Global Optimization in Any Minkowski Metric: A Permutation-Translation Simulated Annealing Algorithm for Multidimensional Scaling

It is well known that considering a non-Euclidean Minkowski metric in Multidimensional Scaling, either for the distance model or for the loss function, increases the computational problem of local minima considerably. In this paper, we propose an algorithm in which both the loss function and the composition rule can be considered in any Minkowski metric, using a multivariate randomly alternating Simulated Annealing procedure with permutation and translation phases. The algorithm has been implemented in Fortran and tested over classical and simulated data matrices with sizes up to 200 objects. A study has been carried out with some of the common loss functions to determine the most suitable values for the main parameters. The experimental results confirm the theoretical expectation that Simulated Annealing is a suitable strategy to deal by itself with the optimization problems in Multidimensional Scaling, in particular for City-Block, Euclidean and Infinity metrics.     

ROLE OF α-PSEUDO-UNIVEX FUNCTIONS IN VECTOR VARIATIONAL-LIKE INEQUALITY PROBLEMS

In this paper, we introduce a new class of generalized convex function, namely, a-pseudounivex function, by combining the concepts of pseudo-univex and α-invex functions. Further, we establish some relationships between vector variational-like inequality problems and vector optimization problems under the assumptions of α-pseudo-univex functions. Results obtained in this paper present a refinement and improvement of previously known results.     

A theoretical model for mid-and low-latitude ionospheric electric fields in realistic geomagnetic fields

The geomagnetic fields, which play important roles in the ionospheric dynamo, can greatly affect the global distribution of ionospheric electric fields, currents and other ionospheric electrodynamics phenomena. In the study of ionospheric electrodynamics phenomena, such as the longitudinal variations of ionospheric electric fields, the non-dipolar component of the geomagnetic fields must be taken into account. In this paper, we deduce a theoretical electric field model for ionospheric dynamo at mid- and low-latitude which adopt a modified magnetic apex coordinates system. In the new electric field model, the geomagnetic fields can be calculated from either the IGRF model or the dipole field model, and the neutral winds and conductivities are calculated based on empirical models. Then the dynamo equation for the electric potential is finally solved in terms of the line-by-line iteration method, and the ionospheric electric fields and currents are derived from the calculated potential. Our model can reproduce the main features of the ionospheric electrodynamics processes, so it will be a useful tool for the investigation of the upper atmosphere and ionosphere.     

基于不同摄像机配置的空间点检测模型及精度研究

针对空间点检测问题给出了一种简便而精确的空间点检测方法并建立了实验环境下的数学模型,提出了视差为零时,所测得的空间点深度最接近真实值的假设,并得到如下结论：给定空间点,深度不变,基线越短,光轴的夹角越小；深度改变时,基线一定,则深度越长,夹角越小。推导出在不同基线、不同深度下摄像机光轴之间理想夹角的数学模型并通过实验进行了验证。该方法对实际双目检测系统的摄像机配置有一定的指导作用。     

水轮发电机组H∞状态反馈综合最优控制系统

根据实际工程应用的特点，改进了Ｈ_∞状态反馈控制的算法，并给出了一种选择Ｈ_∞权矩阵的方法；以此为基础设计及研究了一种能综合控制水轮发电机组的励磁和导叶开度，集励磁调节器、调速器功能于一体的综合控制系统．结果表明，该控制器在基本不影响系统响应性能的情况下，能明显地改善系统的鲁棒性．     

鲁米诺—过氧化氢—奎宁化学发光体系测定微量奎宁

本文报导了鲁米诺—过氧化氢—奎宁化学发光体系,建立了测定微量奎宁的最佳条件。对6.6×10~(-6)mol/L奎宁测定的变异系数为1%。该法可用于测定药物中的奎宁,结果良好。     

饲育条件下Semisulcospiens decipiens的生长

在饲育温度条件下研究了Ｓ．ｄｅｃｉｐｉｅｎｓ的生长和产仔数及与饲育水温的关系。结果表明水温在上升期和下降期，新生贝和稚贝的生长速度较快，产仔数也较多．成体贝在水温１１℃～２９℃时，都可产出新生贝，以１８℃～２４℃时产出较多．在高温饲育条件下，成体贝的生长速度缓慢。     

固体吸附制冷系统发生器温度场数值模拟

以内燃机排气－固体吸附制冷系统为背景，建立了固体吸附制冷系统发生器瞬态温度场数值计算模型，并讨论模型中涉及的部分物性参数。通过实验验证，该模型能较好地模拟发生器内瞬态温度场。     

带观测器的电液力伺服变极点数控系统的设计

本文在阐述变极点最优控制原理及其在电液力伺服系统中的实施之基础上，又进行了变极点控制的离散化处理和离散降维观测器对系统的状态重构，解决了系统稳定性与响应速度的矛盾，为该系统微机控制软、硬件的实观奠定了理论基础     

高温涂层自愈合性能的研究

探讨了用涂层的高温透气性的变化率评价涂层自愈合性的实验方法，研究了涂层高温自愈合能力的可能性，并用该方法研究了玻璃质涂层的高温自愈合性能．