• Journal of Radiation Protection and Research
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• v.25 no.4
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• pp.223-232
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• 2000

Comparative study was performed for the assessment of DNA damage and Chromosomal aberration in human lymphocyte exposed to low dose radiation using fluorescence in situ hybridization(FISH) and single cell gel electrophoresis(SCGE). Chromosomal aberrations in human lymphocytes exposed to radiation at doses of 5, 10, 30 and 50cGy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. FISH with chromosome-specific probe has been used to be a valid and rapid method fer detection of chromosome rearrangements induced by low dose radiation. The frequencies of stable translocation per cell equivalents were 0.0116, 0.0375, 0.040f, 0.0727 and 0.0814 for 0, 5, 10, 30 and 50cGy, respectively, and those of dicentric were 0.00, 0.0125, 0.174, 0.0291 and 0.0407 respectively. Radiation induced DNA damage in human lymphocyte in a dose-dependent manner at low doses from 5cGy to 50cGy, which were analysed by single tell gel electrophoresis(SCGE). From above results, FISH seemed to be useful for radiation biodosimetry by which the frequencies of stable aberrations in human lymphocyte can be observed more easily than by conventional method and SCGE also seemed to be sensitive method f9r detecting DNA damage by low dose radiation exposure, so that those methods will improve our technique to perform meaningful biodosimetry for radiation at low doses.

• Journal of Aquaculture
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• v.10 no.3
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• pp.261-271
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• 1997

Ammonia removal capacities of five submerged filter media, 2~3mm sand, 30~50mm gravel, 20~40mm coral sand, polythylene net, and corrugated plastic plate in a seawater recirculating system were tested. A rotating biological contactor (RBC) was also tested for comparison. Oxygen consumption rates were measured along with the ammonia removal efficiencies. The ammonia concentrations in the system were maintained from 0.052 to 0.904 mg/l (mean 0.338$\pm$0.219 mg/l) and the water temperature was ranged from 19.2 to $21.4^{\circ}C\;(mean 20.2^{\circ}C\pm0.58^{\circ}C$). The 1/2-order kinetic model (Y:g/$m^3$/day) and the mean ammonia removal rates (g/$m^3$/day) of the filter media were : Sand : Y=135.5X0.5-25.1(r2=0.8110), 45.1 Coral sand : Y=125.1X0.5-33.0 (r2=0.7307), 31.8 Polyethylene net : Y=87.4X0.5-20.1 (r2=0.6780), 25.2 Corrugated plastic plate : Y=87.4X0.5-20.1(r2=0.5206), 19.2 Gravel : Y=4307X0.5-5.5 (r2=0.2596), 17.1 RBC : Y=127.6X0.5-33.4 (r2=0.7146), 32.8 where X is the concentration of ammonia. Oxygen consumption rates well corresponded to the ammonia removal capacities of each filter medium, thus the sands showing the highest value (442g/$m^3$/day) followed by coral sands (291.1g/$m^3$/day), polyethylene nets (236.9g/$m^3$/day), gravels (135.6g/$m^3$/day) and corrugated plastic plates (134.2g/$m^3$/day). Oxygen consumption rate of the RBC was unable to measure because of the characteristics of the structure.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.231-242
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• 2008

Purpose: The purpose of this study was to investigate the bond strength of the core-veneer interface in all ceramic systems. Material and Methods: The all ceramic systems tested with their respective veneer were IPS Empress 2 with IPS Eris, IPS e.max Press with IPS e.max Ceram and IPS-e.max ZirCAD with IPS e.max Ceram. Cores (N=36, N=12/group, diameter: 10mm, thickness: 3mm) were fabricated according to the manufacturer's instruction and cleaned with ultrasonic cleaner. The veneer(diameter: 3mm, thickness: 2mm) were condensed in stainless steel mold and fired on to the core materials. After firing, they were again ultrasonically cleaned and embedded in acrylic resin. The specimens were stored in distilled water at $37^{\circ}C$ for 1 week. The specimens were placed in a mounting jig and subjected to shear force in a universal testing machine(Z020, Zwick, Germany). Load was applied at close to the core-veneer interface as possible with crosshead speed of 1.00mm/min until failure. Average shear bond strengths(MPa) were analyzed with a one-way analysis of variance and the Tukey test(${\alpha}=.05$). The failed specimens were examinated by scanning electron microscopy(JSM-6360, JEOL, Japan). The pattern of failure was classified as cohesive in core, cohesive in veneer, mixed or adhesive. Results: The mean shear bond strength($MPa{\pm}SD$) were IPS e.max Press $32.85{\pm}6.75MPa$, IPS Empress 2 $29.30{\pm}6.51MPa$, IPS e.max ZirCAD $28.10{\pm}4.28MPa$. IPS Empress 2, IPS e.max Press, IPS e.max ZirCAD were not significantly different from each others. Scanning electron microscopy examination revealed that adhesive failure did not occur in any all ceramic systems. IPS Empress 2 and IPS e.max Press exhibited cohesive failure in both the core and the veneer. IPS e.max ZirCAD exhibited cohesive failure in veneer and mixed failure.

