• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.2
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• pp.25-36
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• 1995

It is important to separate the compostables from waste for successful operation of composting plant, since various compositions are mixed in it. For the separation of compostables, it is necessary to estimate total amounts of compostables from several sources. Based on it, required capacity and number of composting plant as well as proper waste collection and transportation system can be determined. So, amounts of garbage, major target material for composting. were estimated in this study. In survey of unit garbage generation(UGG). different estimation results would be obtained depending on the basis of its measurement. However, previous researches did not consider it. In this paper, the correlations between area and the number of user of garbage source were analyzed to find the related equations which were apllyed to estimation of total generation. Obtained results are as the following. Relative variations of measured UGG based on area and custumer are 62.5 and 52.8, respectively. In linear regression, related equation between area and custumer was Y=0.244X+59.0 (X=area, Y=custumer). The correlation factor r is 0.904. Equation Y=616.5X/(X+1215.4) was also obtained from linear regression using Monod equation (r=0.720). From the first order equation and measured data of UGG based on custumer, amounts of garbage generation from restaurant in Seoul and the whole country were calculated to 2043.9 ton/d and 9014.0 ton/d, respectively. But, the values calculated from measured data of UGG based on area were as low as 821.3 ton/d Cin Seoul) and 3821.0 ton/d(in the whole country). Consequently, the measurement of unit garbage generation based on the number of custumer was more favorable to lessen the points of survey and to guarantee the representative values. Especially, it would fit well on restaurant having statistics of area.

• Journal of the Mineralogical Society of Korea
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• v.22 no.1
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• pp.23-34
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• 2009

The adsorption of iodide on untreated bentonite and bentonites modified with organic cation (i.e., hexadecylpyridinium chloride monohydrate ($HDP^+$)) was investigated, and the organobentonites were characterized using uptake measurements, ${\mu}$-XRD, and electrophoretic mobilities measurement. Uptake measurements indicate that bentonite has a high affinity for $HDP^+$. Our ${\mu}$-XRD study indicates that organobentonites significantly expanded in basal spacing and organic cations were substantially intercalated into the interlayer spaces of bentonite. The electrophoretic mobility indicates that organobentonite tht is modified with organic cations in excess of the CEC of bentonite is completely different from untreated bentonite in the surface charge distribution. We found significant differences in adsorption capacities of iodide depending on the bentonite properties as follows: iodide adsorption capacities were 439 mmol/kg for the bentonite modified with $HDP^+$ at an equivalent amount corresponding to 200% of the CEC of bentonite whereas no adsorption of iodide was observed for the untreated bentonite. The molecular environments of iodine adsorbed on organobentonites were further studied using I K-edge and $L_{III}$-edge x-ray absorption spectroscopy (XAS). The X-ray absorption near-edge structure (XANES) of iodine spectra from organobentonites was similar to that of KI reference solution. Linear combination fitting of EXAFS data suggests the fraction of iodine reacted with the organic compound increased with increasing loading of the organic compound on organobentonites. In this study, we observed significant differences in the adsorption environments of iodide depending on the modified property of bentonite and suggest that an organobentonite has potential as reactive barrier material around a nuclear waste repository containing anionic radioactive iodide.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.235-242
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• 2017

In this study, we evaluated the polyphenol content, flavonoid content, antioxidant and biological of 70% EtOH extract and its fractions (dichloromethane, ethyl acetate and water) of the plant Chrysanthemum indicum L. (CI) belonging to family chrysanthemum. antioxidant activity was determined 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and superoxide scavenging activity. The biological activity tests included measurement of ${\alpha}$-glucosidase and PTP1B. The results show that content of polyphenol and flavonoid in 70% EtOH of CI 30.20 mg and 31.58 mg, respectively. Among the different samples, ethyl acetate (EA) fraction showed the highest level of polyphenol (87.87 mg) and flavonoid (65.12 mg). The DPPH, ABTS and superoxide dismutase(SOD) antioxidant assay of EA fraction showed 93.84%, 93.38% and 84.68% inhibition respectively. The EA fraction also showed the highest antioxidant activity compared to 70% EtOH extract and other fractions. EA fraction ($20{\mu}g/mL$) showed the highest 30.29% and 99.24%, respectively compared to other samples. The results of this study show that the EA fraction contained more antioxidant and antidiabetic components than 70% EtOH extract and other fractions. In conclusion, we believe that CI may be useful natural antioxidant and functional material.

