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1.
Abstract. Information technology is becoming an increasingly important factor in contemporary management. Information systems are being set up in business explicitly to accommodate the new opportunities of this technology, and these are having a lasting effect on managerial practice. The full implications of this technology-driven development have not been appreciated by organizations, which in absorbing technological systems, are tolerating a great drain on their resources.
The efficacy of computers is predicated on the acceptance of some very specific perspectives. A growing discontent and disappointment with their limited achievements is our reason for advocating a different point of view. We will discuss how a shift in perspective, particularly in respect to the perception of uncertainty, will affect thinking and practice in the field of management support systems. We will render our view of the application of computerized decision support systems (DSS), and especially, we will focus on the beliefs and assumptions that have shaped this technology thus far. To this end we will discuss the concept of uncertainty, by juxtaposing current thinking and practice with our understanding of the context of its application. Finally, we will place our understanding of uncertainty in a managerial context and explain the implications this would have for strategists.  相似文献   
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The case is described of a 58 year old man with systemic Whipple's disease with pericardial and pleural effusions and severe pulmonary hypertension. After three months of antibiotic treatment there was a complete resolution, not only of the symptoms known to be associated with Whipple's disease (diarrhoea, arthralgia, pericardial and pleural effusions), but also of pulmonary hypertension.  相似文献   
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The specific heat at constant volume cv shows a weak singularity at the critical point. Renormalization group techniques have been applied, predicting a universal critical behavior which has to be experimentally confirmed for different systems. In this paper an experiment is presented to measure the specific heat of SF6 along the critical isochore (c=0.737 g·cm–3), applying a continuous heating method. The results cover a temperature span of –1.5×10–2< <1.70×10–2 [=(TT c)/T c] and were strongly affected by gravity effects that emerge in the sample of 1-mm hydrostatic height near the critical point. Using regression analysis, data were fitted with functions of the form c v/R=A × ¦¦ + B for the one-phase state and c v/R=A × ¦¦ + B for the twophase state. Within their error bounds the critical values (==0.098, A/A=1.83) represent the measurements for the temperature span 3.5×10–5< ¦¦<2.0×10 –3, in good agreement with theoretical predictions. In order to exclude density profiles in the specimen, which are unavoidable in terrestrial experiments due to the high compressibility of fluids at the critical point and the gravity force, a space-qualified scanning ratio calorimeter has been constructed, which will permit long-term cv measurements under microgravity (-g) conditions. The experiment will be part of the German Spacelab mission in October 1985. The significant features of the apparatus are briefly sketched.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A.  相似文献   
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Dynamic light scattering is a suitable method for the investigation of transport properties such as the thermal diffusivity of optically transparent fluids. The main advantages of the method are its quickness, the fact of the thermodynamic state of equilibrium of the sample (gradients are not required), and the relatively simple evaluation of data without the necessity of calibration. However, an insufficient production of intensity of scattered light may be a limiting effect. For that reason the vicinity of the gas-liquid critical point represents the classical range of application. In this paper, it is shown that by means of an appropriate choice of experimental apparatus, measurements are also feasible in an extended range of states. Broad regions around critical points of three pure fluids (sulfur hexafluoride, SF6; ethane, C2H6; nitrous oxide, N2O) over temperature ranges ¦T-T c¦ of 0.02 to 50 K and density ranges (/c) of 0.2 to 2 were investigated. In this region the thermal diffusivity shows great variations with temperature and density and cannot be described by means of ideal-gas behavior or relations for liquids. The measurements were carried out along the coexistence curve for both phases, along the critical isochore and along some isotherms with TT c. The measured or calculated density, pressure, and thermal diffusivity data as well as some correlations are presented.  相似文献   
6.
While most research on website has focused on functional tasks, the Internet offers many opportunities for leisure as well as experiential activities. Because of the evolution of developed society toward an experience economy, analyzing the role of technologies in the presence of prior user experiences makes sense. This research identifies variables that play a role and influence online behaviors in a specific experiential environment, namely the high culture museum website. Relying on the literature on experience, we propose a research model tested with two different websites. The results of the free simulation experiment indicates that (1) esthetics is the most important design criteria for experiential interfaces and (2) that website design influences intentions to visit a physical place.  相似文献   
7.
