• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.606-612
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• 2022

Relatively high indoor CO₂ concentration (>1,000 ppm) has a negative impact on human health. In this work, indoor CO₂ adsorbent was developed by impregnating KOH or K₂CO₃ on commercial activated carbon, named as KOH/AC and K₂CO₃/AC. Commercial activated carbon (AC) showed relatively high BET surface area (929 m²/g) whereas KOH/AC and K₂CO₃/AC presented lower BET surface area of 13.6 m²/g and 289 m²/g. Two experimental methods of TGA (2,000 ppmCO₂, weight basis) and chamber test (initial concentration: 2,000 ppmCO₂, CO₂ IR analyzer) were used to investigate the adsorption capacity. KOH/AC and K₂CO₃/AC exhibited similar adsorption capacities (145~150 mg_CO2/g), higher than K₂CO₃/Al+Si supports adsorbent (84.1 mg_CO2/g_sample). Similarly, chamber test also showed similar trend. Both KOH/AC and K₂CO₃/AC represented higher adsorption capacities (KOH/AC: 93.5 mg_CO2/g K₂CO₃/AC: 94.5 mg_CO2/g_sample) K₂CO₃/Al+Si supports. This is due to the KOH or K₂CO₃ impregnation increased alkaline active sites (chemical adsorption), which is beneficial for CO₂ adsorption. In addition, the regeneration test results showed both K-based adsorbents pose a good regeneration and reusability. Finally, the current study suggested that both KOH/AC and K₂CO₃/AC have a great potential to be used as CO₂ adsorbent for indoor CO₂ adsorption.

• Korean small business review
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• v.42 no.3
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• pp.221-243
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• 2020

The purpose of this study is to research the effects of desire for independence, possibility of start-up success and employment stability to the push-entrepreneurship through the push-entrepreneurship by a survey of employees in the middle age. The purpose of the creating start-up environment was encouraged the qualitative expansion of opportunity-driven start-up rather than the quantitative expansion of necessity-driven start-up for the economic growth and expanding employment. In spit of the employees had their own careers, skills, opportunities and market-experiences, In reality it is necessity-driven start-up that the quantitative expansion. The purpose of this study was to reflect process change by desire for independence, push-entrepreneurship and pull-entrepreneurship based on the possibility of start-up success and employment stability perceived by individual founders, changed process factor rather than the fixed result factor. The results are as follows. First, it was found that desire for independence makes a positive (+) effect on the pull-entrepreneurship and the push-entrepreneurship. Second, it was found that the possibility of start-up success makes a positive (+) effect on the pull-entrepreneurship and not effect on push-entrepreneurship. third, it was found that the employment stability makes a positive (+) effect on the pull-entrepreneurship and not effect on the push-entrepreneurship. Forth, it was found that desire for independence makes a positive (+) effect on the pull-entrepreneurship and mediating negative (-) effect on the push-entrepreneurship. The implication of this study was that potential entrepreneurs with desire for independence, rather than necessity-driven start-up due to unemployment, could be developed as pull-entrepreneurship improved the situation of push-entrepreneurship. In addition, it seems that entrepreneurship education and activation of entrepreneurship programs for employee with desire for independence expand opportunity-driven start-up after retirement.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.594-600
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• 2021

