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Decadal variations of the relationship between the summer North Atlantic Oscillation and middle East Asian air temperature

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Decadal variations of the relationship between the summer No...

DEVELOPMENT OF STEP-POOL SEQUENCE AND ITS EFFECTS IN RESISTANCE AND STREAM BED STABILITY

作者： Jianqi Sun,Huijun Wang,and Wei Yuan 1 Nansen-Zhu International Research centre(NZC),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijmg,china. 2 china Meteorological {3. training centre,Beijmg,china.

[1]The relationship between the summer(July-September) North Atlantic Oscillation (SNAO) and simultaneous East Asian air temperature is *** results show that the SNAO is related to middle East Asian summer air temperature,however this linkage varies with time on decadal timescale:a strong connection appears after the late 1970s but a weak connection before the late *** analysis indicates that this instable relationship may have resulted from the shift of the SNAO mode around the late *** the period of 1979-2003.the centers of the SNAO mode are located more eastward.A positive-phase(negative-phase) SNAO produces a strong lower-level divergence(convergence) over the Asian jet entrance region,in turn stimulates a strong upper-level convergence(divergence) via the Ekman *** a convergence (divergence) then excites a zonally oriented quasi-stationary barotropical Rossby wave train along the Asian upper-level *** the SNAO signal is transported eastward to East Asia,resulting in an anomalous summer air temperature over middle East Asia. However,in the period of 1951-1975,the centers of the SNAO mode are located more *** associated upper-level divergence/convergence is away from the Asian jet entrance region,and the SNAO signal cannot be transported eastward to East *** the connection is broken.

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International Journal of Sediment Research 2004年第3期19卷 161-171页

作者： Zhao-Yin WANG, Jiang XU and Changzhi LI Professor, Dept. of Hydraulic Engineering, Tsinghua University, beijing & Chairman of Advisory Council, International Research and training Center on Erosion and Sedimentation, 100084, china, Email: zywang@***.M. Phil., Dr. & Post Doctorate research fellow, Dept. of Hydraulic Engineering, Tsinghua University, beijing, 100084, china Dept. of Hydraulic Engineering Tsinghua University Beijing & Chairman of Advisory Council International Research and Training Center on Erosion and Sedimentation 100084 China Dr. & Post Doctorate research fellow Dept. of Hydraulic Engineering Tsinghua University Beijing 100084 China

Experiments were conducted and field investigations were performed to study the development of step-pool sequence and its effects on resistance to the flow and stream bed stability. Step-pool sequence develops in incised channels as a result of streambed erosion, which is compared with sand dunes and armor layer of the role in resistance and streambed protection. The tight interlocking of particles in steps gives them an inherent stability which only extreme floods are likely to disturb. That stability suggests that step-pools are a valid equilibrium form, especially when coupled with their apparent regularity form and their role in satisfying the extreme condition of resistance maximization. The development degree of step-pools, SP, is proportional to the streambed slope. If the incoming sediment load is equal to or more than the sediment-carrying capacity of the flow, there is no bed erosion and thence there are no step-pools. If the flow depth increases and is over the step-height the resistance caus

关键词： Step-pool Streambed stability Erosion Resistance Rate of energy dissipation Manning’s roughness n

A systematic method based on statistical pattern recognition for estimating product quality on-line

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Journal of University of Science and Technology beijing 2003年第1期10卷 69-73页

作者： Guang Li, Huade Li, Shaoyuan Sun, and Zhengguang XuInformation Engineering School, University of Science and Technology beijing, beijing 100083. china Information Engineering School University of Science and Technology Beijing Beijing 100083 China

To avoid the complexity of building mechanistic models by studying the inner nature of the object, a systematic method based on statistical pattern recognition is developed in order to estimate the product quality on-line. The mapping relationship between a feature space and a product quality space can be built by using regression analysis, and in applying clustering analysis the product quality space can be partitioned automatically. Eventually, estimating product quality on-line can be accomplished by sorting the mapped data in the partitioned quality space. A concrete problem is proposed which has a relatively small ratio of training data to input variables. By implementing the method mentioned above, a satisfying result has been achieved. Furthermore, the further question about choosing suitable mapping methods is briefly discussed.

