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压制球形药包解决退模问题的技术措施
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作者 刘光烈 《爆破器材》 CAS 北大核心 1992年第6期30-31,共2页
文中简要阐述了在制备球形药包过程中,为解决压装药件的退模问题所采取的技术措施,并提出了较佳的成型底座的设计方案。
关键词 药卷药包 压制 退模 成型 测试
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含能材料柱状近净成形退模工艺仿真优化分析
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作者 聂军刚 朱宇宏 +1 位作者 袁志勇 吴进军 《锻压技术》 CAS CSCD 北大核心 2018年第9期184-188,共5页
近净成形工艺是含能材料的主要成形方式之一,当原料通过近净成形工艺成形后,为了保证退模过程中冲头受力均匀和退模过程顺利,需要对退模过程进行研究。采用通用有限元分析软件ABAQUS建立含能材料柱状近净成形有限元模型,对其退模工艺全... 近净成形工艺是含能材料的主要成形方式之一,当原料通过近净成形工艺成形后,为了保证退模过程中冲头受力均匀和退模过程顺利,需要对退模过程进行研究。采用通用有限元分析软件ABAQUS建立含能材料柱状近净成形有限元模型,对其退模工艺全过程进行仿真分析,得到了退模过程中模具和冲头的最大应力,并且给出退模过程中的退模力-冲头位移曲线。进一步分析了退模加载速度对退模力的影响,分析了两种典型的加载速度工况下的退模力。结果表明,本文建立的有限元仿真模型能够有效地模拟近净成形退模工艺,为退模工艺的相关参数设计和工程实践提供指导。 展开更多
关键词 含能材料 近净成形 退模 拟仿真 有限元分析
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模代数与普通代数的关系 被引量:2
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作者 王伶俐 陈偕雄 《杭州大学学报(自然科学版)》 CSCD 1997年第1期40-44,共5页
本文提出了模代数中的取模和退模运算,并且在此基础上指出了模代数系统和普通代数系统的反演关系,对普通代数系统也作了重新的认识,最后简略地提出了它们的一些应用.
关键词 代数 普通代数 运算 退模运算
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超高层建筑集成式电动爬升模板施工技术 被引量:1
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作者 叶巡安 《低碳世界》 2014年第05X期223-225,共3页
随着城市建筑的高速发展,可利用土地资源日益减少,超高层建筑发展成为了一个主流和社会需求,超高层施工中需采用外防护架以及模板施工,如果采用传统方式,难以在施工质量和安全上得以保证。采用集成式电动爬模施工技术,在保证施工... 随着城市建筑的高速发展,可利用土地资源日益减少,超高层建筑发展成为了一个主流和社会需求,超高层施工中需采用外防护架以及模板施工,如果采用传统方式,难以在施工质量和安全上得以保证。采用集成式电动爬模施工技术,在保证施工质量的前提下,解决防护安全隐患、液压爬模油泄露污染、楼层提升速度慢等问题。 展开更多
关键词 集成式 电动爬 退模系统 轨道 提升
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“滑空倒模”专利在施工实践中的应用 被引量:1
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作者 杨翔虎 杨晨 《江苏建筑》 2018年第5期84-86,共3页
文章通过"滑空倒模"专利的技术背景、适用范围的介绍和88m超大直径预应力筒仓的筒仓壁施工的应用实例,从滑空平台及液压系统的组装、混凝土浇筑、退模、滑空、模板复位等全部施工过程,阐述了滑空倒模的工艺原理及良好的经济... 文章通过"滑空倒模"专利的技术背景、适用范围的介绍和88m超大直径预应力筒仓的筒仓壁施工的应用实例,从滑空平台及液压系统的组装、混凝土浇筑、退模、滑空、模板复位等全部施工过程,阐述了滑空倒模的工艺原理及良好的经济效益和社会效益。 展开更多
关键词 滑空倒 筒仓壁 组装退模 滑空 复位
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盲孔砂轮成型模具结构设计的改进
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作者 闫瑞金 《哈尔滨轴承》 2004年第1期32-33,共2页
在改进了成型模具的结构之后,在手工退模条件下也可以生产粗粒度、高硬度、小外径。
关键词 盲孔砂轮 压成型 结构设计 成型 手工退模
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Web services composition with QoS bound based on simulated annealing algorithm 被引量:6
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作者 刘青 张世龙 +1 位作者 杨锐 连祥鉴 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期308-311,共4页
In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or co... In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or composite service as a quality vector,and then models the QoS(quality of service)-aware composition as a multiple criteria optimization problem in extending directed graph.A novel simulated annealing algorithm for QoS-aware web services composition is presented.A normalizing for composite service QoS values is made,and a secondary iterative optimization is used in the algorithm.Experimental results show that the simulated annealing algorithm can satisfy the multiple criteria and global QoS requirements of service consumers.The algorithm produces near optimum solution with much less computation cost. 展开更多
关键词 web services quality of service(QoS) service composition simulated annealing
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专用25t压力机的控制系统设计
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作者 石彦韬 朱齐丹 吕晓龙 《应用科技》 CAS 2017年第2期40-43,共4页
为实现液压退模系统中定程压制和定压压制两种工作模式,选择射流管型电液伺服阀驱动液压缸,利用电液伺服阀无级控制阀内开度的特性,结合位移和压力传感器,实现冲头行程和压力的反馈控制。采用PLC作为现场控制单元,以VC++6.0开发上位机程... 为实现液压退模系统中定程压制和定压压制两种工作模式,选择射流管型电液伺服阀驱动液压缸,利用电液伺服阀无级控制阀内开度的特性,结合位移和压力传感器,实现冲头行程和压力的反馈控制。采用PLC作为现场控制单元,以VC++6.0开发上位机程序,通过485总线通信实现对系统的远程监控。最终实现对压力机的位置控制与压力控制并可以实现位置控制精度在1 mm。 展开更多
关键词 电液伺服阀 液压退模 压力机系统 特种机械 串口通信 伺服控制 反馈控制 远程监控
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Fatigue behavior of basalt-aramid and basalt-carbon hybrid fiber reinforced polymer sheets 被引量:3
