소형 수문용 랙-피니언의 접촉 피로수명

권순만(Soon-man Kwon) 한국생산제조학회 2017 한국생산제조학회지 Vol.26 No.3

Gate-lifting devices in small- to mid-sized sluice gates mostly employ the mechanical roller rack pinion (RRP) system. This RRP system, which consists of a rack-bar and a pinion, transforms a rotation motion into a linear one. The rack-bar has a series of roller trains that mesh with the pinion. In this study, we adopt an exact involute-trochoid tooth profile of the pinion to obtain a higher contact fatigue strength using the profile modification coefficient. Further, we determine the contact forces and investigate Hertz contact stresses to predict the pitting life of the pinion according to varying the shape design parameters. The results indicate that the design fatigue life of an RRP system for sluice gate can be achieved only when the design value of the profile modification coefficient reaches or exceeds a certain level.

유전자 알고리즘을 이용한 원판 캠의 비 유막두께 최적화

권순만(Soon-Man Kwon),김창현(Chang Hyun Kim),남형철(Hyoungchul Nam),신중호(Joong-Ho Shin) 대한기계학회 2008 大韓機械學會論文集A Vol.32 No.11

The rate of wear of cam followers in a valve train system is mainly a function of contact stress between the cam and the follower, sliding velocity and hydrodynamic film thickness between the two mating surfaces. The wear or surface fatigue can be reduced by maximizing the elastohydrodynamic film thickness. In this paper, an attempt has been made to estimate the optimal specific film thickness of cam-follower system quantitatively. A general TES polynomial function with real values of exponents is developed and genetic algorithm (GA) is used as optimization techniques for maximizing the minimum specific film thickness. The optimization programs enumerate values of the exponents for synthesis of cam displacement curves. The results show that the minimum film thickness can be increased considerably, e.g. approximately 7% in this paper.

RRP 시스템을 이용한 sprocket 치형설계

권순만(Soon-man Kwon) 한국생산제조학회 2014 한국생산제조시스템학회 학술발표대회 논문집 Vol.2014 No.9(1)

유전자 알고리즘을 이용한 원판 캠의 비 유막두께 최적화

권순만(Soon-Man Kwon),김창현(Chang Hyun Kim),남형철(Hyoungchul Nam),신중호(Joong-Ho Shin) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

During operation, cam-follower contacts experience a complex combination of cyclically-varying speed, load and geometry. The wear or surface fatigue can be reduced by maximizing the elastohydrodynamic film thickness. In this paper, an attempt has been made to estimate the optimal specific film thickness of cam-follower system quantitatively. A general TES polynomial function with real values of exponents is developed and genetic algorithm (GA) is used as optimization techniques for maximizing the minimum specific film thickness. The optimization programs enumerate values of the exponents for synthesis of cam displacement curves. The results show that the minimum film thickness can be increased considerably, e.g. approximately 7% in this paper.

캠 랙 피니언 시스템의 강도설계

권순만(Soon-man Kwon),차영빈(Young-Bin Cha) 한국생산제조학회 2021 한국생산제조학회지 Vol.30 No.3

The cam rack pinion (CRP) system takes the traditional rack and pinion concept and advances it by replacing the pinion teeth with bearing supported rollers that engage a trochoid rack tooth profile. The bearing supported rollers eliminate the sliding friction of the conventional rack and pinion with smooth rolling friction that yields a 99% efficient rotary to the linear motion conversion. In this study, the fatigue failure life of a CRP system was investigated. First, we investigated the difference in rack tooth profiles by changing the profile shift coefficient of CRP systems. Next, the Hertz contact stresses and tooth root bending stresses were analyzed by varying the profile shift coefficient to determine the tooth fatigue characteristics. It was found that the variation in the contact force with increasing the profile shift coefficient was insignificant, but the Hertz contact and tooth root bending stresses decreased significantly.

〈학술논문〉하이포 트로코이드 기어펌프의 접촉응력과 건마멸 특성에 관한 연구

권순만(Soon-Man Kwon),심무용(Muyong Sim),여뢰(Lei Lu),신중호(Joong-Ho Shin) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

The contact stress in a hypotrochoidal pump is addressed in this paper because it cannot be adjusted for wear. The first part of this paper presents a simple and exact rotor profile equations of the hypotrochoidal pump. In the second part of this paper, an explicit formular to avoid undercut in the outer-rotor of the hypotrochoidal pump is proposed by examining the minimum radius of curvature of the inner-rotor tooth profile on the convex section. Next, the contact stresses without hydrodynamic effect between the inner and outer-rotors are evaluated through the calculation of the Hertzian contact stress between the rotors' teeth. Based on the above results, we finally present the wear characteristics of p<SUB>H</SUB>V<SUB>s</SUB>. factor, which is proportional to the wear rate, between the rotors of the hypotrochoidal pump under quasi-static and dry contact conditions.

