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QC-LDPC码的普适Kronecker积-逐步边增加算法
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作者 李思佳 毛玉泉 +2 位作者 曹祥玉 裴鑫 尹忠海 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2013年第1期244-249,共6页
为了扩展QC-LDPC码的逐步边增加(Progressive edge-growth,PEG)算法,在分析Kronecker积和PEG基本算法的基础上,结合校验矩阵节点的度分布要求,提出了一种QC-LDPC码的Kronecker积-PEG普适算法。该算法通过引入Kronecker积实现基矩阵的构... 为了扩展QC-LDPC码的逐步边增加(Progressive edge-growth,PEG)算法,在分析Kronecker积和PEG基本算法的基础上,结合校验矩阵节点的度分布要求,提出了一种QC-LDPC码的Kronecker积-PEG普适算法。该算法通过引入Kronecker积实现基矩阵的构造,同时确定循环移位矩阵,进一步根据变量节点和校验节点的度分布要求完成了QC-LDPC码的设计,分析并证明了该算法的环长至少为girth-8。对算法性能进行了仿真验证,结果表明,该算法在保持QC-LDPC码低密度特征和良好误码性能的同时具有普适性。 展开更多
关键词 通信技术 逐步边增加算法 KRoneCKER积 QC-LDPC码 基矩阵 度分布
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Assessment for Production and Operation Ability of Medium and Small-sized Enterprises Based on Neural Network 被引量:3
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作者 WANG Yu-hong XU Jun +1 位作者 WANG Guan ZENG Qi 《Journal of China University of Mining and Technology》 EI 2006年第3期376-380,共5页
In order to improve production and operation ability of medium and small-sized enterprises, an assessment-index system of production and operation ability was proposed, and a corresponding assessment model was establi... In order to improve production and operation ability of medium and small-sized enterprises, an assessment-index system of production and operation ability was proposed, and a corresponding assessment model was established based on BP neural network. The conjunction weights of the neural network were continuously modified from output layer to input layer in the process of neural network training to reduce the errors between the anticipated and actual outputs. The results from an example show that this method is reliable and feasible. The production and operation abilitv of an enterorise with assessed result of 0.833 is fairly oowerful, and that with assessed result of 0.644 is average. 展开更多
关键词 medium and small-sized enterprises production and operation ability BP neural network ASSESSMENT
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Comparison of Production-Triggering Strategies for Manufacturing Enterprises under Random Orders 被引量:1
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作者 Longfei Zhou Lin Zhang Yajun Fang 《Engineering》 SCIE EI 2021年第6期798-806,共9页
Although new technologies have been deeply applied in manufacturing systems,manufacturing enterprises are still encountering difficulties in maintaining efficient and flexible production due to the random arrivals of ... Although new technologies have been deeply applied in manufacturing systems,manufacturing enterprises are still encountering difficulties in maintaining efficient and flexible production due to the random arrivals of diverse customer requirements.Fast order delivery and low inventory cost are fundamentally contradictory to each other.How to make a suitable production-triggering strategy is a critical issue for an enterprise to maintain a high level of competitiveness in a dynamic environment.In this paper,we focus on production-triggering strategies for manufacturing enterprises to satisfy randomly arriving orders and reduce inventory costs.Unified theoretical models and simulation models of different production strategies are proposed,including time-triggered strategies,event-triggered strategies,and hybrid-triggered strategies.In each model,both part-production-triggering strategies and product-assembly-triggering strategies are considered and implemented.The time-triggered models and hybrid-triggered models also consider the impact of the period on system performance.The results show that hybrid-triggered and time-triggered strategies yield faster order delivery and lower inventory costs than event-triggered strategies if the period is set appropriately. 展开更多
关键词 Collaborative manufacturing production triggering OPTIMIZATION Simulation enterprise
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Fuzzy integral based measurement and assessment of medium and small enterprises'product innovation 被引量:1
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作者 毕克新 张铁柱 +1 位作者 孙金花 冯英浚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期278-283,共6页
A fuzzy integral based way of measurement assessment has been established by using linguistic varia-bles and combining fuzzy integral with hierarchy analysis for measurement of medium and small enterprises'product... A fuzzy integral based way of measurement assessment has been established by using linguistic varia-bles and combining fuzzy integral with hierarchy analysis for measurement of medium and small enterprises'product innovation. The conclusions drawn from analyses made with 20 medium and small enterprises providebases for governments to formulate applicable policies and for medium and small enterprises to enhance theirproduct innovation. 展开更多
关键词 medium and small enterprises (MSE) product innovation measurement and assessment fuzzy integral
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From Less or No Waste Manufacturing and Cleaner Production to Recycle Economy -- A Review on the Theoretical Research and Practice of Ecological Enterprises in China 被引量:2
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作者 LiuYong 《Ecological Economy》 2005年第2期32-39,共8页
Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enter- prise... Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enter- prises are developing into a new stage in which governments are launching some pilot projects about construct- ing ecological enterprises. And after that, governments should make policies to spread construction of ecological enterprises, to construct ecological enterprises in legal system and conforming to the standard as soon as possibly. So that, the basic units of ecological economy that fit to the conditions of China will be set up. 展开更多
关键词 ecological enterprises cleaner production recycle economy the system of environment management implements of cleaner production.
