• Environmental Analysis Health and Toxicology
• /
• 제28권
• /
• pp.5.1-5.7
• /
• 2013

Objectives Despite increasing availability of global positioning system (GPS), no research has been conducted to analyze GPS data for exposure opportunities associated with time at indoor and outdoor microenvironments. We developed location-based and time-weighted spatial measures that incorporate indoor and outdoor time-location data collected by GPS. Methods Time-location data were drawn from 38 female subjects in California who wore a GPS device for seven days. Ambient standard deviational ellipse was determined based on outdoor locations and time duration, while indoor time weighted standard deviational ellipse (SDE) was developed to incorporate indoor and outdoor times and locations data into the ellipse measure. Results Our findings indicated that there was considerable difference in the sizes of exposure potential measures when indoor time was taken into consideration, and that they were associated with day type (weekday/weekend) and employment status. Conclusions This study provides evidence that time-location weighted measure may provide better accuracy in assessing exposure opportunities at different microenvironments. The use of GPS likely improves the geographical details and accuracy of time-location data, and further development of such location-time weighted spatial measure is encouraged.

• 한국IT서비스학회지
• /
• 제10권4호
• /
• pp.243-258
• /
• 2011

With increasing interest in ubiquitous computing technology, an infrastructure for the short-distance wireless communication has been extended socially, bringing spotlight to the security system using the image or location. In case of existing security system, there have been issues such as the occurrences of blind spots, difficulty in recognizing multiple objects and storing of the unspecified objects. In order to solve this issue, zone-based location-estimation search system for the image have been suggested as an alternative based on the real-time location determination technology combined with image. This paper intends to suggest the search service for the image zone-based location-estimation. For this, it proposed the location determination algorism using IEEE 802.15.4/ZigBee's RSSI and for real-time image service, the RTP/RTCP protocol was applied. In order to combine the location and image, at the event of the entry of the specified target, the record of the time for image and the time of occurrence of the event on a global time standard, it has devised a time stamp, applying XML based meta data formation method based on the media's feature data based in connection with the location based data for the events of the object. Using the proposed meta data, the service mode which can search for the image from the point in time when the entry of the specified target was proposed.

• 한국공간정보시스템학회 논문지
• /
• 제7권2호
• /
• pp.47-56
• /
• 2005

최근 이동 컴퓨팅 기술과 무선 측위 기술이 급속도로 발전하고 무선 인터넷이 보편화됨에 따라 이동체의 위치 정보를 활용하는 위치 기반 서비스(LBS: Location Based Service)가 다양한 분야에서 제공되고 있다. 위치 기반 서비스를 제공하기 위해서는 이동체의 위치 정보를 주기적으로 저장하는 위치 데이타 서버가 필요하다. 기존에는 이동체의 위치 데이타를 저장하기 위해서 GIS 서버를 사용해 왔다. 하지만 GIS 서버는 정적 데이타를 기반으로 설계되었기 때문에 이동체의 위치 데이타를 저장하는데 적합하지 않다. 따라서, 본 논문에서는 이동체의 위치 데이타를 관리하기 위해 제안된 클러스터 기반 분산 컴퓨팅 구조를 갖는 GALIS(Gracefully Aging Location Information System) 아키텍처의 서브 시스템인 SLDS(Short-term Location Data Subsystem)를 확장하여 실시간 위치 기반 서비스를 위한 확장 SLDS를 설계 및 구현하였다. 확장 SLDS는 TMO(Time-triggered Message-triggered Object) 프로그래밍 기법을 이용하여 위치 데이타 처리의 실시간성을 보장하며, 이동체 데이타를 다수의 노드에 적절히 분산시킴으로써 대용량 위치 데이타를 효율적으로 관리할 수 있다. 그리고, 메인메모리에서 위치 데이타를 관리하기 때문에 검색 및 갱신 오버헤드가 적다. 또한, 실험을 통하여 확장 SLDS는 기존에 제시된 SLDS 보다 더 효율적인 저장과 부하 분산을 수행한다는 것을 확인하였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
• /
• pp.10-11
• /
• 2006

The fault location is obtained from the distance relay that detects the fault of the transmission line. In this time, transmission line crews track down the fault location and the reasons. However, because of having error at the fault location of the distance relay, there is a discordance between real and obtained fault location. As this reason, the inspection time for finding fault location can be longer. In this paper, we proposed the statistical (regression) analysis method based on each type of relay's the historical fault location data and the real fault distance data to improve the problems. With finding the regression equation based on the regression analysis, and putting the relay fault location into that equation, the real fault distance is calculated. As a result of the Prediction fault location, the inspection time of transmission line can be reduced.

