• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.1
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• pp.38-47
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• 2016

Objectives: The objective of this study was to determine the exposure levels of forklift operators to diesel engine exhaust(DEE) using black carbon(BC), elemental carbon(EC), and nitrogen dioxide($NO_2$) as indicators. Methods: A total of eight forklift operators in six collection companies were assessed over a period of two months from July to September 2015. BC was measured using a real-time monitor and respirable EC samples were analyzed using the NIOSH method 5040. $NO_2$ samples were collected using a passive badge-type sampler. Results: The geometric mean of BC, EC and $NO_2$ were $3.1-19.1{\mu}g/m^3$, $2.1-23.8{\mu}g/m^3$, and 12.5-166.6 ppb at all companies. When forklifts were operating both outside and inside, BC concentrations increased 2.0-5.6 times. The highest increase was observed when forklifts were operating indoors. The increase in BC concentrations varied by company(company A: 2.0 times, B: 3.2 times, C: 5.6 times, D: 2.1 times, E: 5.1 times, F: 2.6 times). The geometric mean of BC, EC, and $NO_2$ for the forklift operators was $9.6{\mu}g/m^3$, $7.9{\mu}g/m^3$, and 48.9 ppb, respectively. The geometric mean of BC, EC, and $NO_2$ for manufacturing workers was $9.3{\mu}g/m^3$, $0.9{\mu}g/m^3$, and 85.2 ppb, respectively. The mean BC and EC exposure levels for the forklift operators were slightly higher than those for manufacturing workers, but $NO_2$ levels for manufacturing workers were higher than those for the forklift operators(p>0.05). Multiple regression analysis revealed that diesel exhaust emissions standard, forklift weight and forklift manufacturer were the most influential factors in determining worker exposure. Conclusions: In the DEE work environment, workers who perform tasks within the workplace as well as inside forklifts as operators are likely to be exposed to a lack of ventilation. Further study of forklift operators' exposure to DEE indicators should be conducted to include a wider range of occupational and environmental situations, such as collection procedures, seasonal situations, types of fuel used, and number of forklifts.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.188-198
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• 2005

This study was conducted to survey the catches of vertical bottom longline fisheries in the sea mount of central northern Pacific($30^{\circ}-42^{\circ}N$, $170^{\circ}-175^{\circ}E$), during the period of July 1 to August 25,2004 by commercial fishing vessel. The number of 57 test fishing was carried out in the central northern Pacific during 43 days and the total catches were 21,092.4kg as 19 fish species, CPUE/day and catches/day were 185 baskets and 490.5kg, respectively. Main fish species caught from the experimental fishing were Squalus mitsukurii (66.3%), Coelorhyrchus asperocephaius (11.7%) and Helicolenus avius (9.8%) and, average inside diameter for fish mouth was 4.0cm over. Catch ratio according to each fishing ground was the order of F, D, J, B and C. Catch ratio fur water depth was the order of 450-500m, 350-400m, 300-350m, 400-450m, 1000-1100m and 500-550m and, main species by water depth was Squalus mitsukurii for 300-400m, Etmopterus lucifer for 300-550m, Coelorhyrchus asperocephaius far 1,000m over. Catch ratio according to the kind of hooks was higher at the hook no.6 for Squalus mitsukurii and no. 5 for Etmopterus lucifer and, catch ratio by baits was higher at squid for Squalus mitsukurii, saury and eel for Helicolemus avius and saury for Etmopterus lucifer. Accordingly, it is thought that the extension of fishing hours is needed with the reduction of damage and loss for fishing gears during fishing operation.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.2 no.1
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• pp.77-79
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• 2002

