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31.
Recent years have witnessed major governmental initiatives regarding critical infrastructure protection (CIP). During that same time, critical infrastructures (CIs) have undergone massive institutional restructuring under the headings of privatization, deregulation and liberalization. Little research has gone into understanding the interactions between these two developments. In this article, we outline the consequences of institutional restructuring for the changing ways in which CIs ensure the reliability and security of their networks and services. Neither Normal Accident Theory nor High‐Reliability Theory can account for reliability under these conditions. We then investigate the implications of these findings for CIP. 相似文献
32.
Shuman Daniel W.; Cunningham Mark D.; Connell Mary A.; Reid William H. 《Canadian Metallurgical Quarterly》2003,34(3):233
Forensic psychology has made important gains in professional recognition and stature in the courts, resulting in increasing demands for mobility of expertise. Current regulations regarding the interjurisdictional temporary forensic practice of psychology, however, are characterized by variability of regulations, ambiguity and inaccessibility, and continuing total barriers. A uniform, well-reasoned policy is needed. A conceptual basis for such a policy is provided by a discussion of licensing rationales and the application of these to forensic practice. Uniformity, public and professional protection, and practicability are identified as fundamental regulatory criteria. A Model Rule Regarding the Temporary Forensic Practice of Psychology is proposed for adoption by state licensing boards on a nationwide basis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
David M. Mahli Mark J. Steffenhagen Lin-lin Xing J. Edward Glass 《Journal of Coatings Technology》2003,75(938):39-51
Surfactants, varying in their chemical composition and hydrophobic behavior, are used in the formulation of a waterborne coating.
These differences influence their aggregation in micellar structures, their interaction with associative thickeners, and in
particular, the synergies present in their competitive adsorptions on the disperse phases in a waterborne coating. Adsorption
of HEUR thickeners on latexes and the ability of surfactants to displace them from those surfaces is an important variable
in the dispersion’s viscosity. With large particle latexes, viscosity increases arise primarily from the network built through
the interaction of HEURs with surfactants in the aqueous phase. Fluorescence is used to verify the mechanism by which surfactants
enhance associative thickener viscosities. That is best achieved with nonionic surfactants, because of their synergies with
large hydrophobe HEURs at low concentration. With decreasing latex particle size the adsorbed species is an important contributor
to the dispersion’s viscosity through its contribution to the latex’s effective volume fraction increase and when the size
of the adsorbed HEUR is matched to the separation distances of the latex at 0.25 volume fraction. Achieving controlled shear-thinning
behavior in small particle size latex paints with the economic constraints on the amount of HEUR required to obtain 90 KU
viscosities are discussed.
Presented at the 80th Annual Meeting of the Federation of Societies for Coatings Technology, October 30–November 1, 2002,
in New Orleans, LA.
Polymer and Coatings Dept., Fargo, ND 58103. 相似文献
34.
Choosing a standard speed for visual inspection is difficult using standard work measurement techniques. This paper uses a different approach, taking a model of human functioning in inspection and deriving an optimum speed of working so as to balance the cost of time against the cost of errors. Random search is used as the model and both self-paced and externally-paced conditions are derived for multiple fault types. Optimization using a Golden Section search is used to provide optimum inspection speed. 相似文献
35.
The primary visual sources of depth and size information are binocular cues and motion parallax. Here, the authors determine the efficacy of these cues to control prehension by presenting them in isolation from other visual cues. When only binocular cues were available, reaches showed normal scaling of the transport and grasp components with object distance and size. However, when only motion parallax was available, only the transpont component scaled reliably. No additional increase in scaling was found when both cues were available simultaneously. Therefore, although equivalent information is available from binocular and motion parallax information, the latter may be of relatively limited use for the control of the grasp. Binocular disparity appears selectively important for the control of the grasp. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Erp Implementation Failure: A Case Study 总被引:5,自引:0,他引:5
While it is true that successful implementation of an enterprise resource planning (ERP) system is a task of Herculean proportions, it is not impossible. If your organization is to reap the benefits of ERP, it must first develop a plan for success. But “prepare to see your organization reengineered, your staff disrupted, and your productivity drop before the payoff is realized.” Implementing ERP must be viewed and undertaken as a new business endeavor and a team mission, not just a software installation. Companies must involve all employees, and unconditionally and completely sell them on the concept of ERP for it to be a success. A successful implementation means involving, supervising, recognizing, and retaining those who have worked or will work closely with the system. Without a team attitude and total backing by everyone involved, an ERP implementation will end in less than an ideal situation. This was the situation for a soft drink bottler that tried to cut corners and did not recognize the importance of the people so heavily involved and depended on. 相似文献
37.
