The research model of panel data analysis in this study was used as the dependent variables and the business characteristics of the welding industry were reflected in the research model for systematic analysis of the effect of welding technology on the welding industry. As a result of the existing research, the domestic welding technology is seriously encroaching on the domestic welding industry between the United States, Japan and China. There is no quantitative statistical analysis on this aspect. In this study, the panel data analysis is used to indicate differences in explanatory power by numerical values of POLS model, fixed effect and random effect. And the prior studies on the current status of welding industry related to arc welding, special welding, multiple welding, welding and bonding technology are applied by the panel data analysis. Therefore, the problems of existing research are diagnosed while presenting the future research directions.

In this study, quality keywords of frequent mention of failures were extracted by analyzing the field operational data of main battle tanks recorded for about 5 years. As a result of the data analysis, the leaf spring assembly of the crew hatches corrosion and failure was frequently occurred. FEA(Finite Element Analysis) and tests were performed to analyze the cause of the failure, and it was confirmed that durability of the leaf spring was insufficient. Therefore a design modification study was conducted to improve durability of the leaf spring, and FEA and durability tests demonstrated the improvement. As a result, the durability of leaf spring was improved at least 3.3 times compared to before improvement. This study will contribute to suggesting the use of data analysis in the defense area and improving the operability of the main battle tanks.

The purpose of this study is an application of Lee’s Menu Engineering (LME) method for menu analysis on the eight kinds of pizza selected from 17 kinds of pizza served by an Italian restaurant near by the Keimyung College University campus. The eliminated nine items were in the third quadrant or below the trend line. The LME method is more efficient than generally used methods such as the Miller, Kasavana & Smith, Uman, Pavesic and Merricks & Jones method. The LME method comprises reference lines and four quadrants created by x, y axes and its average values. The x and y axes comprise the sales ratio (MM%, percentage of the Menu Mix) and the weighted contribution margin (WCM%, percentage of the Weighted Contribution Margin) respectively. The obtained results are such that total sales increased by 1.59% from 58,747,200 won to 59,684,000 won, despite the decrease in sales volume. Total contribution margin also increased from 35,248,320 won to 35,810,400 won. The trend line also shows from y=0.9147x (R2=0.703) to y=0.9944x (R2=0.9893). These results indicate that the LME method is superior in practical applications.

This study investigates the historical development of English education in South Korea regarding the fourth and fifth National Curriculum Period. By analyzing the newspaper articles in five major newspapers in Korea, we focused on the characteristics of English education in each period. The research questions are: 1) what are the characteristics of the fourth National Curriculum? 2) what are the characteristics of the fifth National Curriculum?, and 3) what is the implication of these previous curricula on the current English education in South Korea? During the fourth National Curriculum Period, after the successful hosting of the 1986 Asian Games and the 1988 Summer Olympic Games in Seoul, the importance of communication skills in English spread throughout the country. Accordingly, the need for early English education emerged. In the fifth curriculum, various social factors, including the liberalization of overseas travel, led positive washback effects on English education. In elementary schools, English instructions were conducted as a special activity. In secondary schools, various changes in the educational environment were involved, including the introduction of listening tests and recruitment of native English teachers, which still affects English education in 2020. This paper concludes with educational implications and future research directions.

The purpose of this study was to analyze a cohort, age, and time effects on sodium and sodium-calorie intake using the 2007~2017 Korea National Health and Nutrition Examination Survey (KNHANES). For analysis, we have constructed cohort panel data that combine KNHANES data in a time series. The age effect gradually increased from age 45~49 and then decreased afterwards. The time effect showed an increase in average sodium intake until 2010 followed by a subsequent decrease. The cohort effect showed that the sodium intake was the highest for the War of Liberation 1946~1953, and that the younger the latter, the lower the sodium intake. According to a cohort analysis, the younger the generation, the lower the sodium intake compared to the calorie intake, according to the baby boomers. Based on the results of this study, efforts should be made to educate and promote the dieting and providing low-salt meals to reduce sodium intake by generation. An analysis of the health hazards including sodium by generation and age is thought to enable the establishment relevant policies.

