• 제목/요약/키워드: Dead weight

검색결과 288건 처리시간 0.052초

Screening of Alstonia scholaris Linn. R. Br., for wound healing activity

  • S, Arulmozhi;VP, Rasal;Sathiyanarayanan, L;Ashok, Purnima
    • Advances in Traditional Medicine
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    • 제7권3호
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    • pp.254-260
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    • 2007
  • Alstonia scholaris (Family: Apocynaceae) has been indicated for the treatment of various diseases, one among which is wound healing. The purpose of this study is to investigate the wound healing effect and antioxidant role of Alstonia scholaris leaves in animal models. The ethanol and aqueous extracts of Alstonia scholaris (EEAS, AEAS respectively) were tested against excision, incision and dead space wound models to evaluate the wound healing activity. In excision wound model, treatment was continued till the complete healing of wound, in incision and dead space wound models, the treatment was continued for 10 days. For topical application, 5% w/w ointment of EEAS and AEAS were prepared in 2% sodium alginate. For oral administration, EEAS was suspended in distilled water using Tween 80 and AEAS was dissolved in distilled water. The wound healing was assessed by the rate of wound contraction, period of epithelialisation, skin breaking strength, granulation strength, dry granulation tissue weight, hydroxyproline, collagen and histopathology of granulation tissue. Malondialdehyde level was also estimated to evaluate the extent of lipid peroxidation. AEAS and EEAS significantly promoted wound healing activity in all the wound models studied. Increase in the rate of wound contraction, skin breaking strength, granulation strength, dry granulation tissue weight, hydroxyproline and collagen, decrease in the period for epithelialisation and increased collagenation in histopathological section were observed with EEAS and AEAS treated groups. EEAS and AEAS also significantly decreased the levels of lipid peroxidation. The present study is suggestive that EEAS and AEAS promote wound healing activity.

KSTAR 초전도자석 지지각 시작품재작 및 구조시험 (KSTAR Superconducting Magnet Supporting Post Prototype Manufacturing and Structural Load Test)

  • 허남일;이영신
    • 한국초전도ㆍ저온공학회논문지
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    • 제3권1호
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    • pp.45-49
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    • 2001
  • A magnet supporting post installed between the lower TF coil tooled by 4.5 K supercritical helium and the cryostat base is one of the most important components of the superconducting magnet supporting structure for KSTAR Tokamak. This structure should be flexible to absorb thermal shrink of the magnet and also should be rigid to support the magnet weight and the Plasma disruptions load. The Post was designed with stainless steel 316LN and CFRP that have low thermal conductivity and high structural strength at low temperature. In order to verify the possibility of fabrication and the structural safety. a whole scale prototype of the KSTAR magnet supporting post was manufactured and tested. Static and compressive cyclic load tests under the maximum Plasma vertical disruption load and the magnet dead weight were performed. The teat results showed that the magnet supporting post of KSTAR Tokamak was possible to manufacture and structurally rigid.

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고강도-경량콘크리트의 실용화를 위한 기초적 실험 연구 (Fundamental Tests of High Strength Lightweight Concrete for Application)

  • 이재삼;김정식;강훈;최명신;안종문;신성우
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.393-400
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    • 1997
  • It is possible to reduce dead load and cross section of structural members by use of lightweight concrete, and also reduce the cost of construction. The mechanical properties of lightweight concrete are lower than that of normal weight concrete having the same compressive strength, then it is necessary to make higher strength of lightweight concrete for structural use, and the objective of this paper is to development and application the highstrength lightweight concrete with lower than 2.0t/$\textrm{m}^3$ of unit weight and over than 350kg/$\textrm{cm}^2$ of compressive strength.

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케이블 횡진동을 고려한 3차원 사장교의 동적거동 (Dynamic Response of 3-D Cable-Stayed Bridge Considering the Sway Vibrational Effect of Stays)

  • 성익현
    • 한국철도학회논문집
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    • 제2권3호
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    • pp.36-45
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    • 1999
  • The basic idea of cable-stayed girder bridges is the utilization of high strength cables to provide intermediate supports for the bridge girder so that the girder can span a much longer distance. In the cable-stayed bridge, the cables exhibit nonlinear behavior because of the change in sag, due to the dead weight of the cable, which occurs with changing tension in the cable resulting from the movement of the end points of the cable as the bridge is loaded. Techniques required for the static analysis of cable-stayed bridges has been developed by many researchers. However, little work has been done on the dynamic analysis of such structures. To investigate the characteristics of the dynamic response of long-span cable-stayed bridges due to various dynamic loadings likes moving traffic loads. two different 3-D cable-stayed bridge models are considered in this study. Two models are exactly the same in structural configurations but different in finite element discretization. Modal analysis is conducted using the deformed dead-load tangent stiffness matrix. A new concept was presented by using divided a cable into several elements in order to study the effect of the cable vibration (both in-plane and swinging) on the overall bridge dynamics. The result of this study demonstrates the importance of cable vibration on the overall bridge dynamics.

