• 제목/요약/키워드: Skin Resistance

검색결과 406건 처리시간 0.024초

Behavior of concrete-filled double skin steel tube beam-columns

  • Hassan, Maha M.;Mahmoud, Ahmed A.;Serror, Mohammed H.
    • Steel and Composite Structures
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    • 제22권5호
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    • pp.1141-1162
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    • 2016
  • Concrete-filled double skin steel tube (CFDST) beam-columns are widely used in industrial plants, subways, high-rise buildings and arch bridges. The CFDST columns have the same advantages as traditional CFT members. Moreover, they have lighter weight, higher bending stiffness, better cyclic performance, and have higher fire resistance capacities than their CFT counterparts. The scope of this study is to develop finite element models that can predict accepted capacities of double skin concrete-filled tube columns under the combined effect of axial and bending actions. The analysis results were studied to determine the distribution of stresses among the different components and the effect of the concrete core on the outer and inner steel tube. The developed models are first verified against the available experimental data. Accordingly, an extensive parametric study was performed considering different key factors including load eccentricity, slenderness ratio, concrete compressive strength, and steel tube yield strength. The results of the performed parametric study are intended to supplement the experimental research and examine the accuracy of the available design formulas.

Clonidine Patch에 피부자극성 시험 (Skin Irritation Test of Clonidine Patch)

  • 이영순;박우일;고광호
    • Biomolecules & Therapeutics
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    • 제4권2호
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    • pp.202-204
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    • 1996
  • Clonidine, an antihypertensive drug, stimulates postsynaptic $\alpha_2$adrenergic receptors in the CNS and lowers arterial pressure by erects on both cardiac output and peripheral resistance. However, many patients experience that sedation and xerostomia occured upon oral administration of clonidine. These side effects are due to high plasma peak concentration and can be avoided when clonidine is given transdermally. In this study, we performed the skin irritation test for transdermal administration of clonidine patch on New Zealand white rabbits. Twelve New Zealand white rabbits were divided into two groups according to the dose levels, respectively. After transdermal administration of clonidine patch with two doses, clinical manifestations, body weight loss and postmortem findings were observed. We could not find any significant evidence of skin irritation by transdermal administration of clonidine patch.

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버팀재 볼트 접합형 강재스트립 보강재의 인발거동특성 평가 (An Evaluation of Pullout Behavior Characteristics of the Steel Strip Reinforcement Bolted with Braced Angles)

  • 김홍택;방윤경;정중섭;박시삼;김현조
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.419-426
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    • 2002
  • In this study, the steel strip reinforcement bolted with braced angles is displayed skin friction resistance as well as passive resistance through existing the steel strip reinforcement. To understand pullout behavior characteristics, friction effects between soil and reinforcement are evaluated with the width of reinforcement, magnitude of surcharge, and existence of passive resistance member through laboratory pullout test. To analyze interference effects for passive resistance member, various tests are carried on case that the number, the location, and the spacing of braced angles are different. Using this test result, pullout resistance factor is calculated to consider location of braced angles and degree of interference for spacing ratio.

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상사축척법에 기반한 저마찰 선박 방오도료의 실선 마찰저항 저감성능 추정 (Full Scale Frictional Resistance Reduction Effect of a Low Frictional Marine Anti-fouling Paint based on a Similarity Scaling Method)

  • 양정우;박현;이인원
    • 대한조선학회논문집
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    • 제54권1호
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    • pp.71-81
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    • 2017
  • In this study, a series of full-scale extrapolation procedures based on the Granville's similarity scaling method, which was employed by Schultz (2007), is modified and then applied to compare the resistance performance between two different anti-fouling coatings. As an analysis example, the low frictional AF coating based on a novel skin-friction reducing polymer named FDR-SPC (Frictional Drag Reduction Self-Polishing Copolymer), which had been invented by the present author, is employed. The low frictional coating, which gives 25.4% skin frictional reduction in lab test, is estimated to give 18.2% total resistance reduction for a 176k DWT bulk carrier.

