• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.1-8
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• 2016

Current sensors are used widely in the fields of current control, monitoring, and measuring. They have become more popular with the increasing demand for smart grids in a power network, generation of renewable energy, electric cars, and hybrid cars. Although open loop Hall effect current sensors have merits, such as low cost, small size, and weight, they have low accuracy. This paper describes the design and fabrication of a 300A open loop current sensor that has high accuracy and temperature performance. The core of the current sensor was calculated numerically and the signal conditioning circuits were designed using circuit analysis software. The characteristics of the manufactured open loop current sensor of 300 A class was measured at currents up to 300 A. According to the test of the current sensor, the accuracy error and linearity error were 0.75% and 0.19%, respectively. When the temperature compensation was carried out with the relevant circuit, the temperature coefficients were less than $0.012%/^{\circ}C$ at temperatures between $-25^{\circ}C$ and $85^{\circ}C$.

• Journal of Global Scholars of Marketing Science
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• v.15 no.2
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• pp.27-48
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• 2005

This study analyzed the structural elements of transformational leadership on hotel employees job satisfaction and organizational identification, and inquired into how moderating variables such as demographical characteristics and the features of hotels affect transformational leadership. The ultimate purpose of this study was to provide managerial implications to hotel business operators and hotel employees. The main results of this study are as follows; According to the result of factor analysis on transformational leadership and hotel employees job satisfaction, 18 variables were derived as two factors 'obliging leadership' & 'vision leadership' factor in the area of transformational leadership, and 31 variables were derived as four factors 'welfare and work environment', 'ability display and job stability', 'colleague relationship and job performance' and 'company policy' factor. Second, stepwise regression analysis on whether the type of transformational leadership at hotels has a significant effect on employees job satisfaction & organizational identification, 'vision leadership' and job satisfaction and the both 'vision leadership' & 'obliging leadership' among the types of transformational leadership appeared to have a significant effect on hotel employees organizational identification. Third, One-Way ANOVA and t-test in order to examine significant difference in the type of transformational leadership according to demographical characteristics and general characteristics, statistically significant difference was found according to income level, the current position, work experience, the type of hotel operation and the experience of job change.

• Journal of Broadcast Engineering
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• v.11 no.1 s.30
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• pp.116-129
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• 2006

The progress of data transmission technology through the Internet has spread a variety of realistic contents. One of such contents is multi-view video that is acquired from multiple camera sensors. In general, the multi-view video processing requires encoders and decoders as many as the number of cameras, and thus the processing complexity results in difficulties of practical implementation. To solve for this problem, this paper considers a simple multi-view system utilizing a single encoder and a single decoder. In the encoder side, input multi-view YUV sequences are combined on GOP units by a video mixer. Then, the mixed sequence is compressed by a single H.264/AVC encoder. The decoding is composed of a single decoder and a scheduler controling the decoding process. The goal of the scheduler is to assign approximately identical number of decoded frames to each view sequence by estimating the decoder utilization of a Gap and subsequently applying frame skip algorithms. Furthermore, in the frame skip, efficient frame selection algorithms are studied for H.264/AVC baseline and main profiles based upon a cost function that is related to perceived video quality. Our proposed method has been performed on various multi-view test sequences adopted by MPEG 3DAV. Experimental results show that approximately identical decoder utilization is achieved for each view sequence so that each view sequence is fairly displayed. As well, the performance of the proposed method is examined in terms of bit-rate and PSNR using a rate-distortion curve.

• The KIPS Transactions:PartD
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• v.10D no.5
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• pp.793-804
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• 2003

In the latest, it's increasing an applied technology to be related with growth of industry circles. It's one of them a software to be used in industry circles. and It's most important part to apply an industrial equipment, so software to take charge of major part is indicative performance of quipment. At this time, it's inspired an evaluation and measurement of software quality to have within industrial equipment, and it's forming the research and development by the inside and outside of the country. For this, it's constructed a valuation metric to be based on ISO/IEC 12119, the International Standard for general the terms desired of quality of software and ISO/IEC 9126-2, the International Standard of the terms valuation of qualify for evaluation and measure, and for this accomplishment, It has been designed and developed industrial software international standard compatible approval system which approve a quality based on quality test result of industrial software using the ISO/IEC 14598-6 that international standard for organization of evaluation module.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.481-492
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• 2018

