We introduce a robust and shallow approach for grammatical role labeling (dependency labeling) where data-driven and theory-driven aspects are combined in a principled way. A classifier provides empirically justified ...
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We introduce a robust and shallow approach for grammatical role labeling (dependency labeling) where data-driven and theory-driven aspects are combined in a principled way. A classifier provides empirically justified weights, linguistic theory contributes well-motivated global restrictions, both are combined under the regiment of optimization. The empirical results of our approach are promising. However, we have made idealized assumptions (small inventory of dependency relations and treebank-derived chunks) that clearly must be replaced by a realistic setting.
For a simple, undirected, connected graph G, a function h: V(G) -> {0, 1, 2} which satisfies the following conditions is called a weakly connected Roman dominating function (WCRDF) of G with weight h(V) = Sigma(p i...
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For a simple, undirected, connected graph G, a function h: V(G) -> {0, 1, 2} which satisfies the following conditions is called a weakly connected Roman dominating function (WCRDF) of G with weight h(V) = Sigma(p is an element of V) h(p). (C1). For all q is an element of V with h(q) = 0 there exists a vertex r such that (q, r) is an element of E and h(r) = 2 and (C2). The graph with vertex set V(G) and edge set {(p, z) : h(p) >= 1 or h(z) >= 1 or both} is connected. The problem of determining WCRDF of minimum weight is called minimum weakly connected Roman domination problem (MWCRDP). In this paper, we show that MWCRDP is polynomial time solvable for bounded treewidth graphs, threshold graphs and chain graphs. We design a 2(1 + epsilon)(1 +In(Delta - 1))-approximation algorithm for the MWCRDP and show that the same cannot have (1 - delta) In vertical bar V vertical bar ratio approximation algorithm for any delta > 0 unless P = NP. Next, we show that MWCRDP is APX-hard for graphs with Delta = 4. We also show that the domination and weakly connected Roman domination problems are not equivalent in computational complexity aspects. Finally, two different integer linear programming formulations for MWCRDP are proposed.
Purpose - The purpose of this study is to address an importance of an intermodal terminal regarding container drayage trips, which have a major concern for agricultural product exporters in the Upper Great Plains. Thu...
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Purpose - The purpose of this study is to address an importance of an intermodal terminal regarding container drayage trips, which have a major concern for agricultural product exporters in the Upper Great Plains. Thus, this study aims to develop a geospatial model considering travel distance and total logistics costs for determining an alternative intermodal terminal location. Design/methodology/approach - This paper develops a spatial model integrating integer linear programming to determine an intermodal facility location that minimizes total logistics costs. This research considers travel distance and total logistics costs including highway, rail and transshipment costs. Findings - The results shows that a Dilworth, Minnesota, terminal reduces vehicle miles of travel on both the highways and rail networks and decreases system-wide total logistics costs compared to the do-nothing scenario while decreasing urban congestion costs in metropolitan areas. Research limitations/implications - The major contribution of the study is that it provides an integrated tool of spatial and economic analyses to support regional decision-making. The paper will be of interest to regional planners and to those in the private business sectors including farmers and manufacturers. The future study should address demand forecasting on the containerized freight in the region. Originality/value - The novel approach of this paper is to use a link blocking constraint, considering the directions of the freight flow in a p-hub intermodal problem.
Deposit return systems have started making their reappearance as more environmentally conscious consumers seek ways to effectively reduce their carbon footprint. An example is the management of refillable glass bottle...
