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131.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2005 Benjamin Franklin medal in physics to Yoichiro Nambu for his seminal contributions which introduced the modern concept of broken symmetry to elementary particle physics, for his invention of the particle property called color which is the key to quark confinement, and for his ground-breaking work on the theory of string-like elementary particles.  相似文献   
132.
Characterizing the technology firm: An exploratory study   总被引:1,自引:0,他引:1  
Technology firms occupy a central position in modern economies. They drive economic growth, productivity gains and have created new industries and innovative products.Many will agree that technology firms are distinguished from others in their emphasis on technological activities. Since this observation is too general, researchers suggested a variety of specific criteria and definitions. A number of definitions of technology firms appear in the literature but many are arbitrary and simplistic and none gained wide acceptance. Similarly, the number of characteristics suggested is large, reflecting a variety of perspectives and interests. In this case too no agreement exists as to which are the important ones. Also, many seem to be interrelated capturing different aspects of the same underlying concepts.This paper is concerned with the issue of definition and classification of technology firms. We demonstrate the usefulness of a different approach to the definition and classification problem. We rely on executives’ evaluations of their firms’ technology profile and level. An analysis of these evaluations reveals the underlying dimensions the executives used in making their judgments. We regard the dimensions we uncover as capturing the essence of technology firms and use them to classify the firms we study. The specific characteristics the executives used to evaluate their firms were derived from a systematic scan of the literature. Thus, the list represents the set of characteristics early researchers viewed as describing and defining technology firms. The connection to early work enhances our findings’ validity and lends some credence to our belief that the three dimensions we uncover (R&D activities which are closely associated with a set of organizational elements and market conditions, product strategy, and corporate culture) can be used by others to define technology firms and classify firms according to their technology level. In our study we use these three dimensions to classify the firms studied. We show that the commonly used practice of classifying firms as high and low technology according to the industry to which they belong is flawed.Our goal in this study is not to offer a “new” or “better” definition and characterization of technology firms or to offer the “best” approach to the generation of the classification criteria. Rather, we demonstrate here the usefulness of a different approach to the problem. While our approach does suffer from limitations it has important advantages. We hope future studies will confirm not only the usefulness of our approach but also the general applicability of the specific criteria we identify in this study.  相似文献   
133.
This paper presents findings of a study conducted to evaluate the extent to which the Agricultural Information Service (AIS) is providing agricultural information services to farmers in Maseru district, Lesotho.  相似文献   
134.
In this paper, an optimum grounding grid that provides the conditions of GPR<Etouch and minimum cost in the structures of two-layer soil model is designed and the length of total conductor and the quantity of ground rod are calculated via Genetic Algorithms (GA). A new approach is presented for the calculation of total conductor length. At the same time, the subject regarding in which layer the ground conductors and rods that form the grounding grid in a substation are to be placed in two-layer soil is analysed using GA. With this as the goal, the depth of optimum grid burial is determined. Our study is compared with the design study for a two-layer soil model in the literature. As a result, the high performance of optimum grid design that is achieved using GA is emphasized by varied applications.  相似文献   
135.
In this paper, we illustrate the development of a realistic simulation of a humanoid robot model in a virtual environment using USARSim (Urban Search and Rescue Simulator). USARSim provides an accurate 3D simulation of a virtual environment with a detailed rendering and a realistic physics. Moreover, USARSim allows users to observe the virtual environment from different views. One of these is the egocentric view, which can simulate the camera mounted on the robot. The small humanoid robot presented in this work is Robovie-M, developed by VStone Ltd. (Japan). This robot is used by our team Artisti in the RobotCup soccer competitions.Reported experiments compare the behaviors of a real robot and of its virtual model, when controlled by the same control software to asses the possibility to faithfully simulate a robot with 22 degrees of freedom in USARSim. Moreover, we discuss the possibility to close the control loop of the robot in simulation, by simulating also the main robot sensor, i.e. the camera.The experiments show that USARSim, despite being a simple simulator based on a low cost computer game, provides an accurate enough simulation of the physics and a realistic rendering of the 3D scene enabling a faithful simulation of a small humanoid robot at low cost. Thus, one can entirely test the robot software modules in the simulation (namely: the motion control modules, the vision system modules and, by closing the robot control loop in simulation, the behavior and behavior-selection modules).  相似文献   
136.
