to be treated are those who, despite having a clear time of onset, arrive OTW. However, there is growing evidence showing that the speed at which the ischemia evolves after an arterial occlusion, varies significantly among individuals. Thus, while in some patients the arterial territory is infarcted in 6 hours, in other, the infarct might not be established after 10 hours. This concept radically challenges the current time-based approach, which establishes whether a patient should be treated or not based on the time from onset provided there is not a large area of infarcted tissue. Interestingly, the tissue-based approach disregards the time from onset. Consequently, the criteria to decide whether to treat a patient or not, would be to image the brain to find out if there is viable tissue, if so, treatment should be carried forward irrespective of the time since stroke onset. There are ongoing trials to prove this hypothesis, and non-controlled studies have been published showing that patients treated OTW have comparable safety and favorable outcomes than those treated within the window. However, those studies were performed with first generation devices and some refer to anterior and posterior circulation strokes. Regarding new generation strategies, stentrievers (ST) have demonstrated higher rates of recanalization and better outcomes. Current guidelines recommend the use of ST. The primary aim of this work was to compare the outcomes and safety of patients OTW with stroke due to anterior circulation (AC) occlusion treated with EVT with ST and selected by neuroimaging with the safety and outcomes of patients WTW. From a total of 468 patients, 292(63.4%) were patients WTW and 176 (37.6%)OTW. The group OTW was divided in two subgroups according to onset: unknown time of onset (UKO) in 113 (24.1%) patients and known onset but late presenters (KO-LP) in 63 (13.5%) patients. These subgroups could not be merged because p statistical analysis showed that they were not comparable, thus, the results had to be presented separately and compared with the WTW group. Regarding outcome, there were no significant differences good outcome at 3 months, with rates of 49% in WTW, 42.2%% in UKO and 37.3% in KO-LP. Regarding safety, there were no significant differences in symptomatic intracranial hemorrhage across groups (6.2%WTW, 2.7%UKO y 9.5%KO-LP). These findings support the tissue- based approach in patients with stroke due to AC occlusion treated with EVT using ST, and selected by neuroimaging, until the results of the randomized trials arrive. According to our study, a positive result would have a great impact on at least, one out of three patients that arrive OTW and are currently left untreated.
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Kodukula, Surya Ravikiran. "An Adaptive Time Window Algorithm for Large Scale Network Emulation." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31160.
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With the continuing growth of the Internet and network protocols, there is a need for Protocol Development Environments. Simulation environments like ns and OPNET require protocol code to be rewritten in a discrete event model. Direct Code Execution Environments (DCEE) solve the Verification and Validation problems by supporting the execution of unmodified protocol code in a controlled environment. Open Network Emulator (ONE) is a system supporting Direct Code Execution in a parallel environment - allowing unmodified protocol code to run on top of a parallel simulation layer, capable of simulating complex network topologies. Traditional approaches to the problem of Parallel Discrete Event Simulation (PDES) broadly fall into two categories. Conservative approaches allow processing of events only after it has been asserted that the event handling would not result in a causality error. Optimistic approaches allow for causality errors and support means of restoring state â i.e., rollback. All standard approaches to the problem of PDES are either flawed by their assumption of existing event patterns in the system or cannot be applied to ONE due to their restricted analysis on simplified models like queues and Petri-nets.
The Adaptive Time Window algorithm is a bounded optimistic parallel simulation algorithm with the capability to change the degree of optimism with changes in the degree of causality in the network. The optimism at any instant is bounded by the amount of virtual time called the time window. The algorithm assumes efficient rollback capabilities supported by the â Weavesâ framework. The algorithm is reactive and responds to changes in the degree of causality in the system by adjusting the length of its time window. With sufficient history gathered the algorithm adjusts to the increasing causality in the system with a small time window (conservative approach) and increases to a higher value (optimistic approach) during idle periods.
The problem of splitting the entire simulation run into time windows of arbitrary length, whereby the total number of rollbacks in the system is minimal, is NP-complete. The Adaptive Time Window algorithm is compared against offline greedy approaches to the NP-complete problem called Oracle Computations. The total number of rollbacks in the system and the total execution time for the Adaptive Time Window algorithm were comparable to the ones for Oracle Computations.Master of Science
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Chee, Chong Hin. "Totally-self-checking balance checkers and window comparators." Thesis, University of Hull, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389293.
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Li, Chuhe. "A sliding window BIRCH algorithm with performance evaluations." Thesis, Mittuniversitetet, Avdelningen för informationssystem och -teknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-32397.
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An increasing number of applications covered various fields generate transactional data or other time-stamped data which all belongs to time series data. Time series data mining is a popular topic in the data mining field, it introduces some challenges to improve accuracy and efficiency of algorithms for time series data. Time series data are dynamical, large-scale and high complexity, which makes it difficult to discover patterns among time series data with common methods suitable for static data. One of hierarchical-based clustering methods called BIRCH was proposed and employed for addressing the problems of large datasets. It minimizes the costs of I/O and time. A CF tree is generated during its working process and clusters are generated after four phases of the whole BIRCH procedure. A drawback of BIRCH is that it is not very scalable. This thesis is devoted to improve accuracy and efficiency of BIRCH algorithm. A sliding window BIRCH algorithm is implemented on the basis of BIRCH algorithm. At the end of thesis, the accuracy and efficiency of sliding window BIRCH are evaluated. A performance comparison among SW BIRCH, BIRCH and K-means are also presented with Silhouette Coefficient index and Calinski-Harabaz Index. The preliminary results indicate that the SW BIRCH may achieve a better performance than BIRCH in some cases.
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Ali, Abukar. "Time window of TNF-a in innate immunity against staphylococcal infection." Thesis, Högskolan i Skövde, Institutionen för vård och natur, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-4897.
