• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.39-48
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• 1978

1) The decrease in strength of Raschel twines at Raschel joints is regarded to be due mainly to the frictional force between yarns and the unbalanced tensile distribution by the deformation of the joints. The rate of the decrease is about $13\%$ in lengthwise pull and 22 to $26\%$ in breadthwise pull. 2) The 3-course joint is less in deformation and stronger than the 2-course joint in all cases of pulls. 3) The variation of Raschel joint strength $T_R$ with the angle $\varphi$ between the adjacent bars is expressed as $T_R=T_{R0}-k\varphi$ where $T_{R0}$ is the strength at $\varphi=0^{\circ}$ and K is a constant. 4) The tensile strength ${\sigma}R$ and tile breaking energy $E_R$ of Raschel netting are given by $${\sigma}R=KN\;or\;${\sigma}R=T_RN$$ and $$E_R=AN$$ respectively, where N is the number of meshes at the pulling side, and K and A are constants. But the breaking energy of the netting is almost constant independent of tile variation of N. 5) The Raschel netting with some bars cut already breaks from tile joints of the bars next to the cut bars and its tensile strength, breaking energy, and breaking elongation decrease largily even if only one bar is in already cut state. 6) The tearing strength of Raschel netting is almost equal to the tensile strength of its single joint pulled by two bars. 7) The twisted joint is much more excellent in strength than the knot or the Raschel joint. The knot strength is 69 to $76\%$, and the Raschel joint strength is 71 to $74\%$ in lengthwise pull and 62 to $67\%$ in breadthwise pull, respectively, of the twisted joint strength.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.12 s.159
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• pp.1697-1707
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• 2006

Relentless advances in information technology are constantly transforming market dynamics of the retail industry. RFID is an emerging innovative technology that can reduce labor costs, improve inventory control and increase sales by effective business processes. Apparel retailers need to recognize the benefits of RFID and identify critical success factors. By focusing on apparel retailers, this study attempts (1) to identify the reality of RFID associated with benefits; and (2) to prospect the implementation of RFID in apparel retailing. We conducted a focus group interview with selected six panels who were experts of retail industry in the United States to obtain data regarding RFID attributes. Content analysis was used to generate related excerpts and classify 31 attributes of RFID benefits from the meaningful 173 responses. For experience of RFID, retailers were familiar with RFID technology and expressed the belief that RFID basically would support an existing retail system for speed to markets. However, retailers addressed the level of experience with RFID technology that they were still in the early adoption stage among few innovative companies. The content analysis identified five dimensions of RFID benefits for apparel retailing: Visibility and Velocity, Revenue Enhancement, Customer Service, Security, and Employee Productivity. This result lends support to the belief that RFID has a significant potential to streamline supply chain management, store operation and customer service for apparel retailing. This study provides intellectual and managerial implications far practitioners and researchers by postulating the effective use of RFID in the apparel retail industry.

• The korean journal of orthodontics
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• v.25 no.4
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• pp.403-414
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• 1995

The purpose of this study was to investigate the histologic changes in mandibular periodontium during overbite closure for openbite treatment by continuous arch wires and anterior vertical elastics. Two female monkey(Macaca nemestrina) with permanent dentition were used. Posterior bite block was fixed to each of their maxillae, which made the animal temporary anterior openbite as well as stabilized the whole maxillary anchorage. In each mandible, all the teeth except the second molars which had been extracted, were prepared for cast crowns. 018 inch Standard brackets were welded on these crowns. After cementation, two types of the $016{\times}022$ inch continuous arch wires, the plain ideal arch to the control animal and the MEAW(multiloop edgewise archwire) to the other experimental one were inserted. Then anterior vertical elastics were applied for two weeks. The overbite depth changes in the monkeys and histologic examinations of the mandibular periodontiums suggested the following conclusions. 1. During two weeks of the experimental period, the overbite increased + 0.3 mm in the control and + 1.3 mm in the experimental one. 2. In both the control and the experimental animal, histologic examinations showed that incisors, canines and first premolars were subject to extrusive force and the rest of posteriors were subject to intrusive one. 3. In periodontiums of the extruded incisors of the experimental one, reorientation of the periodontal fiber structures reflected the direction of force and the alveolar bone surfaces including apical and crestal areas which had been subject to tension, were the front of new bone formation. 4. In periodontiums of the extruded incisors of the experimental one, neither excessive hyalinization nor gross root resorption was observed. 5. Alveolar bone remodeling of anteriors and posteriors was more remarkable in the experimental one than the control.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.324-331
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• 2008

