• 제목/요약/키워드: Endurance evaluation

검색결과 151건 처리시간 0.023초

n/m 흐름작업의 Heuristic 기법에 관한 연구 (A Study on the Heuristic Algorithm for n/m Flow- Shop Problem)

  • 이근부
    • 산업경영시스템학회지
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    • 제5권6호
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    • pp.41-48
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    • 1982
  • This paper analyzed md developed flow - shop sequencing heuristic method. The essence of the heuristic approach is in the application of selective routine that reduce the size of a problem. The advantages of this approach are consistency. Speed, endurance and the ability to cope with more data and larger systems than is humanly possible, In recent years many heuristic procedures have been suggested for the flow - shop sequencing problem. Although limited comparisons of these procedures have been made, a full scale test and evaluation have not been reported previously. The maximum flow - time criterion is selected as the evaluation criterion is selected as the evaluation criterion of flow - shop's efficiency. The author evaluated these 3 heuristic method's performance. By the evaluation of the result, we can see that the modified methods produce a shorter maximum flow - time than the original methods.

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헛개나무열매 열수추출물 투여에 의한 흰쥐의 지구력 향상 효과 (Improvement in Exercise Endurance by Hovenia dulcis Fruit Hot Water Extract in Mice)

  • 권태형;한준희;이선엽;유근형
    • 한국식품영양학회지
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    • 제33권4호
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    • pp.363-371
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    • 2020
  • This study was designed to evaluate the improvement in exercise endurance by Hovenia dulcis fruit hot water extract (HDWE) for the potential application as a functional food material. The effect was based on the evaluation of the forced-swimming capacity and changes in biochemical parameters in mice. Six-week-old mice were classified into four groups based on a randomized block design: the negative control group, the HDWE 50 mg/kg body weight group, the HDWE 200 mg/kg body weight group, and the 1-octacosanol 50 mg/kg body weight group (n=8 mice per group). The swimming exercise time in the HDWE-50 group was increased at 545±43 sec compared to the control group at 263±28 sec. The HDWE-200 fatigue indicators, lactate acid and ammonia content, decreased to 4.99±0.33 mg/mL and 0.63±0.05 mg/mL, respectively. In addition, the content of glycogen in the liver and muscle tended to increase in the group administered HDWE but was not significant. Likewise, the LDH and glucose contents were increased compared to the control group. The muscle damage indicators ALT (52.7±2.6 U/L) and AST (42.5±5.2 U/L) tended to decrease compared to the control group (76.4±10.2 U/L).

Effects of Gluteus Medius Strengthening Training Using Pressure Biofeedback Unit for Muscle Function and Balance in Stroke Patients

  • Park, Jeong-Ju;So, Hyun-Jeong;Shin, Won-Seob
    • The Journal of Korean Physical Therapy
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    • 제27권4호
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    • pp.221-227
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    • 2015
  • Purpose: The purpose of this study was to examine the impact of gluteus medius (GM) strengthening training using the pressure biofeedback unit for lower extremity muscle function and balance ability in stroke patients. Methods: Twenty-seven stroke patients (14 men, 13 women) volunteered to participate in this study. They were randomly assigned to 3 groups: pressure biofeedback unit GM training, general GM training, and control group. Experimental group 1 performed GM strengthening training using PBU in the sidelying position. Experimental group 2 performed GM strengthening training without PBU in the sidelying position. The training program lasted 4 weeks (20-minute sessions, three times a week). Muscle function was assessed by measuring muscle strength and endurance, and Berg balance scale (BBS), Lateral Reach Test (LRT), and limited of stability (LOS) velocity were measured for evaluation of balance ability. Results: Enhancement of muscle strength and endurance was significantly higher in experimental group 1 than in the other two groups (p<0.05). In comparison of the balance function, experimental group 1 showed a significantly enhanced ability to balance (p<0.05). After the intervention, experimental group 1 showed a significant reduction of LOS velocity in the anterior direction and affected direction (p<0.05). There was no significant difference than the other two groups but a large reduction was observed. Conclusion: These findings suggest that selective gluteus medius strengthening training using the pressure biofeedback unit is effective for lower extremity muscle function and balance ability in stroke patients.

고체 추진제 장시간 물성거동 반응 연구 (A Study of Thermo-rheological Behaviour from Long Term Responses of Solid Composite Propellant)

  • 류태하;김낙현;길태옥;최용규
    • 한국추진공학회지
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    • 제21권1호
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    • pp.8-16
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    • 2017
  • 고체 추진기관이 노즐마개에 의해 외기와의 교환이 완벽히 차단된다면, 구조적 안정성은 제작초기 조건인 내부조성간의 잔류반응(Post Cure, Migration etc.), 그리고 자유공간 내의 산소(또는 산화방지제)와 습기(제습제)와의 반응에 종속된다. 이로부터 발생하는 혼합형 고체추진제의 기계적 특성은 매우 복잡하며, 추진기관은 발사직전까지 일교차/년교차의 끊임없는 열하중을 받게 된다. 본 연구에서는 고체 추진기관의 제조공정인 성형오븐에서 출고 후 저장안정화까지의 거동을 고체추진제의 열유변학적 단순특성을 적용하여 신속하게 산출할 수 있는 방법을 제시하였다. 이를 위해 온도제어 가능한 Endurance Test 장치를 고안 제작하였으며, 추가적으로 점진적 응력과 변형율 증가에 따른 비선형 특성도 검토한다.

