• Sleep Medicine and Psychophysiology
• /
• v.7 no.2
• /
• pp.102-108
• /
• 2000

Objectives: Parkinson's disease (PD) patients may experience fluent mobility upon awakening from a night's sleep, which is called sleep benefit (SB). Although SB is a phenomenon closely associated with sleep, sleep features of PD are not well characterized. The objectives of this study were, first, to investigate if there are any clinical characteristic features between patients with SB and without SB (NSB), and second, to examine if SB patients are associated with any specific sleep variables compared with NSB patients. Methods: Thirty-three PD patients (14 men and 19 women) participated in this study. All subjects were interviewed to examine whether or not they had SB and overnight polysomnography was performed at the sleep center. Various clinical variables were collected through medical record review. Results: The 331 PD patients were divided into 16 SB group (48.5%) and 17 NSB group (51.5%). SB patients were younger (p<0.02), had higher sleep efficiency (p<0.05), and showed shortened sleep latency (p<0.02) as compared with NSB patients. However, no difference was found between SB and NSB with respect to gender, duration or stage of PD, antiparkinsonian medications prescribed, and predominant motor symptoms. SB did not clearly relate to a specific sleep stage and other sleep variables except sleep efficiency and sleep latency. Although primary snoring was more prevalent in SB patients (p<0.05), other sleep disorders were seen with equal frequency in SB and NSB groups. Conclusion: Our results suggest that good sleep efficiency, shortened sleep latency, and age may have an effect on morning motor function (i.e., SB) in Parkinson's disease.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.22 no.9
• /
• pp.858-867
• /
• 2011

In this paper, we propose a microwave radiometer for remote sensing of oil spills on the water surface. In order to achieve the development aim of the measurement accuracy within 0.2 mm for oil slicks of 0~4 mm thickness, the requirements of the microwave radiometer and the specifications of its receiver are drawn. From these requirements and specifications, the receiver with high gain, high sensitivity is designed and implemented. The receiver has the bandwidth of 58 MHz, the system gain of 47.3 dB and the sensitivity of 0.46 K at 10.65 GHz. The processes of design and implementation of the receiver are described in this paper. The effectiveness of the proposed microwave radiometer in the measurement of oil slicks is demonstrated experimentally. The results show the microwave radiometer can detect the oil slicks for 0~5 mm thickness within the accuracy of 0.13 mm successfully.

• Proceedings of the ESK Conference
• /
• 1997.10a
• /
• pp.381-385
• /
• 1997

수면생리신호는 ${\mu}V ~ {\mu}V$ 급으로서 미소하므로 고이득 증폭기를 이용하여 기록하는데 이때 외부에서의 전기적 잡음이 혼입된 경우 그 잡음까지 기록되어 기록 파형으로 부터의 수면단계 해석에 오류를 초래한다. 일반적으로 수면기록장치에는 주관심 주파수대역이 낮으므로 하드웨어에서 기본적으로 저역필터링을 수행할뿐아니라 소프트웨어에서 전원잡음을 필터링하는 기능을 제공한다. 그렇지만 이러한 필터링에도 불구하고 실제에는 예기치 못하는 전기적 잡음이 혼입되어 있을 수 있으므로 본 연구에서는 Medilog SAC847(Sleeping Analysing Computer) 다원수면기록장치(Polysomnograph)를 이용하여 수면생리신호들을 측정한 뒤 SAC847 본체에 기록 저장된 raw signal을 자체 제작한 Data Acquisition System으로 읽어들여 Matlab 으로 FFT 시켜본 결과 여전히 전원잡음이 관측되어 60 Hz notch 필터를 설계하여 완전히 제거할 수 있었다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.9
• /
• pp.1107-1115
• /
• 2012

This paper presents the development processes of a microwave radiometer for remote sensing of water surface temperature. Achieving the measurement accuracy within $2^{\circ}C$ for water surface temperature of $5{\sim}30^{\circ}C$, the requirements and specifications of the microwave radiometer and its receiver are drawn. The receiver with high gain, high sensitivity is designed and implemented. The receiver has the bandwidth of 50 MHz, the system gain of 45.2 dB and the sensitivity of 0.56K at 5.02 GHz. The effectiveness of the developed microwave radiometer in the measurement of water surface temperature is demonstrated experimentally. The results show the microwave radiometer can detect water surface temperature for $7.5{\sim}18^{\circ}C$ within the accuracy of $0.45^{\circ}C$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.24 no.9
• /
• pp.900-907
• /
• 2013

The development processes of a L-band microwave radiometer for remote sensing of water surface salinity are described in this paper. Achieving the development aim of the measurement accuracy within 2 psu for water surface salinity of 0~40 psu, the requirements and specifications of the microwave radiometer and its receiver are drawn. The receiver with high gain, high sensitivity is designed and implemented to satisfy these requirements and specifications. The receiver has the bandwidth of 45 MHz, the system gain of 47 dB and the sensitivity of 0.41 K at 1,390 MHz. The effectiveness of the developed L-band microwave radiometer for remote sensing of water surface salinity is demonstrated experimentally. The results show the microwave radiometer can detect water surface salinity for 10~28 psu within the accuracy of 1.4 psu.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.12B
• /
• pp.1426-1434
• /
• 2009

RFID/USN is considered as a key convergence technology in future ubiquitous network. In RFID/USN, the power saving issue receives a great attention due to limited battery lifetime of sensor node. In this paper, we propose a new power saving algorithm, which takes advantage of long-term sleep period. To provide a full network connectivity and balance the battery consumption among sensor nodes, the proposed algorithm intelligently selects the long-term sleep sensor nodes. With mathematical analysis and simulations, we prove that the proposed algorithm can significantly reduce the power consumption of sensor nodes as compared to existing algorithms.

• Korean Journal of Psychosomatic Medicine
• /
• v.6 no.1
• /
• pp.85-89
• /
• 1998

Psychogenic cough is barky, croupy, and explosive and disappears during sleep, and is not affected by antitussive drugs. Physical and radiological examinations of the respiratory tract and other routine laboratory test are normal. It is helpful to recognize this condition early in its course so that appropriate treatment can be instituted before iatrogenic problems resulting in multiple hospitalizations and chronic steroid use occur. We experienced two child and adolescent cases that showing typical psychogenic cough so reported it with the literatures review.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.1
• /
• pp.103-108
• /
• 2016

In communication systems the solution of the problem of maximizing the mutual information between the input and output of a channel composed of several subchannels under total power constraint has a waterfilling structure. OFDM and MIMO can be decomposed into parallel subchannels with CSI. Waterfilling solves the problem of optimal power allocation to these subchannels to achieve the rate approaching the channel capacity under total power constraint. In waterfilling, more power is alloted to good channels(high SNR) and less or no power to bad channels to increase the rate of good channels, resulting in channel capacity. Waterfilling finds the exact water level satisfying the power constraint employing an iterative algorithm to estimate and update the water level. In this process computation of partial sums of inverse of square of subchannel gain is repeatedly required. In this paper we reduced the computation time of waterfilling algorithm by replacing the partial sum computation with reference to an array which contains the precomputed partial sums in initialization phase.