• Title/Summary/Keyword: 선택과 제거

Search Result 1,492, Processing Time 0.029 seconds

Building Roof Reconstruction in Remote Sensing Image using Line Segment Extraction and Grouping (선소의 추출과 그룹화를 이용한 원격탐사영상에서 건물 지붕의 복원)

  • 예철수;전승헌;이호영;이쾌희
    • Korean Journal of Remote Sensing
    • /
    • v.19 no.2
    • /
    • pp.159-169
    • /
    • 2003
  • This paper presents a method for automatic 3-d building reconstruction using high resolution aerial imagery. First, by using edge preserving filtering, noise is eliminated and then images are segmented by watershed algorithm, which preserves location of edge pixels. To extract line segments between control points from boundary of each region, we calculate curvature of each pixel on the boundary and then find the control points. Line segment linking is performed according to direction and length of line segments and the location of line segments is adjusted using gradient magnitudes of all pixels of the line segment. Coplanar grouping and pplygonal patch formation are performed per region by selecting 3-d line segments that are matched using epipolar geometry and flight information. The algorithm has been applied to high resolution aerial images and the results show accurate 3D building reconstruction.

Ethical Event of Responsibility in Nietzsche's Philosophy (니체철학에서 책임의 문제)

  • Yang, Dae-jong
    • Journal of Korean Philosophical Society
    • /
    • v.139
    • /
    • pp.105-131
    • /
    • 2016
  • The notion of responsibility, which has now gained a firm foothold as one of the fundamental notions of philosophy and its neighboring disciplines, became the subject of philosophical enquiry only in the 19th century by Kierkegaard, who delved into the morality of critical self-awareness in ethical responsibility of the absolute self; and Nietzsche, who put emphasis on the responsibility of the sovereign self in coping with the problems of the future. Nietzsche is the first philosopher who took issue with the diminishment (Verkleinerung) of humanity-what he called human being's greatest disease-that swept Europe at that time. Concerns about Europe's future were the key movens of Nietzsche's philosophy revolving around the advent of nihilism in Europe and its solutions. He prepared alternative solutions in deep awareness that the ethics of good and evil firmly rooted in the traditional metaphysics and Christianity would not even catch the depth and breadth of the big problem of globalization brought about by modernism, let alone solve it. Nietzsche devoted his whole life to disseminating the knowledge that the future of humankind depends on removing these old ethics. This article traces Nietzsche's reflections on the ethical event of responsibility and provides an overview of the purview and scope contained in the meaning covered by the notion of responsibility in his philosophy beyond common norms and values.

Time Series Analysis of Agricultural Reservoir Water Level Data for Abnormal Behavior Detection (농업용 저수지 이상거동 탐지를 위한 시계열 수위자료 특성 분석)

  • Lee, Sung Hack;Lee, Sang Hyun;Hong, Min Ki;Cho, Jin Young
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2015.05a
    • /
    • pp.275-275
    • /
    • 2015
  • 최근 기후변화에 따른 극한 강우사상의 증가로 인하여 농업용 저수지의 재해 위험도가 증가하고 있는 추세이며, 사고가 발생할 때 마다 파손/붕괴된 시설물을 보수하는 대응형 유지관리체계에서 벗어나 기반시설의 성능과 생애주기 등을 고려하여 재해 발생을 사전에 예보 및 경보를 알릴 수 있는 예방적 관리체계로의 전환이 필요하다. 한국농어촌공사는 전국 1,500개 저수지에서 10분 단위 수위자료를 측정하고 있으며, 이를 분석하여 재해예방에 활용할 수 있는 기반이 조성되어 있으나 이에 대한 관리가 이루어지지 않고 있고 수집된 자료를 활용하여 재해 징후를 분석할 수 있는 재해 예방적 분석기술이 마련되어 있지 않은 실정이다. 본 연구에서는 농업용 저수지 수위자료를 이용한 저수지 이상거동을 판별하기 위하여 전국 34개 한국농어촌공사 관할 저수의 시계열 수위자료의 특성(Feature)을 분석하고자 한다. 시계열 자료의 시계열 특성을 분석하기 위하여 한국농어촌공사 관할의 전국 34개 저수지를 선정하여 분석을 실시하였다. 대상저수지는 지역별, 저수용량, 안정등급, 붕괴발생, 1개 지사관할 저수지로 각각 구분하여 선정하였으며, 각 저수지의 수위 측정기간(최소 5개년)에 대한 자료를 수집하였다. 농업용 저수지의 시계열 수위 자료의 특성을 분석하기 위하여 자료의 전처리를 수행하였다. 자료의 전처리는 시계열 수위자료의 잡음 특성, 기상자료 관련 변동특성 등 분류(Classification)에 영향을 미치는 노이즈 요소를 제거하는 과정이다. 전처리과정을 거친 자료는 특징(Feature) 추출 과정을 거치게 되고, 추출된 특징의 적합성에 따라 분류 알고리듬 성능에 많은 영향을 미친다. 따라서 시계열 자료의 특성을 파악하고 특징을 추출하는 것은 이상치 탐지에 있어 매우 중요한 과정이다. 본 연구에서는 시계열 자료 특징 추출 방법으로 물리적인 한계치, 확률적인 문턱값(Threshold), 시계열 패턴, 주변 저수지와의 시계열 상관분석 등을 적용하였으며, 이를 데이터베이스로 구축하여 이후 분류알고리듬 학습에 적용하여 정상치와 이상치를 판별하는데 이용될 수 있도록 하였다. 따라서 본 연구에서 제시되는 농업용 저수지의 시계열 특성은 다양한 분류알고리듬에 적용할 수 있으며, 이를 통하여 저수지 이상거동 판별을 위한 최적을 분류알고리듬의 선택에 도움이 될 것이다.

