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Optimized Crossover Genetic Algorithm for Vehicle Routing Problem with Time Windows

Optimized Crossover Genetic Algorithm for Vehicle Routing Problem with Time Windows

This study presents a genetic algorithm that uses an optimized crossover operator to solve the vehicle routing problem with time windows. The proposed algorithm has been tested against the best known solutions reported in the literature, using 56 Solomon's problems with 100 customers. The computational results showed that the proposed algorithm is competitive in terms of the quality of the solutions found (in terms of total travel distance). As for future work, it may be interesting to test OCGA with additional benchmarks of VRPTW.

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Route Elimination Heuristic for Vehicle Routing Problem with Time Windows

Route Elimination Heuristic for Vehicle Routing Problem with Time Windows

Abstract: The paper deals with the design of a route elimination (RE) algorithm for the vehicle routing problem with time windows (VRPTW). The problem has two objectives, one of them is the minimal number of routes the other is the minimal cost. To cope with these objectives effectively two-phase solutions are often suggested in the relevant literature. In the first phase the main focus is the route elimination, in the second one it is the cost reduction. The algorithm described here is a part of a complete VRPWT study. The method was developed by studying the graph behaviour during the route elimination. For this purpose a model -called “Magic Bricks” was developed. The computation results on the Solomon problem set show that the developed algorithm is competitive with the best ones.
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A solution for a real-time stochastic capacitated vehicle routing problem with time windows

A solution for a real-time stochastic capacitated vehicle routing problem with time windows

Several approaches were made to solve the VRPTW problems. The use of meta-heuristics is a common solution [Mou08, TM08, BG02, LYL11, GTA99, GGLM03]. Other solutions in- clude heuristics like the one for the distribution of fresh vegetables presented in [OS08] in which the perishability represents a critical factor. The problem was formulated as a VRPTW with time-dependent travel-times, where the travel-times between two locations depend on both the distance and the time of the day. The problem was solved using a heuristic approach based on the Tabu Search and performance was verified using modified Solomon’s problems. A somewhat similar work was proposed in [TK02], which deals with distribution problem formulated as an open multi-depot vehicle routing problem encountered by a fresh meat distributor. To solve the problem, a stochastic search meta-heuristic algorithm, termed as the list-based threshold accepting algorithm, was proposed. In [AS07] a generalization of the asymmetric capacitated vehicle routing problem with split delivery was considered. The solution determines the dis- tribution plan of two types of products, namely: fresh/dry and frozen food. The problem was solved using a mixed-integer programming model, followed by a two-step heuristic procedure.
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en 0104 530X gp 0104 530X2359 15

en 0104 530X gp 0104 530X2359 15

Palavras-chave: Roteamento de veículos; Múltiplos entregadores; Busca Local Iterada; Busca em Vizinhança Grande. Abstract: This paper addresses the vehicle routing problem with time windows and multiple deliverymen, a variant of the vehicle routing problem which includes the decision of the crew size of each delivery vehicle, besides the usual scheduling and routing decisions. This problem arises in the distribution of goods in congested urban areas where, due to the relatively long service times, it may be dificult to serve all customers within regular working hours. Given this dificulty, an alternative consists in resorting to additional deliverymen to reduce the service times, which typically leads to extra costs in addition to travel and vehicle usage costs. The objective is to deine routes for serving clusters of customers, while minimizing the number of routes, the total number of assigned deliverymen, and the distance traveled. Two metaheuristic approaches based on Iterated Local Search and Large Neighborhood Search are proposed to solve this problem. The performance of the approaches is evaluated using sets of instances from the literature.
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A guide to vehicle routing heuristics

A guide to vehicle routing heuristics

Rochat and Taillard22 have developed an adaptive memory mechanism for the capacity and route duration constrained VRP and for the VRP with time windows, based on the earlier [r]

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Analysis of pick-up and delivery and dial-a-ride problems dynamization methods and benchmark instances

Analysis of pick-up and delivery and dial-a-ride problems dynamization methods and benchmark instances

As instâncias de benchmark disponíveis para as versões dinâmicas do problema de co- leta e entrega com janelas de tempo (PDPTW - Pickup and Delivery Problem with Time Windows) e do problema dial-a-ride (DARP - Dial-A-Ride Problem) não compar"lham as mesmas caracterís"cas e não necessariamente cobrem todas as caracterís"cas de situ- ações reais. Analisa-se conjuntos de instâncias de PDPTW e DARP dinâmicos (DPDPTW e DDARP) atualmente disponíveis para uso e os métodos usados para gerá-los a par"r de instâncias está"cas. Cada método de dinamização é aplicado a cada instância está"ca originalmente usada por eles. As instâncias dinâmicas resultantes são analisadas com as medidas de grau de dinamismo e urgência, bem como pelo número de pedidos está"cos e a correlação entre os limites inferiores das janelas de tempo de coleta e os instantes de chegada dos pedidos. Os resultados mostram que os conjuntos estudados apresen- tam baixa variabilidade de grau de dinamismo e urgência independentemente do mé- todo ou da instância está"ca usados para a dinamização.
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Scatter search para problemas de roteirização de veículos com frota heterogênea, janelas de tempo e entregas fracionadas.

