Inter-firm collaborations and supply chain coordination: review of key elements and case study

Considering the effects of globalisation, the increase of production and energy costs, and the introduction of advanced technologies, companies need to change their way of doing business if they want to stay competitive. One way of doing this is to establish collaborations with suppliers, distributors and retailers, in order to exchange products efficiently and create value for customers. Nevertheless, the structure of the collaboration must be designed carefully and some coordination mechanisms must be implemented to support this way of doing business. In this article, we first analyse: why companies work together, how they should build their partnership, and which strategies they can implement to facilitate coordination of supply chain activities. We then report a case study of collaboration in the forest industry that shows the benefits of implementing coordination mechanisms as well as the necessity of using incentives to better share these benefits.     

Using vulnerability performance indicators to attain food supply chain robustness

High effectiveness and leanness of modern supply chains (SCs) increase their vulnerability, i.e. susceptibility to disturbances reflected in non-robust SC performances. Both the SC management literature and SC professionals indicate the need for the development of SC vulnerability assessment tools. In this article, a new method for vulnerability assessment, the VULA method, is presented. The VULA method helps to identify how much a company would underperform on a specific Key Performance Indicator in the case of a disturbance, how often this would happen and how long it would last. It ultimately informs the decision about whether process redesign is appropriate and what kind of redesign strategies should be used in order to increase the SC's robustness. The applicability of the VULA method is demonstrated in the context of a meat SC using discrete-event simulation to conduct the performance analysis.     

Waste identification diagrams

Value Stream Mapping (VSM) is a very popular tool in lean environments to represent production flows, mapping value stream of a product or family of products, and helps to identify some types of waste. Although very popular, this tool has some limitations as already described in many publications, especially in terms of restrictions in showing most types of waste as well as in its inability to represent various production routes. The purpose of this study is to introduce the waste identification diagram (WID), a new tool to represent production units with its different forms of waste, which overcomes some VSM limitations. The originality of WID comes from the use of its symbols’ dimensions to convey, in a visual and immediate way, relevant information about a production unit. In this paper, WID is applied on a production unit of a lift manufacturer, for testing its performance and comparing it to VSM. The main findings are that WID is in general more effective than VSM in terms of representation of complex production units and in terms of identification of more forms of waste. WID must however overcome some of its limitations such as the lack of information-flow representation and the links to suppliers and clients.     

A sequential design for a clinical trial with a linear prognostic factor

We study a randomized adaptive design to assign one of the L$L$ treatments to patients who arrive sequentially by means of an urn model. At each stage n$n$, a reward is distributed between treatments. The treatment applied is rewarded according to its response, 0?_Yn?1$0?Y_n?1$, and 1-_Yn$1-Y_n$ is distributed among the other treatments according to their performance until stage n-1$n-1$. Patients can be classified in K+1$K+1$ levels and we assume that the effect of this level in the response to the treatments is linear. We study the asymptotic behavior of the design when the ordinary least square estimators are used as a measure of performance until stage n-1$n-1$.     

EXTERNAL AIDS FOR SOCIAL MEMORY

Collective or social memories are not just a way for accumulating and preserving but also for sharing and developing knowledge. Indeed, as knowledge is made explicit and elaborated by a community, it enriches the local culture and the current practices, becoming a basis for communication and learning. This paper addresses the concept of 'social memory' in a specific 'community of practice': teachers and students of primary schools. The work is developed within HIPS1 (Hyper Interaction within Physical Space), a three-year (1997-2000) research project funded by the European Commission within the I 3 (I-Cube) Programme. HIPS is a hand-held location-aware tourist guide that delivers information related to the surrounding space mainly reacting to the physical movements of visitors (Benelli et al . 1999). The guide is designed to minimize the boundary between the physical space and the related information through a number of situated and contextual-aware interaction mechanisms. In the paper we present a specific application of HIPS as tool to support the creation of a social memory. First, we illustrate the theoretical framework, the cultural psychology (Vygotsky 1978), which we adopted to design the tool as an external aid for social memory. Afterwards we describe the user study and the design process that resulted in the development of an early prototype. The conclusions are a reflection about the use of new technology to open new learning opportunities for students.     

Signed compound poisson integer-valued GARCH processes

Abstract

We propose signed compound Poisson integer-valued GARCH processes for the modeling of the difference of count time series data. We investigate the theoretical properties of these processes and we state their ergodicity and stationarity under mild conditions. We discuss the conditional maximum likelihood estimator when the series appearing in the difference are INGARCH with geometric distribution and explore its finite sample properties in a simulation study. Two real data examples illustrate this methodology.     

The Sharing Economy Globalization Phenomenon: A Research Agenda

Sharing economy firms have been able to achieve global levels of success at an unprecedented pace. In this study, we focus specifically on internet-based firms that allow rent appropriation from temporary utilization of underutilized assets. By looking at these firms' main characteristics and the current dynamics revolving around their internationalization process, we develop a framework to guide future research drawing from a business ecosystems perspective. The business ecosystem approach is a promising theoretical lens to assess this phenomenon due to its more holistic view of multisided network effects and multiple stakeholders' participation that can vary across nations. We note that the sharing economy phenomenon has spurred worldwide adoption of platform businesses which, in turn, creates a great opportunity for future research to extend current theories by exploring why, when, and how these firms expand into new countries. We argue that further research on sharing economy firms and its interactions with different national ecosystem configurations can provide important insights to theory as well as relevant information to managers and policymakers.     

The Social Construction of the Profession of Probation Counsellor: An Analysis of the Instrumental and Institutional Framework

The purpose of this article is to develop an interpretative model regarding the institutional and instrumental frameworks of the social construction of the profession of probation counsellor in N.E. Romania and the Republic of Moldova. The research was conducted after a major penal reform in both countries, which significantly changed the function of the probation system, which is very new. The research was conducted through individual and group interviews with the probation counsellors and other people involved in applying non-custodial punishments. The data analysis starts from the Grounded Theory method. The most important results have targeted the modifications of the regulatory frameworks of probation, a fact which leads to a series of problems related especially to the inadequacies between the different normative frameworks applied, the case overloads and the partial inadequacy of the models of practice based on the experience of other states (especially the U.K. and Norway) to the Romanian and Moldavian reality. The research highlights a mixed model of probation with elements of restorative justice, which interferes with the retributive model, and with the model of justice centred on human rights.     

Some issues related to the topological aggregation of preferences

This paper deals with the topological approach to social choice theory initiated by Chichilnisky. We study several issues concerning the existence and uniqueness of Chichilnisky rules defined on preference spaces. We show that on topological vector spaces the only additive, anonymous, and unanimous aggregation n-rule is the convex mean. We study the case of infinite agents and show that an infinite Chichilnisky rule might be considered as the limit of rules for finitely many agents. Finally, we show that under some restrictions on the preference space, the existence of a Chichilnisky rule for every finite case implies the existence of a weak Chichilnisky rule for the infinite case.