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Values of endoscopic ultrasonography for diagnosis and treatment of duodenal protruding lesions 被引量:9
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作者 Guo-qiang XU Yi-qun WU +1 位作者 Li-jun WANG Hong-tan CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第4期329-334,共6页
Objective: The diagnoses of patients with duodenal protruding lesions are difficult when using conventional examinations such as computed tomography (CT) and conventional endoscope etc. Thus, we investigated the cl... Objective: The diagnoses of patients with duodenal protruding lesions are difficult when using conventional examinations such as computed tomography (CT) and conventional endoscope etc. Thus, we investigated the clinical value of endoscopic ultrasonography (PUS) with miniature ultrasonic probes on the diagnosis and treatment of duodenal protruding lesions. Methods: Patients with duodenal protruding lesions who were indicated for PUS were examined by PUS with 12-15 MHz miniature ultrasonic probes and double-cavity electronic endoscope. According to diagnosis of PUS, those patients were indicated for biopsy and treatment received biopsy, endoscopic resection or surgical excision. The postoperative histological results were compared with the preoperative diagnosis of PUS. Those patients without endoscopic resection or surgical excision were periodically followed up with PUS. Results: A total of 169 patients with duodenal protruding lesions were examined by PUS, of which 40 were diagnosed with cysts, 36 with inflammatory protruding or polyp, 25 with Brunner's gland adenoma, 19 with ectopic pancreas, 17 with gastrointestinal stromal tumor, 12 with extrinsic compression, 12 with minor papilla, 6 with lipoma, 1 with adenocarcinoma and 1 with lymphoma. After PUS examinations, 75 patients received biopsy, endoscopic resection or surgical excision respectively. The postoperative histological results of 70 patients were completely consistent with the preoperative diagnosis of PUS, with 93.33% diagnostic accuracy. The results of follow-up with PUS indicated that duodenal cyst, Brunner's gland adenoma, ectopic pancreas, gastrointestinal stromal tumor and lipoma remained unchanged within 1-3 years. No related complications occurred among all patients that received PUS examinations. Conclusion: PUS is an effective and reliable diagnostic method for duodenal protruding lesions. 展开更多
关键词 Endoscopic ultrasonography (EUS) Duodenal protruding lesions DIAGNOSIS FOLLOW-UP
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萌动小麦的干物质损耗与品质分析 被引量:10
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作者 李毅念 卢大新 +3 位作者 丁为民 胡志超 谢焕雄 张礼刚 《农业工程学报》 EI CAS CSCD 北大核心 2005年第8期190-192,共3页
对小麦籽粒经粒径分选和重力分选后获得的试样进行萌动发芽培养试验,从培养开始(0h)到24h之间以一定时间间隔对不同萌动状态的小麦进行干物质损耗测定和品质分析,结果表明干物质的损耗随着萌动时间的增加而增加;容重(比重)越小,干物质... 对小麦籽粒经粒径分选和重力分选后获得的试样进行萌动发芽培养试验,从培养开始(0h)到24h之间以一定时间间隔对不同萌动状态的小麦进行干物质损耗测定和品质分析,结果表明干物质的损耗随着萌动时间的增加而增加;容重(比重)越小,干物质的损耗呈现增大的趋势;各萌动时间段脂肪酸值则随着萌动时间的增加而增加;萌动籽粒的粗蛋白质含量较未萌动籽粒的低;萌动前期小麦籽粒的降落数值与未萌动籽粒相比基本上没有变化,而萌动后期的降落数值下降较快,表明此时淀粉酶的活性较高。 展开更多
关键词 小麦 萌动 干物质损耗 品质分析
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螺旋焊管成型缝“噘嘴”产生的原因及控制措施 被引量:8
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作者 侯永利 曹文军 《焊管》 2008年第2期75-76,共2页
分析了螺旋焊管制造过程中成型缝"噘嘴"现象产生的机理和原因,以及"噘嘴"现象对钢管质量的影响,并提出了制定最佳工艺参数、解决钢带钝边形状不合理、对钢带边缘进行预弯等解决"噘嘴"的有效控制方法。