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Staphylococcus aureus (S. aureus) is responsible for many human diseases including septic arthritis and sepsis shock. Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine involved in inflammation and produced mainly by macrophages and monocytes. It is believed to be involved in pathogenesis of septic arthritis. Time window of TNF-a in innate immunity against staphylococcal infection was studied in this project. Two experiments were carried out: In the first experiment mice were infected with a low dose (8x106cfu/mouse) of S. aureus to induce septic arthritis whereas in the second experiment the mice were infected with a higher dose (8x107cfu/mouse) of S. aureus to induce sepsis shock. All mice were divided into three groups. The first group was treated with anti-TNF-α 20 minutes after infection. The second group was treated with the anti-TNF-α three days after infection. The third group served as control and was injected with PBS instead of anti-TNF-α. The mice were regularly weighed and signs of arthritis and mortality were recorded. Two weeks after inoculation bacteria viable counts in different organs was done, as well as histopathological assessment of joints and measurement of cytokines in blood. We have observed that mice treated with anti-TNF-α had less severe arthritis and also less mortality. However, they had more bacteria accumulated in the kidneys and lost more weight compared to the control group. The results were mostly seen in the group early treated with TNF-α, compared to the late treated group. We conclude that anti-TNF-α might be potentially used as a therapy against septic arthritis and sepsis shock. This should be combined with antibiotics to eliminate the bacteria while the anti-TNF-α reduces the severity of the inflammation and thus reduce the risk of permanent joint destruction and mortality. We can conclude that blocking TNF-α early on is essential in order to get the best results.
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Shipp, Abbie J. Edwards Jeffrey R. "The moving window of fit extending person-environment fit research with time /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,370.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Kenan- Flagler Business School (Organizational Behavior and Strategy)." Discipline: Business Administration; Department/School: Business School, Kenan-Flagler.
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El-Nashar, Ahmed. "Multi-Vehicle Dispatching and Routing with Time Window Constraints and Limited Dock Capacity." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5197.
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The Vehicle Routing Problem with Time Windows (VRPTW) is an important and computationally hard optimization problem frequently encountered in Scheduling and logistics. The Vehicle Routing Problem (VRP) can be described as the problem of designing the most efficient and economical routes from one depot to a set of customers using a limited number of vehicles. This research addresses the VRPTW under the following additional complicating features that are often encountered in practical problems: 1. Customers have strict time windows for receiving a vehicle, i.e., vehicles are not allowed to arrive at the customer's location earlier than the lower limit of the specified time window, which is relaxed in previous research work. 2. There is a limited number of loading/unloading docks for dispatching/receiving the vehicles at the depot The main goal of this research is to propose a framework for solving the VRPTW with the constraints stated above by generating near-optimal routes for the vehicles so as to minimize the total traveling distance. First, the proposed framework clusters customers into groups based on their proximity to each other. Second, a Probabilistic Route Generation (PRG) algorithm is applied to each cluster to find the best route for visiting customers by each vehicle; multiple routes per vehicle are generated and each route is associated with a set of feasible dispatching times from the depot. Third, an assignment problem formulation determines the best dispatching time and route for each vehicle that minimizes the total traveling distance. iii The proposed algorithm is tested on a set of benchmark problems that were originally developed by Marius M. Solomon and the results indicate that the algorithm works well with about 1.14% average deviation from the best-known solutions. The benchmark problems are then modified by adjusting some of the customer time window limits, and adding the staggered vehicle dispatching constraint. For demonstration purposes, the proposed clustering and PRG algorithms are then applied to the modified benchmark problems.Ph.D.
Doctorate
Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering
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Júnior, José Messias Magalhães. "Flight scheduling problem, with time window, applied to a fractional jet ownership company." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2875.
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The present research addresses the problem of optimizing the flight schedule with time window applied to a fractional ownership jet company. The use of time window is intended to represent the situation in which the client is flexible to adjustment de departure time. This relaxation of time by the customer requesting air transport service enables the company to minimize the operational costs of the aircraft. In addition to the time window, the mathematical model includes the option to shared flight, in which the customers agree to make stops before reaching their final destination. In this work, different scenarios were analyzed, varying the time window 0-45 minutes in problems involving 09 to 30 clients. For the analysis of these scenarios, a tool was developed in AIMMS environment, called IOS (Icoaraci Optimization System). This tool has proved to be extremely useful in the development of this work. It has a user-friendly interface and is integrated into MS-EXCEL, where customer data are loaded. The Cplex12.4 is the solver responsible to reach the optimal flight schedule. For problems involving more than 10 clients, an heuristic was developed to provide a good and feasible solution. The use of time window and shared flight resulted in a reduction of up to 51.36% in total cost.
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Mohammadi-Aragh, Mahnas Jean. "Characterizing Student Attention in Technology-Infused Classrooms Using Real-time Active Window Data." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50945.
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As computers become more prevalent (and required) in engineering classrooms, it becomes increasingly important to address the dichotomy in our current understanding of their impact on student attention and learning. While some researchers report increased student learning, others report computers as a distraction to learning. To address this conflict, the research community must gain a fundamental understanding of how students use their computers in-class and how student attention is connected to learning and pedagogical practice. By gaining such an understanding, instructors\' design of classroom interventions aimed at increasing positive computer usage will be better informed. The purpose of this quantitative research study is to answer the overarching question "How do students use computers in technology-infused classrooms?" through an investigation of student attention. Based on the premise that one\'s senses must be oriented towards a stimulus to receive the stimulus, it is hypothesized that attention in a technology-infused classroom can be measured by monitoring a students\' top-most, active window (the Active Window Method). This novel approach mitigates issues with prior data collection methods, and allows researchers the opportunity to capture real-time student computer usage. This research serves the dual purpose of validating the Active Window Method and investigating applications of the method. The Active Window Method is validated by comparing real-time active window data with in-class observations of attention in engineering courses with large enrollments. The bootstrap resampling technique is used to estimate mean error rate. Post-tests are used to establish convergent validity by relating learning to active window data. Polytomous logistic regression is used to examine the probability of post-test score (response) over the range of attention levels (factor). Subsequent to validation, two applications of the Active Window Method were pursued. First, student computer use is characterized in multiple large lecture sections. Second, in answering calls to link student computer usage to pedagogical practices, an investigation into the relationship between pedagogy and attention is conducted by aligning time stamps of the active window record with technology-infused pedagogical activities identified in video recordings of lectures. An intervention time series analysis is employed to quantify the change in average attention due to pedagogical activities. Results demonstrate strong construct validity when directly comparing active window and attention. Convergent validity was weak when relating active window to learning. Results from the two applications illustrate that instructors\' use of technology and their pedagogical practices impact student computer use. Specifically, collecting student-generated content and polling question activities encourage on-task behavior. However, activities that include a website link encourage off-task behavior.Ph. D.
