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1.
By leveraging the secret data coding using the remainder storage based exploiting modification direction (RSBEMD), and the pixel change operation recording based on multi-segment left and right histogram shifting, a novel reversible data hiding (RHD) scheme is proposed in this paper. The secret data are first encoded by some specific pixel change operations to the pixels in groups. After that, multi-segment left and right histogram shifting based on threshold manipulation is implemented for recording the pixel change operations. Furthermore, a multiple embedding policy based on chess board prediction (CBP) and threshold manipulation is put forward, and the threshold can be adjusted to achieve adaptive data hiding. Experimental results and analysis show that it is reversible and can achieve good performance in capacity and imperceptibility compared with the existing methods. 相似文献
2.
In this paper, we proposed a novel adjustable data hiding method. Our proposed method, which is based on exploiting modification direction (EMD) method, is called the “multi-group exploiting modification direction” method. In the multi-group method, we combine several pixel-groups to embed secret data according to the constructed switch map to simply avoid the conversion redundancy of the EMD method and the spatial redundancy of the section-wise strategy, as well as to efficiently increase the probability of achieving larger embedding capacity. According to the experimental results and mathematical justification, we verified that the multi-group method can achieve higher embedding payload and better visual quality of the image than the EMD method and section-wise strategy for simulated and real secret data. 相似文献
3.
M. C. Nataraja T. S. Nagaraj S. Bhavanishankar B. M. Ramalinga Reddy 《Materials and Structures》2007,40(6):543-552
This paper presents an experimental investigation to advance a stepwise procedure to proportion plain and slag concrete mixes
with burnt coal cinder waste as coarse aggregate. When typical strength of coarse aggregate in concrete is lower than the
concrete strength required, conventional methods such as British Method, ACI and country’s standard code cannot be used directly
since failure of concrete is predominantly by aggregate crushing. To analyze the data, concrete, for simplicity, is regarded
as two phase composite of cement mortar matrix and coarse aggregate. With the concrete and constituent cement mortar matrix
strengths and their respective volume fractions as input parameters, the typical strength of coarse aggregate in concrete
is determined from linear law of mixtures. Using again the same law, the cement mortar matrix strength required for higher
or at par to that of the typical aggregate strength is calculated. To arrive at water–cement ratio for matrix strength, the
Generalized Abrams’ law is employed. 相似文献
4.
带凝析气顶油藏气顶油环协同开发技术政策研究 总被引:1,自引:0,他引:1
让纳若尔油田A南油藏带较大凝析气顶,主要依靠气顶膨胀能量开采油环,针对目前油井气窜,油气资源损失严重等问题,考虑合理开采气顶,并实现油气协同开发,运用油藏数值模拟方法进行了相关的开发技术政策研究。结果表明:气顶最佳的投产时机为2013年,合理的采气速度为4%~5%。将油藏的日注入总量定在约3750 m3/d,屏障注水比例和面积注水比例为8:2时,既保证了气顶气和凝析油的合理开采,还能充分利用气顶能量(屏障注水井的外围气顶气)驱油,同时最大限度提高注入水利用率。 相似文献
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含煤岩系中赋存有可供利用的油页岩、煤层气、碳沥青、石煤、石油等资源,这些能源矿产与煤有成因关系,往往伴生或共生。本文综合分析了近年来油页岩、煤层气、碳沥青和石煤的开发利用现状,并指出我国应大力发展与煤伴生(共生)可燃有机矿产的开发利用,走可持续发展的道路。 相似文献
7.
基于Web的澳门旅游导引系统的设计与实现 总被引:3,自引:0,他引:3
主要论述了基于Web的澳门旅游信息系统的设计开发方案及具体实现步骤。该系统应用目前广为流行的基于Web的数据库动态开发技术,建设成为Browser/Server模式的多用户分布式信息系统。同时为了实现系统的智能化处理,构建了旅游相关推荐专家系统。 相似文献
8.
采用Visual Basic6.0作为开发工具,以墙下钢筋混凝土条形基础为例,介绍了建筑工程结构设计中计算程序的编制方法和原理。利用这类小程序来解决工程设计中的计算问题,不仅程序界面美观,数据输入简捷,而且计算速度快,结果准确,也节省了大量时间。 相似文献
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通过分析福建省连城锰矿兰桥矿区的地质和开采现状与历史,探讨了连城锰矿兰桥矿区通过技术改进、设备更新,提高资源利用率,采用边采边探、探采结合的开采方法增加矿石储量,以及延长矿山服务年限的技术措施。 相似文献
10.
卢宝华 《辽阳石油化工高等专科学校学报》2001,17(3):47-50
阐述了在应用开发工具PowerBuilde进行系统开发过程中遇到的开发效率问题和解决方法。 相似文献