• The korean journal of orthodontics
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• v.40 no.5
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• pp.304-313
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• 2010

Objective: The aim of this study was to evaluate the occlusal force and contact area and to find its associating factors in Koreans. Methods: Occlusal force and contact area in maximum intercuspation were measured using the Dental $Prescale^{(R)}$ system in 651 subjects (15 with normal occlusion, 636 with various malocclusions divided into subgroups according to the skeletal pattern, Angle's molar relationship, age and gender). Results: Occlusal force of the normal occlusion group ($744.5{\pm}262.6N$) was significantly higher than those of the malocclusion group ($439.0{\pm}229.9N$, $p$ < 0.05). Occlusal force was similar regardless of differences in ANB angle or Angle's molar classification, however the increase in vertical dimension significantly reduced occlusal force ($p$ < 0.05). Conclusions: Occlusal force was significantly lower in the malocclusion group compared to the normal occlusion group, and in females compared to males, but it was not affected by age, antero-posterior skeletal pattern or molar classification. Although a hyperdivergent facial pattern indicated lower occlusal force compared to a hypodivergent facial pattern, the differences in skeletal pattern were not the primary cause of its decrease, but a secondary result induced by the differences in occlusal contact area according to the facial pattern.

• Journal of Plant Biology
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• v.37 no.3
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• pp.387-394
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• 1994

Effects of environmental factors of light, temperature, nitrogen sources and water stress were analyzed quantitatively on the nodule formation and nitrogen fixation activity of autumn olive plant (Elaeagnu$ umbellala Thunb.) during the seedling growth. Seedlings showed the maximum nitrogenase activity of $72.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ in the early nodulation stage. The relative growth rate and T/R ratio changed from $1.60%{\cdot}d^{-1}$ and 1.12 in the earlier stage to $3.75%{\cdot}d^{-1}$ and 2.31 in the later stage, respectively. light conditions of 20-25, 1015 and 4-6% resulted in decreases of 41, 54 and 71% of the nitrogenase activity, respectively. Nodules incubated in 15, 20, 25 and $30^{\circ}C$ showed the activities of 5.4, 24.7, 51.6 and $58.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ respectively. Pretreatment with low temperature ($15^{\circ}C$) followed incubation at $30^{\circ}C$ attained higher nitrogenase activity ($66.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$) than that with higher temperature ($35^{\circ}C$). The oxygen pressure above 16 kPa is necessary for saturation of the nodule activity, but the activity was inhibited severely by physical impact such as the exision or isolation of nodules from the root. The relative activities of early nodules grown in pH 5.5, 6.5 and 8.0 were 89, 100 and 40% and those grown in 1 and 3 mM of $NO_3\;and\;NH_4$ were 6, 1 and 68, 50%, respectively. Watering levels of 20, 50 and 100 mL during the seedling growth resulted in 35, 120 and 8 mg of nodule formation and 33.6, 58.4 and $8.4\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ of the nitrogenase activity, respectively. Water stress with 86% decrease of soil water content caused temporary wilting point of leaf and a complete disappearance of nitrogenase activity of nodules, though the water content and transpiration rate in plant were reduced to 90 and 53%, respectively.tively.

• Management & Information Systems Review
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• v.38 no.4
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• pp.137-157
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• 2019

Companies are trying to use enterprise SNS for collaboration and speedy decision-making. This study verified the mediating effect of communication between enterprise SNS and job performance, and proved the moderating effect of nationality between enterprise SNS and communication. This study collected survey data of 81 Korean and 81 Chinese from employees who have used enterprise SNS in Korea and China. As results of data analysis, first, enterprise SNS improved job performance through speedy information sharing and error reduction. Second, communication mediated the effect of enterprise SNS on job performance. Third, enterprise SNS increased the level of organizational communication through decreasing the burden of offline face-to-face communication. Compared with Chinese corporate organizations, Korean corporate organizations have high power distances, centralized control, and high superior authority. Therefore, in the off-line communication situation, the subordinate feels the social pressure to follow the command of the superior. Thus communication is one-way and closed. In this Korean organizational situation, corporate SNS can be used as a means to bypass rigid offline communication. In the online communication environment of non face-to-face corporate SNS, anxiety and stress of face-to-face communication can be reduced, so communication between the upper and lower sides can flow more smoothly. The contribution of this paper is that it proved that enterprise SNS promotes communication and improve job performance by reducing the anxiety or stress of offline communication, while according to prior research successful adoption of many types of information systems requires the fit between an organization and its organizational culture.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.372-380
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• 2009