关键词 螺旋焊管 成型 “噘嘴”
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双颌前突患者正畸辅助微螺钉种植体治疗前后的软组织侧貌 被引量:7
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作者 武冠英 杨琳 徐宝华 《中华医学美学美容杂志》 2013年第5期343-346,共4页
目的 通过直丝弓矫治器辅助微螺钉种植体对双颌前突患者进行拔牙矫治,对矫治前后的数据进行测量分析,评价对面部软组织侧貌的影响程度.方法 选择30例双颌前突患者,采用直丝弓矫治器辅助微螺钉种植体进行拔牙治疗.对矫治前后的头颅侧位X... 目的 通过直丝弓矫治器辅助微螺钉种植体对双颌前突患者进行拔牙矫治,对矫治前后的数据进行测量分析,评价对面部软组织侧貌的影响程度.方法 选择30例双颌前突患者,采用直丝弓矫治器辅助微螺钉种植体进行拔牙治疗.对矫治前后的头颅侧位X线片进行测量,分析治疗前后面部软组织的变化.结果 上切牙切端平均远中移动6.5 mm,上唇突点平均内收3.8 mm,下切牙切端平均远中移动5.8 mm,下唇突点平均内收5.6 mm,上唇平均向远中移动3.21 mm,下唇平均向远中移动3.67 mm,鼻唇角由治疗前的平均86.7°变为平均103.7°.上下前牙切端移动距离、上下唇突距、鼻唇角的变化差异有统计学意义.结论 直丝弓矫治器辅助微螺钉种植体对双颌前突患者进行拔牙矫治,有效地内收上下前牙,从而有效地改善面部软组织侧貌. 展开更多
关键词 双颌前突 拔牙矫治 软组织侧貌 微螺钉种植体 头影测量
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煤与瓦斯突出煤层巷道掘进工作面综合防突技术
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作者 郭斌斌 《科学技术创新》 2023年第18期217-220,共4页
本文将九里山矿在开采3#煤层时,面临的煤与瓦斯突出问题作为分析对象,对煤层出现的煤与瓦斯突出原因进行了分析,并结合煤层地质情况实际,采取了预抽瓦斯防突、超前卸压孔防突、高压注水防突、震动放炮防突等综合防突技术,从现场应用情... 本文将九里山矿在开采3#煤层时,面临的煤与瓦斯突出问题作为分析对象,对煤层出现的煤与瓦斯突出原因进行了分析,并结合煤层地质情况实际,采取了预抽瓦斯防突、超前卸压孔防突、高压注水防突、震动放炮防突等综合防突技术,从现场应用情况来看,取得较好的防突效果,对于工作面掘进过程出现的瓦斯超限问题得到了较好的解决,掘进的速度得到了显著的提升,有效缓解了采掘衔接较为紧张的问题,降低了煤与瓦斯出现突出事故的风险,保证了采掘工作的安全性。 展开更多
关键词 瓦斯 突出 煤层 巷道掘进 工作面 综合防突 技术
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Study on a Bowl-based Mechanism for Transplanting Potted Strawberry Seedlings
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作者 Yin Da-qing Yang Yu-chao +2 位作者 Zhou Mai-le Wei Ming-xu Wang Jin-wu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期56-68,共13页
To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to ac... To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to achieve rapid fetching and pushing bowl movements.According to the working principle of the slewing mechanism,a kinematics model and the optimization goal were established,respectively.Based on visual auxiliary analysis software,optimal parameters were obtained.A three-dimensional model was established to obtain a simulation trajectory by means of a virtual simulation design analysis.Three-dimensional printing technology was used to manufacture the test prototype,and the actual working trajectories of the test prototype were extracted using high-speed photography technology,which verified the consistency of the actual trajectory with the theoretical and simulated trajectories.A prototype transplanting experiment was performed with the success rate of seedling extraction of 91.2%and excellent planting rate of 82.8%,which met the requirements for integrated strawberry harvesting,planting and transplanting.The experimental results verified the correctness and feasibility of the design of integrated transplanting mechanism. 展开更多
关键词 potted strawberry seedlings potted seedling transplanting integrated planting mechanism protruding and pushing bowl type parameter optimization
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Automatic Determination of Yarn Hairiness Length Based on Image Processing and Analysis Algorithm 被引量:1
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作者 景军锋 黄梦莹 +2 位作者 李鹏飞 张蕾 张宏伟 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期587-591,共5页