The urea cycle, consisting of a series of six enzymatic reactions, plays key roles to prevent the accumulation of toxic nitrogenous compound and synthesize arginine de novo. Five well characterized diseases have been described, resulting from an enzymatic defect in the biosynthesis of one of the normally expressed enzyme. This presentation will focus on two representative diseases; ornithine transcarbamylase(OTC) deficiency and citrullinemia(argininosuccinate synthetase deficiency). OTC deficiency is one of the most common inborn error of urea cycle, which is inherited in X-linked manner. We identified 17 different mutations in 20 unrelated Korean patients with OTC deficiency; L9X, R26P, R26X, T44I, R92X, G100R, R141Q, G195R, M205T, H214Y, D249G, R277W, F281S, 853 del C, R320X, V323M and 10 bp del at nt. 796-805. These mutations occur at well conserved nucleotide sequences across species or CpG hot spot. The L9X and R26X lead to the disruption of leader sequences, required for directing mitochondrial localization of the OTC precursor. Their phenotypes are severe, and neonatal onset. The G100R, R277W and V323M mutations were uniquely identified in patients with late onset OTC deficiency. The other genotypes are associated with neonatal onset. Out of 20 patients with OTC deficiency, only 6 patients are alive; two were liver transplanted, and normal in growth and development at 2, 4 years after transplantation respectively. Citrullinemia is an autosomal recessive disease, caused by the mutations in the argininosuccinate synthetase(ASS) gene. We identified in 3 major mutations in 11 unrelated Korean patients with citrullinemia; G324S, $IVS6^{-2}$ A to G, and 67 bp ins at nt 1125-1126. Among these, the 67 base pair insertion mutation is novel. The allele frequency of each mutation is; G324S(45%), IVS6-2 A to G(32%), and 67 base pair insertion(14%). All patients are diagnosed at neonatal or infantile age. Interestingly, two patients presented with stroke like episode. Out of 11 patients, 5 patients died. Among 6 patients alive, one patient was successfully liver transplanted.

• Journal of the Korean Society for Library and Information Science
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• v.41 no.2
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• pp.161-180
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• 2007

The goal of this study is to examine what sort of books people read repeatedly, what are the different preferences between men and women, how much the repeatedly-read books are related to the most memorable books and how the repeatedly-read books are connected to reading habits. A questionnaire was provided to college students and their repeated reading experiences were searched. The results of the statistical analysis are summarized : 1) Most college students have experienced repeated reading more than twice. 2) The number of college students who have experienced repeated reading twice is the highest and next, those who have read repeatedly 3 times. Also, the number of times of repeated reading tends to be similar between male and female students. 3) The books which many students read repeatedly more than twice are : a) Romance of 3 Kingdoms b) Little Prince c) Da Vinci Code d) Alchemist e) Chinese nine spine stickle back f) Meu Pe do Larania Lima g) Harry potter. 4) About half of the students have read the most memorable books many times. 5) The importance of books was evaluated on the basis of the number of repeated readers and the number of readings. The order of the important books is Three Romans of 3 kingdoms, Little Prince, Da Vinci Code, Meu Pe do Larania Lima, Tuesdays with Mollie, Harry Potter, and The Myth of Greece and Rome. 6) The preferred books by male college students are mostly the stories of fighters while female likes books that contain deep emotion and morality. More than half of the males' repeated reading was Romance of 3 Kingdoms while the preferred books of females are distributed widely.

• Journal of Korean Physical Therapy Science
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• v.13 no.4
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• pp.43-62
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• 2006

