• Journal of the Korea Computer Graphics Society
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• v.26 no.1
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• pp.17-25
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• 2020

We present a novel multi-core CPU based parallel algorithm for the cell-connectivity information extraction algorithm, which is one of the preprocessing steps for volume rendering of unstructured grid data. We first check the synchronization issues when parallelizing the prior serial algorithm naively. Then, we propose a 3-step parallel algorithm that achieves high parallelization efficiency by removing synchronization in each step. Also, our 3-step algorithm improves the cache utilization efficiency by increasing the spatial locality for the duplicated triangle test process, which is the core operation of building cell-connectivity information. We further improve the efficiency of our parallel algorithm by employing a memory pool for each thread. To check the benefit of our approach, we implemented our method on a system consisting of two octa-core CPUs and measured the performance. As a result, our method shows continuous performance improvement as we add threads. Also, it achieves up to 82.9 times higher performance compared with the prior serial algorithm when we use thirty-two threads (sixteen physical cores). These results demonstrate the high parallelization efficiency and high cache utilization efficiency of our method. Also, it validates the suitability of our algorithm for large-scale unstructured data.

• Spatial Information Research
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• v.23 no.4
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• pp.13-22
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• 2015

There has been much interest in the VWorld open platform with the addition of a variety of contents or services such as 2D map, 3D terrain, 3D buildings, and thematic map since 2012. However, the VWorld system architecture was not stable for the system overload. For example, the system was stopped due to the rapidly increasing user accesses when the 3D terrain service of the North Korea and the Baekdu mountain was launched at September 2012 and September 2013, respectively. It was because the system architect has just extended the server system and the network bandwidth whenever the rapid increase of user accesses occurs or new service starts. Therefore, this study proposes a new VWorld system architecture that can reliably serve the huge volume of National Spatial Data by applying the new technologies such as CDN, visualization and clustering. Finally, it is expected that the results of this study can be used as a basis for the next VWorld system architecture being capable of a huge volume of spatial data and users.

• Fire Science and Engineering
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• v.24 no.1
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• pp.90-94
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• 2010

In this study it is intended to review the moving characteristics of smoke by performing visualization simulation for the calculation of the optimal smoke exhaust air volume in case a fire occurs in tunnels where transverse ventilation is applied, and to obtain basic data necessary for the design of smoke exhaust systems by deriving optimal smoke exhaust operational conditions under various conditions. As a result of this study, if it was assumed 0 critical velocity in the tunnel, the smoke exhaust air volume was limited within 250 meter in the road-tunnel disaster prevention indicator and the exhaust efficiency was from 55.1% to 95.8% in the result of this study. If the wind velocity is in the tunnel, the exhaust rate intends to increase rapidly and the exhaust efficiency is decreased. In addition, if the wind velocity is increased, the exhaust rate should be increased in compared with the generation rate of smoke in maximum 1.8 or 1.04 times. In this study, when the wind velocity is in the tunnel, the limited exhaust rate is $84m^3/s{\cdot}250m$. And if it was assumed 1.75 m/s critical velocity in the tunnel, the exhaust rate would be defined $393m^3/s{\cdot}250m$($Q_E$ = 80 + 5Ar).

• Spatial Information Research
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• v.22 no.4
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• pp.39-47
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• 2014

The Yeongsan river estuary has a serious water quality problem due to the water stagnation and it is imperative to predict the changes of water quality for mitigating water pollution. EFDC(Environmental Fluid Dynamics Code) model was mainly utilized to predict the changes of water quality for the estuary. The EFDC modeling normally accompanies the large volume of modeling output. For checking the spatial distribution of the modeling results, post-processing for converting of the output is prerequisite and mainly post-processing program is EFDC_Explorer. However, EFDC_Explorer only shows the spatial distribution of the time series and this doesn't support overlay function with other thematic maps. This means the impossible to the connection analysis with a various GIS data and high dimensional analysis. Therefore, this study aims to develop a post-processing system of a EFDC output to use them as GIS layers. For achieving this purpose, a editing module for main input files, and a module for converting binary format into an ASCII format, and a module for converting it into a layer format to use in a GIS based environment, and a module for visualizing the reconfigured model result efficiently were developed. Using the developed system, result file is possible to automatically convert the GIS based layer and it is possible to utilize for water quality management.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.6
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• pp.579-586
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• 2010

Due to the recent development of measuring technology and 3D programs, it has become possible to obtain various spatial data. This study utilizes the 2-dimensional data and 3-dimensional data extraction technology based on the existing empirical and statistical DB. The data obtained from geospatial data technology are integrated with civil engineering BIM to conduct the modeling of the topography of the target region and select the optimum location condition by using the cut and fill balance of the volume of earth. The target area is the land around Tamjin River, Jangheong-gun, Jeolla-do. The 3-dimensional topology linked with 3-dimensional mapping technology by using the orth-image and aerial LiDAR that uses aerial photo of the target area is visualized with Civil3D of AutoDesk. By using Civil3D program, the Thanks to the recent development of measuring technology and 3D programs, target area is analyzed through visualization and related data can be obtained for analysis. The method of using civil engineering BIM enables to obtain various and accurate information about the target area which is helpful for addressing the issues risen from the existing methodology. In this regard, it aims at searching for the alternatives and provides suggestions to utilize the information.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1316-1320
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• 2009

