• International Journal of Fuzzy Logic and Intelligent Systems
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• v.10 no.1
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• pp.65-72
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• 2010

For developing navigation system of total hip arthroplasty (THA) and evaluating hip joint kinematics, 3-D pose position of the femur and acetabulum in the pelvic coordinate system has been quantified. The pelvic coordinate system is determined by manually indicating pelvic landmarks in multidetector-row computed tomography (MDCT) images. It includes intra- and inter-observer variability, and may result in a variability of THA operation or diagnosis. To reduce the variability of pelvic coordinate system determination, this paper proposes an automated method in MDCT images. The proposed method determines pelvic coordinate system automatically by detecting pelvic landmarks on anterior pelvic plane (APP) from MDCT images. The method calibrates pelvic pose by using silhouette images to suppress the affect of pelvic pose change. As a result of comparing with manual determination, the proposed method determined the coordinate system with a mean displacement of $2.6\;{\pm}\;1.6$ mm and a mean angle error of $0.78\;{\pm}\;0.34$ deg on 5 THA subjects. For changes of pelvic pose position within 10 deg, standard deviation of displacement was 3.7 mm, and of pose was 1.28 deg. We confirmed the proposed method was robust for pelvic pose changes.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.648-658
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• 2018

Regarding the fact that wind power forecast accuracy is gradually improved as time is approaching, this paper proposes a two-stage rolling dispatch approach based on model predictive control (MPC), which contains an intra-day rolling optimal scheme and a real-time rolling base point tracing scheme. The scheduled output of the intra-day rolling scheme is set as the reference output, and the real-time rolling scheme is based on MPC which includes the leading rolling optimization and lagging feedback correction strategy. On the basis of the latest measured thermal unit output feedback, the closed-loop optimization is formed to correct the power deviation timely, making the unit output smoother, thus reducing the costs of power adjustment and promoting wind power accommodation. We adopt chance constraint to describe forecasts uncertainty. Then for reflecting the increasing prediction precision as well as the power dispatcher's rising expected satisfaction degree with reliable system operation, we set the confidence level of reserve constraints at different timescales as the incremental vector. The expectation of up/down reserve shortage is proposed to assess the adequacy of the upward/downward reserve. The studies executed on the modified IEEE RTS system demonstrate the effectiveness of the proposed approach.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.688-690
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• 2017

Reduction of breakdown voltage is serious short channel effect (SCE) by shrink of channel length. The SCE occurred in on-state transistor raises limitation of operation range of transistor. The deviation of breakdown voltage for doping concentration is investigated with structural parameters of sub-10 nm double gate (DG) MOSFET in this paper. To analyze this, thermionic and tunneling current are derived from analytical potential distribution, and breakdown voltage is defined as drain voltage when the sum of two currents is $10{\mu}A$. As a result, breakdown voltage increases with increase of doping concentration. Breakdown voltage decreases by reduction of channel length. In order to solve this problem, it is found that silicon and oxide thicknesses should be kept very small. In particular, as contributions of tunneling current increases, breakdown voltage increases.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.633-636
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• 2017

This thesis is about the evaluation method of field uniformity for radiated immunity test of vehicle component. Radiated immunity test is to find out whether a EUT has enough immunity or hold normal operation during applied electromagnetic interference. Field Uniformity(FU) measurement is essential for generate uniform field on DUT and Harness. But Standard of Radiated Immunity(RI) test for vehicle component based on ISO 11452-2 has not been specified a Field Uniformity(FU). So compared and analyzed with other standard which is defined by a specified a Field Uniformity. As a result, deviation occurs in the difference test condition and test method. In this thesis, proposal new measurement method of field uniformity that is considered test conditions of ISO 11452-2 and check the validity through actual test.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.3
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• pp.95-106
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• 2000

The load frequency control of power system is one of important subjects in view of system operation and control. That is even though the rapid load disturbances were applied to the given power system, the stable and reliable power should be supplied to the users, converging unconditionally and rapidly the frequency deviations and the tie-line power flow one on each area into allowable boundary limits. Nonetheless of such needs, if the internal parameter perturbation and the sudden load variation were given, the unstable phenomenal of power system can be often brought out because of the large frequency deviation and the unsuppressible power line one. Therefore, it is desirable to design the robust neuro-fuzzy controller which can stabilize effectively the given power system as soon as possible. In this paper the robust neuro-fuzzy controller was proposed and applied to control of load frequency over multi-area power system. The architecture and algorithm of a designed NFC(Neuro-Fuzzy Controller) were consist of fuzzy controller and neural network for auto tuning of fuzzy controller. The adaptively learned antecedent and consequent parameters of membership functions in fuzzy controller were acquired from the steepest gradient method for error-back propagation algorithm. The performances of the resultant NFC, that is, the steady-state deviations of frequency and tie-line power flow and the related dynamics, were investigated and analyzed in detail by being applied to the load frequency control of multi-area power system, when the perturbations of predetermined internal parameters. Through the simulation results tried variously in this paper for disturbances of internal parameters and external stepwise load stepwise load changes, the superiorities of the proposed NFC in robustness and adaptive rapidity to the conventional controllers were proved.

