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Stress initialization methods for dynamic numerical simulation of rock mass with high in-situ stress 被引量:31
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作者 YANG Jia-cai LIU Ke-wei +1 位作者 LI Xu-dong LIU Zhi-xiang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期3149-3162,共14页
In the context of deep rock engineering,the in-situ stress state is of major importance as it plays an important role in rock dynamic response behavior.Thus,stress initialization becomes crucial and is the first step ... In the context of deep rock engineering,the in-situ stress state is of major importance as it plays an important role in rock dynamic response behavior.Thus,stress initialization becomes crucial and is the first step for the dynamic response simulation of rock mass in a high in-situ stress field.In this paper,stress initialization methods,including their principles and operating procedures for reproducing steady in-situ stress state in LS-DYNA,are first introduced.Then the most popular four methods,i.e.,explicit dynamic relaxation(DR)method,implicit-explicit sequence method,Dynain file method and quasi-static method,are exemplified through a case analysis by using the RHT and plastic hardening rock material models to simulate rock blasting under in-situ stress condition.Based on the simulations,it is concluded that the stress initialization results obtained by implicit-explicit sequence method and dynain file method are closely related to the rock material model,and the explicit DR method has an obvious advantage in solution time when compared to other methods.Besides that,it is recommended to adopt two separate analyses for the whole numerical simulation of rock mass under the combined action of in-situ stress and dynamic disturbance. 展开更多
关键词 in-situ stress stress initialization method dynamic disturbance numerical simulation rock mass
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Particle filter initialization in non-linear non-Gaussian radar target tracking 被引量:3
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作者 Wang Jian Jin Yonggao +2 位作者 Dai Dingzhang Dong Huachun Quan Taifan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期491-496,共6页
When particle filter is applied in radar target tracking, the accuracy of the initial particles greatly effects the results of filtering. For acquiring more accurate initial particles, a new method called “competitio... When particle filter is applied in radar target tracking, the accuracy of the initial particles greatly effects the results of filtering. For acquiring more accurate initial particles, a new method called “competition strategy algorithm” is presented. In this method, initial measurements give birth to several particle groups around them, regularly. Each of the groups is tested several times, separately, in the beginning periods, and the group that has the most number of efficient particles is selected as the initial particles. For this method, sample initial particles selected are on the basis of several measurements instead of only one first measurement, which surely improves the accuracy of initial particles. The method sacrifices initialization time and computation cost for accuracy of initial particles. Results of simulation show that it greatly improves the accuracy of initial particles, which makes the effect of filtering much better. 展开更多
关键词 radar target tracking particle filter initialization.
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Evolution of the volume expansion of SiO/C composite electrodes in lithium-ion batteries during aging cycles
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作者 Haosong Yang Kai Sun +2 位作者 Xueyan Li Peng Tan Lili Gong 《中国科学技术大学学报》 北大核心 2025年第2期27-33,26,I0001,共9页
