• Economic and Environmental Geology
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• v.50 no.5
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• pp.341-352
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• 2017

Along with Cs-137 (half-life: 30.17 years), Sr-90 (half-life: 28.8 years) is one of the most important environmental monitoring radioactive elements. Rapid and easy monitoring method for Sr-90 using Laser-Induced Breakdown Spectroscopy (LIBS) has been studied. Strontium belongs to a bivalent alkaline earth metal such as calcium and has similar electron arrangement and size. Due to these similar chemical properties, it can easily enter into the human body through the food chain via water, soil, and crops when leaked into the environment. In addition, it is immersed into the bone at the case of human influx and causes the toxicity for a long time (biological half-life: about 50 years). It is a very reductive and related with the specific reaction that makes wet analysis difficult. In particular, radioactive strontium should be monitored by nuclear power plants but it is very difficult to be analysed from high-cost problems as well as low accuracy of analysis due to complicated analysis procedures, expensive analysis equipment, and a pretreatment process of using massive chemicals. Therefore, we introduce the Laser-Induced Breakdown Spectroscopy (LIBS) analysis method that analyzes the elements in the sample using the inherent spectrum by generating plasma on the sample using pulse energy, and it can be analyzed in a few seconds without preprocessing. A variety of analytical plates for samples were developed to improve the analytical sensitivity by optimizing the laser, wavelength, and time resolution. This can be effectively applied to real-time monitoring of radioactive wastewater discharged from a nuclear power plant, and furthermore, it can be applied as an emergency monitoring means such as possible future accidents at a nuclear power plants.

• Clean Technology
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• v.24 no.2
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• pp.127-134
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• 2018

To reduce the environmental pollution by $NO_x$ from ship engine, International maritime organization (IMO) announced Tier III regulation, which is the emmision regulation of ship's exhaust gas in Emission control area (ECA). Selective catalytic reduction (SCR) process is the most commercial $De-NO_x$ system in order to meet the requirement of Tier III regulation. In generally, commercial ceramic honeycomb SCR catalyst has been installed in SCR reactor inside marine vessel engine. However, the ceramic honeycomb SCR catalyst has some serious issues such as low strength and easy destroution at high velocity of exhaust gas from the marine engine. For these reasons, we design to metallic structured catalyst in order to compensate the defects of the ceramic honeycomb catalyst for applying marine SCR system. Especially, metallic structured catalyst has many advantages such as robustness, compactness, lightness, and high thermal conductivity etc. In this study, in order to support catalyst on metal substrate, coating slurry is prepared by changing binder. we successfully fabricate the metallic structured catalyst with strong adhesion by coating, drying, and calcination process. And we carry out the SCR performance and durability such as sonication and dropping test for the prepared samples. The MFC01 shows above 95% of $NO_x$ conversion and much more robust and more stable compared to the commercial honeycomb catalyst. Based on the evaluation of characterization and performance test, we confirm that the proposed metallic structured catalyst in this study has high efficient and durability. Therefore, we suggest that the metallic structured catalyst may be a good alternative as a new type of SCR catalyst for marine SCR system.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.5
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• pp.50-60
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• 2010

For the last half a century, the personal computer and software industries have been prosperous due to the incessant evolution of computer systems. In the 21st century, the embedded system market has greatly increased as the market shifted to the mobile gadget field. While a lot of multimedia gadgets such as mobile phone, navigation system, PMP, etc. are pouring into the market, most industrial control systems still rely on 8-bit micro-controllers and simple application software techniques. Unfortunately, the technological barrier which requires additional investment and higher quality manpower to overcome, and the business risks which come from the uncertainty of the market growth and the competitiveness of the resulting products have prevented the companies in the industry from taking advantage of such fancy technologies. However, high performance, low-power and low-cost hardware and software platforms will enable their high-technology products to be developed and recognized by potential clients in the future. This paper presents such a platform for industrial embedded systems. The platform was designed based on Telechips TCC8300 multimedia processor which embedded a variety of parallel hardware for the implementation of multimedia functions. And open-source Embedded Linux, TinyX and GTK+ are used for implementation of GUI to minimize technology costs. In order to estimate the expected performance and power consumption, the performance improvement and the power consumption due to each of enabled hardware sub-systems including YUV2RGB frame converter are measured. An analytic model was devised to check the feasibility of a new application and trade off its performance and power consumption. The validity of the model has been confirmed by implementing a real target system. The cost can be further mitigated by using the hardware parts which are being used for mass production products mostly in the cell-phone market.

