• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.143-151
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• 2022

Purpose. The purpose of this study was to evaluate the performance efficiency of two different drill combinations according to the heat generated and drilling time. Materials and methods. In this study, cow ribs were used as research materials. To test the specimen, cow bones were rid of fascia and muscles, and a temperature sensor was mounted around the drilling area. The experimental group was divided into a group using a guide drill and a group using a Lindmann drill according to the drill used before the initial drilling. The drilling sequence of the guide drilling group is as follows; guide drill (ø 2.25), initial drill (ø 2.25), twist drill (ø 2.80), and twist drill (ø 3.20). The drilling sequence of the Lindmann drilling group is as follows; Lindmann drill (ø 2.10), initial drill (ø 2.25), twist drill (ø 2.80), and twist drill (ø 3.20). The temperature was measured after drilling. For statistical analysis, the difference between the groups was analyzed using the Mann-Whitney U test and the Friedman test was used (α = .05). Results. The average performance efficiency for each specimen of guide drilling group ranged from 0.3861 to 1.1385 mm³/s and that of Lindmann drilling group ranged from 0.1700 to 0.4199 mm³/s. The two drill combinations contained a guide drill and Lindmann drill as their first drills. The combination using the guide drill demonstrated excellent performance efficiency when calculated using the drilling time (P < .001). Conclusion. Since the guide drill group showed better performance efficiency than the Lindmann drill group, the use of the guide drill was more suitable for the primary drilling process.

• Journal of the Economic Geographical Society of Korea
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• v.25 no.1
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• pp.109-130
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• 2022

The Vietnamese government has proposed contract farming through a new type of cooperative as an institutional innovation which aims to restructure the agricultural sector. However, policy changes often impact farmers, who bear the primary effects of the transition process. Understanding households' strategies for land use and livelihood is crucial for policymaking in the agricultural development field. This study was conducted in the rural Binh Dao commune in Central Vietnam. We analyzed household members' labor force changes and their livelihood behaviors after their participation in a contract farming scheme using qualitative analysis methods combined with geographic information system (GIS) support, based on secondary data and in-depth interviews of 190 farmers. Simultaneously, we created a digital map of the cooperative's production area to investigate changes in land use and production activities. The findings show that contract farming shaped the vertical coordination of the value chain from the farmers to the cooperative and agricultural product trading companies. Subsequently, it encouraged land use and labor efficiency due to mechanical support. In addition, it also increased productivity and protected farmers from market risks. However, despite its positive effects on agricultural productivity in this case, the contract farming scheme could not achieve the restructuring of the rural labor force toward non-agricultural sectors. Ironically, farmers in the Binh Dao commune tended to increase cultivable land during the agricultural restructuring program, rather than switching their labor forces to non-agricultural sectors. The lack of stable non-farming job opportunities in rural Vietnam results in challenges to the efficiency of agricultural restructuring programs. Consequently, farmers in the Binh Dao commune are still smallholder farmers, depending on the family labor force.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.510-519
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• 2021

The purpose of this study was to investigate the effect of the microbial reduction and quality maintenance of the physical and chemical pretreatment of Allium monanthum. For physical treatment, handwash, bubble wash and ultrasonication were conducted at 50℃ and 60℃ for 1, 3 and 5 minutes, respectively, and for chemical treatment the sample was immersed in fumaric acid and acetic acid of 1.5% and 2% concentrations for 1, 3 and 5 minutes, respectively. As a result of the microorganism and quality analysis, 3 minutes of bubble wash was the most effective physical pretreatment in reducing fungi although the effect on reducing total viable bacterial was small. Furthermore, 5 minutes of ultrasonication at 60℃ significantly reduced microorganisms, but also resulted in the reduction of the a value of chromaticity, which cause the green color to fade. With chemical pretreatment, it was found that treating with fumaric acid was more effective in reducing the total viable bacteria and fungi than acetic acid. The result shows that 1.5% concentration of fumaric acid is the most effective with 3 minutes of treatment time. The quality of Allium monanthum were compared in the combination of the two most effective microorganism reduction pretreatments: 3 minutes of bubble wash (B3) and 3 minutes in 1.5% fumaric acid (F153). As a result of analyzing the quality characteristics over 9 days of storage at 4℃ after the treatments, it was revealed that the BF treatment is more effective in reducing fungi than the total viable bacteria. The results shows that the BF treatment is more effective in reducing total viable bacteria, whereas the F153 treatment is more effective in reducing fungi. Also, it was found that the 𝚫E value in BF was the lowest, whereas F153 treatment showed the green color faded. The maximum cohesiveness changed more significantly in the green stems than in the roots. On the 9th day of storage, the hardness of the green stem was found to be maintained at the highest level (P<0.05) after F153 treatment, whereas that of the roots decreased (P<0.05) since the 6th day after the bubble wash. Considering the reduction of microorganisms and the quality maintenance of Allium monanthum, the most effective pretreatment methods were 3 minutes in 1.5% fumaric acid for reducing microorganisms and maintaining color and maximum cohesiveness, and the combined process could also be effective if the expiration period is within 3 days.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.168-184
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• 2022

