Method of welding joint in closed vessel improves quality of seam

To facilitate welding of closed vessels, a metal backup strip is used at the junction inside the vessel. After welding from the outside, this strip is dissolved by a chemically reactive solvent poured through a filler hole into the vessel

Air Flow Investigation for Location of Angle of Attack Head on a JN4h Airplane

The technical staff of the NACA at Langley Field, has made a series of free flight tests with a JN4h airplane in order to find the best place for an instrument for measuring the angle of attack. A "neutral zone" was found where the air remains either at rest relative to the undisturbed air beyond the influence of the airplane, or is set in motion parallel to the motion of the airplane. This zone is about midway between the two wings and slightly in front of, or at the vertical plane through the leading edges of the wings but the exact position as well as the outlines of the zone varies considerably as the conditions of flight change

Why are people afraid of the dentist?:Observations and explanations

Objective: The aim of this review was to explore the peer-reviewed literature to answer the question: 'Why are people afraid of the dentist?' Method: Relevant literature was identified by searching the following on-line databases: PubMed, PsycInfo, the Cochrane Library and Google Scholar. Publications were extracted if they explored the causes and consequences of dental fear, dental anxiety or dental phobia. Results: The research evidence suggests that the causes of dental fear, dental anxiety or dental phobia are related to exogenous factors such as direct learning from traumatic experiences, vicarious learning through significant others and the media, and endogenous factors such as inheritance and personality traits. Each individual aetiological factor is supported by the evidence provided. Conclusions: The evidence suggests that the aetiology of dental fear, anxiety or phobia is complex and multifactorial. The findings show that there are clear practical implications indicated by the existing research in this area: a better understanding of dental fear, anxiety and phobia may prevent treatment avoidance. © 2013 S. Karger AG, Basel.</p

Forest resource information system

Remote sensing technology providing St. Regis with an independent operational system and having LANDSAT data as a significant and viable contributor was documented and transferred. Primary emphasis was placed on documenting developmental LARSYS (LARSYSDV) software modules. Timelines and a short description of the software documentation process is given

On The Origin of Super-Hot Electrons from Intense Laser Interactions with Solid Targets having Moderate Scale Length Preformed Plasmas

We use PIC modeling to identify the acceleration mechanism responsible for the observed generation of super-hot electrons in ultra-intense laser-plasma interactions with solid targets with pre-formed plasma. We identify several features of direct laser acceleration (DLA) that drive the generation of super-hot electrons. We find that, in this regime, electrons that become super-hot are primarily injected by a looping mechanism that we call loop-injected direct acceleration (LIDA)

Device measures fluid drag on test vehicles

Electromechanical drag balance device measures the aerodynamic drag force acting on a vehicle as it moves through the atmosphere and telemeters the data to a remote receiving station. This device is also used for testing the hydrodynamic drag characteristics of underwater vehicles