• Journal of Environmental Impact Assessment
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• v.19 no.6
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• pp.607-615
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• 2010

Urban green space is often at the centre of the debate on urban substantiality because it provides functions of space, e.g. for wildlife, recreation, growing vegetables, psychological wellbeing, social interaction, etc. Traditionally, the various functions of urban green spaces clearly show that green spaces contain important values that contribute to the overall quality of urban life. After Kyoto protocol, it has becoming important to more accurately evaluate carbon uptake by urban green space. Many studies have analyzed the benefits, costs, and carbon storage capacity associated with urban green space. These studies have been limited by a lack of research on urban tree biomass and carbon uptake by soil, such that estimates of carbon storage in urban systems. This study calculate more accurately the amount of carbon uptake by urban green space. This study also complement the existing methods to estimate the urban green space carbon uptake. It has been studied how to evaluate carbon uptake function of urban green space. The surface area of urban green space increased 5% by complemented method and carbon uptake is also increased. Based on this result, the carbon uptake per capita was analysed and compared to the area of carbon uptake. And this study discussed the reasons for the differences between the new and earlier estimates, as well as implications for our understanding of the global carbon cycle. In conclusion, these results could contribute as preliminary data to policy makers when climate change adaptation strategy is established.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.167-185
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• 2016

$CO_2$ 지중저장 기술은 가장 유력한 대용량 온실가스 감축기술의 하나이다. 이 기술을 적용하여 국제적으로 노르웨이, 알제리, 캐나다, 미국 등에서 이미 대규모 실증 및 상용화 사업이 수행되고 있으며, 호주, 일본, 네덜란드, 독일 등 그 밖의 여러 나라에서 다양한 내용과 규모를 갖는 중소규모 실증사업이 진행되고 있다. 한국도 소규모 육상 파일럿 저장 프로젝트와 중규모 해상 저장실증 프로젝트가 추진되어 착실하게 기술개발과 경험확보를 위해 노력하고 있다. $CO_2$ 지중저장 사업은 화석연료의 사용이 다른 에너지원으로 대체되기 전까지 지속적으로 확장될 것으로 예측되고 있으나, 온실가스 감축시장의 불안전성, 사업의 수익구조와 관련된 경제성, 누출에 대한 안전성 등의 위협요소를 갖고 있다. 따라서 이러한 위협을 극복하기 위해 많은 국가와 기업들이 저비용-고효율 지중저장 기술과 안전한 지중저장 기술의 확보를 목표로 연구개발 및 실증사업을 추진하고 있다. 한국의 경우에 저장소가 주요 포집원으로부터 상당한 거리를 갖고 있는 해저에 발달하고 있기 때문에 지중저장 사업의 경제성 확보가 매우 불리한 조건이다. 따라서 정부나 기업이 CCS 기술을 주요 온실가스 감축수단으로 채택하여 대규모 지중저장 사업을 본격적으로 착수하는 것을 주저하고 있다. 한국과 같은 불리한 조건을 갖는 국가의 경우에 특히 대규모 저장소의 확보를 포함한 저비용-고효율 지중저장 기술의 실용화가 절실하게 필요하다. 결론적으로 한국의 $CO_2$ 지중저장 사업의 성공적인 추진을 위해서는 대규모 저장소의 확보, 저비용-고효율 지중저장 기술의 개발과 실증을 통한 실용화, 중소규모 지중저장 실증사업으로 축적한 기술과 경험으로 대규모 지중저장 사업의 효율화 달성이 요구된다. 이를 위한 실천적인 로드맵과 프로그램의 작성과 착실한 이행 역시 중요하다. 이러한 기반이 착실하게 다져질 경우에 한국에서 대규모 CCS 통합실증과 $CO_2$ 지중저장 사업이 본격적으로 개시될 수 있을 것이다.

• Journal of Pharmaceutical Investigation
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• v.41 no.3
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• pp.125-142
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• 2011

Solid dispersion, defined as the dispersion of one or more active ingredient in a carrier or matrix at solid state, is an efficient strategy for improving dissolution of poorly water-soluble drugs for enhancement of their bioavailability. Compared to other conventional formulations such as tablets or capsules, solid dispersion which can be prepared by various methods has many advantages. However, despite numerous studies which have been carried out, limitations for commercializing these products remain to be solved. For example, during the manufacturing process or storage, amorphous form of solid dispersion can be converted into crystalline form. That is, the dissolution rate of solid dispersion would continuously decrease during storage, resulting in a product of no value. To resolve these problems, studies have been conducted on the effects of excipients. In fact, modification of the solid dispersions to overcome these disadvantages has progressed from the first generation to the recent third generation products. In this review, an overview on solid dispersions in general will be given with emphasis on the various manufacturing processes which include the use of polymers and on the stabilization strategies which include methods to prevent crystallization.

