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人工神经网络在镀锌钢板点焊性能估测中的应用 被引量:7
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作者 王宸煜 王敏 董溯攀 《上海交通大学学报》 EI CAS CSCD 北大核心 2001年第3期420-423,共4页
将人工神经网络引入镀锌钢板点焊的质量预测中 ,将实验得到的大量点焊规范参数与相应点焊接头质量的试验数据提供给神经网络学习 ,通过其非线性映射的泛化能力自动抽取所学习知识的特征 ,描述点焊规范参数空间与焊点接头质量空间的映射... 将人工神经网络引入镀锌钢板点焊的质量预测中 ,将实验得到的大量点焊规范参数与相应点焊接头质量的试验数据提供给神经网络学习 ,通过其非线性映射的泛化能力自动抽取所学习知识的特征 ,描述点焊规范参数空间与焊点接头质量空间的映射关系 .结果表明 ,学习后的神经网络的预测曲线能够合理地预测焊接电流对镀锌钢板点焊的焊点熔核直径与拉剪强度的影响规律 ,恰当地反映点焊的基本原理 ,说明人工神经网络在镀锌板点焊性能估测中的应用是可行的 . 展开更多
关键词 人工神经网络 镀锌钢板 点焊 接头质量 熔核 性能估测
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放养蛋鸡营养需要与生产性能估测
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作者 范京辉 《杭州农业与科技》 2010年第2期35-37,共3页
在林地、冬闲田放养蛋鸡生产土鸡蛋,是近年新兴的养殖模式。此模式使林地资源得到有效利用,而且,土鸡蛋质优价高,为饲养者带来可观经济效益。
关键词 蛋鸡生产 性能估测 营养需要 放养 林地资源 养殖模式 有效利用 经济效益
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提高奶牛饲养效果的方法
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作者 裴桂秋 王飞 包玉玺 《养殖技术顾问》 2010年第12期1-1,共1页
1选购优良品种尽量选购正规奶牛场饲养的奶牛,并索要及查看奶牛档案,逐头细致地进行奶牛体质外貌鉴定,健康检查,生产性能估测,妊娠诊断,疫病检疫。购买奶牛时应符合优良奶牛的外貌特征,其毛色呈黑白花,花片分明。体躯长、宽、深,背腰结... 1选购优良品种尽量选购正规奶牛场饲养的奶牛,并索要及查看奶牛档案,逐头细致地进行奶牛体质外貌鉴定,健康检查,生产性能估测,妊娠诊断,疫病检疫。购买奶牛时应符合优良奶牛的外貌特征,其毛色呈黑白花,花片分明。体躯长、宽、深,背腰结合良好,尻长、平、宽,胸部发育良好。乳房大,乳腺发育充分,乳头大小适中,乳静脉粗大而弯曲,乳井大而深。 展开更多
关键词 饲养效果 奶牛场 外貌鉴定 乳腺发育 优良品种 健康检查 性能估测 妊娠诊断
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Pseudo-Dynamic Testing for Seismic Performance Assessment of Buildings with Seismic Isolation System Using Scrap Tire Rubber Pad Isolators 被引量:6
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作者 Huma Kanta Mishra Akira Igarashi +1 位作者 Dang Ji Hiroshi Matsushima 《Journal of Civil Engineering and Architecture》 2014年第1期73-88,共16页
Investigation of seismic performance of buildings with STRP (scrap tire rubber pad) seismic isolators by means of pseudo-dynamic tests and numerical simulation is presented. The isolated building is numerically mode... Investigation of seismic performance of buildings with STRP (scrap tire rubber pad) seismic isolators by means of pseudo-dynamic tests and numerical simulation is presented. The isolated building is numerically modeled, while the base isolation layer is considered as the experimental substructure in the pseudo-dynamic tests. The test result verifies that the STRP isolator shows acceptable shear deformation performance predicted by the design methods, and demonstrated that seismic isolation using STRP works as a protective measure to provide enhanced seismic performance of the building indicated by the reduction of top floor absolute acceleration, drift and base shear as designated. 展开更多
关键词 Pseudodynamic test STRP isolator numerical simulation base isolation seismic performance.
