Time windows

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Predicting progression of mild cognitive impairment to dementia using neuropsychological data: a supervised learning approach using time windows

Predicting progression of mild cognitive impairment to dementia using neuropsychological data: a supervised learning approach using time windows

[33, 34]. Eskildsen et al. [34], homogenized the converter MCI group regarding the time to conversion, using the cortical thickness of anatomical MR images collected at 36, 24, 12 and 6 months before conversion to create the learn- ing examples. Similarly, Cabral et al. [33] created five groups with PDF-PET images collected at 24, 18, 12, 6 and 0 months before conversion. These converting MCI groups, along with the single non-converting MCI group, were fed to machine learning classifiers to perform prognostic. An overall finding was the enhancement of the evaluation met- rics with the decrease of the temporal distance to the con- version event. Despite the relevance of this approach, it has been mostly explored with neuroimaging data. We believe that this question is transversal to all biomarker research and thus we performed a similar study using neuropsycho- logical data. To our knowledge, this is the first study using neuropsychological data to predict conversion within a Time Windows approach. We also used the strategy presented in previous works [33, 34] with our data, for sake of comparability. The outcome is shown in appen- dix [See Additional file 3]. Replicating the methodology pursuit by [33, 34] with our data benefits from a longer follow-up period.
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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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Optimized Crossover Genetic Algorithm for Vehicle Routing Problem with Time Windows

Optimized Crossover Genetic Algorithm for Vehicle Routing Problem with Time Windows

The Vehicle Routing Problem with Time Windows (VRPTW) which is an extension of Vehicle Routing Problems (VRPs) arises in a wide array of practical decision making problems. Instances of the VRPTW occur in rail distribution, school bus routing, mail and newspaper delivery, airline and railway fleet routing and etc. In general the VRPTW is defined as follows: given a set of identical vehicles V = {1, 2, … , K} , a central depot node, a set of customer nodes

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A Clustering Approach for Vehicle Routing Problems with Hard Time Windows

A Clustering Approach for Vehicle Routing Problems with Hard Time Windows

The Vehicle Routing Problem (VRP) is a well known combinatorial optimization problem and many studies have been dedicated to it over the years since solving the VRP optimally or near-optimally for very large size problems has many practical applications (e.g. in various logistics systems). Vehicle Routing Problem with hard Time Windows (VRPTW) is probably the most studied variant of the VRP problem and the presence of time windows requires complex techniques to handle it. In fact, finding a feasible solution to the VRPTW when the number of vehicles is fixed is an NP-complete problem. However, VRPTW is well studied and many different approaches to solve it have been developed over the years.
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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

This work presented the vehicle routing optimization system developed to be integrated with an existing ERP. The optimization procedure takes into consideration the need for a near real-time routing solution under dynamic orders and interactions with the system administrator. In this sight, this work described the interactions and dependencies between the system’s four main components, namely: i3FR-Opt (where the computation of the routes is done), the i3FR-Hub (implementing a channel to all the communications inside the system and to the exterior), the i3FR-DB (provider of local storage to the information relevant to the optimization procedure), and i3FR-Maps (a cartography subsystem of routing informations). With this structure it is possible to deal with late orders and different states for the routes, which allows to do a phased picking and loading of the vehicles. As mere examples, some results for the Algarve’s region were presented showing different solution depending on the time windows restrictions.
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en 0104 530X gp 0104 530X1767 16

en 0104 530X gp 0104 530X1767 16

The problem can be described from its main components: different products, heterogeneous leet, scattered offshore platforms and terminals along the coast. One of the main challenges faced by the maritime transport operation of offshore oil is the scheduling of ships to meet a set of move requests with origins, destinations and pre-established amount of products, which were deined by the logistics’ tactical planning. Pickups at platforms and deliveries at terminals should be performed at predeined time windows over a planning time horizon (e.g., several days to a few weeks). An important aspect of the problem is the consideration of oil inventory on platforms and terminals, an element which is dealt implicitly in this model through the time windows. These time windows are deined in a more aggregated level planning, where the variations and limitations of oil inventory are considered. Platforms hold their own inventory, which may not exceed a speciied maximum operating limit (called “top” by the operators), since it results in a halt of platform production and generates prohibitive opportunity costs. This situation arises as a major concern for the company’s decision-makers. These tops of the platforms are strictly considered when determining the
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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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en 0104 530X gp 0104 530X2359 15

en 0104 530X gp 0104 530X2359 15

In practical terms, the problem involves two stages: irst, the customers must be clustered around parking locations; then, routes must be designed to visit the deined clusters. Vehicle capacity, time windows and available deliverymen constraints must be satisied while the total cost is minimized (vehicle usage, deliverymen assignment and traveled distance costs). Nevertheless, given the complexity of the complete problem, clustering and routing stages are addressed separately (Senarclens de Grancy & Reimann, 2014). Therefore, regarding the VRPTWMD, it is assumed that the clustering stage is performed in advance, thus each cluster has its predeined parking location, cumulated demand and service time, which includes the transportation of the goods from the parking location to the customers of the cluster.
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Nmnat1-Rbp7 Is a Conserved Fusion-Protein That Combines NAD+ Catalysis of Nmnat1 with Subcellular Localization of Rbp7.

