1,728,232 research outputs found
Ji-Su Kim
No full text학위논문(박사)--아주대학교 일반대학원 :전자공학과,2014. 8DoctoralThe current wireless networks with orthogonal frequency division multiple access (OFDMA) system gives us high speed wireless communication. With high speed, variety mobile services that have different traffic characteristics and requirements have been produced. However, the interference sensitivity of OFDMA system degrades performances of cell-edge users. In addition, the diversity of mobile services causes a channel quality asymmetry between a downlink and an uplink in OFDMA system. Unfortunately, conventional mobility management schemes have not taken account the channel quality asymmetry and the diversity of service traffic. Therefore, this dissertation presents advanced mobility schemes considering the channel quality asymmetry and the diversity of service traffic for improving service continuity and user-perceived performance.
The first proposed mobility scheme is a handover scheme considering downlink-uplink channel quality asymmetry. The proposed handover scheme determines an appropriate handover timing and handover direction according to an estimated uplink channel quality and a measured downlink channel quality. For exploiting an uplink channel quality in handover, an efficient uplink channel estimation method is also proposed. The proposed method estimates an uplink signal strength using the measured downlink signal strength and predicts an uplink interference on the basis of the interference-level information that is from neighbor base stations. To improve user-perceived performances, the proposed handover scheme adjusts weights of handover criteria according to service traffic pattern. Simulation results show that the proposed uplink estimation method can accurately compute the uplink channel quality of neighbor cells where the estimation error rate is less than 0.7%. The simulation results also show that the proposed handover scheme reduces handover-call-dropping probability by up to 69% compared to LTE-Advanced system and the proposed scheme outperforms previous studies in terms of throughput and mean opinion score (MOS). In addition, the end-to-end delay of the proposed scheme is better than that of LTE-Advanced system by 26%.
The second proposed mobility scheme is the user-centric mobility scheme that exploits multipath communication to support seamless mobility. For that, the service continuity management (SCM) protocol is newly designed. SCM has four functional blocks which are located between the application layer and the transport layer. SCM monitors quality of experience (QoE) and makes multiple sessions for one service using multiple radio adaptors in order to maintain QoE requirements. To improve the efficiency of the proposed multipath communication scheme, a high efficiency transport method is proposed. The proposed scheme sends identical packets over multiple paths to improve reliability; likewise, different packets are sent to improve throughput, simultaneously. The simulation results show that the user-centric mobility scheme enable a mobile device to reduce service interruptions during handover in heterogeneous networks. Numerical results indicate that the proposed transport scheme achieves the maximum transport control protocol (TCP) throughput when the proportion of same and different packets is adjusted according to link conditions
Byung Su Kim
No full text학위논문(석사)--아주대학교 일반대학원 :응용생명공학과,2019. 2Ⅰ. Introduction 1
Ⅱ. Materials and Methods 4
A. PF Manufacturing Methods 4
B. Identification of Antioxidant and cytotoxicity 5
1. DPPH Assay 5
2. Total Polyphenol 5
3. Total Flavonoid 6
4. MTT Assay 6
C. Wrinkle improvement experiments 7
1. Inhibition effects on collagenase activity 7
2. Inhibition effects on Elastase activity 8
D. Analysis and absorption measurements 9
1. PE4 Manufacturing Methods 9
2. Morphological analysis 11
3. Absorption force measurement 11
Ⅲ. Results and Discussion 13
Ⅳ. Conclusions 26
REFERENCES 28MasterCosmetics are changing to the concept of functional effect such as whitening, wrinkle improvement, and ultraviolet ray shielding in a basic concept that adds charm to the human body and changes the appearance brightly. In this study, the antioxidative and wrinkle - improving effects of natural materials, which have excellent antioxidative and safety properties, are investigated.
The antioxidant activity of Pueraria lobata Ohwi extracts was confirmed by DPPH assay and total polyphenol content and total flavonoid content were measured. In order to increase antioxidant activity of Pueraria lobata Ohwi extracts, Lactobacillus Fermentum MieV L1208, which was commissioned by M&C Life Science, showed the highest antioxidative effect of Pueraria lobata Ohwi extracts after the fermentation. It was confirmed that the fermented extracts of Pueraria lobata Ohwi were confirmed to have no cytotoxicity by 20% using fibroblast HDF cells, and the activities of inhibition of intracellular collagenase and elastase activity were inhibited compared to the control group.
The results of liposomalization of fermented Pueraria lobata Ohwi extracts with antioxidant activity and wrinkle - improving effect were compared with skin absorption by using Franz Diffusion Cell. The liposomalization of fermented Pueraria lobata Ohwi extracts showed increased absorption capacity.
As a result, it was confirmed that the size of liposomal Pueraria lobata Ohwi extracts was reduced to about 250 nm and it had uniform distribution. As a result of observing through electron microscope, it was found that a stable spherical shape was formed Based on the above results, it was confirmed that the fermeted Pueraria lobata Ohwi extracts showed high antioxidant ability, and it could help to improve wrinkles and skin elasticity, and the liposomized fermented Pueraria lobata Ohwi extracts is highly likely to be used as a cosmetic material having excellent efficacy
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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