  • PDF

A Review on Lithium Recovery by Membrane Process (멤브레인 공정에 의한 리튬 회수에 대한 총설)

  • Kim, Esther;Patel, Rajkumar
    • Membrane Journal
    • /
    • v.31 no.5
    • /
    • pp.315-326
    • /
    • 2021
  • Lithium ion battery (LIB) demands increase every year globally to reduce the burden on fossil fuels. LIBs are used in electric vehicles, stationary storage systems and various other applications. Lithium is available in seawater, salt lakes, and brines and its extraction using environmentally friendly and inexpensive methods will greatly relieve the pressure in lithium mining. Membrane separation processes, mainly nanofiltration (NF), is an effective way for the separation of lithium metal from solutions. Electrodialysis and electrolysis are other separation processes used for lithium separation. The process of reverse osmosis (RO) is already a well-established method for the desalination of seawater; therefore, modifying RO membranes to target lithium metals is an excellent alternative method in which the only bottleneck is the interfering presence of other metal elements in the solution. Selectively removing lithium by finding or developing suitable NF membranes can be challenging, but it is nonetheless an exciting area of research. This review discusses in detail about lithium recovery via nanofiltration, electrodialysis, electrolysis and other processes.

An Adaptive Motion Vector Estimation Method for Multi-view Video Coding Based on Spatio-temporal Correlations among Motion Vectors (움직임 벡터들의 시·공간적 상관성을 이용한 다시점 비디오 부호화를 위한 적응적 움직임 벡터 추정 기법)

  • Yoon, Hyo-Sun;Kim, Mi-Young
    • The Journal of the Korea Contents Association
    • /
    • v.18 no.12
    • /
    • pp.35-45
    • /
    • 2018
  • Motion Estimation(ME) has been developed to reduce the redundant data in digital video signal. ME is an important part of video encoding system, However, it requires huge computational complexity of the encoder part, and fast motion search methods have been proposed to reduce huge complexity. Multi- view video is obtained by capturing on a three-dimensional scene with many cameras at different positions and its complexity increases in proportion to the number of cameras. In this paper, we proposed an efficient motion method which chooses a search pattern adaptively by using the temporal-spatial correlation of the block and the characteristics of the block. Experiment results show that the computational complexity reduction of the proposed method over TZ search method and FS method can be up to 70~75% and 99% respectively while keeping similar image quality and bit rates.

Simultaneous Simplification of Multiple Triangle Meshes for Blend Shape (블렌드쉐입을 위한 다수 삼각 메쉬의 동시 단순화 기법)

  • Park, Jung-Ho;Kim, Jongyong;Song, Jonghun;Park, Sanghun;Yoon, Seung-Hyun
    • Journal of the Korea Computer Graphics Society
    • /
    • v.25 no.3
    • /
    • pp.75-83
    • /
    • 2019
  • In this paper we present a new technique for simultaneously simplifying N triangule meshes with the same number of vertices and the same connectivities. Applying the existing simplification technique to each of the N triangule mesh creates a simplified mesh with the same number of vertices but different connectivities. These limits make it difficult to construct a simplified blend-shape model in a high-resolution blend-shape model. The technique presented in this paper takes into account the N meshes simultaneously and performs simplification by selecting an edge with minimal removal cost. Thus, the N simplified meshes generated as a result of the simplification retain the same number of vertices and the same connectivities. The efficiency and effectiveness of the proposed technique is demonstrated by applying simultaneous simplification technique to multiple triangle meshes.

