• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.655-663
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• 2016

Increasing green house gas and it consequent climate change problems are discussed as a global issue. Accordingly, future local green house gas emission will increase up to 40% of the entire local green house gas emission and therefore, efforts to reduce the emission in construction industry is urgently required. Therefore, in this study, heating energy demand was analyzed by using the EnergyPlus simulation according to wood material finishes configuration. EnergyPlus has the entry for a variety of buildings and heating, ventilation, air conditioning (HAVC) system components, in particular buildings, air conditioning systems, and performs simultaneous integrated calculated through the feedback between the heat source unit, a verification program according to the ASHRAE Standard 140-2007 to be. The climate data for the simulation we used the data IWEC in Incheon and Gwangju provided by EnergyPlus. The analysis of simulation model was farm and fishing house standard design drawings: 2012, presented at the Korea Rural Community Corporation. The results of simulation of central region and southern region were effected by wood products of simulation model into the interior finish, exterior finish, windows, wooden structure. Also, it was confirmed that the reduced heating energy demand.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.307-315
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• 2016

The aim of this research is analyzing the fundamental properties and autogenous shrinkage reducing performance of 70 and 100MPa grade high performance concrete including emusified refined cooking oil(ERCO) under the mock-up conditions. As a results of experiment, the mixture contained 0.5% of ERCO showed slightly decreased slump flow while the slump was increased and segregation resistance performance was improved as 2.5 of EIS. For air content, all mixtures satisfied target air content with increased unit weight and delayed setting time with ERCO addition. In the case of compressive strength, when ERCO was added 0.5%, the result of approximately 5 to 10% of increased compressive strength was observed. For the autogenous shrinkage, ERCO contributed on 20-30% of shrinkage reducing performance comparing to Plain mixture without ERCO. It is considered that capillary pore filling action of soap particles occurred by the reaction of ERCO in cement paste between fatty aicd and calcium hydroxide contributed the shrinkage reducing performance. Based on these mock-up test results, application of the high performance concrete mixture with ERCO on CFT actual structure was decided.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.156-161
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• 1982

Three plastic film solar dryers covered with different film layer were constructed by modifying farm vinyl house and studied their performance. The collection efficiency and temperature raising of type C which was covered with double layers of transparent PE and black PVC film was most efficient, followed after B covered with double layer of transparent PE film and type A covered with single layer transparent PE film. The inside temperature of type C was average $18^{\circ}C$ higher than ambient temperature and its collection efficiency showed 31.5% with air flow rate of $3.8m^3/min$. The solar energy collection efficiency of type C was increased in proportion to air flow rate up to 60.2% at $11.3m^3/min$. In demonstration drying test of red pepper in type C, drying capacity per unit area was 2.5 times higher than that of conventional solar drying on straw mat and drying time shortened to about half.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.123-138
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• 2018

To sustainably monitor air pollution in Seoul, the number of Air Pollution Monitoring Station has been gradually increased by Korea's Ministry of Environment. Although particulate matters(PM), one of the pollutants measured at the stations, have an significant influence on human body, the concentration of PM in Korea came in second among 35 OECD member countries. In this study, using the data of PM concentration from the stations, distribution maps of PM10 and PM2.5 concentrations over Seoul were generated, and spatial factors potentially related to PM distribution were investigated. Based on a circumscribed hexagon about a circle in radius of 500 meters created as a basic unit, Seoul was sectionalized and PM concentration map was generated using the interpolation technique of 'inverse distance weighting'. The distributions of PM concentrations were investigated with commuting time by administrative district and the outcome was related with land-use type and volume of traffic. Results from this analysis indicated distribution pattern of PM10 concentration was different from that of PM2.5 by administrative district and time. The distribution of PM concentration was strongly related to not only the size of business and trafficked areas among the land-use type, but also the existence of urban green. Further analysis of the relationship between the PM concentration and detailed land-use and urban green maps can be helpful to identify spatial factors which have an impact on the PM concentration on the regional scale.

