• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.27-32
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• 1997

Continual monitoring of abnormal operating conditions i a key issue in maintaining high product quality and safe operation, since the undetected process abnormality may lead to the undesirable operations, finally producing low quality products, or breakdown of equipment. The statistical projection method recently highlighted has the advantage of easily building reference model with the historical measurement data in the statistically in-control state and not requiring any detailed mathematical model or knowledge-base of process. As the complexity of process increases, however, we have more measurement variables and recycle streams. This situation may not only result in the frequent occurrence of process Perturbation, but make it difficult to pinpoint trouble-making causes or at most assignable source unit due to the confusing candidates. Consequently, an ad hoc skill to monitor and diagnose in plat-wide scale is needed. In this paper, we propose a hierarchical plant-wide monitoring methodology based on hierarchical decomposition and principal component analysis for handling the complexity and interactions among process units. This have the effect of preventing special events in a specific sub-block from propagating to other sub-blocks or at least delaying the transfer of undesired state, and so make it possible to quickly detect and diagnose the process malfunctions. To prove the performance of the proposed methodology, we simulate the Tennessee Eastman benchmark process which is operated continuously with 41 measurement variables of five major units. Simulation results have shown that the proposed methodology offers a fast and reliable monitoring and diagnosis for a large scale chemical plant.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.153-163
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• 1989

The activity changes and biochemical properties of ${\beta}$-gal in tomato fruits during ripening were investigated. The total activity was increased during ripening and three isoenzymes (${\beta}$-gal I, II and III) were purified through DEAE Sephadex A-50 and Sephadex G-100 column chromatography. The activities of ${\beta}$gal isoenzymes (${\beta}$-gal I, II and III) during ripening were 69.8, 31.8 and 170.0 units in mature green phase, while those were 48.7, 88.4 and 136.8 units in Red phase, respectively. As the ripening proceeded the activities of ${\beta}$-gal I and III were some what decreased but the activity of ${\beta}$-gal II was incresed more than 2.8 fold. The optimum pH of ${\beta}$-gal I, II and III were 3.9, 4.2 and 3.9 and the optimum temperature of those were $60^{\circ}C$, $56^{\circ}C$ and $60^{\circ}C$, respectively. All isoenzymes were stable at pH 3.6~6.0 and lost their activity about 50% when it heated at $55^{\circ}C$ for 5 minute. $Mg^{{+}{+}}$-activated the three isoenzymes but $Ca^{{+}{+}}$ and SDS inhibited about 30~40%. $Hg^{{+}{+}}$ inhibited completely. The km value of ${\beta}$-gal I, II and III was 0.36mM, 0.63mM and 0.45mM, reaction rate was rapidly increased until the concentration of substrate was $6.0{\times}10^{-5}M$.

• Korean Journal of Remote Sensing
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• v.27 no.1
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• pp.59-68
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• 2011

The analysis of optimal infiltration path is one of the representative fields in which the GIS technology can be useful for the military purpose. Usually the analysis of the optimal path is done with network data. However, for military purpose, it often needs to be done with raster data. Because raster data needs far more computation than network data, it is difficult to apply the methods usually used in network data, such as Dijkstra algorithm. The genetic algorithm, which has shown great outcomes in optimization problems, was applied. It was used to minimize the detection probability of infiltration route. 2D binary array genes and its crossover and mutation were suggested to solve this problem with raster data. 30 tests were performed for each population size, 500, 1000, 2000, and 3000. With each generation, more adoptable routes survived and made their children routes. Results indicate that as the generations increased, average detection probability decreased and the routes converged to the optimal path. Also, as the population size increases, more optimal routes were found. The suggested genetic algorithm successfully finds the optimal infiltration route, and it shows better performance with larger population.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.21-26
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• 2011

