• Title/Summary/Keyword: Transfer Delay

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Channel Transfer Function estimation based on Delay and Doppler Profiler for 5G System Receiver targeting 500km/h linear motor car

  • Suguru Kuniyoshi;Shiho Oshiro;Gennan Hayashi;Tomohisa Wada
    • International Journal of Computer Science & Network Security
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    • v.23 no.5
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    • pp.121-127
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    • 2023
  • A 500 km/h linear motor high speed terrestrial transportation service is planned to launch 2027 in Japan. In order to support 5G service in the train, the Sub-carrier spacing frequency of 30 kHz is planned to be used instead of common 15 kHz sub-carrier spacing to mitigate Doppler effect in such high-speed transportation. In addition, to increase the cell size of 5G mobile system, plural Base Station antenna will transmit the identical Down Link (DL) signal to form the expanded cell size along the train rail. In this situation, forward and backward antenna signals will be Doppler shifted by reverse direction respectively and the receiver in the train might suffer to estimate accurate Channel Transfer Function (CTF) for its demodulation. In this paper, Delay and Doppler Profiler (DDP) based Channel Estimator is proposed and it is successfully implemented in signal processing simulation system. Then the simulated performances are compared with the conventional Time domain linear interpolated estimator. According to the simulation results, QPSK modulation can be used even under severe channel condition such as 500 km/h, 2 path reverse Doppler Shift condition, although QPSK modulation can be used less than 200 km/h with conventional Channel estimator.

Interhospital Transfer of Emergency Patients and Informed Consent (응급환자의 전원과 의사의 설명의무)

  • Bae, Hyun-A
    • The Korean Society of Law and Medicine
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    • v.13 no.1
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    • pp.249-293
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    • 2012
  • Inter-hospital transfer, depending on its medical and legal appropriateness, affect the prognosis of patients and can even lead to legal disputes. As Emergency Medical Service Act, any physician shall, in case where deemed that pertinent medical service is unavailable for such patient with the capacities of the relevant medical institution, transfer without delay such patient to another medical institution where a pertinent medical service is available. For medico-legally appropriate inter-hospital transfer, the head of a medical institution shall, in case where he transfers an emergency patient provide medical instruments and manpower required for a safe transfer of the emergency patient, and furnish the medical records necessary for a medical examination at the medical institution in receipt of such patient. And transfer process must comply with the requirements prescribed by executive rule such as attachment of the referral, provision of ambulance, fellow riders and informed consent of transfer. Those engaged in emergency medical service shall explain an emergency medical service to an emergency patient and secure his consent. In addition to the duty to inform about emergency medical service to the patient and his or her legally representative, there is also a duty for doctors to sufficiently explain to the patient and his or her legally representative during inter-hospital transfer that the need for the transfer, the medical conditions of the patient to be transferred and emergency treatment that will be provided by the hospital from which the patient is going to transferred. Likewise, the hospital to which the patient is transferred must be thoroughly informed about matters such as the patient's conditions, the treatment the patient was given and reasons for transfer by transferring doctors.

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Transient Heat Transfer from a Suddenly Heated Verical Thin Wire (수직열선 근처의 과도 열전달 에 관한 실험적 연구)

  • 최만수;유정열;노승탁
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.7 no.4
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    • pp.461-468
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    • 1983
  • The series of experiments have been performed to study the transient heat transfer in air from a suddenly heated vertical thin wire. A platinum wire has been used as a resistance thermometer as well as a heating element to eliminate the disturbances in the measurements. The measured temperature as a function of time is compared with the calculated transient temperature with the aid of a pure conduction equation. The overshoot phenomena in terms of the Nusselt numbers have been detected and it is reasonable to define the delay time at which the onset of convection heat transfer occurs. The measured data are compared with the existing steady-state data and the agreements are reasonable within the comparable ranges.

Cracking Hen's Egg for Transgenesis, without Cracking Them (정자에 의한 외래 DNA의 계란내 도입: 유전자 변환 닭 생산을 위한 장애 극복)

  • 이기석;김기동;이상호
    • Korean Journal of Poultry Science
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    • v.26 no.2
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    • pp.109-118
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    • 1999
  • Hen's eggs have been regarded as one of the best animal bioreactors to produce biologically active peptides originated from many organisms including human. Despite the last decade's efforts to produce transgenic chicken for any commercial purposes, the results so far reported are very disappointing, indicating that hen's eggs are very difficult to crack for transgenesis. Comparatively large female gamete with enormous amount of yolk may be one of the major obstacles in achieving a similar feat to those of other vertebrate species including mouse, sheep, fish and frog. The delay or less efficiency evidenced may instruct to try an alternative way of gens transfer into chicken egg. Sperm-mediated gene transfer is one of them, and may require a great deal of understanding of mechanisms involved in early fertilization and embryonic development. In other animals where the technique was successful, basic mechanisms have been well studied and established only by painstaking efforts for decades. This paper discusses the accumulated knowledge on early fertilization mechanism in the chicken and how can this information be utilitzed to find the alternative gene transfer in making transgenic chicken.

