• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1605-1613
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• 2020

The tidal channel is a coastal sedimentary terrain that plays the most important role in the formation and development of tidal flats, and is considered a very important index for understanding and distribution of tidal flat sedimentation/erosion terrain. The purpose of this study is to understand the changes in tidal channels by a period after the opening of the floodgate of the seawall in the reclaimed land of Sihwa Lake using KOMPSAT high-resolution multispectral satellite image data and to evaluate the applicability and efficiency of high-resolution satellite images. KOMPSAT 2 and 3 images were used for extraction of the tidal channels' lineaments in 2009, 2014, and 2019 and were applied to supervised classification method based on Principal Component Analysis (PCA), Artificial Neural Net (ANN), Matched Filtering (MF), and Spectral Angle Mapper (SAM) and band ratio techniques using Normalized Difference Water Index (NDWI) and MF/SAM. For verification, a numerical map of the National Geographic Information Service and Landsat 7 ETM+ image data were utilized. As a result, KOMPSAT data showed great agreement with the verification data compared to the Landsat 7 images for detecting a direction and distribution pattern of the tidal channels. However, it has been confirmed that there will be limitations in identifying the distribution of tidal channels' density and providing meaningful information related to the development of the sedimentary process. This research is expected to present the possibility of utilizing KOMPSAT image-based high-resolution remote exploration as a way of responding to domestic intertidal environmental issues, and to be used as basic research for providing multi-platform-image-based convergent thematic maps and topics.

• The Korean Journal of Franchise Management
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• v.1 no.1
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• pp.19-42
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• 2010

Since circulation market whole surface opening, traditional market is real condition that is looked away more gradually to consumer as reasons of international retail firms and domestic enterprise firms to enter distribution industry, internet mail order rapid increase by information-oriented society, the pursuit of upgradation and normalization by elevation of income level and consumption pattern change that consideration convenience with young consumers as the central figure. Therefore, the purpose of this study is to analyze stagnation cause of traditional market and problem within a change of new distribution environment, and to develop new approaches for dealing with domestic traditional market relationship prompting competition through activation example analysis of foreign traditional market and domestic traditional market. The result of the study indicated that there are a lot of cases that are begun by a few's merchant with leadership that has been will which is strong in activation in beginning in market's occasion that succeed in activation. In particular, software side such as operational efficiency or marketing expertise strengthening of management is that effect is high relatively than hardware side market activation. Also essential to the settlement of credit transactions using credit cards is important for expanding the effort, for the expansion of credit card merchant credit card advantage and raise awareness among traders about the expected effects is needed. Though these study finding submits plan that create market ecosystem so that many consumers may become place that could visit naturally and create pleasure and convenience, and time, monetary, psychological value of shopping to traditional market, there is sense.

• Structural Engineering and Mechanics
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• v.90 no.6
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• pp.611-633
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• 2024

This study intends to investigate the response of multi-cell (MC) beams to flexural loads in which the primary reinforcement is composed of both metallic and non-metallic materials. "Multi-cell" describes beam sections with multiple longitudinal voids separated by thin webs. Seven reinforced concrete MC beams measuring 300×200×1800 mm were tested under flexural loadings until failure. Two series of beams are formed, depending on the type of main reinforcement that is being used. A control RC beam with no openings and six MC beams are found in these two series. Series one and two are reinforced with metallic and non-metallic main reinforcement, respectively, in order to maintain a constant reinforcement ratio. The first crack, ultimate load, deflection, ductility index, energy absorption, strain characteristics, crack pattern, and failure mode were among the structural parameters of the beams under investigation that were documented. The primary variables that vary are the kind of reinforcing materials that are utilized, as well as the kind and quantity of mesh layers. The outcomes of this study that looked at the experimental and numerical performance of ferrocement reinforced concrete MC beams are presented in this article. Nonlinear finite element analysis (NLFEA) was performed with ANSYS-16.0 software to demonstrate the behavior of composite MC beams with holes. A parametric study is also carried out to investigate the factors, such as opening size, that can most strongly affect the mechanical behavior of the suggested model. The experimental and numerical results obtained demonstrate that the FE simulations generated an acceptable degree of experimental value estimation. It's also important to demonstrate that, when compared to the control beam, the MC beam reinforced with geogrid mesh (MCGB) decreases its strength capacity by a maximum of 73.33%. In contrast, the minimum strength reduction value of 16.71% is observed in the MC beams reinforced with carbon reinforcing bars (MCCR). The findings of the experiments on MC beams with openings demonstrate that the presence of openings has a significant impact on the behavior of the beams, as there is a decrease in both the ultimate load and maximum deflection.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.119-133
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• 2020

