• Journal of Life Science
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• v.22 no.5
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• pp.650-656
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• 2012

To reduce the production cost of $Pleurotus$ $ostreatus$, discarded medicinal sludge was collected from oriental medical clinics to develop the $Pleurotus$ $ostreatus$ culture medium. According to the analysis of the proximate composition of the materials used in Korean herb medicine, the crude ash contents of $Carthamus$ $tinctrius$ L stem and $Acanthopanax$ $chiisanensis$ were 11.6% and 10.1% respectively, which were relatively higher than the 9.6% of the control medium, waste cotton. Crude protein was detected in 9.8% of the waste cotton medium, whereas it was detected in 14.9%, 13.9%, 13.4%, and 11.5%, of wild mugwort, $Acanthopanax$ $\underline{chiisanensis}$, medicinal sludge, and $Carthamus$ $tinctrius$ L stem, respectively, which are all higher than the control. The pH of medicinal sludges, wild mugwort, and $Aacanthopanax$ $chiisanenses$ ranged from 5.27 to 5.72, which was similar to the 5.70 pH value of waste cotton. In the case of addition concentration of each Korean herb medicine material influencing mycelial growth of the $Pleurotus$ $ostreatus$, the 9% concentration was more favorable compared to that of 3% and 6%. However, the addition of Korean herb medicine materials did not significantly affect the growth of $P.$ $tolaassi$ and $Trichoderma$ $sp.$ According to a field experiment that added 9% of medicinal sludge into the waste cotton medium, the mycelial growth of mushrooms was facilitated by approximately 2 days, and the mushroom yield was increased by 10~15%. Furthermore, pileus and stipe of the mushrooms were even and superior in quality.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.5
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• pp.17-23
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• 2017

Optical current sensors are suitable for operation in high voltage and high current environments such as power plants due to they are not affected by electromagnetic interference and have excellent insulation characteristics. However, as they operate in a harsh environment such as large temperature fluctuation and mechanical vibration, high reliability of the sensor is required. Therefore, many groups have been working on enhancing the reliability. In this work, an integrated optical current sensor incorporating polarization-rotated reflection interferometer is proposed. By integrating various optical components on a single chip, the sensor exhibits enhanced stability as well as the solution for low-cost optical sensors. Using this, we performed the characterization for the actual field application. By using a large power source, the current of 0.3 kA~36 kA was applied to the photosensor and the linear operation characteristics were observed. The error of the sensor was within $0{\pm}.5%$. Even when operating for a long time, the error range of the sensor was kept within $0{\pm}.5%$. In addition, the measurement of the frequency response over the range of 60 Hz to 10 kHz has confirmed that the 3-dB frequency band of the proposed OCT is well over 10 kHz.

• Journal of Digital Contents Society
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• v.10 no.4
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• pp.639-648
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• 2009

Earth's environment issues are introduced recently and every year the social loss have been occurred by the impact of various disaster. This kind of disaster and weather problems are the increasing reason of electricity transmission network equipment's failures because of exposing by the natural environment. The emergency and abnormal status of electricity equipment make the power outage of manufacturing plant and discomfort of people's lives. So, to protect the electricity equipment from the natural disasters and to supply the power to customer as stable, the supporting systems are required. In this paper, the research results are described the development process and the outcomes of the real-time natural disaster failure analysis information system including the describing about the impact of disaster and weather change, making the natural weather information, and linking the realtime monitoring system. As of development process, according to application development methodology, techniques are enumerated including the real time interface with related systems, the analysing the geographic information on the digital map using GIS application technology to extract the malfunction equipment potentially and to manage the equipments efficiently. Through this system makes remarkable performance it minimize the failures of the equipments, the increasing the efficiency of the equipment operation, the support of scientific information related on the mid-term enhancement plan, the savings on equipment investment, the quality upgrading of electricity supply, and the various supports in the field.

