• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.149-154
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• 2001

The emission characteristics, flame stability, the composition of the flame zone and temperature profile were studied experimentally. The compositions of oxydant were varied by substituting $N_2$ with $CO_2$ at the constant $O_2$ concentration. Results showed that flame became unstable due to the high heat capacity, low transport rate and strong radiation effect of $CO_2$ in comparison with those of $N_2$. The reaction zone was cooled, broadened, as the conversion ratio of $CO_2$ to $N_2$ was increased. Temperature has a large effect on the NOx emission. The concentration of NOx in flue gas decreased due to the decreased temperature of reaction zone. It was also shown that the reaction was delayed by the cooling effect. As the conversion ratio of $CO_2$ to $N_2$ was increased, the emission of CO and the higher temperature zone increased due to the decrease of reaction rate by the cooling effect.

• 천문학회지
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• 제29권spc1호
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• pp.195-196
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• 1996

We observed CO J = 2 $\to$ 1 and J = 3 $\to$ 2 lines toward several star formation regions with extremely high velocity (EHV) outflows: W3 IRS5, W28 A2, GL2591, S140, and Cepheus A. The full width of the wings are 90-235 km $s^{-1}$. Some wings show clear break of slope in the line profile implying that the nature of the EHV outflow is different from that of the high velocity outflow. We suggest that the EHV CO wing emission is tracing CO molecules in the stellar wind or jet which drives the high velocity outflow.

• 전기학회논문지
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• 제59권7호
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• pp.1302-1308
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• 2010

In this study, Zigbee Sensor Node to transmit harmful gases CO and $CO_2$ information using wireless communication within the ground and underground structures were developed. Wireless communication protocol was used Zigbee Stack included IEEE 802. 15.4 MAC protocol. For wireless transmission of detected harmful gas signal from ADC of MCU was implemented Zigbee Sensor Node that was developed protocol using Serial-Port-Profile(SPP) here. The proposed Zigbee Sensor Node was verified transmission distance from experiments. Transmission distance was into 90m in experiments. Distance experiments were measured at 10m intervals using sine & pulse wave input signal at indoors. The proposed Route Sensor Node was applied mesh routing protocol. When built up USN(Ubiquitous Sensor Network)using Route Sensor Node, transmission distance was not limited. On the experimental results, harmful gas values between direct measurements and USN measurements were consistent. The semiconductor CO sensor and N-DIR $CO_2$ sensor module as a harmful sensor was used. Therefore, the proposed Zigbee Sensor Node was verified about reliability and validity to build USN for transmission of harmful gas information.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.511-516
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• 2004

A Li$[Co_{0.17}Li_{0.28}Mn_{0.55}]O_2$ cathode compound was prepared by a simple combustion method. The X-ray diffraction pattern showed that this compound could be classified as ${\alpha} -NaFeO_2$ structure type with the lattice constants of a = 2.8405(9) ${\AA}$ and c = 14.228(4) ${\AA}$. According to XANES analysis, the oxidation state of Mn and Co ions in the compound were 4+ and 3+, respectively. During the first charge process, the irreversible voltage plateau at around 4.65 V was observed. The similar voltage-plateau was observed in the initial charge profile of other solid solution series between $Li_2MnO_3\;and\;LiMnO_2$ (M=Ni, Cr...). The first discharge capacity was 187 mAh/g and the second discharge capacity increased to 204 mAh/g. As the increase of cycling number, one smooth discharge profile was converted to two distinct sub-plateaus and the discharge capacity was slowly decreased. From the Co and Mn K-edge XANES spectra measured at different cyclic process, it can be concluded that irreversible transformation of phase is occurred during continuous cycling process.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1737-1741
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• 2008

The electrochemical and thermal stability of $LiNi_{0.8}Co_{0.16}Al_{0.04}O_2$ were studied before and after $Co_3(PO_4)_2$ coating. Different to conventional coating material such as $ZrO_2$ or AlPO4, the coating layer was not detected clearly by TEM analysis, indicating that the $Co_3(PO_4)_2$ nanoparticles effectively reacted with surface impurities such as $Li_2CO_3$. The coated sample showed similar capacity at a low C rate condition. However, the rate capability was significantly improved by the coating effect. It is associated with a decrease of impedance after coating because impedance can act as a major barrier for overall cell performances in high C rate cycling. In the DSC profile of the charged sample, exothermic peaks were shifted to high temperatures and heat generation was reduced after coating, indicating the thermal reaction between electrode and electrolyte was sucessfully suppressed by $Co_3(PO_4)_2$ nanoparticle coating.

• 천문학회보
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• 제46권2호
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• pp.68.3-69
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• 2021

We present a novel profile stacking technique based on optimal profile decomposition of a 3D spectral line data cube, and its performance test using the HI data cubes of sample galaxies from HI galaxy surveys, THINGS and LITTLE THINGS. Compared to the previous approach which aligns all the spectra of a cube using their central velocities derived from either moment analysis, single Gaussian or hermite h3 polynomial fitting, the new method makes a profile decomposition of the profiles from which an optimal number of single Gaussian components is derived for each profile. The so-called superprofile which is derived by co-adding all the aligned profiles from which the other Gaussian models are subtracted is found to have weaker wings compared to the ones constructed in a typical manner. This could be due to the reduced number of asymmetric profiles in the new method. A practical test made on the HI data cubes of the THINGS and LITTLE THINGS galaxies shows that our new method can extract more mass of kinematically cold HI components in the galaxies than the previous results. Additionally, we fit a double Gaussian model to the superprofiles whose S/N is boosted, and quantify not only their profile shapes but derive the ratio of the Gaussian model parameters, such as the intensity ratio and velocity dispersion ratio of the narrower and broader Gaussian components. We discuss how the superprofile properties of the sample galaxies are correlated with their other physical properties, including star formation rate, stellar mass, metallicity, and gas mass.

