• 한국가구학회지
• /
• 제22권3호
• /
• pp.219-229
• /
• 2011

Sick building syndrome symptoms that are experienced by building occupants may be caused by toxic substances such as formaldehyde and VOCs, which are known to be emitted from building materials and wood composite products such as wood-based panel, furniture, engineered flooring and construction adhesive. In Korea, the use of wood composite products for indoor environments has increased over the last decade. Recently, wood composite products have been installed in approximately 95% of newly constructed residential buildings. The use of these products has resulted in problems related to human health, and consequently a realization about the importance of indoor air quality. In addition, consumer demand is increasing for natural materials because conventional building materials and wood composite products are made by adding urea-formaldehyde resin or they contain formaldehyde-based resin. More recently, many efforts have been made to reduce formaldehyde emission from building materials that laid in the indoor environment. Especially, if conventional formaldehyde-based adhesives are replaced with green adhesives for residential spaces, it is possible to reduce most of the emission amounts of formaldehyde in indoor environments. In line with this expectation, many researches are being conducted using natural materials such as tannin and cashew nut shell liquid (CNSL). This study discussed the affects and possibilities of green adhesives to reduce formaldehyde emission in indoor environments.

• 감성과학
• /
• 제16권3호
• /
• pp.311-318
• /
• 2013

본 연구는 인간의 생리적 지표 중 하나인 안면 피부온도를 활용하여 PMV 지표 값에 기반하여 조성된 쾌적/불쾌 실내 환경을 적절하게 구분할 수 있는지 그 타당성을 살펴보고자 하였다. 이를 위해 쾌적 실내 환경에 해당되는 PMV 지표 값을 기준으로 물리적 환경을 쾌적 실내 환경과 불쾌한 실내 환경으로 각각 구분하고, 구분된 환경내에서 재실자의 안면 피부온도를 측정하였다. 그 결과, PMV 지표 값으로 구분된 쾌적 실내 환경과 불쾌한 실내 환경에서의 재실자의 안면 피부온도가 서로 차이를 보이는 것으로 나타났다. 이는 안면 피부온도가 PMV 지표에 기반한 쾌적한 실내 환경 조성에 있어 활용될 수 있음을 시사한다. 그러나 쾌적한 실내 환경에 비해 불쾌한 실내 환경에서 안면 피부온도가 낮게 나타나는 결과를 통해 오히려 PMV 지표 값에 기반을 두고 조성되는 쾌적/불쾌환경이 타당하지 않을 수 있음도 시사한다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.1738-1741
• /
• 1997

This paper addresses the issue fo target classification and localization with a SONAR for mobiler robot indoor navigation. In particular, multiple refetions of SONAR sound are used actively and interntionally. As for the SONAR sensor, the multiple reflection has been generally considered as one of the noisy phenomena, which is inevitable in the indoor environments. However, these multiple reflections can be a clue for classifying and localizing targets in the indoor environment if those can be controlled and used well. This paper develops a new SONAR sensor module with a reflection plane which can actively create the multiple refection. This paper also intends to suggest a new target classification emthod which uses the multiple refectiions. We approximate the world as being two dimensional and assume that the targets consisting of the indoor environment are pland, corner, and edge. Multiple reflection paths of an acoustic bean by a SONAR are analyzed, by simulations and the patterns of the TOPs (Time Of Flight) and angles of multiple reflections from each target are also analyzed. In addition, a new algorithm for target classification and localization is proposed.

• 한국산업융합학회 논문집
• /
• 제23권2_2호
• /
• pp.255-261
• /
• 2020

We consider the problem of autonomously flying a quadcopter in indoor environments. Navigation in indoor settings poses two major issues. First, real time recognition of the marker captured by the camera. Second, The combination of the distributed images is used to determine the position and orientation of the quadcopter in an indoor environment. We autonomously fly a miniature RC quadcopter in small known environments using an on-board camera as the only sensor. We use an algorithm that combines data-driven image classification with image-combine techniques on the images captured by the camera to achieve real 3D localization and navigation.

• 한국통신학회논문지
• /
• 제36권2C호
• /
• pp.119-125
• /
• 2011

본 논문에서는 경로감쇠에 기반한 실내 음향측위 시스템에 활용할 수 있는 실내 음향신호의 경로 감쇠 특성을 분석한다. 실내 음향시스템은 주로 25 평방미터 이내의 협소한 공간에서 적용되기 때문에 기존에 정의된 넓은 공간에서의 모형만으로는 경로감쇠에 기반한 실내음향측위 시스템을 설계할 수 없다. 따라서 본 논문에서는 자유음장 모형과 더불어 실내공간의 온도와 습도, 그리고 대기의 주요구성성분의 홉음영향을 고려한 실내 음향신호 경로 감쇠 모형을 보이고, 무향실에서 실제 실험을 통해 모형의 적절성을 평가한다. 실험을 위해서 1kHz-20kHz의 단일 주파수를 갖는 감쇠정현파를 사용한다. 그리고 실험 음원으로 두개 이상의 단일 주파수를 갖는 감쇠정현파를 함게 사용할 대의 경로감쇠를 보이고, 이를 분석한다.

