• Title/Summary/Keyword: anchor point

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Computer Simulation for Working Condition of Undergroundwork Using TOP DOWN Technique (TOP DOWN 지하공사의 작업환경체크 컴퓨터시물레이션에 관한 기초적 연구)

  • 고성석;손기상;심경수
    • Journal of the Korean Society of Safety
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    • v.10 no.3
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    • pp.96-105
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    • 1995
  • The better industry develops, the more spaces need but in the limited area. Most building become larger and more complicated if the more spaces need in the constant area. And this leads to do underground work in long period generally six(6) months for 6 basement stories due to the selection of TOP DOWN technique. Working environment in this underground area can be problems and should not be overlooked, because air quality in underground spaces become quickly worse. Recently, department name to control construction safety has been changed to ENVIRONMENT & SAFETY TEAM from SAFETY TEAM. This means that it is very important to control against environmental condition at site so much. Overall construction work as well as underground work should conform to the requirement of working environment, particularly against inhabitants around the construction area. Strut protection, one of earth protection method, in case to 40m long strut may become weaker due to thermal stress or its longitudinally compressive strain and the another one, earth anchor protection may not be applied to the site In case of encroaching on vertical underground borderline because of regulation to prohibit it. It is necessary that TOP DOWN technique should be introduced in order to solve the external and internal problem of the site such as difficulty level of the work, potential danger with excavating depth, and shortening workperiod. It is needed that improving way of working condition should be shown and simplified computer simulation program should be also provided for checking pollution level & ventilation, excluding of lighting problem here. Results measured with conformance to the Regulation for Working Environment Measurement, enforced by Ministry of Labor have been applied to the computer program developed here. Sample air taken at unit workplace which was considered as exposing condition of pollutant at breathing point and within a range of behavior of the workers, Identified exposing group in underground work, using Moded Flow Life Finally, three types of ventilation system, type I with blower & ventilator, type II natural supply with mechanical ventilation system, and type I mechanical ventilation with Drivent Fan Unit System are selected for this study.

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A Design of Mooring Line for the Buoy-Enabled Underwater Surveillance System (부이형 수중감시 시스템에서 계류라인의 구조 설계)

  • Byun, Yang-Hun;Choi, Bum-Kyu;Oh, Tae-Won
    • The Journal of Korean Institute of Information Technology
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    • v.16 no.12
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    • pp.41-47
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    • 2018
  • The buoy-enabled underwater surveillance system is a device that is installed in a particular sea area and operated for a certain period of tine and moved to another sea area after recovery. In this paper, a mooring method which is applied for a buoy-enabled underwater surveillance system was selected to maintain installation and enure stable operation. Also, the structure of the mooring line was designed. Two-point mooring method was selected considering interference with the communication cable of array-assembly. The composite structure of buoy chain, nylon rope, and anchor chain is designed as the basic component of mooring line. For the verification of design, a numerical simulation and wave tank experiment were performed. Their results were confirmed similarity in test condition. Finally, the mooring lines were designed for the environment of the sea trial location. The mooring line produced by the final design confirmed the stability above the significant wave height considered in the design on the sea trial.

Historiography of TV Documentary (TV의 젠더 역사쓰기의 가능성과 한계: 역사다큐멘터리를 중심으로)

  • Kim, Hoon-Soon;Kim, Suk
    • Korean journal of communication and information
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    • v.51
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    • pp.156-173
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    • 2010
  • This study analysed the narrative of and , two history documentary broadcasted on KBS, in terms of story-telling and discourse. And it also examined whether TV as mass media could provide an alternative interpretation against the dominant historical awareness. As a result, both programmes showed limitations on representing subversive point of view to the dominant ideology. At the story-telling level, firstly, they represented in a way of male-hero narrative though they were describing the history of woman, and while representing woman as a public figure they eliminated her feminity and individuality. Secondly, before evaluating woman as a historic figure they previously appreciated her appearance in a male-point of view. Thirdly, although they were telling the story of woman in a political view, they focused on love triangle, therefore failed to make her as a public figure. The discourses of both programmes were anchoring the existing historical interpretation instead of offering an alternative historical imagination. The narrator who were telling history at the studio in a omniscient viewpoint took a role as a meaning definer, placed at the highest rank in the hierarchy of discourse structure. Especially in , the dramatized images to cover lack of visual data helped anchor the patriarchal narrative and reduced the possibility of subversive interpretation on historic figure.

