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A Test Pattern Identification Algorithm and Its Application to CINRAD/SA(B) Data
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作者 JIANG Yuan LIU Liping 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期331-343,共13页
A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,"test pattern" caused by test signal... A variety of faulty radar echoes may cause serious problems with radar data applications,especially radar data assimilation and quantitative precipitation estimates.In this study,"test pattern" caused by test signal or radar hardware failures in CINRAD (China New Generation Weather Radar) SA and SB radar operational observations are investigated.In order to distinguish the test pattern from other types of radar echoes,such as precipitation,clear air and other non-meteorological echoes,five feature parameters including the effective reflectivity data percentage (Rz),velocity RF (range folding) data percentage (RRF),missing velocity data percentage (RM),averaged along-azimuth reflectivity fluctuation (RNr,z) and averaged along-beam reflectivity fluctuation (RNa,z) are proposed.Based on the fuzzy logic method,a test pattern identification algorithm is developed,and the statistical results from all the different kinds of radar echoes indicate the performance of the algorithm.Analysis of two typical cases with heavy precipitation echoes located inside the test pattern are performed.The statistical results show that the test pattern identification algorithm performs well,since the test pattern is recognized in most cases.Besides,the algorithm can effectively remove the test pattern signal and retain strong precipitation echoes in heavy rainfall events. 展开更多
关键词 quality control test pattern fuzzy logic radar data
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Enhancing SAT-Based Test Pattern Generation
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作者 刘歆 熊有伦 《Journal of Electronic Science and Technology of China》 2005年第2期134-139,共6页
This paper presents modeling tools based on Boolean satisfiability (SAT) to solve problems of test generation for combinational circuits. It exploits an added layer to maintain circuit-related information and value ju... This paper presents modeling tools based on Boolean satisfiability (SAT) to solve problems of test generation for combinational circuits. It exploits an added layer to maintain circuit-related information and value justification relations to a generic SAT algorithm. It dovetails binary decision graphs (BDD) and SAT techniques to improve the efficiency of automatic test pattern generation (ATPG). More specifically, it first exploits inexpensive reconvergent fanout analysis of circuit to gather information on the local signal correlation by using BDD learning, then uses the above learned information to restrict and focus the overall search space of SAT-based ATPG. Its learning technique is effective and lightweight. The experimental results demonstrate the effectiveness of the approach. 展开更多