A new algorithm is proposed to determine the actual length and the number of the protruding fibres of yarn based on a combination of image acquisition technology. First, a yarn hairiness image is obtained by the serie... A new algorithm is proposed to determine the actual length and the number of the protruding fibres of yarn based on a combination of image acquisition technology. First, a yarn hairiness image is obtained by the series of image processing procedures that include grayscale transformation,skew correction,yarn binary image acquisition and yarn core binary image obtaining. Then,the hairiness is realized in single pixel width by the usage of thinning algorithm. Finally, a baseline of yarn core margin is obtained,and pixels that match 8-neighbor template correctly are found by row scanning in a certain area. From this,these pixels are judged and the real crossover points of yarn core margin and hairiness,i. e.,the starting points of hairiness,are gained. The real length of the protruding fibres is calculated by tracking hairiness from the starting point constantly. 展开更多
关键词 protruding fibres of yarn image processing procedures hairiness thinning template matching tracking hairiness
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High temperature effects in moving shock reflection with protruding Mach stem 被引量:1
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作者 Xiaofeng Shi Yujian Zhu +1 位作者 Xisheng Luo Jiming Yang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第5期222-225,共4页
The influence of high temperature effects on the protrusion of Mach stem in strong shock reflection over a wedge was numerically investigated. A two-dimensional inviscid solver applies finite volume method and unstruc... The influence of high temperature effects on the protrusion of Mach stem in strong shock reflection over a wedge was numerically investigated. A two-dimensional inviscid solver applies finite volume method and unstructured quadrilateral grids were employed to simulate the flow. Theoretical analysis was also conducted to understand the phenomenon. Both numerical and theoretical results indicate a wall-jet penetrating forward is responsible for the occurrence of Mach stem protrusion. The protrusion degree seems to depend on the thermal energy buffer capacity of the testing gas. Approaches to increase the energy buffer capacity, such as vibrational relaxation, molecular dissociation, and increase of frozen heat caoacitv, all tend to escalate the orotrusion effect. 展开更多
关键词 Shock reflection Numerical simulation protruding Mach stem High temperature effects
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传动直丝弓技术与滑动直丝弓技术矫治成人双颌前突的疗效比较 被引量:3
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作者 郭奕 李天成 +1 位作者 彭诚 陈晶晶 《中华医学美学美容杂志》 2015年第4期219-222,共4页
目的 探讨传动直丝弓技术和MBT滑动直丝弓技术矫治成人双颌前突患者的临床效果.方法 选择双颌或双牙弓前突患者40例,将其完全随机分为两组,传动组20例,应用传动直丝弓矫治;MBT组20例,应用MBT滑动直丝弓结合口外弓或种植钉辅助支抗治疗.... 目的 探讨传动直丝弓技术和MBT滑动直丝弓技术矫治成人双颌前突患者的临床效果.方法 选择双颌或双牙弓前突患者40例,将其完全随机分为两组,传动组20例,应用传动直丝弓矫治;MBT组20例,应用MBT滑动直丝弓结合口外弓或种植钉辅助支抗治疗.比较两组头颅侧位X线治疗前后及治疗差值的组间差异.结果 平均疗程传动组为(19±4)个月,MBT组为(23±4)个月,差异有统计学意义(P<0.05);与治疗前比较,两组患者U1/SN、U1/NA、U1-NA、L1/NB、L1-NB、U1-AP、L1-AP、UL-EP、LL-EP均显著减小(P<0.01);U1/L1、鼻唇角和Z角均增大(P<0.05);MP/SN传动组增加1.93°(P<0.05),MBT组增加0.81°(P>0.05).除MP/SN差异有统计学意义外(P<0.05),其余差异均无统计学意义(P>0.05),但上中切牙内收量U1/NA传动组(-20.95±8.79)°明显大于MBT组(-16.00±6.52)°.结论 未使用额外支抗的传动技术和使用强支抗的MBT技术治疗双颌前突患者均能得到满意的软、硬组织结果.传动直丝弓技术能较早改善患者软组织侧貌,但上前牙有过于直立趋势,临床应注意上前牙的转矩控制. 展开更多
关键词 双颌前突 直丝弓矫正器 拔牙 软组织侧貌
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Experimental Study of Melting Heat Transfer in anEnclosure with Three Discrete Protruding HeatSources 被引量:3