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Appraisement on Contributive Ratio of Scientific and Technical Progresses in Milk Productive Enterprises by Model C^2GS^2
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作者 SUN Futian SUN Liqun YANG Guanglin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第4期41-44,共4页
Scientific and technical progress has been the driving forces of enterprises development.Milk productive enterprises are developing faster and growing better.It is very important to measure the contributive ratio of s... Scientific and technical progress has been the driving forces of enterprises development.Milk productive enterprises are developing faster and growing better.It is very important to measure the contributive ratio of scientific and technical progress in milk productive enterprises.And the appraisement could help to develop milk productive enterprises.The model C^2GS^2 was established to appraise the contributive ratio of scientific and technical progress in milk productive enterprises in the research.And the appraisement on the contributive ratio of scientific and technical progress in milk productive enterprises was made by the model.In the results of appraisement,science and technology play a main role in milk productive enterprises.It is shown that our milk productive enterprises are developed by scientific and technical progress while not by input of productive factors. 展开更多
关键词 model C^2GS^2 milk productive enterprises APPRAISEMENT contributive ratio
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HIGH-PERFORMANCE SIMPLE-ENCODING GENERATOR-BASED SYSTEMATIC IRREGULAR LDPC CODES AND RESULTED PRODUCT CODES
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作者 Yang Fengfan Ye Ming Luo Lin 《Journal of Electronics(China)》 2007年第5期613-621,共9页
Low-Density Parity-Check (LDPC) code is one of the most exciting topics among the coding theory community.It is of great importance in both theory and practical communications over noisy channels.The most advantage of... Low-Density Parity-Check (LDPC) code is one of the most exciting topics among the coding theory community.It is of great importance in both theory and practical communications over noisy channels.The most advantage of LDPC codes is their relatively lower decoding complexity compared with turbo codes,while the disadvantage is its higher encoding complexity.In this paper,a new ap- proach is first proposed to construct high performance irregular systematic LDPC codes based on sparse generator matrix,which can significantly reduce the encoding complexity under the same de- coding complexity as that of regular or irregular LDPC codes defined by traditional sparse parity-check matrix.Then,the proposed generator-based systematic irregular LDPC codes are adopted as con- stituent block codes in rows and columns to design a new kind of product codes family,which also can be interpreted as irregular LDPC codes characterized by graph and thus decoded iteratively.Finally, the performance of the generator-based LDPC codes and the resultant product codes is investigated over an Additive White Gaussian Noise (AWGN) and also compared with the conventional LDPC codes under the same conditions of decoding complexity and channel noise. 展开更多
关键词 LDPC code Iterative decoding Parity-check Generator matrix product code GRAPH Kronecker product
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Exogenous Financing,State-Ownership Features and Enterprises Productivity-An Empirical Analysis on Listed Chinese Manufacturing Enterprises
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作者 Xiangqi Zhou Jiawen Qi Haiyue Liu 《Chinese Business Review》 2018年第9期431-441,共11页
This study examines how the exogenous financing and state-ownership features affect the enterprises’productivity by observing the financing data of 1,481 Chinese listed enterprises over the period 2001-2016.The resul... This study examines how the exogenous financing and state-ownership features affect the enterprises’productivity by observing the financing data of 1,481 Chinese listed enterprises over the period 2001-2016.The result shows that long-term loan has a positive impact on enterprises’productivity.Short-term loan and account payable have a negative impact on enterprises’productivity.Also,we find that state-ownership features have a negative impact on enterprises productivity.Moreover,this paper investigates the relationship between enterprises’productivity and the degree of regional economic development measured by GDP on provincial level.The result shows provincial economic development is positively related to the enterprises productivity.These findings are useful for both related authorities and enterprises for better understanding of the financial channels and constrains in China and the possible solutions to more diversified exogenous financing. 展开更多
关键词 EXOGENOUS FINANCING state-ownership FEATURES enterpriseS productIVITY
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Establishment of Person and Enterprise Process Model in Product Data Management System
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作者 Ming-lun Fang Jun-bo Mao Tao Yu 《Advances in Manufacturing》 2000年第3期239-242,共4页
