Stackelberg Game-Based Resource Allocation with Blockchain for Cold-Chain Logistics System

Cold-chain logistics system(CCLS)plays the role of collecting and managing the logistics data of frozen food.However,there always exist problems of information loss,data tampering,and privacy leakage in traditional centralized systems,which influence frozen food security and people’s health.The centralized management form impedes the development of the cold-chain logistics industry and weakens logistics data availability.This paper first introduces a distributed CCLS based on blockchain technology to solve the centralized management problem.This system aggregates the production base,storage,transport,detection,processing,and consumer to form a cold-chain logistics union.The blockchain ledger guarantees that the logistics data cannot be tampered with and establishes a traceability mechanism for food safety incidents.Meanwhile,to improve the value of logistics data,a Stackelberg game-based resource allocation model has been proposed between the logistics data resource provider and the consumer.The competition between resource price and volume balances the resource supplement and consumption.This model can help to achieve an optimal resource price when the Stackelberg game obtains Nash equilibrium.The two participants also can maximize their revenues with the optimal resource price and volume by utilizing the backward induction method.Then,the performance evaluations of transaction throughput and latency show that the proposed distributed CCLS is more secure and stable.The simulations about the variation trend of data price and amount,optimal benefits,and total benefits comparison of different forms show that the resource allocation model is more efficient and practical.Moreover,the blockchain-based CCLS and Stackelberg game-based resource allocation model also can promote the value of logistic data and improve social benefits.

Quantum Secure Undeniable Signature for Blockchain-Enabled Cold-Chain Logistics System

Data security and user privacy are two main security concerns in the cold-chain logistics system(CCLS).Many security issues exist in traditional CCLS,destroying data security and user privacy.The digital signature can provide data verification and identity authentication based on the mathematical difficulty problem for logistics data sharing in CCLS.This paper first established a blockchain-enabled cold-chain logistics system(BCCLS)based on union blockchain technology,which can provide secure data sharing among different logistics nodes and guarantee logistics data security with the untampered blockchain ledger.Meanwhile,a lattice-based undeniable signature scheme is designed to strengthen the security of logistics data and user privacy against quantum attacks.This scheme is based on the lattice assumption,which can provide anti-quantum security for BCCLS in the future quantum computer age.It also establishes the undeniable mechanism that guarantees that the actual signer cannot deny a valid signature.Then,security proof shows that this undeniable signature scheme is correct and safe,and an efficiency comparison shows that it is more efficient than other schemes in similar literature.The performance evaluations of transaction throughput and latency show that the proposed BCCLS is efficient and practical.This work can improve the security and efficiency of logistics data management and promote the reform and development of the logistics industry.

Optimization Model of Cold-Chain Logistics Network for Fresh Agricultural Products —Taking Guangdong Province as an Example

Cold-chain demand of fresh agricultural products is increasing in China, while network layout of cold-chain logistics is in disorder and its cost is huge. To address this problem, this paper casts an optimal model of cold-chain logistics network and tackles it with genetic algorithms. This optimal model takes running total cost of logistics network as the objective, and embeds a nonlinear mixed integer programming including two assignment issues. The model determines optimal layout and logistics management for pre-cooling stations and logistics center for fresh agricultural products. Our main contribution is to consider construction cost and operation cost of cold chain logistics simultaneously. Case study illustrates the effectiveness of the model.

The Construction of Cold-Chain Logistics Park of Agricultural Products in Sanshui from Two-stage Perspective

This paper firstly analyzed the operation model,market positioning,market demand forecast as well as market competition and challenges,park site selection,and transportation conditions for construction of the Cold-Chain Logistics Park of Agricultural Products in Sanshui.Then,it presented the overall planning scheme for construction of the Cold-Chain Logistics Park of Agricultural Products from a progressive two-stage perspective of overall planning and stage-by-stage implementation.The first stage mainly performs the function as a transaction platform of agricultural products and meanwhile provides customers with agricultural products storage and inspection services.The second stage adds value-added services such as distribution processing,modified atmosphere storage,freezing and refrigeration,market price information distribution,E-commerce of agricultural products and personalized services.It is expected to provide references and suggestions for the construction of the Cold-Chain Logistics Park of Agricultural Products.

Research on the Challenges of Cold-chain Logistics and the Combination Ways with Logistics O2O Operation

In this paper, we conduct research on challenges of cold-chain logistics and combination ways with logistics O2O operation. Because of the cold chain logistics to the high requirement of the equipment, technology as caused the high cost of cold chain logistics. In the overall cost of China’s logistics is on the high side, under the condition of low profi t, many enterprises to enter and don’t have much interest in the field of cold chain logistics. So-called cold chain logistics is frozen food in the production, storage, transportation, sales, remain the regulations to the consumption of each link in the cold chain environment, to ensure the food quality, reduce loss of food and system engineering. Under this basis, we propose the O2O based logistics pattern that will solve the issues well.