• Elastomers and Composites
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• v.52 no.2
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• pp.114-130
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• 2017

Enhancing the properties of rubber, such as the tensile strength, modulus, and wear abrasion, by the addition of carbon black and silica as fillers is very important for improving the performance of rubber products. In this review, we summarize the general features of 'the reinforcement of rubber by fillers' and the equations for representing the reinforcement phenomena. The rubber reinforcement was attributed to enhancement of the following: the rubber, bound rubber, formation of networks, and combination between rubber chains and silica followed by entanglement. The reinforcement capability of silica species with different surface and networked states demonstrated the importance of the connection between the silica particles and the rubber chains in achieving high reinforcement. The model involving combination followed by entanglement can provide a plausible explanation of the reinforcement of rubber by carbon black and silica because the combination facilitates the concentration of rubber chains near the filler particles, and entanglement of the rubber chains around the filler particles enforces the resistance against deformation and breakage of rubber compounds, resulting in high reinforcement.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.174-183
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• 2004

The knowledge of rock strength is important in assessing wellbore stability problems, effective sanding, and the estimation of in situ stress field. Numerous empirical equations that relate unconfined compressive strength of sedimentary rocks (sandstone, shale, and limestone, and dolomite) to physical properties (such as velocity, elastic modulus, and porosity) are collected and reviewed. These equations can be used to estimate rock strength from parameters measurable with geophysical well logs. Their ability to fit laboratory-measured strength and physical property data that were compiled from the literature is reviewed. While some equations work reasonably well (for example, some strength-porosity relationships for sandstone and shale), rock strength variations with individual physical property measurements scatter considerably, indicating that most of the empirical equations are not sufficiently generic to fit all the data published on rock strength and physical properties. This emphasizes the importance of local calibration before one utilizes any of the empirical relationships presented. Nonetheless, some reasonable correlations can be found between geophysical properties and rock strength that can be useful for applications related to wellhole stability where haying a lower bound estimate of in situ rock strength is especially useful.

• Ecology and Resilient Infrastructure
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• v.7 no.1
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• pp.63-71
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• 2020

Various types of amendments have been studied for heavy metal stabilization in soil. However, researches on the effect of amendments on alkali soil and their effects on the plants at various edible parts are insufficient. The aim of this study was to evaluate the stabilization efficiency of heavy metals and their transfer into edible parts of food crops. Abandoned mine area was selected and 3 types of amendments (lime stone, LS; steel slag, SS; acid mine drainage sludge, AMDS) was applied with 3% (w/w). in field. After 6 month aging, Chinese cabbage (leafy), bok choy (leafy), garlic (root) and red pepper (fruit) were transplanted and cultivated. For chemical assessment, total concentration and bioavailability using Mehlich-3 solution were determined. For biological assessment, fresh weight and heavy metal uptakes were analyzed. It was revealed that AMDS reduced bioavailability most effectively, resulting in the decrease in heavy metal concentration in edible parts of all crops. When explaining the heavy metal uptake of plants, the bioavailability was more appropriate than the total contents of soil heavy metals. Therefore, bioavailability-based further research and management practices should be carried out continuously for the sustainable environment management, safe crop production, and human health risk reduction.

• Journal of Science and Technology Studies
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• v.4 no.1 s.7
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• pp.1-30
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• 2004

In this paper, I have attempted to show how the environmental controversy surrounding the Saemangeurn Reclamation Project in Korea has been framed as narrow scientific debates. First of all, science, or specifically the Expert Review Pane, has played dual roles in the controversy. On the one hand, it has contributed to illuminating the future environmental impacts of reclamation, by so doing, to providing a momentum to reconsider the project. This has significant meaning that environmental concerns successfully checked the symbolic national project of developmental era through adopting a joint-investigation scheme that guaranteed participation of environmental groups on an equal footing with the government. On the other hand, by limiting the scope and participants of discussion, it fundamentally blocked the possibilities of public debates and deliberative decision-making with full considerations of the political, social, and cultural aspects of the controversy. I have shown that this is due to the realist belief shared by both the developers and the environmentalists in Korea that 'proper' science would disclose the truth. Environmental groups, in particular, were naive in evaluating the role of scientific expertise in the controversy and neglected the political role of the Expert Review Pane as a ritual. In opposition to the realist argument, I have shown through the analysis of the water quality debates concerning the future fresh water lakes that scientific 'facts' were not discovered but constructed through complex negotiations, conflicts, and compromises among related actors. The framing of the controversy as an experts' debate has resulted in the exclusion of an important actor from the discussion. Little attention has been paid throughout the controversy to the very people who have lived in the Saemangeum area for generations and will lose their livelihood all together soon. About 20,000 fishermen are living on the Saemangeum tidal flats.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.254-262
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• 2003

