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Convolution Estimates and Model Surfaces of Low Codimension


Raw materials, secondary material consumption, energy consumption, and environment impacts of process planning were optimized to improve the green attribute of process planning of parts with the supports of the databases and model repositories.


Based on the methodology of a study on water, soil environmental capacity, and mass conservation theory in a system, the concept and model on sediment environmental capacity for 137Cs in Daya Bay were developed.


Examples of applied use of peroxidasecatalyzed enzyme and model systems are given (oxidation of organic compounds, chemical analysis, enzyme immunoassay, tests for antioxidant activity of biological fluids).


All studied glycosides did not affect the cell and model lipid membranes.

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 This paper discusses some problems which are found to be important in designing the arch dam of the LivHsiHohydroelectrical power station. The arch dam under discussion has a max. height of 82 m and spans 255. m, situated in a Vshaped valley. It is an overflow arch dam of the various radius and thickness type. The technical design has been nearly finished and the dam is now under construction. The first problem discussed is the investigation of the stability of arch dam under various ioads when the dam... This paper discusses some problems which are found to be important in designing the arch dam of the LivHsiHohydroelectrical power station. The arch dam under discussion has a max. height of 82 m and spans 255. m, situated in a Vshaped valley. It is an overflow arch dam of the various radius and thickness type. The technical design has been nearly finished and the dam is now under construction. The first problem discussed is the investigation of the stability of arch dam under various ioads when the dam is rested on a rock foundation with unexpected jointe and cracks. Methods and formulas for the determination of stability factors are recommended. Then the paper reviews the various methods of stress andlysis of arch dams now in use and finds that the cantileverarch method (or so called the trial load method) is a suitable one. An amphified procedure is suggested, with this procedure and by means of certain tables of founda tion and arch deformation constanis, the analysis of stressos and deflections of a circular arch including the effect of foundation deformation can be simplified greately without sacrifyinq dccuracy. The necessdry tables needed in analysis will be presented in an dnother paper. The problems of temperature control and temperature stresses determination are also impor lant ones in arch dam design and construction. This paper discusses the vdrious principles of temperature control and method of computation, and describes the one accepted in this dam. The priciples of analysis of temperature stresses of arch dams are discussed in detail. Finally the problem of discharginq floods over the arch dam is described in brief. The design work in this respect has not been finished, further investigations and model tests are roquired.  本文旨在论述流溪河拱壩工程在设计中一些主要问题。拱壩最大壩高82公尺,壩顶弧长255.5公尺,位于一V形山谷中。壩体大不同半径和厚度拱壩并采用壩顶溢流形式。工程设计及施工已接近完成。本文首先探讨了拱壩壩头岩基具有节理和裂隙时在不同荷载下的稳定问题。推荐了决定系数的方法和公式。其后就现有的拱壩各种放力分析方法进行了论述并认力悬臂拱法(或称试载法)较为适用。本文对于试载法提出了改进步骤,利用这些改进步骤并借用一定数量的基础和拱圈变形常数表则计算应力分析和包括基础变形的圆拱变位可大大简化并无损其精度。在分析中所需数表将另著文介绍。控制拱壩温度和确定温度应力问题在拱壩设计和施工中也极关重要。本文论述了温度控制的各种原理和计算方法,并描述了本工程所采用的措施。对于拱壩温度应力的分析原理曾加论述。最后曾就拱壩壩顶溢流问题加以简述。有关此项新颖问题的设计,需待进一步研究并进行模型试验。  This paper deals with the problem of energy dissipation of high overflow dam with flip bucket and the estimation of downstream local erosion. Besides the kinetic energy carried away by the tailwater flow, the three ways of energy dissipation, i.e. (1) along the surface of overflow dam, (2) within the trajectory of jet and (3) in the effected water cushion, are discussed firstly. Thereby, the amount of energy, △E_(34), dissipated in the water cushion composed of the tailwater and the scour pit eroded by the... This paper deals with the problem of energy dissipation of high overflow dam with flip bucket and the estimation of downstream local erosion. Besides the kinetic energy carried away by the tailwater flow, the three ways of energy dissipation, i.e. (1) along the surface of overflow dam, (2) within the trajectory of jet and (3) in the effected water cushion, are discussed firstly. Thereby, the amount of energy, △E_(34), dissipated in the water cushion composed of the tailwater and the scour pit eroded by the fallen jet is estimated. By