• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.65-78
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• 2006

This paper investigates the cost structure ot the Korea and Japan railroad industry with respect to density, scale and scope economies as well as productivity growth rate using a generalized trans)og multiproduct cost function model. The paper then assumes that the Korea and Japan railway companies pi·educe three outputs (incumbent railway passenger-kilometers. Shinkansen passenger-kilometers, ton-kilometers of freight) using four input factors (labor, fuel, maintenance, rolling stock and capital). The specified cost function includes foul other independent variables: track lengths to reflect network effects, two dummies to reflect nation and ownership effects, and time trend as a proxy for technical change. The simultaneous equation system consisting of a cost function and three input share equations is estimated with the Zellner's iterative seemingly unrelated regression. The unbalanced panel data used in the paper, a total of 154 observations. are collected from the annual records of the Korea National Railroad (KNR) for the yews $1977{\sim}2003$, Japan National Railways (JNR) for the years $1977{\sim}1984$. seven Japan Railways (JR's) for the years $1987{\sim}2003$. The findings show that the Korean and Japanese railways exhibit product-specific and overall economies of density but product-specific diseconomies of scale with respect to incumbent railway passenger-kilometers, Shinkansen-kilometers and ton-kilometers. However, the railways experience mild overall economies of scale which result from economies of scope associated with the joint production of incumbent railway/Shinkansen and feight, freight/incumbent railway and Shinkansen except Shinkansen/incumbent railway and freight. In addition, the economies of density and scale in the KNR, JR east, JR central, and JR west companies at the point of the years $1990{\sim}2003$ average is generally analogous to the above results at the point of sample average. There also appear to be economies of ssope associated with the joint Production of the incumbent railway and Shinkansen in JR central but diseconomies of scope in JR East and JR West. The findings also indicate that the productivity growth rate of the privately-owned JR's is larger than that of the government-owned KNR.

• Journal of the Mineralogical Society of Korea
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• v.22 no.3
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• pp.229-240
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• 2009

In Gosung, the symptoms similar to itai-itai disease from neighboring residents of the Samsanjeil mine have been social issues. Therefore, various researches on the behavior of heavy metals of the tailings impoundment of 280,000 ton in the Samsanjeil mine are required. In this paper, mineralogical and geochemical studies on the tailings at different depths in the Samsanjeil mine were investigated and the factors on the behavior of heavy metals were also studied. At two sampling sites (NN and SN), samples were collected at different depths down to 1 m. At NN sites, pH values decreased with depth, while those at SN sites did not show significant changes. XRD analysis showed that the main minerals in the tailings were quartz, microcline, muscovite, and chlorite with minor amount of gypsum. There were no noticeable changes in the mineral composition with depth. At NN sites, the amount of calcite was negligible, and jarosite, which usually occurs at acid soil or acid mine drainage at pH lower than 4, was identified. However, the samples at SN site contained relatively high contents of calcite with pyrite. Therefore, calcite seemed to buffer the acid and control pH at SN site. The contents of heavy metals in tailings were in the order of Cu > As > Zn > Pb > Co > Cr > Ni > Cd. The heavy metal concentrations in the tailings were closely related with pH changes. The concentrations of Cd and Co were much lower at NN site at which pH values are low than those at SN sites. Contrary to that, Cr and As which exist as oxyanions showed higher concentrations at SN sites. This result showed that the behaviors of heavy metals in our study area were controlled by pH which is influenced by the contents of calcite.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.151-161
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• 2004

Three dimensional quantitative structure-activity relationships (3D-QSAR) studies for the protox inhibition activities against root and shoot of rice plant (Orysa sativa L.) and barnyardgrass (Echinochloa crus-galli) by a series of new A=3,4,5,6-tetrahydrophthalimino, B=3-chloro-4,5,6,7-tetrahydro-2H-indazolyl and C=3,4-dimethylmaleimino group, and R-group substituted on the phenyl ring in 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2chloro-4-fluorobenzene derivatives were performed using comparative molecular field analyses (CoMFA) methodology with Gasteiger-Huckel charge. Four CoMFA models for the protox inhibition activities against root and shoot of the two plants were generated using 46 molecules as training set and the predictive ability of the each models was evaluated against a test set of 8 molecules. And the statistical results of these models with combination (SIH) of standard field, indicator field and H-bond field showed the best predictability of the protox inhibition activities based on the cross-validated value $r^2_{cv.}$ $(q^2=0.635\sim0.924)$, conventional coefficient $(r^2_{ncv.}=0.928\sim0.977)$ and PRESS value $(0.091\sim0.156)$, respectively. The activities exhibited a strong correlation with steric $(74.3\sim87.4%)$, electrostatic $(10.10\sim18.5%)$ and hydrophobic $(1.10\sim8.30%)$ factors of the molecules. The steric feature of molecule may be an important factor for the activities. We founded that an novel selective and higher protox inhibitors between the two plants may be designed by modification of X-subsitutents for barnyardgrass based upon the results obtained from CoMFA analyses.

