• Journal of Life Science
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• v.18 no.2
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• pp.206-212
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• 2008

The quorum sensing (QS) regulatory network has been the subject of extensive studies during recent years and has also attracted a lot of attention because it both positively and negatively regulates various putative virulence factors, although initially considered to be a specialized system of Vibrio fischeri and related species. In this study, to identify the novel materials which inhibit QS system of microorganisms, extracts of eighteen natural products were tested by bioassay using N-(3-oxohexanoyl)-$_L$-homoserine lactone and N-(3-oxooctanoyl)-$_L$-homoserine lactone synthesized in this experiment and an Agrobacterium tumefaciens NT1 biosensor strain containing a traI::lacZ fusion. The result indicated that the extracts of cabbage, leek, and onion exhibited the QS inhibition activity. Thus, materials contained in the extracts were isolated via recycling preparative HPLC and were purified via a JAIGEL-LS255 column. The common fraction corresponding to a peak of the 83 min point of them quenched the quorum sensing of A. tumefaciens NT1 biosensor strain in ABMM containing X-gal and was designated quorum sensing inhibitor-83 min (QSI-83). The QSI-83 exhibited the heat stability and did not inhibit the growth of A. tumefaciens NTl. Furthermore, thin layer chromatography (TLC) results suggested that these novel materials may be antagonists of N-acyl homoserine lactone or may inhibit the QS autoinducer synthesis by Pseudomonas syringae pv. tabaci.

• Annual Conference on Human and Language Technology
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• 1997.10a
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• pp.469-476
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• 1997

본 연구는 한글 전용과 한자 혼용이 글의 이해 속도, 이해 정도, 내용의 기억에 어떤 영향을 미치는 가를 조사하기 위해 실시되었다. 한글 전용론과 한자 혼용론은 각각 나름대로의 논리를 가지고 서로 논쟁을 펼쳐왔다. 먼저 한글전용론의 주장을 살펴보면, 한자는 배우기 어렵고 쓰기도 불편해 쉽게 익힐 수 있는 한글을 사용해야 하며, 한자를 사용함으로 인해서 순 우리말의 발전이 방해를 받고, 글자 생활의 기계화와 출판 문화의 발달에 있어 한자는 이것을 어렵게 한다는 것이다. 반면에, 한자혼용론의 주장에 따르면, 한자말은 한자로 적을 때 그 의미의 파악이 빠르고 정확하고, 우리말 어휘의 절반 이상을 한자어가 차지하고 있으므로 한자를 가르치는 것이 국어교육의 지름길이고, 우리말에는 동음이의어가 많아서 한글로만 적을 경우 그 뜻을 식별하기 어렵고, 한자는 각 글자가 모두 뜻을 가지고 있으므로, 각각을 조합하여 새로운 의미의 단어를 쉽게 만들 수 있음은 물론이고 한글로 쓸 경우 길게 쓰여져야만 하는 것을 짧게 쓸 수 있다는 장점을 가지고 있으며, 한자를 쓰지 않으면 우리의 전통 문화를 이어 받을 수 없으며 한자를 공통으로 쓰고 있는 동양문화권에서도 고립을 초래할 수 있다는 것이다. 이렇게 한글전용과 한자혼용에 대한 의견이 다양한 만큼 우리나라의 한자에 대한 정책도 그 갈피를 잡지 못하고 계속 바뀌어 왔다. 독립이후 정부에서는 법령과 훈령 등으로 모든 공문서에서의 한자사용을 금지하고 일반 사회의 문자 생활에도 한글을 전용할 것을 권고하지만 이 지침은 결국 공문서에만 한정되어 왔고 후에는 이것조차도 유명무실해졌다. 또한 중고등학교의 한자교육 정책도 수차례 변화되어 한글만을 배운 세대가 사회에 나와 여전히 한자가 사용되고 있어 적응에 문제점을 가지기도 하였다. 본 연구에서는 그 동안 계속되어 온 한글과 한잔의 사용에 관한 논쟁을 언어심리학적인 연구 방법을 통해 조사하였다. 즉, 글을 읽는 속도, 글의 의미를 얼마나 정확하게 이해했는지, 어느 것이 더 기억에 오래 남는지를 측정하여 어느 쪽의 입장이 옮은 지를 판단하는 것이다. 실험 결과는 문장을 읽는 시간에서는 한글 전용문인 경우에 월등히 빨랐다. 그러나. 내용에 대한 기억 검사에서는 국한 혼용 조건에서 더 우수하였다. 반면에, 이해력 검사에서는 천장 효과(Ceiling effect)로 두 조건간에 차이가 없었다. 따라서, 본 실험 결과에 따르면, 글의 읽기 속도가 중요한 문서에서는 한글 전용이 좋은 반면에 글의 내용 기억이 강조되는 경우에는 한자를 혼용하는 것이 더 효율적이다.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.364-369
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• 2002