The purpose of this study is to observe the period of mating calls of cicadas in South Korea to identify the emergence period and geographic distribution for each cicada species. The study sites were 19 protection areas nationwide. The mating calls of cicadas were collected over the 12 months of 2019. A bioacoustics measuring device was installed to record the mating calls of cicadas in WAV, 44,100Hz format for 1 minute every hour. The temperature was recorded once or twice every hour using a micro-meteorological measuring device. Nine species of Korean cicadinae were studied. The start and end periods of mating calls were recorded for each cicada species for the subsequent analysis. The analysis results showed that nine cicada species appeared in the 19 protection areas. The chronological order of mating call periods for each species was as follows: Cryptotympana atrata (7/12 - 9/30), Meimuna opalifera (7/27 - 10/20), Hyalessa fuscata (7/25 - 10/9), Graptopsaltria nigrofuscata (7/28 - 9/5), Platypleura kaempferi (7/3 - 9/29), Suisha coreana (9/14 - 10/30), Leptosemia takanonis (6/26 - 8/2), Auritibicen intermedius (7/27 - 9/28), and Meimuna mongolica (8/8 - 9/11). The mating call period was between 35 (Meimuna mongolica) and 89 (Platypleura kaempferi) days, with the average being 62 days. The elevation above sea level for the habitats of each species was as follows: 5 - 386 m for Cryptotympana atrata, 7 - 759 m for Meimuna opalifera, 7 - 967 m for Hyalessa fuscata, 42 - 700m for Graptopsaltria nigrofuscata, 7 - 700 m for Platypleura kaempferi, 5 - 759 m for Suisha coreana, 7 - 759 m for Leptosemia takanonis, 397 - 967 m for Auritibicen intermedius, and 7 - 42 m for Meimuna mongolica. The average temperature of the habitats of each species was as follows: 23.9℃ for Cryptotympana atrata, 21.8℃ for Meimuna opalifera, 22℃ for Hyalessa fuscata, 23℃ for Graptopsaltria nigrofuscata, 22.9℃ for Platypleura kaempferi, 14.6℃ for Suisha coreana, 20.6℃ for Leptosemia takanonis, 19.3℃ for Auritibicen intermedius, and 24.4℃ for Meimuna mongolica. In terms of the habitat distribution of species, Meimuna opalifera, Hyalessa fuscata, and Platypleura kaempferi were distributed in more than 15 protection sites. Cryptotympana atrata was distributed in the lowlands in the southwest. Graptopsaltria nigrofuscata was distributed in the western area of the Korean Peninsula. Suisha coreana was distributed in areas excluding high mountain areas and parts of the southeast area. Leptosemia takanonis was distributed in areas near the mountains. Auritibicen intermedius was distributed locally in the high mountain areas. Meimuna mongolica was distributed locally in flat wetlands.

• Journal of Korean Home Economics Education Association
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• v.33 no.4
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• pp.85-101
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• 2021

The purpose of this study was to make suggestions for improvement by analyzing the activity tasks in the clothing life area in middle school 「Technology & Home Economics」 textbooks of the 2015 revised curriculum. For this purpose, the multiple intelligence teaching-learning strategy analysis criteria were reconstructed and used for analysis. The activity tasks of the clothing life area of 「Technology & Home Economics I」 textbooks from 12 different publishers were analyzed based on the reconstructed analysis criteria, and the content validity was verified by 11 experts. The content validity, assessed by CVI was 0.94. According to the results, the logical·mathematical intelligence accounted for the highest proportion with 31.02%, followed by linguistic intelligence(23.81%), visual/spatial intelligence(17.08%), intrapersonal intelligence(14.71%), interpersonal intelligence(5.79%), bodily/kinesthetic intelligence(5.22%), naturalistic intelligence(2.37%), and musical intelligence(0.00%). The results showed that the teaching-learning strategies most frequently implemented in clothing life area were logical/mathematical intelligence, linguistic intelligence, visual/spatial intelligence, and intrapersonal intelligence. On the other hand, teaching-learning strategies related to interpersonal intelligence, bodily/kinesthetic intelligence, and naturalistic intelligence were used at a relatively low proportion. Therefore, it is recommended to expand the teaching-learning strategies of interpersonal, bodily/kinesthetic, naturalistic and musical intelligence, for a more balanced intelligence development of students.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.6
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• pp.17-29
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• 2021

Recently, as social distancing have been raised due to the re-spread of COVID-19, the number of serial entrepreneurs who are closing their business is rapidly increasing. Learning from failure is a source of success, but business failure can result in psychological and economic losses and negative emotions of the serial entrepreneur. At this point, it is very important to find a way to recover the negative emotions caused by business failures of serial entrepreneurs. Recently, a strategic model has emerged to deal with the negative emotions of grief caused by business failures of serial entrepreneurs. This study identified the recovery factors from the grief of business failures of serial entrepreneurs and analyzed Shepherd's(2003) three areas: loss orientation, restoration orientation, and dual process. To this end, individual in-depth interviews were conducted with 12 small business serial entrepreneurs who challenged re-startup to identify the attributes of recovery factors that were not identified with quantitative data. As a result of the study, first, recovery factors were investigated in three areas: individual orientation, family orientation, and network orientation. It was found to help improve recovery in nine categories: self-esteem, persistence, personal competence, hobbies, self-confidence, family support, networks, religion, and social support. Second, recovery obstacle factors were investigated in three areas: psychological, economic, and environmental factors. Nine categories including family, health, social network, business partner, competitor, partner, fund, external environment, and government policy were found to persist negative emotions. Third, the emotional processing process for grief was investigated in three areas: loss orientation, restoration orientation, and dual process. Ten categories such as family, partner support, social member support, government support, hobbies, networks, change of business field, moving, third-party perspective, and meditation were confirmed to enhance rapid recovery in the emotional processing process for grief. The implications of this study are as follows. The process of recovering from the grief caused by business failures of serial entrepreneurs was attempted by a qualitative study. By extending the theory of Shepherd(2003), This study can be applied to help with recovery research. In addition, conceptual models and propositions for future empirical research were presented, which can be discussed in carious academic ways.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.418-428
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• 2022

