• Environmental Engineering Research
• /
• v.18 no.2
• /
• pp.91-94
• /
• 2013

Recently Ibadan in southwestern Nigeria has been facing severe water shortage due to the increase of population, social and economic activities. In order to meet the shortfall, attempts to utilize rainwater harvesting (RWH) have been made to provide an alternative source of water supply. A desk study was conducted to review various RWH technologies locally, regionally and globally. A hydrological analysis was also carried out using rainfall data for 30 years from two meteorological stations, with the aim of providing a more sustainable RWH system for water supply to private individuals, organizations, and government agencies. RWH is found to be technically feasible based on the prevailing rainfall pattern with over 90% of households having a rooftop constructed from technically appropriate materials. Results of the study indicate that an average roof of $80m^2$ will collect 82,835 L/yr (45 L/person/day) for a family of five people which is about the required water demand for drinking and cooking purposes. Hence, the capacity of storage tanks and the catchment area required for an all-purpose water supply system based on RWH are quite large. These can be reduced to affordable sizes, by collecting and storing water for cooking and drinking only while non-potable uses are supplemented by water from other sources. However, it must be highlighted that due to the type of roofing material, rainwater should go through proper treatment in order to be used for potable purposes. This study clearly shows that Ibadan city has a good rainwater harvesting potential.

• Journal of Conservation Science
• /
• v.7 no.2
• /
• pp.60-67
• /
• 1998

The effects of moisture content (MC) and diffusion period on the diffusion of boron from borate rod through Pinus densiflora and P. koraiensis were investigated as a preliminary research of integrated remedial treatment for heritage wooden structures using borate rod. After equilibrating MCs of samples (15, 25, and 40%), borate rod (1,000 mg) was inserted into the sample, and stored for diffusion of boron at room temperatures ($23^{\circ}C$) for 2, 4, 8, and 12 weeks. Wafers were serially cut at constant intervals from rod treatment point and the boron penetration through longitudinal and transverse direction was measured by staining with boron indicator. For boron diffusion, MC above fiber saturation point was needed, and the diffusion rates increased with time. The fastest rates of diffusion were observed in longitudinal direction, followed by the radial and then the tangential direction. The rates of diffusion in all directions were the fastest in P. koraiensis. In P. densiflora, the diffusion rates through heartwood was faster than that in sapwood in longitudinal direction and vice versa in transverse direction. Based on the best result of this study, optimal space between rod insertion points could be recommended as follows; approximately 120 mm for P. koraiensis and heartwood of P. densiflora, 60 mm for sapwood of P. densiflora in longitudinal direction, and approximately 30 mm for all species tested in transverse direction. However, the effect of rod size and long-term exposure for diffusion on boron movement should be fully investigated for the accurate evaluation of optimal space between rod holes.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.6
• /
• pp.130-142
• /
• 2008

The objective of this study is to analyze the types and current status of development projects that underwent environment assessment in recent three years and provide basic data to encourage environment-friendly development projects in the future. This study was conducted by analyzing the pre-environment review reports and environment impact statements of development projects that took place in Gyeonggi province. Key findings are as follows. First, a total of 2,465 development projects spanning $173km^2$ were undertaken in Gyeonggi province in recent three years. This is equivalent to three times of the area of Anyang city. Second, types of development projects were in the order of factories and industrial parks, road construction, town (housing estates) development, sports facilities and waste treatment facilities. Public projects accounted for about 30%, while private investment projects represented 70%, indicating that private sector projects were as twice as high. The findings of this study show that the development density of Gyeonggi-do should be examined as a whole in order to develop a comprehensive, long-term plan and harmonize conservation and development systematically in Gyeonggi-do in a holistic perspective.

