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1.
ABSTRACT

The paper compares political territoriality of selected jihadist violent non-state actors. Looking at selected groups that attempted to control territory (Afghan Taliban, Al-Shabaab, the Islamic State), it attempts to establish a generalization regarding the use of territory by this type of violent non-state actors. To this end, it analyses connection of territory to groups´ security provision, economic activity, and identity. Despite many differences among the groups, it concludes that these groups often utilize both territorial and personal characteristics. Territoriality of these actors is reactive as they are unable to present a sustained control in contested regions.  相似文献   

2.
Let be a basic solution to the linear programming problem subject to: where R is the index set associated with the nonbasic variables. If all of the variables are constrained to be nonnegative integers and xu is not an integer in the basic solution, the linear constraint is implied. We prove that including these “cuts” in a specified way yields a finite dual simplex algorithm for the pure integer programming problem. The relation of these modified Dantzig cuts to Gomory cuts is discussed.  相似文献   

3.
ABSTRACT

Extended deterrence has been a main pillar of the security alliance between the United States and South Korea (Republic of Korea [ROK]) since the end of the Korean War. The changing dynamics of US extended deterrence in Korea, however, affected Seoul’s strategic choices within its bilateral alliance relationship with Washington. Examining the evolution of US extended deterrence in the Korean Peninsula until the Nixon administration, this article explains why South Korea began its nuclear weapons programme in a historical context of the US–ROK alliance relationship. This article argues that President Park Chung-hee’s increasing uncertainty about the US security commitment to South Korea in the 1960s led to his decision to develop nuclear weapons in the early 1970s despite the fact that US tactical nuclear weapons were still stationed in South Korea.  相似文献   

4.
Book reviews     
Die Faszination des Verrats: Eine Studie zur Dekadenz im Ost‐West Konflikt. By Thomas Noetzel. Hamburg, Junius (1989) DM48.

Les Nations Armées. By Maurice Faivre (Preface by Pierre Messmer), Paris FEDN/Economica (1988).

Insurgency and Terrorism: Inside Modern Revolutionary Warfare. By Bard E. O'Neill, Brassey's (US), Washington, DC (1990), $19.00.

LIC 2010: Special Operations and Unconventional Warfare in the Next Century. By Rod Paschall, Brassey's (US), Washington, DC, $24.00.

Air Power and Colonial Conflict: The Royal Air Force 1919–1939. By D. E. Omissi, Manchester University Press, Manchester and New York (1990), ISBN 0–7190–2960–0. £35.00.

Key to the Sinai: The Battles for Abu Ageila in the 1956 and 1967 Arab‐Israeli Wars. By George W. Gawrych. Combat Studies Institute Research Survey No. 7, US Army Command and General Staff College, Fort Leavenworth, Kansas, 1990. $8.00.

Arms Export Regulations. Edited by Ian Anthony. SIPRI/Oxford University Press, Oxford (1991), ISBN 0–19–829158–2, £25.00.  相似文献   


5.
We consider a single-machine problem of scheduling n independent jobs to minimize makespan, in which the processing time of job Jj grows by wj with each time unit its start is delayed beyond a given common critical date d. This processing time is pj if Jj starts by d. We show that this problem is NP-hard, give a pseudopolynomial algorithm that runs in time and O(nd) space, and develop a branch-and-bound algorithm that solves instances with up to 100 jobs in a reasonable amount of time. We also introduce the case of bounded deterioration, where the processing time of a job grows no further if the job starts after a common maximum deterioration date D > d. For this case, we give two pseudopolynomial time algorithms: one runs in O(n2d(D − d) time and O(nd(D − d)) space, the other runs in pj)2) time and pj) space. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 511–523, 1998  相似文献   

6.
《防务技术》2014,10(4):384-392
Computations by density functional theory (DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation (HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that –N3 and –NN– groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMO–LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlet–Jacobs approach based on the calculated density and HOF. The results indicate that –NO2, –NF2, –NH–, –NH–NH– and –NN– groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the –CH2–, –CH2–CH2– and –CHCH– groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.  相似文献   

7.
For each n, X1(n),…Xn(n) are independent and identically distributed random variables, with common probability density function Where c, θ, α, and r(y) are all unknown. It is shown that we can make asymptotic inferences about c, θ, and α, when r(y) satisfies mild conditions.  相似文献   

8.
The author, in an expository paper [4], has presented an algorithm for choosing a non-negative vector

  相似文献   


9.
ABSTRACT

In May 2018, the Basque insurgent group Euskadi Ta Askatasuna (ETA) officially disbanded after a 60-year struggle. This inquiry assesses ETA’s violent campaigns using recent conceptual and theoretical advancements from the field of terrorism studies. Three conclusions concerning the group’s strategies of terrorism are advanced. First, ETA regularly targeted civilians to achieve goals other than coercing the Government of Spain; these objectives included outbidding rival separatist groups and spoiling negotiation processes. Second, ETA’s most rapid period of organizational growth occurred as the result of an aggressive terrorist campaign, demonstrating that civilian targeting can serve as a stimulus to rebel group recruitment. Finally, while terrorism did not advance ETA’s primary political objective of creating an independent Basque state, it did enable the group to assume a leading position within the radical Basque separatist movement, helping extend ETA’s lifespan and making the group an embedded actor within the contentious political processes surrounding the question of Basque self-determination. Collectively, these conclusions support recent theoretical findings arguing that non-state terrorism often enables insurgent groups to prolong their lifespans while paradoxically making it more difficult for them to advance their long-term political objectives.  相似文献   

