• Korean Journal of Optics and Photonics
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• v.20 no.3
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• pp.175-181
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• 2009

Holographic lithography is one of the potential technologies for next generation lithography which can print large areas (6") as well as very fine patterns ($0.35{\mu}m$). Usually, photolithography has been developed with two target purposes. One was for LCD applications which require large areas (over 6") and micro pattern (over $1.5{\mu}m$) exposure. The other was for semiconductor applications which require small areas (1.5") and nano pattern (under $0.2{\mu}m$) exposure. However, holographic lithography can print fine patterns from $0.35{\mu}m$ to $1.5{\mu}m$ keeping the exposure area inside 6". This is one of the great advantages in order to realize high speed fine pattern photolithography. How? It is because holographic lithography is taking holographic optics instead of projection optics. A hologram mask is the key component of holographic optics, which can perform the same function as projection optics. In this paper, Surface-Relief TIR Hologram Mask technology is introduced, and enables more robust hologram masks than those previously reported that were formed in photopolymer recording materials. We describe the important parameters in the fabrication process and their optimization, and we evaluate the patterns printed from the surface-relief TIR hologram masks.

• Korean Journal of Medicinal Crop Science
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• v.15 no.5
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• pp.339-345
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• 2007

Field performance and morphological characterization was conducted on seven transgenic lines of Codonopsis lanceolata expressing ${\gamma}-TMT$ gene. The shoots were obtained from leaf explants after co-cultivation with Agrobacterium tume-faciens strain LBA 4404 harboring a binary vector pYBI 121 that carried genes encoding ${\gamma}-Tocopherol$ methyltransferase gene (${\gamma}-TMT$) and a neomycin phosphotransferase II gene (npt II) for kanamycin resistance. The transgenic plants were transferred to a green house for acclimation. Integration of T-DNA into the $T_0\;and\;T_1$ generation of transgenic Codonopsis lanceolata genome was confirmed by the polymerase chain reaction and southern blot analysis. The progenies of transgenic plants showed phenotypic differences within the different lines and with relative to control plants. When grown in field, the transgenic plants in general exhibited increased fertility, significant improvement in the shoot weight, root weight, shoot height and rachis length with relation to the control plants. However, all seven independently derived transgenic lines produced normal flower with respect to its shape, size, color and seeds number at its maturity. Indicating that the addition of a selectable marker gene in the plant genome does not effect on seed germination and agronomic performance of transgenic Codonopsis lanceolata. $T_1$ progenies of these plants were obtained and evaluated together with control plant in a field experiment. Overall, the agronomic performance of $T_1$ progenies of transgenic Codonopsis lanceolata showed superior to that of the seed derived non-transgenic plant. In this study, we report on the morphological variation and agronomic performance of transgenic Codonopsis lanceolata developed by Agrobacterium transformation.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.1
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• pp.120-130
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• 2009

This study focuses on the methodology of an ecological interpretation of Korean traditional landscapes through both life-oriented philosophy and traditional Korean philosophy which are similar to ecology. Also, useful tools for discovering an ecological technique of formation based on the ecological thoughts in ancestors' life are shown. Ecological key words as interpretative tools on the traditional landscape replaced ecological concepts in Korean culture and landscape. There are 'Bonsung(本性; the original nature)', 'Chungjeol(中絶; moderation)', 'Hyoyul(效率; efficiency)', 'Sangsaeng(相生; symbiosis)', 'Jasaeng(自生; self-generation)', 'Chunghwa(中和; neutralization)', 'Bangtong(旁通; communication)', and 'Byuntong(變通; variableness)'. For the case study, the concepts of 'spatial structure', 'constructive elements in the traditional gardens', and 'structural elements in the dwelling houses' were extracted from $\ulcorner$Imwonkyeongjeji$\lrcorner$ as an interpretative subject. As a result, Jeongon house, Jongtaek of Choi's family(the first incoming resident) showed us an ecological technique of formation by interpretation on the composing elements. Namely, they are natural dwelling houses in harmony with natural conditions and delicate relational styles. Five kinds of ecological characteristics were exposed. They are: 1. land use method following natural features('本性' '相生' '中和'), 2. physical and spatial elements in a body with nature('中絶' '相生' '中和'), 3. sustainable circulation system by recycling limited resources('效率' '自生' '旁通'), 4. use of natural materials based on the regional climate ('中絶' '效率' '自生') and 5. plane and structural decision by microclimate('效率' '自生' '變通'). Consequently, the dwelling houses and their traditional gardens aimed at the consuming space of the efficient resources by utilizing and circulating natural energy more than different types of the traditional spaces.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.1
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• pp.47-58
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• 2018

