Researches on the elimination of sulfur and nitrogen oxides with catalysts and absorbents reported many problems related with elimination efficiency and complex devices. In this study, decomposition efficiency of harmful gases was investigated. It was found that the efficiency rate can be increased by moving the harmful gases together with SPCP reactor and the catalysis reactor. Calcium hydroxide(Ca(OH)2), CaO, and TiO2 were used as catalysts. Harmful air polluting gases such as SO2 were measured for the analysis of decomposition efficiency, power consumption, and voltage according to changes to the process variables including frequency, concentration, electrode material, thickness of electrode, number of electrode winding, and additives to obtain optimal process conditions and the highest decomposition efficiency. The standard sample was sulfur oxide(SO2). Harmful gases were eliminated by moving them through the plasma generated in the SPCP reactor and the Ca(OH)2 catalysis reactor. The elimination rate and products were analyzed with the gas analyzer (Ecom-AC,Germany), FT-IR(Nicolet, Magna-IR560), and GC-(Shimazu). The results of the experiment conducted to decompose and eliminate the harmful gas SO2with the Ca(OH)2 catalysis reactor and SPCP reactor show 96% decomposition efficiency at the frequency of 10 kHz. The conductivity of the standard gas increased at the frequencies higher than 20 kHz. There was a partial flow of current along the surface. As a result, the decomposition efficiency decreased. The decomposition efficiency of harmful gas SO2 by the Ca(OH)2 catalysis reactor and SPCP reactor was 96.0% under 300 ppm concentration, 10 kHz frequency, and decomposition power of 20 W. It was 4% higher than the application of the SPCP reactor alone. The highest decomposition efficiency, 98.0% was achieved at the concentration of 100 ppm.

With industrial development, energy demands continue to rise. Fossil fuels release more air pollutants to produce the same amount of energy compared with other types of fuel. The harmful exhaust gas exacerbated by the increasing uses of vehicles also makes a contribution to the worsening of air pollution. Thus there is a need for various processing methods and technologies to eliminate harmful gases such as sulfur oxides released into the air. Researches on the elimination of sulfur and nitrogen oxides with catalysts and absorbents reported many problems due to elimination efficiency and complex devices. In an attempt to supplement them, this study set out to increase the decomposition efficiency of harmful gases by moving them through the plasma generated in the SPCP reactor and the catalysis reactor specially designed and manufactured. The study used calcium hydroxide(Ca (OH)2),CaO,andTiO2 as catalysts. Harmful air polluting gases such as SO2 were measured for decomposition efficiency, power consumption, and voltage according to changes to the process variables including frequency, concentration, electrode material, thickness of electrode, number of electrode winding, and additives to obtain optimal process conditions and the highest decomposition efficiency. The standard sample was sulfur oxide(SO2). Harmful gases were eliminated by moving them through the plasma generated in the SPCP reactor and the Ca(OH)2 catalysis reactor. The elimination rate and products were analyzed with the gas analyzer (Ecom-AC,Germany), FT-IR(Nicolet, Magna-IR560), and GC-(Shimazu). The results of the experiment conducted to decompose and eliminate the harmful gas SO2with the Ca(OH)2 catalysis reactor and SPCP reactor show 96 decomposition efficiency at the frequency of 10kHz. The conductivity of the standard gas increased according to frequency at high voltage of 20 kHz or more. There was a partial flow of current along the surface. As a result, the decomposition efficiency decreased. The use of tungsten electrode resulted in the highest decomposition efficiency by the Ca(OH)2 catalysis reactor and SPCP reactor, and it was followed by the copper and aluminum electrode in the order. As for the impacts of thickness of electrode at electric discharge, the thicker the electrode was, the higher decomposition efficiency became. As for the number of electrode winding, the more it was wound, the higher decomposition efficiency became. The decomposition efficiency of harmful gas SO2 by the Ca(OH)2 catalysis reactor and SPCP reactor was 96.0% under the conditions of 300ppm concentration, 10kHz frequency, and decomposition power of 20W. It was higher than 92% when only the SPCP reactor was used. Decomposition efficiency was the highest at 98.0% when the concentration was 100ppm. As for the effects of additives to fit actual exhaust gases, the more methane (CH4) was added, the higher decomposition efficiency became over 99%. The higher the oxygen concentration was, the higher decomposition efficiency became, as well

