摘要：The design of an annular combustion chamber in a gas turbine engine is thebackbone of this *** is specifically designed for a low bypass turbofan engine in a jettrainer *** combustion chamber is positioned in between the compressor and *** has to be designed based on the constant pressure,enthalpy addition *** presentmethodology deals with the computation of the initial design parameters from benchmarking ofreal-time industry standards and arriving at optimized *** is then studied for feasibilityand *** the various dimensions of the combustor are calculated based on differentempirical *** air mass flow is then distributed across the zones of the *** cooling requirement is met using the cooling *** the variations of parameters atdifferent points are *** whole combustion chamber is modeled using Siemens NX8.0,a modeling software and *** model is then analyzed using various parametersat various stages and levels to determine the optimized *** aerodynamic flowcharacteristics is simulated numerically by means of ANSYS 14.5 software *** air-fuelmixture,combustion-turbulence,thermal and cooling analysis is carried *** analysis isperformed at various scenarios and *** results are then presented in image outputsand graphs.

摘要：Employing the intermediate derivatization method（IdM）, twenty novel 1,3,4-oxadiazole derivatives containing arylpyrazoloxyl moiety were designed and synthesized. The structures of the title compounds were identified by1 H NMr,13 C NMr, MS and elemental analyses, compound 4 was further identified by single-crystal X-ray diffraction. Antifungal activities against rice sheath blight（rSB） and sorghum anthracnose（SA） were evaluated by the mycelium linear growth rate method. Compounds 4, 16 and 20 displayed significant activities against rSB（EC50= 0.88 mg/L, 0.91 mg/L and 0.85 mg/L, respectively）,higher than the reference tebuconazole; While compound 3 exhibited higher activity against SA（EC50= 1.03 mg/L）, equal to commercial pyraclostrobin（EC50= 1.06 mg/L）. The study showed that compound 20 is a promising fungicide for further development.

摘要：The usage of open communication infrastructure for transmitting the control signals in the Load Frequency Control (LFC) scheme of power system introduces time delays. These time delays may degrade the dynamic performance of the power system. This paper proposes a robust method to design a controller for multi-area LFC schemes considering communication delays. In existing literature, the controller values of LFC are designed using time domain approach which is less accurate than the proposed method. In proposed method, the controller values are determined by moving the rightmosteigenvalues of the system to the left half plane in a quasi-continuous way for a preset upper bound of time delay. Then the robustness of the proposed controller is assessed by estimating the maximumtolerable value of time delay for maintaining system stability. Simulation studies are carried out for multi-area LFC scheme equipped with the proposed controller using Matlab/simulink. From the results, it has been concluded that the proposed controller guarantees the tolerance for all time delays smaller than the preset upper bound and provides a bigger delay margin than the existing controllers.

摘要：在薄壁管中引入预折叠图案已被证明可以有效增强其能量吸收能力.然而,仅仅靠预折叠图案设计所提高的能量吸收能力已经达到天花板,难以进一步提高。本研究为解决这一问题,提供了一种全新的技术路线.我们首先设计了一种结构均匀的预折叠薄壁管作为参考结构.然后,我们对参考结构的壁厚进行非均匀化设计。在保持薄壁管总质量不变的情况下,加厚了塑性变形相对较大的局部区域的壁厚,同时变薄了塑性变形相对较小的局部区域的壁厚。这种非均匀设计方式使薄壁管的整体变形更加协调,不仅显著提高了结构的比吸能(SEA),而且降低了峰值力(PCF),实现了SEA和PCF的更优组合.

摘要：A new fabrication technology for three-dimensionally buried silica on silicon optical waveguide based on deep etching and thermal oxidation is presented. Using this method, a silicon layer is left at the side of waveguide. The stress distribution and effective refractive index are calculated by using finite element method and finite different beam propagation method, respectively. The results indicate that the stress of silica on silicon optical waveguide fabricated by this method can be matched in parallel and vertical directions and stress birefringence can be effectively reduced due to the side-silicon layer.

