• Title/Summary/Keyword: Hold

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다목적실용위성 1호 Maneuver Mode에서의 지상관제 DATA 분석

  • Suk, Byong-Suk
    • Aerospace Engineering and Technology
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    • v.1 no.1
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    • pp.65-71
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    • 2002
  • KOMPSAT-1 AOCS mode divided into three major mode like Sun, Maneuver, Science Mode. The Maneuver mode consist of attitude hold and Δ-V Burn submode. This paper focus on the analysis of AOCS Maneuver Mode characteristics based on on-orbit playback data. The nadir pointing performance of attitude hold submode and the process for Δ-V Burn firing with plus/ minus 90 degree pitch/ roll maneuvering was verified. And also verified that the on-orbit performance meets the AOCS subsystem specification as designed.

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A PLL with an unipolar charge pump and a loop filter consisting of sample-hold capacitor and 2nd-order RC filter (2차-RC 필터와 Sample-Hold 커패시터로 구성된 루프 필터와 단방향 전하펌프를 가진 PLL)

  • Baek, Seung-Ha;Choi, Young-Shig
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.10
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    • pp.2380-2386
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    • 2013
  • A PLL with an unipolar charge pump and a loop filter consisting of sample-hold capacitor and 2nd-order RC filter has been proposed. The goal of the proposed PLL is the suppression of reference spur which is caused by charge pump mismatch. It also improves phase noise characteristic. It has been designed with a 1.8V $0.18{\mu}m$ CMOS process and proved by HSPICE simulation.

Heat Load Characteristics of Sea Water Cooling Apparatus on Inshore Fishing Boat (연근해 어선용 해수냉각장치의 열부하특성)

  • 한인근;문춘근;김재돌;윤정인
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1317-1323
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    • 2001
  • The circumstance is giving the blow against fishermen with the incoming-decreasing and the difficulty of crew's supply & demand and management. In addition, the depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. First of all, we Investigated load characteristics which based on development of sea water cooling system and optimum fish hold storage. The experimental results is as follows. In creasing the speed of compressor and mass blew rate of refrigerant, the temperature of NaCl solution is low. And the load characteristics experiment on fish hold storage outlet is as fellows. As time goes by, increasing the mass flow rate of NaCl solution, temperature difference between inlet and outlet is small in a model of fish hold storage. These results provide many useful informations applicable to an actual design of sea water cooling system and optimum fish hold storage.

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A Study on the Ship Cargo Hold Structure Data Model Based on STEP (STEP을 근거로 한 선체화물창부 구조 데이터 모델에 관한 연구)

  • 박광필;이규열;조두연
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.4
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    • pp.381-390
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    • 1999
  • In this study, a pseudo ship structure data model for the :.hip cargo hold structure based on STEP is proposed. The proposed data model is based on Application Reference Model of AP218 Ship Structure which is the model that specifies conceptual structures and constraints used to describe the information requirements of an application. And the proposeddata model refers the Ship Common Model framework for the model architecture which is the basis for ongoing ship AP development within the ISO ship-building group and the ship product definition information model of CSDP research project for analyzing the relationship between ship structure model entities. The proposed data model includes Space, Compartment. Ship Structural System, Structural Part and Structural Feature of cargo hold. To generate this data model schema in EXPRESS format, ‘GX-Converter’was used which enables user to edit a model in EXPRESS format and convert schema file in EXPRESS format. Using this model schema, STEP physical file containing design data for ship cargo hold data structure was generated through SDAI programming. The another STEP physical file was also generated containing geometry data of ship cargo hold which was extracted and calculated by SDAI and external surface/surface intersection program. The geometry information of ship cargo hold can be then transferred to commercial CAD system, for example, Pro/Engineer. Examples of the modification of the design information are also Presented.