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Zhao, Yanxing. "Parametric inference from window censored renewal process data." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164678679.
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Selverstone, Jane Elizabeth. "Pressure-temperature-time constraints of metamorphism and tectonism in the Tauern Window, Eastern Alps." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/59036.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1985.Microfiche copy available in Archives and Science.
Bibliography: leaves 266-279.
by Jane Elizabeth Selverstone.
Ph.D.
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Saisi, Donna Lynn. "The use of model-based window display interfaces in real time supervisory control systems." Thesis, Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/25203.
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Cournoyer, Daniel. "Risk time-window specification and its impact on the assessment of medication-related adverse events." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101713.
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Post-marketing studies using medical administrative databases are often conducted to assess medication-related adverse events (AE). The determination of the risk time-window, defined as the period of time during which a medication-related AE could occur, is a crucial and challenging step toward the correct assessment of these AEs. In general, the unknown risk time-window consists of the number of days supplied, TS, for the medication and of a time-window. TW, that starts after TS and during which the medication could still produce AEs. Arguments have been made in favor of both short and long TW, durations. The aim of this thesis is to determine the impact of varying TW values on the assessment of the rate of cardiovascular AEs, using simulated data, and in a real-life example using administrative databases from Quebec. Results indicated that longer TW values tended to bias results toward the null.
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Zhang, Shu. "Stochastic orienteering on a network of queues with time windows." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1944.
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Motivated by the management of sales representatives who visit customers to develop customer relationships, we present a stochastic orienteering problem on a network of queues, in which a hard time window is associated with each customer and the representative may experience uncertain wait time resulting from a queueing process at the customer.
In general, given a list of potential customers and a time horizon consisting of several periods, the sales representative needs to decide which customers to visit in each period and how to visit customers within the period, with an objective to maximize the total reward collected by the end of the horizon. We start our study with a daily orienteering problem, which is a subproblem of the general problem. We focus on developing a priori and dynamic routing strategies for the salesperson to implement during a day.
In the a priori routing case, the salesperson visits customers in a pre-planned order, and we seek to construct a static sequence of customers that maximizes the expected value collected. We consider two types of recourse actions. One is to skip a customer specified by an a priori route if the representative will arrive late in the customer's time window. The other type is to leave a customer immediately after arriving if observing a sufficiently long queue (balking) or to leave after waiting in queue for a period of time without meeting with the customer (reneging). We propose customer-specific decision rules to facilitate the execution of recourse actions and derive an analytical formula to compute the expected sales from the a priori route. We tailor a variable neighborhood search (VNS) heuristic to find a priori routes.
In the dynamic routing case, the salesperson decides which customer to visit and how long to wait at each customer based on realized events. To seek dynamic routing policies, we propose an approximate dynamic programming approach based on rollout algorithms. The method introduces a two-stage heuristic estimation that we refer to as compound rollout. In the first stage, the algorithm decides whether to stay at the current customer or go to another customer. If departing the current customer, it chooses the customer to whom to go in the second stage. We demonstrate the value of our modeling and solution approaches by comparing the dynamic policies to a priori solutions with recourse actions.
Finally, we address the multi-period orienteering problem. We consider that each customer's likelihood of adopting the representative's product stochastically evolves over time and is not fully observed by the representative. The representative can only estimate the adoption likelihood by meeting with the customer and the estimation may not be accurate. We model the problem as a partially observed Markov decision process with an objective to maximize the expected sales at the end of the horizon. We propose a heuristic that decomposes the problem into an assignment problem to schedule customers for a period and a routing problem to decide how to visit the scheduled customers within the period.
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Barham, P. A. J. "The effect of time-window constraints and fleet size on the cost of a distribution operation." Thesis, Cranfield University, 1991. http://hdl.handle.net/1826/3865.
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Adopting a Continuous Space Modelling-type scenario of
no detailed data being available at a customer-specific
level, and on the basis, therefore, of basic information on
delivery-area size, total number of locations to be visited
and average road-speeds etc., quantitative expressions are
derived for,
the relationship between the number of vehicles
operating from a central depot and the total
fleet mileage that is required to visit a set
of locations, and,
2. the effect of time-window constraints on the
total cost of a similar operation.
These expressions are derived using a simulation-based
methodology, involving the setting-up of a computer program
which both generates Travelling-Salesman tours and provides
information on these tours at a detailed, disaggregated
level. In the time-constrained context, it was necessary to
develop a heuristic route-building procedure for solving
Travelling-Salesman Problems due to the algorithmic
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Mayer, Eckart [Verfasser]. "Globally Optimal Schedules for Cyclic Systems with Non-Blocking Specification and Time Window Constraints / Eckart Mayer." Aachen : Shaker, 2007. http://d-nb.info/1164338528/34.
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Ribeiro, Eric Arantes. "Modelo matemático e meta-heurística simulated annealing para elaboração de roteiros turísticos com base no tourist trip design problem." reponame:Repositório Institucional da UFES, 2015. http://repositorio.ufes.br/handle/10/1561.
