• 제목/요약/키워드: accumulated fatigue

검색결과 108건 처리시간 0.023초

근전도(筋電圖)를 이용한 착좌시(着座時) 하지동작(下肢動作)의 근특성분석(筋特性分析) 연구 (Analysis of Muscular Characteristics of Lower Extremity Movement for Seated Operators by EMG)

  • 황규성
    • 대한산업공학회지
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    • 제24권2호
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    • pp.261-278
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    • 1998
  • The paper represented the lower extremity muscle model as four rigid-body segments: trunk, shank, and foot. We transformed their tibial data into our shank data by rotating their tibial X and Y axes by 5.483 degrees, so the revised coordinate data used to translating the origin of their tibial reference frame to our shank reference frame. According to weight of subject, physiological cross-setional area(PCSA) of each lower extremity muscle was calculated by scaling those data by Brand. The objectives of this paper are to investigate the variations of the recruitment patterns of the lower extremity muscles, and to analyze the changes of the role assigned to each muscle during the seated foot operation. For exertion levels, the transition point of type F motor unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern and the changes of the role assigned are identified in the continuous exertion, by analyzing the electromyogram changes due to the accumulated muscle fatigue. This study can be used to design and to assess the pedals and foot-related equipments design.

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중회귀분석을 통한 콘크리트궤도 레일 휨응력 예측식 (The Prediction Equation for Bending Stress of Rail in Concrete Track by the Linear Multiple Regression Analysis)

  • 성덕룡;임형준;이동욱;김박진;박용걸
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.315-323
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    • 2010
  • 장대레일 교체주기는 자갈궤도 레일두부 표면요철과 레일 휨피로의 상관관계 분석을 통해 산정되었다. 본 연구에서는 국내 도시철도(서울메트로) 콘크리트궤도에서 레일두부 표면요철량에 따른 레일 휨응력을 측정하였다. 또한, 콘크리트궤도 레일두부 표면요철, 속도와 레일 휨응력의 상관관계를 분석하였다. 결론적으로, 중회귀분석을 통해 운행속도(U), 표면요철(v, w)에 따른 레일 휨응력(Y) 예측식을 도출하였다. 본 연구결과는 콘크리트궤도 장대레일 교체주기를 수립하기 위한 기초데이터로 활용이 가능할 것이다.

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A Biomechanical Model of Lower Extremity Movement in Seated Foot Operation

  • Kyu-Sung Hwang
    • 산업경영시스템학회지
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    • 제23권60호
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    • pp.37-46
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    • 2000
  • A biomechanical model of lower extremity in seated postures was developed to assess muscular activities of lower extremity involved in a variety of foot pedal operations. The model incorporated four rigid body segments with the twenty-four muscles to represent lower extremity This study deals with quasi-static movement to investigate dynamic movement effect in seated foot operation. It is found that optimization method which has been used for modeling the articulated body segments does not predict the forces generated from biarticular muscles and antagonistic muscles reasonably. So, the revised nonlinear optimization scheme was employed to consider the synergistic effects of biarticular muscles and the antagonistic muscle effects from the stabilization of the joint. For the model validation, three male subjects performed the experiments in which EMG activities of the nine lower extremity muscles were measured. Predicted muscle forces were compared with the corresponding EMG amplitudes and it showed no statistical difference. For the selection of optimal seated posture, a physiological meaningful criterion was developed for muscular load sharing developed. For exertion levels, the transition point of type F motor unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern is identified in the continuous exertion, by analyzing the electromyogram changes due to the accumulated muscle fatigue.

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암질병에 따른 암환자의 불편감과 고통에 관한 연구 (A Study on the Symptom Distress and Suffering of Five Major Cancer Patients)

