• Title/Summary/Keyword: Self-noise

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Comparison of Sleep Patterns between Home and Institute Elderly People (재가노인과 시설노인의 수면양상에 대한 비교연구)

  • Kim, Kwuy-Bun;Sok, So-Hyune;Kim, In-Sook
    • Journal of East-West Nursing Research
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    • v.5 no.1
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    • pp.65-74
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    • 2000
  • This study was attempted to show basic data for search of nursing intervention about sleep improving in home and institute elderly peoples. Research design was cross-sectional survey method for comparison of sleep patterns and another variables between home and institute elderly peoples. Subjects were sampled by purpose as home and institute elderly peoples at age of 65 or older in Seoul or nearly. The survey questionnaire was used by modification of sleep questionnaire which Kim, O, Song & Bak(1997) developed. Data were collected between December, 1999 and April, 2000. And data were analyzed by SPSS PC+ for purpose of research. Results are as follows: 1. Home and institute elderly peoples, all were change of sleep patterns and sleep pattern was showed early sleeping down. But institute elderly peoples slept earlier than home elderly peoples. 2. As rest of morning, difficulty of falling asleep and disturbance of re-asleep, subjective thinking and feeling were showed more negative thing home elderly peoples than institute elderly peoples. As frequency of falling asleep within 5 min in 1 week, frequency of falling asleep over 30 min in 1 week and frequency of awakening in a day, objective frequency were showed more insomnia institute elderly peoples than home elderly peoples. Home elderly peoples didn't nap most and institute elderly peoples napped on very short time. 3. Regarding sleep-disturbing factors, physical factor was popularly joint-disturbance in all, home and institute elderly peoples. Environmental factor was popularly noise, particularly institute elderly peoples. Emotional factor wasn't all. 4. Practiced strategies for better sleep was popularly TV/Radio in home elderly peoples and were popularly regular sleep and religious action in institute elderly peoples. From the results of this study, home elderly peoples need nursing intervention of improving self-satisfaction on sleep and institute elderly peoples need nursing intervention of decreasing falling asleep-disturbing and decreasing frequency of awakening in sleep.

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A New Switchable Dual Mode Voltage Controlled Oscillator (새로운 구조의 스위치형 이중 모드 전압 제어 발진기)

  • Ryu, Jee-Youl;Deboma, Gilbert D.
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.869-872
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    • 2005
  • This paper presents a new switchable dual mode VCO(Voltage-Controlled Oscillator). The VCO is efficient in dual mode operation and has self-bias adjustment based on the operation frequencies of 2.4 GHz and 5 GHz. The switching is done using MOS transistors and tuning is done using MOS varactors. It is implemented using TSMC 0.18${\mu}$m CMOS technology. It is powered by 1.8V supply. The measured results showed that the overall tuning range is approximately 13% at 5 GHz and 8% at 2.4 GHz. The measured phase noise is approximately -102 dBc/Hz at 1 MHz offset for 5 GHz and -89 dBc/Hz at 600kHz offset for 2.4 GHz. The VCO showed tail currents of 2mA in 5GHz mode and 2.5mA in 2.4GHz mode from a 1.8 V supply, respectively.

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A Study on the Reversible SCR Servo Amplifier (정역전이 가능한 SCR 서보증폭기에 관한 연구)

  • Ahn, B. W.;Park, S. K.
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.2
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    • pp.190-198
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    • 1995
  • Many industrial servo amplifiers employ power transister as output device. Thyristor converters are not adopted to drive servo motor, although thyristor is superior to power TR in power rating, noise immunity, price, and size. The reason is, thyristor has no ability of self turn - off. Here in this paper line commutation, in which thyristor is turned off naturally since cathode voltage is higher than anode as time goes by, is employed to turn on thyristor with a delicate sequence. We developed thyristor servo amplifier which does not cause any damage on thyristor because it is designed to prevent triggering the two SCRs in the same arm simultaneously. And it was made clearly how to trigger SCR without any power line shorting and also harmonic analysis is carried out with the aid of FFT analyzer and proved that it can be used even severe reactive load. The designed circuit operated as a good DC amplifier in conventinal servomotor and the results can be use as a position control system application.