• Journal of computational fluids engineering
• /
• v.17 no.1
• /
• pp.8-15
• /
• 2012

A code developed using the flux-difference splitting scheme on the hybrid Cartesian/immersed boundary method is applied to simulate three-dimensional internal waves. The material interface is regarded as a moving contact discontinuity and is captured on the basis of mass conservation without any additional treatment across the interface. Inviscid fluxes are estimated using the flux-difference splitting scheme for incompressible fluids of different density. The hybrid Cartesian/immersed boundary method is used to enforce the boundary condition for a moving three-dimensional body. Immersed boundary nodes are identified within an instantaneous fluid domain on the basis of edges crossing a boundary. The dependent variables are reconstructed at the immersed boundary nodes along local normal lines to provide the boundary condition for a discretized flow problem. The internal waves are simulated, which are generated by an pitching ellipsoid near an material interface. The effects of density ratio and location of the ellipsoid on internal waves are compared.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.2
• /
• pp.184-192
• /
• 2006

Six-hundred bacterial strains from human milk and milk from Sahiwal cows, Holstein Friesian cows, and buffaloes were screened for their ability to suppress phytopathogenic fungi under in vitro conditions. A consortium of 3 strains, viz., Bacillus lentimorbus B-30486 (B-30486), B. subtilis B-30487 (B-30487), and B. lentimorbus B-30488 (B-30488), isolated from Sahiwal cow milk resulted in better biological control and plant-growth promotion than single-strain treatments. For commercial-scale production of a bioinoculant, the solid-state fermentation of sugarcane agro-industrial residues, i.e., molasses, press mud, and spent wash, using the consortium of B-30486, B-30487, and B-30488, resulted in a value-added product, useful for enhancing plant growth. The application of the consortium to sugarcane fields infested with Fusarium moniliforme and Colletotrichum falcatum resulted in a reduction of mortality and significantly higher (P=0.05) plant height, number of tillers, and cane girth when compared with the control. Furthermore, under field conditions, the treatment of sugarcane with the consortium resulted in significantly (P=0.05) greater plant growth compared with nonbacterized plants. Accordingly, this is the first report on the effective use of bacteria isolated from milk for biological control and enhancing plant growth under field conditions. Furthormore, a solid-state fermentation technology was developed that facilitates the economic utilization of agro-industrial residues for environmental conservation and improving plant and soil health.

• Journal of Biomedical Engineering Research
• /
• v.13 no.3
• /
• pp.181-188
• /
• 1992

This paper provides an overview of system analysis of immunology. The theoretical research in this area is aimed at an understanding of the precise manner by which the immune system controls Infec pious diseases, cancer, and AIDS. This can provide a systematic plan for immunological experimentation by means of an integrated program of immune system analysis, mathematical modeling and computer simulation. Biochemical reactions and cellular fission are naturally modeled as nonlinear dynamical processes to synthesize the human immune system! as well as the complete organism it is intended to protect. A foundation for the control of tumors is presented, based upon the formulation of a realistic, knowledge based mathematical model of the interaction between tumor cells and the immune system. Ordinary bilinear differential equations which are coupled by such nonlinear term as saturation are derived from the basic physical phenomena of cellular and molecular conservation. The parametric control variables relevant to the latest experimental data are also considered. The model consists of 12 states, each composed of first-order, nonlinear differential equations based on cellular kinetics and each of which can be modeled bilinearly. Finally, tumor control as an application of immunotherapy is analyzed from the basis established.

• Journal of Korean Society of Forest Science
• /
• v.104 no.1
• /
• pp.43-49
• /
• 2015

The production of high quality seedlings is a very important phase in silvicultural systems for successful reforestation or restoration. The purpose of this study was to quantitatively measure both growth performances and nutrient responses of Fraxinus rhynchophylla, Pinus densiflora, and Pinus koraiensis seedlings, which are commercially planted in Korea, according to the different types of soil improvement treatments. We applied soil brought (hereafter 'brought'), subsoil inversion (hereafter 'subsoil'), and mixture of brought soil with soil on nursery bed (hereafter 'mixing') in a permanent national nursery. Silt and clay contents were the highest at the subsoil treatment and organic material, soil nitrogen and phosphorus concentrations were the lowest at the brought treatment. The growth of F. rhynchophylla was the lowest at the subsoil treatment, but there were no significant differences among treatments. There were significant differences in only root nutrient concentrations of F. rhynchophylla among treatments: nitrogen, phosphorus, and potassium concentrations were the lowest at the subsoil or brought treatment. Mixing treatment increased N contents with deduction of N concentrations ('dilution') because of more dry weight increase compared with the amount of N uptake. This study suggested mix of brought soil with soil on a nursery bed in a permanently used nursery can economically be an effective technique to improve soil quality.

