• 한국IT서비스학회지
• /
• 제9권3호
• /
• pp.145-161
• /
• 2010

Recently, identifying user locations is becoming important as the society evolves into an ubiquitous society with the innovation of information technology. Particularly, many researches on identifying user locations are headed in direction to identify locations of users in the indoors, because a GPS that is widely used to identify the locations of users in the outdoors is inapplicable in the indoors. However, those researches are mostly not useful to general indoor environment because they are performed in a specific environment with specialized or customized devices such as UWB, RFID. Therefore, in this paper we propose a effective method to identify user locations in general indoor environments with wireless local network access points. Our approach enables to identify user location efficiently by measuring signal power of access points around the user and using the FRIIS formula which is used to calculate the distance among the things.

• 한국지능정보시스템학회:학술대회논문집
• /
• 한국지능정보시스템학회 2005년도 공동추계학술대회
• /
• pp.147-156
• /
• 2005

In developing the ubiquitous computing technology based services (ubiquitous services), evaluating how much value of those services is created or added is very crucial. The efforts to evaluate the ubiquitous services have been progressed in two perspectives - technical perspective and behavioral perspective. Despite its importance, however, the methodologies which integrate both perspectives have been still very rare. Hence, this paper aims perspectives have been still very rare. Hence, this paper aims to propose an integrated ubiquitous service valuation methodology based on the multi-layered approach including technical and behavioral perspectives. To do so, we conducted a case study with currently existing location based service (LBS) such as navigation systems by conducting focus group interview (FGI) and field survey.

• 한국군사과학기술학회지
• /
• 제10권3호
• /
• pp.25-33
• /
• 2007

In this paper, I propose a method which can enhance the visual quality of IRST images based on a loaded location in ship and an AOS. The IRST adjusts an AOS to detect targets with various altitudes because of its narrow vertical field of view and offers various functions to enhance images with its low contrast. In the proposed method, images are divided into two regions of sea and sky on the basis of the horizon after establishing relation between an AOS and a horizon location within an image. As a result, image enhancement of the proposed method is performed adaptively according to the divided region while that of conventional method is performed for entire image without the region division. Simulation results show that the proposed method represents higher visibility compared with conventional one.

• Journal of Information Processing Systems
• /
• 제16권3호
• /
• pp.639-647
• /
• 2020

In the vibration target localization algorithms based on time difference of arrival (TDOA), Fang algorithm is often used in practice because of its simple calculation. However, when the delay estimation error is large, the localization equation of Fang algorithm has no solution. In order to solve this problem, one dimensional search location algorithm based on TDOA is proposed in this paper. The concept of search is introduced in the algorithm. The distance d1 between any single sensor and the vibration target is considered as a search variable. The vibration target location is searched by changing the value of d1 in the two-dimensional plane. The experiment results show that the proposed algorithm is superior to traditional methods in localization accuracy.

• 산업경영시스템학회지
• /
• 제22권49호
• /
• pp.99-113
• /
• 1999

This paper describes a study which was undertaken in Ulsan City. It attempted to develop stepwise procedures that would aid Ulsan City in making decision of primary importance: what is the optimal site location for establishing a new Industrial Technology Research Park for public development\ulcorner The presented modeling procedures are an adaption of a number of exiting methods for the evaluation of industrial site potential. The procedures to determine the best site location can be divided into three phases : (i)defining the information necessary to compare potential sites, (ii) collecting the information for each site and (iii)evaluation potential sites utilizing the location model.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2019년도 춘계학술대회
• /
• pp.462-463
• /
• 2019

본 논문에서 연구하는 방안은 석탄 화력발전소의 옥내 저탄장 석탄의 자연발화를 예방하기 위한 방법으로, 석탄의 자연발화를 사전에 감지하여 발화 장소의 위치를 알람서비스를 할 수 있게 하기 위한 위치 확인 방안으로 사물인터넷기술(IoT)과 센서기술을 접목하여 석탄의 저장소의 온도를 24시간 모니터링을 통해 전체 저장된 석탄의 온도변화를 감지하는 것이다.

• ETRI Journal
• /
• 제45권6호
• /
• pp.939-951
• /
• 2023

It is critical to estimate the location using only Long-Term Evolution (LTE) and Wi-Fi information gathered by the user's smartphone and deployable for emergency rescue, regardless of whether the Global Positioning System is received. In this research, we used a vehicle to gather LTE and Wi-Fi wireless signals over a large area for an extended period of time. After that, we used the learning technique to create a positioning database that included both collection and noncollection points. We presented a two-step positioning algorithm that utilizes coarse localization to discover a rough location in a wide area rapidly and fine localization to estimate a particular location based on the coarse position. We confirmed our technology utilizing different sorts of devices in four regional types that are generally encountered: dense urban, urban, suburban, and rural. Results presented that our algorithm can satisfactorily achieve the target accuracy necessary in emergency rescue circumstances.