Fama asserted that in an efficient market, we can't make a trading rule that consistently outperforms the average stock market returns. This study aims to suggest a machine learning algorithm to improve the trading performance of an intraday short volatility strategy applying asymmetric volatility spillover effect, and analyze its trading performance improvement. Generally stock market volatility has a negative relation with stock market return and the Korean stock market volatility is influenced by the US stock market volatility. This volatility spillover effect is asymmetric. The asymmetric volatility spillover effect refers to the phenomenon that the US stock market volatility up and down differently influence the next day's volatility of the Korean stock market. We collected the S&P 500 index, VIX, KOSPI 200 index, and V-KOSPI 200 from 2008 to 2018. We found the negative relation between the S&P 500 and VIX, and the KOSPI 200 and V-KOSPI 200. We also documented the strong volatility spillover effect from the VIX to the V-KOSPI 200. Interestingly, the asymmetric volatility spillover was also found. Whereas the VIX up is fully reflected in the opening volatility of the V-KOSPI 200, the VIX down influences partially in the opening volatility and its influence lasts to the Korean market close. If the stock market is efficient, there is no reason why there exists the asymmetric volatility spillover effect. It is a counter example of the efficient market hypothesis. To utilize this type of anomalous volatility spillover pattern, we analyzed the intraday volatility selling strategy. This strategy sells short the Korean volatility market in the morning after the US stock market volatility closes down and takes no position in the volatility market after the VIX closes up. It produced profit every year between 2008 and 2018 and the percent profitable is 68%. The trading performance showed the higher average annual return of 129% relative to the benchmark average annual return of 33%. The maximum draw down, MDD, is -41%, which is lower than that of benchmark -101%. The Sharpe ratio 0.32 of SVS strategy is much greater than the Sharpe ratio 0.08 of the Benchmark strategy. The Sharpe ratio simultaneously considers return and risk and is calculated as return divided by risk. Therefore, high Sharpe ratio means high performance when comparing different strategies with different risk and return structure. Real world trading gives rise to the trading costs including brokerage cost and slippage cost. When the trading cost is considered, the performance difference between 76% and -10% average annual returns becomes clear. To improve the performance of the suggested volatility trading strategy, we used the well-known SVM algorithm. Input variables include the VIX close to close return at day t-1, the VIX open to close return at day t-1, the VK open return at day t, and output is the up and down classification of the VK open to close return at day t. The training period is from 2008 to 2014 and the testing period is from 2015 to 2018. The kernel functions are linear function, radial basis function, and polynomial function. We suggested the modified-short volatility strategy that sells the VK in the morning when the SVM output is Down and takes no position when the SVM output is Up. The trading performance was remarkably improved. The 5-year testing period trading results of the m-SVS strategy showed very high profit and low risk relative to the benchmark SVS strategy. The annual return of the m-SVS strategy is 123% and it is higher than that of SVS strategy. The risk factor, MDD, was also significantly improved from -41% to -29%.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.174-175
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• 2012