Nmnat1-Rbp7 Is a Conserved Fusion-Protein That Combines NAD+ Catalysis of Nmnat1 with Subcellular Localization of Rbp7.

The different time windows of embryonic expression and tissue specific differences in the adult expression demonstrated an independent regulation of zebrafish nmnat1 , nmnat1-rbp7a and r[r]

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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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Temporal integration windows for naturalistic visual sequences.

Temporal integration windows for naturalistic visual sequences.

In order to perceive coherent objects and events, the brain integrates incoming sensory information over time, over space and across sensory modalities. It is known that temporal integration mechanisms operate across multiple timescales [1]. Integration windows of around 100–150 ms are found in various paradigms, including backward masking and motion integration [4]. Similar- ly, a number of other studies have reported integration windows of around 300 ms for phenomena such as apparent motion, the attentional blink and inhibition of return [33–35]. However, one of the most apparent, yet mysterious features of the stream of consciousness is that there is an integrated subjective present, which has been estimated to extend for around 2 to 3 seconds [5,21]. Most studies of conscious awareness have focused on much shorter time windows involved in tasks such as detection of a single stimulus. In contrast, the subjective present seems to involve an aspect of consciousness that is extended in time. Here, we examined the role of this time window in our understanding of a complex, multidimensional stimulus that is more consistent with our subjective experiences of the world. Overall, these results suggest that a function of this 2–3 second window may be to provide a stable and coherent representation of events in a complex, ever-changing world.
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Time- and task-dependent non-neural effects of real and sham TMS.

Time- and task-dependent non-neural effects of real and sham TMS.

Previous work has shown that the clicking sound of a TMS pulse can facilitate target detection when applied prior to or in close temporal proximity of a target stimulus, primarily by acting as a warning signal and due to inter-sensory facilitation, respectively [5–9,16,17]. Here, we investigated the non-neural effects of TMS for a broad range of TMS time windows including pre- and post-stimulus stimulation. To begin with, our results replicate earlier findings of pre-stimulus facilitation. A TMS pulse that is administered prior to a stimulus provides temporal information and, consequently, increases the readiness to respond resulting in decreased reaction times. Additionally, we found impaired task performance at post- stimulus time windows. Reaction times were considerably prolonged when the TMS pulse occurred late during a trial; probably due to expectancy violations that caused participants to ‘wait’ for the TMS pulse (as suggested, but not systematically investigated, by [10]).
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Fire, fuel composition and resilience threshold in subalpine ecosystem.

Fire, fuel composition and resilience threshold in subalpine ecosystem.

To remove the autocorrelation in the macroremain influx series we deconstructed the time series into high- (Figure 1G,H) and low- frequency trend (Figure 1I, J) and residual components (Figure 1K,L) using LOESS [50]. The high-frequency trend in macroremain series is found by LOESS smoothing with a 500 years’ time window, here supposed to be large enough to filter high-frequency component. The high-frequency trend is removed, and the remainder smoothed to find low-frequency trend. Macroremain influx residuals from the high plus low-frequency trend fit are used as independent samples to perform SEA (Figure 1K and 1L). To test the response of detrended macroremain influx series to multiple fires, SEA involves sorting data following time windows dependent on a key-date (here fire events) to synchronize and compare the means of those time windows. This method involves a simple compositing (averaging) of different signals to detect deviations from the background rate [16,17]. For each 15- year fire event, a 240-year window was selected with 90 years before and 150 after the fire event (17 data points). A window of this size should be large enough to detect any significant response to fire events. Monte Carlo resampling techniques, involving randomly picking fire events from the chronology (1000 repetitions) was used to estimate the 95 and 99% confidence intervals (CI) around the averaged macroremain influx values [51]. To highlight the response pattern of taxa to fire, SEA composites were displayed as anomalies using the following transformation:
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European Journal of Operational Research 245 (2015) 719–730 Contents lists available at ScienceDirect

European Journal of Operational Research 245 (2015) 719–730 Contents lists available at ScienceDirect

A particular feature of our case study is the simultaneous em- ployment of specialised human resources. Anaesthetists, for instance, are identified due to specialities, training skills and availabilities. An anaesthetist has his/her own time windows. Each surgery is associ- ated with a subset of anaesthetists able to perform that intervention. An anaesthetist can perform more than one intervention simultane- ously depending upon the room in which the surgeries are taking place. Thus, the simultaneous employment of specialised human re- sources is constrained by room compatibilities. This leads to another decision to be made jointly with assigning and scheduling surgeries, as anaesthetists must be assigned and scheduled according to surgery requirements and subject to room compatibilities and to their own time windows. The objective is to maximise the use of the operating rooms. In fact, recent surveys list a number of objectives studied in the literature including minimisation of costs or makespan, and maximi- sation of throughput or utilisation (Cardoen et al., 2010; Guerriero & Guido, 2011; May et al., 2011). In our case, the manager of the hospital where the study was conducted suggested the maximisation of the utilisation of the operating rooms.
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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.

