scholarly journals Reliability of test battery

2020 ◽  
Vol 13 (2) ◽  
pp. 205979912091834
Author(s):  
Satyendra Nath Chakrabartty

After a brief review of methods for assessing the reliability of individual test, the article presents a method of obtaining reliability of a battery of tests where battery score could be defined as sum of weighted or unweighted scores of the component tests. Such battery reliability can be influenced significantly by method of selection of weights to arrive at the battery scores and methods of estimating reliability of component tests. Test reliability as per theoretical definition in terms of length of score vectors of two parallel tests and angle between such vectors in N-dimensional space also helps to find values of error score variance of the test fits well in estimation of battery reliability. Relationship between theoretically defined reliability rtt and split-half correlation rgh was established. For weighted battery score, a Lagrange multiplier-based solution for determination of weights is recommended with the use of reliability as per the theoretical definition. Weights found as above have the advantage that the battery score (Y) has minimum variance. Also, covariance between the battery score and the score of an individual test is a constant. Condition of battery score being equi-correlated with the standardized score of each constituent test was derived.

Author(s):  
Victor N. Semenov ◽  
Vitaly V. Volkov ◽  
Natalia V. Pereslytskikh

In this study, we proposed a new approach to assessing the processes of complexation in aqueous solutions using the example of the interaction of lead chloride with thiourea. The goal of this study was the investigation of processes of complexation in “PbCl2-N2H4CS” aqueous solutions and determination of the regions of dominance of thiourea coordination compounds, which are precursors during the deposition of lead sulphide films.Based on the diagrams and cross section lines of equal fractions constructed in three-dimensional space, the regions of dominance of all complex forms existing in the studied solution were found. Such a graphic image is the most informative, since it allows selection of the concentration ranges of the predominance of certain coordination compounds, especially thiourea complexes, which are precursors during the deposition of lead sulphide films. It was shown that an increase in the concentration of N2H4CS led to an increase in the total fraction of thiourea complexes: for a twofold excess of N2H4CS its fraction was 0.25, for a threefold excess it was 0.35, for a fourfold excess it was 0.5, for a fivefold excess it was 0.7.


2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Imam Setiadi ◽  
Dinda Rita K. Hartaja

Selection of the appropriate composition desalination units can be done with a variety of method approaches, one of the method is the Analytic Hierarchy Process. In determining the desalination unit with AHP method to consider is setting a goal, an alternative criteria and pairwise comparison. Research for the determination of the exact composition of the desalination unit in order to achieve sustainable drinking water suppy in coastal areas and small islands has been conducted. The results of the study are as follows, the energy demand of 50.83%, operator costs of 26.64%, maintenance costs of 14.13% and chemical requirement 8.4%. For an alternative composition desalination unit of RO 10 m3 / day is the best alternative composition with value of 59.61%, the composition of the next alternative is RO 20 m3/ day of 30.40% and the last alternative of the desalination unit composition is RO 120 m3/ day of 09.99%.Key words : Desalination, Mukti Stage Flash Composition, AHP


Kerntechnik ◽  
2008 ◽  
Vol 73 (3) ◽  
pp. 118-121
Author(s):  
T. Heinrich ◽  
L. Funke ◽  
M. Köhler ◽  
U.-K. Schkade ◽  
F. Ullrich ◽  
...  

2020 ◽  
pp. 73-75
Author(s):  
B.M. Bazrov ◽  
T.M. Gaynutdinov

The selection of technological bases is considered before the choice of the type of billet and the development of the route of the technological process. A technique is proposed for selecting the minimum number of sets of technological bases according to the criterion of equality in the cost price of manufacturing the part according to the principle of unity and combination of bases at this stage. Keywords: part, surface, coordinating size, accuracy, design and technological base, labor input, cost price. [email protected]


1994 ◽  
Vol 29 (1-2) ◽  
pp. 53-61
Author(s):  
Ben Chie Yen

Urban drainage models utilize hydraulics of different levels. Developing or selecting a model appropriate to a particular project is not an easy task. Not knowing the hydraulic principles and numerical techniques used in an existing model, users often misuse and abuse the model. Hydraulically, the use of the Saint-Venant equations is not always necessary. In many cases the kinematic wave equation is inadequate because of the backwater effect, whereas in designing sewers, often Manning's formula is adequate. The flow travel time provides a guide in selecting the computational time step At, which in turn, together with flow unsteadiness, helps in the selection of steady or unsteady flow routing. Often the noninertia model is the appropriate model for unsteady flow routing, whereas delivery curves are very useful for stepwise steady nonuniform flow routing and for determination of channel capacity.


Author(s):  
Yernar Zh Akimbayev ◽  
Zhumabek Kh Akhmetov ◽  
Murat S Kuanyshbaev ◽  
Arman T Abdykalykov ◽  
Rashid V Ibrayev

Studying the historical facts of past wars and armed conflicts and natural and man-made emergencies, today in the Republic of Kazakhstan one of the most important security issues is the preparation and organization of the evacuation of the population from possible dangerous zones, taking into account the emergence of new threats to the country’s security. The paper presents an algorithm for constructing universal scales of the distribution function of opportunities by types of support and rebuilding them into subject scales using display functions. The purpose of the paper is to determine the integral indicators characterizing the possibility of accommodation of the evacuated population and the impact on resources during relocation. On the subject scales of cities and districts of the region, indicators of the possibility of relocation of a certain amount of the evacuated population by types of support and indicators characterizing the impact on the district’s resources during resettlement of a certain amount of the evacuated population are determined. It was concluded that the use of integrated indicators allows the selection of areas to accommodate the evacuated population without the use of statistical data, in conditions of incomplete and inaccurate information. The presented method does not replace traditional methods based on classical methods of territory assessment by the level of life sustenance, but also allows their reasonable combination with the experience of specialists in this field, taking into account the incompleteness, uncertainty, and inconsistency of the initial data of the study area, which does not allow the application of existing methods.


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