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Assessment of the Performance of WEPP in Purple Soil Area with Simulated Rainfall Experiments 被引量:3
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作者 FU Bin WANG Yukuan +1 位作者 XU Pei YAN Kun 《Journal of Mountain Science》 SCIE CSCD 2012年第4期570-579,共10页
The water erosion prediction project (WEPP) model is a popular water erosion prediction tool developed on the basis of the physical processes of water erosion. Although WEPP has been widely used around the world, it... The water erosion prediction project (WEPP) model is a popular water erosion prediction tool developed on the basis of the physical processes of water erosion. Although WEPP has been widely used around the world, its application in China is still insufficient. In this study, the performance of WEPP used to estimate the runoff and soil loss on purple soil (Calcaric Regosols in FAO taxonomy) sloping cropland was assessed with the data from runoff plots under simulated rainfall conditions. Based on measured soil properties, runoff and erosion parameters, namely effective hydraulic conductivity, inter-rill erodibility, rill erodibility, and critical shear stress were determined to be 2.68 mm h-1, 5.54 x l0^6 kg s-1 m-4, 0.027 s m-1 and 3-5 Pa, respectively, by using the recommended equations in the WEPP user manual. The simulated results were not good due to the low Nash efficiency of 0.41 for runoff and negative Nash efficiency for soil loss. After the four parameters were calibrated, WEPP performed better for soil loss prediction with a Nash efficiency of 0.76. The different results indicated that the equations recommended by WEPP to calculate parameters such as erodiblity and critical shear stress are not suitable for the purple soil areas, Sichuan Province, China. Although the predicted results can be accepted by optimizing the runoff and erosion parameters, more research related to the determination of erodibility and critical sheer stress must be conducted to improve the application of WEPP in the purple soil areas. 展开更多
关键词 WEPP Soil erosion Simulated rainfall Purple soil ERODIBILITY
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Experiences in using gas dispersion measurements to evaluate metallurgical performance of scavenger cleaner and recleaner circuit at Vale's Thompson Mill 被引量:1
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作者 刘洪均 张炜 孙春宝 《Journal of Central South University》 SCIE EI CAS 2014年第10期3955-3962,共8页
The performance of a flotation circuit is largely the result of the operator's response to visual clues. This includes manipulation of the gas input and how it is distributed to cells in a bank. A new gas dispersi... The performance of a flotation circuit is largely the result of the operator's response to visual clues. This includes manipulation of the gas input and how it is distributed to cells in a bank. A new gas dispersion technology was presented which was conducted to perform characterization tests in Outokumpu 30 m3 and 50 m3 flotation cells installed at Thompson Vale's concentrator, and subsequent data analysis. The experimental program was designed to establish "as-found" baseline conditions for each cell of the two-parallel banks in the scavenger-cleaner and recleaner circuit, to select and characterize one typical cell in the two banks with either different frother concentrations or different air flow rates, and establish what variables can be manipulated in future characterization work. A three-parameter model was developed in order to link the bubble size and frother concentration. This relationship can be used to correlate gas dispersion change to improved metallurgical performance. 展开更多
关键词 bubble size bubble size distribution bubble surface area flux gas dispersion
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Symmetry of cardiac function assessment 被引量:4
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作者 Xu-Fang BAI Amy X MA 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第6期517-520,共4页
