• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.414-432
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• 2012

Land price is a kind of text to read urban spatial structure. The purpose of this paper is to inquire into the characteristics of Daegu's urban structure and its change in time through exploring spatio-temporal variations of land price with a detailed spatial and temporal resolution. To achieve this, land value surfaces were represented using the officially assessed land price every other year from 1995 to 2011. Through mapping and exploring spatio-temporal patterns and fluctuation rates of land price for this period, changes in urban structure, the effects of local decision makings such as Greenbelt adjustment, housing site development, and gentrification, and the effects of business fluctuations or policies at global or national scales could be caught. In addition, the trends for suburbanization and multi-centric urban form could be examined from the results of a negative exponential model explaining the effect of distance from an urban center on spatial variation of land price. These results demonstrate that urban analysis using land price mirroring spatial decision making at various scales could deepen understanding for internal structure and change of a city and provide useful information for establishing regional and urban development policies and evaluating their effects.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.39.2-39.2
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• 2010

In this paper, I present the domestic development of near infrared camera systems for the ground telescope and the space satellite. These systems are the first infrared instruments made for astronomical observation in Korea. KASINICS (KASI Near Infrared Camera System) was developed to be installed on the 1.8m telescope of the Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. KASINICS is equipped with a $512{\times}512$ InSb array enable L band observations as well as J, H, and Ks bands. The field-of-view of the array is $3.3'{\times}3.3'$ with a resolution of 0.39"/pixel. It employs an Offner relay optical system providing a cold stop to eliminate thermal background emission from the telescope structures. From the test observation, limiting magnitudes are J=17.6, H=17.5, Ks=16.1 and L(narrow)=10.0 mag at a signal-to-noise ratio of 10 in an integration time of 100 s. MIRIS (Multi-purpose InfraRed Imaging System) is the main payload of the STSAT-3 in Korea. MIRIS Space Observation Camera (SOC) covers the observation wavelength from $0.9{\mu}m$ to $2.0{\mu}m$ with a wide field of view $3.67^{\circ}{\times}3.67^{\circ}$. The PICNIC HgCdTe detector in a cold box is cooled down below 100K by a micro Stirling cooler of which cooling capacity is 220mW at 77K. MIRIS SOC adopts passive cooling technique to chill the telescope below 200K by pointing to the deep space (3K). The cooling mechanism employs a radiator, a Winston cone baffle, a thermal shield, MLI of 30 layers, and GFRP pipe support in the system. Opto-mechanical analysis was made in order to estimate and compensate possible stresses from the thermal contraction of mounting parts at cryogenic temperatures. Finite Element Analysis (FEA) of mechanical structure was also conducted to ensure safety and stability in launching environments and in orbit. MIRIS SOC will mainly perform the Galactic plane survey with narrow band filters (Pa $\alpha$ and Pa $\alpha$ continuum) and CIB (Cosmic Infrared Background) observation with wide band filters (I and H) driven by a cryogenic stepping motor.

• Atmosphere
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• v.20 no.2
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• pp.111-130
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• 2010

An uncertainty assessment for precipitation datasets simulated by Atmosphere-Ocean Coupled General Circulation Model (AOGCM) is conducted to provide reliable climate scenario over East Asia. Most of results overestimate precipitation compared to the observational data (wet bias) in spring-fall-winter, while they underestimate precipitation (dry bias) in summer in East Asia. Higher spatial resolution model shows better performances in simulation of precipitation. To assess the uncertainty of spatiotemporal precipitation in East Asia, the cyclostationary empirical orthogonal function (CSEOF) analysis is applied. An annual cycle of precipitation obtained from the CSEOF analysis accounts for the biggest variability in its total variability. A comparison between annual cycles of observed and modeled precipitation anomalies shows distinct differences: 1) positive precipitation anomalies of the multi-model ensemble (MME) for 20 models (thereafter MME20) in summer locate toward the north compared to the observational data so that it cannot explain summer monsoon rainfalls across Korea and Japan. 2) The onset of summer monsoon in MME20 in Korean peninsula starts earlier than observed one. These differences show the uncertainty of modeled precipitation. Also the comparison provides the criteria of annual cycle and correlation between modeled and observational data which helps to select best models and generate a new MME, which is better than the MME20. The spatiotemporal deviation of precipitation is significantly associated with lower-level circulations. In particular, lower-level moisture transports from the warm pool of the western Pacific and corresponding moisture convergence significantly are strongly associated with summer rainfalls. These lower-level circulations physically consistent with precipitation give insight into description of the reason in the monsoon of East Asia why behaviors of individually modeled precipitation differ from that of observation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.242-242
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• 2006

