• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.757-763
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• 2000

It is fundamental to control individual condition of every seedling. Automatic individual control is used by data control and analysis at on-line. As a result the best condition system was build without all waste. This system uses one of new technology irrigation system. This irrigation system supply accurate quantity of nutrient solution in the shortest time. The system named the upward injection irrigation system. First of all it is necessary to be considered whether the soil is proper or improper for upward injection irrigation system. It is important that root absorb nutrient solution as fast as possible. The ability of spreading, storing water, contamination of environment and cost were considered when choose the medium. The soil of organic culture is developed recently. The soil consists of paper pulp and vermiculite. The new soil is more suitable than ordinary medium for growing plant because this medium is made of paper pulp. The ability of store and spread of water is it's feature. We can make paper tray of this paper pulp's raw material. It is possible that pulp tray replaced plastic tray. The original plug tray of growing seedling system can make which consist of pulp medium and pulp tray. In this study, it was examined whether the plug seedling of paper pulp medium grow with upward injection irrigation system in this seedling plant system. At the same time, examine ability of store and spread of water and how to grow plant on the paper pulp medium.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.1
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• pp.83-95
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• 2020

The economic issue of the period of return versus investment has emerged to efficiently utilize the thermal energy of public resource recovery facilities using waste and private thermal source facilities using BIO-SRF. Accordingly, the optimum temperature and pressure facilities are required beyond the traditional designed, constructed and operated. In this study, we analyzed current energy output by different heat and pressure model in domestic facilities, and calculated the characteristics of green-house gas emission. In order to, utilize the thermal energy producing facilities using waste and biomass fuel more efficiently, it is temperature and pressure, which will lead to more lucrative investment and return as well.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.253-262
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• 2004

Construction of tunnels in a deep crystalline host rock for a potential High-Level Radioactive Waste(HLW) repository inevitably generates an excavation disturbed zone (EDZ). There have been a series of debates on whether a permeability in an EDZ increases or not and what would be the maximum depth of an EDZ. Recent studies show mixed opinions on permeability. However, there has been an international consensus on the thickness of an EDZ; 30 cm for TBM and 1 meter for controlled blast. One of the impacts of an EDZ is on determining the distance between adjacent deposition holes. The void gap by the excavation hinders relaxation of temperature profiles so that the current Korean reference designing distance between holes should be stretched out more to keep the maximum temperature in a buffer region below 100 degrees Celsius. The other impact of an EDZ is on the long-term post closure radiological safety. To estimate the impact, the reference scenario, the well scenario, is chosen. Released nuclides diffuse through a bentonite buffer region experiencing strong sorption and reach a fracture surrounded by a porous medium. Inside a fractured porous region, radionuclides migrate by advection and dispersion with matrix diffusion into a porous medium. Finally, they reach a well assumed to be a source of potable water for local residents. The annual individual dose is assessed on this well scenario to find out the significance of an EDZ. A profound sensitivity study was performed, but all results show that the impact is negligible. Even though the role of an EDZ turns out to be limited on overall safety assessment, still it is worthwhile to study the chemical role of an EDZ, such as a potential source for natural colloids, potential sealing of an open fracture by fine clay particles generated by the process of an EDZ, and alteration of a sorption mechanism by an EDZ in the future.

• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.184-189
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• 2003

This research was conducted to determine the effect of mixing ratio of aquafarm waste water sludge (AWWS) in the growing medium as a source of fertilizers on growth of plug seedlings of pepper (Capsicum annuum L.) and tomato (Lycopersicum esculentum Mill.). Increased mixing ratio of AWWS resulted in increased fresh and dry weights, leaf area, plant height, and total chlorophyll content, although there were slight differences in growth characteristics at 20 and 40 days after sowing. Concentration of AWWS affected insignificantly the percent dry matter, number of leaves, and length of the longest root. The addition of AWWS increased pH and decreased EC in the medium as compared to that of chemical fertilizer. Compared to the control of a liquid fertilizer, 4 or 8 kg AWWS${\cdot}45L^{-1}$ medium (Sludge 4) gave a similar or slightly better growth. Above results suggested that addition of about 4 kg AWWS${\cdot}45L^{-1}$medium is sufficient for seedling growth and the AWWS can be used as a substitute for the liquid fertilizer in plug seedling production.

• International Journal of Concrete Structures and Materials
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• v.6 no.3
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• pp.145-153
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• 2012

The aim of this study is to explore the possibility of re-cycling a waste material that is now produced in large quantities, while achieving an improvement of the mechanical properties and durability of the mortar. This study examines the mechanical properties and the durability parameters of mortars incorporating plastics bag wastes (PBW) as fine aggregate by substitution of a variable percentage of sand (10, 20, 30 and 40 %). The influence of the PBW on the, compressive and flexural strength, drying shrinkage, fire resistance, sulfuric acid attack and chloride diffusion coefficient of the different mortars, has been investigated and analyzed in comparison to the control mortar. The results showed that the use of PBW enabled to reduce by 18-23 % the compressive strength of mortars containing 10 and 20 % of waste respectively, which remains always close to the reference mortar (made without waste). The replacement of sand by PBW in mortar slows down the penetration of chloride ions, improves the behavior of mortars in acidic medium and improves the sensitivity to cracking. The results of this investigation consolidate the idea of the use of PBW in the field of construction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.2
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• pp.187-197
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• 1996

