In Defence of Mercenarism

The recent wars in Iraq and Afghanistan have been characterized by the deployment of large private military forces, under contract with the US administration. The use of so-called private military corporations (PMCs) and, more generally, of mercenaries, has long attracted criticisms. This article argues that under certain conditions (drawn from the Just War tradition), there is nothing inherently objectionable about mercenarism. It begins by exposing a weakness in the most obvious justification for mercenarism, to wit, the justification from freedom of occupational choice. It then deploys a less obvious, but stronger, argument – one that appeals to the importance of enabling just defensive killings. Finally, it rebuts five moral objections to mercenarism.</jats:p

Electrocarboxylation of chloroacetonitrile mediated by electrogenerated cobalt(I) phenanthroline

The electrocarboxylation of chloroacetonitrilemediated by [Co(II)(phen)3]2+ has been investigated. Cyclic voltammetry studies of [Co(II)(phen)3]2+ have shown that [Co(I)(phen)3]+, an 18 electron complex, activates chloroacetonitrile by an oxidative addition through the loss of a phenanthroline ligand to give [RCo(III)(phen)2Cl]+. The unstable one-electron-reduced complex underwent Co–C bond cleavage. In carbon dioxide saturated solution, CO2 insertion proceeds after reduction of the alkylcobalt complex. A catalytic current is observed which corresponds to the electrocarboxylation of chloroacetonitrile into cyanoacetic acid. Electrolyses confirmed the process and gave faradic yield of 62% in cyanoacetic acid at potentials that are about 0.3 V less cathodic than the one required for Ni(salen)

Vibrational excitation of diatomic molecular ions in strong-field ionization of diatomic molecules

A model based on the strong-field and Born-Oppenheimer approximations qualitatively describes the distribution over vibrational states formed in a diatomic molecular ion following ionization of the neutral molecule by intense laser pulses. Good agreement is found with a recent experiment [X. Urbain et al., Phys. Rev. Lett. 92, 163004 (2004)]. In particular, the observed deviation from a Franck-Condon-like distribution is reproduced. Additionally, we demonstrate control of the vibrational distribution by a variation of the peak intensity or a change of frequency of the laser pulse.Comment: 4 pages, 4 figure

A metaobject architecture for fault-tolerant distributed systems : the FRIENDS approach

The FRIENDS system developed at LAAS-CNRS is a metalevel architecture providing libraries of metaobjects for fault tolerance, secure communication, and group-based distributed applications. The use of metaobjects provides a nice separation of concerns between mechanisms and applications. Metaobjects can be used transparently by applications and can be composed according to the needs of a given application, a given architecture, and its underlying properties. In FRIENDS, metaobjects are used recursively to add new properties to applications. They are designed using an object oriented design method and implemented on top of basic system services. This paper describes the FRIENDS software-based architecture, the object-oriented development of metaobjects, the experiments that we have done, and summarizes the advantages and drawbacks of a metaobject approach for building fault-tolerant system

Fragmentation of confidential objects for data processing security in distributed systems

This paper discusses how object orientation in application design enables confidentiality aspects to be handled more easily than in conventional approaches. The idea, based on object fragmentation at design time, is to reduce processing in confidential objects; the more non confidential objects can be produced at design-time, the more application objects can be processed on untrusted shared computers. Still confidential objects must be processed on non shared trusted workstations. Rules and limits of object fragmentation are discussed together with some criteria evaluating trade-offs between fragmentation and performance

Taylor bubble moving in a flowing liquid in vertical channel: transition from symmetric to asymmetric shape

The velocity and shape of Taylor bubbles moving in a vertical channel in a Poiseuille liquid flow were studied for the inertial regime, characterized by large Reynolds numbers. Numerical experiments were carried out for positive (upward) and negative (downward) liquid mean velocity. Previous investigations in tube have reported that for upward flow the bubble is symmetric and its velocity follows the law of Nicklin whereas for certain downward flow conditions the symmetry is broken and the bubble rises appreciably faster. To study the bubble motion and to identify the existence of a transition, a 2D numerical code that solves the Navier-Stokes equations (through a VoF implementation) was used to obtain the bubble shape and the rise velocity for different liquid mean velocity. A reference frame located at the bubble tip as well as an irregular grid were implemented to allow for long simulation times without an excessively large numerical domain. It was observed that whenever the mean liquid velocity exceeded some critical value, bubbles adopted a symmetric final shape even though their initial shape was asymmetric. Conversely, if the mean liquid velocity was smaller than that critical value, a transition to a non-symmetric shape occurred, along with a correspondingly faster velocity. It was also found that surface tension has a stabilizing effect on the transition

FRIENDS - A flexible architecture for implementing fault tolerant and secure distributed applications

FRIENDS is a software-based architecture for implementing fault-tolerant and, to some extent, secure applications. This architecture is composed of sub-systems and libraries of metaobjects. Transparency and separation of concerns is provided not only to the application programmer but also to the programmers implementing metaobjects for fault tolerance, secure communication and distribution. Common services required for implementing metaobjects are provided by the sub-systems. Metaobjects are implemented using object-oriented techniques and can be reused and customised according to the application needs, the operational environment and its related fault assumptions. Flexibility is increased by a recursive use of metaobjects. Examples and experiments are also described