• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.221-226
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• 2009

Not many years ago, people found the contemporary technology expensive and difficult to use in collaborative type of meetings. Today, with the technology advanced to high standards and accessible at cheaper price, its adaption is becoming more and more ubiquitous with wide range of applications. Today's meeting rooms are not just plain old telephone systems with microphones and speakers. Today's meeting rooms are smart and intelligent. They can identify the participants; they can provide natural view of remote participants; they can proactively manage resources for collaboration and so on. More effective collaboration is possible with deployment of devices like high-definition cameras, advanced displays, sensors, gigabit networks, trackers, pointers, and high-end audio devices. Devices alone are not enough in the meeting rooms. We need software infrastructure to manage the devices and meeting contexts. One such software infrastructure is SMeet, a Smart Meeting space, which we have developed to provide an effective multi-party remote collaboration environment. Networked display systems are used in such advanced collaboration environment for better visualization. In this paper we discuss a novel approach to control and manage networked display systems in SMeet environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4910-4916
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• 2012

Changes of low concentrated nitrogen-phosphate removal efficiency were investigated in 4 strains of marine bacteria applied to ceramic media. Marine bacteria were isolated and identified from Gwangyang bay. Growth rates and removal efficiencies of $NH_3$-N of 4 strains of marine bacteria applied to ceramic media were increased approximately 3 fold and over 30% than control group, respectively. A. hydrophila and P. diminuta had highest ${NO_3}^-$-N and phosphate removal efficiencies, respectively. This results showed that ceramic media is very nice material for improvement of nitrogen-phosphate removal efficiency and isolated marine bacteria may be useful to control nitrogen-phosphate at low concentration in field.

• Environmental Engineering Research
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• v.14 no.4
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• pp.238-242
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• 2009

This study investigated the effects of organic loading rates on simultaneous carbon and nitrogen removal in an innovative fixed-film aerobic bioreactor. The fixed-film bioreactor (FFB) was composed of a two-compartment aeration tank, in which a synthetic filamentous carrier was submerged as biofilm support media, and a settling tank which polyvinylidene media (Saran) was used as settling aid for suspended solids. Three different organic loading rates, ranging from 0.92-2.02 kg chemical oxygen demand/$m^3$/day were applied by varying hydraulic retention time (HRT). The total soluble organic carbon removal efficiencies were in the range of 90-97%. The removal efficiency of ammonia was found to be in the range of 70-84%. Total nitrogen removal efficiency was found to be in the range of 40-45%, which indicates that denitrification reactions occurred simultaneously in the attached biofilm on the fibrous media in the aeration tank. The settling performance of suspended solids was significantly improved due to the presence of Saran media in the settling compartment, even for a short HRT. The fixed-film aerobic bioreactor used in this study demonstrated efficient treatment efficiency even at higher organic loading rates and at short HRTs.

• International Journal of Computer Science & Network Security
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• v.24 no.7
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• pp.207-213
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• 2024

This study investigated the perceived usability of the Blackboard learning management system (LMS) amongst students at Umm Al-Qura University. A quantitative approach was employed to explore the potential relationship between Blackboard usability and social media platform usage. Additionally, the study aimed to identify other factors influencing perceived usability. Data were collected through a three-section questionnaire distributed electronically to a sample of students (n=544). The findings, based on System Usability Scale (SUS) scores, revealed that the overall perceived usability of Blackboard resided near the midpoint of the scale, indicating an "acceptable" level. A potential negative correlation emerged between social media usage time and perceived Blackboard usability. Students who reported lower social media usage exhibited higher SUS scores. Training on Blackboard usage demonstrably exerted a positive influence on perceived usability. Gender was not identified as a statistically significant factor. An analysis of student support methods revealed that seeking help from a friend was the most prevalent approach, followed by search engines, university technical support, and social media platforms. The findings suggest that implementing strategies to improve Blackboard usability at Umm Al-Qura University could be achieved through readily accessible training materials and the exploration of alternative support channels.

