• Journal of Astronomy and Space Sciences
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• v.34 no.4
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• pp.315-330
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• 2017

Halo coronal mass ejections (CMEs) originating from solar activities give rise to geomagnetic storms when they reach the Earth. Variations in the geomagnetic field during a geomagnetic storm can damage satellites, communication systems, electrical power grids, and power systems, and induce currents. Therefore, automated techniques for detecting and analyzing halo CMEs have been eliciting increasing attention for the monitoring and prediction of the space weather environment. In this study, we developed an algorithm to sense and detect halo CMEs using large angle and spectrometric coronagraph (LASCO) C3 coronagraph images from the solar and heliospheric observatory (SOHO) satellite. In addition, we developed an image processing technique to derive the morphological and dynamical characteristics of halo CMEs, namely, the source location, width, actual CME speed, and arrival time at a 21.5 solar radius. The proposed halo CME automatic analysis model was validated using a model of the past three halo CME events. As a result, a solar event that occurred at 03:38 UT on Mar. 23, 2014 was predicted to arrive at Earth at 23:00 UT on Mar. 25, whereas the actual arrival time was at 04:30 UT on Mar. 26, which is a difference of 5 hr and 30 min. In addition, a solar event that occurred at 12:55 UT on Apr. 18, 2014 was estimated to arrive at Earth at 16:00 UT on Apr. 20, which is 4 hr ahead of the actual arrival time of 20:00 UT on the same day. However, the estimation error was reduced significantly compared to the ENLIL model. As a further study, the model will be applied to many more events for validation and testing, and after such tests are completed, on-line service will be provided at the Korean Space Weather Center to detect halo CMEs and derive the model parameters.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.2
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• pp.218-227
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• 2005

Ocean resources have a very important role to meet the requirements of the people's leisure activities in a limited country, so fishing villages and fishing ports are getting more and more important as a source of supply to satisfy the demands as time goes on. There are various and far-reaching approaches to the fishing villages and fishing ports. However, studies to present the over-all direction of development policy for fishing villages and fishing ports have been short; especially the studies which have been dealing with Busan were verified to be very short relatively. As a result of survey, both officials in charge and residents in fishing villages have an enough understanding of what problems the development of fishing villages have and it's direction of development and spreading effects. In the part of the policy of developing fishing ports, officials answered that insufficient synthetic estimation was main problem in developing the fishing ports, while residents had a high recognition that local fishing ports and small scale fishing ports have had poor progress relatively. In the analysis of difference between two group about the spreading effects of developing fishing villages and fishing ports, they had affirmative opinions rather than negative ones without exemption. As mentioned above, it is a right direction to develop the existing fishing ports as well as new fishing ones to the multi-functional synthetic fishing ports. The specialized development should be made so that the special quality of coastal resources, which fishing villages have, will be made the best use of.

• The Journal of Fisheries Business Administration
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• v.46 no.3
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• pp.103-118
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• 2015

The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12C
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• pp.1256-1261
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• 2005

In this paper, we propose a low-power Booth multiplication which reduces the switching activities of partial products during multiplication process. Radix-4 Booth algorithm has a characteristic that produces the Booth encoded products with zero when input data have sequentially equal values (0 or 1). Therefore, partial products have higher chances of being zero when an input with a smaller effective dynamic range of two multiplication inputs is used as a multiplier data instead of a multiplicand. The proposed multiplier divides a multiplication expression into several multiplication expressions with smaller bits than those of an original input data, and each multiplication is computed independently for the Booth encoding. Finally, the results of each multiplication are added. This means that the proposed multiplier has a higher chance to have zero encoded products so that we can implement a low power multiplier with the smaller switching activity. Implementation results show the proposed multiplier can save maximally about $20\%$ power dissipation than a previous Booth multiplier.

• Korean Journal of Construction Engineering and Management
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• v.3 no.2 s.10
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• pp.114-120
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• 2002

Traditional bidding process and activities in public construction area has many problems in terms of the transparency and fairness of administration. And, it causes many expenses to suppliers. As part of the efforts to solve these problems, some public institutions developed the electronic bidding systems. But these systems have still problems in diverse aspects. Therefore, the purpose of this study is to analyze current bidding systems through literature survey, Questionnaire, contentment estimation and IDEF method to compare the result of the analysis with the developed electronic bidding systems and to suggest the improvement for the coming bidding systems. According to the survey, under present bidding system big problem is inconvenience of conducting process. Nearly all users of current electronic bidding systems were contented. When public institutions are planning new electronic bidding systems, standardization, security, law and bidding system consolidation must be applied. This study proposes an improved bidding system and described the effects through the improvements.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.4
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• pp.460-471
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• 2011