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Made available in DSpace on 2015-11-03T19:59:38Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Modelo matematico e meta heuristica simulated annealing para elaboração de roteiros turísticos com base no tourist trip design problem.pdf: 2271247 bytes, checksum: faaad9e85f6978197ce7c7b03933a2ca (MD5) Previous issue date: 2015
O turismo é um importante setor para economia mundial e vem crescendo consistentemente nos últimos anos. Porém, um fator determinante para escolha do destino de um turista é a existência de pontos de interesse que ele deseja visitar na região e, para tanto, as informações dos pontos de interesse de uma região devem estar disponíveis. Dada às limitações de tempo do turista, não é possível para ele visitar todos os atrativos e, por essa razão, se faz necessário a criação de roteiros turísticos. Muito embora existam diversos pacotes de viagens com destinos predefinidos, contemplando locais mais populares, nos últimos anos tem crescido a procura por soluções que criem roteiros personalizados voltados às necessidades de cada turista. Para suprir essa nova demanda, Van Oudheusden e Vansteenwegen (2007) propuseram o Tourist Trip Design Problem (TTDP) e sugeriram o uso do Orienteering Problem (OP) e suas extensões para resolução do TTDP. Esta dissertação tem por objetivo o desenvolvimento de um modelo matemático e de uma meta-heurística Simulated Annealing (SA) para resolução do TTDP. O objetivo considerado consiste em gerar roteiros que maximizem a soma das notas atribuídas aos atrativos em função do grau de interesse do turista, levando em conta o período que ele tem disponível na localidade e o horário que cada atrativo está disponível para ser visitado.
Tourism is an important sector for the world economy and has been growing steadily over recent years. However, a decisive factor for the choice of a tourist destination is the existence of points of interest in the region he wants to visit and, therefore, the information from points of interest in a region should be available. Given the tourist time constraints, it is not possible for him to visit all the attractions and, therefore, it is necessary the creation of tourist routes. Although there are several packages with predefined destinations contemplating most popular locations in recent years has increased the demand for solutions that create custom tours for the needs of each tourist. To meet this new demand Van Oudheusden and Vansteenwegen (2007) proposed the Tourist Trip Design Problem (TTDP) and they suggested that the use of the Orienteering Problem (OP) and its extensions is the best approach to the TTDP. This thesis proposes the development of a mathematical model and a Simulated Annealing (SA) metaheuristic to solve the TTDP. The objective considered is to generate routes that maximize the sum of scores awarded to the attractions based on the degree of interest of the tourist taking into account the time that he has in the locality and the time that each attraction is available to be visited.
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Meskelevicius, Dziugas [Verfasser], Michael [Gutachter] Sabel, and Jörg [Gutachter] Felsberg. "Estimation of optimal time window for cortical mapping in awake craniotomy, based on intraoperative reaction time / Dziugas Meskelevicius ; Gutachter: Michael Sabel, Jörg Felsberg." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2019. http://d-nb.info/1199607282/34.
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Du, Nan, Mahdi Kiani, Christian G. Mayr, Tiangui You, Danilo Bürger, Ilona Skorupa, Oliver G. Schmidt, and Heidemarie Schmidt. "Single pairing spike-timing dependent plasticity in BiFeO3 memristors with a time window of 25ms to 125µs." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-171458.
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Memristive devices are popular among neuromorphic engineers for their ability to emulate forms of spike-driven synaptic plasticity by applying specific voltage and current waveforms at their two terminals. In this paper, we investigate spike-timing dependent plasticity (STDP) with a single pairing of one presynaptic voltage spike and one postsynaptic voltage spike in a BiFeO3 memristive device. In most memristive materials the learning window is primarily a function of the material characteristics and not of the applied waveform. In contrast, we show that the analog resistive switching of the developed artificial synapses allows to adjust the learning time constant of the STDP function from 25ms to 125μs via the duration of applied voltage spikes. Also, as the induced weight change may degrade, we investigate the remanence of the resistance change for several hours after analog resistive switching, thus emulating the processes expected in biological synapses. As the power consumption is a major constraint in neuromorphic circuits, we show methods to reduce the consumed energy per setting pulse to only 4.5 pJ in the developed artificial synapses.
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Gholikhamseh, Alireza Bizhan. "User interface software and emulation of microscope for a real-time telepathology system using an x-window environment." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278302.
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Many separate applications are being developed, tested, and used in the field of medical imaging. A Telepathology System (TPS) is one such application, allowing pathologist access to microscopy and patient files at remote workstations, through a communications network coupled with a pathologist viewing workstation. This thesis outlines the development of a user interface pathology workstation. It models microscope emulation in place of actual remote site microscopy by utilizing previously recorded specimen slide images. In addition, it models a communication network, and a remote site WS. User scenarios and performance characteristics for all three subsystems are outlined. The thesis confirms TPS can benefit telepathology by providing two way communications between remote sites, access to patient demographic files and prior specimen images for comperative study, and the benefit of long distance consultation. Finally, a discussion of an actual implementation is presented.
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Mann, Kimberly Lynn. "The First Thing Out the Window: Race, Radical Feminism, and Marge Piercy's "Woman on the Edge of Time"." W&M ScholarWorks, 2009. https://scholarworks.wm.edu/etd/1539626579.
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Hsiao, Li-Jen, and 蕭立人. "Time Analysis in a Time Window Network." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/69295384624239847177.
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博士國立中央大學
資訊管理研究所
92
Time window has been a common form of time constraint extensively considered in the literature. Basically, a time window is a time period, defined by the earliest and latest times, when a node is ready for traveling through. Although many variants of transportation problem in time-window networks have been proposed, none of them considers the possibility that time windows may be associated with the moving travelers or vehicles who travel only in these time periods. In this dissertation, a new variant of time-window constraint, we call it body clock constraint, is proposed at first. We assume that each vehicle has its own body clock and a capacity limitation on carrying goods, and we are trying to determine a minimal time schedule for sending a certain amount of goods from source to destination in a time-window network. The problem is studied by two cases, the first case considers single vehicle scheduling while the second one discusses multiple vehicles. Two different algorithms are presented to find the optimum schedule for each of the two cases. Secondly, to plan and select a path under a constraint on the latest entering time at the destination node, we propose a systematic method to generate time information of the paths and nodes on a time-window network. Algorithms are proposed to generate various time characteristics of the nodes, including the earliest and latest times of arriving at, entering, and departing from each node on the network. Using the basic time characteristics, we identify inaccessible nodes that cannot be included in a feasible path. Concurrently, we evaluate the flexibilities of accessible nodes in the waiting time and staying time. We also propose a method to measure adverse effects when including an arc. Based on the time characteristics and the proposed analysis schemes, we develop an algorithm for finding the most flexible path in a time-window network. We then extend the time window network to include body clock with traveler. Time characteristics of nodes and arcs are generated similarly. The flexibility and inaccessibility analyses of nodes and arcs are also discussed. Similarly, we provide an algorithm to find the most flexible path in this time-window network with traveler’s body clock.
