• Title/Summary/Keyword: J hook

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Comparison of circle hook and J hook catch rate for target and bycatch species taken in the Korean tuna longline fishery

  • Kim, Soon-Song;Moon, Dae-Yeon;Boggs, Christofer;Koh, Jeong-Rack;An, Doo-Hae
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.4
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    • pp.210-216
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    • 2006
  • The circle hook experiments were conducted to compare the catch rates of target and bycatch species between J hook and circle hooks in the tuna longline fishery of the eastern Pacific Ocean between $1^{\circ}48'S-7^{\circ}00'S\;and\;142^{\circ}00'-149^{\circ}13'W$ from July 15 to August 12, 2005. In the target species group no significant differences among 3 types hook, between size 4.0 traditional tuna hooks(J-4) and size 15 circle hooks(C15), and between C15 and size 18 circle hooks(C18) were revealed, but significant differences were found between J-4 and C18. In the bycatch species group significant differences were found among 3 types hook, between J 4 and C15, and between J-4 and C18, but no significant differences were revealed between C15 and C18. Large circle hook(C18) had the lowest catch rate for tunas and for other fishes, and the small circle hook(C15) had lowest rate for billfishes and sharks. The length distributions for bigeye tuna are very similar for the 3 hook types. There were very slight differences in length size between hook types in the bycatch species.

Numerical studies of steel-concrete-steel sandwich walls with J-hook connectors subjected to axial loads

  • Huang, Zhenyu;Liew, J.Y. Richard
    • Steel and Composite Structures
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    • v.21 no.3
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    • pp.461-477
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    • 2016
  • Steel-concrete-steel (SCS) sandwich composite wall has been proposed for building and offshore constructions. An ultra-lightweight cement composite with density1380 kg/m3 and compressive strength up to 60 MPa is used as core material and inter-locking J-hook connectors are welded on the steel face plates to achieve the composite action. This paper presents the numerical models using nonlinear finite element analysis to investigate the load displacement behavior of SCS sandwich walls subjected to axial compression. The results obtained from finite element analysis are verified against the test results to establish its accuracy in predicting load-displacement curves, maximum resistance and failure modes of the sandwich walls. The studies show that the inter-locking J-hook connectors are subjected to tension force due to the lateral expansion of cement composite core under compression. This signifies the important role of the interlocking effect of J-hook connectors in preventing tensile separation of the steel face plates so that the local buckling of steel face plates is prevented.

A cephalometric evaluation of anterior j hook headgear traction to the maxilla (Anterior j hook headgear를 이용한 상악골 성장억제에 관한 연구)

  • Chung, Kyu-Rhim;Kang, Jang-Yun
    • The korean journal of orthodontics
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    • v.30 no.4 s.81
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    • pp.387-398
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    • 2000
  • This study was aimed to observe the effect of Anterior J hook headgear on the craniofacial structures in mixed dentition with Class II malocclusion. The laterial cephalograms of 20 children treated by Anterior J hook headgear were traced, digitized and statistically analyzed. The results were as follows : 1. Forward growth of maxilla was inhibited. 2. Rotational effect of maxilla was not observed. 3. There was distal movement of maxillary dentition. 4. Maxillarly_dentoalveolar growth changes were more effective in anterior portion than posterior portion. 5. Mandible maintained a normal growth and mandibular plane angle was maintained during treatment period. 6. The ratio of anterior facial height to posterior facial height was almostly not changed.

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A PHOTOELASTIC STUDY ON THE STRESS DISTRIBUTION OF THE UPPER ANTERIOR TEETH WHEN RETRACT WITH HIGH PULL J-HOOK HEADGEAR (상악전치의 후방견인시 J-hook headgear의 사용이 응력분포변화에 미치는 영향에 대한 광탄성학적 연구)

  • Lee, You-Jin;Park, Soo-Byung
    • The korean journal of orthodontics
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    • v.27 no.5 s.64
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    • pp.697-709
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    • 1997
  • This study was designed to investigate the stress intensity and distribution produced by 1mm activation of retraction archwire with $0^{\circ},\;7^{\circ},\;14^{\circ}$ torque and application of high polk J-hook headgear during retraction of four maxillary incisors using the photoelastic stress analysis. The photoelastic model was made with a PL-3 type epoxy resin which was substituted by alveolar bone portion. Each retraction archwire was fabricated from .020' X .025' stainless steel wire which had vertical loops in 7mm height and hooks for high pull J-hook headgear between central and lateral incisors. The high pull J-hook headgear was applied 35 degree backward and upward to occlusal plane with 200gm pet each side The findings of this study were as follows: 1. In case of $0^{\circ}$ torque, the stress was distributed from cervical 1/8 to apex of roots of central and lateral incisors which were the forms of arc mode. When the high pull J-hook headgear was applied, the stress distributed by arc mode was presented from cervical 1/2 to apex of roots of central and lateral incisors. And the stress distributed by following the root surface was presented from alveolar crest to cervical 1/2 of roots of central and lateral incisors. The stress between apecies of central and Lateral incisors was presented also. 2. In case of $7^{\circ}$ torque, the stress distributed by arc mode was presented from cervical 1/2 to apex of roots of central and lateral incisors. And the stress distributed by following the root surface was presented from alveolar crest to cervical 1/2 of roots of central and lateral incisors. When the high pull J-hook headgear was applied, the stress distributed by following the root surface was presented mote apically than without headgear. The stress between apecies of central and lateral incisors was presented also. 3. In case of $14^{\circ}$ torque, the stress distributed by following the root surface was Presented from alveolar crest to apex of roots of central and lateral incisors. When the high pull J-hook headgear was applied, the stress distributed by following the root surface was presented stronger than without headgear The stress between apecies of central and lateral incisors was presented also.