• Journal of dental hygiene science
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• v.7 no.1
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• pp.37-47
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• 2007

Targeting dental hygienists who work in clinical division and public dental health division, this study was to investigate and analyze their working environment by work division, so that it could make basic material available in the interest of efficiently employing technical manpower specializing in public health and their better work environment in the future. 1. In terms of the sociodemographic characteristics of respondents, it was found that employees in public health were married in higher percentage and had higher age with longer career than those in clinical division, and it was noted that the former group had higher percentage in longer academic career than the latter group. 2. In terms of working days and hours, it was found that dental hygienists employed in public health worked 5 days a week(95.8%), while those in clinical division worked 6 days a week(70.3%). That is, the latter group worked longer days a week than the former group. 3. In terms of annual regular holidays, it was found that dental hygienists in public health division mostly took 11 to 20 days off a year, while those in clinical division mostly took 1 to 3 days off a year. That is, the former group is significant different in annual holidays from the latter group. 4. In terms of pay and allowances, it was found that most of public health group(89.4%) got monthly pay, while most of clinical group(65.4%) got the pay in annual salary. 5. In terms of reorientation experiences, it was found that 63.5% of total respondents didn't have any opportunity of domestic and overseas reorientation. And in terms of financial sponsorship for reorientation, it was noted that 54.0% of total respondents were financially supported for their reorientation by the institution they work for. 6. In terms of in-house welfare environment for married employees, it was found that 85.5% respondents ever faced no discrimination in job opportunities. In terms of the availability of maternity leave, it was noted that 69.2% respondents used the maternity leave, and 74.8% respondents used the maternity leave during 3 months. 7. In terms of quitting job, it was found that 46.8% respondents had ever left their job(public health group: 53.8%, clinical group: 45.8%), while the remaining 53.2% respondents(public health group: 46.2%, clinical group: 54.2%) had never left their job. Here, it is found that the employees in public health accounted for somewhat higher percentage in quitting job than those in clinical division. In terms of the number of leaving job, it was noted that most(50.8%) respondents left their job once, and there were similar distributions in quitting job between these both groups. In terms of the reason for quitting job, it was found that 29.2% respondents left their job due to desire for better pay(allowance) and working conditions.

• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.397-406
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• 2015

ZnO, II-VI group inorganic compound semi-conductor, has been receiving much attention due to its wide applications in various fields. Since the ZnO has 3.37 eV of a wide band gap and 60 meV of big excitation binding energy, it is well-known material for various uses such the optical property, a semi-conductor, magnetism, antibiosis, photocatalyst, etc. When applied in the field of photocatalyst, many research studies have been actively conducted regarding magnetic materials and the core-shell structure to take on the need of recycling used materials. In this paper, magnetic core-shell ZnFe₂O₄@SiO₂ nanoparticles (NPs) have been successfully synthesized through three steps. In order to analyze the structural characteristics of the synthesized substances, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR) were used. The spinel structure of ZnFe₂O₄ and the wurtzite structure of ZnO were confirmed by XRD, and ZnO production rate was confirmed through the analysis of different concentrations of the precursors. The surface change of the synthesized materials was confirmed by SEM. The formation of SiO₂ layer and the synthesis of ZnFe₂O₄@ZnO@SiO₂ NPs were finally verified through the bond of Fe-O, Zn-O and Si-O-Si by FT-IR. The magnetic property of the synthesized materials was analyzed through the vibrating sample magnetometer (VSM). The increase and decrease in the magnetism were respectively confirmed by the results of the formed ZnO and SiO₂ layer. The photocatalysis effect of the synthesized ZnFe₂O₄ @ZnO@SiO₂ NPs was experimented in a black box (dark room) using methylene blue (MB) under UV irradiation.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.3
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• pp.290-297
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• 2008

