• Smart Media Journal
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• v.4 no.2
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• pp.55-61
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• 2015

A bandwidth-enhanced ultra-wide band (UWB) CMOS balun-LNA is implemented as a part of a software defined radio (SDR) receiver which supports multi-band and multi-standard. The proposed balun-LNA is composed of a single-to-differential converter, a differential-to-single voltage summer with inductive shunt peaking, a negative feedback network, and a differential output buffer with composite common-drain (CD) and common-source (CS) amplifiers. By feeding the single-ended output of the voltage summer to the input of the LNA through a feedback network, a wideband balun-LNA exploiting negative feedback is implemented. By adopting a source follower-based inductive shunt peaking, the proposed balun-LNA achieves a wider gain bandwidth. Two LNA design examples are presented to demonstrate the usefulness of the proposed approach. The LNA I adopts the CS amplifier with a common gate common source (CGCS) balun load as the S-to-D converter for high gain and low noise figure (NF) and the LNA II uses the differential amplifier with the ac-grounded second input terminal as the S-to-D converter for high second-order input-referred intercept point (IIP2). The 3 dB gain bandwidth of the proposed balun-LNA (LNA I) is above 5 GHz and the NF is below 4 dB from 100 MHz to 5 GHz. An average power gain of 18 dB and an IIP3 of -8 ~ -2 dBm are obtained. In simulation, IIP2 of the LNA II is at least 5 dB higher than that of the LNA I with same power consumption.

• Korean journal of communication and information
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• v.32
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• pp.75-111
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• 2006

The purpose of this study is to investigate the dependency level of news attributes on the government source and to measure up the impact of news negativity, press ideology, and the conflict level on the forementioned relationship in the context of the prime definer role of the government. The prime definer means that the official source such as the government may dominate media access and create media dependency on the issue and issue attributes. To test the research questions, the content analyses of both the government briefing materials and newspapers were conducted. Textual arguments regarding the new administrative capital were chosen for the analysis. The results showed that the government source played a prime definer role in framing issue attributes of news reporting. This prime definer role was not diminished even among the negative coverage about the chosen topic. However, press ideology and the conflict level influenced the relationship between news attributes and the government-released information in some extent.

• Journal of Broadcast Engineering
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• v.12 no.5
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• pp.423-434
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• 2007

In this study, we investigated broadcasting industry in Korea and in U.S. to find out what mostly makes the broadcasting industry competitive for the near future. One source multi use(from now on OSMU) marketing strategy is important when discussing profits of broadcasting contents. To develop a theoretical and academic framework of OSMU, 14 experts participated in focus group interview. A new meaning of OSMU is defined and 4 types of OSMU business models are developed in the study. Also, two successful examples of broadcasting contents, each from Korea and U.S., were analyzed with the models that we have developed. Lastly, we discussed how to enhance the competitiveness of broadcasting contents and industry by using the benefit-maximizing-strategies of OSMU.

• Journal of Life Science
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• v.11 no.5
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• pp.496-501
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• 2001

This study was carried out to investigate the cultural characteristics and the genetic characteristics in Lepists nuda. The mycelia cultural characteristics which include the specificity for pH, carbon source, nitrogen source and medium were studied using petridish culture and liquid media culture respectively. The genetic characteristics were also investigated using random amplified polymorphic DNA (RAPD) analysis. To find out the mycelial growth rate by various medium, mycelia was cultured for 25 days in PDA, YM, MEA, GPB and Yamanaka. The Yamanaka was superior to the other media in supporting the mycelial growth. pH6 produced the best result in the test of an optimal pH. In experiment for optimal carbon source, starch showa 46.8$\pm$1.7mm of diameter of mycelial colony as the best and for nitrogen source, yeast extract showed a good effect as well. In investigation for genetic characteristics, Lepists nuda was amplified by 7 primers among 10 primers and Pleurotus ostreatus was also amplified by 7 primers. From the RAPD analysis between species, the band patterns were different.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.228-236
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• 2015

Urbanization causes many environmental, hydrological and ecological problems such as distortion of the natural water circulation system, increase in nonpoint source pollutants in stormwater runoff, degradation of surface water quality, and damage to the ecosystem. Due to the increase in impervious surface by urbanization, developed countries apply low impact development (LID) techniques as important alternatives to reduce the impacts of urbanization. In Korea, LID techniques were employed since 2012 in order to manage nonpoint source pollutants. LID technology is a technique for removing pollutants using a variety of physical, chemical and biological mechanisms in plants, microorganisms and filter media with the reduced effluence of stormwater runoff by mimicking natural water circulation system. These LID facilities are used in a variety of filter media, but an assessment has not been carried out for the comprehensive comparison evaluation of adsorption and desorption characteristics for the pollutant removal capacity. Therefore, this study was conducted to analyze the adsorption and desorption characteristics of various filter media used in the LID facilities such as sand, gravel, bioceramic, wood chips and bottom ash etc. in reducing heavy metals(Pb, Cu). In this study, the adsorption affinity for Pb in all filter media was higher than Cu. Pseudo second order equation and Langmuir-3 isotherm are more applicable in the adsorption kinetic model and adsorption isotherm model, respectively. As a result of the desorption experiment, the filter media does not exceed KSLT which is the hazardous substance leaching limit, showing the capability of the filter media in LID. The bioceramic and woodchip as filter medias were evaluated and exhibited excellent adsorption capacity for Pb.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.6
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• pp.548-557
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• 2020