After supercritical water treatment of poplar wood meals (passed through 60 mesh) for 60s between 325 and $425^{\circ}C$ at the fixed pressure at $220{\pm}10atm$, some solid residues were present in the degradation products. They mainly consisted of chemically modified lignin and fibrous materials. Glucose and xylose were identified as main sugar components of fibrous materials, and the highest ratio of glucose/xylose was achieved at the highest reaction temperature. As reaction temperature was elevated, the portion of fibrous materials decreased in the solid residues, while lignin was further accumulated. The H : G : S ratio of lignin in solid residues was estimated by analytical pyrolysis. Irrespective of reaction temperatures, the H:G:S ratios were not significantly changed in the lignin in solid residues. Compared to poplar milled wood lignin (MWL), it was remarkable that H type monomers were further lowered, while portion of S type monomers increased. The amount of G type monomers were relative stable. In presence of HCl catalyst, lowering H type as well as enhancing S type was further distinguishable. According to the result of nitrobenzene oxidation (NBO), ca. 265 mg of vanillin and syringaldehyde was yielded from poplar MWL as main products. However, remarkably reduced amount of NBO products were determined from solid residues by raising operating temperature as well as by the addition of HCl catalyst. These results strongly indicate that $\beta$-O-4 linkage could be easily cleaved during supercritical water treatment, so that the lignins in the solid residues seem to be condensed phenol polymers, which are mainly formed by carbon-carbon linkages rather than $\beta$-O-4 linkage.

• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.293-303
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• 2012

Recently, as construction technology improved, concrete structures not only became larger, taller and longer but were able to perform various functions. However, if extreme loads such as impact, blast, and fire are applied to those structures, it would cause severe property damages and human casualties. Especially, the structural responses from extreme loading are totally different than that from quasi-static loading, because large pressure is applied to structures from mass acceleration effect of impact and blast loads. Therefore, the strain rate effect and damage levels should be considered when concrete structure is designed. In this study, the low velocity impact loading test of steel fiber reinforced concrete (SFRC) slabs including 0%~1.5% (by volume) of steel fibers, and strengthened with two types of FRP sheets was performed to develop an impact resistant structural member. From the test results, the maximum impact load, dissipated energy and the number of drop to failure increased, whereas the maximum displacement and support rotation were reduced by strengthening SFRC slab with FRP sheets in tensile zone. The test results showed that the impact resistance of concrete slab can be substantially improved by externally strengthening using FRP sheets. This result can be used in designing of primary facilities exposed to such extreme loads. The dynamic responses of SFRC slab strengthened with FRP sheets under low velocity impact load were also analyzed using LS-DYNA, a finite element analysis program with an explicit time integration scheme. The comparison of test and analytical results showed that they were within 5% of error with respect to maximum displacements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.442-449
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• 2017

This study was carried out to analyze the antioxidant components and activities of cooked mixed grain rice-added foxtail millet with different addition rates (5, 10, 15, and 20%) and cooking methods. The two foxtail millet varieties used in this study were non-waxy foxtail millet, 'Samdame', and waxy foxtail millet, 'Samdachal'. Cooked mixed grain rice-added foxtail millet was cooked by general and high pressure cooking methods with and without fermented alcohol. Except for breakdown viscosity, pasting characteristics of foxtail millet were reduced with increasing amounts of foxtail millet. Water-binding capacity and swelling power significantly decreased with increasing amounts of foxtail millet, whereas water solubility index significantly increased. Total polyphenol and flavonoid contents increased with increasing amounts of foxtail millet. DPPH and ABTS radical scavenging activities also increased with increasing amounts of foxtail millet. Moreover, foxtail millet cooked by general cooking method with fermented alcohol showed higher antioxidant effect compared to other cooking methods. In this study, antioxidant components and activities of cooked mixed grain rice-added foxtail millet with different addition rates and cooking methods can be used as basic data for manufacturing processed products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.232-237
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• 1994