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트랙터 작업기의 경심 자동제어시스템 (Automatic Depth Control System for Tractor Implement)

  • 최창현;나경환;김재민
    • Journal of Biosystems Engineering
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    • 제18권4호
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    • pp.328-343
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    • 1993
  • To control depth of tractor implement, an automatic depth control system based upon microcomputer was developed. This system consists of data aquisition system to measure and to record travel speed, draft and depth of the implement, hydraulic system to control the implement depth and 3-point hitch to attach the implement. Program, written in C language, was able to select position control, draft control and mixed control. To analyze parameters affecting this system, the performance of the system was evaluated through use of computer simulation and verified in soil bin experiments. 3-point hitch was lifted by hydraulic pressure and lowered by implement weight. Dead band was one of the important factors which affect the stability and the accuracy of the system. The system became unstable when the flow rate was increased or when the dead band was decreased. The position control mode with on-off control showed the great ability to control the implement at the given plowing depth. With the draft control, the tractor load could be reduced, however the plowing depth was changed unexpectedly when the soil was hard and inconsistent. The mixed control could improve the performance of the system to maintain the plowing depth without overload of the tractor.

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Embryonic Growth, Hatching Time and Hatchability Performance of Meat Breeder Eggs Incubated under Continuous Green Light

  • Shafey, T.M.;Al-mohsen, T.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권12호
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    • pp.1702-1707
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    • 2002
  • The effects of dark-control (D) and continuous green light (GL) exposure of incubated meat-type breeder eggs (Hybro) on embryonic growth from 5 to 15 days of age, hatching time, hatchability per cent and chick hatching weight were investigated in three consecutive experiments at 33, 38, and 41 weeks of age. A total of 798 eggs were used in this study. Eggs were set in an incubator on trays either in the D or under two tubes of 20-watt green fluorescent light during the first 18 days of incubation. Eggs from both treatments were transferred to the dark hatching compartment at 19 days of incubation. The light intensity was in the range of 1,340 to 1,730 lux at the surface of the eggs. GL incubation of eggs significantly (p<0.01) increased weight (expressed as an absolute value) and daily weight gain of embryos at 11 and continued to 15 days of age, hatchability per cent by 4.8%, reduced dead embryos per cent and chick weight at hatch by 37 and 2%, respectively and accelerated hatching time by about 24 h when compared with the D-control incubation. Chicks hatched at 504 h of incubation had significantly (p<0.01) higher body weight, expressed as an absolute value or as a percentage of egg weight, than those hatched earlier at 456 h of incubation. It was concluded that the GL incubation of meat breeder eggs reduced incubation period and chick weight at hatch and increased embryonic growth and hatchability per cent.

Behavior of one way reinforced concrete slabs with styropor blocks

  • Al-Azzawi, Adel A.;Abbas, J;Al-Asdi, Al-Asdi
    • Advances in concrete construction
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    • 제5권5호
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    • pp.451-468
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    • 2017
  • The problem of reducing the self-weight of reinforced concrete structures is very important issue. There are two approaches which may be used to reduced member weight. The first is tackled through reducing the cross sectional area by using voids and the second through using light weight materials. Reducing the weight of slabs is very important as it constitutes the effective portion of dead loads in the structural building. Eleven slab specimens was casted in this research. The slabs are made one way though using two simple supports. The tested specimens comprised three reference solid slabs and eight styropor block slabs having (23% and 29%) reduction in weight. The voids in slabs were made using styropor at the ineffective concrete zones in resisting the tensile stresses. All slab specimens have the dimensions ($1100{\times}600{\times}120mm$) except one solid specimens has depth 85 mm (to give reduction in weight of 29% which is equal to the styropor block slab reduction). Two loading positions or cases (A and B) (as two-line monotonic loads) with shear span to effective depth ratio of (a/d=3, 2) respectively, were used to trace the structural behavior of styropor block slab. The best results are obtained for styropor block slab strengthened by minimum shear reinforcement with weight reduction of (29%). The increase in the strength capacity was (8.6% and 5.7%) compared to the solid slabs under loading cases A and B respectively. Despite the appearance of cracks in styropor block slab with loads lesser than those in the solid slab, the development and width of cracks in styropor block slab is significantly restricted as a result of presence a mesh of reinforcement in upper concrete portion.

