• 한국IT서비스학회지
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• 제9권2호
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• pp.151-161
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• 2010

Recently, as the era of ubiquitous has arrived, an infrastructure for the short-distance wireless communication has been extended socially, and thus a variety of services are being proposed. The Multimedia Contents Delivery System using the ZigBee, in particular, has an important stance in enlargement of a variety of services in the aspect of individual-oriented service support though Wireless Personal Area Network (WPAN). Nonetheless, the ZigBee, or the IEEE 802.15.4 Standard, has many restrictions on the Multimedia Contents Delivery System due to the low data transport rate. In order to improve the ZigBee which presents a limit on the transport rate at the IEEE 802.15.4 Standard, this thesis has designed the burst mode which is a method of transmitting a certain amount of data in block units at a high speed without any stoppage until the completion of the transmission. Also, to provide a Multimedia Contents Delivery Service with an application of the normal data transmission mode, it improved the transmission performance of the ZigBee. In addition, for the Multimedia Contents Delivery Service under the ubiquitous environment, it designed and implemented a broadcasting Multimedia Contents Delivery System based on the ZigBee to conduct a comparative analysis on the data transmission performance according to the transmission method.

• Journal of Pharmaceutical Investigation
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• 제38권6호
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• pp.373-380
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• 2008

In order to develop optimal formulation and iontophoresis condition for the transdermal delivery of levodopa, we have evaluated the effect of two permeation enhancers, ethanol and oleic acid in microemulsion, on transdermal delivery of levodopa. In vitro flux studies were performed at $33^{\circ}C$, using side-by-side diffusion cell and full thickness hairless mouse skin. Current density applied was $0.4\;mA/cm^2$ and current was off after 6 hours application. Levodopa was analysed by HPLC at 280 nm. The o/w microemulsions of oleic acid in buffer solution (pH 2.5 & 4.5) were prepared using oleic acid, Tween 80 and ethanol. The existence of microemulsion regions were investigated in pseudo-ternary phase diagrams. Contrary to our expectation, cumulative amount of levodopa transported from microemulsion (pH 2.5) for 10 hours was similar to that from aqueous solution in all delivery methods (passive, anodal and cathodal). When pH of the micro-emulsion was pH 4.5, cumulative amount of levodopa transported for 10 hours increased about 40% (anodal) to 50% (cathodal), when compared to that from aqueous solution. Flux from pH 4.5 microemulsion showed higher value than that from pH 2.5 in all delivery methods. These results seem to indicate that electroosmosis plays more dominant role than electrorepulsion in the flux of levodopa at pH 2.5. The effect of ethanol on iontophoretic flux was studied using pH 2.5 phosphate buffer solution containing 3% or 5% (v/v) ethanol. Flux enhancement was observed in passive and anodal delivery as the concentration of the ethanol increased. Without ethanol, cathodal delivery showed higher flux than anodal delivery. Anodal delivery increased the cumulative amount of levodopa transported 1.6 fold by 5% ethanol after 10 hours. However, in cathodal delivery, no flux enhancement of levodopa was observed during current application and only marginal increase in cumulative amount transported after 10 hours was observed by 5% ethanol. These results seem to be related to the decrease in dielectric constant of the medium and the lipid extraction of the ethanol, which decrease the electroosmotic flow, and thus decrease the flux. Overall, the results provide important insights into the role of electroosmosis and electrorepulsion in the transport of levodopa through skin, and provide some useful informations for optimal formulation for levodopa.

