• Journal of Korea Water Resources Association
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• v.49 no.7
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• pp.625-634
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• 2016

Three leading agencies under different ministries - Korea Meteorological Administration (KMA) in the ministry of Environment, Han river control office in the Ministry of Land, Infrastructure and Transport (MOLIT) and Weather Group of ROK Air Force in the Ministry of National Defense (MND) - have been operated radars in the purpose of observing weather, hydrology and military operational weather in Korea. Eight S-band dual-pol. radars have been newly installed or replaced by these ministries over different places by 2015. However each ministry has different aims of operating radars, observation strategies, data processing algorithms, etc. Due to the differences, there is a wide level of accuracy on observed radar data as well as the composite images made of the cross governmental radar measurement. Gaining fairly high level of accuracy on radar data obtained by different agencies has been shared as a great concern by the ministries. Thus, "an agreement of harmonizing weather and hydrological radar products" was made by the three ministries in 2010. Particularly, this is very important to produce better rainfall estimation using the cross governmental radar measurement. Weather Radar Center(WRC) in KMA has been developed an empirical method using measurements observed by Yongin testbed radar. This study is aiming to examine the efficiency of the empirical method to improve the accuracies of radar rainfalls estimated from cross governmental dual-pol. radar measurements. As a result, the radar rainfalls of three radars (Baengnyeongdo, Biseulsan, and, Sobaeksan Radar) were shown improvement in accuracy (1-NE) up to 70% using data from May to October in 2015. Also, the range of the accuracies in radar rainfall estimation, which were from 30% to 60% before adjusting polarimetric variables, were decreased from 65% to 70% after adjusting polarimetric variables.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.103-108
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• 1980

In order to elucidate the source of bacterial contamination during processing U. H. T. milk and to ensure its hygienic control, bacterial numbers were determined each step of the processes on the milks, water, tanks and pipe lines, and environments. The results obtained were as follows. 1. The viable numbers of mesophilic bacteria were $1.2{\sim}1.9{\times}10^7/ml$ of milk in the storage tank and in pipe line connected to the preheater. These were decreased to $7.0{\times}10cells{\sim}3.4{\times}10^2cells/ml$ after preheating and homogenization, and to $1.0{\times}10cells/ml$ after sterilization, then increased up to $1.2{\times}10^2cells/ml$ after packing. 2. The numbers of thermophilic bacteria were $5.0{\times}10cells{\sim}1.0{\times}10^2cells/ml$ of milk before preheating ; $3.0{\sim}5.0{\times}10cells/ml$ after homogenization ; none in the sterilizer and surge tank ; and $1.0{\sim}8.0{\times}10cells/ml$ after packing. 3. The levels of psychrophilic bacteria were $1.0{\sim}3.7{\times}10^6cells/ml$ of milk before preheating ; $1.0{\sim}4.0{\times}10cells/ml$ after homogenization ; $1.0{\times}10cells/ml$ after sterilization ; and $2.0{\times}10cells{\sim}2.5{\times}10^2cells/ml$ after packing. 4. No coliform bacteria were detected after sterilization, while the level before preheating was $2.1{\times}10^4cells{\sim}6.5{\times}10^5cells/ml$ of milk. 5. The level of mesophiles was $3.0{\times}10cells{\sim}7.4{\times}10^2cells$ in the environmental air, water supply, and unfilled packs and bottles ; that of thermophiles $1.0{\sim}3.0{\times}10cells$ in the air and water ; that of psychrophiles $1.0{\times}10cells{\sim}1.0{\times}10^2cells$ in the air, water, packs and bottles ; however no coliform was detected.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.588-596
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• 2011

Wild grape extract (WGE) was added into hwajeon at different concentrations (0, 5, 15, 30, 50% of water). The resulting hwajeon were analyzed for their physicochemical and sensory properties. With increasing concentrations of WGE, the pH of dough and hwajeon decreased, and their degrees brix and color intensity increased, presumably due to the presence of tartaric acid, sugar, and anthocyanin in the WGE. The WGE-enriched hwajeon showed higher hardness, gumminess, and chewiness than control hwajeon, which might have been because the sugar and tartaric acid in the WGE partially inhibited starch gelatinization during heat processing. Nevertheless, all the sensory properties and preference were higher in WGE-enriched hwajeon than controls, which could be partially attributed to the fact of that the WGE-enriched hwajeon retained relatively higher moisture. It is suggested that WGE-enriched hwajeon with high preference could be prepared without loss of hwajeon quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.105-110
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• 2009