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Bayram, Metin. "Multiple window time-frequency analysis." Thesis, 1996. http://hdl.handle.net/1911/14057.
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The bias-variance trade-off is an important issue is spectrum estimation. In 1982, Thomson introduced a powerful multiple window method for stationary signals that deals with the bias-variance trade-off in an optimal fashion. In this thesis, we extend Thomson's method to the time-frequency and time-scale planes, and propose a new method to estimate the time-varying spectrum of non-stationary random processes. Unlike previous extensions of Thomson's method, we identify and utilize optimally concentrated window and wavelet functions, and develop a statistical test for detecting chirping line components. The optimal windows are the Hermite functions for time-frequency analysis, and the Morse wavelets for time-scale analysis.
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Lee, Wei-Hung, and 李韋宏. "Parallel-Machine Scheduling with Time Window." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/99542058259082280045.
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碩士中原大學
工業與系統工程研究所
105
Through the improvement of science and technology industry, the demand of IC increases and effects the whole semi-conductor process lane. The design of IC has become more and more diversification and the packing technic has also improved since the great compete between IC testing and packing company, decrease the due date and increase process rate is an important task. This research investigate on order scheduling and parallel machine assignment problem in single factory, in semiconductor wafer packing process, the out decide the usage of the bottleneck wiring and what effects the usage is the frequency of changing machine progress, once the frequency more often, the less its able to process and effect the output. This research focuses on wiring as target to find the best input order in order to decrease the frequency to the maximum machine usage. What we consider : scheduling and parallel-machine assignment is a NP-hard problem, first we propose mathematical model of mixed integer programming using auto transform order information into what is needed and use genetic algorithm in Matlab to solve, once we get similar optimal solution, the optimal program will automatically calculate the daily usage from wafer milling to wiring. This makes the consultation of the order of arranging.
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Shen, Sheng-Yuan, and 申生元. "Time Window Constrained Vehicle Routing Problems." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/09780822489787552720.
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博士國立交通大學
工業工程與管理系
87
This research involves developing heuristic solution methods for three types of time window constrained vehicle routing problems. They are the Vehicle Routing Problem with Time Windows (VRPTW), the Vehicle Routing Problem with Time Windows and Backhauls (VRPTWB), and the Vehicle Routing Problem with Time Windows and Multiple Vehicle Types (VRPTWMVT). The time windows considered in this study constitute hard constraints. Extensively computational results are reported. Benchmark problems for VRPTW and VRPTWB are taken from the literature. A total of 168 sample problems for VRPTWMVT have been newly created to evaluate the performance of our heuristics. Furthermore, we also compare our results for VRP, VRPB, and VRPMVT with the best-known solutions found in the literature. In overall, computational studies show that our heuristics in terms of both solution quality and computation time are superior to or at least competitive with all other heuristics published. The primary contributions of this dissertation are summarized as follows. (1) A new neighborhood structure is introduced in dealing with VRPs. Instead of the traditional way in constructing neighborhoods using a node(s)-to-node(s) relationship, we generate a set of route-neighborhoods by focusing on a node(s)-to route(s) relationship. Through the adjustment of the size of route-neighborhoods, one might obtain near optimal solutions due to a thorough exploitation of solution space. (2) An operational framework for minimizing the number of vehicles used is proposed. A key component in the framework is the introduction of an end-effect-handling procedure. When only a small number of customers is left with no feasible positions with respect to the existing set of routes, a specially designed procedure is applied on them such that feasible positions can possibly be found among the current routes instead of immediately constructing a new route for them. Information extracted from previous construction history is used in defining the end-effect-threshold for justifying what is a small number of customers. In addition, we present a scheme for constructing routes in a nested parallel manner. (3) Several insertion-based savings heuristics that generalize the traditional combining-based savings approach are first addressed to solve the VRPTWMVT. The introduction of a parameter referring to the degree of sequential route construction has substantially improved the solution quality.
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Hsu, Tung-Yeh, and 徐東業. "On multi-objective job shop scheduling problem with time window – Dynamic time window selection ant colony optimization." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/51566062731613459510.
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碩士輔仁大學
管理學研究所
97
Job shop scheduling problem (JSP) is the most complex situation among all, and JSP is also the most common situation in practical situation. Generally, JSP can be solved by integer programming (IP) for optimal solution, but the time consumed rises rapidly as the problem size grows. Therefore, heuristic methods are applied to greatly reduce the time consumed. Among all heuristic methods, ant colony optimization(ACO) is the most widely used in recent years; however, in facing problems with time window constrains, ACO is not yet endowed with a effective algorithm. Thus, based upon ACO, this paper presents new algorithm to solve JSP with TW, and the approach is named “dynamic time window selection ant colony optimization(DWSACO)”. This paper studies on JSP with TW, and there is a given ready time for every job; the purpose is to minimize weighted average of the sum of total earliness and total tardiness. Then the problem is solved by IP, ACO, and DWSACO respectively, and at the end the effectiveness and robustness of each method are analyzed, expecting to contribute both practically and academically. The result shows that both ACO and DWSACO are able to obtain approximate optimal solution in a short time, and although in different sizes of problem, DWSACO consumes a bit more time than ACO does, the solutions obtained by DWSACO are closer to optimal solution than ACO’s. Near the end of this paper, the improve rates of effectiveness and robustness show that DWSACO is superior to ACO.
