• 제목/요약/키워드: UT

검색결과 479건 처리시간 0.027초

원전 배관감육 평가를 위한 새로운 기법의 도입 및 타당성 (Introduction and Feasibility on a New Technology for the Pipe Wall Thinning Evaluation of Nuclear Power Plants)

  • 황경모;윤훈;박현철
    • Corrosion Science and Technology
    • /
    • 제13권2호
    • /
    • pp.62-69
    • /
    • 2014
  • A huge number of carbon steel piping components installed in the secondary system of nuclear power plants are exposed to aging mechanisms such as FAC (Flow-Accelerated Corrosion), Cavitation, Flashing, and LDIE (Liquid Droplet Impingement Erosion). Those aging mechanisms can lead to thinning of the piping components. To manage the wall thinning degradation, most of utilities in the world predict the wall thinning rate based on the computational program such as CHECWORKS, COMSY, and BRT-CICERO, evaluate the UT (Ultrasonic Test) data, and determine next inspection timing, repair or replacement, if needed. There are several evaluation methods, such as band, blanket, and strip methods, commonly used for determining the wear of piping components from single UT inspection data. It has been identified that those single UT evaluation methods not only do not consider the manufacturing features of pipes, but also may exclude the data of the most thinned point when determining the representative wear rate of piping components. This paper describes a newly developed single UT evaluation method, E-Cross method, for solving above problems and introduces application examples for several pipes and elbows. It was identified that the E-Cross method using the length and width of UT data excluded the most thinned points appropriate as the single UT evaluation method for thinned piping components.

고령자 친화형 유비쿼터스 주거환경 구축 연구 : 노인단독가구 유형별 유비쿼터스 홈 서비스 요구도를 중심으로 (The Development of Elderly-Friendly Ubiquitous Housing Environment : Focused on the Needs for Ubiquitous Home Services by Elderly Households without Children)

  • 권오정
    • 가정과삶의질연구
    • /
    • 제29권6호
    • /
    • pp.105-121
    • /
    • 2011
  • The purpose of this study was to propose ubiquitous housing environment based on older residents' needs for ubiquitous(UT) home services. For this purpose, at the previous study which was the first stage of this study, UT home services by each elderly household based on spouse, income level, and health status were identified and this study finally proposed UT home services by each elderly household type according to residents' level of needs for UT home services. One to one interview with a structured survey questionnaire and illustration was implemented and 204 older residents who were composed of one of six elderly household types were responded. Among 6 types of elderly households, type 2 and 6 were the groups which had higher needs for various kinds of UT home services. Economic status and their health status were the key factors to determine their needs for UT home services. Type 4 and 7 were the groups to express their lower needs for UT home services due to their lower income level and good health condition. Ultimately, two floor plans for type 4 and 5 elderly households were developed to show applicable UT home services in each room of the house.

Effect of Isometric Horizontal Abduction on Scapular and Shoulder Muscle Activity During Knee Push-up Plus With Different Shoulder Angles in Individuals With Scapular Winging

  • Jung-Hoon Choi;Heon-Seock Cynn;Seung-Min Baik;Seok-Hyun Kim
    • 한국전문물리치료학회지
    • /
    • 제30권2호
    • /
    • pp.160-168
    • /
    • 2023
  • Background: Individuals with scapular winging have a weak serratus anterior (SA) muscle, and to compensate, the pectoralis major (PM) and upper trapezius (UT) muscles excessively activate, which can cause upper extremity dysfunction. This study aimed to compare the effects of isometric horizontal abduction (IHA) on SA, PM, and UT muscle activity, as well as the SA/PM and SA/UT muscle activity ratios during knee push-up plus (KPP) at 90° and 120° of shoulder flexion. Objects: This study aimed to compare the effects of IHA on SA, PM, and UT muscle activity, as well as the SA/PM and SA/UT muscle activity ratios during KPP at 90° and 120° of shoulder flexion. Methods: This study, conducted at a university research laboratory, included 20 individuals with scapular winging. Participants performed KPP with and without IHA at 90° (KPP90) and 120° (KPP120) of shoulder flexion. SA, PM, and UT muscle activity were measured using surface electromyography. Results: PM activity in KPP90 with IHA was significantly lower than KPP90 and in KPP120 was significantly lower than KPP90. UT activity was significantly greater with IHA than without IHA and at 120° than 90° of shoulder flexion. SA/PM muscle activity ratio was significantly higher in KPP90 with IHA than without IHA and in KPP120 than in KPP90. SA/UT muscle activity ratio was significantly lower with IHA than without IHA. Conclusion: KPP90 with IHA and KPP120 are effective exercises to reduce PM activity and increase SA/PM muscle activity ratio. However, applying IHA in KPP90 also reduces SA/UT muscle activity ratio, implying that it would be preferable to apply KPP120 in individuals overusing their UT muscles.