Temporal-spatial Distribution Model of Cold Chain Logistics for Vegetables

[Objective] The aim was to study on temporal-spatial distribution model of cold chain logistics for vegetables. [Method] Broccoli was taken as an example. Detailedly, time-space distribution model of cold chain logistics for broccoli was proposed from standpoints of costs and benefits based on changes of time and space, and a comprehensive evaluation was made on timeliness, efficiency, risks, added- value of products and satisfaction of information in cold-chain logistics. [Result] The efficiency of cold chain logistics for vegetable can be greatly improved by temporal- spatial distribution model of cold chain logistics. [Conclusion] Costs and benefits of vegetables in temporal-apstial distribution could be evaluated by the model.

An Analysis of the Cold Chain Logistics concerning Agricultural Products in Chongqing City

Agriculture is the foundation of the national economy. On the one hand,there is increasing demand for fresh and safe refrigerated agricultural products; on the other hand,the current cold chain logistics is relatively underdeveloped and has many problems. This paper does a research on the major large-scale agricultural cold-chain logistics companies in Chongqing,and finds that cold-chain logistics in Chongqing has some problems such as incomplete industrial chain,relatively backward infrastructure,lack of talents,and high logistics costs. Some solutions to these problems are put forward: improving chain logistics infrastructure; strengthening personnel training; building information platform to create a new model of the cold-chain logistics in the Internet era; seeking government's policy and financial support.

Apple Pay移动支付方式发展影响因素研究

近几年,移动支付应用技术的飞速发展,移动支付用户规模逐年增加,我国的移动支付有着巨大的发展前景。随着美国苹果公司Apple Pay移动支付方式的出现,对我国的移动支付市场也带来了一定的冲击,加剧了移动支付市场的竞争。本文从Apple Pay移动支付方式入手,调查了目前移动支付方式的使用情况,进而对继续使用Apple Pay移动支付方式的影响因素进行了分析和研究,给移动支付方式相关的企业及有意推广Apple Pay移动支付方式的商家提供参考依据。

基于GO-FLOW法的苹果冷链物流系统安全性评价

应用系统可靠性理论,利用GO-FLOW方法对苹果冷链物流系统进行安全性分析和风险评价,进行GO-FLOW程序运算,分析系统各环节的可靠性和故障率,找出了影响系统安全性的关键环节并提出了解决思路.

基于二元逻辑回归分析的苹果汁鉴伪模型(英文)

为了研究苹果汁中有机酸与掺假苹果汁的关系,从而通过检测有机酸进行质量控制和食品安全监督。该文共收集了340个中国产苹果样本并制成苹果汁,涉及14个试点种植区域的19个品种。通过高效液相色谱测定样本中有机酸的种类和含量。该试验通过添加水、L-苹果酸和蔗糖模拟制作原果汁含量分别为57%,50%和25%的掺假苹果汁。在测得的包括原果汁和掺假果汁的有机酸种类和含量的基础上利用二元逻辑回归分析方法建立了判别模型,用以区别掺假苹果汁,模型的精确度和重现率分别为87.4%和94.51%。统计数据显示该模型判别效果良好,可用于苹果汁的质量控制。研究结果证实苹果汁中特征有机酸指纹图谱可以用来鉴别苹果汁掺假。

