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从应用力学到工程科学 被引量:3
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作者 李家春 《工程研究(跨学科视野中的工程)》 2020年第5期429-434,共6页
工程科学起源于20世纪初德国以普朗特为代表的应用力学学派;20世纪30年代应用力学研究中心转移到美国以冯·卡门为代表的古根海姆空气动力学实验室,钱学森先生师从冯·卡门,在这一领域做出了杰出贡献,并明确提出、系统阐述了工... 工程科学起源于20世纪初德国以普朗特为代表的应用力学学派;20世纪30年代应用力学研究中心转移到美国以冯·卡门为代表的古根海姆空气动力学实验室,钱学森先生师从冯·卡门,在这一领域做出了杰出贡献,并明确提出、系统阐述了工程科学的思想。国内外航空、航天工程的实践已经证明,工程科学可以加速科学革命、经济发展、社会进步。未来工程科学研究领域将从自然现象扩展到生命体乃至人文科学,如:工程管理、工程伦理和工程哲学,并引领交叉学科领域的前沿研究。为适应这一发展趋势,我们将通过强基础、阔领域、重实践、促创新,加速复合型工程科学人才的培养。 展开更多
关键词 工程科学 钱学森 应用力学 航空航天 国科大
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The Genus Rhithrogena Eaton (Ephemeroptera: Heptageniidae) from Chinese Mainland, with Description of a New Species 被引量:1
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作者 周长发 郑乐怡 《Entomotaxonomia》 CSCD 北大核心 2004年第2期81-85,共5页
In present paper the genus Rhithrogena Eaton from Chinese mainland, including a new species to science (Rhithrogena lutea, sp. nov.), 2 new record species from China (R. bajkovae Sowa, R. lepnevae Brodsky) and 3 known... In present paper the genus Rhithrogena Eaton from Chinese mainland, including a new species to science (Rhithrogena lutea, sp. nov.), 2 new record species from China (R. bajkovae Sowa, R. lepnevae Brodsky) and 3 known species [R. wuyinensis (Gui et al.) (comb. nov.), R. trispina Zhou et Zheng, R. orientalis You (= R. sangangensis You, new synonym)] are revised besed on the imaginal specimens. A key to 7 species imagos is provided. All materials in this study are deposited in Nanjing Normal University. 展开更多
关键词 EPHEMEROPTERA HEPTAGENIIDAE Rhithrogena Chinese mainland +
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A new species in the genus Macromotettixoides Zheng(Orthoptera:Tetrigoidea:Metrodoridae) from Sichuan,China 被引量:1
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作者 邓维安 郑哲民 杨瑞刚 《Entomotaxonomia》 CSCD 北大核心 2012年第2期120-122,共3页
A new species of the genus Macromotettixoides Zheng, Macromotettixoides undulatifemura sp. nov. is described from the Emeishan Area of Sichuan, China. Type specimens are deposited at the Institute of Zoology, Shaanxi ... A new species of the genus Macromotettixoides Zheng, Macromotettixoides undulatifemura sp. nov. is described from the Emeishan Area of Sichuan, China. Type specimens are deposited at the Institute of Zoology, Shaanxi Normal University, Xi'an, China. 展开更多
关键词 ORTHOPTERA METRODORIDAE Macromotettixoides new species China
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A Preliminary Study on the Genus Caenis (Ephemeroptera: Caenidae) from Chinese Mainland, with Description of a New Species
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作者 周长发 郑乐怡 《Entomotaxonomia》 CSCD 北大核心 2004年第1期1-7,共7页
Five species of the genus Caenis from Chinese mainland are reviewed. Among them, C. parviforcipis (Zhou et al.) (nov. comb.) is transferred from the genus Brachycercus The larvae of the C. sinensis Gui et al. are desc... Five species of the genus Caenis from Chinese mainland are reviewed. Among them, C. parviforcipis (Zhou et al.) (nov. comb.) is transferred from the genus Brachycercus The larvae of the C. sinensis Gui et al. are described for the first time. The previously reported C. nigroforceps Zhou et al. is recognized as a new synonym of the Caenis rivulorum Eaton, and the report of C. nigropunctata Klapálek from China is confirmed. Both imagos and larvae of a new species C. melanoleuca, sp. nov. are described and illustrated in detail. 展开更多
关键词 EPHEMEROPTERA Caenidae Caenis REVISION Chinese mainland
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钻井液设计专家系统规则库的检测算法 被引量:3
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作者 李建 习文风 《计算机工程与应用》 CSCD 北大核心 2020年第4期256-261,共6页
钻井液设计专家系统规则库的规模随着规则的更新与日俱增,对规则库的维护工作变得日益重要。针对规则库的从属、冗余、环路和冲突等问题提出一种检测算法。引入有向超图来表示规则库中的规则;用邻接矩阵表示该有向超图,并计算出它的可... 钻井液设计专家系统规则库的规模随着规则的更新与日俱增,对规则库的维护工作变得日益重要。针对规则库的从属、冗余、环路和冲突等问题提出一种检测算法。引入有向超图来表示规则库中的规则;用邻接矩阵表示该有向超图,并计算出它的可达矩阵和总可达矩阵;用总可达矩阵对规则库进行检测,找出规则库中存在的问题。实验表明,与已有的检测算法相比,该算法能够有效地检测出规则库中存在的问题,同时构建的邻接矩阵规模较小,在保证算法简洁的基础上提高了效率。 展开更多
关键词 专家系统 规则库 有向超图 邻接矩阵 可达矩阵 总可达矩阵
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Trends in Seasonal Precipitation over China during 1961-2007 被引量:14
