• Clean Technology
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• v.20 no.1
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• pp.42-50
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• 2014

In this study, the $Mg(OH)_2$ slurry was made form ferro-nickel slag and then used for $CO_2$ sequestration. The experiments were in the order as leaching step, precipitation, carbonation experiments. According to the leaching results, the optimal leaching conditions were $H_2SO_4$ concentration of 1 M and the temperature of 333 K. In the $Mg(OH)_2$ manufacturing step, NaOH was added to increase the pH upto 8, the first precipitation was confirmed as $Fe_2O_3$. After removal the first precipitation, the pH was upto 11, the $Mg(OH)_2$ was generated by XRD analysis. The $Mg(OH)_2$ slurry was used for $CO_2$ sequestration. The pseudo-second-order carbonation model was used to apply for $CO_2$ sequestration. The $CO_2$ sequestration rate was increased by the $CO_2$ partial pressure and temperature. However, $CO_2$ sequestration rate was decreased when temperature upto 323 K. After $CO_2$ sequestrated by $Mg(OH)_2$, the $CO_2$ can be sequestrated stable as $MgCO_3$. This study also presented optimal sequestration condition was the pH upto 8.38, the maximum $MgCO_3$ can be generated. This study can be used as the basic material for $CO_2$ sequestration by ferro-nickel slag at pilot scale in the future.

• Progress in Medical Physics
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• v.25 no.4
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• pp.210-217
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• 2014

This study investigated the dosimetric effects of different dose calculation algorithm for lung stereotactic ablative radiotherapy (SABR) using flattening filter-free (FFF) beams. A total of 10 patients with lung cancer who were treated with SABR were evaluated. All treatment plans were created using an Acuros XB (AXB) of an Eclipse treatment planning system. An additional plans for comparison of different alagorithm recalcuated with anisotropic analytic algorithm (AAA) algorithm. To address both algorithms, the cumulative dose-volume histogram (DVH) was analyzed for the planning target volume (PTV) and organs at risk (OARs). Technical parameters, such as the computation times and total monitor units (MUs), were also evaluated. A comparison analysis of DVHs from these plans revealed the PTV for AXB estimated a higher maximum dose (5.2%) and lower minimum dose (4.2%) than that of the AAA. The highest dose difference observed 7.06% for the PTV $V_{105%}$. The maximum dose to the lung was also slightly larger in the AXB plans. The percentate volumes of the ipsilateral lung ($V_5$, $V_{10}$, $V_{20}$) receiving 5, 10, and 20 Gy were also larger in AXB plans than for AAA plans. However, these parameters were comparable between both AAA and AXB plans for the contralateral lung. The differences of the maximum dose for the spinal cord and heart were also small. The computation time of AXB plans was 13.7% shorter than that of AAA plans. The average MUs were 3.47% larger for AXB plans than for AAA plans. The results of this study suggest that AXB algorithm can provide advantages such as accurate dose calculations and reduced computation time in lung SABR plan using FFF beams, especially for volumetric modulated arc therapy technique.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.267-271
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• 2013

Test bed studies with highly efficient amine $CO_2$ solvent (KoSol-4) developed by KEPCO research institute were performed. For the first time in Korea, evaluation of post-combustion $CO_2$ capture technology to capture 2 ton $CO_2$/day from a slipstream of the flue gas from a coal-fired power station was performed. Also the analysis of solvent regeneration energy was conducted to suggest the reliable performance data of the KoSol-4 solvent. For this purpose, we have tested 5 campaigns changing the operating conditions of the solvent flow rate and the stripper pressure. The overall results of these campaigns showed that the $CO_2$ removal rate met the technical guideline ($CO_2$ removal rate: 90%) suggested by IEA-GHG and that the regeneration energy of the KoSol-4 showed about 3.0~3.2 GJ/$tCO_2$ which was, compared to that of the commercial solvent MEA (Monoethanolamine), about 25% reduction of regeneration energy. Based on these results, we could confirm the good performance of the KoSol-4 solvent and the $CO_2$ capture process developed by KEPCO research institute. And also it was expected that the cost of $CO_2$ avoided could be reduced drastically if the KoSol-4 is applied to the commercial scale $CO_2$ capture plant.

