• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.201-208
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• 2012

Purpose: This study was conducted to develop a vegetable transplanting robot which transplants seedlings from a nursery tray to a plant pot using its four fingers. Method: The robot consists of the transplanting part, nursery tray moving part, plant pot moving part, main frame and controller. Two moving parts are controlled by the photo sensor and servo motor. The transplanting part was composed with two components; transporting device using E-MY2H(SMC Corp., Japan) for controlling finger position accurately and finger for transplanting the seedling. Results: Head lettuce using the transplanting robot was transplanted in 21 days after sowing based upon the seed shape measurement and removing examination. The optimal finger shape was thin pin type because it caused minimum damage to the roots of seedlings. Conclusions: The four inclined pin type was applied to remove the seedlings from the nursery tray. In addition, the transplanting capacity of the developed robot was 2800 pots per hour and the rate of success was 99% and above.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.179-180
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• 2008

In this paper, the variable tendency piezoelectric constant and resonance characteristics piezoelectric ceramics due to the electric field is studied. The practical application of piezoelectric ceramics is not only applied in field of small signal. For example, in case of an ultrasonic motor, $120{\sim}130Vrms$ of driving voltage is needed and that of an piezoelectric pump, $200{\sim}220Vrms$ of voltage is required. Therefore, to examine the characteristics of piezoelectric ceramics in large signal contributes to reducing the susceptibility to the multifarious application and securing the ease of the production of control circuit. These contributions may be connected to the expansion of industrial application. We fabricated disk-type piezoelectric ceramic samples by using conventional method and measured the resonance characteristics of these samples under from low to high voltage driving conditions. According to increasing the value of the input voltage, we measured the resonance frequency of the piezoelectric ceramic, and inquired into the cause of these phenomena.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.12
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• pp.9-20
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• 2012

This paper proposes the efficiency optimization control of interior permanent magnet synchronous motor(IPMSM) drive using series connected-fuzzy neural network PI(SC-FNPI) controller. The PI controller is generally used to control IPMSM drive in industrial field. However, the PI controller has problem which is falling control performance about parameter variation such as command speed, load torque and inertia due to fixed gain of PI controller. Therefore, to improve performance of PI controller, this paper proposes SC-FNPI controller adjusted input of PI controller by FNN controller according to operating conditions. Also, this paper proposes efficiency optimization control which is improving efficiency with minimize loss. The SC-FNPI controller proposed in this paper is compared control performance with conventional FNN and PI controller about command speed, load torque and inertia variation. And the efficiency optimization control is compared with $i_d=0$ control about loss and efficiency. The SC-FNPI controller proposed in this paper shows more excellent control performance for rising time, overshoot and steady-state error. Also efficiency optimization control is increased efficiency by reducing loss.

• Proceedings of the KAIS Fall Conference
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• 2012.05b
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• pp.775-777
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• 2012

차세대전동차는 직접구동모터(DDM : Direct Drive Motor) 방식으로 기존에 사용하던 기어박스를 없애는 등, 연결부품을 제거함으로써 고장률을 줄여 기존차량 대비 30% 이상 신뢰도를 향상하도록 개발하였다. 그러나, 단순히 모터 자체 만을 변경함으로써 신뢰도를 향상시켰다고 보기는 어렵고, 시스템 차원에서 전동차 내 타 구성품과의 인터페이스를 살펴보고, 정량적인 분석을 통해서 신뢰도가 어느 정도 향상되었는지 살펴볼 필요가 있다. 신규차량일 경우, 기존차량대비 어느 정도로 신뢰도가 향상되었는지를 입증하고자 주행시험을 실시하는데 전동차에 신뢰성 이론을 적용하기 위해서는 크게 목표설정, 신뢰도예측, 신뢰도입증의 3단계 작업이 진행되며, 신뢰도 예측은 주요장치를 구성하고 있는 부품단위의 고장률을 이용하여 시스템의 신뢰도를 예측하고, 신뢰도 목표치를 만족하는지를 분석하는 것이며, 신뢰도 입증은 예측한대로 시스템이 구축되었는지 확인하는 것이다. 본 논문에서는 차세대 전동차에서 설정한 목표신뢰도를 만족시키기 위해 수행한 업무에 대하여 논하고자 한다.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.824-827
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• 2010

