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91.
Object segmentation and labeling by learning from examples   总被引:1,自引:0,他引:1  
We propose a system that employs low-level image segmentation followed by color and two-dimensional (2-D) shape matching to automatically group those low-level segments into objects based on their similarity to a set of example object templates presented by the user. A hierarchical content tree data structure is used for each database image to store matching combinations of low-level regions as objects. The system automatically initializes the content tree with only "elementary nodes" representing homogeneous low-level regions. The "learning" phase refers to labeling of combinations of low-level regions that have resulted in successful color and/or 2-D shape matches with the example template(s). These combinations are labeled as "object nodes" in the hierarchical content tree. Once learning is performed, the speed of second-time retrieval of learned objects in the database increases significantly. The learning step can be performed off-line provided that example objects are given in the form of user interest profiles. Experimental results are presented to demonstrate the effectiveness of the proposed system with hierarchical content tree representation and learning by color and 2-D shape matching on collections of car and face images.  相似文献   
92.
陈旭  唐莉君 《现代电子技术》2006,29(23):119-120
随着各高校校园网络规模的不断扩大和各种应用的急剧增加,各种新的网络问题也在不断出现。Sniffer是网络管理员进行网络管理的有效工具,可以有效地对网络进行实时监控,及时发现网络中存在的各种问题。本文首先介绍了Sniffer的工作原理,其次给出了实现Sniffer功能的编程流程图,并用C语言给出了编程所需的关键代码。  相似文献   
93.
数值试井在白6-2井测试资料分析评价中的应用   总被引:1,自引:0,他引:1  
数值试井是在近来发展的一项新的试井解释技术,具有处理非均质,复杂边界油气藏问题的优点,弥补了常规解析试井技术的不足。运用数值试井解释技术,结合动、静态资料,通过对白6-1断块白6-2井测试资料的综合分析评价,确定了储层渗流参数,落实了该气藏的边界情况,为该断块下一步开发提供可靠依据。  相似文献   
94.
皖北地区夏季高温多雨,冬季严寒,气候较为恶劣,在该地区宜推广应用SMA混合料铺筑表面层。在进行SMA配合比设计时,必须严格控制原材料的质量,经过精心设计、精心施工,才能修建出一条成功的SMA路面。  相似文献   
95.
SCB火工品的研究与发展   总被引:9,自引:2,他引:7  
文章评述了半导体桥火工品问世以来的研究成果与发展趋势。主要内容有半导体桥作用机理、半导体桥的结构与封装、半导体桥火工品的特点、半导体桥火工品的应用、半导体桥火工品的研究和发展趋势。  相似文献   
96.
固液分离水力旋流除砂器的数值模拟   总被引:3,自引:0,他引:3  
利用CFD软件,采用雷诺应力模型分别计算了300型和250型水力旋流除砂器的内流场,得到了2种水力旋流除砂器的轴向、径向、切向速度及压强的分布曲线。通过对所得结果的分析,发现模拟结果基本符合旋流除砂器的运行规律。比较2种旋流除砂器的内流场,表明改进的300型水力旋流除砂器的结构及分离能力优于原来250型水力旋流除砂器,为水力旋流除砂器的优化设计和选型提供了可靠的设计依据。  相似文献   
97.
对丙烯醛水合、加氢制1,3-丙二醇工艺进行了中试研究,主要对小试技术的可靠性进行验证。结果表明,丙烯醛经水合、加氢制1,3-丙二醇的工艺技术可行,反应器、精馏塔等设备设计合理。中试丙烯醛水合单程转化率为45%~55%,3-羟基丙醛选择性达到了93%左右,3-羟基丙醛加氢收率接近100%,产品1,3-丙二醇的醛基质量分数降至5μg/g以下。与小试结果相比较,中试的水合选择性明显提高,加氢催化剂活性寿命延长。  相似文献   
98.
The users' interest can be mined from the web cache and can be used widely. The interest can be specialized by the two-tuple (term, weight) in the simple interest model, in which the association relations are not mined, and then the interest cannot be associated in expressing the users' interest. Based on analyzing the WWW cache model, this letter brings forward a two-dimensional interest model and gives the interrelated methods on how to store the two-dimensional interest model effectively.  相似文献   
99.
The kinetics of substrate removal by the liver and the resulting nonlinear changes in unbound fraction along the flow path at varying input drug concentrations were examined by a model simulation study. Specifically, we varied the binding association constant, KA, and the Michaelis-Menten constants (Km and Vmax) to examine the steady state drug removal (expressed as hepatic extraction ratio E) and changes in drug binding for (i) unienzyme systems and (ii) simple, parallel metabolic pathways; zonal metabolic heterogeneity was also added as a variable. At low KA, E declined with increasing input drug concentration, due primarily to saturation of enzymes; only small differences in binding were present across the liver. At high KA, a parabolic profile for E with concentration was observed; changes in unbound fraction between the inlet and the outlet of the liver followed in parallel fashion. Protein binding was the rate-determining step at low input drug concentrations, whereas enzyme saturation was the rate-controlling factor at high input drug concentration. Heterogeneous enzymic distribution modulated changes in unbound fraction within the liver and at the outlet. Despite marked changes in unbound fraction occurring within the liver for different enzymic distributions, the overall transhepatic differences were relatively small. We then investigated the logarithmic average unbound concentration and the length averaged concentration as estimates of substrate concentration in liver in the presence of nonlinear drug binding. Fitting of simulated data, with and without assigned random error (10%), to the Michaelis-Menten equation was performed; fitting was repeated for simulated data obtained with presence of a specific inhibitor of the high-affinity, anteriorly distributed pathway. Results were similar for both concentration terms: accurate estimates were obtained for anterior, high affinity pathways; an overestimation of parameters was observed for the lower affinity posteriorly distributed pathways. Improved estimations were found for posteriorly distributed pathways upon inhibition with specific inhibitors; with added random error, however, the improvement was much decreased. We applied the method for fitting of several sets of metabolic data obtained from rat liver perfusion studies performed with salicylamide (SAM) (i) without and (ii) with the presence of 2,6-dichloro-4-nitrophenol (DCNP), a SAM sulfation inhibitor. The fitted results showed that SAM sulfation was a high-affinity high-capacity pathway; SAM glucuronidation was of lower affinity but comparable capacity as the sulfation pathway, whereas SAM hydroxylation was of lower affinity and lower capacity.  相似文献   
100.
One month following the Great Hanshin Earthquake of January 17, 1995, we conducted a survey of 173 hospitals in Aichi Prefecture to pinpoint problems related to their actual disaster-readiness and the medical backup systems in place to deal with such disasters. This study revealed that staff at 50% of the surveyed hospitals could reach the hospital within an hour, but that communication is almost entirely dependent on phone lines, suggesting that cordless/portable/mobile phones, radio systems, Internet, communications satellites and the like should be studied in the days to come for possible use as effective communication alternatives in times of disaster. Whereas 92% of the surveyed hospitals had manuals dealing with fire outbreaks, other areas were less well represented. For example, only 36.9% of surveyed hospitals had manuals for earthquakes, 31.7% had manuals for power outages and 14.2% had manuals to deal with flooding and water disasters. New manuals must be developed incorporating the key points garnered from experience (especially Hanshin) and be ready for use immediately. It is the time for each hospital to seriously rethink the measures it should take to deal with disasters.  相似文献   
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