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The hydrodynamic characteristics of the canvas kite - 2. The characteristics of the triangular canvas kite - (캔버스 카이트의 유체역학적 특성에 관한 연구 - 2. 삼각형 캔버스 카이트의 특성 -)

  • Bae, Bong-Seong;Bae, Jae-Hyun;An, Heui-Chun;Lee, Ju-Hee;Shin, Jung-Wook
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.40 no.3
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    • pp.206-213
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    • 2004
  • As far as an opening device of fishing gears is concerned, applications of a kite are under development around the world. The typical examples are found in the opening device of the stow net on anchor and the buoyancy material of the trawl. While the stow net on anchor has proved its capability for the past 20 years, the trawl has not been wildly used since it has been first introduced for the commercial use only without sufficient studies and thus has revealed many drawbacks. Therefore, the fundamental hydrodynamics of the kite itself need to ne studied further. Models of plate and canvas kite were deployed in the circulating water tank for the mechanical test. For this situation lift and drag tests were performed considering a change in the shape of objects, which resulted in a different aspect ratio of rectangle and trapezoid. The results obtained from the above approaches are summarized as follows, where aspect ratio, attack angle, lift coefficient and maximum lift coefficient are denoted as A, B, $C_L$ and $C_{Lmax}$ respectively : 1. Given the triangular plate, $C_{Lmax}$ was produced as 1.26${\sim}$1.32 with A${\leq}$1 and 38$^{\circ}$B${\leq}$42$^{\circ}$. And when A${\geq}$1.5 and 20$^{\circ}$${\leq}$B${\leq}$50$^{\circ}$, $C_L$ was around 0.85. Given the inverted triangular plate, $C_{Lmax}$ was 1.46${\sim}$1.56 with A${\leq}$1 and 36$^{\circ}$B${\leq}$38$^{\circ}$. And When A${\geq}$1.5 and 22$^{\circ}$B${\leq}$26$^{\circ}$, $C_{Lmax}$ was 1.05${\sim}$1.21. Given the triangular kite, $C_{Lmax}$ was produced as 1.67${\sim}$1.77 with A${\leq}$1 and 46$^{\circ}$B${\leq}$48$^{\circ}$. And when A${\geq}$1.5 and 20$^{\circ}$B${\leq}$50$^{\circ}$, $C_L$ was around 1.10. Given the inverted triangular kite, $C_{Lmax}$ was 1.44${\sim}$1.68 with A${\leq}$1 and 28$^{\circ}$B${\leq}$32$^{\circ}$. And when A${\geq}$1.5 and 18$^{\circ}$B${\leq}$24$^{\circ}$, $C_{Lmax}$ was 1.03${\sim}$1.18. 2. For a model with A=1/2, an increase in B caused an increase in $C_L$ until $C_L$ has reached the maximum. Then there was a tendency of a very gradual decrease or no change in the value of $C_L$. For a model with A=2/3, the tendency of $C_L$ was similar to the case of a model with A=1/2. For a model with A=1, an increase in B caused an increase in $C_L$ until $C_L$ has reached the maximum. And the tendency of $C_L$ didn't change dramatically. For a model with A=1.5, the tendency of $C_L$ as a function of B was changed very small as 0.75${\sim}$1.22 with 20$^{\circ}$B${\leq}$50$^{\circ}$. For a model with A=2, the tendency of $C_L$ as a function of B was almost the same in the triangular model. There was no considerable change in the models with 20$^{\circ}$B${\leq}$50$^{\circ}$. 3. The inverted model's $C_L$ as a function of increase of B reached the maximum rapidly, then decreased gradually compared to the non-inverted models. Others were decreased dramatically. 4. The action point of dynamic pressure in accordance with the attack angle was close to the rear area of the model with small attack angle, and with large attack angle, the action point was close to the front part of the model. 5. There was camber vertex in the position in which the fluid pressure was generated, and the triangular canvas had large value of camber vertex when the aspect ratio was high, while the inverted triangular canvas was versa. 6. All canvas kite had larger camber ratio when the aspect ratio was high, and the triangular canvas had larger one when the attack angle was high, while the inverted triangluar canvas was versa.