The effects of heat treated and herb added garlic (Allium sativum L.) on the antioxidant activities were investigated. Boiling ($100^{\circ}C$, 60 min), steaming ($100^{\circ}C$, 30 min), baking ($120^{\circ}C$, 10 min), or high temperature and high pressure (HTHP, $120^{\circ}C$, 20 min, 1.5 kgf/$cm^2$) were applied, and several herbs were added to garlic. Hunter color L-value of heated garlic was significantly decreased, compared to that of control (fresh garlic), whereas a-value and b-value were increased (p<0.05). In the texture profile analysis, hardness, chewiness and gumminess of heated garlic were decreased, whereas adhesiveness was increased. The antioxidant activities determined by DPPH and hydroxyl radical scavenging activities were decreased in HTHP garlic. The pungent taste and garlic odor were the weakest in HTHP garlic. Especially, the pungent taste of HTHP garlic was not detectable. Green tea among several herbs (bay leaf, cinnamon bark, pine needles) showed the highest DPPH radical scavenging activity. Addition of green tea to HTHP garlic was appropriate for decreasing antioxidative activity of HTHP garlic compared to fresh garlic. Based on these results, it was suggested that high temperature and high pressure treated garlic with green tea might be very useful as a substitute for odorless functional garlic products.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.1-12
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• 2010

The aim of this study was to evaluate the preventive effect of commercially available anticariogenic products, specifically, the tooth cream containing Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP), fluoride varnish and low-level fluoride mouthrinse on enamel erosion induced by carbonated beverage in a short period of time. Enamel specimens were treated as follows and were then kept in artificial saliva for 24 hours followed by further processing by alternately soaking them in Cola beverage and in distilled water for 1 minute each five times. Group 1: control group (no treatment) Group 2: tooth cream with CPP-ACP Group 3: fluoride varnish (1,000 ppm F) Group 4: low-level fluoride mouthrinse (227 ppm F) Group 5: fluoride varnish + tooth cream with CPP-ACP Group 6: low-level fluoride mouthrinse + tooth cream with CPP-ACP Microhardness and erosion depth were measured and the mineral loss of each specimen was evaluated by measuring the volumetric fluorescence change(${\Delta}Q$) against the stable fluorescent grid using quantitative light-induced fluorescence(QLF). The experiment lasted for 6 days repeated each day. The results were as follows: 1. The microhardness was increased as follows: Group $1{\leq}2{\leq}4$<6<$3{\fallingdotseq}5$. 2. The mean erosion depth was increased as follows: Group $5{\fallingdotseq}3$<6<$4{\fallingdotseq}2{\fallingdotseq}1$. 3. The ${\Delta}Q$ was increased as follows: Group $1{\fallingdotseq}2{\leq}4{\leq}6{\leq}3{\fallingdotseq}5$. The decrement of ${\Delta}Q$ was similar between group 1 and 2, group 4 and 6 and group 3 and 5. 4. The ${\Delta}Q$ showed positive correlation with microhardness (r=0.96, p<0.05), while it was negatively correlated to erosion depth (r=-0.96, p<0.05).

• The KIPS Transactions:PartC
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• v.10C no.5
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• pp.625-634
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• 2003

More than a decade after its initial proposal, deployment of IP Multicast has been limited due to the problem of traffic control in multicast routing, multicast address allocation in global internet, reliable multicast transport techniques etc. Lately, according to increase of multicast application service such as internet broadcast, real time security information service etc., overlay multicast is developed as a new internet multicast technology. In this paper, we describe an overlay multicast protocol and propose fast join mechanism that considers switching of the tree. To find a potential parent, an existing search algorithm descends the tree from the root by one level at a time, and it causes long joining latency. Also, it is try to select the nearest node as a potential parent. However, it can't select the nearest node by the degree limit of the node. As a result, the generated tree has low efficiency. To reduce long joining latency and improve the efficiency of the tree, we propose searching two levels of the tree at a time. This method forwards joining request message to own children node. So, at ordinary times, there is no overhead to keep the tree. But the joining request came, the increasing number of searching messages will reduce a long joining latency. Also searching more nodes will be helpful to construct more efficient trees. In order to evaluate the performance of our fast join mechanism, we measure the metrics such as the search latency and the number of searched node and the number of switching by the number of members and degree limit. The simulation results show that the performance of our mechanism is superior to that of the existing mechanism.

