• International Journal of Air-Conditioning and Refrigeration
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• v.16 no.2
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• pp.37-43
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• 2008

The air and water flow distributions are experimentally studied for a round header - ten flat tube configuration. Three different inlet orientation modes (parallel, normal, vertical) were investigated. Tests were conducted with downward flow configuration for the mass flux from 70 to $130kg/m^2s$, quality from 0.2 to 0.6, non-dimensional protrusion depth (h/D) from 0,0 to 0.5. It is shown that, for almost all the test conditions, vertical inlet yielded the best flow distribution, followed by normal and parallel inlet. Possible explanation is provided using flow visualization results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.66-69
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• 1989

After reviewing previous work done on two piezoelectric thin films(PZT, ZnO), ZnO thin piezofim of 1-3UM is fabricated by sputtering on the different substrates(i. e., P+Si/N-Si, SiO2/P+Si/ N-Si, Al/SiO2/ P+Si/ N+Si). The result shows that ZnO piezofilm on the Al has the best c-axis orientation. One of applications for the ZnO piezofilm as an microvalve to control liquid flow is introduced, and which can be controlled electrically and remotely.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.50-56
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• 2004

The directional ability of an automobile has an influence on driver directly, and hence it must be given most priority. Alignment factors of automobile such as the camber, caster and toe directly affect the directional ability of a vehicle. The above mentioned factors are determined by the pose of interlinks in the assembly of an automobile front chassis module. Measuring the position of center point of ball joints in the front lower arm is very difficult. A method to determine this position is suggested in this paper. Pose estimation for front chassis module and dimensional evaluation to find the rotational characteristics of front lower arm were developed based on fundamental geometric techniques. To interpret the inspection data obtained for front chassis module, 3-D best fit method is needed. The best fit method determines the relationship between the nominal design coordinate system and the corresponding feature coordinate system. The least squares method based on singular value decomposition is used in this paper.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.329-339
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• 2011

The purpose of this study was to compare the effects of service failure magnitude on perceived justice, positive emotion, and revisit intention at restaurants between a collectivist culture(Korea) and an individualistic culture(United States). The results showed that the higher a customer's perception of service failure magnitude, the lower the perceived recovery justices in both cultures. The distributive, procedural, and interactional justices had a favorable effect on positive emotions in both cultures. Other findings revealed that interactional justice was the best predictor of revisit intention in Korea, while distributive justice was the best determinant of revisit intention in the United States. This research suggests that global restaurant managers need to understand how cultural orientation influences consumer perceptions of service failures in order to develop a highly targeted and effective service recovery.

• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.647-658
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• 2017

This study aims to explore the relative influences of covert narcissism and evaluative concerns perfectionism on SNS addiction tendency, and the mediating effect of evaluative concerns perfectionism in the influence of covert narcissism on SNS addiction tendency of undergraduates. The results of this study can be summarized in the following. First, control failure and disturbance of adaptive, avoidance of negative emotion, and virtual life orientation and withdrawal were best accounted for by exploitation/self-centeredness. On the other hand, absorption and tolerance was best accounted for by hypersensitivity/vulnerability in undergraduates. Also, SNS addiction tendency was accounted for by only socially prescribed perfectionism of evaluative concerns perfectionism. Second, evaluative concerns perfectionism partially mediated the relations between covert narcissism and absorption and tolerance and between covert narcissism and virtual life orientation and withdrawal, while it didn't mediate the relations between covert narcissism and control failure and disturbance of adaptive and between covert narcissism and avoidance of negative emotion.

• Land and Housing Review
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• v.13 no.1
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• pp.113-129
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• 2022

A building's eco-friendliness is directly related to various values including the life cycle cost of a building. However, the conventional architectural design method has a limitation in that it cannot create an optimized case according to the surrounding environmental conditions. Therefore, the purpose of this research is to present a design assistance tool that can review planning cases optimized for the environmental conditions of the building site in the planning stage of architectural production. To achieve the purpose of the study, an algorithm for realizing 3D modeling of the region and analysis of the solar environment was produced based on the site contours, building, and road information from the digital topographic map provided by the National Geographic Information Institute. To examine the validity of the developed algorithm, a comparative experiment was conducted targeting the elevation direction of the existing building. As a result, it was found that the optimal elevation direction selected by the algorithm can receive higher insolation compared to the front facade of the main building.