(In, Ga) N-based III-nitride semiconductor materials have been viewed as the most promising materials for the applications of blue and green light emitting devices such as light-emitting diodes (LEDs) and laser diodes. Although the InGaN alloy can have wide range of visible wavelength by changing the In composition, it is very hard to grow high quality epilayers of In-rich InGaN because of the thermal instability as well as the large lattice and thermal mismatches. In order to avoid phase separation of InGaN, various kinds of structures of InGaN have been studied. If high-quality In-rich InGaN/GaN multiple quantum well (MQW) structures are available, it is expected to achieve highly efficient phosphor-free white LEDs. In this study, we proposed a novel InGaN double hetero-structure grown on GaN nano-pyramids to generate broad-band red-color emission with high quantum efficiency. In this work, we systematically studied the optical properties of the InGaN pyramid structures. The nano-sized hexagonal pyramid structures were grown on the n-type GaN template by metalorganic chemical vapor deposition. SiNx mask was formed on the n-type GaN template with uniformly patterned circle pattern by laser holography. GaN pyramid structures were selectively grown on the opening area of mask by lateral over-growth followed by growth of InGaN/GaN double hetero-structure. The bird's eye-view scanning electron microscope (SEM) image shows that uniform hexagonal pyramid structures are well arranged. We showed that the pyramid structures have high crystal quality and the thickness of InGaN is varied along the height of pyramids via transmission electron microscope. Because the InGaN/GaN double hetero-structure was grown on the nano-pyramid GaN and on the planar GaN, simultaneously, we investigated the comparative study of the optical properties. Photoluminescence (PL) spectra of nano-pyramid sample and planar sample measured at 10 K. Although the growth condition were exactly the same for two samples, the nano-pyramid sample have much lower energy emission centered at 615 nm, compared to 438 nm for planar sample. Moreover, nano-pyramid sample shows broad-band spectrum, which is originate from structural properties of nano-pyramid structure. To study thermal activation energy and potential fluctuation, we measured PL with changing temperature from 10 K to 300 K. We also measured PL with changing the excitation power from 48 ${\mu}W$ to 48 mW. We can discriminate the origin of the broad-band spectra from the defect-related yellow luminescence of GaN by carrying out PL excitation experiments. The nano-pyramid structure provided highly efficient broad-band red-color emission for the future applications of phosphor-free white LEDs.

• The korean journal of orthodontics
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• v.30 no.5 s.82
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• pp.553-563
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• 2000

Horseshoe Expander is one of Slow Maxillary Expansion(SME) which aims to accommodate the contra- lateral expansion and midpalatal suture expansion or the palate. The appliance consists of skeleton type strew embedded in split Horseshoe appliance. It is the objectives of the presentation to manifest the changes in dental & craniofacial components subsequent to the application of Horseshoe Expander. The subjects for this study consisted of 32 patients (mean age : 12.7). frontal, lateral cephalometric headfilm were taken and study casts were fabricated before and after expansion. 24 items were measured, compared preexpansion with postexpansion. Especially, palatal volume was measured by means of 'Hydro-measurement method'. Tooth axis measurement on the dental casts were made with Universal bevel protractor, and Horseshoe Expander group were compared with RME group. This study of changes to maxillary expansion with Horseshoe Expander revealed the following significant results. 1. Triangular-shaped expansion pattern appeared in frontal cephalometric headfilm. 2. Palatal plane, occlusal plane, mandibular plane and upper incisor to FH increased in lateral cephalometrir headfilm. 3. Palatal volume increased significantly. A slight bite opening, reduction of occlusal contact points showed in dental casts. 4. A 2.2:1 ratio of the amount of intermolar width in maxilla(orthodontic movement) to maxillary width (orthopedic movement) was determined. 5. Horseshoe Expander group has less buccal tipping tendency than RME group, by taking high correlation coefficients in the upper second premolar and first molar. It was suggested that Horseshoe Expander showed less orthodontic changes, less buccal tipping tendency. In addition, it was effective in maxillary expansion.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.2
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• pp.187-198
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• 1997