• Journal of the Korean Society of Earth Science Education
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• v.9 no.2
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• pp.199-216
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• 2016

The purpose of this study is to figure out how much gifted science education teachers in charge of the class realize the necessity of individualized curriculum and program for scientifically gifted, to find out the problems of the gifted science educational institutions from exploring them in depth in the light of the reality in the gifted science educational institutions, and to draw implications about the applicable direction of more aggressive individualized curriculum and program for scientifically gifted. I chose 15 people with the incumbent teachers who have ever taught scientifically gifted and have a degree in the gifted education or science subject education as study participants and had a depth interview with them. According to result of the study, 14 of 15 study participants recognized the necessity of individualized education in science should understand the personal requirements according to the tendency of the gifted students and should be a study led by students themselves. Of the problems in gifted science education, teachers regarded the reduction in the financial support as the biggest problem and the vocation and professionalism of teachers were referred as a very important factor. With constraints of time and space, there were plenty of opinions that can't ignore the influence of educational environment associated with the university entrance examination. There were many opinions that there is excessive expansion of the agencies and the target for gifted students, no standardized measurement tools and programs and the lack of the system for the coherent observation as a teacher. Also, the unified curriculum of gifted science education institutions were pointed out as the problem and the individualized programs which were already under way have a lot of weakness and being offered marginally. Thus, from now on, to apply for individualized education of gifted science, teachers demanded optimized education conditions and consistent policy support, and expressed the opinion that there needs of a possible continuous observation system. Besides, the curriculum and programs matched the needs of the students should be taken priority the most, and there were another answers that fellow learning within the cooperative learning can be an alternative of the individualized. Along with that, there were lots of opinions that the treatment to overcome an inferiority complex according to the individualized should be followed.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.93-100
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• 2014

In general, whey obtained from various cheese batches is being reused, so as to improve the texture and to increase the yield and the nutrient value of the various final milk-based products. In fact, re-usage of whey proteins, including whey cream, is a common and routine procedure. Unfortunately, most bacteriophages can survive heat treatments such as pasteurization. Hence, there is a high risk of an increase in the bacteriophage population during the cheese-making process. Whey samples contaminated with bacteriophages can cause serious problems in the cheese industry. In particular, the process of whey separation frequently leads to aerosol-borne bacteriophages and thus to a contaminated environment in the dairy production plant. In addition, whey proteins and whey cream reused in a cheese matrix can be infected by bacteriophages with thermal resistance. Therefore, to completely abolish the various risks of fermentation failure during re-usage of whey, a whey treatment that effectively decreases the bacteriophage population is urgently needed and indispensable. Hence, the purpose of this review is to introduce various newly developed methods and state-of-the-art technologies for removing bacteriophages from contaminated whey and whey products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.904-911
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• 2015