Before the implementation of product data management (PDM) system, person model and enterprise process model (EPM) must be firstly established. For the convenience of project management, all the related users must be ... Before the implementation of product data management (PDM) system, person model and enterprise process model (EPM) must be firstly established. For the convenience of project management, all the related users must be allocated to the “Person User Role Group” net. Based on the person model and the direction of information flow, the EPM is established subsequently. The EPM consists of several release levels, in which the access controls are defined. The EPM procedure shows the blueprint of the workflow process structure. The establishment of person model and EPM in an enterprise has been instanced at the end of this paper. 展开更多
关键词 product data management(PDM) person model enterprise process model
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Design and Implementation of a Novel Algorithm for Iterative Decoding of Product Codes
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作者 李宗旺 Song +2 位作者 Wentao Luo Hanwen 《High Technology Letters》 EI CAS 2003年第1期35-40,共6页
A novel product code iterative decoding algorithm and its high speed implementation scheme are proposed in this paper. Based on partial combination of selected columns of check matrix, the reduced-complexity syndrome ... A novel product code iterative decoding algorithm and its high speed implementation scheme are proposed in this paper. Based on partial combination of selected columns of check matrix, the reduced-complexity syndrome decoding method is proposed to decode sub-codes of product code and deliver soft output information. So iterative decoding of product codes is possible. The fast sorting algorithm and a look-up method are proposed for high speed implementation of this algorithm. Compared to the conventional weighing iterative algorithm, the proposed algorithm has lower complexity while offering better performance, which is demonstrated by simulations and implementation analysis. The implementation scheme and verilog HDL simulation show that it is feasible to achieve high speed decoding with the proposed algorithm. 展开更多
关键词 iterative decoding product codes syndrome decoding FPGA
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Comparison of Online Distribution Channels of the Thailand Community Enterprise Products
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作者 Rataphol Sangkhasuk Kanlaya Naklungka +1 位作者 Wiriyaporn Ekphon Worapun Surasawadee 《Management Studies》 2018年第3期206-211,共6页
This research aims to study an online distribution of community enterprise products,to design the management system for an e-commerce distribution channel,and to compare the efficiency of distribution channels through... This research aims to study an online distribution of community enterprise products,to design the management system for an e-commerce distribution channel,and to compare the efficiency of distribution channels through a developed e-commerce system and ready web.A personal interview survey method was used to collect data on the production,marketing,and online selling issues.In total 150 community enterprise entrepreneurs in five product categories(food,appliance/home decoration,beverage,garment/ornament and non-food herb)and 50 consumers were equally selected by judgment sampling method.The e-commerce channel that was developed is our website and social network website that was selected to compare the efficiency of distribution channels is Facebook.The research found that only 14.67%of community enterprise entrepreneurs sell products through online channel.The product which was sold through the developed website and maximized gross profit is food(35.53%of total revenue).The others,are beverage,non-food herb,appliance/home decoration,and garment/ornament,earn gross profit 31.50%,22.39%,9.78%and 0.80%of total revenue,respectively.The result of distribution channels comparison between our website and webpages on Facebook found that Facebook has the ability to reach customers 2,811 times more than the website 64.75%,which has only 991 times.Regarding to sales,it is found that revenue from Facebook is higher than the website in all product categories. 展开更多
关键词 COMMUNITY enterprise productS E-COMMERCE ONLINE channel
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Lianyungang's Famous Enterprises and Products
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《China's Foreign Trade》 1996年第10期45-46,共2页
Jiangsu Suntory Food Co. Ltd.The company was established by jointinvestment from the China International TrustInvestment Corporation, the Jiangsu ProvincialInternational Trust Investment Corporation,
关键词 OVER Lianyungang’s Famous enterprises and products HIGH GOLD
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Domestic Enterprises Fond of Electronic Product Codedardization
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《China Standardization》 2004年第4期7-7,共1页
关键词 Domestic enterprises Fond of Electronic product codedardization
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A Study on "Internet +" Eco-production and Eco-tourism Mode for Agricultural Enterprises
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作者 Ming LI Jinfa SHEN Deqin LIN 《Asian Agricultural Research》 2017年第8期24-26,33,共4页
