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21.
A critical presentation of the moisture diffusivity estimation methods in the field of solids drying is attempted. Methods are classified, discussed, and tabulated with corresponding references. Each particular method is briefly described and discussed in terms of its simplicity, accuracy of moisture diffusivity prediction, and applicability to various materials  相似文献   
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Maintainability analysis stands today where reliability was ten years ago. Many and varying definitions of maintainability have been proposed; many mathematical approaches to maintainability and its various aspects have been pursued. Nevertheless, there is presently no general agreement on the definition of maintainability or on the technique of its quantification. In addition, there is insufficient meaningful maintainability field and laboratory data. As in the case of reliability, analytical techniques are only a part of the maintainability improvement effort. There is a need for improvement in both the design of the total maintenance system as well as analytical techniques for its evaluation.  相似文献   
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Increased child abuse in families with twins   总被引:1,自引:0,他引:1  
Close spacing of children may be a significant risk factor for subsequent abuse in some families. Twin births are an extreme example of close spacing. Therefore, the authors hypothesized that twin births may predispose to an increased incidence of child abuse. Thirty-eight families with twins were compared with 97 single birth families and matched for birthdate, maternal age, race, and socioeconomic status. Families with twins experienced a significantly higher incidence of child abuse and neglect than did those with single births (p less than .003). A written questionnaire designed to study mothers' feelings and perceptions of support systems showed a significant difference only in greater difficulty in feeding twins as compared with single infants (p less than .001). Mothers of abused children were more likely not to answer the questionnaire at all (p less than .005). Neither mothers of single births nor those of twins felt that health professionals provided adequate education or support following the birth of their infants.  相似文献   
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Gridding microarray images remains, at present, a major bottleneck. It requires human intervention which causes variations of the gene expression results. In this paper, an original and fully automatic approach for accurately locating a distorted grid structure in a microarray image is presented. The gridding process is expressed as an optimization problem which is solved by using a genetic algorithm (GA). The GA determines the line-segments constituting the grid structure. The proposed method has been compared with existing software tools as well as with a recently published technique. For this purpose, several real and artificial microarray images containing more than one million spots have been used. The outcome has shown that the accuracy of the proposed method achieves the high value of 94% and it outperforms the existing approaches. It is also noise-resistant and yields excellent results even under adverse conditions such as arbitrary grid rotations, and the appearance of various spot sizes.  相似文献   
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Multi-objective optimization of a trigeneration plant   总被引:1,自引:0,他引:1  
A multi-objective optimization method was developed for the design of trigeneration plants. The optimization is carried out on technical, economical, energetic and environmental performance indicators in a multi-objective optimization framework. Both construction (equipment sizes) and discrete operational (pricing tariff schemes and operational strategy) variables were optimized based on realistic conditions. The problem is solved using a multi-objective evolutionary algorithm. An example of a trigeneration system in a 300 bed hospital was studied in detail in order to demonstrate the design procedure, the economic and energetic performance of the plant, as well as the effectiveness of the proposed approach even under fluctuating energy prices.  相似文献   
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A 69-year-old man showed gradually developing thoracoabdominal aortic aneurysm (TAAA) after coronary artery bypass grafting. The patient underwent graft replacement of TAAA uneventfully under partial cardiopulmonary bypass with selective perfusion of major abdominal branches. The major abdominal branches and two pairs of intercostal arteries were reconstructed. The patient showed no organ failure or spinal damage postoperatively. Partial cardiopulmonary bypass with selective perfusion of abdominal branches successfully protected both the visceral organs and the spinal cord from ischemia in a TAAA surgery.  相似文献   
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