基于三阶分析模型的斯特林发动机系统模拟和优化

建立了基于Sage的GPU-3斯特林发动机的三阶分析模型,分析了循环过程中的输出功、效率、p-V图、压降等。结果表明,Sage模型的准确度较高,模拟循环输出功和循环效率的误差分别为12.63%~24.26%和-1.10%~7.98%。回热器是压降、换热量和损最大的部件,压降约为加热器的3倍,冷却器的5倍;换热量约为加热器和冷却器的10倍,循环输出功的70倍;损占整机损的50%以上。分别对不同目数丝网的回热器的长度和直径进行优化,得到的最大循环输出功相比优化前提升了31.1%,且回热器的最大换热量提升了33.9%,最大压降下降了73.5%。在此基础上进一步优化加热器和冷却器,循环输出功最高可提升38.9%。

客户协同产品创新中目标重要度的确定方法

为解决客户协同创新中目标重要度难以准确量化的问题,提出了一种创新目标重要度的确定方法。首先,构建了客户协同产品创新目标体系的基本框架,以保证创新目标的整体性与系统性;其次,提出了三阶定量分析方法,该方法融合了AHP与熵值法相结合的主客观赋权法、多粒度非平衡语义处理方法等,对目标重要度进行计算及修订。最后,通过某手机的客户协同创新设计实例验证了该方法的可行性与有效性。

螺旋锥齿轮制造技术对比研究及应用

针对螺旋锥齿轮制造加工理论进行研究,分析了局部共轭理论、局部综合法、三阶接触分析等加工理论之间的差异点。通过CAGE 4Win、GSHgears、Hyspiral计算机程序应用对比分析,对齿轮加工理论进行验证,有助于螺旋锥齿轮加工新技术的推广应用,提高螺旋锥齿轮设计和加工质量。

Estimating regional coal resource efficiency in China using three-stage DEA and bootstrap DEA models

Based on three-stage data envelopment analysis(DEA) model estimates of resource utilization efficiency of coal,we selected 29 provinces from China's 2012 input-output data and used the bootstrap DEA model to correct the bias.The results show that the mean overall technical efficiency,pure technical efficiency,and scale efficiency was 0.833,0.998,and 0.711 in 2012,respectively.Moreover,the comprehensive technical efficiency score indicates that the scale is invalid.Area utilization efficiencies for the eastern,central,and western regions were 0.917,0.731,and 0.629,respectively.The results prove that there are significant differences in the distribution of coal resources utilization efficiency across regions.

Nonlinear analysis of nano-cluster doped fiber

There are prominent nonlinear characteristics that we hope for the semiconductor nano-clusters doped fiber. Refractive index of fiber core can be effectively changed by adulteration. This technology can provide a new method for developing photons components. Because the semiconductor nano-cluster has quantum characteristics, Based on first-order perturba- tion theory and classical theory of fiber, we deduced refractive index expressions of fiber core, which was semiconductor nano-cluster doped fiber. Finally, third-order nonlinear coefficient equation was gained. Using this equation, we calculated SMF-28 fiber nonlinear coefficient. The equation shows that new third-order coefficient was greater.

Pulse Amplification in Dispersion-Decreasing Fibers with Symbolic Computation

The pulse amplification in the dispersion-decreasing fiber （DDF） is investigated via symbolic computation to solve the variable-coefficient higher-order nonlinear Schrfdinger equation with the effects of third-order dispersion, self-steepening, and stimulated Raman scattering. The analytic one-soliton solution of this model is obtained with a set of parametric conditions. Based on this solution, the fundamental soliton is shown to be amplified in the DDF. The comparison of the amplitude of pulses for different dispersion profiles of the DDF is also performed through the graphical analysis. The results of this paper would be of certain value to the study of signal amplification and pulse compression.

Thermodynamics of Third Order Lovelock Anti-de Sitter Black Holes Revisited

We compute the mass and temperature of third order Lovelock black holes with negative Gauss-Bonnet coefficient a2 〈 0 in anti-de Sitter space and perform the stability analysis of topological black holes. When k = -1, the third order Lovelock black holes are thermodynamically stable for the whole range r＋. When k = 1, we found that the black hole has an intermediate unstable phase for D = 7. In eight dimensional spacetimes, however, a new phase of thermodynamically unstable small black holes appears if the coefficient a is under a critical value. For D ≥ 9, black holes have similar the distributions of thermodynamically stable regions to the case where the coefficient ＆ is under a critical value for D = 8. It is worth to mention that all the thermodynamic and conserved quantities of the black holes with fiat horizon do not depend on the Loveloek coefficients and are the same as those of black holes in general gravity.

论商法拟制性规范的识别与体系解构

法律拟制的本质是虚构性类推,具有漏洞填补、指示参照、规制决断等功能。在对商法拟制性规范的识别上,既有误入功能主义泥淖之状况,也有对形式主义方法的运用失当;同时,在法律拟制与其他法律方法的区分上亦存在一些混乱认识,均需加以澄清。基于商事法律关系中商主体、商行为“二元结构”,参考法律规则结构“新三要素说”,结合法律拟制的“同一化”、“区别化”取向,以“二维三阶分析法”认识、解析商法拟制性规范体系的内在构造,明晰法律拟制适用于商法规范的限度和向度,指导商法拟制性规范的再建构,是一条可探讨的路径。

Unsteady Flow Field under Surge and Rotating Stall in a Three-stage Axial Flow Compressor

The unsteady flow structure between rotor blade-to-blade passages in a three-stage axial flow compressor is experimentally investigated by detailed measurements of unsteady performance characteristics,casing wall pressure fluctuations and their wavelet analyses.The main feature of the test compressor is a capacity tank facility connected in series to the compressor outlet in order to supply compression and/or expansion waves from downstream of the compressor.Research attention is focused on the post-stall characteristics of the surge and rotating stall which occur simultaneously.The influence of the compressor operating point on the unsteady performance curve shows that the surge cycle changes irregularly depending on the steady-state resistance characteristics,and the results of the wavelet analyses of the wall pressure fluctuations suggest that the surge cycle may selectively be determined by the rotating stall cell structure within the rotor cascade.

Asymptotic Analysis in a Gas-Solid Combustion Model with Pattern Formation

The authors consider a free interface problem which stems from a gas-solid model in combustion with pattern formation. A third-order, fully nonlinear, self-consistent equation for the flame front is derived. Asymptotic methods reveal that the interface approaches a solution to the Kuramoto-Sivashinsky equation. Numerical results which illustrate the dynamics are presented.