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[en] The Central Office for the Suppression of Trafficking in Arms, Explosives and Sensitive Materials (OCRTAEMS) was created on 13 December 1982. For around twenty years it was no more than a simple group within the Anti-Terrorist Division of the Central Directorate of the Criminal Police (DCPJ). At that time, it was almost exclusively terrorists who had recourse to explosives and weapons of war, hence the name. In April 2002, following the Nanterre massacre (March 2002), where a mad marksman decimated the Municipal Council of the town during a meeting, it was decided to reactivate this office. Its mandate was also redefined to cover general suppression of arms trafficking, whatever the area of crime: organized crime, common law crime, terrorism, crime in sensitive areas, etc. The arms office was removed from the National Anti-Terrorist Division (DNAT) and became a separate office directly under the Subdirectorate for Criminal Affairs. The number of its staff was set at 30. Its function is to promote and coordinate the fight against crime relating to the manufacture and possession of, trading in and illicit use of weapons, ammunition, explosives and sensitive materials (nuclear, radiological, biological and chemical). Its structure is traditional and comprises two inquiry groups, one technical and legal analysis unit and an operational documentation section. It has a ballistics and weapons expert, an explosives specialist and a nuclear, radiological, biological and chemical threat consultant. French investigation procedures and technical resources are discussed. International tensions and the current terrorist situation have prompted the security services to include all kinds of attack hypotheses in their prevention or response plans. The information services (Directorate for National Surveillance or General Information) are responsible at the Ministry of the Interior for collecting information which may be subject to judicial use by such specialized services as the National Anti-Terrorist Division (when the threat is terrorist in nature) or the Central Office for the Suppression of Trafficking in Arms, Explosives and Sensitive Materials in the case of illicit trafficking in nuclear, radiological, chemical or biological substances. In the latter area, OCRTAEMS receives information through international channels such as ICPO-Interpol and Europol, and national information relayed through territorial criminal police or gendarmerie bodies. The use made of it at central level shows that much nuclear or radiological material is not kept under optimal security conditions and that the dismantling of some military or industrial equipment is giving rise to a profitable trade managed by criminal organizations. Where the presence of sensitive materials is confirmed, the office can have recourse to the operational skills of the central interministerial task force which answers directly to the head of the RAID (Investigation, Assistance, Intervention, Dissuasion) force, and the specialized services of the CEA for nuclear or radiological threats. Thanks to the central position of the office, its representatives participate very regularly in national or international bodies to discuss security as it relates to sensitive materials. The service was also recently designated by the Minister of the Interior as the French contact point for the implementation of an early warning network at European level for weapons, explosives and sensitive materials
[en] A new control approach to achieve robust hopping against perturbations in the sagittal plane is presented in this paper. In perturbed hopping, vertical body alignment has a significant role for stability. Our approach is based on the virtual pendulum concept, recently proposed, based on experimental findings in human and animal locomotion. In this concept, the ground reaction forces are pointed to a virtual support point, named virtual pivot point (VPP), during motion. This concept is employed in designing the controller to balance the trunk during the stance phase. New strategies for leg angle and length adjustment besides the virtual pendulum posture control are proposed as a unified controller. This method is investigated by applying it on an extension of the spring loaded inverted pendulum (SLIP) model. Trunk, leg mass and damping are added to the SLIP model in order to make the model more realistic. The stability is analyzed by Poincaré map analysis. With fixed VPP position, stability, disturbance rejection and moderate robustness are achieved, but with a low convergence speed. To improve the performance and attain higher robustness, an event-based control of the VPP position is introduced, using feedback of the system states at apexes. Discrete linear quartic regulator is used to design the feedback controller. Considerable enhancements with respect to stability, convergence speed and robustness against perturbations and parameter changes are achieved. (paper)
[en] The purpose of this study was to find out useful radiological projection of shoulder subluxation in patients with post-stroke hemiplegia. A total of 33 patients with post-stroke hemiplegia were included(20 men and 13 women, mean age 62.3 years) and having the subluxed shoulder over one finger breath. The shoulder subluxation was determined as the ratio of the radiographic vertical and horizontal distance. The vertical distance was determined by measuring the distance between the most inferolateral point of the acromion and the central point of the humeral head. The horizontal distance was determined by measuring the distance between the central point of the glenoid fossa and the central point of the humeral head. To measure of the shoulder subluxation, the shoulder AP, axial and transthoracic lateral projections were taken on both affected and unaffected shoulders. We analyzed the difference of subluxation distance by t-test. When patients was in sitting position, the average time of being shoulder subluxation was 123 second. There was significant difference between supine(49.90±13.6 mm) and sitting position(60.72±16.3 mm) in the vertical distance of shoulder anterior-posterior projection. Also, there was significant difference on transthoracic lateral projections, Affected 35.92±6.2 mm, Unaffected 28.76±5.4 mm. But in case of shoulder axial projection(supine position), there was no significant difference (Unaffected and affected was 23.01±9.0 mm, 22.45±8.2 mm each). Radiological projection of shoulder subluxation has diagnostic value when it goes after check out the process of subluxation through finger breadth test. For this, patients must be in sitting and shoulder neutral position about 2 minutes. In addition, Shoulder anterior-posterior and transthoracic projection were significant to diagnose subluxation. But in axial projection, there wasn't meaningful differences.
[en] This study proposes a method for predicting the reliability of the barrel in small arms by analyzing the dispersion. The periodicity with which the barrel needs to be changed can be determined by detecting the inner surface directly or by inspecting scratches inside the barrel using an optical sensor. However, soldiers and directors in the logistics command need a more easy way to check the periodicity of barrel. Therefore, this study focuses on the relation between the firing round and the dispersion. A simple equation can be experimentally derived from pre tests and analysis. This equation is confirmed through firing tests. In this sense, it can be easily applied to determine the periodicity with which the barrel of small arms needs to be changed in the field army
[en] An instability driven by an electron temperature gradient in combination with sheath boundary conditions at a divertor plate is considered. It is shown that there exists a mode localized between the divertor plate and the x point. Further propagation of the mode is terminated by a strong shear near the x point. A ''heuristic'' boundary condition at the control surface situated somewhat below the x point is suggested. The mode manifests a strong dependence on the radial tilt of the divertor plate, thereby providing some degree of control over the plasma transport in the divertor leg. Estimates of the diffusion coefficient show that it may reach the Bohm value
[en] The ability to traverse unknown, rough terrain is an advantage that legged locomoters have over their wheeled counterparts. However, due to the complexity of multi-legged systems, research in legged robotics has not yet been able to reproduce the agility found in the animal kingdom. In an effort to reduce the complexity of the problem, researchers have developed single-legged models to gain insight into the fundamental dynamics of legged running. Inspired by studies of animal locomotion, researchers have proposed numerous control strategies to achieve stable, one-legged running over unknown, rough terrain. One such control strategy incorporates energy variations into the system during the stance phase by changing the force-free leg length as a sinusoidal function of time. In this research, a one-legged planar robot capable of implementing this and other state-of-the-art control strategies was designed and built. Both simulated and experimental results were used to determine and compare the stability of the proposed controllers as the robot was subjected to unknown drop and raised step perturbations equal to 25% of the nominal leg length. This study illustrates the relative advantages of utilizing a minimal-sensing, active energy removal control scheme to stabilize running over rough terrain.