Search results

To seek to produce low‐voltage, soft mechanical actuators entirely via freeform fabrication as part of a larger effort to freeform fabricate complete electromechanical devices with lifelike and/or biocompatible geometry and function.

The authors selected ionomeric polymer‐metal composite (IPMC) actuators from the literature and the authors' own preliminary experiments as most promising for freeform fabrication. The authors performed material formulation and manual device fabrication experiments to arrive at materials which are amenable to robotic deposition and developed an SFF process which allows the production of complete IPMC actuators and their fabrication substrate integrated within other freeform fabricated devices. The authors freeform fabricated simple IPMC's, explored some materials/performance interactions, and preliminarily characterized these devices in comparison to devices produced by non‐SFF methods.

Freeform fabricated IPMC actuators operate continuously in air for more than 4 h and 3,000 bidirectional actuation cycles. The output stress scaled to input power is one to two orders of magnitude inferior to that of non‐SFF devices. Much of this difference may be associated with process‐sensitive microstructure of materials. Future work will investigate this performance gap.

Device performance is sufficient to continue exploration of SFF of complete electromechanical devices, but will need improvement for broader application. The feasibility of the approach for producing devices with complex, non‐planar geometry has not been demonstrated.

This work demonstrates the feasibility of freeform fabricating IPMC devices, and lays groundwork for further development of the materials and methods.

This work constitutes the first demonstration of complete, functional, IPMC actuators produced entirely by freeform fabrication.

Solid freeform fabrication (SFF) has the potential to revolutionize manufacturing, even to allow individuals to invent, customize, and manufacture goods cost‐effectively in their own homes. Commercial freeform fabrication systems – while successful in industrial settings – are costly, proprietary, and work with few, expensive, and proprietary materials, limiting the growth and advancement of the technology. The open‐source Fab@Home Project has been created to promote SFF technology by placing it in the hands of hobbyists, inventors, and artists in a form which is simple, cheap, and without restrictions on experimentation. This paper aims to examine this.

A simple, low‐cost, user modifiable freeform fabrication system has been designed, called the Fab@Home Model 1, and the designs, documentation, software, and source code have been published on a user‐editable “wiki” web site under the open‐source BSD License. Six systems have been built, and three of them given away to interested users in return for feedback on the system and contributions to the web site.

The Fab@Home Model 1 can build objects comprising multiple materials, with sub‐millimeter‐scale features, and overall dimensions larger than 20 cm. In its first six months of operation, the project has received more than 13 million web site hits, and media coverage by several international news and technology magazines, web sites, and programs. Model 1s are being used in a university engineering course, a Model 1 will be included in an exhibit on the history of plastics at the Science Museum London, UK, and kits can now be purchased commercially.

The ease of construction and operation of the Model 1 has not been well tested. The materials cost for construction (US$2,300) has prevented some interested people from building systems of their own.

The energetic public response to the Fab@Home project confirms the broad appeal of personal freeform fabrication technology. The diversity of interests and desired applications expressed by the public suggests that the open‐source approach to accelerating the expansion of SFF technology embodied in the Fab@Home project may well be successful.

Fab@Home is unique in its goal of popularizing and advancing SFF technology for its own sake. The RepRap project in the UK predates Fab@Home, but aims to build machines which can make most of their own parts. The two projects are complementary in many respects, and fruitful exchanges of ideas and designs between them are expected.

The paper's aim is to show the development of materials and methods which allow freeform fabrication of macroscopic Zn‐air electrochemical batteries. Freedom of geometric design may allow for new possibilities in performance optimization.

The authors have formulated battery materials which are compatible with solid freeform fabrication (SFF) while retaining electrochemical functionality. Using SFF processes, they have fabricated six Zn‐air cylindrical batteries and quantitatively characterized them and comparable commercial batteries. They analyze their performance in light of models from the literature and they also present SFF of a flexible two‐cell battery of unusual geometry.

Under continuous discharge to 0.25 V/cell with a 100 Ω load, the cylindrical cells have a specific energy and power density in the range of 40‐70 J/g and 0.4‐1 mW/cm², respectively, with a mass range of 8‐18 g. The commercial Zn‐air button cells tested produce 30‐750 J/g and 7‐9 mW/cm² under the same conditions, and have a mass range of 0.2‐2 g. The two‐cell, flexible Zn‐air battery produces a nominal 2.8 V, open‐circuit.

The freeform‐fabricated batteries have ∼10 percent of the normalized performance of the commercial batteries. High‐internal contact resistance, loss of electrolyte through evaporation, and inferior catalyst reagent quality are possible causes of inferior performance. Complicated material preparation and battery fabrication processes have limited the number of batteries fabricated and characterized, limiting the statistical significance of the results.

Performance enhancement will be necessary before the packaging efficiency and design freedom provided by freeform‐fabricated batteries will be of practical value.

The paper demonstrates a multi‐material SFF system, material formulations, and fabrication methods which together allow the fabrication of complete functional Zn‐air batteries. It provides the first quantitative characterization of completely freeform‐fabricated Zn‐air batteries and comparison to objective standards, and shows that highly unusual, functional battery designs incorporating flexibility, multiple cells, and unusual geometry may be freeform fabricated.

