• 한국도로학회논문집
• /
• 제12권3호
• /
• pp.1-8
• /
• 2010

본 연구는 콘크리트 슬래브 및 포장도로에 덧씌우기 포장으로 개발된 아크릴 폴리머 콘크리트의 물리 역학적 특성을 평가하기 위하여 수행되었다. 점도시험, 흐름시험, 압축강도시험, 휨 강도시험, 인장강도시험, 선 수축시험, 열팽창계수시험 및 온도변화에 대한 부착성 등 다양한 실내 시험을 실시하였다. 본 연구에서 개발된 아크릴 폴리머 콘크리트의 실내시험 결과 ACI에서 제시하는 모든 기준을 만족하는 것으로 평가되었다. 아크릴 폴리머 콘크리트의 공용성을 평가하기 위해 추가적으로 포장가속시험(APT)을 수행하였으나 등가 단축하중을 15,909,939회를 적용하는 동안 심각한 파손을 확인할 수 없었다. 마지막으로 현장 적용성을 평가하기 위하여 열화현상이 진행된 콘크리트 도로에 10mm의 폴리머 콘크리트 덧씌우기를 적용하였다. 현장 적용 후 미끄럼 저항성, 소음 및 평탄성을 측정한 결과 미끄럼 저항성 및 소음도는 상당히 개선되었으나 평탄성 측정치는 다소 증가하였다. 추후 현장에 적용된 아크릴 폴리머 콘크리트의 정기적인 조사를 통하여 장기 공용성 평가를 수행할 예정이다.

• 터널과지하공간
• /
• 제20권5호
• /
• pp.332-343
• /
• 2010

본 연구는 시공성, 효율성, 경제성, 안정성, 환경성 측면에서 기존 록 볼트보다 지보재 특성이 우수한 스파이럴 볼트의 적용 확대 활성화 방안으로 대체 지보재로서 스파이럴 볼트의 지보효과를 평가하는데 있다. 본 연구를 위하여 현재 가장 일반적으로 사용되고 있는 기존 록 볼트와 스파이럴 볼트에 대한 역학적 특성을 비교하였으며, 실내인발시험을 수행하여 지보재의 변위, 인발하중, 구속압 등 지보재의 성질을 살펴보았다. 또한 현장 원위치 인발시험을 실시한 결과를 실내인발시험과 비교하여 기존 록 볼트와 스파이럴 볼트의 지보특성 차이점을 평가하였다. 이상의 실내 및 현장시험에서 얻어진 결과를 FLAC3D를 이용한 수치해석 결과와 비교하여 두 지보재의 지보효과 차이를 분석하였다.

• Journal of Genetic Medicine
• /
• 제4권1호
• /
• pp.1-5
• /
• 2007

Unprecedented amount of genetic information being generated from the result of Human Genome Project (HGP) and advances in genetic research is already forcing changes in the paradigm of health and disease. The ultimate goal of genetic medicine is to use genetic information and technology to develop new ways of treatment or even prevention of the disease on an individual level for 'personalized medicine'. Genetics is play ing an increasingly important role in the diagnosis, monitoring and management of common multifactorial diseases in addition to rare single-gene disorders. While wide range of genetic testing have provided benefits to patients and family, uncertainties surrounding test interpretation, the current lack of available medical options for the diseases, and risks for discrimination and social stigmatization may remain to be resolved. However an increasing number of genetic tests are becoming commercially available, including direct to consumer genetic testing, yet public is often unaw are of their clinical and social implications. The personal nature of information generated by a genetic test, its power to affect major life decisions and family members, and its potential misuse raise important ethical considerations. Therefore appropriate genetic counseling is needed for patient to be informed with the benefits, limitations and risks of genetic tests, prior to informed consent for the tests. Physician also should be familiar with the legal and ethical issues involved in genetic testing to tell patients how w ell a particular genetic risk factor relates with likelihood of disease, and be able to provide appropriate genetic counseling. Genetic counseling become a mandatory requirement as global standard for many genetic testing such as prenatal diagnosis, presymtomatic DNA diagnostic tests and cancer susceptibility gene test for familial cancer syndrome. In oder to meet the challenge of genetic medicine of 21 century in korean health care system, professional education program and certification board for medical genetics specialist including non-MD genetic counselors should be addressed by medical society and regulatory policy of national health insurance reimbursement for genetic counseling to be in place to promote the implementation of clinical genetic service including genetic counseling for proper genetic testing.

