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51.
PAN Bin ZHONG Fan WANG Shuai CHEN Wei & PENG QunSheng The State Key Lab of CAD & CG Hangzhou China 《中国科学:信息科学(英文版)》2011,(6):1199-1206
Salient structural elements are ubiquitous in natural textures, and their distribution exhibits some stochastic distribution features. Current texture synthesis algorithms can neither preserve the integrity of the elements nor capture this distributive information. We present an algorithm to treat this high-level visual information. Here, we address the issue by taking specific care of the structural elements. Our texture synthesis process grows the target texture one structural element at a time. A Markov ... 相似文献
52.
Obtaining good visual quality and high hiding capacity with reversible data hiding systems is a technically challenging problem. In this paper, we propose a simple reversible data hiding scheme that uses a complementary hiding strategy. The proposed method embeds one secret bit horizontally and vertically into one cover pixel of a grayscale cover image by decreasing odd-valued pixels and increasing even-valued pixels by one. Experimental results show that the hiding capacity measured by bit per pixel (bpp) of the proposed scheme is at least 1.21 bpp with a PSNR (peak signal-to-noise ratio) value greater than 52 dB for all standard test images. Especially in the case of four-layer embedding, the PSNR value of the proposed method is still greater than 51 dB at a hiding capacity of about 5 bpp for all standard test images. In addition, the proposed method is quite simple because it primarily uses additions and subtractions. These results indicate that the proposed scheme is superior to many existing reversible data hiding schemes introduced in the literature. 相似文献
53.
本文针对J2EE技术进行深入研究,对Struts框架进行深入剖析,研究Struts框架的内部结构、运作流程,以及对MVC设计模式的分析研究和对MYSQL数据库进行深入了解,并提出了一个以J2EE为平台,使用Struts框架,引入MVC设计模式的基于J2EE的新闻发布系统。本系统提高了用户获取新闻信息的及时性,使用户能更... 相似文献
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基于MATLAB的小波包信号消噪处理 总被引:2,自引:0,他引:2
信噪分离是小波包应用于信号分析的一个重要方面。本文在基于MATLAB的基础上,采用小波包对含高斯白噪声信号进行分解,通过不同的量化阈值对小波包系数进行处理、重构得出小波包消噪后的信号。计算机仿真结果表明,用不同量化阈值的小波包可对含高斯白声信号进行消噪重构。 相似文献
56.
随着中国移动通信网覆盖范围的不断扩大,在该网络支持下的电子应用系统也得到广泛使用,本文就在移动网覆盖范围内的防盗告警监控系统的设计加以详细说明,介绍了无线手机模块的工作原理及在该系统中使用方法。另外就户外监控中的馈电方式及太阳能电池在本设计中的重要应用做了说明。无线告警监控系统运行不受时间地点的限制,可以在无供电的环境中长期使用。 相似文献
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BACKGROUND: A durable power of attorney for health care (DPA) allows a person to appoint a surrogate decision-maker for any future period of mental incapacity. The absence of advance directives can lead to confusion and the expenditure of resources while trying to exert a substituted judgment. METHODS: The Wisconsin DPA was presented with an organized pilot program to 150 residents who had been judged by their social workers to have the capacity to make informed decisions regarding medical care. The reasons residents gave for accepting or rejecting a DPA were analyzed. RESULTS: Seventy-nine percent prepared a DPA. Reasons for signing included allowing the resident to decide who would make medical decisions and assuring that specific wishes would be carried out. Twenty-one percent did not execute a DPA. Reasons were categorized as confusion and misunderstanding regarding the legal system, mistrust, or social isolation. CONCLUSIONS: The high rate (79%) of DPA completion is probably related to individually counseling residents. However, competent residents who despite counseling do not choose to execute a DPA can have detailed advance directives ("living wills") prepared without appointing a decision-maker. 相似文献
59.
The frequent difficulties encountered in the diagnosis of pediatric sarcomas, caused by the lack of observable differentiation at the light microscopic level, has led to the routine use of immunohistochemistry in pediatric surgical pathology. To a large degree the advent of this staining technique has led to the correct assessment of many perplexing lesions that previously would have been given inconclusive diagnoses. However, with increased usage and testing, it has become apparent that there are few, if any, "magic bullets" in immunohistochemistry for pediatric pathologists. Thus, it behooves diagnosticians to be careful in the usage of this technique, to be aware of possible discrepancies in its results, and to remember the ancillary nature of its application. The following article will review selected markers commonly used in pediatric surgical pathology, from both previous reports and the author's perspective, and will briefly consider several new phenotypic markers which have potential utility with childhood sarcomas. 相似文献
60.
R Jedeikin SK Makela AT Shennan RD Rowe G Ellis 《Canadian Metallurgical Quarterly》1982,28(2):317-322
Isoenzymes of creatine kinase (ATP:creatine phosphotransferase; EC 2.7.3.2; CK) were measured by electrophoresis in serum from cord blood and skin-puncture blood taken from 45 healthy full-term infants during the first three postnatal days. Mean total CK activities (in U/L at 30 degrees C) were 185 in cord samples, 536 in samples taken between 5--8 h postnatally, 494 between 24--33 h, and 288 in the 72-100 h samples. Values for all three isoenzymes increased to a peak over this period, with the highest values generally being found in the samples taken 5--33 h after birth; the subsequent decline was most rapid for CK-BB. Serum CK isoenzymes in cord samples and those taken at 72--100 h in the 11 babies delivered by cesarian section did not differ significantly from those of babies delivered vaginally. However the postnatal increases in total CK, CK-MM, and CK-MB (but not in CK-BB) were significantly greater in those patients born by vaginal delivery. The reasons for the increases in CK isoenzymes after birth are not clear, but our results and reported studies on the ontogeny of CK suggest that CK-MB cannot be regarded as a "cardiac-specific" isoenzyme in the neonatal period. 相似文献