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作者 YonglinJu ZhongqiChen 《Journal of Thermal Science》 SCIE EI CAS CSCD 1998年第2期111-118,共8页
To explore the possibility of using solid-liquid phase change cooling to those periodically or intermit-tently operated electronic equipment, a detail of experimeatal study of time-dependent melting heattransfer in a ... To explore the possibility of using solid-liquid phase change cooling to those periodically or intermit-tently operated electronic equipment, a detail of experimeatal study of time-dependent melting heattransfer in a rectangular encforure with three discrete protruding heat sources is presented. A seriesof experimntal measurement in an enclosure with phase change materials (PCM) of n-octadecaneheated by three discrete Protruding heat sources at a constant rate on one of its vertical wall has beendescribed. The opposite wall of the enclosure is cooled at a constant temperature and all other wallsof the enclosure are insulated. The time-dependent solid-liquid shapes of the interface during meltingprocess, the variation of surface temperature and the effects of subcooling are investigated. An empirical correlation predicting the relationship between tbe liquid phase fraction and subcooling is given. 展开更多
关键词 MELTING discrete protruding heat sources experimental study
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Thermal Analysis of a Phase Change Material Based Heat Sink for Cooling Protruding Electronic Chips 被引量:3
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作者 Mustapha FARAJI Hamid EL QARNIA EI Khadir LAKHAL 《Journal of Thermal Science》 SCIE EI CAS CSCD 2009年第3期268-275,共8页
This work aims to numerically study the melting natural convection in a rectangular enclosure heated by three discreet protruding electronic chips. The beat sources generate heat at a constant and uniform volumetric r... This work aims to numerically study the melting natural convection in a rectangular enclosure heated by three discreet protruding electronic chips. The beat sources generate heat at a constant and uniform volumetric rate. A part of the power generated in the heat sources is dissipated to a phase change material (PCM, n-eicosane with melting temperature, Tm = 36℃). Numerical investigations were carded out in order to examine the effects of the plate thickness on the maximum temperature of electronic components, the percentage contribution of plate heat conduction on the total removed heat and temperature profiles in the plate. Con'elations for the dimensionless secured working time (time to reach the threshold temperature, Tcr = 75℃) and the corresponding liquid fraction were derived. 展开更多
关键词 Phase change material protruding electronic component natural convection
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THE EFFECT OF THE CBN WHEEL DRESSING AND THE GRAIN HEIGHT PROTRUDING FROM THE BOND ON THE GRINDING PERFORMANCE
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作者 徐载熊 《Journal of China Textile University(English Edition)》 EI CAS 1989年第2期11-20,共10页