Streptomyces shows a eukaryotic characteristic that vegetative cell can grow into mycelial form and has morphological and physiological differentiation at a certain period during its life cycle. Streptomyces has been used for the production of many biologically active compounds, such as antibiotics and pronase. Production of second metabolites and differentiation of the vegetative cell share the certain period of its lift cycle. Therefore, second metabolites may affect the differentiation of the vegetative cell. One of the microbial hormone, called A-factor, regulates the production of second metabolites, sporulation and differentiation of the cells. Streptomyces griseus produces streptomycin as well as many different kinds of proteinase. As mentioned, period of proteinases production overlaps with the period of differentiation of the vegetative cells. Protease may play a important role for the differentiation of the cells. In this paper, function of the SGPD gene cloned from S. griseus IFO 13350 tested whether it affects for the differentiation of A-factor mutated S. griseus HH1 and S. griseus IFO13350. pWHM3 and pWHM3-sprD plasmid was transformed into S. griseus HH1 and S. griseus IFO13350. Chymotrypsin activity of the cultured medium of the transformants with pWHM3-sprD plasmid didn't show any change with that of the transformants with plasmid only. The transformants with pWHM3-sprD plasmid didn't show the increase of the production of actinorhodin as well as morphological change in S. griseus IFO 13350 and HH1, as well. The promoter sequences of the SGPA and SGPB gene which encode chymotrypsin-like protease, were compared with that of SGPD gene. Regulatory mechanism of gene expression of proteinase genes will be studied for the development of high production system for protease as well as the function of the proteases.

• Journal of Technology Innovation
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• v.24 no.4
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• pp.127-158
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• 2016

Multinational corporations' overseas R&D activities bring host countries positive effects such as knowledge spillover, technology transfer, job creation and etc. For this reason, many countries have made efforts to attract foreign firms' R&D investment in their national territories. Korean government have also implemented some policy measures to expedite foreign firms operating in Korea to increase R&D activities. However, the firms' R&D investment in Korea has still been unsatisfactory, and only few studies have examined this issue. Therefore, this study attempts to explain the R&D investment of foreign firms operating in Kore, from the perspective Dunning's eclectic paradigm. Utilizing linear regression and Tobit model, this study analyzes the influence of OLI advantages on R&D intensity of foreign firms in Korea. The result shows that locational advantages of Korea (such as revealed technological advantage) had positive influences on foreign firms' R&D intensity. However, the influence of other OLI advantages were different by foreign firms' nationalities. For instance, internalization advantages had influences on R&D intensity, but the directions were different between Japanese and other nationalities. Based on the results, we provided some discussion and attempted to draw implications for Korean government's FDI and R&D policy.

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.586-596
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• 2011

In the IT industry, processing units of IT applications are getting smaller and high efficient. Furthermore, the realization of various smart functions is highly feasible now due to advances in sensing technology. The service infrastructures on high efficient and compact mobile devices are applied to various areas. These also could be possessed by users and is built into the devices. Currently, studies on the UX(User Experience) field to attempt an analysis and prediction of user's information are continuing with reference to the UI(User Interface). However, research on the common framework of classification and storing the user-information, and standardization of form has not been attempted yet. In this study, we proposed the AUX(Associative user Experience) model and process structure to store various empirical data by users. The AUX model expressed a diversity of user's empirical data using extended E-TCPN model. And also, we expressed the data structure using XML with reference to the application of AUX model. This expressed model and separation of process structure guarantee its specialty, productivity and flexibility through the humanistic characteristics of users and the independence of technical process structure. The AUX model maps out the AUX information process architecture and expressed the process with the improved MPP algorithm, to analyze of its performance. The simulation of movements applying to MPP traffic allocation of VOD is used to analyze of its performance. The playback deviation of MPP Graphic Allocation Algorism where the AUX model was applied was improved by 10.41% more than the one where it was not applied. As a result of that, playback performance has improved due to the conversion of AUX with accessing media, content of users and dynamic traffic allocation such as MPI and CPI.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.636-652
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• 2018

This study is about applying the concept of moral injury in reinterpreting and understanding the experience of female North Korean refugees who have experienced psychological trauma and are struggling with adjusting in their everyday lives. The database KISS and DBpia were used to search for academic peer-reviewed articles published before August 13th in 2017, using 'female or women North Korean,' 'female or women relocated North Korean,' and 'female or women North Korean defector' as keywords. In total 51 studies were finally selected for content analysis and the result were the following. First, listing from the most often occurring study topic to the least occurring topic in order: post-defection adjustment related, mothering experience, experience of North Korean regime and Korean War, work or job or employment related, recovering from psychological trauma as well as growth and resilience related, experiences in China, trauma and psychological difficulties, anxiety treatment process and effects. Second, words related to psychological aspect of moral injury appeared 260 times in 51 selected studies, changes in the existential belief appeared 82 times, cognitive aspects of moral injury appeared 71 times, and behavioral aspects 21 times. Third, two main contexts emerged to be the antecedent that led to moral injury and they were 'identity denial' and 'dismantled family.' In attempts to find opposite cases or stories where aspects of moral injury were not found despite the existence of its antecedents and it was 'identity restructuring.' Based on the finding, practice implications that could help female North Korean refugees prevent or recover from moral injury were suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1699-1705
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• 2012