• 한국콘텐츠학회논문지
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• 제7권4호
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• pp.250-258
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• 2007

타이포그래피는 언어와 조형의 결합이다. 언어의 이해와 조형적 가치를 통한 인간 커뮤니케이션의 핵심적인 수단인 것이다. 가장 기본적인 역할인 정보의 전달과 공유에서 장애요소로 나타나는 '언어의 반작용' 현상을 극복하고자 여러 가지 기법을 도입한 연구가 시작되었고, 보다 가독성 있고 의미전달력에 있어서도 효과적인 움직이는 활자를 개발하여 보편화되기에 이르렀다. 그러나 그것은 컴퓨터 모니터나 영상화면, 그리고 휴대전화 액정 등의 영상 디지털 미디어에서는 실현이 용이하나, 전통적 정보전달 매체인 인쇄지면이나 주변 환경에서 흔히 접할 수 있는 빌보드, 사인보드 등에서는 사실상 표현이 어렵다. 이를 위한 하나의 해결 방법으로 메시지 전달력이나 가독성에서 기존의 정적인 타이포그래피보다 훨씬 강력한 소구력을 가지는 동적타이포그래피에서 표현의 핵심요소인 시 공간적 표현효과에 대응하는 시각적 의미전달 체계를 색채의 본질과 특성에서 접근하여 동적표현에 근접한 커뮤니케이션 효과를 창출하고자 한다.

• 한국인터넷방송통신학회논문지
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• 제21권6호
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• pp.57-63
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• 2021

긴급재난문자 서비스는 재난 상황에 대한 정보를 휴대폰으로 전달하는 공익 서비스이다. 휴대폰 보급률이 높은 대한민국은 긴급재난문자를 통한 재난정보 전달이 다른 정보 전달 방법 보다 높은 선호도를 갖고 있다. 하지만 문자로만 이루어져 있어 정보 취약 계층에게는 일반인들에 비해 재난정보 전달이 정상적으로 이루어지지 않고 있다. 이를 보완하기 위해서 긴급재난문자 서비스를 활용한 재난정보 전달 애플리케이션을 제안하고 연구를 진행하였다. 해당 논문과 같은 연구가 계속되어 향후 긴급재난문자는 국내외의 정보취약계층을 고려한 다양한 재난 관련 정보를 전송하는 서비스가 된다면 이를 통해 국민이 재난에 신속하고 정확한 대처를 통해 재난에 대한 피해를 감소시키는 효과를 제공할 것이다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.550-553
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• 2000

The polymeric matrices made with poly(D,L-lactide-co-glycolide) were prepared using copolymer of poly(D,L-lactide) and poly(ethylene glycol) for application of drug delivery systems. Catalyst made use of stannous actoate. Particle size were differ greatly$(435.3{\pm}11.2{\sim}2284.1{\pm}188.5)$ that nanoparticle made use of according to solvent of various kinds. Polymer could a sharp distinction with copolymerized among LE-1, LE-2 and LE-3 of PLA and PEG of content that to examine $^1H-NMR$ of copolymer make refine and reprecipitation. Drug delivery effect at PLGA nanoparticle : PLA amount more then proved highly drug delivery amount that each LE-1, LE-2, LE-3, drug and solvent was 40mg, 20mg and 10mg. Drug delivery effect proved higher 20mg that change(10mg, 20mg, 40mg) at drug feeding amount with LE-2. The first a lot of drug proved delivery. LE-3 most lactide content proved much delivery since biodegradable on PLGA copolymer result from lactide. Also biodegradable rate was highest at LE-3 much of lactide content, because influence at biodegradable effect of lactide by inclusive of soft PEG.

• 한국도서관정보학회지
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• 제29권
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• pp.27-63
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• 1998

The purpose of this study is to analyze the document delivery service(DDS) of the academic libraries and suggest its improvement model in Korea. DDS means providing copies of information requests in any format and from any source. And DDS is gaining in importance as libraries turn to 'just-in-time' access rather than 'just-in-case' collection to meet user information needs. By good fortune, rising journal subscription prices, declining financial resources, canceling some of journal subscriptions, electronic transmission technologies, and the rise of commercial document delivery services have allowed libraries to begin to deliver articles to users in a much more rapid and acceptable time frame. Therefore, the library paradigm for the 2000s must be the creation of new document delivery structures which capitalize on the access tolls and structures created by librarians during the past generations. First of all, library-based document service requires a close review of existing library-to-library delivery mechanisms, application of technology to transfer of facsimiles of materials and facilitated use of existing fee-based document sources. The ideal document delivery system would feature a transparent, seamless electronic service incorporating searching and browsing identification and marking of desired items, and transmission and fulfillment of requests. And requested items would be supplied from library collection, commercial suppliers, or other sources. But the future of DDS will succeed when physical resources, policies, personnel, and practices are organized to provide timely information delivery to users.