• Korea Journal of Hospital Management
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• v.1 no.1
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• pp.108-135
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• 1996

This paper investigates the current feature of management strategy of hospitals in Korea, and examines the relationships between adoption of a particular strategic orientation and the hospitals environmental and organizational characteristics, strategic behaviors and management improvement activities, and financial performance. Data were collected from CEOs of 88 hospitals among 650 hospitals for a 13.5% response rate using the self-administered questionnaire by mail survey. The major findings that obtained are as follows: 1. Only 37.2% of response hospitals carried out strategic planning, Most of these hospitals established the first strategic planning in 1991(81.3%) and renovated strategic planning by 4 or 5 years(56.3%), and modified strategic planning with flexibility(59.4%). Most strategic plans were documented, but informalized(68.8%). And only 29.0% of these hospitals had independent planning division. 2. Hospital services that CEOs assessed rank ordered for their impact on profitability are as follows: i)diagnostic ultrasound facility, computerized tomography scanner, obstetric inpatient unit, therapeutic X-ray, and physical therapy at present. ii)diagnostic ultrasound facility, physical therapy, computerized tomography scanner, emergency department, and health screening at future. And the services rank ordered that CEOs hoped to introduce are as follows: emergency department, physical therapy, health screening, volunteer services, and computerized tomography scanner. 3. Using a typology developed by Miles and Snow(l978), the strategic orientation of response hospitals are shifting significantly from defenders in the past to analyzers in the present, and to prospectors in the future(p<.01). 4. With regard to hospital environmental and organizational characteristics such as ownership, physician training, location, bed size, and hospital management training career and specialty of CEOs, the four strategic orientation archetypes varied not significantly. But, hospitals with a analyser orientation in the present and a reactor orientation in the future perceived competition significantly higher than the other three archetypes(p<.05). 5. The four archetypes rank ordered in terms of appling strategic behaviors and management improvement activities are as follows: prospector, analyzer, reactor, and defender. 6. The four archetypes differed significantly in terms of their financial performance using revenue per bed(p<.05). Reactors and prospectors in terms of total revenue per bed, prospectors in terms of outpatient revenue per bed, and reactors and prospectors in terms of inpatient revenue per bed had the best performance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.155-160
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• 2002

Recently, the development of aerospace and automobile industries has brought new technological challenges, rebated to the growing complexity of products and the new geometry of the models. High speed milling with a 5-Axis milling machine has been widely used fur 3D sculptured surface parts. When turbine blades are machined by a 5-axis milling, their thin and cantilever shape causes vibrations, deflections and twists. Therefore, the surface roughness and the waviness of the workpiece are not good. In this paper, the effects of cutter orientation and the lead/tilt angle used to machine turbine blades with a 5-axis high speed ball end-milling were investigated to improve geometric accuracy and surface integrity. The experiments were performed using a lead/tilt angle of 15$^{\circ}$ to the workpiece with four cutter directions such as horizontal outward, horizontal inward, vertical outward, and vortical inward directions. Workpiece deflection, surface roughness and the machined surface were all measured with various cutter orientations such as cutting directions, and lead/tilt angle. The results show that the best cutting strategy for machining turbine blades with a 5-axis milling is horizontal inward direction with a tilt angle.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.11 s.170
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• pp.1929-1939
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• 1999

This paper presents a neural network approach, which was named PRONET, to 3D object recognition and pose calculation. 3D objects are represented using a set of centroidal profile patterns that describe the boundary of the 2D views taken from evenly distributed view points. PRONET consists of the training stage and the execution stage. In the training stage, a three-layer feed-forward neural network is trained with the centroidal profile patterns using an error back-propagation method. In the execution stage, by matching a centroidal profile pattern of the given image with the best fitting centroidal profile pattern using the neural network, the identity and approximate orientation of the real object, such as a workpiece in arbitrary pose, are obtained. In the matching procedure, line-to-line correspondence between image features and 3D CAD features are also obtained. An iterative model posing method then calculates the more exact pose of the object based on initial orientation and correspondence.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.535-540
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• 1994

Thin film magnet was fabricated by radio frequency magnetron sputtering using $Nd_13/(Fe.Co)_{70}B_{17}$ alloy target and magnetic properties were investigated according to sputtering conditions from the metallurgical point of view. we could obtain the best preferred orientation of $Nd_2Fe_{14}B$ phase at substrate temperatures between $450^{\circ}C$ and $460^{\circ}C$ with the input power 150W, and thin films had the anisotropic magnetic properties. But, as the thickness of thin film increased, the c-axis orientation gradually tended to be disordered and magnetic properties also become isotropic. Just like Nd-Fe-B meltspun ribbon, the microstructure of thin film magnet was consisted of very find cell shaped $Nd_2Fe_{14}B$ phase and the second phase along grain boundary. While, domain structure showed maze patterns whose magnetic easy axis was was perpendicular to film plane of thin film. It was concluded from these results that the perpendicualr anisotropy in magnetization was attributed to the perpendicular alignment of very find $Nd_2Fe_{14}B$ grains in thin film.