  • 권미형;김분한
    • 종양간호연구
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    • 제3권2호
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    • pp.145-154
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    • 2003
  • Purpose: The study was to furnish basic raw materials that evaluate the efficacy of meatal care according to the form and the relative importance of symptom distress which most of cancer sufferers have been experienced. For that, an investigation of five diverse major cancer symptom distress made a comparison between symptom distress and degree of suffering. Method: Study subjects were 138 inpatients with stomach cancer, lung cancer, hepatocellular carcinoma(HCC), large intestine cancer and breast cancer, except those in the terminal-stage, in 'H' university hospital in Seoul and 'K' center in Ilsan gathered from November 20, 2002 to February 20, 2003. To measure the correlation between feeling of discomfort and agony caused by cancer, 5 point scale (from zero to four), stood on the basis of Symptom Distress Scale (SDS, Rodes & Watson, 1987), was used for this study and the Cronbach's coefficient alpha was 0.95. Accumulated data was analyzed with SPSS 10.0 for window, also used by ANOVA and Duncan's Multiple Range Test. Pearson's Correlation Analysis. Results: 1. Symptom distress of cancer patients was noted and defined in their severity-fatigue, anorexia, pain, depression, dyspepsia, changing appearance and nausea. The degree of symptom distress was fatigue, dyspepsia, depression, anorexia, pain, changing appearance and the degree of suffering was nausea, pain, anorexia, dyspepsia, vomiting, breathing difficulty, changing appearance and fatigue. 2. Examining the difference of degree of symptom distress in each cancer cases, it takes the precedence of them. First, in case of stomach cancer, depression, pain, vomiting and nausea were shown in sequence. In case of lung cancer depression, pain, sleeping problem, anxiety, changing appearance, inattentiveness and vomiting were showed in sequence, depression, changing appearance, sleeping problem, pain in case of HCC, depression, pain in case of large intestine cancer and lastly in case of breast cancer changing appearance, depression, pain and anxiety were shown in sequence. The category of the degree of symptom distress that has a signifiant difference was anorexia, activity discomfort, fatigue, constipation or diarrhea, breathing difficulty, dyspepsia, caughing, fever or chillness, scotoma and urinary disorder. Verifying the highest degree of symptom distress in each cancer cases, anorexia was 1.94(F=4.00, p<.01) in stomach cancer, activity discomfort was 0.97(F=3.08, p<.01) in lung cancer and HCC, fatigue was 2.32(F=4.64, p<.01) in HCC, constipation or diarrhea was 1.83(F=22.31, p<.001) in large intestine cancer, breathing difficulty was 1.83(F=4.00, p<.01) in lung cancer, dyspepsia was 2.69(F=9.98, p<.001) in stomach cancer, coughing was 1.53(F=20.49, p<.001) in lung cancer, fever or chillness was 1.23(F=6.88, p<.001) in lung cancer, scotoma was 1.20(F=3.02, p<.05) in lung cancer and urinary disorder was 1.54(F=11.56, p<.001) in HCC. 3. Examining the difference degree of suffering on cancer cases, the result was as follows; depression of lung cancer was 1.17(F=3.76, p<.01), anorexia of stomach cancer was 1.61(F=3.89, p<.01), constipation or diarrhea of large intestine cancer was 1.42(F=10.43, p<.001), changing appearance of breast cancer was 1.65(F=5.43, p<.001), breathing difficulty of lung cancer was 2.27(F=18.57, p<.001), dyspepsia of stomach cancer was 1.97(F=13.56, p<.001), coughing of lung cancer was 1.70(F=22.07, p<.001), fever or chillness of lung cancer was 1.13(F=4.41, p<.01), scotoma of lung cancer was 0.87(F=3.34, p<.05), anxiety of lung cancer was 0.87(F=4.50, p<.001) and urinary disorder of HCC was 1.43(F=16.71, p<.001). 4. In consequence, comparing between symptom distress and degree of suffering on cancer patients undergoing chemotherapy, lung cancer patients showed the highest feeling of discomfort following stomach cancer, HCC, breast cancer and large intestine cancer(F=2.88, p<.05). On those undergoing radiotherapy, lung cancer, HCC, breast cancer, large intestine cancer was in sequence(F=3.78, p<.05) and those resisting radiotherapy, lung cancer, HCC, stomach cancer, large intestine cancer and breast cancer was in sequence(F=2.72, p<.05). 5. Correlation between symptom distress and degree of suffering on cancer patients was generally significant. Conclusion: this study not only defines a significant correlation between symptom distress and degree of suffering but also proffers basic data to evaluate the efficient meatal care depending upon diverse spectrums of symptom distress and degree of suffering.

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지능형 대퇴 의족 사용자의 의도 검출을 통한 제어 모드 변경 기법에 관한 연구 (A Study on the Mode Change Technique of Intelligent Above-Knee Prosthesis Based on User Intention Capture)

