• Title/Summary/Keyword: link-status

Search Result 278, Processing Time 0.034 seconds

Magnet applications of HTS wires

  • Oh, Sang-Soo
    • 한국초전도학회:학술대회논문집
    • /
    • v.10
    • /
    • pp.27-34
    • /
    • 2000
  • HTS wires processed by PIT method are now available for magnet applications. But, those wires can not be used over 40 K due to weak link. This leads to necessity of development of coated conductor which can retain high $J_c$ at high field in liquid nitrogen. In this paper, various technical issues and the R&D status for both PIT wires and coated conductor were discussed. The difference of coated conductor's processes were also investigated and summarized. Various requirements for a design of HTS magnets were discussed. Anisostropic $J_c$ property with respect to magnetic field was considered to determine the coil's critical current. Low n value is a critical parameter to degrade a field stability with respect to time for a persistent mode HTS magnet. The relation between the margin of operation current and n value was investigated. Prototype HTS magnets with PIT wires are being developed for various applications such as crystal growth, MRI, magnetic separator and etc. HTS magnets will come into wide use in various fields of industries if the HTS wires with a low performance cost is developed.

  • PDF

Design of Digital Controllers with Self-Validating Intelligent Sensors (Self-Validating 지능형 센서를 사용한 디지털 제어기의 설계)

  • 나승유;배희종
    • Proceedings of the IEEK Conference
    • /
    • 2000.06e
    • /
    • pp.51-54
    • /
    • 2000
  • We are concerned with processing methods of the measurement values of sensors in the control system. When some faults happen to sensor components, the measurement value of sensors cause the malfunction of the plant. So it is necessary to detect and reduce the influence of faults to control with reliability for the overall system. The sensor status must be always good for best demonstration of the controller performance. A self-validating sensor detects the sensor state from the measurement value, reconstruct a soft sensor and can improve reliability of the sensor. If sensor faults, the sensor is detected and reconstructed with the best estimate from its correlation to other sensors and historical data. It is applied to the control of a flexible link system with the sensor fault problems in the light sensor module for position to show the applicability. In this paper, we propose a digital controller which reduces deflection of the moving set-point by reconstructing output of a sensor when the sensor fault is detected.

  • PDF

Sub-channel Assignments by Link Status on OFDMA Systems for WiBro Service (휴대 인터넷을 위한 OFDMA 시스템에서 무선채널 상태에 따른 서브채널할당)

  • Lim Seog-Ku
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2005.11a
    • /
    • pp.596-600
    • /
    • 2005
  • In High-speed Portable Internet system to improve performance of whole system, adaptive modulation and coding technology is used, this technology changes modulation and encoding techniques depending on wireless channel environment. Modulation technology that is used in High-speed Portable Internet system is BPSK, QPSK, 16QAMs and 64QAMs. If terminal is distant from base station transceiver system, BPSK or QPSK technology Is used and 16QAMs or 64QAM technology is used if is near in the base station transceiver system. In this paper, number of sub-channel in each modulation technology minimized total transmitting number of PDU is analyzed for efficient radio resources usage. For this, simulation is conducted and the results are presented at High-speed Portable Internet system environments.

  • PDF

Standalone Maritime Aids-To-Navigation AIS Mobile Station

  • Lee, Chee-Cheong;Park, Soo-Hong
    • Journal of information and communication convergence engineering
    • /
    • v.7 no.3
    • /
    • pp.297-303
    • /
    • 2009
  • Automatic Identification System (AIS) is a VHF radio broadcasting system where transmits packets of data via VHF data link. It enables vessels and coastal-based station that equipped with AIS equipment to send and receive useful information. This information can be help in situational awareness and provide a means to assist in collision avoidance. In addition, AIS can be use as Aid-To-Navigation, by providing the location and additional information on buoys and lights. Besides, it can also contain details information in meteorological status of a particular ship location. This paper presents the standalone AIS system that able to receive and report own ship location, meteorological data collection and broadcast safety related information if necessary. With the unique ship's MMSI number, all the information of that particular ship can be monitor by using AIS program written in C++ programming language.

Fair TCP Window-based Control in Single Congested Network with Explicit Congestion Notification (TCP 단일 혼잡 망에서의 ECN을 이용한 공정한 윈도우 제어)

  • Byun, Hee-Jung;Lim, Jong-Tae
    • Proceedings of the KIEE Conference
    • /
    • 2002.11c
    • /
    • pp.27-30
    • /
    • 2002
  • In this paper, we propose a window-based congestion control algorithm to achieve a fair sharing of the available bandwidth in ECN capable heterogeneous TCP networks with a single bottleneck link. The proposed algorithm is based on extracting the network status from the successive binary congestion information provided by ECN. From the explicit network information, we estimate the fair window size proportional to the propagation delay. Through simulations, the effect and performance of the proposed algorithm are shown for the heterogeneous networks.