• Journal of Korean Home Economics Education Association
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• v.30 no.1
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• pp.43-63
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• 2018

The purpose of this study is to examine the various contexts affecting life culture through practical reasoning process and to select the goal and contents system of unification education in middle school home economics to form healthy unification community and to develop teaching and learning process. Based on the Unification Education Guidelines, Unification Education Pre-Study, Pre-Study on North Korean Defectors, and Analysis of the 2015 Revision Home Economics Curriculum in Korea, Goal and content system. Based on this, we developed a teaching and learning process and a student activity place applying practical reasoning process after extracting practical problems, and prepared a final development plan based on the results of two expert group evaluations. The results of this study are summarized as follows. First, the goal of unification education in the middle school home economics class is to 'Based on the social-cultural context, we develop the ability to cultivate healthy reunification by respecting the differences between the cultures of the two Koreas and discovering common values in a unified society and resolving practical issues in a unified society.'. Second, the content system of middle school home economics unification education was selected as the core theme of 'Unification Education Focused on the Living Culture'. The content elements were comprehending the socio - cultural context that affects the life culture of the two Koreas, Related language, maintenance of diversity of dietary culture in each region including North Korean food, social norms and attire, correct housing value and common living etiquette. Based on the goals of unification education in the middle school home school curriculum, we selected practical issues as 'What should we do to create a healthy unified community?'. Third, the teaching and learning process of unification education in junior high school home economics education is to recognize the problem of unification, to analyze the factors affecting the life culture of the two Koreas, to grasp the effect of the action and the ripple effects, to select alternative methods, And 4 subjects for 8 teaching learning course plan, and 35 teaching materials.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.11-22
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• 1985

Femur neck fracture is well known as one of the major death cause after trauma in elderly patients, and unsolved fracture due to its frequent association with complications such as avascular necrosis and nonunion. Through meticulous evaluation of the patient, hip and surgeon's experiences, reduction of mortality and morbidity as well as rapid recovery of the patient to the preinjury social and ambulatory status without local complications and revision after treatment is urgently needed. Many factors about this fracture In itself were noted, but we have analyzed 18 femur neck fractures of the patients older than 50 years preliminarily according to age, fracture pattern, osteoporosis, etiology and method of treatment with its delay in association with major complications especially avascular necrosis and nonunion. The results are as follows; 1. Of these 18 fractures, 11 were in females, 8 were caused by minor trauma such as slip-down accident and 4 were associated with definite osteoporosis according to the Sing's classification. 2. Fracture pattern of these 18 are undisplaced in 4, displaced subcapital in 11, displaced transcervical in 3. 11 fractures in the patients older than 60 year are composed of 3 undisplaced or impacted fractures and 8 displaced subcapital fractures. 3. These 18 fractures were treated by closed reduction and Internal fixation with multiple pins in 13, and hemiarthroplasty in 4, but one was not treated to die after discharge from hospital. 4. 4 undisplaced or impacted fractures and 3 displaced transcervical fractures were not associated with any complications such as avascular necrosis or nonunion. But 4 of 6 displaced subcapital fractures were complicated by avascular necrosis, 3 of which were reduced in the varus position within 1 week, and the other was reduced in the good position on 1 week after trauma. There was no complication in 2 displaced subcapital fractures reduced in valgus position within 3 days after trauma. According to the above results, the prognosis of the femur neck fracture is dependent upon the fracture pattern and delay in its treatment. So it is inevitable to reduce the fracture in anatomical or valgus position as early as possible. But the arthroplasty may be needed in displaced subcapital fractures delayed for several days, with its reluction in extreme varus position or impossible and with pre-existing disease in the same hip Joint (total hip replacement).