The heterogeneous cellular network (HCN) is most significant as a key technology for future fifth generation (5G) wireless networks. The heterogeneous network considered consists of randomly macrocell base stations (MBSs) overlaid with femtocell base stations (BSs). The stochastic geometry has been shown to be a very powerful tool to model, analyze, and design networks with random topologies such as wireless ad hoc, sensor networks, and multi- tier cellular networks. The HCNs can be energy-efficiently designed by deploying various BSs belonging to different networks, which has drawn significant attention to one of the technologies for future 5G wireless networks. In this paper, we propose switching off/on systems enabling the BSs in the cellular networks to efficiently consume the power by introducing active/sleep modes, which is able to reduce the interference and power consumption in the MBSs and FBSs on an individual basis as well as improve the energy efficiency of the cellular networks. We formulate the minimization of the power onsumption for the MBSs and FBSs as well as an optimization problem to maximize the energy efficiency subject to throughput outage constraints, which can be solved the Karush Kuhn Tucker (KKT) conditions according to the femto tier BS density. We also formulate and compare the coverage probability and the energy efficiency in HCNs scenarios with and without coordinated multi-point (CoMP) to avoid coverage holes.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.279-288
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• 2014

Nuclear energy is expected to meet the growing energy demand while avoiding CO2 emission. However, the problem of accumulating spent fuel from current nuclear power plants which is mainly composed of uranium oxides should be addressed. One of the most practical solutions is to reduce the spent oxide fuel and recycle it. Next-generation fuel cycles demand innovative features such as a reduction of the environmental load, improved safety, efficient recycling of resources, and feasible economics. Pyroprocessing based on molten salt electrolysis is one of the key technologies for reducing the amount of spent nuclear fuel and destroying toxic waste products, such as the long-life fission products. The oxide reduction process based on the electrochemical reduction in a LiCl-$Li_2O$ electrolyte has been developed for the volume reduction of PWR (Pressurized Water Reactor) spent fuels and for providing metal feeds for the electrorefining process. To speed up the electrochemical reduction process, the influences of the feed form for the cathode and the type of anode shroud on the reduction rate were investigated.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.24-34
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• 2015

As recent multilateral collaboration design system has been advanced, BIM based data exchange is a key factor for successful next generation building project. Even though many studies have been trying to set up a data compatibility system for collaboration, There are still a lot of problem in data exchange between design and engineering phase. Therefore, In this study, we analysis causes of problem for information exchange and suggest a IFC based Information exchange framework for improving BIM based design collaboration environment. In order to find out problems that hinder establishment of advanced open BIM information exchange, proper analysis about transition of process from current and to-be BIM based design collaboration process is important, at first. From analysis of main obstacles to information exchange, this research suggests solution plan using open API and IFC based BIM collaboration supporting system. The suggested open API solution named Integrity feedback system perform a role making up for weak point derived from IFC based data exchange. And main system suggestion about framework for IFC based information exchange reflect technological system support, requirement of function for collaboration including API/BCF plug-in.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.4 no.1
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• pp.1-27
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• 2009

The bio-technology industry is a technology-intensive high value added area where R&D and securing core technology are important. Many countries across the world are nationally supporting and nurturing this industry as a next generation growth engine. This study aims to introduce development plan for the bio-tech industry in Korea through analyzing factors for the development of bio-tech industry by using Analytic Hierarchy Process (AHP) and to set the priorities among such factors. The analysis shows that key element for the development of bio-tech industry is technological capacity in the present and in the year of 2015. It also shows that it is essential to have government support and investment in strengthening R&D and cooperative system of industry, academia and research institute for the development of basic original technology. In addition, it suggested 5 plans for the development of bio-tech industry in Korea including securing new technologies in bio-tech industry, improving efficiency of R&D management system, protecting and culturing traditional bio-tech industry, creating emerging markets and efficiently providing support to nurture bio-venture companies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.10
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• pp.1267-1274
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• 2012