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作者 WANG Yi YAN Zhong-Wei 《Atmospheric and Oceanic Science Letters》 2009年第3期165-171,共7页
Trends in six indices of precipitation in China for seasons during 1961-2007 were analyzed based on daily observations at 587 stations. The trends were estimated by using Sen's method with Mann-Kendall's test ... Trends in six indices of precipitation in China for seasons during 1961-2007 were analyzed based on daily observations at 587 stations. The trends were estimated by using Sen's method with Mann-Kendall's test for quantifying the significance. The geographical patterns of trends in the seasonal indices of extremes were similar to those of total precipitation. For winter, both total and extreme precipitation increased over nearly all of China, except for a small part of northern China. Increasing trends in extreme precipitation also occurred at many stations in southwestern China for spring and the midlower reaches of the Yangtze River and southern China for summer. For autumn, precipitation decreased in eastern China, with an increasing length of maximum dry spell, implying a drying tendency for the post-rainy season. Wetting trends have prevailed in most of western China for all seasons. The well-known 'flood in the south and drought in the north' trend exists in eastern China for summer, while a nearly opposite trend pattern exist for spring. 展开更多
关键词 climate trend climate extremes indices PRECIPITATION dry spell China
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Calibration and Validation of an All-Sky Imager 被引量:3
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作者 HUO Juan LU Da-Ren 《Atmospheric and Oceanic Science Letters》 2009年第4期220-223,共4页
The automatic all-sky imager developed by the Institute of Atmospheric Physics,Chinese Academy of Sciences,provides all-sky visible images in the red,green,and blue channels.This paper presents three major cali-bratio... The automatic all-sky imager developed by the Institute of Atmospheric Physics,Chinese Academy of Sciences,provides all-sky visible images in the red,green,and blue channels.This paper presents three major cali-bration experiments of the all-sky imager,geometric an-gular calibration,optical calibration,and radiometric calibration,and then infers an algorithm to retrieve rela-tive radiance from the all-sky images.Field experiments show that the related coefficient between retrieved radi-ance and measured radiance is about 0.91.It is feasible to use the algorithm to retrieve radiance from images.The paper sets up a relationship between radiance and the im-age,which is useful for using the all-sky image in nu-merical-simulations that predict more meteorological pa-rameters. 展开更多
关键词 ALL-SKY VISIBLE image RADIANCE CLOUD
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Climatology and Trends of High Temperature Extremes across China in Summer 被引量:8
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作者 WEI Ke CHEN Wen 《Atmospheric and Oceanic Science Letters》 2009年第3期153-158,共6页
Based on the daily maximum air temperature data from 300 stations in China from 1958 to 2008, the climatological distribution of the number of days with high temperature extremes (HTEs, maximum temperatures higher th... Based on the daily maximum air temperature data from 300 stations in China from 1958 to 2008, the climatological distribution of the number of days with high temperature extremes (HTEs, maximum temperatures higher than 35℃) are studied with a focus on the long-term trends. Although the number of HTE days display well-defined sandwich spatial structures with significant decreasing trends in central China and increasing trends in northern China and southern China, the authors show that the decrease of HTE days in central China occurs mainly in the early period before the 1980s, and a significant increase of HTE days dominates most of the stations after the 1980s. The authors also reveal that there is a jump-like acceleration in the number of HTE days at most stations across China since the mid 1990s, especially in South China, East China, North China, and northwest China. 展开更多
关键词 high temperature extremes hot days long term trend climate regime
