• Journal of Korea Game Society
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• v.11 no.1
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• pp.47-57
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• 2011

Mobile based location-based service can normally be classified into four categories according to their dimensions of their screen layout: map-based, bird-eye view based, photo-based, and video-based. Specifically, video-based layout system combining AR technology has a appealing factor to users through the reality-based presence but normally requires sophisticated real-time image matching algorithms to represent the system. This paper provides a new location-based service by introducing mirror world to resolve the problem and implements its prototype. The proposed service does not need such algorithm and will effectively be useful for users to get the reality of the presence for any locations which is regardless of a user's real location.

• Journal of Korea Multimedia Society
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• v.5 no.2
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• pp.141-146
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• 2002

This paper proposed the automated methods for th detection of mass. We analysed characteristic of mass by using the features on mammograms. In first step, the homogeneity was used to distinguish mass from the normal tissue. In second step, we examined the dualistic circularity and pixel distribution of candidates from the dualistic images of each candidates in which we regards the gray value as topographic height information. The final decision was done with the method in which each candidates is compared with the hemispheric template. Template matching method was used in comparing the priority of candidates with the spacial circularity which is the characteristic of the mass, We applied the algorithm to the 180 mammograms. The detection resulted that the sensitivity of the proposed methods was 95.51% in which we detected 85 from the 89 mammograms.

• Journal of Korea Multimedia Society
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• v.3 no.4
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• pp.356-364
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• 2000

Block based fast motion estimation algorithm use the fixed search pattern to reduce the search point, and are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search region we are likely to find local minima instead of the global minimum and highly rely on the initial search points. This situation is evident in the motion boundary. In this paper we define the candidate regions within the search region using the motion information of the neighbor blocks and we propose the multiple local search method (MLSM) which search for the solution throughout the candidate regions to reduce the possibilities of isolation to the local minima. In the MLSM we mark the candidate region in the search point map and we avoid to search the candidate regions already visited to reduce the calculation. In the simulation results the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary. Especially, in PSNR the proposed method obtains similar estimate accuracy with the significant reduction of search points to that of full search.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.4
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• pp.539-547
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• 2011

In this paper, a method of generating path planning map is developed using digitalized geographic information such as FDB(Feature DataBase). FDB is widely used by the Army and needs to be applied to all weapon systems of newly developed. For the autonomous navigation of a robot, it is necessary to generate a path planning map by which a global path can be optimized. First, data included in FDB is analyzed in order to identify meaningful layers and attributes of which information can be used to generate the path planning map. Then for each of meaningful layers identified, a set of values of attributes in the layer is converted into the traverse cost using a matching table in which any combination of attribute values are matched into the corresponding traverse cost. For a certain region that is gridded, i.e., represented by a grid map, the traverse cost is extracted in a automatic manner for each gird of the region to generate the path planning map. Since multiple layers may be included in a single grid, an algorithm is developed to fusion several traverse costs. The proposed method is tested using a experimental program. Test results show that it can be a viable tool for generating the path planning map in real-time. The method can be used to generate other kinds of path planning maps using the digitalized geographic information as well.

• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.2262-2270
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• 1999

In this paper, we describe gesture recognition algorithm using computer vision sensor and HMM. The automatic hand region extraction has been proposed for initializing the tracking of the tele-operation gestures. For this, distance informations(disparity map) as results of stereo matching of initial left and right images are employed to isolate the hand region from a scene. PDOE(positive difference of edges) feature images adapted here have been found to be robust against noise and background brightness. The KNU/KAERI(K/K) gesture instruction set is defined for tele-operation in atomic electric power stations. The composite recognition model constructed by concatenating three gesture instruction models including pre-orders, basic orders, and post-orders has been proposed and identified by discrete HMM. Our experimental results showed that consecutive orders composed of more than two ones are correctly recognized at the rate of above 97%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3C
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• pp.288-296
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• 2009

In POCS (projection onto convex sets)-based reconstruction of HR (high resolution) image, the quality of reconstructed image is gradually improved through iterative motion estimation and image restoration. The amount of computation, however, increases because of the repeated inter-frame motion estimation. In this paper, an HR reconstruction algorithm is proposed where modified ARPS (adaptive rood pattern search) and POCS are simultaneously performed. In the modified ARPS, the motion estimates obtained from phase correlation or from the previous steps in POCS restoration are utilized as the initial reference in the motion estimation. Moreover, estimated motion is regularized with reference to the neighboring blocks' motion to enhance the reliability. Computer simulation results show that, when compared to conventional methods which are composed of full search block matching and POCS restoration, the proposed method is about 30 times faster and yet produces HR images of almost equal or better quality.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.1
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• pp.8-17
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• 1998

This paper presents a method of construction and re-use of a GCP database for precision geometric correction of high resolution satellite images. Accurate geometric correction can be achieved by using accurate GCPs. The GCP information which is extracted from maps or other sources is saved in a database in conjunction with the corresponding image chips. The usage of the GCPs from the database gives reusability and efficiency in marking new GCPs. An image matching algorithm was developed to determine the corresponding positions between an image chip and a new image. The proposed technique can save time in the regular operation of satellite image preprocessing by propagating the pre-determined GCPs to the new image correction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4A
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• pp.364-370
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• 2002

In this paper, we propose a VLSI array architecture for high speed processing of FBMA. First of all, the sequential FBMA is transformed into a single assignment code by using the index space expansion, and then the dependance graph is obtained from it. The two dimensional VLSI array is derived by projecting the dependance graph along the optimal direction. Since the candidate blocks in the search range are overlapped with columns as well as rows, the processing elements of the VLSI array are designed to reuse the overlapped data. As the results, the number of data inputs is reduced so that the processing performance is improved. The proposed VLSI array has (N$^2$+1)${\times}$(2p+1) processing elements and (N+2p) input ports where N is the block size and p is the maximum search range. The computation time of the rat reference block is (N$^2$+2(p+1)N+6p), and the block pipeline period is (3N+4p-1).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.5
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• pp.505-513
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• 2010

The tribrachial flame has attracted interest as a basic structure of the flame edge. This flame structure helps understand stabilization of laminar flames and re-ignition of turbulent flames. A number of analytical and experimental studies have been carried out on the tribrachial flame. However, the effect of the variation of the flammability limits on the structure of the tribrachial flame has not been studied in detail. In this study, the effect of non-symmetric flammability limits on the flame structure was investigated by adopting a simple numerical scheme based on several laminar flame theories. A fixed velocity field was considered and boundary matching algorithm was used on the premixed branch. The variation of the diffusion branches under the non-symmetric flammability limits and heat loss was investigated. The formation and extinction of the diffusion branch behind the premixed branch were successfully described. This basic study can help understand the fundamental structure of the flame and can form the basis of subsequent detailed studies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.10
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• pp.1219-1227
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• 2013

A new type of wearable robot is developed for a disabled person with disabled limbs, that is, a person who cannot intentionally move his/her legs and arms. This robot can enable the disabled person to grip an object using eye movements. A gaze tracking algorithm is employed to detect pupil movements by which the person observes the object to be gripped. By using this gaze tracking 2D information, the object is identified and the distance to the object is measured using a Kinect device installed on the robot shoulder. By using several coordinate transformations and a matching scheme, the final 3D information about the object from the base frame can be clearly identified, and the final position data is transmitted to the DSP-controlled robot controller, which enables the target object to be gripped successfully.