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High-Performance Millimeter Wave Harmonic Output Oscillator using Sub-Harmonic Wave Injection-Synchronization (서브하모닉 주입동기에 의한 밀리미터파 대역 고조파 발진기의 고성능화)

  • Choi, Young-Kyu;Nam, Byeong-Gun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.1
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    • pp.17-24
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    • 2008
  • This paper deals with a millimeter wave source which is utilizing sub-harmonic injection-synchronization technique. A 8.7GHz oscillator with MES-FET is fabricated, and is driven as a harmonic output oscillator at 17.4GHz by means of sub-harmonic injection-synchronization. The oscillator operates as a multiplier as well as oscillator in this system. Adopting this technique, we can obtain a high stable, high frequency millimeter wave source even though self-oscillating frequency of an oscillator is relatively low. In the experiments, the range of injection-synchronization is about 26MHz and is proportional to the input sub-harmonic power. From the spectrum analysis of the 2nd harmonic output. we blow that the phase noise of the harmonic oscillator is remarkably decreased.

Analysis of Scientific and Subjective Sleeping Measurements and Environmental Factors that Influence Sleep Efficiency of Seafarers (선원의 과학적 및 주관적 수면측정과 수면효율성에 영향을 주는 환경요인 분석)

  • Kwon, Young-Tae;Kim, Byeong-Jo
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.3
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    • pp.185-198
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    • 2022
  • Purpose : We conducted a study to propose comparing subjective sleeping states data that was collected through scientifically measuring by using smartwatch and surveys for seafarers. In addition, we conducted a study to provide sleep though analysis of the environmental factors that influence the sleep efficiency of seafarers. Methods : For scientific measurement of seafarers' sleeping states, we measured the sleep hours and sleep efficiency for at least 3 days by using the healthcare function of smartwatches which are wearable devices. As for subjective sleeping states, we collected data on sleep hours and satisfaction rates on the quality of sleep through a survey. Lastly, as for the environmental factors that affect the sleep efficiency which is measured by smartwatches such as physical environment, bedroom space, bedroom furniture, bedding, a survey by self-evaluation method was conducted. Results : There were significant differences in the scientific sleep hours measurement values for all seafarers and the average sleep hours in the subjective survey. There were significant differences in the scientific sleep efficiency measurements of all the seafarers and the sleep satisfaction of the subjective survey, and there was no correlation between the scientific sleep efficiency and the subjective sleep satisfaction of all the seafarers. Among the environmental factors affecting the sleep efficiency of the seafarers, humidity variable had the most influence, and vibration and illuminance variables were also shown to have a very significant effect. Conclusion : We propose the measuring method that can analyze the quantitative and qualitative sleep states of the seafarers by using small activity recorders. In addition, it is very important to control humidity, vibration, and illuminance among ship environmental factors, and comfort, noise and bedroom size should also be reflected.

Fundamental Metrology by Counting Single Flux and Single Charge Quanta with Superconducting Circuits

