• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.5
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• pp.38-48
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• 2007

In ubiquitous environment, sensor networks that sense and transmit surrounding data without human intervention will become more important. If sensors are installed for detecting vehicles and measuring their speed in the road and that real-time information is given to drivers, it will be very effective for enhancing safety and controlling traffic in the road. In this paper, we proposed a new reliable and real-time sensor MAC protocol between AP and sensor nodes in order to provide real-time traffic flow information based on ubiquitous sensor networks. The proposed MAC allocates one TDMA slot for each sensor node on the IEEE 802.15.4 based channel structure, introduces relayed communication for distant sensors, and adopts a frame structure that supports retransmission for the case of errors. In addition, the proposed MAC synchronizes with AP by using beacon and adopts a hybrid tracking mode that supports economic power consumption according to various traffic situations, We implemented a simulator for the proposed MAC by using sim++ and evaluated various performances. The simulation results show that the proposed MAC reduces the power consumption and reveals excellent performance in real-time application systems.

• Journal of the Korean Chemical Society
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• v.59 no.6
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• pp.520-532
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• 2015

The purposes of this study were to examine what kinds of educational activities were carried out during the practice teaching based on CoRe and to identify the role of CoRe and its influence on the development of expertise of student teachers. This study was performed as qualitative case study. The subjects of this study were one practice supervisor teacher and two student teachers. Data were collected through recording CoRe discussion process, student teachers' instructional scene, and semi-constructed interview, and analyzed by an inductive method. Student teachers noticed their own misconceptions, and clarified the concepts based on CoRe during the discussion with supervisor teacher. They also supplemented their lack of knowledge and made up new strategies through the process of sharing their ideas. During the discussion, the supervisor teacher conveyed his teaching experience based on his own orientations toward science teaching. In this course, CoRe plays roles as follows. Firstly, CoRe played a role as guiding supervisor teacher's coaching process. Secondly, CoRe helped for the supervisor teacher to recognize their own PCK. Thirdly, CoRe served as a tool of helping their communication. In turn CoRe proved to be a useful frame for teaching student teachers during practice teaching. Student teachers were provided with a useful framework for preparing lessons by developing CoRe for the topic they teach. Developing CoRe with supervisor teacher at the planning stage of lessons enhenced student-teachers' subject matter knowledge and their PCK including knowledge of science curricula and knowledge of student's understanding of science. Also student teachers understood the components of PCK and experienced the positive understanding toward students, teaching activities, and themselves as a science teacher.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.575-584
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• 2015

Drought stress is a crucial environmental factor determining crop survival and productivity. The goal of this study was to clearly identify a new drought stress-tolerance gene in Brassica rapa. From KBGP-24K microarray data with the B. rapa ssp. pekinensis inbred line 'Chiifu' under drought stress treatment, a gene which was named BrDSR (B. rapa Drought Stress Resistance) was chosen among 738 drought-responsive unigenes. BrDSR function has yet to be determined, but its expression was induced over 6-fold by drought. To characterize BrDSR, the gene was isolated from B. rapa inbred line 'CT001' and found to contain a 438-bp open reading frame encoding a 145 amino acid protein. The full-length cDNA of BrDSR was used to construct an over-expression vector, 'pSL100'. Tobacco transformation was then conducted to analyze whether the BrDSR gene can increase drought tolerance in plants. The BrDSR expression level in T1 transgenic tobacco plants selected via PCR and DNA blot analyses was up to 2.6-fold higher than non-transgenic tobacco. Analysis of phenotype clearly showed that BrDSR-expressing tobacco plants exhibited more tolerance than wild type under 10 d drought stress. Taking all of these findings together, we expect that BrDSR functions effectively in plant growth and survival of drought stress conditions.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.179-185
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• 2002

Purpose : For the purpose of quality assurance of self-developed stereotactic radiosurgery system, a multi-purpose phantom was fabricated, and accuracy of radiation dose distribution during radiosurgery was measured using this phantom. Materials and Methods : A farmer chamber, a 0.125 cc ion chamber and a diode detector were used for the dosimetry. Six MV x-ray from a linear accelerator (CL2100C, Varian) with stereotactic radiosurgery technique (Green Knife) was used, and multi-purpose phantom was attached to a stereotactic frame (Fisher type). Dosimetry was done by combinations of locations of the detectors in the phantom, fixed or arc beams, gantry angles $(20^{\circ}\~100^{\circ})$, and size of the circular tertiary collimators (inner diameters of $10\~40\;mm$). Results : The measurement error was less than $0.5\%$ by Farmer chamber, $0.5\%$ for 0.125 cc ion chamber, and less than $2\%$ for diode detector for the fixed beam, single arc beam, and 5-arc beam setup. Conclusion : We confirmed the accuracy of dose distribution with the radiosurgery system developed in our institute and the data from this study would be able to be effectively used for the improvement of quality assurance of stereotactic radiosurgery or fractionated stereotactic radiotherapy system.

