The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak （str...The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak （strong） subliminal-free on public-key cryptosystem （PKC） are proposed in this paper using the combinatorial method. The first method can only free the subliminal information with any minor probability and the second can free all. Moreover, the ＂traitor problem＂ which is same as the model of the subliminal channel in PKC is given. Two subliminal channels are embedded in N-th degree truncated polynomial ring （NTRU） cryptosystem, and their subliminal-free methods are also be obtained by the action of surveillant.展开更多
The best hydraulic channel section makes the maximum flow capacity for the same flow cross-area, and the minimum cross-area and wetted perimeter for the same discharge. The construction cost can be reduced nearly to t...The best hydraulic channel section makes the maximum flow capacity for the same flow cross-area, and the minimum cross-area and wetted perimeter for the same discharge. The construction cost can be reduced nearly to the minimum at the same time The horizontal bottom parabolic section （HBP section） is a composite section. It is important for design to find the best combination form of the horizontal bottom and the parabolic sides. This paper studies the best hydraulic section and its hydraulic characteristics. The explicit formulae are proposed to determine the dimensions and the best combination form of the horizontal bottom and the parabolic sides. These explicit formulae and the parameters make it easy to design the channel. It is shown that the ratios of the surface width to the depth and the bottom width to the depth are constant for the best hydraulic section. The comparisons with the classic parabolic, rectangular, trapezoid, triangular, semi-cubic and horizontal-bottomed semi-cubic sections show that the HBP section has the largest flow capacity and the shortest wetted perimeter for the same flow area, and has the smallest flow area for the same discharge. It is indicated that the parabolic side parts of the best hydraulic HBP section are different from those of the classic section. The results of the best hydraulic section of the classic parabolic channel cannot be applied directly to the HBC section.展开更多
A channel section that has minimum construction cost is known as the most economic section.Such a section has important implications for economic efficiency.However,the most economic section is a complex optimization ...A channel section that has minimum construction cost is known as the most economic section.Such a section has important implications for economic efficiency.However,the most economic section is a complex optimization model with nonlinear objective function and constraints that is difficult to use by ordinary engineers.A general simple formula for the most economic section has not been attempted.In this paper,the general differential equation for the most economic section is derived using Lagrange multiplier optimization method.A simple method to solve the most economic section is proposed that converted the optimization model into a general equation for the most economic section of any shape.By solving this equation,the dimensions of the most economic section are directly obtained.To illustrate,the direct formula for trapezoidal section is derived.To aid application in practice,a simple explicit iterative formula for trapezoidal sections is presented.The direct and explicit iterative formulas were validated.The proposed method is superior to the classical optimization method and as such represent a valuable tool for open channel design.To illustrate the versatility of the presented method,a direct formula for the parabolic section was also derived.展开更多
基金Supported by the National Natural Science Foun-dation of China (64073017) the Ph.D.Initial Science Foundationof Guangzhou University (100101) .
文摘The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak （strong） subliminal-free on public-key cryptosystem （PKC） are proposed in this paper using the combinatorial method. The first method can only free the subliminal information with any minor probability and the second can free all. Moreover, the ＂traitor problem＂ which is same as the model of the subliminal channel in PKC is given. Two subliminal channels are embedded in N-th degree truncated polynomial ring （NTRU） cryptosystem, and their subliminal-free methods are also be obtained by the action of surveillant.
基金Project supported by the Key Research and Develop-ment Program of Shandong Province(Grant No.2016GSF117038)the National Science and Technology Su-pport Program of China(Grant No.2015BAB07B02)+1 种基金the Development of Science and Technology Plan of Jinan City,China(Grant No.201302052)the Teaching and Research Projects of the University of Jinan(Grant No.J1641)
文摘The best hydraulic channel section makes the maximum flow capacity for the same flow cross-area, and the minimum cross-area and wetted perimeter for the same discharge. The construction cost can be reduced nearly to the minimum at the same time The horizontal bottom parabolic section （HBP section） is a composite section. It is important for design to find the best combination form of the horizontal bottom and the parabolic sides. This paper studies the best hydraulic section and its hydraulic characteristics. The explicit formulae are proposed to determine the dimensions and the best combination form of the horizontal bottom and the parabolic sides. These explicit formulae and the parameters make it easy to design the channel. It is shown that the ratios of the surface width to the depth and the bottom width to the depth are constant for the best hydraulic section. The comparisons with the classic parabolic, rectangular, trapezoid, triangular, semi-cubic and horizontal-bottomed semi-cubic sections show that the HBP section has the largest flow capacity and the shortest wetted perimeter for the same flow area, and has the smallest flow area for the same discharge. It is indicated that the parabolic side parts of the best hydraulic HBP section are different from those of the classic section. The results of the best hydraulic section of the classic parabolic channel cannot be applied directly to the HBC section.
基金Project supported by the Natural Science Foundation of Shandong Province(Grant No.ZR2017LEE028)the Key Research and Development Program of Shandong Province(Grant No.2016GSF117038).
文摘A channel section that has minimum construction cost is known as the most economic section.Such a section has important implications for economic efficiency.However,the most economic section is a complex optimization model with nonlinear objective function and constraints that is difficult to use by ordinary engineers.A general simple formula for the most economic section has not been attempted.In this paper,the general differential equation for the most economic section is derived using Lagrange multiplier optimization method.A simple method to solve the most economic section is proposed that converted the optimization model into a general equation for the most economic section of any shape.By solving this equation,the dimensions of the most economic section are directly obtained.To illustrate,the direct formula for trapezoidal section is derived.To aid application in practice,a simple explicit iterative formula for trapezoidal sections is presented.The direct and explicit iterative formulas were validated.The proposed method is superior to the classical optimization method and as such represent a valuable tool for open channel design.To illustrate the versatility of the presented method,a direct formula for the parabolic section was also derived.
