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91.
Marine activities have been increasingly competing for space and reducing areas for fishing. The use of spatially explicit tools can assist the decision making process on defining the optimal location of closures for fishing due to these emerging activities.This paper presents the Spatial Integrated bio-economic Model for FISHeries (SIMFISH). In this model fishers behaviour is simulated based on optimal effort allocation. The added value of this model compared to other existing spatial management tools lies in the presence of (i) short and long term fishers behaviour (ii) spatial explicit stock and fleet dynamics and (iii) relatively low data requirements.As an illustration, SIMFISH is applied in this paper to estimate the impact of area closures in the North Sea. Overall area closures have a negative impact on the profitability of the fleets. This would be worsened with higher fuel prices and decreased stock productivity.  相似文献   
92.
如今我国信息化技术全面发展,尤其对于工程测量工作领域来讲,不管是在工程建设和管理方面都产生不小的支撑引导效用。由此,笔者具体结合如今工程建设信息化测绘核心任何以及设备布置细节,进行结构整体安全管理周期和周边地理空间信息技术发展能效整理解析,试图将工程测量最新发展机遇和技术挑战问题处理完全。希望能够借此为日后一定时期范围内相关工程测量规划主体提供合理指导性建议内容,最终为我国各类工程事业可持续发展前景绽放奠定深刻适应基础。  相似文献   
93.
Model-based fault diagnosis tends to be too expensive or time-consuming to apply in the mineral processing industries, owing to the complexity and variability of operations. In contrast, data-based methods are inexpensive, but do not exploit the availability of first principle knowledge of plant operations. In this investigation, the use of process causality maps in conjunction with data-based fault diagnosis is considered as a hybrid methodology that can leverage the advantages of both approaches. Extreme learning machine algorithms are used to implement the data-based component of the approach. These algorithms can be deployed rapidly on large-scale systems and have the ability to deal with highly nonlinear systems. Two different variants are considered, viz. one used in combination with principal component analysis, as well as one with a bagging algorithm for fault diagnosis and applied to an industrial concentrator circuit in South Africa. The use of process causality maps led to significantly more effective fault diagnosis, while the use of extreme learning machines in combination with principal component analysis likewise allowed markedly better fault detection and diagnosis. In contrast, fault diagnosis with the bagging approach did not perform particularly well, owing to the high degree of correlation between the variables, which made it difficult to isolate individual causal variables.  相似文献   
94.
This paper addresses the multi-objective optimization problem arising in the operation of heat integrated batch plants, where makespan and utility consumption are the two conflicting objectives. A new continuous-time MILP formulation with general precedence variables is proposed to simultaneously handle decisions related to timing, product sequencing, heat exchanger matches (selected from a two-stage superstructure) and their heat loads. It features a complex set of timing constraints to synchronize heating and cooling tasks, derived from Generalized Disjunctive Programming. Through the solution of an industrial case study from a vegetable oil refinery, we show that major savings in utilities can be achieved while generating the set of Pareto optimal solutions through the ɛ-constraint method.  相似文献   
95.
Power generation characteristics of a sandwich‐type thermoelectric generator in which the heat source is embedded into thermoelectric elements are investigated. Our previous work on a similar concept only considered a uniform heat source distribution inside thermoelectric elements. In this work, the effect of the spatial distribution of a heat source is examined. In particular, the effect of the concentration of heat source near the one end, that is, the hot end, is intensively studied as a potential means of improving the efficiency of the device. Although the effects of heat source concentration in impractical cases without heat transfer limitations on the cold side remain ambiguous, it become clear that heat source concentration indeed has positive effects in more realistic cases with finite heat transfer coefficients imposed on the cold side. Because of the relatively low efficiency of typical thermoelectric generation, a significant amount of heat must be dissipated from the cold end of the thermoelectric element. Greater heat source concentration near the hot end leads to more effective utilization of available heat source, reduces the amount of heat rejected at the cold end, and lowers the hot end temperature of the thermoelectric element. Overall, it is suggested that heat source concentration can be used as a method to achieve more efficient operation and better structural integrity of the system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
96.
97.
采用不同通风量进行菇渣与猪粪高温共发酵,研究通风对发酵过程中堆体温度的时空变化的影响。结果表明,通风使堆体温度呈现出明显的梯度效应,不同处理各发酵时期的温度分布均由剖面中部向四周不断降低。高温区域的位置和面积随发酵时间呈动态变化规律,升温期温度在发酵罐中上部积聚,高温分布区类似椭圆形,高温期椭圆面积逐渐向堆体中部扩散和扩大,随后高温面积不断递减并向中下部迁移,降温期堆体各区域温度趋于一致。由等值线的疏密程度可知,温度的空间变异性大体呈现出高温期>第2次高温期>升温期>降温期的规律。结合试验各阶段的温度变化并考虑节能降耗,得出发酵升温期和高温期分别以0.05,0.067m3/(d·m3)进行通风,二次高温期与降温期以0.033 m3/(d·m3)进行通风条件最佳。  相似文献   
98.
The objective of this study was to investigate the impact of functional labelling on the consumers acceptability and purchase intentions of blueberry functional beverages (BFB). A 2‐day consumer acceptance test was conducted independently with functional information (n = 60) and without any information (n = 80). The presence of functional labelling did not influence the liking attributes of BFBs (P > 0.05). However, functional information positively affected consumer perception of health‐related perceptions associated with BFBs, such as ‘aiding eye health improvement’ and ‘eye fatigue relief’. Subjects perceived more health‐related perceptions when informed test was conducted. The first‐order effect was observed, in which the degree of the first‐order effect was greater for BFBs that had a thicker mouthfeel. Findings from the results can practically guide product developers and marketers in the functional drink industry by providing the strategy for how to evaluate reformulated functional beverages for the consumer acceptance test by warning a counter‐balanced sample presentation.  相似文献   
99.
论述了现有配电网自动化系统的基本特征、广义特征及发展中遇到的信息系统悖论问题,分析配电网自动化及其信息系统实施的必要条件,针对重庆城乡"二元化"结构提出因地制宜的实现方式和实用化条件,考虑了网络、设备、通道、投资、客户、运维等多方面因素,旨在基于现有理论和经验分析并避免配电网自动化应用中的典型误区。从自动化及相关系统的实施条件、实现方式和实用化等方面进行深入剖析,以新的角度重新认识配电网自动化,对技术、管理和理念等方面问题逐一解析,力图破解配电网自动化领域的信息系统悖论,最终加快实现配电运维水平大幅度提升。  相似文献   
100.
This paper reviews the literature related to the concept of information quality (IQ) in the context of the online environment to understand how it has been conceptualised in the Information Systems (IS) literature, to identify gaps in the literature, and to make recommendations for future research. This study also extends the Information Processing Model (IPM) and proposes a novel dynamic model of online IQ perceptions and impacts. To understand the online IQ construct, an in-depth review of the literature is conducted. Overall, we reviewed 508 journal articles published between 1995 and 2016. This study found that there is a substantial gap in the IS literature in regards to a full understanding of the online IQ construct and its relation with the IPM. More research is needed to understand the way individuals process and respond to online information. Further, although the importance of context in theory development has been emphasised in the literature, very few empirical articles have explored the impact of contextual factors on the IPM as well as perceived online IQ. The findings provide online vendors with important guidelines that should be considered to motivate individuals to acquire more information from their websites that could lead to more satisfied and loyal users.  相似文献   
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