• Korean Journal of Childcare and Education
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• v.7 no.3
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• pp.143-164
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• 2011

The purpose of this study was to examine toddlers' experienced world, which was shown in a play of the nature-friendly outdoor environment. Through this, the aim was to offer an opportunity of trying to seek a plan for activation in the nature-friendly outdoor play as for toddlers. This study targeted 9 toddlers between 22 months and 33 months who are attending S child care center where is located in Busan Metropolitan City, and was progressed with qualitative research method available for examining the in-depth significance of the phenomenon. A method of data collection was carried out the participatory observation and the in-depth interview. As a result of the study, the toddlers play experience in nature friendly outdoor environment provided special and various experience that can be limited in indoor at daycare center. First, toddlers were experiencing 'exploratory world of making a sense awakened.' Second, toddlers were experiencing 'communicative world of making emotion awakened.' Finally, on the early childhood education and the child-care education, a plan of offering enough time will need to be pursued now that toddlers can experience a play by being deeply immersed in nature, which is the space of free communication and the living sensational space, with escaping from the existing frame.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.1981-1987
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• 2014

Objective: To establish the prevalence and distribution profile of esophageal squamous cell carcinomas (ESCCs) over a 22-yr period in North China. Methods: Using endoscopy for primary diagnosis and histological analysis for the further confirmation, a total of 74,854 ESCC patients aged 20-89 between January 1985 and December 2006 were investigated to analyze the epidemiological profile including prevalence rates, distribution of age-of-onset, gender and geographical area of ESCC in Luoyang, the highest incidence area of North China. Results: A total of 4092 cases of ESCC were finally diagnosed among 74,854 patients who had their first endoscopies. The prevalence among males was higher than that among females (p<0.01), resulting in an overall male:female OR of 1.2 (95%CI, 1.2-1.3). The prevalence in rural areas was higher than in urban areas (p<0.01), resulting in an overall rural:urban OR of 2.6 (95%CI, 2.4-2.9). The rural:urban ORs and the 95% CI increased continuously from 2.6, 2.3-3.0 to 2.7, 2.2-3.3, respectively, for 4 consecutive periods during the 22-yr study period. Moreover, the median age of onset among females was higher than that among males (p<0.01). For both sexes and in both areas, the prevalence rates declined and the median age of onset rose for 4 consecutive periods in the 22-yrs time frame (p<0.01). Conculsions: These data reveal the epidemiological profile of ESCC in the area of North China, and suggest that urban areas and rural people account for a growing proportion of the ESCC patients although the prevalence of ESCC significantly declined and the median age-of-onset postponed over the 22-yrs period. Moreover, the prevalence status of ESCC in rural areas also underlines the need for public health initiatives aimed at reducing risk factors of this fatal disease.

• BMB Reports
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• v.34 no.4
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• pp.334-341
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• 2001

Even though three isotypes of thioredoxins (-f, -m and -h types) have been identified in a variety of plant cells, there are only a few reports on thioredoxin-h that were recently identified. In this study, a cDNA encoding a h-type of thioredoxin was isolated from a cDNA library of Chinese cabbage, and named here CTrx-h. An open reading frame of the gene contained a polypeptide of 133 amino acids with a conserved active center, WCGPC, which appeared in all of the thioredoxin proteins. A deduced amino acid sequence of the CTrx-h showed the highest sequence identity with those of Arabidopsis thioredoxin-h2 (75.2%) and thioredoxin-h5 (46.6%) proteins, but it shared a low sequence homology to other isotypes of plant thioredoxinm and thioredoxin-f. The CTrx-h protein that is expressed in E. coli represented not only an insulin reduction activity, but also electron transferring activity from NADPH to thioredoxin-dependent peroxidase. A genomic Southern blot analysis using the cDNA insert of CTrx-h revealed that the gene consisted of a small multigene family in Chinese cabbage genome. On the contrary to other thioredoxin-h proteins that were widely distributed in most tissues of the plant, the CTrx-h was predominantly expressed in flowers. The expression was very low in other tissues. The data of the Northern blot analysis suggests that the CTrx-h may have other functions in flower development or differentiation, in addition to its defensive role.

