• Journal of Biosystems Engineering
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• v.7 no.1
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• pp.53-61
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• 1982

As an attempt to reduce the consumption of petroleum resources and to improve the performance of a kerosene engine, a series of experiments was conducted using several kinds of ethanol-kerosene blends under the various compression ratios. The engine used in this study was a single-cylinder, four-cycle kerosene engine having a compression ratio of 4.5. To investigate the feasibility of ethanol-kerosene blends in the original engine, kerosene and blends of 5-percent, 10-percent, and 20-percent-ethanol, by volume, with kerosene were used. And to investigate the feasibility of improving the performance of the kerosene engine, a portion of the cylinder head was cut off to increase the compression ratio up to 5.0 by reducing the combustion chamber volume. Kerosene and blends of 30-percent and 40-percent-ethanol, by volume, with kerosene were used for the modified engine with an increased compression ratio. Variable speed tests at wide-open throttle were also conducted at five speed levels in the range of 1000 to 2200 rpm for each compression ratio and fuel type. Volumetric efficiency, engine torque, and brake specific fuel consumption were determined, and brake thermal efficiency based on the lower heating values of kerosene and ethanol was calculated. The results obtained in the study are summarized as follows: A. Test with the original engine: (1) No abnormal conditions were found when burning ethanol-kerosene blends in the original engine. (2) Volumetric efficiency increased with ethanol concentration in blends. When burning blends of 5-percent, 10-percent, and 20-percent ethanol, by volume, with kerosene, average volumetric efficiency increased 1.6 percent, 2.6 percent, and 4.1 percent respectively, than when burning kerosene. (3) Mean engine torque increased 5.2 percent for 5-percent-ethanol blend, 9.3 percent for 10-percent-ethanol blend, and 11.5 percent for 20-percent-ethanol blend than for kerosene. Increase in engine torque when using ethanol-kerosene blends was due to the improved combustion characteristics of ethanol as well as an increase in volumetric efficiency. (4) Up to ethanol concentration of 20 percent, mean brake specific fuel consumption was nearly constant inspite of the difference in heating value between ethanol and kerosene. (5) Brake thermal efficiency increased 0.3 percent for 5-percent-ethanol blend, 3.8 percent for 10-percent-ethanol blend, and 6.8 percent for 20-percent-ethanol blend than for kerosene. B. Test with the modified engine with an increased compression ratio: (1) When burning kerosene, mean volumetric efficiency, engine torque, and brake thermal efficiency were somewhat lower than for the original engine. (2) Engine torque increased 15.1 percent for 30-percent-ethanol blend and 18.4 percent for 40-percent-ethanol blend than for kerosene. (3) There was no significant difference in brake specific fuel consumption regardless of ethanol concentration in blends. (4) Brake thermal efficiency increased 15.0 percent for 30-percent-ethanol blend and 19. 5 percent for 40-percent-ethanol blend than for kerosene.

• Journal of Science of Art and Design
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• v.11
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• pp.79-108
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• 2007

"Printing is an Art of reproduction & a Technique of However printing has extended its limitation from a genre of reproduction itself and now it stands on the turning point as an art such as painting or sculpture which expresses artist's originality. Early Printing has had relations in depth with press printing in terms of information recording, preservation, and transmission. It was acknowledged value in a way of information satisfaction different from how it is valued as a pure art today. But, later printing has transferred its function from a mean of reproduction to pure art due to the development of printing skills and photography invention. It can be said that the concept of modern printing is taking over its genealogy as a creative work not as just printing. Also its expression capability is widen to dimensional printing and high-tech multimedia from original tradition techniques. As we discussed above, modern painting is very open to various changes. This modern painting aspect can be seen as an extended interpretation of 'board' concept. This dissertation raises a question why monotype and monoprint couldn't secure its position in printing history in spite of numerous artists' tryouts in its way. Monotype and monoprint fundamentally based on intaglio technique in its history. Yet, its systematic study hasn't been worked out. This is because of the lack of recognition of monotype and monoprint's originality as printing. Especially in monoprint, it has known as an early stage in copperplate printing process which is an attempt to solve the technique limitation or trial work for edition. Likewise the reason why monotype and monoprint remains at the edge of printing border ambiguously is because of conceptual, technical characteristics which are against traditional printing. In traditional printing, the concept of board is important as a method of reproduction. Different from the fact, monotype and monoprint accept the form of medium 'board' conceptually out of limited condition as mentioned. Thus monotype and monoprint hasn't stand out for several reasons until late 20th century when it started come out to public as people starts to have interests that works from famous artists are actually based on monotype and monoprint. This dissertation likes to step into the monotype and monoprint theoretically which is not well known in domestic and try to study the meaning of monotype and monoprint as a printing medium which is also hasn't been considered sincerely. For this study the process follow as below. First, look into how monotype and monoprint has a concept and history. Next, check differences through comparison with traditional printing and how printing can be understood in what aspects at the same time. After, verify how monotype and monoprint have influence on the acceptance of extended concept of 'board'. This study will show the expressional possibility of monotype and monoprint which has already known as 'tableau printing' in today's situation where adventurous experiments of printing medium are going on with the development of technology.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.441-451
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• 2013

