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排序方式: 共有1369条查询结果,搜索用时 11 毫秒
61.
Food selection at a particular occasion is guided by properties of the food itself (sensory or intrinsic properties), but also by the information provided with the food, for example, packaging information (extrinsic properties). We compared preference responses of 71 consumers with a considerable type 2 diabetes risk, who had undergone nutrition counseling in a prevention program, in sensory assessments and product evaluation integrated into Adaptive Conjoint Analysis with the response of a healthy control group (n = 101). Vanilla yogurt, varied in composition (fat content, sugar content, flavor intensity) and packaging information (fat content, sugar content, flavor intensity), was used as stimulus material. Both groups of consumers preferred yogurt with a higher fat content on the basis of sensory evaluation, but rejected products with a higher fat content (10 g/100 g) when this information was available on the package. The degree of rejection was significantly higher for the high risk group. Whereas both groups preferred reduced-sugar yogurt on the basis of declaration, preferences towards the less sweet product were only observed for the high risk group. 相似文献
62.
Mahsa Majzoobi Fatemeh Ghiasi Asgar Farahnaky 《International Journal of Food Science & Technology》2016,51(1):78-86
Wheat germ is an available and economical source of protein, vitamins and antioxidants with an increasing application in food products. The main aim of this study was to investigate the effects of different levels (0.0, 2.5, 5.0, 7.5 and 10.0%) and particle sizes (120, 210 and 354 μm) of wheat germ on physicochemical properties of fresh chilled dairy dessert. With increasing wheat germ level, dry matter of the dessert increased while the pH decreased. Particle size had no significant effect on these parameters. Increasing the wheat germ content and particle size enhanced darkness, hardness, cohesiveness and gumminess of the desserts while decreasing springiness and water release of the samples. Wheat germ level had greater effects on different quality aspects of the desserts than its particle size. The most acceptable dessert was produced with no more than 5.0% wheat germ with either of the particle sizes used in this study. 相似文献
63.
《Egyptian Journal of Petroleum》2015,24(2):119-130
The determination of the most unstable areas in oil fields is critical for addressing engineering problems of wellbore and sand production as well as geologic problems such as understanding dynamic constraints on hydrocarbon migration and fracture permeability. In this research work, coherency seismic attribute has been used for the determination of the most critical areas in terms of drilling stabilities in the DQ oil field, Iran. The results obtained have shown that the (1) predominant features are the SSE–NNW and N–S trends (2) the central part of the DQ structure shows the highest concentration of segment bundles, (3) the segment bundles seem to be aligned along some lineaments oriented SE–NW and SSE–NNW, and (4) on the eastern and western margins of the map there is an anomalous concentration of segments oriented E–W. It can be concluded that coherency attribute is a valuable tool for structural analysis highlighting those areas containing unstable features. 相似文献
64.
Jin‐Hong Zhao Rui Hu Hong‐Wei Xiao Yang Yang Fang Liu Zhi‐Lin Gan Yuan‐Ying Ni 《International Journal of Food Science & Technology》2014,49(4):960-968
The effect of osmotic dehydration pretreatment on the quality attributes (e.g. colour, hardness, drip loss, vitamin C content and pH) of frozen mango cuboids in different osmotic solutions (sucrose, glucose and maltose) and concentrations (30, 45 and 60% (wt/wt)) was investigated. Results revealed that melting temperature of mango cuboids was affected by both solute type and solid mass fraction. In addition, the dehydrofrozen samples pretreated in maltose had higher quality in vitamin C content (increasing by 23.5–73.0%), colour (colour change reducing by 2.6–39.2%) and drip loss (reducing by 0.7–9.7%) than those pretreated in other osmotic solutions. The cuboids pretreated in glucose displayed higher hardness (increasing by 16.4–36.2%). Based on principal component analysis and group distance, osmotic dehydration in 45% maltose was proposed as the most favourable freezing conditions with the highest sensory score (6.8). The current work indicates osmotic dehydration significantly improves frozen mango quality. 相似文献
65.