Increasingly complex tasks are performed by computers or cellular phone, requiring more and more memory capacity as well as faster and faster processing speeds. This leads to a constant need to develop more highly integrated circuit systems. Therefore, there have been numerous studies by many engineers investigating circuit patterning. In particular, PCB including module/package substrates such as FCB (Flip Chip Board) has been developed toward being low profile, low power and multi-functionalized due to the demands on miniaturization, increasing functional density of the boards and higher performances of the electric devices. Imprint lithography have received significant attention due to an alternative technology for photolithography on such devices. The imprint technique. is one of promising candidates, especially due to the fact that the expected resolution limits are far beyond the requirements of the PCB industry in the near future. For applying imprint lithography to FCB, it is very important to control thermal properties and mechanical properties of dielectric materials. These properties are very dependent on epoxy resin, curing agent, accelerator, filler and curing degree(%) of dielectric materials. In this work, the epoxy composites filled with silica fillers and cured with various accelerators having various curing degree(%) were prepared. The characterization of the thermal and mechanical properties wasperformed by thermal mechanical analysis (TMA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), rheometer, an universal test machine (UTM).

• Journal of the Korean Society for Computer Game
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• v.31 no.4
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• pp.37-50
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• 2018

This study multi-dimensionally analyzes "Indie Game: The Movie", The game documentary film published in June, 2012. As game industry increases, game-related documentary films are also being produced. Previous game documentary films usually focus on the success of popular game or game users and deal with the reason of success. However, "Indie Game: The Movie" centers on Indie game developers who are not from famous and huge companies. Due to the development of the game engine, these days, Indie games become a new trend that game developers are able to develop their own game freely. Then, this study has a purpose to study the life of Indie game developers and explore how and why they want to make their own game. More specifically, this study analyzes "Indie Game: The Movie" by 1) Story 2) Conflict and Resolution 3) Form 4) Sequence. As a result, it concludes that "Indie Game: The Movie" has interview section mainly and represents that Indie game developers want to develop their own games due to their ego and identity. In other words, throughout the analysis of the documentary film, it explores the reality that Indie Game developers face and many features of Indie Game in the game industry.

• Korean Journal of Remote Sensing
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• v.40 no.1
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• pp.93-101
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• 2024

Accurate field crop classification is essential for various agricultural applications, yet existing methods face challenges due to diverse crop types and complex field conditions. This study aimed to address these issues by combining support vector machine (SVM) models with multi-seasonal unmanned aerial vehicle (UAV) images, texture information extracted from Gray Level Co-occurrence Matrix (GLCM), and RGB spectral data. Twelve high-resolution UAV image captures spanned March-October 2021, while field surveys on three dates provided ground truth data. We focused on data from August (-A), September (-S), and October (-O) images and trained four support vector classifier (SVC) models (SVC-A, SVC-S, SVC-O, SVC-AS) using visual bands and eight GLCM features. Farm maps provided by the Ministry of Agriculture, Food and Rural Affairs proved efficient for open-field crop identification and served as a reference for accuracy comparison. Our analysis showcased the significant impact of hyperparameter tuning (C and gamma) on SVM model performance, requiring careful optimization for each scenario. Importantly, we identified models exhibiting distinct high-accuracy zones, with SVC-O trained on October data achieving the highest overall and individual crop classification accuracy. This success likely stems from its ability to capture distinct texture information from mature crops.Incorporating GLCM features proved highly effective for all models,significantly boosting classification accuracy.Among these features, homogeneity, entropy, and correlation consistently demonstrated the most impactful contribution. However, balancing accuracy with computational efficiency and feature selection remains crucial for practical application. Performance analysis revealed that SVC-O achieved exceptional results in overall and individual crop classification, while soybeans and rice were consistently classified well by all models. Challenges were encountered with cabbage due to its early growth stage and low field cover density. The study demonstrates the potential of utilizing farm maps and GLCM features in conjunction with SVM models for accurate field crop classification. Careful parameter tuning and model selection based on specific scenarios are key for optimizing performance in real-world applications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.336-339
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• 2011

In the RTLS(Real Time Location Based System), in case of existing a number of moving target, extremely complecated data flow is can be occurred. In the network where single gateway exists, various data which was collected from sensor node is transmitted along the simple route as time goes by. In case of multi-gateway configuration, the collected data is transmitted through diverse routes rather than simple route. This kind of data causes jams on nodes and this brings down the performance of the network. Different from existing studies, in this thesis, MAC (Media Access Control) protocol which minimizes data collision between nodes and guarantees QoS(Quality of Service) is suggested, in order to communicate efficiently in multi-gateway underwater sensor network environment. In the suggested protocol, source node which wants to transmit data makes a channel reservation to a number of destination node using a RTS packet. Source node reserves a channel without collision, by scheduling CTS response time using expected delay information from neighbor nodes. Once the reservation is made, source node transmit data packet without collision. This protocol analyzes/estimates the performance compared to a method provided from existing studies via simulation. As a results of the analysis, it was comfirmed that the suggested method has better performance, such as efficiency and delay.