• Journal of Chest Surgery
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• v.32 no.6
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• pp.536-542
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• 1999

Background: The purpose of this study is to improve the quality of the diagnostic procedures in the preoperative evaluation so as to reduce the unnecessary thoracotomy and to ensure resectability in non-small cell lung cancer. Material and Method: Of 616 patients who underwent thoracotomy for primary lung cancer from January 1990 to December 1996, 59 patients(9.6%) turned out to have inoperable lesions after the thoracotomy. We reprospectively reviewed the bronchoscopic findings, methods of tissue diagnosis, CT scans, pulmonary function test and lung perfusion scan, reasons for nonresectability, and adjuvant therapy, and then followed up on the survival rate after exploratory thoracotomy. Result: The cell types were squamous cell carcinoma in 38, adenocarcinoma in 15, large cell carcinoma in 3 and others in 3. Primary loci were RUL in 20, RML in 6, RLL in 8, LUL in 13, LLL in 4 and others in 8. The reasons for non-resectability were various; direct tumor invaison to mediastinal structures(n=41), seeding on pleural cavity(n=8), poor pulmonary function(n=2), invasions to extranodal mediastinal lymph node(n=2), technical non- resectability due to extensive chest wall invasion (n=3), small cell carcinoma (n=1), malignant lymphoma(n=1), and multiple rib metastases(n=1). In the follow-up of 58 patients, 1-year survival rate was 55.2% and 2-year survival rate was 17.2% and the mean survival time was 14 months. When compared according to cell types or postoperative adjuvant therapeutic modalities, no significant difference in the survival rates were found. The squamous cell carcinoma was frequently accompanied by local extension to contiguous structures and was the main cause of non-resectability. In adenocarcinoma, pleural seeding with malignant effusion was frequently encountered, and was the major reason for non-resectability. Conclusion: These data revealed that if appropriate preoperative diagnostic tools had been available, many unnecessary thoracotomies could have been avoided. Both the use of thoracoscopy in selected cases of adenocarcinoma and the more aggressive surgical approach to the locally advanced tumor could reduce the incidence of unnecessary thoracotomies for non-small cell lung cancers.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.722-732
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• 2021

Purpose: Due to the coronavirus infection-19 (COVID) pendemics, all educational institutions were required to provide full non-face-to-face real-time education, and fire officials were required to provide fire-fighting education by applying non-face-to-face education. In this difficult situation, the National Fire Service Academy tries to find the direction of the non-face-to-face real-time education and suggest ways to improve it through a survey of the status of non-face-to-face real-time education conducted by the NFSA to fire officials. Method: A survey was conducted on fire officials under the theme of "Consciousness Survey for Improving the Quality and Specialization of Non-face-to-face Real-Time Remote Education" and an in-depth analysis was conducted based on the results. Result & Conclusion: First, professors or educational operators shall actively utilize remote education programs suitable for educational characteristics by utilizing various programs. Second, a dedicated notebook for non-face-to-face training should be provided to provide an educational environment where all learners can participate in the training without difficulty. Third, in the case of education and training that requires the use of equipment due to the nature of fire officials' education and training, it is necessary to consider it as a non-face-to-face training place by arranging educational equipment at each fire station. Fourth, it is hard to expect a satisfactory educational effect to cope with practical education with theoretical education. Therefore, facilities and programs that enable non-face-to-face real-time hands-on training should be developed. It is worth considering the proper combination of face-to-face education while maintaining the social distance as much as possible until such non-face-to-face training is possible. Fifth, non-face-to-face education is considered to have high eye fatigue due to the light and electromagnetic waves of the computer screen, and as time goes by, the concentration level decreases. Therefore, it is necessary to form an education time to reduce the eye fatigue of learners and increase concentration through proper class and rest time. Finally, professors should operate a learner participation-oriented education that allows professors and learners to interact rather than one-sided knowledge transfer education. In addition, technical problems of non-face-to-face remote education should be thoroughly prepared through preliminary system checks to ensure that education is not disrupted.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.2 no.3
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• pp.33-60
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• 2007

