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一种应用于D类音频放大器的CMOS振荡器的设计

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电子元器件应用 2012年第8期14卷 49-51,68页

作者：何钦王丹西南交通大学信息科学与技术学院四川成都610031

文中介绍了一种应用于低D类音频功放的CMOS振荡器结构设计,用于对音频信号的调制。振荡器采用内部正反馈的迟滞比较器设计,大大降低了电源电压和环境温度对CMOS振荡器振荡频率的影响。理论分析及仿真结果表明,此CMOS振荡器具有较高的频... 详细信息

文中介绍了一种应用于低D类音频功放的CMOS振荡器结构设计,用于对音频信号的调制。振荡器采用内部正反馈的迟滞比较器设计,大大降低了电源电压和环境温度对CMOS振荡器振荡频率的影响。理论分析及仿真结果表明,此CMOS振荡器具有较高的频率稳定性。

关键词：振荡器 D类音频放大器迟滞比较器

A Design Strategy for Product Development Using Anthropometry

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A Design Strategy for Product Development Using Anthropometr...

2010 International Conference on Advanced Measurement and Test (AMT 2010)

作者： Yefei Li 1,a,Fangyu Li 2,b,Hui Jiang 3,c,Fang Huang 4,d 1 school of Mechatronics Engineering,university of Electronic science and technology of china,chengdu,Sichuan,611731,P.R.C 2 school of Arts and Communications,southwest jiaotong university,chengdu,Sichuan,611756,P.R.C 3 school of Microelectronics and Solid State Electronics,university of Electronic science and technology of china,chengdu,Sichuan,610054,P.R.C 4 school of Automation,university of Electronic science and technology of china,chengdu,Sichuan,611731,P.R.C

To achieve success in the marketplace,human factors play an important role in product *** this paper a design strategy considering anthropometric variability for different demographic data was put *** the aid of parametric technology of Computed Aided Design(CAD),concept model of products was *** parameters of products were configured according to the anthropometric information based on measurement of customers'.Multiple linear regression were used to model the relation between the product comfort and design variables,thus the sizes of products could adapt to specific customers of certain age,height and gender.A children's scooter was demonstrated as a case to validate this strategy.A three dimension parametric model of a scooter was built first,the parameters concerned with human factors were determined according to the knowledge of anthropometry.

关键词： design strategy,human factors,product design,anthropometric measurement

双坡面临空岩质边坡滑动破坏模式下的稳定性分析

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山地学报 2006年第4期24卷 446-449页

作者：周应华周德培邵江西南交通大学土木工程学院西南交通大学土木工程学院四川成都610031

多数岩质边坡稳定性分析已基本解决了常走向单坡面临空的边坡平面滑动问题。然而,在路堑边坡工程和自然边坡中有很多边坡坡面并不是平面,它包含多个坡面。多坡面边坡包含两个或多个不同走向的坡面。多坡面边坡几何特征不同于单坡面边坡... 详细信息

多数岩质边坡稳定性分析已基本解决了常走向单坡面临空的边坡平面滑动问题。然而,在路堑边坡工程和自然边坡中有很多边坡坡面并不是平面,它包含多个坡面。多坡面边坡包含两个或多个不同走向的坡面。多坡面边坡几何特征不同于单坡面边坡,所以滑动条件也不一样。在赤平投影图上,多坡面的滑动包络线是组成边坡的每个坡面单独投影包络线的组合。为了探讨方便,只讨论了双坡面临空岩质边坡的滑动破坏模式,并将其分为双坡面临空下的平面破坏和楔形体破坏。在赤平投影图上,双坡面滑动区域定义为双坡面边坡滑动包络图中两侧坡面的真倾线之间的面积。如果有一两个节理面真倾向线落在滑动区内,滑动破坏才可能发生。

关键词：双坡面临空边坡单坡面临空边坡岩质边坡赤平投影稳定性分析

A numerical study of contact force in competitive evacuation

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Chinese Physics B 2017年第10期26卷 295-301页

作者：林鹏马剑司有亮吴凡雨王国元王建宇 Department of Fire Safety Engineering Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Chengdu 610031 China school of Transportation and Logistics Southwest Jiaotong University Chengdu 610031 China

Crowd force by the pushing or crushing of people has resulted in a number of accidents in recent decades. The aftermath investigations have shown that the physical interaction of a highly competitive crowd could produce dangerous pressure up to 4500 N/m, which leads to compressive asphyxia or even death. In this paper, a numerical model based on discrete element method （DEM） as referenced from granular flow was proposed to model the evacuation process of a group of highly competitive people, in which the movement of people follows Newton＇s second law and the body deformation due to compression follows Hertz contact model. The study shows that the clogs occur periodically and flow rate fluctuates greatly if all people strive to pass through a narrow exit at high enough desired velocity. Two types of contact forces acting on people are studied. The first one, i.e., vector contact force, accounts for the movement of the people following Newton＇s second law. The second one, i.e., scale contact force, accounts for the physical deformation of the human body following the contact law. Simulation shows that the forces chain in crowd flow is turbulent and fragile. A few narrow zones with intense forces are observed in the force field, which is similar to the strain localization observed in granular flow. The force acting on a person could be as high as 4500 N due to force localization, which may be the root cause of compressive asphyxia of people in many crowd incidents.

