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Bounded space algorithms for variant of variable-sized bin packing
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作者 李波 《Journal of Chongqing University》 CAS 2005年第3期164-169,共6页
Given a list of items and a sequence of variable-sized bins arriving one by one, it is NP-hard to pack the items into the bin list with a goal to minimize the total size of bins from the earliest one to the last used.... Given a list of items and a sequence of variable-sized bins arriving one by one, it is NP-hard to pack the items into the bin list with a goal to minimize the total size of bins from the earliest one to the last used. In this paper a set of approximation algorithms is presented for cases in which the ability to preview at most k(〉=2) arriving bins is given. With the essential assumption that all bin sizes are not less than the largest item size, analytical results show the asymptotic worst case ratios of all k-bounded space and offiine algorithms are 2. Based on experiments by applying algorithms to instances in which item sizes and bin sizes are drawn independently from the continuous uniform distribution respectively in the interval [0,u] and [u,l ], averagecase experimental results show that, with fixed k, algorithms with the Best Fit packing(closing) rule are statistically better than those with the First Fit packing(closing) rule. 展开更多
关键词 variable-sized bin packing bounded space algorithms offiine algorithms worst case performance average case performance
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An Improved Binary Wolf Pack Algorithm Based on Adaptive Step Length and Improved Update Strategy for 0-1 Knapsack Problems
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作者 Liting Guo Sanyang Liu 《国际计算机前沿大会会议论文集》 2017年第2期105-106,共2页
Binary wolf pack algorithm (BWPA) is a kind of intelligence algorithm which can solve combination optimization problems in discrete spaces.Based on BWPA, an improved binary wolf pack algorithm (AIBWPA) can be proposed... Binary wolf pack algorithm (BWPA) is a kind of intelligence algorithm which can solve combination optimization problems in discrete spaces.Based on BWPA, an improved binary wolf pack algorithm (AIBWPA) can be proposed by adopting adaptive step length and improved update strategy of wolf pack. AIBWPA is applied to 10 classic 0-1 knapsack problems and compared with BWPA, DPSO, which proves that AIBWPA has higher optimization accuracy and better computational robustness. AIBWPA makes the parameters simple, protects the population diversity and enhances the global convergence. 展开更多
关键词 binARY WOLF PACK algorithm 0-1 knapsack problem ADAPTIVE step length Update strategy
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Bin-Picking中无纹理工件的分割
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作者 刘瑶 赵慧 +1 位作者 伍世虔 陈彬 《机械设计与制造》 北大核心 2022年第9期278-281,287,共5页
为了解决Bin-Picking系统中无纹理工件的分割问题,提出了一种将颜色域和深度域信息融合的分割方法。该方法首先提取颜色域和深度域的边缘特征,然后基于二者的边缘特征,分别通过形态学预处理获取标记图,利用标记图辅助分水岭分割。融合... 为了解决Bin-Picking系统中无纹理工件的分割问题,提出了一种将颜色域和深度域信息融合的分割方法。该方法首先提取颜色域和深度域的边缘特征,然后基于二者的边缘特征,分别通过形态学预处理获取标记图,利用标记图辅助分水岭分割。融合二者的分割信息获得初分割结果,最后通过区域生长法以颜色域分割结果为边界优化分割区域。实验结果表明该算法适用于Bin-Picking视觉检测环节中无纹理目标的分割,对于复杂场景可获得较好的目标潜在位置区域,具有较高的鲁棒性和实时性。 展开更多
关键词 bin-Picking 无纹理工件 机器视觉 分水岭 目标分割
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BINSWANGER病颈动脉IMT与IGF-1相关性研究
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作者 田欢 刘晓平 红华 《内蒙古医学杂志》 2009年第11期1288-1290,共3页
