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Fused deposition of ceramics (FDC) is a solid freeform fabrication technique based on extrusion of highly loaded polymer systems. The process utilizes particle loaded thermoplastic binder feedstock in the form of a filament. The filament acts as both the piston driving the extrusion and also the feedstock being deposited. Filaments can fail during FDC via buckling, when the extrusion pressure needed is higher than the critical buckling load that the filament can support. Compressive elastic modulus determines the load carrying ability of the filament and the viscosity determines the resistance to extrusion (or extrusion pressure). A methodology for characterizing the compressive mechanical properties of FDC filament feedstocks has been developed. It was found that feedstock materials with a ratio (E/η_a) greater than a critical value (3×10⁵ to 5×10⁵ s^‐1) do not buckle during FDC while those with a ratio less than this range buckle.

There is progress in entrepreneurship research. Important works in entrepreneurship increasingly appear in highly respected, mainstream journals (see Busenitz et al., 2003; Davidsson, Low & Wright, 2001). There is conceptual development that attracts attention (e.g. Shane & Venkataraman, 2000) and handbooks are compiled, providing the field with more of a common body of knowledge (Acs & Audretsch, 2003a; Shane, 2000a; Westhead & Wright, 2000). Further, there is evidence of methodological improvements (Chandler & Lyon, 2001) and accumulation of meaningful findings on various levels of analysis (Davidsson & Wiklund, 2001). Moreover, due to time lags in publication the reported improvements are likely to be underestimated. This author’s experience as organizer, reviewer and participant in core entrepreneurship conferences on both sides of the Atlantic (e.g. Babson; RENT) suggests that much of the lower end of the quality distribution has either disappeared from the submissions or is screened out in the review process. Much more than used to be the case a few years back we find among the presented papers research that is truly theory-driven; research on the earliest stages of business development, and research that employs methods suitable for causal inference, i.e. experiments and longitudinal designs.

To fabricate high quality parts, and to make the development generic yet compatible with the in‐house hardware, a virtual simulation system has been developed, and an in‐house intelligent multi‐material toolpath generation system has been under development. This new development includes the issues such as multiple fill‐toolpaths for the same material, interface mismatch between adjacent materials and the intelligent toolpath features for machine control. After the multi‐material toolpath file generated by the in‐house software, the existing virtual graphical simulation as well as well selected part fabrication experiments were used to validate it. Based on the authors’ ongoing research about multi‐material layered manufacturing, it was determined that the build characteristic was heavily dependent on the material being used. Therefore, it was important to develop the hardware/software that will accommodate this requirement.

The purpose of this paper is to systematically and critically review the literature related to process design and modeling of fused deposition modeling (FDM) and similar extrusion-based additive manufacturing (AM) or rapid prototyping processes.

A systematic review of the literature focusing on process design and mathematical process modeling was carried out.

FDM and similar processes are among the most widely used rapid prototyping processes with growing application in finished part manufacturing. Key elements of the typical processes, including the material feed mechanism, liquefier and print nozzle; the build surface and environment; and approaches to part finishing are described. Approaches to estimating the motor torque and power required to achieve a desired filament feed rate are presented. Models of required heat flux, shear on the melt and pressure drop in the liquefier are reviewed. On leaving the print nozzle, die swelling and bead cooling are considered. Approaches to modeling the spread of a deposited road of material and the bonding of polymer roads to one another are also reviewed.

To date, no other systematic review of process design and modeling research related to melt extrusion AM has been published. Understanding and improving process models will be key to improving system process controls, as well as enabling the development of advanced engineering material feedstocks for FDM processes.

Fused‐deposition (FD) is a robotically controlled “fiber” extrusion process that produces a new class of materials with a variety of controllable mesostructural features related to fiber layout and the presence of voids. Mesostructural features of importance to the stiffness and strength of unidirectionally extruded materials were characterized as a function of the processing variables. Samples were made using the Stratasys FDM1600 Modeler with the P400 acrylonitrile‐butadiene‐styrene plastic. Results showed that the void geometry/density and the extent of bonding between contiguous fibers depended strongly on the fiber gap and extrusion flow rate. Settings for minimum void and maximum fiber‐to‐fiber bonding were determined. Void and bond length densities in the plane transverse to the fiber extrusion direction varied from 4 to 16 per cent and 39 to 73 per cent respectively. The results quantify the important mesostructural features as a function of the FD process variables and are expected to find use with other FD materials.