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The spirit of Henry Norman Bethune and gastroenterology 被引量:1
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作者 Hugh J Freeman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期174-179,共6页
Henry Norman Bethune was a physician and surgeon from Canada. He had a highly impressive medical career in Montreal but did his most important work in China where he cared for soldiers on the battlefield. He died in 1... Henry Norman Bethune was a physician and surgeon from Canada. He had a highly impressive medical career in Montreal but did his most important work in China where he cared for soldiers on the battlefield. He died in 1939 and was recognized as a hero, but only much later received recognition in Canada. He was a skilled doctor, both as a physician and as a surgeon. However, he was much more and will serve as an inspiration for this series. He was an innovator, an idealist and a perfectionist. It is hoped that this series will gather expert commentaries on a range of issues critical to the subspecialty from fundamental science to clinical care so that future directions can be defined. 展开更多
关键词 Bethune GASTROENTEROLOGY China CANADA Battlefield surgery
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Study on the efficiency of equipment shared by universities 被引量:1
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作者 WANG Hong-da 《Chinese Business Review》 2007年第4期46-51,共6页
Based on the theory of data envelopment analysis, this paper sets up the super-efficiency data envelopment analysis (DEA) model. It makes use of the model to evaluate efficiency of equipment shared by universities i... Based on the theory of data envelopment analysis, this paper sets up the super-efficiency data envelopment analysis (DEA) model. It makes use of the model to evaluate efficiency of equipment shared by universities in Tianjin. It explored database of many universities and put forward suggestions to improve the efficiency of equipment shared by universities at present. 展开更多
关键词 data envelopment analysis (DEA) UNIVERSITY SUPER-EFFICIENCY
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Synchronous incidental gastrointestinal stromal and epithelial malignant tumors 被引量:24
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作者 Yan-Jun Liu Zhou Yang +3 位作者 Lang-Song Hao Lin Xia Qian-Bin Jia Xiao-Ting Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第16期2027-2031,共5页
AIM:To investigate the incidence of incidental gastrointestinal stromal tumor (GIST) and its etiopathogenesis.METHODS: From January 1, 2000 to December 31, 2007, 13 804 cases of gastrointestinal epithelial malignant t... AIM:To investigate the incidence of incidental gastrointestinal stromal tumor (GIST) and its etiopathogenesis.METHODS: From January 1, 2000 to December 31, 2007, 13 804 cases of gastrointestinal epithelial malignant tumor (EMT) and 521 cases of pancreatic adenocarcinoma (PAC) were successfully treated with surgery at the Department of General Surgery and the Department of Thoracic Surgery, West China Hospital, Sichuan University, China. The clinical and pathologic data of 311 cases of primary GIST, including 257 cases with clinical GIST and 54 cases of incidental GIST were analyzed.RESULTS: Of the 311 patients, 54 had incidental GIST, accounting for 17.4%. Of these tumors, 27 were found in 1.13% patients with esophageal squamous cell carcinoma (ESCC), 22 in 0.53% patients with gastric adenocarcinoma (GAC), 2 in 0.38% patients with PAC, 2 in 0.03% patients with colorectal adenocarcinoma, and 1 in one patient with GAC accompanying ESCC, respectively. Patients with incidental GIST presented symptoms indistinguishable from those with EMT. All incidental GIST lesions were small in size, and the majority had a low mitotic activity while only 1.9% (5/257) of clinical GIST lesions had a high risk.CONCLUSION: Incidental GIST may occur synchronously with other tumors and has a high prevalence in males. Surgery is its best treatment modality. 展开更多
关键词 Gastrointestinal stromal tumor Multitumor Synchronous tumor
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Identity, the Main Term of Contrast between "Globalization" and "Universalization" An Interpretention with a Critical Linguistic Approach
