• 제목/요약/키워드: Back moment test

검색결과 29건 처리시간 0.027초

모래지반에서 측방변형을 받는 무리말뚝의 실험적 연구 (The Study of Group Piles under Lateral Soil Movement in Sand by Model test)

  • 배종순;김성호;권민재
    • 한국지반공학회논문집
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    • 제22권10호
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    • pp.165-172
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    • 2006
  • 본 연구에서는 합천사에 매설되어 측방변형을 받는 무리말뚝의 거동특성을 분석하였다. 무리말뚝의 위치, 말뚝의 간격과 말뚝배열이 미치는 무리말뚝의 영향을 알고자 하였다. 실험결과는 다음과 같다. 무리말뚝에서는 모멘트 형상은 단독말뚝과 유사하나 최대 휨모멘트의 발생깊이가 깊어지고, 그 크기는 감소하였다. 말뚝의 중심간격이 증가할수록 최대휨모멘트비$(R_M)$와 수평력분담비$(R_F)$는 증가하였다. 지반변형에 따른 $R_M$은 열방향에서는 후열, 전열, 중간열의 순으로 크게 나타났고 줄방향에서는 내측보다 외측이보다 크게 나타났다.

자동차 시트 프레임 구조의 내구성 향상 설계에 관한 연구 (A Study on the Durability Design of an Automotive Seat Frame)

  • 우창수;조현직;구정서;권재도
    • 한국자동차공학회논문집
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    • 제12권4호
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    • pp.50-57
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    • 2004
  • Structural analysis and fatigue tests have been performed to develop design and evaluation technologies of automotive seat frames. Under the back moment loading condition, the numerical simulation unveiled the maximum stress up to the yield strength at the side frame bracket. To measure the stresses under the test condition, strain gauges were attached to some weakest points of the side frames. the measured strains are in good agreements with the CAE results. On the other hand, some fatigue tests have been performed using the side frame bracket specimens made of various welding types to evaluate their durabilities. From the fatigue tests and the numerical analyses, it was recommended that the bracket welding position should be moved upward.

Kinematic Analysis of Back Somersault Pike According to Skill Level in Platform Diving

  • Park, Jiho;Yoon, Sukhoon
    • 한국운동역학회지
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    • 제27권3호
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    • pp.157-164
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    • 2017
  • Objective: The purpose of this study was to investigate kinematic differences in back pike somersault in platform diving according to skill level and to apply the findings to improve performance. Method: Korean divers participating in this study were divided into a skilled group (age: $21.6{\pm}4.16y$, height: $1.68{\pm}0.03m$, weight: $62.0{\pm}3.94kg$, career: $12.6{\pm}5.13y$) and a less-skilled group (age: $20.6{\pm}2.7y$, height: $1.72{\pm}0.05m$, weight: $64.8{\pm}6.76kg$, career: $12.2{\pm}2.49y$) and an independent t-test was performed to analyze differences between groups at the moment of takeoff. Results: The two groups showed significant differences in displacement and velocity of center of mass (COM), takeoff angle, hip joint angle, knee joint angular velocity, and hip joint angular velocity at the takeoff (p<.05), and significant differences in displacement of COM, hip joint, and ankle joint during flight (p<.05). Conclusion: For a successful back pike, the COM should rise quickly in the vertical direction and the hip joint angle and angular velocity should increase. To improve performance, the back pike turn should be practiced on the ground before an attempt on a 10-m platform, to stretch the ankle and knee joints and enable quick flexion of the hip joint when turning in flight.

M.S.T로 호전된 요통 환자 1례 보고 (Case Report of Low Back Pain patient treated with Motion Style Treatment)

  • 권승로;유혜경;김규태
    • 대한추나의학회지
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    • 제5권1호
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    • pp.93-100
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    • 2004
  • 본 증례는 요각통 환자에게 다양한 한방치료를 시술하였으나 별무호전인 경우 M.T.S요법을 추가로 시행함으로써 양호한 결과를 보인 임상례이다. 요통환자가 장기간의 치료에도 차도가 없거나 호전에 미미했을 때 물론 의사의 마음에도 불가피하게 수술을 해야 될 것이라는 생각이 떠오르게 된다. 하지만 수술을 해야 할 것인지 혹은 하지 말아야 할 것인지 결정을 내리기 전에 충분히 다른 치료법을 시행해 볼 필요가 있다. 이에 저자는 장기간의 치료에도 차도가 없거나 호전이 미미한 요통 환자에게 M.S.T 요법을 시행할 경우 양호한 결과를 얻으리라 사료되어 보고하는 바이다.