Introduction : Korean red ginseng has been shown to have an preventive effect on atheroma formation and enhancing effect on nitric oxide synthesis in endothelial cell inducing vasodilatation. However, there are few studies showing the effect of Korean red ginseng on blood pressure and vascular(endothelial) pathologic changes together. We designed this study to show changes of blood pressure and vascular pathologic findings with Korean red ginseng administration compared with Chinese red ginseng and control for 3 months in rats. Materials and methods : We studied the in vitro hypotensive effect and effect on vascular pathologic changes of Korean red ginseng compared with Chinese red ginseng and control. Rats were randomly assigned to three groups(Korean red ginseng, Chinese red ginseng and control) and evaluated by blood pressure and aortic vascular(endothelial) pathologic changes monthly during 3-month administration. All results were analyzed by paired T-test, ANOVA and post-hoc. Results : Blood pressure lowering effect was noted on Korean red ginseng and Chinese red ginseng compared to control. Especially, in Korean red ginseng group, hypotensive effect was showed in first and second month, but, in Chinese red ginseng group, it was just noted in first month. In case of vascular(aortic endothelial) pathologic finding, endothelial wall thickening and elastic fiber tearing were noted in Chinese red ginseng group compared with Korean red ginseng group and control with statistical significance.(p<0.05) Discussion : These results suggested Korean red ginseng could have more hypotensive effect and maintenance rather than Chinese red ginseng. And the difference of hypotensive effect between Korean red ginseng and Chinese red ginseng might has some association with difference of vascular pathologic findings in each group. However, further evaluation and research of other mechanism will be needed to convince this hypothesis.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.445-456
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• 2002

The purpose of this study were to determine that dexamethasone(Dex) induces differentiation of periodontal ligament(PDL) cells to osteoblastic cells and to investigate expression of matrix Gla protein(MGP), which is one of bone matrix protein. The isolated human PDL cells and gingival fibroblasts were prepared and cultured. The fourth or sixth sub-passage cells were used in this experiments. control group, ascorbic acid and ${\beta}$-glycerophosphate treated group, ascorbic acid, ${\beta}$-glycerophosphate and l00nM Dex treated group, ascorbic acid, ${\beta}$-glycerophosphate, and 5 ${\mu}M$ Dex treated group were made for study. The results were as follows: Cellular morphological change of PDL cells according to time was investigated. At first, the cells exhibited confluent monolayer of spindle or polygonal appearance. The multilayer of cells were seen after 7 days of treatment. After 14 days, the cells lost polarity and were densely packed. The mineralized nodule formation was seen at 21 days in the only Dex treated PDL cell groups. In the gingival fibroblast groups and no Dex treated PDL cell groups, the mineralized nodule was not seen. The mineralized nodule formation of 5 ${\mu}M$ Dex treated group was higher than 100 nM Dex treated group. Alkaline phosphatase(ALP) activity was higher in the Dex treated PDL cell groups of 14 and 21 days than 0 and 7 days. MGP was expressed in the control and all experimental groups and the expression was constant at 0,7,14,21 day. The above results confirm that Dex is affected to differentiation of the PDL cells to osteoblastic or cementoblastic cells and has dose-dependent effect for mineralization. And, MGP is expressed in the PDL cells and is not affected to mineralization of PDL cells.

• Journal of Animal Environmental Science
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• v.17 no.2
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• pp.71-80
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• 2011

Trickling filter has been extensively studied for the domestic wastewater treatment especially for the small scale plants in rural area. The purpose of this research is to survey the physical and microbial characteristics of wood chip media and the removal efficiency of animal wastewater using wood chip trickling filter system. The trickling filtration system comprises a filtration bed packed with wood chip media having a particle dia. of 5~7cm. The method comprises natural air from the bottom of the bed. The system also comprises a control mechanism including a time a constant discharge pump for controlling supply of the wastewater into the bed. The following conclusions were obtained from the results of this research. 1. The specific surface area of wood chip was 0.4123 $m^2$/g, pore volume was 0.0947 $cm^3$/g, density was 0.49 g/$cm^3$. It has forms of parallelogram and oblong which have numerous small pore space. This wood chip has been good condition for microorganism's habitat, having very larger specific surface area by complex the three dimension structure of cellulose at wood's major ingredients. 2. The total counts of in attached aerobic microbes were ranged from $10^6$ to $10^8$ CFU/g, and anaerobes microbial numbers were from $10^4$ to $10^7$. The aerobic microbial numbers appeared to be much more than those of anaerobic microbial numbers. 3. The average efficiency of $BOD_5$ and CODcr were 74.5% and 51.5%, respectively. The removal efficiency of T-N and T-P were 61.4%, 56.2%, respectively. But SS removal levels remain 19.3%.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.5
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• pp.345-350
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• 2012