10.
This paper proposes a skewness correction (SC) method for constructing the and R control charts for skewed process distributions. Their asymmetric control limits (about the central line) are based on the degree of skewness estimated from the subgroups, and no parameter assumptions are made on the form of process distribution. These charts are simply adjustments of the conventional Shewhart control charts. Moreover, the chart is almost the same as the Shewhart chart if the process distribution is known to be symmetrical. The new charts are compared with the Shewhart charts and weighted variance (WV) control charts. When the process distribution is in some neighborhood of Weibull, lognormal, Burr or binomial family, simulation shows that the SC control charts have Type I risk (i.e., probability of a false alarm) closer to 0.27% of the normal case. Even in the case where the process distribution is exponential with known mean, not only the control limits and Type I risk, but also the Type II risk of the SC charts are closer to those of the exact and R charts than those of the WV and Shewhart charts. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 555–573, 2003  相似文献   

11.
ABSTRACT

In No Use: Nuclear Weapons and U.S. National Security Policy, Thomas M. Nichols calls for a constructive rethinking about the history of nuclear weapons and the attitudes that have grown up around them. Despite dramatic reductions since the end of the Cold War, the United States still maintains a robust nuclear triad that far exceeds the needs of realistic deterrence in the twenty-first century. Nichols advocates a new strategy of minimum deterrence that includes deep unilateral reductions to the US nuclear arsenal, a no-first-use pledge, withdrawing US tactical nuclear weapons from Europe, and ending extended nuclear deterrence for allies. The weakest part of his argument eschews nuclear retaliation against small nuclear states that attack the United States, opting instead to use only conventional weapons to guarantee regime change. He admits this will entail enormous cost and sacrifice, but cites the “immorality” of retaliating against a smaller power with few targets worthy of nuclear weaponry, which totally ignores the massive underground facilities constructed to shield military facilities in many of these states. Despite this, Nichols's thoughtful approach to post-Cold War deterrence deserves thoughtful consideration.  相似文献   

12.
Suppose x1, x2, … are independently distributed random variables with Pr (xi = 1) = Pr(xi = ?1) = 1/2, and let sn =

  相似文献   


13.
We consider the problem of maximizing the number of on‐time jobs on two uniform parallel machines. We show that a straightforward extension of an algorithm developed for the simpler two identical parallel machines problem yields a heuristic with a worst‐case ratio bound of at least . We then show that the infusion of a “look ahead” feature into the aforementioned algorithm results in a heuristic with the tight worst‐case ratio bound of , which, to our knowledge, is the tightest worst‐case ratio bound available for the problem. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   

14.
Different properties of the HNBUE (HNWUE) class of life distributions (i.e.), for which \documentclass{article}\pagestyle{empty}\begin{document}$\int_t^\infty {\,\,\,\mathop F\limits^-(x)\,dx\, \le \,(\ge)\,\mu }\]$\end{document} exp(?t/μ) for t ≥ 0, where μ = \documentclass{article}\pagestyle{empty}\begin{document}$\int_t^\infty {\,\,\,\mathop F\limits^-(x)\,dx}$\end{document} are presented. For instance we characterize the HNBUE (HNWUE) property by using the Laplace transform and present some bounds on the survival function of a HNBUE (HNWUE) life distribution. We also examine whether the HNBUE (HNWUE) property is preserved under the reliability operations (i) formation of coherent structure, (ii) convolution and (iii) mixture. The class of distributions with the discrete HNBUE (discrete HNWUE) property (i.e.), for which \documentclass{article}\pagestyle{empty}\begin{document}$\sum\limits_{j=k}^\infty {\mathop{\mathop P\limits^-_{j\,\,\,}\, \le(\ge)\,\mu(1 - 1/\mu)^{^k }}\limits^{}} $\end{document} for k = 0, 1, 2, ?, where μ =\documentclass{article}\pagestyle{empty}\begin{document}$\sum\limits_{j=0}^\infty {\mathop {\mathop P\limits^- _{j\,\,\,\,\,}and\mathop P\limits^ - _{j\,\,\,\,\,}=}\limits^{}}\,\,\sum\limits_{k=j+1}^\infty {P_k)}$\end{document} is also studied.  相似文献   