关键词： pattern recognition regression analysis clustering analysis ISODATA algorithm sorting algorithm

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地热水源热泵技术应用市场前景

太阳能学报 2002年第6期23卷 692-695页

作者：朱家玲苗常海董志林洪庆华天津大学地热研究培训中心天津300072 天津市塘沽区地热试验研究中心天津300072 天津大学建工学院天津300072

该文描述了利用水源热泵技术的直接、间接经济效益和环境效益 ;并针对水源热泵设备的类型及供暖规模适用范围进行了优化设计 ;

关键词：地热水源热泵技术市场前景环境经济性

A Study of Spiral Tap with Large Diameter

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厦门大学学报（自然科学版） 2002年第S1期41卷 134-135页

作者： LI Lin 1, LI Da-wei 1, CHAI De-ming 2 (1. Tianjin Chinese-German Vocational training Center, Tianjin 3.0191 , china 2. The Experimental Eanipent-Making Factory under Physical Chemistry Academy Spiral, Tianjin 3.0180, china)

The design and manufacture of spiral tap yet are in r esearch stage at present. This paper mainly introduces how to calculate its geom etric parameters and scientific selection of them with vector method. In additio n, an empiric formula of the tool life of spiral tap with large diameter is esta blished by method of correlation. The practice of design, manufacture and applying proves the advantage of spiral tap by the comparison between the spiral tap and common tap with same size. In the application of spiral tap has got better economic effect. The cutting fea ture and economic effect are obvious, that mean spiral tap greatly better than c ommon tap. The bright and wide prospect are going to come. No greatly increasing the ω can be effective to improve the cutting condition. Scientific selection of cutting speed V can increase the tool life of tapping and life of tapping too l.

关键词： spiral tap large diameter service life durabil ity formula

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石油化工安全仿真技术及应用

系统仿真学报 2003年第10期15卷 1356-1359,1363页

作者：牟善军姜春明吴重光中国海洋大学海洋工程学院中国石油化工股份有限公司安全工程研究院青岛266071 中国石油化工股份有限公司安全工程研究院北京化工大学信息科学与技术学院

安全模拟与安全仿真学是安全科学技术的重要学科分支。随着信息技术和计算机技术的发展,仿真技术在石油化工安全评价、安全监测、安全控制与安全训练等多领域多层面,正在或即将发挥着越来越大的作用。目前,仿真技术已成功地应用于揭示... 详细信息

安全模拟与安全仿真学是安全科学技术的重要学科分支。随着信息技术和计算机技术的发展,仿真技术在石油化工安全评价、安全监测、安全控制与安全训练等多领域多层面,正在或即将发挥着越来越大的作用。目前,仿真技术已成功地应用于揭示工艺过程内在危险;设备结构疲劳分析;毒物泄漏、扩散、爆炸、燃烧三维可视化分析;故障识别与诊断;辅助安全训练。仿真技术已成为系统安全工程中的关键技术之一。

关键词：石油化工过程安全仿真安全评价故障诊断仿真训练

SHRINKAGE OF THE ESTUARINE CHANNELS OF THEHAIHE DRAINAGE SYSTEM AND ITS INFLUENCES ON FLOOD HAZARD

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International Journal of Sediment Research 1999年第2期14卷 65-76页

作者： HU Shixiong WANG Zhaoyin and DING Pingxing (International Research and training Center of Erosion and Sediment, P.O.Box 3.6, beijing 100044, china) (The State Key Laboratory of Estuarine and Coastal Research, East china Normal University, Shanghai, 20