This study was conducted to examine the differences of the quality of chest compression between 10 cm higher position of rescuer's knee from the bottom and its bottom position during implementation of CPR. It selected randomly subjects out of 66 students who attend the Dept. of Emergency Medical Technology in G college, G metropolitan city as the first grader and divided them into 31 experimental group and 32 control group from Nov. 8 to 9, 2011. Mattress was spread 10 cm higher from the bottom(material: B4 Copy Paper) and on the bottom(material: PVC, size: $185{\times}125{\times}0.65cm$) and only chest compression was conducted for 2 minutes. Experiment was conducted with 1 Resusci Anne mannequin and the results of experiment were recorded with Laerdal PC Skill Reporting System. Data collected were analyzed with $x^2$-test and Fisher's exact probability test using SPSS 14.0 for Window, Mann-Whitney U-test, and Wilcoxon signed rank test. As a result of the study, it was found that 10 cm higher position of rescuer knee from the bottom than the bottom position and group below 170 cm in their height and 65 kg in their weight were more effective in proper depth of chest compression and average chest compression depth.

• Journal of Distribution Research
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• v.16 no.4
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• pp.95-127
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• 2011

Developing our understanding of retail employee job satisfaction is important, especially given its impact in reducing employee turnover intentions and increasing employee job performance. While developing our understanding of job satisfaction is important, the vast majority of studies examine job satisfaction as a global or single-faceted construct. However, extant research provides evidence that to properly measure job satisfaction, multi-faceted scales are required (e.g. Churchill et al., 1974; Boles et al., 2007; Rutherford et al., 2009). Using the literature on multi-faceted job satisfaction, this study examines retail employees' satisfaction with supervision, job, company policy, promotion, pay, fellow workers, and customers. Specifically, emotional exhaustion, need for emotion, and personal traits (strong, independent, and warm) are examined as antecedents. This study finds that emotional exhaustion is negatively related to all seven facets of job satisfaction.

• Applied Biological Chemistry
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• v.45 no.4
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• pp.195-202
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• 2002

The cytotoxic, mutagenic and antimutagenic activities against chemical direct mutagens such as mitomycin C, 4-nitroquinoline-N-oxide, 2,4,7-trinitro-9-fluorenone of the 70% ethanol extracts of 29 colored rice varieties and chuchung as a control were examined. The results obtained using authentic alkaline phosphatase activity as a growth representative of the indicator cell E. coli PQ 37 demonstrated that the extracts of 13 kinds of colored rice varieties including Jumlalocal and Jumlalocal-1 showed strong toxic effect on the cell growth. However the extracts of DK 1, SC-5, LK 1A-2-12-1-1 and wx 139-3-64-20-3-1 seemed to have stimulatory effects on the cell growth. The mutagenicity and antimutagenicity of the colored rice varieties were screened using SOS chromotest. The mutagenic activity was detected from Jumalocal-1, IR 17491-5-4-3-3 and Jumlalocal. On the contrary, 7 samples including LK 1-3-6-12-1-1, Parnkhari 203, Jumlalocal, wx 139-3-64-20-3-1, Muthumanikam, HP 883-1-1-1-B-1-1 and Jumlalocal-1 were shown to have antimutagenic acitivities against the chemical direct mutagens used in this study.

• Journal of The Korean Association For Science Education
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• v.34 no.7
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• pp.635-645
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• 2014

The purpose of this study is to identify elementary school teachers' perceptions, practices, and background factors related to introducing students' everyday experience in science teaching process. The participants of this study were four elementary school teachers who have different features such as major, teaching period, gender, growth area, and age. The data was collected through semi-constructed and in-depth interviews. The results of the research are as follows: Teachers mostly used students' everyday experience during the introduction phase of science lessons for the purpose of motivation. They hold a positive view of using students' everyday experience during science lessons and thought that science teaching needs to actively use more of students' everyday experience, while in actual practice they disregarded or only passively introduced students' everyday experience. The various background factors found to affect teachers' practice are as follows: positive memory on their science class; educational experience of their own children; their own childhood environment; their learning style; their insufficient knowledge or enthusiasm; perceived educational value of everyday life in science education; teacher's duties; importance of students' achievement; difficulty in guiding experiment; reaction of students on introducing everyday experience; characteristics of science textbook and teacher's guidebook; lack of lesson time; realization of national common basic education; characteristics of their students; demands from parents or students; effect of introducing everyday experience. In addition, we found that the teachers behave not in accordance with what they thought due to external factors related to their profession and that, for a more active use of students' everyday experience in their teaching, teachers need support from textbooks and teachers' guidebooks.