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A Model Reduction and PID Controller Design Via Frequency Transfer Function Synthesis (주파수 전달함수 합성법에 의한 모델축소 및 PID 제어기 설계)

  • Kim, Ju-Sik;Kwang, Myung-Shin;Kim, Jong-Gun;Jeon, Byeong-Seok;Jeong, Su-Hyun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.1
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    • pp.34-40
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    • 2005
  • This paper presents a frequency transfer function synthesis for simplifying a high-order model with time delay to a low-order model. A model reduction is based on minimizing the error function weighted by the numerator polynomial of reduced systems. The proposed method provides better low frequency fit and a computer aided algorithm. And in this paper, we present a design method of PID controller for achieving the desired specifications via the reduced model. The proposed method identifies the parameter vector of PID controller from a linear system that develops from rearranging the two dimensional input matrices and output vectors obtained from the frequency bounds.

Performance Evaluation in Fin-Tube Heat Exchanger by Tow-In Winglet Pairs (Tow in 와류발생기에 의한 핀-관 열교환기의 성능실험)

  • ;Kahoru Torii
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.2
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    • pp.87-94
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    • 2003
  • To reduce the air side pressure drop in air-cooled heat exchanger, tow-in type winglet vortex generators are applied. A specially designed multiple-channel test core was used in the experiments for the various geometry of winglet vortex generators. The proposed tow-in type vortex generator gives significant separation delay, reduces form drag, and removes the zone of poor heat transfer from near-wake of the tubes. The results show the significant pressure drop reduction for the tow-in win91e1 vortex generators with the similar enhancement of the heat transfer as other vortex generator applications in heat exchanger. In the range of Reynolds number of 350 to 2100 the pressure drop decrease 8∼15% and 34∼55% for the in-line and staggered tube banks, respectively, compared to those without vortex generators.

The Causal Relationship between Dam Water Level and Fog Time - A Transfer Function Analysis - (변형 함수분석을 이용한 댐수위와 안개지속시간의 인과관계)

  • JaeGal, Don
    • Journal of the Korean Data and Information Science Society
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    • v.6 no.2
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    • pp.51-62
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    • 1995
  • As a result of the transfer function analysis on the casual relationship between Andong Dam water level and fog time in Andong City from March of 1981 to December of 1992, it should be referring to monthly increases in the water level having an effect on 0.89 hour per m increases in the fog time with 4 months delay. It is evident, hence, the artificial lake of the dam is one of the direct causes of fog. Based upon this objective evidence, water resources development policy and dam managment policy must be formulated.

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Transaction Effect Analysis through Compressing Realtime Transfer system (실시간 전송시스템의 무손실 압축을 통한 전송효과 연구)

  • 박인순;남상엽;박인정
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.79-85
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    • 2000
  • In the communication technology, there is necessary data compression to transfer data more quickly and bigger amount in the same condition. And that should bring down the cost consequently. This paper shows that how to apply compression software and hardware to attain the issue that mentioned previous in data communication technology as well as, trying to find the solution for the system delay problem and to improve efficiency demanded to them. To achieve these purposes, 1 will study and analyze the efficiency of compression system to realize realtime data compression transfer system using LZS compression algorithm.

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Adaptive Active Noise Control of Single Sensor Method (단일 센서 방식의 적응 능동 소음제어)

  • 김영달;장석구
    • Journal of KSNVE
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    • v.10 no.6
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    • pp.941-948
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    • 2000
  • Active noise control is an approach to reduce the noise by utilizing a secondary noise source that destructively interferes with the unwanted noise. In general, active noise control systems rely on multiple sensors to measure the unwanted noise field and the effect of the cancellation. This paper develops an approach that utilizes a single sensor. The noise field is modeled as a stochastic process, and an adaptive algorithm is used to adaptively estimate the parameters of the process. Based on these parameter estimates, a canceling signal is generated. Oppenheim assumed that transfer function characteristics from the canceling source to the error sensor is only a propagation delay. This paper proposes a modified Oppenheim algorithm by considering transfer characteristics of speaker-path-sensor This transfer characteristics is adaptively cancelled by the proposed adaptive modeling technique. Feasibility of the proposed method is proved by computer simulations with artificially generated random noises and sine wave noise. The details of the proposed architecture. and theoretical simulation of the noise cancellation system for three dimension enclosure are presented in the Paper.

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Mathematical Model for Mean Transfer Delay of Web Object in Initial Slow Start Phase (초기 슬로우 스타트 구간에서 웹 객체의 평균 전송 시간 추정을 위한 수학적 모델)

  • Lee, Yong-Jin
    • 대한공업교육학회지
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    • v.33 no.2
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    • pp.248-258
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    • 2008
  • Current Internet uses HTTP (Hyper Text Transfer Protocol) as an application layer protocol and TCP (Transmission Control Protocol) as a transport layer protocol to provide web service. SCTP (Stream Control Transmission Protocol) is a recently proposed transport protocol with very similar congestion control mechanisms as TCP, except the initial congestion window during the slow start phase. In this paper, we present a mathematical model of object transfer latency during the slow start phase for HTTP over SCTP and compare with the latency of HTTP over TCP. Validation of the model using experimental result shows that the mean object transfer latency for HTTP over SCTP during the slow start phase is less than that for HTTP over TCP by 11%.