Two-Dimensional Numerical Modeling and Simulation of Ultrasonic Testing

  • Yim, Hyun-June;Baek, Eun-Sol
    • 비파괴검사학회지
    • /
    • 제22권6호
    • /
    • pp.649-658
    • /
    • 2002
  • As an attempt to further improve the reliability and effectiveness of ultrasonic testing (UT), a two-dimensional numerical simulator of UT was developed. The simulator models the wave medium (or test object) using the mass-spring lattice model (MSLM) that consists of mass-points and springs. Some previous simulation results, obtained by using MSLM, are briefly reviewed in this paper, for propagation, reflection, and scattering of ultrasonic waves. Next, the models of transmitting and receiving piezoelectric transducers are introduced with some numerical results, which is a main focus of this paper. The UT simulator, established by combining the transducer models with the MSLM, was used to simulate many UT setups. In this paper, two simple setups are considered as examples, and their simulated A-scan signals are discussed. The potential of the MSLM, transducer models, and the UT simulator developed in this study to be used in the actual UT is confirmed.

SEASONAL AND UNIVERSAL TIME VARIATIONS OF THE AU, AL AND DST INDICES

  • AHN BYUNG-HO;MOON GA-HEE
    • 천문학회지
    • /
    • 제36권spc1호
    • /
    • pp.93-99
    • /
    • 2003
  • Various attempts have been made to explain the: pronounced seasonal and universal time (UT) variations of geomagnetic indices. As one of such attempts, we analyze the hourly-averaged auroral electroject indices obtained during the past 20 years. The AU and AL indices maximize during summer and equinoctial months, respectively. By normalizing the contribution of the solar conductivity enhancement to the AU index, or to the eastward electrojet, it is found that the AU also follows the same semiannual variation pattern of the AL index, suggesting that the electric field is the main modulator of the semiannual magnetic variation. The fact that the variation pattern of the yearly-mean AU index follows the mirror image of the AL index provides another indication that the electric field is the main modulator of magnetic disturbance. The pronounced UT variations of the auroral electrojet indices are also noted. To determine the magnetic activity dependence, the probability of recording a given activity level of AU and AL during each UT is examined. The UT variation of the AL index, thus obtained, shows a maximum at around 1200-1800 UT and a minimum around 0000-0800 UT particularly during winter. It is closely associated with the rotation of the geomagnetic pole around the rotational axis, which results in the change of the solar-originated ionospheric conductivity distribution over the polar region. On the other hand the UT variation is prominent during disturbed periods, indicating that the latitudinal mismatch between the AE stations and the auroral electrojet belt is responsible for it. Although not as prominent as the AL index, the probability distribution of the AU also shows two UT peaks. We confirm that the Dst index shows more prominent seasonal variation than the AE indices. However, the UT variation of the Dst index is only noticeable during the main phase of a magnetic storm. It is a combined result of the uneven distribution of the Dst stations and frequent developments of the partial ring current and substorm wedge current preferentially during the main phase.

둥근어깨를 가진 성인에게 위 등세모근 활성도 감소를 위한 중재가 둥근어깨자세, 위 등세모근 근활성도와 목기능장애지수에 미치는 영향 (Effect of Upper Trapezius Inhibition on Round Shoulder Posture, Upper Trapezius Muscle Activity and Neck Disability Index for Adults with Round Shoulders)

  • 최종욱;정용식;권오국
    • 대한정형도수물리치료학회지
    • /
    • 제26권1호
    • /
    • pp.9-18
    • /
    • 2020
  • Background: The aim of this study is for the effects of upper trapezius (UT) inhibition on round shoulder posture (RSP) index, pectoralis minor index (PMI), UT activity and neck disability index (NDI) in adults with RSP. Methods: 30 male and female participants with RSP were included in this study. The participants were divided into two groups: experimental group (EG) and the control group (CG). the EG received UT inhibition 3 days a week for 5 weeks those in the CG did not receive UT inhibition. Results: RSP index, PMI, UT activity and NDI were measured again, There was a significant difference within the EG at pre- result and post-results. Conclusion: These results suggest that UT inhibition with an RSP program was effective in decreasing the RSP index, UT activity, and NDI in adults with RSP.