Changes of volatile components in modified oleoresin red pepper during cooking at high temperature were investigated. Dried red pepper was milled to 100mesh of size particle and oily compounds were extracted by reduced pressure steam distrillation. The rest part was reextracted and concentrated. The extracts were combined. The same volume of water and 4% of polyglycerol condensed ricinoleate (PGDR) were added to the combined extract, and emulsified to make oleoresin red pepper 119 volatile compounds were separated from the dried red pepper and oleoresin and 35 components were identified in both samples. The major flavor compounds were identified to be 2-methoxy-phenol, 2, 6-bis(1, 1-dimethylethyl)-4-methyl-phenol, 1, 4-dimethylbenzene, thylbenzene, 1, 2-benzenedicarboxylic acid, 2-methoxyl-4-methylphenol, 4-ethyl-2-methoxy-phenol, and 5- methyl-2-furancarboxyaldehyde, and their transferal from raw red pepper to oleresin was low. 93 voltilie compounds were isolated after 3 hours cooking at 100 and 82 volitile compounds were separated after that at $150^{\circ}C$. Degeneration of volatile compounds was peculiarly proportional to the temperature of cooling. Capsaicin was relatively stable during cooking and remaining ratio after cooking at 100 and $150^{\circ}C$ was 84.7% and 73.3%. respectively. Oleoresin from red pepper had a little antioxidation effect at $100^{\circ}C$ cooking, but, antioxidation effect at $150^{\circ}C$ cooking was not shown due to degradation of capsaicin.

• Sleep Medicine and Psychophysiology
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• v.6 no.2
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• pp.126-132
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• 1999

Objectives: The purposes of this study were to investigate 1) the incidence of insomnia, 2) the clinical characteristics of the insomniacs, 3) the correlation of severity of insomnia with somatic complaints and psychological distresses, and 4) the beliefs and attitudes about sleep in patients with chronic renal failure on hemodialysis. Methods: The author evaluated 153 patients, receiving hemodialysis therapy at the four outpatients hemodialysis units in Pusan, Korea. The patients had completed a self-administered questionnaire package, which consisted of basic demographic findings, questions characterizing insomnia, Beck Depression Inventory(BDI), Spielburger's State-Trait Anxiety Inventory(STAI), and visual analogue scales measuring quantitatively the severity of the self-perceived psychological and somatic symptoms. And several laboratory data were collected. Diagnosis of insomnia was made in the base of insomnia criteria of DSM-IV and international classification of sleep disorders. Subjects were dichotomized into those who reported any characteristics of insomnia or those who had no insomnia during the preceding two weeks. Results: Insomnia was found in 100(65.4%) of 153 patients. No statistical differences were found between the patients with and without insomnia in terms of age, gender, education, marital status, mean duration of hemodialysis and all considered laboratory findings except serum albumin. The patients with insomnia had significantly higher BDI score and predialysis systolic blood pressure, and lower serum albumin as compared to non-insomnia group. Significant differences were found between two groups in terms of self-perceived distress such as sadness, anxiety, worry, pruritus, and dysfunction of daily life. The data showed statistically significant correlation between insomnia severity and some variables such as physical dysfunction, pruritus, bone pain, sadness, anxiety, worry, dysfunction of daily life and excessive daytime sleepiness. The patients with insomnia had significantly several dysfunctional beliefs and attitudes about sleep than those without insomnia. Conclusion: These results indicate that insomnia is very common in hemodialysis patients and likely contribute to the impaired quality of life experienced by many these patients. The author suggests that physical and psychological distresses would be reduced and the quality of life could be improved if their sleep disturbances are properly ameliorated in patients on hemodialysis.