苹果褐斑病在山东半岛中部的周年流行动态

【目的】褐斑病是中国苹果叶部的重要病害,主要导致苹果树早期大量落叶。研究旨在明确褐斑病的周年发生动态,确定病害的关键防治时期,为病害的流行预测和防控提供参考。【方法】2009和2010年3—7月份,每隔15 d自山东莱阳和青岛两地的苹果园内定期采集落地病叶,随机挑取病叶正面的子实体,镜检已形成拟分生孢子和子囊孢子的子实体,依据拟分生孢子盘和子囊盘在子实体中所占百分率,分析越冬病菌的发育动态。2008—2010年6—10月份,在山东莱阳和青岛的果园内,每隔15 d定树定枝系统调查同一批枝条上所有叶片的发病率和落叶率,将系统调查数据拟合逻辑斯蒂模型,获得能描述褐斑病发病动态的模型参数。2010和2012年9—11月份,每隔10 d从苹果树上随机摘取具有典型症状的苹果褐斑病叶,切取分生孢子盘,镜检分生孢子盘上小型孢子和分生孢子各占的比率,根据小型孢子在分生孢子盘上所占的相对比率的变化,分析褐斑病菌的发育动态。【结果】苹果褐斑病菌在越冬病叶上能产生拟分生孢子和子囊孢子两种类型的孢子。拟分生孢子于3月初至6月底形成,高峰期出现在5月中旬。自苹果树萌芽期开始,拟分生孢子就可以随雨水溅散传播,侵染树体下部叶片。拟分生孢子侵染的叶片,大部分于6月底之前脱落,对褐斑病后期流行作用不大。子囊孢子于5月中旬至6月底成熟,可以随气流传播侵染树体上部叶片,是导致苹果褐斑病后期流行的主要初侵染菌源。子囊孢子侵染的叶片自7月上中旬开始发病,初侵染形成的病叶率低于2%。7月份,初侵染病斑大量产孢,并进行再侵染,病原菌不断积累,7月底病叶率可增长至5%左右。8月份,初侵染病斑和再侵染病斑大量发病,并产孢侵染,导致病叶率迅速增加。8月下旬褐斑病发病达高峰期,12 d后形成落叶高峰。6—9月份苹果褐斑病的累积病叶率和累积落叶率随时间的变化动态可用逻辑斯蒂模型描述。进入9月份,褐斑病菌开始产生小型孢子(性孢子),小型孢子在分生孢子盘上所占比率呈直线增长。10月份褐斑病菌逐渐停止产生分生孢子,进入越冬预备期。【结论】苹果褐斑病在山东半岛中部的周年流行动态可划分为4个阶段:自苹果萌芽至6月底为褐斑病菌的初侵染期。其中5月下旬到6月底是子囊孢子的初侵染期,也是全年防治褐斑病的第1个关键时期。7月份为褐斑病的指数增长期,也是全年防治褐斑病的第2个关键时期。8—9月份是褐斑病的逻辑斯蒂增长期,也是褐斑病的盛发期。10月份褐斑病菌进入越冬预备期。

基于球体模型的苹果接触点局部处理方式研究

为实现新鲜果蔬采后预冷CFD数值模拟研究,以单个富士苹果为研究对象,构建果品近真实3D模型,在雷诺数为10~30 000的范围内对比真实果形与等直径球体壁面切应力、壁面阻力系数、边界层分离角度以及尾流回流区长度之间的不同,验证在CFD模拟研究中是否可直接利用等直径球体替代苹果真实形状。为实现果品与果品（或箱体壁面）接触点局部位置的最佳CFD建模,充分考虑果品之间局部传热性对温度变化的影响,本文以彼此接触的两果模型为研究对象,从壁面阻力系数、两果中心线上的温度模拟结果准确性角度确定4种不同的局部处理方式（缩小法、膨胀法、消平法和桥梁法）在不同雷诺数范围内各自最佳的局部处理尺寸范围。研究结果表明,在研究中可直接利用等直径苹果替代苹果真实形状,在整个雷诺数范围内两者之间的各种边界层物理量最大相对偏差在15%左右,桥梁法在4种接触点局部处理方式中模拟准确性最高,通过对比实验验证,温度模拟值与实测值具有较好的一致性,其最大均方根误差为1.514℃,平均相对误差在20%左右。

满足物流要求的优质苹果的包装设计

包装是物流系统的一部分,在物流过程中有着很重要的作用。本文基于物流过程对包装的要求以及优质苹果的特点,选择适当的包装方法对其进行合理的包装设计,包括缓冲包装设计,瓦楞纸箱设计,防潮包装设计和运输包装标志的确定,保护优质苹果在物流过程中不受损害,实现包装功能和物流目标。

基于共同配送视角的冷链物流优化研究——以陕西省苹果产业物流为例

基于共同配送视角构建出冷链物流路径优化模型。通过模型分析可以看出:共同配送能够降低冷链物流运输成本、提高冷链物流运输质量、加快冷链物流发展。再以陕西省苹果产业冷链物流为例,证明了共同配送的有效性,并为陕西省苹果冷链物流的发展提供了一个合理的模式。

面向物流环节的苹果品质影响研究

目前苹果流通过程由于受到各种因素影响,特别是物流作业环节,其重要品质参数,包括颜色、硬度等都会发生较大改变,成为影响苹果流通质量的关键问题。系统梳理了苹果在物流环节的影响因素,基于研发的专用测试系统,从颜色和硬度两个方面对碰撞、冲击等因素的影响做了定量分析,并对如何减少苹果损伤问题提出了相应的解决措施。