CBN (Cubic Boron Nitride) is a highly efficient abrasive and has unique properties (highhardness, high thermal stability and high chemical inertia). As early as 1969 CBN Wheels had al-ready been made and showed excell... CBN (Cubic Boron Nitride) is a highly efficient abrasive and has unique properties (highhardness, high thermal stability and high chemical inertia). As early as 1969 CBN Wheels had al-ready been made and showed excellent performance for grainding high speed steels and othermaterials hard to be ground. So far, however, CBN Wheels are still not popularly utilized in theindustry, the writer considers the main reason being the inadequate study for practical applica-tions and especially the suitable dressing technique. The dressing of resinoid CBN Wheels discussed in the paper, is different from that ofconventional ones. It has to be divided into two operations, truing and sharpening, each of whichhas its specific and independent functions. A simple dressing method with a lot of informationsuitable for production is studied; finally, the grain height protruding from the bond is taken asan index for evaluating the dressing results, and the effect of grain height on the grinding per-formance is discussed. By selecting proper conditions according to the workpiece requirements, abetter technical and economical benifit can be obtained. 展开更多
关键词 abrasive wheels grinding GRAIN size DRESSING truing and SHARPENING GRAIN HEIGHT protruding from the BOND CBN wheel
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The Protruding Property in Fuzzy Comprehensive Judgment
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作者 WANG Aimin(Department of Mathematics, Anyang teacher’s college Anyang, Henan 455000, China) 《Systems Science and Systems Engineering》 CSCD 1996年第3期345-348,共4页
When applying the comprehensive judgment model in making policies, we find that its protruding property is quite essential. Without this protruding property, policy-making be comes impossible and even contradictions e... When applying the comprehensive judgment model in making policies, we find that its protruding property is quite essential. Without this protruding property, policy-making be comes impossible and even contradictions emerge. this paper deals the protruding property and its influence on the comprehensive judgment, gives the full conditions for producing the protruding property and improves the model of the comprehensive judgment from the theory and the application. 展开更多
关键词 FUZZY Comprehensive judgment MODEL protruding property.
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试论人文精神在远程教学和管理中的张扬与凸现 被引量:2
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作者 徐皓 《江苏广播电视大学学报》 2000年第3期19-21,47,共4页
针对传统和现实教育中的弊端 ,根据远程教育的规律和特点 ,在简要阐述人文精神内涵及其价值取向的基础上 ,结合原国家教委批准的“专升本”英语教育专业试点 。
关键词 张扬 凸现 人文精神 远程教学 远程教育 教学管理
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炉围展开技术对强化炉膛辐射换热的分析 被引量:2
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作者 黄银洲 《四川冶金》 CAS 2005年第4期43-45,20,共4页
分析了炉膛综合辐射换热与强化措施,重点分析了采用内壁多凸起物的炉围展开技术等对炉膛辐射换热的强化作用及其在加热炉的设计与改造中的应用。
关键词 加热炉 辐射换热 炉围展开 凸起物 展开技术 强化措施 炉膛 强化作用
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刷子级进模设计 被引量:1
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作者 蔡敏 张东立 《模具工业》 2011年第6期21-25,共5页
通过对多向选择开关用刷子进行级进模设计,分析了刷子的冲压工艺及排样方案,针对V形弯曲提出了双滑块错时运动的设计理念,详细介绍了级进模的V形弯曲结构及双滑块结构。实践证明:模具结构合理,运行状态平稳,刷子零件质量优良。
关键词 刷子 级进模 V形弯曲 双滑块 打凸包
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Haptic Evaluation of the Prickle of Fabrics: Axial Compression Bending Tests On Ramie Fibers 被引量:1