• The Korean Journal of Gastroenterology
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• v.72 no.6
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• pp.286-294
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• 2018

Background/Aims: The predictive factors of functional dyspepsia (FD) remain controversial. Therefore, we sought to investigate symptom responses in FD patients after Helicobacter pylori (H. pylori) eradication and used predictive factor analysis to identify significant factors of FD resolution at one-year after commencing eradication therapy. Methods: This prospective, multi-center clinical trial was performed on 65 FD patients that met Rome III criteria and had H. pylori infection. Symptom responses and factors that predicted poor response were determined by analysis one year after commencing H. pylori eradication therapy. Results: A total of 63 patients completed the one-year follow-up. When an eradication success group (n=60) and an eradication failure group (n=3) were compared with respect to FD response rate at one year, results were as follows; complete response 73.3% and 0.0%, satisfactory response 1.7% and 0.0%, partial response 10.0% and 33.3%, and refractory response 15.0% and 66.7%, respectively (p=0.013). Univariate analysis showed persistent H. pylori infection (p=0.021), female gender (p=0.025), and medication for FD during the study period (p=0.013) were associated with poor FD response at one year. However, age, smoking, alcohol consumption, and underlying disease were not found to affect response. Finally, multivariate analysis showed that female gender (OR, 4.70; 95% CI, 1.17-18.88) was the sole independent risk factor of poor FD response at one year after commencing H. pylori eradication therapy. Conclusions: Female gender was found to predict poor response in FD patients despite H. pylori eradication. Furthermore, successful H. pylori eradication appears to be associated with FD improvement, but the number of non-eradicated patients was too small to conclude.

• Journal of the Korean earth science society
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• v.44 no.6
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• pp.643-654
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• 2023

The West Philippine Basin, an oceanic basin half the size of the Philippine Sea Plate, lies in the western part of the plate and south of the Korean Peninsula on the Eurasian Plate. It subducts beneath the Eurasian Plate and the Philippine Islands bordering the Ryukyu Trench and the Philippine Trench with 25-50% of this basin already consumed. However, the history of the opening of the basin's southern region has been a topic of debate. The non-transform discontinuity formed during the seafloor spreading is similar to the transform fault boundaries normally perpendicular to mid-ocean ridge axes; however, it was created irregularly due to ridge propagations caused by variations of mantle convection attributable to magma supply changes. By analyzing high-resolution multi-beam echo-sounding data, we confirmed that the non-transform discontinuity due to the propagating rift evolved in the entire basin and that the abyssal hill strike direction changed from E-W to NNW-SSE from the fossil spreading center. In the early stage of basin extension, the Amami-Sankaku Basin was rotated 90 degrees clockwise from its current orientation, and it bordered the Palau Basin along the Mindanao Fracture Zone. The Amami-Sankaku Basin separated from the Palau Basin while the spreading of the West Philippine Basin began with a counter-clockwise rotation. This indicates that the non-transform discontinuities formed by a sudden change in magma supply due to the drift of the Philippine Sea Plate and simultaneously with the rapid changes in the spreading direction from ENE-WSW to N-S. The Palau Basin was considered to be the sub-south of the West Philippine Basin, but recent studies have shown that it extends into an independent system. Evidence from sediment layers and crustal thickness hints at the possibility of its existence before the West Philippine Basin opened, although its evolution continues to be debated. We performed a combined analysis using high-resolution multi-beam bathymetry and satellite gravity data to uncover new insights into the evolution of the West Philippine Basin. This information illuminates the complex plate interactions and provides a crucial contribution toward understanding the opening history of the basin and the Philippine Sea Plate.

• Korean Journal of Remote Sensing
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• v.33 no.6_2
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• pp.1139-1149
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• 2017

Measuring tree's volume is very important input data of various environmental analysis modeling However, It's difficult to use economical and equipment to measure a fragmented small green space in the city. In addition, Trees are sensitive to seasons, so we need new and easier equipment and quantification methods for measuring trees than lidar for high frequency monitoring. In particular, the tree's size in a city affect management costs, ecosystem services, safety, and so need to be managed and informed on the individual tree-based. In this study, we aim to acquire image data with UAV(Unmanned Aerial Vehicle), which can be operated at low cost and frequently, and quickly and easily quantify a single tree using SfM-MVS(Structure from Motion-Multi View Stereo), and we evaluate the impact of reducing number of images on the point density of point clouds generated from SfM-MVS and the quantification of single trees. Also, We used the Watertight model to estimate the volume of a single tree and to shape it into a 3D structure and compare it with the quantification results of 3 different type of 3D models. The results of the analysis show that UAV, SfM-MVS and solid model can quantify and shape a single tree with low cost and high time resolution easily. This study is only for a single tree, Therefore, in order to apply it to a larger scale, it is necessary to follow up research to develop it, such as convergence with various spatial information data, improvement of quantification technique and flight plan for enlarging green space.