• Geophysics and Geophysical Exploration
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• v.21 no.2
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• pp.67-81
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• 2018

We acquired the magnetic and bathymetry data around the TA (Tofua Arc) 22 seamount in the Lau Basin for finding submarine hydrothermal deposits. From the data, we estimated the magnetic characteristics in the study area. The bathymetry shows that TA 22 seamount consists of the western and eastern summits. Each summit exhibits a caldera. The western caldera is smaller, but deeper than the eastern caldera. The slope gradients of the TA 22 are steeper around ~1000 m depth range and relatively gentle at the summit areas with the small difference of two calderas. The magnetic properties of TA 22 seamount present high anomalies at the summit and the vicinity of the caldera. Low magnetization zones appear over the outer flanks and center of the calderas. These magnetic patterns are similar to the previous studies which had represented high anomalies and low magnetization zones inside of the summit area or on the flank of the outside of the summit area. The results of the 2D magnetic forward modeling with seismic profiles show about 20 nT of RMSEs (root mean square error) between the modeled and observed values. The low RMSEs proposes a good correlation between the modeled 2D structure and the geophysical observation in this study area. Based on the modeling and magnetization distribution, hydrothermal deposits are predicted to be located at the inner area of the calderas or at small mounds around caldera rims.

• The Journal of Society for e-Business Studies
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• v.25 no.4
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• pp.143-154
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• 2020

With the increasing trend of making manufacturing system intelligent and autonomous, the introduction of robot-assist automation, like machine tending system for automated operation of CNC machine tools, is being actively carried out at many industrial sites. Most important part of this intelligent system to install machine tending system, is interface programming between the CNC machine tools and the industrial robot. Despite this importance, however, the machine tending system has many setup problems. it is necessary for difficult re-program of both controllers whenever a new CNC machine tool or robot is introduced. And, the helps of external engineers is required even though trivial changes due to the complex structure of the machine tending system. Authors of this paper introduces the integrated system of the interface between heterogeneous CNC machine tools and industrial robots. In addition, the digital twin implemented inside the machine tool controller enable shop-floor operators to change the interface programming easily. To implement this system, an integrated development environment for 1) an intelligent HMI platform that provide standardized interfaces to heterogeneous CNC machine tools and 2) a robot platform developing application software of various robots, was established. For easy un-tact environment, this paper explain the development of 3) a game-engine based web program of controlling and monitoring machine tending system remotely.

• Food Science and Preservation
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• v.22 no.6
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• pp.823-830
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• 2015

Physicochemical properties of five commercial rice products were investigated in order to select the appropriate rice varieties for the preparation of frozen fried rice. Among the evaluated rice varieties, Onnuri (16.06%) had the highest amylose content, while Beakjinju (11.83%) had the lowest. The water absorption index ranged from 1.45 to 1.65 g/g. Regarding the Hunter's color values, the L and a values of all rice varieties decreased while the b value increased with freezing-storage following the cooking process. The initial pasting temperature showed no significant differences among the five rice varieties. The highest viscosity (peak, trough, and final) and setback were found in the Sindongjin, while the lowest breakdown was found in the Baekjinju variety. Hardness, chewiness, and cohesiveness of all five cooked rice varieties decreased while their adhesiveness increased after freezing-storage. Under electron microscopy scanning, pores were observed inside the tissue of frozen cooked rices manufactured from Baekjinju and Hopum varieties, while substantially smooth tissue structure was observed in Sindognjin, Onnuri, and Ilmi rice varieties.

• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.72-80
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• 2014

This study proposed a wind power generation system utilizing outdoor air on the rooftop and indoor ventilation, which would increase according to the building height, as a way to help to save energy consumption in a building by using wind power energy of the new renewable energy sources. The study measured the distribution of air currents and power generation according to the usage factor of exhaust pipes in the kitchen and bathroom and identified the elements to consider when applying a wind power generation system to buildings in order to use outdoor air on the rooftop increasing according to the height and the indoor ventilation produced in the facility vertical shafts inside the buildings by installing a wind power generation system on the rooftop. (1) The study measured the ventilation velocity of the kitchen hood and bathroom ventilation fan by changing the zone areas by the households according to the usage factor of [${\alpha}$]=33~100%. As a result, the kitchen ventilation pipe generated the ventilation wind of 3.0m/s or more at the usage factor of [${\alpha}$] 66% or higher, and the bathroom ventilation pipe generated ventilation velocity lower than 3.0m/s, the blade velocity of the wind power generator, even after the usage factor rose to [${\alpha}$]=100%. (2) As the old bathroom ventilation pipe generated the ventilation velocity of 3.0m/s, the blade velocity of the wind power generator, even with the rising usage factor [${\alpha}$], the application of an outdoor air induction module increased the ventilation velocity by 2.9m/s at the usage factor of [${\alpha}$]=33%, 3.8m/s at the usage factor of [${\alpha}$]=66%, and 3.6m/s at the usage factor of [${\alpha}$]=100%. Thus the ventilation velocity of 3.0m/s, the blade velocity of the wind power generator, or higher was secured. (3) The findings prove that the applicability of a wind power generation system using outdoor air on the rooftop and indoor ventilation is excellent, which raises a need for various efforts to increase the possibility of its commercialization such as securing its structural stability according to momentary gusts on the rooftop and typhoons in summer and making the structure light to react to the wind directions of outdoor air on the rooftop according to the seasons.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.3
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• pp.224-234
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• 2005

As the network-related technology develops the number of both Internet users and the usage are explosively increasing. The networking traffic is increasing in the campus as the networking system inside universities, following the trend, adds more nodes and various networking services. Nonetheless, the quality of services for users has been degraded. Accordingly, core problems, which can cause troubles for network management, design and expansion of the network, and the cost policy, has appeared. To effectively cope with the problems with analyses a great number of technicians, tools, and budget are needed. However, it is not possible for mid and small-sized colleges to spend such a high expenditure for professional consulting. To reduce the cost and investment creating the optimized environment, the analyses on the replacement of the tools, changing the network structure, and performance analysis about capacity planning of networking is necessary. For this reason, in this paper, framework-based performance management tools are used for all steps that are related to the subject of the analysis for the network management. As the major research method, the current data in detailed categories are collected, processed, and analyzed to provide the solution for the problems. As a result we could manage the network, server, and application more systematically and react efficiently to errors and degrading of performance that affect the networking tasks. Also, with the scientific and organized analyses the overall efficiency is upgraded by optimizing the cost for managing the operation of entire system.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.4 s.316
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• pp.42-47
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• 2007

To reduce the chattering errors of reed switch sensors in the automatic remote measurement of water meter a reed switch sensor was analyzed and improved. The operation of reed switch sensors can be described as a mechanical contact switch by approximation of permanent magnet piece to generate an electrical pulse. The reed switch sensors are used mostly in measurement application to detect the rotational or translational displacement. To apply for water flow measurement devices, the reed switch sensors should keep high reliability. They are applied for the electronic digital type of water flow meters. The reed switch sensor is just mounted simply on the conventional mechanical type flow meter. A small magnet is attached on a pointer of the water meter counter rotor. Inside the reed sensor two steel leaf springs make mechanical contact and apart repeatedly as rotation of flow meter counter. The counting electrical contact pulses can be converted as the water flow amount. The MCU sends the digital flow rate data to the server using the wireless communication network. But the digital data is occurred difference or won by chattering noise. The reed switch sensor contains chattering error by it self at the force equivalent position. The vibrations such as passing vehicle near to the switch sensor installed location causes chattering. In order to reduce chattering error, most system uses just software methods, for example using filter algorithm and also statistical calibration methods. The chattering errors were reduced by changing leaf spring structure using mechanical characteristics.

