• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.6 no.2
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• pp.9-15
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• 2010

US NRC issued rulemaking of 10CFR50.55a to perform the Perservice and Inservice inspection for Reactor Vessel Head Penetration Nozzle of US Nuclaer plant. The rulemaking was required the EPRI Demonstration to verify the NDE technique performing special Ultrasonic examination. In order to meet this requirement, the UT and ECT procedures was demonstrated and the NDE personnel were qualified by EPRI. In this paper, the NDE technique and analysis method are described the Preservice inspection for the Palo Verde #1/2/3 Replacement Reactor Vessel Head Penetration Nozzle using the qualified procedures and personnel.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.300-300
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• 2007

최근 전기전자기기 및 광학기기 등의 소형화 및 고기능에 맞추어 구동 장치의 소형화가 필수적으로 요구됨에 따라, 보다 간단한 구조의 다양한 소형 압전 선형 모터에 대한 개발이 활발히 진행되고 있다. 본 연구에서는 굴곡 진동 모드를 갖는 평판형의 압전체와 탄성체로 구성된 압전 트랜스듀서와 두 개의 압전 트랜스듀서를 연결하여 타원 운동을 구현하기 위해, 굴곡 변형이 발생하는 한 쌍의 압전 트랜스듀서에 $90^{\circ}$ 위상차를 갖는 정현파를 각각 인가하여, 한 쌍의 압전 트랜스듀서를 연결하는 돌출부에서 타원궤적을 형성하는 소형 압전 액츄에이터를 설계하였다. 유한요소해석 프로그램인 ATILA를 이용하여 결합부의 타원 궤적의 형성하기 위한 압전 트랜스듀서의 최적 동작 주파수로 운동 모드를 결정하고자 한다.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.83-88
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• 2000

This study was conducted to determine the effect of repeated ultrasound-guided transvaginal retrieval of oocytes recovery, estrous cycle and ovarian adhesion in Korean native, Hanwoo heifers. Heifers were at unknown stages of the estrous cycle at the start of experiments in which all follicles $\geq$6mm in diameter were ablated. The results obtained in this study were as follows; Follicle developing number and oocytes collected number were no effected to repeated OPU to nine session, 4 e.a range oocytes collected to repeated OPU session. Oocytes were observated follicles were 8.7$\pm$4.2 e.a, collected oocytes were 4.1$\pm$3.4 e.a to two times collected per week and observated follicles was 10.2$\pm$6.1 e.a, collected oocytes were 4.3$\pm$2.9 e.a to one times collected per week, but no difference significantly(P＜0.05). Ovaries adhesive percentage to repeated OPU was eight ovaries adhisived(20%) of forty ovaries, three ovaries(7.5%) to 1~3 times oocytes collected, four ovaries(l0%) to 4~6 times, one ovaries(2.5%) to 7~9 times oocytes collected session. To repeated OPU effection, ovaries adhisive heifers were long estrous cycle(＞25 day) to 7 heads(87.5%) of 8 head, non-adhesive ovaries heifers were 5 heads(41.7%) were long estrous cycle to repeated OPU 12 heads. Although, now unknown about the dynamics of follicles wave and about functional changes to repeated OPU ovaries, more question about ovaries adhesive cause remain.

• Nuclear industry
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• v.23 no.3 s.241
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• pp.42-48
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• 2003

가압 경수로는 원통형의 원자로 용기 안에서 핵물질을 반응시켜 고온$\cdot$고압의 물을 생성하는데 이 원자로 용기는 환형 주조물들을 서로 용접하여 만들어진다. 이 원자로 용기의 건전성을 확인하기 위해서는 용접부위에 결함이 발생되었는지를 주기적으로 정확하게 검사해야 한다. 한국원자력연구소는 원자력발전소의 핵심 기기인 원자로 용기의 용접부 결함을 수중에서 자동으로 검사, 탐지할 수 있는 $\ulcorner$원자로 자동 탐상 시스템$\lrcorner$을 개발하여, 울진 원전 6호기용 원자로 용기에서 실증 실험을 수행하였다. 이 원자로 자동 탐상 시스템은 물방개처럼 생긴 수중 탐상 로봇이 그 핵심으로서 이 로봇은 원자로 용기의 내벽을 타고 다니면서 수중 초음파 검사를 수행할 수 있는 획기적인 시스템이다. 본고에서는 개발된 원자로 자동 탐상 시스템을 소개하고자 한다.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.77-82
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• 2000

