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嵩山奇石生因分类及开发前景研究
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作者 张立汉 刘军伟 +2 位作者 袁胜元 高均昭 张谦智 《许昌学院学报》 CAS 2013年第2期118-121,共4页
奇石作为一种特有的矿产资源,首先对嵩山奇石的生因、分类和开发前景进行阐述,接着对嵩山奇石的为了发展前景进行了展望,这对于提高嵩山旅游资源的品格及嵩箕山区的经济发展都有极其重要的作用.
关键词 奇石资源 生因分类 地质作用 嵩山
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Taxonomic reexamination of the genus Chirolophis in China waters
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作者 刘静 田明诚 尤锋 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期199-203,共5页
The present paper deals with the taxonomic reexamination and description of two species of Chirolophis collected in Chinese waters from the Bohai Sea and the Yellow Sea. C. japonicus Herzenstein, 1890 was previously r... The present paper deals with the taxonomic reexamination and description of two species of Chirolophis collected in Chinese waters from the Bohai Sea and the Yellow Sea. C. japonicus Herzenstein, 1890 was previously reported and known by its synonym Azuma emmnion Jordan and Snyder, 1902; C. saitone (Jordan et Snyder, 1902) represents the first record of this species in China from Bohai Sea. A key for their identification and a discussion on all the nominal species and their geographic distribution are provided. 展开更多
关键词 new record TAXONOMY Chirolophis BIOGEOGRAPHY Chinese waters
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Bio-Demographic Factors Impacting on Employment in Namibia: A Binary Logistic Regression Model.
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作者 Camilla Tjikune Lillian Pazvakawambwa 《Journal of Mathematics and System Science》 2013年第9期426-436,共11页
Despite concerted efforts to create employment opportunities and the realized economic growth between 2000 and 2005, the unemployment rate in Namibia currently stands at 27.4%, according to the Labour Force Survey rel... Despite concerted efforts to create employment opportunities and the realized economic growth between 2000 and 2005, the unemployment rate in Namibia currently stands at 27.4%, according to the Labour Force Survey released in April 2013. The percentage of employed males in Namibia stands at 41.6% while that of employed females stand at 28.8% according to the National Human Resources Plan of May 2013. Analysts have put the blame on adverse climatic conditions, limited levels of skills, access to finance, and the structure of the economy. The frustration and discomfort caused by unemployment, especially among the youth, can threaten the country's peace and stability as it negatively impacts on the standard of living, crime rates, family happiness, and drug abuse.To date, studies on employment in Namibia have mainly concentrated on the micro and macro econometric approaches. It is important to examine how bio-demographic characteristics affect employment. This paper uses data from the 2010 Income and expenditure survey to establish the bio-demographic determinants of employment by fitting a binary logistic model. The outcome variable is employment status which is dichotomous. The independent variables which were guided by review of related literature and availability of data in the Income and Expenditure survey data set, included age-group, region, place of residence, marital status, education level, and gender. Results indicated that employment prospects in Namibia were influenced by the region, gender, marital status, and education level. 展开更多
关键词 EMPLOYMENT Namibia logistic regression
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Analysis on the Human Errors in Coal Mines based on Ant Clustering Algorithm
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作者 Shuangyue LIU Zixin FANG 《International Journal of Technology Management》 2013年第1期61-63,共3页
The human error mechanism in coal mine safety is analyzed specifically from safety psychological and physiological factors, worker' s quality, safety management, safety education, mechanical equipment, and working en... The human error mechanism in coal mine safety is analyzed specifically from safety psychological and physiological factors, worker' s quality, safety management, safety education, mechanical equipment, and working environment, and also a human error' dominant factors classification model playing a great effect on the safety production of coal mine is established with the application of ant clustering algorithm. The experimental results show that management is the key in the human errors of coal mine. 展开更多
关键词 Ant Clustering Algorithm Coal Mine Human Errors
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A Graph-theoretic Analysis of Stressors Confronting Giant Panda Habitat across Minshan Mountain Region,China 被引量:1
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作者 肖燚 欧阳志云 +2 位作者 赵景柱 黄宝荣 朱春全 《Journal of Resources and Ecology》 CSCD 2010年第4期339-344,共6页
岷山地区位于四川盆地西北部,是我国生物多样性保护的优先地区,还是保护大熊猫的关键区域。本文以社会-经济-自然复合生态系统为基础,运用图论分析法研究了岷山地区影响大熊猫生境的人类活动方式,以及这些影响因子相互的关系。研究表明... 岷山地区位于四川盆地西北部,是我国生物多样性保护的优先地区,还是保护大熊猫的关键区域。本文以社会-经济-自然复合生态系统为基础,运用图论分析法研究了岷山地区影响大熊猫生境的人类活动方式,以及这些影响因子相互的关系。研究表明:影响大熊猫生境的人类活动的66对组合中,47.0%的因子间存在直接的联系,其中89.2%的影响具有增大效应。这说明人类活动对大熊猫生境的影响具有协同增大效应,并占主导地位。旅游景点开发、公路建设、采矿、高压电线、农业开发、放牧、薪柴采集这些影响因子存在强连通性,它们会将其他人类活动对大熊猫生境的影响放大,加剧对大熊猫生境的不利影响,表明它们是影响岷山地区大熊猫生境的主导人类活动。要想有效地保护岷山地区的大熊猫生境,就必须对这些主导人类活动进行有效的控制。本研究还表明图论分析法有助于明确影响熊猫生境的主导和关键因子,它能为制定有效的大熊猫保护策略提供科学依据。 展开更多
