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1.
Meeting time and cost objectives in complex projects involves specific problems and risks. An attempt is made to analyse the components of total cost increase of a project caused by time delay. An outline is given as to how these considerations can be used to estimate cost increases in investors' decision situations as well as to ascertain fair contractual penalties and claims for compensation and for the evaluation of justified project acceleration costs.  相似文献   
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Physical principles governing mine ventilation systems and state of the art ventilation modeling are initially outlined. Several computer programs for modeling the mine ventilation-mine fire interaction, which were developed during the last decade, are then described. An older program considers fires and ventilation systems as going through a sequence of steady state conditions. Airflow rates, pressure losses, temperatures, fume and methane concentrations can be determined. Newer programs allow transient state fume concentration calculations under the assumption of constant airflow rates as well as the determination of fume exposures of escaping miners. Recent work attempts the complete transient state simulation of fires and all ventilation properties.  相似文献   
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Topics in Catalysis - This paper presents the results of a quantitatively substantiated “expert judgement” concerning the potential for further reduction of the exhaust emissions of...  相似文献   
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We have found experimentally that rf SQUID's working in a nonhysteretic mode with small critical currents give exactly at resonance and at very low rf bias a triangular pattern with a period equal to half of one elementary quantum of magnetic flux. We discuss a possible explanation of this peculiar result.  相似文献   
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This study examined (a) the role of avoidance coping in prospectively generating both chronic and acute life stressors and (b) the stress-generating role of avoidance coping as a prospective link to future depressive symptoms. Participants were 1,211 late-middle-aged individuals (500 women and 711 men) assessed 3 times over a 10-year period. As predicted, baseline avoidance coping was prospectively associated with both more chronic and more acute life stressors 4 years later. Furthermore, as predicted, these intervening life stressors linked baseline avoidance coping and depressive symptoms 10 years later, controlling for the influence of initial depressive symptoms. These findings broaden knowledge about the stress-generation process and elucidate a key mechanism through which avoidance coping is linked to depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Replicates and extends the work of R. H. Moos and S. R. Clemes (see record 1967-07395-001) and F. van der Veen (see record 1965-08090-001). Each of 6 patients saw each of 4 therapists twice. The variables total activity, feeling words, action words, reinforcements each was scored separately for patient and therapist for each interview. Patient problem expression and therapist accurate empathy were rated for each interview. Consistent differences between patients accounted for substantially more variance than consistent differences between therapists on all variables. Patient * Therapist * Session interactions generally accounted for large proportions of the total variance. Results indicate that the therapist behaviors studied were not the result of a trait, of a given tendency to be empathic, or of a consistently applied therapeutic technique, but rather were very substantially situationally or patient determined. (23 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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