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Distance Compatibility for the Direct Product of Signed Graphs
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作者 Ziqiang FANG Qiannan NIU Haizhen REN 《Journal of Mathematical Research with Applications》 2025年第5期569-580,共12页
A graph whose edges are labeled either as positive or negative is called a signed graph.Hameed et al.introduced signed distance and distance compatibility in 2021,initially to characterize balanced signed graphs which... A graph whose edges are labeled either as positive or negative is called a signed graph.Hameed et al.introduced signed distance and distance compatibility in 2021,initially to characterize balanced signed graphs which have nice spectral properties.This article mainly studies the conjecture proposed by Shijin et al.on the distance compatibility of the direct product of signed graphs,and provides necessary and sufficient conditions for the distance compatibility of the direct product of signed graphs.Some further questions regarding distance compatibility are also posed. 展开更多
关键词 signed graph distance compatibility direct product of signed graphs
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Direct Production of Sorbitol-Plasticized Bioplastic Film from Gracilaria sp.
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作者 Ahmad Faldo Labanta Marbun +6 位作者 Hezekiah Lemuel Putra Zebua Fateha Fateha Rossy Choerun Nissa Yurin Karunia Apsha Albaina Iasya Riri Uswatun Annifah Amrul Amrul Yeyen Nurhamiyah 《Journal of Polymer Materials》 2025年第3期743-755,共13页
Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red ... Conventional bioplastic production from seaweed often relies on extraction processes that are costly,time-consuming,and yield limited product.This study presents a direct fabrication method using Gracilaria sp.,a red seaweed rich in polysaccharides,to produce bioplastic films without the need for extraction.Sorbitol was incorporated as a plasticizer at concentrations of 0%–10%(w/w)to modify film characteristics.Thermal analysis revealed improved stability at moderate sorbitol levels(5%–7%),while excessive plasticizer slightly reduced thermal resistance.Mechanical testing showed that sorbitol increased film flexibility and elongation at break,though tensile strength and stiffness declined.Tear strength followed a non-linear trend,with improvement observed at higher sorbitol concentrations.Seal strength also increased,peaking at 7%,indicating stronger interfacial bonding between film layers.Biodegradation tests demonstrated accelerated decomposition with increased sorbitol content,achieving complete degradation within 30 days at 10% concentration.Color analysis showed increased brightness and reduced yellowing,enhancing the visual quality of the films.These results confirm that direct conversion of bioplastic is both feasible and effective.Sorbitol plays a key role in tuning film properties,offering a low-cost,scalable pathway to biodegradable materials suitable for environmentally friendly packaging applications. 展开更多
关键词 Gracilaria sp. BIODEGRADABILITY direct seaweed production bioplastic film plastic waste alternatives
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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
In the paper [1] the upgrade of the structure of groups has been considered, in which the concept of HX group has been raised. In this paper we will discuss the direct product of HX groups and AX groups on direct prod... In the paper [1] the upgrade of the structure of groups has been considered, in which the concept of HX group has been raised. In this paper we will discuss the direct product of HX groups and AX groups on direct product group. 展开更多
关键词 HX group structure of group direct product
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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 staggered fermion K-cycle direct product finitely generated Abelian group
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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
In this paper we define direct product of graphs and give a recipe for obtaining probability of observing particle on vertices in the continuous-time classical and quantum random walk. In the recipe, the probability o... In this paper we define direct product of graphs and give a recipe for obtaining probability of observing particle on vertices in the continuous-time classical and quantum random walk. In the recipe, the probability of observing particle on direct product of graph is obtained by multiplication of probability on the corresponding to sub-graphs, where this method is useful to determining probability of walk on compficated graphs. Using this method, we calculate the probability of Continuous-time classical and quantum random walks on many of finite direct product Cayley graphs (complete cycle, complete Kn, charter and n-cube). Also, we inquire that the classical state the stationary uniform distribution is reached as t→∞ but for quantum state is not always satisfied. 展开更多
关键词 continuous-time random walk classical random walk quantum random walk direct product of graphs Cayley graphs
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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
A new concept Graded Finite Poset is proposed in this paper. Through discussing some basic properties of it, we come to that the direct product of graded finite posets is connected if and only if every graded finite p... A new concept Graded Finite Poset is proposed in this paper. Through discussing some basic properties of it, we come to that the direct product of graded finite posets is connected if and only if every graded finite poset is connected. The graded function of a graded finite poset is unique if and only if the graded finite poset is connected. 展开更多
关键词 Graded poset graded finite poset graded function direct product connected post
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On total{k}-domatic number of Cartesian and direct product of graphs
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作者 LIANG Yong PEI Lidan +1 位作者 HU Futao HOU Xinmin 《中国科学技术大学学报》 CAS CSCD 北大核心 2018年第8期605-611,共7页