Purpose: To better understand the benefits and harms of engagement with online pediatric liver disease communities within social media. Methods: We conducted a survey of caregivers of children with liver disease participating in online pediatric liver disease communities within social media, as well as a survey of healthcare providers (e.g., physicians, surgeons, nurse coordinators) from this field to better understand the perceived benefits and harms of participation. Results: Among 138 caregivers of children with liver disease that completed the survey, 97.8% agreed social media was a good place to learn about patient experiences and 88% agreed it was a good source of general information. Among caregivers, 84.8% agreed social media helps them to better advocate for their child. While 18% agreed that the information over social media was equal to the information from their healthcare team and 19% neither agreed/disagreed, only 3% indicated they would use this information to change care without telling their provider; in contrast, among 217 healthcare providers, 55% believed social media may lead caregivers to change management without telling their team. Conclusion: Engagement with online disease-specific communities in social media yields several benefits for caregivers and, in contrast to healthcare providers' concerns, participation is unlikely to lead to problems including caregivers changing the treatment plan without first discussing these plans with their team. Openness between caregivers and medical teams about the role for social media can help to improve trust and maximize the potential benefits of engagement with these groups.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.81-88
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• 2000

The elastic wave equation is solved using the finite-difference method in 3D space to simulate the seismic wave propagation. It is based on the velocity-stress formulation of the equation of motion on a staggered grid. The nonreflecting boundary conditions are used to attenuate the wave field close to the numerical boundary. To satisfy the stress-free conditions at the free-surface boundary, a new formulation combining the zero-stress formalism with the vacuum one is applied. The effective media parameters are employed to satisfy the traction continuity condition across the media interface. With use of the moment-tensor components, the wide range of source mechanism parameters can be specified. The numerical experiments are carried out in order to test the applicability and accuracy of this scheme and to understand the fundamental features of the wave propagation under the generalized elastic media structure. Computational results show that the scheme is sufficiently accurate for modeling wave propagation in 3D elastic media and generates all the possible phases appropriately in under the given heterogeneous velocity structure. Also the characteristics of the ground motion in an sedimentary basin such as the amplification, trapping, and focusing of the elastic wave energy are well represented. These results demonstrate the use of this simulation method will be helpful for modeling the ground motion of seismological and engineering purpose like earthquake hazard assessment, seismic design, city planning, and etc..

• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.236-243
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• 2011

The digital space color of new media environment denied not only the deterministic relationship of designed color and circumjacent color but also the deduced an special elements of digital space color. Such phenomena historical perspective of Gernot Wersig, new media principle of Lev Manovich and remediation of Bolter, J.K & Grusin, R. are expressed in various new media environment across. In particular, development of digital technology is moving away from its previous space color based on scientific, statistical and quantitative perspective by using diverse variables. The following research focuses on the fundamental concept of space color by type, composition of digital space color. The paper reflects on the meaning and concept of contemporary which enables the application of digital space color system on space through advanced technology. The principle of digital space color such as multidimensional malerisch, discontinuous video, vague original and copy, irregular repetitiveness of 'copy of copy', selective color of observer, experiential color of observer, and etc. makes it possible to extract the expressed element and method of digital space color. Meanwhile, the features of digital space color such as divided field of form, non-systematized of process and collage of communication can be inferred from case analysis.

• The KIPS Transactions:PartA
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• v.11A no.7 s.91
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• pp.511-520
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• 2004

A peer-to-peer model is very useful in solving the server link bottleneck problem of a client-server model. In this work, we discuss the problems of distributing multimedia content over peer-to-peer network. We focus on two problems in peer-to-peer media content distribution systems. The first is the transmission scheduling of the media data for a multi-source streaming session. We present a sophisticated scheduling scheme called fixed-length slotted scheduling, which results in minimum buffering delay. The second problem is on the fast distribution of media content in the peer-to-peer system that is self-growing. We propose a mechanism accelerating the speed at which the system's streaming ca-pacity increases, called FAST.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.204-208
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• 1997

Aureobasidium puliulans possesses the capacity for simultaneous formation of fructosyltransferase and glucosyltransferase in various sugar media including sucrose, maltose, glucose and fructose. Among them, sucrose (300 g/1) was the most suitable carbon source for fructosyltransferase production, while fructose (100 g/1) gave the maximal production of glucosyltransferase. There existed a critical concentration for the optimal formation of enzymes in sucrose, glucose and fructose media. By contrast, no effect of maltose concentrations up to 300 g/1 was observed. The specific activity of the glucosyltransferase on maltose medium was highest during the early period of fetmentation, after which a sharp decrease occurred, whereas fructosyltransferase activity on sucrose medium maintained a nearly constant rate for a given culture period. Concomitant production of fructosyltransferase and glucosyltransferase was investigated with different combinations of lower concentrations of sucrose and maltose. Maltose supplementation in sucrose media and sucrose addition to maltose media enhanced the activity ratios of fructosyltransferase to glucosyltransferase as compared to that of non-supplemented media. Several polymers and surfactants were added in an attempt to enhance enzyme production, and supplementation of polyoxyethylene-sorbitan monolaurate (Tween 20) promoted fructosyltransferase production by 20%.