Myers Mark G.; MacPherson Laura; McCarthy Denis M.; Brown Sandra A. 《Canadian Metallurgical Quarterly》2003,15(2):163
The goal of the present studies was to construct and validate a short form of the 50-item Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991), a measure of smoking outcome expectancies. In Study 1, a 21-item short form (S-SCQ) was derived from a sample of 107 young adults previously treated for substance abuse. In Study 2, the measure was cross-validated on 125 adolescents in treatment for substance abuse. Confirmatory factor analyses revealed good model fit and factorial invariance for the 4 S-SCQ subscales across both samples. Validation analyses on each sample found that subscale scores generally correlated significantly with smoking-related variables. The present studies provide initial evidence for the utility of the S-SCQ when used with young adults and adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
A wireless LAN service integration architecture based on current wireless LAN hot spots is proposed so that migration to a new service becomes easier and cost effective. The proposed architecture offers wireless LAN seamless roaming in wireless LAN/cellular mobile networks. In addition, a link-layer-assisted mobile IP handoff mechanism is introduced to improve the network/domain switching quality in terms of handoff delay and packet loss. An application layer end-to-end authentication and key negotiation scheme is proposed to overcome the open-air connection problem existing in wireless LAN deployment. The scheme provides a general solution for Internet applications running on a mobile station under various authentication scenarios and keeps the communications private to other wireless LAN users and foreign network. A functional demonstration of the scheme is given. The research results can contribute to rapid deployment of wireless LANs. 相似文献
39.
An imbalance between helper T cell type 1 (Th1) and helper T cell type 2 (Th2) activation can result in immunodysregulations leading to impaired cell-mediated immunity with an increased incidence of infectious disease or cancer and/or aberrant humoral immunity that may culminate with an autoimmune disease. Mercury, a heavy-metal toxicant, is known to induce renal autoimmunity characterized by a predominant Th2 response. Lead, another metal toxicant, causes enhanced B cell activities and impairs host resistance to several bacterial and viral infections. In addition, Pb was reported to enhance Th2 proliferation and inhibit Th1 proliferation. The differential effects of Pb on Th subset activation have been further investigated. In vitro IL-4 production by a Th2 clone was significantly increased by the addition of PbCl2, whereas IFN gamma production by a Th1 clone was decreased by the addition of PbCl2. When BALB/c mice were subcutaneously exposed to PbCl2, ex vivo Il-4 production by anti-CD3-stimulated splenic T cells was enhanced, but IFN gamma production was inhibited. Additionally, the plasma IL-4 and IgE levels of Pb-exposed mice were increased, and the plasma IFN gamma levels were significantly lowered in the absence of any additional exogenous antigen. In vitro, ex vivo, and in vivo treatment with HgCl2 produced similar findings. This study is the first report of the preferential activation of a Th2 response by Pb in vivo and suggests that PB, like Hg, may induce autoimmune responses by upsetting the balance between Th1- and Th2-like cells, which could enhance production of antibodies to self antigens. 相似文献
40.
DC Sutton R Kluger SU Ahmed SC Reimold JB Mark 《Canadian Metallurgical Quarterly》1994,108(3):576-582
This study assessed the value of biplane transesophageal echocardiographic assessment of diastolic flow reversal in the descending aorta as an alternative to Doppler color flow imaging in determining severity of aortic regurgitation. In 45 patients undergoing cardiac operations, the severity of aortic regurgitation was assessed by semiquantitative grading of the width of the Doppler color flow regurgitant jet relative to the left ventricular outflow tract, and the presence of diastolic flow reversal was assessed with pulsed-wave Doppler measurements at three sites in the descending aorta. In four patients, the diastolic flow reversal method was the only available form of assessment because of inadequate visualization of the left ventricular outflow tract beneath a mitral valve prosthesis. Diastolic flow reversal in the descending aorta was not observed in patients without aortic regurgitation and was always present in patients with severe aortic regurgitation. Aortic valve replacement successfully eliminated descending aortic flow reversal in all 19 patients in whom it was present before valve replacement. Identification of diastolic flow reversal at multiple sites in the descending aorta with biplane transesophageal echocardiography helps to confirm the presence of severe aortic regurgitation and can serve as an alternative method of assessment when visualization of the left ventricular outflow tract is impaired. 相似文献