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51.
Mehdi Ghatee S. Mehdi Hashemi Behnam Hashemi Mehdi Dehghan 《Computers & Mathematics with Applications》2008,55(12):2767-2790
Duality properties have been investigated by many researchers in the recent literature. They are introduced in this paper for a fully fuzzified version of the minimal cost flow problem, which is a basic model in network flow theory. This model illustrates the least cost of the shipment of a commodity through a capacitated network in terms of the imprecisely known available supplies at certain nodes which should be transmitted to fulfil uncertain demands at other nodes. First, we review on the most valuable results on fuzzy duality concepts to facilitate the discussion of this paper. By applying Hukuhara’s difference, approximated and exact multiplication and Wu’s scalar production, we exhibit the flow in network models. Then, we use combinatorial algorithms on a reduced problem which is derived from fully fuzzified MCFP to acquire fuzzy optimal flows. To give duality theorems, we utilize a total order on fuzzy numbers due to the level of risk and realize optimality conditions for providing some efficient combinatorial algorithms. Finally, we compare our results with the previous worthwhile works to demonstrate the efficiency and power of our scheme and the reasonability of our solutions in actual decision-making problems. 相似文献
52.
为掌握主缆初应力对桥梁动力特性的影响,以悬索桥为例,采用静力非线性分析方法计算应力变化过程中悬索桥的跨中挠度、缆索轴力及加劲梁的轴力变化;将得到的内力作为结构的预加应力进行有预应力的模态分析. 应用ANSYS软件进行分析,其中有限元建模时采用4种单元类型:空间梁单元BEAM4用于模拟加劲梁和塔;空间杆单元LINK10用于模拟主缆及吊杆;通过设定BEAM4和LINK10单元初应变进行有预应力的模态分析;采用MASS21单元模拟横隔板、吊杆锚固装置和桥面上的栏杆,并分别考虑质量和质量惯性矩的作用. 分析表明,悬索桥主梁竖弯振动频率受主缆初应力的影响较大,而侧弯振动频率和扭转振动频率受此影响较小. 该结果为同类桥梁的动力特性分析提供参考. 相似文献
53.
矢量量化(VQ)是一种高效的有损压缩技术。快速码字搜索算法是矢量量化的核心问题之一,其性能决定了编码时间。快速码字搜索算法中,绝对误差不等式删除算法(AEI)是一种典型的3步算法,其第1步查找输入矢量的初始匹配码字的方法采用了Minimax法,是整个AEI算法中计算量最大的步骤,严重影响了算法的效率。针对这个问题,提出了一种新的查找初始匹配码字的方法——Partial Minimax法。该方法在保证所找到的初始匹配码字与原始AEI算法相同并且重建图像的PSNR(峰值信噪比)值不变的前提下,可显著减小这一步骤的计算量和查找时间,从而有效地提高了算法的总体编码速度。 相似文献
54.
维吾尔语词首音节元音声学分析 总被引:1,自引:0,他引:1
该文利用“维吾尔语语音声学参数数据库”,统计分析和归纳了维吾尔语词首音节元音的共振峰模式及其分布格局。声学元音图有多种画法,该文采用JOOS型声学元音图。这种元音图的特点是以F1为纵坐标,以F2为横坐标。这样绘制成的声学元音图与元音舌位图有很好的对应性。维语标准音词首音节中有[y, i, e, O, u, o, ;, A]等8个元音。舌位前后的分布特点是[u, o, A]为后元音,[y, i, e, O, ;]为前元音;开口度(舌位高低)分布特点是[y, i, u]为高元音,[e, O, o]为次高元音,[;]为次低元音, [A]为低元音. 相似文献
55.
