• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.66-67
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• 2008

Most mineral resources are located in subsurface but mineral exploration starts with a step of investigation in wide-area to find evidence of buried ores. Conventional technique for exploration on wide-area as a preliminary survey is an observation using naked eyes by geologist or chemical analysis using lots of samples obtained from target area. Hyperspectral remote sensing can overcome those subjective and time consuming survey and can produce mineral resources distribution map. Precise resource map requires information of mineral distribution in a subpixellevel because mineral is distributed as rock components or narrow veins. But most hyperspectral data is composed of pixels of several meters or more than ten meters scale. We reviewed subpixel unmixing algorithms which have been used for geological field and tested detection ability with Hyperion imagery, geological map and seven spectral curves of mineral and rock specimens which were obtained from study areas.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.316-319
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• 1998

RPWM(Random Pulse Width Modulation) is a switching technique to spread the voltage and current harmonics on the wide frequency area. Using randomly changed switching frequency of the inverter, the power spectrum of the electromagnetic acoustic noise cab be spread to the wide-band area. The wide-band noise is much more comfortable and less annoying than the narrow-band one. So RPWM have been attracting an interest as an excellent method for the reduction of acoustic noise on the inverter drive system. In this paper a new RPPWM (Random Position PWM) is proposed and implemented. Each of three pulses is located randomly in each switching interval. Along with the randomization of PWM pulses, the space vector modulation is executed in the C167 microcontroller also. The experimental results show that the voltage and current harmonics were spread to wide band area and that the audible switching noise was reduced by proposed RPPWM method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.56-57
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• 2017

In recent years, new construction methods have been required to reduce the construction cost and increase the available area in an environment where construction work is frequently performed in a narrow urban area like Korea. As a result of these studies, slim floor composite beam has been suggested. Slim floor composite beam can reduce required depth because web of steel beam is embedded in the slab, so it is effective to reduce floor height and increase the available area. The purpose of this study is the floor height reduction evaluation by comparing system consisting of reinforced concrete, steel, and slim floor using square-shape steel pipe. After doing structural design for a typical plan, checked effectiveness by comparing each design plan. It is proven that slim floor composite beam can reduce required depth effectively comparing required materials of other system.

• 한국조경학회지
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• 제25권4호
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• pp.51-60
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• 1998

The purpose of this study was investigating the managers' consciousness on the interior landscape in coffee shop, the actual measurement of the space size and greenary spaces of coffee shop for grasping the actual condition of interior landscape. The coffee shop was made and object of this research was 100 cases in the center of Taegu city. The major results of actual measurement of the ratio greenary and spaces are as follows; 1. The ratio greenary spaces in the indoor plants was account for 2.06% of the coffee shop area. 2. The managers recognized that the spaces area of the interior plantscape were narrow comparison with whole spaces area about the interior landscape. 3. A major arrangement type of the interior landscape was the dispersion type. 4. A major plants used for the interior landscape were foliage plants and also most of managers prefered foliage plant. 5.Generally, managers were high interested in the interior landscape but the experience knowledge and investment in the interior landscape were not sufficient.

• 상하수도학회지
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• 제19권3호
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• pp.348-356
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• 2005

Water quality sampling surveys and continuous measurement of flow were conducted to identify wastewater flow characteristics for representative catchment of O and M treatment basins in A city. For HS-1 station representing commercial area, wastewater flow rises in the beginning of office-working hours, moves up and down within narrow range, and lasts till office-leaving hour, and falls gradually reflecting worker's returning home. However, in HS-2 station representing residential area, wastewater flow has two peaks, which are before office-going hour and after office-leaving hour. In residential area, the flow rate of weekends is higher than that of weekdays because it reflects population, being not contributed to generate wastewater during the working hours of weekdays, stay home and produce wastewater for weekends period. To determine the priority for rehabilitation of sewer system, infiltration rate was computed by dividing infiltration flow by mean diameter and total length of sewer, and HS-1 station ranked the first.

• Journal of Positioning, Navigation, and Timing
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• 제10권1호
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• pp.35-42
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• 2021

The position accuracy of the stand-alone Regional Navigation Satellite System (RNSS) users is more than tens of meters because of various error sources in satellite navigation signals. This paper focuses on wide-area differential (WAD) positioning technique, which is already applied in Global Navigation Satellite System (GNSS), in order to improve the position accuracy of RNSS users. According to the simulation results in the very narrow ground network in regional area, the horizontal position error of stand-alone RNSS is about RMS 11.6 m, and that of RNSS with WAD technique, named the WAD-RNSS, is about RMS 2.5 m. The accuracy performance has improved by about 78%.

