• International Journal of Contents
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• 제10권4호
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• pp.69-74
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• 2014

General location aware systems are only applied to indoor and outdoor environments using more than three transmitters to estimate a fixed object location. Those kinds of systems have environmental restrictions that require an already established infrastructure. To solve this problem, an Object Location Estimation (OLE) algorithm based on PTP (Point To Point) communication has been proposed. However, the problem with this method is that deduction of performance parameters is not enough and location estimation is very difficult because of unknown restriction conditions. From experimental tests in this research, we determined that the performance parameters for restriction conditions are a maximum transmission distance of CSS communication and an optimum moving distance interval between personal locations. In this paper, a system applied OLE algorithm based on PTP communication is implemented using a CSS (Chirp Spread Spectrum) communication module. A maximum transmission distance for CSS communication and an optimum moving distance interval between personal locations are then deducted and studied to estimate a fixed object location for generalization.

• Architectural research
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• 제12권2호
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• pp.15-22
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• 2010

Our prediction model is based on the development of "Semantic Location Model." It embodies geometrical and topological information which can increase the efficiency in prediction and make it easy to manipulate the prediction model. Data mining is being implemented to extract the inhabitant's location patterns generated day by day. As a result, the self-learning system will be able to semantically predict the inhabitant's location in advance. This context-aware system brings about the key component of the ubiquitous computing environment. First, we explain the semantic location model and data mining methods. Then the location prediction model for the ubiquitous computing system is described in details. Finally, the prototype system is introduced to demonstrate and evaluate our prediction model.

• 로봇학회논문지
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• 제12권3호
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• pp.249-257
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• 2017

This paper proposes a method to segment urban scenes semantically based on location prior information. Since major scene elements in urban environments such as roads, buildings, and vehicles are often located at specific locations, using the location prior information of these elements can improve the segmentation performance. The location priors are defined in special 2D coordinates, referred to as road-normal coordinates, which are perpendicular to the orientation of the road. With the help of depth information to each element, all the possible pixels in the image are projected into these coordinates and the learned prior information is applied to those pixels. The proposed location prior can be modeled by defining a unary potential of a conditional random field (CRF) as a sum of two sub-potentials: an appearance feature-based potential and a location potential. The proposed method was validated using publicly available KITTI dataset, which has urban images and corresponding 3D depth measurements.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.381-385
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• 2007

As development of wireless communication technology has promoted mobility, Location Based Service (LBS) became embossed. The LBS is a service to recognize and utilize a location of a person or a thing through a device that ensures mobility based on wireless communication network. This paper thus researches on Healthcare Method to respond to emergency rapidly by recognizing a patient's location with the LBS. The LBS also provides location information of a user as well as remote management of organism data such as ECG data or pulse, which is transferred to a hospital or an emergency room.

• Journal of Electrical Engineering and Technology
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• 제3권3호
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• pp.300-307
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• 2008

Event source locating is very important to improving the power quality level. This paper presents a method to determine the relative location of the voltage sag source according to the cause. For this, the concept of the relative location of the source is defined first. Then, the main causes of voltage sag are classified and their characteristics are discussed. From these investigations, the rules to determine the relative location of event source are proposed for each type and the overall algorithm to identify the relative location and the kind of event source is presented. Finally, the proposed method is applied to the IEEE 13-bus test system and it is verified that the method can help to pinpoint the accurate location of the event source.

• 로봇학회논문지
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• 제8권3호
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• pp.206-216
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• 2013

We investigate the role of contact location information on the perception of local features during contour following in a virtual environment. An absolute identification experiment is conducted under force-alone and force-plus-contact-location conditions to investigate the effect of the contact location information. The results show that the participants identify the local features significantly better in terms of higher information transfer for the force-plus-contact-location condition, while no significant difference was found for measures of the efficacy of contour following between the two conditions. Further data analyses indicate that the improved identification of local features with contact location information is due to the improved identification of small surface features.

• Journal of Computing Science and Engineering
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• 제2권2호
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• pp.137-160
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• 2008

The increasing availability of personal location data pushed by the widespread use of location-sensing technologies raises concerns with respect to the safeguard of location privacy. To address such concerns location privacy-preserving techniques are being investigated. An important area of application for such techniques is represented by Location Based Services (LBS). Many privacy-preserving techniques designed for LBS are based on the idea of forwarding to the LBS provider obfuscated locations, namely position information at low spatial resolution, in place of actual users' positions. Obfuscation techniques are generally based on the use of geometric methods. In this paper, we argue that such methods can lead to the disclosure of sensitive location information and thus to privacy leaks. We thus propose a novel method which takes into account the semantic context in which users are located. The original contribution of the paper is the introduction of a comprehensive framework consisting of a semantic-aware obfuscation model, a novel algorithm for the generation of obfuscated spaces for which we report results from an experimental evaluation and reference architecture.

• 한국멀티미디어학회논문지
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• 제6권4호
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• pp.601-609
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• 2003

In wireless mobile networks, the service area is partitioned into several registration areas (RAs). Every RA is associated with a mobility database called Visitor Location Register (VLR). The VLR is used to achieve the location management of the mobile terminals. When a mobile terminal enters a new RA, the VLR stores the current location information of the mobile terminal before serving any mobile services. At that time, if the VLR is full, the registration procedure fails, and the system can not deliver services to the mobile user under the existing cellular technology To resolve this problem, we propose a VLR overflow control scheme considering mobility of mobile users to accomodate incoming users during VLR overflow. The performance of the proposed scheme is evaluated by an analytic model in terms of costs for the location search and the location update, and compared with those of the overflow control scheme proposed by Lin[1].

• International Journal of Contents
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• 제5권2호
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• pp.59-63
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• 2009

Since it is hard to use GPS for tracking mobile user in indoor environments, much research has focused on techniques using existing wireless local area network infrastructure. Signal strength received at a fixed location is not constant, so fingerprinting approach which use pattern matching is popular. But this approach has to pay additional costs to determine user location. This paper proposes a new approach to find user's location efficiently using an index scheme. After analyzing characteristics of RF signals, the paper suggests the data processing method how the signal strength values for each of the access points are recorded in a radio map. To reduce computational cost during the location determination phase, multidimensional indexes for radio map with the important information which is the order of the strongest access points are used.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.437-439
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• 2000

This paper describes a fault location technique using wavelets in underground transmission cable system Estimation of fault location is performed using data sampled at two ends of underground system. In the case of 50% fault of total underground transmission line, fault location is calculated using sampled single-end data in underground transmission line. Traveling wave is utilized in capturing the travel time of the transients along the monitored lines between the relay and the fault point. This travel time information is provided by the wavelet. Simulation was performed using EMTP. ATP Draw and MATLAB. The results of fault location shown in this paper will be evaluated as an effective suggestion for fault to location in real underground transmission line.