This experiment was conducted to evaluate effects of wilting and additives on fermetation characteristics, quality and aerobic stability of silage of rye(Seca1e cereale L.) harvested at the early heading stage. Harvested rye was wilted or mixed with beet pulp and then treated with formic acid or lactic acid bacteria(LAB) inoculant. Treatments were consisted of direct cut(DC), wilted(WT), beet pulp added(BP), direct cut and formate applied(DF), wilted and formate applied(WF), beet pulp and formate applied(BF), direct cut and LAB inoculated(DL), beet pulp added and LAB inoculated(BL), and wilted and LAB inoculated(WL) silages. Afler 70 days of ensiling period, the silages were opened and exposed to air for 7 days, and the silages of opening day(0 day) were compared with the silages exposed to air for 7 days(7 day). 1. LAB inoculated rye silages(DL, WL, BL) lowered pH values effectively eom the third day of ensiling and showed most stable pattern of pH changes during the initial fermentation process. Direct cut and formate applied(DF), beet pulp and formate applied(BF) and beet pulp added(BP) silages were also effective in lowering pH from the seventh day thai direct cut treatment(DC). 2. pH was low below 3.7 in all treatments of 0 day. After 7-day period of aerobic exposure, DL and WL showed considerable increases in pH from 3.5 and 3.4 to 8.3 and 6.4, respectively. 3. Direct cut rye silages(DF, DC, DL) and beet pulp and formate treatment(BF) produced effluent of 121.2, 85.9, 80.3 and 34.2 mlkg, respectively and these were greater than others(P<0.01). Beet pulp retained 1.61 I/kg of effluent at the application rate of 50 kg/t in comparing BP with DC, and formate application increased the amount of effluent in comparing DF and BF with DC and BP, respectively(P<0.01). 4. Beet pulp and LAB treatment(B1) was highest in content of lactate as 3.1% and formate treated silages(DF, WF, BF) showed lower content of lactate and total acid than others. LAB inoculated(D1, WL, BL) and wilted (WT) silages were graded to be good quality as a second group by the Flieg's score. Formate applied silages (DF, WF, BF) were graded as a foum group lower than DC by one. 5. Residual content of WSC of rye silage was higher in BP, BF, DL and BL than direct cut treatment(M3) (P< 0.01). Formate application had a tendency to increase the content of residual content of WSC. 6. For the ratio of NH3-N to Total N, wilted and LAB inoculated(W1) and direct cut and LAB inoculated(D1) silages were lowest on 0 day as 8.9 and 9.3% respectively. But after 7-day period of aerobic exposure, WL and DL showed largest increase of the ratio of $NH_3-N$ to Total N from 0 day(P<0.01). 7. On 0 day wilted(WT), beet pulp and formate treatment(BF), and beet pulp and LAB treatment(B1) were lower than direct cut treatment(DC) for NDF and ADF concentrations consistently. Formate applied silages (DF, WF, BF) made little change in ADF and NDF concentrations during 7 day period of aerobic exposure. DL and WL showed a large increase in ADF and NDF concentrations under aerobic condition(P<0.01). 8. IVDMD values of wilted(WT), beet pulp added(BP), wilted and LAB inoculated(W1) and beet pulp added and LAB inoculated(B1) silages were higher than direct-cut treatmentPC) as 84.7, 84.7, 84.4 and 83.0%, respectively on 0 day. But during 7-day period of aerobic exposure, a great decreae in IVDMD of WL was showed(P<0.01). The experimental results indicate that wilted silage(WT) could be recommended as the most effective treatment for reducing efluent and increasing quality and feed value of rye silage without deteriorating aerobic stability more than direct cut treatment(DC). Additionally, under unfavorable weather condition beet pulp added and LAB inoculated treatment(T3L) might be the possible alternative for successful ensiling of forage rye.

• Korean Journal of Ecology and Environment
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• v.44 no.1
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• pp.1-8
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• 2011

We investigated developmental stages of embryo and early life history of the Korean indigenous fish, the northern loach, Cobitis pacifica in 2009 in order to understand fundamental knowledges for conservation of this species. Eggs were obtained after hormones injections (LHRH-a, HCG) and were artificially fertilized by the dry method. The embryo was spherical, separative demersal, faint white, and averaged $1.09{\pm}0.04\;mm$ (n=20) in diameter. The hatching of the embryo took place in about 48 hours after fertilization under water temperature of $21.0{\sim}24.0^{\circ}C$ and the newly hatched larvae averaged $2.87{\pm}0.05\;mm$ (n=20) in total length (TL). Four days after hatching, the larvae grew up to $6.86{\pm}0.10\;mm$ (n=10) in TL and york sac absorption, mouth and anus opening were shown. Fourteen days after hatching, most of fin-rays appeared at $10.71{\pm}0.34\;mm$ (n=10) in TL and color spots on the body surface were attained. Twenty six days after hatching, the larvae grew up to $14.88{\pm}0.45\;mm$ (n=10) in TL, and all their fin-rays were formed. Therefore, according to current study regarding the morphological development of Cobitis pacidica, the conversion from larval to juvenile stages occurred at 26 days after hatching. Eighty days after hatching, the larvae were $33.3{\pm}1.25\;mm$ (n=10), and their body shape and color pattern were similar to adult fish. In this study, embryonic development and early life history of the northern loach, Cobitis pacifica show morphological characteristics of Cobitidae family. We expected that our results can be used as an fundamental knowledges for restoration study of indigenous fish species.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.1-20
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• 1997

