• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 학술발표대회 논문집
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• pp.1-6
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• 1996

A seeder monitoring system was developed to remove the uneasiness of mis-sowing that drop operations efficiency at sowing-work and to make reliable and stable work. The objectives of this study are to investigate that the system developed is applicable to sowing soybean seeds and scattering fertilizer and to evaluate performance of the system developed through the indoor test and the indoor test and the field test before it is propelled to put the system developed to practical use.

• 한국대기환경학회지
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• 제25권1호
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• pp.38-45
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• 2009

Since the seventies and the oil crisis, energy-saving measures have led to a reduction in the ventilation of room. The use of synthetic materials which emit various chemical substances had led to an increase in the concentration of indoor pollutants. "Sick building syndrome (SBS)" and "Sick house syndrome (SHS)" are worldwide problems. Also, the number of complaints about indoor air pollution caused by VOCs (Volatile organic compound) and HCHO (Formaldehyde) has increased. It is important that evaluating and understanding emission of indoor air pollutant from building materials. The object of this study was to evaluate emission test method for flooring such as wood based flooring, carpet tile, rubber tile, PVC sheet and tile, and to determine emission of TVOC and form-aldehyde. The quantity of TVOC and carbonyl compounds emission were sampled and measured by Tenax TA and gas chromatography/mass spectrometry (GC/MSD), 2,4-DNPH cartrige with ozone scrubber and high performance liquid from flooring. The TVOC concentration emitted from carpet tile was ($7.419\;mg/m^2 h$) the highest among 5 groups of test materials. In wood based flooring and PVC tile, the emitted concentration of toluene was high. And the dodecane emission was highest in carpet. The concentration of TVOC decreased by an increase in emission test period. After 7 days, the concentration of TVOC from floorings were about 50% below of the concentration at the first day. TVOC emission from wood based flooring, carpet tile, rubber tile, PVC sheet and tile were decreased in 28 days and remained steady after about 15 days. The concentration of formaldehyde emission from floorings showed extremely low.

• 분석과학
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• 제22권5호
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• pp.369-375
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• 2009

저농도 섬유상 분진 표준시료를 제조하여 균질도와 정확성을 조사하고, 모의 숙련도 시험을 통해 최적의 숙련도 시험 방안을 평가하였다. 분석 결과 표준시료 농도와 석면밀도의 상관성이 0.9863~0.9968으로 매우 높게 나타났고, 표준시료를 이용한 모의 숙련도 시험을 통해서, 국내에서의 숙련도 시험 결과 평가 기준은 표준시료 분석결과의 Z값이 ${\mid}Z{\mid}{\leq}2$를 만족하는 것이 타당한 것으로 나타났다.

• 로봇학회논문지
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• 제6권1호
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• pp.58-68
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• 2011

This paper proposes a technique of indoor localization for mobile robot by so called indoor GPS and EKF. Basically the concept of indoor GPS is similar outdoor GPS, and the indoor GPS gets distances between Anchors and Tag by a ranging method of CSS and then estimates the coordinate by distances and known Anchor positions. After we performed performance test of indoor GPS system in ideal and multipath environment, we configured that the indoor GPS has internal error factors and external error factors. This paper handled a multipath problem belonging to external error factors. At first various direct physical method are introduced to fix the multipath problems, and as expected we got errors corrected considerably. And then the method of selective anchors for indoor GPS is applied. With these two level improvement of indoor GPS performance, EKF(Extended Kalman Filter) is applied to mobile robot in indoor environment. The usefulness of the proposed methods are shown by a series of experiments in a environment giving contaminated data by multipath.

• 한국항공우주학회지
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• 제37권12호
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• pp.1209-1216
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• 2009

본 논문에서는 실내 공간에 설치된 복수의 카메라로부터 획득한 영상정보를 소형무인기의 자세 추정 및 제어에 이용하는 시스템에 대한 연구를 기술하였다. 제안된 시스템은 실외 비행시험의 제한을 극복하고 효율적인 비행시험 환경을 구축하기 위한 것으로 무인기의 위치 및 자세를 측정하기 위해 별도의 센서를 탑재할 필요가 없어 저가의 장비로 테스트베드를 구성할 수 있다는 장점을 갖는다. 시스템 구현을 위해 요구되는 카메라 보정, 마커 검출, 자세 추정 기법을 소개하였으며 테스트베드를 이용한 실험 결과를 통해 제안된 방법의 타당성 및 성능을 보였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.123-124
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• 2023