Jiewu Leng 《国际生产研究杂志》2018,56(15):5131-5146
Evaluation on collaborative manufacturing network (CMN) structure characteristics has important implications for network operations such as production decision-making, product recovery, creating consensus. Several recent studies suggest that augmenting network structure with nodes’ attributes can provide a more fine-grained understanding of the network. However, there have been few studies to provide a systematic understanding of these effects in a CMN at scale. This gap is bridged using an industrial printing machinery CMN data-set collected on a web-based producing and outsourcing service platform. Novel phenomena with respect to both interaction and attribute metrics across and within the CMNs are observed. Moreover, although many studies employ either interaction or attribute data to study the relative roles of manufacturers in a CMN, relatively little is known about the relationship between these two types of data. This study explores this relationship by comparing two defined metrics (i.e. relational capability and node capability), which evaluate the manufacturers’ interactions and attributes, respectively. We examine to what extent the two metrics of manufacturers correlate with each other, and how possible dissimilarities and similarities can be explained based on the collected industrial CMN data-set. The insights thereby provide a better basis for efficient operations decision-making in CMN. 相似文献
66.
Ashkan Javaherian Amir Movafeghi Reza Faghihi Effat Yahaghi 《Journal of Visual Communication and Image Representation》2013,24(7):773-785
This study proposes a versatile criterion for estimating quality of images in electrical impedance tomography. The point spread function (PSF) is calculated throughout the domain based on the scattering of energy as responses to a small anomaly spirally moved from the centre to the boundary. The proposed PSF is a measure of weighted spatial variance (WSV) of the conductivity over the whole domain. For each element, the weighting factor is a normalized multiplication of the area of that element by its square intensity. The WSV collectively incorporates all image attributes, i.e., spatial resolution, artifact, amplitude response, positioning error and shape deformation. The location of artifacts, which significantly influences reconstructed images in reality, is taken into account as well. The results illustrate that the proposed measure is more tolerant than existing criteria in evaluating performance of EIT systems in both theory and practice. 相似文献
67.
68.
In economic terminology, ‘competition intensity’ can be used to mirror to a certain degree the status of industrial competition in a specific market, while in the construction market, it particularly involves the part of project competition intensity (PCI). Based on a road project in China, two forms of PCI, overt and covert, are identified in this study. To lower project construction cost thus enabling better project tendering performance, clients can facilitate higher levels of overt PCI by tailoring their tendering procedures, whereas, through covert PCI project competitors can adopt anti‐competitive behaviours to attain the expected works. The difference between overt PCI and covert PCI indicates various practitioners' perspectives and impact on the levels of competition intensity in construction. The findings suggest a way to promote PCI studies in the future, and offer new insights into other parts of competition intensity in construction. 相似文献
69.
基于粗糙集的案例属性约简技术 总被引:1,自引:0,他引:1
为了提高案例推理(case-based reasoning,CBR)系统的案例匹配效率,引入粗糙集理论对案例属性约简技术加以研究.提出准约简的概念,依次证明了某一条件属性集成为准约简与准约简成为约简的充要条件.进而,以核为出发点,提出了一种改进的基于分辨矩阵的属性最小约简算法.为使之仍然适用于连续属性,提出一种基于逼近精度敏感性的离散化算法.最后,将此约简技术应用于某钢铁企业的实际动态调度问题中,计算试验表明,该技术消除了冗余信息,提高了案例匹配的效率. 相似文献
70.
针对目前岩爆倾向性中预测模型权重确定存在不足导致模型精度不高的现状,为更准确地预测岩爆倾向性,提出综合运用粗糙集理论中的代数观和信息观,确定属性最优权重,并修正岩爆倾向性与评价指标之间的关系,建立岩爆等级理想点矩阵。根据岩爆发生条件,选取岩石脆性指数、切应力指标和弹性应变能指数3项指标作为岩爆判别指标,以国内外20组典型岩爆数据为样本,建立改进的粗糙集—理想点法(RS-TOPSIS)岩爆倾向性预测模型,并应用该模型对玲珑金矿等工程实际进行了岩爆倾向性预测。结果表明:改进后样本预测精度相比于改进前有了显著提高,所建立的模型对实际工程的岩爆倾向性预测效果良好,预测结果更准确。 相似文献