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On Direct Product of HX Groups 被引量:3
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作者 米洪海 曾文艺 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期1-5, ,共5页
OnDirectProductofHXGroupsMiHonghai(DepartmentofMathematicsandPhysics,HebeiUniversityofTechnology)ZengWenyi(D... OnDirectProductofHXGroupsMiHonghai(DepartmentofMathematicsandPhysics,HebeiUniversityofTechnology)ZengWenyi(DepartmentofMathem... 展开更多
关键词 HX群 直积 结构
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Geometric Origin of Staggered Fermion:Direct Product K—Cycle
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作者 DAIJian XIONGChuang-Sheng SONGXing-Chang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期519-520,共2页
Staggered formalism of lattice fermion can be cast into a form of direct product K-cycle in noncommutative geometry. We prove the correspondence between this staggered K-cycle and a canonically defined K-cycle for fin... Staggered formalism of lattice fermion can be cast into a form of direct product K-cycle in noncommutative geometry. We prove the correspondence between this staggered K-cycle and a canonically defined K-cycle for finitely generated Abelian groups where a lattice appears as a special case. 展开更多
关键词 交错费米子 K循环 粒子物理学 Abelian群 阿贝尔群 直接产物
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Continuous-Time Classical and Quantum Random Walk on Direct Product of Cayley Graphs
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作者 S. Salimi M.A. Jafarizadeh 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期1003-1009,共7页
在这篇论文,我们定义图的直接产品并且为获得在顶点上观察粒子在的概率给一个配方连续时间古典并且量随机散步。在配方,在图的直接产品上观察粒子的概率被概率的增加获得在上相应于亚图,在这个方法对在复杂的图上决定散步的概率有用... 在这篇论文,我们定义图的直接产品并且为获得在顶点上观察粒子在的概率给一个配方连续时间古典并且量随机散步。在配方,在图的直接产品上观察粒子的概率被概率的增加获得在上相应于亚图,在这个方法对在复杂的图上决定散步的概率有用的地方。用这个方法,我们计算概率连续时间古典并且有限直接产品 Cayley 图的许多上的量随机散步(完全的周期,完全的 K <SUB > n </SUB>, 宪章和 n 立方体) 。另外,我们询问古典状态静止一致分发作为 t &#8594; 被到达&#8734; 要不是量,状态总是没满足。 展开更多
关键词 CAYLEY图 随机游动 连续时间 量子态 产物 均匀分布 概率 立方体
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The Direct Product of Graded Finite Posets
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作者 LIU Wei CHEN Shu-wei JIANG Bao-qing 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期430-436,共7页
一个新概念分级有限 Poset 在讨论它的一些基本性质的这 paper.Through 被建议,我们来到如果如果并且仅当分级的有限 poset 被连接,分级的有限 poset 的功能是唯一的并且仅当每分级的有限 poset 是分级的 connected.The ,分级的有限 ... 一个新概念分级有限 Poset 在讨论它的一些基本性质的这 paper.Through 被建议,我们来到如果如果并且仅当分级的有限 poset 被连接,分级的有限 poset 的功能是唯一的并且仅当每分级的有限 poset 是分级的 connected.The ,分级的有限 posets 的直接产品被连接。 展开更多
关键词 分层有限偏序集 直积 数学 抽象代数
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Direct farm, production base, traceability and food safety in China 被引量:4
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作者 DING Ji-ping HUANG Ji-kun +3 位作者 JIA Xiang-ping BAI Jun-fei Steve Boucher Michael Carter 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第11期2380-2390,共11页
With the rapid growth of China's economy, rising demand for safety food has been accompanied by frequent food safety scandals. Given that China's farming is dominated by millions of small-scale farms, ensuring food ... With the rapid growth of China's economy, rising demand for safety food has been accompanied by frequent food safety scandals. Given that China's farming is dominated by millions of small-scale farms, ensuring food safety is a major challenge facing the public and private sectors. The direct farm (DF) program, initiated in 2008, represents one of the government's major initiatives to modernize the distribution of fresh fruit and vegetables (FFV) and improve food safety. Under the DF program, participating national and international retailers are expected to establish more direct procurement relationships with farm communities. While it is often claimed that greater participation by retailers in the production and post-harvest processing implied the DF program will lead to improved quality, safety and traceability, systematic evidence remains elu- sive as existing studies are largely narrative, based on case studies, or theoretical inference. Little empirical evidence is available for a broader evaluation of the DF program. This paper aims to fill this gap by assessing the overall performance of a single retailer's DF experience with respect to the procurement and food safety of FFV. We use data from a survey of production managers of 35 DF production bases (PBs) spread across 11 provinces, 3 cities and 1 autonomous region in China. The results show a mixture of opportunities and challenges. On one hand, the DF program improves production practices and distribution channels of FFV produced on its PBs, thus facilitating the move of China's food system towards improved food safety compliance. On the other hand, significant heterogeneity in the traceability of food and the ability of DF to meet higher safety standards is evident both across major product categories and across household-operated vs. firm-operated PBs. The paper concludes with policy implications. 展开更多
关键词 direct farm production base marketing chain TRACEABILITY food safety
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DIRECT PRODUCT DECOMPOSITION OF MOLECULAR LATTICES AND STRUCTURE OF GENERALIZED ORDER HOMOMORPHISMS 被引量:1