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Lin, Chien-Yu, and 林建佑. "Improvement Vehicle Routing Problem with Time Window." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/78904662441903156753.
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碩士東吳大學
資訊管理學系
99
Vehicle routing problem with time window has been the focus of many researchers recently and also proved to be NP-hard. In this thesis, a variety of heuristics are introduced and Solomon problems are used as basis for research. Through the detailed analysis of the customers’ geographical and time windows information, computations are made to generate dynamic parameters. Moreover, this research imported these parameters into a sequential tour-building algorithm for solutions. The results are further transformed to map the problem data. Finally, through the graphical display and chart analysis, the visualized solutions are presented to the users.
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Lin, Yen-Po, and 林彥伯. "Launch Time Window Determination for Missile Interceptor." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/62899332894810223587.
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碩士國立交通大學
電控工程研究所
99
When an attacking missile is detected, the missile defense system must decide when to launch the missile interceptor. The choice of a proper launch time is important because given the physical constraints on the interceptor, a poor choice of launch time alone may cause the interception to fail. This thesis discusses the determination of launch time window for a missile interceptor, which is formulated as constrained optimization problems. The earliest and the latest allowable launch times are determined by numerically solve the corresponding minimization and maximization problems. Three incoming threats are considered. Numerical results show good agreement with results obtained via six degree of freedom simulations employing midcourse guidance.
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Liu, Chien-Hung, and 劉建宏. "Truck and Trailer Routing Problem with Time Window." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/18239047623478269935.
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碩士國立中央大學
土木工程研究所
93
The Truck and Trailer Routing Problem (TTRP) is a variant of the Vehicle Routing Problem (VRP). The problem extends the basic VRP to take a real-life application into account. In the TTRP, customers can be serviced by a truck alone or a vehicle (a truck pulling a trailer), therefore there are three types of routes in a solution to the TTRP: a pure truck route, a pure vehicle route, and a complete vehicle route which includes the vehicle route and the sub-tours serviced by a truck alone. This research extends TTRP to consider time window constraint, and defines the Truck and Trailer Routing Problem with Time Window (TTRPTW). This research also applies a heuristic to solve the TTRPTW and test on 17 problems which were designed based on Solomon’s standard VRPTW problems.
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Hsiao, Ho-Yuan, and 蕭賀元. "The Traveling Salesman Problem with Time Window Constraints." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/10971137226081629414.
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碩士東海大學
資訊管理學系
99
The traveling salesman problem with time window constraints is an extension research of the traveling salesman problem. It also joined the process control issues and the customer-oriented concept. To provide the service within a specific service time window that suits the needs of customers. Because of considering the time window constraints, the traveling salesman problem would be more practical in the daily life. There are two research topics in this study. The first one is the traveling salesman problem that considers sleep within hard time window constraints. The other one is the traveling salesman problem that considers time-dependent paths within soft time window constraints. We use the simulated annealing and the genetic algorithm respectively to solve the two research issues. For each research issue, the approaches will be illustrated by an example. After all, the solution quality and effectiveness of our approaches in the study will be proved by examples and random experiments sequentially. Therefore, our approaches would be a reference for a right decision-making related to the traveling salesman problem with time window constraints.
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Shing-Chen, Wen, and 陳文興. "On job shop scheduling with time window problem." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/67466988537657545685.
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碩士輔仁大學
管理學研究所
93
Scheduling is a very important field in production management. And job shop is a most complex production system on the field. Scheduling operations expect to bring into full play the minimum stock level, wastes, the least idle time and deliver the goods on time, so derive the time window problem. Previous literature regarding job shop scheduling problem (JSP) rarely concerns the machine set-up time, and measure regular is minimizing the tardiness. Here the due date is discussed one point. The study will confer the JSP, and let the due date for an interval. Focusing on scheduling with time window of JSP and expect to get the solution close to the time window. Minimize the total penalty due to the earliness and tardiness. The property of our study is NP-hard. So we construct the mathematics model for JSP with time window first, and then test the simulate data. The solution got by ant colony optimum (ACO) programs that written by C-language and compare with the best solution gotten by LINGO 7.0 to test the efficiency and robust. The result was pointed out the ACO has good efficiency on the test. And the solving time is less than LINGO. So ACO had both effectiveness and efficiency that stressed on business management.
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lee, jenhon, and 李健弘. "Linear fractional shortest path problem with time window." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/45079685657297779081.
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Liao, Kuo-Chun, and 廖國均. "The Recommendation of Visiting Route under the Time Window." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/nnzknu.
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碩士國立臺北科技大學
工業工程與管理系碩士班
100
Nowadays, people have concerned their life qualities more than before. And the trend of visiting exhibitions when on weekends has come to a big growth. Therefore, it very crowed on weekends in Taiwan because people would like to go outside, this reason, people stuck in traffic jams very easily. People would waste too much time on waiting or out of control of schedule interrupt their good mood. Furthermore, most of travel spots are getting together in a particular area, so it’s also important. Tourists are required to buy tickets to get into spots. Hence, the contribution of this paper is to enable people to make good use of their visiting or playing routine in a limited time. This paper uses MOTSP model to develop Modified-NSGA-II multi-objective algorithm, path system with RFID system imports in-time system concept, to control well of tourists who it are playing or waiting. Also divides time zone to calculate and update the number of tourist and the density each spot. The goal are making tourist play all the facilities with time and by improving shortcuts of the spot, them attracting more tourists to come.
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Chen, Chi-Shen, and 陳契伸. "Vehicle Routing Problem with Hard/Soft Time Window Constraints." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/26746509312112443878.
