• Title/Summary/Keyword: Horizontal Edge

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Image-based Water Level Measurement Method Adapting to Ruler's Surface Condition (목자판 표면 상태에 적응적인 영상 기반 수위 계측 기법)

  • Kim, Jae-Do;Han, Young-Joon;Hahn, Hern-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.9
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    • pp.67-76
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    • 2010
  • This paper proposes a image-based water level measurement method, which adapt to the ruler's surface condition. When the surface of a ruler is deteriorated by mud, drifts, or strong light reflection, the proposed method judges the pollution of ruler by comparing distance between two levels: the first one is the end position of horizontal edge region which keeps the pattern of ruler's marking, and the second one is the position where the sharpest drop occurs in the histogram which is construct using image density based on the axis of image height. If the ruler is polluted, the water level is a position of local valley of the section having a maximum difference between the local peak and valley around the second level. If the ruler is not polluted, the water level is detected as the position having horizontal edges more than 30% of histogram's maximum value around the first level. The detected water level is converted to the actual water level by using the mapping table which is construct based on the making of ruler in the image. The proposed method is compared to the ultrasonic based method to evaluate its accuracy and efficiency on the real situation.

Diel Horizontal Migration of Planktonic Copepods in the Surf Zone of Yongil Bay, Korea (영일만 쇄파대에 나타나는 부유성 요각류의 주야 수평이동)

  • Suh Hae-Lip;Yu Ok-Hwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.4
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    • pp.527-536
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    • 1996
  • The patterns of diel horizontal migration (DHM) of 7 copepod species are compared as part of a general investigation of the zooplankton adaptations to the surf zone habitats. In a sandy shore surf zone of Yongil Bay, 3 sites such as the bottom and surface of 1 m water depth and water's edge are sampled with a sledge net(n=108). The surf zone copepod assemblage is dominated by 7 species; Acartia hudsonica, Fseudodiaptomus marinus, Paracalanus indicus, Calanus sinicus, Oithona similis, Sinocalanus tenellus and Labidocera bipinnata. Threefold variations in copepod abundance are observed within a diel cycle. Abundances of 7 dominant species and total copepods captured in the surface exhibit significant diel differences, but those taken in the bottom are not significantly affected by diel period. It is shown that about $90\%$ of the surf zone copepods performed DHM. The nocturnal high densities of copepods occurred for a neap tide when the offshore winds prevailed, suggesting the animals' ability for horizontal orientation and an active locomotion without invoking passive transportation by currents. Photoreactive behavior of copepods triggered by relative changes in light intensity may be a primary factor inducing DHM by aggregating in the surf zone during the night and spreading out at day; then copepods may reduce encounters with visual predators. In A. hudsonica, ontogenetic variations in timings of DHM are evident. Such variations are likely to minimize intraspecific competition for diets. Data on shoreward migration of copepods indicate that A. hudsonica, P. indicus, O. similis and S. tenellus can maintain swimming velocities of about $20m\;h^{-1}$ for durations of more than an hour. Our observations of strong diel difference in abundances point out the need for both day and night samplings in surf zone habitats, if the importance of these habitats to planktonic copepods are to be fully understood.

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Thermal Optimization of a Straight Fin Heat Sink with Bypass Flow (바이패스가 있는 히트 싱크의 열성능 최적화)

  • Kim, Jin-Wook;Kim, Sang-Hoon;Kim, Joong-Nyon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.2
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    • pp.179-184
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    • 2010
  • This experimental study investigated the effect of tip clearance and bypass flow on the cooling performance of a straight fin heat sink. Both the horizontal and vertical directions of the bypass flow were studied by using a mass flow controller and test sections. The thermal resistance of a heat sink was obtained to elucidate the response of the cooling performance to tip clearance and bypass flow. The thermal resistance of a straight fin heat sink gradually increases with increasing tip clearance. A flow guide unit was employed to reduce the bypass flow. An optimal distance from the leading edge of the heat sink to the flow guide unit was found for the fixed volume flow rate. The contribution of the flow guide unit to the thermal performance of a heat sink increases with increasing volume flow rate.

Robust Extraction of Facial Features under Illumination Variations (조명 변화에 견고한 얼굴 특징 추출)

  • Jung Sung-Tae
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.1-8
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    • 2005
  • Facial analysis is used in many applications like face recognition systems, human-computer interface through head movements or facial expressions, model based coding, or virtual reality. In all these applications a very precise extraction of facial feature points are necessary. In this paper we presents a method for automatic extraction of the facial features Points such as mouth corners, eye corners, eyebrow corners. First, face region is detected by AdaBoost-based object detection algorithm. Then a combination of three kinds of feature energy for facial features are computed; valley energy, intensity energy and edge energy. After feature area are detected by searching horizontal rectangles which has high feature energy. Finally, a corner detection algorithm is applied on the end region of each feature area. Because we integrate three feature energy and the suggested estimation method for valley energy and intensity energy are adaptive to the illumination change, the proposed feature extraction method is robust under various conditions.

