• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.92-101
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• 2012

Korea shows the soil pH is 5.8 ~ 6.2 by many factors including the geological structure and climate condition. There is known as the cause for soil acidification by weathering of the mineral, excessive use of the chemical fertilizer, and extensively diffused acid rain. The purpose of research is environmentally-friendly material neutralization technology development utilizing the waste resources against by acid soil. The experiment analyze the physico-chemical property of the acid soil and waste resource materials (waste lime, oyster shell, bottom ash). The Batch-Test was performed under 3 stage. As a result, the acid soil showed up acid soil about 3.19. And waste lime, oyster, bottom ash showed the alkalinity with 9.62, 10.08, 9.17. In case of 1 batch-test experimental result, waste lime and oyster shell, the alkalinity was shown over 7.5 and the good efficiency was showed, on the other hands, the bottom ash showed the pH 4 the neutralization efficiency which is low. waste resource materials to be applied to 2 steps was chosen as the waste lime except the bottom ash and oyster. In 2 step batch-test experiment, it was exposed to be the most appropriate in case of doing the combination ratio of the waste lime and oyster shell with 9 : 1. It was exposed to be efficient most in the effeciency and aspect of economical efficiency combination ratio of the soil and materials was 9.6 : 0.6 with 3 step batch-test experimental result.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.63-68
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• 1982

This study was aimed ultimately to develop an adsorption process treating heavy metal industrial wastewater by utilizing domestically abundant natural zeolite and the study was conducted in a series of investigations. Presented if1 this paper are the results of the preliminary batch mode test. Factors affecting an adsorption process of heavy metals of aqueous waste stream by zeolite are numerous. Factors such as hydrogen ion concentration and temperature are taken into consideration in the investigation to evaluate adsorptive capacity. The mechanisms of adsorption may better be described by an evaluation of adsorption isotherm andi of adsorption kinetics. It is observed from the preliminary investigation that an optimum adsorption occurs at higher pH's than 4. It is further demonstrated that $Cd^{+2}$ adsorption by zeolite follows the BET model better than the Freundlich and the Langmuir model and that the reaction time of at least 10 minutes is required. It is interesting to note that higher adsorptive capacity was found at higher temperature, suggesting that the adsorption is not only due to simple physisorption but also due to chemisorption.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.4
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• pp.23-32
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• 2020

Many small and medium-sized manufacturing companies process various product types to respond different customer orders in a single production line. To improve their productivity, they often apply batch processing while considering various product types, constraints on batch sizes and setups, and due date of each order. This study introduces a batch scheduling heuristic for a production line with multiple product types and different due dates of each order. As the process times vary due to the different batch sizes and product types, a recursive equation is developed based on a flow line model to obtain the upper bound on the completion times with less computational complexity than full computation. The batch scheduling algorithm combines and schedules the orders with same product types into a batch to improve productivity, but within the constraints to match the due dates of the orders. The algorithm incorporates simple and intuitive principles for the purpose of being applied to small and medium companies. To test the algorithm, two case studies are introduced; a high pressure coolant (HPC) manufacturing line and a press process at a plate-type heat exchanger manufacturer. From the case studies, the developed algorithm provides significant improvements in setup frequency and thus convenience of workers and productivity, without violating due dates of each order.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.3
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• pp.55-63
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• 1996

Nitrification reaction consists of two reactions: nitritification which oxidizes ammonia nitrogen to nitrite nitrogen and nitratification which oxidizes nitrite nitrogen to nitrate nitrogen. Each reaction is carried out by Nitrosomonas and Nitrobacter, respectively. The effective maximum growth rates for both bacteria have to be determined to design aeration tank whenever the aeration tanks have to nitrify ammonia nitrogen in influent. And these values are very important to use mathematical models such as IAWPRC model to simulate nitrification in activated sludge. There are several methods to determine these valves, however, the Fed-Batch experiments can determine these values within 72 hours. In this study, the mathematical equations and experimental procedures for Fed-Batch test are presented. Also, the experimental data and reported values are compared. The estimated mean values of maximum specific growth rates for Nitrosomonas and Nitrobacter are $0.5010day^{-1}$ and $0.6704day^{-1}$, respectively.

• Solar Energy
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• v.7 no.1
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• pp.3-13
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• 1987

A batch type passive solar water systems, which perform the dual function of absorbing the solar energy and storing the heated water, have been designed and fabricated for the purpose of side-by-side testing at KIER. The test models included an A, B and C type batch systems which were classified according to the design of box and arrangement of tanks. The year-round performance tests show that B type batch system taken the step-wise tank arrangement indicates 55.7% yearly-average collection efficiency factor and 61% yearly-average maximum collection efficiency factor. Computer-aided-experimental results show that the sufficient hot water can be obtained in the early morning if the glazing is supplemented by a reflector/insulation cover. The thermal performance equation has been developed for the prediction of hourly variation of the water temperature in tank.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.353-356
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• 2006

Hardening of 2 component adhesive such as epoxy resin used in saturating FRP composite is triggered by mixing each component part within a batch. Chemical reactions occur explosively after a certain time after mixing the batch, viscosity and temperature rapidly increase. As a results, bond performance remarkably decreases and workability declines due to increase in viscosity. Therefore, adhesion should be completed before chemical hardening reaction is rapidly going on. This study examined pot life of structural adhesive for FRP composites by means of change in apparent viscosity and means of exothermic reaction temperature proposing in existing test standards. Result of each test method was compared and analyzed, and reasonable test method and evaluation method are suggested.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.197-204
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• 2007

