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71.
72.
本文对广钢创建学习型企业和搞好职工培训工作的问题进行了探讨,提出了在创建学习型企业过程中,加强和改进职工培训工作的思路和办法。  相似文献   
73.
This paper proposes an optimized content-aware authentication scheme for JPEG-2000 streams over lossy networks, where a received packet is consumed only when it is both decodable and authenticated. In a JPEG-2000 codestream, some packets are more important than others in terms of coding dependency and image quality. This naturally motivates allocating more redundant authentication information for the more important packets in order to maximize their probability of authentication and thereby minimize the distortion at the receiver. Towards this goal, with the awareness of its corresponding image content, we formulate an optimization framework to compute an authentication graph to maximize the expected media quality at the receiver, given specific authentication overhead and knowledge of network loss rate. System analysis and experimental results demonstrate that the proposed scheme achieves our design goal in that the rate-distortion (R-D) curve of the authenticated image is very close to the R-D curve when no authentication is required  相似文献   
74.
Domain-Driven, Actionable Knowledge Discovery   总被引:1,自引:0,他引:1  
Data mining increasingly faces complex challenges in the real-life world of business problems and needs. The gap between business expectations and R&D results in this area involves key aspects of the field, such as methodologies, targeted problems, pattern interestingness, and infrastructure support. Both researchers and practitioners are realizing the importance of domain knowledge to close this gap and develop actionable knowledge for real user needs.  相似文献   
75.
Itwasreported[1] thatthemicro stereostructureofprimaryausteniteincastironconsistsofprimarystemsandsecondaryarmsthat growaccordingtodendritecrystalsbranchrule ,andsomeofprimaryausteniteevenhavethirdarms .MiyakeHetal[2 ]proposedaconceptofregionmodelbystudying…  相似文献   
76.
多级网络多处理机系统的性能评估   总被引:2,自引:1,他引:1  
本文建立了多级网络(δ-网)多处理机系统的马尔柯夫模型,为系统结构参数和任务粒度的选择提供了依据。文中分析了处理机数目、网络结构参数和任务粒度对系统性能的影响,并对模型计算结果和仿真结果作了比较。  相似文献   
77.
Nucleation of solidification in liquid droplets   总被引:2,自引:0,他引:2  
Analytical and numerical methods have been developed to analyze the solidification kinetics of a mass of liquid droplets dispersed in a fluid or solid matrix using classical nucleation theory. The resulting analytical expressions and numerical calculations can be compared directly with calorimetric measurements of the droplet solidification exotherms to obtain information about the nucleation mechanism. With increasing contact angle at the solid-liquid-matrix triple point, the solidification onset, peak, and end temperatures and exothermic peak height all decrease sharply and the droplet solidification exotherms become broader. Decreasing either the droplet radius or the number of potential catalytic nucleation sites produces a similar but smaller effect. Distributions in droplet radius, contact angle, and nucleation sites have no effect on the solidification peak temperature, but the droplet solidification exotherms become broader and more symmetric. The solidification onset temperature is independent of cooling rate in the calorimeter, but the solidification peak and end temperatures decrease and the exothermic peak height increases with increasing cooling rate. Predicted droplet solidification exotherms are in excellent agreement with detailed experimental measurements on 10-nm-radius Cd droplets embedded in a solid Al matrix. Analytical predictions give best-fit values of 43 deg and 430 for the contact angle and the number of potential catalytic nucleation sites per droplet, respectively; numerical predictions give best-fit values of 43 deg and 750 for the contact angle and the number of potential catalytic nucleation sites per droplet, respectively.  相似文献   
78.
研究了烧成及热处理工艺对钛酸锶铅基热敏材料的阻温特性及显微结构的影响。通过扫描电镜(SEM)和能量分散仪(EDAX)分析了材料的显微结构及不同形貌晶粒的成份。通过对组成、烧成及热处理工艺的控制,可得到具有V型PTCR特性的热敏材料。  相似文献   
79.
To study the role of vagal afferent C-fibers in resiniferatoxin (RTX)-induced bronchoconstriction in vivo, 30 guinea pigs weighing 347 +/- 28 g were evenly and randomly divided into five groups: Group 1, control; 2, chronic vagotomy; 3, local capsaicin (acute); 4, local capsaicin (chronic); and 5, systemic capsaicin. Each animal was anesthetized with pentobarbital sodium, cannulated with a tracheal cannula and venous catheter, paralyzed with gallamine triethiodide, and artificially ventilated. All animals were pretreated with atropine and phenoxybenzamine. Immediately after RTX was intravenously injected, each animal in the control group exhibited profound decreases in maximal expiratory flow, dynamic respiratory compliance, and total lung capacity, as well as an increase in functional residual capacity, indicating severe airway constriction. Animals in Groups 2-4 exhibited partial abolishment, while those in Group 5 showed complete abolishment of the RTX-induced bronchoconstriction. In 12 additional animals (6 animals each in control and chronic vagotomy groups), chronic vagotomy caused also suppressive effects on capsaicin-induced airway constriction. At one min, our data demonstrate that 36-51% of noncholinergic bronchoconstriction is due to the vagal component while the remaining constriction is due to the nonvagal component. Thus, the nonvagal component plays a significant role in this type of tachykinin-mediated airway constriction.  相似文献   
80.
用正电子湮没方法研究了新型超微晶软磁合金的微观结构缺陷,样品选用的是在不同温度下退火的Fe81P12C3Cu1Mo0.5Si2.5合金,结果表明,合金的微观结构构陷大小,密度随退火温度有规律地变化,这种现象可能与非晶的晶化过程有关。  相似文献   
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