• Sleep Medicine and Psychophysiology
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• v.26 no.1
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• pp.44-48
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• 2019

Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

• The Journal of Korean Academy of Sensory Integration
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• v.18 no.3
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• pp.14-26
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• 2020

Objective : The purpose of this study was to investigate the effect of therapeutic listening on task performance, auditory behavior problems, and attention in children with sensory modulation disorder. Methods : Sixteen children aged four to seven years who were classified as children with sensory modulation disorder were randomly assigned to either the experimental group (n = 8) or the control group (n = 8). From July 1 to October 18, 2017, both groups participated in sensory integration programs, while therapeutic listening training was administered only to the experimental group. Sensory integration therapy was conducted in two sessions per week for six weeks (12 sessions); each session consisted of 40 minutes of therapy and 10 minutes of parent education. Therapeutic listening was conducted in three thirty-minute sessions per week for six weeks (18 sessions). We used the Canadian Occupation Performance Measure (COPM) to evaluate changes in the participants' occupational performance between pre- and post-intervention. We used Fisher's Auditory Problems Checklist (FAPC) to observe changes in behavioral problems related to hearing. The Child Attention Scale for Teacher (CAST) was used to evaluate changes in attention. Results : No significant differences pre- and post-intervention between the two groups were observed. The participants' auditory behavioral problems improved significantly in the experimental group, but no significant difference was found between the two groups. There was no significant difference in attention between the two groups, but there was a significant difference between the two groups in the "adaptability" and "emotion" domains (p < .05). Conclusion : The results suggest that therapeutic listening training has a positive effect on reducing problematic behaviors related to hearing and improving the occupational performance of children with sensory modulation disorder. This study provides a basis for improving the sensory processing ability of children with sensory modulation disorder by applying listening training in the clinical field and at home.

• Food Science and Industry
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• v.55 no.2
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• pp.188-202
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• 2022

In the insect industry, as the scope of application of insects is expanded from pet insects and natural enemies to feed, edible and medicinal insects, the demand for quality control of insect raw materials is increasing, and interest in securing the safety of insect products is increasing. In the process of expanding the industrial scale, controlling the temperature and humidity and air quality in the insect breeding room and preventing the spread of pathogens and other pollutants are important success factors. It requires a controlled environment under the operating system. European commercial insect breeding facilities have attracted considerable investor interest, and insect companies are building large-scale production facilities, which became possible after the EU approved the use of insect protein as feedstock for fish farming in July 2017. Other fields, such as food and medicine, have also accelerated the application of cutting-edge technology. In the future, the global insect industry will purchase eggs or small larvae from suppliers and a system that focuses on the larval fattening, i.e., production raw material, until the insects mature, and a system that handles the entire production process from egg laying, harvesting, and initial pre-treatment of larvae., increasingly subdivided into large-scale production systems that cover all stages of insect larvae production and further processing steps such as milling, fat removal and protein or fat fractionation. In Korea, research and development of insect smart factory farms using artificial intelligence and ICT is accelerating, so insects can be used as carbon-free materials in secondary industries such as natural plastics or natural molding materials as well as existing feed and food. A Korean-style customized breeding system for shortening the breeding period or enhancing functionality is expected to be developed soon.

• Resources Recycling
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• v.32 no.1
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• pp.50-59
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• 2023

The amount of dust generated during the dissolution of scrap in an electric arc furnace is approximately 1.5% of the scrap metal input, and it is primarily collected in a bag filter. Electric arc furnace dust primarily consists of zinc and ion. The processing of zinc starts with its conversion into pellet form by the addition of a carbon-based reducing agent(coke, anthracite) and limestone (C/S control). These pellets then undergo reduction, volatilization, and re-oxidation in rotary kiln or RHF reactor to recover crude zinc oxide (60%w/w). Next, iron is discharged from the electric arc furnace dust as a solid called Fe clinker (secondary by-product of the Fe-base). Several methods are then used to treat the Fe clinker, which vary depending on the country, including landfilling and recycling (e.g., subbase course material, aggregate for concrete, Fe-source for cement manufacturing). However, landfilling has several drawbacks, including environmental pollution due to leaching, high landfill costs, and wastage of iron resources. To improve Fe recovery in the clinker, we pulverized it into optimal -sized particles and employed specific gravity and magnetic force selection methods to isolate this metal. A carbon-based reducing agent and a binding material were added to the separated coarse powder (>10㎛) to prepare briquette clinker. A small amount (1-3%w/w) of the briquette clinker was charged with the scrap in an electric arc furnace to evaluate its feasibility as an additives (carbonaceous material, heat-generating material, and Fe source).