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This paper proposes a robust zero-watermarking algorithm based on Complex Zernike moment to resist various signal processing operations and geometric transformations. Zero watermarking algorithm changes the operation method of embedding watermark in the original data. Instead, it employs the significant characteristics of the original data to construct watermarking information to successfully avoid the contradiction between robustness and invisibility and increase the robustness of the watermarking. First, perform displacement and scaling standardization process for the tested image, then calculate the Complex Zernike Moment argument of the standardized image to get an argument value; after binarization of the argument value, construct the feature image regarded as watermarking. Experimental results show that the proposed method has strong robustness to various attacks specially geometric attacks.

The Multi-lateral Wells Technology applied in myriad applications worldwide and provides intelligent solutions of many challenges faces the industry, But it doesn't applied in Sudanese fields yet. By study of Block 15 Sudanese offshore field conditions we can find that multi-lateral technology is useful technology which achieves many advantages by reduce the cost in both exploration and development stages of the field life. In this paper the authors providing a proposed design of Multi-lateral Wells Technology application to re-enter Tokar-1 well which located in Red Sea offshore Sudan region in Block 15 authorization area of Red Sea Petroleum Operating Company (RSPOC). The Design of Tokar-1 multi-lateral application made depends on several considerations about the targets of this application and the geological background of the area of study. The Directional Wellpaths planning of this application planned using Landmark Compass® Software. And after completing the design of the application drilling and completion techniques manually the authors devised guidance software to help the multi-lateral designer to select his optimum option among multi-lateral wells drilling and completion techniques depend on his field conditions, and made analysis of the manual design of Tokar-1 Multi-lateral well using this software and made a comparison between the results.

Reversible watermarking has drawn a lot of interest in recent years. Sachnev et al proposed reversible watermarking algorithm by combining prediction technology, histogram shifting technology and sorting technology, which has good performance. However, their method is against the characteristics of the human visual system. In this paper, we propose a reversible watermarking algorithm to improve Sachnev et al algorithm by using new sorting method. The performance of the proposed reversible watermarking algorithm is evaluated and compared with Sachnev et al method and other methods. The results indicate that the proposed algorithmhas good performance than Sachnev et al method and can embed data with less distortion.Keywords: Prediction error; Reversible watermarking; Sorting. INTRODUCTIONIn some certain applications areas, such as military, medicine and law, requirements of the integrity of the original carrier are relatively high, even distortion brought by the watermarking is not allowed, which requires lossless embedding watermark information. Reversible watermarking is also called lossless watermark, the non-distortion watermark and the erasable watermark; it can restore the original carrier without distortion after the watermarking information is extracted. (Tian, 2003) proposed the Difference Expansion Method when the research of reversible watermarking with large capacity began. The image is divided into pairs of pixels, then the differences and average values are calculated, then the binary form is expanded and the watermark is embedded right after most significant bit. One bit can be embedded in every pixels pair.(Kamstra and Heijmans, 2005) enhanced Tian's method. They sorted pairs according correlation between adjacent pixels, thus reduced location map and improved embedding capacity. (Thodi and Rodriguez, 2007)introduced expansion of prediction error plan, they replaced the difference between the adjacent pixels by a pixel prediction, Later they combined the histogram shift algorithm with prediction technology. (Tai et al., 2009) introduced a reversible method based on histogram modification. They used distribution of pixel differences to achieve large hiding capacity and low distortion. (Tsai et al., 2013)presented a reversible algorithm for grayscale images based on the histogram modification technique. A histogram is constructed from the differences between each pixel and its neighbors. They used a modified histogram shifting algorithm to embed a secret message into the pixels. This algorithm can achieve higher embedding capacity and imperceptible distortion. (Sachnev et al., 2009) combined prediction

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