Fe-Mn 제진 금속을 적용한 신축이음장치의 피로 내구성 평가 (Evaluation of Fatigue Endurance on Expansion Joint Manufactured Fe-Mn Damping Alloy)

  • 김기익;김영진;안동근;김철환
    • 대한토목학회논문집
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    • 제29권4D호
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    • pp.483-489
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    • 2009
  • 진동 소음을 저감시키는 Fe-Mn 제진 금속을 이용하여 제작된 핑거형 신축이음장치의 피로 내구성을 평가하고자 유한 요소해석과 수직하중 피로시험을 실시하였다. 피로실험은 Fe-Mn 제진금속을 이용한 신축이음장치와 유압가력기(25tonf)를 사용하여 진행되었으며, 그 결과에 따르면 핑거형 신축이음장치에 수직하중을 인가하였을 경우 핑거에서 측정된 최대 응력은 237.6MPa 이며, 이는 제진 금속의 항복강도인 420MPa의 56.6%이였다. 제진 금속을 이용한 신축이음의 피로시험은 도로교 설계기준에 따라 재하위치(KS F 4425)와 재하판($57.7cm{\times}23.1cm$)의 크기가 설정되었고, 그에 따른 200만회 수직하중 피로 시험에 있어서 파괴거동을 나타내지 않았으며 그 내구성과 안전성을 확인하였다.

문서세단기 성능평가방법의 표준화에 관한 연구 (A Study on Standard of Performance Evaluation for Paper Shredder)

  • 이동규;유송민;이위로;노대호;김민호
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.122-127
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    • 2004
  • The purpose of this study is to introduce the standard of the durability and evaluation method for paper shredder. The major evaluation criteria include shredding capability, shredding blade (or cutter) hardness and edge roughness, and durability. Due to the difficulties in assessing the durability directly, performance deterioration of the shredder was assessed by measuring the torque variation along with the variation in shredded chip size and load, thereby proposing the indirect method of assessing the paper shredder durability.

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고속철도차량용 창문유리의 압력시험에 관한 연구 (A study on the pressure test of the glass window for high speed train)

  • 장대성;이흥재;이원
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.295-300
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    • 2011
  • In this paper, the pressure endurance test of passenger glass window which was developed for next high speed train was studied. At first, pressure test equipment which will be able to generate the maximum pressure same as crossing between two trainsets in the tunnel was developed. Afterwards the pressure test and evaluation that were based on NFF31-314 were studied and carried out.

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재생디젤기관차의 안전성 평가에 관한 연구 (A Study on the Safety Evaluation of Rebuiled Diesel-Electric Locomotive)

  • 이찬우;서정원
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집B
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    • pp.824-829
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    • 2001
  • The main objective of the study is to provide the criteria for determining the proper life cycle of rebuiled diesel-electric locomotive currently being operated in KNR. We predicted the most critical sections of the underframes and tested the diesel-electric locomotive vehicle to measure dynamic stresses applied to the underframes. The fileld test of the diesel-electric locomotive estimated 17.08years based on the fatigue-life estimation when they are continuously used in the present operation condition.

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과학영재아의 인성적 특성에 대한 교사와 부모의 평가에 관한 비교 연구 (A comparative study of evaluation of teachers and parents about the special charateristics of the personality of The Science-Gifted)

  • CHOI, NAM HONG
    • 영재교육연구
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    • 제8권1호
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    • pp.39-64
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    • 1998
  • In order to obtain the special characteristics of the personaliy about the 388 science-gifted in Korean high schools, the evaluaations of their teachers and parents have been analyaed. The results is that notable characteristics are the capacities of concentration, endurance, intelligent curiosity, challenge, reasoning, selr problem-solving, responsibility high level. The evaluations of their teachers and parents are very much correlated, but the evaluations of teachers are superior to those of parents.

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종이의 보존을 위한 이산화황 가스(SO2)의 영향 평가 (Evaluation of the Effects of Sulfur Dioxide(SO2) on Conservation of Paper)

  • 임보아;김명남;이선명
    • 펄프종이기술
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    • 제44권6호
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    • pp.15-20
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    • 2012
  • The effects of sulfur dioxide on paper were investigated since these sulfur compounds could cause damages on cellulose and organic materials in papers. For the reason, exposure ageing tests were performed on traditional Korean paper (Hanji) and two different types of modern paper (acid-free and acid paper) to determine the damage with regard to the optical as well as physicochemical properties according to the varying $SO_2$ concentration. As a result, optical properties were not changed while physical and chemical peoperties were remarkably changed with the exposure period. In the case of pH, $SO_2$ had little impact on the pH of the Hanji and acid-free paper while the pH of acid paper was remarkably decreased. The decrease of the folding endurance of the Hanji was relatively smaller than those of the acid-free and acid paper. The results prove Hanji was more resistant to $SO_2$ than the modern paper in terms of optical, physical and chemical properties. In addition, it was also suggested that $SO_2$ concentration should be kept below 0.01 ppm for the preservation of paper objects.