• Journal of Mechanical Science and Technology
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• v.20 no.9
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• pp.1475-1482
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• 2006

Wet compression means the injection of water droplets into the compressor of gas turbines. This method decreases the compression work and increases the turbine output by decreasing the compressor exit temperature through the evaporation of water droplets inside the compressor. Researches on wet compression, up to now, have been focused on the thermodynamic analysis of wet compression where the decrease in exit flow temperature and compression work is demonstrated. This paper provides thermodynamic and aerodynamic analysis on wet compression in a centrifugal compressor for a microturbine. The meanline dry compression performance analysis of centrifugal compressor is coupled with the thermodynamic equation of wet compression to get the meanline performance of wet compression. The most influencing parameter in the analysis is the evaporative rate of water droplets. It is found that the impeller exit flow temperature and compression work decreases as the evaporative rate increases. And the exit flow angle decreases as the evaporative rate increases.

• Journal of the Korea Institute of Building Construction
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• v.13 no.4
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• pp.372-381
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• 2013

In the construction industry, a great deal of research has been focused on productivity improvement because a minor change in labor productivity can often make the difference between a profit and a loss. This study shows how productivity measurement methods can be applied in practice, step by step, to analyze and identify potential problems both in productivity and methods performance for masonry work. A work sampling technique was conducted to determine the nature and extent of an observable activity as an aid to measuring overall performance. Also, a method productivity delay model was used to identify non-productivity in individual cycle times. From the work sampling technique, it was found that the masonry crew had a Labor Utilization Factor of 47.1%, and from the videotape analysis, it was found that the material and dumpster location need to be adjusted to reduce the travelling distance. We have found that efforts to improve the productivity of masonry work should be focused almost exclusively on machine and labor delays, based on the result from the method productivity delay model.

• The Journal of Korean Academic Society of Nursing Education
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• v.20 no.4
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• pp.628-638
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• 2014

Purpose: This study identifies the relation among the essentials of fundamental nursing skills performance (EFNSP), work capability and stress from work experienced by new clinical nurses. Method: This is a cross-sectional descriptive study with a self-reported questionnaire. The subjects were 224 new clinical nurses employed by general hospitals having more than 400 beds. The data, collected from February 10 to March 7, 2014, were analyzed using descriptive statistics, t-tests, ANCOVA, Pearson's correlation analysis and hierarchical linear regression. Results: The highest frequency of EFNSP of new clinical nurses was vital sign measurement (4.74, ${\pm}.89$) and the lowest frequency of performance was Basic CPR & defibrillator application (1.81, ${\pm}.94$). There were significant positive correlations between frequency and confidence of EFNSP (r=.64, p<.001), frequency and work capability (r=.34, p<.001), and confidence of EFNSP and work capability (r=.48, p<.001), but negative correlation stress from work and work capability (r=-.17, p=.009). General characteristics, stress from work, frequency and confidence in EFNSP and stress from work explain 25.1% of work capability. Conclusion: This result suggests the importance of EFNSP education in nursing schools and availability of opportunities to practice EFNSP during the post-graduation waiting period until assignment to a hospital.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.230-238
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• 2021

This study sought to understand the mediating effect of job enthusiasm in relation to work-life balance and job performance of hospital workers. The data collected through a self-contained survey using structured questionnaires for employees of medical institutions in Busan and South Gyeongsang Province were analyzed using SPSS 26.0 and Process Macro programs. As a result of the analysis, job performance and non-role performance were the most influenced by passion (+), and work-life balance was evaluated as a factor that increased job enthusiasm. In addition, work-life balance directly influenced job performance, but indirectly influenced job performance as a medium. In particular, the work-life balance and the relationship between performance other than roles were fully mediated. In order to improve the job performance of hospital workers at the organizational level, it is necessary to increase job enthusiasm, which means that efforts are needed to establish an organizational culture that values work-life balance.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.436-446
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• 2015

Work-family interface including work-family conflict and work-family enrichment has an effect on organizational performance such as job satisfaction and organizational commitment. This empirical research mainly investigated influence of family-friendly organizational culture on work-family interface and organizational performance. Three key variables apply for this research : work-family interface, organizational performance and family-friendly organizational culture. A total 750 questionnaire was collected from female managers in various companies for hypothesis testing. The empirical analysis shows that reducing work-family conflict and enhancing work-family enrichment positively contribute to job satisfaction and organizational commitment. The Family-friendly organizational culture plays a moderating role between work-family interface and organizational performance. As a result, the findings support the fact that family-friendly organizational culture impact on organizational performance through work-family balance.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.6
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• pp.94-102
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• 2001

