• 제목/요약/키워드: Connecting fibers

검색결과 23건 처리시간 0.025초

Variant muscle fibers connecting the orbicularis oculi to the orbicularis oris: case report

  • Norio Kitagawa;Joe Iwanaga;R.Shane Tubbs;Hongtae Kim;Yong-Suk Moon;Mi-Sun Hur
    • Anatomy and Cell Biology
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    • 제55권4호
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    • pp.497-500
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    • 2022
  • The orbicularis oculi (OOc) is a sphincteric muscle of the eyelids, whereas contraction of the orbicularis oris (OOr), another sphincteric muscle, causes narrowing of the lips. Facial muscle fibers normally blend with adjacent muscles. However, muscle fibers connecting the various facial muscles that have different actions and that are located at distant sites, such as the OOc and the OOr have been rarely reported. Herein, we report a rare case of connecting fibers between the inferior margin of the OOc and the OOr. These connecting fibers were blended with the OOr between the inserting fibers of the levator labii superioris and levator anguli oris. Contraction of such variant muscles might affect typical facial expressions.

Finite element analysis of shear critical prestressed SFRC beams

  • Thomas, Job;Ramaswamy, Ananth
    • Computers and Concrete
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    • 제3권1호
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    • pp.65-77
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    • 2006
  • This study reports the details of the finite element analysis of eleven shear critical partially prestressed concrete T-beams having steel fibers over partial or full depth. Prestressed concrete T-beams having a shear span to depth ratio of 2.65 and 1.59 and failing in the shear have been analyzed using 'ANSYS'. The 'ANSYS' model accounts for the nonlinear phenomenon, such as, bond-slip of longitudinal reinforcements, post-cracking tensile stiffness of the concrete, stress transfer across the cracked blocks of the concrete and load sustenance through the bridging of steel fibers at crack interface. The concrete is modeled using 'SOLID65'-eight-node brick element, which is capable of simulating the cracking and crushing behavior of brittle materials. The reinforcements such as deformed bars, prestressing wires and steel fibers have been modeled discretely using 'LINK8' - 3D spar element. The slip between the reinforcement (rebar, fibers) and the concrete has been modeled using a 'COMBIN39'-non-linear spring element connecting the nodes of the 'LINK8' element representing the reinforcement and nodes of the 'SOLID65' elements representing the concrete. The 'ANSYS' model correctly predicted the diagonal tension failure and shear compression failure of prestressed concrete beams observed in the experiment. The capability of the model to capture the critical crack regions, loads and deflections for various types of shear failures in prestressed concrete beam has been illustrated.

Prediction of the Rupture of Circular Sections of Reinforced Concrete and Fiber Reinforced Concrete

  • Adjrad, A.;Bouafia, Y.;Kachi, M.S.;Ghazi, F.
    • International Journal of Concrete Structures and Materials
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    • 제10권3호
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    • pp.373-381
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    • 2016
  • As part of this study, has been developed a numerical method which allows to establish abacuses connecting the normal force with bending moment for a circular section and therefore to predict the rupture of this type of section. This may be for reinforced concrete (traditional steel) or concrete reinforced with steel fibers. The numerical simulation was performed in nonlinear elasticity up to exhaustion of the bearing capacity of the section. The rupture modes considered occur by plasticization of the steel or rupture of the concrete (under compressive stresses or tensile stresses). Regarding the fiber-reinforced concrete, the rupture occurs, usually, by tearing of the fibers. The behavior laws of the different materials (concrete and steel) correspond to the real behavior. The influence of several parameters was investigated, namely; diameter of the section, concrete strength, type of steel, percentage of reinforcement and contribution of concrete in tension between two successive cracks of bending. A comparison was made with the behavior of a section considering the conventional diagrams of materials; provided by the BAEL rules. A second comparative study was performed for fibers reinforced section.