• Journal of the Korean GEO-environmental Society
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• v.15 no.4
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• pp.5-11
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• 2014

Recently, there have been various lifeline installations constructed in the underground space of urban area due to the effective use of land. For newly installed lifelines or the management of the installed lifelines, many construction activities of excavation and backfilling are observed. Around these area, there are possibilities of collapse or excessive settlement due to the leaking of the pipe or unsatisfactory compaction of backfill material. Besides, construction costs can be saved since the on-site soils are used. The application of this liquidity filling material is not only to the lifeline installation but also to underpin the foundation under the vibrating machinery. On the evaluation of the applicability of this method to this circumstance, the strength should be investigated against the static load from the machine load as well as the vibration load from the activation of the machine. In this study, the applicability of the liquidity fill material on the foundation under the vibrating machinery is assessed via uniaxial compression and resonant column tests. The liquidity filling material consisting of the on-site soils with loess and kaolinite are tested to investigate the static and dynamic characteristics. Furthermore, the applicability of the reclaimed ash categorized as an industrial waste is evaluated for the recycle of the waste to the construction materials. The experimental results show that the shear modulus and 7 day uniaxial strength of the liquidity filling material mixed with reclaimed ash show higher than those with the on-site soils. However, the damping ratio does not show any tendency on the mixed materials.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1285-1297
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• 2020

In this study, we report the results of a study on the clinical evaluation of wrinkle improvement by developing a method for liposome of high-purity Centella asiatica extract used in pharmaceuticals and cosmetics, and a cream using the same. In order to make Centellasome-10EX stabilizing centella asiatica extract in liposome lamella vesicle, it could be completed using 5% hydrogenated lecithin and 2% sucrose distearate. The appearance of Centellasome-10EX was a creamy form of low viscosity, the color was pale yellow, and the odor had the inherent odor of the raw material. The pH was about 6.12, the specific gravity was 1.09, and the acid value was about 0.35. The content of the main constituents of centella asiatica extract contained in the liposome vesicle contains 10,800 ppm of asiatic acid, 10,900 ppm of asiaticoside, 6,000 ppm of madecasic acid, and 1,600 ppm of madecassoside, and long-term storage. There was no discoloration even at the time, and it was found that the main component remained stable thermodynamically. To mechanistically analyze the structure of the liposome vesicle of Centellasome-10EX, as a result of observation with a transmission electron microscope (Cryo-TEM), the multilayer vesicles are formed and filled with moisture, and there are 10 to 60 multilayers around it. It was confirmed that the liposome lamella vesicle was formed. As a clinical trial (in-vivo) test, the moisturizing effect of centellasome cream after application for 5 weeks was 28.3%, which was significantly increased compared to placebo. The skin elasticity effect was 13.6%, which significantly increased the moisturizing power than the placebo. The effect of improving fine wrinkles around the eyes was improved by 23.52% compared to placebo cream. Through the results of this study, it was possible to study the formulation and manufacturing method for encapsulation and stabilization of the developed Centellasome-10EX in the liposome vesicle. It is expected that the results obtained through clinical research on the wrinkle improvement effect of the cream using this can be widely used to study skin science in the cosmetic industry and to develop high-quality cosmetics with high efficacy.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.72-81
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• 2013

The objective of this study was to verify whether SCB(Slurry Composting & Bio-filtration) system can be applied for the treatment of anaerobic digestion(AD) wastewater and also, to identify the most effective set among three filtration compost beds tested. Results can be summarized as these; (a) When AD wastewater was sprayed on the top of beds which were mainly composed of sawdust and/or other media and, subsequently, filtrates collected and analyzed, there were large drop in the values of Electric Conductivity(EC), Total Suspended Solid(TSS), Biochemical Oxygen Demand(BOD), and Chemical Oxygen Demand(COD). In contrast, Total Nitrgen(T-N) and Total Phosphorus(T-P) were progressively elevated. We consider these changes as positive if the filtrate are to be utilized as liquid fertilizer. (b) When three sets of filtration beds (T1, T2, T3) were compared for their effectiveness, no significant difference was found among them. These indicate that expensive sawdust can be replaced in part with cheaper media such as woodchip, rice husks, or others. (c) At early stage of operation (within 20 days), BOD in filtrates were maintained at high level probably due to the lack of microbial activity. During the same stage, T-N, T-P was at low level but, were elevated to higher levels thereafter. These data, when combined, indicate that the filtration system needs at least a couple of weeks for the optimized microbial functioning. (d) The temperatures of the experimental beds were progressively dropped as the experiment continued through the fall season, although filtration effectiveness was not noticeably influenced.