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作者 Mohammad Tohidfam Maryam Khosravi Baraghani Shahab Dalili 《Journal of Philosophy Study》 2016年第3期155-161,共7页
Communicational and international developments have different aspects in today's world so that some terms like "Internationalization," "Liberalization," "Universalization," "Westernization," "Deterritorializ... Communicational and international developments have different aspects in today's world so that some terms like "Internationalization," "Liberalization," "Universalization," "Westernization," "Deterritorialization" find interferences in social sciences and humanities studies. But these terms can generally be distinguished by two different categories of study as some experts have emphasized that the above developments are in the process (Globalization) while the others considered them on the project (To Globalize). The main problem is that how we can find out the focal point of both studies through which the accuracy of these claims to be verified to know whether contemporary changes and evolutions are formed in a process or a project. It seems that the focal point in the sphere of both claims (processes and projects) is the issue of "identity" since both spheres agree that the concept of "identity" has passed a series of changes and developments, although each one renders the path and goal of "identity" changes by its own specific interpretations. In this article, we claim that using linguistic approach we are able to review the developments and evolutions' flow of identity in the present era and thereby it can be found that the developments in information and communication would lead to creating a process in the context of Globalization or a project on Universalization. The assumption of this study is that by explanation of the above-mentioned situation, we can see that based on the linguistic approach, the process of making identity is "context-based" and "conditional" as opposed to a project view formation and relative continuity of identification process would generally be subject to the condition. 展开更多
关键词 IDENTITY GLOBALIZATION UNIVERSALIZATION LINGUISTICS proximity conditionality and contextualism
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Development of Solid Oxide Fuel Cell Technology at the Institute of Nuclear Energy Research
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《Journal of Physical Science and Application》 2013年第3期175-183,共9页
This paper shows the development of solid oxide fuel cell (SOFC) technology at the Institute of Nuclear Energy Research. In the development, fabrication processes for planar anode-supported-cell (ASC) by conventio... This paper shows the development of solid oxide fuel cell (SOFC) technology at the Institute of Nuclear Energy Research. In the development, fabrication processes for planar anode-supported-cell (ASC) by conventional methods and metal-supported-cell (MSC) by atmospheric plasma spraying are well established. Procedures and techniques for stacking and cell/stack performance tests are continuously improved to enhance the quality and reliability. Innovative nano-structured catalysts, in which reduced Pt and CeOz particles dispersed onto the A120~ carriers can effectively prevent the migration and coalescence of the metal crystallites, are thermal stable and possess a conversion ratio higher than 95% for reforming of natural gas. A non-premixed after-burner/reformer is designed and fabricated, and it has passed the prerequisite functional tests. Layouts including stacks, components of BOP, power conditioning and control as well as gases and water supply, are designated for a 1-kW SOFC power system. In compliance with system requirements, operating modes, data acquisition, power conditioning, instrumentations, and control logics have been identified and settled. After successive system validation tests, two modules of 18-cell stacks are allocated into the SOFC system. Test results indicate a thermal self-sustaining system on natural gas is achieved with a power output of around 760 watts. 展开更多
关键词 SOFC ASC MSC STACK system.