Scatter search para problemas de roteirização de veículos com frota heterogênea, janelas de tempo e entregas fracionadas.

This work studies the implementation of heuristics and scatter search (SS) metaheuristic in a real heterogeneous fleet vehicle routing problem with time windows and split deliveries (HFVRPTWSD) in Brazil. In the vehicle routing problem with time windows and split deliveries (VRPSD) each client can be supplied by more than one vehicle. The problem is based in a single depot, the demand of each client can be greater than the vehicle’s capacity and beyond the time windows constraints, and there are also vehicle capacity and accessibility constraints (some customers cannot be served by some vehicles). The models were applied in one of the biggest retail market in Brazil that has 519 stores distributed in 12 Brazilian states. Results showed improvements over current solutions in a real case, reducing up to 8% the total cost of the operation.
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Using boreholes as windows into groundwater ecosystems.

Using boreholes as windows into groundwater ecosystems.

Groundwater ecosystems remain poorly understood yet may provide ecosystem services, make a unique contribution to biodiversity and contain useful bio-indicators of water quality. Little is known about ecosystem variability, the distribution of invertebrates within aquifers, or how representative boreholes are of aquifers. We addressed these issues using borehole imaging and single borehole dilution tests to identify three potential aquifer habitats (fractures, fissures or conduits) intercepted by two Chalk boreholes at different depths beneath the surface (34 to 98 m). These habitats were characterised by sampling the invertebrates, microbiology and hydrochemistry using a packer system to isolate them. Samples were taken with progressively increasing pumped volume to assess differences between borehole and aquifer communities. The study provides a new conceptual framework to infer the origin of water, invertebrates and microbes sampled from boreholes. It demonstrates that pumping 5 m 3 at 0.4–1.8 l/sec was sufficient to entrain invertebrates from five to tens of
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Generating Representative Sets and Summaries for Large Collection of Images Using Image Cropping Techniques and Result Comparison

Generating Representative Sets and Summaries for Large Collection of Images Using Image Cropping Techniques and Result Comparison

Using these two pre-cluster techniques, images are stored in RGB form and clustering algorithm (k-means) is applied. For gray scale technique, all the images are converted in gray scale and are stored in vectors and again the cluster algorithm is applied in second phase. From the result of clusters it is found that the pictures with same appearance with different pixel values do not go to the same cluster. It means taking a picture of any particular landscape with normal mode and taking the same picture with zoom, would not go in the same clusters although both have same visual features. Because of this big drawback it is not possible to stand on finding a representative set and summarization which holds the selection criteria. Therefore, experiments with this pre-cluster stage are stopped and focus is set only on the next two techniques.
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Senescence with more time and better

Senescence with more time and better

In medical practice, we have seen that the incidence of chronic diseases of the nervous system, particularly Alzheimer’s disease and Parkinson’s disease, inevitably increases with age. hus, we expected people over 95 years, often called “the oldest old” to be our weaker patients. We have personally detected, however, that “the oldest old” are often the healthier and agile elderly, in better shape than thought. his phenomenon can be explained by selective survival, related to the so-called longevity genes (protective against the development of diseases) and changes in daily activities, with the inclusion of exercises.
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Duality with time-changed Lévy processes

Duality with time-changed Lévy processes

The paper is organized as follows: in Section 2 we introduce time-changed L´evy processes. In Section 3 we describe the market model and introduce the pricing problem, illustrating with some important examples of traded derivatives. In Section 4 we describe the Dual Market Method, a method which allows to reduce the two stock problem into a one stock problem. In Section 5 we study the put–call duality relation. In Section 6 we have the conclusions and finally an appendix.

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Enigma McAfee Tudo sobre a internet  Vizente Besteirol Enigma McAfee

Enigma McAfee Tudo sobre a internet Vizente Besteirol Enigma McAfee

II) Usam poderosos recursos do sistema, deixando a máquina cada vez mais lenta - é, o Windows faz isso. III) Vão, aos poucos, destruindo seu winchester - tá, o Windows faz isso. IV) São[r]

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Temporal integration windows for naturalistic visual sequences.

Temporal integration windows for naturalistic visual sequences.