摘要：SdrAM (Synchronous drAM) has become the memory standard in many digital system designs, because of low price and high read/write speed. In this paper, Based on the analysis of the working principle and characteristics of SdrAM, an SdrAM controller design method is proposed based on field programmable logic gate array FPGA. In order to reduce resource consumption and increase the read and write speed of SdrAM, the performance control of SdrAM is further optimized. We designed SdrAM controller by using Verilog HdL and Altera Quartus II 14.1 software, and simulated about this design with Model Sim-Altera 10.3c software. Then we verified this design by using Cyclone V 5CSEMA5F31C6 FPGA in dE1-SoC development board. The verification results show that the SdrAM is initialized successfully, the input and output data are completely consistent, and it has stable refresh and read and write functions. The SdrAM controller design meets the requirements.

摘要：In the injection molding process, plastic products are difficult to demold due to friction force between the cavity and products, thus, finished products might be deformed or damaged. Therefore, designers should add a draft angle to the geometric surface of products, which is parallel to the unloading direction, in order to help the products eject smoothly from the cavity. This study uses CAd software as the main architecture to develop the function of automatic draft angle recognition and construction. The study is divided into three stages. First, the geometric features of products are identified in the CAd model by induced algorithm, then the quilts to be added in the draft design are determined and classified. Finally, draft angles are created in different ways according to different surfaces. An algorithm suitable for automatic draft recognition and construction, as well as the constraints of automatic creation of draft angle, is proposed. The feature recognition algorithm of this study can automatically inspect 90% of the surfaces to be drafted, and the automatic creation of draft features can economize 80% of required mouse clicks, thus, effectively increasing draft angle design efficiency, and preventing errors in mold design and manufacturing.

摘要：This paper introduces CBFEM （component-based finite element model） which is a new method to analyze and design connections of steel structures. design focused CM （component model） is compared to FEM （finite elements models）. Procedure for composition of a model based on usual production process is used in CBFEM. Its results are compared to those obtained by component method for portal frame eaves moment connection with good agreement. design of moment resistant column base is demonstrated by a case loaded by two directional bending moments and normal force. Interaction of several connections in one complex joint is explained in the last example. This paper aims to provide structural engineers with a new tool to effectively analyze and design various joints of steel structures.

摘要：To deal with the stress interference caused by simultaneous propagation of multiple fractures and the wettability reversal and physical property changes of the reservoir caused by fracturing fluid getting in during large-volume fracturing of tight oil reservoirs through a horizontal well, a non-planar 3d fracture growth model was built, wettability reversal characterizing parameters and change of relative permeability curve were introduced to correct the production prediction model of fractured horizontal well, a fracturing design optimization software(Fr Smart) by integrating geological and engineering data was developed, and a fracturing design optimization approach for tight oil reservoirs based on fracture control was worked out. The adaptability of the method was analyzed and the fracture parameters of horizontal wells in tight oil reservoirs were optimized. The simulation results show that fracturing technology based on fracture control is suitable for tight oil reservoirs, and by optimizing fracture parameters, this technology makes it possible to produce the maximum amount of reserves in the well-controlled unit of unconventional reservoirs. The key points of fracturing design optimization based on fracture control include increasing lateral length of and reducing the row spacing between horizontal wells, increasing perforation clusters in one stage to decrease the spacing of neighboring fractures, and also avoiding interference of old and new fracturing wells. Field tests show that this technology can increase single well production and ultimate recovery. Using this technology in developing unconventional resources such as tight oil reservoirs in China will enhance the economics significantly.

摘要：The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the roll-cone,which will need more trip out time to replace the roller *** study provides an entire analysis on stress as well as strength for teeth and tooth holes in loaded *** of tooth drop from matrix within roller *** optimized interferences of teeth inserted into the bit can be reasonably obtained by the critical interference derived from some relevant influence factors on the tooth-fixing quality of roller bits.