• The Journal of the Acoustical Society of Korea
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• v.23 no.2
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• pp.109-116
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• 2004

This paper deals with data association using 3 sets of passive linear array sonars (PUS) geometrically positioned in a Y-shaped configuration, but fixed in an underwater environment. The data association problem is directly transformed into a 3-D assignment problem, which is known to be NP-hard. For generic passive sensors, it can be sotted using conventional algorithms, while it in PLAS becomes a formidable task due to the presence of bearing ambiguity. In particular, we proposed data association method robust to bearing measurements errors by incorporating frequency information and analyze a region of ghost problem by geometrical relation PUS and target. We analyzed the effectiveness of the proposed method by representative simulation in multi-target.

• Journal of Astronomy and Space Sciences
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• v.35 no.2
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• pp.83-92
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• 2018

The summer polar lower thermosphere (90-100 km) has an interesting connection to meteors, adjacent to the mesopause region attaining the lowest temperature in summer. Meteors supply condensation nuclei for charged ice particles causing polar mesospheric summer echoes (PMSE). We report the observation of meteor trail with nearly horizontal transit at high speed (20-50 km/s), and at last with re-enhanced echo power followed by diffusive echoes. Changes in phase difference between radar receivers aligned in meridional and zonal directions are used to determine variations in horizontal displacements and speeds with respect to time by taking advantage of radar interferometric analysis. The actual transit of echo target is observed along the straight pathway vertically and horizontally extended as much as a distance of at least 24 km and at most 29 km. The meteor trail initially has a signature similar to 'head echoes', with travel speeds from 20 - 50 km/s. It subsequently transforms into a different type of echo target including specular echo and then finally the power reenhanced. The reenhancement of echo power is followed by fume-like diffusive echoes, indicating sudden release of plasma as like explosive process probably involved. We discuss a possible role of meteor-triggered secondary plasma trail, such as fireball embedded with electrical discharge that continuously varies the power and transit speed.

• Journal of Korean Society of Rural Planning
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• v.20 no.3
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• pp.45-53
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• 2014

This study classifies the types of visitors to experiential fishing villages and analyses the features and target marketing strategies by categorical groups. Seven factors are extracted by Factor Analysis and the results of Cluster Analysis indicate the classification of five groups. The first group puts emphasis on the family connection, so family centered facilities and programs are necessary. The second group is composed of surrounding area residents whose purpose of visit is unclear. So environmentally friendly village development programs to encourage local patriotism are necessary. The third group puts emphasis on the necessary facilities and programs for experiencing the fishing village and traditional play, etc. The fourth group emphasizes programs related with the region and the means to satisfy visitor's aesthetic desires. Finally, the fifth group aims at various desires that are generally felt in experiential fishing villages. So this group requires marketing strategies from the public point of view. The existing research mostly surveys rural tourism villages, but this study highlights the difference in dealing with fishing villages as opposed to rural villages, from the perspective of industry and settlement.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.10
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• pp.620-629
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• 2005

In this paper, a new protocol-based approach was proposed for development of a ubiquitous vision system. It is possible to apply the approach by regarding the ubiquitous vision system as a multiagent system. Thus, each vision sensor can be regarded as an agent (vision agent). Each vision agent independently performs exact segmentation for a target by color and motion information, visual tracking for multiple targets in real-time, and location estimation by a simple perspective transform. Matching problem for the identity of a target during handover between vision agents is solved by the Identified Contract Net (ICN) protocol implemented for the protocol-based approach. The protocol-based approach by the ICN protocol is independent of the number of vision agents and moreover the approach doesn't need calibration and overlapped region between vision agents. Therefore, the ICN protocol raises speed, scalability, and modularity of the system. The protocol-based approach was successfully applied for our ubiquitous vision system and operated well through several experiments.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.55-64
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• 2002

This analysis is accomplished by using 331 rescue and medical evacuation cases performed by KangWonDo Fire Service Department Aviation(KFSA-119 Heicopters) between Jan. 1998 and Oct. 2002. By analysing injury causes, annual differences, sexual, scenic(locaional) distribution and wounded part distribution, this study tried to figure out the general tendency of the helicopter-transported patients in Korea. The results are as follows; 1. The whole population of the patients rescued and transported by helicopters is increasing by the annual rate of 150%~200%. 2. For the locational (scenic) distribution of the patients, 57% (190 cases) of the target population were injured on their mountain-climbing or tracking. 3. 12% (41 cases) of the target population were the Inter-Hospital transport cases. 4. 6% (16 cases) were the expired cases. 5. for the wounded part distribution, 46% (106 cases) were muscular skeletal injuries. 6. The aircraft and personnel of the KFSA were rescue-oriented, so for the EMS operations especially inter-hospital transport missions, different medical equipments and personnels are needed.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.9
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• pp.838-842
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• 2007

