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51.
根据双臂电桥原理搭建出实验电路进行数据采集,再应用贝叶斯频谱估计算法对测得的数据进行分析,得出反射频率周期,然后根据反射原理推算出人工传输线的长度。由于在检测方法和分析方法上的改进,在传输线长度的测量精度上获得了很好的效果。在实验中,根据先验知识和理论得出一个特定的模型方程;在实际应用中如果能够找到一个合适的模型方程,那么就可以运用贝叶斯频谱估计方法进行分析,因此贝叶斯频谱估计算法有着非常广泛的实用价值。  相似文献   
52.
We define ethical system infrastructure as being composed of three major factors – means, motivation, and opportunity. Means are defined as organizational rules, policies, and procedures. Motivation focuses upon the values and the interests being pursued by the position occupant and the organizational value system, while opportunity is discussed in terms of the environment in which the dilemma occurs, proposing that position in the hierarchy presents its own unique set of ethical dilemmas. Ethical breeches are discussed in terms of the interactional processes among means, motivation, and opportunity. Finally, a sequential process is suggested to use the infrastructural components to institutionalize organizational ethics training and subsequent behavior.  相似文献   
53.
Innovation requires the entrepreneurial capabilities of opportunity recognition and opportunity exploitation. Such capabilities generally accrue over time from a firm's cumulative learning and experience. In this study, we theorize that firm age should therefore moderate the firm's ability to leverage these capabilities for innovation activity, such that older firms can obtain higher outputs from their capabilities than younger firms can. We examine this relationship using a sample of 676 small and medium enterprises. We find that when both younger and older firms have highly developed innovation capabilities, older firms appear to enjoy higher levels of innovation activity than younger firms do. However, younger firms generally appear more likely to have higher levels of innovation activity than older firms do, when neither firm has highly developed innovation capabilities. We conclude with a discussion of the implications of these findings for research and practice.  相似文献   
54.
A bstract . Instrumentalism and the instrumental logic , as developed and reconstructed by John Dewey, Clarence Ayres , and Jacob Bronowski , is a mode of philosophy exceedingly critical of dualistic, teleological, tautological, and atomistic individualistic biases in philosophy and in economic theory. Instead, it has emphasized processual, contextual, and evolutionary systems of analysis, accentuating conceptual linkages, topological connectivity and joint relationships as a basis of rejecting conceptions of scientific neutrality and intellectual "instruments" forged in an insulating and compartmentalizing style. The principle of continuity becomes the key to the truth process and its directly associated theory of instrumental value. Applying this instrumental philosophy to the critical analysis of the utility theory of value underpinning orthodox economic theory not only exposes the theoretical and philosophical failures of the utility approach but also highlights the strengths of the instrumental logic as a reconstructive tool. The "life process of mankind" is most enhanced by distinguishing truth from falsity and by applying warranted knowledge to the examination of social and economic problems and the power institutions which give them an exacerbated life.  相似文献   
55.
Abstract . ‘Savages,’ as Europeans considered the Americans of ancient times, never built the great Mayan centers. The builders of great cities in Meso-America were a well-organized group with an adequate land base and a rather sophisticated technology. From 300 B.C. to 900 A.D. the Maya developed and perfected an agriculture-based economy with a well developed commerce, writing, art, science, religion and government, as well as an advanced architecture of monuments, palaces, temples and pyramids. Their civilization reached intellectual heights unique in the Western Hemisphere. What conditions caused its decline and fall? Interpreting the geographic and historical record in the light of the relevant social sciences, one can say a complex of circumstances: ecological abuse, exploitation of the working population, mismanagement, militarism, bad weather, famines, and epidemics.  相似文献   
56.
In conducting a longitudinal examination of eight long-term complex decision processes in two Fortune 500 heavy manufacturing companies the authors developed a six-level framework of decision complexity. The levels range from: (1) instantaneous decision choices to (2) decision actions (3) decision events (4) mini-decision processes (5) decision processes and (6) decision theatres. They vary in time, numbers of participants, and in the integrative effort required to formulate and implement them. Thus, one problem with the word ‘decision’is that it is used to mean many different things in organizational settings. Each lower level of ‘decision’was found to combine with ‘decisions’of the same level and to be embedded within higher levels, resulting in a nested hierarchy of simultaneously occurring processes.  相似文献   
57.
58.
Transport infrastructure is an important subsector within infrastructure, but knowledge of its equities in terms of risk-return characteristics and contribution to portfolio performance is still limited. This study assesses the subsector individually and in a multi-asset, index-based portfolio. In doing so, we apply a t-Copula-based Conditional Value-at-Risk model to simulate risk and returns. Our findings reveal that the subsector has a relatively low dependency on other equities, performs like other alternative asset classes such as general real estate, and does not grant significant risk diversification benefits for mainstream institutional investors such as pension funds. Investors aiming for higher target returns may however assign substantial weights to transport infrastructure, supporting our conjecture that it does not share the same asset class characteristics as general infrastructure. By contrasting Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR) scores for both the mean-variance framework and the t-Copula simulation, we further document the limitations of traditional VaR approaches. Hence, this study’s results support the use of risk assessment tools that incorporate non-normal distributions to represent multivariate dependence structures.  相似文献   
59.
This paper investigates changes in factors bearing on technology adoption decisions in small manufacturing firms. It is hypothesized that, as a firm's experience with technology increases and its technological capabilities grow, the decision process is gradually modified and puts more weight on those factors which are more closely related to the true potential of the technology. An empirical study shows the more innovative firms to have an outward orientation dominated by clients and suppliers, and to pay more attention to the added flexibility brought about by new technology. It is also shown that functional groups within the company play a more important role in the decision-making process.  相似文献   
60.
The paper analyzes empirical evidence from 368 environmentally responsive small and medium-sized enterprises (SMEs) operating in four industries. The results demonstrate that firms' environmental performance cannot be viewed as a one-dimensional concept and that determinants of firms' environmental performance depend on the dimension retained. The impacts of firms' environmental performance on their innovativeness and competitiveness vary according to the industry within which they operate. However, impacts on product and process innovations as well as on managerial innovations are positive and significant in all four industries.  相似文献   
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