• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 춘계학술발표회논문집
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• pp.491-500
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• 2004

As the applications of 3D GIS rapidly increase, the need for acquisition and continuos update of urban models is increasingly emphasized. Particularly, building models has been considered as the most crucial component of urban models. Many researchers thus have focused on building extraction from mainly aerial photos or airborne LIDAR data but so far mostly failed to achieve satisfactory results in terms of both completeness and precision because of the intrinsic limitation of the sensory data themselves. Therefore, instead of the airborne sensors, we utilize a terrestrial LIDAR to generate precise and complete building models. This paper presents the overview of the sensors for data acquisition, describes data processing methods for building modelling from the acquired data and summerizes the experimental results.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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• pp.343-346
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• 2000

This paper presents a filter bank designed for the multi-channel audio equalizer. A time-shared multiplier is also proposed to implement the equalizer with a minimum number of gates when it is synthesized with ASIC or FPGA. Further reduction of the number of required gates is achieved by designing the multiplier based on a cascaded sequential circuit utilizing partial multiplications. The equalizer is realized with FPGA and its real-time operation verifies the reliability and high fidelity of the designed system.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.199-204
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• 2006

Airborne LIDAR systems have been increasingly used for various applications as an effective surveying mean that can be complementary or alternative to the traditional one based on aerial photos. A LIDAR system is a multi-sensor system consisting of GPS, INS, and a laser scanner and hence the errors associated with the LIDAR data can be significantly affected by not only the errors associated with each individual sensor but also the errors involved in combining these sensors. The analysis about these errors have been performed by some researchers but yet insufficient so that the results can be critically contributed to performing accurate calibration of LIDAR data. In this study, we thus analyze these error sources, derive their mathematical models and perform the sensitivity analysis to assess how significantly each error affects the LIDAR data. The results from this sensitivity analysis in particular can be effectively used to determine the main parameters modelling the systematic errors associated with the LIDAR data for their calibration.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.223-228
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• 2006

Monitoring structures is important to maintain the safety and serviceability of the structures. The maximum displacement in the structure should be precisely and frequently monitored because it is a direct assessment index indicating its stiffness. However, no practical method has been developed to monitor such displacement precisely, particularly for high-rise buildings and long span bridges because they cannot be easily accessible. To overcome such difficult accessibility, we propose to use a LIDAR system that remotely samples the surface of an object using laser pulses and generates the coordinates of numerous points on the surface. By analyzing the LIDAR points sampled from the surfaces of a deformed structure, we can precisely determine the displacement of the structure. In this study, we thus develop a novel method based the LIDAR system and perform an indoor experiment to prove its performance. This experimental results strongly supports that the displacement measurement using the LIDAR system are enough accurate to be used for structural analyses.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.457-462
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• 2006

Coastline has been considered as fundamental geographic information of a nation. Recently, the coastlines of higher resolution and accuracy with less update period ever than before are increasingly required. This requirement cannot be easily satisfied with the most traditional methods based on field survey such as leveling or GPS measurements. The newly developed airborne LIDAR system can be used as a promising alternative since it rapidly acquire numerous three-dimensional points densely sampled from the terrain around the coastline. Hence, in this study we developed a nearly automatic method to extract the coastline from LIDAR data and applied it to real data to verify its performance. From the comparison of the extracted coastlines with those from a digital map, we conclude that the proposed method can provide more accurate and precise lines.