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碩士中原大學
工業工程研究所
89
This research proposes a heuristic, Tabu-Threshold Algorithm (TTA), to efficiently and effectively solve Vehicle Routing Problem with Hard/Soft Time Window Constraints (VRPHTW / VRPSTW). TTA integrates Tabu Search (TS) and Threshold Accepting (TA), two of the most popular generic heuristics in solving VRPHTW in recent years. The first objective is to determine the route that minimizes the total vehicle travel distances. This, in turn, leads to quick response to customer demands. The second objective is to find the minimum required number of vehicles. This, in turn, results in low transportation cost. Solomon’s 56 benchmark instances were tested for TTA. TTA consists of three phases: initial solution construction, local search improvement, and generic search improvement. In the initial solution construction phase, Enhanced Savings Method and Nearest Neighbor Method are used. In the local search improvement phase, vehicles reduction and neighborhood search modules are proposed. In the generic search improvement phase, a hybrid algorithm of TS and TA is used to improve the initial solution. TTA is coded in Visual Basic 6.0 and evaluated at a PentiumⅢ550 PC. TTA results in good solution quality and efficiency. The average deviation of distance is less than 5% and the average deviation of vehicle numbers is about 8%, compared to the known “best” solutions. The average computation time is approximately 5 minutes to solve all the instances.
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Jen-Hao, Huang. "The Probabilistic Traveling Salesman Problem with Real-time Requests and Time Window Constraints." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0016-0109200613413707.
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Huang, Jen-Hao, and 黃仁豪. "The Probabilistic Traveling Salesman Problem with Real-time Requests and Time Window Constraints." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/00462895620319658923.
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碩士國立清華大學
工業工程與工程管理學系
94
Nowadays, in order to keeping competitive advantages, overnight carriers are searching for more stable orders. On the other hand, carriers also concentrate on developing abilities to deal with real-time demands continuously. The common goal of overnight carriers is satisfying needs of customers as possible while keeping operating costs competitive. The purpose of this thesis is to construct a Probabilistic Traveling Salesman Problem model with Time Window constraints (PTSPTW) to cope with probabilistic demands. Meanwhile, the idea of Double Horizon is incorporated into the model to maintain the flexibility of the a priori route for future possible immediate requests. A two stage heuristic algorithm is proposed to solve the PTSPTW. The conclusion is that the flexibility of the a priori route is helpful not only to satisfy more demands but also to reduce total traveling time of the vehicle in the problem with real-time demands, especially the cases which the weight of real-time demands is high. Besides, in the problems with narrow time window or high request probabilities, the a priori route with more flexibility has more advantages.
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Ho, Meng-Chieh, and 何孟潔. "Time Dependent Vehicle Routing Problems with Time Window and Split Delivery in City Logistics." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/r76mq7.
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碩士國立東華大學
運籌管理研究所
100
Traditional wholesalers have to deal with many different kinds of retailers every day. Wholesalers, in order to improve service quality, usually provide distribution services. There are, however, many different kinds of retailers, each of with different business hours, and wholesalers must deliver goods in different time windows. This presents a typical VRPTW problem. On the other hand, vehicles deliver goods at different times, meaning traffic flow will be different, and this affects delivery times. In order to meet the actual demand, we add the time dependent constraint distribution time with the traffic flow change in the distribution process. In the traditional VRP, each customer can be served by exactly one vehicle. In order to make the service efficient, we relax this constraint, so that each customer can be served by more than one vehicle. We construct mathematical models that provide optimal solutions for the above situations. We use the optimization software CPLEX to solve small case problems. And we use a basic genetic algorithm to solve the large problem with Matlab. Finally, we use the example of Solomon Instances to explore the difference between distribution by split delivery and without split delivery, and use practical examples of tests.
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Wei, Zong-Che, and 魏宗徹. "The Vehicle Routing Problem With Backhaul and Time Window Constraints." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/35707804237946650508.
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碩士元智大學
工業工程研究所
89
The transportation cost accounts for a large amount in logistics system, hence how to design a useful vehicle routing rule can reduce the transportation cost and increase the profit is the primary issues for the company. Ordinary Vehicle Routing Problem with Backhaul（VRPB）assumes that the pickup operations are followed by delivery. The operations are either simple delivery or pickup, and single vehicle type is assumed. The purpose of this study was to allow the priority flexibility of pickup and delivery via pickup allowance rate. Where the delivery goods was over the specified percents of carrying capacity, this vehicle could break the priority of delivery and then made both delivery and pickup operation at the customer station. However, both delivery and pickup operation could not exceed the vehicle capacity constraint. Customers were classified by 3 subgroups, one for delivery（or linehaul）, one for pickup（or backhaul）and the other is the mix of linehaul and backhaul. We also study the imparts of both single type and mixed type vehicle on the solution. A genetic algorithm was applied to the problem and parameters were determined by Taguchi Method for optimal design. The test problem by Solomon were tested to check the feasibility of the approach. The results show that the minimize total cost occurred at the level of pickup customers is 50% and percent of pickup allowance is 10%. The mix vehicle consideration performs better is total cost（-19.5%）and average utilization（+14.4%）.
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Chun, Bock Jin, and Sang Heon Lee. "Algorithms and heuristics for time-window-constrained traveling salesman problems." Thesis, 1985. http://hdl.handle.net/10945/21133.
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Wan-YuHsieh and 謝宛彧. "Truck Dock Assignment Problem of Distribution Center with Time Window." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6398qv.
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碩士國立成功大學
交通管理科學系
107
With the rise of e-commerce and logistics industry, the distribution center has received more and more attention recently. Cross-docking is an effective management strategy to solve the problem of logistics. It can make the delivery more efficient and reduce the cost. In this research, we focus on the dock assignment problem in distribution center and we consider the number of trucks exceeds the number of docks. We emphasize assigning both inbound and outbound trucks to multiple docks and the sequence of trucks. Every truck has their hard time window constraint of the arrival time at the dock. The objective is to minimize the waiting time between actual and expected arrival time when the truck arrives at the dock. The dock assignment problem will be affected by four factors: the tightness of the time windows, the ratio of the number of the trucks and the number of dock doors, the size of the case, and the simultaneousness of the truck arrivals. To solve the dock assignment problem, we provide two methods in our research. The first method is to formulate a mixed integer programming model and use optimization solver, Gurobi, to solve the small-scale problems. Because dock assignment and truck scheduling problems are NP-hard, its integration is more difficult to solve. Therefore, we provide the second method: Tabu Search. The result shows that Tabu Search is able to find good solution in much more competitive computation time, comparing to Gurobi. We also provide an effective mathematical model of the dock assignment problem with hard time window.
