• Journal of Microbiology and Biotechnology
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• 제24권11호
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• pp.1566-1573
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• 2014

Although most algae cultivation systems are operated in suspended culture, an attached growth system can offer several advantages over suspended systems. Algal cultivation becomes light-limited as the microalgal concentration increases in the suspended system; on the other hand, sunlight penetrates deeper and stronger in attached systems owing to the more transparent water. Such higher availability of sunlight makes it possible to operate a raceway pond deeper than usual, resulting in a higher areal productivity. The attached system achieved 2.8-times higher biomass productivity and total lipid productivity of $9.1g\;m^{-2}day^{-1}$ and $1.9g\;m^{-2}day^{-1}$, respectively, than the suspended system. Biomass productivity can be further increased by optimization of the culture conditions. Moreover, algal biomass harvesting and dewatering were made simpler and cheaper in attached systems, because mesh-type substrates with attached microalgae were easily removed from the culture and the remaining treated wastewater could be discharged directly. When the algal biomass was dewatered using natural sunlight, the palmitic acid (C16:0) content increased by 16% compared with the freeze-drying method. There was no great difference in other fatty acid composition. Therefore, the attached system for algal cultivation is a promising cultivation system for mass biodiesel production.

• 상하수도학회지
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• 제26권2호
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• pp.209-218
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• 2012

Recently, as reinforced water quality standards for wastewater has been announced, more efficient and more powerful wastewater treatment processes are required rather than the existing activated sludge process. In order to meet this demands, we evaluate Task 1-4 about lab scale $A_{2}O$　process using biofilm media. Task 1, 2, and 3 use 'Module A' which has 4 partitions (Anoxic/Anerobic/Oxic/Oxic). Task 4 uses 'Module B' which has 2 partitions including a denitrification reactor with an Inclined plug flow reactor (IPFR) and a nitrification reactor with biofilm media. The denitrification reactor of Module B is designed to be upward flow using IPFR. The result of evaluating at each Task has shown that attached growth system has better capacity of removal efficiency for organic matter and nitrogen with the exception of phosphorus.　Task 4 which has the most outstanding removal efficiency has 90.5% of $BOD_{5}$ removal efficiency, 97.8% of ${NH_4}^{+}-N$ removal efficiency, 65% of T-N removal efficiency and 92% of T-P removal efficiency with additional chemical phosphorus removal system operated at HRT 9hr, Qi:Qir 1:2, and BOD/T-N ratio 2.7.

• ETRI Journal
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• 제36권3호
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• pp.450-459
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• 2014

In this paper, we present a new, easy-to-generate system that is capable of creating virtual 3D tree models and simulating a variety of growth processes of a tree from a single, real tree image. We not only construct various tree models with the same trunk through our proposed digital image matting method and skeleton-based abstraction of branches, but we also animate the visual growth of the constructed 3D tree model through usage of the branch age information combined with a scaling factor. To control the simulation of a tree growth process, we consider tree-growing attributes, such as branching orders, branch width, tree size, and branch self-bending effect, at the same time. Other invisible branches and leaves are automatically attached to the tree by employing parametric branch libraries under the conventional procedural assumption of structure having a local self-similarity. Simulations with a real image confirm that our system makes it possible to achieve realistic tree models and growth processes with ease.

• 융복합기술연구소 논문집
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• 제4권1호
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• pp.1-4
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• 2014

This study was experimentally performed to show the growth characteristics of one specified plant with various liquids, which can be purchased easily. To do that, this study measured the number of leaves attached to the plant sample and the height of liquids everyday during almost 15 days on summer season in the laboratory room. From the experiments, we revealed that the remained number of leaves can be related with the liquid height.

• 한국해양공학회지
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• 제12권1호
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• pp.39-49
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• 1998

In this work, fatigue tests by axial loading were carried out to investigate the effect of stress ratio on the growth behaviors of surface fatigue crack for SM45C steel and Al 2024-T4 alloy. The growth behaviors of surface crack have been monitored during fatigue process by measuring system attached CCTV and monitor. When the growth rates of surface crack were investigate by the concept of LEFM based on Newman-Raju's .DELTA.K, the dependence of stress ratio appears both SM45C steel and Al 2024-T4 alloy. Therefore, modified stress intensity factor range, .DELTA.K' [=(1+R)/sup n/.DELTA.K] are intorduced to eliminate the dependence of stress ratio. Using .DELTA.K', it is found that the dependence of stress ratio disappears both SM45C steel and Al 2024-T4 alloy.

• 한국작물학회지
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• 제37권1호
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• pp.16-21
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• 1992

초다 근류착생성 콩 nts 382 및 nts 246와 wild-type인 Bragg의 초기생육, 뿌리혹 형성 및 질소고정능력을 조사하였으며, 그 결과는 다음과 같이 요약된다. 1. nts 계통은 뿌리혹건물중이 현저히 높아서 파종후 31일째에는 Bragg에 비하여 2.5내지 3.5배에 달하였다. 2. nts 계통은 과도한 뿌리혹 형성 때문에 지상부 광합성산물을 많이 소모하여 지상부의 생육이 저해되었다.

