Space Shuttle entry thermal testing techniques

1978 ◽  
Author(s):  
H.J. Zuo ◽  
M.W. Price ◽  
R.D. Griffin ◽  
R.A. Andrews ◽  
G.M. Janowski

The II-VI semiconducting alloys, such as mercury zinc telluride (MZT), have become the materials of choice for numerous infrared detection applications. However, compositional inhomogeneities and crystallographic imperfections adversly affect the performance of MZT infrared detectors. One source of imperfections in MZT is gravity-induced convection during directional solidification. Crystal growth experiments conducted in space should minimize gravity-induced convection and thereby the density of related crystallographic defects. The limited amount of time available during Space Shuttle experiments and the need for a sample of uniform composition requires the elimination of the initial composition transient which occurs in directionally solidified alloys. One method of eluding this initial transient involves directionally solidifying a portion of the sample and then quenching the remainder prior to the space experiment. During the space experiment, the MZT sample is back-melted to exactly the point at which directional solidification was stopped on earth. The directional solidification process then continues.


Author(s):  
Jeffrey W. McCandless ◽  
Robert S. McCann ◽  
Bruce R. Hilty
Keyword(s):  

2020 ◽  
Vol 5 (1) ◽  
pp. 61
Author(s):  
Vadlan Febrian ◽  
Muhamad Rizki Ramadhan ◽  
Muhammad Faisal ◽  
Aries Saifudin

In this employee payroll application, if there is an error program there will be a loss for employees and the company. Losses for employees, if this application program error occurs then the salary reduction will experience delays due to the difficulty in the process of calculating employee salaries and employees will be late in receiving salaries. Losses for the company, if there is an error program in this application, the company will suffer losses if the employee wants a salary reduction quickly but the company cannot calculate quickly and accurately. In solving this problem, the authors use the black box testing method. Black box testing method is a test that sees the results of execution through test data and ensures the function of the software. Black box testing method has several testing techniques, namely Sample Testing, Boundary Value Analysis, Equivalence Partitions and others. From the testing techniques that have been mentioned, we use the Equivalence Partitions testing technique. Equivalence Partitions are tests that refer to data entry on the employee payroll application form, input will be tested and then put together based on the test function, both valid and invalid values. The expected results of this test are a payroll system for employees who are computerized, have standard rules in the process of developing the program so that it is easy to develop and maintain, and can minimize errors in processing salary calculations for employees.


2016 ◽  
Vol 5 (2) ◽  
pp. 365
Author(s):  
Mohamad Suparno

The background of this study is the low results of social studies class V SD Negeri 010 Silikuan Hulu Kecamatan Ukui. This is evidenced by of 26 students only 11 (41.67%), which reached KKM, to research the learning improvement by implementing cooperative learning model Jigsaw. This research is a class act who do as much as two cycles. The collection of data in research adalag with the testing techniques. The study states that the implementation of cooperative learning model jigsaw can improve learning outcomes IPS, it is seen from: the average student learning outcomes which increased 20.25% from the average value of the basic score is 69.58 into 83.67 at UH the first cycle, and the average value UH second cycle increased 31.50% from the average score of 69.58 into 91.50 basis. The percentage of classical completeness achievement has been as expected. Which, on the basis of completeness klasikalnya score is 41.67% with the category is not exhaustive and the UH first cycle increased to 87.50% with the category completely, then at UH second cycle increased to 91.67% with the category completely.


2012 ◽  
Vol 2 (8) ◽  
pp. 12-14 ◽  
Author(s):  
H. P. Singh H. P. Singh ◽  
◽  
R. P. S. Shaktawat R. P. S. Shaktawat ◽  
Durga Singh Durga Singh ◽  
S. C. Srivastava S. C. Srivastava

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