• Clean Technology
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• v.15 no.2
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• pp.81-90
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• 2009

In this study various cleaning evaluation methods were tested and comparatively evaluated to help cleaning industry. In order to select alternative cleaning agents objectively and systematically, various cleaning evaluation methods such as gravimetric, optically simulated electron emission (OSEE), contact angle, and analytical instrument methods were employed for cleaning contaminants such as flux, solder and grease. The analytical instruments used in this work were Fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-VIS) and high performance liquid chromatography (HPLC). The gravimetric method was able to measure cleaning efficiencies easily and simply, but it was not easy to analyze them precisely because of its limitation in the gravimetric measurement. However, the OSEE technique was able to measure quickly and precisely the clean ability of cleaning agents in comparison with the gravimetric method. The contact angle method was found to be necessary for taking special precaution in its application to the cleaning evaluation due to possible formation of tiny organic film on the substrate surface which might be generated from contaminants and cleaning agents. In case of precision analysis that cannot be done by gravimetric method, fine analytical instruments such as UV-VIS, FTIR and HPLC could be used in analyzing trace amount of flux, solder and grease quantitatively, which were extracted from the surface by special solvents.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.8-18
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• 2023

Increasing of energy demand due to the rapid growth of global population and the development of world economy has inevitably resulted in the continuously increase of fossil fuel usage in the world. However, highly dependence on fossil fuels has necessarily brought about critical environmental issues and challenges such as severe air pollutions and rapid global warming. In order to settle these environmental and energy problems, clean energy generations in the conventional combustion processes have widely adapted in the world. In particular, novel thermochemical conversion processes such as pyrolysis and gasification have rapidly been applied for generating clean energy. Fluidized bed technologies having advantages such as various fuel use, easy continuous operation, high heat and material transfer, isothermal operation, and lower operation temperature are widely adopted and used because they are suitable for thermochemical energy conversion. The latest research trends and important findings in the thermo-chemical conversion process with fluidized bed technologies are summarized in this review. Also, the need for research such as layered materials and substances to reduce fine dust (biomass, natural resource waste, etc.) was suggested. Through this, it is intended to increase interest and understanding in fluidized bed technology and to present directions for solving future challenges in fluidized bed process technology development.

• Journal of the Institute of Convergence Signal Processing
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• v.23 no.2
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• pp.107-114
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• 2022

In order to classify 3D film images as right or wrong, it is necessary to detect the pattern in a 3D film image. However, if the contrast of the pixels in the 3D film image is low, it is not easy to classify as the right and wrong 3D film images because the pattern in the image might not be clear. In this paper, we propose a method of classifying 3D film images as right or wrong by comparing the width at a specific frequency of each histogram after obtaining the histogram. Since, it is classified using the width of the histogram, the analysis process is not complicated. From the experiment, the histograms of right and wrong 3D film images were distinctly different, and the proposed algorithm reflects these features, and showed that all 3D film images were accurately classified at a specific frequency of the histogram. The performance of the proposed algorithm was verified to be the best through the comparison test with the other methods such as image subtraction, otsu thresholding, canny edge detection, morphological geodesic active contour, and support vector machines, and it was shown that excellent classification accuracy could be obtained without detecting the patterns in 3D film images.

• The Journal of the Acoustical Society of Korea
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• v.42 no.2
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• pp.133-142
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• 2023

The office environment is changing according to work types, Information Technology (IT) advancements, and the Coronavirus disease (COVID)-19 situation. In order for office space users to perform their tasks comfortably and efficiently, it is necessary to secure individual privacy as well as easy communication among members. In Korea, the demand for improving the acoustic performance of office spaces is also increasing, but the related performance criteria and guidelines have not been established. In this study, standardization of office space acoustic performance measurement and evaluation methods and European countries' acoustic performance criteria were compared and reviewed. It is proposed to comprehensively review international standardization trends and acoustic performance standards in each country and to establish and utilize criteria for evaluating the acoustic performance and satisfaction of office spaces in Korea through our survey. Considering the international standardization direction and compatibility with communication and Public Address (PA) systems, it is appropriate to establish criteria using the speech transmission index or Speech Transmission Index (STI) application index. This criterion will be highly utilizable and compatible. In addition, since the office furniture industry is interested in improving the acoustic performance of office space, it is necessary to establish a labelling system for speech level reduction of office furniture.