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등맛사지가 개심술 환자의 불안 및 면역반응에 미치는 효과 (The Effect of Slow Stroke Back Massage on Anxiety and Immune Response in the Patients undergoing Open Heart Surgery)

  • 김혜순;이향련
    • 대한간호학회지
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    • 제28권4호
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    • pp.980-991
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    • 1998
  • The purpose of this study was to examnin the effect of slow stroke back massage(SSBM) on anxiety and immune response in patients undergoing open heart surgery and to compare the effect of 5-minutes with 10-minutes SSBM. Among the sixty-four patient subjects, twenty-one were one experimental group receiving massage for 10-minutes, twenty for the other experimental group receiving massage for 5-minutes and twenty-three for the control group. Subjects were admitted at Hospitals in Inchon and Puchon for open heart surgery. This study was carried out from October 10, 1997 to May 10, 1998. The levels of anxiety were measured by the Visual Analogue Scale(VAS), Trait anxiety scale, systolic and diastolic blood pressure, pulse rate, blood cortisol and the levels of immune response were measured by the blood T-lymphocyte and Natural killer cell. Study measurements were taken before and after SSBM on the 1st post operative day. Data were analyzed using x$^2$ test, oneway ANOVA, paired t-test, t-test and Pearson product moment correlation. The results were summarized as follows : 1. After SSBM, VAS anxiety level, systolic and diastolic blood pressure and pulse rate of the experimental group were decreased significantly than those measurements before the SSBM. After SSBM, significant difference in the VAS anxiety level, systolic blood pressure and pulse rate between the experimental and control groups were found. 2. After SSBM, the blood cortisol of the experimental and control groups were increased significantly compared with before SSBM. But the significant difference in blood cortisol between the two groups was not found. 3. After SSBM, the blood T-lymphocyte percentages of the experimental and control groups were decreased signigicantly and blood Natural killer cell percentages of the two groups were increased compared with before SSBM. But significant difference in blood T-lymphocyte and Natural killer cell percentages between the two groups was not found. 4. Significant difference in VAS anxiety level, systolic and diastolic blood pressure, pulse rate, blood cortisol, blood T-lymphocyte and Natural killer cell percentages between SSBM for 5 minutes and SSBM for 10 minutes were not found. Based upon the results, this study concludes that the slow stroke back massage for 5 minutes is a useful intervention that decreases anxiety and produces relaxation in patients undergoing open heart surgery.

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신경망을 이용한 내용기반 영상 분류 (A Content-Based Image Classification using Neural Network)

  • 이재원;김상균
    • 한국멀티미디어학회논문지
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    • 제5권5호
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    • pp.505-514
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    • 2002
  • 본 논문에서는 내용기반 영상 분류를 위한 방법론으로써 신경망을 이용한 방법을 제안한다. 분류 대상 영상은 인터넷상의 다양한 영상들 중에서 전경과 배경의 구분이 있는 객체 영상이다. 전처리 과정에서 영역 분할을 이용하여 영상 내에서 배경을 제거하고 객체 영역을 추출한다. 분류를 위한 특징은 웨이블릿 변환 후 푸출된 형태 특징과 질감특징을 이용한다 추출된 특징 값들을 이용하여 영상들에 대한 학습패턴을 생성하고 신경망 분류기를 구성 한다. 신경망의 학습 알고리즘은 역전파 알고리즘을 사용한다. 가장 효과적인 질감특징을 선 택 하기 위한 실험에서는 대각 모멘트가 가장 높은 분류률을 보여 주었다. 배경을 제거 하고 대각 모멘트를 특징으로 사용하여 실험하였을 때, 30종류에서 각 10개씩 총 300개의 학습 데이터와300개의 테스트 데이터에 대하여 각각 72.3%와 67%의 정분류률을 보였다.

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평행식 진동탄환 암거 천공기의 연구 (IV)(V)-실기 설계 제작 및 보장실험-Development of Balanced-Type Oscillating Mole Drainer(IV)(V)

