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互易定理适用的充要条件 被引量:2
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作者 刘建东 《大学物理》 1999年第11期25-27,共3页
给出互易定理适用于无独立源线性定常网络的充分必要条件
关键词 易条件 定理 线性电路 弃要条件
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互易定理的适用条件
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作者 刘建东 《张家口师专学报(自然科学版)》 1992年第1期36-41,共6页
提出了互易定理的适用条件。论证了互易性和无源性是毫不相干的两个概念。
关键词 定理 适用条件 易条件 无源性 线性网络 特勒根定理
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数学题“隐含条件”的创设的几点建议
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作者 余新军 《数学学习与研究》 2011年第9期39-39,共1页
在数学教学中,设制隐含条件的目的就是加深题目的难度,从而能很好地考查学生对基础知识的掌握程度以及考查学生的观察能力和分析能力.因此,研究隐含条件的设制,很有必要.
关键词 特定条件 特定图形 条件
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山东滨州滨城区小麦条锈病的发生与防治 被引量:1
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作者 梁金霞 《农业工程技术》 2022年第23期47-48,共2页
小麦条锈病是山东省滨城市滨城区小麦种植中的常见病害,易造成较大损失,需提高重视程度,加强病害防治。该文介绍了滨城区小麦条锈病的发病症状,分析了病害发生规律与原因,并根据感染条件,针对性提出优选抗病良种、加强田间管理、综合防... 小麦条锈病是山东省滨城市滨城区小麦种植中的常见病害,易造成较大损失,需提高重视程度,加强病害防治。该文介绍了滨城区小麦条锈病的发病症状,分析了病害发生规律与原因,并根据感染条件,针对性提出优选抗病良种、加强田间管理、综合防治、加强病情监测预报等防治建议,以期实现当地小麦的优质高产。 展开更多
关键词 小麦 条锈病 发病症状 发生规律 发生原因 条件 综合防治 监测 预报
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Research on Cultivating Dynamic Comparative Advantag.es of Chinese Industries
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作者 王岳平 《China Economist》 2013年第3期16-25,共10页
This paper theoretically analyzes the lock-in mechanism of labor division for developing countries when they stick to static comparative advantages and the internal mechanism of cultivating dynamic comparative advanta... This paper theoretically analyzes the lock-in mechanism of labor division for developing countries when they stick to static comparative advantages and the internal mechanism of cultivating dynamic comparative advantages. Through empirical analysis, this paper finds that China, while sharing the benefits of globalization, showcases the lock-in effect regarding its status in the international labor division chain. The analysis finds that in its participation in globalization, the net barter terms of trade ~BTT) and factorial terms of trade for China are deteriorating, and the income terms of trade are seriously overvalued, resulting in a series of contradictions, such as scanty returns for enterprises, slow income growth, increasing trade frictions, and intensified environmental and resource pressures. The paper analyzes rapidly changing factors in China's comparative advantages and characteristics of the changes in industries where China possesses comparative advantages. According to changes in different types of industries at different stages, this paper puts forward suggestions on direction and policies for cultivating dynamic comparative advantages. 展开更多
关键词 comparative advantage INDUSTRY terms of trade
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A study of environmental impact on manufacturing products trade in Shandong,China
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作者 LI Jing-mei LIN Yan-zhen Randy J.RUNNELS 《Ecological Economy》 2010年第2期152-160,共9页
Based on the situation that the trade of manufactured goods takes the main position in Shandong Province,this paper identifies Shandong industrial pollutant discharge by three indices,which are industrial effluent dis... Based on the situation that the trade of manufactured goods takes the main position in Shandong Province,this paper identifies Shandong industrial pollutant discharge by three indices,which are industrial effluent discharge,industrial SO2 emission,and solid waste disposal.Furthermore,it conducts an empirical analysis of the trade terms of pollution content transfer on nine identified industrial sectors.The conclusion is that the increase in industrial effluent discharge,industrial SO2 emission,and solid waste disposal has paralleled the growth of the GDP in Shandong.The rapid economic growth brings obvious negative impact on the environment.Compared with that in 1998,the increase in the pollution content of exports in 2007 indicated that more environmental costs were generated with the economic development in Shandong.There is a need for optimization of foreign trade structure in Shandong,especially the need for increasing import of the pollution intensive products and decreasing the export of the pollution intensive products.The research on the relationship between manufactured goods trade and the environmental impact will make a contribution to the adjustment of foreign trade and environmental policies. 展开更多
关键词 Manufactured goods Foreign trade Environmental impact Trade terms of Pollution content transfer
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The Global Fur Industry: Trends, Globalization and Specialization
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作者 Henning Otte Hansen 《Journal of Agricultural Science and Technology(A)》 2014年第7期543-551,共9页
The fur industry and the entire fur cluster are in many ways an interesting and instructive example from which many lessons can be learned. Up to now, the international fur industry has not been thoroughly described o... The fur industry and the entire fur cluster are in many ways an interesting and instructive example from which many lessons can be learned. Up to now, the international fur industry has not been thoroughly described or analyzed. A major reason is the rather limited availability of national and international statistics about the fur sector. This article analyzes the production and international trade in fur based on information from official statistics, trade associations, companies, scientific papers and reports, interviews with experts, etc.. Markets and market conditions play a very important role with regards to the fur sector, and the price of fur is volatile in the short and long run. A new world trade pattern and international specialization have emerged in recent years. The comparative advantages of the fur sector change along the fur value chain, while China's position on the global fur market has changed significantly. 展开更多
关键词 Fur industry mink production fur garment international trade fur cluster.