Skeletal Class III malocclusions are growth-related discrepancies, and the problems are more severe until growth is complete. Causes of skeletal Class III malocclusion are classified into mandibular overgrowth, maxillary deficiency, and combination of the two. Face mask has been recommended for treatment of Class III malocclusion with maxillary deficiency in the early time of growth. Numerous experiments were performed and clinical studies have been reported on face mask ; nevertheless, studies on profile changes and stability after treatment of face mask are considered to be somewhat insufficient. The author selected 50 patients who can be checked for follow-up. They had been diagnosed as skeletal Class III malocclusion with maxillary deficiency and then treated with face mask ; the sample group was divided according to sex, treatment beginning age, palatal suture opening (intraoral appliance). For each group, changing pattern of facial profile and stability of treatment observed, and comparison with 20 Korean normal children(Angle's Class I). The following results were obtained. 1. skeletal, dental, and soft tissue measurements indicated more changes in the amounts of maxillary forward movement during face mask treatment. 2. R.P.E. group showed more significant maxillofacial changes and La-Li group showed more dental changes. 3. Growth changes of maxilla induced in the treatment group during wearing face mask were much more than those of normal group. 4. Growth changes of maxilla in the treatment group after treatment of face mask were less than those of normal group. From the obtained aata, it can be concluded that there was a stimulative effect on forward growth of maxilla during the use of face mask ; however, on removal of face mask, the stimulative effect was eliminated and undergrowth tendency of maxilla resumed.

• Journal of the Daesoon Academy of Sciences
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• v.40
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• pp.77-114
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• 2022

The purpose of this study is to analyze the ideological background, legal composition, and separation of powers contained within the institutional devices of The Dao Constitution based on the basic principles of the legal system, which would be embodied in The Constitution of the Republic of Korea. The ideological background of The Dao Constitution is that of the religion, Daesoon Jinrihoe. In Daesoon Jinrihoe, it is held that the Supreme God, Sangje, determined that Mutual Contention, the ruling pattern of the Former World, ran contrary to His divine will and this endangered the world as nature and humans had also fallen into Mutual Contention. As an act of divine intervention, Sangje established Mutual Beneficence so that nature and humanity could follow Mutual Beneficence as a paradigm shift culminating in a Great Opening of the universe. Sangje, the agent behind the paradigm shift, revealed His divine will that humans transform into mutually beneficent humans. Therefore, The Dao Constitution was written to be a set of fundamental norms based on the 'rights and obligations of the members of Daesoon Jinrihoe' to accept and implement the will of Sangje as it applies to each member's mission. The legal composition of The Dao Constitution consists of the body and supplementary provisions. The text consists of general rules, moral rights and obligations, origins, and institutional devices. Institutional devices include the Central Council, the Institute of Propagation and Edition, the Institute of Religious Services, Works, Financial Management, and the Institute of Audit and Inspection. The legal composition of The Dao Constitution is similar to that of the Constitution. The difference is that while the Constitution applies a 'principle of maximum rights and minimum obligations,' The Dao Constitution stipulates more obligations than rights in order to complete the mission of the members. The principle of separation of powers is applied to the institutional devices in The Dao Constitution. In The Dao Constitution, the organizational form of the central headquarters has been divided into a 'before and after' scheme surrounding the death of Dojeon. The organizational form of the central headquarters prior to Dojeon's death was similar to a Constitutional Monarchy. After the death of Dojeon, the central headquarters' organizational form became similar to a parliamentary cabinet system. The separation of powers at central headquarters is divided among a legislative power (the Central Council), an executive power (the Institute of Religious Services), and a judicial power (the Institute of Audit and Inspection). The separation of powers within the functions of the central government first occurs between the Central Council and its employees, then between the Central Council and the Institute of Auditing and Inspection, and also between the Legislative Government and the Institute of Religious Services. Furthermore, the principle of a vertical separation of powers exists between the central headquarters and the local organization.