This paper examined the construction techniques of the earthen fortifications in the Hanseong Period of Baekje Kingdom, which has been researched most frequently among the Three Kingdoms. The construction processes of the Earthen Fortifications were reviewed and dividing into 'selection of location and construction of the base', 'construction of the wall', and 'finish, extension and repair'. The results show that various techniques were mobilized for building these earthen fortifications. Techniques which were adequate for the topography were utilized for reinforcing the base, and several other techniques were used for constructing the wall. In particular, techniques for wall construction may be clearly divided into those of the fill(盛土) and panchuk(版築) techniques. The fill method has been assumed since the 2000s to have been more efficient than the panchuk technique. This method never uses the structure of the panchuk technique and is characterized by a complex soil layer line, an alternate fill, use of 'earth mound(土堤)'/'clay clod(土塊)', and junctions of oval fill units. The fill method allows us to understand active technological sharing and application among the embankment structures in the period of the Three Kingdoms. The panchuk technique is used to construct a wall using a stamped earthen structure. This technique is divided into types B1 and B2 according to the height, scale, and extension method of the structure. Type B1 precedes B2, which was introduced in the late Hanseong Period. Staring with the Pungnap Earthen Fortification in Seoul, the panchuk technique seems to have spread throughout South Korea. The techniques of the fill and panchuk techniques coexisted at the time when they appeared, but panchuk earthen fortifications gradually dominated. Both techniques have completely different methods for the soil layers, and they have opposite orders of construction. Accordingly, it is assumed that both have different technical systems. The construction techniques of the earthen fortifications began from the Hanseong Period of Baekje Kingdom and were handed down and developed until the Woongjin-Sabi Periods. In the process, it seems that there existed active interactions with other nations. Recently, since studies of the earthen fortifications have been increasing mainly in the southern areas, it is expected that comparative analysis with neighboring countries will be done intensively.

• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.311-324
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• 2022

This study analyzed the types of scientific emoticons made by science-gifted elementary school students and their perceptions on making scientific emoticons. To do this, 71 students from 4th to 6th graders of two gifted science education center in Seoul were selected. Scientific emoticons made by the students were analyzed according to the number and types. Their perceptions on making scientific emoticons were also analyzed through a questionnaire and group interviews. In the analyses for types of text in the scientific emoticons, 'word type' and 'sentence type' were made more than 'question and answer type'. And the majority of students made more 'pun using pronunciation type' and 'mixed type' than other types. They also made more 'graphic type' and 'animation type' than 'text type' in the images of the scientific emoticons. In the analyses for the information of the scientific emoticons, 'positive emotion type' and 'negative emotion type' of scientific emoticons were made evenly. The students made more 'new creation type' than 'partial correction type' and 'entire reconstruction type'. They also used scientific knowledge that preceded the knowledge of science curriculum in their grade level. The scientific knowledge of chemistry was used more than physics, biology, earth science, and combination field. 'Name utilization type' was more than 'characteristic utilization type' and 'principle utilization type'. Students had various positive perceptions in making scientific emoticons such as 'increase of scientific knowledge', 'increase of various higher-order thinking abilities', 'ease of explanation, use, memory, and understanding of scientific knowledge', 'increase of fun, enjoyment, and interest about science and science learning', and 'increase of opportunity to express emotions'. They were also aware of some limitations related to 'difficulties in the process of making scientific emoticons', 'lack of time', and 'limit that it may end just for fun'. Educational implications of these findings are discussed.

• Journal of Korea Entertainment Industry Association
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• v.15 no.1
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• pp.131-142
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• 2021

Purpose: Clinical practicums via non-face-to-face methods were inevitable due to the COVID-19 pandemic. We developed an online program for emergency nursing care and identified the feasibility of the program and the learning achievements of students. Methods: This was a methodological study. The program was developed by three professors who taught theory and clinical practicum for adult nursing care and clinical experts. Students received four hours of video content and two task activities every week in four-week program. Real-time interactive video conferences were included. Qualitative and qualitative data were collected. Results: A total of 96 students participated in the program. The mean score for overall satisfaction with the online program was 4.72(±1.02) out of 6. Subjects that generally had high learning achievement scores were basic life support care, fall prevention, nursing documentation, infection control, and anaphylaxis care. As a result of a content analysis of 77 reflective logs on the advantages of this program, students reported that "experience in applying nursing process," "case-based learning and teaching method," and "No time and space constraints" were the program's best features. Conclusion: Collaboration between hospitals and universities for nursing is more important than ever to develop online content for effective clinical practicum.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.226-240
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• 2022

