• International Commerce and Information Review
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• v.10 no.4
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• pp.301-319
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• 2008

The development of Korea in the Northeast through trade is not a matter of choice as far as national strategy is concerned, but is an important national policy that is a matter of life or death which will determine the future fate of Korea. This thesis will attempt to arrive at a general, tangible plan for the development of Korea in the Northeast centered around trade by examining the change in naval environment at home and abroad, the given economic situation in the Northeast, and the present state of essential port development in Korea-China-Japan. Its objective will be to provide strategies for the development of Busan port confrontation. For the last ten years, China has been growing at a rapid rate. Since a lot of the volume of naval trade is being transferred from Korea to China, we must do everything we can to improve the service and reduce cost. In addition, Japan also is losing international position. Japan's government and the private industry are trying to make Super Core Ports a prominent feature of their port system. If the Busan port system is to remain competitive, these aspects of the Japanese port system must be kept in mind to prevent trade from going to other ports with more competitive systems.

• Animal Bioscience
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• v.35 no.7
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• pp.1021-1029
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• 2022

Objective: The study was aimed to investigate the rules of postprandial changes in intestine digesta dry matter (DM) flow and amino acid digestibility of growing pigs fed low-protein (LP) diets made of different starch. Methods: Eight barrows (28.8±2.1 kg) with a T-cannula at the distal ileum were randomly allotted to an 8×3 Youden square design. Treatments included: waxy corn starch LP (WLP); corn starch LP (CLP) and pea starch LP (PLP). Diets were given at 08:00 and 20:00. Digesta samples were collected in six 2-h stages from 08:00 to 20:00. Results: The Cr concentrations of ileal digesta increased and then decreased in WLP and CLP, while increased continuously in PLP as time passed after postprandial (p<0.05). Higher average Cr concentrations (0.78% and 0.84% vs 0.70%; p<0.05) and lower average DM flow (181.1 g/kg and 166.3 g/kg vs 240.3 g/kg; p<0.001) were observed in WLP and CLP, compared with PLP. The apparent ileal digestibility coefficient of most amino acids in WLP and CLP increased compared with that in PLP. No difference in lysine or methionine digestibility was observed. When digesta were collected in 2-h periods, the apparent ileal digestibility coefficient of amino acids did not change over time. When digesta was collected in 4-h periods from 16:00 to 20:00 and 6-h periods from 14:00 to 20:00 (p<0.05), WLP and CLP showed markedly higher amino acid digestibility than PLP Conclusion: High-amylose slowly digested starch can increase the DM flow at the distal ileum and reduce the apparent ileal digestibility coefficient of amino acids of pigs fed LP diets. Compared with waxy corn starch and corn starch, pea starch reduced the digestibility of amino acids in digesta collected after 4 h postprandial.

• Journal of The Korean Association For Science Education
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• v.27 no.4
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• pp.337-345
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• 2007

The purposes of this study are to investigate and compare the characteristics of classification criteria of secondary school students and science teachers in relation to the three statesof matter. For this research, 76 middle school students in the7th grade who studied microscopic viewpoints about classifying the state of matter for the first time, 69 high school students in the 12th grade who studied Chemistry I and IIcourses successfully, and 130 secondary school science teachers, through a questionnaire. As a result, while having learned the three states of matter in the microscopic viewpoints, the majority of middle school students showed a high percentage of classification in the macroscopic viewpoints. For high school students, their percentage of classification included highmicroscopic viewpoints about solid and gas, the percentage of classification included macroscopic viewpoints about liquid state as alsohigh. The secondary school teachers gave answers in the macroscopic viewpoints and microscopic viewpoints equally, but their answers were just representation of the viewpoints list without the meaningful connection of the two type of viewpoints. To solve these problems, It is necessary to form connective change from the macroscopic viewpoints to the microscopic viewpoints about the criteria for classifying the States of Matter and various educational efforts.

