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A well-edited assessment can enhance student’s learning motives. Applicability of items, which includes item content and template, plays a crucial role in authoring a good assessment. Templates in discussion contain not only conventional true & false, multiple choice, completion item and short answer but also of those interactive ones. Methods provided for answering interactive question can be click and select, drag and drop, collide, and magnetize, while operational interactive templates can include Link, Match, Classification, and Order.  相似文献   
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Tuberculosis is a continuous threat for health in all parts of the world. In industrialized centers an emerging increase of tuberculosis is observed due to low health standards, poor health education and control, increasing migration and the HIV epidemic. This should alert the pediatrician, since most tuberculosis infections in childhood start with contacts of infected adults with children. There is still a good response to most drugs against tuberculosis, but in some parts of the world the resistance to conventional treatment is an emerging problem. In general incidence, morbidity and mortality of tbc in children of the western world is low and has good prognosis. However, the diagnostic principles and the education of pediatricians for recognizing tbc is still of utmost importance.  相似文献   
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Although similar to firms in other industries that strive to increase their operational efficiency by implementing IT/IS, hospitals face difficulties in obtaining the corresponding benefits of investing in IT/IS. This study investigates the relations among IT/IS performance, IT maturity, IT/IS assessment, IT/IS resource allocation, and user satisfaction in hospitals. IT/IS performance in hospitals is evaluated using a designed questionnaire, along with a case study undertaken to discuss IT/IS assessment and the effect of IT/IS on hospital procedures. The analysis results indicate that hospitals have a higher IT maturity, stronger intention to implement IT/IS assessment, and better IT/IS resource allocation capabilities than firms in other industries. Moreover, both IT/IS assessment and user satisfaction affect IT/IS performance in hospitals.  相似文献   
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Today’s Internet is prominently used for content distribution. Various platforms such as content delivery networks (CDNs) have become an integral part of the digital content ecosystem. Most recently, the information-centric networking (ICN) paradigm proposes the adoption of native content naming for secure and efficient content delivery. This further enhances the flexibility of content access where a content request can be served by any source within the Internet. In this paper, we propose and evaluate a multi-criteria decision algorithm for efficient content delivery applicable for content networks in general (among others, CDN and ICN). Our algorithm computes the best available source and path for serving content requests taking into account information about content transfer requirements, location of the consumer, location of available content servers, content server load and content delivery paths between content servers and consumer. The proposed algorithm exploits two closely related processes. The first level discovers multiple content delivery paths and gathers their respective transfer characteristics. This discovery process is based on long-term network measurements and performed offline. The second process is invoked for each content request to find the best combined content server and delivery path. The cooperation between both levels allows our algorithm to increase the number of satisfied content requests thanks to efficient utilisation of network and server resources. The proposed decision algorithm was evaluated by simulation using Internet scale network model. The results confirm the effectiveness gain of content network architectures that introduce network awareness. Moreover, the simulation process allows for a comparison between different routing algorithms and, especially, between single and multipath routing algorithms.  相似文献   
6.
Software testing during the development process of embedded software is not only complex, but also the heart of quality control. Multi-core embedded software testing faces even more challenges. Major issues include: (1) how demanding efforts and repetitive tedious actions can be reduced; (2) how resource restraints of embedded system platform such as temporal and memory capacity can be tackled; (3) how embedded software parallelism degree can be controlled to empower multi-core CPU computing capacity; (4) how analysis is exercised to ensure sufficient coverage test of embedded software; (5) how to do data synchronization to address issues such as race conditions in the interrupt driven multi-core embedded system; (6) high level reliability testing to ensure customer satisfaction. To address these issues, this study develops an automatic testing environment for multi-core embedded software (ATEMES). Based on the automatic mechanism, the system can parse source code, instrument source code, generate testing programs for test case and test driver, support generating primitive, structure and object types of test input data, multi-round cross-testing, and visualize testing results. To both reduce test engineer's burden and enhance his efficiency when embedded software testing is in process, this system developed automatic testing functions including unit testing, coverage testing, multi-core performance monitoring. Moreover, ATEMES can perform automatic multi-round cross-testing benchmark testing on multi-core embedded platform for parallel programs adopting Intel TBB library to recommend optimized parallel parameters such as pipeline tokens. Using ATEMES on the ARM11 multi-core platform to conduct testing experiments, the results show that our constructed testing environment is effective, and can reduce burdens of test engineer, and can enhance efficiency of testing task.  相似文献   
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The metabolizable energy intake (MEI) required for maintenance and the efficiency of utilization of metabolizable energy available for gain (MEA) were determined for a line of mice (rapid growth) selected for 41 generations for rapid postweaning weight gain and for a contemporarily mated line (control) that had been randomly selected. Feed intake of individually housed rapid growth and control males was restricted above maintenance or was ad libitum from 21 to 42 days of age. Regressions of change in body energy per unity metabolic body size on MEI per unit metablic body size showed that the maintenance requirement for each line of mice was 176 kcal per unit metabolic body size per day and that the rapid growth line was more efficient than the control line in utilizing MEA (50% vs. 23%) to promote an increase in body energy. Although the proportions of MEA used for fat (PF) and lean (PL) gains and the net efficiencies with which those proportions were utilized for fat (NF) and lean (NL) gains were unknown, the products of proportion and efficiency for fat gain (PF X NF or fat energy deposition coefficient) and for lean gain (PL X NL or lean energy deposition coefficient) were determined. The results demonstrate that 41 generations of selection for rapid postweaning weight gain did not change the lean energy deposition coefficient, but did alter the fat energy deposition coefficient. These data suggest that the two lines of mice use different proportions of MEA for fat gain and/or utilize MEA for fat gain at different efficiencies.  相似文献   
8.