目的:探讨Binswanger病颈动脉内膜-中层厚度(inti ma-media thickness,I MT)和血清胰岛素样生长因子-1(insulin 1ike growth factor-1,IGF-1)的相关性。方法:54例经临床确诊为Binswanger病(Binswanger’s disease BD)患者(经神经心理学... 目的:探讨Binswanger病颈动脉内膜-中层厚度(inti ma-media thickness,I MT)和血清胰岛素样生长因子-1(insulin 1ike growth factor-1,IGF-1)的相关性。方法:54例经临床确诊为Binswanger病(Binswanger’s disease BD)患者(经神经心理学检测分为3组:轻度痴呆22例、中度痴呆17例、重度痴呆15例)和30例门诊健康体检志愿者,用二维超声检测颈动脉内中膜厚度,同时测定静脉血胰岛素样生长因子-1(IGF-1)水平,并进行统计分析。结果:BD组血清IGF-I水平均明显低于健康对照组(P<0.05),轻度痴呆组和中度痴呆组差异有统计学意义(P<0.05),中度痴呆组和重度痴呆组比较有显著性差异(P<0.05)。血清IGF-I水平和颈动脉内膜-中层厚度呈中度负相关(r=-0.453),BD患者的颈动脉内膜-中层厚度均明显高于对照组(P<0.05),轻度痴呆组和中、重度痴呆组之间差异有统计学意义(P<0.05),中、重度痴呆组之间差异有统计学意义(P<0.05)。结论:血清IGF-1水平和颈动脉超声相结合,有助于BD痴呆程度的判断,为临床早期治疗BD提供可靠的依据。 展开更多
关键词 binS WANGER病 胰岛素样生长因子 颈动脉内膜-中层厚度
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Motion Planning System for Bin Picking Using 3-D Point Cloud 被引量:1
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作者 Masatoshi Hikizu Shu Mikami Hiroaki Seki 《Intelligent Control and Automation》 2016年第3期73-83,共12页
In this paper, we propose a motion planning system for bin picking using 3-D point cloud. The situation that the objects are put miscellaneously like the inside in a house is assumed. In the home, the equipment which ... In this paper, we propose a motion planning system for bin picking using 3-D point cloud. The situation that the objects are put miscellaneously like the inside in a house is assumed. In the home, the equipment which makes an object stand in line doesn’t exist. Therefore the motion planning system which considered a collision problem becomes important. In this paper, Information on the objects is measured by a laser range finder (LRF). The information is used as 3-D point cloud, and the objects are recognized by model-base. We propose search method of a grasping point for two-fingered robotic hand, and propose search method of a path to approach the grasping point without colliding with other objects. 展开更多
关键词 3-D Point Cloud bin Picking ICP algorithm Motion Planning
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Simple Insulin Dose Adjustment Using 3-3-1 Algorithm in Japanese Patients with Type 2 Diabetes: Start Kanazawa Study (Self-Titration Aggressive Algorithm with Glargine Trial) 被引量:1
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作者 Kenji D. Furukawa Naoto Yamaaki +2 位作者 Aya Fujimoto Kiminori Ohyama Hiroaki Muramoto 《Journal of Diabetes Mellitus》 2016年第3期197-203,共7页
We implemented a 3-3-1 algorithm in order to provide safe and simple self-titration in patients who newly initiated BOT as well as who were already on BOT and evaluated its utility in clinical setting. A total of 46 p... We implemented a 3-3-1 algorithm in order to provide safe and simple self-titration in patients who newly initiated BOT as well as who were already on BOT and evaluated its utility in clinical setting. A total of 46 patients, 21 patients in the newly-initiated group and 25 patients in the existing BOT group performed dose adjustment using 3-3-1 algorithm. HbA1c was significantly improved 4 weeks after the initiation from 8.5% ± 1.2% at baseline to 7.3% ± 0.7% at the final evaluation (p  0.01, vs. Baseline). The average daily insulin units increased throughout the study period from 10.1 ± 6.7 at baseline to 14.6 ± 8.9 units at the final evaluation. Weight didn’t significantly change throughout the study (p = 0.12). The incidents of hypoglycemia were 0.8/month during the insulin dose self-adjustment period and 0.4/month during the follow-up period. The 3-3-1 algorithm using insulin glargine provided a safe and simple dose adjustment and demonstrated its utility in patients who were newly introduced to insulin treatment as well as who were already on BOT. 展开更多
关键词 GLARGINE Self-Titration BOT T2DM INSULIN 3-3-1 algorithm
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Fast Multilevel CVT-Based Adaptive Data Visualization Algorithm
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作者 M.Emelianenko 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第2期195-211,共17页
