• Title/Summary/Keyword: Head shape

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Analysis of Optical Flying Head Dynamics for Near-field Receding System (근거리장 광부상 헤드의 Loading 동특성 해석)

  • 은길수;김노유
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.175-180
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    • 2002
  • Loading/Unloading(L/UL) mechanism has been considered to be an alternative to contact start-stop(CSS) mechanism which eliminates stiction and wear associated with frequent start and stop process. It has other advantages including increased areal density due to lower flying height, reduced power consumption, and improved shock resistance. In order for L/UL to be Implemented in Near-field recording system properly, dynamics of optical flying head must be understood and optimized. In this paper the dynamic characteristics during loading process is analyzed numerically to investigate the effect of design parameters such as loading speed. slider shape, and initia conditions on the dynamic reponses of flying head..

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Development of Optical Head Unit for Nano Optical Probe Array (나노 광 프로브 어레이 구현을 위한 광학 헤드 유닛 개발)

  • Kim H.;Lim J.;Kim S.;Han J.;Kang S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2005.09a
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    • pp.29-34
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    • 2005
  • A optical head unit for nano optical probe away was developed. The optical probe array is generated by Talbot effect. The shape and thickness of microlens array(MLA) were designed to minimize the spot size at the foci of MLA. To increase the optical efficiency of the system and obtain the large tolerance for fabrication, aperture size was theoretically optimized. Then microlens illuminated aperture array(MLIAA) as an optical head unit was fabricated using a ultra violet(UV) molding process on aluminum aperture array. In this process, Al aperture array was fabricated separately using the photolithography and reactive ion etching(RIE) process. Optical properties of the generated optical probes were measured and compared at Talbot distance from the aperture array having a diameter of $1{\mu}m$ and MLIAA.

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Usefulness of Narrow Band Imaging Endoscopy in the Diagnosis of Head and Neck Cancer : A Prospective Study (두경부암 진단의 새로운 내시경 진단방법 협대역 영상(Narrow Band Imaging, NBI)의 유용성-전향적 연구)

  • Park, Jae-Hong;Kim, Jae-Wook;Lee, Yong-Man;Yoo, Hye-Jin;Tae, Kee-Yeun;Oh, Cheon-Whan;Chang, Hyuck-Soon;Lee, Seung-Won
    • Korean Journal of Head & Neck Oncology
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    • v.27 no.2
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    • pp.210-214
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    • 2011
  • Background and Objectives : Narrow Band Imaging(NBI) is a novel optical technique that enhances the visualization of superficial microvascular architecture which is commonly increased and founded as an irregular shape in a neoplastic lesion. The aim of this study is the evaluation of the usefulness of NBI in the diagnosis of Head and Neck Cancer. Subjects and Methods : From December 2009 to January 2011, 31 consecutive patients who were diagnosed with head and neck malignancy were enrolled in this prospective study. The malignant findings of NBI were demarcated brownish lesion or increased intraepithelial papillary capillary loops(IPCLs) with or without irregularity. Results : There were 29 cases(93.5%) of well demarcated brownish lesion, 26 cases(83.9%) of increased IPCLs and 4 cases(12.9%) of satellite lesions. Diagnostic accuracy of endoscopic examination was increased from 83.9% to 93.5%, when NBI was applied to the conventional endoscopy(p>0.05). Conclusion : NBI is a powerful and safe screening test, which can be performed in out patient clinic without any supplementary procedure.

감귤저장시 부패균 증식억제를 위한 식물유래 천연항균제 탐색

  • Ha, Cheol-Gyu;Lee, Dong-Gyu;Gang, Seon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.453-456
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    • 2000
  • Antifungal activities of domestic plants were examined to develope natural antimicrobial agents, able to protect citrus fruits from spoiling microorganism during their storage. A fungus was isolated from citrus fruits' storage and identified to Penicillium sp. CF-301, based on the morphological characteristics of conidiophore and conidia; flask shape of phialide, simple branching type of conidiophore, and columnar shape of conidial head, in malt extract agar and potato dextrose agar media. Chloroform extracts of Juniperus chinesis Linnaeus, J. chinesis var. horizontalis showed remarkable antifungal activities against Penicillium sp. CF-301.

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Sperm Morphology of Two Species of the Genus Apodemus (Rodentia, Mammalia) in Korea (한국산 붉은쥐속 2종의 정자의 형태)

  • 양병국;정현덕고흥선
    • The Korean Journal of Zoology
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    • v.34 no.1
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    • pp.59-63
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    • 1991
  • Sperm morphology of ho species (hpodemus agrarius coreae and Apodemus peninsulae peninsulae) of the genus Apodrmus in Korea was investigated. Two species were similar in six qualitative characters, i. e., head shape, presence of apical ridge, process, cone-like process, and mitochondrial sheath, and the degree of development in outer dense Hber, Lengths of head and midpiece were not different with each other, but length of principal plus end piece was significantly larger (P ≪ 0.001) in hpodemus agrarius coreae than that in hpodemus peninsular peninsulae.

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Diagnosis of Legg-Calve-Perthes Disease in 2 Dogs (개의 Legg-Calve-Perthes Disease 진단 2례)

  • 윤정희;이영원;이희천;김종민;권오경;성재기
    • Journal of Veterinary Clinics
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    • v.13 no.1
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    • pp.93-95
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    • 1996
  • Legg-Calve-Perthes diseases were diagnosed in 2 dogs showing signs of lameness. In radiographs, the abnormal size and shape was due to the collapse of the left capital bone and enlarged femoral neck was seen at case I. The completely deformed left femoral head resulted from the earlier collapse of the osteolytic bone of the caput femoris at case II. In treatment, femoral head ezcision was performed in one dog.

