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排序方式: 共有2760条查询结果,搜索用时 15 毫秒
111.
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
112.
According to the Ghana Statistical Service, construction activity generated US$3.8 billion in 2014, representing about 12.7% of nominal GDP. A key factor that most investors in the construction sector consider in project selection is cost which has escalated over the years. Therefore, we examine the co-movements and causality in the time and frequency domains between the prime building cost index (PBCI) and its disaggregates on one hand and inflation and exchange rate on the other hand in Ghana. The findings revealed that the degree of co-movement between PBCI and inflation was significant at the 5% level and occurred over the long-run, indicating that construction cost drives inflation. The degree of co-movement between the prime build cost index and exchange rate occurred within the short term. These co-movements have policy implications for substituting inflation and exchange rates in project costing by investors in Ghana. The co-movement between the PBCI and inflation in the medium to higher frequencies suggests that inflation risk-averse investors should consider short-term projects. Again, the short to medium frequency co-movements between the PBCI and exchange rate indicates that investors should consider exchange rate risk in long-term projects. 相似文献
113.
Wenjie Bi 《国际生产研究杂志》2017,55(12):3331-3348
Inspired by the latest empirical studies, we propose a new updating model for reference prices by assuming that consumers’ memories are limited and their recall of previous prices obeys a first-order Markov stochastic process. We investigate a dynamic pricing model with stochastic reference effects and finite memory. Consistent with the exponential smoothing model, we indicate that reference effects lead to monotonic convergence of the optimal price path to an expected steady-state price. The steady-state range tends to widen as consumers become loss-averse. The results of our numerical experiments differ from findings of certain models under the assumption of stochastic recall memory of consumers. The optimal price path fluctuates consistently around the steady state instead of remaining constant. The effect of the first price on the memory window and long-term profits decreases as the length of memory window increases. 相似文献
114.
Mass customisation systems have been well-established in the fashion industry. Some fashion brands offer the mass customisation system for their selected seasonal products, and allow unconditional returns and full refund for any unsatisfied customers. Motivated by the above mentioned observed industrial practice and based on the growing importance of responsive supply, we explore in this paper the value of quick response supply in fashion mass customisation systems with consumer returns. We focus on investigating how the consumer returns rate affects (i) the optimal inventory decision of the fashion brand, (ii) the achievability of Pareto improvement in implementing quick response supply, (iii) the respective values of quick response for the fashion brand, the fashion supplier and also the fashion supply chain, and (iv) the impact of quick response supply on the environment. We interestingly find that consumer returns enhance the value of quick response supply to the fashion supplier. Quick response supply is also found to be helpful in reducing the environmental cost under the fashion mass customisation system with consumer returns. 相似文献
115.
《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
116.
针对在传统的客户流失预测数据预处理中,使用one-hot编码处理离散属性导致数据维度增加及数据过于稀疏的问题,提出了两种基于多层感知机的改进后的客户流失预测模型。其主要思想是分别使用堆叠自编码器和实体嵌入两种方法对多层感知机进行改进,通过将离散属性的高维编码数据向低维空间映射,有效地减少了one-hot编码产生的稀疏数据,增加了离散属性值之间的关联度。在对两份公开的数据集进行交叉验证后的实验结果表明,改进后的模型既有效地提高了预测的准确度,又维持了传统多层感知机模型在并行化计算方面的优势。 相似文献
117.
118.
《Journal of dairy science》2019,102(10):8807-8818
A series of food safety incidents related to domestically produced dairy in China harmed consumer confidence and caused a dramatic decrease in dairy consumption from 2008 to 2010. Compared with previous studies that mainly assessed consumer confidence in food or dairy in general, this study focused on 2 specific dairy products, milk and infant milk formula (IMF). Based on data from 934 Chinese consumers, confidence in the safety of milk and IMF was measured by using a multi-item scale with 2 dimensions—optimism and pessimism. We found that Chinese consumers were optimistic about the safety of milk and IMF but, at the same time, were concerned about the risks related to milk and IMF. Chinese consumers have less confidence in IMF than in milk. Structural equation modeling indicated that consumer trust in manufacturers and third parties in the dairy supply chain and confidence in other foods, such as meat and fish, can foster consumer confidence in the safety of milk and IMF, while the extent of recall of the melamine infant formula incident in 2008 and trait worry exert negative effects. In addition, consumers with more children or less family income are likely to be more confident in domestically produced IMF. These insights into consumer confidence and its determinants can assist dairy supply chains and regulatory institutions in formulating effective risk communication strategies to strengthen consumer confidence. 相似文献
119.
食品安全在企业财务绩效中的功能作用及实现路径 总被引:1,自引:0,他引:1
食品企业所具有的食品安全保障能力,必然促使其利益相关方作出能够影响企业利益的行为选择,最终通过企业的财务绩效反映出来。通过对食品安全在企业财务绩效中功能的审视,可以发现食品安全通过影响消费者、政府以及社会舆论等利益相关者对其产品的态度,能够对其财务绩效起到相应的提升作用。因此,财务绩效具有促进食品企业履行食品安全保障责任的功能。然而,由于诸多因素的影响,财务绩效促进企业履行食品安全保障责任的功能可能出现失范。这些因素包括短期绩效和长期绩效之间的矛盾、信息披露制度欠缺,以及食品企业社会责任意识缺失等。因此有必要通过相应的路径,采取针对性的措施,以构建财务绩效促进食品企业履行食品安全保障责任功能的机制。 相似文献
120.