• Journal of the Korean Geographical Society
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• v.43 no.1
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• pp.71-86
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• 2008

The ambiguity of spatial language can be a source of communication problems. For instance, the 'the opposite side' in a sentence such as 'where is the opposite side of building X' can mean more than one direction. Research interests are focused on the directions of a spatial language 'the opposite side'. This study also explored the effect of geometric properties such as reference object's shape and distance from the reference object and spatial reference frame in the comprehension of 'the opposite side'. The assessment tasks used consisted of rating how appropriate the sentence 'where is the opposite side of building X' was to describe a series of pictures. The results of experiment suggest that 'the opposite side' means in most cases more than one direction simultaneously. Changing spatial reference frame has significant effects on individuals' rating of the tasks. However, while reference object's shape (prolonged building) has a consistent effect of the ratings given, the distance from the reference object (shortened road width) has limited influence in comprehending the tasks.

• ETRI Journal
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• v.31 no.1
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• pp.21-30
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• 2009

In low bit-rate video transmission, the payload of a single packet can often contain a whole coded frame due to the high compression ratio in both spatial and temporal domains of most modern video coders. Thus, the loss of a single packet not only causes the loss of a whole frame, but also produces error propagation into subsequent frames. In this paper, we propose a novel whole frame error concealment algorithm which reconstructs the first of the subsequent frames instead of the current lost frame to suppress the effects of error propagation. In the proposed algorithm, we impose a constraint which uses side match distortion (SMD) and overlapped region difference (ORD) to estimate motion vectors between the target reconstructed frame and its reference frame. SMD measures the spatial smoothness connection between a block and its neighboring blocks. ORD is defined as the difference between the correlated pixels which are predicted from one reference pixel. Experimental results show that the proposed algorithm effectively suppresses error propagation and significantly outperforms other conventional techniques in terms of both peak signal-to-noise ratio performance and subjective visual quality.

• ETRI Journal
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• v.29 no.4
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• pp.411-420
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• 2007

The steady evolution of mapping technology is leading to an increasing availability of multi-sensory geo-spatial datasets, such as data acquired by single-head frame cameras, multi-head frame cameras, line cameras, and light detection and ranging systems, at a reasonable cost. The complementary nature of the data collected by these systems makes their integration to obtain a complete description of the object space. However, such integration is only possible after accurate co-registration of the collected data to a common reference frame. The registration can be carried out reliably through a triangulation procedure which considers the characteristics of the involved data. This paper introduces algorithms for a multi-primitive and multi-sensory triangulation environment, which is geared towards taking advantage of the complementary characteristics of spatial data available from the above mentioned sensors. The triangulation procedure ensures the alignment of involved data to a common reference frame. The devised methodologies are tested and proven efficient through experiments using real multi-sensory data.

• Korean Journal of Cognitive Science
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• v.22 no.1
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• pp.19-38
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• 2011

When quantitative representation and reasoning about space is difficult or impossible in a real world, we can use qualitative representation and reasoning. RCC-8 is a well-known qualitative method for 2D space. RCC-8, in which a basic ontological primitive entity for space is a region, shows the connection-based logics and the conceptual neighbors and transitions of topological status between two regions. The transitions happen by changing position or size of regions. However, more aspects have to be considered for representing and reasoning of the world. We propose a modified and extended method QSR-14 for qualitative spatial representation and reasoning of a dynamic physical 2D world in the gravitation field. We mention the need of a global reference frame and describe QSR-14 in detail for representing and reasoning of physical and chemical changes of a real world using the global reference frame. We believe QSR-14 is appropriate for the qualitative spatial representation and reasoning of a dynamic physical world. The usefulness of QSR-14 is shown with several examples.

• Spatial Information Research
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• v.18 no.3
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• pp.73-83
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• 2010

This study presents a method to segment an image, employing the statistics observed at each pixel location across sequential frame images. In the acquisition and analysis of spatial information, utilization of digital image processing technique has very important implications. Various image segmentation techniques have been presented to distinguish the area of digital images. In this study, based on the analysis of the spectroscopic characteristics of sequential frame images that had been previously researched, an image segmentation method was proposed by using the randomness occurring among a sequence of frame images for a same scene. First of all, we computed the mean and standard deviation values at each pixel and found reliable pixels to determine seed points using their standard deviation value. For segmenting an image into individual regions, we conducted region growing based on a T-test between reference and candidate sample sets. A comparative analysis was conducted to assure the performance of the proposed method with reference to a previous method. From a set of experimental results, it is confirmed that the proposed method using a sequence of frame images segments a scene better than a method using a single frame image.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2113-2115
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• 2006

