Một số phương pháp bảo vệ bản quyền ảnh số và ứng dụng

Một số phương pháp bảo vệ bản quyền ảnh số và ứng dụng
Hoàng, Thị Kim Oanh
Luận văn đề cập tới vấn đề giấu thông tin cho ảnh, một dạng dữ liệu được sử dụng nhiều và cũng hay bị lợi dụng trên internet.
Chi tiết bài viết xin mời tham khảo tại http://repository.vnu.edu.vn/handle/VNU_123/12065
Title: Một số phương pháp bảo vệ bản quyền ảnh số và ứng dụng
Authors: Hoàng, Thị Kim Oanh
Keywords: Bảo vệ bản quyền;Công nghệ thông tin;Kỹ thuật dấu tin
Issue Date: 2006
Publisher: H. : ĐHCN
Citation: 78 tr.
URI: http://repository.vnu.edu.vn/handle/VNU_123/12065
Appears in Collections:Luận văn - Luận án (LIC)

Nhận xét

Đăng nhận xét

Bài đăng phổ biến từ blog này

Composite cylinder under unsteady, axisymmetric, plane temperature field

Nguyen, Dinh Duc Nguyen, Thi Thuy With advantages such as high strength, high stiffness, high chemical resistance, light weight...composite tubes are widely applied in urban construction and petroleum industry. In this report, the authors used the displacement method to study the mechanical behavior (shess, strain...) of an infinite hollow cylinder made of composite material under unsteady, axisymmetric plane temperature field. In the numerical calculations, we mainly studied the influence of time and volume ratio of the particle on the displacement and thermoelastic stress of a cylinder made of Titanium /PVC composite. Chi tiết xin mời tham khảo tại http://repository.vnu.edu.vn/handle/VNU_123/56681   Title:  Composite cylinder under unsteady, axisymmetric, plane temperature field Authors:  Nguyen, Dinh Duc Nguyen, Thi Thuy Keywords:  Composite cylinder;temperature field Issue Date:  2010 Publisher:  H. : ĐHQGHN Series/Report no.:  Vol. 26;N...
Đọc thêm

Structural and magnetic studies of sputtered Fe1-xCrx thin films

N., H. Duc Fnidiki, A Teillet, J X-ray diffraction, magnetization, and Mossbauer effect investigations have been performed for sputtered Fe1-xCrx (0 less than or equal to x less than or equal to 0.54) thin films. The body-centered-cubic (bcc) phase appears for x < 0.32, while the sigma phase is formed for 0.38 less than or equal to x less than or equal to 0.44. For 0.32 less than or equal to x < 0.38 and 0.44 < x less than or equal to 0.54, the samples are composed of both bcc and sigma phases. As the Cr concentration increases, the ferromagnetic fraction, magnetization, and magnitude of the hyperfine field decrease, whereas the magnitude of the isomer shift increases. The Fe and Cr magnetic moments, isomer shift, and hyperfine field of the bcc Fe-Cr phase have been deduced and are discussed consistently in terms of charge and spin distributions, as well as magnetic valence. Chi tiết xin mời tham khảo tại http://repository.vnu.edu.vn/handle/VNU_123/32090   ...
Đọc thêm

Using the Directional Analytic Signals of Magnetic Gradient Tensor to Determine Boundaries of Source

Nguyen, Thi Thu Hang Pham, Thanh Luan Do, Duc Thanh Le, Huy Minh The analytic signals of the magnetic tensor gradient within two-and three-dimensional space can be applied as a useful tool to estimate the depth and position sources because its value characteristics only depend on location but magnetization direction of the sources of the magnetic anomaly [7]. In this paper, we present results of the study for application of the combination of derivatives of directional analytic signals of the magnetic tensor gradient to determine the edges of the sources through the new function Edge-detector (|ED|). Algorithms and programs written in the Matlab language have been used for test calculation on 3D models in correlative comparison with the method using the amplitude function of analytic signals ([2]). The calculation results showed the advantages of the new function |ED| and its applicability in determing the boundaries of sources of magnetic anomaly. Chi tiết xin mời th...
Đọc thêm