• 한국IT서비스학회지
• /
• 제13권4호
• /
• pp.205-230
• /
• 2014

In recent years, the social network service (SNS) and the location-based social network service (LBSNS) industry is expanding and the competition within the field is increasing much more. Since 2010, the full-scaled studies of SNS and LBSNS have begun. With the growth of SNS and LBSNS markets, SoLoMo (Social-Local-Mobile) is also becoming the trend for applications in different fields. However, despite the importance of SoLoMo, there have been little studies on the characteristics of SoLoMo applications. The purpose of this research is to investigate the effect of characteristics and perceived privacy risk of mobile location-based SNS on intention to use SoLoMo applications. For the purpose, we proposed a SoLoMo service acceptance model with TAM (Technology Acceptance Model) and the characteristics of SoLoMo applications. The characteristics consist of three factors, i.e. SNS, location, and mobile-related factors. This study also considered a gamification and a perceived privacy risk factor influencing on SoLoMo service usage in our proposed research model. The results of our empirical analysis using partial least squares (PLS) method show that the characteristics of SoLoMo applications including SNS, location, and mobile-related features, gamification, and perceived privacy risk have partially an effect on intention to use SoLoMo applications. Based on these results, SoLoMo-related companies will be able to increase the usage of SoLoMo services by differentiating their own strategies with these factors influencing on SoLoMo services.

• 디지털콘텐츠학회 논문지
• /
• 제16권2호
• /
• pp.179-187
• /
• 2015

스마트폰의 보급 확산으로 다양한 콘텐츠가 등장하고 있다. 이러한 콘텐츠 중에서 위치 기반 서비스를 이용한 증강현실 응용프로그램의 필요성이 널리 대두되고 있다. 본 논문에서는 안드로이드 스마트폰을 이용한 위치정보기반 AR 시스템에서 발생하는 정합 오차를 컴퓨터 비전 기술을 이용하여 효과적으로 줄이는 방법을 제안한다. 위치정보 오차 누적 때문에 객체가 정확하게 정합되지 않는 부정합 현상 최소화를 위해 연산 속도는 유지하면서 연산량을 줄여 성능을 향상한 방법인 SURF(Speeded Up Robust Features)를 사용해 초기 특징점을 검출하고 검출된 특징점을 추적하여 모바일 환경에 적용한다. 위치정보 검색을 위해 GPS 정보를 사용하고 자세추정 및 방향 정보를 위해 자이로 센서, G-센서 등을 이용한다. 하지만 위치정보의 누적된 오차는 객체가 고정되지 않는 부정합 현상을 유발한다. 또한, 증강현실 기술은 구현하면서 많은 연산량이 필요하므로 모바일 환경에서 구현하는데 어려움이 발생한다. 제안된 방법은 모바일 환경에서 성능 저하를 최소화하고 비교적 간단하게 구현할 수 있어 기존 시스템 및 다양한 모바일 환경에서 유용하게 이용될 수 있다.

• Journal of Ship and Ocean Technology
• /
• 제12권3호
• /
• pp.26-35
• /
• 2008

Recognition of real time locations of crews for a naval ship is important, not only for the operation efficiency but also for the safety of onboard crews in the ship. More than 100 crews are dwelling in a modem naval ship and they are involved in various duties. Moreover many visitors come in and out frequently while the ship is moored in a harbor. It sometimes requires considerable time and efforts to find a person for urgent mission. It would enhance the operational efficiency if locations of onboard crews are recognized and monitored in real time. An active type RFID tag, which has a specific ID number, is distributed to each crew member, which should be carried during his stay in the ship. A number of fixed type RFID readers are to be located at the major passages of the ship, which are connected to the main computer via Local Area Network. The location of a crew would be identified by the ID number of his RFID tag and the location of the RFID reader which detected the RFID tag. A middleware is needed to process the collected data in the main computer. The data is fed to application softwares, which actually display locations of the concerned crews. The software is coded using GUI (Graphic User Interface) for better user friendliness, which has the function of storing the location history of a crew, and sending warning messages to appropriate persons, if unallowable behavior is detected. An auxiliary naval ship is selected for an experimental application study of the proposed system. It turns out that the required budget and time for the realization of the system is within the allowable limits. But complementary measures to protect the privacy of onboard crews should be considered and adopted, before the application of the system is realized.