15.
We re‐examine the Miguel et al. (2004 Miguel, E., Satyanath, S. and Sergenti, E. 2004. Economic shocks and civil conflict: an instrumental variables approach. Journal of Political Economy, 112(4): 725753. [Crossref], [Web of Science ®] [Google Scholar]) study of the impact of growth on civil war, using growth in rainfall as an instrument. Miguel et al. (2004 Miguel, E., Satyanath, S. and Sergenti, E. 2004. Economic shocks and civil conflict: an instrumental variables approach. Journal of Political Economy, 112(4): 725753. [Crossref], [Web of Science ®] [Google Scholar]) – in our view, erroneously – include countries participating in civil wars in other states. Restricting the conflict data to states with conflict on their own territory reduces the estimated impact of economic growth on civil war. We show how spatial correlations in rainfall growth and participation in civil conflicts induce a stronger apparent relationship in the mis‐classified data.  相似文献   

16.
We consider the problem of scheduling a set of n jobs on a single batch machine, where several jobs can be processed simultaneously. Each job j has a processing time pj and a size sj. All jobs are available for processing at time 0. The batch machine has a capacity D. Several jobs can be batched together and processed simultaneously, provided that the total size of the jobs in the batch does not exceed D. The processing time of a batch is the largest processing time among all jobs in the batch. There is a single vehicle available for delivery of the finished products to the customer, and the vehicle has capacity K. We assume that K = rD, where and r is an integer. The travel time of the vehicle is T; that is, T is the time from the manufacturer to the customer. Our goal is to find a schedule of the jobs and a delivery plan so that the service span is minimized, where the service span is the time that the last job is delivered to the customer. We show that if the jobs have identical sizes, then we can find a schedule and delivery plan in time such that the service span is minimum. If the jobs have identical processing times, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most 11/9 times the optimal service span. When the jobs have arbitrary processing times and arbitrary sizes, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most twice the optimal service span. We also derive upper bounds of the absolute worst‐case ratios in both cases. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 470–482, 2015  相似文献   

17.
Previous empirical studies on the defense spending-economic growth nexus such as Kollias et al. (2007 Kollias, C., N. Mylonidis, and S. Paleologou. 2007. “A panel data analysis of the nexus between defense spending and growth in the European Union.” Defense and Peace Economics 18 (1): 7585.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]), Mylonidis (2008 Mylonidis, N. 2008. “Revisiting the nexus between military spending and growth in the European Union.” Defense and Peace Economics 19 (4): 265272.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]), Dunne and Nikolaidou (2012 Dunne, J. P., and E. Nikolaidou. 2012. “Defense spending and economic growth in the EU15.” Defense and Peace Economics 23 (6): 537548.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) analyzed this relationship in the case of the EU15. This study extends the analysis with the inclusion of more EU members and investigates the long run causal ordering between the two variables. Findings reported herein are not uniformed across all EU members. It is also found that end of Cold War has significant negative impact on defense expenditures of former east-European countries.  相似文献   

18.
The grand aim of all science is to cover the greatest number of empirical facts by logical deduction from the smallest number of hypotheses or axioms.

Albert Einstein
Current problem: Border Emergency

Solutions in response

US Congress's response: Set immigration policies, a series of immigration reform bills and proposals.

Government's response: Make an appropriation/budget for border issues: increase law enforcement personnel and needed resources, pay officers overtime, and build fences along the border.

Scientists' response: Describe this complex problem mathematically and provide scientific solutions.  相似文献   

19.
Fourth Generation Warfare is a theory of contemporary warfare that posits a number of different ideas that are able to shed light on current conflicts. Whilst much of the debate has been concentrated on the linear development of warfare and also on analysis of the current situation of US forces in Iraq, it has resonance for a number of different conflicts taking place in Africa, if only because the US has become involved in contemporary conflicts in Somalia and the Mahgreb. There are clearly significant issues with the US-centric, flawed linear approach to history, but the actual analysis of modes of warfare has much to offer policymakers in a continent that is under-represented in the literature, and is also in danger of being forgotten in the shadow of analysis of Iraq. This paper moves on from criticising the stepped approach to history and looks at patterns of warfare in contemporary Africa, arguing that there is much in the theory that could be used to explain seemingly illogical tactics or patterns, and thus has much to tell policymakers engaged in conflict analysis.

Rebellions can be made 2 per cent active in a striking force, and 98 per cent passively sympathetic.1 ?1. T.E. Lawrence, ‘Science of Guerrilla Warfare’, 1929, published in Malcolm Brown (ed) T.E. Lawrence in War and Peace: An Anthology of the Military Writings of Lawrence of Arabia (London: Greenhill Books, 2005) p.284.   相似文献   

20.
It is the purpose of this article to illustrate how the British government reached its decision to upgrade the Polaris strategic nuclear deterrent in 1973. Using British and American documentation it is demonstrated that the strategic imperatives for upgrading Polaris were fundamental to the project. Existing accounts of the Polaris Improvement Project, however, have not given the appropriate attention to the wider US–UK political differences in this period. By doing so it is shown how in addition to the wider economic, strategic and political factors, this was of paramount significance in the Heath government opting for the ‘Super Antelope’ method in upgrading Polaris.1 1‘Super Antelope’ was the codename for the upgrade of Polaris. This was eventually changed to ‘Chevaline’. Peter Hennessy, Cabinets and the Bomb (Oxford: OUP 2007), 28–9. View all notes  相似文献   

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