• Psychiatry investigation
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• v.15 no.12
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• pp.1162-1167
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• 2018

Objective Motor, perceptual, and cognitive functions are known to affect driving competence. Subcortical ischemic changes on brain magnetic resonance imaging (MRI) can reflect reduction in cognitive and motor performance. However, few studies have reported the relationship between subcortical ischemic changes and driving competence of the elderly. Thus, the objective of this study was to investigate the association between subcortical ischemic changes on MRI and driving abilities of the elderly. Methods Participants (n=540) were drawn from a nationwide, multicenter, hospital-based, longitudinal cohort. Each participant underwent MRI scan and interview for driving capacity categorized into 'now driving' and 'driving cessation (driven before, not driving now)'. Participants were divided into three groups (mild, n=389; moderate, n=116; and severe, n=35) depending on the degree of white matter hyperintensity (WMH) on MRI at baseline. Driving status was evaluated at follow-up. Statistical analyses were conducted using ${\chi}^2$ test, analysis of variance (ANOVA), structured equation model (SEM), and generalized estimating equation (GEE). Results In SEM, greater baseline degree of WMH was directly associated with driving cessation regardless of cognitive or motor dysfunction (${\beta}=-0.110$, p<0.001). In GEE models after controlling for age, sex, education, cognitive, and motor dysfunction, more severe change in the degree of WMH was associated with faster change from 'now driving' state to 'driving cessation' state over time in the elderly (${\beta}=-0.508$, p<0.001). Conclusion In both cross-sectional and longitudinal results, the degree of subcortical ischemic change on MRI might predict driving cessation in the elderly.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.3
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• pp.357-365
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• 2019

Objective: The experiment was conducted to evaluate the effects of four fungal pretreatments on the nutritional value of Camellia seed residues, and to evaluate the feeding value of pretreated Camellia seed residues for ruminants. Methods: Camellia seed residues were firstly fermented by four lignin degrading fungi, namely, Phanerochaete chrysosporium (P. chrysosporium)-30942, Trichoderma koningiopsis (T. koningiopsis)-2660, Trichoderma aspellum (T. aspellum)-2527, or T. aspellum-2627, under solid-state fermentation (SSF) conditions at six different incubation times. The nutritional value of each fermented Camellia seed residues was then analyzed. The fermentation profiles, organic matter degradability and metabolizable energy of each pre-treated Camellia seed residue were further evaluated using an in vitro rumen fermentation system. Results: After 5 days of fermentation, P. chrysosporium-30942 had higher degradation of lignin (20.51%), consumed less hemicellulose (4.02%), and the SSF efficiency reached 83.43%. T. koningiopsis-2660 degraded more lignin (21.54%) and consumed less cellulose (20.94%) and hemicellulose (2.51%), the SSF efficiency reached 127.93%. The maximum SSF efficiency was 58.18% for T. aspellum-2527 and 47.61% for T. aspellum-2627, appeared at 30 and 15 days respectively. All the fungal pretreatments significantly improved the crude protein content (p<0.05). The Camellia seed residues pretreated for 5 days were found to possess significantly increased organic matter degradability, volatile fatty acid production and metabolizable energy (p<0.05) after the treatment of either P. chrysosporium-30942, T. koningiopsis-2660 or T. aspellum-2527. The fungal pretreatments did not significantly change the rumen fermentation pattern of Camellia seed residues, with an unchanged ratio of acetate to propionate. Conclusion: The fungi showed excellent potential for the solid-state bioconversion of Camellia seed residues into digestible ruminant energy feed, and their shorter lignin degradation characteristics could reduce loss of the other available carbohydrates during SSF.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.627-636
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• 2020

Background: Cultivation of medicinal crops, which synthesize hundreds of substances for curative functions, was focused on the synthesis of secondary metabolites rather than biomass accumulation. Nutrition is an important restrict factor for plant growth and secondary metabolites, but little attention has been given to the plasticity of nutrient uptake and secondary metabolites synthesis response to soil nitrogen (N) change. Methods: Two year-field experiments of Sanqi (Panax notoginseng), which can synthesize a high level of saponin in cells, were conducted to study the effects of N application on the temporal dynamics of biomass, nutrient absorption, root architecture and the relationships between these parameters and saponin synthesis. Results: Increasing N fertilizer rates could improve the dry matter yields and nutrient absorption ability through increasing the maximum daily growth (or nutrient uptake) rate. Under suitable N level (225 kg/ha N), Sanqi restricted the root length and surface and enhanced the root diameter and N uptake rate per root length (NURI) to promote nutrient absorption, but the opposite status of Sanqi root architecture and NURI was found when soil N was deficient. Furthermore, increasing N rates could promote the accumulation of saponin in roots through improving the NURI, which showed a significant positive relationship with the content of saponin in the taproots. Conclusion: Appropriate N fertilizer rates could optimize both root architecture and nutrient uptake efficiency, then promote both the accumulation of dry matter and the synthesis of saponins.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.432-443
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• 2002