矮化自根砧苹果苗木生长动态及其根系分布特征

【目的】明确矮化自根砧苹果苗木的生长规律及根系空间分布特征,为苗木科学管理提供依据。【方法】以1年生矮化自根砧苹果苗木（富士/M9）为试材,在2013-03-29-2013-10-23,每隔7d对其地上部主干长度进行测量,利用原位取土法每隔30d将根系全部挖出,分析苗木的生长动态和根系空间分布特征。【结果】1年生矮化自根砧苹果苗木主干生长近似＂S＂型生长曲线,可分为生长渐增期、生长快增期、生长缓增期3个时期,Logistic生长曲线能很好地反映其生长动态。地下部根系在6、9月份出现2个生长高峰,7、8月份根系死亡量较大;在水平方向,吸收根、输导根主要分布在距树干0~30cm处;在垂直方向,吸收根集中分布于0~40cm土层,输导根全部分布于0~30cm土层;根系根长密度在水平方向、垂直方向均呈指数衰减规律;通过建立二维根系密度方程,可知1年生矮化自根砧苹果苗木根系分布符合二维指数分布。【结论】矮化自根砧苹果苗木根系构型呈无主根、侧根集中分布于砧木中下部、水平根分布多而广等特点。

山西省苹果冷链物流现状及对策研究

山西是我国重要的苹果生产基地,随着山西省果业规模化、产业化快速发展和消费者对水果需求的不断增加,冷链物流已成为影响果品竞争力的关键因素和运输领域不可或缺的重要组成;然而,目前山西苹果冷链物流发展尚处于起步阶段。针对苹果冷链物流设施落后、冷链效率低、物流成本高等问题,从政策保障、法律监管、标准制定、冷链设施以及信息平台建设等方面提出了相应的发展对策,以期为促进苹果产业的进一步发展提供参考。

陇东旱塬苹果果园农户生草意愿及影响因素分析

果园生草作为一项生态环保型的果园管理技术,已在我国许多地区得到了推广应用。本研究通过对陇东典型旱塬苹果种植区庆阳市172户农户的问卷调查,分析了果园生草现状及农户生草意愿;并运用Logistic回归模型对当地农户实施果园生草意愿的影响因素进行了定量分析。结果表明,目前陇东旱塬果园生草的应用率为23.8%,36%的农户有果园生草的意愿。在影响果园生草意愿的因素中,果园类型(P<0.01)、农户对果园生草技术的了解程度(P<0.01)、能否及时获取技术信息(P<0.01)和户主文化程度(P<0.05)对农户的果园生草意愿呈显著影响。

山东省苹果种植户化肥减施意愿影响因素分析

化肥减施是治理农业面源污染、推进农业可持续发展及乡村振兴战略的重要举措。基于山东省227份苹果种植户问卷调查数据,以计划行为理论为指导,运用二元Logistic模型对影响苹果种植户化肥减施意愿的显著因素进行分析。研究结果表明:生态补偿政策下,有81.50%的苹果种植户具有化肥减施意愿;苹果种植户的行为态度、主观规范和知觉行为控制均正向影响化肥减施意愿,其中,化肥减施的必要性认知、过量施肥的危害性认知、邻里示范效应、政策指引效应、对经济效益影响的承受能力、化肥减施技术的接受能力、对化肥减施政策的了解程度变量是影响苹果种植户化肥减施意愿的重要因素。据此,为引导农户主动积极参与化肥减施,政府应加强宣传推广,提升苹果种植户化肥减施的认知水平;强化邻里示范与政策引导作用,营造浓厚的积极参与化肥减施的社会氛围;完善并落实化肥减施的生态补偿政策,激发苹果种植户的积极性。

“互联网+”背景下阿克苏果农新媒体使用意愿及影响因素分析

近年来新疆苹果产业面临生产成本攀升、产品质量参差不齐、产品销售渠道单一、运输困难、小农户与大市场脱节等问题,新疆林果业与"互联网+"深度融合已是大势所趋。新媒体作为基于互联网的新型媒体,具有交互性、传播快、平民化、门槛低、运作简单等特点,可以用于产品宣传。通过新媒体平台将种植环境及产品质量进行展示,可以提高曝光度,进而增加收益。基于对阿克苏地区果农的问卷调查数据,通过多元Logistic回归模型分析果农对新媒体的使用意愿及影响因素,结果发现影响新媒体使用的因素中最强烈的分别是学历、政策、年龄。最后,提出了加强"互联网+农业"知识培训、增强互联网产业融合、促进专业合作社发展、引进高级技术型及管理型人才等推动新疆果农新媒体使用的政策建议。