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作者 潘建伍 吴刚 袁希贵 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期84-87,共4页
In order to study the fatigue failure mode and fatigue life laws of basalt-aramid and basalt-carbon hybrid fiber reinforced polymer ( FRP ) sheets, fatigue experiments are carried out, considering two hybrid ratios ... In order to study the fatigue failure mode and fatigue life laws of basalt-aramid and basalt-carbon hybrid fiber reinforced polymer ( FRP ) sheets, fatigue experiments are carried out, considering two hybrid ratios of 1 : 1 and 2:1 under different stress levels from 0.6 to 0.95. The results show that fractures occur first in carbon fibers or aramid fibers for the specimens with hybrid ratio of 1: 1, namely B1A1 and B1C1, while a fracture occurs first in basalt fibers for the specimens with a hybrid ratio of 2: 1, namely B2A1 and B2C1. The fatigue lives of the hybrid FRP sheets increase with the improvement of the content of carbon fibers or aramid fibers, and the influence of the carbon fibers content improvement to fatigue life is more significant. The fatigue performance of B2A1 is relatively worse, while the fatigue performance of B1C1 and B2C1 is relatively better. Finally, a new fatigue stiffness degradation model with dual variables and double inflection points is presented, which is applicable to both hybrid and normal FRP sheets. 展开更多
关键词 hybrid fiber reinforced polymer sheet basalt-aramid basalt-carbon fatigue experiment stiffness degradation model
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SOI MOSFET Model Parameter Extraction via a Compound Genetic Algorithm 被引量:2
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作者 李瑞贞 李多力 +2 位作者 杜寰 海潮和 韩郑生 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第5期796-803,共8页
We improve the genetic algorithm by combining it with a simulated annealing algorithm. The improved algorithm is used to extract model parameters of SOI MOSFETs, which are fabricated with standard 1.2μm CMOS/SOI tech... We improve the genetic algorithm by combining it with a simulated annealing algorithm. The improved algorithm is used to extract model parameters of SOI MOSFETs, which are fabricated with standard 1.2μm CMOS/SOI technology developed by the Institute of Microelectronics of the Chinese Academy of Sciences. The simulation results using this model are in excellent agreement with experimental results. The precision is improved noticeably compared to commercial software. This method requires neither a deeper understanding of SOl MOSFETs model nor more complex computations than conventional algorithms used by commercial software. Comprehensive verification shows that this model is applicable to a very large range of device sizes. 展开更多
关键词 SOI parameter extraction genetic algorithm simulated annealing algorithm
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Path Planning Algorithm for Car-like Robot and Its Application 被引量:6
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作者 禹建丽 VALERIKroumov 成久洋之 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期98-104,共7页
The problem of path planning is studied for t he case for a mobile robot moving in a known environment. An aggressive algorith m using a description of the obstacles based on a neural network is proposed. Th e algorit... The problem of path planning is studied for t he case for a mobile robot moving in a known environment. An aggressive algorith m using a description of the obstacles based on a neural network is proposed. Th e algorithm allows to construct an optimal path which is piecewise linear with c hanging directions of the obstacles and the calculation speed for the proposed a lgorithm is comparatively fast. Simulation results and an application to a car_l ike robot 'Khepera' show the effectiveness of the proposed algorithm. 展开更多
关键词 path planning neural network pseudotemperatures
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OPTIMIZATION FOR COMBAT CONFIGURATION OF AIR DEFENSE WEAPON SYSTEMS 被引量:3
