• Journal of KIISE:Databases
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• v.37 no.4
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• pp.177-184
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• 2010

In these day, many data including sensor, delivery, credit and stock data are generated continuously in massive quantity. It is difficult to learn from these data because they are large in volume and changing fast in their concepts. To handle these problems, learning methods based in sliding window methods over time have been used. But these approaches have a problem of rebuilding models every time new data arrive, which requires a lot of time and cost. Therefore we need very simple incremental learning methods. Bayesian method is an example of these methods but it has a disadvantage which it requries the prior knowledge(probabiltiy) of data. In this study, we propose a learning method based on attribute values. In the proposed method, even though we don't know the prior knowledge(probability) of data, we can apply our new method to data. The main concept of this method is that each attribute value is regarded as an expert learner, summing up the expert learners lead to better results. Experimental results show our learning method learns from data very fast and performs well when compared to current learning methods(decision tree and bayesian).

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.59-67
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• 1987

The pot experiment was conducted using soils with varying contents of available phosphorus to select the reasonable method for determination of the available phosphorus content in soils for Nak-Dong rice cultivation. On a basis of the responses to the phosphorus tertilizer applied, the linear correlation coefficients by Bray No.1, Bray No.2, Lancaster, North Carolina and Olsen methods were 0.887, 0.868, 0.879, 0.952 and 0.911 for Nak-Dong rice yield, respectively. Of the methods tested, North Carolina method was the most suitable for determining, the phosphorus content in soils for Nak-Dong rice. The phosphorus application promoted the growth of Nak-Dong rice in pots for culm, tiller number, available stem and grain number per ear. Based on this experiment it could be presumed that the recommanded quantity of phosphorus fertilizer should attain to 5kg per 10a to promote the growth of Nak-Dong rice in A-soil and 10kg per 10a in B -, C - and D-soil. The results from the pot experiment will be somewhat different from those from the field experiment. Therefore, field experiment should be carried out for further information.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.1-1
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• 2016

Many of the world's large ecosystems are severely stressed due to population growth, water quality and quantity problems, vulnerability to flood and drought, and the loss of native species and cultural resources. Consequences of climate change further increase uncertainties about the future. These major societal challenges must be addressed through innovations in governance, policy, and ways of implementing management strategies. Science and engineering play a critical role in helping define possible alternative futures that could be achieved and the possible consequences to economic development, quality of life, and sustainability of ecosystem services. Science has advanced rapidly during the past decade with the emergence of science communities coalescing around 'Grand Challenges' and the maturation of how these communities function has resulted in large interdisciplinary research networks. An example is the River Experiment Center of KICT that engages researchers from throughout Korea and the world. This trend has been complemented by major advances in sensor technologies and data synthesis to accelerate knowledge discovery. These factors combine to allow scientific debate to occur in a more open and transparent manner. The availability of information and improved communication of scientific and engineering issues is raising the level of dialogue at the science-policy interface. However, severe challenges persist since scientific discovery does not occur on the same timeframe as management actions, policy decisions or at the pace sometimes expected by elected officials. Common challenges include the need to make decisions in the face of considerable uncertainty, ensuring research results are actionable and preventing science being used by special interests to delay or obsfucate decisions. These challenges are explored in the context of examples from the United States, including the California Bay-Delta system. California transfers water from the wetter northern part of the state to the drier southern part of the state through the Central Valley Project since 1940 and this was supplemented by the State Water Project in 1973. The scale of these activities is remarkable: approximately two thirds of the population of Californians rely on water from the Delta, these waters also irrigate up to 45% of the fruits & vegetables produced in the US, and about 80% of California's commercial fishery species live in or migrate through the Bay-Delta. This Delta region is a global hotspot for biodiversity that provides habitat for over 700 species, but is also a hotspot for the loss of biodiversity with more than 25 species currently listed by the Endangered Species Act. Understanding the decline of the fragile ecosystem of the Bay-Delta system and the potential consequences to economic growth if water transfers are reduced for the environment, the California State Legislature passed landmark legislation in 2009 (CA Water Code SS 85054) that established "Coequal goals of providing a more reliable water supply for California and protecting, restoring, and enhancing the Delta ecosystem". The legislation also stated that "The coequal goals shall be achieved in a manner that protects and enhances the unique cultural, recreational, natural resource, and agricultural values of the Delta as an evolving place." The challenges of integrating policy, management and scientific research will be described through this and other international examples.