As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation ... As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries. 展开更多
关键词 lithium-ion batteries in situ expansion measurement initial stress cycle life SiO/C composite electrode
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Numerical study on flow characteristics of large copper smelting bottom-blown furnace under strong and weak coupling oxygen supply
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作者 JIANG Bao-cheng GUO Xue-yi +1 位作者 WANG Song-song WANG Qin-meng 《Journal of Central South University》 2025年第2期363-375,共13页
The melt stirring in a large copper smelting oxygen bottom-blown furnace is caused by the large amount of gas movement blown in by two rows of oxygen lances.At present,the two rows of oxygen lances provide oxygen of e... The melt stirring in a large copper smelting oxygen bottom-blown furnace is caused by the large amount of gas movement blown in by two rows of oxygen lances.At present,the two rows of oxygen lances provide oxygen of equal strength,and the stirring in the central area of the melt is insufficient,which restricts the efficient progress of the smelting reaction.This study proposes a strong-weak coupling oxygen supply method and establishes an equivalent model based on a large bottom-blown furnace(LBBF)of an enterprise to simulate the bubble characteristics and flow characteristics of the molten pool.The results show that adjusting the flow ratio between the two rows of oxygen lances can create a“strong”and a“weak”coexisting source of disturbance in an LBBF.It is worth noting that when the flow rate ratio of the two rows of oxygen lances is 1.6,the peak velocity generated by the“strong”distur bance source in the molten pool increases by 18.92%,and the disturbance range increases.This method effectively strengthens the stirring in the central area of the molten pool,improves smelting efficiency,and does not produce harmful melt splashes.It provides important guidance for optimizing production practice. 展开更多
关键词 large bottom-blown furnace oxygen supply flow characteristics initial bubbles
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Study on the characteristics of crack initiation in deep dense shale containing circular hole under varying stress conditions
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作者 XIE Hong-qiang FENG Gan +4 位作者 LIU Huai-zhong HE Qiang XIAO Ming-li PEI Jian-liang TAHERDANGKOO Reza 《Journal of Central South University》 2025年第1期244-261,共18页
The evolution of cracks in shale directly affects the efficient production of shale gas.However,there is a lack of research on the characteristics of crack initiation in deep dense shale under different stress conditi... The evolution of cracks in shale directly affects the efficient production of shale gas.However,there is a lack of research on the characteristics of crack initiation in deep dense shale under different stress conditions.In this work,considering the different combinations of confining pressure and bedding plane inclination angle(α),biaxial mechanical loading experiments were conducted on shale containing circular holes.The research results indicate that the confining pressure and inclination angle of the bedding planes significantly influence the failure patterns of shale containing circular holes.The instability of shale containing circular holes can be classified into five types:tensile failure along the bedding planes,tensile failure through the bedding planes,shear slip along the bedding planes,shear failure through the bedding planes,and block instability failure.Furthermore,the evolution of strain and stress fields around the circular holes was found to be the fundamental cause of variations in the initiation characteristics and locations of shale cracks.The crack initiation criterion for shale containing circular hole was established,providing a new method for evaluating the trajectory of shale hole wall fractures.This study holds significant importance for evaluating the evolution and stability of fracture networks within shale reservoirs. 展开更多