• Food Science and Preservation
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• v.22 no.1
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• pp.27-35
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• 2015

Anti-obese effects of mulberry (Morus alba L.) root bark was investigated in vitro by measuring its inhibitory effect against 3T3-L1 preadipocyte differentiation and digestive enzymes such as ${\alpha}$-amylase, ${\alpha}$-glucosidase and pancreatic lipase. Ethanol extract of mulberry root bark (MRE) showed the potent inhibitory activities on ${\alpha}$-amylase, ${\alpha}$-glucosidase and pancreatic lipase with $IC_{50}$ values of $7.86{\pm}0.36$, $0.12{\pm}0.03$ and $7.93{\pm}0.11mg/mL$, respectively. Furthermore, MRE significantly suppressed cellular lipid accumulation in 3T3-L1 cells in a dose-dependent manner. To elucidate the mechanism of MRE, we performed qRT-PCR and Western blotting for the expression of genes related with adipogenesis and lipogenesis. Treatment of MRE markedly suppressed the protein expression of $PPAR{\gamma}$, $C/EBP{\alpha}$ and SREBP-1c, as well as FAS and ACC, which are the key transcription factors and metabolic enzymes in adipogenesis and lipogenesis. In addition, qRT-PCR analysis indicated that the anti-adipogenesis effect of MRE might be due to its inhibition at transcription levels. These results demonstrate that MRE can effectively suppress adipocyte differentiation and inhibit key enzymes related to obesity. Our findings suggest that mulberry root bark may have a potential benefit in preventing obesity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1482-1491
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• 2013

The purpose of this study was to investigate the safety accidents and physical fatigues of school foodservice employees. Out of 300 questionnaires distributed from December 1~20, 2011, 276 responded. After excluding 54 incomplete questionnaires, 222 (usage rate: 74%) were examined in the final analysis. First, our results showed that in terms of safety accidents, most received bruises (92.8%), followed by burns (73.0%), cuts and lacerated wounds (69.4%), sprains (47.7%), falls (42.8%), fractures/dislocations (31.5%) and electric shock (2.7%). Second, we found that the average degree of physical fatigue of school foodservice employees was 3.65 based on the 5-point Likert scale. Specifically, pain in the arms and wrist was rated the highest, at 4.18. Third, results showed that the factors affecting physical fatigue were 'class of school' (P<0.05), 'frequency of meal serving per day' (P<0.05), 'no. of meals served per day' (P<0.001), 'no. of meals per employee' (P<0.05) and 'warm-up exercise before starting work' (P<0.05). This means that foodservice employees serving middle schools, serving meals three times per day, serving more than 1,000 meals per day, and serving more than 111 meals per employee perceive higher levels of physical fatigue. In addition, the physical fatigue of those who perform warm-up exercises before starting work was significantly lower than those who do not perform warm-up exercises before work (P<0.05). In conclusion, the frequently occurring major safety accidents of school foodservice employees were bruises and burns. An increase in workload also leads to the increasing physical fatigue of school foodservice employees. Thus, to lower the physical fatigue of school foodservice employees, school foodservice employees should be encouraged to perform warm-up exercises before staring work and new staffing guidelines for school foodservice employees should be developed.

• Applied Biological Chemistry
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• v.11
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• pp.173-184
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• 1969

To elucidate the effect of Amo-1618(4-hydroxyl-5-isopropyl-2-methlphenyl trimethyl ammonium chloride, 1-piperidine carboxylate) known as a kind of growth retardant, on the growth, grain yield, increasing the efficiency of nitrogen fertilizer, behavior of mineral nutritions and the rate of phosphorus utilization, this experiment was conducted pot culture method in a vinyl house. Two nitrogen level, namely, practical nitrogen level(1 N) and three times nitrogen level(3 N) was made and labelled double-calcium-superphosphate $Ca(H_2P^{32}O_4)_2.\;2H_2O)$ as a source of radioactive phosphorus(P-32) was employed $80\;{\mu}c/pot$, respectively. Rice seedlings, variety 'Suwon No. 82', was transplanted to a 1/50,000 a china pot on June 13 in 1968. For treatment, at early stage of tillering, 10,000 ppm solution of Amo-1618 was foliar sprayed only one time. The Duncan's new mutiple-range test was adopted for statistical analysis evaluating experimental data at 5% level significance. The results obtained may be summarized as follows; 1) No significant difference was found among the treatments in plant height, but in plot of Amo-1618 treatment and 3 N level, number of tillers was significantly increased than that of others. 2) Weight of 10,000 kernels and seed-setting rate was also remarkably increased in same treatment above. 3) Grain yield per pot was significantly increased in Amo-1618 and 3 N level application. This results seemed to be due to the increased the factors on the yield. 4) Contents of nitrogen and phosphorus per cent in the grain was likewise increased in Amo-1618 and 3 N application. There is, however, no difference among treatments in the content of nitrogen and phosphorus in the leaves and culms of rice plants. 5) On the other hand, the contents of potassium and magnesium, no distinctly tendeny showed among treatments. 6) The rate of phosphorus utilization was significantly increased in the plot of Amo-1618 and 3 N application.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.80-88
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• 2013

