• Steel and Composite Structures
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• v.27 no.2
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• pp.229-242
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• 2018

High strength steel is widely used in industrial applications to improve the load-bearing capacity and reduce the overall weight and cost. To take advantage of the benefits of this type of steel in construction, an innovative hybrid fabricated member consisting of high strength steel tubes welded to mild steel plates has recently been developed. Component-scale uniaxial and multiaxial cyclic experiments have been conducted with simultaneous constant or varying axial compression loads using a multi-axial substructure testing facility. The structural interaction of high strength steel tubes with mild steel plates is investigated in terms of member capacity, strength and stiffness deterioration and the development of plastic hinges. The deterioration parameters of hybrid specimens are calibrated and compared against those of conventional steel specimens. Effect of varying axial force and loading direction on the hysteretic deterioration model, failure modes and axial shortening is also studied. Plate and tube elements in hybrid members interact such that the high strength steel is kept within its ultimate strain range to prevent sudden fracture due to its low ultimate to yield strain ratio while the ductile performance of plate governs the global failure mechanism. High strength material also significantly reduces the axial shortening in columns which prevents undesirable frame deformations.

• Journal of Applied Reliability
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• v.11 no.3
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• pp.251-265
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• 2011

Low-noise amplifier(LNA) is a component that amplifies the signal while lowering the noise figure of high-frequency signal. LNA holds a very important position in RF system so that it is widely used for telecommunication. Electro static discharge(ESD) is the most common cause of malfunction for low-powered components, such as Large Scale Integration and IC type LNA is weak in ESD. This thesis studies static effect of communication LNA. It analyzes ESD effect, which occurs within LNA circuit, and describes testing standard and methods. In order to find out LNA's susceptiblity to electro static, two well-recognized communication IC type LNA models were selected to be tested. Then static-induced malfunction was carefully analyzed and it suggests architectural problem and improvement from the LNA's ESD point of view.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.309-313
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• 2015

If the present universe is slightly open then pre-inflation curvature would appear as a cosmic dark-flow component of the CMB dipole moment. We summarize current cosmological constraints on this cosmic dark flow and analyze the possible constraints on parameters characterizing the pre-inflating universe in an inflation model with a present-day very slightly open ${\Lambda}CDM$ cosmology. We employ an analytic model to show that for a broad class of inflation-generating effective potentials, the simple requirement that the observed dipole moment represents the pre-inflation curvature as it enters the horizon allows one to set upper and lower limits on the magnitude and wavelength scale of pre-inflation fluctuations in the inflaton field and the curvature parameter of the pre-inflation universe, as a function of the fraction of the total initial energy density in the inflaton field. We estimate that if the current CMB dipole is a universal dark flow (or if it is near the upper limit set by the Planck Collaboration) then the present constraints on ${\Lambda}CDM$ cosmological parameters imply rather small curvature ${\Omega}_k{\sim}0.1$ for the pre-inflating universe for a broad range of the fraction of the total energy in the inflaton field at the onset of inflation. Such small pre-inflation curvature might be indicative of open-inflation models in which there are two epochs of inflation.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.103.2-103.2
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• 2012

NGC 2024 FIR 6 is a star formation site in Orion and may contain a hypercompact H II region, FIR 6c, and a low-mass protostar, FIR 6n. The FIR 6 region was observed in the water maser line at 22 GHz and the methanol class I maser lines at 44, 95, and 133 GHz, using KVN in the single-dish telescope mode. The water maser spectra displayed several velocity components and month-scale time variabilities. Most of the velocity components may be associated with FIR 6n while one component was associated with FIR 4, another young stellar object in the 22 GHz beam. A typical life time of the water-maser velocity-components is about 8 months. The components showed velocity fluctuations with a typical drift rate of about 0.01 km/s/day. The methanol class I masers were detected toward FIR 6. The methanol emission is confined within a narrow range around the systemic velocity of the FIR 6 cloud core. The methanol masers did not show a detectable time-variability. The methanol masers suggest the existence of shocks driven by either the expanding H II region of FIR 6c or the outflow of FIR 6n.