Streptococcus mutans (S. mutans) is a facultative anaerobic bacterium mainly found in the oral cavity and is known to contribute to tooth decay and gingivitis. Recent studies on intestinal microbiota have revealed that microorganisms forming a biofilm play important roles in maintaining tissue homeostasis through their own metabolism. However, the physiological roles of oral microorganisms such as S. mutans are still unclear. In our current study, we identified that constituents released from S. mutans (CR) reduce arecoline- mediated cytotoxicity without producing toxic effects themselves. Arecoline, as a major alkaloid of areca nut, is known to mediate cytotoxicity on oral epithelial cells and induces a sustained intracellular Ca2+ ([Ca2+]i) increase that is cytotoxic. The exposure of human gingival fibroblast (HGF) cells to CR not only inhibited the sustained [Ca2+]i increase but also the initial [Ca2+]i elevation. In contrast, CR had no effects on the gene regulation mediated by arecoline. These results demonstrate that S. mutans has physiological role in reducing cytotoxicity in HGF cells and may be considered a novel pharmaceutical candidate.

In this study, the air pollutant removal such as sulfur oxides was studied. A combination of the plasma discharge in the reactor by the reaction surface discharge reactor Calcium hydroxides catalytic reactor and air pollutants, hazardous gas SOx, changes in gas concentration, change in frequency, the thickness of the electrode, kinds of electrodes and the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. The experimental results showed the removal efficiency of 98% in the decomposition of sulfur oxides removal experiment when Calcium hydroxides catalysts and the tungsten(W) electrodes were used. It was increased 3% more than if you do not have the catalytic. If added to methane gas was added the removal efficiency increased decomposition.

Two types of Tb- and Na-substituted green phosphors Ca(1-1.5x)WO4: and Ca(1-2x)WO4: weresynthesized with various x values, using a solid-state reaction. The former phosphors contained both substitutional and vacancypoint defects, while the later had only substitutional defects. X-ray diffraction results showed that the main diffraction peak,(112), was centered at 2θ=28.72o and indicated that there was no basic structural deformation caused by substitutions orvacancies. The photoluminescence emission and photoluminescence excitation spectra revealed the optical properties of trivalentterbium ions, Tb3+. Typical transitions, 5D3→7F6, 7F5, 7F4 and 5D4→7F6, 7F5, 7F4, 7F3, and cross relaxations were observed.Subtle differences in the photoluminescence of green phosphors were observed as a result of the point defects. The FT-IRspectra indicated that some of the ungerade vibrational modes had shifted positions and changed shapes, spreading out overa wide range of frequencies. This change can be attributed to the different masses of Tb3+ and Na+ ions and VCa" vacanciescompared to Ca2+ ions. The gerade normal modes of the Raman spectra exhibited subtle differences resulting from point defectsin Ca(1-1.5x)TbxWO4 and Ca(1-2x)TbxNaxWO4.

본 연구애서는 ‘후지’ 사과의 CA 저장을 실용화하기 위하여 수확시기와 일정기간 저온저장한 후 CA 환경을 설정하는 지연 CA 처리가 저장 중 내부갈변장해와 과실품질에 미치는 영향을 조사하였다. 1차 년도에 ‘후지’ 사과를 10월 22일에 수확하였을 때 밀병 발생율이 40% 였고, CA 환경 조성(O2 2.5 ± 0.5% + CO2 2.5 ± 0.5%)을 20일 지연 CA 저장하였을 때는 내부갈변이 발생하였으나, 30일 지연 CA 저장에서는 내부갈변이 발생하지 않았다. 2차 년도에는 수확시기가 늦어질수록 밀병 발생율이 높았고, 이러한 과실은 10~30일 지연 CA 처리구에서 내부갈변장해가 발생하였으나, 40일 지연 CA 처리구 에서는 내부갈변장해가 발생하지 않았다. 호흡량은 저온 저장 과실에서는 저장기간이 길어질수록 급격히 증가하였으나 지연 CA 저장에서는 호흡량이 낮게 유지되었고, 급속 CA 저장에 비해서 차이를 보이지 않았다. 에틸렌 발생량은 지연 CA 저장한 과실들이 저온저장에 비해서 낮았으나, 급속 CA 저장에 비해서는 다소 높은 발생량을 보였다. 산함량은 지연 CA 저장이 급속 CA 저장에 비해 저장기간이 길어질수록 감소하는 경향이었고, 경도는 저장 8개월 후에도 급속 CA 처리구와 지연 CA 처리구간에는 차이를 보이지 않았다.