• 한국식품과학회지
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• 제27권1호
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• pp.63-67
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• 1995

닭 가공부산물의 재활용 가능성을 조사하기 위하여 부산물에 산을 첨가하여 자가분해(autolysis)시켰다. 자가분해 중 일어나는 pH와 지방산 조성변화 그리고 자가분해산물(autolysate)과 소피맥의 혼합과 혼합물 건조에 따른 일반성분과 미생물 총균수 변화를 조사하였다. 마쇄한 부산물의 초기 pH 6.52는 산 첨가 직후(5분 내) 2.75로 급격히 내려갔다가 자가분해 중 약간 증가해서 $3.06{\sim}2.92$를 유지하였다. 일반성분과 지방산 조성은 자가분해에 따른 영향을 크게 받지 않았으나 미생물 총균수와 진균수의 log CFU/g은 각각 7.45와 7.11에서 자가분해 후 3.39와 2.03으로 크게 줄어들었다. 자가분해는 닭 가공부산물의 사료자원화 가능성을 보여주었다.

• Journal of Preventive Medicine and Public Health
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• 제43권3호
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• pp.213-221
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• 2010

Objectives: Plasma lipid profiles and Apolipoprotein E (ApoE) are established risk factors for cardiovascular disease (CVD). The knowledge of lipid profile may estimate the potential victims of cardiovascular disease before its initiation and progression and offers the opportunity for primary prevention. The most common ApoE polymorphism has been found to influence plasma lipid concentrations and its correlation with CVD has been extensively investigated in the last decade. Methods: The ApoE polymorphism and its influence on plasma lipid were investigated in healthy woman workers. The information on confounding factors was obtained through a self-administered questionnaire and ApoE polymorphism was investigated using PCR. Results: The relative frequencies of alleles E2, E3 and E4 for the study population (n = 305) were 0.127, 0.750 and 0.121, respectively. ApoE polymorphism was associated with variations in plasma HDL-cholesterol lipid profile. In order to estimate the independent effects of alleles E2 and E4, as compared with E3, on lipid profile, multiple regression was performed after adjustment for confounding variables such as age, BMI, blood pressure, education status, insulin, fasting glucose, HOMA-IR, menopause. ApoE2 had a negative association with HDL cholesterol and ApoE4 had a positive association with LDL cholesterol. Conclusions: This study identified that the ApoE and CVD risk factors contribute to the lipid profiles, similar to other studies. The analysis including dietary intake and other gene in further studies may help to identify clear effects on lipid profiles as risk factor for CVD.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.276-276
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• 1996

합성한 BR-8702-2의 시험결과 원소분석에서는 이론치와 실험치가 잘 일치하였고, 구조확인을 위한 FT-IR 및 FT-NMR(H$^1$)등의 시험에서도 구조와 일치하는 결과치를 나타내었다. 합성물질의 정량법을 HPLC 및 구성원소인 P와 N을 이용한 정량법에서도 유의성있는 결과를 얻을 수 있었다. 또한 분말상태인 이 물질의 안정성은 고온 고습하에서도 양호하였으며, 각종 완충수용액에서 pH가 분해에 미치는 영향을 pH-rate profile로 나타낸 결과 pH7, 8, 9에서 안정하였고 pH8에서 k=1.3$\times$$10^{-4}$day으로 가장 안정하여 shelf life는 807일이었다. 광에 대해서도 k=5.8$\times$$10^{-4}$day로 매우 안정하였다.

• Journal of Periodontal and Implant Science
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• 제38권1호
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• pp.41-50
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• 2008

Purpose: Bone morphogenetic protein-2(BMP-2) has been shown to possess significant osteoinducitve potential. There have been attempts to overcome a limitation of mass production, and economical efficiency of BMP. The aim of this study was to produce recombinant human BMP-2(rhBMP-2) from E. coli in a large scale and evaluate its biological activity. Materials and Methods: The E.coli strain BL21(DE3) was used as a host for rhBMP-2 production. Dimerized rhBMP-2 was purified by affinity chromatography using Heparin column. To determine the physicochemical properties of the rhBMP-2 expressed in E. coli, we examined the HPLC profile and performed Western blot analysis. The effect of the purified rhBMP-2 dimer on osteoblast differentiation was examined by alkaline phosphatase (ALP) activity and representing morphological change using C2C12 cell. Results: E. coli was genetically engineered to produce rhBMP-2 in a non-active aggregated form. We have established a method which involves refolding and purifying a folded rhBMP-2 dimer from non-active aggregates. The purified rhBMP-2 homodimer was characterized by SDS-PAGE as molecular weight of about 28kDa and eluted at 34% acetonitrile, 13.27 min(retention time) in the HPLC profile and detected at Western blot. The purified rhBMP-2 dimer stimulated ALP activity and induced the transformation from myogenic differentiation to osteogenic differentiation. Conclusion: rhBMP-2 was produced in E. coli using genetic engineering. The purified rhBMP-2 dimer stimulated ALP activity and induced the osteogenic differentiation of C2C12 cells.