The steel-plate concrete composite beam is composed of a steel plate, concrete and shear connector to combine two inhomogeneous materials. In general, the steel plate is assembled by welding an existing composite beam. In this study, the SPC beam was composed of folding steel plates and concrete, without a headed stud. The folding steel plate was assembled by a high strength bolt instead of welding. To improve the workability in a field construction, a hat-shaped cap was attached to the junction with a slab. Monotonic load testing under two points was conducted under displacement control mode to analyze the flexural strength of the SPC beam using a cap as the shear connector. Five specimens with shear connector types, protrusion length, and different thickness of steel plates were constructed and tested. The experimental results were analyzed through the relationship between the shear strength ratio and flexural strength in KBC 2009. The test results showed a shear strength ratio of more than 40 %. In the case of using a cap-like specimen as the shear connector, the flexural strength was 70% of the value calculated as a fully composite beam. In addition, the cap showed a smaller shear strength than the stud, but the cap served as a shear connection. When the thickness of the steel plate was taken as a variable, the steel plate exhibited a bending strength of approximately 70% compared to a fully formed steel plate, and exhibited similar deformation performance. Local buckling occurred due to incomplete composite behavior, but local buckling occurred at a 5% higher strength for a relatively thick steel plate. The buckling width also decreased by 15%.

• The Korean Nurse
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• v.37 no.4
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• pp.58-71
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• 1998

The purpose of this study was to contribute the improvement of nursing staff development by implementing of effective and organized orientation program using the measure of effectiveness in the application of preceptor program with the reduction of the time of New entry nurse orientation. The subjects were comprised of 116 new entry nurses(59 new entry nurses were employed at June, 1996 and 57 at May & July, 1997) and 79 preceptors, who were in charge of new entry nurse orientation at 1997. These date were collected from June 18, 1996 to August 29, 1997. The characteristics of questionairs applied in this study were general characteristics(7 questions), knowledge of nursing care(138 questions); attitude toward her profession(40 questions) and the degree of satisfaction for the program(5 questions). The questionnairs were developed by the researchers of Asan Medical Center. The Check-list for basic nursing skill were used for the measurement of nursing skill which was developed by nursing department of AMC. The data were analyzed for the mean, standard deviation, difference of mean, ANOV A & t-test. The results of this study are as follows : 1) The changes in knowledge of nursing care : After three months of training the difference of mean between before and after the orientation was higher than the result of two month period training. However, the result was insignificant(p= .469). 2) Performance in nursing practice : Two month period orientation was more effective than three-month training period, however, the statistical significance can not be reached than 3 month period, which resulted in insignificant difference(p=.150). 3) The change in attitude toward her profession : After three-month of orientation, the difference of mean between before and after the orientation was higher than 2 month period orientation, which resulted in significant difference (p=.000). 4) The degree of satisfaction for the program with the time of new entry nurse orientation : After two-month of orientation, the mean of points was 2.57 where the score is higher than 3 month period with mean of 2.30. It resulted in significant difference(p=.000).

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.21 no.3
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• pp.174-181
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• 2010

Objectives: To identify the factors affecting long-term adherence to methylphenidate treatment in children with attention-deficit hyperactivity disorder (ADHD). Methods: A retrospective medical record review of 239 ADHD patients (mean age $9.3{\pm}2.6$ years, range 6.0-17.4 years) who had visited the child and adolescent psychiatry clinic at a university hospital, in Seoul, Korea from March 2005 to February 2008. Subjects were diagnosed as ADHD based on the criteria set forth in the Diagnostic and Statistical Manual of Mental Disorders 4th edition, text revision version (DSM-IV-TR) and underwent neuropsychological tests including the continuous performance test (CPT). Treatment discontinuation was defined as the last prescription date when the medication possession rate (MPR) became less than 0.80. Subjects were divided into three groups and labeled as Group I, non-adherence without pharmacotherapy, Group II, non-adherence with short-term pharmacotherapy, and Group III, adherence with long-term pharmacotherapy. Results: Ninety (37.7%) patients were grouped as non-adherent (Groups I+II) and 149 (62.3%) as adherent (Group III). The adherence group exhibited lower intelligence, higher symptom severity, and a higher number of comorbid psychiatric disorders than controls. The use of stimulants was significantly associated with long-term adherence to treatment. Additionally, the duration of interval between the date of the first visit and the date of the first prescription was positively associated with long-term adherence. Conclusion: About two-thirds of patients diagnosed as ADHD adhered to the treatment six months after the first visit. With respect to patient evaluation and the development of treatment strategies, factors affecting early drop-out and longer follow-up must be considered.