  • Niemeyer, J.
    • Progress in Superconductivity
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    • v.4 no.1
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    • pp.1-9
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    • 2002
  • Transferring single flux quanta across a Josephson junction at an exactly determined rate has made highly precise voltage measurements possible. Making use of self-shunted Nb-based SINIS junctions, programmable fast-switching DC voltage standards with output voltages of up to 10 V were produced. This development is now extended from fundamental DC measurements to the precise determination of AC voltages with arbitrary waveforms. Integrated RSFQ circuits will help to replace expensive semiconductor devices for frequency control and signal coding. Easy-to-handle AC and inexpensive quantum voltmeters of fundamental accuracy would be of interest to industry. In analogy to the development in the flux regime, metallic nanocircuits comprising small-area tunnel junctions and providing the coherent transport of single electrons might play an important role in quantum current metrology. By precise counting of single charges these circuits allow prototypes of quantum standards for electric current and capacitance to be realised. Replacing single electron devices by single Cooper pair circuits, the charge transfer rates and thus the quantum currents could be significantly increased. Recently, the principles of the gate-controlled transfer of individual Cooper pairs in superconducting A1 devices in different electromagnetic environments were demonstrated. The characteristics of these quantum coherent circuits can be improved by replacing the small aluminum tunnel Junctions by niobium junctions. Due to the higher value of the superconducting energy gap ($\Delta_{Nb}$$7\Delta_{Al}$), the characteristic energy and the frequency scales for Nb devices are substantially extended as compared to A1 devices. Although the fabrication of small Nb junctions presents a real challenge, the Nb-based metrological devices will be faster and more accurate in operation. Moreover, the Nb-based Cooper pair electrometer could be coupled to an Nb single Cooper pair qubit which can be beneficial for both, the stability of the qubit and its readout with a large signal-to-noise ratio..

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TCN-USAD for Anomaly Power Detection (이상 전력 탐지를 위한 TCN-USAD)

  • Hyeonseok Jin;Kyungbaek Kim
    • Smart Media Journal
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    • v.13 no.7
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    • pp.9-17
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    • 2024
  • Due to the increase in energy consumption, and eco-friendly policies, there is a need for efficient energy consumption in buildings. Anomaly power detection based on deep learning are being used. Because of the difficulty in collecting anomaly data, anomaly detection is performed using reconstruction error with a Recurrent Neural Network(RNN) based autoencoder. However, there are some limitations such as the long time required to fully learn temporal features and its sensitivity to noise in the train data. To overcome these limitations, this paper proposes the TCN-USAD, combined with Temporal Convolution Network(TCN) and UnSupervised Anomaly Detection for multivariate data(USAD). The proposed model using TCN-based autoencoder and the USAD structure, which uses two decoders and adversarial training, to quickly learn temporal features and enable robust anomaly detection. To validate the performance of TCN-USAD, comparative experiments were performed using two building energy datasets. The results showed that the TCN-based autoencoder can perform faster and better reconstruction than RNN-based autoencoder. Furthermore, TCN-USAD achieved 20% improved F1-Score over other anomaly detection models, demonstrating excellent anomaly detection performance.

When Evaluated Using CT Imaging Phantoms AAPM Phantom Studies on the Quantitative Analysis Method (AAPM Phantom을 이용한 CT 팬텀 영상 평가 시 정량적 분석 방법에 관한 연구)

  • Kim, Young-Su;Ye, Soo-Young;Kim, Dong-Hyun
    • The Journal of the Korea Contents Association
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    • v.16 no.8
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    • pp.592-600
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    • 2016
  • AAPM CT performance for special medical equipment quality control checks using a standard phantom for evaluation, using the evaluator's subjective assessment as to minimize errors due computerized assessment program to evaluate their usefulness. Phantom for evaluation AAPM CT Performance Phantom: was used, the default shooting conditions are the same as quality control checks. And, we use IMAGE J to evaluate the program. Quantitative evaluation with CT attenuation coefficient and the noise measurement, the uniformity measurement, the slice thickness measurement, contrast resolution of the measurement, a phantom image of the spatial resolution determined by the evaluation program is evaluated as self-extracting the result after processing the image, CT uniformity measurement for the evaluation that was smaller and the standard deviation of a video image processing more uniform slice thickness measurements it is difficult to evaluate due to the difference of the ratio of the measured value of the phantom image. Contrast resolution was measured cylindrical diameter 6th evaluate the shape of a circle obtained a mean value and a standard deviation of diameters, the spatial resolution of the group of source, including acceptance criteria automatically extracted result as a result of both the number of the extracted circularIt appeared. Evaluate the source image and video processing, and video to qualitative evaluation by gross were processed video image is shown excellent results. If the evaluators in order to minimize the errors of subjective judgment based on the results of the above should be done with a quantitative evaluation and qualitative evaluation utilizes a computerized assessment program is considered that further evaluation be made more efficient.

