• 제목/요약/키워드: effort

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Anti-slip 제어 알고리즘을 이용한 접착력 추정에 관한 연구 (A Study of Adhesive Effect Estimation using Anti-slip Control Algorithm)

  • 김길동;안태기;이우동;이호용;박서영
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.626-631
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    • 2004
  • In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the weight of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control algorithm which uses the maximum adhesive effort by instantaneous estimation of adhesion force using load torque disturbance observer. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.

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철도차량의 Anti-Slip 제어 및 속도센서리스 벡터제어 (Anti-Slip Control and Speed Sensor-less Vector Control of the Railway Vehicle)

  • 조정민;김길동
    • 한국철도학회논문집
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    • 제8권3호
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    • pp.216-221
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    • 2005
  • In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the wright of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control based on disturbance observer and sensor-less vector control. The numerical simulation and experimental results point out that the proposed re-adhesion control system has the desired driving wheel torque response for the tested bogie system of electric coach. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.

서비스 제공 시점에서 고객에게 지각된 판매원 노력의 선행변수와 결과변수

  • 김재영;이진용;한동철
    • 한국유통학회지:유통연구
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    • 제4권1호
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    • pp.1-16
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    • 1999
  • Although many studies have emphasized the importance of a saleperson's effort in the area of service marketing, no one has studied the variables which may influence, or may be influenced by salesperson's effort by customers. This study investigates the effects of percieved salesperson's effort on some performance variables and the effects of some selected variables on perceived salesperson's effort. Two sets of data were collected - one on the service of beauty hair shops and the other on that in fast food restaurants. The results indicate that empathy of employees is positively related to perceived effort, and perceived effort has the positive effects on satisfaction, trust, and long term relationship. However, the relationships between store image and perceived effort, and that between trust and long term relationship are only partly supported and the effects of perceived effort on long term relationship are not supported in our empirical tests.

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소프트웨어 개발노력 치적 분배에 관한 연구 (A Study of Optimal Effort Allocation over Software Development Phase)

  • 이상운;김용수;한판암
    • 정보처리학회논문지D
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    • 제9D권5호
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    • pp.865-876
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    • 2002
  • 성공적인 프로젝트 계획은 활용 가능한 일정과 더불어 프로젝트를 완수하는데 요구되는 노력을 얼마나 정확히 추정하느냐에 달려있다. 현존하는 소프트웨어 노력 추정 모델들은 샹명주기 전반에 걸쳐 투입되는 총 개발노력과 단위시간당 소요되는 노력 함수만을 제공한다. 또한, Putnam은 세부단계별로 일정한 개발노력 투입 비율을 제시하였다. 그러나 소프트웨어의 규모, 복잡도와 운영환경의 영향으로 인해 프로젝트 별로 투입되는 총 개발노력의 규모에 차이가 발생한다. 그 결과, 개발 세부단계별로 투입되는 노력의 규모도 프로젝트마다 차이가 발생한다. 본 논문은 소프트웨어 규모와 개발형태에 따라 계획, 명세, 구축, 시험과 이행단계에 투입될 노력을 추정하는 모델들을 제시하였다. 이 모델들은 155종의 다른 소프트웨어 프로젝트들로부터 유도되었다. 제안된 모델들은 프로젝트의 일정과 노력 분배 관리에 실질적인 지침을 제공할 것이다.

패션점포 판매원의 노력 차원과 중요도 -중.상층 노년여성고객과 판매원 관점을 중심으로- (Dimensions of Fashion Store Salesperson's Effort and Importance of Effort Dimension)

  • 신혜봉;임숙자
    • 복식문화연구
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    • 제11권1호
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    • pp.103-117
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    • 2003
  • The aim of this study was to identify dimensions of salesperson´s effort according to older female(55+) customer's and fashion store salesperson's perspective and to examine what kind of effort dimensions are assessed to be more important than others. As a method, both literature review and empirical research were made. This study was performed in three stage from December in 2001 to May in 2002. For exploratory step. In-depth interview and observation study were done for gathering responses related to salesperson´s effort. in pilot study, 83 older female customers were surveyed and the data was analyzed in order to develop questionnaire. In the main research. 202 older female customers and 103 fashion store salespersons were surveyed in order to identify the dimensions of salesperson's effort. Statistical analyses were performed with SAS program using factor analysis. cronbach´a mean, t-test. paired t-test and multiple regression analysis. The results of this study were as follows. First, 5 factors was selected for the dimensions of salesperson´s effort in customer´s perception; friendliness, attentiveness. product competence. effective access and special treatment. Second, 5 factors was selected for the dimensions of salesperson's effort in salesperson´s performance; friendliness/ attentiveness. product competence. effective access. communication, and purchase exaction. Third. dimensions of salesperson's effort were different according to customer and salesperson's characteristics. Last, there were significant differences in the salesperson's efforts between customers´perception and salespersons´Performance.

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축소형 철도차량장치의 점착력 추정에 의한 Anti-Slip 제어 (Anti-Slip Control By Adhesion Effort Estimation Of Minimized Railway Vehicle)

  • 전기영;이승환;강승욱;오봉환;이훈구;김용주;한경희
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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    • pp.536-539
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    • 2003
  • In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the weight of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control algorithm which uses the maximum adhesive effort by instantaneous estimation of adhesion force using load torque disturbance observer. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.

