Blockchain Papers

Jan Ole Berndt

No abstract is available for this record.

Bernd Scholz‐Reiter, Sergey Dashkowskiy, Michael Görges, Thomas Jagalski · 5 authors

No abstract is available for this record.

Kevin Shang, Jing-Sheng Song, Paul Zipkin

This paper studies a periodic-review, serial supply chain in which materials are ordered and shipped according to (R,nQ) policies. Three information scenarios are considered, depending on the level of information available: echelon, local, and quasilocal. In the echelon scenario, each stage can access the inventory and cost information within its echelon (comprising the stage itself and all downstream stages); in the local scenario, each stage only accesses its own local information. Finally, in the quasilocal scenario, each stage knows its local information, plus the actual customer demands. We propose coordination schemes that regulate the stages to achieve the supply chain's optimal cost under each information setting. All these coordination schemes fit comfortably within an emerging practice called supply chain finance, which includes the organization and technology needed to implement them.

Daniel Roy, Didier Anciaux, Thibaud Monteiro, Latifa Ouzizi

The purpose of this paper is to propose a new approach for the supply chain management. This approach is based on the virtual enterprise paradigm and the used of multi-agent concept. Each entity (like enterprise) is autonomous and must perform local and global goals in relation with its environment. The base component of our approach is a Virtual Enterprise Node (VEN). The supply chain is viewed as a set of tiers (corresponding to the levels of production), in which each partner of the supply chain (VEN) is in relation with several customers and suppliers. Each VEN belongs to one tier. The main customer gives global objectives (quantity, cost and delay) to the supply chain. The Mediator Agent (MA) is in charge to manage the supply chain in order to respect those objectives as global level. Those objectives are taking over to Negotiator Agent at the tier level (NAT). These two agents are only active if a perturbation occurs; otherwise information flows are only exchange between VENs. This architecture allows supply chains management which is completely transparent seen from simple enterprise of the supply chain. The used of Multi-Agent System (MAS) allows physical distribution of the decisional system. Moreover, the hierarchical organizational structure with a decentralized control guaranties, in the same time, the autonomy of each entity and the whole flexibility.

Vijayender Reddy Nalla

Companies can no longer perceive themselves as stand-alone entities in the business environment. As a result of major trends such as Globalization, Outsourcing and Off-shoring, companies have more and more begun to perceive themselves as part of a chain (or network) of companies. With the increased length of chains and the increased interdependencies between organizations, coordination between such entities has become increasingly important. Due to the fact that Supply Chain (SC) decision making is distributed over various players, one of the key managerial challenges in any SC consisting of autonomous organizations is to align decisions. Typically, each organization will take decisions to optimize its own performance. But what is best for an individual organization is not always best for the SC, so that un-aligned decision making usually leaves the SC in a state of sub-optimization. Contract mechanisms might be useful to tackle such challenges. Ideally, contract mechanisms ensure that the SC is optimized as if it were a single unit (coordination) and is designed such that all players benefit from working together through the coordinating mechanism (win-win). A SC is said to be coordinated (or optimized) if it achieves the same profit as it would in a centralized situation (or full partnership). Furthermore, win-win is said to be achieved if all the players in the SC make greater profits when compared to the decentralized decision-making situation. The effectiveness of contract mechanisms lies in their design; the decision-making authorities remain unchanged, but the incentives of the various SC entities are aligned in such a way that optimizing one’s own situation “automatically” optimizes the SC. This dissertation aims to devise contract mechanisms in various SC settings. As such it contributes to the understanding of where and how such mechanisms can coordinate operational and marketing decisions across autonomous organizations and lead to win-win. The focus is on a range of operational and marketing decisions like pricing and replenishment, promotions, service level and assortments (number of products in the product line). The methodology used in the dissertation is modeling in combination with mathematical optimization, i.e., the tools and methodology of operations research / management science are applied. The typical setting is as follows. In a two player SC with a Supplier and a Buyer, the Supplier sells the product at a wholesale price to the Buyer. The Buyer then fixes the final selling price and sells it to the end-consumer. In a traditional decentralized situation, the Supplier charges a higher wholesale price and the Buyer charges a higher retail price and orders a lower quantity than what is optimal for the entire SC. In this setting contracts like revenue-sharing and quantity discounts are designed and analyzed which can induce the Buyer to fix the final selling price and order quantity at the SC optimal level. In essence, the contract mechanisms coordinate both pricing and replenishment decisions and provide win-win opportunities. Similarly, when the end-consumer demand can be influenced by promotions, it is shown that non-optimal promotional decisions are made in a decentralized situation. A new rebate mechanism is designed to coordinate the promotional decisions and provide win-win opportunities. Furthermore, it is shown that contract mechanism can coordinate service level and product line decisions and provide win-win opportunities. The above decisions are analyzed in a wide variety of demand and supply conditions, i.e., in a variety of SC settings. For each research problem a variety of contract mechanisms have been designed and analyzed to address the issues of coordination and win-win. In all models studied, we were able to find at least one mechanism for achieving coordination and providing win-win opportunities. Furthermore, relationships between the parameters of different contract mechanisms are established wherever possible. Also, the different mechanisms have been analyzed and reviewed from an implementation perspective. In this flat (globalized) world, we believe that incentive alignment will help businesses to deliver value to their customers and maintain or enhance their competitive positioning. Therefore, in our view, this thesis will aid businesses with an important tool in aligning the incentives within their SCs.

