• Journal of Communications and Networks
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• v.7 no.4
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• pp.462-470
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• 2005

We propose a multi-rate and multi-BEP transmission scheme using adaptive overlapping pulse-position modulator (OPPM) and optical power controller in optical code division multiple access (CDMA) networks. The proposed system achieves the multi-rate and multi-BEP transmission by accommodating users with different values of OPPM parameter and transmitted power in the same network. The proposed scheme has advantages that the system is not required to change the code length and number of weight depending on the required bit rate of a user and the difference of bit rates does not have so much effect on the bit error probabilities (BEPs). Moreover, the difference of transmitted powers does not cause the change of bit rate. We analyze the BEPs of the four multimedia service classes corresponding to the com­binations of high/low-rates and low/high-BEPs and show that the proposed scheme can easily achieve distinct differentiation of the service classes with the simple system configuration.

• Journal of the Korean Society of Food Culture
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• v.4 no.3
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• pp.213-219
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• 1989

In this paper we investigate the table settings of Korean ceremonial foods for Honrye (a marriage ceremony) and Jerye (sacrificial rituals). According to the procedure of Honrye, the tables for Honrye are to be the divided into four classes; Bongchisang for Nappe ceremony, Choroyechungsang for Chorye ceremony, Keunsang for the bride and bridegroom and Pyebecksang for Kyungugorye ceremony. Jerye is to be divided into several classes; Shunjoje, Shijoje, Leeje, Kheeilje, Myoje, Sokjeulje, Sasije, and so on. Foods for Jerye are a little different from those for Honrye, but the form of table settings for Jerye is similar to that of Keunsang in Horye. Each table setting for Honrye and Jerye has its own form, that represents the meaning of that ceremony. Furthermore, foods prepared for Honrye and Jerye have the Korean dual principle of the negative and positive.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1470-1479
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• 1996

It was already proved that ATM has stability and flexibility of service applications, but because of the various characteristics of traffic and the QoS on user demandcaused by them, there are so many researches for traffic control method. In this paper, in order to give the more similar properties of the real traffic to the existing input traffic source, dividing them into four classes with different characteristics, and We proposed the integrated dynamic priority method, IDP which has advantages of the DMLT and the DQLT for time dynamic priority. Thus, it makes input queues about each of traffic classes and thresholds, and then use modified DMLT and DQLT methods. It has goal that proposed method to get more reliability and stability with advantage low loss of the DMLT, low delay of DQLT.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.205-211
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• 2001

The floristic composition and structure of the Oriental Arbor-viate forest, natural monument no. 1, were investigated in the Daegu city, southeastern Korea. Vegetation stratification have four layers including tree (＞5m), subtree (2m-5m), shrub (1m-2m) and herbs (＜1m), which occupied 63.8%, 10.7%, 12.1% and 49.4%, respectively. The vegetation of the study area were divided into Artemisia keiskeana - Quercus variabilis and Pyrrosia linearifolia-Thuja orientalis (OAV) communities. Frequency distribution for diameter classes of the Oriental Arbor-vitae population showed a reverse-J shape. The result suggests that the OAV forest of this site might maintains continuously the present state. The annual radial growth of OAV, Pinus densiflora and Quercus variabilis, the dominant species of the present site showed 0.29, 1.01 and 1.28 mm/year, respectively. Competition of OAV with theh other species including P. densiflora and Q. variabilis could influence negatively on the growthand survival of OAV forest in this site.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.516-521
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• 2006

The use of gltA gene, as a new biomarker for environmental stress biomonitoring, was investigated because of its key position as the first enzyme of the tricarboxylic acid (TCA) cycle. A recombinant bioluminescent Escherichia coli strain, EBJM2, was constructed using a plasmid carrying the citrate synthase (gltA) promoter transcribing the Photorhabdus luminescens IuxCDABE genes (gltA::luxCDABE). The responses from this strain were studied with five different classes of toxicants: DNA damage chemicals, phenolics, oxidative-stress chemicals, PAHs, and organic solvents. EBJM2 responded strongly to DNA damage chemicals, such as mitomycin C (MMC) and methyl-nitro-nitrosoguanidine (MNNG) and nalidixic acid with the strongest responses. In contrast, tests with several compounds from the other four classes of toxicants gave no significant response. Therefore, EBJM2 was found to be sensitive to DNA damage chemicals.

• Korean Journal of Remote Sensing
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• v.19 no.5
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• pp.381-392
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• 2003

Multi-temporal approaches using sequential data acquired over multiple years are essential for satisfactory discrimination between many land-cover classes whose signatures exhibit seasonal trends. At any particular time, the response of several classes may be indistinguishable. A harmonic model that can represent seasonal variability is characterized by four components: mean level, frequency, phase and amplitude. The trigonometric components of the harmonic function inherently contain temporal information about changes in land-cover characteristics. Using the estimates which are obtained from sequential images through spectral analysis, seasonal periodicity can be incorporates into multi-temporal classification. The Normalized Difference Vegetation Index (NDVI) was computed for one week composites of the Advanced Very High Resolution Radiometer (AVHRR) imagery over the Korean peninsula for 1996 ～ 2000 using a dynamic technique. Land-cover types were then classified both with the estimated harmonic components using an unsupervised classification approach based on a hierarchical clustering algorithm. The results of the classification using the harmonic components show that the new approach is potentially very effective for identifying land-cover types by the analysis of its multi-temporal behavior.