• 한국전산구조공학회논문집
• /
• 제32권5호
• /
• pp.279-286
• /
• 2019

본 논문에서는 가스건 시험에서 원충격자의 충격 감가속도 예측에 관한 전산해석적 연구를 수행하였다. 무기체계 개발에 있어서, 가스건 시험을 통한 수만 G 이상에서의 내고충격성능에 대한 검증은 필요하다. 시험품이 받는 충격 감가속도는 버드조립체의 형상, 무게, 비행 속도 등 여러 변수에 의존하기 때문에 충격 감가속도를 생성시키는 적합한 시험조건을 찾는 것은 매우 중요하다. 하지만, 시험을 통해 기본적인 데이터를 구축하는 것은 경제적인 측면에서 비효율적이기 때문에 전산해석적 기법을 확보하여야 한다. 이에 본 연구에서는 130mm 가스건 시험을 바탕으로 획득한 데이터를 기반으로 하여 Explicit 코드를 사용하는 ANSYS AUTODYN을 활용하여 전산해석을 수행하였다. 전산해석을 통해, 시간에 따른 시험품의 동적거동현상 뿐만 아니라 전산해석결과를 시험결과와의 비교 및 분석을 함으로써 검증을 수행하였다.

• 한국해양공학회지
• /
• 제35권5호
• /
• pp.313-326
• /
• 2021

A submerged body with varied control inputs can execute large drift angles and large angles of attack, as well as basic control such as straight movement and turning. The objective of this study is to analyze the dynamic characteristics of a submerged body comprising six thrusters and six control planes, which is capable of a large drift angle and angle of attack motion. Virtual captive model tests via were analyzed via computational fluid dynamics (CFD) to determine the dynamic characteristics of the submerged body. A test matrix of virtual captive model tests specialized for large-angle motion was established. Based on this test matrix, virtual captive model tests were performed with a drift angle and angle of attack of approximately 30° and 90°, respectively. The characteristics of the hydrodynamic force acting on the horizontal and vertical surfaces of the submerged body were analyzed under the large-angle motion condition, and a model representing this hydrodynamic force was established. In addition, maneuvering simulation was performed to evaluate the standard maneuverability and dynamic characteristics of large-angle motion. Considering the shape characteristics of the submerged body, we attempt to verify the feasibility of the analysis results by analyzing the characteristics of the hydrodynamic force when the large-angle motion occurred.

• Journal of Acupuncture Research
• /
• 제36권2호
• /
• pp.100-106
• /
• 2019

Background: In Korean medicine, carpal tunnel syndrome is treated by stimulating the acupoints around the wrist. Although a deep understanding of anatomy and guidance is needed to stimulate these acupoints to avoid undesirable side-effects, currently there are no published guidelines for acupotomy treatment. The aim of this study is to evaluate the effectiveness and safety of fluoroscopy-guided acupotomy compared with conventional acupotomy treatment. Methods: This is a randomized, patient-assessor, patient blind, parallel clinical trial. A total of 30 patients will be enrolled at Wonkwang University Gwangju Hospital, and will be allocated to either an experimental group or a control group. The experimental group will be treated using fluoroscopy-guided acupotomy and the control group will be treated using the conventional acupotomy method. Results: The primary outcome measure will be identification of a cross-section area of the median nerve measured by ultrasonography, and the secondary outcome measure will be the alleviation of pain measured by the Visual Analogue Scale, improvement in the Nerve Conduction Study, Tinel test, Phalen's test, EuroQol 5-dimension scale, and Boston Carpal Tunnel Questionnaire score. Safety components will be measured by monitoring vital signs, electrocardiographs, blood tests, general chemical tests, urine tests and pregnancy tests. In addition, observations for adverse effects will be performed during the trial. Conclusion: This study will provide a more effective, and less harmful way of treating carpal tunnel syndrome compared with conventional acupotomy. Fluoroscopy-guided acupotomy will help practitioners to be accurate in direction and depth of the needle for treating carpal tunnel syndrome.