The purpose of this study was to obtain the codex classification information on the primary food commodity (fresh state) of processed foods of plant origin that are included in the Codex Classification of Foods and Animal Feeds. Furthermore, whether or not the primary food commodity is included in the primary food classification from the Food Code of Korea was investigated. The results are summarized as follows: First, the Codex Classification information (number of classification codes/number of the primary food commodity group that fresh commodities of processed foods are classified/number of primary food commodity that is not included in the Codex Classification) by a processed food group appeared to be 46/8/0 for dried fruits, 76/11/1 for dried vegetables, 54/4/12 for dried herbs, 36/1/0 for cereal grain milling fractions, 17/4/3 for oils and fats (crude), 34/8/9 for oils and fats (refined), 20/8/0 for fruit juices, 3/2/0 for vegetable juices, and 19 codes for teas (in the Codex Classification, the primary food commodity group for tea does not exist). Second, the number of the primary food commodities not included in the Food Code of Korea was 9 for dried fruits, 14 for dried vegetables, 35 for dried herbs, 0 for cereal grain milling fractions, 6 for teas, 3 for oils and fats (crude), 9 for oils and fats (refined), 2 for fruit juices, and 0 for vegetable juices. Third, it was demonstrated that caution should be exercised when using Codex Classification due to differences in food classification between Codex and Korea, such as coconut (Codex, as tree nut as well as assorted tropical and sub-tropical fruit) and olive (Codex, as assorted tropical and sub-tropical fruit as well as olives for oil production), as well as special cases in the Codex Classification, such as dried chili pepper (Codex, as spice), tomato juice (Codex, as vegetable for primary food commodity and as fruit juice for juice) and ginger (Codex, as spice for rhizome and not including as primary commodity for leaves).

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.347-355
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• 2022

The safety valve (PSV) is a safety device that automatically releases a spring when the pressure generated by various causes reaches the set pressure, and is restored to a normal state when the pressure falls below a certain level. Periodic inspection and monitoring of safety valves are essential so that they can operate normally in abnormal conditions such as pressure rise. However, as the current safety inspection is performed only at a set period, it is difficult to ensure the safety of normal operation. Therefore, evaluation items were developed by finding failure modes and causative factors of safety valves required for safety management. In addition, it is intended to provide decision-making information for securing safety by deriving the priority of items. To this end, a Delphi survey was conducted three times to derive evaluation factors that were judged to be important in relation to the Failure Mode Cause Factor (FMCFs) of the safety valve (PSV) targeting 15 experts. As a result, 6 failure modes of the safety valve and 22 evaluation factors of its sub-factors were selected. In order to analyze the priorities of the evaluation factors selected in this way, the hierarchical structure was schematized, and the hierarchical decision-making method (AHP) was applied to the priority calculation. As a result of the analysis, the failure mode priorities of FMCFs were 'Leakage' (0.226), 'Fail to open' (0.201), 'Fail to relieve req'd capacity' (0.152), 'Open above set pressure' (0.149), 'Spuriously' 'open' (0.146) and 'Stuck open' (0.127) were confirmed in the order. The lower priority of FMCFs is 'PSV component rupture' (0.109), 'Fail to PSV size calculation' (0.068), 'PSV Spring aging' (0.065), 'Erratic opening' (0.059), 'Damage caused by improper installation and handling' (0.058), 'Fail to spring' (0.053), etc. were checked in the order. It is expected that through efficient management of FMCFs that have been prioritized, it will be possible to identify vulnerabilities of safety valves and contribute to improving safety.

• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.371-381
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• 2022

This study causally investigates whether high school student with high science learning motivation becomes to achieve more or vice versa, and also how those two factors affect STEM career motivation. Research participants were 1st year students in a high school at Seoul. We surveyed their science learning motivation three times in the same time interval in the fall semester of 2021, and once a STEM career motivation in the third period. We collected data from 171 students with their mid-term and final exam scores, with which, we constructed and fitted an autoregressive cross-lagged model. The research model shows high measurement stability and fit indices. All the autoregressive and cross-lagged paths were statistically significant. However, standardized regression coefficients were larger in path from motivation to achievement compared to the opposite. Only science learning motivation shows significant direct effect on STEM career motivation, rather than achievement. For indirect effects, the first science learning motivation affected the final exam score and STEM career motivation, and the final exam score affected STEM career motivation. However, the final exam score did not have a total effect toward STEM career motivation. The result of this study shows reciprocal and cyclic causality between science learning motivation and achievement - in comparison, the effect of motivation for the opposite is larger than that of achievement. Also the result of this study strongly reaffirms the importance of science learning motivation. Instructional implications for strengthening science learning motivation throughout a semester was discussed, and a study for the longitudinal effect of science learning motivation and achievement in high school student toward future STEM vocational life was suggested.

• Science of Emotion and Sensibility
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• v.25 no.1
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• pp.3-20
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• 2022

Recently, prior to the commercialization of urban air mobility (UAM), the importance of R&D for air transportation-related industries in urban areas has significantly increased. To create a UAM environment, research is being conducted on personal air vehicles (PAVs). They are key means of air transportation, but research on the physical factors influencing their passengers is relatively insufficient. In particular, because the PAV is expected to be used as a living space for the passengers, research on the effects of the physical elements generated in the PAV on the human body is essential to design an interior space that supports the in-vehicle activities of the passengers. Therefore, the purpose of this study is to derive the constraint factors that affect the human body due to the air navigation characteristics of the PAV and to understand the impact of these constraint factors on the bodies of the passengers performing in-vehicle activities. The results of this study indicate that when the PAV was operated at less than 4,000 ft, which is the operating standard, the constraint factors were noise, vibration, and motion sickness caused by low-frequency motion. These constraint factors affect in-vehicle activity; thus, the in-vehicle activities that can be performed in a PAV were derived using autonomous cars, airplanes, and PAV concept cases. Furthermore, considering the impact of the constraint factors and their levels on the human body, recommended constraint factor criteria to support in-vehicle activities were established. To reduce the level of impact of the constraint factors on the human body and to support in-vehicle activity, the seat's shape and built-in functions of the seat (vibration reduction function, temperature control, LED lighting, etc.) and external noise reduction using a directional speaker for each individual seat were recommended. Moreover, it was suggested that interior materials for noise and vibration reduction should be used in the design of the interior space. The contributions of this study are the determination of the constraint factors affecting the in-vehicle PAV activity and the confirmation of the level of impact of the factors on the human body; in the future, these findings can be used as basic data for suitable PAV interior design.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.1
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• pp.53-67
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• 2022

This study started from recognizing the need to study place identity from the perspective of residents experiencing the place in daily life. The subject area of the study, Shin-Cheorwon, Galmal-eup, Cheorwon-gun, Gangwon-do area, had a low population until the division of Korea in 1945. Since then, the residents have created the milieu under Shin-Cheorwon's regional historic and cultural context. Thus, the study on this area can show the formation of the interrelationship of the region and residents. The purpose of this study is to understand the meaning and identity of the everyday places of Shin-Cheorwon. Photovoice was chosen as the method for successful Participatory Research; Participant's active intervention stage, 'Documentation (4th step)', Narration (5th step), researcher's analysis stage 'Ideation (6th step)' were specifically used. As a result, the following characteristic of the places chosen by participants could be found: the meaning and relationship with the residents, similarities, and differences in people shown based on their age, length of residence, etc. Through this, participants recollected the past places, found the meaning of the place of the present, and deduced the placeness that Shin-Cheorwon should have in the future. The study identified the place identity that holds the perspective of the residents in their daily life and provides implications on the follow-up studies of place identity. In addition, it is expected that it will apply to urban planning and spatial design in further studies of how residents perceive the space formed by urban development using photovoice methodology.