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作者 韩松臣 王兴贵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期48-52,共5页
At evaluating the combat effectiveness of the defense system, target′s probability to penetrate the defended area is a primary care taking index. In this paper, stochastic model to compete the probability that targe... At evaluating the combat effectiveness of the defense system, target′s probability to penetrate the defended area is a primary care taking index. In this paper, stochastic model to compete the probability that target penetrates the defended area along any flight path is established by the state analysis and statistical equilibrium analysis of stochastic service system theory. The simulated annealing algorithm is an enlightening random search method based on Monte Carlo recursion, and it can find global optimal solution by simulating annealing process. Combining stochastic model to compete the probability and simulated annealing algorithm, this paper establishes the method to solve problem quantitatively about combat configuration optimization of weapon systems. The calculated result shows that the perfect configuration for fire cells of the weapon is fast found by using this method, and this quantificational method for combat configuration is faster and more scientific than previous one based on principle via map fire field. 展开更多
关键词 air defense missile effectiveness analysis combat configuration simulated annealing algorithm stochastic service system
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Near-surface velocity model construction based on a Monte-Carlo scheme 被引量:2
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作者 杨锴 李辉 刘玉柱 《Applied Geophysics》 SCIE CSCD 2012年第4期475-482,497,共9页
In tomographic statics seismic data processing, it 1s crucial to cletermme an optimum base for a near-surface model. In this paper, we consider near-surface model base determination as a global optimum problem. Given ... In tomographic statics seismic data processing, it 1s crucial to cletermme an optimum base for a near-surface model. In this paper, we consider near-surface model base determination as a global optimum problem. Given information from uphole shooting and the first-arrival times from a surface seismic survey, we present a near-surface velocity model construction method based on a Monte-Carlo sampling scheme using a layered equivalent medium assumption. Compared with traditional least-squares first-arrival tomography, this scheme can delineate a clearer, weathering-layer base, resulting in a better implementation of damming correction. Examples using synthetic and field data are used to demonstrate the effectiveness of the proposed scheme. 展开更多
关键词 Monte Carlo sampling scheme construction of near-surface velocity model priorinformation poster probability distribution simulate annealing algorithm
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中继起爆具自动浇注装配线生产技术研究 被引量:2
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作者 卜令涛 咸会朵 +1 位作者 张真 王磊 《煤矿爆破》 2015年第1期15-18,共4页
为改变起爆具长期落后的生产局面,采用自动化、信息化技术设计开发了起爆具自动浇注装配生产线,研究了浇注次数、冒口以及半成品的冷却方式及时间对产品质量的影响,研制了高精度自动装药机、自动退模贴标一体机,实现了起爆具熔药、混药... 为改变起爆具长期落后的生产局面,采用自动化、信息化技术设计开发了起爆具自动浇注装配生产线,研究了浇注次数、冒口以及半成品的冷却方式及时间对产品质量的影响,研制了高精度自动装药机、自动退模贴标一体机,实现了起爆具熔药、混药、浇注、计量、壳体步进、冷却、退冒口、退模、去冒口药、清理、贴标等工序生产的连续化、自动化和智能化。 展开更多
关键词 起爆具 自动化 装药机 退模贴标一体机
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Unified Degradation Model in Low Gate Voltage Range During Hot-Carrier Stressing of p-MOS Transistors
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作者 胡靖 穆甫臣 +1 位作者 许铭真 谭长华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第2期124-130,共7页
