• Title/Summary/Keyword: segment

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Study on flexible segment efficiency for seismic performance improvement of subsea tunnel (해저터널 내진성능 향상을 위한 Flexible segment 효용성 연구)

  • Jang, Dong-In;Kim, Jong-Ill;Kwak, Chang-Won;Park, Inn-Joon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.3
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    • pp.503-515
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    • 2017
  • Underground structures that have recently become larger are required to be stable not only during normal times but also during earthquakes. Especially, it is very important to maintain the stability of the subsea tunnels during the earthquake. The objective of this paper is to verify the effectiveness of the flexible segment, which is one of the breakthrough facilities to maintain the stability of the subsea tunnel during the earthquake using the shaking table test. Another goal of this paper is to propose the optimum position of the flexible segment through 3D dynamic numerical analysis based on the verified results from shaking table tests. The 1g shaking table test considering the similarity ratio (1:100) to the cross section of the selected artificial subsea tunnel was carried out considering the Geongju and Artificial seismic waves, longitudinal and lateral wave, and with/without flexible segments eight times or more. As a result of the shaking table test, it was confirmed that the flexible segment is effective in improving the seismic performance of the undersea tunnel in all the experimental results. In addition, 3D dynamic numerical analysis was performed to select the optimum position of the flexible segment which is effective for improving seismic performance. As a result, it was confirmed that the seismic acceleration is attenuated when the flexible segment is installed adjacent to the branch section in subsea tunnel.

Biodynamic Characteristics of Korean Male in Twenties-Mass, Center of Mass and Moment of Inertia Characteristics of Body Segments (한국인 20대 청년 인체분절의 관성특성에 관한 연구)

  • 이영신;임현균;김철중
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.8
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    • pp.1952-1966
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    • 1994
  • The body segment parameters of twelve young male Korean were measured to compare with the results of foreign cadaver studies. A human body was assumed to have fourteen body segments. The mass of each segment was measured with a water immersion test and the mass center of a segment was determined on the balance platform by changing postures. In the case of Korean, because of the difference in body proportion, the mass center of whole-body is located further from the distal end of head(Korean : 44.9% vs. Caucasian : 41.2%), and the mass center of each segment also located in different proportional locations. The existing regression equations, which can estimate segment mass based upon the anthropometric dimensions, estimates segment mass (the mass of shank) for Korean with 13% error. Therefore, it is not recommended to estimate the mass, and the moment of inertia of body segment of Korean based on the existing equations. However, the density information of body constituents was similar enough to apply it to Korean density. It was validated by the comparison between the results of the direct immersion method and 3-dimensional volume reconstruction of segment form the cross sectional images of CT-scan. The average body density measured form twelve subjects was $1.035{\;}kg/m^3$ and showed deceasing trendency.

Automatic Recognition of Hand-written Hangout by the Phase Rotation (위상회전에 의한 필기체 한글의 자동인식)

  • 이주근;김홍기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.13 no.1
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    • pp.23-30
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    • 1976
  • In this paper, a method is proposed for the recognition of hand-written Hangeul. This is peiformed by extraction of the concave structural segments by phase rotation. Character patterns can be decomposed into the fundamental concave structural segments which are also categorized into segment sects, and the closure and phase features of each segment in set is represented by logics. By rotating the logic pattern, the topological and phase features of segment are extracted for the reliable recognition of the character. It is also evaluated that this method applies to a wide variety of shape, position and declination of the character.

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Marine birnavirus (MABV)'s 5' terminal region of segment A acts as internal ribosome entry site (IRES)

