Measurement of mechanical and thermophysical properties of dimensionally stable materials for space applications

Mechanical, thermal, and physical property test data was generated for as-fabricated advanced composite materials at room temperature (RT), -150 and 250 F. The results are documented of mechanical and thermophysical property tests of IM7/PEEK and discontinuous SiC/Al (particulate (p) and whisker (w) reinforced) composites which were tested at three different temperatures to determine the effect of temperature on material properties. The specific material systems tested were IM7/PEEK (0)8, (0, + or - 45, 90)s, (+ or - 30, 04)s, 25 vol. pct. (v/o) SiCp/Al, and 25 v/o SiCw/Al. RT material property results of IM7/PEEK were in good agreement with the predicted values, providing a measure of consolidation integrity attained during fabrication. Results of mechanical property tests indicated that modulus values at each test temperature were identical, whereas the strength (e.g., tensile, compressive, flexural, and shear) values were the same at -150 F, and RT, and gradually decreased as the test temperature was increased to 250 F. Similar trends in the strength values was also observed in discontinuous SiC/Al composites. These results indicate that the effect of temperature was more pronounced on the strength values than modulus values

ADZ: Analysis of the World Wide Web

The hardware and architecture approach to Smalltalk is defined not only by the refinement of architecture, but also by the important need for red-black trees [13]. After years of confirmed research into web browsers, we prove the under- standing of robots, which embodies the essential principles of interactive cryptography. In this paper we use amphibious communication to dis- confirm that suffix trees and systems can interact to answer this issue

Design, Simulation of Low Actuation RF MEMS Shunt Switches With Electromagnetic Characterization

Micro Electro Mechanical Systems (MEMS) is an integration of sensors, actuators, microstructures and microelectronics. Components of MEMS that comprises of moving sub milli-meter sized parts, capable of providing Radio Frequency (RF) functionality are collectively referred as RF MEMS. In this work, low actuation RF MEMS switches have been designed and simulated and they have also been analysed for electromagnetic characterization. The switches so analyzed show an actuation voltage of as low as 2V. The electromagnetic analysis gives an isolation of as high as 55-65dB and a very low insertion loss of 0.01dB. DOI: 10.17762/ijritcc2321-8169.15068

Vertex links and the Grushko decomposition

We develop an algorithm of polynomial time-complexity to construct the Grushko decomposition of groups belonging to a class of CAT(0)-cubical groups, typically amalgamated products of free groups over cyclic subgroups. We impose a strong connectivity condition on vertex links, first studied by Brady and Meier, to obtain our result.Comment: 12 pages, 6 figure

Composite materials for space applications

The objectives of the program were to: generate mechanical, thermal, and physical property test data for as-fabricated advanced materials; design and fabricate an accelerated thermal cycling chamber; and determine the effect of thermal cycling on thermomechanical properties and dimensional stability of composites. In the current program, extensive mechanical and thermophysical property tests of various organic matrix, metal matrix, glass matrix, and carbon-carbon composites were conducted, and a reliable database was constructed for spacecraft material selection. Material property results for the majority of the as-fabricated composites were consistent with the predicted values, providing a measure of consolidation integrity attained during fabrication. To determine the effect of thermal cycling on mechanical properties, microcracking, and thermal expansion behavior, approximately 500 composite specimens were exposed to 10,000 cycles between -150 and +150 F. These specimens were placed in a large (18 cu ft work space) thermal cycling chamber that was specially designed and fabricated to simulate one year low earth orbital (LEO) thermal cycling in 20 days. With this rate of thermal cycling, this is the largest thermal cycling unit in the country. Material property measurements of the thermal cycled organic matrix composite laminate specimens exhibited less than 24 percent decrease in strength, whereas, the remaining materials exhibited less than 8 percent decrease in strength. The thermal expansion response of each of the thermal cycled specimens revealed significant reduction in hysteresis and residual strain, and the average CTE values were close to the predicted values

Effect of Endowments on Gender Wage Differentials: A Decomposition Analysis for Indian Labour Market

The earning function clearly supports the existing evidence of the significant positive coefficients for education and the marginal wage effects are increasing with the level of education for both the genders. There are clear evidence of caste bias for males, location and regional bias for both the genders in earning. Our decomposition results show that endowment component which shows the existence of pre-market discrimination is smaller than the discrimination component. Discrimination explains 66.1 per cent of the lower wages of female individuals when compared to males. Discrimination component is the highest for the production workers (81.3 per cent) followed by professionals (77.6 per cent), agriculture/allied workers (77.4 per cent), clerical workers (65.9 per cent) and is least for sales/services workers (61.4 per cent). Gender wage discrimination is very high for the urban areas (86.3 per cent) than the rural settings (71.3 per cent). Large discrimination differences are a matter of concern for thepolicy makers.JEL Classifications: I21, J30, J3

Comparative Study Between Ultrasound Therapy with Combination of Elastic Band and Conventional Therapy for Anterior Shoulder Instability

Background: Shoulder joint has the greatest range of motion so shoulder instability occurs between 10-30% total populations.Objective: The purpose of the study is to investigate the effect of ultrasound therapy along with elastic band over conventional therapy in subjects with anterior shoulder instability. Study Design: Randomized clinical trials.Method: The study is randomized controlled study, the total subjects were ten for each group. The assessment of pain and ROM were taken before starting the treatment of both the groups. The patient were randomly assigned for both the group, assessment were taken on 0 day and 21 day of pain by VAS, ROM by goniometer.Result:The scores of variables VAS and ROM were improved significantly better in the subjects treated with ultrasound therapy and elastic bands.Conclusion: The study concludes that the elastic band exercise in combination with ultrasound therapy is more beneficial than the manual conventional therapy in shoulder instability condition

To Study the Effectiveness of Laser Therapy and G.D Maitland Mobilization in Adhesive Capsulitis Among 40-50 Years Age Group Male Patients

Background:Thestudy focused to make a comparative evaluation regarding the efficacy of laser therapy treatment with that of the Maitland mobilization technique in patients with adhesive capsulitis. Objective: Study to show the effectiveness of laser therapy and G.D Maitland mobilization in adhesive capsulitis. Methods:In this randomized controlled study, total subject 30participants were equally divided using random method in to two different treatment groups with each group having 15 patients each in each of the group namely GD Maitland Mobilization and the LASER therapy group. All the subjects were treated for 3 sessions per week for six weeks (total 18 sessions). The variable of the study include assessments of pain severity on Visual Analogue Scale (VAS), shoulder active ROM (flexion, extension, abduction), associated disability SPADI scores for pain and disability scales.nbsp The variable score were taken in the beginning of the study (day 0) and after 30 days and 90 days for both the group. Goniometric assessment of active ranges of shoulder movements were made for the range documentation of the study. Data of 30 subjects (only men) enrolled subjects were used for analysis. Results:In the study there are improvement in all shoulder parameters after treatment and in the follow up period compared to before treatment in both groups. Conclusion: though both treatment are effective in reducing the symptoms associated with adhesive capsulitis, the study concludes that G.D Maitland is more effective than Laser therapy at the 30 days documentation.nbs