• The Research Journal of the Costume Culture
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• v.11 no.6
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• pp.793-807
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• 2003

The purpose of this study is to show the component and anticipation factors of loyalty and word-of-mouth. Specifically, hypothesis is that trust in a salesperson will influence satisfaction with the salesperson, and the store. And the satisfactions with the salesperson and the store will influence the loyalty to the salesperson and the store. Another hypothesis is that loyalty to a salesperson and a store will influence word-of-mouth. Scale items used in this study were selected from developed scales and were adapted to conforming to the selling situation in the service setting. Factor analysis and Cronbach's alpha test were accomplished. A total of 703 samples was used to test the hypotheses. The primary method of statistical analysis to test the hypotheses was a structural equation modeling on LISREL 8.3. The results of the study are as follows: First, trust had an influence on satisfaction with a salesperson and a store. Second, the results suggested that satisfaction with the salesperson and the store influences loyalty to the salesperson and the store. Finally, loyalty to the salesperson and the store influenced word-of-mouth, as predicted.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.4
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• pp.335-342
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• 2000

This study is to integrate and to analyzegraphic and attribute data in features which should be preceding for the ITS construction. A 1:5000 scale map as a national basemap was used and was checked for feasibility. For the convenience of position confirmation, the analysis component was developed and was linked to addresses. Also, the attribute information was considered on the shortest route, and optimal route was selected by investigating traffic volumes on main crossroads depending on the time zone. The optimal route could be selected by analyzing user's demands, position and statistical data, and the position information could be provided efficiently by combining the graphic information with the land register information.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.190-198
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• 2002

Full scale durability test in the laboratory is an essential of any fatigue life evaluation of components or structures of the automotive vehicle. Component testing is particularly important in today's highly competitive industries where the design to reduce weight and production costs must be balanced with the necessity to avoid expensive service failure. Generally, hydraulic road simulator is used to carry out the fatigue test and the vibration test. In this paper, the algorithm and software to realize the real road profile are developed. The operation software for simultaneously controlled multi-axial road simulator is developed and the input and output data are displayed window based PC controller in the real time. Futhermore, the software to generate the real road profile are developed. The validity of the software are verified by applying the belgian road, the city road, the highway, and the gravel road. The results of the above experiment show that the real road profiles are realized well after 10th iteration.

• Korea Journal of Hospital Management
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• v.4 no.2
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• pp.1-20
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• 1999

Objectives: Quality of Working Life(QWL) is a set of employee's physical, mental conditions which are perceived at their work. Most employees and managers are concerned about the quality of working life as a strategy for improving organizational effectiveness. The purpose of this study is to investigate the relationship between QWL and organizational effectiveness of employees at the general hospital. Methods : Data were collected by self-administered questionnaires at the general hospital in Kyunggi-Do. Survey was conducted to 675 workers. QWL was measured by using 5 items from the scale developed by Walton(1973). Organizational effectiveness was measured by measuring organizational commitment, intention of job-shift, and job satisfaction. Results: The recognitions to each component of QWL were significantly different by socio-demographic characteristics such as sex, age, education levels and working duration. Also, QWL were significantly different by types of organizational culture. Multiple regression analysis and multiple logistic regression analysis were applied to find the relationship of QWL and organizational effectiveness. As a result, job-pride, compensation, working condition, human relationship and development showed significant relationship with organizational effectiveness. Conclusions: These results show that QWL is significantly related to organizational effectiveness. So we expect that this result will be used as basic informations for management and motivation of employees at the general hospital.

• 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.

• The KSFM Journal of Fluid Machinery
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• v.13 no.4
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• pp.18-24
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• 2010

For testing large-capacity pumps, the accurate flow rate measurement is needed in the test loop. As a measuring method of flow rate, venturi tube is recommended due to its low pressure loss. However, upstream disturbance of loop component such as a valve has an effect upon the accuracy of flow rate measurement. For controlling flow rate in case of high flow rate and large-scale piping system, a butterfly-type valve is generally used due to its compactness. However, a butterfly valve disturbs downstream flow by generating turbulence, cavities, or abrupt pressure change. In this study, the effect of downstream disturbance of butterfly valve on the flow rate measurement using a venturi tube is investigated. Test loop consists of circulation pump, reservoir, butterfly valve, venturi tube, and reference flow meter. The test is conducted with regard to a different valve opening angle of butterfly valve. According to the valve opening angle, the uncertainty of flow rate measurement is investigated.