  • 김용환;이승규;서상용
    • Journal of Biosystems Engineering
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    • 제2권1호
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    • pp.7-24
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    • 1977
  • This paper is the forth and fifth one of the study on balanced type oscillating mole drainer. In the light of the results from previous reports about the model tests, some design criteria were established and a prototype machine was set up for experimental purpose. Motion characteristics and functionof the each parts of the machine were checked and analyzed. After that, performance tests of the prototype machine were carried out in thefield. Obtained results are summarized as follows ; 1. Ten centimeter of the bullet diameter was determined so as to be able to attach it to the tractors with capacity of 30 PS to 40 PS. 2. To maintain the balance between the moments of the front shank and rear shank, the oscillating amplitude of the rear bullet was determined to be larger than that of the front bullet. At the same time , the oscillating direction of the rear bullet was designed with the inclines of ten to thirty degrees. 3. An octagonal dynamo transduced was developed for measuring the compressive force of the upper link is measuring the draft force of the machine. Acceptable linear relationship between forces and strain responses from O.D.T. was obtained. 4. Analysing the balancing mechanism of the acting part of the machine , it was found that the total draft force of the machine was equal to the difference between the sum of the draft force produced from the right and left side bending moments of the lower drawber and the compressive force on the upper link. 5. There are acceptable linear relationship between the strain and twisting moment by driving shaft, and between strain and shank moment. Above results enable us to carry out the field experiment with prototype machine. 6. When the test machine was used in the field, it was possible to reduce the oscillating acceleration by forty percent in average as compared it with the single bullet mole drainer. 7. When the test machine was used under the oscillating condition, the dratt torce was reduced by 27 percent to 59 percent as compared it with the test machine under non-oscillating condition, while the draft force was increased by 7 percent to 20 percent as compared it with the mole drainer having oscillating single bullet. The reasoning behind this fact was considered as the resistance force due to the rear shank and bullet. 8. As the amplitude and frequency of the bullet were increased, the torque was increased accordingly. This tendency could be varied with the various characteristics of the given soils. And the larger frequency and amplitute, the more increasing oscil\ulcornerlating power but decreasing draft brce were needed, and draft force was increased as the velocity was increased.9. When the amplitude of the rear bullet was designed to be larger than that of the front bullet, the minimum value of the moment was lowered and oscillating acceleration was reduced. And when the oscillating direction of the rear bullet was declined back\ulcornerwards, oscillating acceleration was increased along with the increasing angle of decli\ulcornernation. When the test machine was operated in high speed, the difference between maximum moments and minimum ones became narrow. This varying magnitude of moments appeared on the moment oscillogram seems to be correlated to the oscillating acceleration and draft force. 10. From the analysis of variance, it was found that those factors such as frequency, amplitude, and operating velocity significantly affected in the oscillating acceleration, the draft resistance, the torque, the moment, and the total power required. And interaction between frequency and amplitude affected in the oscillating acceleration. 11. Within the given situation of this study, the most preferable operating conditions of the test machine were 7 Hz in oscillating frequency, 0.54 m/sec in operating velocity, and 39.1 mm in oscillating amplitude of front and rear bullets. However, it is necessary to select the proper frequency and magnitude of oscillation depending on the soil properties of the field in which the mole drainer is practiced by use of a bal1nced type oscillating mole drainer. 12. It is recommended that a comparative study of the mole drainers would be performed in the near future using two separate balanced oscillating bullet with the one which is operated by oscillating the movable bullet in a single cylinder or other balanced type which may be single oscillating bullet with spring, damper or balancing weight, and that of thing. To expand the applicability of the balanced type oscillating mole drainer in practical use, it is suggested to develop a new mechanism which perform mole drain with vinyl pipe or filling material such as rice hull.

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경호무도의 태권도 주먹 지르기 동작 운동학적 분석 (The Kinematic Analysis of Jumeok Jireugi in Taekwondo of Security Martial Arts)

  • 이세환;양영모
    • 시큐리티연구
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    • 제31호
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    • pp.187-207
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    • 2012
  • 본 연구는 태권도의 기본동작인 주춤서기 자세에서의 주먹 지르기 동작을 3차원 입체영상분석을 통해 유형별로 운동학적 변인인 시간, 속도, 각도, 각속도, 각가속도 등을 분석하여 유형별 특성을 알아보고 올바른 주먹 지르기 동작의 지도방법을 제시하고자 하였다. 이를 위해 대학교 경호무도 태권도 경호무도시범단 3인을 대상으로 실시하였고 다음과 같은 결론은 도출 하였다. 1. 지르기 동작 수행시간 : 각 유형(Type)별 주춤서기 자세에서 주먹 지르기 동작 수행시간은 1구간에서 $0.24{\pm}0.07s$$0.42{\pm}0.08s$로 유형(Type)1의 주먹 지르기 동작 수행시간이 빠르게 나타났지만 전체 수행시간에 대한 구간별 비율은 유형(Type)2의 테이크 백(take back)이 더 짧은 것으로 나타났다. 2. 선속도 및 선가속도 변인 : 각 유형(Type)의 국면별 선속도는 모두 다르지만 가장 높은 선속도는 각 유형(Type)의 임팩트 순간 이라 할 수 있으며, 유형(Type)2의 임팩트 순간인 3국면에서 가장 높은 선속도가 나타났다. 3. 관절각 변인 : 유형(Type)별 주먹 지르기 동작이 관절의 각은 임팩트 국면인 유형(Type)1의 주먹 지르기 동작과 유형(Type)2의 주먹 지르기 동작에서 외형적으로 큰 차이가 나지 않지만 유형 (Type)2의 주먹 지르기 동작이 관절각의 변화가 다양해 역동적인 자세를 취하고 있다. 4. 각속도 및 각가속도 변인 : 유형(Type)1의 주먹 지르기 동작이 임팩트 순간인 3국면의 고관절, 견관절, 손목관절 의 각속도는 각각 $0.79{\pm}0.02deg/s$, $0.91{\pm}0.04deg/s$, $5.24{\pm}0.09deg/s$ 로 나타났으며, 유형(Type)2의 주먹 지르기 동작이 임팩트 순간인 4국면의 고관절, 견관절, 손목관절의 각속도는 각각 $1.32{\pm}0.03deg/s$, $0.21{\pm}0.03deg/s$, $4.98{\pm}0.08deg/s$로 나타났다. 유형(Type)2의 임팩트 순간인 3국면의 오른쪽 손목관절의 각가속도의 변화를 보면 $176.24{\pm}1.11deg/s^2$로 유형(Type)1의 임팩트 순간의 각가속도 보다 더 큰 속도의 변화를 보였다.

