• International journal of advanced smart convergence
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• 제7권1호
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• pp.42-47
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• 2018

Recently, as the demand for limited resources continues to rise and problems of resource depletion rise worldwide, the importance of renewable energy is gradually increasing. In order to solve these problems, various methods such as energy conservation and alternative energy development have been suggested, and biogas, which can utilize the gas produced from biomass as fuel, is also receiving attention as the next generation of innovative renewable energy. New and renewable energy using biogas is an energy production method that is expected to be possible in large scale because it can supply energy with high efficiency in compliance with energy supply method of recycling conventional resources. In order to more efficiently produce and manage these biogas, a biogas plant has emerged. In recent years, a large number of biogas plants have been installed and operated in various locations. Organic wastes corresponding to biogas production resources in a biogas plant exist in a wide variety of types, and each of the incoming raw materials is processed in different processes. Because such a process is required, the case where the biogas plant process is inefficiently operated is continuously occurring, and the economic cost consumed for the operation of the biogas production relative to the generated biogas production is further increased. In order to solve such problems, various attempts such as process analysis and feedback based on the feedstock have been continued but it is a passive method and very limited to operate a medium/large scale biogas plant. In this paper, we propose "CNN-based production yield prediction algorithm for increasing process efficiency of biogas plant" for efficient operation of biogas plant process. Based on CNN-based production yield forecasting, which is one of the deep-leaning technologies, it enables mechanical analysis of the process operation process and provides a solution for optimal process operation due to process-related accumulated data analyzed by the automated process.

• 대한방사성의약품학회지
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• 제8권2호
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• pp.87-93
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• 2022

[¹⁸F]FDG is known as the most widely used radiopharmaceutical in the imaging field of nuclear medicine worldwide. With the introduction of PET equipment, the demand for [¹⁸F]FDG has increased and the production volume has also increased. However, in order to increase production, the use of ¹⁸F radioisotope must be increased or [¹⁸F]FDG must be synthesized in high yield. Therefore, in order to meet the high yield and purity of radiopharmaceuticals, a radiopharmaceutical automatic synthesizer was required. As the use of [¹⁸F]FDG increased, automated synthesizer manufacturers supplied various types of radiopharmaceutical automated synthesizers to the market. In this study, we developed a commercialized [¹⁸F]FDG radiopharmaceutical automatic synthesizer (sCUBE FDG) using a disposable cassette type that complies with GMP developed by FutureChem, a leading radiopharmaceutical company. We used sCUBE FDG to verify the production process, radiopharmaceutical's quality (radiochemical purity, etc.), and radiochemical yield of [¹⁸F]FDG. As a result of optimizing the automatic synthesis process and synthesizing a total of 30 times, the production time was 35 ± 3 minutes and the average production yield was 65.6%.

• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.215-218
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• 2007

In this paper, amorphous semiconductor and insulator thin film are etched using reactive ion etcher. At that time, we experiment in various RIE conditions (chamber pressure, gas flow rate, rf power, temperature) that have effects on quality of thin film. The using gases are $CF_4,\;CF_4+O_2,\;CCl_2F_2,\;CHF_3$ gases. The etching of a-Si:H thin film use $CF_4,\;CF_4+O_2$ gases and the etching of $a-SiO_2,\;a-SiN_x$ thin film use $CCl_2F_2,\;CHF_3$ gases. The $CCl_2F_2$ gas is particularly excellent because the selectivity of between a-Si:H thin film and $a-SiN_x$ thin film is 6:1. We made precise condition on dry etching with uniformity of 5%. If this dry etching condition is used, that process can acquire high yield and can cut down process cost.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.75-80
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• 1997

This research has been examined to measure the degree of the fiber damage of ozonenation high yield pulp in the beating process. Ozone treated the TMP(Thermomechanical Pulp) and CTMP(Chemithermomechanical Pulp) of spruce and the CTMP of birch has been beaten to be reached 200ml(freeness) of its content. It had been studied the forming of fiber distribution by treatment for long fiber, short fiber, fine with the above method. As ozone treatment time gets longer, the pulp has showed the tendency of increasing the fiber content of 28, 48mesh. Ozone treated fiber has been increased long fiber content by being added softness. By given longer ozone treatment time, the TMP and CTMP of spruce has showed the decreasing of fiber content. On the contrary, CTMP of birch has showed the increasing its fiber content. It had proved that the results of difference are rather closer to the species of tree than closer to the kinds of pulp. The fiber content of over 200mesh which has created in beating process demonstrates the decreasing of its fiber content by getting longer ozone treatment time. The softness of fiber can be extracted by the lignin of fiber surface that had been formed by ozone treatment. Thus we assume that the fiber in the process of beating obtains less physical damage.

