• 제목/요약/키워드: anatomical properties

검색결과 130건 처리시간 0.028초

국내산 대나무 3종의 해부학적 특성 (Anatomical Characteristics of Three Korean Bamboo Species)

  • 전우석;김윤기;이주아;김아란;;정우양;김남훈
    • Journal of the Korean Wood Science and Technology
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    • 제46권1호
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    • pp.29-37
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    • 2018
  • 본 연구에서는 주요 바이오매스 자원의 하나인 대나무의 효율적 활용을 위한 기초자료를 수집하기 위하여, 국내산 대나무 3종(맹종죽, 솜대 및 왕대)의 해부학적 특성을 광학현미경 및 주사전자현미경으로 비교 분석하였다. 또한 X선 회절법에 의해 셀룰로오스의 결정특성을 분석하였다. 횡단면 관찰 결과, 3종 모두 유관속 I형으로 종간 동일한 형태를 보였다. 또한 횡단면의 내측부에서 외측부로 갈수록 유관속의 출현빈도가 더 높았고, 유관속을 둘러싸고 있는 유관속초의 비율도 커졌다. 구성세포 치수 측정 결과, 섬유길이는 모든 종에서 외측부의 값이 내측부의 값보다 컸으며, 내측부와 외측부 모두 왕대의 섬유길이가 가장 길었다. 섬유길이의 유의성 검정 결과 3종 모두 내측부와 외측부간에 유의성이 나타났다. 횡단면에서 측정한 도관 직경 및 유세포 직경은 맹종죽의 값이 가장 컸으며, 방사 및 접선단면에서 측정한 유세포 길이 및 폭은 맹종죽과 왕대가 유사한 값을 나타냈고, 솜대가 가장 작았다. 셀룰로오스의 결정특성 분석 결과 상대결정화도 및 결정 폭은 외측부가 내측부에 비해 다소 높았으며, 왕대의 상대결정화도 및 결정 폭이 다른 2종에 비해 다소 높았다.

임상가를 위한 특집 2 - 형태 해부학적 특징을 바탕으로 한 자연치형 지르코니아 임플란트 (Natural Tooth Form Zirconia Implant Based on Anatomical Morphology)

  • 박영석;이승표
    • 대한치과의사협회지
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    • 제52권9호
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    • pp.541-549
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    • 2014
  • The restorative treatment using titanium implants has become a standard procedures in everyday clinical practice. However, there are several concerns about the use of titanium as a materials. Above all, the grayish metal color provokes esthetic problems when the soft tissue around the implants is not optimal. Recently, zirconia has been emerging as an alternative to titanium due to its white color and superior physicochemical properties. In this paper, the current findings about zirconia implants was reviewed based on the results from animal and clinical experiments. In addition, the immediate implantation protocols using the natural tooth form zirconia implants was introduced as a novel procedures and future perspectives were discussed.

Estimation of the Chestnut Mass Transfer Coefficient through its Microscopic Structure - Chestnut Mass Transfer Coefficient through its Microscopic Structure -

  • Xu, Hui Lan;Chung, Woo-Yang
    • Journal of the Korean Wood Science and Technology
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    • 제40권5호
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    • pp.352-362
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    • 2012
  • Mass transfer behavior in wood was estimated through its microscopic structure. The diffusion coefficients which were decided by theoretical equations are influenced by different anatomical properties of wood. From the experiment, the moisture flux was linear to the square root of time. The diffusion coefficients had a regular tendency during the time elapse. During the modeling, it is necessary to understand the limitation of parameters and consider the particular situation to be simulated. In hardwood, because the apertures were not considered, tangential mass transfer simulation was totally different from experiment. As a result, a hardwood model design should consider the apertures which are even on the fiber walls.

손의 기능 해부에 대한 연구 (A Study of the Functional Anatomy of the Hand)

  • 박영한;이효정
    • 대한물리치료과학회지
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    • 제13권1호
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    • pp.61-74
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    • 2006
  • This study about functional anatomy of the hand. hand injuries are among the most common problems confronting patient, physical therapist and physicians. physical therapist should know about normal hand function and anatomical structure for hand injury, clinical reasoning and intervention. physical therapist should know about the Skeletal of the hand, Function of The Hand, Nerves of the hand, Sensation of the Hand, Intrinsic muscle, Power and Balance and Functional Position of the Hand. In this article, we discuss the physiologic properties of hand structure, biomechanical observation in hand function, sensation and nerves, hand positioning.

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곡률 정보를 이용한 뇌의 3차원 모델 구성 (Reconstruction of 3D Brain Model using Curvature Information)

  • 안광옥;정현교
    • 대한의용생체공학회:의공학회지
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    • 제29권2호
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    • pp.146-150
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    • 2008
  • In order to study cortical properties in human, it is necessary to obtain an accurate and explicit representation of the cortical surface in individual subjects. Among many approaches, surface-based method that reconstructs a 3-D model from contour lines on cross-section images is widely used. The conventional method detects match points of contours using the minimum straight distance between any pair of contour points which lie on different contours. Then, it generates a triangle strip. In general, however, it might yield small mismatches between contours in case of brain due to complex anatomical structures. In this paper, therefore, we present an improved method for tilting operation that uses the curvature values calculated from surface information. The usefulness of the proposed method has been verified using brain image.