Yuko Kizu Ray Hasegawa Isao Amemiya Shuichi Uchikoga Hirofumi Wakemoto 《Journal of the Society for Information Display》2009,17(8):647-658
Abstract— A 9‐in. full‐color polymer‐stabilized OCB TFT‐LCD with stable bend alignment in the absence of an electric field was developed. The condition of the polymer stabilization, the characteristics of UV‐curable monomers, and their influence on the configurations of the polymer network in the cell were studied. Possible models of the configuration were proposed and their relationship to the electro‐optical properties was analyzed using a novel simulation method considering the distribution of anchoring effects from both alignment surfaces and the polymer network. It was suggested that a good performance such as high contrast ratio and fast response could be expected in the polymer network originating from newly developed monomers composed of multifunctional LC acrylates due to a relatively weak‐anchoring effect and presumably its localization near the alignment surfaces. By using the newly developed monomers under the optimized polymer‐stabilizing process, a high contrast ratio of 250:1 and fast response nearly equal to that of a conventional OCB cell were achieved. 相似文献
56.
Anti-reflective (AR) boundary conditions (BC) have been introduced recently in connection with fast deblurring algorithms,
both in the case of signals and images. Here we extend such BCs to d dimensions (d ≥ 1) and we study in detail the algebra induced by the AR-BCs, with strongly symmetric point spread functions (PSF), both
from a structural and computational point of view. The use of the re-blurring idea and the computational features of the AR-algebra
allow us to apply Tikhonov-like techniques within O(n
d
log(n)) arithmetic operations, where n
d
is the number of pixels of the reconstructed object. Extensive numerical experimentation concerning 2D images and strongly
symmetric PSFs confirms the effectiveness of our proposal.
相似文献
57.
为解决虚拟加工中工件毛坯模型的识别问题,提出对规则形状工件毛坯采用OpenGL建模、对复杂形状工件毛坯采用美国初始图形交换规范(Initial Graphics Exchange Specification,IGES)文件进行模型数据转换的方法.该方法利用CAD软件为工件毛坯进行三维造型,生成IGES文件,然后在虚拟加工环境下读取IGES文件并生成工件毛坯模型,从而实现工件毛坯模型在新环境中的建立.经过建立具体的工件毛坯模型,验证相关理论的正确性,为在虚拟加工环境下工件毛坯模型的建立提供可行的依据. 相似文献
58.
《Displays》2023
An adaptive local backlight dimming algorithm is proposed considering human visual sensitivities under various viewing conditions. Local dimming amount is maximized based on contrast sensitivity function and local image characteristics to minimize perceived luminance and contrast losses maintaining image qualities. Average luminance, contrast and spatial frequency are evaluated as local image characteristics. As dimming based on local characteristics has blocking artifacts, a compensation method using edge luminance difference is proposed considering human responses. The proposed algorithms reduce backlight power consumption by 39.69% on average, with an average SSIM of 0.995. It can be increased by 5.66% with varying viewing conditions, resulting in a 45.35% power consumption reduction on average. The outperformances of the proposed algorithm in power consumption reduction and maintaining image quality are verified with various image quality metrics compared to recent dimming algorithms. 相似文献
59.
Yongchao Liu Wuwenqing Yan Shengchao Zhao 《International Transactions in Operational Research》2022,29(1):48-62
Two-stage stochastic linear complementarity problems (TSLCP) model a large class of equilibrium problems subject to data uncertainty, and are closely related to two-stage stochastic optimization problems. The sample average approximation (SAA) method is one of the basic approaches for solving TSLCP and the consistency of the SAA solutions has been well studied. This paper focuses on building confidence regions of the solution to TSLCP when SAA is implemented. We first establish the error-bound condition of TSLCP and then build the asymptotic and nonasymptotic confidence regions of the solutions to TSLCP by error-bound approach, which is to combine the error-bound condition with central limit theory, empirical likelihood theory, and large deviation theory. 相似文献
60.
采用IEC脉冲电流法(IEC60270标准)对液氮温区超导复合绝缘沿面放电现象及其影响因素进行了研究。在六面屏蔽的局部放电实验室内,研究了不同放电条件对放电起始电压、放电量、击穿电压等的影响,进而研究了其作用机理,并用有限元方法开展了相关计算。实验数据表明,不同放电条件明显影响放电重复率、平均放电量、最大放电量等,放电产生的气泡越容易逸出,放电越严重;液氮的流动使放电起始电压有一定的升高,但对最终击穿电压影响不大;在放电通道上施加阻挡之后可明显提高最终的闪络击穿电压。 相似文献