表冷器经验公式通用性的探讨

表冷器的经验公式都是通过实验测试并进行线性回归得到的。本文通过实验对表冷器经验公式中表冷器高度、长度以及通水管数的通用性进行研究，结果表明，同一厂家生产的结构特性相同的表冷器的经验公式具有通用性。     

凝胶过滤色谱测定高分子量聚乙烯醇分子量和分子量分布

用凝胶过滤色谱对高分子量聚乙烯醇分子量、分子量分布进行剖析。采用Plaquagel-OH色谱柱,0.25mol/LNaNO3,0.01mol/L Na2HPO4-NaH2PO,pH=7的缓冲溶液流动相,流速1ml/min,示差折光检测器,柱温30℃,聚环氧乙烷作标准物。该方法能显著缩短分析时间,提高准确性,可用于对高聚合度聚乙烯醇进行研究和指导生产。     

高水头弧形闸门伸缩式水封的黏弹性仿真计算方法

认为止水材料的蠕变和应力松弛是由于材料参数的变化而引起的，把描述橡胶类材料应变能密度函数中的物理参数假设成与时间有关的黏弹性函数。在此基础上改进材料应力张量与应变张量的关系式，得到了改进的Mooney-Rivlin公式，给出了一种考虑止水材料黏弹性性质的伸缩式水封仿真计算方法。分析得出，止水材料由于受周边结构的限制，材料黏弹性阶段除顶点垂直位移不变，关键结点的其它位移并没有因材料的蠕变而显著变化，材料的蠕变有提高封头顶点接触应力的趋势，不会降低水封的水密性。通过工程实例，给出了140m水头下、封头与面板间隙控制在30mm内的可行并较优的伸缩式水封的断面。     

非径向对称随机向量的研究

本文利用过定点的Copula的最佳上、下界,构造了4个奇异Copula;证明了任意Copula与其生存Copula差的绝对值的上确界是三分之一;给出了度量随机变量非径向对称的方法;研究了最大非径向对称随机变量的性质及相关性度量的界。     

Efficient Legendre moment computation for grey level images

Legendre orthogonal moments have been widely used in the field of image analysis. Because their computation by a direct method is very time expensive, recent efforts have been devoted to the reduction of computational complexity. Nevertheless, the existing algorithms are mainly focused on binary images. We propose here a new fast method for computing the Legendre moments, which is not only suitable for binary images but also for grey level images. We first establish a recurrence formula of one-dimensional (1D) Legendre moments by using the recursive property of Legendre polynomials. As a result, the 1D Legendre moments of order p, L_p=L_p(0), can be expressed as a linear combination of L_p-1(1) and L_p-2(0). Based on this relationship, the 1D Legendre moments L_p(0) can thus be obtained from the arrays of L₁(a) and L₀(a), where a is an integer number less than p. To further decrease the computation complexity, an algorithm, in which no multiplication is required, is used to compute these quantities. The method is then extended to the calculation of the two-dimensional Legendre moments L_pq. We show that the proposed method is more efficient than the direct method.     

一种按时间切换的最速控制方法

基于初始状态空间下的子空间概念，提出了一种按时间进行切换的最速控制方法，不需要求取开关线或开关面。数字仿真结果表明，采用这一方法是完全可行的。     

KINEMATIC VISCOSITY-TEMPERATURE BEHAVIOR OF HEAVY TBP-FRACTIONS (455°C+) OF ARABIAN CRUDE OILS

A generalized kinematic viscosity-temperature correlation for undefined liquid heavy petroleum fractions has been developed to represent the data for a wide range of temperature from 100°C to 200°C. The correlation is based on the experimental kinematic viscosity data of true boiling point fractions of four Arabian crude oils. The characterization property required for estimation is 50% boiling point. The proposed correlation fits the experimental data with an overall absolute error of 6.1%. Experimental measurements of kinematic viscosity of heavy true boiling point fractions of Arabian crude oils were also obtained in order to develop the proposed correlation.     

正交试验法于优选白瓷坯料配方中的应用

对长石、石英、龙岩土、莱阳土４种因素各取４个水平，用正交表Ｌ１６（４５）安排１６个试验，分析了这１６个试验产品的吸水率、白度、热稳定性与每种因素各水平之间的关系．得出了白瓷坯料的最佳配方。其中，长石１９，石英２１，龙岩土２１．莱阳土０．     

正庚烷-甲苯-三甘醇三元体系液-液相平衡数据的测定与关联

利用气相色谱法测定了常压下２５℃、４０℃和５０℃时正庚烷－甲苯－三甘醇体系的液－液相平衡数据，采用峰面积归一化法定量，所得数据准确、可靠。用ＮＲＴＬ模型对所测数据进行了热力学关联，求出了相应的模型参数。用该模型对本三元体系进行了预测，结果令人满意。