• The KIPS Transactions:PartC
• /
• v.8C no.6
• /
• pp.639-639
• /
• 2001

In this paper we describe a distributed location management scheme to reduce the bottleneck problem of HLR in Large Personal Communication Networks (LPCNs). Using analytical modeling and numerical simulation, we show that replicating location information is both appropriate and efficient for small Personal Communication Network (PCN). Then, we extend the scheme in a hierarchical environment to reduce overhead traffic and scale to LPCNs. Through extensive numerical results, we show the superiority of our scheme compared to the current IS-41 standard scheme.

• The KIPS Transactions:PartC
• /
• v.8C no.6
• /
• pp.839-846
• /
• 2001

In this paper we describe a distributed location management scheme to reduce the bottleneck problem of HLR in Large Personal Communication Networks (LPCNs). Using analytical modeling and numerical simulation, we show that replicating location information is both appropriate and efficient for small Personal Communication Network (PCN). Then, we extend the scheme in a hierarchical environment to reduce overhead traffic and scale to LPCNs. Through extensive numerical results, we show the superiority of our scheme compared to the current IS-41 standard scheme.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.8
• /
• pp.1407-1414
• /
• 2016

In this study, we develop that Location Recommending System using personal emotion information based on Collaborative Filtering. Previous Location Recommending System recommended a place visited by the user of the rating or the pattern of location for the user place. These systems are not high user satisfaction because that dose not consider the user status or have not objectively the information. Using user's personal emotion information to recommend a high-affinity users who have visited the place felt similar emotions objectively can improve user satisfaction with the place. In this study, a user using a mobile application directly register the recognized emotion information using the current position and bio-signal, and using the registered information measuring the similarity of user with a similarity emotion, predicts a preference for the place it is recommended to emotional place. The system consists of a user interface, a database, a recommendation module.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.6
• /
• pp.181-186
• /
• 2017

Child crimes such as child abduction and lost children(MIA) have long been pointed out as social problems. However, there are few ways to solve these problems. According to MIA statistics, about 3,000 babies are lost each year. This paper presents a study on prevention of lost children ratio using mobile LBS in order to reduce the incidence of lost children ratio in dense space. First, we input the personal information of the child and the contact information of the parent. Second, we use the Google Maps API to get the location (parent's location, child's location) information. Third, the personal information of the child and the parent is indicated in the obtained location information. In future research, based on SNS, we will carry out research on sending child location information and parent location information via SMS. It is expected that the prevention system of lost child using LBS and SNS will make a great contribution to reduce the lost children ratio in the ubiquitous society.

• Proceedings of the KIEE Conference
• /
• 2006.10c
• /
• pp.163-165
• /
• 2006

The subway passengers are usually alert to the current location of the train in order not to miss the destination or transfer stations. The Global Positioning System (GPS), although expensive, can give an alarm if properly programmed, but cannot receive the satellite signals, underground. Therefore, a novel approach to context-aware location-based subway information system is motivated. The passengers, who are equipped with mobile devices such as laptop, PDA, and mobile phone as clients of the Personal Area Network (PAN), request the Bluetooth connection to the server which is installed in each car of the train. While the sorrel broadcasts the location-based information including the previous station, the current velocity of the train, the distance and time to the next station, the clients provide additional services based on the recognized context of the information, and what the passengers individually want. The services are spontaneous and autonomous rather than passive. The services include not only the information on the nearby stations, exit numbers, connection buses but also the location-based alarms which can be set specific to various personal requests, and sounded by the location of the train rather than time. Whereas the arrival time may not be accurate due to the delays of the train, the location can be accurately traced and broadcast by the server. Also, the clients do not need any expensive systems like GFS. Towards validating the proposed approach, we implemented a Bluetooth PAN including a PC server, two PDA clients and a laptop client. We modeled a train on the Incheon Subway Line #1 and a train on the Seoul-to-Incheon Line on the server, simulated the virtual trains together with the real clients. and verified that all the services were successfully provided.

• Journal of Information Processing Systems
• /
• v.1 no.1 s.1
• /
• pp.86-95
• /
• 2005

Location-based services or LBS refer to value-added service by processing information utilizing mobile user location. With the rapidly increasing wireless Internet subscribers and world LBS market, the various location based applications are introduced such as buddy finder, proximity and security services. As the killer application of the wireless Internet, the LBS have reconsidered technology about location determination technology, LBS middleware server for various application, and diverse contents processing technology. However, there are fears that this new wealth of personal location information will lead to new security risks, to the invasion of the privacy of people and organizations. This paper describes a novel security approach on open LBS service to validate certificate based on current LBS platform environment using XKMS (XML Key Management Specification) and SAML (Security Assertion Markup Language), XACML (extensible Access Control Markup Language) in XML security mechanism.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2021.11a
• /
• pp.895-898
• /
• 2021

DB로부터 위치 데이터를 추출해오면, location visiting measure를 통해 한 개인의 장소 방문 선호도를 측정한다. 이 과정에서 위치 데이터 클러스터링 및 개인의 이동성 파악을 위한 6가지 조치를 한다. 위치 데이터 분석 결과로 얻은 이동성 통계는 LBS(Location Based System)를 포함한 다양한 분야에 적용될 수 있다. 연구의 최종 목표는 새로운 위치 데이터의 수집에 따른 방문 선호도 변화를 적용할 수 있도록 하는 location visiting measure의 자동화 시스템을 구축하는 것이다.

• Proceedings of the IEEK Conference
• /
• 2002.07b
• /
• pp.1090-1093
• /
• 2002

Location management schemes dealing with location information of moving terminals play an important role in the personal communications systems (PCS). Since the location management involves heavy signaling traffics to update the location information, reducing the location update cost becomes a critical research issue. This paper proposes a location management scheme which reduces the location update cost by employing the hierarchical structure in PCS environment. The paper also develops analytical models to evaluate the performance of the proposed scheme. The results obtained from the performance evaluation shows that the proposed scheme outperforms the conventional schemes in terms of the location update rates. Also, the difference in the performance becomes larger as the size of the location area (LA) becomes smaller and as the residual time of the mobile user becomes smaller.

• Journal of KIISE
• /
• v.42 no.2
• /
• pp.190-202
• /
• 2015

Much research has been conducted on location-based intelligent personal assistants that can understand a user's intention by learning the user's route model and then inferring the user's destinations and routes using data of GPS and other sensors in a smartphone. The intelligence of the location-based personal assistant is contingent on the accuracy and efficiency of the real-time predictions of the user's intended destinations and routes by processing movement information based on uncertain sensor data. We propose a robust particle filter based on Dynamic Bayesian Network model to infer the user's routes. The proposed robust particle filter includes a particle generator to supplement the incorrect and incomplete sensor information, an efficient switching function and an weight function to reduce the computation complexity as well as a resampler to enhance the accuracy of the particles. The proposed method improves the accuracy and efficiency of determining a user's routes and destinations.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06a
• /
• pp.278-281
• /
• 2011

Mobile devices equipped with various sensors have the potential of providing context-aware services. Location is one of the most common forms of context, which can be applied to diverse applications. In this paper, we present methods for learning and predicting users' routes between significant locations, e.g., home and workplaces, based on personal GPS data. A user's significant locations and routes between them are learned by a set of rules as well as clustering. When the user is moving, our methods can predict which of the learned routes is being taken now. After the route prediction, the user's next location can also be inferred. Our methods have been applied to the real GPS datasets from four subjects. For the next location prediction task, the achieved accuracy was 84.8%.