To investigate the exposure and health risk assessment for the residents near the D-asbestos mine in Chungbuk, Korea. We analyzed asbestos in the 20 ambient air and 23 activity based samples near the mine. The airborne sample results are showed that 8 of 20 samples ranged between 0.0025 to 0.0029 f/cc (fiber per cubic centimeter) and the others were below the detection limit by phase contrast microscopy (PCM). In addition, asbestos fibers were under the detection limit or not being by transmission electron microscopy (TEM). Based on interview and survey targeting the local residents, we made the activity based sampling (ABS) scenarios fit to the conditions of field. At the same time, we calculated the excess lifetime cancer risk (ELCR) of these ABS scenarios according to the ELCR average value and 95% upper confidence limit (UCL). At the case of weed whacking, soil digging and sweeping yard scenario, 95% UCL of ELCR exceeded the $1{\times}10^{-4}$, acceptable risk range for exposure. Based on our study results, it is necessary safety measures such as risk communication, abatement or management of naturally occurring asbestos (NOA).

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.768-775
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• 2005

Lentinus edodes powder was added at 1-3%(w/w) to improve functional properties of jocheong. Content of crude protein, ash, crude lipids, total mineral, free sugar and reducing sugar increased with increasing amount of L. edodes powder, while viscosity and solid and carbohydrate contents decreased. Through amino acid analysis, 17 amino acids were identified and quantified, glutamic acid being the major amino acid. No significant differences were observed in fatty acid composition and pH between control and L. edodes powder-added jocheong. Addition of mushroom powder in jocheong decreased lightness, yellowness and redness in Hunter's color value. Sensor score of jucheong containing 1% of L. edodes powder was similar to that of control. Results showed jocheong containing less than 2% L. edodes powder gave highest scores in quality characteristics and sensory evaluation.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.57-65
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• 2000

Objective of research is obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(wood-based materials) were analyzed. Proximate analysis showed the wood-based materials contains 0.37~2.27% ash, 70~74% volatile matter, and 17~20% fixed carbon. As carbonization temperature was increased, the charcoal yield was decreased. However, no difference in charcoal yield was found due to time increase. The specific gravity after the carbonization decreased about 30~40% comparing to green wood. The charcoal had 1.08~4.18% ash, 5.88~13.79% volatile matter, and 80.15~90.94% fixed carbon. The pH of plywood and particleboard(pH 9 at $400^{\circ}C$, pH 10 at $600^{\circ}C$ and $800^{\circ}C$) made charcoals was higher than that of fiberboard. The water-retention capacity was not affected by the carbonization temperature and time. The water-retention capacity within 24h was about 2~2.5 times of sample weight, and the Equilibrium moisture content(EMC) became 2~10% after 24h. EMC of charcoal from the thinned trees were 9.40~11.82%($20^{\circ}C$, RH 90%), 6.87~7.61%($20^{\circ}C$, RH 65%), and 1.69~2.81%($20^{\circ}C$, RH 25%). EMC of charcoal from the wood-based materials under $20^{\circ}C$, relative humidity(RH) 90% was similar to EMC of charcoal from the thinned trees(9~11 %). However, under $20^{\circ}C$, RH 25.65%, EMC of charcoal from the wood-based materials were higher(2~3%) than EMC of charcoal from the thinned trees. Every charcoal from the wood-based materials fulfilled the criteria in JWWA K 113-1947.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.3
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• pp.13-22
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• 2022

In order to improve water quality of the water system contaminated with dyes, biochars prepared using discarded waste resources were applied in this study. Biochars with a large specific surface area were manufactured using street tree pruning products or waste wood, and were applied to remove an organic dye in synthetic water. Biochars were made by pyrolysis of typical street tree porch products (Platanas, Ginkgo, Aak) and waste wood under air-controlled conditions. Methylene blue (MB), which is widely used in phosphofibers, paper, leather, and cotton media, was selected in this study. The adsorption capacity of Platanas for MB was the highest and the q_max value obtained using the Langmuir model equation was 78.47 mg/g. In addition, the adsorption energy (E) (kJ/mol) of MB using the Dubinin-Radushkevich (D-R) model equation was 4.891 kJ/mol which was less than 8 kJ/mol (a criteria distinguishing physical adsorption from chemical adsorption). This result suggests a physical adsorption with weak interactions such as van der Waals force between the biochar and MB. In addition, the physical adsorption may resulted from that Platanas-based biohar has the largest specific surface area and pore volume. The ∆G value obtained through the adsorption experiment according to temperature variation was -3.67 to -7.68, which also suggests a physical adsorption. Considering these adsorption results, the adsorption of MB onto Platanas-based biochar seems to occur through physical adsorption. Overall, it was possible to suggest that adsorption capacity of the biochr prepared from this study was equal to or greater than that of commercial activated carbon reported in other studies.