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A Robust Chaos-Based Image Cryptosystem with an Improved Key Generator and Plain Image Sensitivity Mechanism

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Journal of Information Security 2017年第1期8卷 23-41页

作者： Hidayet Ogras Mustafa türk Department of Electrical Education Batman UniversityBatmanTurkey Department of Electrical and Electronics Engineering Firat UniversityElazigTurkey

In this paper, we propose an effective gray image cryptosystem containing Arnold cat map for pixel permutation and an improved Logistic map for the generation of encryption keys to be used for pixel modification. Firstly, a new chaotic map is designed to show better performance than the standard one in terms of key space range, complexity and uniformity. Generated secret key is not only sensitive to the control parameters and initial condition of the improved map but also strongly depend on the plain image characteristic which provides an effective resistance against statistical and differential attacks. Additionally, to get higher encryption strength of the cryptosystem, both confusion and diffusion processes are performed with different keys in every iterations. theoretical analysis and simulation results confirm that the proposed algorithm has superior security and effectively encrypts and decrypts the gray images as well.

关键词： Chaos Image Cryptosystem Logistic Map Diffusion Arnold Cat Map

Groundwater Quality and Arsenic Contamination in Amphoe Khemmarat, Ubon Ratchathani, thailand

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Journal of Environmental Science and Engineering(A) 2012年第2期1卷 133-141页

作者： Pranee Pattanapipitpaisal t Piyada Suraruk BioremediationLaboratory DepartmentofBiologyScienceFacultyofScienceUbonRatchathaniUniversityUbonRatchathani34910Thailand

Arsenic （As） is one of the most important elemental pollutants in groundwater and drinking water because it causes health problem of arsenicosis after consumption of drinking arsenic-rich water more than 5-10 years. Arsenic contamination of groundwater is an emerging issue in Mekong Basin including Cambodia, Vietnam, and thailand. In thailand, information about arsenic contamination in drinking water resources are quite rare due to that arsenic is not the main element in water qualification assay. the objective of this study is to determine groundwater quality and arsenic contamination in rural Mekong Basin, Ubon Ratchathani. Groundwater samples were collected from 20 different sampling points, between August 2009 and February 2010 in Amphoe Khemmarat, Ubon Ratchathani, thailand. Physical and chemical characteristics of groundwater were determined. It was observed that the groundwater was 27.9-30.3 ~C, pH 5.7-6.9. the conductivity was 707-767 ***＂. Dissolved oxygen was 2.04-5.12 mg.L-1 and tDS was 352-384 mg.L~. the samples showed soft- to very hardness-water properties. In some area, few parameters like CI, Fe, Mn, and As exceeded the WHO guideline limits. this result represents basic information for quality of groundwater and the arsenic contamination in rural Mekong Basin, Ubon Ratchathani. thus, it is probably useful for arsenic standard level assignment and public health authorities. Moreover, it also leads to establish research activity in treatment of arsenic-contaminated groundwater for different purposes

关键词： Arsenic arsenic contamination groundwater quality.

A Comparative Analysis of IPO Performance for Firms in China's Mainland and Hong Kong SAR

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World Economy & China 2001年第4期9卷 52-58页

作者： Louis t.W.Cheng Associate Professor of Finance

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Single iron sites for catalytic, nonoxidative conversion of methane

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Science China Chemistry 2014年第7期57卷 923-923页

作者： Alexis t. Bell University of California

the availability of inexpensive natural gas from the fracturing of shale and as a byproduct of oil production has stimulated the investigation of catalytic processes for the direct conversion of methane to products. Efforts in this direction are further driven by the desire to avoid the generation of CO2 and its emission to the atmosphere, as occurs when methane is steam-retbrmed to produce synthesis gas, a mixture of CO and H2 that can be used for the production of fuels and chemicals via Fischer-tropsch synthesis. During the past forty years, numerous investigators have attempted to convert methane to higher value products by either thermal dehydrogenation or by oxidative dehydrogenation. While methane can be converted to benzene and hydrogen via thermal dehydrogenation,

