瑞利面波椭圆极化在盾构隧道地层扰动探测中的应用

为解决传统物探方法在城市盾构隧道工程中难以对地层扰动达到较好探测和监测目的,提出了主动源瑞利面波椭圆极化方法. 采用二维有限元数值模拟对实际盾构隧道施工背景下的地层情况进行全波场正演模拟,并对其波场传播、速度频散和椭圆极化频散等特征进行分析;结合工程实例,进一步将椭圆极化方法和传统速度频散方法进行对比研究. 研究结果表明:主动源瑞利面波椭圆极化方法在探测地下介质结构分布及监测地下空洞等异常结构的变化方面具有和传统速度频散方法同样的探测效果,但由于其不需要长大检波器排列,对周围环境震动等噪声抗干扰能力相对较强,因此更适合城市等场地受限和具有一定震动和噪声干扰的环境,从而具有更广阔的应用前景.      

蜗壳截面形状对舰用离心泵性能特性的影响

为研究蜗壳截面形状对舰用离心泵性能的影响作为后续研究舰用离心泵噪声振动特性的理论依据,在蜗壳基圆、各断面面积、隔舌螺旋角、隔舌安放角和蜗壳出口面积相同的情况下,改变蜗壳截面形状,分别设计A型、B型和C型蜗壳。对3种蜗壳型式离心泵进行数值计算。结果表明,3种型式蜗壳离心泵的外特性变化趋势基本一致。小流量工况的A型蜗壳离心泵效率略小,大流量工况的B型和C型蜗壳离心泵效率小。随着流量的增大,B型和C型蜗壳离心泵效率下降幅度较大。3种型式蜗壳离心泵在相同工况条件下,压力场、速度场、湍动能和空化现象的变化趋势大致相同。3种型式蜗壳离心泵流场特性在隔舌流道和蜗壳流道处均不相同,表明改变蜗壳截面形状主要影响叶轮靠近隔舌流道和蜗壳流道内的流场。     

BUILDING OF A SIMPLE MODEL OF AUTO-OLT IN DOGS AND ITS SIGNIFICANCE

ＢＵＩＬＤＩＮＧＯＦＡＳＩＭＰＬＥ　ＭＯＤＥＬＯＦＡＵＴＯ－ＯＬＴＩＮＤＯＧＳ　ＡＮＤＩＴＳＳＩＧＮＩＦＩＣＡＮＣＥＫａｎｇＹａ＇ａｎ；，ＬｉＹｉｍｉｎｇ，ＪｉＺｏｎｇｚｈｅｎｇ；，ＱｉｎＺｈａｏｙｉｎ;（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｎｅｒａｌＳｕｒ?..     

Development of knowledge based body structure concept design model

The purpose of this study is to propose a concept design process for an automotive body structure using technical information on the major joints and members of vehicles. First, in order to collect the technical information on major joints and members, 17 vehicles were selected using benchmark data. The collected technical information for the selected vehicles was the cross sectional shapes of each joint and member which were used for the analysis of joint stiffness, crashworthiness and static stiffness of the member to make a database along with cross section properties. This study applied a ‘What If Study’ technique to perform a concept design of an automotive body using the analyzed information and selected cross section meeting the design objectives. The criteria for the selection of the cross section were defined by subdividing the defined design objectives of an automotive body structure and constraints into members and joints. In order to configure an analysis model of an automotive body structure using the selected cross section, a shape parametric model was used and static stiffness, dynamic stiffness and crashworthiness were assessed to evaluate the configured automotive body structure. The evaluation result showed that the crashworthiness and static/dynamic stiffness were improved compared to an existing body structure. In addition, the weight of the body structure was reduced. Through this study, the process that can rapidly and effectively derive and evaluate the concept design of an automotive body structure was defined. It is expected that, henceforth, this process will be helpful for the study of automotive body structures.     

黄陵县克山病病情现状

目的　观察克山病病情消长趋势 ,为防治和病情相关因素探索提供依据。方法　按“克山病监测”标准 (1 997年 )实施。结果　监测期内全县未见新发急 (亚急 )型克山病 ;监测点潜在型年新发生率 2 6 9/万 ;全县农业人群中慢型患病率 1 6 7/万 ,年新发现率 0 83/万 ,死亡率0 6 0 /万 ;在店头和腰坪两个重病乡镇 ,慢型年新发现率为 1 5 /万～ 1 8/万。结论　以急 (亚急 )型有无新发病及潜在型和慢型年新发生 (现患 )率为评估标准时 ,近 5年来黄陵县克山病病情稳定在 80年代中后期水平 ;慢型克山病是当前的防治重点。     

ANALYSIS OF PSYCHOLOGIC HEALTH STATE AND INFLUENCING FACTORS IN COLLEGE AND SECONDARY SCHOOL STUDENTS IN SHAANXI PROVINCE

It is necessary for educationists to knowstudents psychologic health state in colleges andmiddle schools.In recent years,there are lots of in-vestigations and researches on students psycholog-ic health state in colleges and middle schools.Re-sults have shown thatthe percentage ofcollege andmiddle school students psychologic disorder is be-tween1 0 and30 [1～ 5] .Shaanxi province lies in theNorthwestof China,thus its economics is compara-tively less developed.And also,there are lots ofcolleges…     

p16INK4/CDKN2在胆囊癌中的表达及临床意义

为明确p16基因及其产物在胆囊恶性肿瘤中表达的意义，用免疫组化ABC法对46例胆囊癌p16INK4／CDKN2表达进行检测，结果表明：p16INK4／CDKN2在良性病变中的阳性率高于胆囊癌（P＜0．05）。该蛋白的失活或缺失主要见于肿瘤的中、晚阶段，与胆囊外浸润和淋巴转移密切相关（P＜0．01），与肿瘤的病理类型及分化程度无关（P＞0．05）。检测p16INK4／CDKN2对临床正确地估计肿瘤的侵袭性、淋巴转移潜能及判断预后具有重要价值。     

增殖细胞核抗原在胃癌中的表达与淋巴结转移、预后的关系

为探讨增殖细胞核抗原 ( Proliferating cell nuclear antigen,PCNA)在胃癌的表达与淋巴结转移及预后的关系 ,采用免疫组化法 ( ABC法 )测定 94例胃癌石蜡包埋标本。结果 :1胃粘膜不同病理状态下 PCNA指数差异显著 ( P <0 .0 1 ) ;2PCNA指数同患者的性别和年龄无关 ( P >0 .0 5 ) ,与肿瘤的生长方式、组织类型、浆膜层受侵与否、淋巴结转移与否和临床分期关系密切 ( P <0 .0 5 ) ;3PCNA指数与胃癌的预后密切相关 ( P <0 .0 5 ) ,弱级 ( 1～ 2级 )表达的患者预后较好 ,提示 PCNA检测可作为判断胃癌生物学行为和预后的一项良好指标。     

《公路泥石流防治工程设计指南》梗概

泥石流是山区公路的主要病害。简述了《公路泥石流防治工程设计指南》（简称《指南》）的编写背景及依据,慨述了《指南》的主要技术框架以及《指南》应用过程中应注意的几个关键问题,为公路建设及养护等相关技术规范的修改提供了重要依据。     

微机联锁远程故障诊断系统的研究

作者论述了微机联锁远程故障诊断系统的构成和实现,提出现阶段信号维修改革的任务、组织管理、及实施远程故障诊断系统的关键技术。