In this paper, we investigate the relationship between control system of Bosch system and that of Delphi system by measuring the high and low voltage waveform, current waveform and fuel injection quantity of D-2 and R- engines. Waveform measurements are used the PICO scope and the CDS tester. The injectors of D-2 and R-engines were tested under no load condition using injector with normal fuel injection quantity, injector with small fuel injection quantity and injector with many fuel injection quantity. The relation between current energy and fuel injection quantity shows that the injector variation rate of D2-engine is much larger than that of R-engine. The injector current energy of the D2-engine was more linear than that of the R-engine, therefore making the system more stable. Although the control system of the D2-engine is a more stable system only in terms of the durability of the internal parts of the injector, the injector of the R-engine has a good response because the current value is large.

The purpose of this study was to provide the basic data of butternut squash (Cucurbita moschata) according to the drying methods. The proximate composition and chromaticity of freeze-dried and hot air-dried Cucurbita moschata powders were evaluated, and the antioxidant effects of these ethanolic extracts were analyzed by DPPH, ABTS, FRAP, reducing power activity, total phenolic, and flavonoid content. As a result, Cucurbita moschata was revealed to have high carbohydrate and crude protein contents, while crude ash and crude fat contents were relatively low. Also, it was confirmed that the hot air-dried Cucurbita moschata had lower L, a, and b values than the freeze-dried Cucurbita moschata. Additionally, as a result of analyzing the antioxidant activity of Cucurbita moschata ethanolic extracts, hot air-dried Cucurbita moschata ethanolic extract showed significantly superior antioxidant activity than freeze-dried Cucurbita moschata ethanolic extract. Also, hot air-dried Cucurbita moschata ethanolic extract was revealed to have a higher polyphenol content, but slightly lower flavonoid content than freeze-dried Cucurbita moschata ethanolic extract. Based on the data from this study, further experiments on Cucurbita moschata material are necessary.

This study aims to classify parents by considering important factors in the management of foodservice for children. An offline survey was conducted by enrolling 583 Korean parents whose children attended public or private kindergartens in Seoul. The important factors required for managing foodservice for children are meal service resources, menu management, and food allergy. Considering these factors, parents were grouped into 3 clusters: the allergy important group, environment important group, and high concern group. Evaluation of the demographic characteristics revealed a significant difference between clusters with respect to type of kindergarten. Parents perceived that a private kitchen is more required than a private dining room, and perceptions about the need for a private kitchen and dining room were significantly different among the clusters. Furthermore, the results reveal significant differences between clusters, when considering the need to support meal service. Therefore, the government needs to consider characteristics of the parent cluster if they plan to support the kindergarten foodservice. We believe that this study can be used as supportive data to establish a working policy.

The diversity and characterization of microorganisms isolated from the soil around several ranches in Korea were confirmed in this study. To isolate halophilic microorganisms, the marine agar medium was basically used and cultivated at 37℃ for several days. After single colony isolation, a total of 116 pure colonies were isolated and phylogenetic analysis was carried out based on the result of 16S rDNA sequencing, indicating that isolated strains were divided into 4 phyla, 23 families, 30 genera and 51 species. To confirm whether isolated strain can be a candidate for the fermentation of diverse food ingredients, amylase, lipase, and protease enzyme assays were performed individually, showing that 92 strains possessed at least one enzyme activity. Especially 4 strains, identified to Jonesia quinghaiensis (isolate name: JSF 19-2), Halomonas alkaliantarctica (isolate name: JSF 21), Bacillus velezensis (isolate name: NWFY-36), and Staphylococcus capitis subsp. urealyticus (isolate name: MSY-5), showed all enzyme activity tested. Moreover, 17 strains showed the ability for auxin production. This result indicated that isolated strains have shown the possibility of the application for the food and feed industries. Therefore, this study has contributed to securing domestic biological resources and the improvement of hydrolytic enzyme activity by using isolated strains.

This study examined how teaching and learning activities in primary English textbooks include the components of creativity and character building. Three third and fourth grade level textbooks based on the 2015 revised curriculum were analyzed in order to find the proportions of the components of creativity and character building, and the types of learning activities that embody those components were analyzed by examining the teachers’ guides. The analysis revealed that all of the textbooks examined included diverse components that were intented to increase creativity, among which components stimulating divergent thinking and originality were a high proportion, while convergent thinking and dispositional aspects appeared less frequently. Among character building components, care-forgiveness and responsibility were two of the more popular components, while honesty and moral judgment were few and far between. From these findings, this study suggests that the components of creativity and character building should be more evenly distributed across textbook activities since they should be of equal importance in education.