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Conclusions on the Implementation of Regulation of the National Significant Seismic Monitoring and Protection Regions from 1996 to 2012 in the Chinese Mainland
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作者 Chao Hongtai Gao Mengtan +7 位作者 Li Bo Chen Shijun Liang Kaili Ma Yuxiang Wang Feng Wu Guochun Lang Cong Wu Xinyan 《Earthquake Research in China》 CSCD 2015年第1期8-20,共13页
The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.T... The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR. 展开更多
关键词 The National Significant Seismic Monitoring and Protection Regions Legalregulation Effect and progress Measures on protecting against andmitigating earthquake disasters
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A Glance at Science-Related Museums on the Chinese Mainland
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作者 Jiao Zhengshan 《Chinese Annals of History of Science and Technology》 2019年第1期74-86,共13页
Science-related museums are a special kind of museum concerned with science,technology,the natural world,and other relevant issues.On the Chinese mainland,the emergence and development of science-related museums have ... Science-related museums are a special kind of museum concerned with science,technology,the natural world,and other relevant issues.On the Chinese mainland,the emergence and development of science-related museums have been influenced by both Western culture and Chinese culture and society.These museums,which include science and technology museums,science centers,specialized museums,and scientific sites,play multiple roles,acting as bases for popular science and patriotic education,research institutes,etc.Today,such museums are attracting more and more public and scholarly attention. 展开更多
关键词 Science-related museums the Chinese mainland HISTORY
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Transnational Mathematics and Movements: Shiingshen Chern, Hua Luogeng, and the Princeton Institute for Advanced Study from World War II to the Cold War 被引量:2
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作者 Zuoyue Wang Guo Jinhai 《Chinese Annals of History of Science and Technology》 2019年第2期118-165,共48页
This paper reconstructs,based on American and Chinese primary sources,the visits of Chinese mathematicians Shiing-shen Chern陈省身(Chen Xingshen)and Hua Luogeng华罗庚(Loo-Keng Hua)4 to the Institute for Advanced Study... This paper reconstructs,based on American and Chinese primary sources,the visits of Chinese mathematicians Shiing-shen Chern陈省身(Chen Xingshen)and Hua Luogeng华罗庚(Loo-Keng Hua)4 to the Institute for Advanced Study in Princeton in the United States in the 1940s,especially their interactions with Oswald Veblen and Hermann Weyl,two leading mathematicians at the IAS.It argues that Chern’s and Hua’s motivations and choices in regard to their transnational movements between China and the US were more nuanced and multifaceted than what is presented in existing accounts,and that socio-political factors combined with professional-personal ones to shape their decisions.The paper further uses their experiences to demonstrate the importance of transnational scientific interactions for the development of science in China,the US,and elsewhere in the twentieth century. 展开更多
关键词 Shiing-shen Chern Chen Xingshen Hua Luogeng Loo-Keng Hua Institute for Advanced Study Princeton Oswald Veblen Hermann Weyl J.Robert Oppenheimer mathematics transnational science China United States World War II Cold War
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Self-Regulated Reading Comprehension Strategy Selection Through Diagnostic-Prescriptive Instruction: A Case Study
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作者 Kelly M. Parker 《Sociology Study》 2015年第10期768-774,共7页
This demonstration of concept applies diagnostic-prescriptive reading instruction, a methodology useo m omteu atd^u~ developmental education, toward improving reading comprehension and self-regulated comprehension str... This demonstration of concept applies diagnostic-prescriptive reading instruction, a methodology useo m omteu atd^u~ developmental education, toward improving reading comprehension and self-regulated comprehension strategy selection in Chinese postsecondary education. A single tutor, also the researcher, works closely with one Chinese university student to develop student-centered comprehension strategies that she can practice on her own. After a battery of formal and informal assessments and interviews, decoding and understanding deficiencies are identified, characterized, and