e-PGS 기반 요 감속기 피니언의 접촉 피로수명

권순만(Soon-man Kwon) 대한기계학회 2018 大韓機械學會論文集A Vol.42 No.6

풍력발전기용 요 시스템은 풍력발전기의 핵심부품이며, 그 구동은 복수 개의 요 감속기와 요 베어링 외주에 구비된 링 기어와의 치 물림에 의해 이루어진다. 하지만 MW급 대형 링 기어의 경우 설계로부터 제작에 이르기까지 글로벌 경쟁력이 열위인 것이 국내 관련 산업의 현실이며, 이에 본 연구에서는 이를 해소하기 위해 요 베어링 링 기어의 치형을 기존 인벌류트 치형에서 원형 핀 치형으로 대체한 e-PGS(external pinwheel gear set) 시스템을 그 대안으로 제시하였다. 이때 보다 높은 내피로 저항성을 얻기 위해 전위계수를 고려한 e-PGS 피니언 치형을 고려하였다. 이를 기반으로 접촉력 및 Hertz 접촉응력을 결정한 후 형상 설계제원 변화에 따른 요 감속기 피니언의 표면피로수명을 비교 평가하였다. 그 결과 전위계수를 증가시킴으로써 요 감속기 피니언의 피로수명이 상당히 연장될 수 있음을 알 수 있었고, 소정 값 이상의 전위계수로 설계되었을 때만이 목표수명 값을 얻을 수 있었다. The yawing system is a core component of a wind power generator and is driven by engaging several yaw reducers and a ring gear present on the outer periphery of the yaw bearing. However, the global competitiveness of domestic industries ranging from design to manufacture is poor with respect to MW-class large ring gears. To solve this problem, an external pinwheel gear set (e-PGS) system is introduced in this study as an alternative to the conventional yawing system. To obtain higher contact fatigue resistance in the pinion, we adopted a profile-shifted tooth profile. The contact forces were then determined and the Hertz contact stresses were investigated to estimate the surface fatigue life by varying the shape design parameters. Results of our proposed e-PGS system demonstrate that the fatigue design life of a yaw drive pinion can be extended significantly by increasing the profile shift coefficient. More specifically, we determined that an appropriate lifespan can be obtained only when this coefficient reaches or exceeds a certain level.

사회복지사의 감정노동이 직무만족에 미치는 영향에 대한 위험요인의 매개효과 연구

권순만(Kwon, Soon-Man),전순득(Jeun, Soon-Deuk),고재욱(Ko, Jea-Ug) 한국케어매니지먼트학회 2015 한국케어매니지먼트연구 Vol.16 No.-

본 연구자는 사회복지사의 감정노동이 직무만족에 미치는 영향과 위험관리를 매개로 양질의 사회복지 서비스제공을 위하여 사회복지사의 직무만족에 대하여 연구하고자 한다. 연구대상은 노인복지시설 178개 소 사회복지사를 대상으로 하였다. 연구결과 감정노동과 직무만족간의 부(-)의 상관관계가 존재하고 있었으며, 감정노동과 위험요인은 정(+)의 상관관계가 존재하고 있었다. 직무만족과 위험요인 간에는 부(-)의 감정노동 전체는 직무만족 전체에 부(-)의 영향을 미치는 것으로 나타났다(t=-2.521, p<0.05). 즉 감정노동이 높아지면 직무만족은 낮아진다는 것을 알 수가 있다. 상관관계를 보이는 것으로 감정노동이 직무만족에 미치는 영향에 대한 위험요인의 매개효과를 검증한 결과, 1단계에서 감정노동은 위험용인에 정(+)의 영향 을 미치는 것으로 나타났다. 2단계에서는 감정노동이 직무만족에 부(-)의 영향을 미치는 것으로 나타났다. 3단계에서는 매개변수인 위험요인이 직무만족에 영향을 미치고 있었으며, 독립변수인 감정노동은 직무만 족에 영향을 미치지 못하는 것으로 나타났다. 감정노동이 직무만족에 미치는 영향에 대해서 위험요인은 완전매개효과를 보이는 것으로 나타났다. 따라서 노인복지시설 사회복지사들의 직무만족 향상을 위하여 감정노동해소 방안을 적극적 검토하여야 할 것이다. The researchers would like to study the job satisfaction of social workers for the quality of social services provided by social workers mediated the impact of emotional labor on job satisfaction and risk management. The subjects were enrolled in 178 welfare facilities for the elderly social worker positions. (-) Portion between emotional labor and job satisfaction studies showed a correlation exists of emotional labor and the risk factors were correlated to the presence of the positive (+). Between job satisfaction and wealth appeared to affect risk factors of (t = -2.521, p <0.05). t is full of emotional labor on job satisfaction entire section(+). That emotional labor is higher, the lower job satisfaction can see that. Results showing the correlation between emotional labor EN Having examined the mediating effect of risk factors on the impact on job satisfaction and emotional labor in step 1 was found positive (+) effects on risk acceptance. In the second phase, part emotional labor job satisfaction - appeared to influence the (-). In the third step, the parameters of risk factors were affecting job satisfaction, emotional labor is the independent variable was found not to affect job satisfaction. That emotional labor is a risk factor for the impact on job satisfaction were seen to be fully mediated effects. Therefore, elderly welfare facilities will be actively reviewed relieve emotional labor measures to improve job satisfaction of social workers.