STATEMENT OF PROBLEM: Implant-supported fixed cantilever prostheses are influenced by various biomechanical factors. The information that shows the effect of implant number and position of cantilever on stress in the supporting bone is limited. PURPOSE: The purpose of this study was to investigate the effect of implant number variation and the effect of 2 different cantilever types on stress distribution in the supporting bone, using 3-dimensional finite element analysis. MATERIAL AND METHODS: A 3-D FE model of a mandibular section of bone with a missing second premolar, first molar, and second molar was developed. $4.1{\times}10$ mm screw-type dental implant was selected. 4.0 mm height solid abutments were fixed over all implant fixtures. Type III gold alloy was selected for implant-supported fixed prostheses. For mesial cantilever test, model 1-1 which has three $4.1{\times}10$ mm implants and fixed prosthesis with no pontic, model 1-2 which has two $4.1{\times}10$ mm implants and fixed prosthesis with a central pontic and model 1-3 which has two $4.1{\times}10$ mm implants and fixed prosthesis with mesial cantilever were simulated. And then, 155N oblique force was applied to the buccal cusp of second premolar. For distal cantilever test, model 2-1 which has three $4.1{\times}10$ mm implants and fixed prosthesis with no pontic, model 2-2 which has two $4.1{\times}10$ mm implants and fixed prosthesis with a central pontic and model 2-3 which has two $4.1{\times}10$ mm implants and fixed prosthesis with distal cantilever were simulated. And then, 206N oblique force was applied to the buccal cusp of second premolar. The implant and superstructure were simulated in finite element software(Pro/Engineer wildfire 2.0). The stress values were observed with the maximum von Mises stresses. RESULTS: Among the models without a cantilever, model 1-1 and 2-1 which had three implants, showed lower stress than model 1-2 and 2-2 which had two implants. Although model 2-1 was applied with 206N, it showed lower stress than model 1-2 which was applied with 155N. In models that implant positions of models were same, the amount of applied occlusal load largely influenced the maximum von Mises stress. Model 1-1, 1-2 and 1-3, which were loaded with 155N, showed less stress than corresponding model 2-1, 2-2 and 2- 3 which were loaded with 206N. For the same number of implants, the existence of a cantilever induced the obvious increase of maximum stress. Model 1-3 and 2-3 which had a cantilever, showed much higher stress than the others which had no cantilever. In all models, the von Mises stresses were concentrated at the cortical bone around the cervical region of the implants. Meanwhile, in model 1-1, 1-2 and 1-3, which were loaded on second premolar position, the first premolar participated in stress distribution. First premolars of model 2-1, 2-2 and 2-3 did not participate in stress distribution. CONCLUSION: 1. The more implants supported, the less stress was induced, regardless of applied occlusal loads. 2. The maximum von Mises stress in the bone of the implant-supported three unit fixed dental prosthesis with a mesial cantilever was 1.38 times that with a central pontic. The maximum von Mises stress in the bone of the implant-supported three-unit fixed dental prosthesis with a distal cantilever was 1.59 times that with a central pontic. 3. A distal cantilever induced larger stress in the bone than a mesial cantilever. 4. A adjacent tooth which contacts implant-supported fixed prosthesis participated in the stress distribution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.61-67
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• 2017

Chia seed (Salvia hispanica L.) originated from Central America is a highly nutritious food containing large amounts of linolenic acid, dietary fiber, and protein. This study investigated the quality properties and antioxidant activities of Sulgidduk prepared with chia seed powder as a functional material. Freeze-dried chia seed powder was replaced with 0, 1, 3, 5, and 7% of rice flour. The addition of chia seed powder did not affect water content, whereas the pH value of the chia seed group decreased as compared to the control. For color measurements, a and b values increased as the amount of chia seed powder increased, whereas L value decreased. Hardness and chewiness of Sulgidduk with chia seed powder were lower than those of the control, whereas springiness of the chia seed group was higher than that of the control. Cohesiveness was not significantly different in all samples. According to retrogradation analysis based on changes in hardness during storage, it was confirmed that addition of chia seed powder inhibited aging of Sulgidduk. Retrogradation of CSP5 was the slowest. Consumer acceptability analysis did not show significant differences in all samples. Total polyphenol and flavonoid contents tended to significantly increase as chia seed content increased. DPPH and ABTS radical scavenging activities of Sulgidduk were also elevated due to addition of chia seeds. From the results, addition of chia seed softened texture, inhibited aging, and enhanced antioxidant activities of Sulgidduk. It is concluded that addition of 5% chia seed powder, which showed high effectiveness for aging, is the most suitable for commercialization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.100-108
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• 2016

This study investigated the quality characteristics of factory-style ssamjang (FSS) and commercial handmade-style ssamjang (HSS) products. Moisture, crude protein, and crude fat contents were significantly higher in the HSS groups (49.37~62.12%, 9.39~13.46%, and 4.40~8.35%) than the FSS groups (41.94~45.83%, 7.50~9.09%, and 1.81~3.36%). Salt content was higher in the HSS groups (6.33~11.18%) than the FSS groups (6.10~7.57%). Moreover, the average salt content (7.51%) of the HSS groups and the FSS groups was lower than that of commercial ssamjang (8.73%). Hunter's color value was also significantly higher in the FSS groups. However, free sugar, organic acid, and free amino acids contents varied greatly between the FSS groups and the HSS groups, which was likely due to the different manufacturing method, ripening degree of doenjang and the main material used for ssamjang.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.27-39
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• 2009