The survey was conducted with participation of the 289 handicapped persons residing at the rural area OOeup-gun in Kyungbook for the period of March 2 - May 31, 2006, to study the nature in general of the handicapped and the boundaries of their need. For the nature in general of the handicapped, the study was done by gender iscrimination, age, marital status, religion, educational level, occupation, monthly income, disability cause, disabled duration, disability type, disability level. For the boundaries of their need, the study was done by demand of financial support, educational demand, demand of voluntary workers, need of rehabilitation and medical treatment, job training, improvement of living conditions, or so. Using the Win.SPSS program, we made a frequency analysis and conclusions on the nature in general of the handicapped and the boundaries of their need on a 2-test. Conclusions are : 1. Nature in general of the handicapped The existence of the handicapped shows high at the age over 51 (71.6%), male-handicapped (65.1%), primary school graduates (62.9%), farming engaging (65.2%), monthly income less than one million Won (80.5%), cause by disease (53.8%), duration more than 10 years (61.6%), disability at level 3 (39.8%), extremity disability (66.4%). 2. Correlation of nature in general with demand of the handicapped a. In demanding the financial support, support for helper’s compensation shows high (p<0.05). In demanding the necessity of voluntary workers, the male-handicapped appears high during the absence of family assistance and the female-handicapped appears differently per week and also appears high during the absence of family assistance (p<0.05). b. In educational demand of the handicapped by their age, the age below 30 demands technical-job training and the age over 31 demands medical education for health care (p<0.01). c. In demanding the financial support by educational level, support for living cost shows high (p<0.05). d. In demanding improvement of living conditions by postnatal cause of disability, improvement of house structure shows high (p<0.05). e. In demanding assistance of voluntary workers by disabled duration, "No Need" shows high in the disabled duration more than 4 years (p<0.05). f. In demanding rehabilitation and medical treatment by disability type, home-visiting treatment, oriental medical treatment and physical therapy show high (p<0.001). g. In educational demand by disability level, medical education for health care shows high (p<0.01).

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.212-218
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• 1983

The effect of dietary calcium and magnesium on the 3-Hydroxy-3-methyl-glutaryl coenzyme A reductase (E.C. 1.1.1.34) in rabbit's liver microsomal protein was studied for a period of 4 weeks using isocalories and isonitro-genous as a basal diet. The experimental rabbits fed the following basal diets, such as crude protein 68.45%, carbohydrates 13.38%, fats 16.17% and added some sorts of calcium and magnesium, according to experimental plan making. The subject rabbits were divided into 9 feeding groups. The results are summarized as follows. Body weight gains per week of the groups fed magnesium and basal diet showed a little bit increase, but the groups fed calcium and basal diet showed a little bit decrease compare with control group. In case of serum magnesium, control group was 9.5mg% groups fed basal diet and magnesium were 8.27mg% in average, groups fed basal diet and calcium were 4.45mg% in average. In case of serum calcium, control group was 15.3mg%, groups fed basal diet and magnesium were 14.6mg% in average, groups fed basal diet and calcium were 14.1mg% in average. There was no great difference between magnesium fed groups in serum calcium. In serum triglyceride, control group was 82.8mg%, groups fed magnesium and basal diet were 60.3mg% in average, groups fed calcium and basal diet were 69.5mg% in average. The calcium fed groups were higher than the magnesium fed groups in serum triglyceride. In serum cholesterol, control group was 80mg%, groups fed magnesium and basal diet were 64.3mg% in average, groups fed calcium and basal diet were 56.3mg% in average. The calcium fed groups were lower than the magnesium fed groups in serum cholesterol. In case of the 3-Hydroxy-3-methylglutaryl coenzyme A reductase activity, control group was 0.998nmol/min/mg protein, groups fed magnesium and basal diet of HMG-CoA were 0.849nmol/min/mg in average.

• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.17-26
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• 1987

To develop the rehabilitation measures for rockily denuded forest lands which are widely distributed in Seoul metropolitan area, erosional characteristics of denudation should, first of all, be evaluated and analysed. As a fundamental study for developing such technical measures, the rockily denuded lands were classified into 6 types according to denudation features of the mountain land, and also movements of stone debris-and-sand on rock-exposed hillslopes were measured and analysed. The 6 basic types of denudation features include a) natural rock-outcrop-exposed land, b) stone debris-and-sand scattered land, c) stone debris-and-sand deposited land, d) coarse sand producing bare land susceptible to weathering and erosion, e) dwarfed pine growing land, and f) torrential valley susceptible to the debris slides. In the stone debris-and-sand scattered hillslopes (type b), average amount of moved-down debris reached to about 3.9 ton/ha/yr due to surface washing and slidings. In the particle size distribution of the moved-down debris, it amounts to about 25% of 10-25mm, about 15% of 5-10mm, about 24% of 2-5mm, and about 36% of less than 2mm in diameter class, respectively. The detailed experimental studies should be accomplished further more about the denudation processes including weathering, erosion and debris slides on rock-exposed hillslopes.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.3
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• pp.64-69
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• 2007

