CT仪对导弹发动机装药无损探伤的定标方法

本文概述CT仪对导弹发动机装药无损探伤时,可根据CT结果,勿需经过实物发动机静止实验,即可计算出一条完整的P-t曲线,按照规定的弹道指标作为CT的标准,能对本批导弹发动机装药作出是否合格的判断,解决了CT用于导弹发动机装药无损探伤的定标技术难关。

湿式氢气贮柜爆炸伤害效应预测

针对某动力公司工业用氢气贮柜发生的爆炸事故 ,建立了 30 0 m3湿式氢气贮柜爆炸的模型 ,给出了事故模型的初始条件 ,用内能法和 TNT当量法对爆炸伤害效应进行了预测。结果表明 ,对于 30 0 m3湿式氢气贮柜 ,在混入空气整体达爆炸上限和局部达爆炸上限两种情况下 ,氢气柜发生一次爆炸的最高爆炸温度分别为 1 637K和 1 1 2 0 K,最高爆炸超压分别为 5.43× 1 0 5Pa和 3.73× 1 0 5Pa,气柜腾空发生二次爆炸对周围环境的最大人体伤害半径分别为 46.8m和 49.7m,对房屋的最大损伤半径分别为 72 .5 m和 81 .6

The variability of eddy ki/netic energy in the South China Sea deduced from satellite altimeter data

We used fifteen years （1993-2007） of altimetric data, combined from different missions （ERS-1/2, TOPEX/Poseidon, Jason-l, and Envisat）, to analyze the variability of the eddy kinetic energy （EKE） in the South China Sea （SCS）. We found that the EKE ranged from 64 cm2/s2 to 1 390 cm2/s2 with a mean value of 314 cm2/s2. The highest EKE center was observed to the east of Vietnam （with a mean value of 509 cm2/s2） and the second highest EKE region Was located to the southwest of Taiwan Island （with a mean value of 319 cm2/s2）. We also found that the EKE structure is the consequence of the superposition of different variability components. First, interannual variability is important in the SCS. Spectral analysis of the EKE interannual signal （IA-EKE） shows that the main periodicities of the IA-EKE to the east of Vietuam, to the southwest of Taiwan Island, and in the SCS are 3.75, 1.87, and 3.75 years, respectively. It is to the south of Taiwan Island that the IA-EKE signal has the most obvious impact on EKE variability. In addition, the IA-EKE exhibit different trends in different regions. An obvious positive trend is observed along the east coast of Vietnam, while a negative trend is found to the southwest of Taiwan Island and in the east basin of Vietnam. Correlation analysis shows that the IA-EKE has an obvious negative correlation with the SSTA in Nifio3 （5°S-5°N, 90°W-150°W）. E1 Nifio-Southem Oscillation （ENSO） affects the 1A-EKE variability in the SCS through an atmospheric bridge--wind stress curl over the SCS. Second, the seasonal cycle is the most obvious timescale affecting EKE variability. The locations of the most remarkable EKE seasonal variabilities in the SCS are to the east of Vietnam, to the southwest of Taiwan, and to the west of Philippines. To the east of Vietnam, the seasonal cycle is the dominant mechanism controlling EKE variability, which is attributed primarily to the annual cycle there of wind stress curl. In this area, the maximum EKE is observed in autumn. To the southwest of Taiwan Island, the EKE is enlarged by the stronger SCS circulation, which is caused by the intrusion branch from the Kuroshio in winter. Finally, intra-annual and mesoscale variability, although less important than the former, cannot be neglected. The most obvious intra-annual and mesoscale variability, which may be the result of baroclinic instability of the background flow, are observed to the southwest of Taiwan Island. Sporadic events can have an important effect on EKE variability.

CO2/CH4 separation using inside coated thin film composite hollow fiber membranes prepared by interfacial polymerization

Carbon dioxide(CO_2) is greenhouse gas which originates primarily as a main combustion product of biogas and landfill gas. To separate this gas, an inside coated thin film composite(TFC) hollow fiber membrane was developed by interfacial polymerization between 1,3–cyclohexanebis–methylamine(CHMA) and trimesoyl chloride(TMC). ATR-FTIR, SEM and AFM were used to characterize the active thin layer formed inside the PSf hollow fiber. The separation behavior of the CHMA-TMC/PSf membrane was scrutinized by studying various effects like feed gas pressure and temperature. Furthermore, the influence of CHMA concentration and TMC concentration on membrane morphology and performance were investigated. As a result, it was found that mutually the CHMA concentration and TMC concentration play key roles in determining membrane morphology and performance. Moreover, the CHMA-TMC/PSf composite membrane showed good CO_2/CH_4 separation performance. For CO_2/CH_4 mixture gas(30/70 by volume) test, the membrane(PD1 prepared by CHMA 1.0% and TMC 0.5%) showed a CO_2 permeance of 25 GPU and the best CO_2/CH_4 selectivity of 28 at stage cut of 0.1. The high CO_2/CH_4 separation performance of CHMA-TMC/PSf thin film composite membrane was mostly accredited to the thin film thickness and the properties of binary amino groups.