Wavelet Thresholding Techniques to Support Multi-Scale Decomposition for Financial Forecasting Systems

  • Shin, Taeksoo;Han, Ingoo
    • Proceedings of the Korea Database Society Conference
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    • 1999.06a
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    • pp.175-186
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    • 1999
  • Detecting the features of significant patterns from their own historical data is so much crucial to good performance specially in time-series forecasting. Recently, a new data filtering method (or multi-scale decomposition) such as wavelet analysis is considered more useful for handling the time-series that contain strong quasi-cyclical components than other methods. The reason is that wavelet analysis theoretically makes much better local information according to different time intervals from the filtered data. Wavelets can process information effectively at different scales. This implies inherent support fer multiresolution analysis, which correlates with time series that exhibit self-similar behavior across different time scales. The specific local properties of wavelets can for example be particularly useful to describe signals with sharp spiky, discontinuous or fractal structure in financial markets based on chaos theory and also allows the removal of noise-dependent high frequencies, while conserving the signal bearing high frequency terms of the signal. To date, the existing studies related to wavelet analysis are increasingly being applied to many different fields. In this study, we focus on several wavelet thresholding criteria or techniques to support multi-signal decomposition methods for financial time series forecasting and apply to forecast Korean Won / U.S. Dollar currency market as a case study. One of the most important problems that has to be solved with the application of the filtering is the correct choice of the filter types and the filter parameters. If the threshold is too small or too large then the wavelet shrinkage estimator will tend to overfit or underfit the data. It is often selected arbitrarily or by adopting a certain theoretical or statistical criteria. Recently, new and versatile techniques have been introduced related to that problem. Our study is to analyze thresholding or filtering methods based on wavelet analysis that use multi-signal decomposition algorithms within the neural network architectures specially in complex financial markets. Secondly, through the comparison with different filtering techniques' results we introduce the present different filtering criteria of wavelet analysis to support the neural network learning optimization and analyze the critical issues related to the optimal filter design problems in wavelet analysis. That is, those issues include finding the optimal filter parameter to extract significant input features for the forecasting model. Finally, from existing theory or experimental viewpoint concerning the criteria of wavelets thresholding parameters we propose the design of the optimal wavelet for representing a given signal useful in forecasting models, specially a well known neural network models.

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Improvement of the performance of SPPCM using mixed polarized beam and cylindrical lens (혼합 편광빔과 원주면렌즈를 사용한 SPPCM의 성능 개선)

  • Yi, Eun-Hyeong;Kim, Seong-Wan;Kim, Cheol-Su;Kim, Jong-Yun;Lee, Seung-Hee;Lee, Soo-Joong
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.9
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    • pp.56-63
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    • 1999
  • Conventional method to improve the response time of the Cat-SPPCM was to increase fanning beam using cylindrical lens. But, in this case the temporal instability of this SPPCM is increased, and fanning beam plays a role as noise, so that it decreases the reflectivity. Thus, fanning beam must be controlled to improve the properties of SPPCM. In this paper, we propose the method to increase the reflectivity of SPPCM and decrease the response time by focusing line-shaped input beam into photorefractive crystal using cylindrical lens and decrease the temporal instability of output beam by using mixed-polarized beam instead of simple extraordinary polarized beam. Optical experiments show that the reflectivity of proposed SPPCM is increased twice and the response time is reduced by 15 times. Also, we observed that the temporal instability of SPPCM is reduced when the polarization angle of the mixed-polarized beam is between $10^{\circ}$ and $30^{\circ}$ . We used a $45^{\circ}-cut\;BaTiO_3$ crystal which has high electro-optical coefficients in optical experiments.

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