• Title/Summary/Keyword: Expansion Devices

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A Study of Longitudinal Forces and Displacements in a Multi-Span Bridge Equipped with a CWR Track (장대레일이 설치된 교량에서의 축방향 변위 및 축력 변화 연구)

  • Lee, Joo-Heon;Huh, Young
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.442-449
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    • 1999
  • Due to temperature variations, considerable longitudinal rail forces and displacements may develop in continuous welded rail(CWR) track on long-span bridges or viaducts. Excessive relative displacements between sleepers and ballast bed may disturb the stable position of the track in the ballast which results in a lower frictional resistance. Generally, these problems are solved by installing rail expansion devices. However the application of expansion devices in high-speed tracks on existing bridges, as a means to prevent excessive longitudinal displacements and forces, is not attractive method due to comfort, safety and maintenance aspects. An alternative and very effective solution is possibly the use of so-called zero longitudinal restraint(ZLR) fastenings over some length of the track. The calculations, carried out in this respect, show a considerable reduction of track displacements, track forces, and the relative sleeper/ballast displacements. This reduction depends on the length over which these fastenings are installed. In this paper calculations of the longitudinal displacments and forces in a CWR track and substructure resulting from thermal, mechanical and kinematical loads were carried out using the FEM analysis program LUSAS

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The UPnP Expansion for Internet Home Network Electrical Appliance Control of Ubiquitous environment (인터넷 홈 네트워크 가전 제어를 위한 UPnP 확장)

  • Cho, Kyung-Hee;Lee, Sung-Joo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.695-698
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    • 2007
  • The control of electrical appliances residing in the home network can be accomplished via Internet with the UPnP expansion without modifying an existing UPnP. In this paper, we propose the Internet Gateway that consists of an UPnP IGD(Internet Gateway Device) DCP(Device Control Protocol) and an UPnP Bridge as a system to control electrical appliances of home network. UPnP IGD DCP is to enable the configurable initiation and sharing of Internet connections as well as assuring advanced connection-management features and management of host configuration service. It also supports transparent Internet access by non-UPnP-certified devices. UPnP Bridge searches for local home network devices by sending control messages, while control point of UPnP Bridge looks up devices of interest on the Internet, subsequently furnishing the inter-networking controlling among devices which belong to different home network systems. With our approach, devices on one home network can control home electrical appliances on the other hone network via Internet through IGD DCP with control commands of UPnP.

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High power efficient solar cell using the organic polymer materials (유기고분자 재료를 이용한 우수한 효율의 태양전지)

  • Lee, Junghoon;Park, Jukwang;Chang Seoul
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.356-357
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    • 2003
  • Organic materials are suitable for use in photoelectric conversion devices. Thus, Organic semiconductors are promising materials for photovoltaic devices and other optoelectronic applications such as light emitting diodes(LED). The organic solar cell seems to be the usefulness in comparison with the inorganic solar cell in terms of workability, ease of processing, low cost, flexibility and area expansion. (omitted)

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Development of Open H/W-Based IEEE 11073 Agent and Manager for Non-Standard Health Devices (비표준 건강 기기를 위한 오픈 H/W 기반의 IEEE 11073 에이전트 및 매니저 개발)

  • Lee, Jang-Yeol;Jeong, Yeong-Rok;Park, Hee-Dong
    • Journal of Korea Multimedia Society
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    • v.19 no.3
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    • pp.595-602
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    • 2016
  • With the evolution and development of many kinds of healthcare devices and techniques, u-health standards have emerged as a major issue. Yet, most legacy medical devices and systems are still being used without deployment of the standards. Therefore, it is required to support backward compatibility for u-health standard-compliant systems to communicate with legacy non-standard medical and healthcare devices. This paper proposes a new scheme to support backward compatibility of IEEE 11073 system by adding a codec module to IEEE 11073 agent. The codec converts data sent by non-standard health devices to IEEE 11073 MDER data. Plus, we implemented the proposed IEEE 11073 agent with an Intel Edison board which is one of popular open source H/W platforms. The IEEE 11073 manager of the proposed system can monitor and control legacy non-standard devices through the proposed agent system. In our experimental results, we examined the proposed system can support interoperability between u-health standard and non-standard devices and contribute to the growth and expansion of u-health services.

Blossom smart expander technology for tissue expander-based breast reconstruction facilitates shorter duration to full expansion: A pilot study

  • Choi, Youna K.;Rochlin, Danielle H.;Nguyen, Dung H.
    • Archives of Plastic Surgery
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    • v.47 no.5
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    • pp.419-427
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    • 2020
  • Background This study evaluated the Blossom system, an innovative self-filling, rate-controlled, pressure-responsive saline tissue expander (TE) system. We investigated the feasibility of utilizing this technology to facilitate implant-based and combined flap with implant-based breast reconstruction in comparison to conventional tissue expansion. Methods In this prospective, single-center, single-surgeon pilot study, participants underwent either implant-based breast reconstruction or a combination of autologous flap and implantbased breast reconstruction. Outcome measures included time to full expansion, complications, total expansion volume, and pain scores. Results Fourteen patients (TEs; n=22), were included in this study. The mean time to full expansion was 13.4 days (standard error of the mean [SEM], 1.3 days) in the combination group and 11.7 days (SEM, 1.4 days) in the implant group (P=0.78). The overall major complication rate was 4.5% (n=1). No statistically significant differences were found in the complication rate between the combination group and the implant group. The maximum patient-reported pain scores during the expansion process were low, but were significantly higher in the combination group (mean, 2.00±0.09) than in the implant group (mean, 0.29±0.25; P=0.005). Conclusions The reported average duration for conventional subcutaneous TE expansion is 79.4 days, but this pilot study using the Blossom system achieved an average expansion duration of less than 14 days in both groups. The Blossom system may accommodate single-stage breast reconstruction. The overall complication rate of this study was 4.5%, which is promising compared to the reported complication rates of two-stage breast reconstruction with TEs (20%-45%).