• 한국통신학회논문지
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• 제27권8C호
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• pp.812-818
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• 2002

반도체 기술과 멀티기디어 통신기술이 발달하면서 고품위의 영상과 다중 채널의 오디오에 관심을 갖게되었다. 특히 DVD 시장의 급성장으로 인하여 고품질의 영상 및 오디오 필요성이 중요한 기술로 대두되었다. MPEG-Audio 표준안은 어떠한 비트율도 지원한다. 본 논문에서는 MPEG-Audio의 핵심부분인 필터부분을 DALUT (Distributed Arithmetic Look-Up Table)방식을 사용하여 FPGA(Field Programmable Gate Array)에 구현하였다. 고속 필터를 설계하기 위해서 승산기 대신에 DALUT를 사용하였으며 최소 10㎒에서 최대 30㎒ 사이에서 동작한다. 본 논문의 설계는 모두 VHDL로 구현하였으며, 알고리즘 검증은 C언어를 사용하였다. VHDL의 시뮬레이션은 ALDEC사의 Active-HDL5.1과 Synopsys사의 vhdlsim을 사용하였고, 합성은 Synopsys사의 design-analyzer를 사용하였다. 타겟 라이브러리는 XILINX사의 XC4010E, XC4020EX, XC4052XL을 사용하였으며, P＆R 툴은 XACT Ml.4를 사용하였다.

• 대한임베디드공학회논문지
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• 제11권5호
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• pp.267-276
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• 2016

Human detection technologies are widely used in smart homes and autonomous vehicles. However, in order to detect human, autonomous vehicle researchers have used a high-resolution LIDAR and smart home researchers have applied a camera with a narrow detection range. In this paper, we propose a novel method using a low-cost and low-resolution LIDAR that can detect human fast and precisely without complex learning algorithm and additional devices. In other words, human can be distinguished from objects by using a new human characteristics function which is empirically extracted from the characteristics of a human. In addition, we verified the effectiveness of the proposed algorithm through a number of experiments.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.151-158
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• 2006

Structural health monitoring is concerned with the safety and serviceability of the users of structures, especially for the case of building structures and infrastructures. When considering the safety of a structure, the maximum stress in a member due to live load, earthquake, wind, or other unexpected loadings must be checked not to exceed the stress specified in a code. It will not fail at yield, excessively large displacements will deteriorate the serviceability of a structure. To guarantee the safety and serviceability of structures, the maximum displacement in a structures must be monitored because actual displacement is a direct assessment index on its stiffness. However, no practical method has been reported to monitor the displacement, especially for the case of displacement of high-rise buildings because of not to easy accessive. In this paper, it is studied displacement measuring method of high-rise buildings using LiDAR The method is evaluated by analyzing accuracy of measured displacements for existing building.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 춘계학술대회 논문집
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• pp.333-334
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• 2000

전세계적으로 온실기체에 의한 지구온난화 문제가 대표적 환경파괴현상으로써 크게 주목받고 있는 현실이다 이러한 온난화에 기여하는 주요 인자로 $H_2O$, $CO_2$, 오존, 에어로졸 둥이 알려져 있으며, 각국에서는 이들 물질의 발생 및 순환 메커니즘 둥을 규명하기 위한 연구가 활발히 진행되고 있다. 그중 에어로졸은 산란과 흡수에 따른 방사효과가 지구온난화 영향인자 중의 하나로써 주목받고 있다. 에러로졸의 방사효과에는 태양방사를 산란.흡수하는 직접효과와 함께 구름입자의 응결 핵이 되면서 구름의 광학적 성질을 변화시키는 간접적 효과가 있다. (중략)

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2001년도 추계학술대회 논문집
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• pp.67-68
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• 2001

우리 나라가 위치한 동북아 지역은 급속한 산업 및 경제활동 증가로 세계의 주요 오염 지역으로 대두되고 있다. 특히, 중위도 편서풍대 위치한 우리 나라는 주로 3월과 4월 황사의 영향을 받고 있다. 사막에서 발생한 모래먼지는 시정을 악화시키며 이들 중 미세한 입자(0.1~10$\mu\textrm{m}$)는 산란과 흡수를 통하여 대기의 복사평형과 기후변화에 커다란 영향을 미칠 수 있다(Carlson, 1980; Duce,1980; Shaw,1980). 이러한 현상은 주로 대기 중의 미세 입자의 광산란에 기인되는 것으로 도시 지역의 에어로졸의 분포 및 화학적인 성분과 밀접한 관계를 가진다. (중략)