The objective of this study was to review and evaluate the growing subject of food tourism research, and thus identify the trend of food tourism research. Using a Text mining technique, this paper discovered the trends of the literature on food tourism that was published from 2004 to 2018. The study reviewed 201 articles that include the words ‘food’ and ‘tourism’ in their abstracts in the KCI database. The Wordscloud analysis results presented that the research subjects were predominantly ‘Festival’, ‘Region’, ‘Culture’, ‘Tourist’, but there was a slight difference in frequency according to the time period. Based on the main path analysis, we extracted the meaningful paths between the cited references published domestically, resulting in a total of 12 networks from 2004 to 2018. The Text network analysis indicated that the words with high centrality showed similarities and differences in the food tourism literature according to the time period, displaying them in a sociogram, a visualization tool. This study has implications that it offers a new perspective of comprehending the overall flow of relevant research.

This research confirmed the diversity and characterization of halophilic microorganisms isolated from the various solar salterns, collected on the inside and outside of the country. To isolate strains, the marine agar medium was basically used and cultivated at 37oC for several days aerobically. After single colony isolation, a totally of 230 pure colonies were isolated and phylogenetic analysis was carried out based on the result of 16S rDNA sequencing, indicating that isolated strains were divided into 4 phyla, 12 families, 27 genera and 64 species. Firmicutes phylum, the main phyletic group, comprised 89.6% with 3 families, 17 genera and 52 species of Bacillaceae, Staphylococcaceae and Carnobacteriaceae. To confirm whether isolated strain can produce industrially useful enzyme or not, amylase, lipase, and protease enzyme assays were performed individually, showing that 177 strains possessed at least one enzyme activity. Especially 17 strains showed all enzyme activity tested. This result indicated that isolated strains have shown the possibility of the industrial application. Therefore, this study has contributed to securing domestic genetic resources and the expansion of scientific knowledge of the halophilic microorganisms community in solar salterns.

중국의 유망한 성장산업으로 들 수 있는 것이 화장품산업이다. 중국 화장품산업과 관련한 국내외 연구를 요약 하면, 크게 두 가지 흐름으로 나눌 수 있다. 첫째는 중국 화장품산업의 진출전략 또는 수출전략에 관한 연구이다. 대부분의 국내 연구가 여기에 해당한다. 둘째는 중국화장품 산업의 전망을 분석하고, 경영전략의 차원에서 미래 성장전략을 제시하는 연구이다. 본 연구는 두 번째 연구흐름과 관련이 있다. 즉, 중국 화장품 산업에 속하는 주요 기업의 전략유형을 인지적 관점에서 파악하고자 한다. 본 연구의 목적을 구체적으로 요약하면 다음과 같다. 첫째, 전략집단 분류의 동일성을 검증하는 것이다. 이는 기존 연구에서 중국의 화장품 기업을 대상으로 분류한 전략집단의 유형과 동일한 유형의 전략집단이 본 연구를 통해서도 분류되는지를 검증하는 것이다. 만약 기존 연구와 본 연구가 독립적으로 분류한 전략집단의 유형이 동 일하게 나온다면, 두 연구의 타당성은 높아질 것이다. 둘째, 전략집단 소속의 일관성을 검증하는 것이다. 이는 전 략집단 분류의 동일성이 달성될 경우, 각 전략집단에 소속되는 기업들도 일관되게 분류되는지를 검증하는 것이다. 본 연구는 이상의 두 가지 연구목적을 달성하기 위해, 중국 화장품 산업에 속하는 50개 기업을 대상으로 최고 경영층 인지적 특성을 설문조사를 통해 측정하였다. 이를 바탕으로 전략집단을 분류하고, 그 결과를 기존 연구 (량최정․방호열, 2019)와 비교함으로써 전략집단 분류의 동일성(첫 번째 연구목적)과 전략집단 소속의 일관성 (두 번째 연구목적)을 검증하였다. 실증분석 결과를 보면, 중국 화장품 기업의 전략유형에 있어서, 기존 연구와 본 연구가 분류한 유형이 유사하 게 나타났으며, 전략집단의 소속도 일관성을 보이는 것으로 나타났다. 결과적으로 전략집단 분류의 동일성과 전 략집단 소속의 일관성이 검증되었다. 이러한 연구결과는 중국의 화장품 산업을 이해하고 효과적인 전략을 수립하 는데 유용한 도움이 될 것이다. 또한 전략집단과 관련한 개념과 이론이 중국과 같은 신흥국 시장에도 적용가능하 다는 것을 알 수 있다.

