• 제목/요약/키워드: one-way rotation

검색결과 126건 처리시간 0.027초

도시철도차량 주행풍을 이용한 터빈형 플라이휠 에너지 저장시스템 개발에 관한 연구 (Development of a Turbine Based Flywheel Energy Storage System Using Traveling Wind Power of an Urban Train)

  • 서용범;임재문;신광복
    • 한국생산제조학회지
    • /
    • 제23권5호
    • /
    • pp.443-449
    • /
    • 2014
  • This study aims to develop a Flywheel Energy Storage System (FESS) that uses wind power produced when an urban train is in motion, by utilizing a mounted turbine. This system was designed to generate and store electric power from wind power of a travelling urban train. The flywheel was designed to continue rotation using a one-way clutch bearing installed in the turbine shaft pulley, even in cases where the urban train decelerates or stops. This FESS can generate an additional 44% of electric power in comparison to a system not equipped with a flywheel. The generated power and operational features of the FESS were evaluated and verified through a wind tunnel test. The results show that the electric power stored in the FESS could supply auxiliary power for urban train components or service equipment, such as charging mobiles, Wi-Fi modules, and electric lights.

Vibration suppression of a double-beam system by a two-degree-of-freedom mass-spring system

  • Rezaiee-Pajand, Mohammad;Sani, Ahmad Aftabi;Hozhabrossadati, Seyed Mojtaba
    • Smart Structures and Systems
    • /
    • 제21권3호
    • /
    • pp.349-358
    • /
    • 2018
  • This paper investigates the free vibration analysis of double-beam system coupled by a two-degree-of-freedom mass-spring system. In order to generalize the model, the main beams are assumed to be elastically restrained against translation and rotation at one end and free at the other. Furthermore, the mass-spring system is elastically connected to the beams at adjustable positions by means of four translational and rotational springs. The governing differential equations of the beams and the mass-spring system are derived and analytically solved by using the Fourier transform method. Moreover, as a second way, a finite element solution is derived. The frequency parameters and mode shapes of some diverse cases are obtained using both methods. Comparison of obtained results by two methods shows the accuracy of both solutions. The influence of system parameters on the free vibration response of the studied mechanical system is examined.

간호사가 지각한 간호조직 문화유형 및 수간호사의 리더십 유형이 직무만족에 미치는 영향 (Effects of the Nursing Organizational Culture and Head Nurse's Leadership on the Job Satisfaction)

  • 한지영
    • 한국병원경영학회지
    • /
    • 제14권3호
    • /
    • pp.1-22
    • /
    • 2009
  • Purpose : The purpose of this study was to examine the effects of nursing organizational culture and head nurse's leadership on the job satisfaction. Methods : For the purpose, a structured questionnaire was conducted. The subjects were 232 nurses who were working in the 2 general hospitals. The data were collected from Sep. 1 to Sep. 20 of 2006. Data were analyzed using descriptive statistics, one-way ANOVA, t-test, Pearson Correlation Coefficient, and multiple regression. Results : The dominant organizational culture of nursing organization was rank-oriented culture. The mean score of head nurse's transformational leadership and transactional leadership was 3.20 and 2.79 respectively. The best group of job satisfaction was affiliative-oriented culture group(3.31). The score of job satisfaction of transformational leadership's group was higher than that of transactional leadership's group. Job satisfaction was positively correlated with affiliative-oriented culture, innovative-oriented culture, task-oriented culture, and transformational leadership. Concerning of the job satisfaction, affiliative-oriented culture, rotation time and age explained 25.7%. Conclusion : The organizational culture and head nurse's leadership was correlated with job satisfaction. Especially affiliative-oriented culture and task-oriented culture influenced the job satisfaction. Based on the results, further development should be continued to develop the effective head nurse's leadership and organizational culture to improve the job satisfaction of nurses.

  • PDF

Fuzzy Logic을 이용한 센서의 왜곡 현상의 지능형 추론 시스템 설계 (Design of Intelligent system with Fuzzy Logic for MR Sensor in destortion)

  • 김영구;박창규
    • 한국정보통신학회논문지
    • /
    • 제11권10호
    • /
    • pp.1986-1991
    • /
    • 2007
  • 본 논문에서 지구자기장을 측정하여 방위를 결정하는 자기 저항 소자의 경사각의 이상 현상에서 있어 예측할 수 없는 특성에 대해 불확실성에서의 추론을 통해 센서로서의 안정성을 확보하는데 그 목적이 있다. 따라서 퍼지 알고리즘을 적용하여 외부 환경 변화에 민감하게 변화하는 소자의 왜곡현상을 프로그래밍 적인 요소를 실험하여 센서의 왜율적인 요소에서 벗어남을 보인다. 나아가 소자의 고속, 고신뢰성을 갖는 응용에 사용할 수 있음을 보인다.