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作者 刘宇清 韩露 于伟东 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期158-161,共4页
Although smoothness, softness, and stiffness determine the physical and mechanical behavior of a fabric and the subjective assessment of quality when it is handled, the perceived comfort of clothing is more important ... Although smoothness, softness, and stiffness determine the physical and mechanical behavior of a fabric and the subjective assessment of quality when it is handled, the perceived comfort of clothing is more important to consumers. The sensations perceived from the contact of clothing with the skin can greatly influence our over-all state of comfort and one aspect of this is the unpleasant skin sensation of prickle. Surface prickle of fabrics can be a factor limiting the use of the coarser types of ramie in apparel. And the mechanical stimulus of fabric-evoked prickle underlies our discomfort to fabrics independent in the majority of cases of any chemical or the atopic status of the individual. It is known that the prickle of fabric can be reduced by fabric-finishing treatments, but the assessment of fabric prickle is often done subjectively. This is time consuming, and it is difficult to obtain reliable and reproducible results, since variability between subjects in their sensitivity to prickle, such as skin mechanical properties, effective density of nociceptors and the mood state of the individual. In order to find an objective method of measuring the physical properties of the stiff fiber ends protruding from the fabrics to predict prickle, axial compression bending tests were examined by using single ramie fiber. By comparing analysis, it is found that the critical compressing load (Pcr), the bending modulus (E) are the important parameters. The relationship of the critical load (Pcr) with the length of fiber (L) and the fineness of fiber (Nt) has been investigated. 展开更多
关键词 PRICKLE Contact comfort protruding fiber Axial compression bending analyzer
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关于构建“四小”场所治安长效管理机制的调查与思考
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作者 张平 《公安理论与实践(上海公安高等专科学校学报)》 2003年第2期65-69,共5页
近年来,“四小”行业发展迅速,场所内经常发生黄、赌、毒等违法犯罪现象,治安问题比较突出。公安机关的多次集中专项整治,往往只能收一时之效。目前,公安机关对娱乐服务场所的行政审批权已被取消,“四小”场所治安管理工作将面临更大挑... 近年来,“四小”行业发展迅速,场所内经常发生黄、赌、毒等违法犯罪现象,治安问题比较突出。公安机关的多次集中专项整治,往往只能收一时之效。目前,公安机关对娱乐服务场所的行政审批权已被取消,“四小”场所治安管理工作将面临更大挑战,构建“四小”场所治安长效管理机制更加任重而道远。需要发挥政府综合管理的职能优势,有关职能部门之间要明确职责,形成社会治安综合治理的协调联动机制。 展开更多
关键词 治安长效管理机制 公安机关 专项整治工作 娱乐服务场所 中国
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一个向量值的鞍点定理
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作者 任晓 《西昌农业高等专科学校学报》 2001年第3期18-22,共5页
本文中,借助一些辅助定理,我们对一类鞍点问题进行了较为深入讨论,在较弱条件下得到了一个新的鞍点定理。
关键词 向量值 鞍点定理 凸性 C-鞍点
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某重力坝冲砂孔坝段地震动力反应规律及抗震安全性分析
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作者 袁平 王又武 +1 位作者 彭汉诗 何蕴龙 《工程建设》 2019年第4期10-17,共8页
以我国西南地区某重力坝冲砂孔坝段作为依托工程,应用三维有限元动力时程分析方法,针对坝顶特别宽厚、上游坝面突出及坝体内部布设孔洞等重力坝结构变动因素对大坝地震动力反应的影响规律开展了研究。研究结果表明,本坝段坝顶宽厚使得... 以我国西南地区某重力坝冲砂孔坝段作为依托工程,应用三维有限元动力时程分析方法,针对坝顶特别宽厚、上游坝面突出及坝体内部布设孔洞等重力坝结构变动因素对大坝地震动力反应的影响规律开展了研究。研究结果表明,本坝段坝顶宽厚使得坝顶部位结构刚度增强,导致坝顶地震反应加速度放大效应显著小于普通重力坝,坝体颈部的地震动应力集中不甚显著,地震动应力较小;上游坝面局部突出,导致坝体顺河向地震加速度呈现左侧小于右侧的不对称分布规律,外凸部分横河向地震加速度则明显大于坝体加速度。本文研究结论可为同类重力坝工程的抗震设计工作提供有益的参考。 展开更多
关键词 重力坝 坝顶厚 外凸 孔洞 地震动力反应 抗震安全性
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