Experimental study on load bearing behavior of large-scaled caps with pile groups

The objective of this investigation was to study the behavior of deep pile caps and the ultimate load-carrying capacity. Four 1/10 scaled models of nine-pile caps were cast and tested on vertical loads to failure. The destruction shapes of pile caps,the correlation between load and displacement,and the internal stresses were analyzed systematically. The results demonstrated that the failures of all the four models are resulted from punching shear; the internal flow of the forces in nine-pile caps can be approximated by "strut-and-tie" model. Furthermore,the failure loads of these specimens were predicted by some of the present design methods and the calculated results were compared with the experimental loads. The comparative results also indicated that the "strut-and-tie" model is a more reasonable design method for deep pile caps design.

A FULL-NEWTON STEP INFEASIBLE INTERIOR-POINT ALGORITHM FOR P_*(κ) LINEAR COMPLEMENTARITY PROBLEM

This paper proposes a new infeasible interior-point algorithm with full-Newton steps for P_*(κ) linear complementarity problem(LCP),which is an extension of the work by Roos(SIAM J.Optim.,2006,16(4):1110-1136).The main iteration consists of a feasibility step and several centrality steps.The authors introduce a specific kernel function instead of the classic logarithmical barrier function to induce the feasibility step,so the analysis of the feasibility step is different from that of Roos' s.This kernel function has a finite value on the boundary.The result of iteration complexity coincides with the currently known best one for infeasible interior-point methods for P_*(κ) LCP.Some numerical results are reported as well.

A robust auto-focus measure based on inner energy

This paper proposes a robust auto-focus(AF) measure based on inner energy. In general, the inner energy of noise pixels is close to zero because the magnitude of gradient and the direction of the noise pixels are random. Therefore, the inner energy can effectively eliminate the influence of noise on image quality assessment. But the gradients of near edge points are consistent with those of edge points, so the inner energy of edge pixels is relatively large, and the detail information of the image can be highlighted. Experimental results indicate that compared with traditional methods, the proposed method has higher accuracy, fewer local peaks, stronger robustness and better practicability. In particular, the evaluation results are close to the subjective evaluation of the human eyes. These results illustrate that the proposed method can be applied in automatic focusing.

The non-interior continuation methods for solving the function nonlinear complementarity problem

In this paper, we propose a new smooth function that possesses a property not satisfied by the existing smooth functions. Based on this smooth function, we discuss the existence and continuity of the smoothing path for solving the P0 function nonlinear complementarity problem (NCP). Using the characteristics of the new smooth function, we investigate the boundedness of the iteration sequence generated by the non-interior continuation methods for solving the P0 function NCP under the assumption that the solution set of the NCP is nonempty and bounded. We show that the assumption that the solution set of the NCP is nonempty and bounded is weaker than those required by a few existing continuation methods for solving the NCP.

The Engine Performance Prediction by Quasi-Steady Method

In this paper, the theory of Quasi-steady is applied to the calculations of turbochargers matching tothe diesel engines and performance prediction. The engine performance prediction programs writtenin language C have been used for calculations of various turbocharged diesel engines. It has been confirmed by the comparisons with experimental data that the results of the calculation are reasonable,reliable and satisfied for the engineering applications.

Thermal Magnifier and Minifier

For thermal conduction cases,one can detect the size of an object explicitly by measuring the temperature distribution around it.If the temperature is the only signature we can obtain,we will give an incorrect judgment on the shape or size of the object by disturbing the distribution of it.According to this principle,in this article,we develop a transformation method and design a dual-functional thermal device,which can create a thermal illusion that the object inside it ＂seems＂ to appear bigger or smaller than its original size.This device can functionally switch among magnifier and miniGer at will The proposed device consists of two layers：the cloak and the complementary material.A thermal cloak can make the internal region thermally ＂invisible＂ while the complementary layer offsets this effect.The combination leads to the illusion of magnification and minification.As a result of finite element simulations,the performances of the illusions are confirmed.

Study on China＇s Economic Vulnerability to Energy Import Using Decomposition Method

Vulnerability means the degree to which that a system is susceptible to suffer damage. This paper focuses on the economic vulnerability to risk of energy import by employing ratio of net energy import to GDP as indicator, and decomposes the vulnerability change into effects of energy import, structure and intensity in order to find out key factors that influence economic security to energy import. Decomposition analysis on China indicates that effect of rising energy import takes more than 90 percent of total vulnerability change during the last 10 years, along with insignificant effect of structural change and intensity decline. International analysis on cross- section data of net energy importers also presents the positive relationship between external energy dependence and economic vulnerability. However, results of America show that long-term effect of energy intensity is much larger than China from 1954 to 2007, which is 70.8% of its total vulnerability change. Experience from developed countries confirms the necessary and validity of improving energy efficiency on depressing economic vulnerability to energy import, which provides lessons for the energy development of China.