절수시 Mongolian Gerbil 콩팥에서 TonEBP와 Urea transporter의 발현 변화 (Renal Expression of TonEBP and Urea Transporter in the Water-deprived Mongolian Gerbil(Meriones unguiculatus))

  • 박용덕;김성중;정주영
    • Applied Microscopy
    • /
    • 제37권4호
    • /
    • pp.271-280
    • /
    • 2007
  • Tonicity responsive enhancer binding protein(TonEBP)는 콩팥에서 osmolyte의 세포내 축적을 촉매해 주는 전사조절인자로 높은 삼투농도에서 세포를 보호하는데 중요한 역할을 수행한다. 고장성환경은 TonEBP의 양적 증가와 핵 내 분포의 증가를 통해 TonEBP의 활성을 자극한다. 또한 TonEBP는 콩팥 수질내 요소축적에 중요한 역할을 하는 UT-A의 전사를 조절하는 것으로도 알려져 있다. 따라서 본 연구에서는 콩팥수질내 TonEBP와 UT-A의 기능과 상관관계를 밝히는 연구의 일환으로 다른 동물보다 급수가 제한된 환경에서 더 오래 살아남을 수 있는 수분대사능력을 가지고 있는 Mongolian gerbil을 이용하여, 절수로 인한 고장성환경의 유발에서 TonEBP와 UT-A에 대한 발현 변화를 관찰하고자 하였다. 절수에 따른 TonEBP와 UT-A의 발현 양상을 연구하기 위해, 먼저 Mongoian gerbil 각 5마리씩 3그룹으로 나누어 절수 실험을 실시하였고, 면역조직화학법을 실시하여 다음과 같은 결과를 얻었다. 정상대조군에서 TonEBP의 면역반응성은 속수질 세포들의 핵 내에 주로 분포하였으며, 절수 7일군에서 면역조직화학검사 결과, 속수질집합관에서의 염색성은 대조군에 비해 증가하였고, 특히 바깥수질 부위에 속수질에서 요세관의 가는 부분에서의 증가가 두드러졌다. 절수 14일군에서 염색성이 대조군보다 오히려 감소하였으며, 콩팥의 조직학적 손상이 관찰되었다. UT-A의 경우 바깥수질 속줄무늬층의 짧은-헨레고리가는내림부분과 정상군에서는 미약한 양성반응을 나타낸 속수질 초기부분의 긴-헨레고리가는내림부분에서 강한 발현 양상을 나타내었고, 속수질의 초기에서 중간부위의 속수질집합관도 강한 발현 양상을 확인할 수 있었다. 그러나 속수질 말단부위의 속수질집합관은 콩팥유두 끝으로 갈수록 발현량이 감소하는 것을 확인할 수 있었다. 이상의 결과는 Mongolian gerbil을 이용한 절수모델에서 증가된 콩팥수질의 Tonicity에 의해 TonEBP의 발현이 증가하고 이에 따라 UT-A의 발현도 동반하여 증가하는 것을 확인하였고, 또한 이렇게 증가된 TonEBP는 UT의 전사를 조절하여 UT를 증가시켜 오줌농축기전을 향상시키는 것으로 생각된다. 이는 속수질 세포의 스트레스에 대한 세포방어기전으로 생각된다. 그러나 절수가 계속되면 이런 적응반응에 한계를 지나쳐 오히려 TonEBP와 UT-A의 발현이 감소함을 확인 할 수 있었다.

Comparison of the Effects of Closed Kinetic Chain Exercise and Open Kinetic Chain Exercise According to the Shoulder Flexion Angle on Muscle Activation of Serratus Anterior and Upper Trapezius Muscles During Scapular Protraction