knowing the rate of energy dissipation per unit volume of the water cushion, η, the volume of water cushion to fulfill the requirement of energy dissipation is obtained as V=△E_(34)/η. Furthermore, the maximum depth of water cushion, T, is determined from the relationship between V and T. Since η is proportional to H~(1/2), so the expression of T obtained by the above procedure is T=K_3q~(0.5)H~(0.25). In the stage of planning and preliminary design, K_3 may be considered as 1.25 for the quick estimation of local erosion. Prototype observation and model test data of erosion pit of eight overflow dams are compared with the corresponding estimated erosion depth, and their basic agreement is acquired. In the another part of this paper, the horizontal distance of trajectory is discussed. It indicates that the elevation of flip bucket plays important role as well as the lip angle of the bucket. So that, the lip angle of the bucket corresponding to the maximum trajectory distance is usually less than 45°. The rear slope of the erosion pit is used as the criterion of the effect of local erosion against the stability of dam, and the critical value of this slope is suggested.  本文首先探討了湛流高坝采用鼻坎挑流泊能的各段能量損失,估計射流在水垫中所消失的能量。其次,推导得水垫的单位体积消能率約式,求得滿足消能要求的水垫体积。再次,根据水垫的几何形状,得出估計水垫內最大水深的算式。文中并給出冲刷深度估算公式的諾模图。此外,还探討了鼻坎高程对射程的影响,提出相应于最大射程的仰角小于45°;并从冲刷坑的后坡来探討冲刷坑对建筑物安全的影响。最后,根据十二点原型观测和模型試驗資料,对提出的冲刷深度估算約式进行了核驗比較。  This paper presents the results of waveresistance calculations and model experiments on a seagoing catamaran which had a conventional form with prismatic coefficient 0.645.The waveresistauce of a catamaran ship is composed of two parts: the waveresistance due to each hull itself and that arising from the mutual action between the two hulls.It is then derived that the resistance of catamarans should be the functions of ship form, Froude number and separationlength ratio. A series of computations based... This paper presents the results of waveresistance calculations and model experiments on a seagoing catamaran which had a conventional form with prismatic coefficient 0.645.The waveresistauce of a catamaran ship is composed of two parts: the waveresistance due to each hull itself and that arising from the mutual action between the two hulls.It is then derived that the resistance of catamarans should be the functions of ship form, Froude number and separationlength ratio. A series of computations based on the MichellHavelocks thinship theory were made on the digital computer to investigate the effects of hull separation and speed on the resistance.The calculations show that in the speed range from Froude number 0.30 to 0.36, the interaction between the two hulls may result in favorable interferences if a suitable hull separation is chosen.The paper shows that the optimum hull separation decreases with increasing speed.In the speed range from Froude number 0.36 to 0.50, the interference resistance is always positive and thus the resistance of the twinhull is greater than that of the corresponding one which has a hull separation equal to in finity. The above conclusions are confirmed by model experiments.But quantitatively, the measured resistance and optimum separation are somewhat different from the theoretical predictions.The optimum separation as determined from the model experiments is greater than that obtaind from mathematical computations.The model experiments also show that when the Froude number is less than 0.30, the effect of hull separation on the catamaran resistance is not significant provided that the distance between the two hulls (from centre to centre) is greater than one quarter the ship length. A comparison is also made between the resistances of a catamaran and that of a singlehull ship which has the same length, draught and displacement as that of the twinhull ship.Althougth the catamaran ship has a larger wetted surface which introduces higher frietional resistance, but its resistance quality is superior to the corresponding conventional ship when the Froude number is beyond 0.34.  本文以一般棱形系数0.645的海洋双体船为对象,通过兴波阻力理论计算和模型试验研究,对双体船的阻力问题作了较详细的探讨。双体船的兴波阻力系由自身兴波阻力和干扰阻力两部分所组成,主要是船型形状、佛氏数和间距船长比的函数。根据薄船理论对双体船阻力利用电子计算机进行了一系列计算,研究了不同间距和航速变化对阻力的影响。计算表明,在佛氏数0.30至0.36范围内,尚选择适当的间距,有可能出现有利干扰。在产生有利干扰的区域内,最佳间距随着佛氏数的增加而减小。而在佛氏数0.36至0.50范围内,双体之间的相互作用将增加阻力,因此,双体船的总阻力大于当间距为无限大时的阻力。文中通过模型试验与计算结果作了比较,证实了上述的结论。但在阻力定量和决定最佳间距方面,薄船理论计算与模型试验结果之间尚存在着一定的差距,由模型试验得出的最佳间距往往大于理论计算。试验中并说明当佛氏数小于0.30,如果间距船长比大于0.25,则间距对双体船的阻力影响不大。最后并和一般等长度、等吃水和等排水量的单体船的阻力作了相应的比较,指出虽然在低速时双体船的摩擦阻力较大,但当佛氏数大于0.34,由于双体船具有较大的长度排水量比,其总阻力小于单体船。   << 更多相关文摘 
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