Multi-objective design of vehicle suspension systems via a local diffusion genetic algorithm for disjoint Pareto frontiers

This article presents a multi-objective design optimization study of a vehicle suspension system with passive variable stiffness and active damping. Design of suspension systems is particularly challenging when the effective mass of the vehicle is subject to considerable variation during service. Perfectly maintaining the suspension performance under the variable load typically requires a controlled actuator to emulate variable stiffness. This is typically done through a hydraulic or pneumatic system, which can be too costly for small/medium pick-up trucks. The system in this article employs two springs with an offset to the second spring so that it engages during large deformation only, thereby providing passive variable stiffness without expensive hydraulics. The system damping is assumed to be controlled via variable viscosity magnetizable fluid, which can be implemented in a compact, low-power set-up. Performance indices from the literature are evaluated at minimum and maximum weight, and regarded as objectives in a multi-objective problem. As the individual objectives are prone to having local optima, the multi-objective problem is prone to having a disjointed Pareto-space. To deal with this issue, a modification is proposed to a multi-objective genetic algorithm. The algorithm performance is investigated via analytical test functions as well as the design case of the suspension system.     

求解两物种小系统发育问题的遗传算法题

基于复制-丢失比对(DLA)问题模型,研究了复制-丢失(D-L)演化模型下两物种(2-species)小系统发育问题(SPP),缩写为2-SPP-DL问题。通过引入比对算法、标记算法及3种智能变异算子,提出了求解2-SPP-DL问题的遗传算法——G2SP算法。G2SP算法采用普通算子和智能算子相结合的方式,普通算子能有效地保持种群的多样性,而智能算子则能提高种群的收敛性,使其更快地进化到最优解区域。利用4种真实菌属的tRNA和rRNA基因数据对算法性能进行测试,实验结果表明,G2SP算法能够获得较PBLP算法更小的进化代价,是求解2-SPP-DL问题的一种有效方法。     

Exact equation and an algorithm for reliability evaluation of K-out-of-N:G system

An expression for reliability of K-out-of-N:G system is proposed. An algorithm for computing reliability of K-out-of-N system is given. It is an easy to implement, fast and memory efficient algorithm and helps to improve the computational efficiency considerably.     

N -linked oligosaccharide in MSP-1 and its implication for scallop calcification

We speculated the structure of the N-linked oligosaccharides enzymatically released from the organic matrix (OM) component in the foliated layer of Patinopecten yessoensis. The 80 kDa component of the soluble OM was detected by lectin blotting and was identified as MSP-1 using liquid chromatography/mass spectrometry (LC/MS/MS). LC/MS/MS analysis of the N-glycan liberated from MSP-1 detected a hybrid-type N-glycan, which contained sulfite and sialic acid at its terminus based on the characteristic Y ions. The data strongly imply that MSP-1, a sulfated OM glycoprotein, participates in molluscan biomineralization by creating a favorable environment for calcium ion uptake through sulfite acid and sialic acid. Further analyses of oligosaccharides linked to the OM components in wide variety of species and shell microstructures may definitely contribute in elucidation of molluscan biomineralization at the molecular level.     

多目标遗传算法在电梯主动导轮系统集成优化设计中的应用

介绍了一种基于多目标遗传算法的电梯主动导轮系统集成结构和控制器优化设计方法。在本方法中．电梯主动导轮结构参数和主动控制器参数同时作为优化设计变量，电梯系统性能和控制代价作为优化设计目标。这是一个复杂的多目标优化问题。由于控制器具有特定的结构，多目标遗传算法直接被用来求解该多目标集成优化问题。这样不仅可以避免权函数的选择，而且一次运行就可以求出所有的Pareto最优解。最后用一个实验室比例电梯模型作为例子来说明该设计过程。     

An <Emphasis Type="Italic">hp</Emphasis>-adaptive finite element/boundary element coupling method for electromagnetic problems

We present an hp-version of the finite element / boundary element coupling method to solve the eddy current problem for the time-harmonic Maxwell’s equations. We use H(curl, Ω -conforming vector-valued polynomials to approximate the electric field in the conductor Ω and surface curls of continuous piecewise polynomials on the boundary Γ of Ω to approximate the twisted tangential trace of the magnetic field on Γ. We present both a priori and a posteriori error estimates together with a three-fold hp-adaptive algorithm to compute the fem/bem coupling solution with appropriate distributions of polynomial degrees on suitably refined meshes.