"Internet +" eco-production and eco-tourism carried out by agricultural enterprises is one of ways to increase income.Urban economic development index evaluation value(u_1),agricultural enterprises' eco-... "Internet +" eco-production and eco-tourism carried out by agricultural enterprises is one of ways to increase income.Urban economic development index evaluation value(u_1),agricultural enterprises' eco-production and eco-tourism index evaluation value(u_2) and Internet popularity index evaluation value(u_3) constitute the ternary coupling system.The ternary coupling coordination degree(D_3) combined with u_2 can be used to judge whether the agricultural enterprises practise eco-production and eco-tourism mode.When u_2≥ 0.5000,D3≥0.6000,the autonomous mode for agricultural enterprises can be used; when 0.4000≤u_2< 0.5000,0.5000≤D_3< 0.6000,the mode of cooperation with travel agency can be used; when 0.3000 ≤u_2< 0.4000,0.4000 ≤D < 0.5000,the tourism business transfer mode can be used; when u_2< 0.3000,D < 0.4000,the tourism business should not be carried out.All the above four modes require "Internet +". 展开更多
关键词 Agricultural enterprises Eco-production and eco-tourism Internet + Ternary coupling coordination
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Studies on GIS Based Tracing and Traceability of Safe Crop Product in China 被引量:29
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作者 QU Xiao-hui ZHUANG Da-fang QIU Dong-sheng 《Agricultural Sciences in China》 CAS CSCD 2007年第6期724-731,共8页
The safety of safe crop products (SCP) is critical to maintain people's health and living standard. With the global efforts on the improvement of the traceability of food products, it is inevitable to establish cor... The safety of safe crop products (SCP) is critical to maintain people's health and living standard. With the global efforts on the improvement of the traceability of food products, it is inevitable to establish corresponding traceability systems to monitor the safety of crop products in China. In this article, the supply chain pattern of SCP in China has been analyzed and its spatial characters have been described in detail. The study deals with on how to relate traceability technology with GIS, and on how to trace and retrace the safety of SCP using the function of excellent spatial representation, spatial locating, and spatial analysis provided in GIS, which has been discussed from several aspects, such as coding technique of traceability information, transferring technique of traceability information, spatialization of traceability information, and application integration of traceability system. A pilot study was carried out to present the basic functions of the system, which provided an efficient and credible way to trace and retrace the safety of SCP in a real supply chain. An innovative idea has been brought forward for how to establish an efficient, credible, applied traceability system of SCP. 展开更多
关键词 safe crop products (SCP) tracing and traceability GIS traceability code information transformation
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Erasure-Correction-Enhanced Iterative Decoding for LDPC-RS Product Codes 被引量:5
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作者 Weigang Chen Ting Wang +1 位作者 Changcai Han Jinsheng Yang 《China Communications》 SCIE CSCD 2021年第1期49-60,共12页
Low-density parity-check(LDPC)codes are widely used due to their significant errorcorrection capability and linear decoding complexity.However,it is not sufficient for LDPC codes to satisfy the ultra low bit error rat... Low-density parity-check(LDPC)codes are widely used due to their significant errorcorrection capability and linear decoding complexity.However,it is not sufficient for LDPC codes to satisfy the ultra low bit error rate(BER)requirement of next-generation ultra-high-speed communications due to the error floor phenomenon.According to the residual error characteristics of LDPC codes,we consider using the high rate Reed-Solomon(RS)codes as the outer codes to construct LDPC-RS product codes to eliminate the error floor and propose the hybrid error-erasure-correction decoding algorithm for the outer code to exploit erasure-correction capability effectively.Furthermore,the overall performance of product codes is improved using iteration between outer and inner codes.Simulation results validate that BER of the product code with the proposed hybrid algorithm is lower than that of the product code with no erasure correction.Compared with other product codes using LDPC codes,the proposed LDPC-RS product code with the same code rate has much better performance and smaller rate loss attributed to the maximum distance separable(MDS)property and significant erasure-correction capability of RS codes. 展开更多
关键词 low-density parity-check codes product codes iterative decoding Reed-Solomon codes
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Primary logistics planning of oil products under the imbalance of supply and demand 被引量:4
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作者 Rui Qiu Yong-Tu Liang +4 位作者 Qi Liao Ying-Qi Jiao Bo-Hong Wang Yi Guo Hao-Ran Zhang 《Petroleum Science》 SCIE CAS CSCD 2022年第4期1915-1925,共11页
This paper intends to complete the primary logistics planning of oil products under the imbalance of supply and demand. An integrated mathematical programming model is developed to simultaneously find the balance betw... This paper intends to complete the primary logistics planning of oil products under the imbalance of supply and demand. An integrated mathematical programming model is developed to simultaneously find the balance between supply and demand, and optimize the logistics scheme. The model takes minimum logistics cost and resource adjustment cost as the objective function, and takes supply and demand capacity, transportation capacity, mass balance, and resource adjustment rules as constraints.Three adjustment rules are considered in the model, including resource adjustment within oil suppliers,within oil consumers, and between oil consumers. The model is tested on a large-scale primary logistics of a state-owned petroleum enterprise, involving 37 affiliated refineries, 31 procurement departments,286 market depots and dedicated consumers. After the unified optimization, the supply and demand imbalance is eased by 97% and the total cost is saved by 7%, which proves the effectiveness and applicability of the proposed model. 展开更多