This paper reports on a fabrication platform and extensions to deposition‐based processes that permit freeform fabrication of three‐dimensional functional assemblies with embedded conductive wiring and power sources. Structure and joints are produced by fused deposition of thermoplastics and deposition of elastomers. Conductive wiring is achieved by deposition of various low‐melting‐point alloys and conductive pastes. Batteries based on zinc‐air chemistry are produced by the deposition of zinc, electrolyte, and catalysts, with separator media and electrodes. Details of the deposition processes are provided and several printed assemblies are demonstrated.

The paper aims to promote the development of intelligent materials and the 4D printing technology by introducing recent advances and applications of additive layered manufacturing (ALM) technology of intelligent materials and the development of the 4D printing technology. Also, an arm-type ALM technology of shape memory polymer (SMP) with thermosetting polyurethane is briefly introduced.

This paper begins with an overview of the development and applications of intelligent materials around the world and the 4D printing technology. Then, the authors provide a brief outline of their research on arm-type ALM technology of SMP with thermosetting polyurethane.

The paper provides the recent developments and applications of intelligent materials and 4D printing technology. Then, it is suggested that intelligent materials mixed with different functional materials will be developed, and these types of materials will be more suitable for 4D printing.

This paper overviews the current developments and applications of intelligent materials and its use in 4D printing technology, and briefly states the authors’ research on arm-type ALM technology of SMP with thermosetting polyurethane.

The study of the diffusion of innovations into libraries has become a cottage industry of sorts, as libraries have always provided a fascinating test-bed of nonprofit institutions attempting improvement through the use of new policies, practices, and assorted apparatus (Malinconico, 1997). For example, Paul Sturges (1996) has focused on the evolution of public library services over the course of 70 years across England, while Verna Pungitore (1995) presented the development of standardization of library planning policies in contemporary America. For the past several decades, however, the study of diffusion in libraries has tended to focus on the implementation of information technologies (e.g., Clayton, 1997; Tran, 2005; White, 2001) and their associated competencies (e.g., Marshall, 1990; Wildemuth, 1992), the improvements in performance associated with their use (e.g., Damanpour, 1985, 1988; Damanpour & Evan, 1984), and ways to manage resistance to technological changes within the library environment (e.g., Weiner, 2003).

A rapidly expanding number of organizations have begun to use high‐performance, completely digital networks, like the Internet, to coordinate activities and to develop products and services that serve very wide geographic areas. Now, primarily as a result of the Clinton Administration′s National Information Infrastructure initiative, the entire nation has begun to buzz with talk of the whys, wherefores, and how‐tos of making this way to doing business the rule rather than the exception of twenty‐first‐century life and enterprise. This paper surveys the politics and economics of the contemporary networking scene, and presents four general stratgies for making progress in the current climate of great change and uncertainty.

Addresses some of the key debates within the HRD literature and considers the extent to which HRD can be described as a field of study. The paper addresses the issues raised in the contributions that make up this special issue and identifies a broad range of methodologies and use of research methods. It argues that all of the contributions fit into at least one theoretical perspective: capabilities, psychological contacts and the learning organization/organizational learning. The paper concludes with a consideration of the prescriptions which the perspectives advocate for HRD in organizations.

The purpose of this paper is to integrate existing body of knowledge on evidence‐based management, develop a theory of evidence, and propose a model of evidence‐based decision making.

Following a literature review, the paper takes a conceptual approach toward developing a theory of evidence and a process model of decision making. Formal research propositions amplify both theory and model.

The paper suggests that decision making is at the heart of management practice. It underscores the importance of both research and experiential evidence for making professionally sound managerial decisions. It argues that the strength of evidence is a function of its rigor and relevance manifested by methodological fit, relevance to the context, transparency of its findings, replicability of the evidence, and the degree of consensus within the decision community. A multi‐stage mixed level model of evidence‐based decision making is proposed with suggestions for future research.

An explicit, formal, and systematic collaboration at the global level among the producers of evidence and its users akin to the Cochrane Collaboration will ensure sound evidence, contribute to decision quality, and enable professionalization of management practice.

The unique value contribution of this paper comes from a critical review of the evidence‐based management literature, the articulation of a formal theory of evidence, and the development of a model for decision making driven by the theory of evidence.

The purpose of this paper is to identify relevant gaps in human capital (HC) related to innovation performance, which might be the basis for creation of more effective innovation strategies.

The proposed approach contains the following four steps: HC survey, assessment of HC value drivers, identification of gaps related to the HC value drivers and recommendations for an innovation strategy based on identified gaps. The HC survey includes 554 managers from Serbian companies within seven different industries.

The biggest gaps in observed Serbian industries are related to crucial HC value drivers for innovation process, such as innovativeness, education and knowledge sharing and social skills.

Although there are limitations in measuring HC and innovation drivers, this approach seems to be valid in recommending more effective innovation strategies/policies on micro and macro level.

This research reveals potentials and barriers within HC in different Serbian industries, crucial to innovation, pointing to the initiatives which might improve innovation performance across Serbian industries. The identification of HC gaps across industries is valuable for gathering sounder intelligence of the sources of innovation and fine-tuning of national innovation strategy according to specific features of industries.

The proposed approach integrates a new perspective into current innovation measurement paradigm. It includes gaps within HC in the assessment of innovation performance, which might foster intangible innovation potential.