멸종위기종 수리부엉이의 형태학적 및 혈액학적 분석 (Morphological and hematological analysis of and angered Eurasian eagle owl (Bubo bubo kiautschensis))

  • 정배동;박인철;김정남;김현철;정기수;김종택
    • 한국동물위생학회지
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    • 제32권4호
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    • pp.391-397
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    • 2009
  • Eurasian eagle owl (Bubo bubo kiautschensis) is a natural monument (No. 324) and is also classified as an endangered wildlife grade II the Ministry of Environment of Korea. Eurasian eagle owl is threatened by the human being. But the efficient rescue and treatment for Eurasian eagle owl are still problematic, due to lack of basic data. In this study, to obtain basic resources for establishing more efficient rescue system, we held a physical examination and measured size physical part. In addition, we analyzed blood sample and feces samples and autopsy. We conduct the physical examination with measuring tapes and scales for 16 live features and 11 dead features. After inhalation anesthesia take the blood samples from wing vein. Blood samples are analyzed in hematologic and chemistric methods. We collected the feces through individual floor of cages from 12 live features and conducted the feces analysis. Autopsy was conducted for 11 dead samples. In physical examination, the mean body weight and total length of live features was 2.26${\pm}$0.35kg, 61${\pm}$2.38cm, the mean body weight and total length of dead features was 1.57${\pm}$0.51kg, 59.31${\pm}$3.51cm. Mean PCV was 46.57${\pm}$4.97%, while mean TPP was 3.49${\pm}$0.57g/dL. In feces sample analysis, 9 of 12 owls(75%) were infested by gastrointestinal helminths. The infection rates were: Trematoda (41.7%), Capilaria sp.(66.7%), acanthocephalans (25%). In autopsy, we confirmed 11 features were infested by duplicated infection of more than 2 helminths. Result of this study will be used for establishing reference range for physical features, blood analysis in Eurasian eagle owl. Therefore, to obtain basic resources for establishing more efficient rescue system, we have to make long-term conservation plans for Eurasian eagle owl.

치과 보철용 금속 합금의 마찰 마멸 특성 (Tribological Characteristics of Dental Metal Alloys)

  • 김종훈;최원식
    • Tribology and Lubricants
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    • 제29권4호
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    • pp.235-241
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    • 2013
  • The tribological characteristics of dental metal alloys and zirconia were studied by carrying out a friction and wear performance test. In this study, a pin-on-disk-type tester was used and dead weight was employed as the normal load applied to the test specimen. The friction coefficient of dental metal alloys was investigated in terms of their weight and sliding velocity. Microscopic observations were carried out on worn surfaces of specimens. The results indicated that among all metal alloys, Super-A had the highest friction coefficient. Super-A had the lowest amount of wear among all metal alloys, and the amount of wear increased in the following order: Crown & Bridge, Porcelain, and Partial. Crown & Bridge had the best friction coefficient, but the hardness of Crown & Bridge was lower than that of Porcelain and Partial. Experimental measurement results indicated that the disk weight before and after the experiment was the same.

Effects of Low intensity Cardiac Rehabilitation Exercise on Weight and Histological Changes of Rat Models with Acute Myocardial Infarction

  • Ji, Sung Ha;Kim, Ki Jong
    • 국제물리치료학회지
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    • 제7권1호
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    • pp.949-955
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    • 2016
  • The purpose of the study was to investigate effects of Low intensity cardiac rehabilitation, using a treadmill, on the myocardial structure. We identified the effects by analyzing changes in the rats' weights and the results of biopsies. Twenty Sprague-Dawley male rats, 50 weeks old, were randomly divided into the exercise group and the control group. myocardial infarction(MI) was induced by ligaturing their left anterior descending artery. After the acute MI induction, two rats of each group began to fall dead, therefore, eight of each group completed at the end of the experiment. We used treadmills for animals for the exercise group. This exercise group performed 30 minutes of exercise five times per week for six weeks, while the control group did not perform any exercise. No statistically significant differences in weight were found in within group comparison and between group comparison. Furthermore, we observed histological changes in the myocardium using Hematoxylin & Eosin and Masson's trichrome staining in both groups. Low-intensity exercise inhibited myocardial fibrosis, may serve as a reference in the cardiopulmonary field, which plays a role in rehabilitating patients with cardiac disorders, including acute MI.