• 한국벤처창업학회:학술대회논문집
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• 2007.04a
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• pp.35-64
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• 2007

Despite the tremendous efforts to boost them, domestic SMEs lack competitive power and it intensifies bipolarization between the conglomerates and SMEs. Furthermore, degree of industry-academy collaboration still falls far behind of that of developed countries even with government' s various policies and continuous increase in investment to strengthen the SMEs' technology innovation capability. Although many internal factors are suggested to affect technological performance, focus of existing studies has been restricted to immediate impact of industry-academy collaboration on technology innovation and it is not known how internal factors are related. This research conducts empirical analysis on the impact of industry-academy collaborations and absorptive capacity on technological performance in Korean SMEs. Sample frame is SMEs with more than five employees located in the nation wide industrial complex and 1,077 questionnaires are collected with the help of Korea Industrial Complex Corporations. 940 sample data excluding those with insufficient response are used in analysis. Multiple regression analysis revealed that the industry-academy collaborations and innovative HRM system, on important dimension of absorptive capacity, are positively correlated to technological performance. Furthermore, there exists a positive interaction effect between industry-academy collaborations and innovative HRM system. These findings make contributions to the formation of SME innovation policy and management. When funding industry-academy collaborations, government should consider SMEs' internal effort for innovation, that is, the possession of innovative HRM system, as well as firm's technology capability. Also, as technological performance cannot be achieved simply with R&D investment, both quantitative and qualitative assessment of SMEs' technological capability should be done to evaluate the candidate SMEs. As for management, it is important for SMEs with limited internal resources and capabilities to fully employ external resources to achieve higher technological performance. The development of innovative HRM system will be particularly helpful not only for internal R&D, but also for adoption of technology and knowledge from outside.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.211-220
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• 2011

The study conducted a survey on the perception level for radiological technologists with 321 nurses and auxiliary nurses working at university hospitals in Busan in order to supply preliminary data to enhance the status as well as professional images of radiological technologists. The result shows the perception level of $3.02{\pm}0.42$ with the highest score for the professional image and the lowest score for the business image. By question, 'they are professional' gets the highest score while 'they understand problems of patients well' gets the lowest. Among respondents, those who are well aware of education courses as well as leading organization of examination and who answer as a health care provider or a medical technician under the medical law show a high level of perception while those who answer as technician show a low perception level. Those who agree with radiologists as a career and consider their status as high in medical institutions have a high level of perception. In order to improve the perception level, individuals as well as associations' promotion and strategies are required to fix the title and enhance the negative images through active interests and kind attitudes toward patients. Also, efforts to escape from previous images limited to technical colleges, to vitalize academic conference and remedial education, and to frame the law of professional radiological technologists system are asked to heighten the qualification and status of radiological technologists. More than that, advertising and monitoring via mass media are needed to develop the image as professional career men as well.

• Informatization Policy
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• v.23 no.2
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• pp.73-97
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• 2016

Social changes due to ICT like Big Data, IoT, Cloud and Mobile is progressing rapidly. Now, we get out of the old-fashioned frame was measured at the level of the information society through the introduction of PC, Internet speed and Internet subscribers etc and there is a need for a new type of diagnostic information society framework. This study is the study for the framework established to diagnose and measure post-information society. The framework and indicators were chosen in accordance with the technological society coevolution theory and information society-related indicators presented from authoritative international organizations. Empirical results utilizing the indicators and framework developed in this study were as follows: First, the three sectors, six clusters (items), 25 nodes (indicators) that make up the information society showed that all strongly connected. Second, it was diagnosed as information society development (50.34%), technology-based expansion (25.03%) and ICT effect (24.63%) through a network analysis (ANP) for the measurement of importance of the information society. Third, the result of calculating the relative importance of the cluster and nodes showed us (1)social development potential (26.04%), (2)competitiveness (15.9%), (3)ICT literacy (15.5%) (4) (social)capital (24.3 %), (5)ICT acceptance(9.54%), (6)quality of life(8.7%). Consequently, We should take into account the effect of the economy and quality of life beyond ICT infrastructure-centric when we measure the post-information society. By applying the weighting we should performs a comparison between countries and we should diagnose the level of Korea and provide policy implications for the preparation of post-information society.