Motion control of the system is a position control of motor. Motion control of an uncertain robot system is considered as one of the most important and fundamental research directions in the robotics. Some distinguished works using linear control, adaptive control, robust control strategies based on computed torque methodology have been reported. However, it is generally recognized within the control community that these strategies suffer from the following problems : the exact robot dynamics are needed and hard to implement, the adaptive control cannot guarantee the performance during the transient period for adaptation under the variation, the robust control algorithms such as the sliding mode control need information on the bounds of the possible uncertainty and disturbance. And it produces a large control input as well. In this dissertation, a motion control for the unmanned intelligent robot system using disturbance observer is studied. This system is affected with an impact vibration disturbance. This paper describes a stable motion control of the system with the consideration of external disturbance. To obtain the stable motion independently against the external disturbance, the disturbance rejection is strongly required. To address the above issue, this paper presents a Disturbance OBserver(DOB) control algorithm. The validity of the suggested DOB robust control scheme is confirmed by several computer simulation results. And the experiments with a motor system is performed to give the validity of applicability in the industrial field. This results make the easier implementation of the controller possible in the field.

• Journal of the Korean earth science society
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• v.23 no.5
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• pp.397-405
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• 2002

This study investigated science gifted middle school students' philosophical views on scientific knowledge, and the effects of discussing and reading related to the knowledge. Ten eighth-graders in a science gifted class participated in this study. The results can be summarized as follows: 1, At the beginning, the students had one of six positions: (a) relativism (n = 2); (b) falsificationism (n = 2); (c) borderline between relativism and eclecticism (n = 1); (d) borderline between falsificationism and eclecticism (n = 3); (e) borderline among relativism, falsificationism, and eclecticism (n = 1); and (f) borderline inductivism and eclecticism (n = 1). This result indicated that most students had on almost modern philosophical view of scientific knowledge. 2, Some students, who had chosen the item of inductivism in some questions of the instrument at the beginning, maintained their selection despite discussions and readings related to scientific knowledge. The data were examples which indicated the difficulty of changing from a traditional view to a modern view of scientific knowledge.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1252-1258
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• 1998

Capillary electrophoresis (CE) with rice proteins was used to discriminate 10 domestic rice cultivars in less than 25 min. Most cultivars were differentiated quickly and easily using P-ACN buffer system. CE of rice prolamins allowed classifying ten varieties of Korean rice into three groups. Peak h was characteristic peak for Dongjinbyeo, Gaehwabyeo and Yongnambyeo which were classified into the group of Dongjinbyeo. Chuchungbyeo, Odaebyeo, Mangeumbyeo and Bonggwangbyeo easily differentiated from the group of Dongjinbyeo by the absence of peak h which were classified into the group of Chuchungbyeo. Peak g typical for Illpumbyeo, Hwaseungbyeo and Hwayoungbyeo accounted for 70% of total peak area. They belong to the group of Illpumbyeo. Some cultivars showed specific peak patterns among ten cultivars, Illpumbyeo was differentiated from others by several peaks between peak c and peak f, and the peak d was apparently detected in Odaebyeo not in others. Other minor differences were also found within each group. The result of the study showed that CE has potential for discrimination of rice cultivars. It also possesses the inherent advantages such as low mass requirements, fast seperations, and quantitative analysis through on-capillary UV detection.