关键词 shale gas deep dense shale crack initiate characteristics failure modes
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Undrained cyclic simple shear characteristics of transparent sand manufactured by fused quartz
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作者 ZHAO Jin-qiao OU Qiang +4 位作者 JIANG Chun-yong DING Xuan-ming ZHOU Hang YANG Chang-wei DENG Wei-ting 《Journal of Central South University》 2025年第9期3427-3446,共20页
Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear ... Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear tests were conducted on the saturated transparent sand composed of fused quartz and refractive index-matched oil mixture. The results reveal that an increase in the initial shear stress ratio significantly affects the shape of the hysteresis loop, particularly resulting in more pronounced asymmetrical accumulation. Factors such as lower relative density, higher cyclic stress ratios and higher initial shear stress ratio have been shown to accelerate cyclic deformation, cyclic pore water pressure and stiffness degradation. The cyclic liquefaction resistance curves decrease as the initial shear stress ratio increases or as relative density decreases. Booker model and power law function model were applied to predict the pore water pressure for transparent sand. Both models yielded excellent fits for their respective condition, indicating a similar dynamic liquefaction pattern to that of natural sands. Finally, transparent sand displays similar dynamic characteristics in terms of cyclic liquefaction resistance and Kα correction factor. These comparisons indicate that transparent sand can serve as an effective means to mimic many natural sands in dynamic model tests. 展开更多
关键词 transparent sand fused quartz undrained cyclic simple shear tests dynamic characteristics initial shear stress
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Optimized joint repair effects on damage evolution and arching mechanism of CRTS II slab track under extreme thermal conditions
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作者 CAI Xiao-pei CHEN Ze-lin +3 位作者 CHEN Bo-jing ZHONG Yang-long ZHOU Rui HUANG Yi-chen 《Journal of Central South University》 2025年第6期2273-2287,共15页
To address the issue of extreme thermal-induced arching in CRTS II slab tracks due to joint damage,an optimized joint repair model was proposed.First,the formula for calculating the safe temperature rise of the track ... To address the issue of extreme thermal-induced arching in CRTS II slab tracks due to joint damage,an optimized joint repair model was proposed.First,the formula for calculating the safe temperature rise of the track was derived based on the principle of stationary potential energy.Considering interlayer evolution and structural crack propagation,an optimized joint repair model for the track was established and validated.Subsequently,the impact of joint repair on track damage and arch stability under extreme temperatures was studied,and a comprehensive evaluation of the feasibility of joint repair and the evolution of damage after repair was conducted.The results show that after the joint repair,the temperature rise of the initial damage of the track structure can be increased by 11℃.Under the most unfavorable heating load with a superimposed temperature gradient,the maximum stiffness degradation index SDEG in the track structure is reduced by about 81.16%following joint repair.The joint repair process could effectively reduce the deformation of the slab arching under high temperatures,resulting in a reduction of 93.96%in upward arching deformation.After repair,with the damage to interfacing shear strength,the track arch increases by 2.616 mm. 展开更多
