• Journal of the Korean Electrochemical Society
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• v.19 no.4
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• pp.134-140
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• 2016

An aptamer-based biosensor using a new redox indicator has been examined for the electrochemical detection of thrombin. The aptamer modified primary aliphatic amine was covalently immobilized onto poly-(5,2':5',2"-terthiophene-3'-carboxylic acid) (polyTTCA) layer. Tetrabromophenolphthalein ethyl ester (KTBPE) was interacted to aptamer and used as an electrochemical indicator. Prior to the detection, the oxidation reaction of KTBPE onto aptamer modified layer was also investigated using differential pulse voltammetry. The characterization of the final sensor (KTBPE/aptamer -polyTTCA) was performed by voltammetry, QCM, and ESCA. After binding of thrombin onto KTBPE/aptamer based sensor, the peak signal of KTBPE was gradually decreased. The sensor exhibited a dynamic range between 10.0 and 100.0 nM with the detection limit of $1.0{\pm}0.2nM$.

• KSBB Journal
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• v.14 no.1
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• pp.51-57
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• 1999

The immobilization of nitrifier consortium was carried out for the application to recirculating aquaculture system(RAS). The abilities of $NH_4^+$-N removal by immobilized nitrifier consortia prepared with boric acid treated, ethanol treated, ad freezing-thawing treated PVA beads at the concentration 15% were examined. To identify the possibility of applying the beads in the fluidized bed reactor, characteristics of beads were evaluated. The suitable bead was boric acid treated beads which had highest ammonia removal rate of 16.09 g/$m^3$/day. It took 12 days for nitrifier consortium immobilized beads to be stable for the removal of $NH_4^+$-N. Life spans of the beads were more than three months with aggressive aeration in the fluidized ed reactor when nitrifier consortia immobilized in PVA beads were used. In order to apply the nitrifier consortium immobilized beads to aquaculture facility, the continuous reactor was used for 49 days with synthetic aquacultural water containing 2 mg/L ammonia. The highest ammonia removal rate of 31.87 g/$m^3$/day was observed when hydraulic residence time was 0.6 hour(36min.).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2439-2444
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• 2011

We investigated the adsorption/desorption property of volatile organic compounds(VOC) by using activated carbon fibers(ACF) instead of activated carbon(AC) which is conventionally used. The adsorption behavior of the fixed bed and the breakthrough characteristics were also studied. As a result, ACFj showed 1.15 times higher adsorption amount as compared to AC. The breakthrough Point and adsorption amount of VOCs were decreased with the increase of temperature. In the case of AC, desorption time having 99% removal efficiency was about as minutes, but that of ACF was about 5 minutes at same condition.

• The KIPS Transactions:PartB
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• v.11B no.4
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• pp.471-476
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• 2004

Recently, provides information which is most necessary to the user the research against the web information recommendation system for the Internet shopping mall is actively being advanced. the back which it will drive in the object. In that Dynamic Web Recommendation Method Using SOM (Self-Organizing Feature Maps) has the advantages of speedy execution and simplicity but has the weak points such as the lack of explanation on models and fired weight values for each node of the output layer on the established model. The method proposed in this study solves the lack of explanation using the Bayesian reasoning method. It does not give fixed weight values for each node of the output layer. Instead, the distribution includes weight using Hybrid SOM. This study designs and implements Dynamic Web Recommendation Method Using Hybrid SOM. The result of the existing Web Information recommendation methods has proved that this study's method is an excellent solution.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2898-2903
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• 2011

Adsorption/desorption characteristics of low concentration methylethylketone(MEK) and toluene vapors in beds packed with activated carbon fibers(ACF) was investigated. Performance of ACF adsorption was characterized by the equilibrium capacity, time to reach equilibrium and desorption efficiency. Experiments were carried out to define the effect of operation variables, such as feed concentration, flow rate, moisture content and bed height. The breakthrough time was shorten with the increase of temperature, flow rate and feed concentration. In addition, an increase of packed height of adsorbents lengthen the breakthrough time. The ACF loaded with MEK and toluene was satisfactorily regenerated by programed heating. It is observed that MEK is more easily removed than toluene at below temperature of $150^{\circ}C$.

