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101.
Ch R V S Nagesh T S Sitaraman C S Ramachandran R B Subramanyam 《Bulletin of Materials Science》1994,17(6):1167-1179
Titanium has emerged as a major structural metal for a wide range of industrial applications due to its attractive engineering
properties. India has a large and rich reserve base for this metal in the beach sands of the eastern and southern regions
with well established production facilities for their separation into individual minerals. Research and Development activities
for establishing the metal production technology have been underway in the country for over two decades. The Defence Metallurgical
Research Laboratory, Hyderabad, has already demonstrated the metal production technology by the conventional Kroll process
on 2000 kg/batch scale and is now all set for demonstrating the same by the more advanced, energy efficient combined process
route on 4000 kg/batch scale. The paper reviews the R & D efforts undertaken so far in the field of metal extraction with
emphasis on the current status of this developmental activity at DMRL. 相似文献
102.
103.
This paper establishes a design technique for control input histories resulting in higher confidence levels in the estimate of lateral stability and control derivatives of light aircraft, and which cause dynamic motion favorable to reductions in numerical divergence tendencies in the identification algorithms. A combined aileron and rudder input design is demonstrated for the Cessna 172 aircraft. 相似文献
104.
Narayana Prasad Padhy S.R. Paranjothi V. Ramachandran 《Microelectronics Reliability》1997,37(5):733-737
The major aim of this paper is to develop a hybrid model to determine the unit commitment schedule of generating units. It is proposed to produce the unit commitment schedules in two steps. In the first step, the input layer of the neural network is designed to adopt nonlinear fuzzy membership values of the load demand profile. In the second step, an adaptive expert system is used to manipulate the schedules by using rule-base and inference mechanism. To demonstrate the effectiveness of this model, extensive studies have been performed for different load profiles belonging to the power systems of Tamilnadu consisting of thermal, nuclear, hydro, wind and diesel power plants. 相似文献
105.
The present investigation is aimed toward the development of knowledge-based aids for the design of mechanical systems. We have developed and implemented the knowledgebased aid system, which includes MEET and DPMED. The basic approach of MEET follows along the lines ofDesign=Refinement+ Constraint Propagation. This approach has been proven successful in the circuit design domain. Our attempts to utilize MEET have convinced us that we need to extend this methodology to solve mechanical design problems. The DPMED methodology has been applied to design gear-pairs, v-belts, bearings, and shafts. Rules for selecting materials, critical design criteria, and so on are incorporated as part of the rule-system. In order for DPMED to select the design parameter values within the feasible design space, design criteria need to be investigated. Based on these criteria and input/output specifications, DPMED attempts to perform parameter selections. DPMED uses a general hill-climbing algorithm to guide the search. 相似文献
106.
Generation of the 2-variable very-strictly-Hurwitz polynomial (VSHP) using properties of derivatives of even or odd parts of Hurwitz polynomials and their applications in designing 2-D recursive digital filters satisfying prescribed magnitude and constant group delay response is described. 相似文献
107.
It has been found that stabilization of austenite by hydrogen is governed not by its amount but by the manner of its introduction into the austenite just prior to transformation into martensite. In this case stabilization is to be understood as a decreasing tendency to transformation into martensite. The experimental results obtained using an appropriate material (steel No. 1.4576) show that cathodic impregnation brings about a stabilization of austenite as defined above. 相似文献
108.
P.Subhadra Ramachandran M.N. Mathur S.K. Ojha 《International Journal of Engineering Science》1979,17(5):625-639
Van Dyke's singular perturbation technique has been used to study the heat transfer in the flow of a micropolar fluid past a curved surface with suction and injection. The conditions for similar solutions of the thermal boundary layer equations have been obtained. In addition to the usual “no slip” condition for velocity, the two types of boundary conditions used for microrotation are: (i) no relative spin on the boundary; (ii) the anti-symmetric part of the stress tensor vanishes at the boundary. The effect of suction or injection on velocity, microrotation, temperature, skin friction coefficient, wall couple stress coefficient, displacement and momentum thicknesses, rate of heat transfer and adiabatic wall temperature have been studied. It is observed that with the increase of injection velocity, the thickness of the boundary layer is increased and the local drag is reduced. A comparison with the results obtained for a Newtonian fluid reveals that the microelements present in the fluid reduce the velocity and frictional drag, and cool the boundary. 相似文献
109.
The stability, sensitivity, and static velocity error coefficient of an induction motor (IM) drive fed by a current-source inverter (CSI) are analyzed to obtain the necessary information for the design of a practical system. These analyses are considered useful for determining an appropriate subsystem to compensate for performance deficiencies 相似文献
110.