In “The next wave of entrepreneurship research,” Schoonhoven and Romanelli (hereafter S&R, this volume) set forth a broad-gauge review of recent work in entrepreneurship. They challenge standard debates and focus on arguments and research that explore large-scale contextual variation in complex ecologies of entrepreneurship over time. Further, their review puts networks and teams, communities of expertise and knowledge, and collective activity at the center of new directions for entrepreneurial research. They contend, in this paper and elsewhere, that the important questions going forward “concern the mass effects of entrepreneurial activity on the creation of new firms and industries, the pioneering of emerging markets, the evolution of existing industries, the development of regional economies, and even … the competitiveness of nations” (Schoonhoven & Romanelli, 2001, p. 383).

Many researchers and executives have viewed fit as a key to organizational survival and high performance (Summer et al., 1990). However, the type of fit and how it can be best achieved may often be in question (Venkataraman, 1989). The current study empirically examines both external and internal fit as predictors of firm performance where: (1) external fit is the alignment of, or congruence between, the organization's strategy and/or structure and the task environment, and (2) internal fit is the multidimensional matching of strategy with structure. The argument presented here is that both internal and external fit can, and do, occur simultaneously. Further, the presence of one type of fit may compensate for deficiencies in the other. Using fit in terms of both matching and moderation, hypotheses are tested to determine the nature of both internal and external fit of strategy and structure. Testing of the hypotheses is conducted using data from the medical group industry. Findings support the influence of individual strategy and structure variables on medical group performance. However, fit found between strategy and structure, be it as matching or moderation, shows little influence on performance. Implications for medical groups and the broader health care industry are discussed.

Despite the huge amount of studies that have investigated the strategy–performance relationships and knowledge management (KM)–performance relationships, there is little consensus regarding the nature of these connections. By reviewing related literature, some notable limitations and inconsistent results are highlighted in extant studies. To address these challenges, this study aims to explore the effects of strategic orientation and KM mechanisms on business performance.

The study conducted an empirical investigation of 227 small- and medium-sized enterprises (SMEs) to explore the relationship between strategy−performance and KM−performance. Business strategy is conceptualized as a comparative construct with six dimensions, KM is conceptualized by two types of KM mechanisms of technical and non-technical KM mechanisms and business performance is measured by four dimensions of balanced scorecard (BSC). The cluster analysis was used to explore different aspects of these three constructs.

Using cluster analysis, the results indicate that firms with high level of analysis, defensiveness, futurity and proactiveness in strategic orientation have better performance and also the high level of both KM mechanisms another important finding shows that firms with more KM mechanisms have high performance and technical mechanisms have more predictor role on performance.

This research also has prescriptive implications for strategic managers and KM practitioners. The finding enhanced the understanding of the relationship between strategic orientations, KM and performance. The results assist managers to assess business performance regarding strategic orientations and KM mechanisms of the firms. Therefore, it helps firms to improve strategic resource allocation and exploit KM investment by considering ideal pattern of the performance.

By reviewing strategic management and KM literature, it is revealed that there are little studies about how the interaction of strategic orientation and KM influences business performance. The main contribution of the study is exploring the profile of the firms by considering their strategic orientation and KM mechanisms and their impact on business performance. This study provides an empirical evidence about interaction of strategic orientations, KM mechanisms and business performance in SME context, which is merely investigated in previous researches.

Numerous empirical investigations have attempted to study the relationship between multinationality and firm performance. Results from these studies have produced conflicting findings about this relationship. We argue that one of the causes of the conflicting findings may be an imprecise conceptualization of multinationality. We propose a multidimensional conceptualization based on a methodological review of previous research.