• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1146-1152
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• 2005

Graft copolymers were synthesized from methylcellulose(MC) and acrylic acid(AA) with active carboxyl groups in the presence of potassium persulfate($K_2S_2O_8$) initiator to enhance adsorption capacity of toxic heavy metal such as $Pb^{2+}$ and $Cu^{2+}$ from wastewater. The resulting grafted copolymers(MC-g-AA/PAA) were mixture of the graft copolymers from MC and AA(MC-g-AA) and polyacrylic acid homopolymers(PAA). The degree of palling was increased with rising concentration of monomer and initiator under the reaction conditions at $60^{\circ}C$, 3 hrs. The water insoluble property of MC-g-AA showed more than 19.7% degree of grafting. So that it could be an adsorbent of heavy metals. Adsorption characteristics of the MC-g-AA were evaluated depending on the degree of grading, pH of wastewater, adsorption time, dosage of MC-g-AA and concentration of heavy metals in the different conditions. Degree of grafting, and initial concentration of heavy metal ions increased, the adsorption amount of $Pb^{2+}$ and $Cu^{2+}$ increased, but added MC-g-AA increased, the adsorption amount per unit weight of $Pb^{2+}$ and $Cu^{2+}$ decreased. The MC-g-AA showed the high $Pb^{2+}$ and $Cu^{2+}$ adsorption amount in the range pH $4{\sim}6$. Also all of $Pb^{2+}$ and $Cu^{2+}$ ions reached in adsorption equilibrium in neighborhood 4 hours. The adsorption of heavy metals described by Freundlich isotherm, it was determined the value of l/n of $Pb^{2+}$ and $Cu^{2+}$ that 0.4294 and 0.3453, respectively.

• Clinical and Experimental Pediatrics
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• v.57 no.12
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• pp.520-525
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• 2014

Purpose: Childhood obesity is an increasing public health issue worldwide. We examined dietary patterns among adolescents in a dormitory school, identified obese adolescents and tried to intervene to improve food habits and physical activity. Methods: We conducted an experimental prospective longitudinal study based on 36 obese (body mass index $[BMI]{\geq}95th$ percentile) adolescents (aged 12-18 years) compared with controls (healthy children: normal age-appropriate BMI ($BMI{\leq}85th$ percentile). Six months' intervention included lifestyle-modification counseling (once a week by a clinical dietician), and an exercise regimen twice a week, 60 minutes each time, instructed by a professional pediatric trainer). Both groups underwent baseline measurements at the beginning of the study and 6 months later (arterial stiffness, blood pressure, pulse, weight and height, hemoglobin, creatinine, liver enzymes, highly sensitive C-reactive protein and complete lipid profile). Results: Twenty-one participants completed the study. Low compliance from participants, school staff and parents was observed (participation in planned meetings; 71%-83%). BMI significantly decreased from $32.46{\pm}3.93kg/m^2$ to $30.32{\pm}3.4kg/m^2$ (P=0.002) in the study group. Arterial stiffness was not significantly different between the 2 groups and did not change significantly after 6 months' intervention (P=0.494). No significant changes in CRP and lipid profile were observed after the intervention. Conclusion: Making lifestyle modifications among adolescents in a dormitory school is a complex task. Active intervention indeed ameliorates BMI parameters. However, in order to maximize the beneficial effects, a multidisciplinary well-trained team is needed, with emphasis on integrating parents and the school environment.

• Journal of the Korean Arthroscopy Society
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• v.3 no.2
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• pp.91-96
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• 1999

Purpose : The purpose of this study is to compare the clinical and radiologic results of the anterior cruciate ligament(ACL) reconstruction using bone-patellar tendon-bone unit with doubled semitendinosus and gracilis tendons. Materias and Methods : Clinical results of ACL reconstructions which were performed in 47 patients using doubled semitendinosus and gracilis were compared with those performed in 45 patients using bone-patellar tendon-bone autograft. There were no differences in preoperative parameters(age, sex, instability). Average follow-up period were 17 months and 19 months each. Results : There were no significant differences between two groups in functional results (Lysholm knee score), degree of laxity and range of motion at final follow-up. However, the parapatellar complication, especially anterior knee pain after long distance walking or exercise and quadriceps weakness less occurred in hamstring tendon group than in bone-patellar tendon-bone group. Conclusion : Although there were no significant differences in clinical results of ACL reconstruction using bone-patellar tendon-bone autograft and doubled semitendinosus and gacilis, parapateller complications occurred more in the bone-patellar tendon-bone autograft group than in the doubled semitendinosus and gracilis group. It is thought that the careful selection of patient, achivement of skillful technique and active rehabilitation are important to prevent the parapatellar complications.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.1
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• pp.29-48
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• 2014