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Esthetic prosthesis for a patient with the maxillary diastema: a case report (상악의 치간이개를 가진 환자에서의 심미보철 수복 증례)

  • Park, Jae-Ho;Kim, Hyeran;Yun, Kwi-Dug;Shin, Jin-Ho;Lim, Hyun-Pil
    • Journal of Dental Rehabilitation and Applied Science
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    • v.33 no.4
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    • pp.314-320
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    • 2017
  • In the treatment of esthetically important areas such as maxillary anterior teeth, they should be corresponded with surrounding tissues, and shape of the smile line, soft tissue, and hard tissue, also the anatomical shape and proportion of the teeth should be considered as well. Esthetic analysis includes facial analysis which evaluates the proper parallelism between the occlusal plane and the horizontal reference line, dentolabial analysis which assesses the position of the incisal edge and the coherence between the occlusal plane and the commissural line, tooth analysis which evaluates not only esthetics but also morphology and appearance for proper function, and gingival analysis which forms ideal outline of gingival margins. A maxillary anterior diastema can be esthetically restored through the systematic diagnostic approach and treatment planning, and orthodontic, prosthetic, and conservative treatment can be applied for the treatment.

The Development of Ecological Planting Model for the Make Up of Coastal Windbreak Forest on Suncheon Bay in Suncheon-si, Korea (순천만 해안방풍림 조성을 위한 생태학적 식재모델 개발)

  • Kim, Do-Gyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.1
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    • pp.89-104
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    • 2011
  • This study was carried out to the development of ecological planting model to make up of coastal windbreak forest on the Suncheon-bay in Sucheon-si, Korea. Make up of coastal windbreak forest in this site was needed for appropriate bioresource, biodiversity and ecological structure, and for conservation of the eco-tour resource and protection of human life and property by the unforeseen disaster from the coast. Based on the plant-social principle, the planting model of windbreak forest was developed to facilitate growth of trees, considering planting locations. The ecological planting model for the coastal windbreak was composed of warm temperate evergreen and windbreak forest which is spreading around the inland area in Korea. The horizontal forest style was composed of forest edge community and inner forest community, and the vertical forest style was composed of upper, middle, low and ground planting class. The target of the present model was quasi-natural forest, and the species of tree were selected based on the adaptability to surroundings depending on a goal to create a forest and forest style. To achieve both functions of wind break forest and visual effect in short period of time, small trees and seedlings were planted with high-density of 40,000/ha in an expectation of easy natural maintenance in the future. The significance of the present study is a suggestion for a guideline to create ecological coastal windbreak forest in the Suncheon-bay in which the harmony of human life and the ecological conservation is of great importance. Also, the ecological coastal windbreak forest model should be developed further through the long term monitoring after construction of forest.

An Investigation of Icing Effects on the Aerodynamic Characteristics of KC-100 Aircraft (KC-100 항공기의 표면발생 Icing 형상 및 공력 영향성 연구)

  • Jung, Sung-Ki;Lee, Chang-Hoon;Shin, Sung-Min;Myong, Rho-Shin;Cho, Tae-Hwan;Jeong, Hoon-Hwa;Jung, Jae-Hong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.6
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    • pp.530-536
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    • 2010
  • In-flight icing is a critical technical issue for aircraft safety and, in particular, ice accretions on aircraft surfaces can drastically impair aerodynamic performances and control authority. In order to investigate icing effects on the aerodynamic characteristics of KC-100 aircraft, a state-of-the-art CFD code, FENSAP-ICE, was used. A main wing section and full configuration of KC-100 aircraft were considered for the icing analysis. Also, shapes of iced area were calculated for the design of anti-/de-icing devices. The iced areas around leading edge of main wing and horizontal tail wing were observed maximum 7.07% and 11.2% of the chord length of wing section, respectively. In case of wind shield, 16.7% of its area turned out to be covered by ice. The lift of KC-100 aircraft were decreased to 64.3%, while the drag was increased to 55.2%.