• 교육시설
• /
• 제16권6호
• /
• pp.29-41
• /
• 2009

The purpose of the study was to determine the way to improve the school environments especially focused on the elementary school through design gaming with children. Main purpose of the study was to establish the method to find how children experience school environments and the way to find their needs, feelings, and desires of the school facilities. The methods which have been used are design gaming consisted of picture card game, drawing favorable and unfavorable places, and making the wish list. 46 children in Seoul area participated in the study. The main physical environments which have been focused in the study are as follows; the type of classroom, atmosphere of library, indoor and outdoor leisure activity space, indoor and outdoor play area, and the pedestrian way from home to school and from school towards home. Quantitative and qualitative analysis were used to attempt to develop children's preference of each place and their wish about school environments. The results have been summarized based on the general preferences and differences of favorite and unfavorite places. The differences between grades and gender have also been discussed focused on the picture game and drawings of favorite and unfavorite places.

• 한국산업정보학회논문지
• /
• 제17권2호
• /
• pp.1-9
• /
• 2012

오늘날 무선센서노드는 환경모니터링과 같은 다양한 응용분야에서 많이 사용된다. 본 논문에서는 실내환경에서 전파를 방해하는 장애물(콘크리트 내벽, 철문)과 2.4GHz의 무선랜(IEEE 802.11b/g)이 있는 환경에서 센서노드의 RSSI(Received Signal Strength Indication)와 PER(Packet Error Rate)을 측정하였다. 또한 다양한 실외 환경에서 센서노드의 RSSI와 PER을 측정하였다. 본 논문을 통해 분석되어진 데이터를 바탕으로 실내외 환경에서 데이터의 손실을 최소화할 수 있는 안정적인 무선센서네트워크의 구축에 필요한 가이드라인을 제시한다.

• 대한인간공학회지
• /
• 제20권2호
• /
• pp.29-46
• /
• 2001

This study is about the modeling of comfort feeling structure in indoor environments. To represent the degree of practical comfort feeling level in an environment, we measured elements of human sense and resultant elements of comfort feeling such as coziness, refreshment, and freshness with physical values(temperature, illumination, noise. etc.). The relationships of elements of human sense and elements of comfort feeling were formulated as a fuzzy model. And a hybrid-neural network with three layers were designed where obtained from fuzzy membership function values of the elements of human sense were used as inputs, and given as fuzzy membership function values of resultant elements of comfort feeling were used as outputs. Both kinds of fuzzy membership function values were obtained from physical values. The network was trained by measured data set. The proposed hybrid-neural network were tested and proposed a more realistic model of comfort feeling structure in indoor environments.

• 전기전자학회논문지
• /
• 제20권1호
• /
• pp.1-8
• /
• 2016

In this paper, we propose an effective time-of-arrival (TOA)-based localization method with adaptive bias computation in indoor environments. The goal of the localization is to estimate an accurate target's location in wireless localization system. However, in indoor environments, non-line-of-sight (NLOS) errors block the signal propagation between target device and base station. The NLOS errors have significant effects on ranging between two devices for wireless localization. In TOA-based localization, finding the target's location inside the overlapped area in the TOA-circles is difficult. We present an effective localization method using compensated distance with adaptive bias computation. The proposed method is possible for the target's location to estimate an accurate location in the overlapped area using the measured distances with subtracted adaptive bias. Through localization experiments in indoor environments, estimation error is reduced comparing to the conventional localization methods.

• 로봇학회논문지
• /
• 제18권2호
• /
• pp.135-142
• /
• 2023

Light detection and ranging (LiDAR) sensors have been most widely used in terrestrial robotic applications because they can provide dense and precise measurements of the surrounding environments. However, the reliability of LiDAR measurements can considerably vary due to the different reflectivities of laser beams to the reflecting surface materials. This study presents a robust LiDAR-based mapping method for the varying laser reflectivities in indoor environments using the framework of simultaneous localization and mapping (SLAM). The proposed method can minimize the performance degradations in the SLAM accuracy by checking and discarding potentially unreliable LiDAR measurements in the SLAM front-end process. The gaps in point-cloud maps created by the proposed approach are filled by a Gaussian process regression method. Experimental results with a mobile robot platform in an indoor environment are presented to validate the effectiveness of the proposed methodology.