• Clean Technology
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• v.23 no.2
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• pp.140-147
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• 2017

In this study, we performed numerical simulation for the catalyst regeneration process of diesel desulfurization reactor. We analyzed the changes in regeneration process according to purge gas flow rate, catalyst permeability, reactor size, and heat loss of reactor. We have found that the regeneration process is very much affected by temperature changes whereas it is hardly affected by catalyst permeability and porosity. We also estimated the regeneration time according to purge gas flow rate and initial temperatures and have found that increasing purge gas temperature is more effect for fast regeneration. The present results can be utilized to design a regeneration process of diesel desulfurization reactor for a fuel cell used in ships. Furthermore, the present work also can be used to design low sulfur diesel supply in oil refineries and therefore contribute to the development of clean petrochemical technology.

• KSBB Journal
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• v.23 no.6
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• pp.474-478
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• 2008

UDP-glucose regeneration system using metabolic engineeringis unique and efficient strategy for oligosaccharide synthesis. To exploit the efficient UDP-glucose regeneration system, we introduced four enzymes, which would be important in partitioning the flux of UDP regenerationsuch as UDP-glucose pyrophosphorylase, UDP-Kinase gene, UDP-galactose 4-epimerase, and $\beta$-1, 4-galactasyltrasnsferase, into E. coli AD202. To determine the optimal expression level for UDP-regeneration, LacNAc concentration was compared depending on IPTG concentration. 0.5 mM IPTG induction showed the higher oligosaccharides synthesis. Using metabolic engineering under optimal IPTG induction, LacNAc synthesis of AD202/pQNGLU increased until 16 h and showed the 1.34 mM. This concentration is 10 times higher than that of control strain at same reaction time. Lactose of AD202/pQNGLU showed the maximum synthesis of 0.39 mM at 16 h and showed the 2.6 times higher than that of control strain.

• The Journal of the Korean dental association
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• v.49 no.2
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• pp.95-103
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• 2011

Purpose : The purpose of this study was to identify and assess factors that may contribute to pain of patients undergoing implant surgery. Materials and Methods: A total of 24 patients who underwent implant surgery were included in the study. Each patient's anxiety was measured using Corah's dental anxiety score(DAS) and modified Spielberger's state-trait anxiety inventory(STAI) immediately after the operation. Also, level of pain was measured using visual analog scale(VAS) during the operation and 48 hours after the surgery. The effect of various factors, such as demographic variables, previous dental experiences and operation time were also analyzed. Results: Postoperative pain levels were relatively low than expected. However, DAS and STAI were high among patients, and it showed that patients had anxieties about implant surgery according to DAS and STAI values. The previous dental experience did not affect the pain level, but the duration of surgery and the presence of accompanied advanced surgery did. Conclusion: To reduce patient's pain, proper management of anxiety will be required and careful attention is needed when performing local infiltration.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.165-178
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• 2021

The Urban Regeneration New Deal project, which started in 2017, has become an important means of urban redevelopment. Anyang Myunghak Village Urban Regeneration Project was selected in 2017 and is currently in its 4th year in 2021. During that time, many conflicts have occurred in the project promotion process, and conflicts are expected to occur in the future. The purpose of this study was to find out what kind of conflicts occurred in what form and how the conflicts were resolved through what solutions at each stage by targeting these Myunghak Village urban regeneration project. And through this, the characteristics of the conflict aspects that occurred in the Myunghak Village urban regeneration project(①The occurrence of continuous conflict in the urban regeneration project ②Composed of various conflict subjects and contents ③The role of conflict-related organizations is insufficient, ④The importance of communication with residents in conflicts) and implications for conflict management in future urban regeneration projects(①continual conflict management plan, ②Early formation of the conflict management organization and strengthening its role, ③communication with residents for conflict management, ④customized conflict management for each stage of project implementation) was presented.