Compulsive consumption is regarded as a global phenomenon that can adversely affect consumer well-being. Although the topic has been studied in different cultural settings, we have seen relatively little theory development and explanations of compulsive behavior Nearly all previous empirical studies attempt to explain this behavior by correlating measures of compulsive behavior with independent variables taken within the same time frame. However, recent developments in social sciences suggest that such a phenomenon may best understood in the context of the person's earlier-in-life experiences. Using the life course paradigm as an overarching framework, the present research extends previous work on this topic. Following hypotheses were drawn from literature review: H1: The earlier in childhood and adolescence a person experiences family dislocation, the greater his or her likelihood of exhibiting compulsive behaviors in adulthood. H2: The earlier in life the young person experienced family dislocation, the greater the number of family disruption events the young person experienced prior entering adulthood years. H3: Family dislocation leads to (a) increased frequency of socio.oriented family communications and (b) decreased frequency of concept-oriented family communication. H4: Young adults who were raised in families characterized by a strong socio-oriented communication structure are more likely to exhibit compulsive consumption tendencies than those who were raised in families characterized by a weak socio-oriented family communication structure. H5: Young adults who were raised in families characterized by a strong concept-oriented communication structure are less likely to exhibit compulsive consumption tendencies than those who were raised in families characterized by a week concept-oriented family communication structure. H6: The relationship between family disruption events experienced during adolescence and perceived stressfulness of these events is moderated by (a) global family support, (b) emotional family support, and (c) material family support. Those reporting higher levels of family support as teenagers are less likely to report experiencing stress due to family disruption events. H7: Perceived stressfulness of family disruption events experienced during adolescent years are associated with compulsive consumption tendencies in early adulthood. H8: The greater the number of family disruption events young adults experienced during their adolescent years the more frequent was their communication about consumption with their peers. H9: The more frequent was the young persons' communication with their peers about consumption during their adolescent years, the more likely they are to report compulsive buying tendencies as young adults. We use a sample of 120 Thai undergraduate students attending classes taught in English as part of a four-year international program. Product-moment correlations, hierarchical regression analysis and partial correlation were used to analyze data. Results of testing hypotheses showed that hypothesis 2, 4, 7 and 9 were supported and hypothesis 1, 3, 5, 6 and 8 were not supported. Our study did not find a significant relationship between the age when a person experienced family dislocation and their compulsive behavior tendencies expressed as young adults. We did not find a significant relationship between family dislocation and family communication structures. But we found a significant positive relationship between socio-oriented communication structure and compulsive buying and a significant relationship between our peer communication and compulsive buying measures. Also we found perceived stressfulness due to the disruptive events to have a significant positive relationship between the perceived stressfulness and compulsive buying. Implications from these findings, limitations of this research and future research suggestions were discussed.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.297-310
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• 1998

The purpose of this study was to investigate the initial tissue change, to repair on the teeth & surrounding tissue under the intrusive orthodontic forces by use of elastic chain, through the microscopic findings. For this study, three young adult mongrel dogs were used, and were divied into three group : the control group was deliveried only casting crown and the experimental group 1 was equipped with energy chain during 1 week and experimental 2 group was deliveried using energy chain during 1 week and 3 weeks observation. All experimental groups and control groups were sacrificed to make the samples for microscopic findings on premolar teeth. All samples were examed and compared the histologic changes through the microscopic with H-E stain. The obtained results were as follows. 1. In hematoxylin-eosin stain of the control group, the periodontal ligament was constant width from apical third to cervical third of the root, and the periodontal fiber arrangement was horizontal or oblique in cervical third, oblique in middle and apical third of the root. 2. In Masson Trichrome stain of the control group, osteoblast and osteoclast appeared in cervical third of root, and bone resorption and new bone formation was observed in middle and apical third of the root. 3. In experimental 1, osteoclasts were increased highly, and hyperemia of blood vessels and new bone formation and bone resorption by reversal line in apical third of the root were seen. PDL width was increased apprarently from crest to apex of the root and more in apical third. 4. In experimental 2, osteoclasts and hyperemia of blood vessels were more increased than control material in apical third of the root. PDL width was increased more than control group in root apex, and was seen less than experimental 1. PDL arrangement was similar to experimental 1 and was mixed only in root apex. Therefore, in premolar intrusion of the young adult dog, there were increased osteoclast, hyperemia and dilation of blood vessel, resorption of alveolar bone and cementum and different arrangement of PDL in initial tissue change. There was not observed complete repair after remove intrusive force.