The objective of this study was to investigate the quality characteristics of traditional wine using an radio-frequency identification (RFID) system annexed to a fermenter. In this study, we proposed an RFID-based data transmission scheme for monitoring fermentation of traditional alcoholic beverages. The pH, total acidity, total sugar, soluble sugar, free sugar, alcohol content, and organic acids of were investigated and subjected to fermentation of traditional alcoholic beverages three times. The pH ranged from 7.98, 7.95, and 7.68 at day 0, decreased drastically to 3.31~2.96 at day 2, and then slowly increased to the end point, finally reaching 3.34 at day 20. Acidity tended to increase quickly with time, especially for all samples after day 2. The fermentation environment induced a sudden increase acidity in reactants and indicated a low pH. The total sugars during fermentation quickly decreased to the range of 20.3, 22.43, and 19.2% at day 2, and the slope of reduction steadily decreased to 5.1, 6.1, and 4.8% at day 10. On the other hand, the alcohol content showed the reverse trend as total sugars. The alcohol content also showed the same pattern as total acids, showing the highest alcohol content of 17.3% (v/v) on day 20. In this study on traditional wine fermentation using an RFID system, we showed that pH, soluble sugar, and alcohol content can be adopted as key indicators for quality control and standardization of traditional wine manufacturing.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.148-149
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• 2000

황금배는 1967년에 신고에 이십세기를 교배하여 1977년 1차선발과 1982년 2차선발을 거 쳐 1984년 최종선발, 명명한 품종으로, 당도가 높고 육질이 부드러워서 최근 몇년 사이에 캐 나다, 미국, 호주, 그리고 유럽 지역에서의 수요가 급증하고 있는 수출전망이 매우 밝은 품 종 중의 하나이다(92년 재배면적 lOha 수출량 5. 8M/T, 95년 재배면적 150ha 수출량 2 200.6M/T), 황금배는 비교적 대과이고 과형은 원형에 가까운 편원형으로서 사과 골든처럼 과피가 황금색이고 과육은 연황백색으로 투명하며 보기에 극히 미려한 특징이 있다. 아울러 육질이 유연치밀하고 과즙이 극히 많으며 당도가 높아 13$^{\circ}$ Bx이상, 15도 Bx까지 측정되는 둥 감산이 적화되어 맛이 극히 우수하다. 그러나 이러한 황금배는 동녹, 흑반병 등 병충해로 인한 상품가치의 하락으로 현재 수요를 충족시키지 못하고 있는 실정이다. 1 16세기부터 씌워진 과실봉지는 초기 병해충을 방지할 목적만으로 사용되어 왔지만, 현 재는 방균과 방충의 효과와 함께 자연현상의 최적화를 위한 차광성, 발수성, 투기성을 조절 하며 과실의 외관까지 영향을 미치는 바, 과실봉지의 기능성 부여를 위해서는 고도의 기술 력이 요구되고 있다 하겠다. 상기한 배에 방균방충처리된 과설봉지를 씌워서 재배하면 농 약 살포횟수를 줄이고 배에 농약이 직접 묻지 않아 배의 농약오염을 예방할 수 있으며, 봉 지 안으로의 해충이나 균의 침투를 원천적으로 봉쇄할 수 있다. 그러나 기존의 황금배용 봉 지는 비록 기타 병충해 피해를 방지하는 효과는 있었으나, 동녹을 억제하는 효력이 다소 미 흡하였다. 과피의 비정상적인 코르크화로 인해 발생하는 동녹은 과피의 물리적 할렬과 생리적 장 해에 의해 발생하는 것으로 알려져 있다(永澤 1940). 과실이 비대해짐에 따라 과피의 기공 (과점)이 할렬하면서 코르크화가 진행되는데 그 발생정도나 시기는 배의 품종에 따라 다르 나 일반적으로 코르크화는 기상조건, 특히 습도와 밀접한 관련이 있다고 알려져 있다 황금 배의 재배에 봉지를 적용하면 일반적으로 과피의 코르크화가 억제되는데 그러한 이유는 다 음과 같이 설명할 수 있다. 과실은 하루를 주기로 하여 수축과 팽창을 반복하면서 비대화하 는데 이러한 현상은 과실 내의 수분 조건에 따르는 것으로, 봉지재배의 경우 무대재배보다 단기간에 변화되는 습도의 범위가 좁아 급변을 방지하기에 과점의 할렬이 완화될 수 있다. 즉, 봉지를 씌웅으로서 봉지 내의 대기 환경이 외기보다 안정적으로 유지되고 직사광선이나 농약 및 마찰로부터 과실을 보호해 주기에 동녹이 어느 정도 방지될 수 있는 것이다. 그러나 기존의 황금배봉지는 동녹의 정도를 완화시킬 뿐 완전히 방지할 수 없었으며, 봉지를 적 용한 재배조건에서의 동녹발생 기구를 정확히 이해하지 못했었기에 효과적으로 봉지의 기능 을 개선하는 것이 불가능하였다. 과설의 미려도는 과실의 맛과 함께 그 가치를 결정짓는 중요한 물성으로서 우리나라 황 금배 재배환경과 특성에 알맞은 배봉지의 제작이 선결될 때, 배 품질의 향상, 안정된 공급이 가능하게 될 것이며 아울러 농가의 수업증대와 수출 경쟁력 강화가 이루어질 수 있을 것으로 판단된다. 이러한 측면에서 황금배 재배농가가 당면한 동녹발생의 문제점을 신속한 해결 을 위한 새로운 기능성 국산 황금배 봉지의 개발이 절실히 요구되고 있다. 위와 같은 문제를 해결하기 위하여 본 연구에서는 과실봉지의 종류간에 동녹발생 정도 가 상이한 점에 예의 주시하여 다양한 봉지의 적용실험을 통해 다음과 같은 결과를 얻었다. 황금배의 동녹 발생 정도는 배봉지의 발수성과 투기 및 투습도에 의해 크게 영향받는다. 상기한 바와 같이 과점의 코르크화로 인해 동녹이 발생된다고 할 때, 봉지 내의 습기 및 웅결수의 양은 황금배의 동녹에 중대한 영향을 미친다. 태양광이 내려찍는 낮 시간동안 황 금배는 증산작용을 하며 습기를 배출하는데 봉지 내의 온도가 높은 낮 시간 동안 수분이 습기로 존재하지만 기온이 급격히 떨어지는 일몰 이후에는 상대습도가 높아짐에 따라 결로 현상으로 인해 응결수가 된다. 이때 응결수와 접촉한 과피는 건조한 상태보다 세균의 침입 이 용이할 뿐만 아니라 기공(과점)의 호홉에 지장이 초래됨에 따라 과점의 할렬이 더욱 조 장되어 코르크화를 유발하고 결과적으로 동녹이 발생한다고 판단된다. 따라서 만일에 봉지 의 투기, 투습도가 양호하여 봉지 내의 과다한 수분이 충분히 배출될 수 있었다면, 수분의 응결을 피하고 동녹을 완화시킬 수 있을 것이라 판단되었다.