关键词 test pattern generation fault detection Boolean satisfiability binary decision graphs
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Study on Test Compaction in High-Level Automatic Test Pattern Generation (ATPG) Platform 被引量:1
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作者 Ayub Chin Abdullah Chia Yee Ooi 《Circuits and Systems》 2013年第4期342-349,共8页
Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic t... Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic test pattern generation (ATPG). In addition, ATPG needs to deal with new defects caused by process variation when IC is shrinking. To reduce the computation effort of ATPG, test generation could be started earlier at higher abstraction level, which is in line with top-down design methodology that has become more popular nowadays. In this research, we employ Chen’s high-level fault model in the high-level ATPG. Besides shorter ATPG time as shown in many previous works, our study showed that high-level ATPG also contributes to test compaction. This is because most of the high-level faults correlate with the gate-level collapsed faults especially at input/output of the modules in a circuit. The high-level ATPG prototype used in our work is mainly composed by constraint-driven test generation engine and fault simulation engine. Experimental result showed that more reduced/compact test set can be generated from the high-level ATPG. 展开更多
关键词 Automatic test pattern Generation (ATPG) Constraint Logic Programming (CLP) Verilator Circuit-Under-test (CUT) test COMPACTION
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Efficient Static Compaction of Test Patterns Using Partial Maximum Satisfiability
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作者 Huisi Zhou Dantong Ouyang Liming Zhang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2021年第1期1-8,共8页
Static compaction methods aim at finding unnecessary test patterns to reduce the size of the test set as a post-process of test generation.Techniques based on partial maximum satisfiability are often used to track man... Static compaction methods aim at finding unnecessary test patterns to reduce the size of the test set as a post-process of test generation.Techniques based on partial maximum satisfiability are often used to track many hard problems in various domains,including artificial intelligence,computational biology,data mining,and machine learning.We observe that part of the test patterns generated by the commercial Automatic Test Pattern Generation(ATPG)tool is redundant,and the relationship between test patterns and faults,as a significant information,can effectively induce the test patterns reduction process.Considering a test pattern can detect one or more faults,we map the problem of static test compaction to a partial maximum satisfiability problem.Experiments on ISCAS89,ISCAS85,and ITC99 benchmarks show that this approach can reduce the initial test set size generated by TetraMAX18 while maintaining fault coverage. 展开更多
关键词 test compaction partial maximum satisfiability Automatic test pattern Generation(ATPG)
