Notch Effect and Frequency Compensation of Dual-Sensor OBC Data in Shallow Water

Reverberation is significant in shallow water and produces obvious notches in OBC spec-tra. It also degrades the quality of sections and increases the difficulty of processing and interpretation. This ...     

合金铸铁激光处理的探讨——Ⅱ.激光辐照工艺参数的控制

用热传导方程控制激光辐照温度,建立了一种新回归方程以控制激光辐照硬化深度,选用卡尔丹公式列热传导方程及同归方程联立求解,可得到同时满足一定的硬化深度及表面最高温度双重要求的工艺参数,此种方法可作为激光硬化处理工艺参数的控制或预报,对本合金铸铁的激光硬化处理,其表面温度的下限应大于其熔点温度,即以表面产生微熔的快速冷凝处理为宜,并以选取低功率慢扫描为最佳。     

凸六边形的相对长边与相对短边

就Doliwaka和Lassak提出的凸n－边形的相对边问题，讨论n＝6的情形，将凸六边形嵌入到平等四边形内（边可重叠），利用对应边的边长比的关系可证任意凸六边形均有相对长边，有平行对边的凸六边形必有相对短边。     

Simulation of Weld Depth in A-TIG Welding with Unified Arc-electrode model

Ｉｔｋｎｏｗｎｔｈａｔｓｍａｌｌａｍｏｕｎｔｓｏｆｆｌｕｘｏｎｔｈｅｓｕｒｆａｃｅｏｆｓｔａｉｎｌｅｓｓｓｔｅｅｌｃａｎｉｎｃｒｅａｓｅｔｈｅｄｅｐｔｈｏｆｗｅｌｄｐｅｎｅ ｔｒａｔｉｏｎｉｎＴＩＧｗｅｌｄｉｎｇｂｙａｆａｃｔｏｒｏｆｔｈｒｅｅ[1] .Ｔｈｉｓｐｒｏｃｅｓｓｉｓｒｅｆｅｒｒｅｄｔｏａｓ”ＡＴＩＧ”ｏｒＴＩＧｗｅｌｄｉｎｇａｃｔｉ ｖａｔｅｄｂｙｆｌｕｘ .Ｔｈｅｒｅｈａｖｅｂｅｅｎｔｈｒｅｅｐｕｂｌｉｓｈｅｄｐｈｙｓ ｉｃａｌｍｅｃｈａｎｉｓｍｓｔｈａｔａｒｅｐｏｓｓｉｂｌｅｃｏｎｔｒｉ…     

用解析方法建立两个三角形的亲似对应(Ⅰ)

本文解决的是射影几何中建立两个三角形亲似对应的问题.本文对亲似对应问题进行了分析,根据亲似对应的特点,将问题简化,并在此基础上推导出建立两个三角形亲似对应的数学公式及计算方法.     

Method for Risky Multiobjective Group Decision-Making and Its Application

The multiobjective group decision-making problem under risk is common in reality. This paper focuses on the study about risky multiobjective group decision-making problem where the index value is not certain. We give indexes classifying method and index normalizing formula of this type problem. By building objective function that minimizes general weighted distance from every alternative to the relatively best and worst alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, and by building another objective function that minimizes general weighted distance from the optimal membership degree of every decision-maker to every alternative to the group optimal alternative and the group inferior alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, which are both based on probability theory and fuzzy theory. Aftermost a model is established which collects group preferences. This method provides a new idea and     

一种改进的相对轨道动力学模型

线性化的Clohessey-Whiltshire(C-W)方程描述相对运动虽然方便,但是精度不高,为了解决这一问题,提出了一种C-W方程的改进形式。首先基于C-W方程的推导,分析了在对中心引力取近似的过程中导致原方程不准确的数学原因和物理现象;然后通过对简化部分的数量级进行分析和比较,将原推导过程中忽略掉的部分重要内容重新予以考虑,并运用数学变换将新加入的内容合并转化,最终给出了一组非齐次线性常系数微分方程,在不增加计算复杂度的情况下提高了精度。仿真验证表明该方程在圆轨道下相对于C-W方程精度改善很多,小椭圆轨道下也消除了C-W方程的长期误差。     

建筑物室外环视中加速绘制算法

提出一种用于建筑物环视系统混合绘制的加速方法,场景划分为主体模型和层次环境的带有深度的图像缓存(sprite with depth),采用BSP树存储场景的具有深度的图像缓存,用模型对存储场景的BSP树应用三维裁剪算法来减少不必要的绘制,并在环视过程中采用生成替代图像缓存方法,加速环视场景的生成.     

杨庄煤矿塌陷湖水资源勘查计算

通过对塌陷湖的实地勘查,运用水均衡原理,计算出该湖可供开采的水资源,认为该塌陷湖可作为淮北市供水后备水源地之一。