• Journal of the Korean earth science society
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• v.42 no.3
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• pp.311-324
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• 2021

Recently, ten geosites have been considered in Hwaseong for endorsement as national geoparks, including the Jebudo, Gojeongri Dinosaur Egg Fossils, and Ueumdo geosites. The Jebudo geosite in the southern part of the Seoul metropolitan area has great potential for development as a new geoscience educational site because it has geological, geographical (landscape), and ecological significance. In this study, we described the geological characteristics through field surveys in the Jebudo geosite. We evaluated its potential as a geo-education site based on comparative analysis with other geosites in Hwaseong Geopark. In addition, we reviewed the practical effect of field education at geosites on the essential concepts and critical competence-oriented education emphasized in the current 2015 revised science curriculum. The Jebudo Geosite is geologically diverse, with various metamorphic rocks belonging to the Precambrian Seosan Group, such as quartzite, schist, and phyllite. Various geological structures, such as clastic dikes, faults, joints, foliation, and schistosity have also been recorded. Moreover, coastal geological features have been observed, including depositional landforms (gravel and sand beaches, dunes, and mudflats), sedimentary structures (ripples), erosional landforms (sea cliffs, sea caves, and sea stacks), and sea parting. The Jebudo geosite has considerable value as a new geo-education site with geological and geomorphological distinction from the Gojeongri Dinosaur Egg Fossils and Ueumdo geosites. The Jebudo geosite also has opportunities for geo-education and geo-tourism, such as mudflat experiences and infrastructures, such as coastal trails and viewing points. This geosite can help develop diverse geo-education programs that improve key competencies in the science curriculum, such as critical thinking, inquiry, and problem-solving. Furthermore, by conducting optimized geo-education focused on the characteristics of each geosite, the following can be established: (1) the expansion of learning space from school to geopark, (2) the improvement of understanding of specific content elements and linkage between essential concepts, and (3) the extension of the education scope throughout the earth system. There will be positive impacts on communication, participation, and lifelong learning skills through geopark education.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.3
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• pp.199-208
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• 2019

