• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.27-32
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• 2021

This paper evaluates the equalization performance of FC-MMA adaptive equalization algorithm by the fixed step size that is used for the minimization of the intersymbol interference which occurs in the time dispersive communication channel. The FC-MMA has a fast convergence speed in order to adapts the new environment more rapidly in case of the time varying charateristics and the abnormal situation like as outage of the communication channel. But the algorithms operates in adative method, convegence speed is depend on fixed step size for adaptation. For this situation, its performance was evaluated by changing the step size value, the residual isi and maximum distortion and MSE performance index which means the convergence characteristics are widely adapted in the adaptive equalizer, SER were applied. As a result of computer simulation, the large step size can improves the convergence speed for reaching the steady state, but has a poor performance compared to small step size in residual values after steady state. The research result shows that the FC-MMA algorithm is applied the large step size for rapidly reaching the steady state in initial time, then adjust the small step size after reaching the steady state for reducing the residual values for equalization.

• Journal of Korea Trade
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• v.23 no.6
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• pp.131-144
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• 2019

Purpose - The purpose of this study was to investigate market power of soybeans exported by the United States to Korea. Particularly, this paper considered dichotomous characteristics of genetically modified (GM) soybeans and non-GM soybeans and conducted empirical analysis of these two segregated soybean markets to understand key tenets of market power in international soybean trade. Design/methodology - The difference in market power between GM and non-GM soybeans was analyzed using Residual Demand Elasticity (RDE) and Residual Supply Elasticity (RSE) models over the period of 2008~2018. RDE and RSE models under an imperfect competition condition were used to estimate market margins and determine whether GM and non-GM exporters or importers exercised market power in the destination market. Findings - Empirical results suggested that the U.S. had a market power on both GM and non-GM soybean exports. GM exports had greater market power than non-GM exports (14% vs. 9%). By contrast, Korea showed an inability to grab market margin or exert market power in soybean imports. Both export supply by the U.S. and import demand by Korea were found to be more responsive to price changes of GM soybeans than to prices changes of non-GM soybeans. This might be due to a self-interested, profit-seeking strategy by the exporter and many concerned consumers regarding potential adverse effects of GMOs in the importing country. Originality/value - This paper fills the literature gap by exploiting market power in both GM and non-GM markets with explicit consideration of price correlations between GM and non-GM soybeans in Korea. A number of existing studies have provided evidence for market power broadly embedded in international commodity trade. However, studies focusing on Korean markets are limited. No study has explored the country's soybean trade. Furthermore, the majority of prior studies have almost exclusively focused on the market power from a standpoint of exporting countries without discussing importers' market structure. This paper also sought to understand potentially distinguished patterns of market power between GM and non-GM markets.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.6
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• pp.106-114
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• 2000

In order to evaluate the shear characteristics of undisturbed weathered granite soil which is a typical residual soil in Korea, the mechanical properties are first investigated and discussed by carrying out a series of direct shear test and then dilatancy correction is performed by using Taylor’s correction equation. In this study, specimens are sampled at Pungam(-3, -8, -13m below ground surface), Kwangju and Iksan(-5m below ground surface), Jeonbuk. The test results are summarized as follows: 1) Mohr-Coulomb failure criterion is not linear under the low confining pressure. 2) The value of cohesion is smaller than usually determined value in low pressure region. 3) The value of strength parameter c and ø which are corrected by Taylor’s correction equation is a little bit small.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.767-786
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• 2011