하중 방향(압축-인발)과 말뚝 직경이 말뚝의 지지력에 미치는 영향에 관한 연구 -실내모형시험- (The Effect of Load Direction and Pile Size on the Pile Bearing Capacity : Model Pile Tests)

  • 이인모;백세환
    • 한국지반공학회지:지반
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    • 제8권3호
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    • pp.13-22
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    • 1992
  • Model pile tests using calibration chamber are performed in !his paper in order to clarify the effect of the fundamental differences between the newly developed SPLT(Simple Pile Loading Test)and the conventional pile loading test on the pile bearing capacity. They are : (1) the direction of the applied load to mobilize the skin friction ; and (2) the use of reduced sifted sliding core. The conclusions obtained from the model pile tests are as follows : (1) The skin friction in tension loading is found to be somewhat smaller than that in compression loading. The average ration is 0.73 with the coefficient of variation (COV) of 0.18. (2) The ratio of the tip resistance rosin연 the reduced sized sliding core to that using the whole shoe shows wide scattering ; its average is 0.99 and the COV is 0.28. The aver - age of 0.99 means that there is no considerable difference in the tip resistance whether the reduced sized sliding core or the whole shoe is used, on condition that penetration depth ratio is larger than 4 : if the boundary effect of the chamber test is considered, the resistance of the whole shoe might be even larger.

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풍화잔류토 지반에 타설된 말뚝의 주면마찰 특성 연구 (A Study on the Skin Friction of Piles Driven into Residual Soils)

  • 이명환;이인모
    • 한국지반공학회지:지반
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    • 제8권2호
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    • pp.21-30
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    • 1992
  • 말뚝의 주면마찰력은 전체 지지력중 상당한 하중을 지지할 수 있으나 실제 설계시에는 무시되는 경우가 많이 있다. 주면마찰력을 설계에 반영할 경우에도 계산결과의 신뢰도는 매우 낮은 것이 현실이다. 국내의 사정은, 설계 자료로 활용할 수 있는 것은 표준관입시험 결과뿐인 경우가 대부분으로 빈곤하며 특히 국내에 많은 화강암, 편마암의 풍화잔류토에 관해서는 설계자료가 극히 희박해 외국에 비해 열악하다. 최근에 국내에서 개발된 간편한 말뚝재하시험(simple pile loading test: SPLT)의 사용은 선단지지력과 주면마찰력의 별도 측정이 가능하도록 하였다. 본 연구에서는 풍화잔류토 지반에서의 SPLT 결과를 분석하여 N값에 의한 새로운 설계관계식을 제안하였다.

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세포교정영양요법(OCNT)를 이용한 흑색 극세포증 환자 사례 연구 (A Case Study on Patients with Acanthosis Nigricans Receiving Ortho-Cellular Nutrition Therapy (OCNT))

  • 김숙현
    • 셀메드
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    • 제13권5호
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    • pp.18.1-18.3
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    • 2023
  • Objective: A case report on the improvement of patients with acanthosis nigricans by Ortho-Cellular Nutrition Therapy (OCNT). Methods: A 23-year-old Korean male who has begun to have the symptoms of acanthosis nigricans two years ago has been experiencing more severe symptoms in the past year. Results: Skin pigmentation and lichenification symptoms improved after Ortho-Cellular Nutrition Therapy (OCNT). Conclusion: Ortho-Cellular Nutrition Therapy (OCNT) is effective in relieving the symptoms of patients with acanthosis nigricans.

Evaluation of AC Resistance in Litz Wire Planar Spiral Coils for Wireless Power Transfer

