• 한국환경복원기술학회지
• /
• 제7권1호
• /
• pp.85-96
• /
• 2004

The purpose of this study is to present the legal object in the related legislation taking the present condition of the domestic laws and the leading cases connected with ecological restoration materials and analyzing their properties according to the analytic standards which are legal class and ecological restoration material items, the present condition by the field of ecological restoration business, interrelationship between the law and the leading cases, comparison of the domestic laws with the foreign regulations. The results of this study are as follows; 1) Detailed enforcement regulation(36.5% of totals), enforcement regulation(32.4%) and law(31.1%) as legal class of the domestic legislation relating to ecological restoration materials are in the order of frequency that shows the little strong frequency at low-ranking class. By items, the number of legislation relating to planting material holds about majority, next to it, stone material, soil material and wood material are in the order of frequency. 2) By the field of ecological restoration business, legislation relating to administration forms the highest frequency(36.3% of totals), next to it, material properties(23.4%), plan design(13.0%) are in the order of frequency. 3) For the number of the leading cases by items of ecological restoration materials, those are, for the most part, them relating to planting material(93.8% of totals). The number of legislation relating to planting material forms the highest frequency at laws and the leading cases in common. 4) The domestic legislation connected with ecological restoration materials is mainly to be in legal class of the positive law, on the contrary, a foreign country has legislation widely consisted of laws, ordinances and other general regulations. Some foreign country legislated the topsoil conservation act, but not to domestic. The result of this study will be applied to legislature and court as reference materials, and to the public and public officer as a means of an understanding of ecological restoration materials.

• Journal of information and communication convergence engineering
• /
• 제7권2호
• /
• pp.231-234
• /
• 2009

Speckle noise reduction for power Doppler ventricle coherent image for restoration and enhancement using Fast Wavelet Transform with multi-thresholding and multi-filtering on the each subbands is presented. Fast Wavelet Transform divides into low frequency component image to high frequency component image to be multi-resolved. Speckle noise is located on high frequency component in multi-resolution image mainly. A Doppler ventricle image is transformed and inversed with separated threshold function and filtering from low to high resolved images for restoration to utilize visualization for ventricle diagnosis. The experimental result shows that the proposed method has better performance in comparison with the conventional method.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 춘계학술대회
• /
• pp.156-159
• /
• 2009

Speckle noise reduction for 3D power doppler ventricle coherent image for restoration and enhancement using wavelet packet transform with separated thresholding is presented. Wavelet Packet Transform divide into low frequency component image to high frequency component image to be multi-resolved. speckle noise is located on high frequency component in multiresolution image mainly. A ventricle image is transformed and inversed with separated threshold function from low to high resolved images for restoration to be utilize visualization for ventricle diagnosis. The experimental result shows that the proposed method has better performance in comparison with the conventional method.

• 전기학회논문지
• /
• 제61권11호
• /
• pp.1584-1589
• /
• 2012

The grid-interconnected microgrid can be able to operate with and without the utility microgrid to supply electricity. when the microgrid operates in grid-connected mode, the frequency of the microgrid synchronizes with the system frequency. In this case, the frequency of the microgrid has small variation which is able to change the output of distributed generation with a droop controller. Thus, the small variation of frequency can make the distributed generation generate unnecessary electricity consistently. In this paper, we propose a frequency droop control with a dead band so as to prevent the distributed generations from generating unnecessary output while in grid-interconnected mode. In addition, a distributed generation can have a restoration control to restore the frequency changed by a droop control as a rated frequency. Also, we state the problem of restoration control with a dead band, and propose its solution when the microgrid operates in stand alone mode. We simulate the proposed droop control using PSCAD/EMTDC to verify the validity of the control.

• 한국환경생태학회지
• /
• 제18권1호
• /
• pp.61-74
• /
• 2004

본 연구는 2000년 일부 구간이 자연형 하천으로 복원된 불광천을 대상으로 하여 한 하천 내에 정비방식이 다른 직강화 하천구간과 자연형 하천복원구간으로 구분하여 식물상 및 식물종의 출현빈도를 비교 분석하였다. 조사는 2003년 5월과 8-9월에 걸쳐 이루어졌으며, 식물상은 하천의 양안에 출현한 모든 식물을 동정하여 정리하였고. 식생은 200m를 기준으로 하여 Belt-transect 방법을 이용하였다. 2003년 5월 및 8-9월은 직강화 하천구간에서는 33과 73속 88종의 식물이 출현하였고. 자연형 하천복원구간은 36과 76속 90종의 식물이 출현하였다. 귀화율 (Naturalized Index：Nl)은 직강화 하천구간은 22.7%, 자연형 하천복원구간은 21.1%였고, 도시화지수 (Urbanization Index：Ul)는 직강화 하천구간이 7.8%. 자연형 하천복원구간이 74%로 직강화 하천구간이 자연형 하천복원구간보다 약간 높았다. Belt-transect 조사법에 의한 식물종 출현빈도 결과는 직강화 하천구간에서는 하안에는 여뀌와 환삼덩굴이 제방에는 망초와 큰비짜루국화가 가장 높은 출현빈도를 보였다. 이에 반해 자연형 하천복원구간에서는 하안에는 갯버들, 여뀌, 소리쟁이. 환삼덩굴이, 제방에는 망초와 큰비짜루국화가 가장 높은 출현빈도를 보였다. 즉 직강화 하천구간과 자연형 하천복원 구간은 제방에는 구간에 따른 차이가 없고, 하안의 경우에는 자연형 하천복원구간에 도입된 갯버들이 출현하여 차별을 보였다.