Differences among cultivars, conditions of nutrient solution, nursing materials, and soilless culture systems were investigated to select suitable cultivar and cultivation methods for stable production of summer spinach in the highlands. The 'Quinto' spinach showed the earliest growth and highest yield. For yield increase of summer spinach, optimal solution pH was 6.0, EC was $2.0dS{\cdot}m^{-1}$, and $NH_4-N$ ratio of nutrient solution was 30 percent Stand rate of spinach in nursing seedlings, at 200-cell-tray filled with mixed nursing soil (peat : perlite = 7 : 3), was higher than those grown in urethane sponge and rock-wool plug. Yield was also 18 to 24 percent higher than those in rock-wool plug and urethane sponge. Plant length and yield of spinach in mixed substrate (peat : perlite = 7 : 3) filled nutrient film technique (MSNFT) system were longer of 18 percent, and higher of 9 percent than those in deep flow technique (DFT) system, respectively. However, changes of root zone temperature, pH and EC showed similar pattern with DFT. Therefore, growing 'Quinto' cultivar at 6.0 of pH, $2.0dS{\cdot}m^{-1}$ of EC, 30 percent of $NH_4-N$ ratio, at 200-cell-tray filled with mixed nursing soil, and MSNFT cultivation system, was the best for production of summer spinach in the highlands.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.348-351
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• 2006

Bipolar plate, which forms about 50% of the stack cost, is an important core part with polymer electrolyte membrane in PEMFC. Bipolar plates have been commonly fabricated from graphite meterial having high electrical conductivity and corrosion resistance. Lately, many researchers have concentrated their efforts on the development of metallic bipolar plate and stainless steel has been considered as a potential material for metallic bipolar plate because of its high strength, chemical stability, low gas permeability and applicability to mass production. However, it has been reported that its inadequate corrosion behavior under PEMFC environment lead to a deterioration of membrane by dissolved metal ions and an increase in contact resistance by the growth of passive film therefore, its corrosion resistance as well as contact resistance must be improved for bipolar plate application. In this work, several types of coating were applied to 316L and their electrical conductivity and corrosion resistance were evaluated In the simulated PEMFC environment. Application of coating gave rise to low interfacial contact resistances below $19m{\Omega}cm^2$ under the compress force of $150N/cm^2$. It also made the corrosion potential to shift in the posit ive direct ion by 0.3V or above and decreased the corrosion current from ca. $9{\mu}A/cm^2$ to ca. $0.5{\mu}A/cm^2$ in the mixed solution of $0.1N\;N_2SO_4$ and 2ppm HF A coat ing layer under potentiostatic control of 0.6V and $0.75V_{SCE}$ for 500 hours or longer showed some instabilities, however, no significant change in coat Ing layer were observed from Impedance data. In addition, the corrosion current maintained less than $1{\mu}A/cm^2$ for most of time for potentiostatic tests. It indicates that high electrical conductivity and corrosion resistance can be obtained by application of coatings in the present work.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.82-89
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• 2013

The phase in digital technology expedited low-budget digital film productions in the Korean film industry; hence the international film festivals circuit became the launching pad for Korean directors as they built their reputation and careers around the critical acclaim. Pieta (Kim Ki-Duk)'s Claim on Golden Lion prize at the Venice Film Festival in 2012 would be one of the splendid achievements - the festival is considered to be one of the top the international film festival. However, the increased volume of the low-budget digital film productions are not necessarily proportional to the growth in the quality of the productions. The drawbacks to the production system appeared to be the underlying cause. In attempt to approach the issue, this article explores the production system from 2000 until now. It is illustrated that the value chain model has been transformed from general ones into vertical & horizontal integrated ones. A notable example of successful indie bands-around Hongik university area-, as well the analysis on the low-budget hit productions, especially from the mid-2000's, are introduced as the case studies. The strategies that led the success, such as subsidies policy, the tax benefits on investment firms and production companies, and the aid in international film festival submissions on low-budget digital film productions, are thus examined with further suggestions.