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作者 樊磊 崔宏斌 郑崇友 《Chinese Science Bulletin》 SCIE EI CAS 1989年第7期538-539,共2页
In this note, we shall give the direct product decomposition of a molecular lattice using the concepts of molecules, then we shall discuss the structure of a generalized order homomorphism. About the concepts and nota... In this note, we shall give the direct product decomposition of a molecular lattice using the concepts of molecules, then we shall discuss the structure of a generalized order homomorphism. About the concepts and notations in this note, refer to [1—7]. L(M) denotes a molecular lattice (i. e. a completely distributive lattice) with M as the set of molecules in L. Let {L_i:i∈I} be a family of mo- 展开更多
关键词 MOLECULE molecular LATTICE direct product DECOMPOSITION principal SUBLATTICE GENERALIZED order homomorphism.
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Inner-product of strain rate vector through direction cosine in coordinates for disk forging 被引量:1
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作者 赵德文 金文忠 +1 位作者 王磊 刘相华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2006年第6期1320-1324,共5页
A new linear integration for plastic power was proposed.The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector,and then its direction cosines were determined... A new linear integration for plastic power was proposed.The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector,and then its direction cosines were determined by the ratio of coordinate increments.Furthermore,inner-product of the vector for plastic power was term integrated by term and summed.Thereafter,through a formula for determination of bulge an analytical solution of stress effective factor was obtained.Finally,through compression tests,the calculated results of above formula were compared with those of Avitzur’s approximate solution and total indicator readings of the testing machine.It is indicated that the calculated compression forces are basically in agreement with the measured ones if the pass reduction is less than 13.35%.However,when the reduction gets up to 25.34% and 33.12%,the corresponding errors between the calculated and measured results also get up to 6% and 13.5%,respectively. 展开更多
关键词 DISK FORGING bulge strain rate VECTOR direction COSINE inner-product analytical solution
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Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying 被引量:5
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作者 Hafeez Ur REHMAN Muhammad KAMRAN +2 位作者 Shahzad Maqsood Ahmed BASRA Irfan AFZAL Muhammad FAROOQ 《Rice science》 SCIE CSCD 2015年第4期189-196,共8页
Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated t... Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying (DSR-AWD) in comparison with direct seeded rice at field capacity (DSR- FC). Seed priming treatments were osmo-priming with KCI (2.2%), CaCI2 (2.2%) and moringa leaf extracts (MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation. 展开更多
关键词 crop establishment grain filling rate seed priming water productivity YIELD direct seededrice alternating wetting and drying grain quality
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Analysis of the System of Direct Subsidy for Grain Production in China
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作者 SUN Shun-qiang ZHU Gui-ying ZHANG Tao-mei 《Asian Agricultural Research》 2012年第2期5-8,共4页
This paper introduces the status quo of the system structure of direct subsidy for grain production in China,and analyses the function and essence of direct subsidy for grain production in China as follows:the functio... This paper introduces the status quo of the system structure of direct subsidy for grain production in China,and analyses the function and essence of direct subsidy for grain production in China as follows:the function of direct subsidy for grain production in China is to protect and promote the development of food industry,ensure food supply and national food security,protect grain growers' interests,and maintain the dominant position of national food trade;the essence of direct subsidy for grain production is the compensation for grain producers' reasonable interests,the compensation for positive externality of grain production,and social costs of adjusting equilibrium between food supply and demand.We discuss the problems existing in the system of direct subsidy for grain production in China and put forward corresponding countermeasures as follows:first,adhere to improving synergetic system of direct subsidy for grain production;second,adjust the direct subsidy method of grain production;third,establish long-term mechanism of subsidy for grain production;fourth,promote the information-based service level of the system of direct subsidy for grain production. 展开更多
关键词 direct subsidy for grain production Grain production safety Agricultural fiscal policy
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Efficiency Evaluation of Effect of Direct Grain Subsidy Policy on Performance of Rice Production 被引量:1
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作者 Liyun LU Guanqiao LI 《Asian Agricultural Research》 2017年第4期11-15,共5页
Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain sub... Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production. 展开更多