A computer program for thermal design analysis has been developed to predict the operating characteristics and performance of an absorption heat pump to recover $30{\sim}40^{\circ}C$ of waste hot water. The effects of heat transfer area of the system components, temperature and mass flow rate of heat transfer medium, and solution circulation rate on the system performance are investigated in detail. The results obtained indicate that the COP is increased with a decrease in the temperature of driving steam and with an increase in the temperature of waste hot water while the COP is little affected by the variation of a hot water temperature. It is also found that the heating output is increased with an increase in the temperature of waste hot water and driving steam as well as with a decrease in the temperature of hot water. The simulation results are also compared with the experimental results for a periodic operation of the system and obtained a satisfactory agreement.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.1-11
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• 2007

To evaluate the quality of waste paper used for the manufacture of linerboard, the types of papers and foreign materials in compressed waste paper currently used were investigated. The recycled fibers were obtained from printing paper, newspaper, wrapping paper, white coated paperboard and corrugated container. Their fibers were observed by using a microscope, and the mechanical properties of the recycled papers manufactured from the recycled fibers were investigated. The compressed wastepaper was composed of 54% paperboard, 20% printing paper, and 20% newsprint. The content of foreign materials was about 4%, showing higher contents compared to 1% of foreign substances provided by Korea paper manufacturers' association. The types of foreign materials were various, which include vinyls, plastics, metals, woods, styrofoams, and cloths. Sound fibers were generally observed in the recycled fibers of printing papers and wrapping paper. The recycled fibers of white coated board, corrugated container and newsprint showed to be generally damaged. The whiteness of each recycled fiber were highly affected by pulp bleaching and ink-particle mixing conditions. The values of breaking length and burst index were lower than those for corrugating medium and liner board specified in KS. Although the anatomical characteristics of recycled fibers varied, their strengths appeared to be similar. This result may be explained by the use of non-deinked fiber.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.105-112
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• 2004

A waste container, one of the key components of a multi-barrier system in a potential high level radioactive waste (HLW) repository in Korea ensures the mechanical stability against the lithostatic pressure of a deep geologic medium and the swelling pressure of the bentonite buffer. Also, it delays potential release of radionuclides for a certain period of time, before it is corroded by intruding impurities. Even though the material of a waste container is carefully chosen and its manufacturing processes are under quality assurance processes, there is a possibility of initial defects in a waste container during manufacturing. Also, during the deposition of a waste container in a repository, there is a chance of an incident affecting the integrity of a waste container. In this study, the appropriate Features, Events, and Processes(FEP's) to describe these incidents and the associated scenario on radionuclide release from a container to the biosphere are developed. Then the total system performance assessment on the Initial waste Container Failure (ICF) scenario was carried out by the MASCOT-K, one of the probabilistic safety assessment tools KAERI has developed. Results show that for the data set used in this paper, the annual individual dose for the ICF scenario meets the Korean regulation on the post closure radiological safety of a repository.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.231-238
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• 2005

On the basis of flow resistance theory the conceptual model and related mathematical descriptions is proposed for resistance modeling of groundwater flow in CPM(continuum Porous medium), DFN(discrete fracture network) and fractured-porous medium. The proposed model is developed on the basis of finite volume method assuming steady-state, constant density groundwater flow. The basic approach of the method is to evaluate inter-block flow resistance values for a staggered grid arrangement, i.e. fluxes are stored at cell walls and scalars at cell centers. The balance of forces, i.e. the Darcy law, is utilized for each control volume centered around the point where the velocity component is stored. The transmissivity (or permeability) at the interface is assumed to be the harmonic average of neighboring blocks. Flow resistance theory was utilized to relate the fluxes between the grid blocks with residual pressures. The flow within porous medium is described by three dimensional equations and that within an individual fracture is described by a two dimensional equivalent of the flow equations for a porous medium. Newly proposed models would contribute to develop flow simulation techniques with various matrix characteristics.

• Plant Resources
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• v.3 no.2
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• pp.105-109
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• 2000

This study was carried out to find a useful mushroom at Chungnam Agricultural Research And Extention Service. Twenty materials used were collected from domestic and exotic area. These races were compared bontanical characteristics to leading varieties by PCR-RAPD methods. Mycelial growth temperature of Chongpung and Myongwol were at 20 to 25 $^{\circ}C$ and 25 to 30 $^{\circ}C$ at PDA medium, respectively mycelial growth of these varieties were similiar at pH 6.5 to 7.5. In case of mushroom cultivation temperature ranges, Chongpung was at 5 to 26$^{\circ}C$ and Myongwol was at 7 to 28$^{\circ}C$, but the optimum temperature range of these were appeared at 15 to 19$^{\circ}C$. Culture temperature of these was 23$^{\circ}C$ and period of mycelial culture was needed 23 to 24 days under 850cc/pp, while was needed 11 to 12 days at waste cotton medium. Cap color of these at first inducing mushroom was all dark blue, but at late growing stages Chongpung was shown as grey, and Myongwol was shown as dark grey. Yield of Chongpung was appeared as 46kg/3.3$m^2$ and that of Myongwol was 41kg /3.3$m^2$, while Chunchu No2 as check was 40kg/3.3$m^2$. Results from PDA medium and PCR-RAPD analysis two of these were different from others.