Background Concentration and Contamination Assessment of Heavy Metals in Korean Coastal Sediments (한반도 연안 퇴적물의 중금속 배경농도 및 오염도 평가)

  • WOO, JUNSIK;LEE, HYOJIN;PARK, JONGKYU;PARK, KYOUNGKYU;CHO, DONGJIN;JANG, DONGJUN;PARK, SOJUNG;CHOI, MANSIK;YOO, JEONGKYU
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.24 no.1
    • /
    • pp.64-78
    • /
    • 2019
  • The background concentrations of heavy metals in Korean coastal sediments were estimated using heavy metal data for 495 sediments obtained from 'National Marine Ecosystem Survey (Coastal ecosystem) in 2016-2017' and the extent of contamination was assessed. Al, Cs, and Li are chosen as appropriate indicators for sediment grain size. In the relationships between heavy metal and indicators concentrations, the lowest slope data were selected through the outlier removal and residual analysis, and the background concentrations were presented as a linear regression line between metal and indicator. Comparing the previous studies for the background concentrations of heavy metals in Korean coastal sediments, concentration levels were generally consistent but those for As and Cd were presented for the first time, and the background concentration using Li as the indicator was presented for the first time.

A Study on Kernel Size Adaptation for Correntropy-based Learning Algorithms (코렌트로피 기반 학습 알고리듬의 커널 사이즈에 관한 연구)

  • Kim, Namyong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.22 no.2
    • /
    • pp.714-720
    • /
    • 2021
  • The ITL (information theoretic learning) based on the kernel density estimation method that has successfully been applied to machine learning and signal processing applications has a drawback of severe sensitiveness in choosing proper kernel sizes. For the maximization of correntropy criterion (MCC) as one of the ITL-type criteria, several methods of adapting the remaining kernel size ( ) after removing the term have been studied. In this paper, it is shown that the main cause of sensitivity in choosing the kernel size derives from the term and that the adaptive adjustment of in the remaining terms leads to approach the absolute value of error, which prevents the weight adjustment from continuing. Thus, it is proposed that choosing an appropriate constant as the kernel size for the remaining terms is more effective. In addition, the experiment results when compared to the conventional algorithm show that the proposed method enhances learning performance by about 2dB of steady state MSE with the same convergence rate. In an experiment for channel models, the proposed method enhances performance by 4 dB so that the proposed method is more suitable for more complex or inferior conditions.

Reaction Mechanism of Low Temperature NH3 SCR over MnOx/Sewage Sludge Char (MnOx/Sewage Sludge Char를 이용한 저온 NH3 SCR의 반응 메커니즘)

  • Cha, Jin-Sun;Park, Young-Kwon;Park, Sung Hoon;Jeon, Jong-Ki
    • Applied Chemistry for Engineering
    • /
    • v.22 no.3
    • /
    • pp.308-311
    • /
    • 2011
  • The reaction mechanism of selective catalytic reduction of NOx over sewage sludge char impregnated with MnOx using $NH_3$ as the reducing agent was investigated. The active Mn phase was shown to be $Mn_3O_4$ from the XRD analysis. Adsorption was the dominant NOx removal mechanism at low temperatures below $150^{\circ}C$ although reduction reaction also contributed partly to the NOx removal at $100{\sim}150^{\circ}C$. The reaction rate constants of NOx removal over non-impregnated and MnOx-impregnated active chars were compared based on experimental results. The MnOx-impregnated char was shown to have a higher reaction rate constant and a higher NOx removal efficiency due to a higher collision coefficient and a lower activation energy. The activation energy for both chars was shown to be relatively low (10~12 kJ/mol) under the experimental conditions of this study.

Matching Performance-Based Comparative Study of Fingerprint Sample Quality Measures (매칭성능 기반의 지문샘플 품질측정방법에 관한 비교연구)

  • Jin, Chang-Long;Kim, Hak-Il;Elliott, Stephen
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.19 no.3
    • /
    • pp.11-25
    • /
    • 2009
  • Fingerprint sample quality is one of major factors influencing the matching performance of fingerprint recognition systems. The error rates of fingerprint recognition systems can be decreased significantly by removing poor quality fingerprints. The purpose of this paper is to assess the effectiveness of individual sample quality measures on the performance of minutiae-based fingerprint recognition algorithms. Initially, the authors examined the various factors that influenced the matching performance of the minutiae-based fingerprint recognition algorithms. Then, the existing measures for fingerprint sample quality were studied and the more effective quality measures were selected and compared with two image quality software packages, (NFIQ from NIST, and QualityCheck from Aware Inc.) in terms of matching performance of a commercial fingerprint matcher (Verifinger 5.0 from Neurotechnologija). The experimental results over various Fingerprint Verification Competition (FVC) datasets show that even a single sample quality measure can enhance the matching performance effectively.