• Journal of Korea Port Economic Association
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• v.25 no.2
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• pp.57-72
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• 2009

The purpose of this paper is to show the empirical measurement way of operation risk evaluation in domestic seaports for overcoming the limitations which the traditional DEA method has by using 13 Korean ports in 2003 for 4 inputs(birthing capacity, cargo handling capacity, number of coastal guard vessel, number o f coastal special guard vessel ) and 5 outputs(Export and Import Quantity, Number of Ship Calls, number of coastal accident, number of coastal crime, number of coastal pollution). Because traditional DEA method has produced the limited set of information, negative DEA mixed with tier, stratification and layering methods should be adopted. The goal of negative DEA is to set up DEA models that will place the poor operating ports on or close to the empirical frontier. The core empirical results of this paper are as follows. First, Donghae ports should benchmark the operation way of Yeasu, Busan, Woolsan ports in terms of the middle and longterm base. Second, 5 ports(ports of Taean, Yeasu, Tongyoung, Busan, Sokcho) which were revealed as the poor operating ports in Negative DEA analysis should benchmark Incheon, Woolsan, Pohan, and Donhae ports. The policy implication to the Korean seaports and planners is that Korean seaports should introduce the new methods like Negative DEA of this paper for predicting the poor operating in the ports.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.2
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• pp.212-221
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• 1999

Tongue examination is the most unique and important diagnostic method of oriental medicine. It reveals patients condition and give some information about direction of therapy and background of disease as well as produces clue of duration of disease changing that grasps it from outside. The aims of this study show that results of tongue examination is related to somewhat special pattern. we study 27 patients(age of means: 63.01 years old, male: 14, female: 13) who come to Wonkwang University Oriental-Medicine Hospital at Chonju with diabetes mellitus or diabetes mellitus complications. Tongue colors of this study result in pale-red 8 cases, pale 6 cases, red 6 cases, crimson 5 cases, blue-green-purple 2 cases and tongue fur of this study result in white-fur 16 cases, yellow-fur 7 cases, black-fur 1 case, none-fur 3 cases. And the condition of tongue fur with grimy and thin result in thin-white-fur 12 cases, white-grimy-fur 4 cases, thin-yellow-fur 5 cases, grimy-yellow-fur 2 cases, black-fur 1 case. Means level of fasting glucose during 7 days was $223.24{\pm}32.l7mg/dl$ and postprandial 2hours was $286.37{\pm}24.54mg/dl$ There were no changes in tongue body and tongue color but changes occur in tongue fur with 9cases in this period. 5 cases of patient make a difference between FBS(fasting blood glucose) and postprandial blood glucose level more than l00mg/dl (2 cases of patient with thin-white-fur gradually turned to slight-yellow-fur. There were no changes in 2 cases of patient with crimson-none-fur and pale-white-fur. 1 case of patient with slimy-yellow-fur turned to black fur.) 11 cases of patient had lesser than $10\%$ hemoglobin $A_lC$ and tongue color of these patient were pale-red 5cases, pale 2 cases, red 2 cases, crimson 2 cases. 16 cases of patient had more than $10\%$ Hemoglobin $A_1C$ and tongue color of these patients were pale-red 3 cases, pale 4 cases, red 4 cases, crimson 3 cases, blue 2 cases. This result shows that quantity of Hemoglobin $A_1C$ make a somewhat role in tongue color. The above results show that tongue color, fur color, condition and change of fur in diabetes mellitus patients is various in pale-red, pale, crimson, none-fur. So it is difficult to give an exact diagnosis on pathology of diabetes mellitus only with tongue examination because there are a little matches between blood glucose level, prevalence-period, short-term blood glucose regulation and tongue and fur colors.

• Journal of the Korean Geotechnical Society
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• v.37 no.10
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• pp.77-87
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• 2021

Several studies have been conducted to analyze, predict, and prevent the risk of ground subsidence occurring in urban areas. Nevertheless, there is insufficient research effort on risk analysis that utilizes the correlation between the density of underground structures (i.e., the spatial quantity of buried objects installed in the ground around the interested area) and the occurrence of ground subsidence. In this paper, a study was conducted to analyze the line density of underground structures using GIS-based spatial information data, and to link this with the recorded ground subsidences. An optimization algorithm was developed to maximize the correlation between the line density of 29 recorded ground subsidences and 6 types of underground structures that occurred between 2010 and 2015 for the analysis area. The concept of normalized line density was also proposed for the analysis. The normalized line density of the analysis area was divided into five grades (Grade 1: lowest, Grade 5: highest). When the optimization algorithm was applied, the case where the normalized line density was Grade 4 or higher at the location of the recorded ground subsidences was about > 80%. It is thought that the density analysis result of underground facilities can be applied to the ground subsidence risk analysis by using the proposed optimization algorithm.