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Ultrasonic Testing Combined with Pattern Recognition for the Detection of Kissing Bonds
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作者 Jens Schuster David Müller +1 位作者 Ming-Hong Chen Quentin Govignon 《Open Journal of Composite Materials》 2019年第3期260-270,共11页
Kissing bonds are defects in the adhesive bonds with intimate contact of touching surface but considerably lowered shear strength. Their detection specifically in the aerospace area is so not satisfactory. Usually, ki... Kissing bonds are defects in the adhesive bonds with intimate contact of touching surface but considerably lowered shear strength. Their detection specifically in the aerospace area is so not satisfactory. Usually, kissing bonds are inconspicuous in ultrasonic C-scans. However, the determination of attributes in the time domain and the frequency domain of an ultrasound signal provides the opportunity to derive a pattern for bonded area. Deviations from the pattern found in inconspicuous bonding areas indicate kissing bonds. The survey described here deals with the manufacturing of adhesively joint samples that purposefully include kissing bonds, as well as potential solutions for detecting them through ultrasonic testing combined with pattern recognition. The properties of the epoxy-based adhesive were varied by changing the mixing ratios between resin and hardener. Samples with a mixing ratio far apart from the manufacturer’s recommendation with an inconspicuous appearance in a C-scan, but low shear strength values were taken for further evaluation. After a definition and learning phase, a 100 percent hit rate to separate good bondings from kissing bonds could be derived in a blind test. The discriminating feature found is due to the frequency shift between good and kissing bonds as well as the relative amplitude of the second peak. 展开更多
关键词 ULTRASONIC testing Time DOMAIN Frequency DOMAIN pattern RECOGNITION BOND Quality KISSING BOND
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鄂尔多斯盆地东缘深部煤层气开发先导试验效果与启示 被引量:2
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作者 聂志宏 徐凤银 +10 位作者 时小松 熊先钺 宋伟 张雷 刘莹 孙伟 冯延青 刘世瑞 闫霞 孙潇逸 吴满生 《煤田地质与勘探》 EI CAS CSCD 北大核心 2024年第2期1-12,共12页
鄂尔多斯盆地东缘大宁-吉县区块深部煤层气勘探开发取得突破对煤层气产业带来重大影响,引起业内广泛关注和跟进。前期一些学者对深部煤层气勘探开发理论技术难点与对策开展了研究,但缺乏对典型气田开发先导试验系统总结。通过深入剖析... 鄂尔多斯盆地东缘大宁-吉县区块深部煤层气勘探开发取得突破对煤层气产业带来重大影响,引起业内广泛关注和跟进。前期一些学者对深部煤层气勘探开发理论技术难点与对策开展了研究,但缺乏对典型气田开发先导试验系统总结。通过深入剖析深部煤层气地质特征与效益开发难点,总结大宁-吉县区块开发先导试验项目取得的进展和成效,明确开发规律并提出效益开发对策。结果表明:(1)深部煤层具有广覆式发育、含气性好、游离气含量高、保存条件好、煤体结构好、脆性指数高、顶底板封盖性强等地质特征,但微构造发育、渗透性极差、矿化度高等因素制约了深部煤层气效益开发;(2)不同地质条件下气井生产特征差异较大,通过先导试验落实气井产能和适应性开发技术对策,采用滚动开发模式可有效降低煤层强非均质性带来的开发风险;(3)开展地质-工程一体化井网优化设计,构建井网与缝网高度弥合的人造气藏,可实现资源动用和采收率最大化;(4)“长水平段+多段多簇+大砂量”的大规模、大排量极限体积压裂技术可增大有效改造体积和井控储量,大幅提高单井产量;(5)深部煤层气井具有“见气时间短、上产速度快、初期产量高、递减快”的生产特征,可实现短期快速规模上产,但气田长期稳产需持续新井投入;(6)前期开发成本偏高,实现效益开发需不断提高工程作业效率、降低开发成本。综合认为,深部煤层气资源品质好,可动用性强,具备快速推广复制条件,大宁-吉县区块深部煤层气开发实践可为国内其他区块深部煤层气规模动用提供技术借鉴,对加快深部煤层气规模勘探开发具有重要意义。 展开更多
关键词 鄂尔多斯盆地东缘 大宁-吉县区块 深部煤层气 先导试验 开发规律 极限体积压裂技术