This study analyzed and compared characteristic of vegetation structure in Bonghwa mountain, the base Mt. outside urban area, and Hakseoung neighborhood park, Ilsan neighborhood park and Musil neighborhood park, disconnected residual Mt. inside urban area of Wonju. Regarding vegetation of urban forest in Wonju, Quercus mongolica forest and Robinia pseudo-acacia forest were widely distributed in the base Mt. outside urban area. Quercus acutissima forest and Robinia pseudo-acacia forest were widely distributed in the disconnected residual Mt. inside urban area. Forests in both areas were managed as part of forest management campaign. Analysis on importance value of a community classified by DCA and DBH class categorized communities into three groups according to the expected ecological succession. Community B was the one to be maintained as Pinus densiflora community. Community A, D and d were expected to be maintained as Quercus spp. Community. Community C, E, F, e, f and g were classified as exotic plant community. Ecological succession was suspended in both base Mt. outside urban area and disconnected residual Mt. inside urban area. However, importance value of Quercus spp. which appeared in the understory layer and shrub layer and their DBH class showed that the potential for ecological succession of exotic plant community was higher in base Mt. outside urban area than disconnected residual Mt. inside urban area. According to the analysis on number of species and individuals and species diversity, understory and shrub layer were reduced due to Forest Management campaign and plant species which appear at an earlier stage of succession varied as time went by since the campaign began. Species diversity comparison between natural and artificial forest showed no clear difference in both base Mt. outside urban area and disconnected residual Mt. inside urban area due to man-made disruption such as thinning and brush cutting. Six communities in base Mt. outside urban area had 17.76~52.22% of similarity index. Four communities in disconnected residual Mt. inside urban area showed 13.34~37.01% of similarity index, which was lower than base Mt. outside urban area. Among naturalized plants, Tupatorium rugosum and Phytolacca americana appeared more in disconnected residual Mt. inside urban area.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.325-332
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• 1999

A manure management plan is important for all dairy operations. This experiment was conducted to determine the effect of different nitrogen(N) application rates of liquid cattle manure on the forage quality, N recovery, and total forage yields of corn-oats cropping system and soil properties at the National Livestock Research Institute, RDA, Suweon in 1997. Eight treatments consisting of no fertilizer, chemical fertilizer $320kg\;N\;ha^{-1}$ as urea, the continuous applications of 320, 640 and $960kg\;N\;ha^{-1}$ as liquid cattle manure(LCM), the residual effects of 200, 400 and $600kg\;N\;ha^{-1}$ as liquid cattle manure were arranged in a randomized complete block design with three replications. Mean plant height of fall sown oats was 70 and 61cm at the continuous application and the residual effect plots, respectively. Mean dry matter percent of fall sown oats at the residual effect plots was higher by 0.9% than that of oats at the continuous application plots, but there were no differences among all treatments. Mean crude protein(CP), acid detergent fiber(ADF), and neutral detergent fiber (NDF) contents of fall sown oats at the continuous application plots were higher by 1.0, 1.6, and 3.1%, respectively, than those of the residual effect plots. Also, there were significant differences among treatments (P<0.05). Total forage dry matter yields of corn and oats cropping system were ranged from 11,365 to $25,668kg\;ha^{-1}$ among the treatments. The yield was orderly ranked as LCM $960kg\;N\;ha^{-1}$ > LCM $600kg\;N\;ha^{-1}$ > LCM $640kg\;N\;ha^{-1}$ > LCM $400kg\;N\;ha^{-1}$ (P<0.05). Compared with the control, manurial value(MV) was 158 and 139% for the plot of the LCM $960kg\;N\;ha^{-1}$ and that of the LCM $600kg\;N\;ha^{-1}$, respectively. N recovery percent of fall sown oats was the highest at the plot of the LCM $200kg\;N\;ha^{-1}$ by 50%, and then was higher in order of the LCM $400kg\;N\;ha^{-1}$, LCM $600kg\;N\;ha^{-1}$, and LCM $320kg\;N\;ha^{-1}$. Contents of exchangeable cation in the soil of the residual effect plots was higher than that of the continuous application plots. These results suggest that the LCM $600kg\;N\;ha^{-1}$ may be the most effective in total forage dry matter yields, manurial value, N recovery, and utilizing liquid manure N under the corn and oats double cropping system.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1582-1588
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• 2005