Marker-less Calibration of Multiple Kinect Devices for 3D Environment Reconstruction (3차원 환경 복원을 위한 다중 키넥트의 마커리스 캘리브레이션)

  • Lee, Suwon
    • Journal of Korea Multimedia Society
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    • v.22 no.10
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    • pp.1142-1148
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    • 2019
  • Reconstruction of the three-dimensional (3D) environment is a key aspect of augmented reality and augmented virtuality, which utilize and incorporate a user's surroundings. Such reconstruction can be easily realized by employing a Kinect device. However, multiple Kinect devices are required for enhancing the reconstruction density and for spatial expansion. While employing multiple Kinect devices, they must be calibrated with respect to each other in advance, and a marker is often used for this purpose. However, a marker needs to be placed at each calibration, and the result of marker detection significantly affects the calibration accuracy. Therefore, a user-friendly, efficient, accurate, and marker-less method for calibrating multiple Kinect devices is proposed in this study. The proposed method includes a joint tracking algorithm for approximate calibration, and the obtained result is further refined by applying the iterative closest point algorithm. Experimental results indicate that the proposed method is a convenient alternative to conventional marker-based methods for calibrating multiple Kinect devices. Hence, the proposed method can be incorporated in various applications of augmented reality and augmented virtuality that require 3D environment reconstruction by employing multiple Kinect devices.

A Study on the Effect of the Digital Nomadism on Modern Fashion

  • Kim Mi-Hyun;Chung Heung-Sook Grace
    • International Journal of Costume and Fashion
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    • v.4 no.2
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    • pp.45-55
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    • 2004
  • Rapid informatization and technology advance in the 21st century has invited a new paradigm and changed many things in human life pattern. The impact of mobility seen in this digital nomadism has brought about, when it comes to clothing, a change in its unique meaning, that is, the graftage of high technology onto present nomad's life style who live moving around all the time due to the expansion of mobile environment. As the fruits of this expansion of mobile environment and technology advance in wireless telecommunication, easy-to-carry smaller sized devices such as cell phones, PDA, and MP3 players represent the present times, while the future would be an 'era of wearing' in which kinds of electronic devices and systems are integrated into clothing. Thus in this study, concept of wearable computer seen in the 21st century's digital nomadism was reviewed, and figurativeness and anesthetic value of wearable computer were discussed in association with the change in high style image resulted from technology advance and change of life style. By drawing a justice from which, value of future fashion was also prospected.

A Study on Dynamic Characteristics of a Refrigeration System by Controlling the Evaporator Superheat (증발기 과열도제어에 따른 냉동장치의 동특성에 관한 연구)

  • 김재돌;오후규;윤정인
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.8
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    • pp.2012-2021
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    • 1995
  • An experimental study was performed for the analysis of dynamic characteristics of refrigeration system by controlling the evaporator superheat. Experimental data have been taken utilizing two different devices, thermostatic expansion valve(T.E.V.) and electronic expansion valve(E.E.V.), for the control of the evaporator superheat. The ranges of parameters, such as superheat, mass flow rate of refrigerant and inlet temperature of evaporator were 5-30.deg. C 90-170 kg/h and 10-25.deg. C, respectively. The data taken from the T.E.v.and E.E.v.were discussed with the control of the superheat, pressure drop, refrigerating capacity, compression work, evaporating temperature, condensing temperature and COP affecting performance characteristics of refrigeration system. In case of the refrigerant flow control with T.E..V., the superheat and pressure drop of the evaporator varied periodically, but the control with E.E.V., the parameters were very stable. In E.E.v.control, refrigerating capacity, compression work and evaporating temperature were decreased with increasing superheat, and the highest COP was obtained in the range of superheat from 5.deg. C to 15.deg. C.

A Monitoring System for Solar Street Lights Using Mobile Devices (모바일 장치를 이용한 태양광 가로등 모니터링 시스템)

  • Yang, Minhyeok;Oh, Byoung-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.3
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    • pp.15-21
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    • 2014
  • The utilization range of mobile devices is becoming broader than before due to the rapid development of the mobile market. Furthermore, the demands for computer-aided management are increasing due to the extensive expansion of the installation of solar street lights. In this paper, we propose a system which can be used to observe solar street lights. The manager of the system can control and manage the solar street lights using video images on a mobile device.

Examples of Trolley Wire Resistance Influential on The Movement of Tensioning Devices (장력조정장치의 동작에 영향을 미치는 가선저항의 사례)

  • Yoon, Yong-Han;Yim, Geum-Kwang;Han, Yang-Gyu
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.886-892
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    • 2007
  • This paper presents examples of trolley wire resistance influential on the movement of tensioning devices. Therefore, this study is on the examples of trolley wire resistance which keep tensioning devices from working properly to the expansion and contraction in accordance with temperature change of overhead trolley wire system such as messenger wire and contact wire. Trolley wire resistance interrupts the working of tensioning device and drops the capacity of trolley wire. Reduced trolley wire capacity lowers the performance of current collection and has a bad effect on electrical train operation. So it is desirable to reduce the factors increasing trolley wire resistance to the minimum from the designing and construction stage of overhead trolley wire system. This study will introduce this problem and suggest the solution.

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