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Reporting Children’s Development below the Test Floor: Looking Back and Forth to Describe Individual Strengths and Needs
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作者 Elizabeth M. Green Louise A. Stroud 《Health》 CAS 2023年第2期122-133,共12页
The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners reques... The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners requested advice on the reporting of children’s development below the floor of the test, so that individual strengths and needs can be described. This paper reports the third phase of research following an earlier Scoping Review and a wider literature review. To confirm quality control, Phase 3 was conducted in a retrospective manner using the same methodology as the earlier phases but in a reverse direction. Peer reviewer comments and key elements from the Scoping Review and keywords from the publications were tabulated. Data analysis included a change of perspective to that of the child and their individual rights with respect to the literature themes already described in Phase 2. These confirmed that there is little specific guidance in the literature, but that computational advances for homogeneous populations and especially disaggregated data offer some solutions. A greater balance between broad biopsychosocial models and standardised models of assessment should be sought by practitioners together with the use of disaggregated data to highlight issues that pertain to individual subsets of results. This will ensure that the child’s right for their individual strengths and needs to be described together with a plan for management, may be met. 展开更多
关键词 Developmental Assessment Children with Severe Disability Disaggregated Data pattern and Needs Identification Below test Floor
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信江八字嘴枢纽工程整体水工模型试验研究
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作者 涂晓霞 刘博文 《江西水利科技》 2024年第1期42-47,共6页
根据工程建设的需要,为了全面验证枢纽建筑物整体布置方案的合理性,对江西信江八字嘴枢纽工程进行了整体水工模型试验。通过模型试验研究其水力特性和流态,在满足消能防冲的条件下,创造安全的通航水流条件,确定了枢纽整体布置形式和消... 根据工程建设的需要,为了全面验证枢纽建筑物整体布置方案的合理性,对江西信江八字嘴枢纽工程进行了整体水工模型试验。通过模型试验研究其水力特性和流态,在满足消能防冲的条件下,创造安全的通航水流条件,确定了枢纽整体布置形式和消能工体型。试验成果优化了枢纽建筑物布置方案,为工程设计提供了技术依据。 展开更多
关键词 八字嘴枢纽 水工模型试验 水力特性 流态
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基于ATE的千级数量管脚FPGA多芯片同测技术
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作者 秦立君 余永涛 +2 位作者 罗军 李军求 庞水全 《电子技术应用》 2024年第7期51-54,共4页
随着超大规模FPGA芯片技术发展,芯片管脚数量提升到1000以上,如何实现超大规模多引脚FPGA芯片高效测试成为ATE在线测试难点。针对一款千级数量管脚超大规模的FPGA芯片,基于FPGA的可编程特性,采用多芯片有效pin功能并行测试和单芯片全pi... 随着超大规模FPGA芯片技术发展,芯片管脚数量提升到1000以上,如何实现超大规模多引脚FPGA芯片高效测试成为ATE在线测试难点。针对一款千级数量管脚超大规模的FPGA芯片,基于FPGA的可编程特性,采用多芯片有效pin功能并行测试和单芯片全pin电性能参数测试相结合的方法进行ATE测试,实现了千级数量管脚FPGA芯片的4芯片同测,测试效率提升3倍多。 展开更多
关键词 现场可编程门阵列 自动化测试系统 多芯片同测 功能测试
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泥石流中球形巨石运动规律模型试验研究
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作者 娄灿昀 王飞 +1 位作者 王家鼎 陈晓清 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期133-144,共12页