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One-pot Synthesis of 6-Hydroxyhexanoic Acid from Cyclohexanone Catalyzed by Dealuminated HBEA Zeolite with Aqueous 30% H_2O_2 Solution
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作者 Xia Changjiu Yang Yongjia +6 位作者 Zhao Yi Lin Min Zhu Bin Peng Xinxin Dai Zhenyu Luo Yibin Shu Xingtian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第3期1-6,共6页
The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized con... The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized conditions,the cyclohexanone conversion and 6-hydroxyhexanoic acid selectivity are over 95%, respectively. The excellent catalyticperformance is attributed to the activation of carbonyl group of cyclohexanone and the fast hydrolysis and ring opening ofs-caprolactone by both Lewis acid and Br0nsted acid sites under aqueous conditions. 展开更多
关键词 Baeyer-Villiger oxidation cyclohexaxlone 6-hydroxyhexanoic acid ZEOLITE HYDROLYSIS
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Comparison of Efficiencies of Enterprises Engaged in Food Sector in Turkey by Data Envelopment Analysis Taking Account of Their Efficiencies and Rantability Rates
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作者 Filiz Cakir Zeytinoglu Sezayi Dumanoglu Mert Uydaci 《Journal of Modern Accounting and Auditing》 2011年第2期182-192,共11页
Enterprises are in competition with other enterprises operating in their fields. In today's world, enterprises need to increase their efficiency and productivity, the values of which, if below market conditions, they... Enterprises are in competition with other enterprises operating in their fields. In today's world, enterprises need to increase their efficiency and productivity, the values of which, if below market conditions, they need to raise. Data Envelopment Analysis, widely utilized in efficiency and productivity measurements is a method that measures the efficiency of one unit relatively, taking more than one input determines the efficiency of units with similar inputs and outputs and output simultaneously. DEA interactively Thus, not only the efficient units are determined, but an opinion is offered as to how the inefficient units can be improved. In this study, 12 enterprises that were among the first 500 enterprises in Turkey in 2008, active in Istanbul Stock Exchange and operating in food sector through Data Envelopment Analysis. In the model, activity rates were used as input values, rantability rates were used as output values. In conclusion of simultaneous analysis of input and output values, efficient and inefficient enterprises were determined. 展开更多
关键词 data envelopment analysis decision making units CCR BCC consumption cooperatives retailing
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大国崛起失败的国际政治经济学分析 被引量:19
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作者 冯维江 张斌 沈仲凯 《世界经济与政治》 CSSCI 北大核心 2015年第11期4-35,156,共32页
在特定的文化与制度环境内,受具体政策的影响,如果一国能够实现有效的资源配置,在发挥其禀赋的生产性比较优势的同时,对国内外不安全因素予以有效震慑和遏制,则该国能够获得持续的经济增长而不断崛起。崛起中的大国的国内民众或利益集... 在特定的文化与制度环境内,受具体政策的影响,如果一国能够实现有效的资源配置,在发挥其禀赋的生产性比较优势的同时,对国内外不安全因素予以有效震慑和遏制,则该国能够获得持续的经济增长而不断崛起。崛起中的大国的国内民众或利益集团及国际盟友或伙伴国的过度期待与要求以及它与当前处于支配性地位的霸权国之间紧迫的竞争,为战略性误判/误导的发生准备了环境性条件。所谓战略性误判,是指那些可能造成资源严重错配的政策与行动所依据的判断。由于大国博弈性和竞争紧迫性的存在以及内部特殊利益集团的影响,许多误判实际上是战略性误导的结果。从德国、苏联和日本等大国崛起失败的案例来看,决策集中、社会动员力高、国内利益集团分化等体制性条件,更容易诱发战略性误判/误导并造成更严重的资源错配后果,以致崛起国在内忧外患下突然溃败。科学的试错机制、开放的经济体系、良好的国际关系和中性的权威政府能够避免或至少减轻战略性误导/误判的不利影响。 展开更多
关键词 大国崛起失败 战略性误导 条件 资源错配
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外贸知识讲座 如何与外商订立海外经销合同和代理合同——第十四讲 代理合同的条文示例(第18~24条)
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作者 王秀 《世界机电经贸信息》 2003年第2期56-57,共2页
Article 18. Notices All notices required hereunder shallbe in writing in English language, and shallbe sent by registered mail to the respectiveparties at the following addresses or suchother addresses as the respecti... Article 18. Notices All notices required hereunder shallbe in writing in English language, and shallbe sent by registered mail to the respectiveparties at the following addresses or suchother addresses as the respective partiesmay designate in writing; To Exporter: To Agent; Any notice sent as above shall becomeeffective seven (7) days after posting. 第十八条 通知 本合同有关的必要的通知,应为英语的书面形式。并按照以下地址或相关当事人书面指示的其他地址邮寄给各当事人。出口方地址:代理商地址:按照上述地址投递的任何通知,应在投函后的7天生效。 展开更多