关键词 CRTS II slab track optimized joint repair arching mechanism temperature load damage initiation and evolution
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心肾综合征发病机制和治疗新进展 被引量:12
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作者 余云华 沈明 +1 位作者 李然 郑兴 《实用医学杂志》 CAS 北大核心 2016年第2期169-171,共3页
心肾综合征(cardiorenal syndrome,CRS)主要指心脏衰竭导致肾脏损害的病变。在过去的10年,心肾的相互作用得到密切的关注;CRS的定义也随时间的推移而逐步发展和完善。2010年改善全球肾脏病预后(kidney disease:improving global out... 心肾综合征(cardiorenal syndrome,CRS)主要指心脏衰竭导致肾脏损害的病变。在过去的10年,心肾的相互作用得到密切的关注;CRS的定义也随时间的推移而逐步发展和完善。2010年改善全球肾脏病预后(kidney disease:improving global outcomes,KDIGO)和急性透析质量指导组(acute dialysis quality initiative group,ADQI)发表专家共识,明确地将CRS定义为:心脏和肾脏其中一个器官的急性或慢性功能障碍可能导致另一器官的急性或慢性功能损害的临床综合征。 展开更多
关键词 心肾综合征 心脏衰竭 透析质量 DIALYSIS 肾脏功能 治疗新进展 肾功能不全 发病机制 initiative 射血分数
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提升等离子体初始密度抑制逃逸电子的实验研究 被引量:3
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作者 竹锦霞 段卓琦 +3 位作者 巨洪军 蔡武德 朱俊 陈忠勇 《核聚变与等离子体物理》 CAS CSCD 北大核心 2010年第4期332-334,共3页
利用硬X射线诊断监测逃逸电子,研究了HT-7装置放电初始阶段不同等离子体初始密度对逃逸电子产生过程的影响。实验结果表明,提高等离子体初始密度能有效地抑制逃逸电子的产生。
关键词 等离子体 初始密度 抑制 逃逸电子 实验研究 PLASMA DENSITY INITIAL 实验结果 初始阶段 产生过程 装置 诊断 射线 监测 放电 HT-7
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云南潞西三台山超镁铁岩体Os-Nd-Pb-Sr同位素特征及地质意义 被引量:12
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作者 储著银 王伟 +3 位作者 陈福坤 王秀丽 李向辉 季建清 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3221-3228,共8页
滇西地区特提斯造山带具有多块体拼合的构造特点,是东特提斯造山带的重要组成部分之一,其大地构造演化对理解全球特提斯造山带具有重要的地质意义。在腾冲和保山地块之间的龙陵-瑞丽断裂带中出露超镁铁质岩石,曾被解释为两个陆块缝合的... 滇西地区特提斯造山带具有多块体拼合的构造特点,是东特提斯造山带的重要组成部分之一,其大地构造演化对理解全球特提斯造山带具有重要的地质意义。在腾冲和保山地块之间的龙陵-瑞丽断裂带中出露超镁铁质岩石,曾被解释为两个陆块缝合的证据。本文采用高灵敏度高精度超低本底Re-Os、Sm-Nd、Pb和Rb-Sr同位素分析技术,对采自该断裂带潞西三台山的超镁铁岩样品进行了Os-Nd-Pb-Sr同位素测定。分析结果表明,这些超镁铁岩石具有强烈富集特征。分析的5个岩石样品具有高的初始^(87)Sr/^(86)Sr值(0.71074~0.71444)、低的初始ε_(Nd)值(-6.2~-10.6)、低初始γ_(Os)值(-4.8~-8.8)和较高的初始铅同位素比值,其Os同位素模式年龄值(t_(RD))为0.97~1.71Ga。Nd-Os同位素组成特征表明,三台山超镁铁岩具有古老的富集大陆岩石圈地幔岩石的特征,不能作为腾冲和保山地块的缝合证据。 展开更多
关键词 云南潞西 超镁铁岩体 同位素特征 地质意义 western Yunnan initial isotopic characteristics 大陆岩石圈地幔 lithospheric mantle 造山带 特提斯 tectonic evolution 同位素分析技术 high precision understanding 铅同位素比值 断裂带 大地构造演化 超镁铁质岩石 同位素组成
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食蟹猴疟原虫 (Plasmodium cynomolgi)中一个真核翻译起始因子4A(eIF-4A)同源蛋白的cDNA克隆、表达和ATP酶活性测定(英文) 被引量:4
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作者 宋平 张竞男 +1 位作者 胡珈瑞 李奎 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2004年第3期294-304,共11页
真核翻译起始因子 4A(eukaryoticinitiationfactor 4A ,eIF 4A)是DEAD盒蛋白家族的ATP依赖性的RNA解旋酶类中的一个原型成员 .它在真核细胞的蛋白质合成的起始过程中起着关键性作用 .通过PCR扩增和放射探针杂交相结合的方法筛选食蟹猴... 真核翻译起始因子 4A(eukaryoticinitiationfactor 4A ,eIF 4A)是DEAD盒蛋白家族的ATP依赖性的RNA解旋酶类中的一个原型成员 .它在真核细胞的蛋白质合成的起始过程中起着关键性作用 .通过PCR扩增和放射探针杂交相结合的方法筛选食蟹猴疟原虫 (Plasmodiumcynomolgi)的cDNA文库 ,克隆了一个eIF 4A同源蛋白的完整cDNA序列 ,命名为CH1F .CH1F全长 1 75 3bp ,包含一个1 1 97bp的完整阅读框 ,推测编码一个由 398个氨基酸组成的蛋白 .对CH1F的蛋白序列用BlastP进行搜索和分析 ,提示它应该是DEAD盒家族的一个eIF 4A同源蛋白 ;用DNAStar将其与许多典型的DEAD盒蛋白序列进行比对分析 ,结果显示 :比起其它的DEAD盒蛋白 ,它与eIF 4A或eIF 4A的同源蛋白具有更高的同源性和更多序列上的相似结构域 .将包含完整阅读框的片段亚克隆进表达载体pET 2 8a (+) ,在大肠杆菌DH5α中表达 ,产生的融合蛋白大小在 4 5kD左右 .对该融合蛋白进行纯化、重新折叠和初步鉴定 .ATP酶活性检测显示 ,该融合蛋白只有很低的ATP酶活性 ,而且它的ATP酶活性似乎不依赖于核酸底物 .对这一检测结果给出 3种可能的原因 .这一检测结果与根据序列分析得到的推论———CH1F蛋白可能是一个eIF 展开更多
关键词 真核翻译起始因子4A(eukaryotic initiation factor 4A eIF-4A) RNA解旋酶 ATP酶 食蟹猴 疟原虫(Plasmodium cynomolgi)
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iSCSI Target的设计与实现 被引量:1
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作者 曾东 周敬利 +1 位作者 余胜生 朱建峰 《小型微型计算机系统》 CSCD 北大核心 2005年第4期582-584,共3页
iSCSI技术正被越来越多的系统、存储设备和网络厂商所采用.在Linux环境下,设计并实现了一种iSCSITarget,从设备发现、基于WEB的配置与管理、用户身份认证以及功能实现与性能测试等方面做了较详细探讨.