该研究通过室外水槽模型试验,模拟了不同直径巨石与不同密度泥石流完全固液耦合作用下的运动状态,分析了泥石流沟内巨石在泥石流中的运动模式、运动的影响因素及其在泥石流中的受力情况,并探讨了泥石流密度与巨石粒径对其运动速度的影... 该研究通过室外水槽模型试验,模拟了不同直径巨石与不同密度泥石流完全固液耦合作用下的运动状态,分析了泥石流沟内巨石在泥石流中的运动模式、运动的影响因素及其在泥石流中的受力情况,并探讨了泥石流密度与巨石粒径对其运动速度的影响。研究结果表明:巨石在运动过程中可能出现滚动、跳跃与滑动等运动模式,巨石出现的运动模式同泥石流的密度以及巨石粒径有关;巨石的直径越大,运动速度越小,它在泥石流中的运动模式越简单,越倾向于发生滚动运动,在泥石流流体中的跟随性越好,速度比n越容易趋近于1;巨石粒径对巨石运动速度的影响大于泥石流密度对它的影响。 展开更多
关键词 泥石流 球形巨石 水槽试验 运动规律
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110 kV干式空心并联电抗器振动台试验与易损性研究
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作者 李吉超 罗清宇 +2 位作者 张宏 贺军 李建赢 《防灾减灾工程学报》 CSCD 北大核心 2024年第1期50-58,共9页
电抗器是变电站的重要设备之一,上部线圈由底部陶瓷绝缘子支撑,整体尺寸大、重心高。由于结构形式的特殊性,其在地震作用下的动力响应较为复杂。本文对110 kV干式空心并联电抗器进行了振动台试验研究,通过白噪声测定了电抗器的自振频率... 电抗器是变电站的重要设备之一,上部线圈由底部陶瓷绝缘子支撑,整体尺寸大、重心高。由于结构形式的特殊性,其在地震作用下的动力响应较为复杂。本文对110 kV干式空心并联电抗器进行了振动台试验研究,通过白噪声测定了电抗器的自振频率和阻尼比;在0.15g和0.5g人工地震动输入下,测量了电抗器关键部位的应变、加速度和位移响应,分析了电抗器在地震作用下的动力响应规律,探讨了电抗器的可能破坏模式,进一步计算了电抗器的地震易损性曲线。研究结果表明:电抗器的动力特性近似于单自由度体系,一阶自振频率为3.3 Hz,阻尼比为3.9%;电抗器在地震作用下的变形主要发生在绝缘子以及绝缘子-线圈连接部位,上部线圈可认为是刚体;与绝缘子相比,绝缘子-线圈连接部位的刚度较小,变形更集中,是电抗器的薄弱部位;0.15g人工地震动试验后,电抗器自振频率下降3.6%,0.5g人工地震动试验后,电抗器自振频率下降6.3%;根据绝缘子实测应变,考虑地震作用与其他荷载产生的总应力,电抗器的安全系数为2.14,仍然具有一定的安全储备;基于试验结果计算电抗器的地震易损性,抗震能力中值为0.965g,对数标准差为0.4。 展开更多
关键词 干式电抗器 振动台试验 动力特性 抗震性能 变形模式 易损性曲线
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测试图形程序的进一步研究:PATTERN抽象及再实现 被引量:1
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作者 孙育宁 时万春 《计算机研究与发展》 EI CSCD 北大核心 1996年第11期842-848,共7页
异构自动测试仪(ATE)之间的测试图形程序移植是一项难度很高的工作。通常采用的方法是对测试图形向量进行逐条直移。这样,如果在异构ATE测试图形语言之间找不到对应的语言成分,将导致实际有可能成功的移植失败。并且,即使这... 异构自动测试仪(ATE)之间的测试图形程序移植是一项难度很高的工作。通常采用的方法是对测试图形向量进行逐条直移。这样,如果在异构ATE测试图形语言之间找不到对应的语言成分,将导致实际有可能成功的移植失败。并且,即使这样移植成功,移植的测试图形程序可保证词法和语法的正确性,但在大多数情况下,这些程序仍不能在目标ATE上正确运行。本文在详细分析了传统移植方法后,提出一种基于异构ATE功能对等的移植方法,使测试图形程序在移植前后保持其意义的一致性。利用这种方法,可以大大提高测试图程序的可移植性。 展开更多
关键词 软件工程 测试图形程序 程序移植
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Dependence of single event upsets sensitivity of low energy proton on test factors in 65 nm SRAM 被引量:1
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作者 罗尹虹 张凤祁 +2 位作者 潘霄宇 郭红霞 王圆明 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期566-571,共6页
In order to accurately predict the single event upsets (SEU) rate of on-orbit proton, the influence of the proton energy distribution, incident angle, supply voltage, and test pattern on the height, width, and posit... In order to accurately predict the single event upsets (SEU) rate of on-orbit proton, the influence of the proton energy distribution, incident angle, supply voltage, and test pattern on the height, width, and position of SEU peak of low energy protons (LEP) in 65 nm static random access memory (SRAM) are quantitatively evaluated and analyzed based on LEP testing data and Monte Carlo simulation. The results show that different initial proton energies used to degrade the beam energy will bring about the difference in the energy distribution of average proton energy at the surface and sensitive region of the device under test (DUT), which further leads to significant differences including the height of SEU peak and the threshold energy of SEU. Using the