9824531
A Reverse Glue Approach to Automated Construction of Multi-Piece Molds
Mold design can be a difficult, time-consuming process. Determining how to split a cavity into multiple mold pieces (e.g., core, cavity) manually can be a tedious pro This paper focuses on the mold construction step of the automated mold design pr By investigating glue operations and its relations with parting faces, an approach b on a new reverse glue operation is presented. The key to the reverse glue operatio generate parting faces. A problem definition of parting face generation for a regio provided. Correspondingly, three face generating criteria are identified. Based on parting lines of a region, our algorithms to generate the parting faces are presented. mold construction algorithms for two-piece molds and multi-piece molds are also sented with brief discussions. Some industrial examples are provided which illustra efficiency and effectiveness of our approach. We tested our mold designs by fabri stereolithography mold inserts (a rapid tooling method) and molding parts. @DOI: 10.1115/1.1603308 #
15013820
A Region Based Method to Automated Design of Multi-Piece Molds with Application to Rapid Tooling
Particularly for rapid tooling applications, delivering prototype parts with turn-aroun times of less than two weeks requires fast, proven mold design methods. We pre region-based approach to automated mold design that is suitable for simple twomolds (consisting of core and cavity), as well as molds with many additional mo sections. In our region-based approach, part faces are partitioned into regions, ea which can be formed by a single mold piece. The basic elements of our approac concave regions (generalized pockets) and convex faces since these elements are to the identification of regions. This paper focuses on the initial steps of automated design, including a problem formulation, methods for identifying the basic elements part faces, and combining them into regions. By seeking to minimize the number of pieces, different partitions of faces into regions are explored until the smallest numb regions is found. During this process, a linear programming problem is adopted finding a satisfactory parting direction of a region. Algorithms are presented for region generating and combining process. Our approach is illustrated with severa amples of industrial injection molded parts. @DOI: 10.1115/1.1505030 #
14925300
A Taxonomy of Data Prefetching Mechanisms
Data prefetching has been considered an effective way to mask data access latency caused by cache misses and to bridge the performance gap between processor and memory. With hardware and/or software support, data prefetching brings data closer to a processor before it is actually needed. Many prefetching techniques have been proposed in the last few years to reduce data access latency by taking advantage of multi-core architectures. In this paper, we propose a taxonomy that classifies various design concerns in developing a prefetching strategy. We discuss various prefetching strategies and issues that have to be considered in designing a prefetching strategy for multi-core processors.
38801994
Generalized Q-S (lag, anticipated and complete) synchronization in modified Chua's circuit and Hindmarsh-Rose systems
Abstract Based on symbolic computation system Maple and Lyapunov stability theory, a systematic, powerful and concrete scheme is extended to study the generalized Q – S (lag, anticipated and complete) synchronization between two identical modified Chua’s circuit with different initial values and between two different chaotic systems: Hindmarsh–Rose system and modified Chua’s circuit. Numerical simulations are used to verify the effectiveness of the obtained controller.
37352290
Comparison of Two Fitness Functions for GA-Based Path-Oriented Test Data Generation
Automatic path-oriented test data generation is not only a crucial problem but also a hot issue in the research area of software testing today. As a robust metaheuritstic search method in complex spaces, genetic algorithm (GA) has been used to path-oriented test data generation since 1992 and outperforms other approaches. A fitness function based on branch distance (BDBFF) and another based on normalized extended Hamming distance (SIMILARITY) are both applied in GA-based path-oriented test data generation. To compare performance of these two fitness functions, a triangle classification program was chosen as the example. Experimental results show that BDBFF-based approach can generate path-oriented test data more effectively and efficiently than SIMILARITY- based approach does.
46139740
Automatic Path-Oriented Test Data Generation Using a Multi-population Genetic Algorithm
Automatic path-oriented test data generation is an undecidable problem and genetic algorithm (GA) has been used to test data generation since 1992. In favor of MATLAB, a multi-population genetic algorithm (MPGA) was implemented, which selects individuals for free migration based on their fitness values. Applying MPGA to generating path-oriented test data generation is a new and meaningful attempt. After depicting how to transform path-oriented test data generation into an optimization problem, basic process flow of path-oriented test data generation using GA was presented. Using a triangle classifier as program under test, experimental results show that MPGA based approach can generate path-oriented test data more effectively and efficiently than simple GA based approach does.
40119866
A fault tolerant topology control in wireless sensor networks
Summary form only given. Topology control of wireless sensor networks (WSNs) is a key design challenge in terms of extending the lifetime of the network. The paper presents a fault tolerant topology control by adding necessary redundant nodes to the network's simple communication backbone, which results a higher vertex connectivity degree. It provides not only fault tolerance for unreliable node failure, but also support for upper level protocols. The paper also identifies several factors and synchronization methods which may affect the redundant node selection. A simulation study shows the improvement of network lifetime with a desired vertex connectivity degree.