• Economic and Environmental Geology
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• v.54 no.2
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• pp.299-308
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• 2021

Fe(II) released from mining activities is precipitated as various Fe(III)-oxyhydroxides when exposed to an oxidizing environment including mine drainage. Ferrihydrite, one of the representative precipitated Fe(III) minerals, is easy to adsorb heavy metals and other pollutants due to the large specific surface area caused by very low crystallinity. Ferrihydrite is transformed to thermodynamically more stable goethite in the natural environment. Hence, information on the transformation of ferrihydrite to goethite and the related mobility of heavy metals in the acid mine drainage is important to predict the behaviors of those elements during ferrihydrite to goethite transition. The behaviors of heavy metals during the transformation of ferrihydrite to goethite were investigated for core samples collected from an AMD treatment system in the Heungjin-Taemaek coal mine by using X-ray diffraction (XRD), chemical analysis, and statistical analysis. XRD results showed that ferrihydrite gradually transformed to goethite from the top to the bottom of the core samples. Chemical analysis showed that the relative concentration of As was significantly high in the core samples compared with that in the drainage, indicating that As was likely to be adsorbed strongly on or coprecipitated with iron oxyhydroxide. Correlation analysis also indicated that As can be easily removed from mine drainage during iron mineral precipitation due to its high affinity to Fe. The concentration ratio of As, Cd, Co, Ni, and Zn to Fe generally decreased with depth in the core samples, suggesting that mineral transformation can increase those concentrations in the drainage. In contrast, the concentration ratio of Cr to Fe increased with depth, which can be explained by the chemical bond of iron oxide and chromate, and surface charge of ferrihydrite and goethite.

• Journal of Korean Historical Folklife
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• no.33
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• pp.31-72
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• 2010

At first, I extract materials on folk religion from four encyclopedic literatures of late Chosun dynasty-Lee, Ji-Bong-Ryu-Seol(『芝峯類說』) by Soo-Kwang(李晬光), San-Lim-Kyung-Jae(『山林經濟』) by Hong, Man-Sun(洪萬選), Sung-Ho-Sa-Seol(『星湖僿說』) by Lee-Ik(李瀷), O-Ju-Yeon-Moon-Jang-Jun-San-Go(『五洲衍文長箋散稿』) by Lee, Kyu-Kyung(李圭景), and present these materials by tables. Second, I examined the contents and characters of these materials on folk religion. The conclusions from this research are as follows. ① There are common features and points of difference between these four encyclopedic literatures. One of common features are that all these four are encyclopedic works, but San-Lim-Kyung-Jae is more practical than another three. ② These encyclopedic literatures regard folk religion as a negative culture, because these literatures based on Confucianism. But they did not deny miraculous virtues of folk religion. ③ These encyclopedic literatures give us many informations on gods and spirits of Korean folk religion, i.e. city gods(城隍神)·Yup-Sin(업신)·spirits of disease, god Kim-Bu(金傅大王神)·god Jung-Duk-Yang(鄭得揚)·god of King Kuan-u(關王神)·god Bu-keun(付根神) etc. So I review these gods and spirits referenced in encyclopedic literatures. ④ These encyclopedic literatures show much interest in ghost in common. The reason of interest is that authors of these encyclopedic literatures are all scholars of Sung Confucianism and Sung Confucian was concern about ghost. The Sung Confucianism denied the ghost as personal being whom Korean folk religion regards to a kind of spirits. Instead of beliefs in ghost of folk religion, they insist on the ghost as Ki(氣), a kind of cosmic principle. But these encyclopedic literatures acknowledge some parts of folk religion's beliefs in ghost, because they admit the miraculous virtues of these parts. ⑤ There are many items on divination in these encyclopedic literatures. But they show dual attitude on divinations. The one is negative attitude to divinations on individual destiny and the other one is positive attitude to divinations on agriculture. ⑥ There are also many items on witchcrafts in these encyclopedic literatures. Through these items, I assumed pervasiveness of beliefs on witchcraft at that time. ⑦ Shamans, as religious specialist, are stand on a central position of Korean folk religion. So it is a matter of course that these encyclopedic literatures concerned on Korean shaman. As Confucians, authors of these encyclopedic literatures did not regards shamans as positive one. But they did not deny miraculous virtues of shamans. In spite of these encyclopedic literatures have negative view points to, and include false informations Korean folk religion, I would like to emphasis on importance of these encyclopedic literatures to understand Korean folk religions, especially Korean folk religions of late Yi Dynasty.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.8
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• pp.367-376
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• 2007