A guide vane plays a key role in controlling the flow rate of water supplied to the turbine of a hydropower plant. It has been reported that guide vane bearing bushings are subjected to considerable wear, which requires them to be maintained. An ancillary service such as frequency control and black start causes cyclic low opening operation of the guide vanes. It is empirically well known that such operation increases the wear rate of the guide vane bearing bushing. In this study, the effect of low opening operation on the increasing wear of the guide vane bearing bushing is quantitatively assessed via finite element flow analysis, finite element stress analysis, and relative wear evaluation. As a result of the assessment, it is identified that the pressure applied on the guide vane surface increases and the contact length between the outer surface of the guide vane stem and the inner surface of the bearing bushing decreases with a decrease in the opening of the guide vane. In addition, low opening of the guide vanes results in an increase in the relative wear owing to the generation of high contact pressure on the bearing bushing surfaces.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.3-6
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• 2001

Inflammation is an outcome or an end effect of disruption of complex immunological balance. A variety of approaches to control immunological unbalance have been tried, and some of them are in practice in the clinic. Since inflammatory disorders are reflection of very complex immunological responses, it should be difficult to have such disorders under complete control. Thus, most of the drugs, being marketed and under development, possess some degrees of undesired side offsets originating from disruption of immunological balance. Steroids are excellent drugs suppressing inflammation in short term, however, long-term use of steroids would incur a serious side effect of "rebound". Another example is TNF-${\alpha}$-neutralizing agents, such as enbrel and infliximab. TNF-${\alpha}$ has been known to play a key role in the exacerbation of inflammation, and knock-out of TNF-${\alpha}$ is regarded essential to control of chronic inflammation. The TNF-${\alpha}$-neutralizing drugs in the market are regarded very efficient in the management of rheumatoid arthritis. Upon long term use, however, those drugs cause sepsis to a certain proportion of patients. It is ironical that a high plasma level of TNF-${\alpha}$ is known to be responsible for sepsis, and that the drugs scavenging TNF-${\alpha}$ cause sepsis. The above two examples illustrate well the difficulty of discovering an anti-inflammatory drug without unwanted immunological side effects. An anti-inflammatory drug would make a case in the market, as long as the drug has huge therapeutic benefits compared to its expected but unwanted immunological side effects, where cyclooxygenase-2 inhibitors are positioning. In this presentation, will be discussed general aspects of cyclooxygenase-2 inhibition in conjunction with 3(2Η)furanone derivatives, a novel class of COX-2 inhibitors.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.4
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• pp.383-399
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• 2020

Optimizing the spacing of the disc cutter is a key element in the design of the TBM cutter head, which determines the drilling performance of the TBM. The full-scale linear cutting test is known as the most reliable and accurate test for calculating the spacing of the disc cutter, but it has the disadvantage of costly and time-consuming for the full-scale experiment. In this study, through the numerical analysis study based on the discrete element method, the tendency between Specific Energy-S/P ratio according to uniaxial compression strength and penetration depth of rock was analyzed, and the optimum spacing of 17-inch disc cutter was derived. To examine the appropriateness of the numerical analysis model, the rolling force acting on the disc cutter was compared and reviewed with the CSM model. As a result of numerical analysis for the linear cutting test, the rolling force acting on the disc cutter was analyzed to be similar to the rolling force derived from the theoretical formula of the CSM model. From the numerical analysis on 5 UCS cases (50 MPa, 70 MPa, 100 MPa, 150 MPa, 200 MPa), it is found that the range of the optimum spacing of the disc cutter decreases as the rock strength increases. And it can be concluded that 80~100 mm of disc cutter spacing is the optimum range having minimum specific energy regardless of rock strength. This tends to coincide with the optimal spacing of previously reported disk cutters, which underpins the disk cutter spacing calculated through this study.