• 디지털콘텐츠학회 논문지
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• 제19권2호
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• pp.407-413
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• 2018

최근 사물인터넷(IoT) 기술의 발전과 함께 수많은 센서와 소형 구동장치들로 구성된 새로운 컴퓨팅 환경이 도래했다. 본 논문은 이와 같은 IoT 기반 컴퓨팅 환경에서 데이터 제공자들과 소비자들 사이에 센싱 데이터를 쉽게 공유하고 접근하도록 지원하는 공유 플랫폼으로서, 확장성있는 데이터 전송 기반구조를 제안한다. 확장성과 효율성을 제공하기 위해, 이 논문은 특히 소비자들 간의 서로 다른 QoS 요구사항을 활용하여 전송 대역폭을 효과적으로 활용한 전송 경로를 구성하는 방법을 제시한다. 전송경로 구성과 재구성 과정이 제안하는 구조의 가장 큰 오버헤드로 판단되므로, 본 논문에서는 그 비용을 산정하는 기본적인 실험을 수행하였는데, 결과는 제안된 구조의 우수한 확장성에 비해 오버헤드는 비교적 적은 것으로 확인되었다.

• Journal of Communications and Networks
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• 제15권2호
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• pp.198-206
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• 2013

Recent advances in forward error correction (FEC) coding techniques were focused on addressing the challenges of multicast and broadcast delivery. However, FEC approaches can also be used for unicast content delivery in order to solve transmission control protocol issues found in wireless networks. In this paper, we exploit the error resilient properties of Raptor codes by proposing Raptor-based content delivery protocol (RCDP) - a novel solution for reliable and bidirectional unicast communication in lossy links that can improve content delivery in situations where the wireless network is the bottleneck. RCDP has been designed, validated, optimized, and its performance has been analyzed in terms of throughput and resource efficiency. Experimental results show that RCDP is a highly efficient solution for environments characterized by high delays and packet losses making it very suitable for intelligent transport system oriented applications since it achieves significant performance improvements when compared to traditional transport layer protocols.

• 유통과학연구
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• 제21권3호
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• pp.47-60
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• 2023

Purpose: During and after Covid-19 pandemic, technology has emerged as a key factor in supporting the recovery of the economy and the rise of living standards. This study examines seven factors affecting the intention of food delivery apps usage, which include Performance Expectancy, Effort Expectancy, Social Influence, Hedonic Motivation, Price Value, and Habit, and how much influence they have on the customers' behavioral continuance of food delivery apps after Covid-19 Pandemic. Research methodology: This research is a quantitative descriptive research with 473 qualified respondents from 550 respondents collected. Besides using the UTAUT2 model (Venkatesh et al., 2012), Information Quality was added to give a better explanation for the consumers' intention towards continuance behavior using food delivery apps. The collected data is then processed using SPSS 22.0. Results: Habit factors and Information Quality factors have significant positive effects on promoting food delivery apps usage intention, which in turn influences continuance behavior. In addition, Habit factors and Information Quality factors together have an effect of 48.57% on Behavioral Intention. Conclusion: The result proves that positive habits and food information quality can increase the usage intention towards the behavioral continuance of consumers. Higher usage frequency can be improved by increasing these two factors.

• Journal of Pharmaceutical Investigation
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• 제41권4호
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• pp.197-204
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• 2011

Delivery of therapeutic protein drugs is a hot issue in the clinical application, because protein drugs have low side effects and highly therapeutic effects compared with chemical drugs. Despite their prominent advantages, protein drugs have high risk for human therapy such as their easy degradation by proteolytic enzymes, renal filtration and immune response. Over the past few decades, a large number of polysaccharides as vehicles for the protein delivery system have been developed to overcome the problems. This review presents the studies on protein delivery based on polysaccharides used as stabilizer and vehicles comprising nano- or microspheres to overcome inherent limitations of therapeutic proteins.