In this paper, we introduce an application-specific and adaptive power management technique for portable systems that support dynamic voltage scaling (DVS). We exploit both the idle time of multitasking systems running soft real-time tasks as well as memory- or CPU-bound code regions. Detailed power and execution time profiles guide an adaptive power manager (APM) that is linked to the operating system. A post-pass optimizer marks candidate regions for DVS by inserting calls to the APM. At runtime, the APM monitors the CPU's performance counters to dynamically determine the affinity of the each marked region. for each region, the APM computes the optimal voltage and frequency setting in terms of energy consumption and switches the CPU to that setting during the execution of the region. Idle time is exploited by monitoring system idle time and switching to the energy-wise most economical setting without prolonging execution. We show that our method is most effective for periodic workloads such as video or audio decoding. We have implemented our method in a multitasking operating system (Microsoft Windows CE) running on an Intel XScale-processor. We achieved up to 9% of total system power savings over the standard power management policy that puts the CPU in a low Power mode during idle periods.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.111-124
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• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.1-10
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• 2012

Many statistical methods have been adapted for terminology recognition to improve its accuracy. However, since previous studies have been carried out in a single core or a single machine, they have difficulties in real-time analysing explosively increasing documents. In this study, the task where bottlenecks occur in the process of terminology recognition is classified into linguistic processing in the process of 'candidate terminology extraction' and collection of statistical information in the process of 'terminology weight assignment'. A terminology recognition system is implemented and experimented to address each task by means of the distributed parallel processing-based MapReduce. The experiments were performed in two ways; the first experiment result revealed that distributed parallel processing by means of 12 nodes improves processing speed by 11.27 times as compared to the case of using a single machine and the second experiment was carried out on 1) default environment, 2) multiple reducers, 3) combiner, and 4) the combination of 2)and 3), and the use of 3) showed the best performance. Our terminology recognition system contributes to speed up knowledge extraction of large scale science and technology documents.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.71-78
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• 2020

In the case of power generation using renewable energy, power production may not be smooth due to the influence of the weather. The energy storage system (ESS) is used to increase the efficiency of solar and wind power generation. ESS has been continuously fired due to a lack of battery protection systems, operation management, and control system, or careless installation, leading to very big casualties and economic losses. ESS stability and battery protection system operation management technology is indispensable. In this paper, we present a battery level calculation algorithm and a failure prediction algorithm for ESS optimization and stable operation. The proposed algorithm calculates the correct battery level by accumulating the current amount in real-time when the battery is charged and discharged, and calculates the battery failure by using the voltage imbalance between battery cells. The proposed algorithms can predict the exact battery level and failure required to operate the ESS optimally. Therefore, accurate status information on ESS battery can be measured and reliably monitored to prevent large accidents.

• Journal of IKEEE
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• v.13 no.4
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• pp.116-124
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• 2009

Recently the CPU performance of modem chipsets or multimedia processors of mobile phone is as high as notebook PC. That is why mobile phone has been emerged as a leading ICON on the convergence of consumer electronics. The various applications of mobile phone such as DMB, digital camera, video telephony and internet full browsing are servicing to consumers. To meet all the demands the image quality has been increasingly important. Mobile phone is a portable device which is widely using in both the indoor and outside environments, so it is needed to be overcome to deteriorate image quality depending on environmental light source. Furthermore touch window is popular on the mobile display panel and it makes contrast loss because of low transmittance of ITO film. This paper presents the image enhancement algorithm to be embedded on image enhancement SoC. In contrast enhancement, we propose Clipped histogram stretching method to make it adaptive with the input images, while S-shape curve and gain/offset method for the static application And CIELCh color space is used to sunlight readability enhancement by controlling the lightness and chroma components which is depended on the sensing value of light sensor. Finally the performance of proposed algorithm is evaluated by using histogram, RGB pixel distribution, entropy and dynamic range of resultant images. We expect that the proposed algorithm is suitable for image enhancement of embedded SoC system which is applicable for the small-sized mobile display.