关键词 direct grain subsidy Rice production performance Scale efficiency Pure technology efficiency DEA
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Inspiration of Direct Grain Production Subsidy System in Typical Countries and Regions
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作者 Shunqiang SUN Lu CHEN Ya LI 《Asian Agricultural Research》 2014年第3期6-10,共5页
Through comparison of direct grain production subsidy system in typical countries and regions,such as the United States,EU,Japan and South Korea,this paper evaluated the performance of direct grain production subsidy ... Through comparison of direct grain production subsidy system in typical countries and regions,such as the United States,EU,Japan and South Korea,this paper evaluated the performance of direct grain production subsidy system. On the basis of comparison and analysis,it summed up experience of the direct grain production subsidy system in typical countries and regions. Finally,it came up with countermeasures and recommendations for improving the direct grain production subsidy system in China. 展开更多
关键词 Grain production direct SUBSIDY Countermeasures an
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DIRECTION OF DEVELOPMENT FORNATION'S PETROCHEMICAL PRODUCTS AND TECHNOLOGY
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《China Oil & Gas》 CAS 2001年第1期36-38,共3页
关键词 DOWN directION OF DEVELOPMENT FORNATION’S PETROCHEMICAL productS AND TECHNOLOGY THAN OVER
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Analysis on After-effects of Direct Subsidies for Grain Production in China
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作者 Shunqiang SUN Huixia GENG Ya LI 《Asian Agricultural Research》 2013年第12期30-32,35,共4页
Long term of grain production subsidy policy can be guaranteed only with sound and sustainable development of economy,stable growth of fiscal revenues,and improvement of subsidy system.In combination with social surve... Long term of grain production subsidy policy can be guaranteed only with sound and sustainable development of economy,stable growth of fiscal revenues,and improvement of subsidy system.In combination with social survey,this paper analyzed after-effects of direct subsidies for grain production in China from pressure of grain production subsidies on central finance and local finance,consequence possibly brought about by classified bearing of direct subsidies for grain production,effectiveness of direct subsidies on stimulating grain production,and effect of direct subsidies on production of other agricultural products.It is concluded that direct subsidies for grain production should be shifted to direct subsides for agricultural production,which will be the reform and development trend of financial support for agriculture. 展开更多
关键词 FISCAL POLICIES direct subsides for GRAIN producti
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On the Signed Domination Number of the Cartesian Product of Two Directed Cycles
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作者 Ramy Shaheen 《Open Journal of Discrete Mathematics》 2015年第3期54-64,共11页
Let D be a finite simple directed graph with vertex set V(D) and arc set A(D). A function ?is called a signed dominating function (SDF) if ?for each vertex . The weight ?of f is defined by . The signed domination numb... Let D be a finite simple directed graph with vertex set V(D) and arc set A(D). A function ?is called a signed dominating function (SDF) if ?for each vertex . The weight ?of f is defined by . The signed domination number of a digraph D is . Let Cm × Cn denotes the cartesian product of directed cycles of length m and n. In this paper, we determine the exact values of gs(Cm × Cn) for m = 8, 9, 10 and arbitrary n. Also, we give the exact value of gs(Cm × Cn) when m, ?(mod 3) and bounds for otherwise. 展开更多
关键词 directed GRAPH directed CYCLE CARTESIAN product SIGNED Dominating Function SIGNED DOMINATION NUMBER
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Analysis of Theoretical Basis of Direct Subsidies for Grain Production
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作者 Shengping SHI Xiaorong LUO Hongjing LI 《Asian Agricultural Research》 2014年第1期24-26,共3页
Financial distribution to compensate grain production reflects governmental macro-control on grain production and supply. With the reference of agricultural basic theory,agricultural multi-function theory,economic ext... Financial distribution to compensate grain production reflects governmental macro-control on grain production and supply. With the reference of agricultural basic theory,agricultural multi-function theory,economic externality theory,public finance and other theories,this article points out that direct subsidies for grain production is reasonable and necessary with six main theoretical basis,namely fundamentality,multi-function,positive externality of grain production,particularity of grain supply and demand,grain safety being closely linked with national security and basic function of service-oriented government. 展开更多
关键词 direct SUBSIDIES for GRAIN productION THEORETICAL
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Properties and Stability of Max-Product Fuzzy Bi-Directional Associative Memory 被引量:2