Este trabalho estuda a implementação de heurísticas e da metaheurística scatter search (SS) em um proble- ma de roteirização de veículos com frota heterogênea, janelas de tempo e entregas fracionadas (heterogeneous fleet vehicle routing problem with time windows and split deliveries – HFVRPTWSD). O HFVRPTWSD é uma combinação do problema de roteirização com frota he- terogênea (heterogeneous fleet vehicle routing problem – HFVRP), problema de roteirização de veículos com ja- nelas de tempo (vehicle routing problem with time windo- ws – VRPTW) e problema de roteirização com entregas fracionadas (vehicle routing problem with split deliveries – VRPSD). O problema é baseado em um único centro de distribuição (CD), a demanda dos clientes pode ser maior que a capacidade dos veículos e, além das restrições de janelas de tempo, há também restrições de capacidade dos veículos e acessibilidade (alguns clientes não podem ser atendidos por alguns veículos).
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A biased-randomized heuristic for the home healthcare routing problem

A biased-randomized heuristic for the home healthcare routing problem

Firstly a morning solution is created by applying the SR-GCWS-CS routing algorithm and assuring that time windows are met. At this first step, only the patients who have to be visited in the morning are considered. Then, the morning solution is used as a template for the afternoon solution, assuring that patients needing more than one visit will be assigned to the same team. Those patients needing only one visit are removed from the route since they have already been visited. The next step inserts the patients who only need to be visited during the afternoon. They are added to the route with the minimum inserting time and assuring feasibility concerning the time windows. Lastly, those patients who have no constraints regarding the visiting period are inserted in one route again following a minimum insertion criteria and assuring the solution feasibility.
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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

Table 2 shows that most of the generated dynamic datasets fail to cover a good range of static instances percentage. The only two exception being Li and Lim (2003) by Fabri and Recht (2006) and by Pureza and Laporte (2008). The method proposed by Pankratz (2005) does not generate any static instance. However, in his work some additional parameters are used to ad- dress this condition, if needed. It is believed that this side effect is also caused because of the use of pickup and delivery time windows limits combined with the use of static instances that have an accumulated distribution of these values, especially at the beginning of the planning horizon. Therefore, when using dynamization methods, care must be taken that they do not generate too many static requests, which can hinder the analysis of algorithms made to deal with dynamic requests.
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Aquisição de dados usando Logo e a porta de jogos do PC.

Aquisição de dados usando Logo e a porta de jogos do PC.

Desrevemos um sistema de aquisi ~ ao de dados baseado na porta de jogos do IBM-PC om.. plataforma Windows.[r]

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Fpga As A Part Of Ms Windows Control Environment

Fpga As A Part Of Ms Windows Control Environment

The attention is focused on the Windows operating system (OS) used as a control and mea- surement environment. Windows OS due to extensions becomes a real-time OS (RTOS). Benefits and drawbacks of typical software extensions are compared. As far as hardware solutions are concerned the field programmable gate arrays FPGA technology is proposed to ensure fast time-critical operations. FPGA-based parallel execution and hardware implemen- tation of the data processing algorithms significantly outperform the classical microprocessor operating modes. Suitability of the RTOS for a particular application and FPGA hardware maintenance is studied.
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MALWARE, O VÍRUS QUE OCULTA ARQUIVOS: como recuperar arquivos afetados por esse vírus de computador :: Brapci ::

MALWARE, O VÍRUS QUE OCULTA ARQUIVOS: como recuperar arquivos afetados por esse vírus de computador :: Brapci ::

Neste método de recuperação dos documentos, será utilizada a ferramenta “opções de pasta e arquivos” do Explorer do Windows; que possibilita o usuário configurar as pastas de sua máquina da forma desejada, com um ou dois cliques para abrir pastas/documentos, mostrar/não mostrar arquivos ocultos, ou restaurar as configurações padrões de seu sistema operacional. Juntamente com essa ferramenta é aplicado um software livre denominado FixPolicies que tem como finalidade mostrar todos os arquivos e pastas ocultas no computador que possivelmente estejam corrompidos e que não possam ser visualizadas apenas com a ferramenta descrita acima.
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