Hot carrier effects of p MOSFETs with different oxide thicknesses are studied in low gate voltage range.All electrical parameters follow a power law relationship with stress time,but degradation slope is dependent ... Hot carrier effects of p MOSFETs with different oxide thicknesses are studied in low gate voltage range.All electrical parameters follow a power law relationship with stress time,but degradation slope is dependent on gate voltage.For the devices with thicker oxides,saturated drain current degradation has a close relationship with the product of gate current and electron fluence.For small dimensional devices,saturated drain current degradation has a close relationship with the electron fluence.This degradation model is valid for p MOSFETs with 0 25μm channel length and different gate oxide thicknesses. 展开更多
关键词 hot carrier effects p MOSFET degradation model electron fluence
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2D multi-scale hybrid optimization method for geophysical inversion and its application 被引量:2
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作者 潘纪顺 王新建 +4 位作者 张先康 徐朝繁 Zhao Ping 田晓峰 潘素珍 《Applied Geophysics》 SCIE CSCD 2009年第4期337-348,394,共13页
Local and global optimization methods are widely used in geophysical inversion but each has its own advantages and disadvantages. The combination of the two methods will make it possible to overcome their weaknesses. ... Local and global optimization methods are widely used in geophysical inversion but each has its own advantages and disadvantages. The combination of the two methods will make it possible to overcome their weaknesses. Based on the simulated annealing genetic algorithm (SAGA) and the simplex algorithm, an efficient and robust 2-D nonlinear method for seismic travel-time inversion is presented in this paper. First we do a global search over a large range by SAGA and then do a rapid local search using the simplex method. A multi-scale tomography method is adopted in order to reduce non-uniqueness. The velocity field is divided into different spatial scales and velocities at the grid nodes are taken as unknown parameters. The model is parameterized by a bi-cubic spline function. The finite-difference method is used to solve the forward problem while the hybrid method combining multi-scale SAGA and simplex algorithms is applied to the inverse problem. The algorithm has been applied to a numerical test and a travel-time perturbation test using an anomalous low-velocity body. For a practical example, it is used in the study of upper crustal velocity structure of the A'nyemaqen suture zone at the north-east edge of the Qinghai-Tibet Plateau. The model test and practical application both prove that the method is effective and robust. 展开更多
关键词 MULTI-SCALE seismic travel-time tomography hybrid optimization method INVERSION A'nyemaqen suture zone
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A SIMULATED ANNEALING METHOD FOR FAULT TREE ANALYSIS
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作者 刘子先 何桢 贾湖 《Transactions of Tianjin University》 EI CAS 1997年第2期113-116,共4页
This paper presents an approximate algorithm based on simulated annealing to achieve the maximum probability of the minimal cut sets for a fault tree. Near optimal minimal cut sets and important sequence of the basic ... This paper presents an approximate algorithm based on simulated annealing to achieve the maximum probability of the minimal cut sets for a fault tree. Near optimal minimal cut sets and important sequence of the basic events are also solved by the method. Computer simulations show that the algorithm performs very well. 展开更多
关键词 fault tree analysis minimal cut set simulated annealing probability of the minimal cut set
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A New Hybrid Method for Constrained Global Optimization
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作者 杨若黎 吴沧浦 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期16+7-16,共11页
