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提出了决策表中决策属性相对于条件属性的条件信息量的概念,由此从信息量角度给出了一致决策表的属性约简方法,并且证明了该方法与属性约简的代数方法是一致的,通过实例表明该方法是可行的和有效的. 相似文献
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为进一步探讨形式背景的属性约简,基于简化的可辨识属性矩阵给出概念格的布尔矩阵的定义,并证明此布尔矩阵的初等行变换与辨识函数的运算是等价的。提出形式背景属性约简的方法以及属性特征的判别方法。 相似文献
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使用粗糙集理论中的概念来定义属性重要性,这样更适合粗糙集中的知识发现。讨论了基于属性重要性的属性约简算法,这种方法采用了属性的重要性作为启发式信息,避免了复杂的运算。 相似文献
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运用概念的闭标记研究了强协调决策形式背景的核心属性问题。通过概念的闭标记得到了判定强协调决策形式背景的协调集的方法,并且定义了计算约简集的函数,从而得到了约简集,最后通过简单的集合运算得出协调决策形式背景的核心属性。 相似文献
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杨帆 《郑州轻工业学院学报(自然科学版)》2011,26(6):35-37
基于Rough Set理论的属性约简,提出分2步求得属性约简的新算法:第1步利用二进制辨识矩阵计算出属性约简集;第2步利用可辨识矩阵以及属性的重要性启发地求属性约简,并检查此约简是否属于第1步求出的约简集,以确定此约简是否为较佳的属性约简.理论分析和实验表明,该算法是一种直观、有效的属性约简算法. 相似文献
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提出了一种基于粗糙集理论中的属性约简找出影响大肠杆菌发酵液中谷氨酸脱羧酶产量的重要因素的新方法及基于集合覆盖的属性约简新算法.通过采用均匀设计的思想来获得组合培养基,利用改进的属性约简算法对大肠杆菌培养基因子进行优化.实验结果表明,提出的方法能很好的得出影响谷氨酸脱羧酶产量的几个重要因素,从而进行大肠杆菌培养基优化. 相似文献
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粗糙集理论是一种对数据进行约简的有效工具。文章运用粗糙集理论对评价指标进行了属性约简,并根据各指标包含信息量的大小确定权重,构建了基于粗糙集理论的指标综合评价模型。 相似文献
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从社会属性的角度对纺织重点服装的社会历史价值进行分析,从国家社会治理的高度来认识这一传统产业、民生产业与社会、社会文明进步发展的联系。也对服装业的人才培养、专业方向、设计理念、产业发展提出独特的看法。 相似文献
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《Food Reviews International》2013,29(4):367-388
Phenolic compounds like simple phenols, flavonoids, and phenolic acids are commonly in foods of plant origin. Several studies, including animal and epidemiological investigations, have demonstrated that phenolic compounds in foods possess positive attributes such as anticarcinogenesis, antioxidant potential, antiviral activity, antimicrobial activity, and antimutagenic activity. However, other studies have shown that the same phenolics have negative attributes such as carcinogenic activity and antinutritional activity, as well as imparting negative attributes to foods. This review summarizes the information about food phenolics and presents the most current knowledge with respect to its role in human health, food attributes, and toxicity among others. 相似文献
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Food Phenolics, Pros and Cons: A Review 总被引:1,自引:0,他引:1
Phenolic compounds like simple phenols, flavonoids, and phenolic acids are commonly in foods of plant origin. Several studies, including animal and epidemiological investigations, have demonstrated that phenolic compounds in foods possess positive attributes such as anticarcinogenesis, antioxidant potential, antiviral activity, antimicrobial activity, and antimutagenic activity. However, other studies have shown that the same phenolics have negative attributes such as carcinogenic activity and antinutritional activity, as well as imparting negative attributes to foods. This review summarizes the information about food phenolics and presents the most current knowledge with respect to its role in human health, food attributes, and toxicity among others. 相似文献
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With the development of mobile technology, customer-centered co-design modularization (CCCM) has been studied by researchers and brand operators. In contrast, in the field of skirt design, CCCM on mobile application has been largely ignored. The purpose of this study is to develop a customer-centered co-design modularization on skirt that enables customers to co-design skirt on mobile application. On the basis of analytic hierarchy theory and interactive genetic algorithm, CCCM is consisted of two categories, such as skirt parts (design attributes) and communicating parts (behavior attributes). Skirt parts are determined by knowledge classification. Communicating parts are supported by recommending, consulting, evaluating among customers, consultant, and expert. The customer-centered co-design modularization was conducted and proved by a mathematical model. Compared to online shopping, the proposed CCCM is a good approach to involve stakeholders (customer, consultant, and expert) to design together who can communicate on mobile application. 相似文献
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Supradip Saha Nirmal K Hedau Vinay Mahajan Gyanendra Singh Hari S Gupta Anita Gahalain 《Journal of the science of food and agriculture》2010,90(2):239-244
BACKGROUND: Screening of natural biodiversity for their better quality attributes is of prime importance for quality breeding programmes. A set of 53 tomato genotypes was measured for their textural [skin firmness, pericarp thickness, total soluble solids (TSS)], nutritional [phosphorus (P), potassium (K), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn) and titrable acidity (TA)] and functional (β‐carotene, lycopene and ascorbic acid) quality attributes. RESULT: Three sets of data (textural, nutritional and functional attributes) were obtained and analysed for their mutual relationships. Wide variations were observed in most of the measurements, e.g. skin firmness (coefficient of variability (CV) 269‐612 g), pericarp thickness (CV 1.4–4.9 mm), potassium (CV 229–371 mg 100 g?1), iron (CV 611–1772 mg 100 g?1), ascorbic acid (CV 12–86 mg 100 g?1), suggesting that there are considerable levels of genetic diversity. Significant correlations (P < 0.05, 0.01) were also detected among different attributes of tomato genotypes, such as phosphorus and zinc with a correlation coefficient of 0.74, ascorbic acid and copper of 0.57, pericarp thickness and lycopene of ? 0.52. However, there were no correlations between textural and nutritional attributes. Five factors were computed by principal component analysis that explained 66% of the variation in the attributes, among which all micronutrients other than iron, TSS, firmness and β‐carotene were most important. Functional attributes except β‐carotene played a less important role in explaining total variation. CONCLUSION: This knowledge could aid in the efficient conservation of important parts of the agricultural biodiversity of India. These results are also potentially useful for tomato breeders working on the development of new varieties. Copyright © 2009 Society of Chemical Industry 相似文献
