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The purpose of this study is to achieve lower and lower temperature as infrared sensors works faster and better used for space application. For getting good quality images from space, the infrared sensors are need to keep in cryogenic temperature. Cooling to cryogenic temperatures is necessary for space-borne sensors used for space applications. Infrared sensors work faster or better at lower temperatures. It is the need for time to achieve lower and lower temperatures.

This study presents the investigation of the critical Stirling cryocooler parameters that influence the cold end temperature. In the paper, the design approach, the dimensions gained through thermal analysis, experimental procedure and testing results are discussed.

The effect of parameters such as multilayer insulation, helium gas charging pressure, compressor input voltage and cooling load was investigated. The performance of gold-plated and aluminized multilayer insulation is checked. The tests were done with multilayer insulation covering inside and outside the Perspex cover.

By using aluminized multilayer insulation inside and outside the Perspex cover, the improvement of 16 K in cool-down temperature was achieved. The cryocooler is charged with helium gas. The pressure varies between 14 and 18 bar. The optimum cooling is obtained for 17 bar gas pressure. The piston stroke increased as the compressor voltage increased, resulting in total helium gas compression. The optimum cool-down temperature was attained at 85 V.

The cryocooler is designed to achieve the cool-down temperature of 2 W cooling load at 100 K. The lowest cool-down temperature recorded was 105 K at a 2 W cooling load. Multilayer insulation is the major item that keeps the thermal radiation from the sun from reaching the copper tip.

The success of construction projects can be indicated by measuring their performance. For effective project performance (PP), the successful execution of a construction projects is very important. A systematic review of the literature on performance areas and performance assessment models was undertaken. The purpose of this paper is to develop a mathematical formulation for construction PP areas to suit the Indian context by modifying the current project quarterback rating (PQR) model.

Based on the literature, the PQR model has not been validated for suitability in the Indian context. To validate the PQR model and modify the same for the Indian context, a survey instrument was used to collect data on performance areas and a multivariate data analysis technique was carried out to develop a modified model. Delphi technique was used to assign the weights for each performance metric in performance areas.

This study concluded the importance of three additional performance areas, namely, productivity, stakeholder satisfaction and environment for assessing PP for Indian construction projects. It also identified the interrelationship between the performance areas and the PP.

The developed modified PQR model (MPQR) will guide the concerned stakeholders to take corrective actions for improving the performance of construction projects.

The MPQR proposed in this paper covers ten areas and is a comprehensive single score that can be used to benchmark and compare performance over different projects to achieve continuous improvement.

Research on caregiving has been considering the positive effects experienced by the mothers of children with disabilities. This paper aims to examine whether positive perceptions mediate the relationships between coping strategies used and psychological well-being among mothers of children with intellectual disabilities.

The study opted for a quantitative approach that includes a correlation research design to examine the relationships between the variables of coping, positive perceptions and well-being among mothers of children with intellectual disabilities attending special schools in the metropolitan city Bengaluru, India. The four-factor structure of Brief COPE examined were active avoidance coping, problem-focussed coping, positive coping and religious-denial coping. “Positive perceptions” refer to the positive contributions for the mother from the experiences of raising a child with intellectual disability. Mediation analysis explored the relationship between the variables.

Problem-focussed coping was the most commonly reported coping factor and was associated with higher levels of well-being. Active-avoidance coping was the least commonly reported coping strategy. Positive perceptions partially mediated the relationship between the four coping factors and maternal well-being. These findings indicate that positive maternal perceptions have important implications for the employment of effective coping strategies that are associated with enhancement of psychological well-being.

The focus on positive perceptions would help in understanding the use of coping strategies and planning of support services or interventions. The positive mental health of mothers paves the way for positive developments in the child’s physical and psychological health.