Local governments over a certain size in Republic of Korea may conduct Environmental Impact Assessment (EIA) considering regional characteristics if it is necessary, in accordance with Article 42 of the 「Environmental Impact Assessment Act」. However, it was investigated that the number of local government EIA operation in many local governments was less than initial expectations. In order to improve it, the status of ordinances and consultation guidelines which are different for each local government need to be compared, and the institutional issues forthe relevant local governments must be found considering regional characteristics. Furthermore, detailed regulation and guidance on the local government EIA procedure should be included in the consultation guidelines and related information need to be provided. In this study, focusing on the case of Incheon Metropolitan City, the status of local government EIA ordinances in metropolitan cities and provinces with a similar condition was investigated, and the types and scope of target projects were compared and analyzed. In addition, consultation guidelines forIncheon Metropolitan City were written, and improvements on the procedure flow and overall schedule designation derived from the process were presented. In the case of Incheon Metropolitan City, there were no detailed information officially announced regarding the regulations of the local government EIA ordinance and follow-up management, so the administrative system of the local government needed to be reinforced in this field. Meanwhile, considering the status of local environment and geography, some target project types were deemed necessary to be added: port construction projects, water resource development projects, railroad construction projects, and military facilities installation projects. The results of this study will provide useful information to local governments which want to improve their operation effectiveness by reorganizing the local government EIA system and preparing specific guidelines.

• Journal of Bio-Environment Control
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• v.31 no.2
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• pp.79-89
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• 2022

With the wide use of greenhouses, the working hours have been increasing inside the greenhouse for workers. In the closed ventilated greenhouse, the internal environment has less affected to external weather during making a suitable temperature for crop growth. Greenhouse workers are exposed to organic dust including soil dust, pollen, pesticide residues, microorganisms during tillage process, soil grading, fertilizing, and harvesting operations. Therefore, the health status and working environment exposed to workers should be considered inside the greenhouse. It is necessary to secure basic data on particulate matter (PM) concentrations in order to set up dust reduction and health safety plans. To understand the PM concentration of working environment in greenhouse, the PM concnentrations were monitored in the cut-rose and Hallabong greenhouses in terms of PM size, working type, and working period. Compare to no-work (move) period, a significant increase in PM concentration was found during tillage operation in Hallabong greenhouse by 4.94 times on TSP (total suspended particle), 2.71 times on PM-10 (particle size of 10 ㎛ or larger), and 1.53 times on PM-2.5, respectively. During pruning operation in cut-rose greenhouse, TSP concentration was 7.4 times higher and PM-10 concentration was 3.2 times higher than during no-work period. As a result of analysis of PM contribution ratio by particle sizes, it was shown that PM-10 constitute the largest percentage. There was a significant difference in the PM concentration between work and no-work periods, and the concentration of PM during work was significant higher (p < 0.001). It was found that workers were generally exposed to a high level of dust concentration from 2.5 ㎛ to 35.15 ㎛ during tillage operation.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.6
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• pp.1-15
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• 2021

This study considered Forest Specialists, who are nurtured by the legal system through the analysis of laws and regulations under the jurisdiction of the Korea Forest Service. In particular, the transition process of forest-related laws and laws to train forest specialists were identified. In addition, changes and characteristics regarding the cultivation of professional forestry talents according to forestry policy were investigated. As a result, it was found that Forest Specialist on policy dealt with forestry success for forestry promotion, and forestry engineers dealt with technical skills for forestry industry development. In addition, according to the revision of the laws for the sustainable use of timber, wood-structural engineers, timber grade evaluators, and timber education specialists are trained separately. Forest Specialists concerned with forest welfare policies were found to train forest experts and complete specialized training courses to provide various services for forest cultural and recreation facilities, healing forests, and forest leisure sports facilities. There is an instructor for forest leisure sports. Forest welfare experts are divided into forest education experts and forest healing instructors; forest education specialists are further divided into forest interpreters, forest guides for children, and forest trekking guides. Forest Specialists on forest protection policy were found to train arboretum and garden experts for the efficient management and exhibition of arboretums. Gardens and tree doctors and tree treatment technicians for arboretums wer also trained. A tree doctor and a tree treatment technician were found to have the necessary qualifications to run a tree hospital business, diagnosing and treating tree damage. Therefore, it is thought that the Korea Forest Service is nurturing Forest Specialists with technical capabilities for forestry promotion, forest industry development, and tree treatment; and the Forest Specialists can provide education and welfare services at culture, recreation, treatment, and conservation sites in forests.

• Journal of Life Science
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• v.32 no.10
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• pp.784-791
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• 2022

This study observed changes in the body composition of Protaetia brevitarsis sinulensis larvae when reared with feed that included noni and nipa palm. Compared to the control group, the death rate and product yield of the treatment group were improved after the larval fasting process. The brightness of the larval powder of the treatment group increased, but the redness decreased. The crude fat content of the treated group was slightly increased according to the assays of the general components, but the mineral content was significantly increased. The total structural amino acids of the treatment group decreased, but the total free amino acids increased. The structural amino acids generally tended to decrease in the treatment group. However, the free amino acids showed no specific differences. Among the free amino acids, tryptophan, phosphoserine, and methylhistidine were highly increased in the treatment group, whereas threonine, methionine, and asparagine showed the opposite results. Among the polyunsaturated fatty acids, eicosapentaenoic acid (C20:5n3) of omega-3 was increased in the treatment group, but the omega-6 series was decreased. Since minerals, total free amino acids, and omega-3 fatty acids in the treatment group were increased compared to the control group, we suggest that noni and nipa palm can potentially be applied to the production of functionally improved substances as additional sources of feed for Protaetia brevitarsis sinulensis larvae.