关键词 Oil product logistics Supply and demand imbalance Petroleum enterprise Resource adjustment Mathematical Programming model
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Informationization of coal enterprises and digital mine 被引量:3
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作者 卢建军 王晓路 +1 位作者 马莉 赵安新 《Journal of Coal Science & Engineering(China)》 2008年第3期512-516,共5页
Analyzed the main problems which were found in current conditions and prob- lems of informationization in coal enterprises.It clarified how to achieve informationization in coal mine and put forward a general configur... Analyzed the main problems which were found in current conditions and prob- lems of informationization in coal enterprises.It clarified how to achieve informationization in coal mine and put forward a general configuration of informationization construction in which informationization in coal enterprises was divided into two parts: informationization of safety production and informationization of management.Planned a platform of inte- grated management of informationization in coal enterprises.Ultimately,it has brought forward that an overall integrated digital mine is the way to achieve the goal of informa- tionization in coal enterprises,which can promote the application of automation,digitaliza- tion,networking,informaitionization to intellectualization.At the same time,the competi- tiveness of enterprises can be improved entirely,and new type of coal industry can be supported by information technology. 展开更多
关键词 informationization coal enterprises digital mine safety production MANAGEMENT
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A Retrospective Cohort Mortality Study in Jinchang,the Largest Nickel Production Enterprise in China 被引量:4
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作者 MA Li BAI Ya Na +6 位作者 PU Hong Quan HE Jie Bryan A.Bassig DAI Min ZHANG Ya Wei ZHENG Tong Zhang CHENG Ning 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第7期567-571,共5页
Nickel is an essential trace metal used in the occupational setting, resulting in both occupational and nonoccupational exposures to individuals at varying levels. Exposure to nickel has been associated with several t... Nickel is an essential trace metal used in the occupational setting, resulting in both occupational and nonoccupational exposures to individuals at varying levels. Exposure to nickel has been associated with several toxicities and the International Agency for Research on Cancer has concluded that there is sufficient evidence in humans associating exposure to nickel compounds with risk of lung cancer and sinonasal cancer. This study confirmed a significant excess of mortality from diseases of the lung including silicosis, lung cancer, and cor pulmonale among workers involved in nickel mining or smelting in China. 展开更多
关键词 SMR A Retrospective Cohort Mortality Study in Jinchang the Largest Nickel production enterprise in China
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Integrated management system of agro-fishery products based on QR-code 被引量:1
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作者 Namjin Bae Yongyun Cho +1 位作者 Jongsun Choi Jaeyoung Choi 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期252-255,共4页
Recently,both the importance and awareness relating to food safety relating to agrochemicals,chemical fertilizers,the pollution of ecosystem and unwholesome foods are growing rapidly.For the same reason,the purchaser&... Recently,both the importance and awareness relating to food safety relating to agrochemicals,chemical fertilizers,the pollution of ecosystem and unwholesome foods are growing rapidly.For the same reason,the purchaser's curiosity increases to know about the production process which can be accomplished by production traceability system.The traceability system can store and superintend the specific attribute information about products regarding the productive centre,producer and production finish data.The products undergo various circulation processes and they are being managed by individually constructed traceability system.Thus,it is difficult for the producer and the consumer to guarantee the safety from transpirable issues about the falsification of production traceability because the traceability information can be re-produced by forging through various ways.So in this paper,we proposed a system for integrated management of agro-fishery products based on quick response code(QR-code)for forgery prevention which may help to solve these issues.The proposed system makes QR-code using production information provided by producer.And then it is provided to the distributor and the consumer through integrated service model using the QR-code.Therefore,this system make sure to provide the same production traceability about the products to the distributor and the consumer and always keeps both updated with the same information. 展开更多
关键词 quick response code (QR-code production traceability traceability systemCLC number:TP391.44 Document code:AArticle ID:1674-8042(2013)03-0252-04
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