• Biomedical Science Letters
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• v.23 no.2
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• pp.64-72
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• 2017

The formation of brown colonies due to phenol oxidase activity on classic agar media containing natural material extracts of Helianthus annuus or on medium containing L-3,4-dihydroxyphenylalanine has been used to identify Cryptococcus species complex. In this study, various natural materials were used to develop a modified medium and to identify five major serotypes of Cryptococcus species complex. Serotypes A, D, and A/D were pigmented on medium using Perilla frutescens var. japonica Hara (PerJ agar) after a three-day incubation. Serotypes B and C were pigmented on PerJ agar after four- and five-day incubations, respectively. Growth time and pigmentation of the five serotypes occurred more rapidly on PerJ agar than on the other media. In addition, colony morphology, size, and pigmentation were specific by serotype. In conclusion, PerJ agar should be used in clinic settings to identify Cryptococcus species complex and its serotypes rapidly.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.41-46
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• 2006

This study was carried out to evaluate the recycled waste soils from construction site for using vegetation media. The concentrations of Cd, Pb, $Cr^{6+}$, As, Hg, Cu, Cn, organic P, TCE, and PCE were measured at recycled soil piles of an industrial waste treating company in the Metropolitan landfill area. The concentrations of polluted materials did not exceed to the standard critical levels of soil pollution in all analyzed items. The results suggested a high potential of recycling of the wastes soils for vegetation soil media. However, Cd and $Cr^{6+}$ almost reached the critical levels by the time of sampling, and it is necessary to develop a skill to lower concentrations of those pollutants. In the turfgrass test, the recycled soil did show an encouraging result as vegetation media in the early growth stage of perennial ryegrass.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.363-369
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• 2011

Total ammonia nitrogen (TAN) removal efficiencies of a sand filter (SF), polystyrene microbead filter (PF), and Kaldnes bead filter (KF) media were evaluated under ammonia loading rates of 5, 25, and 50 g $m^{-3}day^{-1}$. The volume of each filter media tested was 7 L, and the water flow rate for all filter media was 24 L/min. The specific surface areas of the SF, PF, and KF were 7,836, 3,287, and 500 $m^2/m^3$, respectively. Sand was fluidized and the other two media were trickle filtered. The volumetric TAN removal rate increased with increasing ammonia loading rate for all filter media. Mean volumetric TAN removal rates under the ammonia loading rates of 5, 25, and 50 g $m^{-3}day^{-1}$ in SF (39.3, 168.6, and 322.7 g $m^{-3}day^{-1}$, respectively) were higher than those in PF (35.0, 157.4, and 310.5 g $m^{-3}day^{-1}$, respectively) and KF (32.1, 142.5, and 288.1 g $m^{-3}day^{-1}$, respectively). These results were related to differences in the specific surface areas of the filter media. PF was the most economic media for efficiently removing TAN.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.186-188
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• 2002

This experiment was carried out to know the effect of media and agar concentrations, aeration and growth regulators on rooting and acclimatization of the shoots harvested from bioreactor culture in Rehmannia glutinosa. Half MS media with 1.2% agar improved rooting and acclimatization of shoots. Shoots were effectively acclimatized and rooted well in case of aeration by using membrane filtered vessels. Shoots acclimatized in vessel with membrane Inter were healthier and had higher ex vitro survival rate than those without membrane Inter on plug tray. Addition of paclobutrazol 0.3-0.4 mg/L, to acclimatization media enhanced shoots growth and root development.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.443-448
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• 2006

본 논문에서는 고화질 협업 환경에서 다수의 고화질 영상들을 처리하기 위한 타일드 디스플레이(tiled display)기반의 확장성있는 디스플레이 구조를 제안한다. 제안하는 구조는 대형 고화질 디스플레이를 제어하기 위한 기술과 다수의 고화질 영상을 제한된 시스템 자원을 이용하여 효율적으로 디스플레이 하기위한 기술을 다룬다. 제안된 시스템은 영상의 획득/디코딩/디스플레이와 같은 가시화를 담당하는 Scalable Visualization Consumer 로 명명된 확장형 가시화 응용을 포함한다. 제안된 기법들을 토대로 구현된 확장형 가시화 시스템의 성능을 평가하고자 한다.

• Journal of Computing Science and Engineering
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• v.9 no.3
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• pp.134-141
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• 2015

In on-demand multimedia streaming systems, streaming techniques are usually combined with proxy caching to obtain better performance. The patch streaming technique has no start-up latency inherent to it, but requires extra bandwidth to deliver the media data in patch streams. This paper proposes a proxy caching technique which aims at reducing the bandwidth cost of the patch streaming technique. The proposed approach determines media prefixes with high patching cost and caches the appropriate media prefix at the proxy/local server. Herein the scheme is evaluated using a synthetically generated media access workload and its performance is compared with that of the popularity and prefix-aware interval caching scheme (the prefix part) and with that of patch streaming with no caching. The bandwidth saving, hit ratio and concurrent number of clients are used to compare the performance, and the proposed scheme is found to perform better for different caching capacities of the proxy server.