Efficient data visualization techniques are critical for many scientific applications. Centroidal Voronoi tessellation(CVT) based algorithms offer a convenient vehicle for performing image analysis,segmentation and co... Efficient data visualization techniques are critical for many scientific applications. Centroidal Voronoi tessellation(CVT) based algorithms offer a convenient vehicle for performing image analysis,segmentation and compression while allowing to optimize retained image quality with respect to a given metric.In experimental science with data counts following Poisson distributions,several CVT-based data tessellation algorithms have been recently developed.Although they surpass their predecessors in robustness and quality of reconstructed data,time consumption remains to be an issue due to heavy utilization of the slowly converging Lloyd iteration.This paper discusses one possible approach to accelerating data visualization algorithms.It relies on a multidimensional generalization of the optimization based multilevel algorithm for the numerical computation of the CVTs introduced in[1],where a rigorous proof of its uniform convergence has been presented in 1-dimensional setting.The multidimensional implementation employs barycentric coordinate based interpolation and maximal independent set coarsening procedures.It is shown that when coupled with bin accretion algorithm accounting for the discrete nature of the data,the algorithm outperforms Lloyd-based schemes and preserves uniform convergence with respect to the problem size.Although numerical demonstrations provided are limited to spectroscopy data analysis,the method has a context-independent setup and can potentially deliver significant speedup to other scientific and engineering applications. 展开更多
关键词 Centroidal Voronoi tessellations computational algorithms Lloyd's method acceleration schemes multilevel method binning image analysis VISUALIZATION signal-to-noise ratio.
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A new integration algorithm for finite deformation of thermo-elasto-viscoplastic single crystals
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作者 Dan Zhao Yi-Guo Zhu +1 位作者 Ping Hu Wan-Xi Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期709-717,共9页
An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key fe... An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key feature of this new approach is that it can describe the finite deformation of crystals under thermal conditions. The obtained plastic deformation gradient contains not only plastic defor- mation but also thermal effects. The governing equation for the plastic deformation gradient is obtained based on ther- mal multiplicative decomposition of the total deformation gradient. An implicit method is used to integrate this evo- lution equation to ensure stability. Single crystal 1 100 aluminum is investigated to demonstrate practical applications of the model. The effects of anisotropic properties, time step, strain rate and temperature are calculated using this integration model. 展开更多
关键词 Integration algorithm - Thermal effect Anisotropic elasticity Single crystal Finite deformation
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An Algorithm of 0-1 Knapsack Problem Based on Economic Model
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作者 Yingying Tian Jianhui Lv Liang Zheng 《Journal of Applied Mathematics and Physics》 2013年第4期31-35,共5页