• The korean journal of orthodontics
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• v.33 no.4 s.99
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• pp.293-305
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• 2003

The pharynx have significant locations and functions because it forms a part of the unit in which respiration and deglutition are carried out. Because of the closed relationship between the pharynx and the dentofacial and craniofacial structure, many studies are carried out on this subjects. The purpose of this study were to compare the airway size including pharynx, soft palate, tongue and hyoid bone between normal and hyperdivergent skeletal pattern and to evaluate the change of those size in different age. The sample of this study were consisted of 51 subjects in normal group, 52 subjects in hyperdivergent group. Each was divided into two subgroups by age , child group(9-l2yr old) and adult group(18yr old over). The lateral cephalometric radiographs were taken and the distance, angle and ratio of the facial skeleton, pharynx, soft palate, tongue and hyoid bone were measured and evaluated statistically. The result obtained were summarized as follows : 1 SN-Mn angle, FMA, and Pal-Mn angle were significantly larger in child group than adult group, but the lower anterior facial height(LAFH) and facial height ratio(FHR) were significantly smaller in child group than adult group. Occlu-Mn angle was significantly steep in hyperdivergent group than normal, but not significantly different between child group and adult group. 2. Hyperdivergent group and child group had the stronger correlation between SN-Mn angle, FMA, Pal-Mn angle, LAFH and FHR and airway size than normal group and adult group. Hyperdivevgent child group had significant negative correlation between SN-Mn angle, FMA, Pal-Mn angle and sagittal skeletal dimension of nasopharynx and sagittal depth of nasopharyngeal lumen. Significant positive correlation were seen between LAFH and vertical measurement of airway. 3. There was no difference of the linear measurement of airway size between hyperdivergent group and normal group. 4. Adult group had smaller posterior pharyngeal wall, target nasopharyngeal depth longer nasopharyngeal height and longer pharyngeal length than child group. 5. The sagittal measurement of hyoid bone had no difference between child group and adult group. But adult group had larger vertical measurement of hyoid bone than child group.

• The korean journal of orthodontics
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• v.33 no.4 s.99
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• pp.235-245
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• 2003

The goal of the present study was to evaluate the effects of PNAM appliance and cheiloplasty on alveolar molding. Samples consisted of 16 unilateral cleft lip and palate infants (10 males and 6 female, mean age=37.0 days after birth, average alveolar cleft gap=10.46m), who were treated with PNAM appliances by one orthodontist and rotation- advancement cheiloplasty by one surgeon in Seoul National University Hospital. Average duration of alveolar molding treatment was 13.10 weeks and these patients were recalled at average 8.31 weeks after cheiloplasty. These patients' models were obtained at initial visit (T0, mean age : $37.0\pm27.89$ days after birth), after successful alveolar molding (T1, mean age : $119.25\pm40.18$ days after birth), and after cheilopasty (T2, mean age : $190.81\pm42.78$ days after birth). Seven linear and five angular variables were measured using 1 : 1 photometry and soft ware program(V-ceph. Cybermed. Seoul, Korea). Paired t-test was performed to investigate statistical significance at p<0.05 level. 1 The posterior parts of alveolar segments were the stable structures during alveolar molding treatment period and after cheiloplasty in infants. 2. The closure of cleft gap during alveolar molding was usually due to backward bending of the whole part of the greater segment. 3. Although forward growth of the greater segment was hindered by alveolar molding, it resumed after cheiloplasty. 4. Increase of anterior inter-segment angle after cheiloplasty was due to the molding effect of the lip scar pressure.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.45-50
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• 2002

The 'hands-on' craftsmanship of the 20th century has came and gone. Today, we are dealing with whole new, 'cerebral approach,' to concept and design with this new approach, design and function are very much dependant upon planning, sales, promotion, and the formative technique of the design industry. The innovative process of design constantly change as it reflects the needs and wants of society. It is and industry that constantly change as it reflects the needs and wants of society. It is and industry that constantly remakes and reshapes itself to suit current trend and outlook. The current idea being that consumers are looking for quality over quantity. Due to the 20th centuries dominant philosophy of functionalism, production intended to standardize the individual's purchasing choice. Aesthetic, or philosophic qualities played a second fiddle to the functional bias of a product, With production, Marketing, and research and development are integrated into the management process. This translates as good which include efficiency, quality, durability, and credibility an trademark and style. There is a definite 'post-modernist' movement and style in 21st century. Every possibility is available as the old boundaries of the 20th century are laid aside. There is a new, transformative quality to the current paradigm of design. The old "should" and "should not" of design no longerapplies. The integrated rative of design solves the usual disparity between aesthetic qualities and production. Design and profirability need not be stranger to one another. It can differentiate the image perceived of both enterprises and consumers by making use of integrated goods services. With an integrated system. both producers and designers win. While design gets full access to design in turn. All consumers make decisions based upon the evaluation of quality, service, and image ; even though it may not be a conscious decision to do so. Consumers are fully integrated human beings ; therefore producers who apply the new, integrated paradigmatic approach to concept, design, and production will reap the harvest of making a true relationship with individual buyer.