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The purpose of this paper is to develop a simple, easy to implement powder delivery strategy for solid freeform fabrication (SFF) processing.

A specially designed “tower nozzle” located at the center of the processing area dispenses the feedstock powders continuously and uniformly onto the processing area, where powders accumulate progressively as a flat powder bed. During the dispensing, powders are selectively consolidated by melting and solidification using a laser beam which was scanned in a predefined pattern using a galvo‐mirror scan head.

Experiments performed with AISI H13 steel show that the tower nozzle powder delivery strategy is suitable for SFF processing.

Both powder delivery and laser consolidation are performed simultaneously and without interruption with simple apparatus. No powder delivery scrapers or rollers are used.

The main characteristics of a prototype tower nozzle and the typical processing conditions used to form thin wall AISI H13 steel shapes are presented.

The purpose of this paper is to take a critical, analytical approach to explore the growth and spread of Lean through the academic and practitioner community over the last 25 years to understand the impact of the book The Machine that Changed the World on management thinking.

A comprehensive and systematic review of the extant literature of lean was undertaken and analysed critically to observe patterns and trends that could explain the acceptance of Lean as an operations management philosophy. The review spans from 1987 to 2013. To enable us to effectively manage and understand the diffusion of this literature a database, the Lean Publications Database, was constructed. The number of publications has been adjusted to compensate for growth in the total number of articles published in the same period.

Lean has evolved to be one of the best-known, yet fiercely debated, process improvement methodologies. It emerged during a proliferation of such methodologies in the business and management literature. Lean has developed from a generic description of Toyota Production System (TPS) to a particular type of organisational and management intervention focused on best practice and process improvement methodologies.

This paper provides the first comprehensive review of the Lean literature, from the perspective of Lean as the unit of analysis. It covers both sides of the academic debate and categorises the progression of Lean from its origins as a generic description of TPS to a movement that has changed management systems in many and diverse sectors.

This paper demonstrates how Lean research, application and thinking has evolved over 25 years from its origins in Japanese auto-manufacturing to a holistic value system that is applicable to all business sectors, both private and public.

In most empirical studies on Lean, the unit of analysis is the organisation. In this study, the unit of analysis is the Lean phenomenon itself. This paper examines the impact of The Machine that Changed the World on management thinking. In addition, it presents a step to developing an underpinning theory by linking Lean to the Theory of Swift, Even Flow. As such it is of interest to academics in the field of operations management and offers a contribution to knowledge. It is also likely to be of interest to policy makers. Considerable amounts of public money have been spent, and continue to be spent, on promoting Lean. Taxpayers and policymakers are likely to be interested in whether that expenditure is justifiable. 25 years of publications have been analysed to provide clarity around this popular approach to organisational improvement.

The purpose of this paper is to introduce an agent‐based model for partners' selection in inter‐organizational supply‐chains. Screening activities undertaken by the main contracting organization for the case of large project deliveries and parameters to be considered are identified, a multi‐level quantitative framework to support the decision‐making process in effectively selecting an efficient and a compatible set of partners is proposed. Different agent behaviours are introduced and modelled; their impact on the results of the bidding processes is analysed through a simulation model specifically developed for this purpose.

Among the biggest challenges, companies confront with is the finding of appropriate action lines, methods or IT tools to overcome problems introduced by the saturation of the market, fierce competition and downfall of entry‐barriers. The paper uses a paradigm that is seen as one of the most promising in responding to the needs of modern companies: the agent‐based paradigm.

Designing an efficient supply network greatly influences the level of uncertainty that a company is encountering. An agent‐based model may efficiently help the inter‐organizational networks partners' selection process. To operate effectively in open environments such as supply chains, agents must be adaptive. System/agents performance can be improved by doing what‐if simulation runs.

A further possible work direction, considering that nowadays a society must find a compromise between being internationally competitive and having a healthy environment, would be the introduction in the model of a special type of agent, namely the project delivery waste management agent.

In addition to contributing to the scientific literature, this research also aims at supporting practical business situations in the industry by creating a normative decision‐making model based on an agent‐based approach. The simulation model developed supports the tuning of parameters used in the evaluation process and makes possible analyzing the effect of different agent behaviours.

Research that identifies means to constrain the pre‐contracting selection problem for specific delivery chains as bridge constructions is needed. The paper details the particularities of such chains, and makes a presentment of roles of actors with impact on the assessment process. One specific of the approach is that in addition to participants as suppliers and main contracting organization also issues (goals) relevant in the supplier's appraisal process are represented by independent agents.

