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11.
Ángel García-Crespo Pedro Soto-Acosta Marcos Ruano-Mayoral 《Information Systems Management》2013,30(3):247-252
We empirically explored the implication of hard decisions in the context of the management of global software development (GSD) teams. We hypothesized and empirically tested our belief that hard decision making in conventional development projects is very similar to GSD and differences arise from the nature of the relationship and the ranking of issues. Findings from a Delphi study illustrated our approach and shed some light into the management of GSD teams. 相似文献
12.
Through the analysis of the existing theory and method of three-way decision,model of three-way decision based on the space of set pair information granule was proposed,which was to explain the intension and extension of three-way decision on the view of unity of opposites.Firstly the space structure of set pair information granule can be di-vided into positive granule,negative granule,different granule,which were similar and slightly different with three re-gions of generalized three-way decision.The three kinds of information granules in set pair information granule space were built based on certain positive degree,negative degree and different degree.Secondly,according to the given threshold,set pair information granule is divided into mutually disjointing positive region,negative region and different region.Based on these three regions,the computing method of decision loss function is put forward,and the process of decision-making algorithm is obtained use the three-way decision method of set pair information granule space to evalu-ate and make decision on risk investment,then good decision results have been achieved. 相似文献
13.
Accurate modeling of driver decisions in dilemma zones (DZ), where drivers are not sure whether to stop or go at the onset of yellow, can be used to increase safety at signalized intersections. This study utilized data obtained from two different driving simulator studies (VT-SCORES and NADS datasets) to investigate the possibility of developing accurate driver-decision prediction/classification models in DZ. Canonical discriminant analysis was used to construct the prediction models, and two timeframes were considered. The first timeframe used data collected during green immediately before the onset of yellow, and the second timeframe used data collected during the first three seconds after the onset of yellow. Signal protection algorithms could use the results of the prediction model during the first timeframe to decide the best time for ending the green signal, and could use the results of the prediction model during the first three seconds of yellow to extend the clearance interval. It was found that the discriminant model using data collected during the first three seconds of yellow was the most accurate, at 99% accuracy. It was also found that data collection should focus on variables that are related to speed, acceleration, time, and distance to intersection, as opposed to secondary variables, such as pavement conditions, since secondary variables did not significantly change the accuracy of the prediction models. The results reveal a promising possibility for incorporating the developed models in traffic-signal controllers to improve DZ-protection strategies. 相似文献
14.
Between 1954 and 1996, more than 200 nuclear power projects were publicly announced in the USA. Barely half of these projects were completed and generated power commercially. Existing research has highlighted a number of potential explanations for the varying siting outcomes of these projects, including contentious political protests, socioeconomic and political conditions within potential host communities, regulatory changes (‘ratcheting’), and cost overruns. However, questions remain about which of these factors, if any, had an impact on these outcomes. This article uses a new data set of 228 host communities where siting was attempted to illuminate the factors that led projects towards either completion or cancelation. Controlling for factors highlighted by past studies, we find that regulatory, site‐ and reactor‐specific factors predict the outcomes of attempts to site nuclear reactors over this time period. These findings have important implications in the post‐Fukushima ‘nuclear renaissance’ era when many still hope to revitalize the nuclear industry in the USA. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
15.
采用不同孔密度载体分别负载不同贵金属含量、不同涂层涂敷量制备系列三效催化剂,通过模拟计算和发动机台架试验研究了具有不同孔结构载体的催化剂性能.结果表明,提高载体孔密度可明显改善催化剂的起燃特性和空燃比特性、有效降低催化剂中贵金属用量、提高HCs转化效率.起燃温度变化取决于孔密度和贵金属含量间的协同作用;载体孔密度变化对... 相似文献
16.
提出了一种波导三路功分器结构,该功分器采用E面T型缝隙耦合结构来实现功分比的调节。通过调节耦合缝隙以及感性膜片,使输入阻抗匹配并且实现等功率同相位的三路功分输出。为了实现功率合成,采用对称的两个三路功分器进行背靠背级联实现功率合成网络,仿真结果显示出良好的驻波效果和极低的插损。最终对加工出的实物进行测量,在32.5~36 GHz频段内实现了输出功率幅度不平衡度小于0.5 dB的良好效果。通过背靠背连接两个功分器实现了在33.3~35.3 GHz带宽内插损小于0.3 dB的功率分配/合成网络。 相似文献
17.
18.
以双气缸三通换向阀为例,介绍了如何以最少的钢铁材料和最小的阀门体积,以及如何选用合适的材料和结构形式来进行三通阀设计. 相似文献
19.
In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons(HCs) by the water-gas shift(WGS) and the steam reforming(SR) reactions,respectively,especially at high temperatures.Meanwhile it is major component of the exhaust which can affect significantly the thermal stability of the three-way catalyst.Activity experiments were carried out close to the real operation conditions(GHSV,concentration,etc.) with a Pd/Ce0.67Zr0.33O2 catal... 相似文献
20.
This paper focuses on the subject of concurrent delay from a general contractor (GC)-subcontractor perspective. When there is a concurrent delay by multiple subcontractors, or between the GC and other subcontractor(s), there has not been a uniform approach as to how the liquidated damages are apportioned. Previous research seems to ignore this issue. This paper first reviews some relevant court cases. Using a warehouse project as a case study, it then examines different practices that the GC could take in apportioning damages of concurrent delays to both himself/herself as well as to the responsible subcontractors. Results are very inconsistent between and within the apportionment practices. This supports an alternative hypothesis that apportionment is an important issue. Practitioners should specify which apportionment practice will be used and under what circumstances it will be applied in their subcontracts. Researchers may develop a more consistent and reliable approach for this type of apportionment. 相似文献