• Journal of the Korean Society for Precision Engineering
• /
• v.34 no.3
• /
• pp.217-224
• /
• 2017

Structural pipe frames are usually manufactured by complex processes, in which a straight pipe with an arbitrary cross-section is prepared via a roll-forming process and then fabricated into three-dimensional shapes by a secondary process. These conventional processes have low productivity. Recently, the inefficiency of the conventional processes has created the need to develop new forming technologies. In this study, a new incremental roll-forming process is proposed. The study is aimed at verifying the feasibility of the proposed process and investigating the fundamental process parameters using finite-element simulations. The result of the simulation demonstrates that the proposed process can be used effectively for cold fabrication of various shapes of structural pipes. In addition, the result of the investigation of parameters shows that the forming amount, number of roll sets, and distance between roll sets are significant factors to be considered in resolving dimensional errors of the product and improving its quality.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.32-33
• /
• 2009

We propose viewing angle switchable liquid crystal display(LCD) associated with fringe-field switching (FFS) mode with high aperture ratio characteristic. This device is composed of R(red), G(green), B(blue), pixel and W(white) pixel in which R,G,B pixel shows image and white pixel for both viewing angle control and image. Conventional viewing angle controllable liquid crystal display has not transmittance because the liquid crystal only tilts up without rotates in viewing angle control region. In this paper, we suggested that the device has high transmittance characteristic because the LC directors are rotated in which viewing angle control region are generated fringe electric field.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.1
• /
• pp.34-40
• /
• 2009

In fresh water fish hatcheries and farms, Saprolegniales often cause serious mortality to the fish and their eggs. Malachite green is an effective antifungal agent, but is carcinogenic to fish and humans. Alternative antifungal agents are needed. Presently, we tested various concentrations of MBT-01108 (Opuntia ficus-indica extracts) alone and in combination with bronopol, formalin and sodium chloride (MBT-01108 mixture) on in vitro mycelial growth and in vivo remediation of adult eel, Anguilla japonica, infected with Saprolegnia sp. and fertilized eggs of chum salmon, Oncorhynchus keta, to evaluate the compounds' antifungal efficacy on eyed-egg and hatching rates. MBT-Oll08 mixtures incorporating bronopol and formalin at respective concentrations of 50 and 30 parts per million (ppm), and 100 and 20 ppm were most effective in controlling Saprolegnia in vitro and in vivo (P<0.05). Repeated daily exposures to 50 ppm and 100 ppm MBT-01108 were more effective than exposure every 2-3 days post-fertilization for the inhibition of Saprolegnia infection of rainbow trout, Oncorhynchus mykiss eggs as compared with control (0 ppm).

• Journal of Information Technology Applications and Management
• /
• v.21 no.4
• /
• pp.65-96
• /
• 2014

To have global competitiveness in newly growing industry, good quality R&D's in convergence technology arerequired. Korean government also started to emphasize the importance of convergence technology as a new engine of growth for the future development. Since 2008, worldwide energy crisis and concerns on low carbon green growth made people focus on the convergence between information technology (IT) and energy technology (ET). However, the R&D performance comparison among the convergence technologies is not well explored so far. Therefore, this study uses Korea's patent citation database to measure the R&D performance of convergence technologies. We adopt technology development cycle, technology spillover analysis, and technology diffusion analysis to see the knowledge flow from R&D industry to others. We find that IT_ET convergence technology generally shows higher R&D performance than other convergence technologies. Contrary to public belief, convergence R&D by big companies has relatively low performance especially measures in technology spillover and technology diffusion. This implies that they might concentrate on delicate Fuel Cell Energy/Environment Technology (FEIT) or Nano Environment/Energy Information Technology (NEIT) rather than general energy information technologies. We also find that Korea's chemical industry may play a crucial role for the growth of other convergence technologies.

• Journal of Environmental Impact Assessment
• /
• v.17 no.6
• /
• pp.335-348
• /
• 2008

The purpose of this study is to classify the cities on sustainability assessment score studied in advance using cluster analysis, to present efficient management and policy direction based on analysis of sustainability index in 45 cities of all over Gyeongsangnam and Gyeongsangbuk-do. According to the results of cluster analysis, 45 cities were classed into 4 clusters by "livable-welfare city", "environmental -ecological city", "scientific-technological city", and "industrial-economic city". The livable-welfare cities must keep superior environmental sustainability, promote small and medium sized business on regional characteristic. The environmental-ecological cities have to change agriculture into future environmental industry such as ecotourism, bio-industry and landscape agriculture. The scientific-technological cities are going to need support of government scale such as income enlargement of citizen and stable job security. Finally, the industrial-economic cities must increase environmental management plants and improve quality of life through securing green spaces, maintaining public peace and applying UIS because of low quality of environment and life.

