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431.
For many years after its introduction in the early 1990s, the cyberwar concept - which outlined a new mode of conflict that would emphasize disruption of information systems and flows - was given little credence. Over the past several years, however, cyberwars of both irregular and somewhat more conventional types have erupted (e.g., see respectively Estonia in 2007 and Georgia in 2008). Global awareness of cyberwar has risen sharply, and many nation-states are preparing their defenses, as well as their capabilities for mounting offensive operations. The American military's declaration in 2011 that cyberspace is a 'warfighting domain' highlights a need to explore the ethical implications and nuances of cyberwar. This article finds that classic jus ad bellum constructs come under great pressure from cyberwar, while jus in bello concerns may prove more manageable. Another key theme is that disproportionate attention is given to the notion of employing cyberwar 'strategically' (i.e., to strike directly at other nations' infrastructures), where its use is less likely to achieve 'victory' and is more problematic ethically. Instead, a focus on the application of cyberwar techniques in battle may lead to shorter, less bloody, 'more ethical' conflicts.  相似文献   
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Diagnostic clinics are among healthcare facilities that suffer from long waiting times which can worsen medical outcomes and increase patient no-shows. Reducing waiting times without significant capital investments is a challenging task. We tackle this challenge by proposing a new appointment scheduling policy that does not require significant investments for diagnostic clinics. The clinic in our study serves outpatients, inpatients, and emergency patients. Emergency patients must be seen on arrival, and inpatients must be given next day appointments. Outpatients, however, can be given later appointments. The proposed policy takes advantage of this by allowing the postponement of the acceptance of appointment requests from outpatients. The appointment scheduling process is modeled as a two-stage stochastic programming problem where a portion of the clinic capacity is allocated to inpatients and emergency patients in the first stage. In the second stage, outpatients are scheduled based on their priority classes. After a detailed analysis of the solutions obtained from the two-stage stochastic model, we develop a simple, non-anticipative policy for patient scheduling. We evaluate the performance of this proposed, easy-to-implement policy in a simulation study which shows significant improvements in outpatient indirect waiting times.  相似文献   
434.
The use of conventional armed forces in a deterrent role merits close consideration. Instability in weak or failing states can have global ramifications, while efforts to build stability take time. In principle, conventional deterrence can be used to buy the time required for such stabilization efforts. Attempts at deterrence will, however, need to overcome credibility problems stemming from the technical limitations associated with conventional armed forces, and with the likely requirement for multiple external actors to deter multiple intrastate audiences. While deterrence might work under certain circumstances, it will not play as central a role in strategy as it did during the Cold War.  相似文献   
435.
We formulate exact expressions for the expected values of selected estimators of the variance parameter (that is, the sum of covariances at all lags) of a steady‐state simulation output process. Given in terms of the autocovariance function of the process, these expressions are derived for variance estimators based on the simulation analysis methods of nonoverlapping batch means, overlapping batch means, and standardized time series. Comparing estimator performance in a first‐order autoregressive process and the M/M/1 queue‐waiting‐time process, we find that certain standardized time series estimators outperform their competitors as the sample size becomes large. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
436.
Certain zero-sum games are examined in which an individual player is opposed by a two-man team. The members of the team have identical interests, but must act separately during play. Most of the paper is devoted to instances in which one teammate has an opportunity to communicate to the other about their mutual opponent's strategy; but he may only be able to transmit a limited amount of information and his choice of a “message” may affect the payoff. The team must thus make economically efficient use of a limited communication opportunity. The present paper treats a variety of models, all of which are formulated as rectangular (matrix) games. Related models, some of which cannot be so formulated either because of restrictions on the team's opportunities to use mixed strategies or because they are non-zero-sum games, will be treated in another paper.  相似文献   
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