• Physical Therapy Rehabilitation Science
• /
• 제8권1호
• /
• pp.1-7
• /
• 2019

Objective: The aim of this study was to evaluate the validity and reliability of using static surface electromyography (sEMG) on persons with neck pain and in healthy adults. Design: Cross-sectional study. Methods: Twenty-two female participants with neck pain and thirty healthy adults in the age group of 20-65 years were recruited in this study. To evaluate the validity and reliability of sEMG in subjects with neck pain, the subjects'characteristics were recorded and the Visual Analog Scale (VAS) and Neck Disability Index (NDI) were examined in addition to sEMG and algometer tests being carried out on the subjects. The site for using the sEMG and algometer was the upper trapezius. sEMG test-retest reliability was measured by intraclass correlation coefficients (ICCs). Independent t-tests were used to analyze the differences in the dependent variables between subjects with neck pain and healthy adults. The Pearson correlation coefficient was used to examine the linear relationship between measured variables. Results: sEMG and algometer tests were reliable according to the test-retest reliability results in subjects with neck pain and healthy adults (ICC=0.815-0.979). The results of this study showed that there were significant differences in respect to age, VAS, sEMG and algometer tests between persons with neck pain and healthy adults (p<0.05). The VAS and NDI were statistically correlated with sEMG and algometer results (p<0.05). Conclusions: In this study, we investigated the clinical usefulness of the static sEMG test in evaluating the pain scale of persons with neck pain with high reliability and validity.

• Geomechanics and Engineering
• /
• 제24권4호
• /
• pp.389-397
• /
• 2021

Pile foundation is a typical form of bridge foundation and viaduct, and large-diameter rock-socketed piles are typically adopted in bridges with long span or high piers. To investigate the effect of a mountain slope with a deep overburden layer on the bearing characteristics of large-diameter rock-socketed piles, four centrifuge model tests of single piles on different slopes (0°, 15°, 30° and 45°) were carried out to investigate the effect of slope on the bearing characteristics of piles. In addition, three pile group tests with different slope (0°, 30° and 45°) were also performed to explore the effect of slope on the bearing characteristics of the pile group. The results of the single pile tests indicate that the slope with a deep overburden layer not only accelerates the drag force of the pile with the increasing slope, but also causes the bending moment to move down owing to the increase in the unsymmetrical pressure around the pile. As the slope increases from 0° to 45°, the drag force of the pile is significantly enlarged and the axial force of the pile reduces to beyond 12%. The position of the maximum bending moment of the pile shifts downward, while the magnitude becomes larger. Meanwhile, the slope results in the reduction in the shaft resistance of the pile, and the maximum value at the front side of the pile is 3.98% less than at its rear side at a 45° slope. The load-sharing ratio of the tip resistance of the pile is increased from 5.49% to 12.02%. The results of the pile group tests show that the increase in the slope enhances the uneven distribution of the pile top reaction and yields a larger bending moment and different settlements on the pile cap, which might cause safety issues to bridge structures.

• 대한조선학회논문집
• /
• 제59권5호
• /
• pp.262-270
• /
• 2022

The emergence of new concept ships, such as autonomous ships, has drawn much attention on the manoeuvrability of ships because of the safe navigation and operation of ships. Although the manoeuvrability of KRISO Container Ship(KCS) has been frequently reported, there have been few documents of representative manoeuvre cases conducted in various methods by one institute. This paper presents the manoeuvrability of the ship in 1/42.0 model scale by 3 methods: free running model tests, horizontal planar motion mechanism tests, and computational fluid dynamics analysis. KRISO reports KCS manoeuvre data: 35° turning circle tests and 20/20(10/10) zigzag manoeuvring tests. In addition, a simple formula for integrating and comparing manoeuvre indices, Manoeuvrability Comparing Simple Index(MCSI), is proposed.

• 한국지반공학회논문집
• /
• 제22권12호
• /
• pp.33-43
• /
• 2006

직항타공법에서 사용되는 해머 쿠션의 재질 차이가 항타시 주변 지반의 진동과 발생 소음 및 에너지 전달효율에 미치는 영향을 실내 모형시험을 통해 평가하였다. 항타 과정을 모사할 수 있는 모델 말뚝과 항타시스템 및 스트레인 게이지와 홉킨슨 바(Hopkinson bar)를 이용한 에너지 전달효율 측정장치를 제작, 구성하였다. 해머 쿠션 재질로는 상용의 해머 쿠션재인 Micarta 이외, 현장에서 다수 사용하는 Plywood, Polyurethane, Rubber(SBR), Silicone rubber 등의 5가지 재료를 선정하여 항타시험을 실시하였다 항타시험결과 쿠션 재료별 에너지 전달효율은 (1)Micarta, (2)Polyurethane, (3)Plywood, (4)Rubber(SBR), (5)Silicone rubber의 순이었다. 또한 에너지 전달효율이 높은 쿠션재료가 음압레벨의 평균치 또한 높은 비례관계를 보였다. 항타 종료후 말뚝 정재하시험을 실시하여 말뚝의 지지력과 축하중전이 특성을 비교, 분석한 결과 Micarta와 Polyurethane이 다른 쿠션재료에 비해 높은 지지력 값을 보였다.