대학생의 스마트폰 이용이 일상생활 도움과 과다몰입 해소를 위한 거버넌스 개입방안에 관한 연구

권순만(Kwon, Soon-Man),김종상(Kim, Jong-Sang),성현주(Seong, Hyun-Ju) 한국케어매니지먼트학회 2016 한국케어매니지먼트연구 Vol.21 No.-

본 연구는 대학생의 스마트폰 이용이 일상생활에 어떠한 영향을 미치는지 보고 과다몰입 해소를 위한 거버넌스 개입 방안에 대하여 살펴보고자 하였다. 본 연구의 대상은 G시에 소재한 K대학교 대학생 554명이었고, 자료는 질문지법으로 수집하여 SPSS ver 18.0을 이용하여 통계적 자료처리를 실시하였다. 본 연구의 결과는 첫째, 대학생이 스마트폰을 오락휴식으로 이용할 경우 대인관계, 생활의 편리, 정보습득, 개인정보유출, 습관적, 불안초조에 영향을 미치는 것으로 나타났지만 사회적 위축에 대한 인식은 낮게 나타났다. 둘째, 대학생이 스마트폰을 태도행동결정으로 이용할 경우 편리성, 건강악화에 직접적인 영향을 미쳤다. 셋째, 대학생이 스마트폰을 이해인지와 태도행동결정으로 이용할 경우 소외감, 소비에 영향을 미치는 것으로 나타났지만 오락휴식으로 스마트폰을 이용할 경우 소비는 낮게 인식하고 있었다. 이러한 결과들은 대학생이 스마트폰을 통하여 일상생활에 도움이 미치는 요인을 알아보고 과다한 스마트폰 이용으로 몰입된 대학생뿐만 아니라 범국민을 위한 집단 심리치료 프로그램을 실시하고, 스마트폰 이용 관련 매뉴얼을 제작 및 배포하여 몰입 관련 요인에 따른 사례별 맞춤형 사례관리 서비스가 이루어질 수있도록 하며, 스마트폰 이용 관련 교육을 실시하여 잠재적 위험에 있는 몰입한 대상으로 예방적 서비스가 이루어질 수 있도록 해야 할 것이다. 본 연구를 통하여 대학생들의 일상생활에 많은 영향을 미치는 스마트폰 이용에 대한 질적 증대를 도모하고 무분별한 이용으로 야기되는 다양한 사회문제를 예방하기 위한 거버넌스 개입 방안을 수립하는 기초자료로서 의미가 있을 것이라 사료된다. This study identified the impacts of the use of smartphones of university students for their daily life and reviewed governance intervention to reduce their immersion in smartphones. The study targeted 554 students of K University in G city, collected the data from the questionnaire and conducted the statistical data processing using SPSS ver 18.0. As a result, first, the use of smartphones of university students for the purpose of recreation had impacts on interpersonal relationship, convenience in life, information acquisition, personal information leakage and habitual anxiety but the awareness of social withdrawal was low. Second, the use of smartphones for the purpose of attitude-behavior decision had direct impacts on convenience and deterioration in health. Third, while the use of smartphones for the purpose of understanding, recognition and attitude-behavior decision had impacts on a sense of alienation and consumption, the awareness of consumption was low when using smartphone for the purpose of recreation. The research finding should be used to conduct the collective psychological treatment programs for the public as well as university students who are excessively immersed in smartphones by reviewing the factors that can help the students’ daily life through smartphones; provide the customized case management services depending on the immersion factors by creating and distributing the manual on using smartphones; and come up with the preventive services for the immersed people who are in a potential danger by providing education on the use of smartphones. This study is considered significant as a basic data to improve the quality of smartphone use that highly affects the daily life of university students and establish the measures for governance intervention to prevent various social issues that may be caused by reckless use.

GOVERNMENT POLICY AND FINANCIAL PERFORMANCE OF REGULATED INDUSTRY ; LEGAL OWNERSHIP AND THE DYNAMIC EFFECT OF REGULATION

권순만 (Soon Man Kwon) 한국정책학회 1995 韓國政策學會報 Vol.4 No.1

In the regulation of inherently noncompetitive markets, the most difficult task of the government is to set the optimum payment schedule for goods and services produced by regulated firms, such that the price can both cover the cost of production and provide incentives for the firms to minimize expenditures. This paper examines the effect of government payment policy (as incentive regulation) on the investment behavior of regulated industry, through an example of the prospective payment system (PPS) implemented in the U.S. social insurance system. The results reveal that the new form of payment policy does not achieve its desired goal because over time, the regulated firms learn to avoid the direct enforcement of regulation by substituting nonregulated inputs for regulated ones. It is also shown that organizations with different legal ownerships (public, private not-for-profit, and private for-profit entities) respond to regulation in different ways. The importance of understanding the nature of incentives and their effect on regulated firms, evidenced in this study, should shed light on the design of public policy for other industries.