Eosinophils (EOSs) are granular leukocytes that have significant roles in many inflammatory and immunoregulatory responses, especially asthma and allergic diseases. We have undertaken a fairly comprehensive proteomic analysis of purified peripheral blood EOSs from normal human donors primarily employing 2‐DE with protein spot identification by MALDI‐MS. Protein subfractionation methods employed included IEF (Zoom® Fractionator) and subcellular fractionation using differential protein solubilization. We have identified 3141 proteins, which had Mascot expectation scores of 10?3 or less. Of these 426 were unique and non‐redundant of which 231 were novel proteins not previously reported to occur in EOSs. Ingenuity Pathway Analysis showed that some 70% of the non‐redundant proteins could be subdivided into categories that are clearly related to currently known EOS biological activities. Cytoskeletal and associated proteins predominated among the proteins identified. Extensive protein posttranslational modifications were evident, many of which have not been previously reported that reflected the dynamic character of the EOS. This data set of eosinophilic proteins will prove valuable in comparative studies of disease versus normal states and for studies of gender differences and polymorphic variation among individuals.  相似文献   
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During the Second German Spacelab Mission D2 (April 26 to May 6, 1993) the isochoric specific heatc v of SF6 was measured along the critical isochore under microgravity conditions with a newly developed scanning radiation calorimeter. This calorimeter provided the possibility to perform comparable heating and cooling runs with variable ramp rates since the spherical sample cell was heated and cooled only by radiation. During the experimental time of 220 h, 11 heating and cooling runs with different ramp rates were performed in a temperature range ofT–T c=±6 K. ApproachingT c by cooling from the homogeneous one-phase region avoided significant temperature and density gradients in the fluid, which would have distorted the integral measurement ofc v. The inhomogenities introduced by a finite ramp rate were greatly reduced by the fast dynamic temperature propagation (critical speeding up). Thec v data achieved with slow cooling runs are in remarkably good agreement with the theoretical prediction more than one order of magnitude closer to the critical point than anyc v measurements done so far. The preliminary value for the critical exponent is 0.107±0.02, and for the amplitude ratio we obtainedA /A +=1.94±0.07. In contrast to the cooling runs, the heating runs showed a strong hysteresis ofc v. A comparison to 1g measurements is provided.Invited paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, USA.  相似文献   
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Using resource dependency theory (RDT), this research analyzes how organizations control their information technology resources to improve organizational performance. According to RDT, organizations must manage their dependency on external organizations and limit external dependencies when resources are considered critical. The current study proposes and tests a portion of a Strategic Control Model positing that managers seek to control important, strategic resources in order to create value for the firm and to avoid dependency on external entities. Utilizing a research design that captured extensive quantitative data on the control of IT functions and services, the research team gathered 5 years of data on 54 business units (BUs) in 27 global companies located in seven countries. Study examined the linkages of these 54 BUs to firm performance. Locating the Extent of Control within the firm in cases where the firm depends on IT as a strategic resource proves to be a good explanation for effective decisions leading to higher performance. Viewing IT as a strategic resource alone does not lead to positive business unit outcomes, but the moderating influence of Extent of Control is found to establish the complex statistical relationship with business unit performance. For these reasons, it is critical that a theoretically grounded firm-wide process for decisions on locating IT control is in place to capture business value.
Kathy S. SchwaigEmail:

Detmar Straub   The J. Mack Robinson Distinguished Professor of Information Systems at Georgia State University, Detmar has conducted research in the areas of IT outsourcing, computer security, Net-enhanced organizations (e-Commerce), technological innovation, international IT studies, and IS research methods. He holds a DBA (Doctor of Business Administration) in MIS from Indiana and a Ph.D. in English from Penn State. Detmar has published over 145 papers in journals such as MIS Quarterly, Management Science, Information Systems Research, Journal of MIS, Journal of AIS, Decision Sciences Journal, Organization Science, Communications of the ACM, Information & Management, Communications of the AIS, IEEE Transactions on Engineering Management, DATA BASE, OMEGA, Academy of Management Executive, and Sloan Management Review. Detmar is Editor-in-Chief of MIS Quarterly and former Senior Editor for Information Systems Research and Journal of the AIS and Co-Editor of DATA BASE for Advances in Information Systems. He is also an Associate Editor for the Journal of International Management. In the past he has served as Associate Editor for Management Science and Information Systems Research, and Associate Publisher/Senior Editor/Associate Editor for MIS Quarterly as well as editorial board member on a variety of other journals. Former VP of Publications for the Association of Information Systems (AIS), he has held roles as co-program chair for AMCIS and ICIS and was elected an AIS fellow in 2005. Peter Weill   is an MIT Senior Research Scientist and joined MIT Sloan faculty in 2000 to become director of MIT Sloan’s Center for Information Systems Research (CISR). MIT CISR is funded by sixty corporate sponsors, and undertakes practical research on how firms generate business value from IT. Peter has written award-winning books, journal articles, and case studies on how firms govern, invest in and get value from IT. Peter’s co-authored books include: Enterprise Architecture as Strategy: Creating a Foundation for Business Execution (Harvard Business School Press, July 2006), IT Governance: How Top Performers Manage IT Decision Rights for Superior Results (2004), Leveraging the New Infrastructure: How market leaders capitalize on information technology (1998) and Place to Space: Migrating to eBusiness Models, (2001) which won one of the Library Journal of America’s best business book of the year awards and was reviewed by the New York Times. Before joining Sloan as Director of CISR, Peter was Foundation Professor and Chair of Management and a member of the Board of Directors of Melbourne Business School. Peter has been an Associate Editor for MISQ and ISR and was a program co-chair for ICIS2000 in Brisbane. Kathy S. Schwaig   is an Associate Professor of Information Systems and Associate Dean for Administration in the Coles College of Business at Kennesaw State University. Her research interests include information privacy, outsourcing, project management, knowledge management and electronic commerce. She also serves as a business consultant in information systems strategy. Dr. Schwaig has published in the Communications of the ACM, The Journal of Management Information Systems, DATABASE, Information and Organization, and Information Systems Research among others.  相似文献   
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