• 한국환경보건학회지
• /
• 제42권5호
• /
• pp.314-323
• /
• 2016

Objectives: Time location data are critical for accurately estimating personal exposures. This review papers summarized various measurement methods of time location pattern for air pollution exposure assessment. Methods: Forty manuscripts (papers, books and reports) were reviewed to comprehensively describe time location measurement methods. Results: This review included traditional methods such as time activity diary, questionnaire, observation, focus group and newly developed technical methods including global positioning system, web, radio frequency identification and ultrasound detection. Some research applied a combination of methods. Conclusion: Although various methods have been used to collect time location data, further development of accurate measurement methods for time location data is needed.

• 한국컴퓨터정보학회논문지
• /
• 제23권11호
• /
• pp.95-101
• /
• 2018

In this paper, we propose an efficient friendly forces location data sharing algorithm in a troops using a low bandwidth radio. The future battlefield is a 'Network Centric Warfare' with a concept of identifying the position and power of the enemy and friendly forces and leading the battlefield to victory through proper links at the time of our need. One of the basic elements in the 'Network Centric Warfare' is to share friendly forces location data. The bandwidth and transmission rates of radio used in battalion are low. Nevertheless, we should share our locations data almost in real time for effective fighting in a war situation. This paper describes the efficient method of friendly forces location data sharing based on low bandwidth radio. In particular, the concept of 'network-centered warfare' is reflected in the troop below the battalion to present an integrated and efficient way to shared location data of friendly forces.

• International Journal of Contents
• /
• 제17권3호
• /
• pp.74-83
• /
• 2021

A location-aware algorithm is proposed in this study to optimize the system performance of distributed systems for processing big data with low data reliability and application performance. Compared with previous algorithms, the location-aware data block placement algorithm uses data block placement and node data recovery strategies to improve data application performance and reliability. Simulation and actual cluster tests showed that the location-aware placement algorithm proposed in this study could greatly improve data reliability and shorten the application processing time of I/O interfaces in real-time.

• 한국멀티미디어학회논문지
• /
• 제9권4호
• /
• pp.388-400
• /
• 2006

LBS의 주요 기술 구성요소에는 무선측위기술 또는 위치결정기술, LBS 핵심기반 기술 및 LBS 응용기반 기술 등이 있다. 이 논문에서는 LBS의 주요기술 구성요소 중 핵심기반기술인 위치 데이터 관리 시스템을 설계한다. 제안 시스템은 LBS 응용인터페이스, 응용서비스 질의처리기, 이동객체 위치추정기, 위치정보 관리기, 실시간 데이터 수신기, 위치정보 데이터베이스로 구성된다. 데이터베이스 관리 기술을 활용하여 이동객체의 위치변화 정보를 효율적으로 관리하고 이와 관련된 유용한 정보를 LBS 사용자에게 제공하며, 기존의 상용 데이터베이스에서 처리할 수 없는 이동객체의 연속적인 위치정보를 처리하는 연산 및 위치추정 기능을 지원한다. 실시간 환경에서 발생되는 위치정보의 결손을 보완하는 위치정보 트리거링을 토대로 기존의 위치 정보 관리 시스템이 갖는 문제점을 보완한다. 제안한 위치 데이터 관리 시스템의 응용을 위해 산불관리 응용서비스에 적용한 결과를 보인다.

• 국제학술발표논문집
• /
• The 6th International Conference on Construction Engineering and Project Management
• /
• pp.10-14
• /
• 2015

Unsafe behavior is one of the major causes of construction accidents. Managing the behavior of workers in real-time is difficult and requires huge manpower. In this paper, a new real-time locating framework is proposed to improve safety management by collecting and analyzing data describing the behavior of workers to identify habits that may lead to accidents. The aim of the study is to identify working habits of workers based on their location history. Location data is used to compare with that of other workers and equipment. The results indicate that the reuse of real-time location data can provide extra safety information for safety management and that the proposed system has the potential to prevent struck-by accidents and caught-in between accidents by predicting unwanted interaction between workers and equipment. This adds to current research aimed at automating construction safety to the point where the continuous monitoring, managing and protection of site workers on site is possible.

• International Journal of Contents
• /
• 제13권1호
• /
• pp.22-30
• /
• 2017

The diffusion of advanced mobile technology has introduced new types of personal information or 'location data'. These new data mean new opportunities for businesses, such as location-based services (LBS), but have resulted in new consumer anxieties regarding disclosure of personal information. This study examines the effects of the consumers' perceived control over "time-andplace" information in location-aware services on their perceived privacy risk. A total of 270 respondents participated in this study. Conditions of perceived privacy control were operationalized over time-and-place information, in a $2{\times}2$ factorial design. Results indicate that the perceived control over time-and-place personal information is a significant predictor of perceived risk, and control assurances over time-and-place information enhances the perception of control, thus alleviating the perceived risk. In addition, the effect is much more significant when time and place were combined.