• 한국미생물·생명공학회지
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• 제32권2호
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• pp.123-127
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• 2004

토양으로부터 oleic acid 를 탄소원으로 이용하여 MCL-PHA의 생산능이 우수한 균주를 분리하여 Pseudomonas sp. MBEL21이라 명명하였다. Pseudomonas sp. MBEL21의 PHA함량을 증가시키기 위하여 여러 가지 필수 영양분의 제한 조건에서 배양한 결과, 인산이 제한된 조건에서 가장 높은 함량의 PHA를 축적하였다. 고농도의 MCL-PHA생산을 위한 Pseudomonas sp. MBEL21의 유가식 배양 전략을 개발하여 28.1 wt％의 함량으로 23 g/L. MCL-PHA를 생산하였다. 또한, 분리된 Pseudomonas sp. MBEL21을 olive oil을 탄소원으로 이용하여 배양한 결과 9.3 wt％의 PHA가 축적되어졌으며, MCL-hydroxyalkanoate와 함께 3-hyoxy-butyrate 의 단량체들로 이루어진 PHA가 확인되어졌다. 이러한 결과들은 분리된 신규 Pseudomonas sp. MBEL21이 저가의 olive oil로부터 생분해성 탄성체의 응용분야를 갖는 MCL-PHA를 효율적으로 생산할 수 있다는 것을 보여준다.

• Journal of Nutrition and Health
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• 제52권6호
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• pp.593-603
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• 2019

Purpose: Previous studies have highlighted that the nutritional behaviors among South Korean workers are far from ideal. This study examined the organizational influences affecting the eating practices of office workers in South Korea. Methods: We conducted in-depth interviews with 22 office workers at 12 companies in South Korea. The interviewer inquired about the employees' daily routines on food and beverage intake. The various factors that influence their food choices in their work environments were also explored. The interviews were transcribed and then analyzed using a content analysis. Results: A framework analysis revealed 7 key recurring themes, and these were grouped under three levels: team-, company-, and corporate group-levels. First, team dinners are core social events for all the workers and they tend to include high-caloric food and alcoholic beverages. The frequency of team meals and the food associated with them depend on various team characteristics such as gender composition, the nature of a team's work and the team leaders' emphasis on group meals. Second, the company's policies and practices regarding budget allocation for team meals and subsidies for cafeteria meals affect the workers' food intake practices. In addition, the physical environment of the worksite cafeterias can influence the choices of foods. Third, various corporate group policies that were not designed to target food intake had additional positive effects on the workers' eating behaviors. Conclusion: This study provides important insights into the broader organizational influences on the food consumption of employees in their workplace. These insights can be used to design and implement more effective intervention strategies for improving the nutritional behaviors of office workers.

• 농업생명과학연구
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• 제45권1호
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• pp.33-40
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• 2011

An efficient method for the rapid micropropagation of Camptotheca acuminata from axillary buds was established by application of various plant growth regulators. Among various cytokinins, $0.5mg\;L^{-1}$ BA showed the best performance on shoot multiplication, number average multiple shoots up to 10.8. The propagated shoot cuttings in vitro were elongated on NN basal medium without plant growth regulators. The secondary multiple shoots were induced at the site of initially induced buds. Rooting was induced directly near the base of the shoot on half-strength NN medium containing $0.5mg\;L^{-1}$ of IBA, whereas high concentration of $1.0mgL^{-1}$ IBA could induce callus at the base of the shoot. The camptothecin content, anticancer compound of the micropropagated plants was contained in various tissues. Camptothecin contents were 1.8 and $2.5mg\;g^{-1}$ dry weight in stems from propagated in vitro and mother plant, respectively. This result may be used to develop strategies for large-scale propagation of elite C. acuminata trees.

• 대한간호학회지
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• 제49권5호
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• pp.526-537
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• 2019

Purpose: The aim of this study was to evaluate the validity and reliability of the Korean version of the Clinical Teaching Behavior Inventory (CTBI). Methods: The English CTBI-23 was translated into Korean with forward and backward translation. Survey data were collected from 280 nurses' preceptors at five acute-care hospitals in Korea. Content validity, construct validity, and criterion-related validity were evaluated. Cronbach's ${\alpha}$ was used to assess reliability. SPSS 24.0 and AMOS 22.0 software was used for data analysis. Results: The CTBI Korean version consists of 22 items in six domains, including being committed to teaching, building a learning atmosphere, using appropriate teaching strategies, guiding inter-professional communication, providing feedback and evaluation, and showing concern and support. One of the items in the CTBI was excluded with a standardized factor loading of less than .05. The confirmatory factor analysis supported good fit and reliable scores for the Korean version of the CTBI model. A six-factor structure was validated ($x^2=366.30$, p<.001, CMIN/df=2.0, RMSEA=.06, RMR=.03, SRMR=.05, GFI=.90, IFI=.94, TLI=.92, CFI=.94). The criterion validity of the core competency evaluation tool for preceptors was .77 (p<.001). The Cronbach's ${\alpha}$ for the overall scale was .93, and the six subscales ranged from .72 to .85. Conclusion: The Korean version CTBI-22 is a valid and reliable instrument for identifying the clinical teaching behaviors of preceptors in Korea. The CTBI-22 also could be used as a guide for the effective teaching behavior of preceptors, which can help new nurses adapt to the practicalities of nursing.