Thibaud Monteiro, Daniel Roy, Didier Anciaux

A new approach of coordination of decisions in a multi site system is proposed. It is based this approach on a multi-agent concept and on the principle of distributed network of enterprises. For this purpose, each enterprise is defined as autonomous and performs simultaneously at the local and global levels. The basic component of our approach is a so-called Virtual Enterprise Node (VEN), where the enterprise network is represented as a set of tiers (like in a product breakdown structure). Within the network, each partner constitutes a VEN, which is in contact with several customers and suppliers. Exchanges between the VENs ensure the autonomy of decision, and guarantiee the consistency of information and material flows. Only two complementary VEN agents are necessary: one for external interactions, the Negotiator Agent (NA) and one for the planning of internal decisions, the Planner Agent (PA). If supply problems occur in the network, two other agents are defined: the Tier Negotiator Agent (TNA) working at the tier level only and the Supply Chain Mediator Agent (SCMA) working at the level of the enterprise network. These two agents are only active when the perturbation occurs. Otherwise, the VENs process the flow of information alone. With this new approach, managing enterprise network becomes much more transparent and looks like managing a simple enterprise in the network. The use of a Multi-Agent System (MAS) allows physical distribution of the decisional system, and procures a heterarchical organization structure with a decentralized control that guaranties the autonomy of each entity and the flexibility of the network.

Franco Guidi-Polanco, Claudio Cubillos, Giuseppe Menga

This work presents our agent-based architecture for the development of Global Automation Systems. These systems consist of software applications that manage all the processes in a network of enterprises, in distributed, decentralized and autonomous way. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

M. Georgoudakis, Christos Alexakos, Αθανάσιος Καλογεράς, John Gialelis · 5 authors

This paper presents a distributed system architecture that is based on the prominent industrial standard ANSI / ISA-95 and utilizes ontologies and web services in an attempt to address the challenge of interoperability in the industrial enterprise environment in an efficient way. Work presented in this paper is partly financed by the PABADIS'PROMISE project framework (FP6-IST-016649). This paper proposes an agent-based approach, which assisted by an appropriate ontology attempts to match the properties of information agents and the generic requirements of the industrial automation domain in order to address automation information handling problems. The novelty of the approach lies in the utilization of ontological descriptions of the resources and the processes invoked by intelligent agents, while it couples production - related processes with shop floor equipment via standard Device Description Language, avoiding ad-hoc implementations. The benefits of this approach are optimal interoperability among the agents and adaptability in dealing with considerable changes in the industrial environment. Although ontological description of resources is hardly a new concept, the problem associated with this approach is the ad hoc methodology of description usually followed which renders the ontology to a dictionary usable only within the boundaries of the enterprise, thus of limited interoperability. The proposed framework is based on emerging web technologies such as Web Services, Ontology Web Language (OWL) and JADE (Java Agent Development Framework) agent platform while it introduces the following features: - ANSI / ISA 95 (2) based ontology implementation is used in order to model knowledge within the industrial environment domain.

