• Title/Summary/Keyword: Pool

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Analysis on the construction examples of patent pool in Telecommunications standardization activities (정보통신표준화와 관련된 특허POOL 구축사례분석)

  • 이상무;박기식
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.11a
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    • pp.53-59
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    • 1999
  • A Patent Pool tends to be activated to establish the harmonization in recently standardization activities related to information and telecommunications with patent rights. Recent main examples of patent pool related to telecommunications standardization are concentrated in this paper. We seem to examine the practical meanings of patent pool from review the examples of utilizing patent pool. Those examples are analyzed and presented in this paper as typical construction cases of patent pool by characteristic of formation : The MPEG-2 patent pool which has become a pioneering precedence being managed by establishing MPEG LA as professional and administrative entity having organizied scalef; DVD patent pool which is a type of dividied case of a patent pool; the patent pool of IEEE1394 which was formed by surronding technology market effect outside the entrepreneur; finally the UMTS case in mobile telecommunications area.

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Study on Legal Issues of Facility Management of Children's Swimming Pool

  • KWON, Yeon Taek;SEO, Myung Seok;SEO, Won Jae
    • Journal of Sport and Applied Science
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    • v.3 no.1
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    • pp.19-25
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    • 2019
  • Purpose: Children's swimming pools are picking up faster than the other types of swimming pool. Yet, safety law-related studies are still lack. This study is to review legal status of children's swimming pool in Korea and to discuss the related legal issues for safety management of children's swimming pool. Research design, data, and methodology: The study reviewed law and clauses for sport facility management and related legal clauses with chilren's swimming pool management, and sport facility-related articles. Results: Safety management of children's swimming pool should currently follow law for sport and physical education facility management because of no its own legal norm for children's swimming pool. Given this, specific law and clauses for children's pool management need to be legislated to prevent risks for children and to satisfy specific safety factors considering careless behavior of children. Conclusions: Regarding this, the study points out five suggestions. First, law should be established to make notification of safety rules mandatory and this notification should be placed in the pool. This notification would be better effective if it is visualized. Second, according to law, safety 7 rules of children' s swimming pool need to be legistrated and educated for pool managers to obey them. Pool managers could also add their own rules to the 7 rules. Finally, preparation of emergency kits and safety devices need to be mandatory in the pool. Further implications were discussed.

Effects of Surface Depression on Pool Convection and Oscillation in GTAW (GTA 용접에서 용융풀의 표면 변형이 유동과 진동에 미치는 영향)

  • 고성훈;최상균;유중돈
    • Journal of Welding and Joining
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    • v.17 no.6
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    • pp.70-77
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    • 1999
  • Surface depression in the arc welding is calculated numerically to analyze its influence on pool convection and oscillation. The magnitude of surface depression due to arc pressure on the stationary GTA pool surface is relatively small, and fluctuations of the surface and velocity are caused mainly by arc pressure. The inward flow on the surface due to the electromagnetic force and positive surface tension gradient acts to decrease surface depression. Surface depression appears to have minor effects on average flow velocity and thus pool geometry. Pool oscillation occurs due to surface vibration, and oscillation frequencies are affected mainly by the surface tension and pool width. The input parameters such as arc pressure and current have negligible effects on the oscillation frequency, and the surface tension gradient has limited effects. Since the oscillation frequency varies slightly according to penetration, pool oscillation for the partial penetration weld pool is applicable to monitor the pool width.

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A STUDY ON WELD POOL MONITORING IN PULSED LASER EDGE WELDING

  • Lee, Seung-Key;Na, Suck-Joo
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.595-599
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    • 2002
  • Edge welding of thin sheets is very difficult because of the fit-up problem and small weld area In laser welding, joint fit-up and penetration are critical for sound weld quality, which can be monitored by appropriate methods. Among the various monitoring systems, visual monitoring method is attractive because various kinds of weld pool information can be extracted directly. In this study, a vision sensor was adopted for the weld pool monitoring in pulsed Nd:YAG laser edge welding to monitor whether the penetration is enough and the joint fit-up is within the requirement. Pulsed Nd:YAG laser provides a series of periodic laser pulses, while the shape and brightness of the weld pool change temporally even in one pulse duration. The shutter-triggered and non-interlaced CCD camera was used to acquire a temporally changed weld pool image at the moment representing the weld status well. The information for quality monitoring can be extracted from the monitored weld pool image by an image processing algorithm. Weld pool image contains not only the information about the joint fit-up, but the penetration. The information about the joint fit-up can be extracted from the weld pool shape, and that about a penetration from the brightness. Weld pool parameters that represent the characteristics of the weld pool were selected based on the geometrical appearance and brightness profile. In order to achieve accurate prediction of the weld penetration, which is nonlinear model, neural network with the selected weld pool parameters was applied.

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Variability of Surface Chlorophyll Concentration in the Northwest Pacific Ocean (북서태평양의 표층엽록소 변동성)