Samples for estimating concentrations of polycyclic aromatic hydrocargons(PAHs), total petroleum hydrocarbons(TPHs), and benzene-toluene-ethylbenzene-xylene(BTEX) were collected at the tidal flat sediments of 8 coastal sites in Incheon, at seventy-two sampling stations for the surface sediment and twenty-four stations for the sediment core, twice in the spring and fall in 2011. This study was performed to evaluate the distributions of seasonal and spatial concentrations of PAHs, TPHs, and BTEX in the tidal flat sediments. The source origin of PAHs were carried out. The total average concentration of PAHs in the tidal flat sediment was $95.62{\mu}g/kg$. The characteristic of PAHs concentration distributions was observed that the average concentration in the autumn was lower than that in the spring, and higher concentration in the sediment core than the surface sediment, and greater vertical concentration at the top rather than the bottom in the sediment core. The total average concentration of TPHs at all sampling sites was in the value of 46 mg/kg. The characteristic of the TPHs concentration distribution was observed that the average concentration in the fall was much higher than that in the spring, and higher concentration in the surface sediment than the sediment core. The possible source of PAHs inputs were mainly derived from both pyrogenic and petrogenic origin at the surface sediment at Janghwari site and the sediment cores of both Sorae and Okyeon sites, while the rest sites of study areas originated with pyrogenic combustion.

• Korean Journal of Materials Research
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• v.21 no.5
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• pp.255-262
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• 2011

This paper has relatively high technical standard and experimental skill. The fabrication of TCO film with high transparency, low resistance and low chromaticity require exact control of several competing factors. This paper has resolved these problems reasonably well, thus recommended for publication. Indium tin oxide(ITO) thin films were by D.C. magnetron roll-to-roll sputter system utilizing ITO and $SiO_2$ targets of ITO and $SiO_2$. In this experiment, the effect of D.C. power, winding speed, and oxygen flow rate on electrical and optical properties of ITO thin films were investigated from the view point of sheet resistance, transmittance, and chromaticity($b^*$). The deposition of $SiO_2$ was performed with RF power of 400W, Ar gas of 50 sccm and the deposition of ITO, DC power of 600W, Ar gas of 50 sccm, $O^2$ gas of 0.2 sccm, and winding speed of 0.56m/min. High quality ITO thin films without $SiO_2$ layer had chromaticity of 2.87, sheet resistivity of 400 ohm/square, and transmittance of 88% and $SiO_2$-doped ITO Thin film with chromaticity of 2.01, sheet resistivity of 709 ohm/square, and transmittance of more than 90% were obtained. As a result, $SiO_2$ was coated on PET before deposition of ITO, their chromaticity($b^*$) and transmittance were better than previous results of ITO films. These results show that coating of $SiO_2$ induced arising chromaticity($b^*$) and transmittance. If the thickness of $SiO_2$ is controlled, sheet resistance value of ITO film will be expected to be better for touch screen. A four point probe and spectrophotometer are used to investigate the properties of ITO thin films.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.13-18
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• 1978