Automatic Segmentation of Vertebral Arteries in Head and Neck CT Angiography Images

  • Lee, Min Jin;Hong, Helen
    • Journal of International Society for Simulation Surgery
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    • 제2권2호
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    • pp.67-70
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    • 2015
  • We propose an automatic vessel segmentation method of vertebral arteries in CT angiography using combined circular and cylindrical model fitting. First, to generate multi-segmented volumes, whole volume is automatically divided into four segments by anatomical properties of bone structures along z-axis of head and neck. To define an optimal volume circumscribing vertebral arteries, anterior-posterior bounding and side boundaries are defined as initial extracted vessel region. Second, the initial vessel candidates are tracked using circular model fitting. Since boundaries of the vertebral arteries are ambiguous in case the arteries pass through the transverse foramen in the cervical vertebra, the circle model is extended along z-axis to cylinder model for considering additional vessel information of neighboring slices. Finally, the boundaries of the vertebral arteries are detected using graph-cut optimization. From the experiments, the proposed method provides accurate results without bone artifacts and eroded vessels in the cervical vertebra.

좌주간부 관상동맥에 관한 혈류역학적 분석 (I) (Hemodynamic Analysis of Pig's Left Common Coronary Artery (I))

  • 박정수;장주희;문수연;신세현
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1923-1929
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    • 2003
  • The present study investigated the microcirculation of blood in the left common artery (LCCA). In order to develop a mathematical model for microcirculation in LCCA, the present study adopted preexisted set of measured morphological data on anatomy, mechanical properties of the coronary vessels, viscosity of blood, the basic laws of physics, and the appropriate boundary conditions. In this study, the statistical distribution of blood pressure, blood flow, and blood volume in the LCCA were determined based on the anatomical branching pattern of the coronary arterial tree and the statistical data of blood vessel dimensions. Our calculations were in good agreement with the previous studies. The present results showed that the mean longitudinal pressure drop profile was function of the vessel order numbers. It was found that the normalized pressure drop was a logarithmic function of the compliance.

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Pharmacognostic Evaluation of the Flower of Alcea rosea L.

  • Mehrotra, Shanta;Rawat, A.K.S.;Shome, Usha
    • Natural Product Sciences
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    • 제5권1호
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    • pp.39-47
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    • 1999
  • The flowers of Alcea rosea L., Malvaceae, sold in the Indian market under the trade name 'Gulkhairo', are well known for their expectorant, cooling and diuretic properties and used in many indigenous cough mixtures in India. The present paper deals with the detailed pharmacognosy of the floral parts including morphological, anatomical, phytochemical and fluorescence characters. Some of the diagnostic features of the drug are : pedicel characterized by multicellular appendages, stellate hairs, rosette crystals of Ca-oxalate, starch sheath and large sized mucilage canals; sepals having distinctive multicellular appendages arranged in a semilunar fashion present adaxially at their base; monadelphous stamens, pollen grains pentaporate provided with dimorphic spines; placentation axile, ovules campylotropous; dark green fluorescence of the powder with nitrocellulose in amyl acetate and yellow fluorescence of trichomes under Fluorescence microscope.

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택사의 생약학적 연구 (Pharmacognostical Studies on Alisma Plants)

  • 도정애
    • 생약학회지
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    • 제26권4호
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    • pp.411-418
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    • 1995
  • In order to clarify the originality of several Alisma Rhizomes, we investigated the differences of their morphological, anatomical and physiochemical characteristics. Morphological observation shows the variability of Alisma shape and quality. The diversities in morphological shapes and qualities of tuber were observed among different origins. Chinese product looked like corm shape, but korean's irregular shape. The microscopic observation of korean Alisma revealed the presence of irregular vascular bundle which was scattered transversely and longitudinaly, which was different from that of the rhizome. This facts suggest that the portion of crude drug in Alisma should be the corm rather than the rhizome. In the physicochemical differences, chinese Alisma contains larger amount of mineral elements such as K, Na and Ca than korean Alisma. On the contrary, protein contents in lyophilized powder of aqueous extracts in korean Alisma rhizome was significantly higher than chinese Alisma rhizome. The leaves and stems contained larger amount of Ca and Na than tuber, and may be used as the osmotic diuretics for chinese traditional medicine.

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음원 파라미터 모델과 인공신경망을 이용한 음성장애 검출 (Screening of Voice Disorder using Source Parameter Model and Artificial Neural Network)

  • 파벨시틸;조철우;미샤파벨
    • 음성과학
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    • 제15권2호
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    • pp.89-97
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    • 2008
  • There is a number of clinical conditions that affect directly or indirectly the physical properties of the vocal folds and thereby the pressure waveforms of elicited sounds. If the relationships between the clinical conditions and the voice quality are sufficiently reliable, it should be possible to detect these diseases or disorders. The focus of this paper is to determine the set of features and their values that would characterize the speaker's state of vocal folds. To the extent that these features can capture the anatomical, physiological, and neurological aspects of the speaker they can be potentially used to mediate an unobtrusive approach to diagnosis. We will show a new approach to this problem supported with results obtained from two disordered voice corpora.

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