关键词 giant panda habitat anthropogenic stressors graph-theoretic analysis Minshan
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VERTICAL HEREDITY VS. HORIZONTAL GENE TRANSFER: A CHALLENGE TO BACTERIAL CLASSIFICATION 被引量:3
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作者 HAO Bailin(Institute of Theoretical Physics, Academy of Chinese Sciences, Beijing 100080, China Senior International Fellow of the Santa Fe Institute T-Life Research Center, Fudan University,Shanghai 200433, China)QI Ji(Institute of Theoretical Physics, Beijing 100080, China) 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第3期307-314,共8页
The diversity and classification of microbes has been a long-standing issue.Molecular phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable t... The diversity and classification of microbes has been a long-standing issue.Molecular phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable tree of life in the late 1970s. How-ever, the availability of more and more complete bacterial genomes has brought about complications instead of refinement of the tree. In particular, it turns out that different choice of genes may tell different history. This might be caused by possible horizontal gene transfer (HGT) among species. There is an urgent need to develop phylogenetic methods that make use of whole genome data. We describe a new approach in molecular phylogeny,namely, tree construction based on K-tuple frequency analysis of the genomic sequences.Putting aside the technicalities, we emphasize the transition from randomness to determin-ism when the string length K increases and try to comment on the challenge mentioned in the title. 展开更多
关键词 prokaryote phylogeny horizontal gene transfer FITNESS compositionaldistance
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Research advances in animal distant hybridization 被引量:11
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作者 ZHANG ZhuoHui CHEN Jie +6 位作者 LI Ling TAO Min ZHANG Chun QIN QinBo XIAO Jun LIU Yun LIU ShaoJun 《Science China(Life Sciences)》 SCIE CAS 2014年第9期889-902,共14页
Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If prog... Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If progeny derived from distant hybridization are bisexual and fertile,they can form a hybrid lineage through self-mating,with major implications for evolutionary biology,genetics,and breeding.Here,we review and summarize the published literature,and present our results on fish distant hybridization.Relevant problems involving distant hybridization between orders,families,subfamilies,genera,and species of animals are introduced and discussed,with an additional focus on fish distant hybrid lineages,genetic variation,patterns,and applications.Our review serves as a useful reference for evolutionary biology research and animal genetic breeding. 展开更多
关键词 distant hybridization LINEAGE TETRAPLOID TRIPLOID genetic breeding APPLICATION
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4D Graphical representation research of DNA sequences 被引量:1
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作者 Chengjie Tan Shanshan Li Ping Zhu 《International Journal of Biomathematics》 2015年第1期47-58,共12页
Graphical representation of DNA sequences is a key component in studying biological problems. In order to gain new insights in DNA sequences, this paper combined the digitized methods of single-base, base pairs and co... Graphical representation of DNA sequences is a key component in studying biological problems. In order to gain new insights in DNA sequences, this paper combined the digitized methods of single-base, base pairs and coding in triplet bases with the times of base appearing, and then a novel 4D graphical representation method of DNA sequences was put forward. It was a one-to-one correspondence of the arbitrary DNA sequence and 4D graphical representation, that avoided causing non-unique 4D graphical representation and overlapping lines. The method could reflect the biological information features of DNA sequence more comprehensively and effectively without any losses. Based on the 4D graphical representation, we used the geometric center of 4D graphical representation as eigenvalue of DNA sequences analyses, which kept the original features of the data, and then established the Euclidean distances and included angles between vectors' ter- minal point for similarity analyses of the first extron of the beta-globulin gene among 11 species. Finally, we established the graph of systematic hierarchical cluster analysis of 11 species to observe more easily the relationship between species. A positive outcome was reached, and the results were in accord with biological taxonomy, which also supported the rationality and effectiveness of the novel 4D graphical representation. 展开更多
关键词 Euclidean distance graphical representation geometric center similarity analysis.
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