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Numerical analysis of factors affecting the range of heat transfer in earth surrounding three subways

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Journal of China University of Mining and Technology 2008年第1期18卷 67-71页

作者： HU zeng-hui LI Xiao-zhao zhao Xiao-bao XIAO Lin WU Wei Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 China

In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.

关键词： earth surrounding subways range of heat transfer factors affecting heat transfer numerical analysis

Evolution laws of strength parameters of soft rock at the post-peak considering stiffness degradation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第4期15卷 282-290页

作者： zeng-hui zhao Wei-ming WANG Xin GAO State Key Laboratory of Mining Disaster Prevention and Control Co-foundedby Shandong Province and the Ministry of Science and Technology Qingdao 266590 China College of Mining and Safety Engineering Shandong University of Science and Technology Qingdao 266590 China College of Civil Engineering and Architecture Shandong University of Science and Technology Qingdao 266590 China

To evaluate the strength attenuation law of soft rock in the western mining area of China, we established an evolution model for the strength parameters of soft mudstone at the post-peak stage by employing a tri-linear strain softening model. In the model, a stiffness degradation coefficient co and a softening modulus coefficient a were introduced to take into account the stiff- ness degradation, and the subsequent yield surfaces at post-peak stage were all assumed to meet the Molar-Coulomb yield criterion. Furthermore, attenuation laws of stiffness and strength parameters of soft mudstone were analyzed according to an engineering case. Finally, the model＇s accuracy was verified by comparison of results from numerical calculation and tri-axial compression tests. Results showed that the attenuation of the friction angle was dominated mainly by the instantaneous stress states and damage features, while the attenuation law of cohesion was also related to the plastic behavior. The degradation rates of strength param- eters decreased with increasing confining pressure and the friction angle tended towards its initial value. Residual strengths were also enhanced with increasing confming pressure. The results indicate that the evolution model can accurately describe the strain softening behavior of soft rock.

关键词： Soft rock Strain softening Stiffness degradation Strength evolution Evolution law

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正交对称多小波构造及其图像压缩仿真研究

系统仿真学报 2010年第5期22卷 1246-1250,1256页

作者：曾朝晖湘潭大学信息工程学院湘潭411105

将参数化方法与遗传算法结合,设计出一种构造正交对称多小波的新方法。使用该方法,得到了具有任意消失矩的最优时频分辨率正交对称多小波,克服了前人的最优时频分辨率多小波仅具有二阶消失矩的不足。同时还给出了一系列在时频分辨率、... 详细信息

将参数化方法与遗传算法结合,设计出一种构造正交对称多小波的新方法。使用该方法,得到了具有任意消失矩的最优时频分辨率正交对称多小波,克服了前人的最优时频分辨率多小波仅具有二阶消失矩的不足。同时还给出了一系列在时频分辨率、正则指数等性质上都较前人更优的多小波。仿真实验表明,构造的部分多小波在纹理图像的压缩实验中,结果好于目前公认较好的多小波,在一定压缩比下还优于最好的单小波。

关键词：多小波消失矩 Sobolev正则指数最优时频分辨率正交性对称性图像压缩

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凹印包装设计的印刷工艺特点分析

包装工程 2008年第8期29卷 210-213页

作者：曾朝辉顺德职业技术学院顺德528300

从包装印刷设计的角度,结合行业实际情况以及实践经验,从凹印制版、包装材料、包装结构、印刷及后期加工等几个方面来论述凹印包装设计的印刷工艺特点。目的是为了加强凹印包装生产各工序的配合,提高包装设计师以及艺术设计院校师生对... 详细信息

从包装印刷设计的角度,结合行业实际情况以及实践经验,从凹印制版、包装材料、包装结构、印刷及后期加工等几个方面来论述凹印包装设计的印刷工艺特点。目的是为了加强凹印包装生产各工序的配合,提高包装设计师以及艺术设计院校师生对凹印包装印刷工艺的认识和把握,促进凹印包装设计效率和印刷品质量的改善。

关键词：凹印包装设计制版印刷工艺

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基于自适应混合优化的电力数据预测方法

控制与决策 2023年第12期38卷 3490-3498页

作者：曾朝晖赵会勇罗恩韬张英豪杨阳严一泰湘潭大学智能计算与信息处理教育部重点实验室湖南湘潭411105 湖南科技学院信息工程学院湖南永州425099

电力数据易受气候、季节、节假日等因素影响,出现不同波动特征.针对不同特征电力数据预测精度不高、预测方法泛化能力弱等问题,提出基于自适应混合优化的电力数据预测方法.通过使用小波变换和平稳性分析,将电力数据自适应地分解为包含... 详细信息

电力数据易受气候、季节、节假日等因素影响,出现不同波动特征.针对不同特征电力数据预测精度不高、预测方法泛化能力弱等问题,提出基于自适应混合优化的电力数据预测方法.通过使用小波变换和平稳性分析,将电力数据自适应地分解为包含趋势、季节和周期信息的非平稳序列和多个平稳序列;使用状态转移算法分别优化长短时记忆深度学习网络和自回归移动平均模型,对非平稳序列和平稳序列分别拟合、预测;对预测的各序列进行重构,得到最终预测结果.在电力系统数据上进行多步预测,对比实验表明:与其他方法相比,所提方法不仅具有更高的预测精度,还具有较强的泛化能力.