关键词： crowd flow discrete element method (DEM) contact force force localization

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基于优势与劣势分析的DEA综合评价方法

西南师范大学学报（自然科学版） 2004年第3期29卷 357-360页

作者：张俊容郭耀煌西南交通大学经济管理学院

提出了基于数据包络法的劣势效率评价模型,将其与现有数据包络模型结合起来,得到了一种综合评价决策单元相对有效性的效率评价方法.该方法分别从有利于被评决策单元和不利于被评决策单元的角度对被评决策单元的相对有效性进行研究,由此... 详细信息

提出了基于数据包络法的劣势效率评价模型,将其与现有数据包络模型结合起来,得到了一种综合评价决策单元相对有效性的效率评价方法.该方法分别从有利于被评决策单元和不利于被评决策单元的角度对被评决策单元的相对有效性进行研究,由此得到其综合有效性值,据此可以对决策单元进行排序.

关键词：数据包络法相对有效性效率评价

Logistics Field Theory and Model

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Logistics Field Theory and Model

第一届交通运输工程国际学术会议

作者： TANG Yin-ying1,PENG Qi-yuan1, and LI Li2 1school of Traffic and Transp.,southwest jiaotong university,chengdu 610031, china. 2school of machinary and traffic Xinjiang Agricultural university,Urumqi, 830052

The characteristics of logistics space structure are researched and the "field theory" is applied to the research of logistics. The logistics field theory is put forward and the characteristics of it are discussed. Based on the analysis of logistics "field effect", the "node", "line", "plane" models of logistics effect field and space structure are constructed in the paper. The logistics enterprises develop motivities are discussed and the motivity field models are further constructed.

关键词： logistics logistics effect field field intensity node motivity field1

THE RELATIONSHIP OF URBANIZATION AND THE DEVELOPMENT OF TRANSPORTATION INDUSTRY:A NEW ANALYTICAL APPROACH FROM NEW CLASSICAL ECONOMICS

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THE RELATIONSHIP OF URBANIZATION AND THE DEVELOPMENT OF TRAN...

第一届交通运输工程国际学术会议

作者： LI Ming1 and HUANG Lanqiu2 1College of Traffic and Transportation, southwest jiaotong university, P.O. Box 610031, chengdu, china 2 school of Economics and Management, South china Normal university, P.O. Box 510006, Guangzhou, china

It is difficult to analyze the relationship between urbanization and division of Labor in Neoclassical Economics. Nevertheless, New Classical Economics offers powerful methods to deal with the complex relations between specialization and division of labor. Using the new classical framework, this paper analyzes the producer-consumers’ region choice mode of transportation industry, indicated that urbanization could promote the development of transportation industry. On the basis of these, this paper further analyzes how the productivity promotion of transportation industry and production innovation affected urbanization. Finally, we find out that the productivity promotion of transportation Industry and production innovation are important to increase urbanization.

关键词： new classical economics division urbanization transportation industry

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汉字笔顺教学仪

江西蓝天学院学报 2011年第1期6卷 39-44页

作者：邱云平韩诚西南交通大学信息科学与技术学院

本设备包括红外遥控发射器和LED点阵显示屏两部分。点阵LED驱动控制芯片选择专用集成电路ZLG7289,主控芯片采用80C51单片机。红外遥控发射器用来输入、选择和发送要显示的汉字信息并控制笔顺的演示,LED显示屏用作汉字笔顺演示。红外遥... 详细信息

本设备包括红外遥控发射器和LED点阵显示屏两部分。点阵LED驱动控制芯片选择专用集成电路ZLG7289,主控芯片采用80C51单片机。红外遥控发射器用来输入、选择和发送要显示的汉字信息并控制笔顺的演示,LED显示屏用作汉字笔顺演示。红外遥控发射器由键盘输入电路、显示电路、红外发射电路和单片机控制电路组成。LED显示屏由红外接收电路、LED显示电路和单片机控制电路组成。本设备是以单片机为核心控制红外遥控发射器和LED点阵显示屏电路来实现汉字笔顺教学的目的。

关键词：红外遥控 LED点阵显示屏 80C51 ZLG7289

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均质边坡分级开挖宽平台设计初探

山地学报 2007年第3期25卷 381-384页

作者：周应华周德培铁道部第二勘察设计院交通设计研究分院西南交通大学土木工程学院四川成都610031

对整体稳定性较差的高边坡,在地形条件允许的情况下,建议在边坡中部设置宽平台。平台宽度达到一定值时,可使边坡平台上下级开挖互不影响,这样做的好处是当边坡产生局部失稳时就不会波及其他级边坡,从而避免从上到下连续大滑坡。提出采... 详细信息

对整体稳定性较差的高边坡,在地形条件允许的情况下,建议在边坡中部设置宽平台。平台宽度达到一定值时,可使边坡平台上下级开挖互不影响,这样做的好处是当边坡产生局部失稳时就不会波及其他级边坡,从而避免从上到下连续大滑坡。提出采用极限平衡法搜索滑面的方法来确定宽平台的合理宽度,并用数值分析结果验证这种方法的合理性。进行了宽平台设计因子相关性分析,并建议采用工程类比的方法结合上述宽平台设计因子相关性找出一个较为合理的边坡开挖坡率和宽平台值。

关键词：均质边坡宽平台设计