• Journal of Information Technology Applications and Management
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• v.20 no.2
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• pp.57-68
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• 2013

Recently, cloud computing has been viewed as a technology of great influence. Despite the importance of personal cloud services, the majority of cloud computing studies has been focused on an enterprise level. Therefore, in this research, we list variables of personal cloud computing characteristics (accessibility, storage, trust, perceived ease of use, availability) from preceding research done on an enterprise level. So, through pilot testing, we analyze whether examined characteristic variables affect the intention to use personal cloud computing. Next, we investigate the relevancy between user characteristics, including gender, age, and occupation, and the usage rate of personal cloud computing. Lastly, we implement an analysis of variance in order to speculate whether there is any difference between the five characteristic variables in using personal cloud computing between cloud service enterprises. For empirical testing people with experience in personal cloud computing are surveyed. Frequency analysis, exploratory factor analysis, internal consistency analysis, T-test, ANOVA, and multiple regression analysis are implemented with 325 valid samples. The analysis results are as follows: First, among user characteristic variables, 'occupation' shows a significant relationship with cloud service usage, Second, between cloud service enterprises, all five characteristic variables of 'Naver N Drive' are thoroughly evaluated and 'Google Drive' receives a high evaluation in availability and accessibility. Third and finally, all of the selected characteristic variables affect the intention to use personal cloud computing. However, availability is identified to be the most important factor. This research will serve as a reference to enterprises for the practical implementation of personal cloud computing service.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.114-123
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• 1985

This is the second part of the four-part paper describing the development of a packet-switched computer network named the cORNET In this paper, following the first par paper that describes the concepts of the KORNET and the development of the network management center (NMC), wc present the design of the KORNET and the development of the network node processor (NNP) The initial configuration of the KORNET consists of three NNP's and one NMC. We have developed each NNP as a microprocessor-based (Mc68000) multiprocessor system, and implemented the NMC using a super-mini computer (Mv/8000) For the KORNET we use the virtual circuit (VC) method as the packet service strategy and the distributed adaptive routing algorithm to adapt efficiently the variation of node and link status. Also, we use a dynamic buffer management algorithm for efficient storage management. Thc hardware of the NNP system has been designed with emphasis on modularity so that it may be expanded esily . Also, the software of the NNP system has been developed according to the CCITT recommendations X.25, X.3, X.28 and X.29.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.364-368
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• 2018

The R2R3-type protein IbMYB1 transcription factor is a key regulator for anthocyanin biosynthesis in the storage roots of sweet potatoes. It was previously demonstrated that the IbMYB1 expression stimulates anthocyanin pigmentation in tobacco leaves, arabidopsis and storage roots of sweet potatoes. In this study, we generated the transgenic potato plants that express the IbMYB1 genes, which accumulated high levels of anthocyanins under the control of either the tuber-specific patatin (PAT) promoter or oxidative stress-inducible peroxidase anionic 2 (SWPA2) promoter. The PAT-MYB1 transgenic lines exhibited higher anthocyanin levels in the tuber than the empty vector control (EV) or SWPA2-MYB1 plants. When combined, our results indicated that overexpression of the IbMYB1 is a highly promising strategy for the generation of transgenic plants with enhanced tissue specific anthocyanin production.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.163-170
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• 2021

Enzyme replacement therapy for lysosomal storage diseases usually requires recombinant enzymes containing mannose-6-phosphate (M6P) glycans for cellular uptake and lysosomal targeting. For the first time, a strategy is established here for the in vitro mannosyl-phosphorylation of high-mannose type N-glycans that utilizes a recombinant Mnn14 protein derived from Saccharomyces cerevisiae. Among a series of N-terminal- or C-terminal-deleted recombinant Mnn14 proteins expressed in Pichia pastoris, rMnn1477-935 with deletion of N-terminal 76 amino acids spanning the transmembrane domain (46 amino acids) and part of the stem region (30 amino acids), showed the highest level of mannosyl-phosphorylation activity. The optimum reaction conditions for rMnn1477-935 were determined through enzyme assays with a high-mannose type N-glycan (Man8GlcNAc2) as a substrate. In addition, rMnn1477-935 was shown to mannosyl-phosphorylate high-mannose type N-glycans (Man7-9GlcNAc2) on recombinant human lysosomal alpha-glucosidase (rhGAA) with remarkably high efficiency. Moreover, the majority of the resulting mannosyl-phosphorylated glycans were bis-form which can be converted to bis-phosphorylated M6P glycans having a superior lysosomal targeting capability. An in vitro N-glycan mannosyl-phosphorylation reaction using rMnn1477-935 will provide a flexible and straightforward method to increase the M6P glycan content for the generation of "Biobetter" therapeutic enzymes.