Both right and left ventricles are developed from two adjacent segments of the primary heart tube. Though they are different with regard to shape and power, they mirror each other in terms of behavior. This is the fir... Both right and left ventricles are developed from two adjacent segments of the primary heart tube. Though they are different with regard to shape and power, they mirror each other in terms of behavior. This is the first level of symmetry in cardiac function assessment. Both cardiac muscle contraction and relaxation are active. This constructs the second level of symmetry in cardiac function assessment. Combination of the two levels will help to find some hidden indexes or approaches to evaluate cardiac function. In this article, four major indexes from echocardiography were analyzed under this principal, another seventeen indexes or measurement approaches came out of the shadow, which is very helpful in the assessment of cardiac function, especially for the right cardiac function and diastolic cardiac function. 展开更多
关键词 Cardiac function ECHOCARDIOGRAPHY SYMMETRY
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Performance assisted enhancement based on change point detection and Kalman filtering 被引量:1
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作者 任孝平 王健 +1 位作者 薛志超 谷明琴 《Journal of Central South University》 SCIE EI CAS 2013年第12期3528-3535,共8页
A performance assisted enhancement Kalman filtering algorithm(PAE-KF) for GPS/INS integration navigation in urban areas was presented in this work. The aim of this PAE-KF algorithm was to prevent "deep contaminat... A performance assisted enhancement Kalman filtering algorithm(PAE-KF) for GPS/INS integration navigation in urban areas was presented in this work. The aim of this PAE-KF algorithm was to prevent "deep contamination" caused by error GPS data. This filtering algorithm effectively combined fault estimation of raw GPS data and nonholonomic constraint of vehicle. In fault estimation, a change point detection algorithm based on abrupt change model was proposed. Statistical tool was then used to infer the future bound of GPS data, which can detect faults in GPS raw data. If any kinds of faults were detected, dead reckoning mechanism begins to compute current position. Nonholonomic constraint condition of vehicle was used to estimate velocity of vehicle and change point detection was added into classic Kalman filtering structure. Experiment on vehicle shows that even when the GPS signals are unavailable for a period of time, this method can also output high accuracy data. 展开更多
关键词 change point detection Kalman filtering nonholonomic constraint GPS/INS integrated navigation system
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Application of Non-destructive Testing to Evaluate the Performance of Bridges Structures
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作者 Diego Jesus de Souza Elaine Souza dos Santos +4 位作者 Eric Pianizolli Flor Gabriel Pereira Marinho Giovana Costa Reus Heloise Cristine Cezario Leticia Andrade Camara 《Journal of Civil Engineering and Architecture》 2017年第1期1-7,共7页
Bridges are important elements in road system and can influence the entire economy of cities and region. Usually, these structures have high financial investments for their constructions, in this way, maintenance and ... Bridges are important elements in road system and can influence the entire economy of cities and region. Usually, these structures have high financial investments for their constructions, in this way, maintenance and conservation become so important. Inspection is a technical activity that covers several operations, including performance analysis; examination; final performance report, other operations may be necessary, such as maintenance work, recovery, strengthening and rehabilitation. Technical examination together with some test methods allows a critical and parametric judgment of the bridge performance by minimizing the subjectivity of visual evaluations, and permits a more detailed diagnosis. This paper discusses the methodology to perform tests to complement the assessment recommended by DNIT (Brazilian National Department of Transport Infrastructure), which consists only on a visual judgment. This approach provides technical basis to classify the bridges as its need and urgency of maintenance. 展开更多
关键词 Non-destructive testing BRIDGES concrete durability.