Study on the Shear Strengthening of Concrete Beams with Wire Rope Clamped by Bolts (볼트 체결된 와이어 로프를 이용한 RC 보의 전단보강에 대한 연구)

  • Kim, Sun-Young;Song, Jin-Gyu;Lee, Young-Uk;Byun, Hang-Yong
    • Journal of the Korea Concrete Institute
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    • v.18 no.2 s.92
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    • pp.283-290
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    • 2006
  • The paper describes m experimental study on the shear strengthening of concrete beams with exposed wire rope. The strengthening method is using the mechanical bolting of wire rope tensioned on the exterior of beam section. There are two shear strengthening types. The first is closed type wrapped beam section with wire rope like as closed stirrup. The second is U type tensioned at the anchor located in the side of beam section. The main parameters of specimens are strengthening spacings of wire rope with 150, 200, and 250mm for the closed and U type respectively. The shear span ratio of specimens applied by 3-point loading is 4. The results showed that the ultimate shear strength and ductility of strengthened beams increased significantly compared with non-strengthened beams. Especially, the strengthening effect of closed type was very preferable to U type. Therefore, the shear strengthening method with wire rope is very reasonable in view of repair and rehabilitation of beams.

Properties and Utilization of Undigested Peptides in Anchovy Sauces 1. Use of Undigested Peptides as a Quality Parameter of Anchovy Sauces (멸치 액젓 중에 존재하는 미분해 펩티드의 특성과 이용 1. 미분해 펩티드를 이용한 멸치 액젓의 품질 지표 설정)

  • CHOI Young Joon;KIM Se-Hwan;IM Yeong-Sun;Kim In-Soo;KIM Dong-Su;CHO Young-Je
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.3
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    • pp.386-392
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    • 1998
  • An objective index for quality estimation of anchovy sauce, our traditional seafood, has been required because inadequate standard causes dispute about quality estimation. Qualities of anchovy sauce made by traditional method and commercial anchor sauce products were compared by investigating their proximate compositions, total nitrogen contents, amino acid contents, development and level of a specific peptide on SDS-polyacrylamde gel electrophoresis (SDS-PAGE) and isoelectric point (pI) of the specific peptide. Also, pIs of IEF were attemped to identify fish species of salt-fermented sauces. The 55,600 and 46,900 dalton of peptide band were identified in all experimental samples. Especially, the area of 55,600 dalton was closely correlated with total nitrogen contents. Also, specific pIs in accordance with fish species were identified. The results suggest that correlation between area of 55,600 dalton and total nitrogen contents are used of index for quality estimation, and specific pIs are used of fish species identification.

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Wireless LAN-based Vehicle Location Estimation in GPS Shading Environment (GPS 음영 환경에서 무선랜 기반 차량 위치 추정 연구)

  • Lee, Donghun;Min, Kyungin;Kim, Jungha
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.1
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    • pp.94-106
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    • 2020
  • Recently, the radio navigation method utilizing the GPS(Global Positioning System) satellite information is widely used as the method to measure the position of objects. As GPS applications become wider and fields based on various positioning information emerge, new methods for achieving higher accuracy are required. In the case of autonomous vehicles, the INS(Inertial Navigation System) using the IMU(Inertial Measurement Unit), and the DR(Dead Reckoning) algorithm using the in-vehicle sensor, are used for the purpose of preventing degradation of accuracy of the GPS and to measure the position in the shadow area. However, these positioning methods have many elements of problems due not only to the existence of various shaded areas such as building areas that are continually enlarged, tunnels, underground parking lots and but also to the limitations of accumulation-based location estimation methods that increase in error over time. In this paper, an efficient positioning method in a large underground parking space using Fingerprint method is proposed by placing the AP(Access Points) and directional antennas in the form of four anchors using WLAN, a popular means of wireless communication, for positioning the vehicle in the GPS shadow area. The proposed method is proved to be able to produce unchanged positioning results even in an environment where parked vehicles are moved as time passes.

Arthroscopic Rotator Cuff Repair: Serial comparison of outcomes between full-thickness rotator cuff tear and partial-thickness rotator cuff tear