• Management & Information Systems Review
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• v.34 no.5
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• pp.251-276
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• 2015

This study is to review the attitude of consumers on the crisis response strategy (defensive vs. receptive) that the company implements in crisis situations. Also, the interaction between the crisis response strategy that the company implements and the crisis type of companies (corporate ability vs corporate social responsibility) was discussed. In addition, the interaction between the messages (abstract vs. concrete) of public interest associated marketing implemented prior to crisis situations and the crisis response strategy implemented after crisis situations was discussed. And these results were reviewed to see if the same result can come out after controlling the involvement on consumer's public interest associated marketing as a covariate. The main results of this study are as follows. First, regarding the crisis response strategy, in the company's crisis response strategy, the receptive attitude was more favorable for the consumer's attitude than the defensive attitude. Second, it was seen that there is a significant interaction between the crisis response strategy of companies and the crisis type of companies. Third, it was seen that the crisis response strategy of companies has a significant interaction with the message type of public interest associated marketing. Lastly, the involvement showed a significant effect as a covariate and the interaction between the crisis response strategy of companies, the crisis type of company and the message type of public interest associated marketing can be confirmed even after controlling the involvement. In the conclusion of the study, the direction on implications, limitations and future.

• Journal of Korea Water Resources Association
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• v.50 no.1
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• pp.29-35
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• 2017

A vehicle rainfall sensor is made to control the operating speed of wipers depending on rainfall. Therefore this is the apparatus to determine the velocity phase of the wipers roughly based on the amount of rainfall. However, the technology which can judge the size of rainfall amount besides determining speed level of the wipers is developing according to the development of the function of rainfall sensor due to the development of technology. In this study, a rainfall measurement by using light scattering by precipitation particles was used. This measurement is to use light signal reflection from front glass and the bigger particle is the less detection of light by light scattering. The detection area of the rainfall sensor and detection channel were extended sizes to increase the accuracy of the rainfall. Also the W-S-R relational expression was developed by using a relationship between the specific precipitation (R) and the amount of sensor detection (S) when there is speed change of the wipers (W) and an indoor rainfall apparatus was used to convert sensing signal to rainfall. The signal system of vehicle rainfall sensor can be converted to the actual rainfall amount by using this formula and if this is provided to users then the vehicle observation network can produce higher-resolution than actual observation network can be produced.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.111-133
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• 2015

This study was carried out to survey the vascular plants of Baekdudaegan Arboretum area. The results are as follows. The numbers of flora in this study area were summarized as 655 taxa including 95 families, 332 genera, 567 species, 5 subspecies, 72 varieties and 11 formas. The rare plants were 17 taxa including Parasenecio firmus, Rhododendron micranthum, Iris odaesanensis, Lysimachia coreana and so forth. The Korean endemic plants were 16 taxa including Weigela subsessilis, Heloniopsis koreana, Salix koriyanagi, Vicia chosenensis and so forth. Plants Adaptable to Climate Change were Northern plants 18 species, Southern plants 2 species, endemic plants 10 species. The naturalized plants were 44 taxa and ratios of naturalized index and urbanization index were estimated Core area 10.2% and 4.9%, Mt. Munsu 4.9% and 2.3% and Mt. Okseok 5.5% and 2.6%. The floristic regional indicator plants found in this area were 3taxa(2.5%) of grade V, 12taxa(11.0%) of grade IV, 22taxa(20.2%) of grade III, 35taxa(32.1%) of grade II. In life forms, hemicryptophytes were The most dominant. Next was a Therophytes. In addition, 492 taxa were categorized by usage into 8 groups, as follows: Edible 239taxa(36.5%), Fiber 10taxa(1.5%), Industrial 1taxon(0.2%), Miscellaneous 183taxa(27.9%), Ornamental 65taxa(9.9%), Pasturing 259taxa(39.5%), Siscellaneousg 14taxa(2.1%) and Timer 21taxa(3.2%).