JDA Carvalho, NA Moreira, LCM Pires

This paper presents the concept of Autonomous Production Systems (APS), which are the organizational units upon which enterprises can be built and managed in order to better face the globalization challenges. We believe that companies organized as networks of APSs are better prepared to respond to the new economy challenges than organized in a hierarchical fashion. The way a traditional company can be reorganized in terms of a network of APSs using decentralized management is also explored in this article. We propose an approach to create and operate Virtual Enterprises either based on APSs or based on traditional companies. A Production Planning and Control system to operate Virtual Enterprises is also proposed in this paper using the concept of Bill of Materials and Movements.

John Allen Neal

The development of a "Next Generation Manufacturing System" is currently an active area of research worldwide. The research described in this dissertation addresses one sub-element within this research area; namely, the demonstration of a decentralized, automated production architecture. The goal of the work is to increase the ability of a manufacturing enterprise to respond to rapid technological and market change in the post-2000 global economy. The research is comprised of three objectives; definition of a decentralized organizational structure of autonomous production activities, implementation of the defined organization in a real world manufacturing environment, and a comparison of historical (centralized architecture) performance data and decentralized performance data. To accomplish these objectives, the proposed production architecture is implemented at a real world manufacturing site and performance data are acquired and tested against a stated hypothesis. The research entails the modification of a selected electronics module assembly activity in the following ways: 1) comprehensive automation of assembly processes; 2) simplification of production practice through a minimization of operator interaction and a reduction of assembly transaction points requiring operator intervention; and 3) restructuring of organizational functions resulting in decentralization and operational autonomy. The null hypothesis was successfully rejected and it was shown that the implementation of automation, simplification, and decentralization resulted in an enhancement of production performance (i.e., a reduction in throughput time, labor cost, overhead cost, and total product cost) without degrading production quality. A test of the null hypothesis based on the data indicates a statistically significant (i.e., p less than or equal to 0.05) reduction in throughput time, labor cost, overhead cost, and total product cost while no statistically significant difference in the before and after production quality data was shown. A possible interpretation of these results is that the implementation of automation, simplification, and decentralization did result in a reduction in the labor cost, overhead cost, and total product cost and did not result in a degradation in production quality.

Thomas Thierauf

We investigate the computational complexity of the isomorphism problem for one-timeonly branching programs (BP1-Iso): on input of two one-time-only branching programs B 0 and B 1 , decide whether there exists a permutation of the variables of B 1 such that it becomes equivalent to B 0 . Our main result is a two-round interactive proof for BP1-Iso, the complement of BP1-Iso. The protocol is based on the Schwartz-Zippel Theorem to probabilistically check polynomial idendities. As a consequence, BP1-Iso cannot be NP hard unless the polynomial hierarchy collapses. We extend the protocol to get an interactive proof to decide the non-isomorphism of multivariate polynomials over an arbitrary field. Finally, we show that BP1-Iso has a zero-knowledge interactive proof. 1 Introduction An interesting computational issue is to decide the equivalence of two given programs with respect to some computational model as, for example, Boolean circuits, branching programs, or Boolean formulas. A more ge...

Michael Rohloff

No abstract is available for this record.

キヨタカ シミズ, Kiyotaka Shimizu, 清孝 志水

We study a two-level system having N local systems in the lower level subordinate to a central system in the higher one, such that both central and local systems have decision-making units. The central system is a coordinating agency and the local ones are semi-autonomous operating devisions. The basic principle of planning for this organization is that the central system allocates resources so as to optimize its own objective, while the local ones optimize their own objectives using the given resources. A local objective function, fn, is a function of the lower level decision variable vector x=(x1,・・・, xN) and the higher level one a=(a1,・・・, aN), where an is a resource vector allocated to the local system n. Since the functions ■ are mutually independent, the lower level composes a multi-objective system, in which the lower level decision-makers minimize a vector objective function f =(f1,・・・,fN) with respect to x in cooperation with each other. Thus, the lower level generates a set of noninferior (i.e. Pareto optimal) solutions ■(a) being parametric with respect to a. The central decision-maker, then, chooses the optimal resource allocation a⁰ and the best noninferior solution ■⁰ corresponding to a⁰ from among a set of ■(a). The above problem becomes a decentralized two-level optimization, when the local system contains only its own variables (xn, an). Several theorems and iterative algorithms for the formulated problems are obtained by use of mathematical programming techniques.