By combining properly the simulated annealing algorithm and the nonlinear programming neural network, a new hybrid method for comtrained global optimization is proposed in this paper. To maintain the applicability of ... By combining properly the simulated annealing algorithm and the nonlinear programming neural network, a new hybrid method for comtrained global optimization is proposed in this paper. To maintain the applicability of the simulated annealing algorithm used in the hybrid method as general as possible, the nonlinear programming neural network is employed at each iteration to find only a feasible solution to the original constrained problem rather than a local optimal solution. Such a feasible solution is obtained by solving an auxiliary optimization problem with a new objective function. The computational results for two numerical examples indicate that the proposed hybrid method for constrained global optimization is not only highly reliable but also much more effcient than the simulated annealing algorithm using the penalty function method to deal with the constraints. 展开更多
关键词 OPTIMIZATION neural networks/global optimization simulated annealing
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Research on optimization of valve open time of the launch barge's ballast tanks
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作者 孙承猛 纪卓尚 《Journal of Marine Science and Application》 2009年第1期1-6,共6页
Launch barge is an effective tool for transporting ship segments from one place to another in shipyards. During shifting of segments onto a barge, the slideway on the barge's deck must be adjusted to maintain the sam... Launch barge is an effective tool for transporting ship segments from one place to another in shipyards. During shifting of segments onto a barge, the slideway on the barge's deck must be adjusted to maintain the same level as the wharf and also the barge must be kept level by adjusting the water in the ballast tanks. When to open the adjusting valves is an important factor influencing the barge's trim during the water-adjustment process. Because these adjustments are complex a mathematical model was formulated,after analyzing the characteristics of the process of moving the segments onto the barges deck, and considering the effects of this movement's speed and variations in tidal levels during the move. Then the model was solved by the penalty function method, the grid method, and improved simulated annealing, respectively. The best optimization model and its corresponding solution were then determined. Finally, it was proven that the model and the method adopted are correct and suitable, by calculating and analysing an example. 展开更多
关键词 launch barge STOWAGE penalty function method simulated annealing method grid method
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Novel hybrid optimal algorithm for broad-band Raman amplifier
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作者 常建华 肖韶荣 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期465-469,共5页
A hybrid optimal algorithm, named the SAA-PA in brief, based on the simulated annealing algorithm (SAA) and the Powell algorithm (PA) is proposed. The proposed algorithm puts the random search strategy of the SAA ... A hybrid optimal algorithm, named the SAA-PA in brief, based on the simulated annealing algorithm (SAA) and the Powell algorithm (PA) is proposed. The proposed algorithm puts the random search strategy of the SAA into the PA, which can prevent optimizing courses from trapping in local optima. The SAA-PA can effectively solve multimodal optimization in the distributed multi-pump Raman amplifier (DMRA). Optimal results show that, under the conditions of the on-off gain of 10 dB, the gain bandwidth of larger than 80 nm and the fiber length of 80 km, the gain ripple of less than 1.25 dB can be designed from the DMRA with only four backward pumps after the optimization of the proposed SAA-PA. Compared with the pure SAA, the SAA-PA can attain a lower gain ripple with the same number of pumps. Also, the relationship between the optimal signal bandwidth and the number of pumps can be simulated numerically with the SAA-PA. 展开更多
关键词 distributed multi-pump Raman amplifier simulated annealing algorithm Powell algorithm
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