• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.152.1-152
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• 2001

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.9
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• pp.736-743
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• 2013

In IRST(infrared search and track) system, the small target detection is very difficult because the IR(infrared) image have various clutter and sensor noise. The noise and clutter similar to the target intensity value produce many false alarms. In this paper. We propose the adaptive detection method which obtains optimal target detection using the image intensity information and the prior information of target. In order to enhance the target, we apply the human visual system. we determine the adaptive threshold value using image intensity and distance measure in target enhancement image. The experimental results indicate that the proposed method can efficiently extract target region in various IR images.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1131-1134
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• 1999

In general CELP type vocoders provide good speech quality around 4.8kbps. Among them, G.723.1 developed for Internet Phone and videoconferencing includes two vocoders, 5.3kbps ACELP and 6.3kbps MO-MLQ. Since 6.3kbps MP-MLQ requires large amount of computation for fixed codebook search, it is difficult to realize real time processing. In order to improve the problem this paper proposes the new method that reduces the processing time up to about 50% of codebook search time. We first decide the grid bit, then search the codebook. Grid bit is selected by comparison between synthetic speech, which is synthesized with only odd or even pulses of target vector. and DC removed original speech. As a result, we reduced the total processing time of G.723.1 MP-MLQ up to about 26.08%. In objective quality test 11.19㏈ of segSNR was obtained, and in subjective quality test there was almost no speech degradation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.708-711
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• 2011

The Navy is in the process of developing a sonar-operation strategy to increase the effectiveness of underwater target seeking capability. HMS is the basic strategy to detect underwater targets. The advantages of HMS is that, it has a short preparation time to operate and can be always used regardless of sea conditions and weather. However, it is difficult to effectively detect underwater targets due to the interaction between marine environments and sonar-operations. During the research, the effectiveness of the HMS system's underwater target seeking capability was analyzed by integrating various search patterns and environment conditions into the simulation. In the simulation the ship target an evasive target within a set region. The simulation presented results for an effective searching methods of underwater targets. These research results can be used as foundation for advancing and improving the sonar operational tactics.

• Korean Journal of Cognitive Science
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• v.22 no.2
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• pp.103-121
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• 2011

This study investigated how spatial dimension information and dimensional consistency between learning and testing phase would influence the target search performance. The participants learned spatial layouts of Lego blocks shown in either two- (2D) or three-dimension (3D) and were tested with the rotated stimuli ($0^{\circ}$, $90^{\circ}$, $180^{\circ}$, or $270^{\circ}$ from the initial view) in consistent or inconsistent dimension. Significantly better performance was observed when initial learning display appeared in 2D than in 3D. Particularly, the participants showed difficulties in flexible usage of spatial information presented in 3D especially if the dimensional information in the testing phase also was 3D and required mental rotation. The present study indicates that spatial map presented in 2D may be more useful than 3D in driving situations in which acquired spatial information from navigating device, such as GPS, and location of driver continuously changes.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.195-202
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• 2005

An adaptive segmentation algorithm is used to efficiently target decisions in local non-stationary images. Until now, several adaptive approaches have been proposed as a method of segmentation. However, they can't be directly used for radar target detection because a radar signal has different characteristics from general images. Generally, a histogram of radar signal shows that targets have a relatively small number of frequency functions compared to the background and distribution of background, which have several shapes as the environment changes. In this paper, we propose an adaptive segmentation algorithm using a histogram chord which is a right-down line from maximum pick of frequency function. The proposed method provides thresholds which are optimum for several radar environments because the used chord for threshold search is not significantly effected by interference conditions. Simulation results show that the proposed method is superior to the traditional algorithms, global threshold method and distribution median method, with respect to detection performance.

• Journal of the Korean Society of Marine Environment & Safety
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• v.6 no.1
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• pp.111-120
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• 2000

In this study the drift prediction models currently used in search and rescue(SAR) operations are introduced and the basic differences among them are analyzed by comparing the target classification, the treatment of environmental conditions, leeway equations and the determination of search area. In addition the new methods under development including AP98 of U.S. Coast Guard are compared and studied to improve the efficiency of SAR operation.

• The Journal of the Acoustical Society of Korea
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• v.19 no.7
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• pp.7-14
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• 2000

In this paper, we propose a near-field target localization algorithm using a bottom-mounted linear sensor amy in a multipath environment. In a multipath environment, the conic angles of a target signals through each path are different, and the position of the target can be estimated using these conic angles and the time difference of these signals. We derive equations on the relation of time-difference of signals and conic angles estimates under the far-field assumption, and estimate the position of target by simultaneously solving these equations. For a certain geometry of a target and the sensor array, there exist cases when the conic angles are very close. In such a case, we estimate the position of the target using an additional 1-D search.

• Journal of Information Technology Services
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• v.17 no.2
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• pp.129-142
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• 2018

Recently, the number of patent applications have been increasing rapidly every year as the importance of protecting intellectual property rights becomes more important. Patents must be inventive and have novelty. Especially, the novelty implies that the corresponding invention is not the same as the previous invention. To confirm the novelty, prior art search must be conducted before and after the application. The target of prior art search should include not only Korean patents but also foreign patents. Search of foreign patents should be supported by multilingual search techniques. However, a dictionary-based naive approach shows a limitation because some technical concepts are represented in different terms according to each nation. For example, a Korean term and a Japanese term may not be synonym even though they represent the same technical concept. In this paper, we propose a new method to map semantic similarity between technical terms in Korean patents and Japanese patents. To investigate different representations in each nation for the same technical concept, we identified and analyzed pairs of patents those are mutually connected with priority claim relationship. By performing an experiment with real-world data, we showed that our approach can reveal semantically similar technical terms in other language successfully.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1299-1302
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• 2003

In this paper, we propose new method which can provide user the path to the target place efficiently. It stores the state of roads to target place as the form of Q-table and finds the proper path using Q-table.0-table is updated by the information about real traffic which is reported by users. This method can provides the proper path, using less storage and less computation time than the conventional method which stores entire road traffic information and finds the path by graph search algorithm.