• Title/Summary/Keyword: Interference-free

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Some Philosophical Considerations for Autonomy of Nursing Care (간호의 독자성을 위한 철학적 고찰)

  • 최남희;이남희
    • Journal of Korean Academy of Nursing
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    • v.18 no.1
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    • pp.19-25
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    • 1988
  • To ensure the autonomy of nursing care aetivies is one of the major and most interesting issues in the field of nursing. The pertaining autonomy demands the nurse to make decisions of her or his own with out interference and free of help from other sides of health care agency. The whole process of autonomous nursing behavior should be judged and conveyed by the nurse only on the basis of the internal factors of her care to solve the problems of the client's disorder in health. Truth of nursing science and relevence of nursing conduct depend on our construction of internal basis and establishment of self-sufficient reference system. The information for efficient decision-making at the scene of nursing can only be supplied by a systematic body of nursing science consisting of true or properly corroborated propositions. The science of nursing can be autonomous when we have framework of explanation, independently of other sciences and the behavior of nursing care can factually be independent of and peculiar to that of other but similar fields only when the science of nursing is correspondently autonomous.

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MAC Protocol for Achieving Collision-free by Interference and End-to-end Delay Minimization in Wireless Sensor Networks (무선 센서 네트워크에서 패킷 간에 충돌을 줄이면서 전송지연을 감소시키는 MAC 프로토콜)

  • Jung, Woon-Pyo;Eom, Doo-Seop
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.709-710
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    • 2008
  • 무선 시스템에서는 수신도 송신처럼 에너지를 소모한다. 이러한 전력소모는 배터리를 전원으로 오랜시간 동작해야하는 센서 망에서는 치명적이다. 특히 센서 네트워크를 위해 제안된 경쟁기반 방식의 MAC은 에너지 소모를 야기하는 패킷간의 충돌을 최소화 하고 전송지연 을 줄이는 프로토콜이 필요하다. 본 논문에서는 adaptive S-MAC의 방식을 그대로 사용하면서 간섭에 의한 충돌을 줄이는 알고리즘을 이용하여 한 SYNC interval 내에서 최대 3홉까지 전송 가능한 MAC 프로토콜을 제안하였다. NS2의 시뮬레이션을 통해 제안한 MAC 프로토콜의 성능을 기존 MAC과 비교하여 증명하였다.

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A Study on Aerodynamic Characteristics with the Supersonic Nozzle Quantity (초음속노즐 수량 변화에 따른 공기역학적 특성의 연구)

  • Lee, Jong-Hoon;Kim, Kyoung-Ryun;Park, Jong-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.18 no.5
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    • pp.54-58
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    • 2015
  • The objective of this paper is to investigate the flow characteristics of the multi nozzle. The configurations of the single, the 3- and the 6-nozzle were selected under Mach number of 2.5. Under-expanded pressure ratio such as 1.2, 1.6 and 2.0 were selected to elucidate interference of the free jet. The flow visualization was carried out with the Schlieren system and a supersonic cold-flow system. Also, the flow characteristics were studied computationally with the density measurements. Reasonable agreement between experimental and theoric equation has been achieved qualitatively.

Manganese and Iron Interaction: a Mechanism of Manganese-Induced Parkinsonism

  • Zheng, Wei
    • Environmental Mutagens and Carcinogens
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    • v.23 no.4
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    • pp.115-130
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    • 2003
  • Idiopathic Parkinson's disease (IPD) represents a common neurodegenerative disorder. While epidemiological studies have suggested a number of risk factors including age, gender, race, and inherited disorder, the cumulative evidence supports the view that environmental or occupational exposure to certain chemicals may contribute to the initiation and progress of Parkinsonism. More recently, clinical and laboratory investigations have led to the theory that dysregulation of iron, an essential metal to body function, may underlie IPD by initiating free radical reaction, diminishing the mitochondrial energy production, and provoking the oxidative cytotoxicity. The participation of iron in neuronal cell death is especially intriguing in that iron acquisition and regulation in brain are highly conservative and thus vulnerable to interference from other metals that bear the similar chemical reactivity. Manganese neurotoxicity, induced possibly by altering iron homeostasis, is such an example. In fact, the current interest in manganese neurotoxicology stems from two primary concerns: its clinical symptoms that resemble Parkinson's disease and its increased use as an antiknock agent to replace lead in gasoline. This article will commence with addressing the current understanding of iron-associated neurodegenerative damage. The major focus will then be devoted to the mechanism whereby manganese alters iron homeostasis in brain.

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A study for the- reconstruction of free field sound source from the measured data in a closed wall by using Boundary Element Method (경계요소법을 이용한 음원의 자유음장 복원에 대한 연구)

  • Choi, Han-Lim;Lee, Duck-Joo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1747-1751
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    • 2000
  • It is well known that acoustic signals, even measured in an anechoic chamber, can be contaminated due to the wall interference. Therefore, it is necessary to reconstruct the original signal from the measured data, which is very critical for the case of measurement of source signal in a water tunnel. In this thesis, new methods for the reconstruction of sound sources are proposed and validated by using Boundary Element Method from measured data in a closed space. The inverse Helmholtz integral equation and its normal derivative are used for the reconstruction of sound sources in a closed space. An arbitrary Kirchhoff surface over the sources is proposed to solve the surface information instead of direct solution for the source. Although sound sources are not directly known by the inverse Helmholtz equation, the original sound source of pressure-field outside of the wall can be indirectly obtained by using this new method.