단방향 연속 섬유 복합재 횡단면에서 섬유 배열에 따른 응력 분포 변화 (Effects of Fiber Arrangements on Stress Distributions over the Transverse Cross Section of Unidirectionally Continuous Fiber-reinforced Composites)

  • 최수훈;지우석
    • Composites Research
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    • 제33권1호
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    • pp.30-37
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    • 2020
  • 단방향 연속 섬유 강화 복합소재에 대하여 섬유 배열에 따른 응력 분포 양상을 연구하기 위해 단면 형상을 대표하는 체적 요소를 생성하였다. 대표 체적 요소에 횡방향 하중을 가하였을 때, 섬유와 기지재 강성의 차이로 인해 섬유 둘레에서 응력 집중 현상이 발생하며, 섬유 간 좁은 간격 때문에 집중된 응력이 중첩되며 섬유 주변에서 높은 응력이 구해질 것이라 쉽게 예측할 수 있다. 본 연구에서는 섬유 둘레 응력 증감이 단순히 섬유 간 간격 뿐 아니라 섬유의 상대적 위치가 하중 방향과 이루는 각도에 의해서도 결정됨을 보여준다. 정규 육각 구조를 가지는 대표 체적 요소의 중앙에 위치한 섬유를 다양한 방향으로 이동시키며 횡방향 하중을 가하여, 섬유 주변 응력이 증가하거나 감소하는 양상을 유한요소해석 기법을 이용해 측정하였다. 섬유 간 거리가 최소이면서 두 섬유의 중심을 잇는 선분의 방향이 하중 방향과 일치할 때 응력이 최대로 증가하였으며, 섬유 간 거리가 최소라 하더라도 하중 방향에 수직일 때 최대 응력은 오히려 감소한다는 것을 보여준다.

철도 사고현장의 효율적인 동영상 전송 방안에 관한 연구 (A study on effective sending of moving picture from train accident site)

  • 조봉관;장석각
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.289-291
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    • 2003
  • Railway takes an important role of transporting massive passenger and freight. Accidents which occur related to trains have a risk of serious loss of lives, so those accidents need to be controlled urgently Therefore moving picture transmission system is required which transmits exact information of moving picture of accident status to CTC and also communication line is also required with it. By using WTB line as a wayside transmission line, railway telephones, fax and train service information are provided to local offices. As transmission line improving project, optical cabling work is being processed by phases. Therefore optical fiber line is more effective way for a communicating way between stations than coaxial transmission line. This Paper considers connecting method when optical fibers is used for moving picture data transmission of train accidents and its problems.

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남매에서 발생한 가족성 판상부 대동맥협착증 (Familial Surpravalvular Aorctic Stenosis in Two Silings)

  • 강재걸
    • Journal of Chest Surgery
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    • 제21권6호
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    • pp.1145-1151
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    • 1988
  • Supraventricular tachyarrhythmias are readily characterized and understood, but the surgical procedures for their correction are complex and not easily mastered. Conversely, ventricular tachyarrhythmias are frequently difficult to characterize and localize electrophysiologically and their basic mechanisms are poorly understood. The role of the surgeon in the treatment of cardiac arrhythmia has changed dramatically during the past decade. This report is a case of 26 years old male with supraventricular tachyarrhythmia. The result of endocardial electrophysiologic study demonstrated accessory pathway connecting left atrium to left ventricle which located at left atrial free wall about 4 cm apart from the coronary sinus orifice. The accessory bundle interruption has been successfully accomplished utilizing the internal open heart technique. The operation consisted of dissection of the atrioventricular fat pad and division of all the superficial fibers going from the ventricle to the annulus. Following this, cryoablation made with cryoprobe at - 60` for 90 seconds. The accessory pathway was successfully ablated without specific problems.

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광선로를 경유한 철도현장의 영상전송방안에 관한 연구 (A study on the moving picture transmission method by railway fibers optics cable)

  • 장석각;조봉관
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.1465-1467
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    • 2004
  • Compared with other transport means, safety and timeliness are the merits of railways. Unexpectedly when accident happens, much time and human strength are required to cope with the accident. And for swift recovery, systematic rehabilitation is needed. Recently using MTS(Moving picture Transmission System), we can perform accident rehabilitation and recording work efficiently. MTS is the device that transmits continuous picture information from accident field to control center. e are developing the appropriate system to railway situation to make use of the existing information communication technology, processing technology of video-tex, super high speed transmission technology through fiber-optic, copper cable and network description of information Technology, etc. If these communication-based can technologies are applied to railway system, railway managers can control the accident by inspecting the picture of accident field and can contribute to the safe train operation and the improvement of railway management. In this paper, we investigate the connecting methods when optical fiber is used for moving picture data transmission of train accidents, and its problems. And, we validate MTS's performance through about 28km section of field test.