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사질토 지반에서 말뚝의 수평거동 (Lateral Behavior of Sin811e and Group Piles in Sand)

  • 김영수;김병탁
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.3-44
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    • 1999
  • This paper discusses the lateral behavior of single and group piles in homogeneous and non-homogeneous(two layered) soil. In the single pile, the model tests were conducted to investigate the effects on ratio of lower layer height to embedded pile length, ratio of soil modules of upper layer to lower layer, boundary rendition of pile head and tip, embedded pile length, pile construction condition, ground condition with saturate and moisture state in Nak-Dong river sand. Also, in the group pile, the model tests were to investigate the effects on spacing-to-diameter ratio of pile, pile array, ratio of pile spacing, boundary condition of pile head and tip, eccentric load and ground condition. The maximum bending moment and deflection induced in active piles were found to be highly dependent on the relative density, pile construction condition, boundary condition of pile head and tip. Based on the results obtained, it was found that the decrease of lateral bearing capacity in saturated sand was in the range of 31% - 53% as compared with the case of dry sand. Also, in the group pile, a spacing-to-diameter of 6.0 seems to be large enough to eliminate the group effect for the case of relative density of 61.8%, and 32.8%, and then each pile in such a case behaves essentially the same as a single pile. In this study, the program is developed by using the modified Chang method which used p - y method and the exact solution of governing equation of pile and it can be used to calculate the deflection, bending moment and soil reaction with FDM in non-homogeneous soil. In comparing the modified Chang method with field test results, the predict results shows better agreement with measured results in field tests.

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살충제 개발을 위한 생물검정법의 확립 I. 각종 유기 용매가 곤충의 독성과 약해 및 화합물의 용해성에 미치는 영향 (Establishment of Bioassay System for Developing New Insecticides I. Effects of Organic Solvents on the Toxicity against Insects, Phytotoxicity and Solubility of Compounds)

  • 안용준;조광연
    • 한국응용곤충학회지
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    • 제31권2호
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    • pp.182-189
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    • 1992
  • 신규 설충성물질 개발의 전제조건이 되는 용매의 선택을 위하여, 아세톤의 9종의 유기용매를 수종의 곤충에 대한 독성과 식이식물 및 화합물의 용해성에 미치는 영향을 엽침지법과 분무법으로 평가하였다. 각종 용매의 공시충에 대한 치사독성과 용매의 이화학적인 성질과는 뚜렷한 상관관계가 보이지는 않았으나, 분무법 처리시 벼멸구의 경우 밀도가 높을수록, 배추좀나방의 경우에는 증기압이 낮을수록 공시충에 대한 치사독성이 높았으나, 비등점, 쌍극자모멘트, 유전율, 표면장력, 점도와는 상관관계를 보이지 않았다. 처리 방법에 있어서는 분무처리가 엽침지법보다 더 높은 치사독성을 나타내었다. 약해와 용매의 이화학적 성상 역시 명확한 상관관계를 보이지 않았으나, 엽침지법의 경우 수도에 있어서 유전율이 낮을수록 약해가 심하였으며, 분무법 처리시에는 쌍극자 모멘트가 높을수록 약해가 심하였으나 기타의 이화학적 성상과는 상관관계를 보이지 않았다. 엽침지처리가 분무처리에 비하여 강한 약해를 유발하였다. 합성 화합물과 식물체 메탄올 추출물은 아세톤에 대한 용해성이 양호하여 생물검정시 5% 아세톤수용액이 다량의 화합물을 검정하는데 적합하였다.

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