This study was conducted to establish the methods of ultrasound-guided transvaginal retrieval of oocytes (ovum pick-up) in Korean native, Hanwoo Heifers. To obtain the basic data about Hanwoo, the size of ovaries in luteal and follicular phases were measured and the number of follicles in ovaries during the estrus cycle was counted by using ultrasound. And to determine the effective anesthetic to Hanwoo, various mixture of anesthetic compounds, Rompun(equation omitted), lidocaine, Monzal(equation omitted), and Domosedan(equation omitted), were treated. The size of Hanwoo ovaries were not significant differently between luteal and follicular phases. The number of medium and small follicles were peak on day 3 and 12 of the estrous cycle, and this result suggested that Hanwoo has 2 follicular growth waves per estrus cycle. The most effective anesthetic method was intramuscular injection of a.3m! Rompun(equation omitted), epidural injection of 5$m\ell$ lidocaine and sprayed cervix by 2$m\ell$ lidocaine.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.2
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• pp.117-121
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• 2008

Prolotherapy can be defined as the injection of growth factors or growth factor production stimulants to grow normal cells or tissue. Even though it has been a controversal procedure for decades, it is currently gaining in popularity among many physicians. The term prolotherapy was coined by Hacket in the 1950s to imply proliferation of normal tissue at ligamentous and tendinous entheses. The procedure has been described by other terms, such as sclerotherapy, regenerative injection therapy, and stimulated ligament repair. Incomplete healing from sprains or strains is common and can lead to chronic pain, joint instability and laxity, and is a risk factor for the development of osteoarthritis. Prolotherapy is commonly used for these musculoskeletal conditions which are refractory to usual care therapies. The proliferant solution and technique varies according to physicial training and preferance. Commonly reported proliferants include 10% to 25% dextrose, P2G and sodium morrhuate. High resolution ultrasound imaging of musculoskeletal tissue is increasing in popularity because of patient tolerability, low cost, ability to visualize tissue in real time motion and superior resolution of highly organized tissue such as a tendon. This procedure can be introduced by ultrasound imaging and tissue growth and repair after this procedure in a tendon or a ligament can be documented with ultrasound.

• The Journal of the Acoustical Society of Korea
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• v.41 no.5
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• pp.564-569
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• 2022

Blood-Brain Barrier (BBB) is the brain protecting system blocking the inflow of harmful substances into brain parenchyma from brain blood vessel. However, the BBB has a negative effect on the treatment of various brain diseases such as Alzheimer's dementia or brain tumors because it also prevents drug delivery into brain parenchyma. To overcome this problem, a brain drug delivery technique using Focused Ultrasound (FUS) which allows BBB to be temporarily opened by inducing the acoustic cavitation effect of microbubbles has been developed. Thus far, various studies using the FUS technique has been conducted to improve drug delivery efficiency, and therefore, this paper discusses recently developed drug delivery technologies using the FUS-induced BBB opening.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.507-512
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• 2011

Recently, various new devices have been introduced, which are capable of quickly measuring river hydrodynamic and morphologic features in the very broad riverine area. These devices are changing paradigm of understanding river characteristics in terms of data-driven aspect rather than the conventional numerical modeling approaches based on the limited field observations. This paper demonstrates the representative features and applications of the several recent riverine devices such as ADCP, LSPIV, MBES and ABL. In addition, the paper introduces an example of river information system that incorporates and relates such two- and three-dimensional hydrodynamic and morphologic data on top of geographic information system, where their spatio-temporal variations are also able to be tracked.

• Journal of the Korean Society of Radiology
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• v.12 no.2
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• pp.217-223
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• 2018

This study to search the diagnostic performance of shear wave elastography(SWE) in breast mass and to compare the biopsy result and stiffness obtained from shear wave elastography. Diagnostic breast ultrasonography and SWE were targeted for 157 patients who had breast ultrasonography was diagnosed mass from June 2017 to September 2017. Pathology results of 157 patients showed a benign 92 patients(Age, $44.54{\pm}11.84$) and a malignancy 65 patients(Age, $51.55{\pm}10.54$). Final evaluation, biopsy result, and quantitative SWE result were obtained and compared with each other according to Breast Imaging Reporting and Data System(BI-RADS) of diagnostic breast ultrasonography. Quantitative SWE value and pathologic result showed the highest diagnostic specificity of 83.70% in Emean and sensitivity of 89.23% in Emin. Quantitative SWE result and biopsy result is statistically significant.(p=0.000). The optimal cut-off value for malignant lesions was 66.3 kPa and 63.7 kPa, respectively, for the sensitivity, specificity, high maximum mean elasticity value(Emax) and mean elasticity value(Emean) and this showed the highest diagnostic area under the ROC curve(Az) value compared to other SWE measurement(p=0.000). The addition of SWE to conventional US in breast mass make a increase diagnostic specificity and reduce unnecessary biopsy. Therefore, it is expected that it will be helpful to analyze the breast mass using the above analysis and apparatus.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.40-45
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• 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.