A brain-computer interface(BCI) system is a communication channel which transforms a subject's thought process into command signals to control various devices. These systems use electroencephalographic signals or the neuronal activity of many single neurons. The presented study deals with an efficient analysis method of neuronal signals from a BCI System using an independent component analysis(ICA) algorithm. The BCI system was implemented to generate event signals coding movement information of the subject. To apply the ICA algorithm, we obtained the perievent histograms of neuronal signals recorded from prefrontal cortex(PFC) region during target-to-goal(TG) task trials in the BCI system. The neuronal signals were then smoothed over 5ms intervals by low-pass filtering. The matrix of smoothed signals was then rearranged such that each signal was represented as a column and each bin as a row. Each column was also normalized to have a unit variance. As a result, we verified that different patterns of the neuronal signals are dependent on the target position and predefined event signals.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.281-287
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• 2003

A Natural cavities were found at shallow depth during construction of a huge bridge in Moon-Kyung, Korea. The distribution patterns of cavities in the Moon-Kyung limestone were investigated carefully with a supplementary field job such as a structural geological survey, a geophysical survey, and a rock mechanical test in laboratory or field. A structural geological mapping produced a detail geological map on this area. It suggested that there were three faults in this area, and these faults had an influence on the mechanism of natural cavities. Among many kinds of geophysical surveys, an electrical resistivity prospecting was applied firstly on the specific area that was selected by results from the geological survey. Many evidences for cavities were disclosed from this geophysical data. Therefore, a seismic tomography was tested on the target area, which was focused by results from the electrical resistivity prospecting and was believed to have several large cavities. A distinct element numerical simulation using the UDEC was followed on the target area after completing all of field surveys. Data from field tests were directly dumped or extrapolated to numerical simulations as input data. It was verified from numerical analysis that several natural cavities underneath the foundation of the bridge should be reinforced. Based on the project result, finally, most of foundations for the bridge were re-examined and the cement grouting reinforcement was constructed on several foundations among them.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.973-984
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• 2007

This study developed and calculated alternative evaluation index (AEI) from the effectiveness analyses of alternatives for rehabilitation of distorted hydrologic cycle. The feasible alternatives for the poor-conditioned region in the Anyangcheon watershed were proposed and quantitatively analyzed using continuous water quantity/quality simulation model, Hydrological Simulation Program-Fortran (HSPF). The effectiveness analyses include 355th flow and 275th flow of flow duration curve and number of increased days to satisfy the target monthly flow for water quantity and BOD average concentration, total daily loads and number of increased days to satisfy the target concentration and total daily loads. The feasible alternatives are restoration of covered stream, prevention of streamflow loss through sewers, redevelopment of existing reservoir, reuse of treated wastewater, use of groundwater collected by subway stations and construction of small wastewater treatment plant. Therefore, alternative priority ranking was derived from AEIs. It will be effective to make an integrated watershed management for sustainable development.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.15-15
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• 2003

To discover new drugs more quickly and more efficiently, pharmaceutical companies and biotechnology firms are increasingly turning to the genomics and the structural proteomics technologies. Structural-proteomics can provide a foundation for this through the determination and analysis for protein structure on a genomics scale. Among many structures determined by CGI, we will present with the representative examples drawn from our work on novel structures or complex structures of the disease-related proteins. The alpha subunit of Hypoxia-inducible factor (HIF) is targeted for degradation under normoxic conditions by an ubiquitin-ligase complex that recognizes a hydroxylated proline residue in HIF. Hydroxylation is catalysed by HIF prolyl 4-hydroxylases (HIFPH) which are fe(II) and 2-oxoglutarate (2-OG) dependent oxygenases. Here, we discuss the first crystal structure of the catalytic domain of HIFPH in complexes, with the Fe(II)/2-OG at 1.8Å. These structures suggest that the Ll region (residues 236-253), which is also conserved in mammals, form a 'lid' that closes over the active site. The structural and mutagenesis analyses allow us to provide a focus for understanding cellular responses to hypoxia and a target for the therapeutic manipulation.

• Journal of Information Science Theory and Practice
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• v.4 no.1
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• pp.6-20
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• 2016

Scholarly communication plays a significant role in the development and dissemination of research outputs in library and information science (LIS). This study presents findings from a survey which examines the key attributes that characterize the publishing by Pakistani LIS scholars, i.e. academics and professionals, in national journals. A pilot-tested, electronic questionnaire was used to collect the data from the target population. 104 respondents (or 69.3% of target) provided feedback on areas such as number of articles published, number of citations, and the nature of any collaboration with other authors. The findings of this survey revealed that, among the various designated regions of Pakistan, the Punjab region was the most highly represented. In articles published in national journals, there was a clear preference among all respondents to collaborate with at least one other author. The citation metrics for LIS articles in national journals were relatively low (30.22%), which aligns with Scimago’s Journal and Country Rankings. The uptake of social scholarly networks mirrors international trends. Respondents were asked to score factors which could impact negatively on their ability to undertake research and/or publish the results. The study recommends that concerned stakeholders work together, as appropriate, to address concerns. In addition, it recommends that further research be undertaken to define patterns of Pakistani co-authorship in the social sciences.