본 논문은 전동형 모터의 Rotor의 자동 성형을 위한 자동화된 주조기 개발에 대한 결과이다. 개발된 자동화된 Rotor 전용 주조기는 수평형에 비해 금형의 크기가 약 1/2정도 이므로 금형 체결력이 반감되고, 기계 구조는 매우 작아진다. 그리고 Al용탕이 사출되는 과정에서 Spool -> Runner -> Gate -> Cavity(제품)에 이르기까지의 Runner를 최소화하여 재용융을 위한 에너지의 비용 절감을 할 수가 있다. 금형 구조가 간단하므로 금형비가 저렴하여 다품종 소량생산에 매우 유리하다. 개발제품은 수직형 구조로 알루미늄 용탕의 윗면의 공기가 금형의 유로 상측에 위치하므로 공기(gas)가 먼저 배출되어 사출(주조)후 Rotor 성형부에 남아 있는 기포가 최소화된다. 그러므로 충진도가 높아진다. Rotor 코아(규소강)가 크더라도 수직형은 금형내에 삽입(Inset)하기가 쉽고 또한, 제품의 착탈 부위와 사출부위가 다르기 때문에 작업성, 안전성이 우수하고 생산성이 매우 높다. 수직형은 충진 밀도가 매우 높고 밀도가 균일하기 때문 Rotor의 회전 소음, 진동에 대한 품질이 매우 우수하다. 따라서 고효율, 고품질의 전동모터 Rotor 제품 생산에 매우 효과적인 장비라 할 수 있다.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.595-598
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• 2010

본 연구의 목적은 뇌졸중으로 인한 만성 편마비 환자를 대상으로 발에 시지각 자극을 적용하여 균형과 보행에 관한 운동기능에 미치는 효과를 알아보고자 하였다. 6개월 이상 된 편마비 환자 16명이 연구에 참여하였고, 무작위로 실험군(EG) 10명과 대조군(CG) 10명으로 구분하였다. 두 군 모두 기본적인 물리치료를 적용하였고 실험군은 정적균형도구인 Tetrax Multiple System을 이용하여 발목에 감각되먹임 시지각 자극을 매회 30분, 4주간 주 3회 실시하였다. 운동 중재 전과 후의 운동기능에 해당하는 균형(TUG), 보행(DGI)을 측적하여 본 연구의 효과를 비교하였다. 실험군에서 정적 균형, TUG, 그리고 동적 균형지수(DGI) 지수는 중재 전후 통계적으로 유의한 차이를 나타냈고(p<.05), 실험, 대조군간 전후의 변화율에서도 유의한 차이가 나타났다(p<.05). 대조군에서는 DGI 만 중재 전후 통계적으로 유의한 차이가 나타났다. 순수하게 유산소 운동만을 실시하였다. 통계처리 방법으로 전 후 차이를 검증하기 위하여 대응표본 t 검정을 실시하였고 대조군과의 차이 검증을 위하여 독립표본 t 검정을 실시하였다. 모든 통계적 유의수준은 0.05로 하였다. 본 연구에서는 편마비 환자에게 흥미를 촉진하고 운동 기능 회복의 효과를 강화할 수 있는 감각 되먹임이 동반된 시지각 자극을 적용하여 균형 및 보행기능의 향상을 얻을 수 있었고, 차후 연구는 장기간의 추적 관찰 연구가 지속되어야 하고 발목 뿐만 아니라 다른 관절에서의 비교연구가 필요할 것이다.

