• 한국군사과학기술학회지
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• 제13권1호
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• pp.30-35
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• 2010

As of today, Frequency Hopping techniques are widely used for over-channel interference and anti-jamming communication systems. In this paper, analysis the performance of robustness on the focus of some general jamming channel. In FH/SS systems, usually SFH(Slow Frequency Hopping) and FFH(Fast Frequency Hopping) are took up on many special communication systems, the SFH, FFH are also combined with a channel diversity algorithm likes NED(Normalized Envelop Detection), EGC(Equal Gain Combines) and Clipped Combines to overcome jammer's attack. This paper propose Adaptive-NED and shows A-NED will be worked well than the others in the some general jamming environments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.3145-3147
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• 2000

A passive RFID system consists of reader and tag. Reader is required the filter to modulate the data from backscattering signal which is transmitted by tag. The filter in the reader consists of envelope detector, amplifier, filter, and pulse shaping circuit, In this paper, design and analysis of filter in the RFID system which is operated at l3.56MHz carrier and 70KHz backscattering signal frequency is presented and is confirmed by simulation using Pspice.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.251-258
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• 2009

Building-Integrated Photovoltaics (BIPV) is a photovoltaic (PV) technology which can be incorporated into the roofs walls of both commercial and domestic buildings to provide a source of electricity. BIPV systems can operate as a multi-functional building components, which generates electricity and serves as part of building envelope. It can be regarded as a new architectural elements, adding to the building's aesthetics. Applying PV modules on roof has an advantage over wall applications as they seem to receive more solar radiation on PV modules. There are various types of PV applications on building roofs: attached, on-top and integrated. This paper describes the classification and characteristics of PV applications on roofs.

• 대한기계학회논문집
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• 제12권6호
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• pp.1312-1319
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• 1988

본 연구에서는 임의의 내접치차를 가공하기 위한 구형호브를 설계하는데 그 목적이 있으며 GTP를 구하는 방법으로는 CAD의 envelope 이론을 도입하여 근사해법이 아닌 해석적 방법으로 GTP를 구하였으며 이는 여러 오차 해석에서도 유용하게 이용되 었다.또한 호브의 설계를 위한 전산 프로그램을 개발하여 가공하고자 하는 내접치 차의 데이터로 부터 압력각, 이두께 및 피치의 값을 수정하여 호브를 설계함과 동시에 여유면 가공량을 등을 바로 계산할 수 있도록 하였으며 이에 의한 구형 호브의 설계에 를 제시하였다.

• 한국전자파학회논문지
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• 제10권7호
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• pp.1074-1084
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• 1999

본 논문에서는 주파수 비선택적 느린 Nakagami M-분포 페이딩 채널에서 비동기 M진 FSK 시스템의 비트 오류 확률을 수신 신호의 포락선 분포에 대한 확률 분포 함수로부터 구한다. 또한 동기 M 진 FSK 시스템의 성능은 동일한 페이딩 채널에서 결합 한계(union bound)를 사용하여 이론적으로 해석된다. 그런 다음 M진 FSK신호에 대한 비트 오류 확률을 DPSK에 대한 오류 확률과 비교하여 시스템의 성능을 비교한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1483-1485
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• 2004

Photovoltaic(PV) technology is a popular part of building vocabulary. It can be used today on both existing and new buildings. Its use in the building envelope is very varied and open ways, such as roofing materials, facades, skylights and shading systems, for creative designers. So, to activate this systems demand appropriate sources of information, performance data of elements and design tools offering architects and designer. Therefore this paper describe application elements for BIPV system and then predict improvement in the generated electric power performance of balcony BIPV system.

• Journal of Astronomy and Space Sciences
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• 제19권4호
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• pp.255-262
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• 2002

We present the infrared spectra of Herbig Ae/Be stars including the Infrared Space Ob-servatory (ISO) data. To investigate the overall properties of their circumstellar dust envelope and/or disk, we combine the IR spectra with photometric data ranging from the UV through the optical into the sub-mm region. We study the general characteristics of the spectral energy distributions using simple analysis. We plot the positions on the HR-diagram to compare with the theoretical pre-main-sequence evolution tracks.

• 한국군사과학기술학회지
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• 제5권1호
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• pp.37-44
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• 2002

An echo signal in the active sonar using a high frequency is mainly formed of a specular reflection from the surface of an object along with several equivalent scatter inside, which are characterized by the spatial distribution of the highlights on the object. This thesis proposed a model in which the synthesized echo signal can be expressed as a distributed simulated target. The proposed model is obtained after composing a signal based on the movement of highlights relative to the aspect angle from the discontinuous point of an external hull with a strong reflection from a spheroid underwater target. Because the proposed algorithm includes a synthesis of the signals related to the highlight spacial distribution, it can be applied to all kinds of systems used at a short range, and similar results were obtained to the actual measured results of all reflected signals in previous literature referring to the irregular factor application of an envelope.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 춘계학술발표논문집 1부
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• pp.253-256
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• 2010

Since the amplitude of voiced fall off at about -20dB/decade, dynamic range is often compressed prior to spectral analysis so that details at weak, high frequencies may be visible. Preemphasizing the speech, either by differentiating the analog speech $s_a$(t) prior to A/D conversion or by differencing the discrete-time s(n)=$s_a$(nT), compensating for falloff at high frequencies. The most common form of preemphasis is y(n)=s(n)-As(n-1), where A typically lies between 0.9 and 1.0 and reflects the degree of pre-emphasis. In this paper, we proposed that A is adjusted at each time by measuring the slope of envelope in frequency domain.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.331-337
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• 2013

Acoustic Emission technique is widely applied to develop the early fault detection system, and the problem about a signal processing method for AE signal is mainly focused on. In the signal processing method, envelope analysis is a useful method to evaluate the bearing problems and Wavelet transform is a powerful method to detect faults occurred on rotating machinery. However, exact method for AE signal is not developed yet. Therefore, in this paper two methods which are Hilbert transform and DET for feature extraction. In addition, we evaluate the classification performance with varying the parameter from 2 to 15 for feature selection DET, 0.01 to 1.0 for the RBF kernel function of SVR, and the proposed algorithm achieved 94% classification accuracy with the parameter of the RBF 0.08, 12 feature selection.