• Journal of Korea Multimedia Society
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• v.23 no.3
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• pp.499-507
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• 2020

This paper is one of the types of 'sharing economy', a social economic model that borrows and shares things, spaces, and services from the development of the 4th Industrial Revolution. Through sharing of empty space and time in the city, I would like to suggest a way to reduce the closure of small business owners in order to create jobs, which is one of urban problems in the community. We also build a platform that utilizes the free time and space of buildings through space sharing, one of the types of sharing economy, and provides education programs for start-up education, promotion, marketing, and consulting by matching small business owners with building owners. Therefore, in this paper, by sharing the space and time, the landlord and the small business can share the profits of the small business by reducing the business owner's closure and the job creation plan. Coaching urban regeneration was proposed.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.2
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• pp.33-42
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• 2011

Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.5
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• pp.507-513
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• 2005

Increasing amounts of anthropogenic $CO_2$ emitted to the atmosphere are believed to be a significant factor in global climate change. Hence, the method of chemical absorption has been suggested to separate and recover acid gases such as $CO_2$. In this study, the characteristics of absorption and regeneration of $CO_2$ for the absorbent which adding HMDA (hexamethylenediamine) into AMP (2-amino-2-methyl-1-propanol), hindered amine, was investigated in lab-scale absorption/regeneration reactor. As a result of this study, the removal efficiency of $CO_2$ increased when adding $5.9\%,\;11.7\%\;and\;23.4\%$ HMDA into $30\%$ AMP respectively. Also, the removal efficiency of $CO_2$ increased $6.5\%,\;8.4\%,\;10.3\%$ respectively as compared to AMP alone when the gas flow rate was 7.5 SL/min. In addition, all absorbents used in the study revealed the high stripping efficiency, which was almost $99\%$, at the temperature of $110^{\circ}C$. Thus, the regeneration tower should be operated at $110^{\circ}C$. At this time, the concentration of exhausted $CO_2$ was higher than $99\%$.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.68-76
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• 2006

The minimization of maximum DPF wall temperature and the fast Light-off during regeneration are the targets for the high durability of the DPF system and the high efficiency of regeneration. In order to predict transient thermal response of DPF, one-channel numerical modeling has been adopted. The effect of the ratio of length to diameter(L/D), cell density, the amount of soot loading on temporal thermal response and regeneration characteristics has been numerically investigated under two different running conditions: city driving mode and high speed mode. The results indicate that the maximum wall temperature of DPF increase with increasing 'L/D' in 'High speed mode'. For 'City driving mode', the maximum wall temperature decreases with increasing 'L/D' in the range of $'L/D{\geq}0.6'$. The maximum temperature decreases with increasing cell density because heat conduction and heat capacity are increased. It is also found that the effect of amount of soot loading on light-off time is negligible.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.163-175
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• 2004

This study was performed to evaluate bone formation in the calvaria of rabbit by the concept of guided bone regeneration with titanium mesh membrane and demineralized freeze-dried bone. The animal was sacrificed at 2 weeks, 4 weeks, 8 weeks, and 12 weeks after the surgery. Non-decalcified specimens were processed for histologic analysis. 1. The titanium mesh but the biocompatibility was excellent the cell-occlusiveness was feeble. 2. The cell-occlusiveness was feeble and also the soft tissue growth of the upper part of the newly-formed bone after operating was excellent in early stage. 3. The maintenance ability of the space for the GBR very was excellent. 4. The titanium mesh the tissue-integration was superior the wound fixation ability excellent. 5. The demineralized freeze-dried bone did not promote the bone regeneration. 6. With the lapse of time, formation quantity of the bone some it increased, it increased quantity very it was feeble. Within the above results, the titanium mesh for the guided bone regeneration was excellent, the dεmineralized freeze-dried bone confirmed does not promote bone regeneration.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.947-953
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• 2017

In this study, the regeneration efficiency of the amino acid salt absorbent which can be applied to carbon dioxide absorption / regeneration process was confirmed. The regeneration efficiency has a great influence on the economical judgment of the process. so, continuous regeneration experiment was conducted to establish economical process. The amino acid salts used in the experiments are Potassium L-lysinate and Potassium L-alaninate. Each amino acid and potassium hydroxide(KOH) were mixed at a 1: 2 molar ratio. In order to confirm the regeneration efficiency of the absorbent, carbon dioxide was absorbed in the two materials, and the carbon dioxide desorption experiment was carried out by heating. The initial reaction rate was L-alanine was faster. Over time, L-lysine, desorption higher concentrations of carbon dioxide. L-lysine showed higher regeneration efficiency than L-alanine, (L-alanine 47.26% and L-lysine 62.11%). As a result of the continuous regeneration experiment using the L-lysine having good absorption and regeneration efficiency, it was confirmed that the regeneration efficiency decreases as the number of regeneration increases.