• Journal of the Korea Computer Graphics Society
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• v.16 no.4
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• pp.25-33
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• 2010

With the popularization of digital photography, people are now capturing and storing far more photos than ever before. However, the enormous number of photos often discourages the users to identify desired photos. In this paper, we present a novel method for fast and intuitive browsing through large collections of geo-referenced photographs. Given a set of photos, we construct a hierarchical structure of clusters such that each cluster includes a set of spatially adjacent photos and its sub-clusters divide the photo set disjointly. For each cluster, we pre-compute its convex hull and the corresponding polygon area. At run-time, this pre-computed data allows us to efficiently visualize only a fraction of the clusters that are inside the current view and have easily recognizable sizes with respect to the current zoom level. Each cluster is displayed as a single polygon representing its convex hull instead of every photo location included in the cluster. The users can quickly transfer from clusters to clusters by simply selecting any interesting clusters. Our system automatically pans and zooms the view until the currently selected cluster fits precisely into the view with a moderate size. Our user study demonstrates that these new visualization and interaction techniques can significantly improve the capability of navigating over large collections of geo-referenced photos.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.4
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• pp.743-755
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• 2018

Tunnel is a semi-closed structure similar to underground space where the smoke generated from fire fills the space fast while escaping from the space slow. Because of such characteristics, when the fire breaks out by traffic accident, the vehicles are jammed making it difficult for the people to evacuate from the scene as well as for the fire engine to gain access to the scene. For such reasons, tunnels are globally categorized into some disaster classes for differentiated facilities and operation approaches. In Korea, less than a 1 km-long tunnel accounts for 80.0% and such a short tunnel which is categorized into Class III is not required to have smoke control system. In this study, a full-scale fire test was conducted in a bid to apply air curtain system using heat-resistant sirocco fan to a less than 1 km-long tunnel. To that end, heat resistance test to verify the normal operation at $250^{\circ}C$ for 60 minutes was conducted. Consequently, despite of rapid rising-temperature and increasing-carbon dioxide inside the air curtain (direction of fire in tunnel), initial condition was found to have been sustained outside the air curtain (opposite direction of fire in tunnel).

• Journal of The Korean Association of Information Education
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• v.8 no.3
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• pp.293-303
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• 2004

To follow in change and the development which circumference environment of education are quick even from scene of education students form the structure of knowledge themselves, the place where own lead studying of personal small group studying is emphasized, here upon specialist learning activity there is a wild possibility in the model which is suitable. But, studying of the learning paper was most center mainly the specialist learning activity of existing, it solves a learning problem at unit hour to, the hour was too insufficient to solve and it became plentifully at block time. But, this is to the curriculum operation and or the schedule operation it is when trying to consider the intensive degree of learning the elementary student, a problem point there is. It grasps the strong point and a weak point of specialist learning activity model of existing from the research which consequently, it sees and it applies more efficiently from web base study to establish the instructional strategy for, it composed the modules which strengthen the interaction of learning subject for. Also, unit macro learning and block time learning in order to do to become accomplished at web with studying problem, it will be able to solve inside unit hour in order, specialist teaching-learning system based on the web. It developed, after applied in the electrification S elementary school 5 grades which will reach the result, it analyzed.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.896-907
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• 2016

The habitat characteristics of Aconitum austrokoreense Koidz. were investigated to provide basic data for conservation and restoration. The altitude ranged from 260m to 728m with inclinations of $4-39^{\circ}$. As a result of vegetation survey within natural populations, a total of 147 taxa were identified inside 20 quadrates in 7 natural habitats. The importance value of Aconitum austrokoreense was 23.0% based on the coverage and frequency of the herbaceous layer and sat is more dominant. Species diversity was 1.23, and dominace and evenness were found to be 0.22 and 0.77, respectively. The soil type were silty loam (four sites), sandy loam (two sites) and loam (one site). The average field organic matter was 7.83% and the total nitrogen and pH were 0.35, and 5.69. Correlation analysis between environmental factors and population characteristic showed the correlations between chlorophyll content and slope, flowering rate and soil humidity. Conservation on habitats conditions is important for stable maintenance the flora and the surrounding area including habitats has to be designated a protection area for habitats conservation.