西九文化区

正OMA发展西九文化区,必须面对一项挑战:将一个盛载政府极大抱负,以及持分者多元利益的超大型多用途项目,转化成一个既有趣又严肃、既有规划又允许即兴、既中国化又国际化的文化区。这个文化区规模庞大,但不失亲密融洽的感觉;富地标性,但十分谦和;容易理解,却能带来惊喜。为避免造成过分冲击,OMA采纳了一种每个香港市民都熟悉的建筑类型作为方案的发展     

An integrated implementation framework for compile‐time metaprogramming

Compile‐time metaprograms are programs executed during the compilation of a source file, usually targeting to update its source code. Even though metaprograms are essentially programs, they are typically treated as exceptional cases without sharing common practices and development tools. Toward this direction, we identify a set of primary requirements related to language implementation, metaprogramming features, software engineering support, and programming environments and elaborate on addressing these requirements in the implementation of a metaprogramming language. In particular, we introduce the notion of integrated compile‐time metaprograms, as coherent programs assembled from specific metacode fragments present in the source code. We show the expressiveness of this programming model and illustrate its advantages through various metaprogram scenarios. Additionally, we present an integrated tool chain, supporting full‐scale build features and compile‐time metaprogram debugging. Copyright © 2013 John Wiley & Sons, Ltd.     

Multiple Phase Neighborhood Search-GRASP for the Capacitated Vehicle Routing Problem

Greedy Randomized Adaptive Search Procedure (GRASP) has been proved to be a very efficient algorithm for the solution of the Traveling Salesman Problem. Also, it has been proved that expanding the local search with the use of two or more different local search strategies helps the algorithm to avoid trapping in a local optimum. In this paper, a new modified version of GRASP, called Multiple Phase Neighborhood Search-GRASP (MPNS-GRASP), for the solution of the Vehicle Routing Problem is proposed. In this method, a stopping criterion based on Lagrangean Relaxation and Subgradient Optimization is utilized. In addition, a different way for expanding the neighborhood search is used based on a new strategy, the Circle Restricted Local Search Moves strategy. The algorithm was tested on two sets of benchmark instances and gave very satisfactory results. In both sets of instances the results have solution qualities with average values near to the optimum values and in a number of them the algorithm finds the optimum. The computational time of the algorithm is decreased significantly compared to other heuristic and metaheuristic algorithms due to the fact that the new strategy, the Expanding Neighborhood Search Strategy, is used.     

PoweRGen: A power-law based generator of RDFS schemas

As the amount of RDF datasets available on the Web has grown significantly over the last years, scalability and performance of Semantic Web (SW) systems are gaining importance. Current RDF benchmarking efforts either consider schema-less RDF datasets or rely on fixed RDFS schemas. In this paper, we present the first RDFS schema generator, termed PoweRGen, which takes into account the features exhibited by real SW schemas. It considers the power-law functions involved in (a) the combined in- and out-degree distribution of the property graph (which captures the domains and ranges of the properties defined in a schema) and (b) the out-degree distribution of the transitive closure (TC) of the subsumption graph (which essentially captures the class hierarchy). The synthetic schemas generated by PoweRGen respect the power-law functions given as input with an accuracy ranging between 89 and 96%, as well as, various morphological characteristics regarding the subsumption hierarchy depth, structure, etc.