327315
A Survey on Vehicle Routing Problem with Loading Constraints
In the classical Vehicle Routing Problem (VRP), a fleet of vehicles is available to serve a set of customers with known demand. Each customer is visited by exactly one vehicle as well as the objective is to minimize the total distance or the total charge incurred. Recent years have seen increased attention on VRP integrated with additional loading constraints, known as 2L-CVRP or 3L-CVRP. In this paper we present a survey of the state-of-the-art on 2L-CVRP/3L-CVRP.
39897206
A Compromised Large-Scale Neighborhood Search Heuristic for Cargo Loading Planning
In this work, we propose a compromised large-scale neighborhood, which is embedded in simulated annealing to solve a cargo loading planning problem arising in logistics industry. It is "compromised" because it makes a tradeoff between the extensive backward checking work incurred in traditional subset-disjoint restriction and the possible infeasibility resulting from the relaxing the restriction. Extensive experiments have shown the competitive advantages of the heuristic approach. The proposed neighborhood search method is generally applicable.
44734123
Meta-heuristic Algorithm for the Transshipment Problem with Fixed Transportation Schedules
In this work, we develop an efficient meta-heuristic genetic algorithm for a different type of transshipment problem with supplier and customer time windows, where flow through the crossdock (a kind of transshipment center) is constrained by fixed transportation schedules and crossdocks capacities, and which was proved to be NP -complete in the strong sense. And computational experiments are conducted to show the proposed heuristic outperforms CPLEX.
5216004
Flexible Demand Assignment Problem
This paper proposed a state-of-the-art local search for solving Flexible Demand Assignment problem (FDA) which considers the balance between revenue and cost in demand assignment. Different than the published studies, our research splits the FDA problem into three core subproblems as operators for neighborhood construction. The three specified subproblems One Bin Repack, Two Bins Repack and Unpack are proposed completely based on mathematical modelling, computational complexity, executive conditions and greedy solving methods. Benchmark experimental results have shown that the proposed local search improved to the best published heuristics by 2.34%.
32718924
k-Center Problems with Minimum Coverage
The k-center problem is a well-known facility location problem and can be described as follows: Given a complete undirected graph G=(V,E), a metric d:V×V→ℝ + and a positive integer k, we seek a subset U ⊆ V of at most k centers which minimizes the maximum distances from points in V to U. Formally, the objective function is given by: 
 
$$ \textstyle\min_{U\subseteq V,|U|\leq k}\max_{v\in V}\min_{r\in U}d(v,r).$$ 
 
As a typical example, we may want to set up k service centers (e.g., police stations, fire stations, hospitals, polling centers) and minimize the maximum distances between each client and these centers. The problem is known to be \(\mathcal{NP}\)-hard [2].
23454249
A compromised large-scale neighborhood search heuristic for capacitated air cargo loading planning
Cost effectiveness is central to the air freight forwarders. In this work, we study how an air freight forwarder should plan its cargo loading in order to minimize the total freight cost given a limited number of rented containers. To solve the problem efficiently for practical implementation, we propose a new large-scale neighborhood search heuristic. The proposed large-scale neighborhood relaxes the subset-disjoint restriction made in the existing literature; the relaxation risks a possibility of infeasible exchanges while at the same time it avoids the potentially large amount of checking effort required to enforce the subset-disjoint restriction. An efficient procedure is then used to search for improvement in the neighborhood. We have also proposed a subproblem to address the difficulties caused by the fixed charges. The compromised large-scale neighborhood (CLSN) search heuristic has shown stably superior performance when compared with the traditional large-scale neighborhood search and the mixed integer programming model.
35474967
Handling Grammatical Errors, Ambiguity and Impreciseness in GIS Natural Language Queries
A natural language query interface is very desirable for a geographic information system (GIS). It converts natural language queries (sentences) into a formal query language. A key task in building a natural language query interface is handling uncertainty and impreciseness. Grammatical errors and parsing ambiguity cause uncertainty. A natural language query may contain imprecise terms that have to be processed before an executable query can be generated. In this paper, a three–step technique is presented that can be used to correct grammatically incomplete natural language queries, solve parsing ambiguity, and translate imprecise conditions into executable selection conditions.
58278482
Adaptive Meeting Scheduling for Large-Scale Distributed Groupware
This paper introduces a novel approach of collective scheduling among a community of distributed users. This approach, named Distributed Adaptive Scheduling (DAS), deploys flexible, lightweight agents to quickly find and suggest suitable solutions of scheduling for a large number of users. The DAS agents can move from one machine to another to co-ordinate mutually acceptable solutions for a proposed meeting. They also possess behavioural intelligence, by making adaptive decisions about next actions according to current environment and conditions. As a consequence, quick and efficient scheduling can be achieved for users located at different places. Experimental results have proved that DAS is especially suitable for large-scale distributed scheduling, and scheduling with complex calendars. The DAS approach has been successfully integrated with a personal assistant agent platform to provide completely automatic meeting scheduling for both stationary and mobile users.
39488688
Modeling of power electronics for simulation based analysis of power systems
Given the increased penetration of power electronic converters in power systems it is necessary to study their impact in the system operation. In order to achieve that goal the power converters must be appropriately modeled in simulation or analytical studies. This paper reviews the modeling requirements and characteristics of power electronic converter models for system studies. Several models of the equipment used in a ship power system are described. The use of these models in simulation based system studies is discussed in the paper. Stability analysis is used as example for that discussion. The models are grouped into categories based on their degree of detail and use. Moreover, the validity and computational requirements of those models are also discussed.
14622522
Short-Term Traffic Flow Prediction Based on Parallel Quasi-Newton Neural Network
Identifying and predicting the situation of traffic flow play an important role in traveler information broadcast and real-time traffic control. In this paper, a short-term traffic flow prediction model based on the parallel self-scaling quasi-Newton (SSPQN) neural network is presented. In this method, a set of parallel search directions are generated at the beginning of each iteration. Each of these directions is selectively chosen from a representative class of quasi-Newton (QN) methods. Inexact line searches are then carried out to estimate the minimum point along each search direction. Experimental and analytical results demonstrate the feasibility of applying SSPQN to traffic flow prediction and prove that it can better satisfy real-time demand of traffic flow prediction.
17387860
On the competitiveness of on-line real-time task scheduling
With respect to on-line scheduling algorithms that must direct the service of sporadic task requests we quantify the benefit of clairvoyancy, i.e., the power of possessing knowledge of various task parameters of future events. Specifically, we consider the problem of preemptively sheduling sporadic task requests in both uni- and multi-processor environments. If a task request is successfuly scheduled to completion, a value equal to the task's execution time is obtained; otherwise no value is obtained. We prove that no on-line scheduling algorithm can guarantee a cumulative value greater than 1/4th the value obtainable by a clairvoyant scheduler; i.e., we prove a 1/4th upper bound on the competitive factor of on-line real-time schedulers. We present an online uniprocessor scheduling algorithm TD1 that actually has a competitive factor of 1/4; this bound is thus shown to be tight. We further consider the effect of restricting the amount of overloading permitted (the loading factor), and quantify the relationship between the loading factor and the upper bound on the competitive factor. Other results of a similar nature deal with the effect of value densities (measuring the importance of type of a task). Generalizations to dual-processor on-line scheduling are also considered. For the dual-processor case, we prove an upper bound of 1/2 on the competitive factor. This bound is shown to be tight in the special case when all the tasks have the same density and zero laxity.