http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
遲延行列을 이용한 時燮 確率시스템의 適應 필터 構成에 관한 硏究
徐輔爀,全舜鏞,全宗鶴 慶北大學校 1991 論文集 Vol.51 No.-
This paper presents a new adaptive filter algorithm for time-varying stochastic systems. Parameters of the objective system are identified using the Kalman kilter, in which the shift matrix method applied to construct a fine adaptive filter. The proposed filter characteristics 'are proved far better than the conventional algorithms, in which the LSQ approach is commonly used. Casestudy on sample model systems proves the usefulness and advantages of the proposed algorithm.
신경회로망을 이용한 Al 2024-T3 합금의 피로손상모델에 관한 연구
홍순혁,조석수,주원식 한국공작기계학회 2001 한국생산제조학회지 Vol.10 No.4
To estimate crack growth rate and cycle ratio uniquely, many investigators have developed various kinds of mechanical parameters and theories. But, these have produced local solution space through single parameter. Neural Networks can perform pattern classification using several input and output parameters. Fatigue damage model by neural networks was used to recognize the relation between da/dN/ N/N_f, and half-value breadth ratio B/Bo, fractal dimension D_f and fracture mechanical parameters in 2024-T3 aluminium alloy. Learned neural networks has ability to predict both crack growth rate da/dN and cycle ratio N/N_f within engineering estimated mean error(5%)
Soon Hyeok Hong(홍순혁) 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.2
Highly controllable ruthenium catalysts were developed using readily available and versatile N-vinylsulfonamides as carbene precursors. Trifluoromethanesulfonamide-based catalysts initiated ultrarapidly even at temperatures as low as -60 °C and continuously propagated rapidly, enabling the enthalpically and entropically less-favored ring-opening metathesis polymerizations of low-strained functionalized cyclopentene derivatives, some of which are not accessible with previous olefin metathesis catalysts. To our surprise, the developed catalysts facilitated the polymerization of cyclopentadiene (CPD), a feedstock that is easily and commonly obtainable through the steam cracking of naphtha, which has, to the best of our knowledge, not been previously achieved due to its low ring strain and facile dimerization even at low temperatures (below 0 °C).
( Soon Hyeok Jeon ),( Hye Jin Kim ),( Kyeong Ho Kong ),( Yong Soo Park ) 한국부식방식학회(구 한국부식학회) 2014 Corrosion Science and Technology Vol.13 No.2
Influence of annealing temperature on the microstructure and resistance to pitting corrosion of the hyper duplex stainless steel was investigated in acid and neutral chloride environments. The pitting corrosion resistance is strongly dependent on the microstructure, especially the presence of chromium nitrides (Cr2N), elemental partitioning behavior and volume fraction of ferrite phase and austenite phase. Precipitation of deleterious chromium nitrides reduces the resistance to pitting corrosion due to the formation of Cr-depleted zone. The difference of PREN (Pitting Resistance Equivalent Number) values between the ferrite and austenite phases was the smallest when solution heat-treated at 1060 oC. Based on the results of electrochemical tests and critical crevice temperature tests, the optimal annealing temperature is determined as 1060 oC.
화학 교육에서 사용되는 비유에 대한 학생들의 이해도 및 비유 사용의 제한점
권혁순 ( Hyeok Soon Kwon ),최은규 ( Eun Kyu Choi ),노태희 ( Tae Hee Noh ) 한국과학교육학회 2004 한국과학교육학회지 Vol.24 No.2
In this study, students` understanding of the analogies used for chemical concepts in science textbooks, misconceptions induced by the analogy, and the factors affecting conceptual understanding were investigated. In addition to the tests of field independency and logical thinking ability, tests of students` understanding of concepts and analogies on three states of matter, pressure-volume relation, molecular motion, and changing state depending upon energy were administered. The results revealed that half of the subjects understood the analogies differently from the textbook writers` intention and that students` conceptual understanding was significantly correlated with the degree of understanding on corresponding analogies, field independency, logical thinking ability, and prior achievement of science. The results of analyzing the direct and indirect effects of each variable on conceptual understanding showed that the direct effect of prior achievement was significant and that field independency and logical thinking ability had indirect effects through understanding of analogies and prior achievement of science. The limitations and implications of using analogies in science education were discussed on the basis of the results.