• Korean Journal of Materials Research
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• v.31 no.2
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• pp.68-74
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• 2021

Zinc-ion Batteris (ZIBs) are recently being considered as energy storage devices due to their high specific capacity and high safety, and the abundance of zinc sources. Especially, ZIBs can overcome the drawbacks of conventional lithium ion batteris (LIBs), such as cost and safety issues. However, in spite of their advantages, the cathode materials under development are required to improve performance of ZIBs, because the capacity and cycling stability of ZIBs are mainly influenced by the cathode materials. To design optimized cathode materials for high performance ZIBs, a novel manganese oxide (MnO2) coated graphite sheet is suggested herein with improved zinc-ion diffusion capability thanks to the uniformly decorated MnO2 on the graphite sheet surface. Especially, to optimize MnO2 on the graphite sheet surface, amounts of percursors are regulated. The optimized MnO2 coated graphite sheet shows a superior zinc-ion diffusion ability and good electrochemical performance, including high specific capacity of 330.8 mAh g-1 at current density of 0.1 A g-1, high-rate performance with 109.4 mAh g-1 at a current density of 2.0 A g-1, and remarkable cycling stability (82.2 % after 200 cycles at a current density of 1.0 A g-1). The excellent electrochemical performance is due to the uniformly decorated MnO2 on the graphite sheet surface, which leads to excellent zinc-ion diffusion ability. Thus, our study can provide a promising strategy for high performance next-generation ZIBs in the near future.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.37-44
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• 2022

Plug-in Hybrid electric vehicles (PHEV) show great potential to reduce gas emission, improve fuel efficiency and offer more driving range flexibility. Moreover, PHEV help to preserve the eco-system, climate changes and reduce the high demand for fossil fuels. To address this; some basic components and energy resources have been used, such as batteries and proton exchange membrane (PEM) fuel cells (FCs). However, the FC remains unsatisfactory in terms of power density and response. In light of the above, an electric storage system (ESS) seems to be a promising solution to resolve this issue, especially when it comes to the transient phase. In addition to the FC, a storage system made-up of an ultra-battery UB is proposed within this paper. The association of the FC and the UB lead to the so-called Fuel Cell Battery Electric Vehicle (FCBEV). The energy consumption model of a FCBEV has been built considering the power losses of the fuel cell, electric motor, the state of charge (SOC) of the battery, and brakes. To do so, the implementing a reinforcement-learning energy management strategy (EMS) has been carried out and the fuel cell efficiency has been optimized while minimizing the hydrogen fuel consummation per 100km. Within this paper the adopted approach over numerous driving cycles of the FCBEV has shown promising results.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.2
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• pp.91-99
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• 2023

Participation in power trading using surplus power is considered a business model active in the domestic energy trade market, but it is limited only if the legal requirements according to the type, capacity, and use of the facilities to be applied for are satisfied. The hydrogen residential demonstration model presented in this paper includes solar power, energy storage system (ESS), fuel cell, and water electrolysis facilities in electrical facilities for private use with low-voltage power receiving system. The concept of operations strategy for this model focuses on securing the energy self-sufficiency ratio of the entire system, securing economic feasibility through the optimal operation module installed in the energy management system (EMS), and securing the stability of the internal power balancing issue during the stand-alone mode. An electric facility configuration method of a hydrogen residential complex demonstrated to achieve this operational goal has a structure in which individual energy sources are electrically connected to the main bus, and ESS is also directly connected to the main bus instead of a renewable connection type to perform charging/discharging operation for energy balancing management in the complex. If surplus power exists after scheduling, participation in power trading through reverse transmission parallel operation can be considered to solve the energy balancing problem and ensure profitability. Consequentially, this paper reviews the legal regulations on participation in electric power trading using surplus power from hydrogen residential models that can produce and consume power, gas, and thermal energy including hybrid distributed power sources, and suggests action plans.