For a positive integer k,the total{k}-dominating function(T{k}DF)of a graph G without isolated vertices is a function f from the vertex set V(G)to the set{0,1,2,…,k}such that for each vertex v∈V(G),the sum of the va... For a positive integer k,the total{k}-dominating function(T{k}DF)of a graph G without isolated vertices is a function f from the vertex set V(G)to the set{0,1,2,…,k}such that for each vertex v∈V(G),the sum of the values of all its neighbors assigned by f is at least k.A set{f_(1),f_(2),…,f_(d)}of pairwise different T{k}DF s of G with the property that∑d i=1 f_(i)(v)≤k for each v∈V(G),is called a total{k}-dominating family(T{k}D family)of G.The total{k}-domatic number of a graph G,denoted by d^({k})_(t)(G),is the maximum number of functions in T{k}D family.In 2013,Aram et al.proposed a problem that whether or not d^({k})_(t)(C_(m)□C_(n))=3 when 4 nmk,and d^({k})_(t)(C m□C n)=4 when 4|nmk.It was shown that d^({k})_(t)(C_(m)□C_(n))=3 if 4 nmk and k≥2 or 4|nmk and 2 nk,which partially answered the above problem.In addition,the total{k}-domatic number of the direct product of a cycle and a path,two paths,and two cycles was studied,respectively. 展开更多
关键词 total{k}-domatic number Cartesian product direct product
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Fixed Subgroups are not Compressed in Direct Products of Surface Groups
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作者 Qiang ZHANG Jianchun WU Fanling GU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2024年第5期703-708,共6页
By constructing counterexamples,the authors show that the fixed subgroups are not compressed in direct products of free and surface groups,and hence negate a conjecture in[Zhang,Q.,Ventura,E.and J.Wu,Fixed subgroups a... By constructing counterexamples,the authors show that the fixed subgroups are not compressed in direct products of free and surface groups,and hence negate a conjecture in[Zhang,Q.,Ventura,E.and J.Wu,Fixed subgroups are compressed in surface groups,Internat.J.Algebra Comput.,25,2015,865–887]. 展开更多
关键词 Fixed subgroup Free group Surface group direct product INERTIA Compression
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Weak type(1, 1) of the Riesz transform on some direct product manifolds with exponential volume growth
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作者 Hong-Quan Li Jie-Xiang Zhu 《Science China Mathematics》 SCIE CSCD 2024年第7期1599-1622,共24页
In this paper, we are concerned with the Riesz transform on the direct product manifold H^(n)× M,where H^(n) is the n-dimensional real hyperbolic space, and M is a connected complete non-compact Riemannian manifo... In this paper, we are concerned with the Riesz transform on the direct product manifold H^(n)× M,where H^(n) is the n-dimensional real hyperbolic space, and M is a connected complete non-compact Riemannian manifold satisfying the volume doubling property and generalized Gaussian or sub-Gaussian upper estimates for the heat kernel. We establish its weak type(1, 1) property. In addition, we obtain the weak type(1, 1) of the heat maximal operator in the same setting. Our arguments also work for a large class of direct product manifolds with exponential volume growth. Particularly, we provide a simpler proof of weak type(1, 1) boundedness of some operators considered in the work of Li et al.(2016). 展开更多
关键词 Riesz transform heat kernel direct product real hyperbolic space
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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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The Twin Domination Number of Cartesian Product of Directed Cycles 被引量:1
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作者 Hongxia MA Juan LIU 《Journal of Mathematical Research with Applications》 CSCD 2016年第2期171-176,共6页
Let γ*(D) denote the twin domination number of digraph D and let Cm Cn denote the Cartesian product of C_m and C_n, the directed cycles of length m, n ≥ 2. In this paper, we determine the exact values: γ*(C_2... Let γ*(D) denote the twin domination number of digraph D and let Cm Cn denote the Cartesian product of C_m and C_n, the directed cycles of length m, n ≥ 2. In this paper, we determine the exact values: γ*(C_2□C_n) = n; γ*(C_3 □C_n) = n if n ≡ 0(mod 3),otherwise, γ*(C_3□C_n) = n + 1; γ*(C_4□C_n) = n + n/2 if n ≡ 0, 3, 5(mod 8), otherwise,γ*(C_4□C_n) = n + n/2 + 1; γ*(C_5□C_n) = 2n; γ*(C_6□C_n) = 2n if n ≡ 0(mod 3), otherwise,γ*(C_6□C_n) = 2n + 2. 展开更多
关键词 twin domination number Cartesian product directed cycles
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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:6
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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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Hydrogen Production Using ‘‘Direct-Starting” Biocathode Microbial Electrolysis Cell and the Analysis of Microbial Communities 被引量:1
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作者 Hong-Yan Dai Hui-Min Yang +2 位作者 Xian Liu Xiu-Li Song Zhen-Hai Liang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2019年第3期297-304,共8页
In this study, a ‘‘direct-starting'' procedure was used to activate a single-chamber biocathode microbial electrolysis cell(MEC) and the development of a biocathode was studied through output current curves ... In this study, a ‘‘direct-starting'' procedure was used to activate a single-chamber biocathode microbial electrolysis cell(MEC) and the development of a biocathode was studied through output current curves and cyclic voltammograms. It only took 163 h for a successful start-up, and a current density of 14.75 A/m^2 was obtained. In the formal hydrogen-production stage, it was found that the biocathode MEC was comparable with the Pt/C cathode MEC in terms of current density and energy efficiency, and the hydrogen recovery, cathodic hydrogen recovery, and hydrogen production rate of the biocathode MEC were 71.22% ± 8.98%, 79.42% ± 5.94%, and 0.428 ± 0.054 m^3 H_2/m^3 days, respectively, which were slightly higher than those obtained with the Pt/C cathode MEC. Besides, under the effect of applied voltage, the microbial populations in the anodophilic biofilm of MEC(MECan) and the cathodophilic biofilm of MEC(MECca) were less diverse than those of the original aerobic activated sludge(AAS) and the anodophilic biofilm of MEC(MECan). Furthermore, the microbial community structures evidently differed between MECan/MECca and AAS/MFC. 展开更多
关键词 direct-starting” PROCEDURE BIOCATHODE Hydrogen production MICROBIAL COMMUNITY structures
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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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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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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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