• 한국분말재료학회지
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• 제11권4호
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• pp.333-340
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• 2004

In this study, tantalum powder has been producted by MR-EMR combination process. MR-EMR combination process is a method that is able to improve demerits of MR(metallothermic reduction) and EMR(electronically mediated reaction) process. This study examined the characteristics of powder with the amount of reductant excess using $K_2$TaF$_{7}$ as feed materials, Na as a reductant and KCl/KF as a diluent. In addition, this study examined acid treatment that affect the high purification of powder. The impurities contained in powder was removed in various conditions of acid treatment. The total charge passed through external circuit and average particle size(FSSS) were increased with increasing amount of sodium excess. The proportion of fine particle(-325mesh) was decreased with increasing amount of sodium excess. The yield was improved from 70％ to 76% with increasing amount of sodium excess. Considering the impurities, charge, morphology, particle size and yield, an amount of sodium excess of 10wt% were found to be optimum conditions for MR-EMR combination process.s.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.69-72
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• 2005

The crystal structure of magnesium is hexagonal close-packed (HCP), so its formability is poor at room temperature. But formability is improved in high temperature with increasing of the slip planes. Purpose of this paper is to know about the mechanical properties of magnesium alloy (AZ31B), before warm and hot forming process. The mechanical properties were defined by the tension and compression tests in various temperature and strain-rate. As the temperature is increased, yield${\cdot}$ultimate strength, K-value, work hardening exponent (n) and anisotropy factor (R) are decreased. But strain rate sensitivity (m) is increased. As strain-rate increased, yield${\cdot}$ultimate strength, K-value, and work hardening exponent (n) are increased. Also, microstructures of grains fine away at high strain-rate. These results will be used in simulations and manufacturing factor for warm and hot forming process.

• KSBB Journal
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• 제29권1호
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• pp.22-28
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• 2014

In this study, we investigate the effect of pretreatment method on lipid extraction from Enteromorpha intestinalis using physical, thermo-chemical, and enzymatic process such as ultrasonication, high temperature treatment, freezing, microwave irradiation, osmotic shock, pH shock, homogenizing, and enzymatic treatment. In pretreatment with separated lipid extraction, the high extraction yield was obtained by high temperature treatment ($121^{\circ}C$ for 5 min) with 0.1 N HCl, which is 1.4 times higher than that of control. In pretreatment with direct lipid extraction, the high extraction yields were obtained by 0.1 N HCl pretreatment, microwave irradiation (700W, 1 min with twice), and 10% NaCl pretreatment, which is 1.45 times higher than that of control. In the result of enzymatic pretreatment with 17 kinds of enzymes, Cellic CTec II showed the high extraction yield of 5.3%, and which is 1.9 times higher than that of control. Moreover, the extraction yield was increased by the increase of enzyme amounts. In 10% enzyme amount, about 5.8% yield was obtained.

• 펄프종이기술
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• 제34권4호
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• pp.22-29
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• 2002

This research was conducted to investigate the morphological characteristics of fine fibers produced during beating process of high yield pulp treated with ozone and the distribution of lignin in the produced fine fibers. Thermomechanical(TMP) pulp and chemithermomechanical(CTMP) pulp of spruce and CTMP of white birch were beaten to reach 200$m\ell$ CSF, and then the fine fibers were observed using ultraviolet microscope. The fine fibers produced from TMP and CTMP of spruce using treated with ozone for 15 minutes were fragments of fiber surfaces or cell corners, and most of them contained lignin. However, lignin was not observed in the fibers after 15 minutes of ozone treatment. The fine fibers produced from CTMP of white birch were broken pieces or fragments of fiber surfaces or cell corners. The lignin was observed in the fibers until 5min of ozone treatment but no lignin was observed after 5 minutes of ozone treatment. Different morphological characteristics of TMP and CTMP explained both the different morphological characteristics and the distribution of lignin observed in the fine fibers produced from the beating process of TMP and CTMP treated with ozone.

• Industrial Engineering and Management Systems
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• 제7권2호
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• pp.101-112
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• 2008

As charts to monitor the process fraction defectives, P, in the high-yield processes, Mishima et al. (2002) discussed a synthetic chart, the Synthetic CS chart, which integrates the CS (Confirmation Sample)$_{CCC(\text{Cumulative Count of Conforming})-r}$ chart and the CCC-r chart. The Synthetic CS chart is designed to monitor quality characteristics in real-time. Recently, Kotani et al. (2005) presented the EWMA (Exponentially Weighted Moving-Average)$_{CCC-r}$ chart, which considers combining the quality characteristics monitored in the past with one monitored in real-time. In this paper, we present an alternative chart that is more superior to the $EWMA_{CCC-r}$ chart. It is an integration of the $EWMA_{CCC-r}$ chart and the CCC-r chart. In using the proposed chart, the quality characteristic is initially judged as either the in-control state or the out-of-control state, using the lower and upper control limits of the $EWMA_{CCC-r}$ chart. If the process is not judged as the in-control state by the $EWMA_{CCC-r}$ chart, the process is successively judged, using the $EWMA_{CCC-r}$ chart. We compare the ANOS (Average Number of Observations to Signal) of the proposed chart with those of the $EWMA_{CCC-r}$ chart and the Synthetic CS chart. From the numerical experiments, with the small size of inspection items, the proposed chart is the most sensitive to detect especially the small shifts in P among other charts.

• 한국응용과학기술학회지
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• 제24권4호
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• pp.383-392
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• 2007

This paper is studied on the efficient purification process of dimethyl carbonate (DMC) from the melt layer crystallization combining crystallization process, sweating process and distillation recovery process. Purity and yield of DMC crystal depended mainly on the crystallization temperature, cooling rate, sweating termperature sweating rate. Through the optimization of crystallization and sweating operation, DMC crystal can be upgraded to very high purity over 99.9% and high yield over 85%.