  • Kim, So Yeon;Kim, Ki Hong
    • Journal of fish pathology
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    • v.34 no.1
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    • pp.17-22
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    • 2021
  • Eukaryotic translation is initiated by either cap-dependent or cap-independent way, and the cap-independent translation can be initiated by the internal ribosomal entry site (IRES). In this study, to know whether the 5'UTR leader sequence of marine birnavirus (MABV) segment A and segment B can act as IRES, bicistronic vectors harboring a CMV promoter-driven red fluorescent gene (mCherry) and poliovirus IRES- or MABV's leader sequence-driven green fluorescent gene (eGFP) were constructed, then, transfected into a mammalian cell line (BHK-21 cells) and a fish cell line (CHSE-214 cells). The results showed that the poliovirus IRES worked well in BHK-21 cells, but did not work in CHSE-214 cells. In the evaluation of MABV's leader sequences, the reporter eGFP gene under the 5'UTR leader sequence of MABV's segment A was well-translated in CHSE-214 cells, indicating 5'UTR of MABV's segment A initiates translation in the cap-independent way and can be used as a fish-specific IRES system. However, the 5'UTR leader sequence of MABV's segment B did not initiate translation in CHSE-214 cells. As the precise mechanism of birnavirid IRES-mediated translation is not known, more elaborate investigations are needed to uncover why the leader sequence of segment B could not initiate translation in the present study. In addition, further studies on the host species range of MABV's segment A IRES and on the screening of other fish-specific IRESs are needed.

Radiologic Findings and Risk Factors of Adjacent Segment Degeneration after Anterior Cervical Discectomy and Fusion : A Retrospective Matched Cohort Study with 3-Year Follow-Up Using MRI

  • Ahn, Sang-Soak;So, Wan-Soo;Ku, Min-Geun;Kim, Sang-Hyeon;Kim, Dong-Won;Lee, Byung-Hun
    • Journal of Korean Neurosurgical Society
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    • v.59 no.2
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    • pp.129-136
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    • 2016
  • Objective : The purpose of this study was to figure out the radiologic findings and risk factors related to adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF) using 3-year follow-up radiography, computed tomography (CT), and magnetic resonance image (MRI). Methods : A retrospective matched comparative study was performed for 64 patients who underwent single-level ACDF with a cage and plate. Radiologic parameters, including upper segment range of motion (USROM), lower segment range of motion (LSROM), upper segment disc height (UDH), and lower segment disc height (LDH), clinical outcomes assessed with neck and arm visual analogue scale (VAS), and risk factors were analyzed. Results : Patients were categorized into the ASD (32 patients) and non-ASD (32 patients) group. The decrease of UDH was significantly greater in the ASD group at each follow-up visit. At 36 months postoperatively, the difference for USROM value from the preoperative one significantly increased in the ASD group than non-ASD group. Preoperative other segment degeneration was significantly associated with the increased incidence of ASD at 36 months. However, pain intensity for the neck and arm was not significantly different between groups at any post-operative follow-up visit. Conclusion : The main factor affecting ASD is preoperative other segment degeneration out of the adjacent segment. In addition, patients over the age of 50 are at higher risk of developing ASD. Although there was definite radiologic degeneration in the ASD group, no significant difference was observed between the ASD and non-ASD groups in terms of the incidence of symptomatic disease.

Development of Full Segment Digital Broadcast Receiver based on the ISDB-T (ISDB-T 기반의 FULL-SEG 방송 수신 장치 개발)

  • Ohm, Woo-Yong
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.1
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    • pp.139-146
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    • 2017
  • The ISDB-T(Integrated Service Digital Broadcasting Terrestrial) can be used in the multipath and impulsive noise, also it provide good performance over mobile reception environment since it use the OFDM(Orthogonal Frequency Division Multiplexing) based transmission technology and time interleaving technology. One segment and full segment are divided according to the number of the assigned segment. And one-segment broadcasting receiver can design and implement without high levels of technology than the full-segment broadcasting receiver using 64QAM(64 Quadrature Amplitude Modulation) since it uses QPSK(Quadrature Phase Shift Keying) modulation/demodulation. However, it has a constraint in the display size and resolution due to data-rate limits. In this paper, we design and implementation of full-segment ISDB-T receiver module which support HD resolution for set-top box, digital TV, navigation. In experimental results, the implemented full-segment ISDB-T receiver module was satisfactory for all of the desired functions.

