• Title/Summary/Keyword: 경계 길이

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Structure of the Male Reproductive System in the Freshwater Prawn Macrobrachium nipponense (징거미새우, Macrobrachium nipponense 수컷 생식기의 구조)

  • 김대현;한창희
    • Journal of Life Science
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    • v.8 no.5
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    • pp.582-588
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    • 1998
  • The male reproductive system of Macrobrachium nipponense consists of a pair of lobulate testes enveloped within a mesenteric sheath extending the length of the carapace. The paired vasa deferentia originated from the mid-lateral region of each testis and extended to the genital pores at the base of the fifth walking legs. The vas deferens has four morphologically distinct regions, i.e., a short and slender proximal region, a long convoluted region, an elongate distal region and an ejaculatory duct that terminates at the genital pore. The sperm mass produced in the testes is surrounded by a basophilic matrix adjacent to the high columnar epithelium and an eosinophilic matrix adjacent to the simple columnar epithelium. The sperm cord is stored in the ejaculatory duct until it is ejaculated. Androgenic gland is found near the subterminal region of the ejaculatory duct between the muscles of the coxopodite of the last thoracic leg. The cell of the androgenic gland is about 6~8 $\mu$m in length, characterized by with extended chromatin in the large nucleus that stained weakly with hematoxylin and there is a large quantity of cytoplasm. The sperm of M. nipponense are typical of the palaemonid type, having a convex, cup shaped head and an elongated spike extending from the centre of the convex head. The spermatophore consisted of an eosinophilic matrix, a basophilic matrix and paired sperm masses which was surrounded by the basophilic matrix. It generally shows a bilaterally symmetrical structure.

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The Response of a Single Pile and Pile Groups to Tunnelling Performed in Weathered Rock (풍화암에서 실시된 터널굴착으로 인한 단독말뚝 및 군말뚝의 거동)

  • Lee, Cheol Ju
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5C
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    • pp.199-210
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    • 2012
  • The effects of tunnelling in weak weathered rock on the behaviour of a pre-existing single pile and pile groups ($3{\times}3$ and $5{\times}5$ pile groups) above a tunnel have been studied by carrying out three-dimensional (3D) elasto-plastic numerical analyses. Numerical modelling of such effects considers the response of the single pile and pile groups in terms of tunnelling-induced ground and pile settlement as well as changes of the shear transfer mechanism at the pile-soil interface due to tunnelling. Due to changes in the relative shear displacement between the pile and the soil at the pile-soil interface with tunnel advancement, the shear stresses and axial pile force distributions along the pile change drastically. Based on the computed results, upward shear stresses are induced up to about Z/L=0.775 from the pile top, while downward shear stresses are mobilised below Z/L=0.775, resulting in a reduction in the axial pile force distribution with depth equivalent to a net increase in the tensile force on the pile. A maximum tensile force of about $0.36P_a$ developed on the single pile solely due to tunnelling, where $P_a$ is the service axial pile loading prior to tunnelling. The degree of interface shear strength mobilisation at the pile-soil interface was found to be a key factor governing pile-soil-tunnelling interaction. Overall it has been found that the larger the number of piles, the greater is the effect of tunnelling on the piles in terms of pile settlement, while changes of the axial pile forces for the piles in the groups are smaller than for a single pile due to the shielding effect. The reduction of apparent allowable pile capacity due to tunnelling-induced pile head settlement was significant, in particular for piles inside the groups.

Design and Implementation of a news Archive System using Shot Types (샷의 타입을 이용한 뉴스 아카이브 시스템의 설계 및 구현)

  • Han, Keun-Ju;Nang, Jong-Ho;Ha, Myung-Hwan;Jung, Byung-Hee;Kim, Kyeong-Soo
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.5
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    • pp.416-428
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    • 2001
  • In order to build a news archive system. the news video stream should be first segmented into several articles, ad their contents are abstracted effectively. This abstraction helps the users to understand the contents of the article without playing the whole video stream. This paper proposes a new article boundary detection scheme for the news video streams together with a new news article abstraction scheme using the shot types of the news video data. The shots in the news video are classified into anchor person shots, interview shots, speech shots, reporting shots, graphic shots, and others. Since the news article starts with an anchor shot whose duration is relatively longer than other shots with special screen structure, the article boundary in detected by the computing the length of the shot and checking the screen structure in the proposed scheme. For the effective abstraction of the article video, the graphic image located in the right-top of the anchor shot frames is primarily used in the proposed abstraction scheme since it is the abstraction of the article made by the producer of the news according to its contents so that it contains a lot of meaningful information. The key frames of the other shots except interview and report shots are also used to abstract the contents of the articles in the proposed scheme. Upon experimental results, the precision and recall values of the proposed article boundary detection scheme could be 92% and 96%, respectively. This paper also presents a design and implementation of a prototype news archive system on WWW that consists of an indexing tool, an authoring tool, a database for meta-data of the news, and a browsing tool.

