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21.
The multi‐dimensional effort in the pursuit of excellence in engineering education at Kuwait University is described. The engineering program curricula have continuously been modified to provide engineering students with an intellectual foundation that is broad, well‐rounded, and multi‐disciplinary. He pursuit of excellence in engineering education has earned the College ABET's “substantial equivalency” rating for six of its programs. Women constitute more than forty percent of the incoming engineering student body in recent years. A comprehensive questionnaire survey of the alumni of the College of Engineering was performed. Nearly all of engineering women alumnae are presently employed and a majority feel that the education and training, which they received from the engineering programs, were excellent and responsive to the needs of their jobs. A clear majority of women alumnae also feel equal (or even superior), to their male counterparts with regard to job‐related factors. The feeling of equality is positively and significantly correlated with GPA, field of specialization, and years of experience.  相似文献   
22.
Shrinkage of repair material, especially in patching repairs, is the major factor inducing cracking in concrete repairs. Induced cracks in repair materials are due to restrained shrinkage. Although in usual practice, the free shrinkage of the repair mortar is measured, in reality, cracking is not due to free shrinkage. It is well known that cracking is due to restrained shrinkage. It is very hard to measure the restrained shrinkage; therefore, to overcome this problem a restraint factor (R) is used to modify the free shrinkage and come up with the restrained shrinkage. The restraint factor is influenced by the surface and boundary condition.In this study, the restraint factor for patching repair with different boundary conditions (with eaves and without eaves) and surface condition (rough and smooth) of the substrate concrete is investigated.The results show that the restraint factor R lies between 0.1 and 0.94; with an increase of restraint, the restraint factor is increased. In situations with a high level of restraint (eaves at the perimeter and a rough surface of substrate), the average R is 0.83. while with a low level of restraint (without eaves at the perimeter and a smooth surface of the substrate), the average R is 0.22.  相似文献   
23.
Bulletin of Engineering Geology and the Environment - Understanding the physical and especially mechanical properties of forest soils is very important in forest engineering operations including...  相似文献   
24.
In this paper, a more general version of the flow shop scheduling problem with the objective of minimizing the total flow time is investigated. In order to get closer to the actual conditions of the problem, some realistic assumptions including non-permutation scheduling, learning effect, multiple availability constraints, and release times are considered. It is assumed that the real processing time of each job on a machine depends on the position of that job in the sequence, and after processing a specified number of jobs at each machine, an unavailability period is occurring because of maintenance activities. Moreover, it is supposed that each job may not be ready for processing at time zero and may have a release time. According to these assumptions, a new mixed integer linear programming (MILP) model is proposed to formulate the problem. Due to the high complexity of the problem, a heuristic method and a simulated annealing algorithm are presented to find the nearly optimal solutions for medium- and large-sized problems. To obtain better and more robust solutions, the Taguchi method is used in order to calibrate the simulated annealing algorithm parameters. Finally, the computational results are provided for evaluating the performance and effectiveness of the proposed solution methods.  相似文献   
25.
ABSTRACT

The phase behaviour of heavy oil mixtures was studied using an X-ray imaging system. Batch phase experiments were performed at temperatures and pressures up to 725 K and 7 MPa. Complex phase behaviour such as liquid-liquid-vapour and solid-liquid-liquid-vapour were observed and preliminary experimental phase diagrams were constructed. This observed complex phase behaviour is consistent with thermodynamic theory and such phase behaviour can be modelled using the Peng-Robinson equation of state and the tangent plane criterion. These latter points are illustrated through the phase diagram for a model reservoir fluid (ethane + propane + n-butane + phenanthrene) which exhibits solid-liquid-liquid-vapour phase behaviour. Example predicted and experimental phase diagrams are presented for this model system.  相似文献   
26.
In real-world assembly lines, that the size of the product is large (e.g., automotive industry), usually there are multi-manned workstations where a group of workers simultaneously perform different operations on the same individual product. This paper presents a mixed integer programming model to solve the balancing problem of the multi-manned assembly lines optimally. This model minimizes the total number of workers on the line as the first objective and the number of opened multi-manned workstations as the second one. Since this problem is well known as NP (nondeterministic polynomial-time)-hard, a heuristic approach based on the ant colony optimization approach is developed to solve the medium- and large-size scales of this problem. In the proposed algorithm, each ant tries to allocate given tasks to multi-manned workstations in order to build a balancing solution for the assembly line balancing problems by considering the precedence relations, multi-manned assembly line configuration, task times, and cycle time constraints. Through computational experiments, the performance of the proposed ACO is compared with some existing heuristic on various problem instances. The experimental results validate the effectiveness and efficiency of the proposed algorithm.  相似文献   
27.
Host-specific probiotics have been used to control enteric pathogens, including foodborne pathogens, in food animal production. However, evaluation of the efficacy of these probiotics requires costly in vivo assays in the target animal. The nematode Caenorhabditis elegans has been used for prescreening of antimicrobial agents and for studies of host-pathogen interactions. In the present study, 17 Lactobacillus isolates from chicken and pig intestines were tested with C. elegans, and the ability of these isolates to prevent death from Salmonella infection was variable. Two Lactobacillus isolates (S64, which gave full protection, and CL11, which gave no protection) were further studied. Both isolates exhibited a similar colonization profile in the C. elegans intestine. Although different culture fractions of CL11 were not protective, both live and heat-killed S64 cells provided full or partial protection of C. elegans from death caused by Salmonella infection. In contrast, different culture fractions from both isolates had similar effects on the colonization of the nematode intestine by Salmonella Typhimurium DT104. Our preliminary results from a pig performance trial revealed a correlation between the degree of protection in the C. elegans survival assay and the performance of 35-day-old weaned piglets that were treated with the same Lactobacillus isolates, suggesting that C. elegans can be used as a laboratory animal model for preselecting probiotics for control of Salmonella infections.  相似文献   
28.
The potential of using actin bundles for the transport of liposomes and single cells across myosin-coated surfaces is investigated. Compared to that observed with filamentous actin, the liposome transport using actin bundles was more linear in nature and able to occur over longer distances. Bundles, but not filamentous actin, were capable of moving single cells. Cargo unloading from bundles was achieved by incubation with Triton X-100. These data suggest that actin bundling may improve the ability of the myosin motor system for nanotransport applications.  相似文献   
29.
To evaluate compliance with current World Health Organization (WHO) guidelines for postexposure treatment (PET) of rabies, we interviewed all animal bite victims seeking treatment on the same day of each week from 28 December 1994 through 18 January 1995 at the Civil Hospital of Karachi (Pakistan), a major referral center. Of the 143 patients studied, 109 (76%) sustained bleeding transdermal bites (WHO category III). Overall, wounds were not washed with soap or an antiseptic in 69% of victims. All victims received 5% sheep brain-derived vaccine, and only three of the 109 victims with category III bites received rabies immune globulin. PET of rabies in Karachi was deficient by all WHO standards. Although there is a great urgency to improve PET, it will remain a costly and inefficient method of controlling rabies. Reduction of rabies reservoirs is required to decrease human deaths due to rabies in Pakistan and other developing countries in which canine rabies is endemic.  相似文献   
30.
The results of different investigators show that lack of p105 expression is relatively common in human myeloid leukemias, especially in monocytic leukemias. This suggests that loss of p105 expression could contribute to the altered growth control of these cells. So far no clear data exist which show that low p105 levels in AML blasts predict a poor therapy outcome. Therefore it is not very likely that p105 expression will become a strong prognostic factor for the different treatment strategies in AML.  相似文献   
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