This study alms to analyze the entrepreneur characteristics of founder on enterprise performance from the strategic viewpoint as well as features of founder of small firms such as background feature of founder, psychological features and management skill. As considered by Background features of founder include educational background of founder, his experience in business creation, consultation or course related to business creation. This study verified the effects of factor which business performance (financial, non financial) on small firms. Also, this study considered psychological features of founder include achievement desire, risk-free propensity, level of patience on vagueness and control position. And it analyzed that between such factors and performance of small firms were examined in related. In the mean time, management ability of founder, entrepreneur ability, technical and function ability were considered for management skill of founder and alalyzed effect of the factors on performance of small firm were examined. Effects of strategic intention of founder of small firm were analyzed by the strategic viewpoint. At this time, strategy of small firm was divided into product-service reform differentiation strategy, marketing differentiation strategy and cost leadership strategy. This study distributed questionnaire on CEO of small firms in Daejeon and Chungnam area for accomplish the study objective and it collected a total of 145 copies of questionnaires. As a result of analyzing collected questionnaire, this study deduced the following study results and suggestions. First, results different from those of existing studies were found Since sales, net income and profit rate of small firm were not high cause economic depression on the whole. Second, entrepreneur ability was found to be required for success of business creation. Entrepreneur ability of founder was the factor that affects both financial and non - financial performance of small firm. As such, entrepreneur ability can be regarded as the most important factor for success in business creation of small firm. Accordingly, entrepreneur ability is the most important source for success in business creation of small firm. Third, strategy of small firm was found to be the important factor that affects the non-financial performance even if it could not give significant effects on financial performance. Thus, product service reform differentiation strategy, marketing differentiation strategy and cost leadership strategy have significant effects on non - financial performance of small firm. Accordingly, it is required to operate small firm with strategic mind - set for small firm to achieve success. This study analyzed the effects of feature of founder and strategy of small firm on business performance of small firm through practical analysis on small firms in Daejeon and Chungnam area, and deduced meaningful results. However, Since this study collected data on small firms in Daejeon and Chungnam only, there is a limit in generalizing the results of this study to all small firms in Korea. Companies answering to this questionnaire process were mainly wholesale and retail service companies. In addition, there is a limit in that it failed to analyze feature of representative type of industry due to limit in number of sample, it is required to divide representative type of industry and to compare and analyze types of industry in future studies.

• Journal of Korean Home Economics Education Association
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• v.21 no.1
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• pp.89-106
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• 2009

The purpose of this study was to investigate the perspectives on curriculum of secondary school home economics(HE) teachers, the HE teacher efficacy level, and the correlation between their perspectives on HE curriculum and the HE teacher efficacy. A questionnaire survey was carried out to the 500 HE teachers from middle and high schools across the nation, 215 questionnaires were used in the final analysis. The findings of this study were as follows: First, most of HE teachers had the biggest interest in interpretative perspective and some teachers had a interest in critical perspective. On the other hand, a few teachers only had a interest in technical curriculum perspective. Second, HE teachers who worked in the big cities tended to be more interested in interpretative perspective than those who worked in small cities. HE teachers from 25 to 40 years olds tended to be more interested in critical perspective than those who were more than 50 years old. Also, HE teachers with less than 15 years of experience tended to be more interested in critical perspective than those who had worked for more than 15 years. Third, the average of the HE teacher efficacy level was 3.69. The efficacy level of studying support was the highest. Then came class support, environment support, instruction strategy, and demands alternation in order. Fourth, there was moderate correlation between the interpretative perspective on curriculum of middle and high school HE teachers and teacher efficacy level in comparison with other curriculum perspectives.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.457-468
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• 2020