This paper is aimed at comparing cellular manufacturing with focused cellular manufacturing. We define focused cellular manufacturing as a layout scheme that groups components by end‐items and forms cells of machines to fabricate and assemble end‐items. It is not classified as a cellular manufacturing layout since it does not attempt to take advantage of process similarities. It also is not classified as a flow shop since there are no machines dedicated to individual operations and the machines are not arranged in a series. In addition, this research includes batching and assemble times in its criteria which few researchers in this area have done. The results indicate that the focused cellular manufacturing scheme has a batching advantage. This advantage out‐weighed the set‐up time reduction advantage of the cellular manufacturing scheme for average end‐item completion times and average work‐in‐process inventory levels. The cellular manufacturing scheme overcame the batching advantage only when there were small batch sizes or large set‐up time magnitudes.

Since its inception, the term ‘corporate governance’ (CG) has attracted mainstream attention, continuing to generate discussion among academics, practitioners and policy-makers. This heightened interest generally revolves around clarifying the principles of CG, both in theory and practice. This is particularly important in the context of emerging economies, where the sociocultural ethos and values often differ from those of most developed economies, where the CG concept was conceived and developed. In this vein, this chapter draws on empirical data to explore practical CG challenges faced by corporations in the Nigerian manufacturing and banking sectors. Nigeria is a country whose dominant national culture is one of high-power distance (HPD), which endorses servant-master relationships and encourages deference to authority. In this study, we found that HPD culture can undermine stakeholders’ ability to hold corporate executives to account on practices and behaviours that are antithetical to principles of corporate integrity and ethics, accountability, transparency, autonomy and stakeholder engagement, which in turn, leads to (and exacerbates) corporate misgovernance among businesses in the sectors. The theoretical and practical implications of the study are expatiated in the discussion section.

Nowadays manufacturers companies are increasingly compelled to navigate towards servitization. Different methods and approaches were proposed in literature to support them to switch from traditional product-based business model to product service systems (PSSs). However, new knowledge, capabilities and skills were needed to consistently develop PSSs, since they need a joint focus on both customer’s perspective and company’s internal performance and at the same time a proper support for the integration of product and service design. The purpose of this paper is to propose the Product Service System Lean Design Methodology (PSSLDM), a structured methodology to develop PSSs along their entire lifecycle.

Retrieving concepts from interpretative, interactive and system development research traditions, and strongly reminding the design research methodology framework, the adopted research methodology is composed of three main phases (observation and conceptualization, theory building and tool development, validation) and involved three heterogeneous companies.

This paper provides an overview of the PSSLDM, explaining how the different methods supporting its conduction should contribute to properly design an integrated PSS. Moreover, companies highlighted several benefits in the different stages along the PSS lifecycle deriving by the adoption of the PSSLDM.

The development of a platform based on the PSSLDM methodology raises a discussion on the possible changes needed by current Product Lifecycle Management (PLM) models and systems when they have to do with PSSs.

The PSSLDM enriches the already proposed SErvice Engineering Methodology, introducing new several components linked by lean rules in each of its phases (starting from customer analysis, going through solution concept and detailed design, until the offering analysis) and better supprting the deatil design of both prodcut and service components.

Kano River basin, which serves as the main source of water supply to metropolitan Kano, is also used as receiving body for industrial wastes from Sharada and Challawa industrial estates. Of the three major rivers in this basin, the Salanta river was found to receive the highest pollution from the industrial discharges with COD of 8,557.4mg/l, total solids of 16,934.6mg/l, hardness of 1,349.6mg/l CaCO₃, and ammonia nitrogen of 5,150.0mg/l. The Challawa river had COD of 598.7mg/l, total solids of 1,609.9mg/l, hardness of 1,332.0mg/l CaCO₃ and ammonia‐nitrogen 400mg/l. Both empty into the Kano river where the COD was 1,166.9mg/l, total solids 1,458.0mg/l, hardness 2,506.8mg/l and ammonia‐nitrogen 530mg/l. Although these rivers are being used extensively for water supply, irrigation, and fishing, the quality of the water was found to be unsuitable for these purposes. The paper suggests that waste water pre‐treatment by all industries, imposition of direct charges on industrial effluents by the regulating agency, as well as continuous monitoring and surveillance are required to ensure the protection of the water resources in the basin.

For over 60 years, Lerner's (1944) probabilistic approach to the welfare evaluation of income distributions has aroused controversy. Lerner's famous theorem is that, under ignorance regarding who has which utility function, the optimal distribution of income is completely equal. However, Lerner's probabilistic approach can only be applied to compare distributions with equal means when the number of possible utility functions equals the number of individuals in the population. Lerner's most controversial assumption that each assignment of utility functions to individuals is equally likely. This paper generalizes Lerner's probabilistic approach to the welfare analysis of income distributions by weakening the restrictions of utilitarian welfare, equal means, equal numbers, and equal probabilities and a homogeneous population. We show there is a tradeoff between invariance (measurability and comparability) and the information about the assignment of utility functions to individuals required to evaluate expected social welfare.