It is interesting to note that although the duration of individual shots in Hollywood films varies greatly, it is rare to find shots less than around 2 seconds [31] (see www.cinemetrics.lv). Movie trailers and action sequences tend to have relatively short shot durations (a larger number of cuts per minute) of around 2– 3 seconds (the average shot length in a Michael Bay film is 3.0 seconds: www.cinemetrics.lv), while tracking shots of several minutes can also be found, for example, in the work of director Alfonso Cuaro´n. Given that people typically move their eyes several times per second, even the shortest shots are usually an order of magnitude longer than human fixation durations while reading. Nonetheless, movie shots have often been compared to fixations by film theorists and directors [32]. This raises the question of why film is so ‘‘inefficient’’ compared to a human fixation and why there are not several cuts per second in typical movies. One possibility, consistent with the current results, is that event information is accumulated over a period of a few seconds, making clip durations of 2–3 seconds an ideal compromise between efficiency (showing as many different shots as possible in a short period of time) and ease of viewing.
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Apostila   Manual completo   Windows Script Host

Apostila Manual completo Windows Script Host

Um arquivo do WSC nada mais é que um arquivo texto com extensão .wsc que utiliza a XML juntamente com uma linguagem de script compatível com a tecnologia ActiveX (como o VBScript e o JScript) para criar um componente de script reutilizável. Para desenvolver um componente de script, basta um editor de texto simples como o Notepad. No entanto, no site http://msdn.microsoft.com/scripting é possível obter gratuitamente um wizard que auxilia no desenvolvimento de componentes de script do WSC. Para ser utilizado, um componente de script WSC necessita: • do arquivo scrobj.dll (run-time do WSC) instalado; • de quaisquer arquivos (executáveis, bibliotecas, etc.)
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Absence of Doppler signal in transcranial color-coded ultrasonography may be confirmatory for brain death: A case report

Absence of Doppler signal in transcranial color-coded ultrasonography may be confirmatory for brain death: A case report

Experience with TCCS, albeit substantially lower than those with TCD, shows comparable sensitivity and specificity rates in terms of brain death confirmation (21,22). The availability of acoustic window within the temporal bone does not significantly differ between TCD and TCCS (20). However the detection of window quality is easier and more rapid with TCCS through depiction of the main parenchymal and ventricular structures (23,24). Furthermore, the temporal sonic window can be considered as sufficient when contralateral skull and ipsilateral lesser sphenoid wing are insonated as a thick and continuous hyperechogenic structure (24) as seen in the case presented herein. The other advantages of TCCS over TCD include, but are not limited to, easier vessel localization and discrimination, Doppler angle correction, and direct imaging of cerebral parenchyma for other pathologies (25). The presented case highlights an additional aspect of TCCS in brain death diagnosis, the verification of sufficiency of acoustic bone windows in the setting of absent intracranial Doppler signals. It is important to note that point-of-care ultrasonography devices routinely equipped with phased-array 2- to 3-MHz sector transducers and proper software that enable performing TCCS but not TCD, are becoming increasingly available in ICU environments. Therefore, familiarity of ICU physicians to this additional potential for TCCS in brain death confirmation is important. Properly- organized studies are now required to test the sensitivity and specificity of our observation in confirming brain death diagnosis.
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Rev. Bras. Geof.  vol.23 número3

Rev. Bras. Geof. vol.23 número3

ABSTRACT. In the present Dissertation we studied aspects related to the CRS stack in seismic reflection data for the simulation of zero offset sections based on multi-coverage data. Although this method has its take off before, we may consider its academic initiation with M ¨uller (1998). Therefore, this staking method is rather new, and it has shown to have superior properties over the conventional NMO/DMO stack processes (Trappe et al., 2001). The CRS stack method has several fundamental properties. A first one is that the staking operator is represented by a surface, instead of a line trajectory, that approximates the travel times of primary reflections in the neighborhood of a central ray (here the central ray is the normal ray) based on the paraxial ray theory. Second, for the model undertaken (2-D and flat surface), this operator is controlled by three parameters: (1) the emergence angle of the normal ray (β 0 ); (2) the radius of curvature of the NIP wave (R N I P ); and (3) the radius of curvature of the N wave (R N ). Third, the method does not require the macro-velocity model, contrary to the conventional stack methods, but only the velocity close to the surface. We studied relevant concepts related to the following problems: (1) geological (stratigraphic, structural, tectonic and petroliferous) related to the Solim ˜oes sedimentary basin; (2) physics of the vertical and horizontal resolutions; (3) time-space discretization of the multi-coverage cube. The objective is to understand the discretization effects due to the time-space sampling, due to the seismic survey parameters, and due to the panel selection from the multi-coverage cube. Effects related to the stack windows are analyzed on the sensibility function, defined as the function obtained by the first order derivative of the hyperbolic and parabolic transit time functions with respect to the 4 parameters of the stacking operator: β 0 , R N I P , R N , and v 0 (the velocity close to the surface reference point x 0 ). The stacking is analyzed as optimization problem (surface fitting, instead of curve fitting), and includes the physical concept of the Projected Fresnel Zone. This concept is a natural integrant of the paraxial ray theory, and it serves to spatially gate the observed data to be fit. From this point of view, the contour maps of the unitary covariance matrix of the 4 parameters in reference serves to analyze the correlation among these parameters. These topics constitute basic and fundamental concepts for the CRS stack, to contribute to the determination of the processing windows, and participates on the optimization process in the search of 4 parameters from the multi-coverage cube that control the stack operator.
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The effect of desflurane on neuronal communication at a central synapse.

