• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.114-122
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• 2012

Vertical closed-loop ground source heat pump systems(GSHP) have been installed widely in Korea since it can extract moderate temperature level of geothermal heat in a small area. As a ground heat exchanger, a vertical closed -loop type with brine circulation is mostly preferred since it is simple and less harmful to ground environment. However, it requires a secondary heat exchange loop between the refrigerant in a heat pump and the brine. By adding a geothermal heat exchanger in the secondary heat exchange loop, circulation pumps should be attached and the temperature difference between refrigerant and ground is increased, which are important parts of performance degradation. In this paper, annual and seasonal performances of direct expansion(DX) geothermal heat pump were estimated mathematically as an alternative of classical indirect geothermal heat pump based on the annual performance evaluation. As results, DX geothermal heat pump showed 43% higher annual performance than the classical U-tube geothermal heat pump.

• Journal of radiological science and technology
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• v.39 no.3
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• pp.305-312
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• 2016

This study were compared with the direct measurement and indirect dose methods through various dose calculation in head and wrist. And, the modified equation was proposed considering equipment type, setting conditions, tube voltage, inherent filter, added filter and its accompanied back scatter factor. As a result, it decreased the error of the direct measurement than the existing dose calculation. Accordingly, diagnostic radiography patient dose comparison would become easier and radiogrphic exposure control and evaluation will become more efficient. The study findings are expected to be useful in patients' effective dose rate evaluation and dose reduction.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.16 no.1
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• pp.21-41
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• 2005

This study proposes the customer quality a parameter of service quality from a new perspective, develops and evaluation scale for it in relation to service business, analyzes and evaluates the its effect on service quality and performance. First, the concept of service quality and customer quality was investigated in the literatures, to find a basis for its relation to the quality of hotel service. However, previous 1) Among the service quality components, the strongest correlation exists between physical quality and service quality. 2) Hotel quality is most influenced by customer quality, followed by service provider quality and physical quality showing that when customer quality is incorporated as a prerequisite parameter if hotel quality it has the most effect on hotel quality, which is a new result. 3) Customer quality plays a significant indirect role via hotel quality on performance, and the physical quality and service provider quality offered to the customer at a hotel have more direct effect on performance, illustrating the difference in the effect on hotel quality depending on the component of hotel quality. 4) The evaluation of hotel quality and performance becomes more meaningful and valid only when customer quality is included as a prerequisite parameter of hotel quality to strongly interact with service provider quality 5) Comparative analysis of the different qualities according to the hotel class show a significant difference in customer quality, physical quality and service provider quality and performance between first-class and second-class hotels.

• Smart Structures and Systems
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• v.11 no.4
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• pp.365-386
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• 2013

Monitoring systems currently applied to concrete bridges include strain gauges, inclinometers, accelerometers and displacement transducers. In general, vertical displacements are one of the parameters that more often need to be assessed because their information reflects the overall response of the bridge span. However, the implementation of systems to continuously and directly observe vertical displacements is known to be difficult. On the other hand, strain gauges and inclinometers are easier to install, but their measurements provide no more than indirect information regarding the bridge deflection. In this context, taking advantage of the information collected through strain gauges and inclinometers, and the processing capabilities of current computers, a procedure to evaluate bridge girder deflections based on polynomial functions is presented. The procedure has been implemented in an existing software system - MENSUSMONITOR -, improving the flexibility in the data handling and enabling faster data processing by means of real time visualization capabilities. Benefiting from these features, a comprehensive analysis aiming at assessing the suitability of polynomial functions as an approximate solution for deflection curves, is presented. The effect of boundary conditions and the influence of the order of the polynomial functions on the accuracy of results are discussed. Some recommendations for further instrumentation plans are provided based on the results of the present analysis. This work is supported throughout by monitoring data collected from a laboratory beam model and two full-scale bridges.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.82-90
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• 2013

Concentration errors critically affect the performance of solar concentrator, so their evaluation is important to the concentrated solar power technology. However, the evaluation is very challenging because error sources are various and not easy to measure individually. Therefore, the integrated effect of concentration errors is often more interesting and useful for large-scale applications. In the present work, we analytically investigate and classify various concentration error sources and then explain that the effect of various concentration errors can be represented in terms of a root mean square value of reflector surface slope error. We present an indirect approach to assessing the reflector surface slope error by comparing solar flux measurement data with modeling calculations. We apply the approach for solar furnaces with different thermal capacity and investigate its advantages and disadvantages.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.479-486
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• 2021