The recent keyword advertising does not reflect the individual customer searching pattern because it is focused on each keyword at the aggregate level. The purpose of this research is to observe processes of customer searching patterns. To be specific, individual deal-proneness is mainly concerned. This study incorporates location as a control variable. This paper examines the relationship between customers' searching patterns and probability of purchase. A customer searching session, which is the collection of sequence of keyword queries, is utilized as the unit of analysis. The degree of deal-proneness is measured using customer behavior which is revealed by customer searching keywords in the session. Deal-proneness measuring function calculates the discount of deal prone keyword leverage in accordance with customer searching order. Location searching specificity function is also calculated by the same logic. The analyzed data is narrowed down to the customer query session which has more than two keyword queries. The number of the data is 218,305 by session, which is derived from Internet advertising agency's (COMAS) advertisement managing data and the travel business advertisement revenue data from advertiser's. As a research result, there are three types of the deal-prone customer. At first, there is an unconditional active deal-proneness customer. It is the customer who has lower deal-proneness which means that he/she utilizes deal-prone keywords in the last phase. He/she starts searching a keyword like general ones and then finally purchased appropriate products by utilizing deal-prone keywords in the last time. Those two types of customers have the similar rates of purchase. However, the last type of the customer has middle deal-proneness; who utilizes deal-prone keywords in the middle of the process. This type of a customer closely gets into the information by employing deal-prone keywords but he/she could not find out appropriate alternative then would modify other keywords to look for other alternatives. That is the reason why the purchase probability in this case would be decreased Also, this research confirmed that there is a loyalty effect using location searching specificity. The customer who has higher trip loyalty for specificity location responds to selected promotion rather than general promotion. So, this customer has a lower probability to purchase.

• The Korean Journal of Pesticide Science
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• v.7 no.4
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• pp.258-263
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• 2003

In order to get the actual pesticide usage data for fruit crops at farmer's gate, this survey was carried out on the growers of 6 representative fruit crops such as apple, citrus, grape, peach, pear and persimmon, in Korea. One hundred fifty farmers were selected in main production areas to record their pesticide usage during the growing seasons. Pesticides were sprayed in pear 15.2 times/year and persimmon 7 times/year. Pesticide input amount per unit for fruits was 39.5 for citrus, 22.1 for apple, 21.5 for pear, 11.9 for peach, 10.8 for persimmon and 6.7 a.i. kg/ha for grape, respectively. The amounts of pesticides sprayed in 2002 except for peach and pear tend to decrease compared with those in 1999. The major fungicides used were mancozeb, propineb, dithianon, etc., while the major insecticides were fenitrothion, chlorpyrifos, methidathion, etc. Total active ingredients of pesticides used for six fruit crops amounted to 18.3% of total sales amount of pesticides for horticulture in 2002. The amounts of pesticides sprayed on citrus, grape, peach and pear in Korea was less than those in U.S.A., excepting those in apple.

• Korean Journal of Cognitive Science
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• v.12 no.3
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• pp.1-18
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• 2001

The goal of this paper is the pedagogical application of a Korean Spell/Grammar Checker to the web-based language learning system for Korean writing. To maximize the efficient instruction of our learning system \\`Urimal Baeumteo\\` we have to improve our Korean Spell/Grammar Checker. Today the NLP system\\`s performance defends on its semantic processing capability. In our Korean Spell/Grammar Checker. the tasks accomplished in the semantic level are: the detection and correction of misused derived and compound nouns in a Korean spell-checking device and the detection and correction of syntactic and semantic errors in a Korean grammars-checking device. We describe a common approach to the partial parsing using collocation rules based on the dependency grammar. To provide more detailed semantic rules. we classified nouns according to their concepts. and subcategorized verbs referring to their syntactic and semantic features. Improving a Korean Spell/Gl-Grammar Checker makes our learning system active and intelligent in a web-based environment. We acknowledge the flaws in our system: the classification of nouns based on their meanings and concepts is a time consuming task. the analytic unit of this study is principally limited to the phrases in a sentence therefore the accurate parsing of embedded sentences remains a difficult problem to solve. Concerning the web-based language learning system. it is critically important to consider its interface design and structure of its contents.

• The Korean Nurse
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• v.36 no.4
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• pp.61-74
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• 1997