A port has been regarded as a significant contributor to air pollution in the surrounding areas. Port-related air pollutants are released from not only marine vessels, but also various land-side sources at ports, which include cargo handling equipment, vehicles, locomotives, and fugitive dust sources by port activities such as bulk handling and vehicle movements. However, most studies in Korea have only focused on vessel emissions and there is a lack of information on the emissions from other sources at port. In this study, in order to establish the port-related emission inventory and evaluate the relative contribution of these sources to air emissions from the Port of Incheon, the emissions from land-side sources were estimated and the CAPSS (Clean Air Policy Support System) data for vessel emissions were used. In particular, the detailed information and activity data for the cargo handling equipment source were collected and the emission factors and emissions by equipment types were calculated using U.S. EPA methodologies. Total HC, CO, $NO_x$, $PM_{10}$, and $SO_2$ emissions from port-related sources including the vessel in 2007 were calculated as 229 ton/year, 638 ton/year, 4,861 ton/year, 307 ton/year, and 3,995 ton/year, respectively. It was found that the vessel was the largest contributor to air pollutant emissions from the port, the cargo handling equipment was responsible for about from 8% to 13% of HC, CO, and $NO_x$ emissions and the resuspended road dust contributed about 39% for $PM_{10}$ emissions. The results of this study will be used to establish the management and reduction strategies of air pollution in the port.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.623-627
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• 2015

To compile a flood hazard map it is essential to identify the potential risk areas. A scenario-based numerical modeling approach is commonly used to build a flood hazard map in the case of a levee-break. The model parameters that capture peak discharge, including breach formation and progress, are important in the modeling method. In this study an earth-levee-break model is constructed under the assumption that the failure mechanism and hydraulic processes are identical for all levee-break river activities. Estimation of the hydrograph at the outlet as a function of time is highlighted. The constructed hydrograph can then serve as an upper boundary condition in running the flood routing model downstream, although flood routing is not considered in this study.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.732-737
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• 2008

As e-learning is recognized in new education form, Learning Management System that manage general activity of learning to maximize effect of education is being developed actively. Usually, Learning Management System includes course registration and learning as well as learner's learning recording and tracking, evaluation in online. But, most systems is lacking a tool that learners can collaborate with companion learners, and planning learning and set valuation basis as leading. In this paper, we can expect effective collaborative learning activities because can make debate and team project smooth by suggesting collaborative learning module that can drive voluntary participation such as group formation, learning plan, mutually estimation as leading to learner in Learning Management System of blended learning base that support online and offline environment both.

• KSBB Journal
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• v.21 no.2
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• pp.140-143
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• 2006

Acid- and enzymatic hydrolysis properties of two fructans(inulin and levan) and their oligofructoses has been investigated. At pH 1, the initial fructose release rate differs and is rapidly hydrolyzed in the order of levan oligosaccharide and inulin oligosaccharide, levan, inulin. At pH 4.5, 7 and 14, no or little amount of fructose are found from four samples. At the presence of inulinase in the reaction mixture, the fructose is rapidly produced from all samples, whilst invertase treatments show low activities. The results allow the estimation of the fructose release rate in many foodstuff processing conditions.

• Korean Journal of Community Nutrition
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• v.4 no.1
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• pp.20-29
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• 1999

This study was done to investigate the nutrient intakes and plasma biochemcial indices in 68 female college students according to their skin types. Nutrient intakes were investigated by quick estimation. The plasma TG and total cholesterol levels were measured by the Spotchem sp-4410. The plasma levels of retinol and $\alpha$-tocopherol were measured by HPLC. In addition, the activities of antioxidant defense enzymes such as plasma glutathione peroxidase(GSH-Px) and glutathione reductase(GHS-Rd) were determined. All data were statistically analyzed by SAS PC package program. The results of this study were as follows : The average age, height, weight, BMI, systolic blood pressure and diastolic blood pressure ofthe subjects were $20.9{\pm}1.9yr, 160.7{\pm}4.3cm, 53.0{\pm}7.1kg, 20.5{\pm}2.4kg/m^2, 105.3{\pm}11.5mmHg and 70.6{\pm}7.7mmHg$, respectively. Ten students(14.7%) had normal skin type, 19 students(27.9%) had dry skin type, 11 students(16.2%) had oily skin type, 17 students(25.0%) had acne and 11 students(16.2%) had mixed skin type. The intakes of energy and fats in oily skin group were significantly higher(p<0.05) than those of the dry skin group, but vitamin C intake in the mixed skin group was significantly higher(p<0.05) than those of the dry skin group, but vitamin C intake in the mixed skin group was significantly lower(p<0.05) than that in other skin types. The intakes of other nutrients were not significantly different among skin types. The analysis of lipids showed that the plasma total-cholesterol level of mixed skin group was significantly lower(p<0.05) than that of the oily skin group, whereas other lipid levels were not significantly different. The other parameters such as retinol, $\alpha$-tocopherol, GSH-Px and GSH-Rd of plasma were not significantly different among skin types. Overall results indicate that dietary intake pattern may influence skin type and thereby some blood biochemical indices can be different by skin types.