The present study was conducted to elucidate the pattern in changes of trimethylamine oxide and related compounds in the muscle of Alaska pollack during drying, especially referred to formaladehyde and dimethylamine. Three kinds of dried samples of Alaska pollack, sun dried, hot-air dried, and salted-sun dried, were prepared and analyzed for their contents of trimethylamine oxide, trimethylamine, dimethylamine, and formaldehyde. The amount of trimethylamine oxide remained in the salted-sun dried sample was relatively higher than those in the other two samples. In the content of trimethylamine, the hot-air dried sample showed an exceedingly high value shelving forty-two times higher than the raw sample while the other two samples showed barely three to four times content based on the raw sample. The dimethylamine content in the hot-air fried sample was comparatively lower than those in the other two samples, the former marked about ten folds of the raw sample's and tile latter showed about fifteen folds, respectively. Refering to the content of formaldehyde, it decreased to eighty-three percent of initial content in the hot-air dried sample. On the contrary, it increased about two times initial content in the other two samples, respectively. As a tendency, the formaldehyde content appeared increased or decreased correlatively with the dimethylamine content, whereas the case was reverse for the trimethylamine content.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.525-529
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• 2016

Biomass co-firing to existing thermal power plants is one of the most economical and efficient way to reduce $CO_2$ emission from the plant. There are several methods of co-firing and it can be categorized into (1) Parallel co-firing, (2) Indirect co-firing, and (3) Direct co-firing. Parallel co-firing is the most expensive way to high-ratio co-firing because it requires biomass dedicated boiler. Direct co-firing is widely used because it does not need high capital cost compared with the other two methods. Regarding the direct co-firing, it can be classified into three methods- Method 1 does not need retrofit of the facilities because it uses existing coal mills for pulverizing biomass fuels. In this case high-ratio co-firing cannot be achieved because of poor grindability of biomass fuels. Method 2 needs biomass-dedicated mills and revision of fuel streams for the combustion system, and Method 3 needs additional retrofit of the boiler as well as biomass mills. It can achieve highest share of the biomass co-firing compared with other two methods. In Korea, many coal power plants have been adopting Method 1 for coping with RPS(Renewable portfolio standards). Higher co-firing ratio (> 5% thermal share) has not been considered in Korean power plants due to policy of limitation in biomass co-firing for securing REC(Renewable Energy Certificate). On the other hand, higher-share co-firing of biomass is widely used in Europe and US using biomass dedicated mills, following their policy to enhance utilization of renewable energy in those countries. Technical problems which can be caused by increasing share of the biomass in coal power plants are summarized and discussed in this report. $CO_2$ abatement will become more and more critical issues for coal power plants since Paris agreement(2015) and demand of higher share of biomass in the coal power plants will be rapidly increased in Korea as well. Torrefaction of the biomass can be one of the best options because torrefied biomass has higher heating value and grindability than other biomass fuels. Perspective of the biomass torrefaction for co-firing is discussed, and economic feasibility of biomass torrefaction will be crucial for implementation of this technology.

• Journal of Korean Neurosurgical Society
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• v.61 no.3
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• pp.363-375
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• 2018

Intraoperative monitoring (IOM) utilizes electrophysiological techniques as a surrogate test and evaluation of nervous function while a patient is under general anesthesia. They are increasingly used for procedures, both surgical and endovascular, to avoid injury during an operation, examine neurological tissue to guide the surgery, or to test electrophysiological function to allow for more complete resection or corrections. The application of IOM during pediatric brain tumor resections encompasses a unique set of technical issues. First, obtaining stable and reliable responses in children of different ages requires detailed understanding of normal age-adjusted brain-spine development. Neurophysiology, anatomy, and anthropometry of children are different from those of adults. Second, monitoring of the brain may include risk to eloquent functions and cranial nerve functions that are difficult with the usual neurophysiological techniques. Third, interpretation of signal change requires unique sets of normative values specific for children of that age. Fourth, tumor resection involves multiple considerations including defining tumor type, size, location, pathophysiology that might require maximal removal of lesion or minimal intervention. IOM techniques can be divided into monitoring and mapping. Mapping involves identification of specific neural structures to avoid or minimize injury. Monitoring is continuous acquisition of neural signals to determine the integrity of the full longitudinal path of the neural system of interest. Motor evoked potentials and somatosensory evoked potentials are representative methodologies for monitoring. Free-running electromyography is also used to monitor irritation or damage to the motor nerves in the lower motor neuron level : cranial nerves, roots, and peripheral nerves. For the surgery of infratentorial tumors, in addition to free-running electromyography of the bulbar muscles, brainstem auditory evoked potentials or corticobulbar motor evoked potentials could be combined to prevent injury of the cranial nerves or nucleus. IOM for cerebral tumors can adopt direct cortical stimulation or direct subcortical stimulation to map the corticospinal pathways in the vicinity of lesion. IOM is a diagnostic as well as interventional tool for neurosurgery. To prove clinical evidence of it is not simple. Randomized controlled prospective studies may not be possible due to ethical reasons. However, prospective longitudinal studies confirming prognostic value of IOM are available. Furthermore, oncological outcome has also been shown to be superior in some brain tumors, with IOM. New methodologies of IOM are being developed and clinically applied. This review establishes a composite view of techniques used today, noting differences between adult and pediatric monitoring.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.8
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• pp.664-669
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• 2012