• Korean Management Science Review
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• v.31 no.4
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• pp.117-134
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• 2014

Today the concept of corporate social responsibility has become an essential element for coexistence of corporations and the society. In this study the impact of four responsibilities of business organizations proposed by Archie Carroll (economic, legal, ethical, and discretionary) on customer loyalty through the mediating effect of trust and company-consumer identification is analyzed. A questionnaire survey was conducted for four well-known Korean companies (Dong Suh Food, LG Household and Health Care, Samsung Electronics, and Hyundai Motor). After factor analysis, legal and ethical responsibilities were grouped as the same factor, thus three social responsibilities were finally used for hypotheses testing. Major findings were as follows: First, economic responsibilities had positive impact on honesty trust, professionalism trust, favorableness trust, and company-consumer identification, Second, legal/ethical responsibilities were found to have significant effects on honesty trust, favorableness trust, and company-consumer identification. Third, in the case of discretionary responsibilities, professionalism trust, favorableness trust, and company-consumer identification were revealed to have a significant positive relationship. Fourth, only two trust variables (honesty and professionalism) and company-consumer identification had positive influence on the loyalty of customers. These findings are expected to help decision makers to set up corporate objectives and choose action items for corporate social responsibility. At the last part, implications of the study and future research directions were discussed.

• The Journal of Industrial Distribution & Business
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• v.7 no.1
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• pp.11-14
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• 2016

Purpose - The study aims to show the successful application of Six Sigma in software companies for process improvement. Research design, data and methodology - A mixed methodology has been used which include both qualitative and quantitative research. In the qualitative research methodology part, a detailed and comprehensive literature study have been carried out. The literature study consists of articles, books, web materials, discussion forms and others. In the quantitative research methodology part, interviews have been conducted. Results - Six sigma is the practical application of a theoretical statistical measurement that equates to 3.4 defects per million opportunities -a position of practically zero defects for any process or service. Initially originating in Motorola Inc. in 1985 as a response to drastic quality improvement pressures from the threat of Japanese competition, it quickly gained many followers particularly G.E., Allied Signal, Ford Motor Company etc. and more recently attentions have shifted to service environments. There are still some problems and misconceptions existed about the applicability of Six Sigma in software companies. Conclusions - The paper concludes that Six Sigma can bring large benefits for software companies too. Furthermore, software companies have already started to implement Six Sigma approach, like Ericsson, Tata Consultancy Service, etc.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.21-29
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• 2013

The short circuit and overload is presented by main cause of electrical fire. However, 85% of the fan directly connected the outlet box without switch in total 110 fans as a research in manufacturing industries. In installation direction of vertical type fans which was placed on the horizontal surface, only 39 vertical type fans were placed on vertical surface and 71 fans were placed on the horizontal type. The installation direction of the fans warns of the risk of the fire hazard due to the motor stall to the user manual of the maker. However, it is the representative nonconformity example of construction which the people or builder disregards. In addition, the condition of ground connection with the earth leakage prevention was investigated in grounding of 5 fans, non-grounding of 105 fans. The double insulation structure is generally used for small fan and it can't connect ground wire as electric plug of non-grounding type. However, industrial iron fan needs ground wire for electric leakage and to protect against electric shock.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.2
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• pp.107-115
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• 2003

PMSM(permanent magnet synchronous motor) are widely used in industrial and home appliance because of their high torque to inertia ratio, superior power density, and high efficiency For the high control performance, accurate information of rotor position Is essential. In recent, sensorless algorithms are much studied due to high cost problem of position sensor and low reliability in harsh environment. In the proposed method, a differential linkage flux is used for the estimation of rotor position. The differential magnetic field flux is calculated by the voltage equations and measured phase current without any integration and differential calculus. Instead of linkage flux calculation with differential operation, a new mathematical differential method is introduced by a-$\beta$ transformation. The proposed novel position sensorless speed control scheme is verified through experimental results.