lowest initial proton energy is extremely important for SEU testing with low energy protons. The proton energy corresponding to the SEU peak shifts to higher average proton energies with the increase of the tilt angle, and the SEU peaks also increase significantly. The reduction of supply voltage lowers the critical charge of SEU, leading to the increase of LEP SEU cross section. For standard 6-transitor SRAM with bit-interleaving technology, SEU peak does not show clear dependence on three test patterns of logical checkerboard 55H, all" 1", and all "0". It should be noted that all the SEUs in 65 nm SRAM are single cell upset in LEP testing due to proton's low linear energy transfer (LET) value. 展开更多
关键词 low energy proton energy distribution tilt angle supply voltage test pattern
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1966—2018年岷江流域极端气温事件时空变化特征
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作者 郭为 李晓兵 +5 位作者 张鹏 刘清园 张志昊 王庆丰 梁瑞峰 李克锋 《水利水电技术(中英文)》 北大核心 2024年第S01期11-21,共11页
在全球变暖背景下,极端气候事件问题逐渐显著,岷江流域作为川滇生态屏障区的重要组成部分,受气候变化的影响较大,研究该流域极端气候事件时空变化规律,能为未来气象灾害防治等提供科学依据。基于1966—2018年岷江流域62个气象站点的气... 在全球变暖背景下,极端气候事件问题逐渐显著,岷江流域作为川滇生态屏障区的重要组成部分,受气候变化的影响较大,研究该流域极端气候事件时空变化规律,能为未来气象灾害防治等提供科学依据。基于1966—2018年岷江流域62个气象站点的气温资料,选用“气候变化检测和指标”专家组所确定的16个极端气温指数,采用一元回归方程、Sen斜率、反距离权重空间插值法和Mann-Kendall检验法分析极端气温指数的时空变化规律。结果显示:岷江流域极端气温事件存在明显的时间变化特征,并且变化趋势在空间分布上存在一定的差异性。结果表明:(1)岷江流域极端高温事件显著增加,极端低温事件显著减少;极端气温指数的突变年份主要集中在1990—2000年左右,其中极端低温指数均在突变后呈现显著下降趋势,极端高温指数、极值指数、其他指数中除了日较差指数,均在突变后呈显著上升趋势;(2)极端低温指数在流域内大部分地区呈下降趋势,平均年变化率为-0.98 d·(10a)^(-1);极端高温指数、极值指数和作物生长期指数大部分地区呈上升趋势,其中极端高温指数上升趋势在流域内呈西低东高的分布,作物生长期指数在流域内呈北高南低的分布;日较差指数在流域上游地区呈下降趋势,中下游地区呈上升趋势。 展开更多
关键词 极端气温事件 变化规律 M-K检验 指数 Sen斜率
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UHPC-NC组合箱梁顶板界面抗剪性能试验研究
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作者 程菊科 伍贤智 +1 位作者 杨树萍 罗晓光 《湘潭大学学报(自然科学版)》 CAS 2024年第2期123-130,共8页
为了研究超高性能混凝土(UHPC)与普通混凝土(NC)组合箱梁的界面抗剪性能,该文设计了3类界面处理方式不同的试件,分别为不处理类、凿毛类、涂缓凝剂+水冲洗类,同时进行了UHPC与NC的组合推出试验,分析3类试件的破坏形态和抗剪性能.试验结... 为了研究超高性能混凝土(UHPC)与普通混凝土(NC)组合箱梁的界面抗剪性能,该文设计了3类界面处理方式不同的试件,分别为不处理类、凿毛类、涂缓凝剂+水冲洗类,同时进行了UHPC与NC的组合推出试验,分析3类试件的破坏形态和抗剪性能.试验结果表明:UHPC与NC组合结构进行界面处理后,推出试件的破坏形态为普通混凝土侧的拔出破坏,与界面不处理的破坏形态相同,且各类试件的初始剪切刚度相近.但不同界面处理方式对试件的平均抗剪强度影响较大,进行界面处理后相较于不处理时的平均抗剪强度大幅提高,均为不处理时的4倍以上. 展开更多
关键词 超高性能混凝土 推出试验 界面破坏形态 组合顶板 抗剪性能
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逻辑内建自测试技术进展综述
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作者 金敏 向东 《集成技术》 2024年第1期44-61,共18页
逻辑内建自测试(logic buit-in self-test,LBIST)是一种可测试性设计技术,利用芯片、板级或系统上的部分电路测试数字逻辑电路本身。LBIST对于许多应用来说至关重要,尤其是国防、航空航天、自动驾驶等生命和任务关键型的应用。这些应用... 逻辑内建自测试(logic buit-in self-test,LBIST)是一种可测试性设计技术,利用芯片、板级或系统上的部分电路测试数字逻辑电路本身。LBIST对于许多应用来说至关重要,尤其是国防、航空航天、自动驾驶等生命和任务关键型的应用。这些应用需要执行片上、板上或系统内自检,以提高整个系统的可靠性及执行远程诊断的能力。该文首先给出了常用的LBIST分类,并描述了经典的,也是工业界应用最成功的LBIST架构——使用多输入特征寄存器和并行移位序列产生器的自测试架构;其次,对国内外研究团队、研究进展进行了总结;再次,详细剖析了LBIST的基本原理、时序控制、确定性自测试设计、低功耗设计、“X”容忍等关键技术点,列举出了主流的LBIST商业工具,并逐一分析了其软件架构和技术特点;最后,讨论当前LBIST技术仍需进一步解决的问题,并进行展望。 展开更多
关键词 逻辑内建自测试 伪随机序列产生器 多输入特征寄存器 确定性自测试 可测试性设计
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非对称运行西河泵站前池试验分析
