• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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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.

• 대한토목학회논문집
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• 제2권1호
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• pp.63-68
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• 1982

본(本) 연구(硏究)는 국산천연(國産天然) 제오라이트를 이용한 중금속(重金屬) 산업폐수(產業廢水) 처리공정(處理工程)을 개발(開發)할 목적(目的)으로 수행(遂行)되었으며 본 논문에서는 1차적으로 알카리 처리된 제오라이트를 이용하여 Batch Test를 통한 기초실험(基礎實驗) 결과(結果)를 수록하였다. 제오라이트에 의한 중금속 흡착(吸着)공정에 미치는 pH의 영향(影響), 흡착 Isotherm Model 결정, 흡착속도 및 온도(溫度)의 영향을 중점적으로 평가분석(評價分析)하였으며 그 결과 최적(最適) pH는 4~5이상, 카드미움 흡착은 BET Model이 적합하며, 반응시간(反應時間)은 10분 이상이 소요됨을 알았으며 또한 온도가 증가하면 비례하여 흡착능(吸着能)도 증가하므로서 단순한 물리흡착(物理吸着)만이 아닌 화학흡착(化學吸着)도 병행하여 일어나고 있다고 판단된다. 본 연구 결과로 판단컨대, 국산 천연 제오라이트를 이용한 중금속 폐수처리는 그 전망이 밝으며 앞으로 Column Test를 통하여 합성(合成)폐수는 물론 실제폐수의 처리도(處理度)를 실험하므로서 처리공정설계 조건을 도출할 수 없으며 이와 같은 공정의 개발로서 우리나라의 중금속 폐수처리에 획기적인 공헌이 기대된다.

• 산업경영시스템학회지
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• 제43권4호
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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.

• 상하수도학회지
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• 제10권3호
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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.

• 태양에너지
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• 제7권1호
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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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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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.

• 대한환경공학회지
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• 제29권2호
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• pp.197-204
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• 2007

이 연구는 EBPR(enhance biological phosphorus removal)의 혐기조건, 호기/무산소 조건 사이의 상호작용을 알아보고 인의 제거 속도와 인 제거에 미치는 영향인자들을 Batch-test로 조사하였다. 실험결과 무산소단계에서 인의 흡수율은 호기 단계보다 50% 정도 낮았고, 인 방출과 인 흡수의 상관관계는 다른 논문들에 비하여 낮았으며, 계수 b는 높았다. Batch-test의 측정 결과 다른 논문들에 비하여 인 방출과 인 흡수의 상관관계$(R^2=0.557)$는 낮았고 계수b (b=8.4049)는 높았다. 또한, 하수에서 인의 중요한 결합 파트너는 Ca, $Mg^{2+}$, Al, Fe 그리고 $K^+$인데 이 실험 결과 칼륨, 마그네슘 그리고 암모니움은 인과 함께 증감함으로써 인의 방출과 흡수에 밀접한 관계가 있음을 알 수 있었다. 즉, 혐기 단계에서 0.2 mol $K^+Ion$ / mol $PO_4-P$ Ion과 0.21 mol $Mg^{2+}Ion$ / mol $PO_4-P$ ion이 측정되어 인에 대한 칼륨 및 마그네슘의 비율은 1 : 5 정도임을 알 수 있었다.

• Journal of Animal Science and Technology
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• 제52권6호
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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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• 제45권4호
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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.

• 한국지반환경공학회 논문집
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• 제10권7호
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• pp.25-32
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• 2009

본 연구는 팽창질석을 사용하여 수용액 상의 구리이온 흡착 제거능을 평가 하고자 하였다. 질석의 화학적 조성분석은 XRF, 구리이온 농도분석은 UV-VIS를 각각 사용하여 이루어졌다. 수용액 상의 구리이온의 제거양상을 살펴보기 위해 batch kinetic test와 batch sorption test가 실시되었고, 그 결과 구리의 제거속도($K_{obs}$, 1/hr)는 초기pH 3일때 0.73, pH 4일때 1.52, pH 5일때 1.71였고 초기농도가 $1mg\;L^{-1}$ 일때 3.19, 5일때 1.90, 10일때 0.73으로 초기구리농도와 반비례하고 초기 pH와는 비례하여 증가하는 양상을 보였다. 하지만 초기용액의 농도차이보다 초기pH의 영향이 지배적일 것이라는 예상하에 동일한 농도에 pH만 달리하여 실험해본 결과 역시 예상대로 pH에 따라 제거속도가 크게 차이남을 알 수 있었다. 최종적으로 batch sorption test를 통해 얻은 결과를 각각 Freundlich와 Langmuir 등온흡착식에 대입한 결과 두 식 모두 양호한 fitting 결과를 얻을 수 있었으나 Freundlich 식의 결정계수가 0.965로 Langmuir 식의 결정계수 0.936보다 좀 더 높게 나타나 좀 더 정확한 fitting 결과를 보여주었다. Langmuir 모델로부터 얻은 최대흡착용량($Q_{max}$), Freundlich 모델의 분배계수, n 값은 각각 $1,250mg\;kg^{-1}$, $635.1L\;kg^{-1}$, 1.69였다. 이러한 결과는 팽창질석이 다양한 형태의 수용액 상에 존재하는 구리이온을 효과적으로 제거할 수 있음을 보여준다.