  • Wang, Xiaona;Sun, Pan;Deng, Qijun;Wang, Wengbin
    • Journal of Power Electronics
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    • 제18권4호
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    • pp.1268-1277
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    • 2018
  • A relatively high operating frequency is required for efficient wireless power transfer (WPT). However, the alternating current (AC) resistance of coils increases sharply with operating frequency, which possibly degrades overall efficiency. Hence, the evaluation of coil AC resistance is critical in selecting operating frequency to achieve good efficiency. For a Litz wire coil, AC resistance is attributed to the magnetic field, which leads to the skin effect, the proximity effect, and the corresponding conductive resistance and inductive resistance in the coil. A numerical calculation method based on the Biot-Savart law is proposed to calculate magnetic field strength over strands in Litz wire planar spiral coils to evaluate their AC resistance. An optimized frequency can be found to achieve the maximum efficiency of a WPT system based on the predicted resistance. Sample coils are manufactured to verify the resistance analysis method. A prototype WPT system is set up to conduct the experiments. The experiments show that the proposed method can accurately predict the AC resistance of Litz wire planar spiral coils and the optimized operating frequency for maximum efficiency.

월경통 치료 전과 후의 적외선체열영상 및 피부저항변이도 변화에 대한 연구 (A Study on the Change of Digital Infrared Thermographic Imaging and Skin Resistance Variability before and after Treatment of Dysmenorrhea)

  • 김현주;이용현;손영주
    • 대한한방부인과학회지
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    • 제26권2호
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    • pp.88-103
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    • 2013
  • Purpose: The aim of this study was to examine the effect of oriental diagnosis and treatment for dysmenorrhea patients on lower abdominal temperature and Skin Resistance Variability(SRV). Methods: We studied twenty-five dysmenorrhea patients, who visited Oriental Medicine Hospital of ${\bigcirc}{\bigcirc}$ University for 10 months(Sep. 2011~Jun. 2012). Patients with organic disease such as endometriosis, uterine myoma and pelvic inflammatory disease were excluded from this study. We prescribed 3 types of treatments, herbal medicine, acupuncture, and moxibustion, for one menstrual cycle. Digital Infrared Thermographic Imaging(DITI), 7-Zone-Diagnostic System(CP-6000A), VAS(Visual analog scale) and MVRS(Multidimensional verbal rating scale) were conducted before and after the treatment. The result of DITI, 7-Zone-Diagnostic System, VAS and MVRS before and after treatment were compared in order to objectively assess the therapeutic effect. Results: When we compared the results of DITI, CV4 temperature after treatment was increased compared with that of before, and temperature difference between CV12 and CV4 after treatment was decreased compared with that of before. But there was no significant difference. When we compared the results of 7-Zone-Diagnostic System at 1st and 2nd trial, the height of 1~5 area was lower than that of before. And at 1st and 2nd trial, the height of 6, 7 area was higher than that of before, but there were no significant difference in most. When we compared the results of VAS and MVRS, VAS and MVRS after treatment was significantly decreased compared with that of before(p<0.01). Conclusions: This study shows that oriental diagnosis and treatment for dysmenorrhea patients affects the results of DITI. Further study will be needed.

부인과내원환자의 피부저항변이도 패턴에 관한 연구 (A study on Skin Resistance Variability(SRV) of reproductive women who visited Gynecologic Clinic)

  • 안지선;박찬수;정민영;손영주
    • 대한한방부인과학회지
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    • 제19권3호
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    • pp.191-201
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    • 2006
  • Purpose : Skin Resistance Variability(SRV) is a kind of biofunctional signal, and it can show the function of autonomic nervous system, especially in the sympathetic nerve. The objective of this study is to find out the differences of SRV of reproductive women with aging. Method : We measured SRV(by CP-6000A) of 151 women who visited Gynecologic Clinic. And the results were classified according to age, by five groups. After detection of SRV, we performed correlation analysis and ANOVA by SPSS 12.0. Results : 1. The SRV was measured twice. It resulted in seven areas. In 1, 2, 3 areas, the second results were higher than first results in every groups. In 4, 5, 6, 7 areas, the first results were higher than second results in every groups. 2. The SRV of lower part (4, 5, 6, 7 area) on the body was higher than that of higher part (1, 2, 3 area). 3. The SRV in the youngest group was higher than the oldest group in 1, 2, 3 area of second trial. Conclusion : With relations to the standardization and objectification of oriental medicine, we expect that these results contribute to gynecologic clinic in the department of diagnosis of functional abnormality of hypothalamus-hypophysis-ovarian axis (H-P-O axis).

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