Jeon, Soon-Hyeok,Hur, Do Haeng,Kim, Hye-Jin,Park, Yong-Soo Elsevier 2015 Corrosion science Vol.90 No.-
<P><B>Abstract</B></P> <P>The addition of Ce to a base alloy reduces the total size of the deleterious phases. In particular, Ce addition to a base alloy significantly decreases the amount of sigma phase precipitated, while slightly facilitating the precipitation of chromium nitride and the chi phase. During the initial stage of aging, the preferential precipitation of chromium nitride and the chi phase seems to be closely associated with the retardation of the precipitation of the sigma phase. The addition of Ce to a base alloy retards the decrease in the intergranular corrosion resistance of the alloy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ce addition to the base alloy reduces the total amount of deleterious phases. </LI> <LI> Preferential precipitation of Cr<SUB>2</SUB>N and the <I>χ</I> phase retards the <I>σ</I> phase precipitation. </LI> <LI> Ce added alloy retards the decrease in intergranular corrosion resistance. </LI> <LI> Mechanism on the effect of Ce on deleterious phases precipitation using FIB and TEM. </LI> </UL> </P>
Jong Hyeok Kwak(곽종혁),Jae Beom Jeong(정재범),Bong Kyeong Son(손봉경),Soon Ki Sung(성순기),Seong Jin Kim(김성진),Dong Won Kang(강동원),Chan Hyeok Park(박찬혁),Hyeon Wha Im(임현화),Yu Hui Lee(이유희),Bong Sang Lee(이상봉),Dong hye 한국방사선학회 2018 한국방사선학회 논문지 Vol.12 No.2
The fractional anisotropy value of the basal ganglia fibers in the brain gray matter region was analyzed by Tract-Based Spatial Statics(TBSS) method after acquiring the diffusion tensor image to identify the presence or absence of brain white matter damage to smoking in male. As a result of measurement analysis, the fractional anisotropy measurement value was lower in smokers than non–smokers in all areas, and the FA value was statistically significant. smoking significantly affects all the anatomic micro structural changes in the brain gray matter and damages the nerve fiber tract. As a result, it can affects functional abnormalities related to the minute changes of the brain due to smoking. 흡연 유무의 남성을 대상으로 뇌 회백질의 손상 유무를 파악 할 수 있는 확산텐서영상을 검사하여 영상을 획득 한 후 Tract-Based Spatial Statics(TBSS)방법으로 뇌 회백질 부위의 기저핵 신경섬유로의 비등방도 FA(fractional anisotropy)값을 측정 분석한 결과 모든 영역에서 흡연자가 비흡연자보다 비등방성 측정값이 낮게 관찰되었으며 FA값은 통계적으로 유의하였다. 본 연구의 측정한 FA결과 값으로 추측하자면 즉, 흡연이 뇌 회백질 기저핵의 모든 해부학적 미세 구조성 변화에 크게 영향을 미치며 신경섬유로를 손상시키고 이와 관련된 기능적 이상에 영향을 준다고 할 수 있다.
Jeon, Soon-Hyeok,Kim, Soon-Tae,Lee, In-Sung,Park, Joo-Hyun,Kim, Kwang-Tae,Kim, Ji-Soo,Park, Yong-Soo The Japan Institute of Metals 2011 Materials transactions Vol.52 No.3
<P>To elucidate the thermodynamics of inclusion formation and its influence on the corrosion behavior of Cu bearing duplex stainless steels, potentiodynamic and potentiostatic polarization tests, a SEM-EDS analysis of inclusions, and thermodynamic calculations of the formation of inclusions were carried out. While the resistance to general corrosion of the noble copper contained alloy-1.5Cu in a deaerated 2 M H2SO4 was higher than that of the alloy-BASE, the resistance to pitting corrosion of copper contained alloy-1.5Cu in a deaerated 0.5 N HCl + 1N NaCl and 30 mass% NaCl was lower than that of the alloy-BASE due to an increase of interface areas between inclusions and matrix acting as preferential pit initiation sites. The thermodynamic calculation for the formation of Cr-containing oxide inclusions was in good agreement with the experimental results. [doi:10.2320/matertrans.M2010355]</P>
Jeon, Soon-Hyeok,Lee, Eun-Hee,Hur, Do Haeng Elsevier 2017 Journal of nuclear materials Vol.485 No.-
<P><B>Abstract</B></P> <P>The effect of dissolved hydrogen (DH) on the general corrosion behavior and oxide films of Alloy 690TT is investigated in simulated primary water at 330 °C. With increasing DH, the structure of oxide film significantly changed and the corrosion rate decreased. At DH = 5 cm<SUP>3</SUP>/kg H<SUB>2</SUB>O, the oxide layer was thick, and consisted of outer Ni oxide layer and inner Cr<SUB>2</SUB>O<SUB>3</SUB> layer. Under the conditions of DH = 35 and 100 cm<SUP>3</SUP>/kg H<SUB>2</SUB>O, the oxide films grew thinner and composed of outer polyhedral spinel oxide particles such as NiCr<SUB>2</SUB>O<SUB>4</SUB> or NiCrFeO<SUB>4</SUB> and an intermediate metallic Ni-rich layer, with inner Cr<SUB>2</SUB>O<SUB>3</SUB> layer. The general corrosion rate significantly decreased by about 72% as DH concentration increased from 5 to 35 cm<SUP>3</SUP>/kg H<SUB>2</SUB>O. In the range of 35–65 cm<SUP>3</SUP>/kg H<SUB>2</SUB>O, the corrosion rate slightly decreased with increasing DH concentration. However, no further changes were observed in the range of 65–100 cm<SUP>3</SUP>/kg H<SUB>2</SUB>O.</P> <P><B>Highlights</B></P> <P> <UL> <LI> DH effect on the general corrosion rate of Alloy 690TT is provided. </LI> <LI> At low DH condition, the filament-like and planer Ni oxide layers were formed. </LI> <LI> At high DH condition, the polyhedral spinel oxide particles were formed. </LI> <LI> The thickness of oxide films decreased with increasing the DH concentration. </LI> <LI> General corrosion rate decreased with an increase in the DH concentration. </LI> </UL> </P>