This study aimed to evaluate the effects of silage additives on the fermentation qualities and residual mono- and disaccharides composition of silages. Forage Oats (Avena sativa L.) and Italian Ryegrass (Lolium multiflorum Lam.) were ensiled with glucose, sorbic acid and pre-fermented juice of epiphytic lactic acid bacteria (FJLB) treatments for 30 days. In both species grass silages, although the respective controls had higher contents of butyric acid (20.86, 33.45g $kg^{-1}$ DM) and ammonia-N/total nitrogen (100.07, 114.91 g $kg^{-1}$) as compared with other treated silages in forage oats and Italian ryegrass, the fermentation was clearly dominated by lactic acid bacteria. This was well indicated by the low pH value (4.27, 4.38), and high lactic acid/acetic acid (6.53, 5.58) and lactic acid content (61.67, 46.85 g $kg^{-1}$ DM). Glucose addition increased significantly (p<0.05) lactic acid/acetic acid, and significantly (p<0.05) decreased the values of pH and ammonia-N/total nitrogen, and the contents of butyric acid and volatile fatty acids as compared with control, however, there was a slightly but significantly (p<0.05) higher butyric acid and lower residual mono- and di-saccharides as compared with sorbic acid and FJLB additions. Sorbic acid addition showed the lowest ethanol, acetic acid and ammonia-N/total nitrogen, and highest contents of residual fructose, total mono- and di-saccharides and dry matter as well as high lactic acid/acetic acid and lactic acid content. FJLB addition had the lowest pH value and the highest lactic acid content, the most intensive lactic acid fermentation occurring in FJLB treated silages. This resulted in the faster accumulation of lactic acid and faster pH reduction. Sorbic acid and FJLB additions depressed clostridia or other undesirable bacterial fermentation, thus this decreased the water-soluble carbohydrates loss and saved the fermentable substrate for lactic acid fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.11
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• pp.1699-1704
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• 2007

This experiment was carried out to evaluate the effects of adding encapsulated-glucose, glucose, sorbic acid or prefermented juice of epiphytic lactic acid bacteria (FJLB) on the fermentation quality and residual mono- and disaccharide composition of Italian ryegrass (Lolium multiflorum Lam) silages. The additive treatments were as follows: (1) control (no addition), (2) encapsulated-glucose addition at 0.5% for glucose, (3) glucose addition at 1%, (4) sorbic acid addition at 0.1%, (5) FJLB addition at a theoretical application rate of $2.67{\times}10^5$ CFU (colony forming unit) $g^{-1}$, on a fresh weight basis of Italian ryegrass. Although control and encapsulated-glucose treatments had higher contents of butyric acid (33.45, 21.50 g $kg^{-1}$ DM) and ammonia-N/Total nitrogen (114.91, 87.01 g $kg^{-1}$) as compared with the other treated silages, the fermentation in all silages was clearly dominated by lactic acid. This was well indicated by the low pH (4.38-3.59), and high lactic acid/acetic acid (4.39-22.97) and lactic acid content (46.85-121.76 g $kg^{-1}$ DM). Encapsulated-0.5% glucose and glucose addition increased lactic acid/acetic acid, and significantly (p<0.05) decreased ammonia-N/total nitrogen, and the contents of butyric acid and total volatile fatty acids (VFAs) as compared with the control. However, there were higher butyric acid and lower residual mono-and di-saccharides on the two treatments as compared with sorbic acid and FJLB addition, and their utilization efficiency of water soluble carbohydrates (WSC) was lower than that of both sorbic acid and FJLB additions. Sorbic acid addition showed the lowest content of ethanol and ammonia-N/total nitrogen, and the highest content of residual fructose and total mono-and disaccharides as well as the higher lactic acid/acetic acid value. Sorbic acid addition decreased the loss of mono-and disaccharides, and inhibited the activity of clostridial and other undesirable bacteria, and greatly increased the utilization efficiency of fermentable substrates by epiphytic LAB. FJLB addition had the lowest pH value and the highest lactic acid content among all additive treatments, with the most intensive lactic acid fermentation occurring in FJLB treated silage. This resulted in the faster accumulation of lactic acid and faster pH reduction. Sorbic acid and FJLB addition depressed clostridia or other undesirable bacterial fermentation which decreased the WSC loss and saved the fermentable substrate for lactic acid fermentation.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.440-445
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• 2010