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The objective of this work was to identify the sensory attributes associated with the highest awards given to wines in large competitions. Data from the Mundus Vini annual wine competitions (editions) from 2014 to 2016 were used. The chemical analysis and sensory attributes were subjected to cluster analysis and logistic ridge regression to identify predictors of grand gold and gold medal awards. High ethanol levels and sugar concentrations, mainly in red wines, were observed. For both red and white wines, three clusters were identified which broadly separated grand gold from gold medal awarded wines. The discrimination of G wines was mainly due to higher scores of bitterness and green/vegetative characters in both red and white wines, and with barnyard attributes only in red wines. The prediction regression for white wines showed that the exotic fruit was the most valued sensory attribute along with the quality indicators of body and complexity. Red wines had a higher number of predictors, including positive attributes like dried fruits and spicy or negative attributes like green/vegetative and red berries. This study identified the most relevant sensory features most valued by competition jurors, which were broadly consistent with the so-called international commercial wine style. 相似文献
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贮藏条件与禽蛋品质的相关性研究 总被引:1,自引:0,他引:1
为了比较不同贮藏条件对禽蛋品质的影响,将鸡蛋、鸭蛋和鹅蛋置于5、10、20、30℃贮藏30d,分析3种禽蛋品质变化与贮藏条件相关性规律。结果表明:贮藏温度对禽蛋品质的影响显著,高温贮藏加速禽蛋品质下降;禽蛋品质随贮藏时间延长而下降;除哈夫单位,3种禽蛋品质可以用相同品质指标来衡量。拟合方程的判定系数表明,贮藏过程中失重率和整蛋pH变化可以用零级反应动力学方程表征,哈夫单位和蛋黄指数变化规律可以用一级反应动力学方程表征。品质变化动力学级数与禽蛋品种无关,不同种类禽蛋在贮藏过程中品质变化规律基本相似。 相似文献
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Maríaa del R. Moreira Alejandra G. Ponce Carlos E. Del Valle Sara I. Roura 《Journal of food science》2006,71(2):S188-S192
Heat shocks not only produced a reduction in the initial content of ascorbic acid but also affected the rate of degradation of ascorbic acid during refrigerated storage. Samples treated at higher temperatures presented faster rates of degradation. The heat shocks produced an initial reduction in the counts of mesophilic aerobic microorganisms, with greater reductions associated with the higher shock temperatures. However, high shock temperatures promoted faster microbial growths during storage, probably due to the liberation of nutrients by the disruption of membrane barriers. The sensory attributes of lettuce leaves subjected to heat shocks presented mixed results. Thermal treatments affected the enzymatic activity, reducing browning phenomena, but also caused deleterious effects on surface color and texture of lettuce leaves. Heat shocks of 50°C could be useful for short‐term preservation of minimally processed lettuce, where the high rate of metabolic processes cause great deterioration of fresh products. 相似文献
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Complex behavior of 33 commercial lotions was investigated in order to identify correlations between laboratory instrumental measurements and sensory attributes of these products. Sensory attributes were evaluated by trained panelists. Six attributes were identified as potentially related to rheology, which belong to three main sensory categories: appearance, pickup, and rub out. Potential rheological predictors were extracted from the data of rotational rheometry. Yield stress and instantaneous viscosity maximum (IVM) were determined in stress ramp. Alternative definitions of yield stress based on step‐shear and oscillatory strain sweeps were also considered along with linear viscoelastic moduli, G′ and G″. Statistical analysis has shown all these definitions of yield stress and IVM are in fact closely correlated and that IVM is the best overall predictor of most attributes although G′/G″ ratio also is significant for rub out attributes. However, integrity of shape, the main appearance attribute, is even better predicted by an imitative slump‐like test in which image analysis is used to quantify sample spreading on a flat surface. 相似文献
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This paper uses quality theory to identify opportunities for the meat sector that are consistent with trends in meat consumption. Meat consumption has increased and is likely to continue into the future. Growth is largely driven by white meats, with poultry in particular of increasing importance globally. The influence of factors such as income and price is likely decline over time so that other factors, such as quality, will become more important. Quality is complex and consumers' quality expectations may not align with experienced quality due to misconception of certain intrinsic cues. Establishing relevant and effective cues, based on extrinsic and credence attributes, could offer advantage on the marketplace. The use of extrinsic cues can help convey quality characteristics for eating quality, but also for more abstract attributes that reflect individual consumer concerns e.g. health/nutrition, and collective concerns, e.g. sustainability. However, attributes are not of equal value to all consumers. Thus consumer segmentation and production differentiation is needed. 相似文献