基于属性质量度的变精度邻域粗糙集属性约简

变精度邻域粗糙集相比于邻域粗糙集具有抗噪容错的能力,但由于重新定义了下近似,正域的划分不再严格,使得属性重要度的可信度降低,在精度改变的情况下无法优先选取最优的属性.针对这一问题,分析变精度邻域粗糙集的下近似,引入邻域内的正确分类率,定义属性质量度,提出一种基于正域的增量和平均正确分类率的增率相结合的属性度量方法.通过和现有的基于属性重要度的属性约简算法做比较,实验结果表明,改进后的属性度量方法对变精度有更好的适应性,在不同变精度阈值下能得到更优的约简结果.

基于属性重要度规则提取算法的高校教学质量评价研究

该文利用粗糙集的分辨矩阵和提取属性重要度分类提取规则的属性约简算法,提出了课堂教学质量评价模型,对构建的教学质量评价指标体系建立课堂决策系统信息表。通过算例分析,获取影响教学质量的最优指标,为教学改革提供重要的参考依据。

可变精度邻域区间值决策表的属性约简

区间值决策表可以通过区间刻画对象相对于条件属性的取值,其在现实生活中运用非常广泛,该文在此基础上提出一种启发式约简算法。首先,为了提高信息系统的可辨识性,在区间值决策系统上引入可变精度阈值α与邻域阈值δ;随后,重新定义了决策表的上近似、下近似与正域;最后,定义属性质量度,以判定是否将条件纳入约简集合。为了更好地理解该算法的执行过程,该文进行了案例分析,并在4个数据集上完成了实验。实验结果表明,该算法具有良好的可行性,且其在准确率上优于另2种算法。

Evaluation of Feed and Feeding Regime on Growth Performance, Flesh Quality and Fecal Viscosity of Atlantic Salmon(Salmo salar L.) in Recirculating Aquaculture Systems

The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon （Salmo salar L.） in recirculating aquaculture systems （R.AS） were investigated. Fish （initial body weight of 1677 g＋ 157 g） were fed with four commercial feeds （Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Hart ye-HY） in two feeding regimes （80% and 100% satiation） for 78 d. The results showed that salmon specific growth ratio （SGR） and weight gain ratio （WGR） were significantly affected by feed type and feeding regime （P〈0.05）. Feed conversion ratio （FCR） varied between 0.93 and 3.40, which was significantly affected by feed type （P〈0.05）, and slightly improved with increased satiation degree. The activities of digestive enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime （P〈0.05）, increasing with satiation degree. Flesh qualities for vitamin E, hydroxyproline （HYP）, liquid loss and muscle pH among all groups showed significant differences （P〈0.05）, ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

Effect of Some Processing Variables on the Quality Attributes of Yam Flour

The effect of varied processing variables （yam slice thickness, drying temperatures and type of drying） were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values （6.20%-6.87%） followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.

The Relationships Between Milk Constituents and Various Milk Properties in Anatolian Buffaloes

The objectives of this study were to investigate the relationships among milk composition, renneting time, urea concentration, acidity, density and pH of Anatolian Buffaloes＇ milk. As a total of 115 individual milk samples from 53 Anatolian buffalo cows that calved in 2004 and 2005 on days of their lactations 30 ± 15, 60 ± 15, 90 ±15, 120 ± 15, 150 ± 15, 180± 15, 210 ±15, 240 ± 15 and 270 ± 15 in 8 units of lhkpmar village were collected in morning milkings in June, September, December and March. Samples were analysed for total dry matter （TDM）, fat, protein, ash, density, pH, acidity, renneting time and urea content. Data were classified according to the following environmental factors： lactation stages： （30 ± 15, 60 i 15, 90 ±15 days）： 2 （120±15, 150 ± 15, 180 ± 15 days）： 3 （210 ± 15, 240 ± 15, 270± 15 days）; calving year： 1 （2004）, 2 （2005）; calving season： 1 （January-May）, 2 （September and October）; month of samples collection： 1 （June）, 2 （September）, 3 （December）, 4 （March）; lactation order： 1 and 2：1, 3 and 4：2, 5 and 6：3. Means and correlation coefficients for the characteristics investigated were calculated. There were negative significant correlations between daily milk yield with TDM, fat and protein percentages, and between pH and all of the milk constituents. Density reduces as TDM, fat and protein contents increase. Relationships between density and coagulation time with milk yield and pH were not significant. Relationships between milk urea concentration with none of milk constituents, milk yield, density, pH and titratable acidity were not significant statistically. It was concluded that genetic selection has to be directed towards increasing fat, protein and total not fat dry matter yields. Under selection programs in which milk yield is taken into consideration, fat and protein yields also increase, but fat and protein concentrations decrease.

Geometric Property(T)

This paper discusses "geometric property(T)". This is a property of metric spaces introduced in earlier works of the authors for its applications to K-theory. Geometric property(T) is a strong form of "expansion property", in particular, for a sequence(Xn)of bounded degree finite graphs, it is strictly stronger than(Xn) being an expander in the sense that the Cheeger constants h(Xn) are bounded below.In this paper, the authors show that geometric property(T) is a coarse invariant,i.e., it depends only on the large-scale geometry of a metric space X. The authors also discuss how geometric property(T) interacts with amenability, property(T) for groups,and coarse geometric notions of a-T-menability. In particular, it is shown that property(T) for a residually finite group is characterised by geometric property(T) for its finite quotients.

Properties of color-flavor locked strange quark matter and strange stars in a new quark mass scaling

Considering the effect of one-gluon-exchange interaction between quarks,the color-flavor locked strange quark matter and strange stars are investigated in a new quark mass density-dependent model.It is found that the color-flavor locked strange quark matter can be more stable if the one-gluon-exchange effect is included.The lower density behavior of the sound velocity in this model is different from the previous results.Moreover,the new equation of state leads to a heavier acceptable maximum mass,supporting the recent observation of a compact star mass as large as about 2 times the solar mass.