  • Park, Jin-Young;Chung, Kyung-Tae;Yoo, Moon-Jib
    • Clinics in Shoulder and Elbow
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    • v.6 no.1
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    • pp.72-79
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    • 2003
  • Purpose: To compare the results of arthroscopic rotator cuff repair and subacromial decompression in partial thickness rotator cuff tear (PTRCT) with those in full thickness rotator cuff tear (FTRCT). Subjects and method: Of the 46 patients who were rested of the rotator cuff tear based on the operational findings, 42 patients who were able to receive a serial follow-up for 2 years were selected as the study subjects. The average age of the patients at the time of the operation was 55 years, and the mean duration of the follow-up was 34 months. The subjects included 22 cases of PTRCT and 20 cases of FTRCT. In terms of rotator cuff repair, the average number of tendon to tendon repair (TTR) was 1 in both PTRCT and FTRCT, and that of tendon to bone repair (TBR) was 1 and 3 in PTRCT and FTRCT, respectively. The average number of use of suture anchor was 1 and 2 in PTRCT and FTRCT, respectively. The level of shoulder pain and function of the subjects were measured using shoulder functional evaluation score of American shoulder and elbow society (ASES score) at before and 2 years following the operation. Results: At the final follow-up following the operation, PTRCT group showed changes in scores from 7.2 to 0.9 on average pain score and 34 to 91 on ASES score, whereas FTRCT group showed changes in scores from 7.6 to 1.2 on pain score and 29 to 88 on ASES score. There were no significant differences between the two groups (P > 0.05). The average range of motion of shoulder significantly increased in both groups at the final follow-up in comparison with the pre-operative time point. The evaluation at the final follow-up showed that 93% of the total subjects showed good or excellent results, and 95% showed satisfactory results from the procedure with regard to pain reduction and functional outcomes. Two cases of the 3 fair results were caused by acromioclavicular arthritis. Conclusion: It may be anticipated that arthroscopic rotator cuff repair and subacromial decompression may bring satisfactory post-operative outcomes in both PTRCT and FTRCT on pain relief and functional recovery. However, careful preoperative examination of the acromioclavicular joint is critical to avoid failures of these procedures.

Performance Analysis of Fast Handover Scheme Based on Secure Smart Mobility in PMIPv6 Networks (프록시 모바일 IPv6 네트워크에서 안전한 스마트 이동성에 기반한 빠른 핸드오버 기법의 성능분석)

  • Yoon, KyoungWon;Jeong, Jongpil
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.5
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    • pp.121-133
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    • 2013
  • Defect-free transfer service on the Next-generation wireless network extensive roaming mobile node (MN) to provide efficient mobility management has become very important. MIPv6(Mobility IPv6) is one of mobility management scheme proposed by IETF(Internet Engineering Task Force), and IPv6-based mobility management techniques have been developed in various forms. One of each management techniques, IPv6-based mobility management techniques for PMIPv6 (MIPv6) system to improve the performance of a variety of F-PMIPv6 (Fast Handover for Proxy MIPv6) is proposed. However, the F-PMIPv6 is cannot be excellent than PMIPv6 in all scenarios. Therefor, to select a proper mobility management scheme between PMIPv6 and F-PMIPv6 becomes an interesting issue, for its potenrials in enhancing the capacity and scalability of the system. In this paper, we develop an analytical model to analyze the applicability of PMIPv6 and F-PMIPv6. Based on this model, we design an Secure Smart Mobility Support(SSM) scheme that selects the better alternative between PMIPv6 and F-PMIPv6 for a user according to its changing mobility and service characteristics. When F-PMIPv6 is adopted, SSM chooses the best mobility anchor point and regional size to optimize the system performance. Numerical results illustrate the impact of some key parameters on the applicability of PMIPv6 and F-PMIPv6. Finally, SSM has proven even better result than PMIPv6 and F-PMIPv6.

An Adaptive Load Control Scheme in Hierarchical Mobile IPv6 Networks (계층적 모바일 IP 망에서의 적응형 부하 제어 기법)

  • Pack Sang heon;Kwon Tae kyoung;Choi Yang hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.10A
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    • pp.1131-1138
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    • 2004
  • In Hierarchical Mobile Ipv6 (HMIPv6) networks, the mobility anchor point (MAP) handles binding update (BU) procedures locally to reduce signaling overhead for mobility. However, as the number of mobile nodes (MNs) handled by the MAP increases, the MAP suffers from the overhead not only to handle signaling traffic but also to Process data tunneling traffic. Therefore, it is important to control the number of MNs serviced by the MAP, in order to mitigate the burden of the MAP. We propose an adaptive load control scheme, which consists of two sub-algorithms: threshold-based admission control algorithm and session-to-mobility ratio (SMR) based replacement algorithm. When the number of MNs at a MAP reaches to the full capacity, the MAP replaces an existing MN at the MAP, whose SMR is high, with an MN that just requests binding update. The replaced MN is redirected to its home agent. We analyze the proposed load control scheme using the .Markov chain model in terms of the new MN and the ongoing MN blocking probabilities. Numerical results indicate that the above probabilities are lowered significantly compared to the threshold-based admission control alone.