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41.
The structural changes inside the French innovation system have impacted the role of defense firms since the late 1980s. Major changes have affected the defense budget and public R&D funding system in particular. The aim of this article is to understand French defense firms’ repositioning within the National Innovation System (NIS) based on an analysis of their R&D behavior over a long period of time (1987–2010). We show that French defense firms remain major players in the NIS and faced up to these major changes by adapting the funding of their R&D and their research priorities and rolling out new innovation capabilities. Additionally, they developed new innovation models to take advantage of new collaborative partnerships developed for civil and military markets.  相似文献   
42.
This paper tackles the general single machine scheduling problem, where jobs have different release and due dates and the objective is to minimize the weighted number of late jobs. The notion of master sequence is first introduced, i.e., a sequence that contains at least an optimal sequence of jobs on time. This master sequence is used to derive an original mixed‐integer linear programming formulation. By relaxing some constraints, a Lagrangean relaxation algorithm is designed which gives both lower and upper bounds. The special case where jobs have equal weights is analyzed. Computational results are presented and, although the duality gap becomes larger with the number of jobs, it is possible to solve problems of more than 100 jobs. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 50: 2003  相似文献   
43.
The maintenance strategy considered in this article is in the class of block replacement policies. The working unit is replaced by new ones at instants T,2T,3T,… independently of the age and state of the unit. If a failure occurs between these instants, the random repair cost is evaluated. If it is smaller than a predetermined control limit then a minimal repair is carried out. Otherwise the unit is replaced by a used unit. The performance of this maintenance strategy is evaluated in terms of average total cost per time unit over an infinite time span. The mathematical model is defined and several analytical results are obtained. A computer program has been written, which solves the mathematical problem, and some examples are given for the cases where the underlying life distribution is gamma, Weibull or truncated normal.  相似文献   
44.
Why does joint defence production of advanced weapons systems, which appears like a logical choice at first, become harder for both the primary production state and its allies to manage and justify as the acquisition process runs its course? To answer this question, we analyze the multinational politics of the F-35 JSF with a focus on how secondary states who have bought into the program are affected by domestic politics within the primary production state. We find that US congressional and bureaucratic politics, cuts to US defence spending, and a desire to retain tight control over the program has locked allies into a program with which they have little leverage. Potentially losing the ability to fight along side the US if they don’t follow through, coupled with inter-Alliance pressures, leaves secondary states who are involved with the F-35 program, vulnerable to the whims of US domestic politics.  相似文献   
45.
This paper investigates what motivates young people to volunteer for peace-keeping or peace-enforcing missions and how their motives change between pre- and post-deployment. Data include information about social and military background, and motives for more than 600 soldiers, 444 of whom answered the survey both before and after deployment. Soldiers are deployed to different missions under the same circumstances. To conceptualize motives among soldiers, we use factor analysis and find three factors: challenge, self-benefit, and fidelity. Challenge represents an occupational orientation; fidelity, an institutional orientation; and self-benefit, a desire for adventure. Exploiting the within-subject design of our data, we find that pre- and post-deployment motives vary significantly according to the type of mission and soldiers’ previous experiences (first-timers or experienced soldiers). Our results suggest that after the mission, peace-keepers are generally more disappointed than peace-enforcers. Our results also show that self-benefit motives are important for younger soldiers with only a high school education, and that this group usually serves as peace-enforcers during their gap year.  相似文献   
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We investigate the problem in which an agent has to find an object that moves between two locations according to a discrete Markov process (Pollock, Operat Res 18 (1970) 883–903). At every period, the agent has three options: searching left, searching right, and waiting. We assume that waiting is costless whereas searching is costly. Moreover, when the agent searches the location that contains the object, he finds it with probability 1 (i.e. there is no overlooking). Waiting can be useful because it could induce a more favorable probability distribution over the two locations next period. We find an essentially unique (nearly) optimal strategy, and prove that it is characterized by two thresholds (as conjectured by Weber, J Appl Probab 23 (1986) 708–717). We show, moreover, that it can never be optimal to search the location with the lower probability of containing the object. The latter result is far from obvious and is in clear contrast with the example in Ross (1983) for the model without waiting. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009  相似文献   
48.
Postmodern contradictions in postcolonial Nigeria have led to the fetishisation of alternative local security measures often labelled as vigilante activities. The profiling of these groups as ethnic militia often undermines their essential bid to provide security while delimiting security needs to the physical. The fallouts of such profiling are frictions between federal security agents and ethnic-based security groups, often resulting in violence, as exemplified by the 7 May 2013 incident between the Nigerian federal security agents and the Ombatse. This study focuses on the emergence and activities of the Ombatse as an alternative security apparatus of the Eggon. It presents three years of field research which entailed the use of ethnography, key informant interviews and observation. The findings reveal that the Ombatse emerged to assert historical legitimacy for both the physical and spiritual securitisation of the Eggon through a return to the ancestral ways of social engineering. The study considers the security challenges in Nigeria, and also situates the Eggon historical context within political, religious, sociocultural and economic intersections of securitisation. It concludes that the Ombatse situates its legitimacy within the Eggon past and retains its relevance through the holistic focus of providing both physical and spiritual security.  相似文献   
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50.
In clinical circles, the concept of “moral injury” has rapidly gained traction. Yet, from a moral philosophical point of view the concept is less clear than is suggested. That is, in current conceptualizations of moral injury, trauma’s moral dimension seems to be understood in a rather mechanistic and individualized manner. This article makes a start in developing an adequately founded conceptualization of the role of morality in deployment-related distress. It does so by reviewing and synthesizing insights from different disciplines into morality and trauma. This discussion will lead to three positions: (1) values and norms are by definition characterized by conflict, (2) moral conflict may entail important social dimensions, and (3) moral conflict may lead to altered beliefs about previously held values. These insights provide important steps in further developing conceptions of the role of morality in deployment-related suffering.  相似文献   
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