• Journal of Environmental Science International
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• v.21 no.5
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• pp.633-640
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• 2012

White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth. On the other hand, in the results of examining physiological changes before and after treatment on fine dust PM10 and carbon dioxide removal capacity in a closed chamber under an artificial light source, the patterns of carbon dioxide and fine dust removal were similar among the treatment groups according to light condition, but according to plant type, the removal rate per unit leaf area was highest in $Spathiphyllum$ and lowest in $Dieffenbachia$. In the experiment on dust and carbon dioxide removal, the photosynthetic rate was over 2 times higher after the treatment, and the rate increased particularly markedly under compound light and white light, suggesting that the photosynthetic rate of plants increases differently according to light quality. These results show that light quality has a significant effect on the photosynthetic rate of plants, and suggests that plants with a high photosynthetic rate also have a high carbon dioxide and dust removal capacity. In conclusion, the photosynthetic rate of foliage plants increased under white and blue light that affect photosynthesis and the increased photosynthetic rate reduced carbon dioxide and fine dust, and therefore white and compound light were found to be the optimal light sources most functional and economically efficient in improving ornamental value and indoor air quality.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.225-236
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• 2016

Objectives: Nanomaterials have been used in various fields. As use of nanoproducts is increasing, workers dealing with nanomaterials are also gradually increasing. Exposure assessments for nanomaterials have been carried out for protection of worker's health in workplace. Exposure studies were mainly focused on manufacturing processes, but these studies on after-treatment processes such as refinement, weighing, and packing were insufficient. So, we investigated exposure characteristics of particles during after-treatment processes of $Al_2O_3$ fibers and Ni powders. Methods: Mass-production of Ni powder process was carried out in enclosed capture-type canopy hood. In a developing stage, $Al_2O_3$ was handled with a local ventilation unit. Exposure characteristics of particles were investigated for $Al_2O_3$ fiber and Ni powder processes during the periods of 10:00 to 16:00, 20 May 2014 and 13:00 to 16:00, 21 May 2014, respectively. Three real-time aerosol instruments were utilized in exposure assessment. A scanning mobility particle sizer(SMPS, nanoscan, model 3910, TSI) and an optical particle counter(OPC, portable aerosol spectrometer, model 1.109, Grimm) were used to determine the particle size distribution in the size range of 10-420 nm and $0.25-32{\mu}m$, respectively. In addition, a nanoparticle aerosol monitor(NAM, model 9000, TSI) was used to measure lung-deposited nanoparticle surface area. Membrane filters(isopore membrane filter, pore size of 100 nm) were also used for air sampling for the FE-SEM(model S-5000H, Hitachi) analysis using a personal sampling pump(model GilAir Plus by 2.5 L/min, Gilian). Conclusions: For Ni powder after-treatment process, only 27% increase in particle concentration was found during the process. However, for $Al_2O_3$ fiber after-treatment process, significant exposure(1.56-3.34 times) was observed during the process.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.160-163
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• 1998

In this study, the compostable household wastes from a house were composted in a home composter without adding any bulking agent and microorganisms. Every day wastes of 1kg were added to the composter during the experimental period. The following results were obtained : 1. Each component of the compostable household wastes generated every day showed very difference. 2. While composting proceeded at room temperature by suppling 1,1322 l air per hour, the composting material maintained the water content of 74.36 ${\sim}$ 85.14%, whereas while composting proceeded at $45^{\circ}C$ by suppling 427 l air per hour, the compost had optimal water content. The electric power of 132kwh a month was required by operating the composting unit at $45^{\circ}C$. 3. During 20 day, decomposition of 28% at room temperature and 44% at $45^{\circ}C$ were obtained respectively. 4. The accumulation of inorganic compound contents were not shown during the composting period, However, the content of salt and Cd was very high. Therefore, using the compost for agriculture has to be careful. 5. The biofilter removed the odorous substants efficiently at the room temperature due to increasing surface loading.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.414-422
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• 1992