A Study on Wind Load Variation Characteristics of Wind Turbine Gearbox (풍력발전기 증속기에 전달되는 풍하중 변동특성 연구)

  • Kim, Jung-Su;Lee, Hyoung-Woo;Park, No-Gill;Lee, Dong-Hwan
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.2
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    • pp.267-275
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    • 2012
  • In this study, normal wind load and blast wind load are modeled mathematical. And the periodical torque and bending moments transmitted to the main shaft of wind turbine are investigated. A normal wind model assumed, of which the wind velocity is increased according to the height from ground. The average values and the harmonic terms of the transmitted moments are studied on the wind direction of range $-45^{\circ}{\sim}45^{\circ}$ and the bending moment characteristics are examined, which is regarded as the main source of the misalignment of gear train. In normal wind load case, excitation frequency is 3X (X : Rotor speed). When the wind direction is $+22.5^{\circ}$, the horizontal axis of bending moment occur the 50% of main torque. This result leads to edge contact of gear teeth by shaft elastic deformation. In blast wind load case, excitation frequency are 3X,6X,9X. Additional, in the (+) direction of wind load, relative harmonic percentage is increase.

Muller's Muscle-Levator Aponeurosis Advancement Procedure for Blepharoptosis (뮐러근과 거근건막의 전진술에 의한 안검하수의 교정)

  • Baik, Bong Soo;Kim, Tae Bum;Hong, Wang Kwang;Yang, Wan Suk
    • Archives of Plastic Surgery
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    • v.32 no.2
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    • pp.219-226
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    • 2005
  • Muller's muscle-levator aponeurosis advancement procedure was performed to correct mild to moderate congenital blepharoptosis with moderate to good levator function and to correct severe aquired blepharoptosis with poor levator function. Through the blepharoplasty incision, the upper half of the tarsal plate was exposed and the orbital septum was opened to show the levator aponeurosis. The Muller's muscle was dissected from the superior margin of the tarsal plate and from the posteriorly located conjunctiva with sharp scissors. The Muller's muscle and levator aponeurosis were advanced on the anterior surface of the tarsal plate as a composite flap and fixed approximately 3 to 4 mm inferior to the upper edge of the tarsal plate with three horizontal 6-0 nylon mattress sutures. The amount of advancement of the composite flap was controlled by the location of the upper eyelid margin 2 mm below the upper limbus in primary gaze after the first suture in the middle portion of the flap. The excess flap was trimmed off with scissors, but trimming was usually not necessary in cases of mild to moderate ptosis. Nine cases underwent this Muller's muscle-levator aponeurosis advancement procedure from September 2003 to September 2004. Five cases were congenital blepharoptosis with 2-4 mm ptosis and more than 5 mm of levator function, but three of the four acquired ptosis cases had more than 4 mm ptosis with poor levator function. The age of the patients ranged from 7 to 81 years. In operative results, all patients except one traumatic case were within 1 mm of the desired eyelid height in primary gaze. This procedure can provide not only tightening of the Muller's muscle but also advancement and firm fixation of the levator aponeurosis to the tarsal plate, yielding predictable results.

An Experimental Study on The Development of fly-ash Cement Mortal Permanent (플라이애쉬 시멘트 모르터를 사용한 비탈형 영구거푸집 개발에 관한 실험적연구)

  • 김형남;김우재;김성식;김영희;정상진
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.481-486
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    • 1999
  • According to results of this research Fly-ash Cement permanent-form production was found to be possible by fly-ash mortal. The compress strength 350kg/$\textrm{cm}^2$, banding strength 120kg/$\textrm{cm}^2$ were possible material separting and bleeding by excessive W/C rate was decreased permanent-form made by polymer solved high price of polymer by fly-ash. Model material was made by result of first research. There were no minute-crack on beam form and out surface of form was very smooth, So filling degree seemed desirable length of form after steaming curing was maintained as expected. with these results production of form seemed possible. In the banding load test, fly-ash showed increase of maxim load 12% than RC. in the case of minute-crack, comparing with RC, fly-ash showed no crack at connect. at the first stage under continuing loading size of crack increased. These phenomena seemed to be based on contribution of stress of inner bars in permanent-form. in the test of defection, fly-ash shower about 10% beam load increase than RC. in the case of beam defection, RC showed sudden decrease of tolerance at maxim load and total breaking, but permanent-form showed breaking of bending maintaining defection with contribution of steel stress ($\Phi$6 wire-mash). There phenomenic seemed to be attributed to increase of surface and steel tolerance of form. According to construction explacemaion, it was guessed that each panel was constructed by conner-steels in form edge. so cohesiveness was small. on these bases. keeping width of horizontal band 30cm, form-panel of 20mm width was found to be of use. Permanent-form was found to be efficient in compressibleness, defection, safety and use of Fly-ash mortal.

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