• Smart Structures and Systems
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• 제7권4호
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• pp.241-262
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• 2011

Cast iron pipe has been used as a water distribution technology in North America since the early nineteenth century. The first cast iron pipes were made of grey cast iron which was succeeded by ductile iron as a pipe material in the 1940s. These different iron alloys have significantly different microstructures which give rise to distinct mechanical properties. Insight into the non-destructive structural condition assessment of aging pipes can be advantageous in developing mitigation strategies for pipe failures. This paper examines the relationship between the small-strain and large-strain properties of exhumed cast iron water pipes. Nondestructive and destructive testing programs were performed on eight pipes varying in age from 40 to 130 years. The experimental program included microstructure evaluation and ultrasonic, tensile, and flexural testing. New applications of frequency domain analysis techniques including Fourier and wavelet transforms of ultrasonic pulse velocity measurements are presented. A low correlation between wave propagation and large-strain measurements was observed. However, the wave velocities were consistently different between ductile and grey cast iron pipes (14% to 18% difference); the ductile iron pipes showed the smaller variation in wave velocities. Thus, the variation of elastic properties for ductile iron was not enough to define a linear correlation because all the measurements were practically concentrated in single cluster of points. The cross-sectional areas of the specimens tested varied as a result of minor manufacturing defects and levels of corrosion. These variations affect the large strain testing results; but, surface defects have limited effect on wave velocities and may also contribute to the low correlations observed. Lamb waves are typically not considered in the evaluation of ultrasonic pulse velocity. However, Lamb waves were found to contribute significantly to the frequency content of the ultrasonic signals possibly resulting in the poor correlations observed. Therefore, correlations between wave velocities and large strain properties obtained using specimens manufactured in the laboratory must be used with caution in the condition assessment of aged water pipes especially for grey cast iron pipes.

• 디지털융복합연구
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• 제19권10호
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• pp.303-317
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• 2021

본 연구는 OTT 산업에 특화된 분석틀을 개발하여 OTT 사업자들의 경쟁력 분석을 하는 데에 목적이 있다. 비즈니스 모델, 플랫폼 비즈니스 모델, OTT 특성에 관한 기존연구를 바탕으로 OTT 플랫폼 비즈니스 모델 프레임워크를 개발하였고 관련 자료, 문헌, 내부자료의 데이터를 토대로 사례 분석을 하여 국내 OTT 사업자들이 나아가야 할 방향을 제시하였다. 연구 결과, 국내 OTT 사업자들은 발전된 AI와 빅데이터 기술을 활용해 오리지널 콘텐츠를 제작하고 플랫폼의 인프라 및 서비스의 질을 향상해야 한다. 또한, 보유한 콘텐츠를 맞춤화된 추천 시스템을 통해 충분히 활용할 수 있어야 하고 이용자들이 선호할 해당 플랫폼만의 오리지널 콘텐츠에 아낌없는 투자가 지속되어야 한다. 본 연구는 급변하는 미디어 산업 속에서 OTT 사업자들이 자신만의 경쟁전략을 수립할 수 있는 분석틀을 제공하고 사례 적용을 통해 국내 OTT 사업자들이 나아가야 할 방향성을 제시했다는 점에서 의의가 있다.

• 디지털융복합연구
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• 제19권10호
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• pp.521-533
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• 2021

본 연구의 목적은 온라인 학습 환경에서 간호대학생의 자기주도적 학습 경험을 탐색하는 것이다. 자료 수집은 2021년 7월부터 8월까지 3개의 포커스 그룹 인터뷰를 통해 이루어졌으며, 연구 대상자는 온라인 수업을 경험한 간호대학생 15명이었다. 분석을 위해 모든 면담은 녹음하고 참여자가 말한 그대로 필사하였으며, 질적 내용분석을 이용해 분석하였다. 연구결과 4개의 범주와 11개의 하위범주가 도출되었다. 간호대학생의 자기주도적 학습 경험의 4개 범주는 '학습동기의 인지적 작용', '성찰을 통한 나만의 학습전략 마련', '학습을 지원하는 환경 조성', '교수자의 효과적인 온라인 수업설계와 열의'로 나타났다. 본 연구결과는 온라인 수업 환경에서 간호대학생의 자기주도적 학습전략 마련을 위한 기초자료로 활용될 수 있을 것이다.