The Effects of Myofascial Trigger Point Release and Mobility Exercise on Pain and Functions in Patient with Rotator Cuff Tendinopathy

  • Shin, Beom-Cheol;Choi, Wonjae;Jung, Jihye;Lee, Seungwon
    • Physical Therapy Rehabilitation Science
    • /
    • 제11권2호
    • /
    • pp.269-278
    • /
    • 2022
  • Objective: The aim of this study was to evaluate the effects on pain and function of patients with rotator cuff tendinopathy when applying trigger point of infraspinatus and teres minor to myofascial trigger point release (MFR) plus mobility exercise and MFR. Design: A randomized controlled trial. Methods: The total participants were 30patients and were separated to MFR plus mobility exercise group(n=15) and MFR group (n=15) according to the randomized treatment method. The MFR was performed at two infraspinatus tampon points and one teres minor tampon point for twice a week for 4 weeks and the treatment time was 6 minutes 20 seconds in each position. The MFR group also carried out the myofascial trigger point release in the same way as the MFR plus mobility exercise group. Results: The MFR plus mobility exercise group significantly reduced objective and subjective pain (p<0.05). The range of motion of the shoulder joint flexion and external rotation, Quick-Disability of the Arm, shoulder and Hand, and Shoulder Pain and Disability Index were significantly improved in the group to which MFR plus mobility exercise was applied (p<0.05). Conclusions: These results confirmed that MRF plus mobility exercise is more effective in relieving shoulder pain and improving function in rotator cuff tendinopathy.

한국형 치과위생사 직업기대 수준 측정 도구 개발 (Development of a Korean version of the job expectations scale for dental hygienists)

  • 정미애;김형미;배정희
    • 한국치위생학회지
    • /
    • 제23권5호
    • /
    • pp.369-377
    • /
    • 2023
  • Objectives: The aim of this study was to develop and validate a Korean-adapted version of the job expectations scale for dental hygienists. Methods: To achieve this goal, a comprehensive methodology was employed, including frequency analysis, exploratory factor analysis (maximum likelihood, direct oblimin rotation), confirmatory factor analysis, Cronbach's α reliability, independent t-test, and one-way ANOVA (Duncan post-hoc test) were performed. Results: The Korean version of job expectations scale for dental hygienists comprised 21 items in the personal domain and 5 items in the social domain. The scale demonstrated high construct validity, convergent validity, discriminant validity, and reliability were found. While dental hygienists were found to have higher expectations in the their personal domain than the social domain, expectations in the social domain were higher among male hygienists, those with a bachelor's degree or higher, those in regular permanent employment, and those working in hospital-level or higher facilities. Conclusions: Job expectations is a more comprehensive construct than job roles or professional identity. We anticipate that the instrument will be widely used to analyze trends in job expectations in response to changes in societal values regarding to dental hygienists, the gap between realities and ideals within the dental hygiene profession, and policy considerations.

PSC 박스거더 교량의 상호작용에 의한 KTX 동력차의 윤하중 분포 해석 (A Dynamic Analysis of Wheel Forces distribution of KTX locomotive for Interaction of PSC box Girder Bridge)

  • 오순택;이동준;심영우;윤준관;김한수
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2011년도 춘계학술대회 논문집
    • /
    • pp.680-689
    • /
    • 2011
  • A dynamic analysis procedure is developed to provide a comprehensive estimation of the dynamic response spectrum for locomotive's wheels running over a Pre-Stressed Concrete (PSC) box girder bridge on the Korea high speed railway. The wheel force spectrum with the bridge behavior are analyzed as the dynamic procedure for various running speeds (50~450km/h). The high-speed railway locomotive (KTX) is used as 38-degree of freedom system. Three displacements(vertical, lateral, and longitudinal) and three rotational components (pitching, rolling, and yawing). For one car-body and two bogies as well as five movements except pitching rotation components for four wheel axes forces are considered in the 38-degree of freedom model. Three dimensional frame element is used to model of the PSC box girder bridges, simply supported span length of 40m. The irregulation of rail-way is derived using the exponential spectrum density function under assumption of twelve level tracks conditions based on the normal probability procedure. The dynamic responses of bridge passing through the railway locomotive with high-speed analyzed by Newmark-${\beta}$ method and Runge-Kutta method are compared and contrasted considering the developed models of bridge, track and locomotive comprehensively. The dynamic analyses of wheel forces by Runge-Kutta method which are able to analyze the forces with high frequency running on the bridge and ground rail-way are conducted. Additionally, wheel forces spectrum and three rotational components of vehicle body for three typical running speeds is also presented.

  • PDF

중년여성의 가시위근 봉합술전 어깨뼈 안정화운동이 통증과 ROM향상에 미치는 영향 (The Effects of Scapular Stabilization Exercise before Rotator Cuff Repair on Pain and ROM of Middle-aged Women)