This study is to investigate the level of science learning concepts presented in life and matter fields of the 7th science textbooks. 6 units were analysed; 'the structure of living things', 'digestion and circulation' and 'respiration and excretion' of life field, and 'three states of matter', 'molecular motion', 'a change of state and the energy' of matter field. The gross number of concepts was 305 in life field, and 73 in matter field of the 7th science textbooks. Among publishing companies, the number of concepts was a little difference. Much more concepts in life field were presented than those in matter field. Percentages of the number of concrete and formal concepts were 58% and 42% in life, and 14% and 86% in matter field. The ratio of the number of concrete versus formal concepts was different between life and matter field. Thus, it is implied that science learning concepts are presented considering cognitive level of learner, and unit and content are constructed on the basis of properties of science fields in developing science curriculum and textbooks.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1170-1180
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• 2009

Recently this country has carried out the coast reclamation centering on the west and south coast for effective practical use of a country, considering purchase of materials and environmental problem, most reclaiming work is processing to spoil reclamation which is easy to secure the amount of materials. In case of weak ground that is formed by spoil reclamation like this, initial moisture content is high, as slurry state that is rarely revealed ground strength, compressibility and water permeability have been shown nonlinear change by compaction progress. Analysis of weak ground is unreasonable because the existing Terzaghi compaction theory analyzes compaction fixed number to regular invariable number for prediction of compaction state. This study computes the relation with void ratio-effective pressure and void ratio-finite transformation which is the most basic matter to predict finite strain compaction state of the south coast spoil, and analyze the basic feature to predict compaction feature of the south coast spoil reclaimed ground.

• International Journal of Oral Biology
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• v.39 no.4
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• pp.187-192
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• 2014

Nonthermal atmospheric pressure plasma has attracted great interest for biomedical applications. The plasma consists of charged particles, radicals, and a strong electric field as the fourth state of matter. This study evaluated the change in the surface roughness after tooth bleaching by plasma in combination with a low concentration (15%) of carbamide peroxide, specifically whether the application of plasma produced detriments, such as demineralization and structural change, with the goal of efficient and safe tooth bleaching. After being combined with plasma and 15% carbamide peroxide, the hydroxyapatite surface was significantly smoother with a low roughness average value. Tooth bleaching with 15% carbamide peroxide alone produced an irregular surface and increased the surface roughness with high roughness average value. Tooth bleaching with plasma resulted in no significant variations in hydroxyapatite in terms of change in surface roughness and surface topography. The application of tooth bleaching with plasma is not deleterious to dental hard tissue, implicating it as a safe tooth bleaching technique.

• Advances in environmental research
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• v.10 no.1
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• pp.17-41
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• 2021

Kazakhstan's cities experience high concentrations levels of atmospheric particulate matter (PM), which is well-known for its highly detrimental effect on the human health. A further increase in PM concentrations in the future could lead to a higher air pollution-caused morbidity and mortality, causing an increase in healthcare expenditures by the government. However, to prevent elevated PM concentrations in the future, more stringent standards could be implemented by lowering current maximum allowable PM concentration limit to Organization for Economic Co-operation and Development (OECD)'s limits. Therefore, this study aims to find out what impact this change in environmental policy towards PM has on state economy in the long run. Future PM10 and PM2.5 concentrations were estimated using multiple linear regression based on gross regional product (GRP) and population growth parameters. Dose-response model was based on World Health Organization's approach for the identification of mortality, morbidity and healthcare costs due to air pollution. Analysis of concentrations revealed that only 6 out of 21 cities of Kazakhstan did not exceed the EU limit on PM10 concentration. Changing environmental standards resulted in the 71.7% decrease in mortality and 77% decrease in morbidity cases in all cities compared to the case without changes in environmental policy. Moreover, the cost of morbidity and mortality associated with air pollution decreased by $669 million in 2030 and $2183 million in 2050 in case of implementation of OECD standards. Thus, changing environmental regulations will be beneficial in terms of both of mortality reduction and state budget saving.