Carrot (Daucus carota L. var. sativa) is one of the most extensively used vegetable crops in the world and a significant source of nutrient because of its high content of ${\beta}$-carotene, well known as the precursor of vitamin A carotenoid. However, seed-hairs generated and elongated from the epidermal cell of seeds inhibit absorption and germination by various factors such as carotol and so on. Accordingly, mechanical hair removal process is essential before commercialization of carrot seeds. Because of this process, producers will have additional losses such as time consuming, manpower, capital and so on. Furthermore, physical damage of seeds causes irregular germination rate. To overcome such cumbersome weaknesses, new breeding program for developing hairless-seed carrot cultivar has been needed and studies for molecular markers related to seed-hair characteristic is needed for a new breeding program. Therefore, in this study, cDNA libraries from seeds of short-hair seed phenotype CT-SMR 616 OP 659-1 line, hairy-seed phenotype CT-SMR 616 OP 677-14 line and short-hair seed phenotype CT-ATR 615 OP 666-13 line, hairy-seed phenotype CT-ATR 615 OP 671-9 were constructed, respectively. Furthermore, 1,248 ESTs in each line, total 4,992 ESTs were sequenced. As a result, 19 SNP sites and 14 SNP sites in each of 2 combinations were confirmed by analyzing these EST sequences from short-hair and hairy-seed lines. Then we designed SNP primer sets from EST sequences of SNP sites for high resolution melting (HRM) analysis. Designed HRM primers were analyzed using hairy seed phenotype CT-SMR 616 OP 1040 line and short-hair seed phenotype CT-SMR 616 OP 1024, 1025, 1026 lines. One set of HRM primers showed specific difference between the melting curves of hairy and short-hair seed phenotype lines. Based on this result, allele-specific (AS) PCR primers were designed for easier selection between hairy-seed carrot and hairless seed carrot. These results of HRM and AS-PCR are expected to be useful in breeding of hairless seed carrot cultivar as a molecular marker.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.43-54
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• 2001

Genetic differentiation of populations is resulted from the environmental and the genetic effects, and the interactions between them. Whereas, the major factors influencing to the genetic differentiation within populations are the gene flow induced by seed or pollen dispersial, the microsite heterogeneity, and the density-dependent distribution of individuals. For the purpose of studying spatial genetic structure and the distribution pattern of Korean pines(Pinus koraiensis), we set up one $100{\times}100m$ plot at a Korean pine stand in Quercus mongolica community on Mt. Jumbong in Korea. To estimate the coefficient of spatial autocorrelation as Moran's index and an analogue, simple block distance, isozyme markers were analyzed in 325 Korean pines. For 11 polymorphic loci observed in 9 enzyme systems, the average percentage of polymorphic loci, the observed and expected heterozygocity were 72.2% 0.200, and 0.251, respectively. It was revealed the excess of homozygotes was observed in the plot, which suggests that here may be more number of consanguineous trees than expected. On the basis of isozyme genotypes observed in this study, 325 trees were classified into 147 groups in which the maximum number of trees for one group was 34. From the distance class of 24-32m, the genetic heterogeneity began to increase. The variation of simple block distance against the growth performance by tree height and diameter also showed the same trend at 24~32m class. According to high fixation index(F=0.204), the spatial genetic structure within a stand, the analysis of the growth performance, and the distribution patterns of identical genotypes, we inferred that the genetic structure of a Korean pine stand in Mt. Jumbong has been maintained rather density-dependent mechanism than the gene flow, such as the pollen dispersial or the heavy input of seeds following the forest gaps. The genetic patchy size was determined between 24~32m, which suggests that the selection of individuals for the ex situ conservation of Korean pine in Mt. Jumbong may be desirable to be made with the spatial distance over 37 meters between trees.