The thermodynamic second law analysis, which means available energy or exergy analysis, for the indicated performance of Otto cycle engine has been carried out. Each operating process of the engine is simplified and modeled into the thermodynamic cycle. The calculation of the lost work and exergy through each process has been done with the thermodynamic relations and experimental data. The experimental data were measured from the test of single cylinder Otto cycle engine which operated at 2500 rpm, WOT(Wide Open Throttle) and MBT(Minimum advanced spark timing for Best Torque) condition with different fuels: gasoline, methanol and mixture of butane-methanol called M90. Experimental data such as cylinder pressure, air and fuel flow rate, exhaust gas temperature, inlet gas temperature and etc. were used for the analysis. The proposed model and procedure of the analysis are verified through the comparison of the work done in the study with experimental results. The calculated results show that the greatest lost work is generated during combustion process. And the lost work during expansion, exhaust, compression and induction process follows in order.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.82-89
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• 1998

This study was carried out to investigate working time, performance, and to predict performance that related to the factor of forest road in earth work using excavator. It was found that the real working time was 503 minutes in a day. The ratio of real working time and allowance per total working time was approximately 85.7% and 14.3% individually. The rate of soil movement(Sm) to net working time was 38.6%, and earth cutting(Ec) was 32.5%. According to performance analysis, performance of earth work using excavator($0.8m^3$) in straight part was 1.4 times larger than curve part and rock work using excavator($0.8m^3$) which had breaker in straight was 9.1 times larger than earth work using excavator($0.8m^3$) which had bucket. Performance of earth work using excavator($1.0m^3$) was 1.3 times larger than using excavator($0.8m^3$) in straight and curve part. Working performance in earth work using excavator($0.8m^3$) was influenced by the conditions of radius of curve, width of roadway, slope gradient. It is not influenced by diameter and number of root stock.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.509-519
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• 2021

The purpose of this study is to understand the mediating effect of self-leadership in the process of understanding the effects of nursing job performance and job satisfaction in the nursing work environment perceived by nurses. In this study, nurses who worked for more than one year at three general hospitals located in Province A. Total of 225 data were used for the final analysis. Date analyzed using the SPSS 22.0 program by t-test, ANOVA, Pearson's correlation coefficient and hierarchical regression analysis. Self-leadership was found to play a partial mediating role in the relationship between nursing work environment and nursing job performance(z=4.30, p<.001) and between nursing work environment and job satisfaction(z=3.70, p<.001). Therefore, in order to improve nursing job performance and job satisfaction, it will be necessary to establish a management plan that can improve the nursing work environment and improve self-leadership.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05b
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• pp.77-79
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• 2011

As residents and building owners demand maintenance that is required to achieve sustainable building performance, efficient building management methods are required. Even though the demand for maintenance systems is increasing, current maintenance work for high-rise buildings mostly uses conventional ropes and gondolas that pose a high risk of accidents and exhibit poor performance and efficiency. Thus, there is an urgent need to develop an automation robot system that can reduce accidents and improve the maintenance efficiency of the conventional high-rise building façade maintenance system. As a preceding work for the development of an automation robot system, this study classified and analyzed the work processes of actual construction sites and proposed basic techniques for the work mechanisms of the robot system by investigating the motions of cleaning workers.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.230-236
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• 2009

Double-front construction machinery, which was designed for complicated tasks, requires intelligent systems that can provide the quantitative work analysis needed to determine effective work procedures and that can provide operational and cognitive support for operators. Construction work environments are extremely complicated, however, and this makes state identification difficult. We therefore defined primitive static states (PSS) that are determined using on-off data for the lever inputs and manipulator loads for each part of the grapple and front and that are completely independent of the various environmental conditions and operator skill levels. To confirm the usefulness of PSS, we performed experiments with a demolition task by using our virtual reality simulator. We confirmed that PSS could robustly and accurately identify the work states and that untrained skills could be easily inferred from the PSS-based work analysis. We also confirmed in skill-training experiments that advice information using PSS-based skill analysis greatly improved work performance. We thus confirmed that PSS can adequately identify work states and are useful for work analysis and skill improvement.