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Summary The objective of the present study was to determine whether golf clubs that have titanium (Ti) alloy surfaces can produce sparks when abraded under normal swing conditions. In the present work, sparks are defined as moving particles that emit radiant energy due to the process of combustion on its surface. Two three-irons and a three-wood containing a Ti alloy in the head as well as two three-irons and a three-wood that only contain stainless steel in the head were included in the study. The impact events during abrasion testing were recorded using a high-speed video camera, and abrasion damage was determined using stereometric analysis of scanning electron microscopy images. The findings reveal that Ti alloy faceplates that extend to the sole of the club can produce a number of Ti alloy particles when abraded under swing conditions. The particles then combust for a sufficient duration to potentially ignite a neighboring fuel source such as dry foliage and grasses. Abraded Ti alloy microparticles up to 500 µm in diameter were observed to burn for nearly 1 s, allowing ample time for fuel ignition. By contrast, no sparks were produced by stainless steel club heads when tested under the same conditions. Copyright © 2014 John Wiley & Sons, Ltd.

This article presents a microstrip-fed slot-aperture hybrid antenna for wideband circularly polarized (CP) operations. The antenna consists of a U-shaped slot, a rectangular aperture, and a probing strip fed by a microstrip line. In general, the U-shaped slot and the rectangular aperture resonate at two separate frequencies. When properly arranged, the proposed antenna may resonate over a single wideband of CP radiation. The 3-dB axial ratio (AR) bandwidth of the presented antenna in free space is about 27% with the gain level about 34 dBic. When a planar reflector is incorporated for the desirable unidirectional pattern, the presented antenna has an enhanced gain about 7 dBic with a 3-dB AR bandwidth of 25% and a front-to-back ratio of about 14 dB. Good agreement between measured and simulated results was achieved. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:412–415, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26569

Theoretically and empirically, the linkage between outside directors and firm performance is not conclusive in previous studies. We suspect that the mixed results are due to the failure to meet the requirements of the independence of outside directors. As the Taiwanese government has a rigorous definition of outside director independence, we employ a data set from Taiwan to test the impact of independent outside director assignment on a firm's performance. Our findings suggest that after controlling for a firm's past performance, independent outside director appointments do have a significantly positive impact on a firm's performance, and outperforming firms may have better performance but not significantly when assigning outside directors due to their absorptive capacity.

The aim of this study is to foster an understanding of the clinical characteristics, in terms of general psychopathology, of Tourette syndrome (TS), as it manifests in adolescent patients, and to compare these results with those of previous studies conducted in Western countries. In total, 38 male and 5 female adolescent patients who visited a pediatric neurological specialty clinic for TS between 1 January and 1 March 2003, and who met the World Health Organisation criteria for TS, were studied. These patients were clinically interviewed and assessed with the Symptom-Checklist-90-R, Family APGAR and Tic Symptoms questionnaire, a self-report questionnaire based on DSM-IV TS diagnostic criteria. Among this population, the mean age of onset of motor tics was 9.65 +/- 3.7 years, and motor tics of the head and eyes were usually the first symptoms to manifest; coprolalia occurred in 44.1% (n = 19) of our patients. Many of our findings were similar to those reported in trials conducted in other regions of the world. TS symptoms showed stronger correlation with emotional distress in older patients.

Immunodeficiency occurs in numerous genetic syndromes. While it is the dominant manifestation in primary immunodeficiencies, immune deficits may also be seen in a variety of other recognizable syndromes. Immunodeficiency has been reported in 64 such conditions, adding to the 45 recognized primary immunodeficiencies. These uncommon syndromes with immune defects can present with: (a) growth deficiency (11 syndromes with disproportionate or proportionate short stature), (b) specific organ system dysfunction (18 with gastrointestinal, dermatologic, or neurologic abnormalities), (c) inborn errors of metabolism (13), (d) miscellaneous anomalies (10), or (e) chromosome anomalies (12). In most of the disorders, only some of the affected patients have immune defects. However, in 27 syndromes, immunodeficiency is a constant finding. We briefly review the clinical manifestations of each syndrome and delineate the specific associated immune defects. In most syndromes, the connection between the immune and other defects is unknown. Recognition of these conditions involving both the immune and other organ systems may facilitate accurate diagnosis and management as well as yield information regarding genes critical for the development of the involved systems.

This article identifies key features of the strategy concept as a basis for reviewing existing theories of strategy. It also provides an agenda for future research. the article argues that there is a decision hierarchy in a firm, and defines strategy as the highest-level decision in the hierarchy. Consequently, strategy has to exhibit what may be called three features of dominance: vertical dominance, horizontal dominance, and dynamic dominance. A vertically dominant strategy is one that determines, directly or indirectly, other decisions of a firm. A horizontally dominant strategy seeks to optimize the value of the firm according to some criteria. Dynamic dominance implies that strategy should affect the subsequent decisions of a firm over a relevant period of time. With few exceptions, existing theories of strategy are issue-oriented and focus largely on horizontal dominance. More research should, therefore, be directed towards vertical and dynamic dominance criteria. If a comprehensive theory of strategy which satisfies the three dominance features cannot be developed, it is suggested that development should be directed towards integrating behavioural and economic approaches.

Despite the fact that a great deal of empirical research confirms the existence of strategic groups, not enough attention has been paid to their theoretical development. This paper links the theories of spatial competition and cognitive taxonomy to the very existence of strategic groups in a competitive environment. It is shown that the concept of strategic groups is not an analytical convenience but a theoretical construct.

This paper constructs models to investigate the rationale for a multinational corporation to enter into a joint venture to serve a host market. In particular, the model examines the impact of profit sharing, cost reductions, risk reductions, and competition reductions on the profits of international joint ventures. The results may explain the ‘recent’ popularity of international joint ventures. The models show that (1) a joint venture is the dominant entry strategy when there is a formidable local competitor and the risks of operation are high, (2) a wholly owned subsidiary is preferred if a multinational corporation has a significant cost advantage, (3) a joint venture is preferred to a wholly owned subsidiary if significant cost reductions can be achieved through combining the strengths of a multinational corporation and a local firm, and (4) multiple licensing is preferred if the number of local firms is large.

This paper examines competition patterns and competitive strategies when technology changes continually. It first discusses optimal behavior for investment in technology. It is argued that although technological innovations supersede existing technologies, there are economically justifiable barriers to investing in the new technologies. These economic barriers, coupled with continuous technological change, have implications for certain aspects of strategy, such as entry by means of new technologies, timing of entry, leapfrog-type competition, vertical integration, the productivity dilemma, and escalating commitment. Finally, the industrial transformation of the steel industry is used as an example to illustrate these implications.

This paper highlights the significance of escalating commitment to strategy formulation, briefly examines behavioral explanations of escalating commitment to a losing course of action, and finally proposes an economic theory of the escalating commitment phenomenon. An example of escalating commitment to an outdated technology is presented. It is shown mathematically that there are economic justifications for escalating commitment to a failing strategy. Strategic implications for the first move advantage and for the U.S. steel, auto and semiconductor industries are discussed.