• 제목/요약/키워드: Normal tension

검색결과 356건 처리시간 0.025초

성상신경절 차단후 발생한 동맥류성 지주막하출혈 -증례 보고- (The Aneurysmal Subarachnoid Hemorrhage following Stellate Ganglion Block -A case report-)

  • 최인주;장원영;윤소영;김경배
    • The Korean Journal of Pain
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    • 제10권1호
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    • pp.121-123
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    • 1997
  • Stellate ganglion block(SGB) is frequently performed to relieve a patient from headache of various. We experienced a rare case of subarachnoid hemorrhage by aneurysmal rupture after SGB. A 46-year-old female patient diagnosed with tension headache, and normal MRI finding consulted our pain clinic. We performed right SGB in combination with greater occipital nerve block. The next day, we performed left SGB with 6 ml of 0.25% bupivacaine. She had no evidence of subarachnoid block or intravascular injection. 15 minutes after injection, she abruptly developed convulsion and loss of consciousness. She was given artificial respiration with oxygen. The diagnosis of ruptured left posterior communicating aneurysm was confirmed by 4-vessels angiography.

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Strength and durability studies on high strength concrete using ceramic waste powder

  • Karthikeyan, B.;Dhinakaran, G.
    • Structural Engineering and Mechanics
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    • 제61권2호
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    • pp.171-181
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    • 2017
  • This paper summarizes the study on effect of ceramic waste powder as partial substitute to cement in binary blend and along with silica fume in ternary blend high strength concrete in normal and aggressive environments. Strength parameters such as compression & tension and durability indices such as corrosion measurement, deterioration, water absorption and porosity were studied. Ceramic waste powder was used in three different percentages namely 5, 10 and 15 with constant percentage of silica fume (1%) as substitutes to cement in ternary blend high strength concrete was investigated. After a detailed investigation, it was understood that concrete with 15% ceramic waste powder registered maximum performance. Increase of ceramic waste powder offered better resistance to deterioration of concrete.

교정력에 의한 치아이동시 백서 치주조직의 대사성 변형에 관한 연구 (A STUDY ON THE METABOLIC ALTERATION OF PERIODONTAL TISSUE ON ORTHODONTIC TOOTH MOVEMENT IN RATS)

  • 장영일
    • 대한치과교정학회지
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    • 제11권2호
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    • pp.65-70
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    • 1981
  • In the present study orthodontic force was applied to the molars of control group and experimental group treated with the lathyrogen beta-aminopropionitrile (BAPN). Observation resulted in the following conclusions : 1) New alveolar bone formation in response to orthodontic force in BAPN-treated rats exceeded corresponding bone formation in control of cup when measured at two tension sites in the periodontal ligament. 2) BAPN administration produced disorganization of the collagenous fibers of the periodontium of experimental group. Multiple eosinophilic cell-free areas were found distributed throughout the radicular portions of affected periodontal ligaments. 3) The areas of periodontium surrounding orthodontically treated teeth exhibited relatively normal organization under these conditions, while the periodontium of adjacent nonorthodontically treated teeth was disorganized. 4) The present results suggest that the typical histologic response to orthodontic force application can occur in the presence of a chemically and physically altered periodontium.

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콘크리트의 방향적 비국소 균열 손상을 위한 소성모델 (Plasticity Model for Directional Nonlocal Crack Damage of Concrete)

  • 김재요;박홍근
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.914-921
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    • 2006
  • To describe the effect of the numerous and various oriented microcracks on the compressive and tensile concrete behaviors, the directional nonlocality is defined. The plasticity model using multiple failure criteria is developed for RC planar members in tension-compression. The crack damages are defined in the pre-determined reference orientations, and then the total crack damage is calculated by integrating multi-oriented crack damages. To describe the effect of directional nonlocality on the anisotropic tensile damage, based on the existing test results, the nonlocal damage factor is defined in each reference orientation. The reduced compressive strength in the cracked concrete is defined by the multi-oriented crack damages defined as excluding the tensile normal plastic strain from the compressive equivalent plastic strain. The proposed model is implemented to finite element analysis, and it is verified by comparisons with various existing panel test results.

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무도상 판형교 레일 장대화에 따른 궤도 유지관리 비교연구 (A comparison study for the track maintenance system for the non-ballast steel plate bridge)

  • 남보현;장태철;우용근;민경주
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.401-410
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    • 2007
  • Form the application of long rail system the non-ballast steel plate bridges, fatigue strength increase and rail noise reduction can be expected. This is mainly form the reduction of the rail impact at the rail joint locations which already made to behave together from welds. In the high speed rail, application of long rail system is essential because without long rail system, the required serviceability level can not be achieved. But even with this long rail systems, the thermal expansion from the girder can not be absorbed in the normal bearing systems, and these expansion cause between girder and rail. Also unexpected rail buckling and fracture through rail thermal tension may happen. It was found through numerical analysis and field measurement that these problems can be avoided by semi-fixed bearing system. In this study, the benefits of non-ballast plate bridge through long rail system, especially at the point of girder stability, girder stiffness increase and bearing maintenance will be reviewed.