Despite the acuuracy, stability, and economic feasibility of geomagnetic field-based indoor positioning, its applicability in construction sites needs to be thoroughly discussed due to the issue of distortion of geomagnetic fields around ferromagnetic objects such as rebars. In this study, the possibility of applying the geomagnetic field-based indoor positioning in construction sites was reviewed through the Student's t-test after measuring the changes in geomagnetic field values depending on the presence or absence of rebars. The statistical analysis revealed that there is a high probability (over 80%) of significant changes in geomagnetic field values when measuring points are located within 60cm from the rebars. On the other hand, the probability of minimal changes in geomagnetic field values is over 90% when measuring points are located more than 60cm from the rebars. This suggests the application of geomagnetic-based indoor positioning in construction sites would be possible if the issue of distortion in geomagnetic field values near rebars within 60cm is resolved.

• 한국주거학회논문집
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• 제17권5호
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• pp.9-16
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• 2006

The researches on the environmental friendly buildings have carried out on the materials, environmental property, technical elements and etc., and various buildings with these green materials have built and under construction nowadays and became a new trend of the green building. And recently, new building technique which builds the wall with the soil and wood and very easy to construct (called M Earthen House) was introduced as the green building and rapidly propagated. But the research on the indoor climatic characteristics, the ability to control the environmental comfort and the influence to the human beings of these buildings are not sufficiently identified yet. In this paper, the indoor environmental characteristics and the temperature controlling ability of these buildings in summer season were measured and analysed by the Portable Indoor Air Quality Monitor(BABUC/A, LSI) measuring equipments, ana the subjective test on the thermal environment of the subjects were carried out to evaluate the thermal comfort. The results can be summarized as follows; 1) Compared to the outdoor dry bulb temp.($15.4{\sim}28.7^{\circ}C$), the indoor temp. was $19.5{\sim}26.8^{\circ}C$. It showed the temperature controlling ability of the M earthen house was outstanding. And the indoor relative humidity, compared to the outdoor($45.4{\sim}100%$), was $58.1{\sim}76.4%$, it showed the humidity controlling ability of the M earthen house was also outstanding. 2) The thermal environment was evaluated as 'comfort'(neutral-slightly warm) and the humidity was also evaluated as 'comfort'(neutral-slightly humid). So, the results of the physical and subjective evaluation on the indoor thermal comfort in summer season were 'neutral' and 'comfort' coincidently, it was confirmed that the controlling ability of the indoor temperature and humidity of the M earthen house was very excellent.

• Journal of Positioning, Navigation, and Timing
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• 제10권2호
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• pp.121-130
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• 2021

In this paper, we propose a method to improve the positioning accuracy of TOA based indoor positioning system in NLOS environments. TOA based indoor positioning systems have been studied mostly considering LOS environments. However, it is almost impossible to maintain the LOS environments due to obstacles such as people, furniture, walls, and so on. The proposed method in this study compensates the range error caused by the NLOS environments. We confirmed that positioning accuracy of a proposed method is improved than conventional algorithms through simulation and field test.

• 한국멀티미디어학회논문지
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• 제12권1호
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• pp.97-106
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• 2009

무선 근거리 통신망 환경의 측위 전략은 정확도는 떨어지지만 측위를 위한 특수 장비가 필요 없다는 점에서 매력이 있다. 본 논문은 무선 근거리 통신망 환경에서 옥내 이동 물체의 제적을 의사 결정 트리기법을 이용한 측위 방법으로 측정하고, 측정치가 실제 궤적과 다르지 않음을 통계적으로 검정함으로써 이렇게 얻은 궤적을 실제 응용 시스템 개발에 사용하여도 좋다는 이론적 근거를 제공한다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.435-440
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• 2009

For the effective control of a $CO_2$ air-conditioning system, the system high-side pressure algorithm, the indoor temperature algorithm, and the outdoor fan algorithm were developed. The system high-side pressure algorithm was composed of the setpoint algorithm, the reset algorithm, and the electronic expansion valve control algorithm. The indoor temperature algorithm was composed of the compressor control algorithm and the indoor fan control algorithm. These algorithms were tested by using mathematical models developed from the previous study. Results from the setpoint step change test and the disturbance test showed good control performances. Therefore, algorithms developed in this study may practically used for the control of a $CO_2$ air-conditioning system.