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作者 徐鹏飞 陈业超 +2 位作者 徐贵颖 张丽娟 杨帆 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第2期409-416,共8页
为明确西河泵站非对称机组运行时前池的流态特征,基于物理模型试验的方法对西河泵站的前池及进水流道进行整体物理模型试验,共获取4种不同开机方案时西河泵站前池的流场和速度分布规律,并采用计算流体动力学技术对最低水位时8台机组全... 为明确西河泵站非对称机组运行时前池的流态特征,基于物理模型试验的方法对西河泵站的前池及进水流道进行整体物理模型试验,共获取4种不同开机方案时西河泵站前池的流场和速度分布规律,并采用计算流体动力学技术对最低水位时8台机组全开的方案进行数值分析。结果表明:在0.75负荷排涝时,非对称机组运行方案2的前池两侧有微弱旋流,开机方案3和开机方案4前池流态均平稳,开机方案3泵站进口断面的底流速分布均匀度为78.2%;推荐两侧边机组和中间机组各2台开机运行;在全负荷排涝流量且最低水位时,机组全开时两边机组流道进口的水力性能指标最低,在实际运行时应注意两侧边机组运行的安全稳定性。研究成果可为西河泵站的实际运行管理提供一定的参考。 展开更多
关键词 西河泵站 前池 流态 开机方案 模型试验
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三轴剪切条件下水泥胶结砂声发射特征信息演化规律研究
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作者 刘昂 张尔康 林文丽 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期618-627,共10页
结合声发射(AE)传感装置开展考虑水泥掺入比、围压等条件的水泥胶结砂排水三轴试验。研究结果表明:水泥胶结砂的AE特征信息演化规律与应力-应变曲线具有较好的对应性;累计AE事件随水泥掺入比的增大而减小,这与水化物的增加抑制了砂颗粒... 结合声发射(AE)传感装置开展考虑水泥掺入比、围压等条件的水泥胶结砂排水三轴试验。研究结果表明:水泥胶结砂的AE特征信息演化规律与应力-应变曲线具有较好的对应性;累计AE事件随水泥掺入比的增大而减小,这与水化物的增加抑制了砂颗粒间滑移密切相关;随围压增大,累计AE事件增大,同时促进了AE信号在介质中的传播和胶结的断裂;随着水泥掺入比增加、围压降低,水泥胶结砂破坏形态由鼓胀破坏逐渐向剪切带破坏过渡。 展开更多
关键词 声发射 水泥胶结砂 水泥掺入比 三轴剪切 破坏模式
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交通荷载作用下黄土地基土压力分布规律研究
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作者 刘明 《山西建筑》 2024年第10期72-75,79,共5页
为研究交通荷载作用下黄土地基土压力分布规律,基于某埋地管道项目现场试验,采用重载卡车以不同载重及低速工况下测得地基竖向和横向的动土压力。研究表明:在车辆荷载作用下竖向土压力随深度减小,且越深影响程度越小;动土压力沿竖向传... 为研究交通荷载作用下黄土地基土压力分布规律,基于某埋地管道项目现场试验,采用重载卡车以不同载重及低速工况下测得地基竖向和横向的动土压力。研究表明:在车辆荷载作用下竖向土压力随深度减小,且越深影响程度越小;动土压力沿竖向传递的能力大于沿横向传递的能力;轴载产生的动应力峰值随着地基深度的增加逐渐减小且具有滞后性。车辆在低速10km/h~30km/h区间内,速度对地基的动力效应影响不太显著。 展开更多
关键词 交通荷载 动土压力 现场试验 分布规律
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Comparative Study on Physical Fitness Test Models of Chinese, Japanese and American Students
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作者 Xingxing Hou 《教育研究前沿(中英文版)》 2019年第4期309-312,共4页
The physical health of adolescents is related to the future of the nation and the competitiveness of the country.Through a comparative analysis of the backgrounds,organizations,testing programs and evolution processes... The physical health of adolescents is related to the future of the nation and the competitiveness of the country.Through a comparative analysis of the backgrounds,organizations,testing programs and evolution processes of physical health tests in China,Japan and the United States,the three countries are explored.The development trends and problems of student physical fitness tests,find the differences,learn about the research results and experiences of physical fitness tests in Japan and the United States,draw on Japanese and American management models and successful cases,and propose some methods to optimize and improve China's physical fitness test models.It is recommended to make full use of the existing resources to promote the improvement of students'physical fitness. 展开更多
关键词 CHINESE JAPANESE AMERICAN STUDENTS PHYSIQUE test pattern Contrastive Study
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