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Three-dimensional Head Tracking Using Adaptive Local Binary Pattern in Depth Images

  • Kim, Joongrock;Yoon, Changyong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.16 no.2
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    • pp.131-139
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    • 2016
  • Recognition of human motions has become a main area of computer vision due to its potential human-computer interface (HCI) and surveillance. Among those existing recognition techniques for human motions, head detection and tracking is basis for all human motion recognitions. Various approaches have been tried to detect and trace the position of human head in two-dimensional (2D) images precisely. However, it is still a challenging problem because the human appearance is too changeable by pose, and images are affected by illumination change. To enhance the performance of head detection and tracking, the real-time three-dimensional (3D) data acquisition sensors such as time-of-flight and Kinect depth sensor are recently used. In this paper, we propose an effective feature extraction method, called adaptive local binary pattern (ALBP), for depth image based applications. Contrasting to well-known conventional local binary pattern (LBP), the proposed ALBP cannot only extract shape information without texture in depth images, but also is invariant distance change in range images. We apply the proposed ALBP for head detection and tracking in depth images to show its effectiveness and its usefulness.

Silhouette differences among cats do not suggest a general selection for paedomorphosis

  • Pares-Casanova, Pere M.
    • Korean Journal of Veterinary Research
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    • v.53 no.3
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    • pp.155-158
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    • 2013
  • Paedomorphosis is the retention of juvenile morphology at maturity and is important in generating evolutionary change in domestic species and species in the wild. This preliminary study compared morphological characteristics of seven domestic cat pure breeds and felid species from around the world. An original procedure based on elliptical Fourier (EF) methods was applied to head lateral views of specimens and were assessed in order to analyse head profile. For comparative purposes three domestic kittens of different ages and three species of genus Lynx were also used. EF descriptors, allowed for the quantification of the head profile. Using the Fourier transform, reconstruction of the mean head profile revealed that there was a general shape difference between wild cats, domestic cats and kittens. Results suggested that variability in head profile differentiate quite well between adult cats and kittens, but domestic and wild cats appeared grouped into a similar cluster. The similarity between breeds can thus be attributed more to the general head profile than to flatness, i.e. to the general conformation rather than facial profile. Therefore, no effect of paedomorphism on the studied breeds can be undertaken. The present approach opens interesting ethnological perspectives for the aloidic characterisation for domestic breeds.

Electron Microscopic Study on the Spermiogenesis of Cipangopaludina chinensis malleata (Reeve) (논우렁이[Cipangopaludina chinensis malleata (Reeve)]의 精蟲形成 過程에 관한 電子顯微鏡的 硏究)

  • Kim, Ju-Hee;Park, Won-Chul
    • The Korean Journal of Zoology
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    • v.29 no.2
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    • pp.121-140
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    • 1986
  • The spermiogenesis of Cipangopaludina chinensis malleata began with the changes of nucleus and cytoplasm. The chromatin in the nucleus began to stack and condense around perinuclear envelope. Axonema (doublet microtubules of 9+2) appeared in the cytoplasm. After this process, the cytoplasm was protruded and the bell-shaped nucleus was located on protruding part of it. The electron dense masses were distributed throughout cytoplasm and lysed or secreted by exocytosis of lysosomal vacuoles. Especially, some mitochondria were migrated by the doublet microtubules of axonema toward nucleus. The axoneme was enclosed by electron dense materials after exocytosis of unnecessary materials for the tail formation. The electron dense masses were released and migrated into the each part through microtubules or axonemal doublet microtubules as the granular particles. These granular particles were containing glycogen. Ultimately, the condensed head developed into helical and neck region into cylindrical shape respectively. The mitochondria which have regular lamellar layers at cross axis became to middle piece, and then spermatozoon was completely matured. Thus, these phenomena showed special processes in spermiogenesis, those were as follows; chromatin in the head was condensed, the head was changed into helical shape, and cytoplasmic materials are migrated and transferred into the each part in the tail by mitochondria and microtubules.

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Analysis of the Net Mouth Shape for a Midwater Trawl Gear (중층 트롤 어구의 망구 형상 해석)

  • 김인진;이춘우
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.2
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    • pp.118-128
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    • 1999
  • The shape of the net mouth in a midwater trawl gear is examined by measuring towing speed, gear resistance, the width of otter boards, net height, and so on of a full-scale gear in operation. In addition, a mathematical model is developed to predict shapes of the net mouth. In the model, shapes of head, ground, side ropes, which governs the shape of net mouth, are assumed as a catenary. The validity of the model is tested with observations. The results can be summarized as follows: 1. The warp tension and vertical opening of the gear is highly dependent to the towing speed. The depth of the gear and width of otter boards are very sensitive to the variations of the warp length. 2. The model results indicate that the wing tip of the head and side ropes is reduced and the vertical distances of the head and side ropes sagged to the back with increasing towing speed. 3. The results of comparing the measured net height with calculated side rope height were satisfying. 4. The results of analysis showed the vertical axis of the net mouth was decreased and the width of the net mouth was little changed when the towing speed increased.

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