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부하토크외란관측기를 이용한 1C-4M 축소형 철도차량장치의 점착력 추정에 의한 Anti-Slip 제어 (Anti-Slip Control by Adhesion Effort Estimation of 1C-4 Minimized Railway Vehicle using Load Torque Disturbance Observer)

  • 전기영;조정민;이승환;오봉환;이훈구;김용주;한경희
    • 전력전자학회논문지
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    • 제8권4호
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    • pp.366-374
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    • 2003
  • 본 논문에서는 최대 견인력 제어를 위해서 부하 토크 외란 관측기를 이용하여 점착력 계수를 추정하고 추정한 점착력 계수의 미분치를 PI 토크 제어하는 Anti-slip 제어를 제안한다. 부하 토크 외란 관측기는 회전자의 위치 정보와 토크 전류의 정보를 이용하여 부하 외란 토크를 추정하고, 부하 외란 토크에 철도차량 상수를 미용하여 점착력 계수를 추정한다. 또한 부하토크외란 관측기는 구조가 간단하며, 시스템의 외란 및 각종 제어이득. 시스템의 상수 변화에 대해서도 견실한 견인력 제어 특성을 가지고 있다. 이와 같은 제어 알고리즘을 구현하기 위하여 IC4M(1-Controller 4-Motor) 축소형 철도차량시스템을 이용하여 제안된 알고리즘을 시뮬레이션과 실험을 통하여 확인하였다. 또한 실제 철도차량시스템의 경우 선로 표면의 상태 변화 및 차량속도의 가감에 따른 공전속도에 대한 점착력의 관계를 축소형 철도차량시스템으로 구현하여, 실제 철도차랑시스템의 경우와 비교 분석하여 최대 견인력제어가 되도록 하였다.

소프트웨어 개발 세부단계 노력 추정 모델 (A Model for Software Effort Estimation in the Development Subcycles)

  • 박석규;박영목;박재흥
    • 한국컴퓨터산업학회논문지
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    • 제2권6호
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    • pp.859-866
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    • 2001
  • 성공적인 프로젝트 계획은 활용 가능한 일정과 더불어 프로젝트를 완수하는데 요구되는 노력을 얼마나 정확히 추정하느냐에 달려있다. 새로운 또는 보다 나은 모델 개발에 많은 연구가 이루어졌지만 현존하는 소프트웨어 노력 추정 모델들은 개발 전순기에 대해 투입되는 총 개발노력과 단위시간당 소요되는 인력인 노력 함수만을 제공한다. 또한, Putnam은 세부단계별로 일정한 개발노력 투입 비율을 제시하였다. 그러나 소프트웨어의 규모, 복잡도와 운영환경의 영향으로 인해 프로젝트 별로 투입되는 총 개발노력의 규모에 차이가 발생하며, 그 결과, 개발 세부단계별로 투입되는 노력의 규모도 프로젝트마다 차이가 발생한다. 본 논문은 총 개발노력 변동에 따른 소프트웨어의 명세화, 구축과 시험단계에 투입될 개발노력을 추정하는 선형과 다항식 모델을 제시하였다. 이 모델들은 128개의 다른 소프트웨어 프로젝트들로부터 유도되었다. 제안된 모델은 프로젝트의 일정과 노력 할당 관리에 실질적인 지침을 제공할 것이다.

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입원 환아 어머니의 스트레스와 대처노력에 관한 연구 (A Study on the Stress and Coping Effort of Hospitalized Children's Mother)

  • 문영숙
    • 부모자녀건강학회지
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    • 제10권2호
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    • pp.147-157
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    • 2007
  • Purpose: Assessment of stress and coping effort of hospitalized children's mother are very important factor to support and recover the children. The purpose of this study was to identify the stress and coping effort in mothers whose children are hospitalized. And analyzes the correlation between mother's stress and coping effort on the hospitalized children. Method: This study surveyed 70 mothers whose children are hospitalized. The data was collected for this study at one university hospital in Daejeon from June 1,2007 to July 10, 2007. The instruments used in this study were the mother's stress scale which was developed by Ok-Nam, You(1998), modified by Ho-Jin, Mun(2001), and the mother's coping effort were measured with the Coping Health Inventory for Parents(CHIP) developed by McCubbin and Patterson(1981). The data was analyzed by using SPSS program and include ANOVA, and Pearson's Correlation. Result: The mother's stress was average 2.42 out of a possible 4 points. Type of coping effort was in order of type III(cope with it by understanding medical circumstances)(M=2.73), type I(Cope with it through positive definition)(M=2.43), type II (cope with it by maintaining psychological stability)(M=2.28). Total coping effort according to general character of mothers whose children are hospitalized showed a significant difference in occupation(P<.05). Correlations between mother's stress and total coping effort was r=-.361(P<.05). Conclusion: This study based on nursing of stress and coping effort of hospitalized children's mothers. Pediatric nurses need to establish a stronger communication board and a relationship between medical staff and children's parents so that have supportive information. And to establish a support program that strengthens the coping effort of hospitalized children's mothers.

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자동차 수동 변속기 클러치 시스템의 답력 이력 특성 예측 모델 (Automotive Manual Transmission Clutch System Modeling for Foot Effort Hysteresis Characteristics Prediction)

  • 이병수
    • 한국자동차공학회논문집
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    • 제16권5호
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    • pp.164-170
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    • 2008
  • A typical clutch system for automotive manual transmissions transfers hydraulic pressure generated by driver's pedal manipulation to the clutch diaphragm spring. The foot effort history during the period of push is different than the period of the clutch pedal's return. The effort or load difference is called clutch foot effort hysteresis. It is known that the hysteresis is caused by friction. The frictional force and moment are produced between various component contact points such as between the rubber seal and the inner wall inside the hydraulic cylinder and between the diaphragm spring and the pressure plate, etc. Understanding the clutch pedal foot effort hysteresis is essential for a clutch release system design and analysis. The dynamic model for a clutch release system is developed for the foot effort hysteresis prediction and a simulation analysis is performed to propose a tool for analysing a clutch system.