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Effects on Frozen Shoulder as Seen in the Comparison Hold-Relax Technique and ROM Exercise (동결견 환자에 대한 정지-이완기법과 관절가동범위 운동의 비교)

  • Kim Soo-Min;Lee Hyun-Ock;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.7 no.1
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    • pp.51-59
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    • 1995
  • The purpose of this study is to evaluate pain and range of motion in the frozen shoulder and to compare Hold-Relax technique with ROM exercise. Twenty-eight frozen shoulder patients between 41 nod 76 years of age were selected and were divided equally by random distribution into a Hold-Relax technique group and a ROM exercise group. To analyze the therapeutic effect between the two groups, two measurements were taken. A measurement of pain was taken by visual analogue scale and a measurement of range of motion was taken by measuring flexion and abduction degrees with a goniometer. The results were as followings : 1. The Hold-Relax group is more effective in decreasing the pain than the ROM exercise group. 2. The Hold-Relax group is more effective in increasing the range of flexion at the shoulder than the ROM exercise group. 3. The Hold-Relax group is more effective in increasing the range of abduction at the shoulder than the ROM exercise group.

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The Effects on Flexion-Extension Craniocervical Joint by Proprioceptive Neuromuscular Facilitation with Hold-Relax Technique (고유수용성 신경근 촉진법 굴곡 신전 패턴이 두경부에 미치는 영향)

  • Jeon, Ho-Young;Jung, Hyun-Sung;Bae, Sung-Soo
    • PNF and Movement
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    • v.4 no.1
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    • pp.63-69
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    • 2006
  • Purpose : To identify the effects of Hold-Relax of proprioceptive neuromuscular facilitation (PNF) on the functional improvement of patients with neck myofascial pain syndrome. Methods : The present research investigated 30 patients with neck myofascial syndrome, dividing them into a group doing Hold-Relax of proprioceptive neuromuscular facilitation. This study examined degree of recovery from neck pain by comparing their neck myofascial pain syndrome before and after the treatment, and compared to find difference in the degree of recovery from myofascial pain syndrome. Results : The results are as follows. For the Hold-Relax of proprioceptive neuromuscular facilitation(PNF), the visual analogue scale(VAS) decreased significantly for six weeks treatment, and the range of motion(ROM) of cervical vertebrae increased significantly(p<.05). Conlusion : This study suggest that Hold-Relax of proprioceptive neuromuscular facilitation have an effect on the functional improvement of patients with neck myofascial pain syndrome.

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Injunctions and Hold-up under Weak Patent Protection

  • SIM, KYOUNGBO
    • KDI Journal of Economic Policy
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    • v.42 no.2
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    • pp.1-30
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    • 2020
  • This paper analyzes how injunctions relate to patent hold-up problems. To this end, we present a simple model of licensing negotiations between a patent holder and a downstream firm in the shadow of litigation. More specifically, we consider the situation in which an injunction is granted as a matter of course if a patent is found valid and infringed upon in litigation, but the patent holder may be under-compensated due to aspects of the patent remedy system other than injunctions. We show that if the downstream user is unaware of the patent before any investment in initially designing its product, the patent hold-up problems created by injunction threats are worrisome when (i) the redesign process is costly, (ii) the degree of patent protection (by aspects of the patent remedy system other than injunctions) is sufficiently strong and (iii) the injunction is requested not to practice the patented technology exclusively but to collect excessive patent royalties. Even if the downstream user is aware of the patent before the initial investment, the patent hold-up problems do not disappear. The findings here imply that a discretionary approach is required towards denying injunctions against patent infringement. If the degree of patent protection is not sufficiently strong, denying injunctions can exacerbate the under-compensation problem. However, once patent protection improves enough (not necessarily perfectly), we may see a surge of patent hold-up problems, and it would be better to apply alternative patent remedies in place of injunctions when necessary. Lastly, we discuss several possible alternatives to injunctions and their pros and cons.

Thermal-Mechanical and Low Cycle Fatigue Characteristics of 12Cr Heat Resisting Steel with Hold Time Effects (유지시간 효과를 고려한 12Cr 내열강의 열피로 및 저주기 피로 특성)

