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1.
基于样本块的纹理合成修复算法(Criminisi算法)在匹配样本块时,因为使用全局搜索策略而降低了有效匹配效率。针对这一问题,重点研究了一种改进的基于样本块的数字图像修复算法。改进算法考虑到相邻像素块的相似性,对图像样本区域进行了重构,减少了样本块搜索范围,提高了图像修复效率。  相似文献   

2.
李捷 《科技广场》2008,(1):22-24
布局问题来源于生产实际,在提高板材利用率以节约原材料,降低成本,提高经济效益,对各行业均有重要意义。针对遗传算法在矩形件布局问题中的实际特点,并分析了矩形件布局给定排放顺序的排放算法,并提出了一种新的排放算法——最低水平线旋转搜索法,并将这种算法和遗传算法结合应用于矩形件布局问题的求解。计算实例表明这种新的排放算法可以和遗传蚁群算法有效的结合。  相似文献   

3.
针对传统遗传算法的早熟收敛问题,在著名的"基因块"假设的基础上,提出了一种改进算法:利用设计的新算子对传统遗传算法演化过程中被淘汰的个体进行二次演化,使得可能包含在将来的演化中对结果的全局最优性产生重要影响的基因块得以保留,以此来避免遗传算法早熟收敛现象。实验结果证明了该改进算法可以有效地避免早熟收敛,提高了算法全局优化能力。  相似文献   

4.
有效的链路层的复激活算法可以提高语义系统的检错性能。传统方法采用自适应模式匹配方法实现语义系统的跨层链路复激活,当检错码冗余数据块随机放置时,不能有效实现语义检错。提出一种基于检错码静默补偿的跨层链路复激活算法,构建语义系统网络控制模型,设计检错码编码数据块放置方法,提出检错码静默补偿机制并实现跨层链路复激活算法改进。实验结果表明,采用该算法能有效实现语义系统检错码跨层链路激活,谱峰复激活搜索明显,任务执行精度提高17%,算法在语义网通信编码设计等领域具有较好的应用价值。  相似文献   

5.
针对大规模地形存在的数据量多、渲染速度慢等问题,提出了一种高效的地形场景优化方法。对GeoMipMaps算法进行改进,利用地形分块技术进行视域剔除,减少地形块数量;同时,引入高度判断方法,保留地形块高度数据,在降低需要绘制三角形数量的同时保留较多的地形起伏细节。实验结果表明,该方法能有效提高地形漫游的效率和可视化结果,实时生成大规模地形。  相似文献   

6.
《内江科技》2016,(12):50-51
设计算法求解约束优化问题是一个热点问题。本文针对传统教学优化算法的教学因子进行了改进,提出了改进的教学优化算法,对效果用一个复杂的数值例子进了验证,并与标准的教学优化算法进行比较,结果得到了有效的改进。  相似文献   

7.
针对关联规则挖掘算法中存在事务之间的某种关联性的数据无法区分的问题,本文将蚁群算法和加权概念引入到挖掘算法中,首先分析了目前加权关联规则挖掘算法的不足,提出了将蚁群算法引入到加权关联规则中,并对蚁群算法中的应度函数,状态转移规则和信息素更新的改进,并采用矩形向量作为事务存储结构进行连接和剪枝。仿真实验中与基本Apriori算法进行比较,并通过将本校的课程资源作为挖掘对象,结果说明本文算法具有良好的挖掘效果。  相似文献   

8.
针对单一的特征提取算法在运动员检测中还存在漏检较多的问题,本文提出了一种中层特征块分类的运动视频运动员检测模型。首先采用中层特征块作为描述运动员的特征,然后采用SLIC算法进行超像素分割,利用像素的CIELAB颜色空间和XY空间坐标构建像素的5维特征,最后采用高斯分量的全协方差混合高斯模型建立前景背景像素描述模型,提高检测精度。仿真实验结果表明,本文提出的改进模型,相比较HOG算法和SVM算法,检测结果更准确的表示了运动员区域。  相似文献   

9.
蚁群算法是一种新型的启发式算法,它具有许多优良性质,被广泛用于求解组合优化问题,但基本蚁群算法也存在诸多不足。为使蚊群算法对应TSP问题的解更加优良,提出了一种改进的蚁群算法并对它进行了试验,结果表明改进算法是有效的,这也为蚁群算法的优化提供了一个新的途径。  相似文献   

10.
针对高斯混合模型算法(GMM)对初始参数敏感、易陷入局部最优的问题,提出一种基于改进海洋捕食者算法优化的GMM算法(MMPA-GMM)。首先基于混沌序列和伪对立学习策略初始化种群,引入非线性收敛因子平衡MPA算法的全局与局部搜索,同时提出融入社会等级制度的位置更新策略;然后从搜索能力和收敛速度对改进的MPA进行分析;最后以S_Dbw指标作为算法的适应度函数,利用改进的MPA优化GMM算法的初始参数。实验结果表明,改进的MPA在4种测试函数上表现良好,并且MMPA-GMM算法对4个数据集的聚类效果均有改善,有效避免了GMM算法陷入局部最优的问题。  相似文献   

11.
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.  相似文献   

12.
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.  相似文献   

13.
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.  相似文献   

14.
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.  相似文献   

15.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.  相似文献   

16.
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.  相似文献   

17.
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.  相似文献   

18.
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.  相似文献   

19.
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.  相似文献   

20.
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence  相似文献   

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