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An integer multiple objective non‐linear mathematical programming formulation is developed for simultaneously forming part/machine cells. In the proposed model, generic capability units which are termed as resource elements are used to define the processing requirements of parts and processing capabilities of machine tools. Machine capabilities are not generally taken into account in the previous cell formation procedures. Explicit consideration of unique and overlapping machine capabilities can result in better manufacturing cell designs with higher utilisation levels and less machine duplication. The proposed cell formation model has distinguishing features. Several important cell formation objectives, such as minimisation of part dissimilarity (based on production requirements and processing sequences of parts) in formed cells, minimisation of cell load imbalance, and minimisation of extra capacity requirements for cell formation, are considered. In order to solve the mathematical programming model, a simulated annealing algorithm is developed. Cooperative game theoretic approach is applied for evaluating multiple objectives.

Builds on previous research by the authors to establish a mathematical representation of the surface roughness of stereolithography (SL) parts. It is the intention of the research to use this modelling technique as a design tool for defining optimum build orientation and planning post‐process finishing operations. During the development of this model, a number of in‐process attributes inherent in SL were seen to affect surface deviation. Most notably the phenomenon known as “print‐through” on down‐facing planes produces a build orientation envelope of very smooth surfaces. Although capable of providing low roughness over some 50°, print‐through smoothing cannot easily be extended to other angles, hence complementary processes for surface smoothing must be developed. Discusses a number of possible solutions, showing how the generation of a meniscus between layers can prove beneficial in reducing SL surface roughness, hence reducing the need for lengthy manual finishing operations.

This paper offers a quick overview of Cameron's contingency theory of conflict management in public relations. It then applies the theory to three cases that occurred during the 1996 Summer Olympic Games that were taken from the policy position papers, notes, diaries and tape recordings of C. Richard Yarbrough, Managing Director‐Communications of the Atlanta Committee for the Olympic Games (ACOG). The areas analysed include: the moving of preliminary volleyball matches from one venue to another which was forced by conflict between gay activists and local politicians who passed an anti‐gay resolution — a sustained effort at accommodation that shifted to advocacy; conflict between the ACOG board of directors and the media resulting from the disclosure of ACOG executive salaries — a strong advocacy stance that led to compromise; and conflict threatened between ACOG and a minority minister who was disgruntled about an Olympic sponsor — a case of marginality too insignificant to bother with. The cases not only illustrate and support factors in the contingency theory, but highlight the impracticality and inflexibility of two‐way symmetrical or mixed‐motive public relations as models of choice.

The US Government is challenged to maintain pace as the world’s de facto provider of space object cataloging data. Augmenting capabilities with nontraditional sensors present an expeditious and low-cost improvement. However, the large tradespace and unexplored system of systems performance requirements pose a challenge to successful capitalization. This paper aims to better define and assess the utility of augmentation via a multi-disiplinary study.

Hypothetical telescope architectures are modeled and simulated on two separate days, then evaluated against performance measures and constraints using multi-objective optimization in a heuristic algorithm. Decision analysis and Pareto optimality identifies a set of high-performing architectures while preserving decision-maker design flexibility.

Capacity, coverage and maximum time unobserved are recommended as key performance measures. A total of 187 out of 10¹⁷ architectures were identified as top performers. A total of 29% of the sensors considered are found in over 80% of the top architectures. Additional considerations further reduce the tradespace to 19 best choices which collect an average of 49–51 observations per space object with a 595–630 min average maximum time unobserved, providing redundant coverage of the Geosynchronous Orbit belt. This represents a three-fold increase in capacity and coverage and a 2 h (16%) decrease in the maximum time unobserved compared to the baseline government-only architecture as-modeled.

This study validates the utility of an augmented network concept using a physics-based model and modern analytical techniques. It objectively responds to policy mandating cataloging improvements without relying solely on expert-derived point solutions.

Changes in the traditional values, institutional context, and choice of change programs are currently shaping the postmodern science and practice of organization development (OD). These changes manifest themselves in powerful new value orientations, intervention frameworks, and practices that challenge OD's long-held beliefs in ethical and justice-based treatment. In this effort, traditional and new paradigm ethical dilemmas are explored, as well as their relationship to four postmodern practices and five emergent intervention techniques. Components of distributive, procedural, and interactional justice are explained relative to change management programs generally, and to emergent techniques specifically. Published case illustrations are used to depict new paradigm ethical dilemmas and opportunities to create a “just change.”

For many applications, including space applications, the usability and performance of a component is dependent on the surface topology of the additively manufactured part. The purpose of this paper is to present an investigation into minimizing the residual surface roughness of direct metal laser sintering (DMLS) samples by manipulating the input process parameters.

First, the ability to manipulate surface roughness by modifying processing parameters was explored. Next, the surface topography was characterized to quantify roughness. Finally, microthruster nozzles were created both additively and conventionally for flow testing and comparison.

Surface roughness of DMLS samples was found to be highly dependent on the laser power and scan speed. Because of unintended partially sintered particles adhering to the surface, a localized laser fluence mechanism was explored. Experimental results show that surface roughness is influenced by the varied parameters but is not a completely fluence driven process; therefore, a relationship between laser fluence and surface roughness can be incorporated but not completely assumed.

This paper serves as an aid in understanding the importance of surface roughness and the mechanisms associated with DMLS. Rather than exploring a more common global energy density, a localized laser fluence was initiated. Moreover, the methodology and conclusions can be used when optimizing parts via metal additive manufacturing.

This chapter focuses on the increasing use of both assistive technology (AT) and teacher assistants (TAs) to support students with disabilities within the inclusive classroom, and why it is vital that teacher assistants have appropriate training in the area of AT. A description of assistive technology and its role in inclusion of students with special needs is provided along with a description of training in assistive technology that was undertaken with teacher assistants. Implications for training and support of teacher assistants in the area of assistive technology are also discussed.