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21.
Nathan M. Wilbur Antin M. O'Sullivan Kerry T. B. MacQuarrie Tommi Linnansaari R. Allen Curry 《河流研究与利用》2020,36(5):769-783
Anthropogenic influences, including climate change, are increasing river temperatures in northern and temperate regions and threatening the thermal habitats of native salmonids. When river temperatures exceed the tolerance levels of brook trout and Atlantic salmon, individuals exhibit behavioural thermoregulation by seeking out cold‐water refugia – often created by tributaries and groundwater discharge. Thermal infrared (TIR) imagery was used to map cold‐water anomalies along a 53 km reach of the Cains River, New Brunswick. Trout and salmon parr did not use all identified thermal anomalies as refugia during higher river temperature periods (>21°C). Most small‐bodied trout (8–30 cm) were observed in 80% of the thermal anomalies sampled. Large‐bodied trout (>35 cm) required a more specific set of physical habitat conditions for suitable refugia, that is, 100% of observed large trout used 30% of the anomalies sampled and required water depths >65 cm within or adjacent to the anomaly. Densities of trout were significantly higher within anomalies compared with areas of ambient river temperature. Salmon parr were less aligned with thermal anomalies at the observed temperatures, that is, 59% were found in 65% of the sampled anomalies; and densities were not significantly different within/ outside anomalies. Salmon parr appeared to aggregate at 27°C, and after several events over 27°C variability in aggregation behaviour was observed – some fish aggregated at 25°C, others did not. We stipulate this is due to variances of thermal fatigue. Habitat suitability curves were developed for velocity, temperature, depth, substrate, and deep water availability to characterize conditions preferred by fish during high‐temperature events. These findings are useful for managers as our climate warms, and can potentially be used as a tool to help conserve and enhance thermal refugia for brook trout and Atlantic salmon in similar systems. 相似文献
22.
In the retail industry, backroom inventories are typically associated with higher labor costs and greater operational complexity. Thus, retailers look for ways to eliminate backroom inventories. A heuristic used for this purpose is the pack‐and‐a‐half rule which suggests that the shelf space allocated for a product should be at least 50% larger than the case pack quantity in which the product is delivered. Despite its popularity among retailers, the pack‐and‐a‐half rule has been ignored in the academic literature. We introduce the pack‐and‐a‐half rule, assess its impact on a retailer's profits, identify cost, demand, and product characteristics driving this impact, and propose a modification. Based on an analysis of data obtained from a retailer on 1,986 SKUs in 20 categories, we find that the pack‐and‐a‐half rule decreases a retailer's profits, on average, by 10% when applied uniformly across all SKUs. Further, this decrease is significantly affected by product depth, product width, demand elasticity, case pack quantity, and inventory carrying cost. Finally, we develop a set of modifications based on these variables where the pack‐and‐a‐half rule is applied selectively and in a stepwise fashion. These modifications limit the decrease in a retailer's profits to a range between 6% and 7%. 相似文献
23.
Remko van Hoek 《Journal of Purchasing & Supply Management》2021,27(3):100688
PSM has played an important role in the initial mitigation of risks caused by the COVID-19 pandemic. We explore the nature and scope of this role and develop a roadmap for PSM contributions towards greater supply chain resilience. We find that the role of PSM is (1) multidimensional; responding to supply risks but also to demand and logistics risks, (2) counter to game theory; collaboration increased instead of decrease, (3) multi-stage; beyond the initial response the hardest change efforts are still ahead. The pandemic is accelerating the journey towards future-proof PSM but not necessarily revolutionizing the future of PSM. 相似文献
24.
25.
Lake Chivero: A management case study 总被引:1,自引:0,他引:1
C. H. D. Magadza 《Lakes & Reservoirs: Research and Management》2003,8(2):69-81
Lake Chivero in Zimbabwe was shown to be hypereutrophic. Historical data showed that the eutrophication process had been arrested in the late 1970s. However, a combination of poor planning, multiplicity of jurisdiction, mismatch between rate of urbanization and waste management investment, recent changes in the local climate and a permissive, immature political system that called for no public accountability resulted in environmental management breakdown leading to hypereutrophication of the lake. The case of Lake Chivero is presented as an example of a wider global issue regarding the status of environmental management in competition with other priorities in emerging democracies. 相似文献
26.
建筑企业实施供应链管理的关键因素 总被引:9,自引:0,他引:9
首先介绍了建筑企业实施供应链管理的必要性,然后分析了建筑供应链的特征,在此基础上论述了建筑企业实施供应链管理的九个关键成功因素,从而为建筑企业有效实施供应链管理提供依据。 相似文献
27.
Synopsis In contrast to the neoclassical economic presumption in favor of markets, we argue that organizations, not markets should be taken as our default assumption. We do so on information processing grounds. We distinguish between Zen and market Knowledge. The first is embodied and hard to articulate and the second abstract-symbolic. In human evolution, the first type of knowledge came first, and, on any pragmatic definition of knowledge, it still incorporates most of what we mean by the term. We take codification and abstraction as the two data processing activities that lead to the articulation of knowledge into an abstract-symbolic form. We develop a conceptual framework, the Information-Space (I-Space) to show how far the articulation of knowledge leads to its being shared. Whereas an unlimited sharing of information and knowledge leads to market-oriented outcomes, a more limited sharing leads to organizational outcomes. A market-oriented economics has tended to look to physics for its models; the field of organization theory has tended to look to biology. A more organization-oriented economics would thus look more to biology for its models. 相似文献
28.
福建周宁水电站工程由闽东水电开发有限公司负责项目管理。该项目严格按照《招投标法》进行工程和设备的招标,进行了多项设计优化,注重工程质量和安全文明生产,积极开展达标投产工作,实现了进度快、质量优、投资省、效益好的管理目标。 相似文献
29.
30.
We examine the association between abnormal returns and earnings management in the context of price control regulations to test the construct validity of the earnings management model. Abnormal returns are used as a market–based measure, and discretionary accruals are employed to measure earnings management. Our results support the hypotheses that (1) price control regulations affect firms' security prices negatively, (2) firms make income–decreasing discretionary accruals to increase the likelihood of price increase approval, and (3) firms that are affected most negatively by the regulations manage earnings more aggressively. We conclude that the earnings management model we use in this study is capable of predicting opportunistic discretionary accruals. 相似文献