In order to optimize the knapsack problem further, this paper proposes an innovative model based on dynamic expectation efficiency, and establishes a new optimization algorithm of 0-1 knapsack problem after analysis a... In order to optimize the knapsack problem further, this paper proposes an innovative model based on dynamic expectation efficiency, and establishes a new optimization algorithm of 0-1 knapsack problem after analysis and research. Through analyzing the study of 30 groups of 0-1 knapsack problem from discrete coefficient of the data, we can find that dynamic expectation model can solve the following two types of knapsack problem. Compared to artificial glowworm swam algorithm, the convergence speed of this algorithm is ten times as fast as that of artificial glowworm swam algorithm, and the storage space of this algorithm is one quarter that of artificial glowworm swam algorithm. To sum up, it can be widely used in practical problems. 展开更多
关键词 0-1 KNAPSACK ECONOMIC Model Optimization algorithm STORAGE SPACE
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Relative efficiency appraisal of discrete choice modeling algorithms using small-scale maximum likelihood estimator through empirically tailored computing environment
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作者 Hyuk-Jae Roh Prasanta K. Sahu +1 位作者 Ata M. Khan Satish Sharma 《Journal of Modern Transportation》 2015年第1期67-79,共13页
Discrete choice models are widely used in multiple sectors such as transportation, health, energy, and marketing, etc., where the model estimation is usually carried out by using commercial software. Nonetheless, tail... Discrete choice models are widely used in multiple sectors such as transportation, health, energy, and marketing, etc., where the model estimation is usually carried out by using commercial software. Nonetheless, tailored computer codes offer modellers greater flexibility and control of unique modelling situation. Aligned with empirically tailored computing environment, this research discusses the relative performance of six different algorithms of a discrete choice model using three key performance measures: convergence time, number of iterations, and iteration time. The computer codes are developed by using Visual Basic Application (VBA). Maximum likelihood function (MLF) is formulated and the mathematical relationships of gradient and Hessian matrix are analytically derived to carry out the estimation process. The estimated parameter values clearly suggest that convergence criterion and initial guessing of parameters are the two critical factors in determining the overall estimation performance of a custom-built discrete choice model. 展开更多
关键词 Estimation algorithms - Visual basicapplication Convergence criterion binary logitMaximum likelihood
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Simulation Model Using Meta Heuristic Algorithms for Achieving Optimal Arrangement of Storage Bins in a Sawmill Yard
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作者 Asif Rahman Siril Yella Mark Dougherty 《Journal of Intelligent Learning Systems and Applications》 2014年第2期125-139,共15页
Bin planning (arrangements) is a key factor in the timber industry. Improper planning of the storage bins may lead to inefficient transportation of resources, which threaten the overall efficiency and thereby limit th... Bin planning (arrangements) is a key factor in the timber industry. Improper planning of the storage bins may lead to inefficient transportation of resources, which threaten the overall efficiency and thereby limit the profit margins of sawmills. To address this challenge, a simulation model has been developed. However, as numerous alternatives are available for arranging bins, simulating all possibilities will take an enormous amount of time and it is computationally infeasible. A discrete-event simulation model incorporating meta-heuristic algorithms has therefore been investigated in this study. Preliminary investigations indicate that the results achieved by GA based simulation model are promising and better than the other meta-heuristic algorithm. Further, a sensitivity analysis has been done on the GA based optimal arrangement which contributes to gaining insights and knowledge about the real system that ultimately leads to improved and enhanced efficiency in sawmill yards. It is expected that the results achieved in the work will support timber industries in making optimal decisions with respect to arrangement of storage bins in a sawmill yard. 展开更多