This study is a descriptive study which was done to examine the circumstances surrounding burn accidents in children in order to develop a burn prevention program. The subjects for the study were the mothers of 107 children admitted to two burn specialty hospitals in seoul and the mothers of 172 healthy children attending day care or kindergarten. The tool used in the study was developed by the researchers, pretested and refined. Cronbach's alpha was 0.72. Data collection was done between November 1995 and April 1996. Statistically analysis was done using SAS Version 6.04 and the data was analyzed using test, chi square, regression and logistic analysis. A suumary of the results shows the following : Eighty percent of the children in both groups lived in nuclear families but comparatively more of the children with burn accidents lived in apartments. More of the parents in the group of healthy children had university education and held white collar or professional jobs, while the parents of the children with burn accidents were slightly younger than the parents of the healthy children. but not significantly younger. A significantly greater number of families of children with burn accidents had more than one child and the characteristics of the children with burn accidents that they were more frequently boys, either first or last born and very active. Most of the burn accidents occurred in fall or winter. sometime between noon and midnight and the majority occurred in the home and were caused by hot liquid. In 86% of the cases emergency care was not given at home but the child was brought to the hospital emergency unit. Most of the burns were second degree or greater. involved the arms or legs. required admission, and 41.5% occurred when the parents were preparing or eating meals. In a test of knowledge of preventive measures, the mothers of children who had suffered burn accidents scored slightly higher than the mothers who had no experience with burn accidents, but this was not statistically significant. As to what to do in the case of a fire, the mothers of the healthy children had more knowledge about who to notify. but 70% of the mothers in both groups did not know how to escape from the house if it was of fire. 80 to 96% did not know what do to in case of a fire, such as rolling if clothes were on fire. 80% did not know what emergency care to give for a burn, and 74 to 87% did not know when it is appropriate to try to put out a fire. It can be concluded from this study that. since the results show that the most frequent situation which resulted in burn accidents was when the parents were not aware of the danger of burns or were not paying attention to the child. and when there were no protective devices to prevent burns. and that accidents most frequently occurred at home. the most effective way of preventing accidents is to develop in the parents a "safety mind", Since burn accidents in children are usually more severe than in adults. the physical. emotional. psychological and social damage is greater. In order to develop and awareness of this in the general public. the use of mass media. books and pamphlets and other educational media that provide education on prevention of burn accidents need to be utilized.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.580-586
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• 1989

Penicillium sp. CB-20 was selected for strong polygalacturonase activity among various strains of molds found in soil. The optimum pH for the enzyme activity was 5.0 and optimum temperature was 4$0^{\circ}C$. The enzyme was relatively stable in acidic condition and unstable by heat treatment. The activation energy, Km and V$_{max}$ for the polygalacturonase were 2.499 Kcal/mol, 2.13$\times$10$^{-2}$mol/l, and 104.17 $\mu$mol/min. The activity of polygalacturonase was inhibited by Ag$^{+}$, Cu$^{++}$, Pb$^{++}$, Fe$^{+++}$, $Ca^{++}$, Na$^+$, Mn$^{++}$. The enzyme can be inactivated by the treatment ethylenediamintetra acetic acid, 2,4-dinitrophenol and $H_2O$$_2$. The results indicate the possible involvement of histidine, chelate and terminal amino group as active site. The enzyme was endo-type polygalacturonase.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.194-200
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• 2011

Diamondback moth (DBM, Plutella xylostella L.) is known as the most destructive pest of cruciferous crops worldwide. As most insecticides targeted to mainly larval stage, new insecticides which have hatching-inhibitory or ovicidal activity could be more efficient to control DBM. Therefore, we developed an easy and efficient method for screening ovicidal activity of DBM eggs using aluminum foil. The aluminum foil ($4{\times}12$ cm) coated with filtered juice of chinese cabbage leave (hereinafter called oviposition foil) exposed to 300 newly-emerged adults for 24 hours inside the rearing container. The oviposition foils were replaced every 4 days consecutively after mating, but it was better to discarded over then. Oviposition foil were divided into 6 to 12 pieces depending on egg mass volume. After dipping into test solutions for 10 seconds using faucet, oviposition foil pieces were placed into common petri dish, and then investigated hatchability. The effect of methanol solvent (50%) for 10 seconds dipping on the toxicity against DBM eggs was negligible. In addition, whether covering the petri dish or not should be dependent on nature of active compounds tested. With applying the new bioassay method, methanol extracts from 50 plants were tested the ovicidal activity to DBM eggs. Among them, four plant extracts; Angelica tenuissima root, Lycium chinense root, Cnidium officinale root and Polygala tenuifolia root, showed high ovicidal activity of over 90% control efficacy, against DBM eggs.

• Journal of dental hygiene science
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• v.10 no.2
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• pp.95-100
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• 2010

The purposes of this study were to examine the effect of different fluoridated bleaching solution on the changes in physical and chemical characteristics of tooth. Forty-eight bovine incisors were divided into four groups to receive bleaching treatments, over a 14days period, as follows: no treatment; 10% carbamide peroxide (CP) bleaching; 10% CP containing 0.05% fluoride; and 10% CP containing 0.1% fluoride. All the specimens were highly polished and discolored with commercial COCK.Color and enamel changes were determined with colorimeter, microhardness tester, scanning electron microscope, atomic force microscopy. All the collected data were analyzed with one-way ANOVA. After the bleaching, bleached groups showed the color change(E*). Microhardness of 10% CP group decreased after tooth bleaching. But microhardness of containing fluoride bleached groups increased after tooth bleaching. Enamel surface of 10% CP bleached group showed any apparent morphology and roughness changes compared to the enamel which was stored in distilled water only. These results demonstrated that Fluoridated 10% Carbamide Peroxide have appreciable bleaching effect on bovine teeth and were not adversely affects enamel. Supporting influence of fluoride-containing bleaching solution on remineralization could be observed and further research must be carried out in various active environments to confirm these results clinically.