• Journal of the Korean Geographical Society
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• v.29 no.2
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• pp.137-165
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• 1994

Structural adjustment of industry (or industrial restructuring) seems to be inherent in the process of capitalist economic development, which tends to be proceeded with shifts from one stage to another in order to overcome structural crises generated in each stage. The structural adjustment of industry is necessarily accompanied with regional restructuring, since it is not only projected on spece, but also mediated by space. Such a restructuring necessitates industrial and uneven regional devlopment through which capital can seek excessive profits over the rate of socio-spatial average. The industrial restructuring and uneven regional development in the 1980s in Korea can be seen as a process in which capital attempted with a strong support of the govenment to overcome the crises in the end of 1970s and hence to go on rapid economic growth. In this process, capital, especially monopoly capital concentrated into few conglomerates, pursued both extensive expansion and intensive development of industry simultaneously. In results, the Korean economy could eliminate some of peripheral characters and maturate the Fordist accumulation system. The extensive expansion of the Korean industry in the 1980s was stimulated mainly through the enlargement and adjustment of investment for equipment facilities which was planned to exclude or rationalize traditional light industries on some places, and to continue rapid growth of key heavy-chemical industries, especially of fabricated metal industry, on other places. In this process, keeping mainly the existing developmental axis which polarized the Seoul Metroplitan region and the Southeast region in Korea, the enhancing spatial mobiiity of capital and the further differentiating division of labour enforced a tendency of concentration of all types of industry in the Seoul Metropolitan region, and at the same time provoked the diffusion of some industries over Jeolla and Chungchong regions in a considerable extent. The intensive development of industriai structure in the 1980s was pursued through the strategic encouragement of subcontracting small firms mainly which produced assembling components, the technical enhancement and factory (semi-) automation, and the enrichment of service industries for estate management, finance, distribution and retailing which supported and complemented the production of goods. In this process, enabling capital to extend and elaborate its domination over space through the reorganization of regulating systems, the Fordist division of labour generated a socio-spatial hierarchy in the nation-wide scale that characterized: the Seoul Metropolitan region as an overmaturated (or overarching) Fordist region performing the conceptive functions of management, research and development, in which all types of industry (including service industries) tended to be reconcentrated; Kyungsang region as a maturated Fordist region with excutive branches of large conglomerates and with subcontracting firms around them which produced standardized products through the automized production processes in secialized Fordist industries or rationalized traditional industries; and Jeolla and Chungchong regions as newly devloping Fordist regions with newly migrated branches and some subcontracting small firms-in relatively older Fordist industries or partly rationalized traditional industries. From these analyses, it can be argued that the structural adjustment of the Korean industry in the 1980s, which had carried out both through the extensive expansion and the intensive deveiopment, strengthened further uneven regional development process, even though it appears to have reduced apparently the economic and regional disparity by balancing numerically large and small firms and by extending the Fordist industrial space nation-wideiy. And it seems more persuasive to see that the Korean industrial structure in the 1980s maturated the Fordist system of accumulation, but not yet transformed towards the post-Fordist (or the so-called flexible) accumulation system, even though the Korean economy in the 1990s seems to be under a pressure of restructuring towards the latter system.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.32-40
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• 2017

Purpose: Obesogenic environments in children, in particular excessive intake of sodium, generate hypertension, which is a major risk factor for chronic diseases. Methods: In all, 725 children, 379 boys and 373 girls, aged 8~9 years were recruited from seven elementary schools in Kuro-ku, Seoul. To evaluate whether or not obesity risk was modulated by salt-sensitive genes, Solute Carrier Familiy 12 member 3 (SLC12A3) was used as the target. After children were assigned into obese (BMI > 85 percentile) or non-obese groups, anthropometry, blood biochemistry, and dietary intakes were measured according to the genotypes GG (wild) or GA+AA (hetero+mutant). Results: Without gender differences, high TG and low HDLc were detected in the obese group compared to the non-obese group. Regardless of obesity, weight gain and blood pressure (BP) increased in the SLC12A3 GA+AA genotype rather than in the GG type. HDLc was associated with obesity risk without genotype difference. Odd ratios for risk of obesity were 15.57 (95% CI 2.192~110.654), 22.84 (95% CI 1.565~333.469), and 9.32 (95%CI 1.262~68.817) in boys and girls with GA+AA genotypes as sodium intake increased above 4,000 mg/day. Dietary calcium, sodium, folate, and vit C were associated with obesity risk according to gender or genotype differences. Since high folate intake reduced obesity risk in only boys with GG type. Risk for overweight and obesity increased in boys with GA+AA genotypes and dietary habits with high sodium and cholesterol and low folate. Conclusion: The A allele of SLC12A3 rs11643718 was sensitive to development of obesity in children as sodium intake increased.