A3-2x/3Al1-zInzO4F: Eux3+ (A=Ca, Sr, Ba, x=-0.15, z=0, 0.1) oxyfluoride phosphors were simply prepared by thesolid-state method at 1050oC in air. The phosphors had the bright red photoluminescence (PL) spectra of an A3-2x/3Al1-zInzO4Ffor Eu3+ activator. X-ray diffraction (XRD) patterns of the obtained red phosphors were exhibited for indexing peak positionsand calculating unit-cell parameters. Dynamic excitation and emission spectra of Eu3+ activated red oxyfluoride phosphors wereclearly monitored. Red and blue shifts gradually occurred in the emission spectra of Eu3+ activated A3AlO4F oxyfluoridephosphors when Sr2+ by Ca2+ and Ba2+ ions were substituted, respectively. The concentration quenching as a function of Eu3+contents in A3-2x/3AlO4F:Eu3+ (A=Ca, Sr, Ba) was measured. The interesting behaviors of defect-induced A3-2x/3Al1-zInzO4-αF1-δphosphors with Eu3+ activator are discussed based on PL spectra and CIE coordinates. Substituting In3+ into the Al3+ positionin the A3-2x/3AlO4F:Eu3+ oxyfluorides resulted in the relative intensity of the red emitted phosphors noticeably increasing byseven times.

The quality properties of peeled ginger (PG) were investigated during CA storage at different CO₂concentrations. O₂ concentration was kept constant at 5% while CO₂of 6%, 14%, 22% and 30% were used. It was found that the weight loss rate tended to decrease with an increase of CO₂. In the case of fixed 10 ℃ storage, the Lvalue and a-value of the exterior color in treatment increased more than that of control with respect to time, while the b-value of the exterior color and the cutting plane color showed no significant difference. In the exterior color, the results of PG-25 ℃ showed similar with PG-10 ℃ except b-value of the exterior color which showed not a little change. The cutting plane color did not showed significantly difference in the PG samples between 25 ℃ and 10 ℃ . Hardness of the PG during storage was found to decrease most severely at 6% of CO₂concentration regardless of storage temperature. The growth of microorganisms during storage of the PG tended to be restrained as CO₂concentration increased. However, microorganisms, when maintained at 25 ℃ storage, multiplied rapidly to 10^8 CFU/g within 4 days regardless of concentration.

