Protecting mobile agents＇ data using trusted computing technology

Even with attractive computational advantages, mobile agent technology has not developed its full potential due to various security issues. This paper proposes a method called Private Key Consignment to solve the problem of how to protect the data carried by mobile agents. It exploits new functionalities and mechanism provided by the trusted computing technology, and adopts both public key and symmetric key cryptographic means for data and key protection. The most notable feature of this method is that it protects the private key of the agent by consigning it to a tamper proof hardware, thus, enabling convenient and secure use of the private key. It provides a new scheme of mobile agents＇ data protection.     

多任务小批量流水线遗传算法仿真与实施

文章阐述了在流水线调度时,可利用遗传算法计算出工件的最短通过时间, 但这并非最佳方案,应同时考虑交货期的影响、设备的负荷率和员工加班等问题.在设计过程中,根据多任务,小批量流水线生产的特点,改进常规遗传算法,设计出一种基于交货期的遗传算法,可以很快地搜索到最优个体,并实例证明了其可行性.     

自动发货的研究与应用

随着MES库房管理的上线运行,销售公司通过在运行阶段的业务操作,提出了一个突出的问题,销售发货仅在MES操作出库,由程序自动进行ERP系统销售模块的发货处理,减少在两个系统之间来回切换导致的错误,同时减少业务人员的操作环节.基于销售人员提出的问题,基于自动发货的原理进行研究,完成了程序模拟手动发货的全过程,并在实际中进行应用,取得了非常好的效果.     

论徐州地区传统货代向现代物流转化问题

随着铁路多元经营战略的调整以及路外市场的竞争加剧,徐州铁路货运代理业面临新的机遇和诸多挑战。本文首先探讨了徐州铁路货运代理业与现代物流的差距。然后分析了铁路货代发展物流的优势以及铁路货运代理自身存在的问题,最后提出了解决这些问题的建议方法。     

Should competing original equipment manufacturers outsource procurement activities under asymmetric cost information?

This paper considers a supply chain in which two competing heterogeneous original equipment manufacturers (OEMs) outsource production to a common contract manufacturer (CM) that possesses private cost information. Along with production outsourcing, the OEMs can either purchase components by themselves and only assign the production tasks to the CM (Consignment), or delegate both the procurement and production tasks to the CM (Turnkey). The main question we address is whether the OEMs should adopt Consignment or Turnkey. To answer this question, we first analyse the OEMs’ optimal mechanism design problems under three scenarios: both OEMs adopt Consignment strategy; both OEMs adopt Turnkey strategy; one OEM adopts Consignment and the other one adopts Turnkey. Building upon the OEMs’ equilibrium decisions under each scenario, we then characterise the equilibrium outcome for the procurement game. The results show that the CM’s procurement cost distribution and the market size play critical roles in the equilibrium outcome. Additionally, we find that both the competition intensity and cost heterogeneity between the OEMs affect the equilibrium outcome.     

Consignment and vendor managed inventory in single-vendor multiple buyers supply chains

In this paper we model a consignment (CS) and vendor-managed inventory (VMI) policy for a single vendor and multiple buyers supply chain with known demand. We study three vendor–buyers partnerships: (i) the vendor and the buyers act independently, (ii) the vendor enters in a vendor-managed inventory consignment (VMI&CS) partnership with the buyers and (iii) the vendor and the buyer belong to a vertically integrated firm where a single decision maker decides about the ordering policies. We use relationships (i) and (ii) to study the benefits of the VMI&CS agreement. We provide analytical and numerical results. We find that such an agreement is more beneficial when the vendor has a flexible capacity. It is also more attractive to buyers when they have significant order costs and the vendor's setup cost is not large. Finally we find that under VMI&CS the vendor will tend to make more frequent shipments with smaller lots.     

基于Web的机械加工仿真委托服务平台

根据机械加工仿真的需求，设计了仿真委托服务平台来实现远程加工模拟，优化和仿真，在Internet/Web技术和机械加工仿真发展的基础上，研究远程委托仿真的条件与环境，借助统一建模语言对委托过程进行建模，委托服务平台实现了委托流程管理，并为仿真系统需求方与实施方提供通讯环境与合作空间，最后，以实例说明该平台的有效性。     

Vendor managed inventory with consignment stock for supply chain with stock- and price-dependent demand

This paper presents a single vendor–single buyer coordinated model. The vendor produces a single deteriorating item and transfers it to the buyer in equal shipments. The model is based on vendor managed inventory with consignment stock (VMI-CS) agreement in which the vendor uses the buyer’s warehouse. The buyer stocks items both on his shelf and in his warehouse. The demand is assumed to be linearly sensitive to inventory level and selling price. The objective is to determine variables that maximise the total profit. An exact solution procedure is proposed to find the optimal solution. Numerical results show that supply chain members will benefit from the advantages of economies of scale in coordinated model with VMI-CS policy.     

A supply chain model with vendor-managed inventory,consignment, and quality inspection errors

This paper considers the integration between quality control and production inventory control in supply chain management. Specifically, we study the effect of inspection errors on the costs incurred in a supply chain system with a single vendor and multiple buyers. In this system, the vendor enters into a vendor-managed inventory (VMI) and a consignment stock (CS) partnership with several buyers. We assume that the items made by the vendor are not in perfect quality, but they contain a given proportion of defective units. We also assume that quality inspection of these items by the buyers is subject to sampling errors. Three cases indicating to different levels of supply integration are considered: VMI–CS system, traditional system and integrated system. For each case, a mathematical model is formulated, an optimum solution is developed, and a numerical example is solved.     

Consignment stock policy with unequal shipments and process unreliability for a two-level supply chain

This paper considers a vendor managed inventory model with consignment stock policy in which a single vendor delivers a single product to a single buyer in unequal-sized shipments. The vendor’s production process may produce some defective items during a production run. The buyer performs a screening process immediately after receiving each delivery from the vendor and the vendor bears the warranty cost of defective item, if any. The buyer either scraps or repairs the defective items by sending them to a repair factory. The average expected profit of the integrated system is derived using renewal reward theorem and a solution procedure is suggested to determine the optimal shipment policy of the vendor. Numerical examples are taken to determine both the equal and unequal shipment policies and compare their relative performances.