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A PHOTOELASTIC STUDY ON THE INITIAL STRESS DISTRIBUTION OF THE UPPER ANTERIOR TEETH WHEN INTRUSIVE FORCE APPLIED (BY UTILITY ARCHWIRE, BURSTONE INTRUSION ARCHWIRE, and 'J' HOOK HEADGEAR) (상악 전치부 INTRUSION시 초기 응력 분포에 관한 광탄성학적 분석(Utility archwire Burstone intrusion archwire, 'J'hook headgear에 의한))

  • Baik, Hye-Jong;Baik, Hyoung-Seon
    • The korean journal of orthodontics
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    • v.27 no.3 s.62
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    • pp.401-409
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    • 1997
  • The purpose of this study was to analize the initial stress distribution around apex and the alveolar bone of the upper anterior teeth when applying intrusive force by the use of utility arthwire, Burstono 3-piece infusion archwire, and 'J' hook headgear which is usually used in clinital practice. By the use of the polarization plate, initial stresses were analized when 80g and 150g forte applied. The results were as follows. 1. With the utility archwire, moderate levels of stress were evenly distributed on the apical areas of the anterior teeth and concentrated on the apical areas of the first molars. 2. With the Burstone's 3-piece intrusion archwire, moderate levels of stress were evenly distributed on the apical areas of the anterior and posterior teeth. 3. With the 'J' hook headgear, severe levels oi stress were widely distributed on the alveolar bone and apical areas of the upper anterior teeth, and concentrated on the apical area between the central and the lateral incisors. Especially, weak levels of stress appeared along the periodontal ligament space of all teeth.

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Development of a Hook-type Finger Force Measuring System with Force Sensors (힘센서를 이용한 후크형 손가락 힘 측정 장치 개발)

  • Kim, Gab-Soon
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.6
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    • pp.663-668
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    • 2014
  • This paper presents a hook-type finger force measuring system with force sensors. The system is composed of a body, two three-axis force sensors, a hook, and so on. The two three-axis force sensors system was specially designed using FEM(Finite Element Method) and fabricated using strain-gages. The sensors measure the finger forces of both normal people and handicapped people in the system, and the forces are combined. The developed hook-type finger force measuring system can measure the pulling finger force of both normal and handicapped people. The pulling force tests of men and women were performed using the developed the system. It is thought that the developed system can be used to measure the pulling force of fingers.

A Study on Applicability of RFID System for C-Hook Identification (C-Hook 인식을 위한 RFID 시스템의 적용 가능성에 대한 연구)

  • Lee, Chang-Woo;Cho, Hyeon-Woo;Ban, Sung-Jun;Kwon, Yong-Sin;Kim, Sang-Woo
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.1
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    • pp.81-87
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    • 2008
  • C-Hook is a kind of conveyer system for transporting steel coil in POSCO. To detect the current position and the trajectory of steel coils in a plant, C-Hooks are tracked by an inspection system based on PLC. The inspection system detects transit of C-Hooks by monitoring a physical contact between steel bars on a C-Hook and the inspection sensors. However, this system is not reliable because of the abrasion, damage and aging. Moreover, the number of distinguishable C-Hooks is limited by the number of combination of steel bars on a C-Hook. It means that more steel bars should be installed for distinguishing the more C-Hooks. Therefore, the conventional system is difficult and expensive to maintain. To overcome these problems, we propose a C-Hook identification system that uses RFID which is a non-contact type identification system, and evaluate its performance and applicability from a new monitoring program that operates along with the conventional system in the real environment of POSCO.

Ultimate strength behavior of steel-concrete-steel sandwich beams with ultra-lightweight cement composite, Part 2: Finite element analysis

  • Yan, Jia-Bao;Liew, J.Y. Richard;Zhang, Min-Hong
    • Steel and Composite Structures
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    • v.18 no.4
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    • pp.1001-1021
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    • 2015
  • Ultra-lightweight cement composite (ULCC) with a compressive strength of 60 MPa and density of $1,450kg/m^3$ has been developed and used in the steel-concrete-steel (SCS) sandwich structures. This paper investigates the structural performances of SCS sandwich composite beams with ULCC as filled material. Overlapped headed shear studs were used to provide shear and tensile bond between the face plate and the lightweight core. Three-dimensional nonlinear finite element (FE) model was developed for the ultimate strength analysis of such SCS sandwich composite beams. The accuracy of the FE analysis was established by comparing the predicted results with the quasi-static tests on the SCS sandwich beams. The FE model was also applied to the nonlinear analysis on curved SCS sandwich beam and shells and the SCS sandwich beams with J-hook connectors and different concrete core including ULCC, lightweight concrete (LWC) and normal weight concrete (NWC). Validations were also carried out to check the accuracy of the FE analysis on the SCS sandwich beams with J-hook connectors and curved SCS sandwich structure. Finally, recommended FE analysis procedures were given.