• Journal of Korean Library and Information Science Society
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• v.53 no.1
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• pp.55-79
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• 2022

In this study, the current status of operation was analyzed with a view to analyze the areas in need of improvement and the status of portals of similar institutions. Based on which, a proposal was made to help improve the function of utilization as well as search the products of studies by and for the research institutes funded by the government having jurisdiction by applying the information service technology developing in line with the fourth industrial revolution for the purposes of aiding and fostering with efficiency toward achieving the goal of establishment for such institutes, while strengthening the utility of NKIS. First, in order to secure the membership, it is necessary to find the targets for policy information and promotion, and it is also necessary to increase the demand for policy information, such as by preparing the people friendly policy reports, infographics, and information delivery in an easy manner. Second, it is necessary to provide customized services in the manner which reinforces reports and policy data on the social issues and education topics, which are among the interests of the primary user base by considering the ratio of visiting occupations. Third, for the diversification and expansion of video data services, it is necessary to prepare alternatives, such as by setting regulations and encouraging the institutions of jurisdiction to upload the video data. Fourth, it will be necessary to improve the overall public relations service. It is also necessary to proceed with the NKIS' publicity webtoon serialization with the latest contents or abolish the current webtoon promotion, while it is necessary to derive the plans for the efficient implementation of the contest, further to the need to discuss the secondary publicity after the contest rather than halting after it.

• Journal of Digital Convergence
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• v.20 no.3
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• pp.325-331
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• 2022

As IoT devices are used in various ways in an edge network environment, multiple studies are being conducted that utilizes the information collected from IoT devices in various applications. However, it is not easy to apply accurate IoT data immediately as IoT data collected according to network environment (interference, interference, etc.) are frequently missed or error occurs. In order to minimize mistakes in IoT data collected in an edge network environment, this paper proposes a management technique that ensures the reliability of IoT data by randomly generating signature values of IoT data and allocating only Security Information (SI) values to IoT data in bit form. The proposed technique binds IoT data into a blockchain by applying multiple hash chains to asymmetrically link and process data collected from IoT devices. In this case, the blockchainized IoT data uses a probability function to which a weight is applied according to a correlation index based on deep learning. In addition, the proposed technique can expand and operate grouped IoT data into an n-layer structure to lower the integrity and processing cost of IoT data.

• Health Policy and Management
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• v.33 no.2
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• pp.173-184
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• 2023

Background: The coronavirus disease 2019 pandemic has been challenging the healthcare service, i.e., the vitalization of the point of care accompanying self-testing in vitro diagnostic medical devices (IVDs). This study aims to suggest priority criteria to classify self-testing IVDs using the analytic hierarchy process technique. Methods: Two dimensions of the characteristics embedded in the IVDs and the diseases to be diagnosed with self-testing IVDs were parallelly considered and independently investigated. In addition, three expert panels consisting of laboratory medical doctors (n=11), clinicians (n=10), and citizens (n=11) who have an interest in the selection of self-testing IVDs were asked to answer to questionnaires. Priorities were derived and compared among each expert panel. Results: First of all, ease of specimen collection (0.241), urgency of the situation (0.224), and simplicity of device operation (0.214) were found to be the most important criteria in light of the functional characteristics of self-testing IVDs. Medical doctors valued the ease of specimen collection, but the citizen's panel valued self-management of the disease more. Second, considering the characteristics of the diseases, the priority criteria were shown in the order of prevalence of diseases (0.421), fatality of disease (0.378), and disease with stigma (0.201). Third, medical doctors responded that self-testing IVDs were more than twice as suitable for non-communicable diseases as compared to communicable diseases (0.688 vs. 0.312), but the citizen's group responded that self-testing IVDs were slightly more suitable for infectious diseases (0.511 vs. 0.489). Conclusion: Our findings suggested that self-testing IVDs could be primarily classified as the items for diagnosis of non-communicable diseases for the purpose of self-management with easy specimen collection and simple operation of devices, taking into account the urgency of the situation as well as prevalence and fatality of the disease.