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인발법을 포함한 비파괴시험법에 대한 특성 비교 (A Study on the Characteristics of Nondestuctive Tests Including Pullout Test)

  • 고훈범;정성원;음성우
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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    • pp.211-215
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    • 1996
  • This paper presents comparisons of pullout load of concrete with compressive strength of cylinders and cores, pulse velocity, and rebound number. A pullout test, which is a relatively new nondestructive technique, measures with a special tension ram the force required to pullout a specially shaped steel rod whose enlarged end has been cast into a concrete block. In this study 3 concrete mixes(normal strength, high-strength & super-high-strength) were made. From each mix, one 100$\times$70$\times$20 concrete block, 24 cylinders$(\phi10mm)$were casted. Each tests were performed on the concrete blocks at 3, 7, 28, and 91days. The test data shows that the pullout test is superior to the rebond hammer and the pulse velocity measurements on the evaluation of concrete strength. The pullout test is satisfactory for estimating the strength of in situ concrete at both early and late age, and its results can be reproduced with an acceptable degree of accuracy.

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Characteristics of Pressure Confined Concrete under Monotonic Compression

  • Rhim, Hong-Chul;Buyukozturk, Oral;Soon, K. A;Kim, Gwang-Ho
    • KCI Concrete Journal
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    • 제13권1호
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    • pp.53-60
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    • 2001
  • Tests of cylindrical concrete specimens under lateral confining pressure of up to 5,000 psi were conducted for two different axial loading cases: monotonic compression and monotonic tension. The purpose of this experimental investigation is to provide stress-strain characteristics of plain concrete in triaxial stress conditions. Lateral confining pressure levels, loading rates, and strength of concrete specimens are varied as parameters. The loading rates are $34.75$\times$10^{-5}$ in/in/sec for fast, $\times$$6.95x10^{-5}$ in/in/sec for normal. and $0.579$\times$10^{-5}$ in/in/sec for slow loading cases. The concrete specimens used in the experiment have compressive strength of 3,500 psi and 6,500 psi, respectively. Findings of this experiment include dependency of the stress-strain behavior of concrete on the above parameters under two different types of loading conditions. The parametric study includes a series of 106 triaxial tests.

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Flexural ductility of RC beam sections at high strain rates

  • Pandey, Akhilesh K.
    • Computers and Concrete
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    • 제12권4호
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    • pp.537-552
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    • 2013
  • Computation of flexural ductility of reinforced concrete beam sections has been proposed by taking into account strain rate sensitive constitutive behavior of concrete and steel, confinement of core concrete and degradation of cover concrete during load reversal under earthquake loading. The estimate of flexural ductility of reinforced concrete rectangular sections has been made for a wide range of tension and compression steel ratios for confined and unconfined concrete at a strain rate varying from $3.3{\times}10^{-5}$ to 1.0/sec encountered during normal and earthquake loading. The parametric studies indicated that flexural ductility factor decreases at increasing strain rates. Percentage decrease is more for a richer mix concrete with the similar reinforcement. The confinement effect has marked influence on flexural ductility and increase in ductility is more than twice for confined concrete (0.6 percent volumetric ratio of transverse steel) compared to unconfined concrete. The provisions in various codes for achieving ductility in moment resisting frames have been discussed.

임상간호사가 지각한 간호사 자아상: Q 방법론적 접근 (Nurses' Self-Image Perceived by Clinical Nurses: An Application of Q-Methodology)

  • 하은호;현경순
    • 성인간호학회지
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    • 제26권1호
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    • pp.117-128
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    • 2014
  • Purpose: The views, perceptions, and feelings of nurses themselves would be important to quality of nursing and professionalism, and turnover intentions. The purpose of this study was to identify nurses 'self-image to develop a customized program. Methods: The Q-methodology which is to create a typology was used. The 40 selected Q-statements from each of 35 participants were classified into a shape of normal distribution using a nine point scale. The collected data were analyzed using a PC-QUANL program. Results: Three types of nurses 'self-image were identified: 'proactive self-image', 'critical self-image', and 'adaptive self-image'. Two consensus items in three types were extracted: 'need to develop healing therapies to overcome the constant tension and exhaustion from work', and 'just think as a colleague than the senior-junior relationship. Conclusion: The results is the typology and this leads to further research.

장척레일 축력 비교 연구 (A comparison study for the Axial forte of Longer Rail)

  • 민경주;이성욱;박대희
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.516-528
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    • 2009
  • Form the application of long rail system the non-ballast steel plate bridges, fatigue strength increase and rail noise reduction can be expected. This is mainly form the reduction of the rail impact at the rail joint locations which already made to behave together from welds. In the high speed rail, application of long rail system is essential because without long rail system, the required serviceability level can not be achieved. But even with this long rail systems, the thermal expansion from the girder can not be absorbed in the normal bearing systems, and these expansion cause between girder and rail. Also unexpected rail buckling and fracture through rail thermal tension may happen. It was found through numerical analysis and field measurement that these problems can be avoided by semi-fixed bearing system. In this study, the benefits of non-ballast plate bridge through long rail system, especially at the point of girder stability, girder stiffness increase and bearing maintenance will be reviewed.

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