• Korean Journal of Metals and Materials
• /
• v.50 no.8
• /
• pp.599-603
• /
• 2012

The microstructure of a hammer scale excavated from the Bogam-ri was examined in an effort to understand the iron technologies applied in the manufacturing of an iron forging process technology. The microstructures of oxide layer in the hammer scale were found to have crucial information about the ancient iron forging process treatment. The microstructure observed in the hammer scale can be distinguished by the forging process. First, the microstructure of the oxide layer in the hammer scale created by the forging process is Wstite (FeO) in the form of leaves. Latterly, the microstructure of the $W{\ddot{u}}stite$(FeO) in the hammer scale is observed to be in the form of a flat shape formed by a repeating forging process.

• Journal of Korean Library and Information Science Society
• /
• v.35 no.3
• /
• pp.79-94
• /
• 2004

This research studied the preservation treatment of the papered literature the national treasure 745-9 $\ulcorner$Keumganggyung-samgahae$\lrcorner$, discovered in 1995 from the Four Devas of Borimsa Buddhist Temple at Jangheung County, in the viewpoint of the bibliography. The overall features of the $\ulcorner$Keumganggyung-samgahae$\lrcorner$ were of 25.3cm width, 38.9cm height 1.5cm depth, 58 pages and of high-fine yellow-brown colored reef paper. The book was ruined physically in the shape and color. The covers of the book were deeply stained by the permeated rain and some internal pages were changing into brown color by corrosion. The treatment policies were； maintaining the status quo and capable repeated treatment. And the preservation treatment was done in the sequences of 1) 1st cleaning process, 2) repairing and correcting, 3) 2nd cleaning and preservation 4) cutting, binding the book and making the envelope and wood box. The post-preservation features of $\ulcorner$Keumganggyung-samgahae$\lrcorner$ were； total 64 pages and the size being 25.8 cm width 39.4cm of lenght, and 1.9cm of depth.

• Journal of Conservation Science
• /
• v.31 no.1
• /
• pp.37-46
• /
• 2015

In the case of adhesives & restoration agents currently being used for the preservation treatment of ceramics and earthenware, epoxy type, cellulose type and cellulose type are mainly being used. However, they are showing various problems such as re-detachment from severe contraction, color change from yellowing, work inconvenience of staining on tools and hand during usage and irreversibility. For the purpose of solving the issues of yellowing and irreversibility of epoxy resin being used to restore ceramics, urethane synthetic resin with low yellowing excellent reversibility has been developed in this study. The adhesive strength of urethane resin that has been developed has excellent properties with 2.07MPa for undiluted solution, which is 1.5 times higher than that of existing material EPO-$TEK301^{(R)}$ 1.21MPa. The result of workability measurement showed that the wear rate of urethane resin (in Talc 50wt%) was 1.09%, which was somewhat higher than that of existing material Quick $Wood^{(R)}$ (1.02%). In addition, its wear rate is two times higher than that of $EPO-TEK301^{(R)}$ (0.41%) and $L30^{(R)}$ (0.39%), thereby showing an advantage in its forming process compared to existing materials. As for the advantage of urethane resin of reversibility experiment, 12 hours after acetone, ethyl alcohol deposition, urethane resin and filler talc were dissolved 100% while showing powdering phenomenon. Compared to 0% reversibility of existing epoxy resin, it has much superior reversibility. The result of UV rays experiment to evaluate its durability showed that ${\Delta}E^*ab$ color change value based on undiluted solution of urethane resin was 2.76 before & after UV rays exposure, which was a decrease by about 7-20 times compared to that of existing resin, thereby minimizing the issue of heterogeneity.