• Composites Research
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• v.36 no.3
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• pp.186-192
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• 2023

Recently, in the field of railway vehicles, interest in the use of composite materials for weight reduction and transportation efficiency is increasing. Accordingly, research and commercialization development to apply composite materials to various vehicle parts are being actively conducted, and evaluation is conducted centering on post-measurement such as mechanical performance evaluation of finished products to verify quality when composite materials are applied. However, the analysis of heat and stress generated during the molding process of composite materials, which are factors that greatly affect manufacturing quality, is insufficient. Therefore, in this study, in order to verify the molding quality of composite parts for railway vehicles, the molding quality analysis was conducted for the two types of composite interior panels (laminate panel and sandwich panel) that are most actively used. To this end, temperature and strain changes were monitored during the molding process by using an FBG fiber optic sensor, which is easy to apply to the inside of the composite, and the residual strain value generated after molding was completed was measured. As a result, it was confirmed that overheating and excessive residual stress did not occur, thereby verifying the excellent molding quality of the composite interior panel for railway vehicles.

• Journal of Christian Education in Korea
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• v.73
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• pp.117-137
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• 2023

This is a case study of an extra-curricular program that designed and implemented maker education based on design thinking to foster a Christian worldview. The program was designed at K university in the course of 10 sessions as following stages; tinkering, providing a special lecture for motivation, finding issues, empathizing, making, sharing and reflecting. A total of 15 students in 5 teams participated in the program, progressed through each stage in the process of solving the problems they found around them so that their neighbors and the creative world could become better. As a result of operating this program, the participants became concerned about their neighbors and community and reflected on the change of perspective of the world from a Christian worldview. As a suggestion for follow-up research and projects, to develop a model of maker education based on design thinking for cultivating a Christian view of the world is proposed in order to support to easy design and management of the program even if there is a lack of professional related knowledge and experience. In addition, it is needed to develop a manual and guide book including a facilitator's role and an assessment tool like a rubric that can give feedback on the performance of the program and make improvement.

• Journal of the Korean Society of Food Culture
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• v.25 no.3
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• pp.270-284
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• 2010

The objective of this study was to familiarize people with the native local food of Chungnam Province by developing its regional food as a culture resource. Native Local Food Search and luxury itemization based on regionally-characterized stories enhances self-perception of the national culture, promotes appropriate local images to the public, and contributes to the local economy by increasing regional tourism. Therefore, this study researched local stories of cultural significance, that is, those connected to the history and originality of Chungnam Province, and developed contents related to Chungnam native local food. Features of the native local food were introduced by a story telling method in order to appeal to the five senses. The story was composed for easy understanding of the value of food, and the brand image of Chungnam was developed based on representative historical stories of the region. In this study, the following were developed as representative images of Chungnam: 'Royal meal table of King Moo-ryung' in Kongju was presented by recomposing the story of King Moo-ryung, a famouns king of the Baekje era; 'Mong-yoo-do-won's rice meal table' was introduced via Mongyoo-do-won's painting by Kyeon An, a famous painter of the Chosun era who was born in Seosan. The 'Royal meal table of King Moo-ryung' was set with food made from local farm products, demonstrating the flavor and elegance of the Baekje era. 'Mong-yoo-do-won's rice meal table' resembled Kyeon An's Mong-yoo-do-won-do, which has a background featuring early spring. The rice table was designed to remind people of a flamboyant painting like a scattered peach blossom leaf in the early spring. To verify the health effectiveness of each rice table, the function of each ingredient was investigated through 'Sik-ryo-chan-yo:a dietary treatment', which was published by Soon-Ui Cheon during the Chosan era. According to the results, most of ingredients are certainly beneficial to health, as was recognized in the early Choson era.