Nano-structured one-dimensional $Na_2Ti_6O_{13}$ particles were synthesized by a molten salt process. Effects of processing parameters on the microstructure and band gap energy of the $Na_2Ti_6O_{13}$ powder were studied in this paper. For the synthesis of the $Na_2Ti_6O_{13}$ particles, two different raw materials of tubular shaped Na-titanate (Na-TiNT) and spherical shaped $TiO_2$ were utilized. Synthesizing with the raw material of Na-TiNT, around 70nm thick 1D-$Na_2Ti_6O_{13}$ with the bandgap energy of 3.5 eV was obtained at $810^{\circ}C$. Below $810^{\circ}C$ or without the presence of NaCl, 1D-$Na_2Ti_6O_{13}$ was in a relatively short in length and agglomerated state. With the processing temperature increased, the thickness of the 1D-$Na_2Ti_6O_{13}$ was also observed to be increased. On the other hand, when $TiO_2$ was employed as a raw material, the mixed amount of $Na_2CO_3$ played an important role in transforming the morphology and phase of the raw material, affecting the bandgap energy of the synthesized product. Specific surface area of the synthesized 1D-$Na_2Ti_6O_{13}$ was significantly affected by the raw and mixed materials as well as processing temperature. When Na-TiNT was processed at $810^{\circ}C$ with NaCl, the specific surface area of the 1D-$Na_2Ti_6O_{13}$ showed the best value of 30.63 $m^2/g$.

• The Transactions of the Korea Information Processing Society
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• v.3 no.1
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• pp.127-143
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• 1996

Advanced countries are very active in deploying the National Information I infrastructure which provides universal service to promise fruitful quality of futuree life. Even in the distributed environment, we can closely converse, work together, and share information in a very convenient way. This is actually enabled with the help of groupware technology, which are currently focused and researched in a larger popularity. The aim of this study is to design a portable pack for group communications management to support the development of groupware application. In the paper we begin with technical survey, continue to build our own model for group communications man agement, and design its architecture and procedure. We also suggest group addressing mechanism under Internet environment such as how to create IP multicast address and IP port number dynamically and as a globally unique value for the communication session, with the help of the hierarchical and distributed address managers. We also indicate the reliable data transmission services to remedy the unreliable feature of the UDP multicast services, and finally the architecture/ applied to support the practical applications is briefly discussed for verification of the designed concept.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.4
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• pp.139-148
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• 2016

The importance of technology commercialization is being emphasized more and more, but high technology excellence does not always lead to a successful business. In addition, companies that invest heavily in basic research and technology development are also not always able to guarantee high profits. This is due to the technical problems when present in step research and development levels are difficult to commercialize. And the market will not work rationally is also the cause of the problem. Therefore, to effectively utilize the resources necessary to ensure such partners to build alliances and cooperation with external funding or manpower is crucial to commercialize the research results of basic science successfully. In previous studies, it has been made many studies in accordance with the approach to the technology (e.g. Research and Development, Management of Technology, Technology Innovation, etc.). But the study of technology commercialization point of view is not being done much. This study should explores the available business required, or realized in the process of researching the basic science and trying to understand the imperfections of the market through the property of technology (tacit knowledge, objectified value of technology and the information asymmetry between innovation subjects, etc.). In addition, this paper, we try to focus on a strategic approach to the role of International Science Business Belt (ISBB) with success in science and technology business as appropriate countermeasures about breaking the 'Valley of Death.