• Journal of dental hygiene science
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• v.20 no.1
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• pp.51-58
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• 2020

Background: The present study aimed to provide basic data to establish a foundation for efficient operation of the organization by identifying the effects of factors related to moral sensitivity and psychological well-being on job engagement of clinical dental hygienists. Methods: This cross-sectional survey consisted of self-administration questionnaires. After the approval by the Institutional Review Board, a survey was conducted from September 2019 to November 2019, targeting dental hygienists with clinical experience of 1 year or more. A total of 189 questionnaires were analyzed using SPSS 18.0 for Windows. The data were analyzed using average standard deviation, t-test, one-way analysis of variance, Scheffe test, Pearson's correlation analysis, and multiple regression analysis. Results: According to job-related characteristics, higher job engagement was associated with more amount of clinical experience, less turnover intention, higher positions, and occasional job fatigue. Job engagement was improved by increasing moral sensitivity and psychological well-being of clinical dental hygienists. The factors affecting job engagement revealed that along with clinical career, the sub-areas of job engagement, namely turnover intention, moral sensitivity, and psychological well-being had statistically significant influence on job engagement and the explanatory power of the model was approximately 44.8%. Conclusion: Joy of working as a clinical dental hygienist, clinical career, turnover intention, moral sensitivity, and psychological well-being were confirmed as influencing factors that affected job engagement of clinical dental hygienists. It is necessary to establish an effective plan to improve job engagement by increasing moral sensitivity and psychological well-being of clinical dental hygienists.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.823-835
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• 2010

The research aimed to measure the efficiency of using multi stores in a foodservice company using by DEA (data envelopment analysis) which is a new management science technique. The study also attempted to identify relevant variables affecting DEA efficiency in order to suggest methods for improving efficiency. The data were collected from 148 contract foodservice operations, which were operated in similar fashion in October 2009. The DEA efficiency was calculated as an output-oriented BCC Model. Sales, and CSI (customer satisfaction index) were used as output variables whereas food cost, labor cost, and management expense were used as input variables to calculate the DEA efficiency. Operation process variables of the unit consisted of the were consist of ratio of regular employee, ratio of housekeeper, meal counts, meal price, food cost per meal, contract period, number of menu items, forecasting accuracy, order accuracy, inventory turnover, use of processed food, deviation of food cost, number of new menus, and number of events. According to the BCC score and profitability, units were classified into four groups: High efficiency-high profitability (HEHP), High efficiency-low profitability (HELP), Low efficiency-high profitability (LEHP), and Low efficiency-low profitability (LELP). The HEHP group contained 54 units, which mostly contracted management fee type and had a high meal price. The units were also very large and, served three meals. Twenty of the units were operated with high labor cost: most of these were factories and hospitals. The LEHP group contained 20 units, that were mainly office stores of large scale and medium price. Fifty-four LELP group had a low meal price. A high performance group must have high efficiency, profitability, and satisfaction. The BCC score was over 0.969, the meal price was over 4,116 won, the food cost was over 2,077 won, and meal counts per month were over 10,212 meals.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.525-538
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• 2016

This study is to investigate the effect of the amusement factor and the motive of participation in skin-scuba class on the satisfaction with university life with the university students participating in the skin-scuba class and to provide the practical research data for the development of the marine sports, for the proper operation of skin-scuba class, and for the leisure life which the university students may lack. For these purposes, technical statistics between questions were disposed in order to grasp the average and standard deviation on each variables, exploratory factor analysis and reliability analysis were conducted for the reliability and validity of the scale, and correlation analysis and multiple regression analysis were conducted to test the casuality of amusement factor, the motive of participation in skin-scuba class and the satisfaction with university life as the research methods. Research results showed that it was confirmed that the amusement factor and the motive of participation in skin-scuba class act as the important variables in the satisfaction with university life and it was predicted that the motive of participation in skin-scuba class and the amusement factor had interrelation with parameter. Therefore, a variety of programs reflecting the amusement factors should motivate the university students to particiapte in the skin-scuba class to increase the satisfaction with university life and to encourage the re-participation of students.

• Journal of Information Technology and Architecture
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• v.10 no.4
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• pp.479-496
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• 2013

Today, a corporate and the government is making significant investments in informatization in order to enhance competitiveness however, question on the outcome of information-oriented investment has continuously been posed and in order to resolve such problems, the technique of Enterprise Architecture (EA) Despite such fact, in the case of the central administrative institute, even if the EA maturity standard has continuously improved through continuous investment when compared to the past without deviation between institutes, the establishment of EA and the work utilization of EA compared to the management competence still is analyzed to be relatively weak. This study completed the preliminary feasibility study in 2012 for Korea Customs Service which has been appointed as the representative institute that best utilizes EA in the field of information operation and evaluation field in the 2010 EA Maturity Evaluation and it can become a case study that can contribute to more continuous development and improvement of other public institute EA by introducing the performance of EA-based 4th Korean National Customs Information Network which has entered into total reconstruction in 2013 and by identifying the implications of EA performance arising from such.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.83-88
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• 2006

Many applications in the area of location-based services and personal navigation require nowadays the location determination of a user not only in outdoor environment but also indoor. To locate a person or object in a building, systems that use either infrared, ultrasonic or radio signals, and visible light for optical tracking have been developed. The use of WiFi for location determination has the advantage that no transmitters or receivers have to be installed in the building like in the case of infrared and ultrasonic based location systems. WiFi positioning technology adopts IEEE802.11x standard, by observing the radio signals from access points installed inside a building. These access points can be found nowadays in our daily environment, e.g. in many office buildings, public spaces and in urban areas. The principle of operation of location determination using WiFi signals is based on the measurement of the signal strengths to the surrounding available access points at a mobile terminal (e.g. PDA, notebook PC). An estimate of the location of the terminal is then obtained on the basis of these measurements and a signal propagation model inside the building. The signal propagation model can be obtained using simulations or with prior calibration measurements at known locations in an offline phase. The most common location determination approach is based on signal propagation patterns, namely WiFi fingerprinting. In this paper the underlying technology is briefly reviewed followed by an investigation of two WiFi positioning systems. Testing of the system is performed in two localization test beds, one at the Vienna University of Technology and the second at the Hong Kong Polytechnic University. First test showed that the trajectory of a moving user could be obtained with a standard deviation of about ${\pm}$ 3 m.