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Geometry Design of a Pitch Controlling Type Horizontal Axis Turbine and Comparison of Power Coefficients (피치각 제어형 수평축 조류 터빈의 형상설계 및 출력계수 비교)

  • Park, Hoon Cheol;Truong, Quang-Tri;Phan, Le-Quang;Ko, Jin Hwan;Lee, Kwang-Soo;Le, Tuyen Quang;Kang, Taesam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.17 no.3
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    • pp.167-173
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    • 2014
  • In this work, based on the blade element-momentum theory (BEMT), we proposed the geometry of a lab-scale horizontal axis tidal turbine with a diameter of 80cm, which can demonstrate the maximum power coefficient, and investigated the effect of blade pitch angle increase on the power coefficient. For validation of the computed power coefficients by the BEMT, we also computed the power coefficient using the computational fluid dynamics (CFD) for each case. For the CFD, 15 times of the turbine radius was used for the length and diameter of the computational domain, and the open boundary condition was prescribed at the boundary of the computational domain. The maximum power coefficients of the turbine acquired by the BEMT and CFD were about 48%, showing a good agreement. Both of the power coefficients computed by the BEMT and CFD tended to decrease when the blade pitch angle increases. The two power coefficients for a given tip-speed ratio were in good agreement. Through the present study, we have confirmed that we can trust the proposed geometry and the computed power coefficients based on the BEMT.

Shear Behavior of Sands Depending on Shear Box Type in Direct Shear Test (직접전단실험시 전단상자의 종류에 따른 모래시료의 전단거동)

  • Hong, Young-Ho;Byun, Yong-Hoon;Chae, Jong-Gil;Lee, Jong-Sub
    • Journal of the Korean Geotechnical Society
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    • v.31 no.3
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    • pp.51-62
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    • 2015
  • Shear behavior obtained by direct shear tests is dependent on shear box and boundary condition. The objective of this study is to analyze problems of conventional direct shear test (type-A) and provide the reliable results by developing type-C direct shear apparatus. Experimental tests are carried out for Ulleung sand by using type-A and -C direct shear devices. The soil specimens, which are prepared at the relative density of 60%, and are applied to vertical confining stresses of 50, 100, 200, 300, and 400 kPa, are sheared at a constant shear strain rate of 0.5 mm/min. By comparing the results obtained by type-A and -C direct shear apparatus under constant normal load (CNL) condition, the performance of new one is verified. In addition, two constrained conditions including constant normal load (CNL) and constant pressure (CP) are applied to type-C one. Experimental results show that type-A direct shear apparatus has some problems such as rotating of loading plate and upper shear box, and the frictional forces between soil and inner wall of upper shear box. Thus, the shear strengths obtained by type-A device are overestimated or underestimated depending on shear box and boundary condition. On the other hand, type-C device produces clear and consistent test results regardless of constrained conditions. This study represents that type-C direct shear apparatus not only can solve the problems of type-A direct shear apparatus but provide the reliable results.

Seam-line Determination in Image Mosaicking using Adaptive Cost Transform and Dynamic Programming (동적계획법과 적응 비용 변환을 이용한 영상 모자이크의 seam-line 결정)

  • Chon, Jae-Choon;Suh, Yong-Cheol;Kim, Hyong-Suk
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.2
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    • pp.16-28
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    • 2004
  • A seam-line determination algorithm is proposed to determine image border-line in mosaicing using the transformation of gray value differences and dynamic programming. Since visually good border-line is the one along which pixel differences are as small as possible, it can be determined in association with an optimal path finding algorithm. A well-known effective optimal path finding algorithm is the Dynamic Programming (DP). Direct application of the dynamic programming to the seam-line determination causes the distance effect, in which seam-line is affected by its length as well as the gray value difference. In this paper, an adaptive cost transform algorithm with which the distance effect is suppressed is proposed in order to utilize the dynamic programming on the transformed pixel difference space. Also, a figure of merit which is the summation of fixed number of the biggest pixel difference on the seam-line (SFBPD) is suggested as an evaluation measure of seamlines. The performance of the proposed algorithm has been tested in both quantitively and visually on various kinds of images.

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Do the Rotating Hinge-Flexible Intramedullary Nail Composites Alleviate Junctional Osteolysis in Megaprothesis Reconstruction for Bone Tumor? (탄력성 있는 골수강 내고정물과 회전경첩형 슬관절 전치환물을 조합한 종양인공관절로 자가골의 골 용해를 감소시킬 수 있는가?)

  • Song, Won-Seok;Cho, Wan-Hyeong;Cho, Sang-Hyun;Jeon, Dae-Geun
    • The Journal of the Korean bone and joint tumor society
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    • v.13 no.2
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    • pp.96-104
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    • 2007
  • Purpose: The authors investigated whether 35 flexible nail-rotating hinge composite reconstructions around knee joint minimize junctional osteolysis of host bone. Material and Method: The reconstructive technique was as follows: 1) en bloc tumor resection, 2) filling of the host bone marrow cavity with multiple Ender nails, 3) assembling the Ender nails and an Endo-Link type total knee component with wire and bone cement. Result: Mean follow-up was 53 months (ranged 30~79). At final follow-up, 29 patients retained a mobile joint. Resection of more than 40% of bone showed a positive relationship with junctional hypertrophy (p=0.028). Eight patients showed nail breakage and eight prostheses were removed due to early or late infection. The cumulative prosthetic survival rate was 33% at 6 year. Average functional score according to the MSTS criteria was 26.8. Conclusion: Mid-term evaluations showed that results were fair. The revision process was straightforward. Junctional hypertrophy observed appears to give some clues as to how to minimize osteolysis at the prosthesis-host junction after modular prosthesis fixation.