  • Park, Ji-Soo;Suk, Moon-Sik;Yoon, Suk;Yoo, Sin-Jae
    • Ocean and Polar Research
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    • v.30 no.3
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    • pp.277-287
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    • 2008
  • We collected information on seasonal and interannual variability of surface chlorophyll a concentration between 1997-2007 from the Northwest Pacific Ocean. Satellite data were used to acquire chlorophyll a and sea surface temperature from six regions: East Sea/Ulleung Basin, East China Sea, Philippin Sea, Warm Pool region, Warm Pool North region, and Warm Pool East region. Mixed layer depth (MLD) was calculated from temperature profiles of ARGO floats data in four of the six regions during 2002-2007. In the East Sea/Ulleung Basin, seasonal variability of chlorophyll a concentration was attributed to seasonal change of MLD, while there was no significant relationship between chlorophyll a concentration and MLD in the Warm Pool region. Interannual anomaly in sea surface temperature were similar among the East Sea, East China Sea, Philippin Sea, and Warm Pool North region. The anomaly pattern was reversed in the Warm Pool East region. However, the anomaly pattern in the Warm Pool region was intermediate of the two patterns. In relation to chlorophyll a, there was a reversed interannual anomaly pattern between Warm Pool North and Warm Pool East, while the anomaly pattern in the Warm Pool region was similar to that of Warm Pool North except for the El $Ni\tilde{n}o$ years (1997/1998, 2002/2003, 2006/2007). However, there was no distinct relationship among other seas. Interestingly, in the Warm Pool and Warm Pool East regions, sea surface temperature showed a pronounced inverse pattern with chlorophyll a. This indicates a strong interrelationship among sea surface temperature-MLD-chlorophyll a in the regions. In the Warm Pool and Warm Pool East, zonal distribution of chlorophyll a concentration within the past 10 years has shown a good relationship with sea surface temperature which reflects ENSO variability.

Development of a Pool Cleaning Robot and its Cleaning Performance Evaluation (수영장 청소 로봇 개발 및 청소성능지표)

  • Kim, Jinhyuk;Kim, Jinhyun
    • The Journal of Korea Robotics Society
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    • v.7 no.4
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    • pp.243-251
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    • 2012
  • In this paper, developing of a pool cleaning robot is addressed. First, we analyze commercial pool cleaning robot mechanisms, and the merits and demerits of wireless version of a pool cleaning robot is introduced. And then the water-jet moving mechanism for a pool cleaning robot is proposed to improve energy efficiency and mechanical design advantage, which is one of the strong candidates for wireless pool cleaning robots. Next, the method of cleaning performance evaluation of pool cleaning robots is firstly defined with five key factors, and it was verified by experimental results. If the cleaning performance can be quantitatively defined, we can design optimally a pool cleaning robot, which results in the cost down.

A Study on Weld Pool Oscillation for Pool Geometry Measurement (완전용입 풀의 진동을 이용한 형상측정에 관한 연구)

  • 유중돈
    • Journal of Welding and Joining
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    • v.11 no.2
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    • pp.62-73
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    • 1993
  • Weld pool oscillation for the full-penetration GTA welding process was investigated for its possible application to weld penetration control through theoretical modeling and experiment. Energy method was used to estimate the natural frequency of the molten pool having the physically-acceptable weld geometry and oscillation modes. An unique experimental system was built which had the data acquisiton and video capabilities so that the pool oscillation signals and molten pool surfaces could be monitored continuously. Pool oscillation was detected through arc voltage and arc light emission simultaneously. The signal from arc light emission showed good coherence with that from arc voltage, and arc light generated the higher quality signal. The molten pool was found to oscillate in different oscillation modes based on the travel speed and weld geometry. The natural frequency estimated from the theoretical model agreed reasonably well with the experimental results.

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Assessment of Ventricular Function Using Gated Blood Pool Scan and Gated Blood Pool SPECT (게이트심장혈액풀 스캔과 게이트심장혈액풀 SPECT를 이용한 심실기능의 평가)

  • Park, Seok-Gun
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.2
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    • pp.100-106
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    • 2005
  • Non-invasive evaluation of cardiac function by nuclear medicine technologies are one of the major contribution of nuclear medicine. Gated cardiac blood pool scan was once a novel and robust technique which enabled evaluation of ventricular function. Concept of EKG gating was one of the major breakthrough in nuclear cardiology. According to the evolution of echocardiographic techniques, and as the evaluation of myocardial perfusion by perfusion SPECT became feasible, number of gated blood pool study dong in nuclear medicine laboratory is declining. And recently, evaluation of ventricular function with gated perfusion SPECT further decreased the use of gated blood pool scan. In this article, assessment of ventricular function using gated blood pool scan is discussed including some insight about the role of gated blood pool SPECT.

A Study of Fuzzy Control of Weld Pool Width in Gas Tungsten Arc Welding (Gas Tunsten Arc 용접에서 용융지폭의 퍼지 제어에 관한 연구)

  • Chung, Hyun-Kwon;Rhee, Se-Hun;Um, Ki-Woan
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.1
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    • pp.150-157
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    • 1997
  • Uniform weld pool shape is important in determining the weld quality. And weld pool width is one of the most dominant factors of the seld pool shape. In order to control the weld pool width, the fuzzy logic controller, which is well adapted to the complicated nonlinear systems such as welding, was used in this study. The weld pool image was obtained through CCD camera, and the weld pool width was calculated by processing the image. Uaing the calculated width, welding speed, as a control input, was inferred by the fuzzy logic controller. An uniform weld pool width can be successfully obtained regardless of the disturbances in the system.

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Investigation of decontamination characteristics of a serial multiple pool scrubber system for consequence mitigation of severe accidents

  • Hyeon Ho Byun;Man-Sung Yim
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4585-4600
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    • 2022
  • A pool scrubber is often used as a wet-type design to mitigate the consequence of a severe nuclear accident. While studies indicated higher decontamination performance of a deeper pool, utilizing a very tall pool can be problematic due to potential structural stability and water backflow issues. This study proposes, as an alternative to a single pool system, a pool scrubber system composed of serially connected multiple pools with lower heights. Since large fraction of aerosol removal takes place in the injection region, serially connected pool scrubber system is expected to enhance the overall decontamination capability of a pool scrubber system. To support the analysis of the proposed system's decontamination capability, a new computer model was developed in the study to describe the bubble size dependent effect on aerosol removal including the effect of pool residence time. The accuracy of the new model was examined against experimental data for its validation. The proposed scrubber system composed of serially connected multiple shorter pools is found to have much improved decontamination performance over the current single pool system design.