To keep up with urgent need of continuous, effective and rapid drying unit, a fluidized bed drying system with computer controlling air temperature, velocity and relative humidity was designed. This study was attempted to determine physical properties and some basic experiments of fluidized bed d교ing of barley. Also experimental data of the designed fluidized bed drying system using the barely were compared with those of published equations to confirm the reliability of the system and the following results were obtained. The physical dimension husked barley were shown larger than that of naked barley from the experiment. When air temperature. relative humidity and charged amount were $35^{\circ}C$, 30% and 300g respectively, the minimum fluidization velocity of naked and husked barley were found 1.5 m/s and 1.7 m/s. And the optimum fluidization velocity was shown as 3.0 m/s from the experiment. The empirical equation of $U_{mf}$ in this fluidized system was obtained as follow; $U_{mf}^2= \frac{{\phi_s}\;d_p}{Hk}\;{\cdot}\;\frac{(\rho_s-\rho_g)g\;{{\varepsilon}_{mf}^3}} {\rho_g}(Re_p>1,000)$ Where HK=0.4881 for naked barley, 0.6649 for husked barley.

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.107-119
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• 1990

The purpose of this study was to evaluate the marginal adaptability of the amalgam restorations in applying the cavity varnish (Copalite$^{(R)}$) and dentin bonding agent (Scotchbond 2$^{(R)}$) under the scanning electron microscope. For this study, eighteen sound extracted human molars were selected. Class I cavities in 12 teeth and class V cavities in 6 teeth were prepared using an air turbine with No. 701 tungsten carbide bur and finished using a low speed handpiece with No. 557 fissure bur. The prepared specimens were then divided into three groups including 4 class I cavities and 2 class V cavities in each group and restored as follows ; Group I. All the prepared cavities were restored with amalgam only (Control). Group II. Two layers of Copalite$^{(R)}$ cavity varnish were applied to the cavities with a gentle stream of air after each application and cavities were restored with amalgam. Group III. The enamel cavity margins were etched with 37% phosphoric acid gel for 60 sec., rinsed for 30 sec. and dried. One layer of visible lightcured Scotchbond Dental Adhesive$^{(R)}$ was applied and immediately cured for 20 seconds with visible light-cure unit and cavities were restored with amalgam. All the specimens were cut at the neck of the teeth and the occlusal halves of specimens were sectioned buccolingually in the longitudinal axis centering the amalgam restorations, using the disk. The cut specimens were ground with sandpapers (400, 600, 800, 1000 grit), and cleaned for 5 minutes in the ultrasonic cleaner (Brason Co. U.S.A.). In the cut surfaces, the amalgam - tooth interfaces were examined under the scanning electron microscope (JSM, 35C type, JEOL). The obtained results were as follows ; 1. The amalgam-tooth interfaces were reduced more significantly in the Copalite$^{(R)}$ and Scotchbond 2$^{(R)}$ application group than in the control group. 2. In the class I cavities, the Scotchbond 2$^{(R)}$ application group showed the findings similar to the Copalite$^{(R)}$ application group in the cavity floor, and the marginal adaptability was better in the side wall than in the cavity floor. 3. In the class I cavities, the Scotchbond 2$^{(R)}$ application group showed better marginal adaptability in the occlusal margin than in the gingival margin. 4. The marginal adaptability was in the order of the Scothbond 2$^{(R)}$ application group, the Copalite$^{(R)}$ application group and the control group.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.143-148
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• 2016

The aim of research is inducing the optimum proportion of fly ash(FA) and blast furnace slag(BS) for ternary cement. In this research, hence, the fundamental properties of mortar mixtures were evaluated depending on various proportion of FA and BS. The results of the experiment, within the scope of the study, obtained the following conclusions. Flow of the mixtures was increased with addition of binary supplementary cementitious material(SCM), and especially, portion of FA. The air content of the mixtures was increased with addition of binary SCMs, while it was decreased with increased FA content. In the case of unit mass, increased value was obtained due to the increased air content within 25 to 45% of binary SCM content, while it was increased within 65 to 100% of binary SCM up to only 20% of FA content and decreased more than 20% of FA because of the low density of FA. The setting time of the mixtures was delayed with addition of binary SCM and FA. In the case of compressive strength, at 91-day age, the highest value was obtained with 25 and 45% of binary SCM with the proportion of FA to BS of 40 to 60. Therefore, based on the compressive strength, it is considered that the binary SCM content of 25 and 45% with the proportion of FA to BS of 2 : 3 is the most favorable conditions in this research scope.