• IEIE Transactions on Smart Processing and Computing
• /
• 제3권2호
• /
• pp.41-51
• /
• 2014

This paper describes a method to estimate the noise power using the minimum statistics approach, which was originally proposed for audio processing. The proposed minimum statistics-based method separates a noisy image into multiple frequency bands using the three-level discrete wavelet transform. By assuming that the output of the high-pass filter contains both signal detail and noise, the proposed algorithm extracts the region of pure noise from the high frequency band using an appropriate threshold. The region of pure noise, which is free from the signal detail part and the DC component, is well suited for minimum statistics condition, where the noise power can be extracted easily. The proposed algorithm reduces the computational load significantly through the use of a simple processing architecture without iteration with an estimation accuracy greater than 90% for strong noise at 0 to 40dB SNR of the input image. Furthermore, the well restored image can be obtained using the estimated noise power information in parametric image restoration algorithms, such as the classical parametric Wiener or ForWaRD image restoration filters. The experimental results show that the proposed algorithm can estimate the noise power accurately, and is particularly suitable for fast, low-cost image restoration or enhancement applications.

• 정보저장시스템학회논문집
• /
• 제5권1호
• /
• pp.36-40
• /
• 2009

We describe the experimental realization of image system using wavefront coding in 3-Mega pixel mobile phone camera. We designed aspheric lens to extend the depth of field (DOF) using wavefront coding. In addition, through the aspheric lens and lens barrel manufacturing, we obtained a raw image from a camera module. In our method, the acquired images are restored in the spatial frequency domain using the proposed filter and the spatial frequency response (SFR) is calculated. The proposed filters are composed of image denoising filter using low band pass filter in frequency domain and restoration filter for image restoration. Finally, we achieve an enhanced image by super-resolution image processing. Visual examples are given to demonstrate the performance of the proposed filter.

• 한국산업정보학회:학술대회논문집
• /
• 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
• /
• pp.91-101
• /
• 1997

The demand for handling images in digital form has increased dramatically in recent years. Digital image compression is required to store and transmit mass information in different from general information. JPEG(Joint Photographic Experts Group) committee founded by CCITT and ISO is define the still-image standard compression/restoration algorithm. JPEG is proposed the standard of grayscale and color still-image compression/restoration. In the image quality, JPEG is applicable to the various applications in which compression is able to from 1/10 to 1/50 without the visible obstacle. In this paper, we proposed that the proposed method enhance the compression ratio which is reducing the higher frequency in order to increasing the spatial redundancy in the image. The proposed method is using the low pass filter in order to reducing the higher frequency. The low-pass filters are using the median filter and convolution filter in the spatial domain, FFT filter in the frequency domain. We acquired the additive compression ratio reducing the higher frequency using the low-pass filter.

• 대한전자공학회논문지
• /
• 제21권2호
• /
• pp.54-60
• /
• 1984

Hunt가 제안한 restoration방법은 한정조건(constraint)을 만족하는 적정한 y값을 찾음으로써 얻어진다. 본 논문에서는 이러한 Hunt방법에 의한 restoration 필터에 인버스 필터의 효과를 첨가하여 얻어지는 새로운 image restoration 방법을 제시하였다. 따라서 복원된 영상(restored image)을 구하기 위한 적정액 γ가 유일하게 결정되는 Hunt의 방법에 비해 인버스 필터 효과의 정도에 따라 한정조건을 만족하는 적정치 γ를 새롭게 결정함으로써 얻어지는 복원된 영상에서 고주파 성분이 강조되는 효과를 볼 수 있다. 본 논문에서는 인버스 필터 효과의 정도를 나타내는 α를 변화시켜 가며 restoration된 결과와 α가 0인 경우에 해당하는 Hunt의 방법에 의해 restoration되어진 결과를 비교. 검토하였다.

• 대한토목학회논문집
• /
• 제33권4호
• /
• pp.1361-1375
• /
• 2013

Lee et al. (2011)이 제시한 목감천 유역의 하천복원 설계절차에 근거하여 수리구조물의 설계와 관련 있는 설계홍수량을 산정에 있어 비정상성을 고려하여 산정하였다. 본 연구의 목적은 목감천 유역에서 비정상성을 고려한 새로운 설계홍수량을 제안하기 위함이다. 설계홍수량 산정방법인 설계-호우단위도법과 직접 홍수빈도해석법을 적용하였으며, 각각의 방법에 사용되는 빈도분석은 NCAR (National Center for Atmospheric Research)에서 개발된 extRemes 모형을 통하여 비정상성을 고려하였다. 직접 홍수빈도해석의 방법은 유량으로부터 직접 빈도해석을 수행한다는 점에서 신뢰성이 기대되지만, 설계-호우단위도법보다 다소 과소 추정되었다. 따라서 가장 크게 산정된 설계호우-단위도법의 100년 빈도 설계홍수량을 목감천 유역의 설계홍수량으로 결정하였다.