The reductions of runoff and sediment load in the Haihe River Basin and the causes of the shrinkage of the estuarine channels are analyzed in this paper it is concluded that the modern Yellow River sediment can be transported to the south part of the Bohai Bay, but rarely to the north part and the Tianjin Harbor. Sediment from the mid of the Bohai Bay does not affect the estuarine channels. The sediment caused the estuarine channels shrinkage are from the modern and ancient Yellow and the Haihe River deposit removed by wave. tidal current, and beach erosion. The influences of the estuary shrinkage on the flood discharge capacity of the river mouth channels and the flood hazard are discussed. The maximum capacity of the reservoirs and pools is about 20 billion m3.n the south part of the basin while the capacity in the north part is only 7.5 billion m3. Two 100 years floods occurred in the watershed in 1963.and in1996 with total runoff about 3. billion m3.ach. The economic loss in 1996 is about $6 billion, nearly two times of that in 1963.in the south part of the area. One of the main reasons is that the discharge capacity of the channels in the area had reduced by 50%. If another 100 years flood occurs in the south part again, the economic loss will be similar to that in 1996. If a 100 years flood occurs in the north part, the economic loss will be much higher than that in 1996. Because the storage capacity of reservoirs and pools in the area is much less than that in the south area. and discharge capacities of the north estuarine channels decreased more sharply than that of the south. Strategies for controlling estuary shrinkage are suggested. Physical and mathematical models show that trailer dredging combined with scouring with runoff or tidal water is economical and practical. Guiding dikes at the river mouths to prevent turbidity water entering into the estuarine channel will be a major strategy. Building a new gate combining the harbor may also mitigate the sed

关键词： Shrinkage of the estuarine channel the Haihe Drainage System Flood hazard

Application of a Adaptive-Learning Situation Evaluation Function Based on Feature-Matrix in Dots-and-Boxes

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Application of a Adaptive-Learning Situation Evaluation Func...

Prediction of Mechanical Properties of 50CrVA Tempered Steel Strip for Horn Diaphragm Based on BPANN

第24届中国控制与决策会议

作者： Hang YIN 1. Engineering training center 2. Shenyang Aerospace University 3. Shenyang, china Hang YIN, Guiran CHANG, Xingwei WANG 1. School of Information Science and Engineering 2. Northeastern University 3. Shenyang, china

this paper proposes a method for obtaining a reasonably accurate evaluation function of a game situation through the data of games and the situation feature matrix. An accurate evaluation function is indispensable for a strong computer game program. A game situation is projected into a feature matrix which consists of feature variates charactering the situation. Using variates as input and employ a multi-layer perception as a nonlinear evaluation function. Since it is not easy to obtain accurate evaluated values of situations, the reinforcement adaptive-learning is employed. Experiments using 13. games show that the proposed method works well in obtaining a very accurate evaluation function for Dots-and-Boxes.

关键词： computer games adaptive-learning situation feature-matrix evaluation function

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Journal of Wuhan University of Technology(Materials Science) 2009年第5期24卷 791-795页

作者：江树勇 Engineering training Center Harbin Engineering University

50CrVA cold-rolled spring steel strip was used to fabricate the diaphragm of the automotive horn. The material parameters which were taken into account in the design of the dia-phragm involve elongation, elastic limit, Young＇s modulus, yield strength and tensile strength. The tempering process was carried out in order to enable the diaphragm to possess the excellent mechanical properties, such as high elastic limit, high fatigue strength and perfect stress relaxation resistance. As a nonlinear information processing system, the backpropagation artificial neural network （BPANN） was applied to predict and simulate the relationship between the mechanical properties of the diaphragm and the tempering process parameters. Experimental results show that a BPANN with 3.8-5 architec-ture is capable of predicting the relationship between the mechanical properties of the diaphragm and the tempering temperature successfully and lays the profound foundations for optimizing the design of the diaphragm. BPANN simulation results show that the tempering temperature ranging from 3.0 to 420 ℃ contributes to enhancing the comprehensive mechanical properties of the diaphragm including high Young＇s modulus, high elastic limit and high fatigue strength.

关键词： artificial neural networks mechanical properties tempering diaphragm 50CrVA