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作者 舒兰 《Journal of Electronic Science and Technology of China》 2005年第2期175-177,共3页
In this paper, a fuzzy operator of max-product is defined at first, and the fuzzy bi-directional associative memory (FBAM) based on the fuzzy operator of max-product is given. Then the properties and the Lyapunov stab... In this paper, a fuzzy operator of max-product is defined at first, and the fuzzy bi-directional associative memory (FBAM) based on the fuzzy operator of max-product is given. Then the properties and the Lyapunov stability of equilibriums of the networks are studied. 展开更多
关键词 fuzzy operator of max-product max-product fuzzy bi-directional associative memory fuzzy Hebb code EQUILIBRIUM Lyapunov stability
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Direct Marketing and Consumer Trust in Organic Food Products: Vilnius (Lithuania) Case
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作者 Virgilijus Skulskis Vilija Girgzdiene 《Journal of Agricultural Science and Technology(B)》 2013年第4期272-283,共12页
关键词 有机食品 营销渠道 消费者 立陶宛 信任 有机产品 案例 质量控制
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On the Product of Integro Differential Equations and Their Solutions in Direct Sum Spaces
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作者 Sobhy El-sayed Ibrahim 《Journal of Mathematics and System Science》 2013年第5期231-245,共15页
关键词 积分微分方程 直和空间 产品 时间间隔 表达式 系数和 LZW 有界
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The impact of environmental constraint on China's industrial productivity growth:An empirical study based on an directional environmental production model
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作者 涂正革 肖耿 《China Economist》 2010年第2期84-95,共12页
Using input, output and pollution data of industrial enterprises in 30 Chinese provinces and municipalities from 1998 to 2005, this paper creates an environmental production frontier function model to assess China'... Using input, output and pollution data of industrial enterprises in 30 Chinese provinces and municipalities from 1998 to 2005, this paper creates an environmental production frontier function model to assess China's industrial growth sources, particularly environmental control and changes in the industrial environmental structure's impact on industrial productivity. It found that (1) at its current stage, China's rapid industrial growth is accompanied by a slow increase in pollution; (2) environmental total factor productivity has become a primary driver of rapid growth with less pollution; (3) environmental control didn't cause any substantial restraint on China's industrial growth; (4) improvement in industrial environmental structure contributes an increasingly large share to economic growth with less pollution. China's industrial productivity is increasing, its growth model is being transformed, and the environment is exerting a diminishing constraint on economic growth. 展开更多
关键词 ENVIRONMENTAL TOTAL factor productIVITY directional ENVIRONMENTAL production function INDUSTRIAL ENVIRONMENTAL structure
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Effect of irrigation regime on grain yield,water productivity,and methane emissions in dry direct-seeded rice grown in raised beds with wheat straw incorporation 被引量:7
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作者 Zhiqin Wang Daojian Gu +4 位作者 Sarah S.Beebout Hao Zhang Lijun Liu Jianchang Yang Jianhua Zhang 《The Crop Journal》 SCIE CAS CSCD 2018年第5期495-508,共14页
Dry direct-seeded rice grown in raised beds is becoming an important practice in the wheat–rice rotation system in China.However,little information has been available on the effect of various irrigation regimes on gr... Dry direct-seeded rice grown in raised beds is becoming an important practice in the wheat–rice rotation system in China.However,little information has been available on the effect of various irrigation regimes on grain yield,water productivity(WP),nitrogen use efficiency(NUE),and greenhouse gas emission in this practice.This study investigated the question using two rice cultivars in 2015 and 2016 grown in soil with wheat straw incorporated into it.Rice seeds were directly seeded into raised beds,which were maintained under aerobic conditions during the early seedling period.Three irrigation regimes:continuous flooding(CF),alternate wetting and drying(AWD),and furrow irrigation(FI),were applied from 4.5-leaf-stage to maturity.Compared with CF,both AWD and FI significantly increased grain yield,WP,and internal NUE,with greater increases under the FI regime.The two cultivars showed the same tendency in both years.Both AWD and FI markedly increased soil redox potential,root and shoot biomass,root oxidation activity,leaf photosynthetic NUE,and harvest index and markedly decreased global warming potential,owing to substantial reduction in seasonalThe results demonstrate that adoption of either AWD or FI could increase grain yield and resource-use efficiency and reduce environmental risks in dry direct-seeded rice grown on raised beds with wheat straw incorporation in the wheat–rice rotation system. 展开更多
关键词 NITROGEN use efficiency(NUE) continuous flooding(CF)
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