We have previously shown that hypoxia causes the activation of nuclear factor-kappa B (NF-kappa B), and the phosphorylation of its inhibitory subunit, I kappa B alpha, on tyrosine residues. With the use of dominant negative mutants of Ha-Ras and Raf-1, we investigated some of the early signaling events leading to the activation of NF-kappa B by hypoxia. Both dominant negative alleles of Ha-Ras and Raf-1 inhibited NF-kappa B induction by hypoxia, suggesting that the hypoxia-induced pathway of NF-kappa B induction is dependent on Ras and Raf-1 kinase activity. Furthermore, although conditions of low oxygen can also activate mitogen-activated protein kinases (ERK1 and ERK2), these kinases do not appear to be involved in regulating NF-kappa B by low oxygen conditions, as dominant negative mutants of mitogen-activated protein kinase do not inhibit NF-kappa B activation by hypoxia. Since Ras and Raf-1 have been previously shown to work downstream from membrane-associated tyrosine kinases such as Src, we determined if the Src membrane-associated kinase was also activated by low oxygen conditions. We detected an increase in Src proto-oncogene activity within 15-30 min of cellular exposure to hypoxia. We postulate that Src activation by hypoxia may be one of the earliest events that precedes Ras activation in the signaling cascade which ultimately leads to the phosphorylation and dissociation of the inhibitory subunit of NF-kappa B, I kappa B alpha.  相似文献   
9.
The selection of a best sequential shots for a given start cue position is a major challenging task in a billiard game. A new algorithm is proposed as a strategy to apply maximum tolerance angle search sequentially. The strategy considers combinations among all pockets and target object balls during both the pre and post collision shots selection processes. A simulation program is developed to test the strategy in a competition scenario by players with different proficiencies. The level of proficiency of players in the competition is controlled by a threshold value as a criterion to evaluate capability to conduct consecutive shots and when to give out right of play. The winning score of each game (win rate) is used as a performance comparison index among different gaming situations and to verify the effectiveness of the algorithm. The initial results of several simulation games using our strategy show that higher proficiency player can out beat lower proficiency player easily. This is consistent with the gaming situation in the real world, showing the consistency of our simulation program. The simulation also verifies that the play order does decide the final competition outcomes, when the players?? proficiencies are close to each other. This work is the first to investigate the effects of consecutive shots and order of play on the billiard gaming results. A low cost training system is proposed to verify the efficiency of the repositioning algorithm in real world settings. The system adapts an augmented reality technology to instruct users for reliable aiming assistance. It makes use of a vision system for cue ball, object ball locations and cue stick velocity tracking. In all, the simulation program can provide an initial proof of the effectiveness of the reposition algorithm in the competition situation. Experiments results of maximum tolerance angle all pocket search strategy using our training facility as tested by users with different skill levels all out performed the results without guidance for the set of users with the same proficiency.  相似文献   
10.
The human placenta at term produces large quantities of corticotropin releasing hormone (CRH) and prostanoids. These hormones play an important role in the maintenance of pregnancy, and the initiation and progress of labor; yet little is known of factors affecting their regulation and the interrelationship of CRH and prostanoid production. In these studies we have investigated the effect of dexamethasone on the production of CRH and prostanoids from fresh human term placental tissues. The basal release of prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2 alpha), thromboxane B2 (TxB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) from human term placental explants increased from the fifth hour in culture, while the release of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) was not significantly changed during this period. The addition of dexamethasone (10(-8) M) to the perifusing medium resulted in a rapid and dramatic inhibition of PGE2, PGF2 alpha, PGFM, TxB2 and 6-keto-PGF1 alpha release. On the other hand, CRH release was not significantly changed throughout the seven hours of incubation with dexamethasone. These data demonstrate that glucocorticoids at physiologic concentrations can inhibit human term placental prostanoid production, and thus glucocorticoid production may play an important role in the physiological regulation of placental prostanoid production in the human placenta. However, dexamethasone did not alter CRH release, demonstrating that the inhibition of placental prostanoids by dexamethasone is not a CRH mediated event.  相似文献   
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