关键词 ISCSI INITIATOR ISCSI TARGET
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优化背景值的GM(1,1) 被引量:1
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作者 王换鹏 刘文 +2 位作者 单锐 张雁 靳飞 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2012年第2期264-267,共4页
为了提高模型的拟合精度,提出了一种新的改进GM(1,1)模型.从优化GM(1,1)模型背景值的定义出发,推导出利用原始数据生成的背景值公式,将其与经过优化的初始条件结合,构造出改进的GM(1,1)模型.此模型将在很大程度上消除由于背景值的选取... 为了提高模型的拟合精度,提出了一种新的改进GM(1,1)模型.从优化GM(1,1)模型背景值的定义出发,推导出利用原始数据生成的背景值公式,将其与经过优化的初始条件结合,构造出改进的GM(1,1)模型.此模型将在很大程度上消除由于背景值的选取所产生的误差.对该模型进行数据模拟,通过与原模型中数据的比较、分析,验证出新的优化模型具有更好的模拟精度,说明该模型的有效性,可以将其应用于对其它数据的拟合预测. 展开更多
关键词 GREY system theory GM (1 1) model initial condition BACKGROUND VALUE optimize reduced VALUE time response sequence simulation precision
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PSO算法结合BP神经网络在传感器静态非线性校正中的应用 被引量:5
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作者 张媛媛 徐科军 +2 位作者 许耀华 黄胜初 Yuan-yuan Ke-jun Yao-hua Sheng-chu 《计量学报》 CSCD 北大核心 2009年第6期-,共4页
将粒子群优化(PSO)算法与BP神经网络相结合,应用在传感器静态非线性特性的校正中.用PSO算法所得到的全局最优值作为BP神经网络的初始权值,训练BP神经网络,训练结束后的神经网络作为传感器的静态特性校正器.应用结果表明,该方法可以提高B... 将粒子群优化(PSO)算法与BP神经网络相结合,应用在传感器静态非线性特性的校正中.用PSO算法所得到的全局最优值作为BP神经网络的初始权值,训练BP神经网络,训练结束后的神经网络作为传感器的静态特性校正器.应用结果表明,该方法可以提高BP神经网络的精度,并且该神经网络具有良好的泛化能力. Abstract: A static nonlinear errors method for correcting the sensors based on BP neural network using particle swarm optimization (PSO) is described. The global best values of particle swarm are used as initial weights of BP neural network to train BP neural network. Then the trained neural network is regarded as the sensor's corrector. The application results show that this method can improve the precision of the BP neural network, and the generalization capability of the neural network is good. 展开更多
关键词 PSO算法 神经网络 传感器 非线性校正 BP NEURAL NETWORK BP NEURAL NETWORK particle swarm optimization generalization capability application results 全局最优值 粒子群优化 非线性特性 应用结果 训练 静态特性 泛化能力 初始权值 initial improve 校正器
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Experiment study of optimization on prediction index gases of coal spontaneous combustion 被引量:5
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作者 NIU Hui-yong 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2321-2328,共8页
The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory d... The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory determination were initialized for the value which was defined as "K". The ratio of each index gas and value of "K", and the ratio of combination index gases and value of "K", were analyzed simultaneously. The research results show that for this coal mine, if there is carbon monoxide in the gas sample, the phenomenon of oxidation and temperature rising for coal exists in this mine; if there is C_2H_4 in the gas sample, the temperature of coal perhaps exceeds 130 °C. If the coal temperature is between 35 °C and 130 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(CO)/K mainly; if the temperature of coal is between 130 °C and 300 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(C_2H_6)/Φ(C_2H_2) and Φ(C_2H_6)/K. The research results provide experimental basis for the prediction of coal spontaneous combustion in Anyuan coal mine, and have better guidance on safe production of this coal mine. 展开更多
关键词 COAL spontaneous combustion index gases PREDICTION initialization
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Artificial bee colony algorithm with comprehensive search mechanism for numerical optimization 被引量:5
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作者 Mudong Li Hui Zhao +1 位作者 Xingwei Weng Hanqiao Huang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期603-617,共15页
The artificial bee colony (ABC) algorithm is a sim- ple and effective global optimization algorithm which has been successfully applied in practical optimization problems of various fields. However, the algorithm is... The artificial bee colony (ABC) algorithm is a sim- ple and effective global optimization algorithm which has been successfully applied in practical optimization problems of various fields. However, the algorithm is still insufficient in balancing ex- ploration and exploitation. To solve this problem, we put forward an improved algorithm with a comprehensive search mechanism. The search mechanism contains three main strategies. Firstly, the heuristic Gaussian search strategy composed of three different search equations is proposed for the employed bees, which fully utilizes and balances the exploration and exploitation of the three different search equations by introducing the selectivity probability P,. Secondly, in order to improve the search accuracy, we propose the Gbest-guided neighborhood search strategy for onlooker bees to improve the exploitation performance of ABC. Thirdly, the self- adaptive population perturbation strategy for the current colony is used by random perturbation or Gaussian perturbation to en- hance the diversity of the population. In addition, to improve the quality of the initial population, we introduce the chaotic opposition- based learning method for initialization. The experimental results and Wilcoxon signed ranks test based on 27 benchmark func- tions show that the proposed algorithm, especially for solving high dimensional and complex function optimization problems, has a higher convergence speed and search precision than ABC and three other current ABC-based algorithms. 展开更多
关键词 artificial bee colony (ABC) function optimization search strategy population initialization Wilcoxon signed ranks test.