• Journal of Conservation Science
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• v.36 no.2
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• pp.123-142
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• 2020

We attempted an experimental study of lost-wax casting to reconstruct the Gilt-bronze pensive Bodhisattva; The main object we aimed to reconstruct was the Korean national treasure No.83, Gilt-bronze pensive Bodhisattva(Maitreya); thus, we scientifically analyzed and measured the alloy ratio and casting method. Initially, the alloy ratio we used during the preliminary experiment was Cu:Sn:Pb = 95.5:4.0:0.5; we then increased tin and lead by 2.5% to consider vaporization during the main experiment. After applying lost-wax casting, we realized that 30% rosin contributed to proper hardness after the wax hardness experiment. The microstructure revealed normal casting character(α-Cu, δ), and the results of the chemical analysis are identical to those of previous studies. The analysis of the mold suggests the presence of quartz powder for structural stability and fire-resistance along with other organic materials whose contribution is still unknown. We expect that our research will serve to provide basic data for advanced studies in the future.

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.9
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• pp.514-526
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• 2004

Microarray is a new technique for gene expression experiment, which has gained biologist's attention for recent years. This technology enables us to obtain hundreds and thousands of expression of gene or genotype at once using microarray Since it requires manual work to analyze patterns of gene expression, we want to develop an effective and automated tools to analyze microarray image. However it is difficult to analyze DNA chip images automatically due to several problems such as the variation of spot position, the irregularity of spot shape and size, and sample contamination. Especially, one of the most difficult problems in microarray analysis is the block and spot addressing, which is performed by manual or semi automated work in all the commercial tools. In this paper we propose a new algorithm to address the position of spot and block using a new concept of regular structure grid searching. In our algorithm, first we construct maximal I-regular sequences from the set of input points. Secondly we calculate the rotational angle and unit distance. Finally, we construct I-regularity graph by allowing pseudo points and then we compute the spot/block address using this graph. Experiment results showed that our algorithm is highly robust and reliable. Supplement information is available on http://jade.cs.pusan.ac.kr/~autogrid.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.135-146
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• 1991

This study was attempted to know the effect of crude extracts of Allium fistulosum on the seed germination and seedling growth in compositae. The result is as follows; The seed germination and seedling growth in the tested compositae were inhibited by the crude extracts from leaf blade, leaf sheath and root of Allium fistulosum. Generally the crude extracts from leaf blade part showed the highest inhibitory effect in the tested parts. The seed germination was inhibited by the crude extracts of Allium fistulosum extracted with 80% methyl alcohol and distilled water. But the crude extracts which had extracted with distilled water indicated more inhibitory effect than that of 80% methyl alcohol. The seedling growth was depressed by the root residues of Allium fistulosum in the soil after harvesting. The crude extracts had the character of stability in light and heat. Some out of the inhibitors contained the volatile substances.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.319-329
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• 2018

With rapid development of technology for strong AI chatbot, the role of chatbot has been extended from conducting simple tasks to being a friend or counsellor. For this newly emerging purpose of chatbot, endowment of personality is important to make the chatbot regarded as a human being. Nevertheless I found that there are few guides about it. Thus, this study identifies the proper personality of chatbot depending on the purpose of services and user types. The purposes of chatbot services are divided into three types such as leisure-time, counselling, and task. The DISC theory is used for categorizing personality, which consists of 4 types such as dominance(D), inducement(I), submission(S), and compliance(C). An interview and survey were conducted to investigate the preferred personality of chatbot and contents for leisure-time. As results, people tend to prefer people-oriented types such as I, S for their leisure time, task-oriented types such as D,C for their task, and slow types such as C,S for counselling. Women prone to prefer neutral gender except for counselling and men tend to prefer female in all chatbot services. Preferred chatbot age is either same or younger age for leisure-time, same or older for counselling, and 30's for tasks. Preferred contents for leisure-time are mostly recent information but many 20's want fun contents and 50-70's want emphatic conversation. 30-50's want honorific but 20's and 60-70's don't care. The research results useful guide on proper personality of AI chatbot for each purpose of its service.