• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.6
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• pp.989-1005
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• 2010

Cooperative diversity is a technique with which a virtual multiple antenna array is established among the single antenna users of the wireless network to realize space diversity. Signal space diversity (SSD) is a bandwidth-efficient diversity technique, which uses constellation rotation and interleaving techniques to achieve diversity gain. A new cooperative diversity scheme with rotated constellations (RCCD) is proposed in this paper. In this scheme, data are modulated by using a rotated constellation, and the source and the relays transmit different components of the modulated symbols. Since any one of the components contains full information of the symbols, the destination can obtain multiple signals conveying the same information from different users. In this way, space diversity is achieved. The RCCD scheme inherits the advantage of SSD - being bandwidth-efficient but without the delay problem of SSD brought by interleaving. The symbol error rate of the RCCD scheme is analyzed and simulated. The analysis and simulation results show that the RCCD scheme can achieve full diversity order of two when the inter-user channel is good enough, and, with the same bandwidth efficiency, has a better performance than amplify-and-forward and detect-and-forward methods.

• Journal of Korean Academy of Nursing
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• v.37 no.2
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• pp.208-212
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• 2007

Cultural diversity is a highly important issue in nursing education and nursing practice today. This study is a philosophical approach to the power relationship between a health care provider and a care recipient. The main purpose of this paper is to analyze the relationships between nurses and ethnic minority patients based on the discussions of some Foucauldian concepts that are related to cultural diversity. Based on the analysis, this study provides some suggestions for cultural competency in nursing practice.

• BMB Reports
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• v.40 no.6
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• pp.845-852
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• 2007

The highly evolved flowers of orchids have colorful sepals and fused columns that offer an opportunity to discover new genes involved in floral development in monocotyledon species. In this investigation, we cloned and characterized the homologous PISTALLATA-like (PI-like) gene PhPI15 ($\underline{Ph}alaenopsis$ $\underline{PI}$ STILLATA # $\underline{15}$), from the Phalaenopsis hybrid cultivar. The protein sequence encoded by PhPI15 contains a typical PI-motif. Its sequence also formed a subclade with other monocot PI-type genes in phylogenetic analysis. Southern analysis showed that PhPI15 was present in the Phalaenopsis orchid genome as a single copy. Furthermore, it was expressed in all the whorls of the Phalaenopsis flower, while no expression was detected in vegetative organs. The flowers of transgenic tobacco plants ectopically expressing PhPI15 showed male-sterile phenotypes. Thus, as a Class-B MADS-box gene, PhPI15 specifies floral organ identity in orchids.

• Journal of Nutrition and Health
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• v.30 no.7
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• pp.854-869
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• 1997

This study was conducted to evaluation the quality of meals served in elementary school based on nutrient contents and food diversity . A questionnaire was mailed to school foodservice dietitians requesting one week menus for April and October . Menus served in 388 schools from each province and from major cities in Korea were analyzed. Mean nutrient contents per meal of persons served, and food expenses per meal. Mean percentages of energy from fat was 20.2% , and was significantly l different by foodservice system. When nutrient contents were converted to amount per 1, 000kcal, all were higher than that calculated from RDA except calcium, iron, and Vitamin A. Most of these were not significantly different according to area, foodservice system, the number of persons served, and food expense per meal. Compared to 1/3 of RDA for children , many meals provided lower amounts of energy, Vit A, VitB2, and Ca. More than half of the meals provided less iron than 1/3 RDA for 10-12 years girls. Using the highest values of RDA for the elementary school age group as evaluation, criteria nutrient adequacy ratios(NAR) were lowest for Ca(0.61), Vit A(0.57), and iron(0.77). The mean adequacy ratio(MAR) was 0.86. Mean numbers of food items and dishes per meal were 15.3 and 5.1 , respectively. 66.3% of the meals provided three food groups of grain, meat, and vegetable. Except for the number of different food items served per meal, the aspect of food diversity was similar to that of nutrient contents. There was significant positive correlation between mean number of different food items served per meal and nutrient content . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those or density. Also the more food groups served per meal, the higher the nutrient content per meal . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those adapting conventional foodservice system, schools serving smaller number of persons, and schools with higher food expenses provided higher energy contents and food diversity.

• Journal of Global Scholars of Marketing Science
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• v.7
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• pp.71-103
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• 2001

Marketing practice varies among firms. However, the prescriptive literature emphasises a universal view of practice, a 'one size fits all' view. This paper addresses the issue of explaining diversity in marketing practice in competitive space and in time. Diversity in competitive space reflects the existence of different routes to high performance. Diversity in time reflects some combination of change in the individual firm and change in a population of firms. In the former case, diversity is shaped by organisational change; in the latter by the disbandment and founding of firms in the population. In so far as diversity is the norm, the manner in which practice will be shaped by evolutionary processes is considered. Fnally, the role of the academy as one of the forces driving the evolutionary process is discussed. Miles and Snow's (1978, 1986) work is taken as a main point of departure in the search for explanation and ecological and evolutionary concepts are drawn on for support and to suggest an explanation for the nature of diversity over time.