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iSCSI Initiator的实现概要 被引量:1
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作者 路海 李立清 《计算机应用》 CSCD 北大核心 2003年第z2期239-241,共3页
iSCSI已成为SAN中重要的协议。文中分析了iSCSIInitiator在操作系统中的层次框架 ,并简述了一种实现方案。
关键词 ISCSI ISCSI INITIATOR 实现 设备驱动
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State estimation in range coordinate using range-only measurements 被引量:3
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作者 LI Keyi GUO Zhengkun ZHOU Gongjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第3期497-510,共14页
In some tracking applications,due to the sensor characteristic,only range measurements are available.If this is the case,due to the lack of full position measurements,the observability of Cartesian states(e.g.,positio... In some tracking applications,due to the sensor characteristic,only range measurements are available.If this is the case,due to the lack of full position measurements,the observability of Cartesian states(e.g.,position and velocity)are limited to particular cases.For general cases,the range measurements can be utilized by developing a state estimation algorithm in range-Doppler(R-D)plane to obtain accurate range and Doppler estimates.In this paper,a state estimation method based on the proper dynamic model in the R-D plane is proposed.The unscented Kalman filter is employed to handle the strong nonlinearity in the dynamic model.Two filtering initialization methods are derived to extract the initial state estimate and the initial covariance in the R-D plane from the first several range measurements.One is derived based on the well-known two-point differencing method.The other incorporates the correct dynamic model information and uses the unscented transformation method to obtain the initial state estimates and covariance,resulting in a model-based method,which capitalizes the model information to yield better performance.Monte Carlo simulation results are provided to illustrate the effectiveness and superior performance of the proposed state estimation and filter initialization methods. 展开更多
关键词 range-only measurement state estimation filter initialization target tracking unscented Kalman filter(UKF)
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神话英雄巴克狗--解读《野性的呼唤》(英文) 被引量:2
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作者 陈谦红 《思想战线》 CSSCI 北大核心 2008年第S3期41-42,共2页
This thesis is intended to interpret Jack London's The Call of the Wild from the per-spective of four western classical myths:the loss of happiness,initiation,the descent into hell and resurrection.This article is... This thesis is intended to interpret Jack London's The Call of the Wild from the per-spective of four western classical myths:the loss of happiness,initiation,the descent into hell and resurrection.This article is aimed at providing fans of The Call of the Wild with a new perspective in exploring the novel. 展开更多
关键词 MYTH lost HAPPINESS initiation descent into HELL RESURRECTION
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基于SIP多模式智能测控平台设计(英文)
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作者 周钦河 刘桂雄 洪晓斌 《科学技术与工程》 2009年第12期3311-3318,共8页
针对传统测控网络难以满足现代制造业多源数据、复杂数据格式的问题,设计了基于SIP的智能测控平台,建立基于SIP的智能测控网络结构,并对其智能接入、自我描述能力的数据传输、存在告知、异步事件通告、在线设备控制等功能进行规划。实... 针对传统测控网络难以满足现代制造业多源数据、复杂数据格式的问题,设计了基于SIP的智能测控平台,建立基于SIP的智能测控网络结构,并对其智能接入、自我描述能力的数据传输、存在告知、异步事件通告、在线设备控制等功能进行规划。实践证明,该智能测控平台较传统的测控网络拥有更完善的功能和更优秀的性能。 展开更多
关键词 智能测控平台 会话启动协议(Session INITIATION Protocal SIP) 数据描述协议(Data Description Protocol DDP)
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