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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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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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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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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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专利出海与中国企业对外直接投资 被引量:1
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作者 曲如晓 王陆舰 杜毓琦 《经济与管理研究》 CSSCI 北大核心 2024年第6期112-130,共19页
专利出海作为开放创新生态的重要内容,是推进高水平对外开放的新优势。本文选取2003—2021年中国专利出海上市企业为研究对象,探究专利出海对中国企业对外直接投资的影响及作用机制。研究结果显示,专利出海能够促进中国企业对外直接投资... 专利出海作为开放创新生态的重要内容,是推进高水平对外开放的新优势。本文选取2003—2021年中国专利出海上市企业为研究对象,探究专利出海对中国企业对外直接投资的影响及作用机制。研究结果显示,专利出海能够促进中国企业对外直接投资,其动态滞后效应在第2期达到最大。在考虑多维专利出海质量、内生性问题和进行一系列稳健性检验后,结论依然成立。机制检验结果表明,专利出海通过技术领先效应和声誉传递效应促进中国企业对外直接投资。异质性分析结果显示,专利出海对数字化企业、顺向投资企业和民营企业对外直接投资的促进作用明显,对中国企业向投资网络社区内东道国、高知识产权保护东道国的投资促进作用更强。本文为依托创新全球化布局推动企业对外投资提供了微观依据,对提升国际循环质量和实现更高水平开放型经济具有重要启示。 展开更多
关键词 专利出海 创新 对外直接投资 企业生产率 企业声誉
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