• Journal of the Korea Society of Computer and Information
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• v.20 no.11
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• pp.77-88
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• 2015

This study attempts to investigate the effect of team diversity on individual creativity and team members' creative activities such as exploration and exploitation. We have garnered 40 team data from 249 respondents who have been participating in the team learning activities during semester in a private university. They were asked by instructor to show their creativity, and exploration and exploitation activities. The 40 teams were made up of team diversity factors such as study hour and leisure activity. We used a multilevel analysis to analyze the effects of team diversity factors on team member's creativity, and exploration and exploitation. Results showed that in general, team diversity factors like study hour and leisure activities have significant effects on the individual creativity, and exploration and exploitation. Practical implications represent that teams need to be organized considering the team diversity factors in order to improve team member's creativity, and their exploration and exploitation activities.

• BMB Reports
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• v.49 no.12
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• pp.662-670
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• 2016

The human oral cavity contains a highly personalized microbiome essential to maintaining health, but capable of causing oral and systemic diseases. Thus, an in-depth definition of "healthy oral microbiome" is critical to understanding variations in disease states from preclinical conditions, and disease onset through progressive states of disease. With rapid advances in DNA sequencing and analytical technologies, population-based studies have documented the range and diversity of both taxonomic compositions and functional potentials observed in the oral microbiome in healthy individuals. Besides factors specific to the host, such as age and race/ethnicity, environmental factors also appear to contribute to the variability of the healthy oral microbiome. Here, we review bioinformatic techniques for metagenomic datasets, including their strengths and limitations. In addition, we summarize the interpersonal and intrapersonal diversity of the oral microbiome, taking into consideration the recent large-scale and longitudinal studies, including the Human Microbiome Project.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.103-105
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• 2008

차세대 양방향데이터방송 (BIFS: BInary Format for Scenes) 서비스에서는 하향링크(downlink) 데이터 전송률에 상응하는 높은 상향링크(uplink) 데이터 전송률이 요구되고 있다. 이에 무선 전송 채널의 한정된 자원 환경 속에서 상향링크 전송용량 증대를 위한 주파수 효율성 제고 기술의 필요성이 대두되고 있다. 본 논문에서는 차세대 양방향데이터방송을 위한 다중 모바일(mobile) 사용자의 클러스터(cluster) 기반 상향링크 협동 다이버시티(cooperative diversity) 기법을 제안한다. 제안된 기법은 하나의 단일 안테나(single antenna) 방송 기지국과 다수의 단일 안테나 모바일 사용자가 있는 상향링크 시분할다중접속 (TDMA: Time Division Multiple Access) 시스템에서 데이터 지연허용(delay-tolerant)에 따라 클러스터를 구성하고 제곱 다이버시티 차수(square diversity order)의 협동 프로토콜(cooperative protocol)을 통해 높은 공간다이버시티 이득(spatial diversity gain)을 얻는다. 또한, 비대칭(asymmetric) 무선 채널 환경에서 공정성(fairness)을 보장한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7A
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• pp.628-638
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• 2005

The analysis of maximum diversity order and coding gain for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems over time-and frequency-selective (or doubly-selective) channels is addressed in this paper. A novel channel time-space correlation function is developed given the spatially correlated doubly-selective Rayleigh fading channel model. Based on this channel-model assumption, the upper-bound of pairwise error probability (PEP) for MIMO-OFDM systems is derived under the maximum likelihood (ML) detection. For a certain space-frequency code, we quantify the maximum diversity order and deduce the expression of coding gain. In this wort the impact of channel time selectivity is especially studied and a new definition of time diversity is illustrated correspondingly

• Proceedings of the Korean Society for Language and Information Conference
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• 2007.11a
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• pp.459-470
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• 2007

This study explores the textual characteristics, more precisely the quantity and diversity of nouns, of Japanese prime ministers' Diet addresses. In the field of stylistics, textual characteristics independent of the content have been examined with the aim on detecting the authors, genres, and chronological variations of texts. This study focuses instead on textual characteristics related to the content of texts, namely the quantity and diversity of nouns, because our aim is to analyze texts to better understand two political phenomena: (a) the difference between the two types of Diet addresses delivered by Japanese prime ministers, and (b) the perceived changes made to these addresses by two powerful prime ministers. It is a case study of the microscopic characterization of texts, which has become more and more important with the expansion in the scope of stylistics and the production of a wide variety of new types of texts following the advent of the Web.