A Nuclear-Armed Iran: Possible Security and Diplomatic Implications

Analyzes how Iran's neighbors might react to a nuclear Iran: self-help in enhancing their own defenses; bandwagoning by accommodating Iran's preferences; and balancing by moving closer to the United States or forming a collective security arrangement

Optimum design of structures subject to general periodic loads

A simplified version of Icerman's problem regarding the design of structures subject to a single harmonic load is discussed. The nature of the restrictive conditions that must be placed on the design space in order to ensure an analytic optimum are discussed in detail. Icerman's problem is then extended to include multiple forcing functions with different driving frequencies. And the conditions that now must be placed upon the design space to ensure an analytic optimum are again discussed. An important finding is that all solutions to the optimality condition (analytic stationary design) are local optima, but the global optimum may well be non-analytic. The more general problem of distributing the fixed mass of a linear elastic structure subject to general periodic loads in order to minimize some measure of the steady state deflection is also considered. This response is explicitly expressed in terms of Green's functional and the abstract operators defining the structure. The optimality criterion is derived by differentiating the response with respect to the design parameters. The theory is applicable to finite element as well as distributed parameter models

North Korea and the Non-proliferation Regime

In this review of the implications of North Korea’s behaviour during 2009 on the Non-proliferation Regime, it is stressed that if North Korea cannot be deterred from its nuclear ambitions this will deliver a serious blow to the international non-proliferation regime. It will also damage the likelihood of a successful outcome at next year’s NPT Review Conference. The behaviour of North Korea so far, and especially during 2009, can be summarised as follows: failed satellite test in April, nuclear test in May, missile tests in July and additional tests of short-range missiles in October. This seems to imply that North Korea has now made its strategic choice between conciliation and hostility and that Pyongyang believes that its future security could be better preserved by maintaining a robust nuclear weapons programme. The implications of a nuclear North Korea range from diverse strategic concerns to serious humanitarian issues, while the US is faced with a number of different options, including engagement, deterrence, military pre-emption and regime change. However, all of these options have serious limitations and none promises to achieve the goal of a non-nuclear North Korea anytime soon

Corea del Norte y el nuevo paradigma de seguridad

Los últimos ensayos nucleares de Corea del Norte han provocado una nueva crisis en la península de Corea. La última detonación nuclear de Corea del Norte, sus ensayos con misiles balísticos y su provocadora retórica han causado una nueva crisis en la península de Corea. En vez de intentar obligar a este país a volver a la mesa de negociaciones a seis bandas para continuar con unas conversaciones que no llevan a ninguna parte, sería mucho mejor reconocer que el entorno de seguridad del noreste asiático ha cambiado radicalmente. Se precisa un nuevo paradigma de seguridad que haga hincapié en la disuasión y la contención y la importancia de las alianzas de EEUU

On the Birth of Isolas

Isolas are isolated, closed curves of solution branches of nonlinear problems. They have been observed to occur in the buckling of elastic shells, the equilibrium states of chemical reactors and other problems. In this paper we present a theory to describe analytically the structure of a class of isolas. Specifically, we consider isolas that shrink to a point as a parameter τ of the problem, approaches a critical value τ_0. The point is referred to as an isola center. Equations that characterize the isola centers are given. Then solutions are constructed in a neighborhood of the isola centers by perturbation expansions in a small parameter ε that is proportional to (τ-τo), with a appropriately determined. The theory is applied to a chemical reactor problem

Electronic controller for reciprocating rotary crystallizer

An electronic controller for a reciprocating rotary crystallizer is described. The heart of this system is the electronic timer circuit. A schematic along with a detailed description of its operation is given

Characteristics of Low-Latitude Coronal Holes near the Maximum of Solar cycle 24

We investigate the statistics of 288 low-latitude coronal holes extracted from SDO/AIA-193 filtergrams over the time range 2011/01/01 to 2013/12/31. We analyse the distribution of characteristic coronal hole properties, such as the areas, mean AIA-193 intensities, and mean magnetic field densities, the local distribution of the SDO/AIA-193 intensity and the magnetic field within the coronal holes, and the distribution of magnetic flux tubes in coronal holes. We find that the mean magnetic field density of all coronal holes under study is 3.0 +- 1.6 G, and the percentage of unbalanced magnetic flux is 49 +- 16 %. The mean magnetic field density, the mean unsigned magnetic field density, and the percentage of unbalanced magnetic flux of coronal holes depend strongly pairwise on each other, with correlation coefficients cc > 0.92. Furthermore, we find that the unbalanced magnetic flux of the coronal holes is predominantly concentrated in magnetic flux tubes: 38 % (81 %) of the unbalanced magnetic flux of coronal holes arises from only 1 % (10 %) of the coronal hole area, clustered in magnetic flux tubes with field strengths > 50 G (10 G). The average magnetic field density and the unbalanced magnetic flux derived from the magnetic flux tubes correlate with the mean magnetic field density and the unbalanced magnetic flux of the overall coronal hole (cc > 0.93). These findings give evidence that the overall magnetic characteristics of coronal holes are governed by the characteristics of the magnetic flux tubes.Comment: 15 figure