关键词 外商 海外经销合同 代理合同 通知 仲裁 转让 易条件 标题 语言
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The identification of global strategic shipping pivots and their spatial patterns 被引量:7
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作者 王成金 陈沛然 陈云浩 《Journal of Geographical Sciences》 SCIE CSCD 2018年第9期1215-1232,共18页
In concert with developments in global trade and energy resource transportation, there has been a marked increase in reliance on overseas shipping. Unimpeded marine transportation has therefore become a key issue whic... In concert with developments in global trade and energy resource transportation, there has been a marked increase in reliance on overseas shipping. Unimpeded marine transportation has therefore become a key issue which influences national maritime interests including the security of trade and energy resources. A strategic shipping pivot thus performs a vital controlling function for global shipping networks. In this study strategic shipping pivots are defined and subdivided into sea hubs, channels and areas. We then develop a model to identify strategic shipping pivots on a global scale. The results show that, depending on differences in location, function, and type, the concept of strategic shipping pivot permits the identification of both spatial and structural differentiation with respect to strategic hubs, corridors, and seas. Now 44 strategic hubs have formed across the globe. These hubs have become the control centers of local shipping network organization. At the same time, seven strategic corridors containing most shipping routes and transportation capacity connect important sea areas, and permit a high-degree of control over the transport of strategic materials. The strategic seas, the Caribbean, the Mediterranean, Southeast Asia, and the Pacific provide vital import and export pathways, so that the formation of strategic shipping pivots is mainly influenced by factors such as physical geographical conditions, the spatial distribution of socio-economic activities, business organization, technical progress, geopolitical patterns and geopolitical disputes. Physical geographical conditions provide the potential foundations for strategic shipping pivots, while the spatial distribution of socio-economic activities and communications determine the strategic value of these points. Finally, business organization, technical progress, and geopolitical disputes all function to strengthen the strategic mechanisms and the mutagenicity of strategic shipping pivots. 展开更多
关键词 strategic shipping pivot identification model spatial patterns mechanisms of development
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Non-ideal space division multiple access and its application
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作者 Ji-ying XIANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2018年第3期357-366,共10页
We study the performance of space division multiple access (SDMA) under a non-ideal engineering situation. When the SDMA channel is of high inter-layer correlation and the condition number is large, the multiple use... We study the performance of space division multiple access (SDMA) under a non-ideal engineering situation. When the SDMA channel is of high inter-layer correlation and the condition number is large, the multiple user multiple input and multiple output user equipment (MUMIMOUE) grouping should be optimized, and in some cases further dimension-reduction should be applied. As the channel measuring is always non-ideal, we use two methods, feedback mode and non-feedback mode, in terms of performance and overhead. It is proposed that the non-feedback mode is preferable even for some non-reciprocal channels. Prin- ciple analysis and test results are given. 展开更多
关键词 Fifth generation(5G) Condition number Channel reciprocity Feedback mode Non-feedback mode
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