采用主动式气体采样、2,4-DNPH二硝基苯肼吸收、高效液相色谱(HPLC)分析研究了西安市冬、夏两季三所普通居民住宅室内、外空气中13种醛酮类化合物。结果表明:冬、夏两季西安地区住宅室内空气中醛酮类污染物浓度水平均较高。其中,夏季室内、外空气中13种醛酮类化合物总质量浓度为85.86±30.33 µg&#8226;m-3和78.86±31.40 µg&#8226;m-3,冬季为85.40±28.50 µg&#8226;m-3和53.77±16.39 µg&#8226;m-3;室内均高于室外;甲醛、乙醛、丙酮为最高组分,三者为总质量的75~80%;三所住宅中,2号住宅(H2)醛类污染物严重,表明装修材料(木地板)与吸烟均有一定程度贡献。  相似文献   
137.
There is much debate among scholars about what constitutes e-government success, what method is best for measuring it, and which variables best describe it. This lack of consensus naturally leads to disagreement about the best approach for ranking the e-government programs of different countries. This article evaluates the current standard in e-government ranking, the United Nations E-government Development Index, by performing a confirmatory factor analysis on the raw data reported in the “Data tables” section of the “Statistical annex” in the 2010 United Nations E-Government Survey. The results identify several technical issues with the index and point to the need for a statistical tool that can be used to evaluate and guide the development of e-government ranking systems. The article recommends that researchers develop a new paradigm for quantitative e-government ranking that uses factor analysis to aid in the selection of variables, the organization of aggregate constructs, and the determination of weights.  相似文献   
138.
This study examines channel choice and public service delivery in Canada, comparing e-government to traditional service delivery channels such as the phone or visiting a government office. Factors studied include the digital divide, the nature of the citizen interaction with government, public service values, and satisfaction with services received by citizens. These factors are used to determine whether they impacted choice of channel and satisfaction with that channel. This study, through logistic regression of a public opinion survey of Canadian residents, found indications suggesting a digital divide in accessing e-government; found that government websites were most commonly used for information purposes, while the phone was most commonly used to solve problems. In regards to citizens' satisfaction, the apparent digital divide was bridged when females and older Canadians were more satisfied with their contact with a government website. In addition, a positive experience with service delivery and positive public service values lead to greater website satisfaction. The results of this study imply that the phone is a more effective service channel for solving problems, and the website is more effective for getting information. Therefore, governments need to provide multiple contact channels for citizens, depending upon their task at hand, while ensuring consistency of information and service response across channels. Creating a positive experience for citizens when they received a service translates into a more satisfied experience with e-government.  相似文献   
139.
Through various platforms enabled by Web 2.0 technologies, citizens can collectively create public information, provide service, and take part in policy processes. Pushed by the Open Government Directive of the Obama administration, citizen-sourcing may be a new mode of government operations in the U.S. This paper suggests two frameworks to examine the emerging mechanism. The first framework provides three dimensions of citizen-sourcing initiatives: purpose (image-making or ideation), collective intelligence type (professional knowledge or innovative ideas), and strategy (contest, wiki, social networking, or social voting). Second, the paper presents a framework for assessing current citizen-sourcing initiatives. Its categories include design evaluation, process evaluation, and outcome evaluation. The performance of citizen-sourcing primarily depends on the appropriateness of the platform design. The effectiveness of the process needs to be evaluated in terms of the Open Government Directive's three pillar goals of transparency, participation, and collaboration. Evaluating the impact of citizen-sourcing will reveal whether citizen-sourcing is rhetorical or if it actually exerts significant effects on society.  相似文献   
140.
In the second half of the 20th century, scientific research in physics, chemistry, and engineering began to focus on the use of large government-funded laboratories. This shift toward so-called big science also brought about a concomitant change in scientific work itself, with a sustained trend toward the use of highly specialized scientific teams, elevating the role of team characteristics on scientific outputs. The actual impact of scientific knowledge is commonly measured by how often peer-reviewed publications are, in turn, cited by other researchers. Therefore, how characteristics such as author team seniority, affiliation diversity, and size affect the overall impact of team publications was examined. Citation information and author demographics were reviewed for 123 articles published in Physical Review Letters from 2004 to 2006 and written by 476 scientists who used the National High Magnetic Field Laboratory's facilities. Correlation analysis indicated that author teams that were more multi-institutional and had homogeneous seniority tended to have more senior scientists. In addition, the analysis suggests that more mixed seniority author teams were likely to be less institutionally dispersed. Quantile regression was used to examine the relationships between author-team characteristics and publication impact. The analysis indicated that both weighted average seniority and average seniority had a negative relationship with the number of citations the publication received. Furthermore, the analysis also showed a positive relationship between first-author seniority and the number of citations, and a negative relationship between the number of authors and the number of citations.  相似文献   
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