• Journal of Plant Biotechnology
• /
• v.42 no.2
• /
• pp.93-103
• /
• 2015

The isolation, cloning, and characterization of an R2R3-MYB transcription factor gene (MtMYB70) from the model legume Medicago truncatula is reported. MtMYB70 consists of a 768-bp coding sequence corresponding to 255 amino acids. Sequence alignment revealed that MtMYB70 cDNA contains conserved R2R3-type MYB domains with highly divergent C terminal regions. MtMYB70 was found to have relatively low sequence homology with known R2R3-MYB genes. Phylogenetic analysis placed the R2R3-MYB domain of MtMYB70 closest to PtMYB1, a known activator of lignin biosynthesis. Overexpression of MtMYB70 under the control of the 35S promoter in transgenic poplar did not cause a significant difference in total lignin content relative to the control, but glucan content was significantly increased in transgenic poplar. Therefore, MtMYB70 might have regulatory role in the biosynthesis of cell wall structural carbohydrates.

• Journal of Soil and Groundwater Environment
• /
• v.23 no.5
• /
• pp.1-16
• /
• 2018

Recent development of lithium ion batteries for vehicles industries have led to a boom in lithium exploration and development for the new generation of batteries. One of the cheapest sources of lithium is the brines hosted in the aquifers of the arid intermontane-closed salar basins. Because the resource is a fluid, with the attendant problems of in-aquifer mixing, reorganization, and lower recovery factors compared with most metalliferous and industrial mineral deposits due to reliance on pumping of the brine from wells for extraction, existing codes for filing resource and reserve estimates require new approach for these prospects. Evaluation of brine resources is complex and requires participation of a variety of qualified experts such as hydrogeologists, geologists, geochemists and chemical engineers. The technical reports disclosing the results of these estimates should reflect the inputs of multi-disciplinary approaches. The requirements for brine resource and reserve evaluation, drawing on several examples from the experiences in the Central Andes are reviewed in this paper.

• Tribology and Lubricants
• /
• v.27 no.3
• /
• pp.125-133
• /
• 2011

The purpose of this study is to develop an engine oil quality monitoring system to warn the abnormal condition of engine oil. To do this, first of all, it is needed a personal controller development to measure the capacitance of a pre-developed engine oil deterioration detection sensor integrated with an oil filter. To measure the capacitance of engine oil in the sensor, it is used the way measuring the electric charging time in a capacitor by impressing DC volt. This method has merits on cost and signal stability. The measured capacitance is compensated by comparing with the one measured by an impedance analyzer. Also, using the dielectric constant gained by an impedance analyzer, the calculating equation of the dielectric constant of engine oil related with the currently developed sensor is decided. Then, the deterioration degree of engine oil is estimated according to the change rate of dielectric constant between green oil and used oil. Finally, using this dielectric constant information together with engine oil temperature and pressure, the currently developed engine oil quality monitoring system is to tell the abnormal state of engine oil.

• Textile Coloration and Finishing
• /
• v.19 no.1 s.92
• /
• pp.53-60
• /
• 2007

In order to optimize the process for development of super deep black fiber, the silica-containing polyester fabric, SN2000, was investigated in terms of mass reduction process by sodium hydroxide, selection of high color strength dyes, and resin treatment. As the results, the mass reduction condition which used 15g/L of sodium hydroxide at $120^{\circ}C$ was determined and Dianix Deep Black Plus was selected for the best deep coloration at around 5% owf. Contrary to the prevailed understanding that the additional use of chromatic dyes would enhance the deep coloration, four kinds of chromatic dyes such as yellow, red, blue, and green dyes did not make great effect on the deep coloration. To increase the effect, the commercial resin that has low refractive index was used additionally and the resin made it possible to lower the lightness of the fabrics down to 8.7 which was generally accepted for super highly deep black fabric.

• Journal of Korean Society of Rural Planning
• /
• v.13 no.2
• /
• pp.51-61
• /
• 2007

The purpose of this paper is to estimate the economic value of Multi-functionality Roles including landscape and so on, which traditional stone fences in Korea possess, using Dichotomous Choice Contingent Valuation Method (DC-CVM). The stone fences is life cultural heritance of regional residents. It has functions like Development of Favorable Landscapes, Maintenance of Cultural Heritage, and Recreation/Relaxation. Expectation from regional visitors shows that the existence and inheritance value of the stone wall is higher then we expected. According to the research that we had done from the people that had agreed to contribute the stone wall. moreover the public commercial value of regional tradition stone was not only 2,900 billion won but also it will increase an economic gain in every year. Therefore, preserving the stone wall that has Multi-functional Roles and values can lead to huge economic value in the future. But farmhouses in the stone wall conservation area are being supported 9 billion won in every year. This is only 0.03% of the income that farmhouse earns per year. Thus, stone wall preservation policy and plan can raise green-tour commercial value of inland area as a long-term inside measurement. Those will have to be propelled continuously.