  • PDF

TCP Friendly Rate Control for MPEG-4 Video Transmission in Wireless Networks (무선 네트워크에서 MPEG-4 비디오 전송을 위한 TCP Friendly 전송율 제어 기법)

  • Bai, Song-Nan;Lee, Do-Hyeon;Jung, Myong-Hwan;Jung, Jae-Il
    • Proceedings of the IEEK Conference
    • /
    • 2006.06a
    • /
    • pp.749-750
    • /
    • 2006
  • TFRC is an equation-based rate control scheme originally developed for video transmission over wired networks. When applied to the wireless networks, it suffers from performance degradation. In this thesis, we propose an end-to-end loss discrimination algorithm to improve the performance of TFRC over wireless networks. The proposed WLD-TFRC scheme combines Spike and WLD(Wireless Loss Discount) algorithms to discriminate wireless loss from congestion loss, and to discount feedback loss event rate. Experimental results show that WLD-TFRC outperforms the original TFRC and effectively reduce the degradation of the video quality caused by the wireless link status.

  • PDF

Adaptive Cross-Layer Packet Scheduling Method for Multimedia Services in Wireless Personal Area Networks

  • Kim Sung-Won;Kim Byung-Seo
    • Journal of Communications and Networks
    • /
    • v.8 no.3
    • /
    • pp.297-305
    • /
    • 2006
  • High-rate wireless personal area network (HR-WPAN) has been standardized by the IEEE 802.15.3 task group (TG). To support multimedia services, the IEEE 802.15.3 TG adopts a time-slotted medium access control (MAC) protocol controlled by a central device. In the time division multiple access (TDMA)-based wireless packet networks, the packet scheduling algorithm plays a key role in quality of service (QoS) provisioning for multimedia services. In this paper, we propose an adaptive cross-layer packet scheduling method for the TDMA-based HR-WPAN. Physical channel conditions, MAC protocol, link layer status, random traffic arrival, and QoS requirement are taken into consideration by the proposed packet scheduling method. Performance evaluations are carried out through extensive simulations and significant performance enhancements are observed. Furthermore, the performance of the proposed scheme remains stable regardless of the variable system parameters such as the number of devices (DEVs) and delay bound.

Oncogenic RUNX3: A Link between p53 Deficiency and MYC Dysregulation

  • Date, Yuki;Ito, Kosei
    • Molecules and Cells
    • /
    • v.43 no.2
    • /
    • pp.176-181
    • /
    • 2020
  • The RUNX transcription factors serve as master regulators of development and are frequently dysregulated in human cancers. Among the three family members, RUNX3 is the least studied, and has long been considered to be a tumor-suppressor gene in human cancers. This idea is mainly based on the observation that RUNX3 is inactivated by genetic/epigenetic alterations or protein mislocalization during the initiation of tumorigenesis. Recently, this paradigm has been challenged, as several lines of evidence have shown that RUNX3 is upregulated over the course of tumor development. Resolving this paradox and understanding how a single gene can exhibit both oncogenic and tumor-suppressive properties is essential for successful drug targeting of RUNX. We propose a simple explanation for the duality of RUNX3: p53 status. In this model, p53 deficiency causes RUNX3 to become an oncogene, resulting in aberrant upregulation of MYC.

Three Phase Inverter System Utilizing Three Bi-directional Buck-Boost Converter (3개의 양방향 벅-부스트 컨버터를 이용한 3상 인버터 시스템)

  • Kim, Sung-Young;Nam, Kwang-Hee
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.06a
    • /
    • pp.551-554
    • /
    • 2006
  • An inverter system which consists of three bi-directional buck-boost converters, is proposed for motor driving. Three phase sinusoidal output voltages can be generated by utilizing three buck-boost converters. The advantage of this scheme is that it does not require a separate DC-DC converter for motor driving, i.e. inverter function is combined into the three DC-DC converters. This topology is suitable for inverters for hybrid or fuel cell vehicles where DC link voltage is subject to change depending upon charging status or output power. So the proposed system is capable of driving motor at high speed. The converter system is controlled by PI controller and simulation results done by MATLAB SIMULINK are provided.Ҙ?⨀ሉȀ̀㘰々K䍄乍?ጊ츀Ѐ㔹〻Ԁ䭃䑎䴀

  • PDF

Examining the Role of Psychosocial Stressors in Hypertension

  • Komal, Marwaha
    • Journal of Preventive Medicine and Public Health
    • /
    • v.55 no.6
    • /
    • pp.499-505
    • /
    • 2022
  • Despite advances in medicine and preventive strategies, fewer than 1 in 5 people with hypertension have the problem under control. This could partly be due to gaps in fully elucidating the etiology of hypertension. Genetics and conventional lifestyle risk factors, such as the lack of exercise, unhealthy diet, excess salt intake, and alcohol consumption, do not fully explain the pathogenesis of hypertension. Thus, it is necessary to revisit other suggested risk factors that have not been paid due attention. One such factor is psychosocial stress. This paper explores the evidence for the association of psychosocial stressors with hypertension and shows that robust evidence supports the role of a chronic stressful environment at work or in marriage, low socioeconomic status, lack of social support, depression, anxiety, post-traumatic stress, childhood psychological trauma, and racial discrimination in the development or progression of hypertension. Furthermore, the potential pathophysiological mechanisms that link psychosocial stress to hypertension are explained to address the ambiguity in this area and set the stage for further research.