In this study, the results of applying cold weather concreting mixed with Accelerator for Freeze Protection(AFP) to full scale structures are presented. Since the determination of W/C and amount of AFP significantly have an effect on strength gain and protection of frost damage in early, a full investigation is needed to determine these values at stage of nux design. The flowability of fresh cold weather concreting with AFP was similar to the same W/C. Lower loss of workability and initial slump flow of concrete using superplasticizer of polycarboxylic ester than that of melamine sulphonate showed that polycarboxylic ester was more effective on elapsed time. Temperature histories of specimens located in insulation boxes at the site was similar to that of structures. Thus, it is cleared that simple adiabatic curing method is effective for evaluating in-place concrete strength than specimens cured by sealing method. The investigation results of development of compressive strength of cold weather concreting included AFP with curing methods by logistic curves indicated that AFP can be effective to gain strength at lower temperature than normal curing temperature. In field testing, vinyl sheets were placed over the concrete sections and AFP enabled concrete to gain $5N/{mm}^2$ to protect frost damage in early ages and specified compressive strength of concrete at 28 days under average temperature of $-2^{\circ}C$ (lowest temperature was $-12^{\circ}C$) during site application.

• Korean journal of communication and information
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• v.60
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• pp.52-74
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• 2012

Legislation needs to be understood within a political, societal relationship among lawmaking bodies rather than by legal provision itself. In order to examine features and functions of communication in the process of legislation, this study conducted focus group interviews with experts as well as in-depth individual interviews. The result of this research as follows: First, the study found that although the domestic legislative process has been made by active interactions among lawmaking subjects, it was hard to conclude that this procedure is providing effective and productive legislative agenda because of chaotic communications made along the process. Second, the study found that national legislative process has been gradually moving, although restricted, to an open political space, the National Assembly, from a closed space, the executive branch. Third, the study found a remarkable feature including growing influence of experts groups and civic organizations in the legislative process. It is a significant change that legislative staff such as National Assembly aides, investigators, expert committeemen and deputy director generals played a role of "insiders," unnoticeably influencing the legislative process, and that civic organizations and NGOs, which have been excluded in the previous legislative processes, emerged as a new influencing circle in the process. Lastly, the study found that media organizations, in the process of developing agenda, had a strong impact on the National Assembly as a subject forming public issues and as a messenger of the legislative agenda while they played a limited role in affecting the government. This study discusses why communication in the domestic legislative process is important and what are some hindering and facilitating factors in the process.

• 대한공업교육학회지
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• v.33 no.2
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• pp.44-71
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• 2008

This paper was intended to investigate employment conditions and career planning of ex-participants of the customized training program(CTP) in Technical High Schools for the specific Small and Medium Business through questionnaires. Results of the research were: 1. The average ex-participant of CTP was employed in small size company with 50 employees, earned 1~1.2 Million Won monthly, worked about 50 hours per week. 2. They were earnestly considering and worried about their career. They had their career goals : Engineer in production and manufacturing, CEO of a company, Design engineer. 3. They were not able to invest enough time and energy in developing their capabilities and skills. 4. There were feelings of respondents, which the main barriers of their career achievement were : (1) their deficiency of personal competencies and endurance. (2) not time enough to learn (3) the fallacy of organizational support and atmosphere.