As the number of available satellites increases and technology advances, image information outputs are becoming increasingly diverse and a large amount of data is accumulating. In this study, we propose a change detection method for high-resolution satellite images that uses transfer learning and a deep learning network to overcome the limit caused by insufficient training data via the use of pre-trained information. The deep learning network used in this study comprises convolutional layers to extract the spatial and spectral information and convolutional long-short term memory layers to analyze the time series information. To use the learned information, the two initial convolutional layers of the change detection network are designed to use learned values from 40,000 patches of the ISPRS (International Society for Photogrammertry and Remote Sensing) dataset as initial values. In addition, 2D (2-Dimensional) and 3D (3-dimensional) kernels were used to find the optimized structure for the high-resolution satellite images. The experimental results for the KOMPSAT-3A (KOrean Multi-Purpose SATllite-3A) satellite images show that this change detection method can effectively extract changed/unchanged pixels but is less sensitive to changes due to shadow and relief displacements. In addition, the change detection accuracy of two sites was improved by using 3D kernels. This is because a 3D kernel can consider not only the spatial information but also the spectral information. This study indicates that we can effectively detect changes in high-resolution satellite images using the constructed image information and deep learning network. In future work, a pre-trained change detection network will be applied to newly obtained images to extend the scope of the application.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.324-332
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• 2019

Most countries including Korea and Indonesia have strong policy for implementing biofuels like biodiesel. Shortage of the oil feedstock is the main barrier for increasing the supply of biodiesel fuel. In this study, in order to improve the stability of feedstock supply and lower the biodiesel production cost, the feasibility of biodiesel production using two types of Indonesian tropical crop oils, pressed at different harvesting times, were investigated. R. Trisperma oils, a high productive non-edible feedstocks, were investigated to produce biodiesel by esterification and transesterification because of it's high impurity and free fatty acid contents. the kindly provided oils from Indonesia were required to perform the filtering and water removal process to increase the efficiency of the esterificaton and transesterification reactions. The esterification used heterogeneous acid catalyst, Amberlyst-15. Before the reaction, the acid value of two types oil were 41, 17 mg KOH/g respectively. After the pre-esterification reaction, the acid value of oils were 3.7, 1.8 mg KOH/g respectively, the conversions were about 90%. Free fatty acid content was reduced to below 2%. Afterwards, the transesterification was performed using KOH as the base catalyst for transesterification. The prepared biodiesel showed about 93% of FAME content, and the total glycerol content was 0.43%. It did not meet the quality specification(FAME 96.5% and Total glycerol 0.24%) since the tested oils were identified to have a uncommon fatty acid, generally not found in vegetable oils, ${\alpha}$-eleostearic acid with much contents of 10.7~33.4%. So, it is required to perform the further research on reaction optimization and product purification to meet the fuel quality standards. So if the biodiesel production technology using un-utilized non-edible feedstock oils is successfully developed, stable supply of the feedstock for biodiesel production may be possible in the future.