  • Ha, J.S.;Koh, S.K.;Ong, J.W.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.1
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    • pp.1-12
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    • 1995
  • Isothermal and thermal-mechanical fatigue characteristics of 12Cr heat resisting steel used for high temperature applications were investigated including hold time effects. Isothermal low cycle fatigue test at $600^{\circ}C$ and in-phase, out-of-phase thermal-mechanical fatigue test at 350 to $600^{\circ}C$ were conducted using smooth cylindrical hollow specimen under strain-control with total strain ranges from 0.006 to 0.015. Regardless of thermal-mechanical and isothermal fatigue tests, cyclic softening behavior was observed and much more pronounced in the thermal-mechanical fatigue tests with hold times due to the stress relaxation during the hold time. The phase difference between temperature and strain in thermal-mechanical fatigue tests resulted in significantly shorter fatigue life for out-of-phase compared to in-phase. The differences in fatigue lives were dependent upon the magnitudes of plastic strain ranges and mean stresses. During the hold time in the strain-controlled fatigue tests, the increase in the plastic strain range and the stress relaxation were observed. It appeared that the increase in plastic strain range per cycle and the introduction of creep damage made important contributions to the reduction of thermal-mechanical fatigue life with hold time, and the life reduction tendency was more remarkable in the in-phase than in the out-of-phase thermal-mechanical fatigue. Isothermal fatigue tests performed under the combination of fast and slow strain rates at $600^{\circ}C$ showed that the fatigue life decreased as the strain rate and frequency decreased,especially for the low strain ranges.

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The Effects of Hold-Relax Technique and Mulligan's Straight Leg Raise with Traction Technique on Flexibility of Shortened Hamstring (유지-이완 기법과 멀리건의 견인을 동반한 뻗은다리올림 기법이 단축된 넙다리뒤근의 유연성에 미치는 영향)

  • Choi, Yul-jung;Sim, Hyun-po;Lee, Jun-yong
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.21 no.1
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    • pp.5-11
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    • 2015
  • Background: The purpose of this study was to investigate the effects of Mulligan's straight leg raise with traction technique and hold-relax technique on flexibility of hamstring in people with shortened hamstring. Methods: Thirty two subjects participated in this study. The subjects were assigned to either the Mulligan's straight leg raise with traction technique group (n=16) or the hold-relax technique group (n=16). 90-90 straight leg raise test was performed for evaluation of hamstring shortening at initial time of study. After intervention, immediate effect (immediately after intervention) and lasted effect (60 min after intervention) were assessed. Results: In the both Mulligan's straight leg raise with traction technique and hold-relax technique groups, significant improvements on flexibility of hamstring was observed in immediately and 60 minute after intervention (p<.05). However, there are no significant difference was observed between groups (p>.05). Conclusion: In the results of this study, both Mulligan's straight leg raise with traction technique and hold-relax technique show immediately and 60 minute after evaluation effectiveness in flexibility of hamstring of people with shortened hamstring. In addition, although the difference is not statistically significant, Mulligan's straight leg raise with traction technique was more increased average extension angle of knee joint at 90-90 straight leg raise test than the hold-relax technique.

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Structural Strength and Fatigue Strength Assessment for Fore/Aft Cargo Hold of 60m Beam VLCC (60m Beam VLCC Fore/Aft Cargo Hold에 대한 구조 안정성 및 피로강도 평가)

  • Lee Sang-Woo;Choi J.H.;Kim M.S.;Kim M.S.;Lee Y.M.;Kim K.S.
    • Special Issue of the Society of Naval Architects of Korea
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    • 2005.06a
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    • pp.84-89
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    • 2005
  • The double hull VLCC(Very Large Crude Oil Tanker) have been designed to have each four(4) longitudinal bulkheads and transverse bulkheads in general. Actually, the inside longitudinal bulkheads among four(4) longitudinal bulkheads, which are extended up to the end of the aft cargo hold for continuity of the members, have been designed with knuckled type inboard due to the narrowed hull shape at bottom region, but sometimes the straight type of longitudinal bulkheads were adopted based on the degree of the hull lines shape. However, regardless the type of longitudinal bulkheads, inside and outside longitudinal bulkheads conflict each other in aft cargo hold region This makes the structure more complex thus giving difficulties to structural design and production. Recently, a vessel of straight type was reported to have cracks on bracket end and tripping bracket toe in aft cargo hold region. As a solution to this problem, in designing the first 60m Beam VLCC, DSME developed a new cargo hold structure which is good in production and structural point of view by structural strength and fatigue analysis of fore and aft cargo hold.

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