R0-代数与BL-代数中的素滤子定理

R1-代数与BL-代数在模糊逻辑的研究中有重要作用,这与布尔代数在经典逻辑中的作用类似。本文通过一个特殊集x^-1F分别给出Ro-代数及BL-代数素滤子的一个等价条件,并给出BL-代数的一个新性质。应用这些结果分别得到Ro-代数与BL-代数的素滤子定理。     

R0-代数(NM-代数)的布尔MP滤子与布尔MP理想

在R0-代数中引入布尔MP滤子与布尔MP理想的概念,给出其若干充要条件,研究了它们与素滤子、极大MP滤子的关系。通过反例指出了关于超MP滤了的一个错误结论,给出超MP滤子的一个充分必要条件。在此基础上研究了R0-代数的结构,用布尔MP滤子与布尔MP理想刻画了二部R0-代数、强二部R0-代数的特征。     

R0代数的对偶代数

对于R0代数，给出了它的一个等价形式，并建立了它的对偶代数，从此刻划了R0代数内部结构的特征，也为从语义的角度进一步研究模糊逻辑系统提供了一个新的途径。     

R0-代数上的同余关系

研究了Ro-代数上的同余关系,首先通过探讨一类Ro-代数,建立起滤子与同余关系之间的联系,进而深入到其乘积上,最后以模糊滤子为工具定义R0－代数上的同余关系,讨论了滤子与模糊滤子之间的联系,并给出了由同余诱导的商R0－代数。     

R0代数的注记

讨论了R0代数与MV代数的关系，给出了R0代数的一种根。     

BR0-代数的无序表示形式及WBR0-代数性质

对BR0-逻辑代数进行了进一步研究,得到了BR0-逻辑代数的一种无序表示形式,使得BR0-代数中的序关系蕴涵于BR0-代数的基本运算⊕和→之中,并根据BR0-代数的无序表示形式提出了WBR0-代数理论,初步地讨论了其中的性质.     

三角代数的模糊滤子

引入三角代数和三角代数中滤子的概念,研究三角代数中滤子的性质.给出了三角代数中模糊滤子的概念,进一步给出三角代数模糊滤子的等价刻画;研究了三角代数中滤子与模糊滤子之间的关系,并证明由滤子可以诱导出模糊滤子,反之,由模糊滤子也可以诱导出滤子.     

赋值为R0-模糊集的逻辑系统

研究了赋值的R0－模糊集逻辑系统W^－X的语义理认,到了若干结果,特别是对W^-x而言,F（S）的α－重言式类只有1／2－重言式类与重言式类两类。     

MTL代数的蕴涵滤子与正蕴涵滤子

在MTL代数M上引入了蕴涵滤子、正蕴涵滤子的概念,研究了它们的性质,给出了M的非空子集成为蕴涵滤子及正蕴涵滤子的充要条件和M的蕴涵滤子成为正蕴涵滤子的充要条件.讨论了蕴涵滤子与正蕴涵滤子的关系,得到了M的每一个正蕴涵滤子都是蕴涵滤子,但反之不真.     

预线性剩余格与逻辑代数

本文首先讨论了剩余格与FI代数之间、FI代数与MV代数之间的关系,对已有结果进行了改进。随后提出了预线性剩余格的概念,证明了预线性剩余格是BR_0代数与BL代数的基础,从而也就是著名的MV代数、R_0代数、G代数与Ⅱ代数的公共基础。     

Experimental evaluation of R22 and R407C evaporative heat transfer coefficients in a vapour compression plant

The mean heat transfer coefficients of R22 and R407C in the coaxial counterflow evaporator (20 mm ID) of a refrigerating vapour compression plant have been experimentally measured. The experimental conditions under which heat transfer coefficients were determined reflect a typical working situation for small-scale refrigeration systems. The heat flux ranged from 1.9 to 9.1 kW/m² and the mass flux was varied from 30 to 140 kg/m² s. The results illustrate that the R22 heat transfer coefficient is always greater than that of R407C. Furthermore, a comparison carried out between the experimental data and those predicted by means of the most credited literature relationships showed a strongly overprediction for R407C coefficients.     

Asymptotic equivalence of some adaptive biquad notch filters

A diverse choice of biquad designs is available for adaptive notch filtering or line enhancement (ANF/ALE) applications. We consider one such biquad proposed over a decade ago by David and coworkers and show its equivalence to two other formulations in terms of their pole-zero pair locations in thez-plane. By equivalence, we imply that all these adaptive IIR filters possess comparable asymptotic performance. Further, a simple modification, involving only a normalizing factor, is seen to enhance the performance of this filter. This modified ANF/ALE design is then shown to be equivalent to two other recently proposed adaptive biquads.     

On the computation of conjugacy classes of Chevalley groups

In this paper an algorithm is presented to determine the number of semisimple conjugacy classes for a given centralizertype for the Chevalley groupsSL _n(q) andSU _n(q). Moreover we give the exact number of regular semisimple classes of this groups and a summary of results on the generic classnumber of exceptional Chevalley groups of adjoint type.The first author acknowledges financial support by a grant of the Deutsche Forschungsgemeinschaft     

Decomposition of algebras overF q (X 1,...,X m )

LetA be a finite dimensional associative algebra over the fieldF whereF is a finite (algebraic) extension of the function fieldF _q(X ₁,...,X _m). Here F_q denotes the finite field ofq elements (q=p^l for a primep). We address the problem of computing the Jacobson radical Rad (A) ofA and the problem of computing the minimal ideals of the radical-free part (Wedderburn decomposition). The algebraA is given by structure constants overF andF is given by structure constants overF _q(X ₁,...,X _m). We give algorithms to find these structural components ofA. Our methods run in polynomial time ifm is constant, in particular in the casem=1. The radical algorithm is deterministic. Our method for computing the Wedderburn decomposition ofA uses randomization (for factoring univariate polynomials overF _q).Research partially supported by Hungarian National Foundation for Scientific Research (OTKA), Grants 2581, F4116 and EC Cooperative Action IC 1000 (ALTEC).     

Mass flow characteristics and empirical modeling of R22 and R410A flowing through electronic expansion valves

The applications of electronic expansion valves (EEVs) into multi-type heat pumps and inverter heat pumps in building air-conditioning systems have increased for comfort environmental control and energy conservation. However, test data and mass flow models of EEVs are very limited in open literature. The objectives of this study are to investigate the mass flow characteristics of R22 and R410A through EEVs and to develop an empirical correlation for the prediction of mass flow rates of R22 and R410A through EEVs. Mass flow rates through six EEVs were measured by varying the EEV opening, inlet and outlet pressures, and the subcooling. Mass flow rates of R410A were compared with those of R22 at the same test conditions. Based on the experimental data, an empirical correlation for mass flow predictions in EEVs was developed by modifying the orifice equation. The predictions of the present correlation showed good agreement with the measured data with average and standard deviations of 0.76% and 5.9%, respectively. Approximately 92% of the measured data were within ±10% of the predictions.