This study was carried out to investigate the toxicities of five registered insecticides to the Lycorma delicatula nymphs and adults. Insecticidal activities were evaluated by testing systemic and residual effects in the laboratory, and control efficacy in the vineyard. For the 3rd nymphal instars and adults, etofenprox+diazinon, chlorpyrifos, etofenprox, dinotefuran and imidacloprid showed perfect insecticidal activity. The systemic effects of dinotefuran and etofenprox+diazinon on grape roots at half concentration were showed the adult mortality of 82.2% and 84.4%, respectively. Chlorpyrifos at recommended concentration was showed mortality of 86.0%. The leaf systemic effects at recommended and half concentrations of all insecticides except dinotefuran were lower than 65% but the mortality at double concentration of chlorpyrifos, dinotefuran, etofenprox were more than 82%. The residual effect between etofenprox+diazinon and dinotefuran at recommended and double concentrations were 100% at 14 days after treatment, the other insecticides have low efficacy. All the four insecticides showed 87% control value on nymphs in the field test and adults appeared more than 96% control value st and adinotefuran, etofenprox+diazinon, however, the other insecticides decreased to 59.1 % and 61.2%. Therefore, dinotefuran and etofenprox+diazinon showing high systemic effects to roots and long residual effects to leafs have high control efficacies.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.530-537
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• 2000

Quality characteristics of strawberry jams made of 2 different strawberry cultivars, Bogyo-joseng and Suhong, with 25, 50, 75, 100% fructo-oligosaccharide in place of sucrose were evaluated. Moisture content of Suhong jam was higher than Bogyo-joseng jam. pH of Bogyo-joseng and Suhong jam was not different. The lightness, redness and yellow-ness of Bogyo-joseoung jam were higher than those of Suhong jam. Spreadmeter value of jams decreased with addition of fructo-oligosaccharide. The sweetness of Suhong jam was higher than Bogyo-joseng. Reducing sugar content of Suhong jam was higher than Bogyo-joseng jam. More of fructo-oligosaccharide added, reducing sugar content of jam increased. Residual anthocyanin in Bogyo-joseng strawberry jam was decreased by addition of fructo-oligosaccharide. However, the residual anthocyanin content of Suhong strawberry jams with fructo-oligosaccharide was lower than that of sugar-only control jam with an exception of 50% fructo-oli-gosaccharide jam. The 50% fructo-oligosaccharide jam had a higher residual anthocyanin content than sugar-only jam. As the addition rate of fructo-oligosaccharide increased, springiness and cohesiveness of jam increased, while resilience decreased. In sensory evaluation, Bogyo-joseng strawberry jams obtained highest score with 50% fructo-oligosaccharide, while Suhong strawberry jam was favored most with 25% fructo-oligosaccharide.

• KSBB Journal
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• v.9 no.4
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• pp.365-371
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• 1994

The effects of ratios of initial concentration of carbon source to the initial concentration of nitrogen source in the fermentation media on both the yields of PHB fermentation variables and the accumulation of poly-${\beta}$-hydroxybutyric acid(PHB) were investigated. The fermentation media were composed of the combination of varing glucose concentrations, 10, 20, 25, 30, 40, $50g/\ell$ and the NH4Cl concentrations 0.33, 0.4, 0.5, 1.5, 3, $5g/\ell$. The yield of biomass on glucos, Yx/s, decreased very slowly according to the increase of the ratio of C to N. And the yield became constant at 0.35(g biomass/g glucose) with the ratio higher than 70. The yield of residual biomass, Yx/s, also decreased with the ratio of C to N and finally showed a constant value of 0.065(g residual biomass/g glucose) when the ratio was higher than 65. In accordance with the augmentation of the ratio, the yield of PHB, YPHB/S, however, increased and showed the maximum value of 0.35 (g PHB/g glucose) between 40 and 60 of the ratio. The maximum yield of PHB to the change of biomass, YPHB/S, was 0.87(g PHB/g biomass), and the yie1d YPHB/RX, was 4.2(g PHB/g residual biomass). The maximum accumulation percent of PHB to the final biomass was 81% when the ratio was higher than 67.