Since most information is readily available these days, the shear volume of the information simply overwhelms people, rather than helping them as a form of useful knowledge. Thus, the quantity of information someone owns doesn't possess much significance. The possibility to well-utilize the quality information is much more important these days. Electronic culture map service is being provided these days to introduce various cultural information to people around the world. But its service is limited to 'visualization, collection, and integration of the data.' Which means, electronic culture maps are no more than a simple data collector. The main purpose of this thesis is to develop a new kind of knowledge/information service method which overcomes these shortcomings. To achieve this goal, at first, the thesis will take a close look at the characteristics and functions of Chosunjock culture maps, and then, it will clarify the definition of data, information, knowledge of cultural resources. And secondly, nd thirdly, the thesis will look up the Wayfinding contents, User Experience Design, User Context, and Organic design for knowledge/information service. And lastly, the thesis will develop the knowledge/information service, specifically based on Chosunjock cultural resources.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.176-186
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• 2017

The subject of this study is to search for the improvements or solutions of problems in the field of the performing arts that relies on public support and faces economic difficulties. Considering the value chain for the performing arts industry is comprised of Creation-Distribution-Consumption is isolated relatively, this study aims to identify improvements for the distribution system. By examining the government's theater-oriented support policy, this study details methods of improvements in the distribution sector of the performing arts industry. Following the study of the performing arts industry and its value chain, the study analyzes the structure, factors and the present state in the performing arts industry, as well as the volume and type of public sector support for distribution. The study concludes by suggestingmagnifying government's Distribution sector supporting that was limited by only 2.7% in 2014, and fostering and specialty improvement of circulation agents such as production agencies.In addition, supporting distribution diversification, namely the extension of platforms like the Visualization of Performing Arts, is needed. These alternatives will contribute to balanced development and coevolution of each sector which comprises the performing arts industry's value chain.

• Journal of Chest Surgery
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• v.32 no.2
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• pp.164-170
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• 1999

Background: The diffuse infiltrative lung disease often requires biopsy for its final diagnosis. Unlike the limited exposure that can be achieved through small thoracotomy incisions in open lung biopsy technique, the thoracoscopic approach allows visualization and biopsy of nearly entire surface of the lung without morbidity of large standard thoracotomy. The purpose of this study was to compare the diagnostic efficacy and operative safety of thoracoscopic lung biopsy(TLB) with open lung biopsy(OLB) in the diagnosis of diffuse infiltrative lung disease. Material and Method: From March 1993 to August 1997, 81 patients were referred for diagnostic lung biopsy. 51 of them underwent standard open lung biopsy and the remaining 30 patients underwent thoracoscopic lung biopsy. Result: Mean operative time was 63 minutes for TLB and 79 minutes for OLB (p=0.04). The volume of biopsy specimen was not different between two groups(TLB 7.8 cm3, OLB 6.9 cm3 : p=0.72) and the diagnostic accuracy of each methods was comparable (TLB 100%, OLB 96%). The duration of hospital stay was significantly less in TLB (TLB 13days, OLB 22days : p=0.01). The duration of parenteral narcotics administration was also less for TLB(TLB 2.5days, OLB 5.2days, p=0.05). Meanwhile, the duration of chest tube drainage, the frequency of parenteral narcotic injection were not significantly different between two groups. Complications occurred in 2 among the TLB patients (6.67%) and 4 among the OLB patients (7.84%). There was no operative mortality in both groups. Conclusion: We concluded that TLB is a good alternative procedure to OLB in the diagnosis of diffuse infiltrative lung disease with lower morbidity and comparable diagnostic accuracy.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.193-199
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• 1999

Background: Measurement of body temperature is an important parameter in patient management in many clinical conditions. Failure to reach minimal acceptable body temperature standards has been associated with physiological derangements and has necessitated the application of additional therapy. The authors developed a new, simple, accurate thermometry system, which could be used to undertake precise temperature measurement for various clinical conditions. Materials and Methods: A new thermometry system using a specially designed temperature detecting and display system was developed. This system contains a temperature detecting sensor(LM 35CZ), which enables multiple serial checking of heat, data collection and processing computer, and 3-dimensional display system. It provides real time volumetric visualization of temperature distribution of a defined volume and stores and prints the data. Results: With this system, temperature can be measured at multiple interesting sites simultaneously, demonstrated as a 3-dimensional temperature distribution and stored. In well-controlled, systematic experiments a significant correlation has been observed between standard temperature and temperature using this system at various measuring points. Conclusion: This thermometry system is a real-time measurement system, which can demonstrate 3-dimensional heat distribution in experimental phantom and human body and can be used for diagnosing abnormal clinical conditions. In addition, this system reduces the nursing staff work load, providing them more time for long term care to patients.

• Journal of Internet Computing and Services
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• v.15 no.6
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• pp.107-115
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• 2014

Recently, increased use of the internet resulted in generation of large and diverse types of data due to increased use of social media, expansion of a convergence of among industries, use of the various smart device. We are facing difficulties to manage and analyze the data using previous data processing techniques since the volume of the data is huge, form of the data varies and evolves rapidly. In other words, we need to study a new approach to solve such problems. Many approaches are being studied on this issue, and we are describing an effective design and development to build indexing engine of big data platform. Our goal is to build a system that could effectively manage for huge data set which exceeds previous data processing range, and that could reduce data analysis time. We used large SNMP log data for an experiment, and tried to reduce data analysis time through the fast indexing and searching approach. Also, we expect our approach could help analyzing the user data through visualization of the analyzed data expression.