关键词 Simulation GENETIC algorithm Simulated ANNEALING Planning and Arrangement DECISION MAKING Storage bins LOG Stackers and Sawmill YARD
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THE FFD ALGORITHM FOR THE BIN PACKING PROBLEM WITH KERNEL ITEMS
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《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第3期97-102,共6页
THEFFDALGORITHMFORTHEBINPACKINGPROBLEMWITHKERNELITEMSZHANGGUOCHUANANDYAOENYUAbstract.TheFFDalgorithmisoneoft... THEFFDALGORITHMFORTHEBINPACKINGPROBLEMWITHKERNELITEMSZHANGGUOCHUANANDYAOENYUAbstract.TheFFDalgorithmisoneofthemostfamousalgor... 展开更多
关键词 FFD THE PACKING bin algorithm
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植物雌激素α-玉米赤霉醇对人正常乳腺的影响 被引量:6
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作者 邓文慧 吴宜勇 +3 位作者 段金虹 杨丽 王抒 戴顺龄 《中国医学科学院学报》 CAS CSCD 北大核心 2004年第5期566-570,共5页
目的研究植物雌激素α-玉米赤霉醇(α-ZAL)对人正常乳腺的影响。方法将人正常乳腺组织分别植入30只9~10周裸鼠体内,然后随机分为3组,每组10只,分别为:对照组(不给药)、α-ZAL1mg/kg组和5mg/kg组(于植入2~6周时隔日肌肉注射给药)。植入... 目的研究植物雌激素α-玉米赤霉醇(α-ZAL)对人正常乳腺的影响。方法将人正常乳腺组织分别植入30只9~10周裸鼠体内,然后随机分为3组,每组10只,分别为:对照组(不给药)、α-ZAL1mg/kg组和5mg/kg组(于植入2~6周时隔日肌肉注射给药)。植入6周后取出所有植入乳腺组织,采用免疫组织化学方法检测乳腺上皮细胞增殖细胞核抗原(PCNA)、抑凋亡基因Bcl-2、雌激素受体(ER)和孕激素受体(PR)的蛋白表达熏并观察给药前后植入组织块体积的改变和组织形态学特征;采用逆转录多聚酶链式反应(RT-PCR)方法检测雌激素硫酸转移酶(EST)mRNA和BIN1的表达水平。结果α-ZAL对植入乳腺上皮细胞的Bcl-2、PCNA、PR和ER蛋白表达及植入组织块体积的改变和组织形态学无明显影响。α-ZAL上调植入乳腺组织BIN1mRNA的表达,但对ESTmRNA表达无明显影响。结论α-ZAL对人正常乳腺的组织形态学和细胞增殖及凋亡特征无明显影响,但可增强肿瘤抑制蛋白BIN1mRNA的表达,提示对乳腺有潜在的保护作用。 展开更多
关键词 α-玉米赤霉醇乳腺 增殖 凋亡 ESTmRNA bin1mRNA
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Balls into bins分配器算法 被引量:1
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作者 李航 郭敬林 +1 位作者 刘西洋 陈平 《系统工程与电子技术》 EI CSCD 北大核心 2005年第1期115-116,共2页
针对传统的bitmap分配器算法中没有反馈机制,导致搜索不能很好地适应各种情况的问题。分析得到bitmap分配器算法中空闲块的搜索问题实际上是一个负载平衡的问题,因此将ballsintobins的负载平衡问题的研究结果应用在bitmap分配器上。将bi... 针对传统的bitmap分配器算法中没有反馈机制,导致搜索不能很好地适应各种情况的问题。分析得到bitmap分配器算法中空闲块的搜索问题实际上是一个负载平衡的问题,因此将ballsintobins的负载平衡问题的研究结果应用在bitmap分配器上。将bitmap分成不同的区,从中选出负载量小的区进行分析,经对比分析和对C3I系统的实际检验表明,这种分配器算法的确优于传统的bitmap分配器算法。 展开更多
关键词 BALLS into bins分配器 bitmap分配器 算法
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关于对称R-循环分块矩阵 被引量:6
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作者 何承源 《高校应用数学学报(A辑)》 CSCD 北大核心 1997年第3期353-360,共8页
给出了对称R-循环分块矩阵的概念,讨论了它的一些性质.当R=In时,得到了它的分解定理及标准形.
关键词 分解定理 标准形 循环矩阵 对称矩阵 分块矩阵
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联合SIFT特征点和CS-LBP特征描述子的复制粘贴篡改检测 被引量:6
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作者 刘丹 胡永健 刘琲贝 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第3期325-330,共6页
针对现有数字图像复制-粘贴篡改检测中尺度不变特征变换(Scale Invariant Feature Transform,简称SIFT)算法计算复杂度高的问题,文章提出一种将SIFT特征点和中心对称局部二进制模式(Center Symmet-ric-Local Binary Pattern,简称CS-LBP... 针对现有数字图像复制-粘贴篡改检测中尺度不变特征变换(Scale Invariant Feature Transform,简称SIFT)算法计算复杂度高的问题,文章提出一种将SIFT特征点和中心对称局部二进制模式(Center Symmet-ric-Local Binary Pattern,简称CS-LBP)描述子相结合的篡改检测方法。首先提取SIFT关键点,再对每个关键点生成CS-LBP特征描述子,并利用K-D(k-dimensional)树和BBF(Best-Bin-First)搜索算法寻找符合特征匹配关系的匹配点对,判断是否存在图像区域的篡改。实验表明,与同类算法相比,所提出算法在不损失检测精度的同时有效地减少了运算量。 展开更多
关键词 复制-粘贴篡改 尺度不变特征变换 中心对称局部二进制模式 特征匹配 BBF搜索算法
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k-箱限制在线装箱的一个注记
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作者 张国川 《曲阜师范大学学报(自然科学版)》 CAS 1996年第1期9-13,共5页
提出一个新的简单关闭规则 ,对算法进行改进 ,使相应的最差性能比在k≥ 3时均不超过 17/ 10 .