关键词：电力数据预测长短期记忆深度学习网络自回归移动平均模型小波分解状态转移算法

MANET中一种基于移动预测的单向QoS路由

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小型微型计算机系统 2006年第12期27卷 2246-2250页

作者：邓曙光曾朝晖曾专武湖南城市学院东南大学国家移动通信重点实验室江苏南京210096

针对MANET中QoS需求与隐藏终端等问题,提出了一种基于移动预测的单向QoS路由协议.该协议充分利用网络中存在的单向链路,采用移动预测机制,通过选取满足QoS条件的最稳路径的方式为数据流选择最佳路由.分析和实验结果表明,这种协议具有数... 详细信息

针对MANET中QoS需求与隐藏终端等问题,提出了一种基于移动预测的单向QoS路由协议.该协议充分利用网络中存在的单向链路,采用移动预测机制,通过选取满足QoS条件的最稳路径的方式为数据流选择最佳路由.分析和实验结果表明,这种协议具有数据包传送成功概率高和控制开销低等优点,能有效支持单向MANET中具有QoS需求的多媒体信息传输.

关键词： MANET 移动预测单向链路 QoS路由

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基于遗传算法的正交对称多小波构造

计算机工程 2010年第11期36卷 209-211页

作者：曾朝晖刘亚军湘潭大学信息工程学院湘潭411105 天津大学管理学院天津300072 湘潭大学商学院湘潭411105

在多小波参数化的基础上,利用遗传算法的全局优化能力,将带参数的正则指数函数作为遗传算法的适应度函数,构造出正则指数较高的多小波。与其他具有相等支撑长度、消失矩阶数及滤波器结构的多小波相比,该多小波的正则指数更优。对光滑和... 详细信息

在多小波参数化的基础上,利用遗传算法的全局优化能力,将带参数的正则指数函数作为遗传算法的适应度函数,构造出正则指数较高的多小波。与其他具有相等支撑长度、消失矩阶数及滤波器结构的多小波相比,该多小波的正则指数更优。对光滑和纹理图像的压缩和去噪的实验结果表明,该多小波的图像处理能力更强、效果更好。

关键词：多小波遗传算法正则性图像压缩图像去噪

Failure characteristics of three-body model composed of rock and coal with different strength and stiffness

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Transactions of Nonferrous Metals Society of China 2014年第5期24卷 1538-1546页

作者：赵增辉王渭明代春泉严纪兴山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地青岛266590 山东科技大学矿业与安全工程学院青岛266590 山东科技大学土木工程与建筑学院青岛266590

Four different types of three-body model composed of rock and coal with different strength and stiffness were established in order to study the failure characteristics of compound model such as roof-coal-floor. Through stress analysis of the element with variable strength and stiffness extracted from the strong-weak interface, the tri-axial compressive strength of the weak body and strong body near the interface as well as the areas away from the contact surface was found. Then, on the basis of three-dimensional fast Lagrangian method of continua and strain softening constitutive model composed of Coulomb-Mohr shear failure with tensile cut-off, stress and strain relationship of the four three-body combined models were analyzed under different confining pressures by numerical simulation. Finally, the different features of local shear zones and plastic failure areas of the four different models and their development trend with increasing confining pressure were discussed. The results show that additional stresses are derived due to the lateral deformation constraints near the strong-weak interface area, which results in the strength increasing in weak body and strength decreasing in strong body. The weakly consolidated soft rock and coal cementation exhibit significant strain softening behavior and bear compound tension-shear failure under uni-axial compression. With the increase of confining pressure, the tensile failure disappears from the model, and the failure type of composed model changes to local shear failure with different number of shearing bands and plastic failure zones. This work shows important guiding significance for the mechanism study of seismic, rock burst, and coal bump.

关键词： three-body model composed of rock and coal strength near strong-weak interface local shear band plastic failure zone

MANET中一种基于单向链路的QoS路由协议

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计算机工程与应用 2006年第29期42卷 160-162,166页

作者：邓曙光曾朝晖习胜丰湖南城市学院

MANET是由一系列动态节点主机临时组成的多跳性无线网络。由于其拓扑的动态性,传统路由协议不再适应本网络。为降低控制开销,满足QoS需求,并考虑到隐藏终端等问题,论文提出了一种基于单向链路的QoS路由协议QRUL。该协议采用按需方式查... 详细信息

MANET是由一系列动态节点主机临时组成的多跳性无线网络。由于其拓扑的动态性,传统路由协议不再适应本网络。为降低控制开销,满足QoS需求,并考虑到隐藏终端等问题,论文提出了一种基于单向链路的QoS路由协议QRUL。该协议采用按需方式查找路由,并通过选取满足QoS条件(链路带宽和传输延时)的最短传输路径来实现。仿真结果表明该协议具有良好的网络性能,能有效支持多媒体信息传输。

关键词： MANET 单向链路 QoS路由