• International Journal of Advanced Culture Technology
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• v.12 no.3
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• pp.237-242
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• 2024

Lecturers' self-efficacy in teaching influences many different factors, including their instructional patterns, performance expectation level from learners, quality of learning environment, and interpersonal relationships within the community. The present study attempted to explore perspectives of college lecturers regarding this topic in order to draw meaningful conclusions and implications. To this end, four college instructors from two different higher education institutions participated in an online questionnaire. The results showed that positive attitudes and active responses of learners, and a high degree of freedom to prepare lectures tend to improve their quality of self-efficacy in teaching. On the other hand, classes that are either too easy to hard, inactiveness among learners, and heavy workload other than teaching can worsen teaching efficacy. Lastly, the participant lecturers believed that their self-efficacy are would foster if they are allowed to choose courses they wish to teach, observe a more experienced instructor's lectures, and teach smaller size classes. Findings are likely to contribute to enhanced understanding of features that are likely to affect quality of self-efficacy in teaching among college lecturers.

• Korean Journal of Child Studies
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• v.13 no.2
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• pp.33-51
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• 1992

The purpose of this study was to investigate activities of kindergarteners in the mathematics corner. The study included an analysis of children's interactions with mathematics materials and of children's peer interactions during mathematics activities. The subjects were 47 children aged three to four and 72 children aged four to five from four classes of two kindergartens in Kwangju. Children's math activities during free play sessions were observed and audiotaped. The data were coded by the categories of children's peer interactions and types of mathematics manipulations. The characteristics of children's peer interactions and materials frequently selected by the subjects were identified. The results indicated that (1) most of the math materials were for passive manipulation that require children to respond according to predetermined conditions like the rules of games, but (2) the materials that children liked to play with were active manipulative materials that require diversity and flexibility of children's thinking and allow several choices for solutions, and (3) children's peer interactions during math activities were categorized into unilateral and reciprocal/collaborative peer interaction type.

• Journal of dental hygiene science
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• v.17 no.3
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• pp.242-249
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• 2017

The purpose of this study was to investigate the level of cultural competence and its influencing factors among 530 dental hygiene students. The analysis was performed using PASW Statistics ver. 18.0, and the following conclusions were drawn. Cultural knowledge levels showed a significant difference according to general characteristics in four components of cultural competence levels. Cultural competence and its four components were higher in subjects who have a religion (p<0.05). The differences in cultural competence levels according to culture-related characteristics are as follows. In individuals with experience of taking foreign culture-related classes, intention to work overseas, or fluency in a foreign language, cultural competence levels and its four components such as cultural comfort, knowledge, awareness, and behavior intent were higher (p<0.05). Intention of overseas employment was the factor most strongly influencing the level of cultural competence of the subjects. The more intention the subjects have to work overseas, the more they have experienced foreign culture-related lessons, the more fluently they speak a foreign language, and the higher level of cultural competency they reached (p<0.05). As the research results show, it is necessary to establish a continuing plan to understand and communicate with individuals of other cultures through foreign language and foreign culture classes in schools in order to improve the level of cultural competence. This education would reduce the fear and stress that subjects might make a mistake in meeting with people from other cultures, and it could be a preparatory process to actively carry out dental hygiene practice with foreigners.

• Journal of Korean Dental Hygiene Science
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• v.5 no.2
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• pp.113-121
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• 2022

Background: This study aimed to create and present content that can be used in the dental hygiene ethics process to help dental hygiene students develop desirable work ethics and ethical values. Methods: In order to operate the dental hygiene ethics course in all academic systems, one three-year dental hygiene professor and one four-year dental hygiene professor participated in setting core competencies and learning goals for the dental hygiene ethics course. The class consisted of two credits, two hours of theoretical classes, and class activity sheets developed according to the learning contents and learning topics for each week that can be operated for 15 weeks. Results: The contents of the dental hygiene ethics subject were developed to be conducted as theoretical education and case-oriented discussion classes. The 15-week class consisted of a theory lecture on dental hygiene work ethics (eight weeks), discussions and presentations for ethical decisions based on actual cases related to dental hygiene ethics (four weeks), and the design and presentation of individual professional mission statements and codes of conduct (three weeks). The class data for each week consisted of four stages: "Learning goal-thinking," "open-thinking," "learning content-thinking," and "according to learning goal." Conclusions: In order to establish desirable workplace ethics and ethical values for dental hygiene students, it is necessary to approach education in a way that values understanding and application of dental hygiene practices, legal and ethical standards, ethical decision-making models, and ethical principles.