  • 신진우;엄수홍;류중현;이응혁
    • 전기전자학회논문지
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    • 제24권3호
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    • pp.754-765
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    • 2020
  • 최근 다양한 환경에서의 보행과 특정 동작에서 해당 모드를 지원하는 지능형 대퇴 의족이 개발되고 있다. 계단 상행, 하행과 같은 특정 제어는 동작 전 모드를 변경해야하기 때문에 사용자의 의도를 기반으로 제어명령을 구분하는 기법이 필요하다. 따라서 본 논문에서는 지능형 대퇴 의족 시스템에서 사용자의 의도에 기반하여 다양한 제어명령을 구분할 수 있는 기법을 제안한다. 제안하는 기법은 근전도 신호의 보상이 필요하다고 판단되는 경우, 평상시의 근전도 신호의 세기 및 주파수 성분과 압력센서로 추정한 근육의 부피 정도의 상관관계를 이용하여 근전도 신호를 보상하는 것이며 실험을 통해 근피로가 축적되어 있는 상황에도 사용자의 의도를 정확하게 검출하는 것을 확인하였다. 향상된 사용자 의도 검출 기법을 통해 정해진 시간 내 근육의 수축 횟수를 기반으로 5개의 제어모드를 구분할 수 있도록 하였으며 실험 결과 운동 후 근피로로 인해 근신호의 세기가 평시와 다를 경우에도 근신호 보상을 통해 97.5%의 정확도를 갖는 것을 확인하였다.

연속주행시간과 졸음사고간 통계적 상관관계 분석 (The Statistical Correlation Between Continuous Driving Time and Drowsy Accidents)

  • 김덕녕;김수진;최재헌;조종석
    • 대한교통학회지
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    • 제35권5호
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    • pp.423-433
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    • 2017
  • 최근 5년간 집계된 고속도로 교통사고자료에 따르면 전체 사고건수의 20%, 사망자수의 30%가 졸음운전으로 발생되고 있다. 졸음사고는 운전자의 피로도가 누적되었을 때 주행능력을 상실한 운전자의 인적 요인으로부터 발생되며, 정성적으로 체감되는 피로도는 운전자의 연속주행시간을 통해 간접적으로 분석될 수 있다. 본 연구는 2시간 이상 연속 주행한 차량의 비율과 해당 링크에서 집계된 졸음사고간의 통계적 상관관계를 규명하는데 주된 목적을 둔다. 이를 위해 네비게이션 주행 궤적 자료를 활용하여 링크별 연속주행차량의 비율을 산출하였으며, 중부내륙 고속도로의 링크별 졸음사고 건수, 교통량, 구간길이를 변수로 하는 안전성능함수를 추정하였다. 본 연구에서는 다양한 형태의 안전성능함수가 추정되었으며, 도출된 통계치의 비교를 통해 연속주행시간과 졸음사고 발생간의 통계적 상관성이 다각적으로 분석되었다. 본 연구결과는 최근 화물차 및 여객버스 운전자의 연속주행을 단속하는 제도에 학술적 근거를 제공할 수 있을 것으로 판단하며, 궤적자료의 양적 질적 확대를 통해 향후 졸음방지 시설물의 설치 위치를 결정하는 전략 수립에 활용 가능할 것으로 기대한다.

간경변으로 입원한 환자 33례에 대한 분석 (The Clinical Study on 33 Cases of Liver Cirrhosis)

  • 최서형;심민;김태수;민지연;최영규
    • 대한한방내과학회지
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    • 제26권4호
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    • pp.836-843
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    • 2005
  • Objective : Liver cirrhosis is a disease of the liver in which normal cells are replated by scar tissue. Chronic liver disease and liver cirrhosis are the foutth ranked causes of death in Korea. However, clinical data on liver cirrhosis is not accumulated in oriental medicine. Therefore, clinical characteristics of 33 liver patients admitted to Hana Oriental Hospital from May 2004 to May 2005 were studied. Methods : Clinical characteristics of liver cirrhosis, such sex, age, causes, Child-Pugh class, chief complain, abdomen ultrasonography, disease duration, past history, blood test and urinalysis were reviewed. Results : The results of this study were as follows: 1 The distribution of sex and age in our study is similar to already reported statistics. 2. Hepatitis B and alcohol are the major factors to cause the liver cirrhosis. Diabetes and hypertention contribute more to cause than they have in previous histories. 3. Major symptoms are following: fatigue 87.9%, ascites 84.8%, jaundice 78.8%, leg edema 72.7%, dyspepsia 45.5%. 4. Most liver cirrhosis patients have pancytopenia. Standard Deviation accentuates the big differences between total bilirubin and serum amonia. 5. In urinalysis, Urobilinogen 19 patients (57.6%), bilirubin 12 patients (36.4%), blood 15 patients (45.5%) are positive. 11 cases of 15 in blood positive results scored $3{\sim}4+$. Contusions : In oriental medicine, it will be necessary to research and develop oriental medical therapies for liver disease including liver cirrhosis.