discussed. Both the student and her tutor develop and execute a study plan, which was completed during the spring semester of 2010 at Sha'anxi University of Science and Technology (SUST) in Xi'an, People's Republic of China (PRC). By focusing on the subject's primary decoding deficiency, spelling, and her primary understanding deficiency, lack of background knowledge, the subject and her reading tutor are able to strategically tackle five reading comprehension goals: (1) spelling; (2) phonemic awareness; (3) noticing structural and cohesive elements; (4) comparing argumentative and evaluative texts; and (5) analyzing expository texts in business and economics. A final discussion analyzes both qualitative and quantitative data, including unexpected discoveries such as the salience of cohesion in reading comprehension and the cultural biases of standardized reading assessments. 展开更多
关键词 READING COMPREHENSION SELF-REGULATION diagnostic-prescriptive strategies
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Quantum Key Distribution without Signal Disturbance Monitoring
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《Bulletin of the Chinese Academy of Sciences》 2015年第4期235-235,共1页
Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed a... Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment. 展开更多
关键词 switching robin disturbance intellectual verified correctly Photonics compromise interferometer independence
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Future of Public Relations Curriculum: Searching for the Ideal Undergraduate Public Relations Curriculum
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作者 Jinbong Choi 《Journalism and Mass Communication》 2012年第10期989-997,共9页
This study analyzes the public relations curricula of 44 American colleges that have a Public Relations (PR) Student Society of America (PRSSA) chapter. Through content analysis, this study examines general requir... This study analyzes the public relations curricula of 44 American colleges that have a Public Relations (PR) Student Society of America (PRSSA) chapter. Through content analysis, this study examines general requirements, core public relations courses, requirements of public relations programs and strategic communication programs, and optional public relations courses offered by the colleges. The findings of this study reveal that very few public relations programs offer courses involving new media, crisis communication, and PR ethics. In order to keep in touch with the fast-changing public relations landscape, more PR programs should require and integrate new media, crisis communication and ethics courses. 展开更多
关键词 PR curriculum strategic communication American college PR ethics Public Relations Student Society of America (PRSSA)
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The Road to Self-Reliance of the First French Atomic Bomb
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作者 LI Yunyi 《Chinese Annals of History of Science and Technology》 2022年第2期120-147,共28页
After World War II,the choice of the plutonium bomb as the technology roadmap for the first French atomic bomb was not a military issue,but rather one guided by civilian nuclear technology policy.After consideration o... After World War II,the choice of the plutonium bomb as the technology roadmap for the first French atomic bomb was not a military issue,but rather one guided by civilian nuclear technology policy.After consideration of the amount of uranium to be mined,technical reserves,and the financial situation,the civilian nuclear energy project of the Commissariatàl’énergie Atomique(CEA)was based on plutonium and natural uranium as the fissile materials,which indirectly provided enough plutonium for the future development of a nuclear weapon.When the Fourth Republic decided to develop the atomic bomb,a“Common Core”was established with the CEA,a public institution,as the lead,assisted by the military.Faced by the US embargo of nuclear weapons technology,the co-existence of civilian and military branches and their collaboration to some degree in the CEA not only made it a civilian-military complex,but also facilitated breakthroughs in the core technologies of implosion,the plutonium core,the tamper,and the neutron source.The success of the first French nuclear weapons test on February 13,1960,announced that France was on its way to becoming self-reliant in the military use of nuclear science. 展开更多
关键词 SELF-RELIANCE first French atomic bomb Commissariatàl’énergie Atomique(CEA) Big Science Project
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