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A Study on the New Delay Stopping Criterion of Turbo Code in W-CDMA System (W-CDMA 시스템에서 터보 부호의 새로운 복호지연 감소방식에 관한 연구)

  • Park, No-Jin;Shin, Myung-Sik
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.8 no.4
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    • pp.207-215
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    • 2009
  • In recent digital communication systems, the performance of Turbo Code used as the error correction coding method depends on the interleaver size influencing the free distance determination and iterative decoding algorithms of the turbo decoder. However, some iterations are needed to get a better performance, but these processes require large time delay. Recently, methods of reducing the number of iteration have been studied without degrading original performance. In this paper, the new method combining ME (Mean Estimate) stopping criterion with SDR (sign difference ratio) stopping criterion of previous stopping criteria is proposed, and the fact of compensating each method's missed detection is verified Faster decoding realizes that reducing the number of iterative decoding about 1~2 times by adopting our proposed method into serially concatenation of both decoder. System Environments were assumed DS-CDMA forward link system with intense MAI (multiple access interference).

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An Echo Canceller Robust to Noise and Residual Echo

  • Kim, Hyun-Tae;Park, Jang-Sik
    • Journal of information and communication convergence engineering
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    • v.8 no.6
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    • pp.640-644
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    • 2010
  • When we talk with hands-free in a car or noisy lobby, the performance of the echo canceller degrade because background noise added to echo caused by the distance from mouth to microphone is relatively long. It gives a reason for necessity of noise-robust and high convergence speed adaptive algorithm. And if acoustic echo canceller operated not perfectly, residual signal going through the echo canceller to far-end speaker remains residual echo, which degrade quality of talk. To solve this problem, post-processing needed to remove residual echo ones more. In this paper, we propose a new acoustic echo canceller, which has noise robust and high convergence speed, linked with linear predictor as a post-processor. By computer simulation, it is confirmed that the proposed algorithm shows better performance from acoustic interference cancellation (AIC) viewpoint.

A Study on the Design of an Expert System for Diagnosing GIS Arrester (GIS용 피뢰설비의 전문가 시스템 설계에 관한 연구)

  • Han, Ju-Seop;Kim, Il-Kwon;Kil, Gyung-Suk;Rhyu, Keel-Soo;Kim, Tai-Jin;Kim, Jung-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.319-320
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    • 2005
  • This paper describes the principles and structures of an expert system for arrester diagnosis. The expert system analyzes and decides the arrester condition by total leakage current, its harmonic component, and temperature because the deterioration of arresters appeared in an increase of leakage current and surface temperature of it. Additionally, influence of system voltage harmonics and ambient temperatures on leakage current changes were considered in the design. The expert system is consisted of a data acquisition module and a computer for monitoring. The acquired analog data are digitalized and transmitted to the computer by an optical link which is free from interference.

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A Non-Canonical Linearly Constrained Constant Modulus Algorithm for a Blind Multiuser Detector

  • Jiang, Hong-Rui;Kwak, Kyung-Sup
    • ETRI Journal
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    • v.24 no.3
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    • pp.239-246
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    • 2002
  • We investigate an alternative blind adaptive multiuser detection scheme based on a non-canonical linearly constrained constant modulus (LCCM) criterion and prove that, under the constrained condition, the non-canonical linearly constrained constant modulus algorithm (LCCMA) can completely remove multiple -access interference. We further demonstrate that the non-canonical LCCM criterion function is strictly convex in the noise-free state, and that under the constrained condition, it is also strictly convex even where small noise is present. We present a simple method for selecting the constant as well as a stochastic gradient algorithm for implementing our scheme. Numerical simulation results verify the scheme's efficiency.

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A Linear Prediction Based Estimation of Signal-to-Noise Ratio in AWGN Channel

  • Kamel, Nidal S.;Jeoti, Varun
    • ETRI Journal
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    • v.29 no.5
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    • pp.607-613
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    • 2007
  • Most signal-to-noise ratio (SNR) estimation techniques in digital communication channels derive the SNR estimates solely from samples of the received signal after the matched filter. They are based on symbol SNR and assume perfect synchronization and intersymbol interference (ISI)-free symbols. In severe channel distortion where ISI is significant, the performance of these estimators badly deteriorates. We propose an SNR estimator which can operate on data samples collected at the front-end of a receiver or at the input to the decision device. This will relax the restrictions over channel distortions and help extend the application of SNR estimators beyond system monitoring. The proposed estimator uses the characteristics of the second order moments of the additive white Gaussian noise digital communication channel and a linear predictor based on the modified-covariance algorithm in estimating the SNR value. The performance of the proposed technique is investigated and compared with other in-service SNR estimators in digital communication channels. The simulated performance is also compared to the Cram$\acute{e}$r-Rao bound as derived at the input of the decision circuit.

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