关键词：甲烷转化催化过程非氧化站点石油生产氧化脱氢直接转换副产品

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Stereoselective Synthesis of 2,3,4,6-tetrasubstituted tetrahydropyrans

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有机化学 2003年第Z1期23卷 382-383页

作者： GONG Jun-Fang WU Yang-Jie Véronique Micheletb Jean-Pierre Genêt b Department of Chemistry Zhengzhou University Zhengzhou 450052 Department of Chemistry Zhengzhou University Zhengzhou 450052 Laboratoire de Synthèse Sélective Organique et Produits Naturels E. N. S. C. P. UMR 7573 11 rue P. et M. Curie F- 75231 Paris Cedex 05 France Laboratoire de Synthèse Sélective Organique et Produits Naturels E. N. S. C. P. UMR 7573 11 rue P. et M. Curie F- 75231 Paris Cedex 05 France

　　the construction of stereodefined, highly substituted tetrahydropyrans has attracted a lot of interest over the years since they constitute ubiquitous fragments of numerous biologically active natural products.[1] During the course of our synthetic studies toward ambruticin, a fascinating antibiotic[2] which came back in the front scene with three recent total synthesis, [3] we have been interested in the synthesis of 2,3,4,6-tetrasubstituted tetrahydropyrans 5 (Scheme 1). [4] Moreover, this kind of subunit is found to be embedded in several other natural products such as lasonolide A, polycavernoside A, ratjadone, or concanamycin A.……

关键词： natural products total synthesis

倾听自然的回响 Dagmar Štěpánová访谈录

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室内设计与装修 2021年第4期 97-98页

作者： DagmarŠtěpánová Formafatal建筑工作室

id+c:对于捷克设计,大多数中国设计师都比较陌生,您能简单介绍一下捷克的设计行业现状吗?Dagmar Štěpánová:捷克有着非常卓越的设计水平,捷克的设计师在国内外也曾获得无数殊荣,例如红点奖等极具影响力的国际奖项。而这一切都与捷克... 详细信息

id+c:对于捷克设计,大多数中国设计师都比较陌生,您能简单介绍一下捷克的设计行业现状吗?Dagmar Štěpánová:捷克有着非常卓越的设计水平,捷克的设计师在国内外也曾获得无数殊荣,例如红点奖等极具影响力的国际奖项。而这一切都与捷克当地的生产质量、新的技术及工艺息息相关。众所周知,捷克的玻璃制造业远近闻名,高超的技艺享誉全球。

关键词：行业现状国际奖项捷克设计师影响力

FOSt PALEOZOIC FORMAtIONS OF tHE MN YIN AND LAI WU VALLEYS OF SHANtUNG.

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地质学报 1923年第Z1期 29-33页

作者： H.C.t’AN

INtRODUCtION. I was appointed to accompany Dr. J. G. Andersson to take a trip incentral Shantung. especially in Men Yin (蒙阴) and Lai Wu (莱芜),valleys,for the purpose of collecting fossils and observing the post-Pal... 详细信息

关键词： FOSt PAL N YIN AND LAI WU VALLEYS OF SHANtUNG EOZOIC FORMAtIONS OF tHE M

Galactic Structure and Holography

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Journal of Modern Physics 2017年第14期8卷 2179-2188页

作者： t. R. Mongan 84 Marin Avenue Sausalito CA USA

Galactic structure, involving bulk motion of matter conserving mass and angular momentum, is analyzed in a holographic large scale structure model. In isolated galaxies, baryonic matter inhabits dark matter halos with holographic radii determined by total galactic mass. the existence of bulgeless giant spiral galaxies challenges previous models of galaxy formation. In sharp contrast, holographic analysis is consistent with the finding that 15% of a sample of 15,000 edge-on disk galaxies in the sixth SDSS data release are bulgeless. Holographic analysis also indicates that E7 ellipticals are less than 2% of elliptical galaxies.

关键词： Galactic Structure Holography

the Uncleaved Signal Peptide Determines the Nonclassical N-glycosylation of BmNPV GP64

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The Uncleaved Signal Peptide Determines the Nonclassical N-g...