The effect of desflurane on neuronal communication at a central synapse.

Information theory can be used to estimate the amount of information transmitted by neurons. In this context, the correlation between a set of input stimuli and output responses allows to quantify the information conveyed by neurons [16]. In order to estimate the level of correla- tion, time windows of neuronal responses can be divided into temporal bins, to be further digi- tized in dependence on the presence of a spike (Fig 1B). The resulting sequence of temporal digits can be considered as a binary word. Neurons respond to input stimuli with a variety of binary words generating, as a whole, the neuronal vocabulary. The largest the vocabulary, the richest the conveyed information. Nevertheless, a reliable communication is ensured by a sig- nificant correlation between the output word and the input stimuli. The estimation of the cor- relation degree can be performed by calculating “response entropy” [13], which represents the variability of neuronal responses to a set of input stimuli. The largest this entropy the higher the capability of a system to communicate. Stochastic neurotransmitter release, non-linear in- tegration mechanisms and spontaneous firing introduce variability in output responses when repeatedly presenting the same input. This, in turn, introduces a systematic error that needs to be accounted for and that can be calculate by “noise entropy” [13]. MI is obtained by subtract- ing “noise entropy” from “response entropy” and it quantifies how robust to noise is the infor- mation conveyed by neural activity [15]. Given these premises, MI is measured in bits and can be calculated through the following equation:
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SPATIAL AND TEMPORAL ANALYSIS OF HUMAN MOVEMENTS AND APPLICATIONS FOR DISASTER RESPONSE MANAGEMENT UTILIZING CELL PHONE USAGE DATA

SPATIAL AND TEMPORAL ANALYSIS OF HUMAN MOVEMENTS AND APPLICATIONS FOR DISASTER RESPONSE MANAGEMENT UTILIZING CELL PHONE USAGE DATA

As cell phone usage becomes a norm in our daily lives, analysis and application of the data has become part of various research fields. This study focuses on the application of cell phone usage data to disaster response management. Cell phones work as a communication link between emergency responders and victims during and after a major disaster. This study recognizes that there are two kinds of disasters, one with an advance warning, and one without an advance warning. Different movement distance between a day with a blizzard (advanced warning) and a normal weather day was identified. In the scenario of a day with an extreme event without advanced warning (earthquake), factors that alter the phone users' movements were analyzed. Lastly, combining both cases, a conceptual model of human movement factors is proposed. Human movements consist of four factors that are push factors, movement-altering factors, derived attributes and constraint factors. Considering each category of factors in case of emergency, it should be necessary that we prepare different kinds of emergency response plans depending on the characteristics of a disaster.
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Fpga As A Part Of Ms Windows Control Environment

Fpga As A Part Of Ms Windows Control Environment

The first experiments related to Windows timer message have been tested. The periods of the timer is set to 100 ms or 10 ms. For both experiments the several individual tasks were running concurrently. It means that during the experiments MS Windows was heavy loaded.

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A biased-randomized heuristic for the home healthcare routing problem

A biased-randomized heuristic for the home healthcare routing problem

The first works concerning the HHRP were published between 1998 and 2006 and addressed the problem in a national context and proposed decision support systems (DSS) that integrated GIS technology. The first one was published in 1998 by Begur et al., [7]. They developed a DSS for the Visiting Nurse Association, in USA, to help them planning the allocation of nurses to patients and determine the daily visits sequence for each nurse. The DSS routing software is based on a well-known routing heuristic and provides simultaneously the assignment of patients and the routing for each nurse that minimizes the total travel time. Later in 2006, Bertels and Fahle [8] combined different meta-heuristics and exact approaches to address the nurse rostering problem and routing decisions taking into account patients and nurses preferences, legal aspects, nurses’ qualifications, ergonomics, and other aspects. The developed algorithms were embedded into a DSS, which according to the authors can handle most real-world HHRPs. In the same year, Eveborn et al. [9] developed a different DSS, this time for a Swedish HHRP. In order to daily plan workers scheduling and patients visits, they developed an heuristic based on the matching and set partitioning problems where previously designed schedules were allocated to workers assuring that all patients were visit exactly once.
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