An Immunohistochemical study of the gastro-entero-pancreatic endocrine cells in the alimentary tract and the pancreas of the fresh water turtle, Geoclemys reevesii (남생이 위장관 및 췌장 내분비세포에 관한 면역조직화학적 연구)

  • Kim, Jong-beom;Lee, Jae-hyun
    • Korean Journal of Veterinary Research
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    • v.32 no.3
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    • pp.321-331
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    • 1992
  • The regional distribution and relative frequency of gastrointestinal endocrine cells were studied immunohistochemically in the gastrointestinal mucosa and pancreas of the fresh water turtle. Ten kinds of endocrine cells were identified in the gastrointestinal tract. Cholecystokinin-8-, bovine pancreatic polypetide-and glucagon-immunoreactive cells were seen throughout the gastrointestinal tract, also among them cholecystokinin-8-immunoreactive cells were most predominant in segment III. Although gastrin- and gastrin/cholecystokinin-immunoreactive cells were found from segment III to VI and X, respectively, they were numerous in segment III. Somatostatin-immunoreactive cells were observed from segment I to VII. 5-hydroxytryptamine- immunoreactive cells were detected in segment I, III, VIII, IX and X. Human pancreatic polypeptide-immunoreactive cells were demonstrated in segment V, VI, VIII, IX and X. Insulin-immunoreactive cells were found from segment III to X except for segment VIII, but rare in segment VII. Neurotensin-immunoreactive cells were found to be restricted to segment VIII, IX and X. No porcine chromogranin-, substance P- and bombesin-immunoreactive cells were detected throughout the gastrointestinal tract of the fresh water turtle. Although typical mammalian pancreatic islets encapsulated by connective tissue were not present in this species, five kinds of endocrine cells-glucagon, insulin, somatostatin, bovine pancreatic polypeptide and 5-hydroxytryptamine-were found in forming small or large groups and scattered in the exocrine gland region. However porcine chromogranin- and motilin-immunoreactive cells could not be demonstrated in the pancreas.

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Effect of Segment thickness during Shield TBM tunnelling in case study (쉴드TBM 추진시 세그먼트 두께영향에 대한 현장사례연구)

  • Kim, Sang-Hwan;Kim, Won-Kyung;Lee, Hye-Yoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.3
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    • pp.311-320
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    • 2013
  • This paper presents the effect of Segment thickness during Shield TBM tunnelling in case study. In order to perform this study, the ground condition developed in the investigation site are reviewed and analysed. It is also carried out the construction problems occurred in the site during Shield TBM tunnelling. Several Segments were broken partially during advance tunnel by jacking pressure. The data surveyed from site are analysed in order to investigate the cause of Segment break. The numerical and analytical evaluations are carried out to examine the effect of Segment behaviour. From the results, it is found that the main causes of Segment break may be the jacking system and Segment thickness. In addition, new jacking technique is suggested to install safely the Segment during advance tunnel by jacking.

Influence of the joint stiffness on the segment design (이음부 강성계수가 세그먼트 설계에 미치는 영향)

  • Choi, Woo-Yong;Park, Jong-Deok;Lee, Seok-Won
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.1
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    • pp.63-74
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    • 2014
  • The lining of shield TBM tunnel is composed of segments, therefore segment joints are induced by connecting each segment. Segment joint is considered as joint stiffness in the design of TBM tunnel. Depending on the choice among the different stiffness equations, the joint stiffness values determined can be varied largely. Therefore, the influence of joint stiffness value on the design of segment lining should be verified. In this study, the joint stiffness values were determined firstly by using various equations and total change boundary was justified. Within the change boundary determined, the member forces were calculated by changing the joint stiffness through the numerical analysis and consequently the stability of segment lining was investigated by applying nominal strength. The results showed that the segment joint stiffness did not affect the design of segment lining largely.

Estimation of Gamut Boundary based on Modified Segment Maxima to Reduce Color Artifacts (컬러 결점을 줄이기 위한 수정된 segment maxima 기반의 색역 추정)

  • Ha, Ho-Gun;Jang, In-Su;Lee, Tae-Hyoung;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.3
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    • pp.99-105
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    • 2011
  • In this paper, we proposed a method for estimating an accurate gamut based on segment maxima method. According to the number of segments in the segment maxima, a local concavity is generated in the vicinity of lightness axis or a gamut is reduced in high chroma region. It induces artifacts or deterioration of the image quality. To remove these artifacts, the number of segment is determined according to the number of samples. and a local concavity is modified by extending a detected concave point to the line connecting two adjacent boundary points. Experimental results show that the contours in a uniform color region and speckle artifacts from the conventional segment maxima algorithm are removed.