• The Korean Journal of Emergency Medical Services
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• v.15 no.1
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• pp.37-46
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• 2011

Purpose : This study is equivalence experiment performed to test practice effects between experimental group from both left and right direction of mannequin and control group having practice from only right direction in cardiopulmonary resuscitation education. Methods : Subject of the research were total 71 elementary and middle school teachers in J province who had not experience to have cardiopulmonary resuscitation. They were divided into experimental group of 35 participants who practiced cardiopulmonary resuscitation from both right and left direction of mannequin on Dec. 27, 2009 and control group of 36 participants who performed cardiopulmonary resuscitation from only right direction of mannequin on Dec. 28, 2009. Collected data were analyzed by SPSS/PC+(version 14.0). Results : 1. There was no statistically significant difference by sex among general characteristics of the subjects. 2. According to the quality of chest compression performed from the right direction of mannequin, experimental group showed better results in proper depth (time), insufficient depth (time), too lowered compression position (time) and inexact position (time) than control group(p<.05). In the quality of chest compression from the left side of mannequin, experimental group performed better results in proper depth (time), insufficient depth (time), inexact compression position (time) and mean chest compression depth(mm) than control group(p<.05) and also in more left-centered compression position (time) than control group(p<.001). 3. The quality of chest compression by experimental group, the right side of mannequin was superior in proper depth (time) to the left side of mannequin (p<.001) and showed better results in insufficient depth (time) and chest compression/recoil rate (p<.05). According to the quality of chest compression by control group, the right side of mannequin showed superior results in proper depth (time), insufficient depth (time), too left-centered compression position (time) and mean chest compression depth (mm) (p<.05) to the left side of mannequin. Conclusion : The group having practice from both right and left sides of mannequin was superior in the quality of chest compression to the group having practice from only right side of mannequin. How to practice cardiopulmonary resuscitation from both right and left sides of mannequin can be recommended and practice from left side of mannequin is also useful.

• Journal of Ocean Engineering and Technology
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• v.28 no.2
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• pp.152-159
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• 2014

KRISO(Korea Research Institute of Ships & Ocean Engineering) designed and manufactured a pilot mining robot called "MineRo" in 2012. MineRo is composed of four track modules. In general, much time and money are needed for deep-sea tests. Therefore, a numerical analysis to predict the dynamic behaviors has to be performed before a deep-sea test. In the numerical analysis, the information about the mining robot and soil properties are the most important factors to analyze the driving performance and dynamic response of MineRo. A terra-mechanics model of extremely cohesive soft soil is implemented in the form of the relationships between the normal pressure and sinkage, and between the shear stress and shear displacement. It is possible to acquire information about MineRo from the CAD model in the design phase. The Wong model is applied to the terra-mechanics model. This model is necessary to acquire many soil coefficients for a numerical analysis. However, in soil testing, the amount of soil property data obtained is limited. Moreover, it is difficult to analyze all of the cases for the many soil coefficients. In this paper, the dynamic behaviors of MineRo are analyzed according to the driving velocity, steering ratio, and variable extremely cohesive soft soil properties using a table of orthogonal arrays. The dynamic responses of MineRo are the turning radius, sinkage, and slip ratio. The relationships between the dynamic responses and variable soil properties are derived for MineRo.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.11-18
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• 2013

Cement concrete pavement offers long-term service life and excellent applicability for heavy traffic. It is easier to purchase and more durable and economical than the asphalt pavement. However, it is difficult to repair and rehabilitate compared to the asphalt pavement when it comes to the maintenance problem. Since the crack is the main reason of the damage of concrete pavement, it is necessary to control the early and long-term crack in the concrete pavement. In this experimental study, the basic performance tests have been carried out to investigate the effect of hybrid fibers which were composed of micro fibers with small diameter and high aspect ratio and macro fibers with large diameter and low aspect ratio on the concrete pavement, in which lower water ratio and larger aggregates were used compared to the general concrete mixture. The test results showed that the flexural strength and toughness of concrete pavement mixture have been increased with the use of hybrid fibers in the concrete pavement mixture, even though they were less effective compared to the normal concrete mixture. It was found that the hybrid fibers were effective to control the early shrinkage of the concrete pavement which is one of the main reasons of the damage in the concrete pavement.