This study aims to explore the relationships between strategic planning, strategic maneuverability, and firm performance in the current dynamic business environment. It employs a quantitative research method and reports on a survey, using a questionnaire, of service companies in Indonesia's oil and gas industry. Of the 337 companies selected by simple random sampling from a vendor database, responses were received from 70 companies. The analysis was performed using Partial Least Square Structural Equation Modeling and SmartPLS software. The analysis consisted of descriptive statistics, evaluation of the measurement model, evaluation of the structural model, and hypotheses testing. The results show that both strategic planning and strategic maneuverability have a positive relationship with firm performance. In addition, there is a positive relationship between strategic planning and firm performance through the mediating role of strategic maneuverability. The findings suggest that the organizational agility, organizational flexibility, and organizational responsiveness that constitute strategic maneuverability have a positive direct and indirect effect on firm performance, namely financial performance, customer performance, internal process performance, and learning and growth. This study contributes to the strategic management literature and the theory of maneuvers by providing empirical evidence on the relationship between strategic planning, strategic maneuverability, and firm performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.125-126
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• 2022

As environmental problems around the world become serious, Korea has also raised the greenhouse gas reduction in the building sector to 32.8% compared to 2018, and efforts to reduce carbon in buildings are expanding. Recently, research is being actively conducted to reduce carbon in the long term by expanding the scope of greenhouse gas indirect emissions (Scope3), and even within the domestic Green Standard for Energy and Environmental Design(G-SEED) by quantitatively evaluating the environmental impact of buildings during the entire life cycle. However, it is difficult to accurately evaluate the carbon emission of the transportation process by assuming the material transport distance in the evaluation of the Life Cycle Assessment(LCA). Therefore, in this study, the main building materials of the building were selected through case evaluation and the carbon emission of the material transport process was derived based on the actual transport distance, and this was compared and analyzed with the theoretical LCA results.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.261-267
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• 2011

The test fit has commonly used for the evaluation of the railbed condition, and indirect methods by using the compressional wave are also studied. the direct evaluation method by penetration test has not been studied. For the measurement of in-situ cone tip resistance of the railbed with minimizing the disturbance of the upper railbed. the cone penetrometer with the helical type outer rod(CPH) was developed. The outer rod, which has helical screw, is penetrated through the gravel layer and provides the reaction force for cone penetration testing. the cone tip resistances are measured by the mini cone penetrometer, where diameter is 15mm. For the developing the mini cone, strain gauge installation, circuit configuration, penetration rates and calibration process are considered. For the easy penetration of the screw rod in the field, the reaction force stepping plate and guide column are arranged. The screw rod are penetrated through the gravel layer. And the mini cone was pushed into the subgrade railbed at the penetration rate of 1mm/sec. The penetration test shows that the cone tip resistance increases along the depth. In addition, the subgrade condition is evaluated. This study demonstrates that the CPH may be effectively used for the evaluation of subgrade method any damage of the gravel layer.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.9_10 s.157
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• pp.1400-1412
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• 2006

As PB market segments into premium market, PBs were drawing attentions in terms of creating profits as well as a means to differentiate building up store identity. The purpose of this study makes a comparative study on the difference of consumer attitude formation process in discount store and home-shopping distribution channel which are recently on the upswing. This paper investigated the consumer's attitude formation on the private apparel brand. Subjects of this study were consumers in their $20s{\sim}40s$ who are main customer groups of PBs. The data were analyzed by Structural Equation Modeling and Multi-Group Analysis of Amos 5.0 to verify the difference of the path between store PB and premium PB. Following are the results of the study. Consumer attitude formation path on PB grades showed statistically noticeable difference. In discount store PB, store evaluation didn't directly influence on consumer attitude formation but showed indirect effect. On the other hand, in home shopping premium PB case, product evaluation directly influenced on consumer attitudes with store evaluation. Hedonic attitude dimension connected with behavioral attitude(purchase intention) revealed difference in path. Also consumer's evaluation on variables in model turned out to be different according to brand grade.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.16-22
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• 2003

The purpose of this study was to provide visual evaluation data in a workstation space when different lighting types were applied. For the performance evaluation, Radiance program was used for simulations, and the mock-up room(15.0x11.6x3m) was used for the actual test. The results of this study were as follows; 1) When the inidirect lighting simulation data using Radiance was compared with the actual data in a small workstation space, there was a 6.5% difference. Therefore, Radiance program was proved to be useful for the evaluation of lighting performance. 2) Higher light levels (higher light ratio (%)) were recorded in the straddled layout and lower light levels (lower light ratio (%)) were recorded in the centered layout condition in most cases. 3) Also, the results show that the indirect luminaires and the straddled layouts provide higher uniformity, whereas the direct luminaires and the centered layouts have lower uniformity.