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사고현장과 사령실간 화상전송기술에 관한 연구(III) (A Study on the moving picture transmission method between the accident sites and control center)

  • 조봉관;장석각;최규형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.1412-1414
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    • 2004
  • Railway takes an important role of transporting massive passenger and freight. Accidents which occur related to trains have a risk of serious loss of lives, so those accidents need to be controlled urgently. Therefore moving picture transmission system is required which transmits exact information of moving picture of accident status to CTC and also communication line is also required with it. By using WTB line as a wayside transmission line, railway telephones, fax and train service information are provided to local offices. As transmission line improving project, optical cabling work is being processed by phases. Therefore optical fiber line is more effective way for a communicating way between stations than coaxial transmission line. This paper consider's connecting method when optical fibers is used for moving picture data transmission of train accidents and its problems.

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A Understanding of the Temporal Stem

  • Choi, Chan-Young;Han, Seong-Rok;Yee, Gi-Taek;Lee, Chae-Heuck
    • Journal of Korean Neurosurgical Society
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    • 제47권5호
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    • pp.365-369
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    • 2010
  • Objective : There has been inconsistency about definition of the temporal stem despite of several descriptions demonstrating its microanatomy using fiber dissection and/or diffusion tensor tractography. This study was designed to clarify three dimensional configurations of the temporal stem. Methods : The fronto-temporal regions of several formalin-fixed human cerebral hemispheres were dissected under an operating microscope using the fiber dissection technique. The consecutive coronal cuts of the dissected specimens were made to define the relationships of white matter tracts comprising the temporal stem and the subcortical gray matters (thalamus, caudate nucleus, amygdala) with inferior limiting (circular) sulcus of insula. Results : The inferior limiting sulcus of insula, limen insulae, medial sylvian groove, and caudate nucleus/amygdala were more appropriate anatomical structures than the roof/dorso-lateral wall of the temporal horn and lateral geniculate body which were used to describe previously for delineating the temporal stem. The particular space located inside the line connecting the inferior limiting sulcus of insula, limen insulae, medial sylvian groove/amygdala, and tail of caudate nucleus could be documented. This space included the extreme capsule, uncinate fasciculus, inferior occipito-frontal fasciculus, anterior commissure, ansa peduncularis, and inferior thalamic peduncle including optic radiations, whereas the stria terminalis, cingulum, fimbria, and inferior longitudinal fiber of the temporal lobe were not passing through this space. Also, this continued posteriorly along the caudate nucleus and limiting sulcus of the insula. Conclusion : The temporal stem is white matter fibers passing through a particular space of the temporal lobe located inside the line connecting the inferior limiting sulcus of insula, limen insulae, medial sylvian groove/amygdala, and tail of caudate nucleus. The three dimensional configurations of the temporal stem are expected to give the very useful anatomical and surgical insights in the temporal lobe.

Morphological Characteristics of Sperm in the Korean Striped Field Mouse, Apodemus agrarius coreae: Possible Role of Sperm Neck in the Movement of Sperm Head

  • 이정훈;손성원
    • Animal cells and systems
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    • 제1권2호
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    • pp.371-379
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    • 1997
  • To investigate the movement of sperm head and the role of sperm neck in forward sperm motility in the Korean striped field mouse, Apodemus agrarius coreae, the morphological characteristics of the cauda epididymal spermatozoa were examined by light microscopy and scanning and transmission electron microscopy. Spermatozoa of A. agrarius coreae were characterized by the conspicuous shape of the acrosome and the long tail compared with those of other rodents. Total length of the sperm was $133\mu{m}$. The sperm head had a curved falciform shape. The head was 8.0${\mu}$m in length, and about 4.0 ${\mu}$m in width. The shape of acrosome had an openerlike form. The sperm tail (125 ${\mu}$m) consisted of four major segments: neck (0.5 ${\mu}$m), middle piece (29.5 ${\mu}$m), and principal piece plus the end piece (95 ${\mu}$m). The outer dense fibers were arranged in a horseshoe fashion, and No. 1, 5, 6, and 9 of the outer dense fibers were larger than the others. The mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the 45 0 angled helical structure. The total number of mitochondrial gyres was 188. In particular, the microfilament structures existed in plasma membrane of the sperm, which was adjacent to the acrosomal region on the nuclear membrane. The segmented columns were surrounded by microfilament structures, and the microfilament bundles were adjacent to the outer membrane of the first mitochondria of middle piece. This study presents for the first time the existence of microfilament structures within the plasma membrane of sperm which is located from the adjacent acrosome region to the connecting piece in sperm neck of Korean striped field mouse, Apodemus agrarius coreae. The present result suggests that the constriction and extension of microfilament in sperm neck as well as the wave-movement of sperm tail may play a role in the movement of sperm head.

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