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Deposit return systems have started making their reappearance as more environmentally conscious consumers seek ways to effectively reduce their carbon footprint. An example is the management of refillable glass bottles which requires a well-organized collection network with inventory management. A collection planning with an efficient algorithm and information system has to be applied. This paper investigates, using integer linear programming, a vehicle routing problem with time constraints to provide flexibility as well as priority rules to avoid inventory saturation at collection points. The model presented, based on a real-life application in the city of Lyon and surrounding areas, includes several objectives with specific assumptions. The result of the optimization is a vehicle routing plan with flexible scheduling based on time slots. Numerical experiments are conducted on instances of different scales making it possible to model the current problem as well as its future evolution. These experiments consider several instances, using a single vehicle among three vehicle types (cargo-bicycle, car and van) and a network composed of 20 stores/clients to collect bottles from. The results show the impacts of the priority rules on the solution obtained and additional indicators are proposed in order to analyze more precisely the quality of the solution in terms of financial cost and environmental impact. The proposed model and program will help make appropriate decisions in planning and scheduling the routes of the vehicles for the refillable glass bottle collection, especially in urban areas.
The present paper explores a Greek case study on optimizing the design of aviation networks under Public Service Obligations (PSO). Based on previous research on airline PSO networks applied to the case studies of the...
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The present paper explores a Greek case study on optimizing the design of aviation networks under Public Service Obligations (PSO). Based on previous research on airline PSO networks applied to the case studies of the Azores and Norway, optimization models are adapted to minimize not only the cost to the airline, but also the total social costs. Different predictive models to estimate demand are developed and included in the optimization models. It is found that after applying the developed demand and optimization models, the total network costs can be reduced significantly, compared to the actual network?s operation ranging from 4% to 20%.
Mapping a real-time embedded application onto a multiprocessor architecture under several constraints such as performance, cost, energy, and reliability is a major challenge in embedded systems. In this paper, we pres...
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ISBN:
(纸本)0780392647
Mapping a real-time embedded application onto a multiprocessor architecture under several constraints such as performance, cost, energy, and reliability is a major challenge in embedded systems. In this paper, we present an ILP (integer linear programming) based framework that maps a given application (represented as a task graph) onto an HCM (Heterogeneous Chip Multiprocessor) architecture. Our framework can be used with several objective functions such as energy, performance, and fallibility (opposite of reliability). We use Dynamic Voltage Scaling (DVS) for reducing energy consumption while we employ task duplication to minimize fallibility.
Demands for avionics Wavelength Division Multiplexing (WDM) network have been increasing dramatically in multicasting applications such as the in-flight multimedia in recent years. The topic of multicasting routing pr...
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ISBN:
(纸本)9781467316996
Demands for avionics Wavelength Division Multiplexing (WDM) network have been increasing dramatically in multicasting applications such as the in-flight multimedia in recent years. The topic of multicasting routing problem has been investigated with enthusiasm, because a proper design of routing can not only make full use of the resource, but also improve the performance of networks. However, different from other WDM networks like the backbone WDM network or the WDM LAN, the requirements of reliability and predictability of avionics WDM network are far stricter. In this article, we study light-trees optimization that aim to minimize the cost of the network after giving the general problem definition. In order to expand our work, we first propose the integer linear programming (ILP) algorithms for a simple situation without traffic grooming. Then we consider a more practical situation on the basis of this algorithm. By analyzing three schemes for supporting multicast connections, we select Stop-and-Go (S/G) Light-tree because it can save resource and meanwhile decrease the delay of messages. We also propose an integer linear programming algorithm for this scenario. This algorithm focuses on: 1) the delay constraint, which means sessions need to arrive at destination in limited time;2) the load constraint to meet the requirement of reliability;3) sparse splitting constraint, i.e., some switches are incapable of splitting light because of economical reason. The simulation results of WDM network show the algorithm can minimize the cost while ensure the timing requirement.
State assignment for finite state machines is a critical optimization problem in the synthesis of sequential circuits. In this paper we address the state assignment problem from a low power perspective. We experiment ...
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ISBN:
(纸本)9781424457939
State assignment for finite state machines is a critical optimization problem in the synthesis of sequential circuits. In this paper we address the state assignment problem from a low power perspective. We experiment with Boolean Satisfiability and integer linear programming techniques to solve the assignment problem where the primary goal is the reduction of switching activity during state transitions. We also detect and evaluate the use of symmetries in speeding up the search process. These techniques have been applied to the MCNC benchmark circuits and yielded promising results.
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