  • Park, Ju-jung;Chon, Seung-chul
    • 한국전문물리치료학회지
    • /
    • 제24권4호
    • /
    • pp.11-19
    • /
    • 2017
  • Background: Methods for exercising serratus anterior (SA) and upper trapezius (UT) muscles are important for the recovery of patients with various shoulder disorders, yet the efficacy of closed or open kinetic chain exercises have not yet been evaluated. Objects: The purpose of this study was to compare the activation of the SA and UT muscles during scapular protraction considering both closed and open kinetic chain exercises. Methods: Thirty subjects were randomly divided into experimental groups (closed kinetic chain exercise) and control groups (open kinetic chain exercise) in which scapular protraction was performed at $90^{\circ}$ or $125^{\circ}$ shoulder flexion. Electromyographic activity data were collected from the SA and UT muscles per position and exercise method. Results: Separate mixed 2-way analysis of variance showed significant differences in the activation of the SA (F1,28=6.447, p=.017) and the UT (F1,28=35.450, p=.001) muscles between the groups at $90^{\circ}$ and $125^{\circ}$ shoulder flexion. Also, the SA/UT ratio measures at $90^{\circ}$ and $125^{\circ}$ shoulder flexion significantly differed between the groups (F1,28=15.457, p=.001). That is, the closed chain exercise was more effective than open chain exercise for strengthening the SA muscle and controlling the UT muscle, $125^{\circ}$ of shoulder joint was more effective than $90^{\circ}$. Conclusion: The findings suggest that scapular protraction with shoulder $125^{\circ}$ flexion at the closed kinetic chain exercise may be more effective in increasing SA muscle activation and decreasing UT muscle activation as well as increasing the SA/UT ratio than open kinetic chain exercise.

원자로냉각재계통 3" 분기관 용접부 위상배열초음파탐상검사(PAUT)기법 개발 (Development of the Phased Array Ultrasonic Test Technique for the Weld Inspection of Reactor Coolant System 3" Branch Connection Lines in Nuclear Power Plants)

  • 이승표;문용식;정남두;조용배;김창수
    • 한국압력기기공학회 논문집
    • /
    • 제4권2호
    • /
    • pp.40-45
    • /
    • 2008
  • There exist many types of pipe and component fatigue through vibrations, thermal fatigues or shifting. In some cases of thermal stratification/thermal fatigue, pipes & components are receiving thermal stress by means of material expansion and shrinkage by continuous thermal repetitive variation. Small cracks initially occur on the inside surface by thermal stress. These cracks grow in depth the pipe wall and finally come to a rupture. Pipe parts of susceptibility to thermal stratification and thermal fatigue are now being examined by conventional UT(ultrasonic test) as volumetric examination. It is difficult to fully satisfy the code & standards requirements because 3" weldolet weldments of RCS 16" pipe to 3" branch connection lines have complex structural shape. To solve the problems of conventional UT examination, we made a realistic mock-up and UT calibration block. We performed a simulation of phased array UT utilizing CIVA as NDE(Non-Destructive Examination) simulation software. Also we designed phased array UT transducer and wedge, optimal frequency by using simulation data. We performed phased array UT experiment through mock-up including artificial flaws(notch). The phased array UT technique is finally developed to improve the reliability of ultrasonic test at RCS 16" pipe to 3" branch connection weld.

  • PDF

Immediate Effects of Pulsed Magnetic Field in Subjects with Upper Trapezius Trigger Point

  • Kang, Sun-Young;Park, Joo-Hee;Song, Ja-Eik;Jeon, Hye-Seon;Lee, Hyun Sook
    • The Journal of Korean Physical Therapy
    • /
    • 제26권6호
    • /
    • pp.379-385
    • /
    • 2014
  • Purpose: This study was to determine the immediate effects of pulsed magnetic field (PMF) in subjects with upper trapezius (UT) trigger point (TrP). Methods: Fifteen subjects with UT TrP were recruited for the study's PMF group (pain threshold=$2.29kg/cm^2$), and 15 age-, weight-, and gender-matched subjects with UT TrP were recruited for control group (pain threshold=$2.25kg/cm^2$). Pressure algometer was used to measure pressure pain threshold on UT TrP and, cervical range of motion (ROM) inclinometer was used to measure cervical ROM. Surface electromyography was used to record UT, lower trapezius, and serratus anterior muscle activity and relative ratio during scapular plane abduction between pre- and post-treatment. Results: The PMF effectively improved pain threshold and concurrently increased ROM (rotation to the painful side, lateral flexion to the nonpainful side). In addition, the PMF may effectively deactivate UT activity during abduction and the muscle activity ratio between UT and serratus anterior. Conclusion: These findings provided empirical evidence that PMF can be an effective treatment method to reduce pain threshold, to increase cervical ROM, and deactivate UT activity in individuals with TrP.