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ABSTRACT Management controls can be divided into two types that can have opposite effects on organizational learning: behavioral controls, which promote efficiency but also stifle much of the learning opportunity, and outcome controls, which foster interaction among stakeholders can add to the learning environment. This article reports on a study that confirms these observations and explores the nature of their direct and indirect influences on project performance. Data from a sample of software development professionals confirms that behavioral controls and learning directly influence project performance, while outcome controls contribute only indirectly through their impact on learning. 相似文献
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Abstract A preliminary investigation of the role of look-ahead in one-person games is presented. The use of look-ahead in comparing the effectiveness of different heuristic functions is discussed. There is a survey of recent work in tree-searching including that of Doran and Michie [4], Hart, Nilsson, and Raphael [7] and Pohl [17]–[19]. Based on some of Pohl's results, two theorems are proven in Section 2. These suggest a possible use for look-ahead. Some experimental results are presented in Section 3 which satisfy to a limited degree the aforementioned theorems, and some additional observations are made. In conclusion, an attempt is presented to relate look-ahead to the notion of “informedness” introduced by Hart, Nilsson, and Raphael. Finally, some further directions for research are suggested. 相似文献
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Jung-Jae Park Min-Wook Lee Sam S. Yoon Ho-Young Kim Scott C. James Stephen D. Heister Sanjeev Chandra Woon-Ha Yoon Dong-Soo Park Jungho Ryu 《Journal of Thermal Spray Technology》2011,20(3):514-522
Characteristics of supersonic flow are examined with specific regard to nano-particle thin-film coating. Effects of shockwaves, nozzle geometry, chamber pressure, and substrate location were studied computationally. Shockwaves are minimized to reduce fluctuations in flow properties at the discontinuities across diamond shock structures. Nozzle geometry was adjusted to ensure optimal expansion (i.e., P exit = P ambient), where shock formation was significantly reduced and flow kinetic energy maximized. When the ambient pressure was reduced from 1 to 0.01316 bar, the nozzle’s diverging angle must be increased to yield the optimum condition of minimized adversed effects. Beyond some critical distance, substrate location did not seem to be a sensitive parameter on flow characteristics when P amb = 0.01316 bar; however, overly close proximity to the nozzle exit caused flow disturbances inside the nozzle, thereby adversely affecting coating gas flow. 相似文献
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Self-heating of sulphides poses safety, environmental and economic concerns to the mining and metallurgical industries, especially when sulphide ores or concentrates have to be stored or transported. The first target of this investigation is the self-heating of pyrrhotite (Po), the most commonly suspected mineral to trigger the phenomenon because of its fast oxidation in moist air. Following a standard experimental protocol, self-heating was assessed on samples of Po mixed with sand as an inert material. With increasing Po content, self-heating rates progressively increased but the samples visually appeared less and less oxidized. A high Po content, it was hypothesized, may give a more reducing environment favouring formation of hydrogen sulphide (H2S). The presence of this gas could be significant for self-heating for several reasons which are discussed. The hypothesis was tested by including copper pieces to detect the gas by forming copper sulphide, and adding copper sulphate in excess which suppressed self-heating, apparently by reacting with and removing the gas. 相似文献
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