본 연구는 ABTS radical 소거 활성을 통한 항산화 활성, RAW 264.7 대식 세포에서의 세포 독성, DCF-DA assay을 통한 세포 내 ROS 생성 억제 효과, 항균력을 측정하여 구아바 잎 추출물이 화장품 소재로써의 활용 가능성을 검토하고자 하였다. 실험 결과, 구아바 잎 추출물의 우수한 ABTS radical 소거능을 확인하였다. RAW 264.7 대식세포에서의 세포 독성은 나타나지 않았으며 세포 내에서 ROS 생성량 은 농도 의존적으로 감소하는 억제효과를 확인하였다. 또한 구아바 잎 추출물의 항균력 분석에서는 피부상 재균인 S. aureus, E. coli, C. albicans, P. acnes 균주들에서 항균 활성이 확인되었으며, 각 균주에 대한 최소 저해 농도(MIC)는 대체로 0.25 - 1 mg/mL의 수준으로서 P. acnes ≃ S. aureus < E. coli < C. albican 순의 낮은 농도로 측정되었다. 이와 같은 결과를 통해 구아바 잎 추출물의 항산화 활성과 세포 내 ROS 생성 억제 효과, 피부에 염증을 유발하는 피부상재균에 대한 항균력이 확인됨에 따라 독성이나 부작 용이 없는 기능성 화장품 소재로써의 활용이 가능할 것으로 사료된다.

Due to global climate change, Korea is experiencing flooding and drought severely. It is hard to manage water resources because intensive precipitation during short periods and drought are commonly occurred in Korea, recently. Severe drought occurred in 2015 and 2017 in the islands, and coastal and inland areas in Korea, and the citizens experienced decreased water supply and emergency water service by using bottled water. Therefore, the Korean government provided additional governmental funds such as the grant of drought disaster. In this study, we tried to calculate the cost of water for drought response based on the cost of tap water for the regional local governments in Korea and the grant of drought disaster by the Ministry of the Interior and Safety in Korea, etc. The estimated costs of water for drought responses in coastal and inland areas which have a chance to apply alternative water sources such as brackish or seawater desalination and water reuse in Korea were higher than in other areas in Korea. Additionally, as the novel approach of drought response, the 300 m3/day-scale desalination vessel was suggested to provide desalinated water for the islands in Korea. The estimated expenses of water supply for the target island areas (Sinan-gun and Jindo-gun) by the desalination vessel was lower than those by emergency water service by using bottled water.

본 연구는 부모-자녀 관련 코칭 연구의 동향을 조사하여, 연도별 경향과 연구대상, 연구대상자 수, 연구주제, 연구방법, 학위논문과 학술지 경향을 분석함으로써 향후 부모-자녀 코칭 연구에 대한 구체적인 연구방법과 주제 등 연구방향을 설정하는데 기초자료로 활용할 수 있도록 하는데 목적이 있다. 이를 위해 2005년부터 2019년까지 국내에서 발간된 학술지와 학위논문 중 부모-자녀 코칭 관련 논문 129편을 대상으로 분석하였으며, 연구결과는 다음과 같다. 첫째, 부모-자녀 코칭연구는 2009년 이후 관련 논문 편수가 매해 꾸준히 증가하는 경향을 보이며, 2016년(22편)에 가장 많았으며, 둘째, 연구대상자로 어머니만을 선정한 경우가 60편 (46.5%)으로 가장 많았으며, 연구대상자 수의 경우 50명 미만에서 부모가 84편으로 가장 높게 나타났다. 셋째, 코칭 연구의 대부분이 실험을 통한 효과검증을 한 연구로 129편 중 111편으로 나타났다. 넷째, 연구주제 경향은 코칭과 양육효능감 및 의사소통이 36편(28.0%)으로 가장 높게 나타났다. 다섯째, 연구방법의 경우 양적연구가 76편(58.9%)으로 가장 많았으며, 다음으로 프로그램개발 23편(17.8%)으로 나타났다. 마지막으로 학위논문의 경우 석사 논문이 65편, 박사 학위 논문이 14편으로 나타났다. 학술지의 경우 ‘코칭연구’가 9편으로 가장 많았다. 위 연구결과를 토대로 연구주제, 연구대상, 연구방법의 다양화에 대한 향후 연구방향을 제안하였다.

