Productive War: A Re-Conceptualisation of War

Conventional wisdom on the phenomenon of war is criticised for providing little relevant guidance to deal with the security challenges of our era. One reason is that this attitude uncritically assumes power as synonymous with force. In response, ‘productive war’ is here proposed as a re-conceptualisation of war based on Michel Foucault's alternative understanding of power. Productive war appreciates the role of violence but subordinates it to non-kinetic dynamics influencing the dimension of meaning in international security. This theoretical perspective provides a conceptual framework to deal with the dynamics of political mobilisation essential to create public support for nation-building abroad and for visions of world order.     

FE modeling of concrete beams and columns reinforced with FRP composites

Compression and flexure members such as columns and beams are critical in a structure as its failure could lead to the collapse of the structure. In the present work, numerical analysis of square and circle short columns, and reinforced concrete (RC) beams reinforced withfiber reinforced polymer composites are carried out. This work is divided into two parts. In thefirst part, numerical study of axial behavior of square and circular concrete columns reinforced with Glass Fiber Reinforced Polymer (GFRP) and Basalt Fiber Reinforced Polymer (BFRP)bars and spiral, and Carbon Fiber Reinforced Polymer (CFRP) wraps is conducted. The results of the first part showed that the axial capacity of the circular RC columns rein-forced with GFRP increases with the increase of the longitudinal reinforcement ratio. In addition, the results of the numerical analysis showed good correlation with the experimental ones. An interaction diagram for BFRP RC columns is also developed with considering various eccentricities. The results of numerical modeling of RC columns strengthened with CFRP wraps revealed that the number and the spacing between the CFRP wraps provide different levels of ductility enhancement to the column. For the cases considered in this study, column with two middle closely spaced CFRP wraps demonstrated the best performance. In the second part of this research,flexural behavior of RC beams reinforced with BFRP, GFRP and CFRP bars is investigated along with validation of the numerical model with the experimental tests. The results resembled the experimental observations that indicate significant effect of the FRP bar diameter and type ont he flexural capacity of the RC beams. It was also shown that Increasing the number of bars while keeping the same reinforcement ratio enhanced the stiffness of the RC beam.     

On the median residual lifetime and its aging properties: A characterization theorem and applications

This paper is devoted to study several aspects of the median residual life function (MERLF). In reliability studies, it is well known that, although the MERLF have several advantages over the mean residual life function (MRLF), the MRLF has the good property of uniquely determine a life distribution whereas either the median residual life function (MERLF) or an α‐percentile residual life do not have such good property. We shall give a characterization result where knowledge of both the MERLF and the survival function on an interval does uniquely determine the distribution. Moreover, in order to apply this characterization in practical situations, we propose a method to estimate the necessary information of the survival function. Relationships between analytical properties of the survival function and its associated MERLF are also obtained. Bryson and Siddiqui [J Am Statist Assoc 64 (1969), 1472–1483] proved relationships among seven criteria for aging, out of which two contained the MRLF (decreasing MRLF and net decreasing MRLF). In this paper, we prove that the same pattern of relationships holds if the MRLF is replaced by the MERLF. We also examine the aging criteria corresponding to an increasing MERLF and show that there is no relation between the behavior (increasing or decreasing) of the MERLF and of the MRLF. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005     

Capacity allocation with machine duplication in semiconductor manufacturing

The manufacturing process for a computer chip is complex in that it involves a large number of distinct operations requiring a substantial lead‐time for completion. Our observations of such a manufacturing process at a large plant in the United States led us to identify several tactical and operational problems that were being addressed by the production planners on a recurring basis. This paper focuses on one such problem. At a tactical level, given a demand forecast of wafers to be manufactured, one specific problem deals with specifying which machine or machine groups will process different batches of wafers. We address this problem by recognizing the capacity limitations of the individual machines as well as the requirement for reducing operating and investment costs related to the machines. A mathematical model, which is a variation of the well‐known capacitated facility location problem, is proposed to solve this problem. Given the intractability of the model, we first develop problem specific lower bounding procedures based on Lagrangean relaxation. We also propose a heuristic method to obtain “good” solutions with reasonable computational effort. Computational tests, using hypothetical and industry‐based data, indicate that our heuristic approach provides optimal/near optimal solutions fairly quickly. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005