The reciprocal effects towards the enhanced biological phosphorus removal were performed for anaerobic, aerobic and anoxic phases. The batch experiments showed that the p-absorption in the anoxic phase was 50% lower than aerobic phase. The correlation coefficient between p-back-solution and p-absorption was found to be $R^2=0.557$ however, the coefficient b(b = 8.4049) was relatively higher than the other researchers results. The increase and/or acceptance of the $K^+-,\;Mg^{2+}-$ and $NH_4-N$-concentration was proportional to those of the $PO_4-P$-concentration in the batch test. The relationship between $K^+-,\;Mg^{2+}$ and $PO_4-P$ was determined. The average value of this relation-ship agreed with 0.2 mol $K^+Ion$ / mol $PO_4-P$ ion and 0.21 mol $Mg^{2+}Ion$ / moi $PO_4-P$ ion in the anaerobic phase. The absorbed ratio of $K^+$ to $Mg^{2+}$ over $PO_4-P$ was found to be 1 : 5.

• Journal of Animal Science and Technology
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• v.52 no.6
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• pp.513-519
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• 2010

A series of experiments were performed to study the influence of the following parameters on the physical traits and composition of swine manure compost: (1) addition of magnesium (Mg) at a molar ratio of 1.2 with respect to $PO_4$, and (2) reutilization of compost containing $MgNH_4PO_4{\cdot}6H_2O$ (magnesium ammonium phosphate, MAP). Three independent batch tests were conducted for replication: batch test I-control (C) and Mg added (T), batch test II-C, T and compost recycle ($T_{R1}$), and batch test III-C, T and compost recycle ($T_{R2}$). Magnesium addition and compost reutilization had no adverse effect on the degradation of organic matter. Reuse of the compost, however, had a clear effect on the total nitrogen (TN) and total phosphorus (TP) contents in the final compost. Repeated compost reutilization as a bulking material was resulted in composts rich in N and P. Upon adding the Mg supplement to the composting materials, the ortho-phosphate (OP) to TP ratio decreased due to the MAP crystallization reaction. The decrease in the OP/TP ratio and the increase in the TP content of the compost indicate that water-soluble phosphate is converted into a slow-release phosphate by the formation of crystals during composting. X-ray diffraction analysis of the irregular shaped crystals in the compost indicated that they are MAP crystals and that the crystallization of MAP begins immediately after the addition of the Mg supplement. The Mg addition to composting materials and the reutilization of compost as a bulking material would be a practical means to conserve nutrient content.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.409-418
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• 2017

This work attempted to manufacture glued-laminated timber (Glulam) bonded with melamine-urea-formaldehyde (MUF) resin adhesives at various melamine contents from 20% to 50% under high frequency (HF) heating for a very short time. Two preparation methods were employed to prepare MUF resin adhesives with different melamine contents: one-batch method of synthesizing MUF resins in a single batch, and two-batch method of mixing urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized separately. As the melamine content increased, the gelation time and peak temperature of MUF resins decreased. The adhesion performance of plywood showed that the one-batch MUF resin adhesive with 50% melamine content only satisfied the standard requirement of water resistance. Thus, the one-batch MUF resin adhesive with 50% melamine content was applied for bonding wood lamina from four softwood species such as Japanese larch, Korean red pine, Korean pine and Japanese cedar to manufacture Glulam under HF heating. All Glulam samples bonded with the one-batch MUF resin adhesives with 50% melamine content except those from Korean Red Pine satisfied the requirement in water soaking or boiling water delamination test as an exterior grade Glulam. The presence of rosin in Korean Red Pine was believed to be responsible for its poor adhesion. These results showed that the one-batch MUF resin adhesives with 50% melamine content provided acceptable water resistance with exterior grade Glulam manufactured under HF heating.

• Journal of the Korean GEO-environmental Society
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• v.10 no.7
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• pp.25-32
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• 2009

The main objective of this study was to examine the removal properties of Cu from water by inflated vermiculites. The component of vermiculites was analyzed by XRF and the concentration of Copper ion was measured by UV-VIS. Serial batch Kinetic tests and batch sorption tests were conducted to determine the removal characteristics for Cu in aqueous solutions. The result shows that removal rate, $K_{obs}$, of Cu are 0.73, 1.52, and 1.71 for initial pH 3, pH 4, pH 5, respectively, and are 3.19, 1.90, and 0.73 for the initial concentration of $1mg\;L^{-1}$, $5mg\;L^{-1}$, $10mg\;L^{-1}$, respectively. It leads to the conclusion that the removal rates are inversely proportional to the initial Cu concentration and are increased proportionally to the initial pHs. Finally, Sorption data were correlated with both Langmuir and Freundlich isotherms. As a result, Langmuir and Freundlich models were well fitted to batch isotherm data with good values of the determination coefficient. but the determination coefficient value for the Freundlich model fit was slightly higher than that of Langmuir model (0.965 for the Freundlich model and 0.936 for the Langmuir model). Using the Langmuir model, the maximum sorption capacity ($Q_{max}$), Freundlich partition coefficient, and the numerical value of n wrer estimated as $1,250mg\;kg^{-1}$, $635.1L\;kg^{-1}$ and 1.69, respectively. These results show that the inflated vermiculites could be used as an excellent adsorbent for copper contained in various types of aqueous solutions.