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Design Study of Engine Inlet Duct for Measurement Improvement of the Flow Properties on AIP (AIP면 유동측정 정확도 향상을 위한 가스터빈엔진 입구덕트 설계 연구)

  • Im, Ju Hyun;Kim, Sung Don;Kim, Yong Ryeon
    • Journal of the Korean Society of Propulsion Engineers
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    • v.21 no.3
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    • pp.49-55
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    • 2017
  • In this study, gas turbine engine inlet duct was designed to satisfy uniform flow at aerodynamic interface plane (AIP). Haack-series was selected as nose cone profile and duct outer radius($r_o$) was designed to satisfy to match with area change rate between the nose cone and outer duct wall by the 1-D sizing. The design object of the inlet duct wall profile which has the gradual area change rate was uniform Mach number in the core flow region and minimum boundary later thickness at the both inner nose wall and outer duct wall. The flow characteristics inside the inlet duct was evaluated using CFD. The static pressure distribution at the AIP showed uniform pattern within 0.16%. Based on Mach number profile, the boundary layer thickness was 2% of channel height. Kiel temperature rake location was decided less than 100 mm in front of nose cone where the Mach number is less than 0.1 in order to maximize the temperature probe recovery rate.

Image Processing and Deep Learning Techniques for Fast Pig's Posture Determining and Head Removal (돼지의 빠른 자세 결정과 머리 제거를 위한 영상처리 및 딥러닝 기법)

  • Ahn, Hanse;Choi, Wonseok;Park, Sunhwa;Chung, Yongwha;Park, Daihee
    • KIPS Transactions on Software and Data Engineering
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    • v.8 no.11
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    • pp.457-464
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    • 2019
  • The weight of pig is one of the main factors in determining the health and growth state of pigs, their shipment, the breeding environment, and the ration of feed, and thus measuring the pig's weight is an important issue in productivity perspective. In order to estimate the pig's weight by using the number of pig's pixels from images, acquired from a Top-view camera, the posture determining and the head removal from images are necessary to measure the accurate number of pixels. In this research, we propose the fast and accurate method to determine the pig's posture by using a fast image processing technique, find the head location by using a fast deep learning technique, and remove pig's head by using light weighted image processing technique. First, we determine the pig's posture by comparing the length from the center of the pig's body to the outline of the pig in the binary image. Then, we train the location of pig's head, body, and hip in images using YOLO(one of the fast deep learning based object detector), and then we obtain the location of pig's head and remove an outside area of head by using head location. Finally, we find the boundary of head and body by using Convex-hull, and we remove pig's head. In the Experiment result, we confirmed that the pig's posture was determined with an accuracy of 0.98 and a processing speed of 250.00fps, and the pig's head was removed with an accuracy of 0.96 and a processing speed of 48.97fps.

Expected Segmentation of the Chugaryung Fault System Estimated by the Gravity Field Interpretation (추가령단층대의 중력장 데이터 해석)

  • Choi, Sungchan;Choi, Eun-Kyeong;Kim, Sung-Wook;Lee, Young-Cheol
    • Economic and Environmental Geology
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    • v.54 no.6
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    • pp.743-752
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    • 2021
  • The three-dimensional distribution of the fault was evaluated using gravity field interpretation such as curvature analysis and Euler deconvolution in the Seoul-Gyeonggi region where the Chugaryeong fault zone was developed. In addition, earthquakes that occurred after 2000 and the location of faults were compared. In Bouguer anomaly of Chugaryeong faults, the Pocheon Fault is an approximately 100 km fault that is extended from the northern part of Gyeonggi Province to the west coast through the central part of Seoul. Considering the frequency of epicenters is high, there is a possibility of an active fault. The Wangsukcheon Fault is divided into the northeast and southwest parts of Seoul, but it shows that the fault is connected underground in the bouguer anomaly. The magnitude 3.0 earthquake that occurred in Siheung city in 2010 occurred in an anticipated fault (aF) that developed in the north-south direction. In the western region of the Dongducheon Fault (≒5,500 m), the density boundary of the rock mass is deeper than that in the eastern region (≒4,000 m), suggesting that the tectonic movements of the western and eastern regions of the Dongducheon Fault is different. The maximum depth of the fracture zone developed in the Dongducheon Fault is about 6,500 m, and it is the deepest in the research area. It is estimated that the fracture zone extends to a depth of about 6,000 m for the Pocheon Fault, about 5,000 m for the Wangsukcheon Fault, and about 6,000 m for the Gyeonggang Fault.