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141.
In today's economy, manufacturing plants must be able to operate efficiently and respond quickly to changes in product mix and demand. Therefore, this paper considers the problem of arranging and rearranging (when there are changes between the flows of materials between departments) manufacturing facilities such that the sum of the material handling and rearrangement costs is minimized. This problem is known as the dynamic facility layout problem (DFLP). In this paper, two simulated annealing (SA) heuristics are developed for the DFLP. The first SA heuristic (SA I) is a direct adaptation of SA to the DFLP. The second SA heuristic (SA II) is the same as SA I with a look-ahead/look-back strategy added. To test the performance of the heuristics, a data set taken from the literature is used in the analysis. The results obtained show that the proposed heuristics are very effective for the dynamic facility layout problem. 相似文献
142.
Refinement of packet size in low carbon bainitic steel by special thermo-mechanical control process 总被引:1,自引:0,他引:1
ChengjiaShang XueminWang ShanwuYang XinlaiHe 《北京科技大学学报(英文版)》2004,11(3):221-224
The packet size of bainitic steel can be refined by a special relaxation-precipitation-control phase transformation (RPC) technology, When processed by RPC process, the low carbon bainitic steel composes of two kinds of main intermediate transformation phases. One is ultra-fine lath-like bainitic ferrite and the lath is less than 1 tam in width and about 6 tam in length; the alignment of laths forms a refined packet, and the size of packets is about 5-7 ~am in length and about 3-4 tam in width, The other is acicular structure. The morphology and distribution of these acicular structures are influenced by relaxation process, the thin and short acicular structures cut the prior austenite grain and refine the bainitic packet size, For the optimum relaxation time, the packet size can be refined to the finest. The mechanical properties are influenced by relaxation time and the 800 MPa grade low carbon bainitic steel with excellent toughness can be obtained by RPC process, 相似文献
143.
McKay James R.; Lynch Kevin G.; Shepard Donald S.; Ratichek Sara; Morrison Rebecca; Koppenhaver Janelle; Pettinati Helen M. 《Canadian Metallurgical Quarterly》2004,72(6):967
This study of continuing care for substance dependent patients compared a telephone-based monitoring and brief counseling intervention (TEL) with 2 face-to-face interventions, relapse prevention (RP) and standard 12-step group counseling (STND). The participants were graduates of intensive outpatient programs who had current dependence on alcohol and/or cocaine. Self-report, collateral, and biological measures of alcohol and cocaine use were obtained over a 12-month follow-up. The treatment groups did not differ on abstinence-related outcomes in the complete sample (N = 359) or on cocaine use outcomes in participants with cocaine dependence (n = 268). However, in participants with alcohol dependence only (n = 91), TEL produced better alcohol use outcomes than STND on all measures examined and better outcomes than RP on some of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
This paper presents the application of a multi-scale paradigm to Chinese spoken document retrieval (SDR) for improving retrieval performance. Multi-scale refers to the use of both words and subwords for retrieval. Words are basic units in a language that carry lexical meaning, and subword units (such as phonemes, syllables or characters) are building components for words. Retrieval using subword indexing units is better than retrieval using words because of the robustness of subword units to out-of-vocabulary (OOV) words during speech recognition and ambiguities in word segmentation. Experimental results have demonstrated that subword bigrams can bring improvement in retrieval performance over words (~9.56%). Application of multi-scale fusion to SDR aims at combining the lexical information of words and the robustness of subwords. This work presents the first detailed investigation for a Cantonese broadcast news retrieval task using two different multi-scale fusion approaches: pre-retrieval fusion and post-retrieval fusion. Multi-scale retrieval using both words and syllable bigrams achieves improvement in retrieval performance (~1.90%) over retrieval on the composite scales. 相似文献
145.