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Chen, Bo-Xian, and 陳柏憲. "A Fast Algorithm for Dynamic Time Warping with Adaptive Window." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/subw25.
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碩士國立中山大學
資訊工程學系研究所
106
The classification problem is a critical issue in data processing field, especially emph{time series classification} (TSC) problem. In the TSC problem, the calculation of the distance of two time series is the kernel issue. One of the famous methods for the distance calculation is the emph{dynamic time warping} (DTW), based on the dynamic programming. However, the time complexity of DTW is $O(n^2)$. When the data size is large, it takes too much time to calculate. In order to overcome time consuming problem, emph{dynamic time warping with window} (DTWW) combines the warping window into DTW calculation. This method reduces the computation time by restricting the number of possible solutions, so the answer of DTWW may not be the optimal solution. In this thesis, we present a method that expands the possible solutions in the minimum first order. Our method not only reduces the required computation time, but also gets the optimal answer.
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Juan, Chi-Hsien, and 阮其賢. "An Improved Feasible Space Window Method for Time Series Segmentation." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/89404369587331182580.
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碩士國立中興大學
資訊科學與工程學系
103
Time series segmentation is one of the current research topics on data mining. As recent studies often apply time series segmentation in stocks analysis and big data processing, identifying the characteristics or turning points on the time series can effectively facilitate the analysis and forecast with the data set. Among a number of approaches to time series segmentation, PLR (Piecewise Linear Representation) has been regarded as the most classic one. It shows high accuracy, yet it takes considerable amount of time to conduct the algorithm, especially for big data segmentation. In view of such issue, this research proposes a solution which can not only improve the analysis efficiency with PLR, but also ensure that the result is within the error bound generated by PLR. In this thesis, we propose a time series segmentation method called Piecewise Linear Representation based on Feasible Space (PLRFS). In this method, we find segmentation points based on feasible space as the time series data streaming in. The proposed method has two features. One is that it facilitates processing time with errors within an acceptable range, and the second is that the segmentation can be conducted as soon as a feasible space is located without collection of complete data. According to the experimental results, the proposed method only takes 1/12 of the processing time required by the original PLR algorithm. Moreover, the trend of original data can still be observed with the set of segment points generated by the proposed method.
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LIN, FENG-LONG, and 林豐隆. "A design of refined window protocol for time-constrained communication." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/33164021423012437876.
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Chen, Yi-Huei, and 陳怡卉. "Midterm Berth Planning Problem Considering Ship Selection and Time Window." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/76322177166446778142.
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碩士國立交通大學
運輸與物流管理學系
102
Under the context of a congested container terminal, solving the congested problem has become the most important issue to port operators. The study developed two mixed integer programming (MIP) models for the tactical berth template design problem. With the objective of cost minimization, the terminal operator determines the berth assignment and the service starting time of the potential calling ships on a cyclical basis with respect to a fixed length of planning horizon. The operator has the flexibility of denying a ship at the price of losing a ship-dependent revenue or berthing it within a specific time window. In particular, an early or late penalty cost is incurred, if the ship service starting time is deviated from the preferred target time. This study compared the performances of the two IP formulations, one directly using the binary variable to represent the decision of berth assignment and service sequencing and the other indirectly making use of the generalized set-partitioning model. It was found that the performance of the latter is much better. This study further designed a heuristic solution algorithm based on the classic maximum weighted matching problem with respect to the generalized set-partitioning formulation. Based on the numerical experiments, the model and the solution algorithm developed in this study are promising in enhancing the literature of the tactical planning of container terminals
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Oberholzer, Christiaan Vermaak. "Time-window optimization for a constellation of earth observation satellite." Thesis, 2009. http://hdl.handle.net/10500/2706.
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Thesis (M.Com.(quantitative Management))Satellite Scheduling Problems (SSP) are NP-hard and constraint programming and metaheuristics solution methods yield mixed results. This study investigates a new version of the SSP, the Satellite Constellation Time-Window Optimization Problem (SCoTWOP), involving commercial satellite constellations that provide frequent earth coverage. The SCoTWOP is related to the dual of the Vehicle Routing Problem with Multiple Timewindows, suggesting binary solution vectors representing an activation of time-windows. This representation fitted well with the MatLab® Genetic Algorithm and Direct Search Toolbox subsequently used to experiment with genetic algorithms, tabu search, and simulated annealing as SCoTWOP solution methods. The genetic algorithm was most successful and in some instances activated all 250 imaging time-windows, a number that is typical for a constellation of six satellites.
Quantitative Management
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Huang, Hsin-Hsiang, and 黃信翔. "Solving a Pickup and Delivery Problem with Time Window Constraints." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/16996763664468639002.
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碩士國立交通大學
運輸科技與管理學系
94
This research focuses on the modeling and solution technique of Pickup and Delivery Problem with Time Windows Problems (PDPTW). We first formulate PDPTW as a set partitioning model. This model takes customer requests, service precedence, time windows, vehicle capacity, and working time into account. The objective is to find a set of feasible routes with minimum cost. A column generation based heuristic method is developed to solve this model. A shortest path problem with multiple side constraints is formulated as the sub-problem in order to find columns which could improve the objective function of the master problem. We also propose a modified Dijkstra’s algorithm to solve this shortest path problem. Numerical experiments indicate that the proposed solution method is sound and promising. The testing results also demonstrate that this method is good for large scale problems.
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蔡佳君. "The Variable-Capacity Vehicle Routing Problem With Time Window Constraints." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/45262786077175990175.
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