• Journal of Conservation Science
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• v.29 no.1
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• pp.35-45
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• 2013

The Clay Statues of Donggwanwangmyo Shrine (Treasure No. 142) are highly damaged physical weathering which are crack, exfoliation. Pigment of surface are discolored by chemical weathering like dust. The result of ultrasonic velocity measurement, low velocity zone was measured the lowest part of Woojanggun Statue. Deficiency condition of pigment layer was evaluated quantitatively through infrared Thermography. As a result, exfoliation part was detected at high temperature. Making techniques of the Clay statues were identified by gamma rays, infrared TV, SEM. All Clay Statues were founded on wood base and joints of wood were fixed using thin iron wires. After wood base was twisted a straw rope, it was made by clay. Clay was blended with rice straw to prevention of crack and exfoliation. The upper side of clay layer was coated with Hanji(Korean handmade paper) and cotton in order to isolate the pigment layer.

• Clean Technology
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• v.18 no.3
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• pp.312-319
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• 2012

Malachite green is used a dye but malachite green is harmful toxic substance. In this study, the adsorption characteristics of zeolite has been investigated for the adsorption of malachite green dissolved in water. The effects of initial dye concentration, contact time, pH and temperature on adsorption of malachite green by a fixed amount of zeolite have been studied in batch adsorber and fixed bed. The adsorption equilibrium data are successfully fitted to the Freundlich isotherm equation in the temperature range from 25 to $45^{\circ}C$. The estimated values of k and ${\beta}$ are 23.60-46.88, 0.225-0.347, respectively. The mechanism of the adsorption process was determined from the intraparticle diffusion model. The effects of the operation conditions of the fixed bed on the breakthrough curve were investigated. When the inlet concentration and initial flow rate of malachite green are increased, the corresponding adsorption breaktime appears to decrease. Breaktime increased with increasing bed height and length of adsorption zone showed similar patterns.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.69-72
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• 2008

The so-called Pier-Shafts system which consists of the continuous column and shaft is often used to support the highway bridge structure because of advantages in easy construction and low cost. In the earthquake region, the Pier-Shafts system undergoes large displacements and represents a nonlinear behavior under the lateral seismic loading. The soil-pile interaction should be considered for more accurate analysis of the Pier-Shafts system. In this study, a transverse response of a reinforced concrete Pier-Shafts system inside multi-layered soil medium is predicted using a finite element program which adopts an elasto-plastic interface model for the interface behavior between the shaft and the soil. Then, seismic analysis is performed to evaluate the performance of Pier-Shafts system under strong ground motion and their results are verified with experimental data.

• Journal of the Korean Magnetics Society
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• v.21 no.4
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• pp.132-135
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• 2011

The exchange bias field ($H_{EX}$) and the coercivity ($H_C$) variation and change depending on the thickness of intermediately super-soft magnetic NiFeCuMo layer with different thickness of the bottom NiFe layer were investigated. The $H_{EX}$ of triple pinned NiFe(4 nm)/NiFeCuMo($t_{NiFeCuMo}$= 1 nm)/NiFe(4 nm)/FeMn multilayer has the maximum value more less than one of single pinned NiFe(8 nm)/FeMn layer. If NiFeCuMo layer is inserted each into between the pinned and free NiFe layers, we can be used as GMR-SV device for a bio-sensor that has improved magnetic sensitivity.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.499-504
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• 2009

Erythrosine is used a food coloring, ink and dye, etc. but erithrosine is rarely used in United States due to its known hazards. The adsorption characteristics of erythrosine by granular activated carbon were investigated in the batch adsorber and the packed column. The adsorptivity of activated carbon for erythrosine were largely improved by pH control. When the pH was 11 in the sample, the erythrosine could be removed 98% of initial concentration. It was estabilished that the adsorption equilibrium of erythrosine on granular activated carbon was successfully fitted by Freundlich isotherm equation in the concentration range from 10mg/L to 1,000mg/L. The characteristics of breakthrough curve of activated carbon packed column depend on the design variables such as initial concentration, bed height, and flow rate.