Even though sewers have been conventionally designed to prevent from sediment deposition using a specified minimum velocity or shear stress at a particular depth of flow or with a particular frequency of occurrence, it was appreciated that these methods do not consider the characteristics and concentration of the sediment and the specific hydraulic conditions of the sewer with sediment. In this study, a densimetric Froude number formula was suggested considering particle diameter and volumetric concentration of the sediment as well as flow depth and flowrate, based on several domestic field inspections, which was compared with other formulas proposed by previous investigators. When the sediment concentration was not considered, the calibration coefficient of 0.125-1.5 to the densimetric Froude numbers of this study was needed to obtain the similar ones with previous investigators’. For the densimetric Froude number formula obtained with consideration of sediment concentration, the exponent value of term Cv was almost the same as that of previous results and that of d50/Rh was similar for Fr < 2.2.

Numerical analysis has been carried out to analyze seawater flow field and power generation characteristics of the tidal current power generation system for various multi channel shroud systems. Geometrical multi channel arrangement largely affects the flow field characteristics in the shroud system which power generation performance through turbine blade depends on. Sectional averaged velocity in front of the turbine blade which increases more than 2 times compared with channel inlet is much influenced as well as the flow from the rear with curl. And flow variation results in high inlet velocity in horizontal arrangements of multi channels with mechanical output of the turbine. These results are expected to be used as applicable data for the development of the tidal power generation system with shrouds.

중국산과 국내산 홍삼 농축액의 혼합비율에 따는 원산지 판별 가능성을 검토하기 위해 전자코를 이용하여 향기 패턴을 분석하였다. 중국산 홍삼 농축액과 국내산 홍삼 농축액의 원산지 판별이 가능하였고 중국산 홍삼농축액의 혼합비율이 증가할수록 검출되어지는 향기 성분의 패턴은 감소하는 경향을 나타내었다. Frequency pattern, derivative pattern을 Vapor printTM 으로 도형화 하여 비교한 결과 서로 다 른 패턴을 보여주어 중국산 홍삼 농축액 첨가비율에 따른 차이는 물론 원산지의 차이도 뚜렷하게 나타났다.

최근 건설기술발전은 시공순서 세분화와 단면강성증진과 같은 기술변화로 선형조건 및 시공여건에 따라 요구되고 있는 다양한 교량 상부거더 형식이 개발되고 있다. 즉, 교량하부 형하공간이 부족한 곳에 설치하여야 하는 저형고 또는 장경간 거더와 같이 각각의 교량 설치 위치 상황에 따라 다른 형식을 요구되고 있다. 이러한 요구로 기존의 하로판형교를 개선한 아치 엣지보로 보강된 U형 강합성 교량을 연구대상 교량으로 선정하게 되었다. 따라서 본 연구는 아치 형태로 변화는 I형 강재의 상부 압축부에 고강도 콘크리트를 충전시켜 각각의 주거더를 구성시킨 하로교형식의 강합성 U형거더를 실물제작하여 구조거동을 분석하였다. 실험하중은 2단계로 구분하여 적용하였다. 1단계는 설계하중 1,200kN의 2.5배인 1차 실험하중 3,000kN을 재하하여 실험오차와 재료비선형성을 확인하였다. 2단계 실험하중 2,000kN에서는 선형분포를 나타냈고 하중제거상태에서 잔류변형이 발생하지 않았다. 분석결과, 아치단면으로 변하는 주거더와 주거더 상단의 충전콘크리트의 합성은 단부의 압축력 집중현상과 같은 아칭효과를 나타냈다.