• 한국콘텐츠학회논문지
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• 제21권9호
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• pp.24-33
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• 2021

본 연구는 대구·경북지역 대학 총장 인사말에 나타난 의미론적 관계와 대학의 방향성을 탐색하였다. 2020년 9월 기준, 각 대학 웹사이트에서 인사말을 수집하였다. 분석 결과, 머리말엔 긍정적인 인상의 '여러분', '환영하다', '방문하다' 등이 자주 사용되었고 본문엔 '대학'과 '교육'이 주요 단어 쌍을 이뤘다. 연결망 중심성 분석에는 '세계'와 '글로벌'이 높은 값을 보였다. 텍스트 내에 존재하는 의미 구조의 하위 차원을 찾기 위해 군집 분석을 실시한 결과, 중심 집단 3개와 보조 집단 3개가 나타났다. 핵심 군집엔 대학의 사회적 책임과 지역발전, 그리고 세계화를 의미하는 단어들이, 보조 군집엔 사업, 꿈, 인사와 관련한 단어들이 출현하였다. 전문대학과 4년제를 비교하면 전문대학은 산업과 기술적 역량에, 4년제는 교육 역량과 학문적 연구 성과에 중점을 뒀다. 본 연구는 학령인구 감소와 변화하는 사회적 환경 속, 대구·경북 대학들이 내세우는 지향점을 파악한다는 점에서 가치를 가진다.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1045-1059
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• 2021

Various abiotic stressors like drought, salinity, temperature, and heavy metals are major environmental stresses that affect agricultural productivity and crop yields all over the world. Continuous changes in climatic conditions put selective pressure on the microbial ecosystem to produce exopolysaccharides. Apart from soil aggregation, exopolysaccharide (EPS) production also helps in increasing water permeability, nutrient uptake by roots, soil stability, soil fertility, plant biomass, chlorophyll content, root and shoot length, and surface area of leaves while also helping maintain metabolic and physiological activities during drought stress. EPS-producing microbes can impart salt tolerance to plants by binding to sodium ions in the soil and preventing these ions from reaching the stem, thereby decreasing sodium absorption from the soil and increasing nutrient uptake by the roots. Biofilm formation in high-salinity soils increases cell viability, enhances soil fertility, and promotes plant growth and development. The third environmental stressor is presence of heavy metals in the soil due to improper industrial waste disposal practices that are toxic for plants. EPS production by soil bacteria can result in the biomineralization of metal ions, thereby imparting metal stress tolerance to plants. Finally, high temperatures can also affect agricultural productivity by decreasing plant metabolism, seedling growth, and seed germination. The present review discusses the role of exopolysaccharide-producing plant growth-promoting bacteria in modulating plant growth and development in plants and alleviating extreme abiotic stress condition. The review suggests exploring the potential of EPS-producing bacteria for multiple abiotic stress management strategies.

• Journal of Korea Trade
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• 제23권6호
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• pp.14-32
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• 2019

Purpose - This study is designed to provide new insights on trade claim management by typifying trade claims from a relational perspective, which defines trade as an organic combination that exchanges relationships based on a mutual goal instead of conflicts between obligations and rights of the contracting parties. Design/methodology - This is a phenomenological study that aims to typify trade claims based on a relational perspective and extract implications for trade claim management. The research procedures of this study are as follows. First, international commercial dispute cases applying the CISG are collected. Second, the cases collected are quantified through content analysis. The variables for quantification are developed based on a relationship perspective. Third, cluster analysis is conducted on coded data to typify cases. And finally, this study compares the characteristics of each type using analysis of variance and suggests implications for the strategic management of trade claims from a relational perspective. Findings - Results show that trade claims are divided into four clusters, depending on whether flexibility is accepted or not and which party violates mutuality. There is also a difference between the claimant and the cause of the claim, according to the cluster. Based on the results, this study suggests that the buyer and the seller should employ different strategies depending on the type of trade claim and presents proposals for strategic claim management. Originality/value - Firstly, this study extends the theoretical discussion on trade claims by applying relational contract theory. Prior studies on trade claims have been primarily based on traditional contract theory. The second is to analyze trade claims quantitatively. Prior case studies on trade claims have mainly relied on qualitative research. Finally, the study contributes to international commercial practice by typifying trade claims and presenting options for strategic management.