Perovskite manganites such as RE1-xAxMnO3 (RE = rare earth, A = Ca, Sr, Ba) have been the subject of intense research in the last few years, ever since the discovery that these systems demonstrate colossal magnetoresistance (CMR). The CMR is usually explained with the double-exchange (DE) mechanism, and CMR materials have potential applications for magnetic switching, recording devices, and more. However, the intrinsic CMR effect is usually found under the conditions of a magnetic field of several Teslas and a narrow temperature range near the Curie temperature (Tc). This magnetic field and temperature range make practical applications impossible. Recently, another type of MR, called the low-field magnetoresistance(LFMR), has also been a research focus. This MR is typically found in polycrystalline half-metallic ferromagnets, and is associated with the spin-dependent charge transport across grain boundaries. Composites with compositions La0.7(Ca1-xSrx)0.3MnO3)]0.99/(BaTiO3)0.01 [(LCSMO)0.99/(BTO)0.01]were prepared with different Sr doping levels x by a standard ceramic technique, and their electrical transport and magnetoresistance (MR) properties were investigated. The structure and morphology of the composites were studied by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). BTO peaks could not be found in the XRD pattern because the amount of BTO in the composites was too small. As the content of x decreased, the crystal structure changed from orthorhombic to rhombohedral. This change can be explained by the fact that the crystal structure of pure LCMO is orthorhombic and the crystal structure of pure LSMO is rhombohedral. The SEM results indicate that LCSMO and BTO coexist in the composites and BTO mostly segregates at the grain boundaries of LCSMO, which are in accordance with the results of the magnetic measurements. The resistivity of all the composites was measured in the range of 90-400K at 0T, 0.5T magnetic field. The result indicates that the MR of the composites increases systematically as the Ca concentration increases, although the transition temperature Tc shifts to a lower range.

목 적: 본 연구에서는 CA(Cellulose Acetate; CA)안경테 전용 가공장비의 40,000 rpm급 고속 주축시스템에 대하여 구조설계 단계에서 안정성을 검토하였다. 방 법: 안경테 전용 주축시스템의 베어링 윤활과 예압구조 선정 및 주축계의 정/동/열적 특성 분석을 통하여 고유진동수, 최대변형, 열변위를 예측하였다. 결 과: 안경테 가공장비 주축의 윤활시스템은 최소미량급유방식인 오일-에어 방식을 채택하였으며 정동적분석 결과 안정성이 확보되었으나, 열변위량은 최대 0.135 mm로 고속 회전 시 주축 발란싱과 성능에 문제가 발생 할 것으로 예측되었다. 결 론: CA안경테 전용 가공장비의 40,000 rpm급 고속 주축시스템을 설계 단계에서부터 윤활 및 예압구조를 선정하였으며, 정동적분석을 통하여 구조안정성이 우수함을 예측하였다. 그러나 회전에 따른 열상승 및 열적변형에 취약하여 이에 대한 대책이 필요할 것으로 나타났다.

보행교통류를 주제로 다양한 연구들이 진행되었지만 초기의 보행연구는 차량의 교통류이론을 그대로 적용하여 해석하기도 하였다. 최근 보행교통류에 대한 다양한 모형들이 제시되고 있으며, 특히 CA모형은 보행교통류를 위한 시뮬레이션 모형으로 빈번하게 사용되고 있다. 대표적인 CA 모형으로 가스입자의 움직임을 이용하여 양방향의 보행교통류를 설명하기도 하였는데 초기에는 정방형의 Gas-lattice 모형이 제안되었으며 이후에 정육방 Gas-lattice 모형을 이용하여 보행자의 움직임과 회피를 묘사하기도 하였다. 하지만 이러한 모형들은 보행자의 움직임을 편의임의보행으로 가정하였기 때문에 단일방향으로의 움직임만을 설명할 수 있었다. 본 연구에서 제시된 MLPM(the Multi-Layer Pedestrian Model)은 어떤 공간에서 복수개의 기종점을 가진 경우에도 현실적인 보행자의 움직임을 설명할 수 있는 모형이다.

For the aim of low-temperature co-fired ceramic microwave components, sintering behavior and microwave properties (dielectric constant , quality factor Q, and temperature coefficient of resonant frequency ) are investigated in [BCZN] ceramics with addition of . The specimens are prepared by conventional ceramic processing technique. As the main result, it is demonstrated that the additives () show the effect of lowering of sintering temperature and improvement of microwave properties at the optimum additive content. The addition of 0.25 wt% lowers the sintering temperature to utilizing liquidphase sintering and show the microwave dielectric properties (dielectric constant = 75, quality factor = 572 GHz, temperature coefficient of resonance frequency ). The estimated microwave dielectric properties with addition (increase of , decrease of , shift of to negative values) can be explained by the observed microstrucure (sintered density, abnormal grain structure) and possibly high-permittivity (BZN) phase determined by X-ray diffraction.