• 한국항공우주학회지
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• 제45권4호
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• pp.310-317
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• 2017

오늘날 다양한 나라에서 위성항법시스템을 운용, 개발하고 있다. 또한 GNSS의 성능향상을 위해 정지궤도위성을 이용하는 SBAS가 운용 중에 있다. 가장 대표적으로 사용되는 SBAS는 미국에서 개발한 GPS의 WAAS이다. SBAS에서는 사용자에게 정확성, 가용성, 연속성, 무결성을 보장하기 위해 다양한 알고리즘이 사용되고 있다. 이 중 위성에 대한 무결성을 보장하기 위한 알고리즘이 있다. 이 알고리즘은 위성오차를 추정하고 보정정보를 생성하여 사용자에게 제공한다. 여기서 위성궤도오차를 3차원으로 추정하게 된다. 이렇게 위성궤도오차를 3차원으로 추정하기 위해서는 기준국 배치가 중요하게 된다. 기준국의 배치가 넓을수록 시선각 벡터가 넓게 분포되어 추정 정확도가 향상될 수 있다. 여기서 대표적 SBAS 운영국인 미국과 한국의 지역적 특성으로 인한 분석을 수행하고자 한다. 한국은 미국에 비해 매우 협소한 지리적 특성을 가지고 있다. 따라서 3차원 위성궤도오차 추정 기법을 그대로 사용하기 어렵다. 본 논문에서는 협역지역에서 위성궤도오차를 3차원으로 추정하는 것이 아닌 스칼라로 값으로 사용하는 방식을 제안한다. 제안하는 기법은 기준국(Reference)과 위성간의 시선각 (LOS, Line-Of-Sight) 벡터에 궤도오차를 투영한 스칼라 값을 이용하는 것이다. 이 방식을 이용하여 정상상태, 고장상태의 한국과 미국지역에서 기저선 거리에 따른 오차 변화를 확인하도록 한다. 이 오차변화 차이를 비교하여 제안하는 기법의 사용 가능성을 제시한다.

• 국제초고층학회논문집
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• 제10권3호
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• pp.203-210
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• 2021

With the development of urbanization, the increasing of buildings density in urban core areas result in the complexity of construction environment. High-rise landmark building is always preferred in the construction of urban core areas. Super high-rise buildings construction are facing construction management difficulties due to the complex working conditions and enormous building system, especially with the complex surrounding environment of the urban core area, the construction management of super high-rise buildings in the area requires higher, refined and detailed standard. Based on a super high-rise project in a core area of Shanghai which has 370 m building height and 772,643 m² building area, with complex surrounding environment, narrow construction site and many super-high-altitude crossing works. With the application of BIM technology, the Internet of Things, the LAN communication and other various intelligent mechanical equipment, information management systems, the efficiency and refinement of construction management are improved, ensuring the smooth implementation of the project while effectively controlling the impact on the surrounding environment.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.413-422
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• 1996

" Row -Zone Tillage" systems apply tillage procedures only to narrow strips of land where the next crop rows will be planted. The tilled zones are no more than 25% of the field area. Row-zone tillage procedures of crop production are conservative, where in the soil remains partially covered with protective residues while crops are planted , fertilized , grown , and harvested in the row-zones. Specially adapted implements are being developed for these operations. There is potential for minimizing farm machinery inventories. Limited crop response data are available from Canada and the USA.d the USA.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.66-70
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• 1998

The Chirisan earthquake occurred on July 4, 1936 was the largest earthquake known to have occurred in Southern Korean in the twentieth century. After, the magnitude of the earthquake was estimated to be ML = 5.0. It was recorded at eleven seismological stations and tremors were felt throughout the Southen Peninsula. However, damages were restricted in relatively narrow area including the SSangysa Temple and nearby town Sukmoon. Fairy detailed report(Hayata, 1940) was published and some reserches based on the report have been performed. The present study briefly introduces damages and researches corresponding the earthquake. Intensity attenuation and peak ground acceleration are also evaluated.