• Journal of the Korean GEO-environmental Society
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• v.22 no.8
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• pp.5-12
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• 2021

Climate change caused by global warming increases the frequency of occurrence of super typhoons and causes various types of sediment disasters such as debris flows in the mountainous area. This study is to evaluate the behavior of debris flow according to the multiplier value of the precipitation characteristics and the quantity of debris flow according to the typhoon category. For the analysis of the debris flow, the finite difference method for time elapse was applied. The larger the typhoon category, the higher the peak value of the flow discharge of debris flow and the faster the arrival time. When the precipitation characteristic multiplier is large, the fluctuation amplitude is high and the bandwidth is wide. When the slope angle was steeper, water discharge increased by 2~2.5 times or more, and the fluctuation of the flow discharge of debris flow increased. All of the velocities of debris flow were included to the class of "Very rapid", and the distribution of the erosion or sedimentation velocity of debris flows showed that the magnitude of erosion increased from the beginning, large-scale erosion occurred, and flowed downstream. The results of this study will provide information for predicting debris flow disasters, structural countermeasures and establishing countermeasures for reinforcing resilience in vulnerable areas.

• Journal of Korea Port Economic Association
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• v.35 no.2
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• pp.109-126
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• 2019

The Panmunjom Declaration adopted by the leaders of South and North Korea on April 27, 2018, has created an environment conducive for peace and cooperation in the Korean Peninsula. In the June of last year, South Korea has joined the Organization for Cooperation between Railways (OSJD). The membership of OSJD has established a solid foundation for restoring a multimodal logistics system that connects the Korean peninsula to Eurasia countries, including China and Russia. In this paper, a questionnaire survey targeting working-level experts was conducted to find the barriers in constructing multimodal logistics that efficiently connect the port-continental railways of the Korean peninsula and the Eurasian nations. Survey items were divided into five categories-border crossing procedures, technology, facilities, operation, and government support. As a result, among the most important problems of international multimodal logistics in Eurasia that need to be solved on priority include improving transshipment facilities, eliminating inspection carried out at every country for transit, simplifying documents for customs clearance, and minimizing the changes in freight rates. In conclusion, for vitalizing the connection between the Korean peninsula and the continental railways, it is necessary to develop a transshipment system to facilitate the changes in tracks at the borders by making a joint effort with the international community. Second, railway and operational systems in South Korea, North Korea, China, and Russia should be standardized. Third, international cooperation among South Korea, North Korea, China, and Russia is essential for simplifying customs clearance at borders, priority departure of domestic cargo, sharing information about the changes in freight rates, and so on. Finally, the government should come up with measures to secure the quantity of cargo required to form block trains, while developing new business models.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.105-118
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• 2019

New manufactural innovation was generated with combination with Do It Yourself(DIY) culture and Information and Communication Technology(ICT). It led people to make their creative idea in real things and share them. This social movement has been called as 'Maker' culture. As maker culture was developed, the places named 'Makerspace' with high-tech equipment and sharing environment have been widely spread and gotten spotlight. Futhermore, makerspaces have been diffused rapidly in Korea; because of its importance for the fourth industrial revolution. However, the operation of makerspaces is not matured as much as its popularity, so problems occurred in operating aspects. The number of related studies is not enough to foster domestic maker culture in Korea. Of that, studies on operation of makerspaces were limited and the quantity of survey sample was insufficient. Therefore, firstly, in this study, operation elements of makerspaces were extracted by literature review. And, survey for examining the extracted elements was conducted to four policy makers and researchers, four makerspace operators and four makers. Final survey was carried out by Importance-Performance Analysis(IPA) method to fifty recipients composed of policy makers and researchers, operators, and makers. In result, importance located above performance in every elements and in-depth interview was followed to understand domestic surroundings and suggest way to invigorate makerspaces in Korea. The suggestion shows as follows. First, online and offline platform for makers should be expanded; second, makerspace should connect private sponsorship with makers or their projects; third, policy direction has to be improved from venturing business to diffusion of maker culture; fourth, basic maker education should be enlarged.

• Journal of the Korean Institute of Gas
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• v.23 no.1
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• pp.27-35
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• 2019

In order to solve the global warming and reduce greenhouse gas emissions, $CO_2$ capture technology was developed by applying oxy-fuel combustion. But there has been such a problem that its economic efficiency is low due to the high price of oxygen gases. ASU is known to be most suitable method to produce large quantity of oxygen, to reduce the oxygen production cost, the efficiency of ASU need to be improved. To improve the efficiency of ASU, exergy analysis can be used. The exergy analysis provides the information of used energy in the process, the location and size of exergy destruction. In this study, the exergy analysis was used for process developing and optimization of large scale ASU. The process simulation of ASU was conducted, the results were used to calculate the exergy. As a result, to reduce the exergy loss in the cold box of ASU, a lower operating pressure process was suggested. It was confirmed the importance of heat leak and heat loss reduction of cold box. Also, the unit process of ASU which requires thermal integration was confirmed.