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Attack Resistant Trust Management Model Based on Beta Function for Distributed Routing in Internet of Things 被引量:1
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作者 Dong Ping Guan Jianfeng +1 位作者 Xue Xiaoping Wang Hongchao 《China Communications》 SCIE CSCD 2012年第4期89-98,共10页
With the rapid development of Internet of Things (IoT),the issue of trust in distributed routing systems has attracted more research attention.The existing trust management frameworks,however,suffer from some possible... With the rapid development of Internet of Things (IoT),the issue of trust in distributed routing systems has attracted more research attention.The existing trust management frameworks,however,suffer from some possible attacks in hostile environments,such as false accusation,collusion,on-off,and conflicting behavior.Therefore,more comprehensive models should be proposed to predict the trust level of nodes on potential routes more precisely,and to defeat several kinds of possible attacks.This paper makes an attempt to design an attack-resistant trust management model based on beta function for distributed routing strategy in IoT.Our model can evaluate and propagate reputation in distributed routing systems.We first describe possible attacks on existing systems.Our model is then proposed to establish reliable trust relations between self-organized nodes and defeat possible attacks in distributed routing systems.We also propose a theoretical basis and skeleton of our model.Finally,some performance evaluations and security analyses are provided to show the effectiveness and robustness of our model compared with the existing systems. 展开更多
关键词 trust management IOT distributed ROUTING PROBABILITY
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A novel SINR and mutual information based radar jamming technique 被引量:2
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作者 王璐璐 王宏强 +1 位作者 程永强 秦玉亮 《Journal of Central South University》 SCIE EI CAS 2013年第12期3471-3480,共10页
The improvements of anti-jamming performance of modem radar seeker are great threats to military targets. To protect the target from detection and estimation, the novel signal-to-interference-plus-noise ratio (SINR)... The improvements of anti-jamming performance of modem radar seeker are great threats to military targets. To protect the target from detection and estimation, the novel signal-to-interference-plus-noise ratio (SINR)-based and mutual information (Ml)-based jamming design techniques were proposed. To interfere with the target detection, the jamming was designed to minimize the S1NR of the radar seeker. To impair the estimation performance, the mutual information between the radar echo and the random target impulse response was used as the criterion. The spectral of optimal jamming under the two criteria were achieved with the power constraints. Simulation results show the effectiveness of the jamming techniques. SINR and MI of the SINR-based jamming, the MI-based jamming as well as the predefined jamming under the same power constraints were compared. Furthermore, the probability of detection and minimum mean-square error (MMSE) were also utilized to validate the jamming performance. Under the jamming power constraint of I W, the relative decrease of the probability of detection using S1NR-based optimal jamming is about 47%, and the relative increase of MMSE using Ml-based optimal jamming is about 8%. Besides, two useful jamming design principles are concluded which can be used in limited jamming power situations. 展开更多
关键词 detection jamming mutual information (MI) parameter estimation minimum mean-square error (MMSE) probabilityof detection signal-to-interference-plus-noise ratio (SINR)
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Investigation of Key Parameters for 3-D Dredging Plume Model Validation
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作者 Junsheng Jiang 《Journal of Shipping and Ocean Engineering》 2014年第5期129-139,共11页
Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental... Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental impact assessment of the proposed dredging, particularly those associated with suspended sediments and sedimentation. Model validation and performance are still not resolved because of the difficulty of site measurements and the understanding of the parameters used in the model. This paper presents a 3-D dredging plume model based on the MIKE3 software package to investigate parameters which affect the model performances. As a result of lack of site data for the public domain uses, the model scenarios are designed artificially for sensitive runs to identify the key parameters affecting plume behaviours. The factors include dredging spill rates using different dredging methods, equipment and sediment settling velocities. The influence of wave and wind effects combined with tidal forces on the sediment re-suspended rates and the advection/dispersion scales are also assessed. 展开更多
关键词 3-D dredging plume model settling velocity sediment measurement.
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Bridging the Achievement Gap for Students: A Blueprint for Success
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作者 Kirk Gavin Rose Campbell Seward Hamilton 《Journal of Literature and Art Studies》 2016年第8期979-987,共9页
The purpose of this research is to identify and examine the achievement gaps between students. Over the past thirty years, emphasis has been placed on achievement levels of students in this country. State test results... The purpose of this research is to identify and examine the achievement gaps between students. Over the past thirty years, emphasis has been placed on achievement levels of students in this country. State test results, SAT Scores, ACT scores and other assessment instruments have been used to determine performance standards and test results for students. Data analyzed for White students compared to African American and Hispanic students have provided critical information in identifying academic progress and skill deficits for all students. This article will highlight some of the achievement gaps which exit among White, African American and Hispanic Students. Recommendations will also be emphasized to help improve student achievement levels in an effort to close the achievement gap. 展开更多
关键词 student achievement achievement gap comparative achievement levels
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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