Sectoral Employment Efkcts of Trade and ProductiviQ in a Small Open Economy

This paper assesses the impact of trade and technology on Belgian industrial employment. A framework is developed which incorporates employment effects of (i) export expansion (ii) impost competition and (iii) labour saving productivity improvements. In this context, evidence is found for the hypothesis that international trade induces adjustments in technology.

The Supersymmetric Fine-Tuning Problem and TeV-Scale Exotic Scalars

A general framework is presented for supersymmetric theories that do not suffer from fine-tuning in electroweak symmetry breaking. Supersymmetry is dynamically broken at a scale \Lambda \approx (10 - 100) TeV, which is transmitted to the supersymmetric standard model sector through standard model gauge interactions. The dynamical supersymmetry breaking sector possesses an approximate global SU(5) symmetry, whose SU(3) x SU(2) x U(1) subgroup is explicitly gauged and identified as the standard model gauge group. This SU(5) symmetry is dynamically broken at the scale \Lambda, leading to pseudo-Goldstone boson states, which we call xyons. We perform a detailed estimate for the xyon mass and find that it is naturally in the multi-TeV region. We study general properties of xyons, including their lifetime, and study their collider signatures. A generic signature is highly ionizing tracks caused by stable charged bound states of xyons, which may be observed at the LHC. We also consider cosmology in our scenario and find that a consistent picture can be obtained. Our framework is general and does not depend on the detailed structure of the Higgs sector, nor on the mechanism of gaugino mass generation.Comment: 53 pages, 7 figure

Plume flowfield analysis of the shuttle primary Reaction Control System (RCS) rocket engine

A solution was generated for the physical properties of the Shuttle RCS 4000 N (900 lb) rocket engine exhaust plume flowfield. The modeled exhaust gas consists of the five most abundant molecular species, H2, N2, H2O, CO, and CO2. The solution is for a bare RCS engine firing into a vacuum; the only additional hardware surface in the flowfield is a cylinder (=engine mount) which coincides with the nozzle lip outer corner at X = 0, extends to the flowfield outer boundary at X = -137 m and is coaxial with the negative symmetry axis. Continuum gas dynamic methods and the Direct Simulation Monte Carlo (DSMC) method were combined in an iterative procedure to produce a selfconsistent solution. Continuum methods were used in the RCS nozzle and in the plume as far as the P = 0.03 breakdown contour; the DSMC method was used downstream of this continuum flow boundary. The DSMC flowfield extends beyond 100 m from the nozzle exit and thus the solution includes the farfield flow properties, but substantial information is developed on lip flow dynamics and thus results are also presented for the flow properties in the vicinity of the nozzle lip

Development of a gas sampling system

Theoretical analysis and computed performance evaluation of high speed entry vehicle gas sampling syste

Extension of gage calibration study in extreme high vacuum /orbitron and magnetron studies/

Orbitron and magnetron studies for gauge calibration in extreme high vacuu

Some Secondary Effects in a Simple Piping Structure Under Heating

Bending and torsion are the principal sources of relief from thermal expansion in most piping configurations. However, secondary influences, viz., (a) axial deformation, (b) shearing deformation, (c) beam-column action, and (d) shortening owing to the difference between arc and chord, may become significant in configurations one dimension of which greatly exceeds the other two. In the following, an analysis, including these secondary influences, is made of the most fundamental configuration, an ell shape

DM approximations for the gravest frequency of a vibrating system

Estimates are made of the smallest nonzero frequency of vibration of undamped linear mechanical systems having lumped and/or distributed mass and permitting rigid body motions. The approximations are smaller than the correct values but remarkable accuracy may be achieved. The procedures are based upon methods of S. Dun*, kerley and S. G. Mikhlin.Chief of Naval Researchhttp://archive.org/details/dmapproximations00brocN

Scholarly Note: American Medical Development in Colonial Puerto Rico

Consistent with its civilizing mission, the United States sought to enhance healthcare development in its new Puerto Rican colony, one of the spoils of the Spanish-American War. American military physicians rapidly cured the population of their devastating hookworm affliction and the Rockefeller Foundation soon began exporting this imperialist triumph to the far corners of the world. Leveraging that success, the Porto Rico Anemia Commission evolved into the Institute of Tropical Medicine, predecessor to the University of Puerto Rico's School of Tropical Medicine. Issues of agricultural development would also impact insular healthcare, uniquely driving aspects of medical development. Efforts to export American successes to broader Latin America provide useful perspectives as the United States seeks to influence other underdeveloped global areas in the twenty-first century