This paper proposes a spatio-temporal correlation algorithm that takes advantage of the spatial and temporal correlations in video streams for error concealment. The spatio-temporal correlation algorithm sets the neighborhood area of the damaged part as a reference window, then finds the area that best matches the reference window in the previous frame. The best-matched area in the previous frame replaces the damaged part in the current frame. The results of ten variations of the proposed algorithm are compared with conventional error concealment methods. These methods include the ones applicable to P-frames as well as I-frames. The comparison results show that the proposed algorithm is very efficient for l-frame error concealment with a large motion between frames.

• Steel and Composite Structures
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• v.34 no.5
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• pp.715-732
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• 2020

High-strength steel composite Y-eccentrically braced frame (Y-HSS-EBF) is a novel structural system. In this study, the spatial substructure hybrid simulation test (SHST) method is used to further study the seismic performance of Y-HSS-EBF. Firstly, based on the cyclic loading tests of two single-story single-span Y-HSS-EBF planar specimens, a finite element model in OpenSees was verified to provide a reference for the numerical substructure analysis model for the later SHST. Then, the SHST was carried out on the OpenFresco test platform. A three-story spatial Y-HSS-EBF model was taken as the prototype, the top story was taken as the experimental substructure, and the remaining two stories were taken as the numerical substructure to be simulated in OpenSees. According to the test results, the validity of the SHST was verified, and the main seismic performance indexes of the SHST model were analyzed. The results show that, the SHST based on the OpenFresco platform has good stability and accuracy, and the results of the SHST agree well with the global numerical model of the structure. Under strong seismic action, the plastic deformation of Y-HSS-EBF mainly occurs in the shear link, and the beam, beam-columns and braces can basically remain in the elastic state, which is conducive to post-earthquake repair.

• Journal of Broadcast Engineering
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• v.17 no.5
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• pp.716-724
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• 2012

In this paper, we propose a fast decision method of maximum coding depth decision and reference frame selection in HEVC. To reduce computational complexity and encoding time of HEVC, two methods are proposed. In the first method, the maximum depth of each coding unit (CU) in a largest CU (LCU) is constrained by using the maximum coding depth used by adjacent LCUs based on the assumption that the spatial correlation is very high and rate-distortion (R-D) cost. And we constrain the number of reference pictures for prediction unit (PU) performing motion estimation by using the motion information of the upper depth PU. The proposed methods reduce computational complexity of the HEVC encoder by constraining the maximum coding depth and the reference frame. We could achieve about 39% computational complexity reduction with marginal bitrate increase of 1.2% in the comparison with HM6.1 HEVC reference software.

• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.789-796
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• 2012

Fingerprinting is a widely used positioning technology for received signal strength (RSS) based wireless local area network (WLAN) positioning system. Though spatial RSS variation is the key factor of the positioning technology, temporal RSS variation needs to be considered for more accuracy. To deal with the spatial and temporal RSS characteristics within a unified framework, this paper proposes an extended signal propagation mode (ESPM) and a fingerprint generation method. The proposed spatiotemporal fingerprint generation method consists of two algorithms running in parallel; Kalman filtering at several measurement-sampling locations and Kriging to generate location fingerprints at dense reference locations. The two different algorithms are connected by the extended signal propagation model which describes the spatial and temporal measurement characteristics in one frame. An experiment demonstrates that the proposed method provides an improved positioning accuracy.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.372-378
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• 2010

This paper propose the fast motion estimation algorithm with adaptive search range adjustment using motion activities of temporal and spatial neighbor blocks. The existing fast motion estimation algorithms with adaptive search range adjustment use the maximum motion vector of all blocks in the reference frame. So these algorithms may not control a optimum search range for slow moving block in current frame. The proposed algorithm use the maximum motion vector of neighbor blocks in the reference frame to control a optimum search range for slow moving block. So the proposed algorithm can reduce computation time for motion estimation. The experiment results show that the proposed algorithm can reduce the number of search points about 15% more than Simple Dynamic Search Range(SDSR) algorithm while maintaining almost the same bit-rate and motion estimation error.