Guo M Jiang XP Lam KH Wang S Sun CL Chan HL Zhao XZ 《The Review of scientific instruments》2007,78(1):016105
In this article, a multilayer piezoelectric transformer based on lead-free Mn-doped 0.94(Bi(12)Na(12))TiO(3)-0.06BaTiO(3) ceramics is presented. This piezoelectric transformer, with a multilayered construction in the thickness direction, is 8.3 mm long, 8.3 mm wide, and 2.3 mm thick. It operates in the second thickness extensional vibration mode. For a temperature rise of 20 degrees C, the transformer has an output power of >0.3 W. With a matching load resistance of 10 Omega, its maximum efficiency approaches 81.5%, and the maximum voltage gain is 0.14. It has potential to be used in low voltage power supply units such as low power adapter and other electronic circuits. 相似文献
146.
Shang De-guang Sun Guo-qin Deng Jing Yan Chu-liang 《Frontiers of Mechanical Engineering in China》2006,1(3):265-269
On the basis of the continuum fatigue damage theory, a nonlinear uniaxial fatigue cumulative damage model is first proposed.
In order to describe multiaxial fatigue damage characteristics, a nonlinear multiaxial fatigue cumulative damage model is
developed based on the critical plane approach. The proposed model can consider the multiaxial fatigue limit, mean hydrostatic
pressure and the unseparated characteristic for the damage variables and loading parameters. The recurrence formula of fatigue
damage model was derived under multilevel loading, which is used to predict multiaxial fatigue life. The results showed that
the proposed nonlinear multiaxial fatigue cumulative damage model is better than Miner’s rule. 相似文献
147.
针对低功耗和非接触式位移测量的应用需求,利用磁阻传感器,本文在传统的线性测量方法的基础上,提出了一种非线性的测量方法。设计了一个测量系统,实测结果表明该方法测量精度高、测量范围广、简单易用,也节省了成本。 相似文献
148.
针对采用JIT生产方式的主机厂要求配套厂送货及时,以及配套厂拉动单管理不科学的现状,提出了拉动单管理系统的模型结构,对功能模块进行划分,并设计实现了拉动单管理系统,较好地解决了主机厂与配套厂数据对接问题。 相似文献
149.
张羊换 《武汉理工大学学报(材料科学英文版)》2018,33(4):812-822
The La-Mg-Ni-Mn-based AB2-type La1-xCexMgNi3.5Mn0.5 (x = 0, 0.1, 0.2, 0.3, and 0.4) alloys were fabricated by melt spinning technology. The effects of Ce content on the structures and electrochemical hydrogen storage performances of the alloys were studied systematically. The XRD and SEM analyses proved that the experimental alloys consist of a major phase LaMgNi4 and a secondary phase LaNi5. The variation of Ce content causes an obvious change in the phase abundance of the alloys without changing the phase composition. Namely, with the increase of Ce content, the LaMgNi4 phase augments and the LaNi5 phase declines. The lattice constants and cell volumes of the alloys clearly shrink with increasing Ce content. Moreover, the Ce substitution for La results in the grains of the alloys clearly refined. The electrochemical tests showed that the substitution of Ce for La obviously improves the cycle stability of the as-spun alloys. The analyses on the capacity degradation mechanism demonstrate that the improvement can be attributed to the ameliorated anti-corrosion and anti-oxidation ability originating from substituting partial La with Ce. The as-spun alloys exhibit excellent activation capability, reaching the maximum discharge capacities just at the first cycling without any activation treatment. The substitution of Ce for La evidently improves the discharge potential characteristics of the as-spun alloys. The discharge capacity of the alloys first increases and then decreases with growing Ce content. Furthermore, a similar trend also exists in the electrochemical kinetics of the alloys, including the high rate discharge ability (HRD), hydrogen diffusion coefficient (D), limiting current density (IL) and charge transfer rate. 相似文献
150.
数据一致性是主备用系统必须解决的问题.目前主备系统的一致性都采用手工编程来实现,导致代码结构繁杂,且效率不高.利用VxWorks的异常处理机制,结合RISC CPU的特性,设计实现了一个数据一致性功能组件.这个组件可使数据的一致性处理自动化. 相似文献