关键词 装箱 k-箱限制 在线算法 最佳化
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启发式探查最佳分割平面的快速KD-Tree构建方法 被引量:9
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作者 范文山 王斌 《计算机学报》 EI CSCD 北大核心 2009年第2期185-192,共8页
在基于光线跟踪方法的真实感绘制中,kd-tree是一种重要的加速结构.文章对kd-tree的构建方法进行了研究,提出了一种基于分区(binning)算法的快速构建方法.首先,通过分析kd-tree的成本函数,启发式地定位了当前节点的分割平面所在的子区间... 在基于光线跟踪方法的真实感绘制中,kd-tree是一种重要的加速结构.文章对kd-tree的构建方法进行了研究,提出了一种基于分区(binning)算法的快速构建方法.首先,通过分析kd-tree的成本函数,启发式地定位了当前节点的分割平面所在的子区间;其次,对探查到的子区间进行进一步的细化采样(sub-sampling),使得到的分割平面更好地逼近最优分割位置;同时,文章分析了现有方法在处理分割终止时存在的问题,提出了更加合理的分割终止条件.与以往方法相比,新方法用更小的计算成本生成了质量更好的kd-tree,构建过程更加鲁棒.实验数据验证了文中方法的有效性. 展开更多
关键词 光线跟踪 KD-TREE SAH 分区算法 细化采样
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Communication Resource Planning Algorithm Based on Time Triggered DIMA Architecture 被引量:1
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作者 Hongchun Wang Buqun Luan Wensheng Niu 《Journal of Beijing Institute of Technology》 EI CAS 2019年第2期327-335,共9页
Traditional scheduling algorithms for avionics communication have the shortcoming of messages accumulation,the efficiency and reliability of the service can be improved by combining the distributed integrated modular ... Traditional scheduling algorithms for avionics communication have the shortcoming of messages accumulation,the efficiency and reliability of the service can be improved by combining the distributed integrated modular avionics(DIMA)system with a time trigger mechanism.To further improve the utilization of system resources,the static scheduling algorithm of time triggered service is studied.By making the time trigger message schedule dispersedly,the stabilities of both the available time slots for the event triggered messages and the system will be improved.An improved two-dimensional bin packing algorithm is also presented to achieve the above-mentioned purpose with an extra benefit of better delay performance. 展开更多
关键词 distributed integrated MODULAR AVIONICS TIME-TRIGGERED two-dimensional bin PACKING algorithm
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A system-wide approach to minimize the operational cost of bench production in open-cast mining operations 被引量:5
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作者 Burak Ozdemir Mustafa Kumral 《International Journal of Coal Science & Technology》 EI 2019年第1期84-94,共11页
The production cycle of open-cast coal mines generally in eludes drilling, blasting, loading, hauling and coal preparation activities. Individual optimization of these activities does not mean that the whole system is... The production cycle of open-cast coal mines generally in eludes drilling, blasting, loading, hauling and coal preparation activities. Individual optimization of these activities does not mean that the whole system is optimized. This paper proposes a cost model considering all activities in mining cycle and system-wide approach to minimize the total mining cost of bench production. Since the fragmentation size and blast-hole diameter are linked to all activities of mining system, they are considered as decision variables in the problem form ul at io n. The operatio n costs are then minimized by using the evolutionary algorithm. Moreover, the impact of the change in the explosive price, and the hourly unit cost of equipment on total mining cost is quantified by sensitivity analysis. A case study is implemented to demonstrate the developed model. 展开更多
关键词 Mine PRODUCTION cycle Rock FRAGMENTATION - COST optimization EVOLUTIONARY algorithm Sensitivity analysis
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