  • 김태엽;유병국
    • 대한통합의학회지
    • /
    • 제2권1호
    • /
    • pp.63-76
    • /
    • 2014
  • Purpose : The purpose of this study was to ascertain the effects of scapular stabilization exercise before rotator cuff surgery on pain and range of motion of middle-aged women. Method : 20 subjects who agreed on this experiment and were diagnosed with rotator cuff rupture participated in this study. Experimental groups were treated while 40 minutes a day, 5 times per week, for 2 weeks before surgery. The effects of scapular stabilization exercise were evaluated on VAS and range of motion. Collected data were analyzed with SPSS for windows ver. 20.0 program. One-way repeated ANOVA was used to examine a significance of each variable by time. Two-way repeated ANOVA was applied to examine a significance of the experimental group against the control group. In all statistical tests, the significance level was set by ${\alpha}=.05$. Result : The results of this study are as follows: 1) In both control and experimental groups, VASs were decreased significantly according to intervention period. There was no significant difference between VASs of two groups. 2) In both control and experimental groups, ROMs of shoulder, flexion, abduction and external rotation were increased significantly according to intervention period. In these three flexibility measurement variables, there were significant differences between ROMs of two groups. Conclusion : In view of all the results in this study, scapular stabilization exercise on before rotator cuff surgery proved to be effective in improving their pain, range of motion after surgery. It will be sufficient data to perform with their own exercise program.

모래지반에서 반복수평하중을 받는 말뚝의 영구변형 (Permanent Deformations of Piles in Sand Under Cyclic Lateral Loads)

  • 백규호;박원우
    • 한국지반공학회논문집
    • /
    • 제26권11호
    • /
    • pp.63-73
    • /
    • 2010
  • 해상풍력발전기의 기초로 사용되는 단말뚝은 풍력과 파랑하중에 의해 큰 크기의 반복수평하중을 받는다. 본 연구에서는 모래지반에서 반복수평하중을 받는 항타말뚝의 거동 특성을 조사하기 위해서 가압토조와 길이가 다른 3개의 모형말뚝을 이용해서 모형말뚝재하시험을 수행하였다. 실험결과에 따르면 하중의 최초 재하는 그 이후에 가해지는 반복재하보다 말뚝의 수평변위를 크게 발생시키고, 반복하중의 재하횟수가 증가함에 따라 1회 재하로 인해 발생하는 말뚝의 수평변위량은 감소하는 것으로 나타났다. 하중의 한방향 반복재하는 말뚝의 영구수평변위를 재하방향으로 증가시킨 반면, 양방향 반복재하는 최초 재하방향과 반대방향으로 말뚝의 영구수평변위를 증가시켰다. 그리고 반복 하중으로 인한 말뚝의 영구수평변위는 지반의 상대밀도가 감소하거나 말뚝에 가해지는 반복하중의 크기가 커질수록 급격히 증가하였고, 지반의 토압계수나 말뚝의 근입길이 변화에는 크게 영향을 받지 않았다. 또한 모형실험의 결과에 근거해서 하중이 한방향으로 반복재하될 때 말뚝의 영구수평변위와 영구회전각을 예측할 수 있는 산정식을 제안하였다.

의복의 색과 신체노출이 정숙성인상에 미치는 영향 (Effect of Body Exposure and Color of Suit on the Impression of Modesty)

  • 고애란;강혜원
    • 한국의류학회지
    • /
    • 제16권3호
    • /
    • pp.181-195
    • /
    • 1992
  • The purposes of this study were to investigate 1) the effect of body exposure and color of a woman's suit on the perception of modesty, and 2) the effect of perceiver's sex and age on impression formed by the function of clothing variables. The instrument of this study consisted of a response scale and stimuli. Thirteen items of 7-point semantic differential scales were developed to measure the perceiver's impression on wearer's modesty. Stimuli were color pictures of a model wearing one of 8 types of suit constructed by a 2 $\times$ 2 $\times$ 2 factorial design. The manipulation of each level of the clothing variables were: color of the suit by black and red, leg exposure by varying skirt lengths to a Chanel-line and mini skirt, and neck exposure by shirt collar blouse and scarf. Two models, representing typical female college students living in Seoul, were selected to eliminate model effect. The sample include 384 subjects, consisting of 4 groups of male and female college students and middle aged men and women. Eight experimental groups were randomly assigned to one of eight stimuli based on between-subject design. One half of each group responded to model 1 and the other half to model 2 of same stimulus. Responses to the semantic differential scales were factor analyzed (pc model, Varimax rotation) to identify factors constructing impression of modesty. Two factors emerged regard­less of subgroups; Elegance and Extroversion factor. The first factor was found to be dominant, accounting for 60 percent of the total variance. The other accounted for just 11 percent. Multidimensional ANOVA (5-way, 3-way) was conducted to test the effect of the clothing variables against two factors identified from the factor analysis. Leg exposure was the most powerful variable affecting the impression of Elegance and Extroversion factor for all per. ceiver subgroups. Neck exposure had primary effect on the impression of Elegance, whereas it partially influenced that of Extroversion. Color of suit had only partial effect on the impression of Extroversion. Hypothesis I was partially supported from the findings above. The effect of perceiver's age and sex on impression by the function of clothing variables was tested by comparing the result between four subgroups. In forming an impression of the wearer's modesty, male college students were least affected by the manipulation of clothing variables, while middle aged males were affected most. In the female groups, there was no age difference and they fell between the male groups in the degree to which they were affected. Hypothesis II was supported only by age difference in two male groups, and by sex difference in two student groups.

  • PDF