Vaughn College of Aeronautics and Technology

About: Vaughn College of Aeronautics and Technology is a education organization based out in New York, New York, United States. It is known for research contribution in the topics: Gravitational microlensing & Planetary system. The organization has 727 authors who have published 708 publications receiving 14082 citations. The organization is also known as: College of Aeronautics.

Deterministic Thermal Fracture Life Analysis of a Visco-elastic Cylinder

Abstract: Hollow Cylindrical structures such as a nuclear reactor containments, storage tanks, and solid rocket motor are often subjected to environmental temperature variations, which adversely influence mechanical properties such as strength, relaxation modulus, and fracture toughness. Environmental temperature changes produce cyclic thermal stresses in cylindrical structures. The thermal stress fluctuations may result in growth of a nascent crack in the body. Due to the random nature of thermal stresses, mechanical properties are time and temperature dependent. As a result crack growth will also be random. Here, a visco-elastic cylinder, modeled as a two-layer consisting of a visco-elastic inner layer in a thin elastic case, will be investigated. A finite element analysis will be carried out to determine temperature and thermal stress distribution through the cylindrical wall. Green's integral will be used to determine the crack tip stress intensity factor. The Forman crack growth rate relation, that provides crack extension in cyclically loaded structures, will be used to determine the crack propagation as the crack travels through the varying stress field. Since the stress distribution through the cylindrical wall is not uniform, a step-by-step finite element analysis will be carried out to determine stress intensity and crack growth as the crack travels through the varying stress field. Because of asymmetry in the cross section due to the existence of an initial crack, a two-dimensional finite element formulation is used for thermal analysis. The 2D analysis will take into account the stress distribution at the growing crack tip.

The U.S. Army: A Learning Organization

Abstract: Peter M. Senge, a senior lecturer at Massachusetts Institute of Technology (MIT), first introduced his learning organization concept in the early 1990’s with the publishing of The Fifth Discipline book, which has since been revised during 2006. A ‘learning organization’ focused on the development of every member with superior performance in service of that organization’s purpose. The more the organization’s members increase their ability to learn collaboratively, the more they can accomplish the higher performance, which can then effectively and positively change their organization. Learning organizations can include corporation, schools, hospitals, non-for-profits, and government agencies – basically, any organization where people are placed together to accomplish a common goal, which they could not have created on their own. Organizational learning has five lifelong disciplines: systems thinking, personal mastery, mental models, shared vision, and team learning. This paper will introduce some of the several aspects of the learning organization in the U.S. Army based on the current fight against the war on terror.

Inertial compensation study of temperature sensor in aeroengine

Abstract: Aiming at problem of measurement hysteresis of temperature sensor in a type of aeroengine,a method for inertial compensation of sensor is proposed. This method firstly gets time constant,and advice it adopt least error rule; then applys time constant to compensate; finally,secondary exponential smoothing method is used to revise the compensation curve. By simlation and experimental verification,time constant is obtained and temperature compensation is realized,and it shows that the method is effective and it can be used for inertial compensation of temperature sensor.

A Compromise Sorting Method for Electronic Warfare Target Threat Assessment

Abstract: Threat assessment for the electronic warfare(EW) targets is very important for EW combat decision making.In order to deal with the imprecision and uncertainty of factors relative to EW targets during threat assessment, a multi-attribute and group decision-making threat assessment model was set up, which focused on the selection and determination of threat assessment indexes.Based on the scale quantitative function, the qualitative indexes were quantified.Then the compromise ranking method, VIKOR, was used to sort the threat targets, thus to made the overall utility maximum and individual regret minimum.Finally, the effectiveness of threat assessment model and the feasibility of the algorithm were proved through the threat assessment simulated on the supposed view of an EW.