Problems arising during pile design works for plant construction, civil and architecture work are mostly come from uncertainty of geotechnical characteristics. In particular, obtaining the N-value measured through the Standard Penetration Test (SPT) is the most important data. However, it is difficult to obtain N-value by drilling investigation throughout the all target area. There are many constraints such as licensing, time, cost, equipment access and residential complaints etc. it is impossible to obtain geotechnical characteristics through drilling investigation within a short bidding period in overseas. The geotechnical characteristics at non-drilling investigation points are usually determined by the engineer's empirical judgment, which can leads to errors in pile design and quantity calculation causing construction delay and cost increase. It would be possible to overcome this problem if N-value could be predicted at the non-drilling investigation points using limited minimum drilling investigation data. This study was conducted to predicted the N-value using an Artificial Neural Network (ANN) which one of the Artificial intelligence (AI) method. An Artificial Neural Network treats a limited amount of geotechnical characteristics as a biological logic process, providing more reliable results for input variables. The purpose of this study is to predict N-value at the non-drilling investigation points through patterns which is studied by multi-layer perceptron and error back-propagation algorithms using the minimum geotechnical data. It has been reviewed the reliability of the values that predicted by AI method compared to the measured values, and we were able to confirm the high reliability as a result. To solving geotechnical uncertainty, we will perform sensitivity analysis of input variables to increase learning effect in next steps and it may need some technical update of program. We hope that our study will be helpful to design works in the future.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.5
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• pp.783-790
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• 2009

This study was conducted to investigate the recognition and uses of Angelica gigas Nakai. A survey methodology was employed consisted of 37.8% males and 62.2% females from the Seoul and Kyunggido area. The main results are as follows: The older generation have liked and eaten Angelica gigas Nakai rather than the young. The most popular reason provided for the preference of Angelica gigas Nakai was good health benefits. People indicating a dislike for Angelica gigas Nakai had little previous experience of eating this plant. The purchasing main place is appeared the supermarket and traditional market. Angelica gigas Nakai was acknowledged as having the following characteristics 'to do excellent nutrition' (3.82), 'natural food' (3.76), 'to doing for the anti-cancer and anti-oxidization' (3.70), 'good for anemia and women, diseases' (3.64), and 'good for anodyne and diuretic effect' (3.57), but was not associated with 'price is cheap' (3.02) and 'to difficult for buy' (3.10). Recognition and eating experience was low for Angelica gigas Nakai kimchi and rice bread, bread, sauce and healthy drink added with Angelica gigas Nakai, but the opinion of the taste appeared highly.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.391-396
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• 2016

The absorption efficiency of amine $CO_2$ absorbent (KoSol-5) developed by KEPCO research institute was evaluated using a 0.1 MW test bed. The performance of post-combustion technology to capture two tons of $CO_2$ per day from a slipstream of the flue gas from a 500 MW coal-fired power station was first confirmed in Korea. Also the analysis of the absorbent regeneration energy was conducted to suggest the reliable data for the KoSol-5 absorbent performance. And we tested energy reduction effects by improving the absorption tower inter-cooling system. Overall results showed that the $CO_2$ removal rate met the technical guideline ($CO_2$ removal rate : 90%) suggested by IEA-GHG. Also the regeneration energy of the KoSol-5 showed about $3.05GJ/tonCO_2$ which was about 25% reduction in the regeneration energy compared to that of using the commercial absorbent MEA (Monoethanolamine). Based on current experiments, the KoSol-5 absorbent showed high efficiency for $CO_2$ capture. It is expected that the application of KoSol-5 to commercial scale $CO_2$ capture plants could dramatically reduce $CO_2$ capture costs.