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텍스쳐 분석에 의한 피혁 등급 판정 및 자동 선별시스템에의 응용 (Automatic Leather Quality Inspection and Grading System by Leather Texture Analysis)

  • 권장우;김명재;길경석
    • 한국멀티미디어학회논문지
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    • 제7권4호
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    • pp.451-458
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    • 2004
  • 육안에 의한 피혁의 등급 판정 과정은 장시간 시 피로에 의한 일관성 결여로 인해 판정 결과에 대한 신뢰성을 주지 못한다. 따라서 피혁의 품질을 결정하기 위한 객관적인 지표와 이를 기준으로 등급 판정 과정의 자동화가 필요하다. 본 논문에서 적용된 피혁 자동 선별 시스템은 피혁에 대한 정보를 취 득하는 과정과 이들로부터 등급을 판정하는 과정으로 구성된다. 피혁의 품질은 조밀도와 결함의 종류 및 분포도와 같은 피혁의 특성에 의해 결정된다. 본 논문에서는 디지털 카메라에 의해 획득된 흑백 영상으로부터 피혁의 조밀도 및 결함을 추출하여 피혁의 등급을 판정하는 알고리즘을 제안한다. 조밀도는 퓨리에 스펙트럼이 존재하는 영역의 넓이 및 가로, 세로 비율로서 계산된다. 그리고 결함은 전처리 과정을 거친 영상으로부터 검색 윈도우를 사용하여 윈도우에 해당하는 픽셀들의 히스토그램 분포의 특징에 의해서 검출된다. 피혁 전체에 대한 특성들은 피혁의 등급을 판정하는 지표로 사용되며 다른 분야에서의 인간의 시각 검사를 대체 할 수 있으리라 판단된다.

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산림작업(山林作業)에서 OWAS기법(技法)을 이용(利用)한 작업자세(作業姿勢) 분석(分析) (Analysis of Working Posture Using OWAS in Forest Work)

  • 이준우;박범진
    • 한국산림과학회지
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    • 제90권3호
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    • pp.388-397
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    • 2001
  • 작업환경의 개선이 불가능한 임업에 있어서 올바른 작업자세는 불필요한 체력의 낭비 및 누적된 특정부위에서 피로로 유발되는 상해발생 예방, 체력 저하로 인한 주의력 감소로 야기되는 휴먼에러 예방 등의 직접적인 효과를 가져 올 수 있을 것으로 판단된다. 이에 본 연구는 OWAS분석기법을 이용하여 체인톱을 이용한 간벌작업, 체인톱을 이용한 피해목벌채작업, 손톱을 이용한 임내정리작업, 낫을 이용한 덩굴제거작업, 고지절단톱을 이용한 가지치기작업, 낫을 이용한 어린나무가꾸기작업에 대하여 작업자세분석을 실시하였다. 주요 작업 중, 체인톱과 낫을 이용한 작업에서 근골격계에 약간의 해를 끼침으로 가까운 시일 내에 작업자세의 교정이 필요한 수준(수준 III)의 코드비율과 근골격계에 매우 심각한 해를 끼침으로 즉각적인 작업자세의 교정을 필요로 하는 수준(수준 IV)의 코드비율이 높게 조사되었다. 체인톱을 이용한 벌목작업에서 미숙련자와 숙련자의 작업자세를 비교해 본 결과, 수준 IV의 경우 중간 수준의 숙련자가 5.1%로 14.1%의 미숙련자 보다 낮은 것으로 조사되었다.

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저나트륨혈증성 탈수증으로 진단된 소아 부신백질이영양증 1례 (A Case of Adrenoleukodystrophy Diagnosed as Hyponatremic Dehydration)

  • 이상헌;김형진;권영세;김순기;이지은
    • 대한유전성대사질환학회지
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    • 제14권1호
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    • pp.66-70
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    • 2014
  • X-linked adrenoleukodystrophy (ALD) is a uncommon metabolic disorder which derived by peroxismal ${\beta}$-oxidation and elevation of serum very long chain fatty acid (VLCFA). VLCFA is mainly accumulated in the myelin of the central nervous system and adrenal cortex, by which the expressed symptoms of this disease are mainly neurologic and endocrinologic (such as adrenal insufficiency). The mutations in the ABCD1 gene causes X-linked ALD, nevertheless its phenotypes and genotypes are poorly coordinated. We report the case of a 12-year-old boy with X-linked ALD who developed vomiting, fatigue and poor oral intake. Severe dehydration and hyponatremia were found in initial physical examination and laboratory test, but his motor/sensory nerve function and mental status were completely normal. We diagnosed ALD with diffuse high-intensity signal in both parietotemporal cerebellar white matter in brain MRI and elevated serum VLCFA. Later, we confirmed a novel c.1635-1G>A (IVS6-1G>A) mutations of the ABCD1 gene. With the discrepancy between its phenotypes and genotypes, various phenotypes could be seen in X-ALD patient. Careful examination and further studies for these patients will be needed.