• 한국세라믹학회지
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• 제29권7호
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• pp.539-543
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• 1992

The continuous growth method was developed for Mn-Zn Ferrite single crystals. It is a new process that the polycrystalline MnχZn1-χFe2O4 raw materials are supplied continuously from the powder feeding system to the crucible heated by R.F. induction and melted in the crucible, and after the single crystals seed is attached to crucible's hole, the crystals are pulled downward with rotation. Growing the crystals by using the growth method different from the conventional Bridgman or Floating Zone method, we defined the factors having effect on the crystal growing through the pre-experiments. They are temperature distribution in the crucible, melt velocity according to its height, wettability between the crucible's bottom and melt. Therefore, Mn-Zn Ferrite single crystals were to be grown by attaining the appropriate melt height in the crucible, powder feeding rate, temperature gradient between the crucible and interface, crystal growing speed, and this method was confirmed to have possibility for single crystal growing.

• 한국작물학회지
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• 제49권3호
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• pp.179-183
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• 2004

호남지역 보리 2모작 재배농가의 생력화를 위하여 벼 수확 동시 보리파종에 따른 보리의 생육특성 및 생력효과를 조사ㆍ분석한 결과를 요약하면 다음과 같다. 1 벼 수확동시 보리파종은 벼 수확과 동시에 이루어지므로 관행 파종방법보다 5일 이상 빠르게 파종되었다. 2. 벼 수확동시 보리파종재배는 한발시 볏짚피복에 따른 재해 경감효과가 있었으며, 보리수확기 볏짚 C/N율은 31.6％로 낮아졌다. 3. 벼 수확동시 보리파종시 생육특성은 관행재배보다 수수는 감소하였으나 간장, 1수립수 및 천립중 등이 증가하였으며, 수량은 관행 재배보다 평균 6.5％ 증수하는 경향이었다. 4. 벼 수확동시 보리파종 작업시간은 파종작업 단계축소로 관행파종방법보다 작업시간이 58％절감되었으며, 경영비는 8％ 절감되었고, 소득은 16％ 증가하였다.

• 한국환경과학회지
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• 제22권1호
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• pp.1-6
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• 2013

A fixed biofilm reactor system composed of anaerobic, anoxic(1), anoxic(2), aerobic(1) and aerobic(2) reactor was packed with synthetic activated ceramic (SAC) media and adopted to reduce the inhibition effect of low temperature on nitrification activities. The changes of nitrification activity at different wastewater temperature were investigated through the evaluation of temperature coefficient, volatile attached solid (VAS), specific nitrification rate and alkalinity consumption. Operating temperature was varied from 20 to $5^{\circ}C$. In this biofilm system, the specific nitrification rates of $15^{\circ}C$, $10^{\circ}C$ and $5^{\circ}C$ were 0.972, 0.859 and 0.613 when the specific nitrification rate of $20^{\circ}C$ was assumed to 1.00. Moreover the nitrification activity was also observed at $5^{\circ}C$ which is lower temperature than the critical temperature condition for the microorganism of activated sludge system. The specific amount of volatile attached solid (VAS) on media was maintained the range of 13.6-12.5 mg VAS/g media at $20{\sim}10^{\circ}C$. As the temperature was downed to $5^{\circ}C$, VAS was rapidly decreased to 10.9 mg VAS/g media and effluent suspended solids was increased from 3.2 mg/L to 12.0 mg/L due to the detachment of microorganism from SAC media. And alkalinity consumption was lower than theoretical value with 5.23 mg as $CaCO_3$/mg ${NH_4}^+$-N removal at $20^{\circ}C$. Temperature coefficient (${\Theta}$) of nitrification rate ($20^{\circ}C{\sim}5^{\circ}C$) was 1.033. Therefore, this fixed film nitrogen removal process showed superior stability for low temperature condition than conventional suspended growth process.

• Archives of Pharmacal Research
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• 제19권1호
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• pp.1-5
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• 1996

Laminated films composed of drug-containing reservoir layer and drug-free membrane were prepared. Zero-order drug release with lag time was achieved by laminating drug-free film onto the reservoir layer, while burst effect was observed on cast-on film. The rate controlling membrane was either attached to or cast directly into the reservoir. The release rate was independent on the reservoir composition but dependent on the composition of rate-controlling membrane. In growth inhibitory test of cephalexin from Eudragit RS film to Streptococcus Mutans, the disk even after release test for 72 hours showed more bacterial growth inhibition than that of control. Permeation of drug through rat skin was proportional to the HPC fraction in the film. We could control the release of cephalexin from the film by changing the fraction of Eudragit RS, HPC and DEP content. Consequently, Eudragit RS/HPC film was found to be very effective system for local delivery of drugs.