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Analytical evaluation and experimental validation on dynamic rocking behavior for shallow foundation considering structural response

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 37-51页

作者： kil-Wan Ko Jeong-Gon ha Dong-Soo Kim Department of Civil and Environmental Engineering UC BerkeleyCalifornia 94720USA Advanced Structures and Seismic Safety Research Division Daejeon 34057Korea Department of Civil and Environmental Engineering KAISTDaejeon 34141Korea

The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong *** this study,the dynamic rocking behavior for a shallow foundation considering structural response was evaluated through two analytical approaches:the conventional soil-foundation-structure interaction(SFSI)governing equation of a single-degree-of-freedom(SDOF)structure on a rocking shallow foundation,and the Housner rocking model(i.e.,a rocking rigid block on a rigid base).Both approaches were validated with dynamic centrifuge *** test models consisted of a soft soil deposit,a shallow rectangular foundation,and an SDOF structure dominated by a bending behavior.A total of 11 foundation-structure systems and six seismic waves,including recorded earthquake signals and sinusoidal waves,were *** results showed that the conventional SFSI equation well predicted the maximum rotation during strong ***,this method was less accurate regarding the rotational phase information and maximum rotation of the foundation during weak *** the other hand,although the modified Housner′s rocking model required five parameters relevant to a soil-foundation-structure system,it overestimated the maximum rotation of the foundation when compared with the results from dynamic centrifuge tests.

关键词： soil-foundation-structure interaction maximum rotation angle rocking foundation Housner rocking model dynamic centrifuge test

Bifurcation Analysis of the Voltage Controlled Photosensitive Chaotic Oscillator

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Chinese Physics Letters 2013年第6期30卷 42-45页

作者： Van ha Nguyen han jung Song Department of Nano Systems Engineering Inje UniversityGimhae 621-749Korea Center for Nano Manufacturing Inje UniversityGimhae 621-749Korea

A photosensitive chaotic oscillator which can be controlled with light illumination under various control voltage levels is *** oscillator consists of a photodiode for the light input,clock switches and capacitors for the sample and hold function,a nonlinear function that creates an adjustable chaos map,and a voltage shifter that adjusts the output voltage for *** optimizing the photodiode sub-circuit by using an available photodiode model in PC-based simulation program with integrated circuit emphasis to obtain a suitable output,the full chaotic circuit is verified with standard 0.6-μm complementary metal oxide semiconductor *** dynamics are analyzed as a function of the light intensity under different control voltage *** time series,frequency spectra,transitions in state spaces,bifurcation diagrams and the largest Lyapunov exponent are improved.

关键词： oscillator chaotic function

On the global existence of weak solutions for the Cucker-Smale-Navier-Stokes system with shear thickening

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Science China Mathematics 2018年第11期61卷 2033-2052页

作者： Seung-Yeal ha Hwa kil Kim Jae-Myoung Kim Jinyeong Park Department of Mathematical Sciences and Research Institute of Mathematics Seoul National University Seoul 08826 Republic of Korea Korea Institute for Advanced Study Seoul 02455 Republic of Korea Department of Mathematics Education Hannam University Daejeon 34430 Republic of Korea Department of Mathematical Sciences Seoul National University Seoul 08826 Republic of Korea Department of Mathematics and Research Institute of Natural Sciences Hanyang University Seoul 04763 Republic of Korea

We study the large-time dynamics of Cucker-Smale(C-S)flocking particles interacting with nonNewtonian incompressible *** of particles and fluids were modeled using the kinetic Cucker-Smale equation for particles and non-Newtonian Navier-Stokes system for fluids,respectively and these two systems are coupled via the drag force,which is the main flocking(alignment)mechanism between particles and *** present a global existence theory for weak solutions to the coupled Cucker-Smale-Navier-Stokes system with shear *** also use a Lyapunov functional approach to show that sufficiently regular solutions approach flocking states exponentially fast in time.

关键词： emergence flocking Cucker-Smale model Navier-Stokes equation non-Newtonian fluid

Oxidative coupling of methane over LaAlO3 perovskite catalysts prepared by a co-precipitation method: Effect of co-precipitation pH value

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Journal of Energy Chemistry 2019年第8期28卷 1-8,I0001页

作者： Yujin Sim Jihoon Yoo Jeong-Myeong ha Ji Chul jung Department of Chemical Engineering Myongji UniversityYongin 17058 Republic of Korea Clean Energy Research Center Korea Institute of Science and TechnologySeoul 02792 Republic of Korea

Oxidative coupling of methane(OCM) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 *** the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCM reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCM.

关键词： LaAlO3 Perovskite Oxidative coupling of methane Co-precipitation pH value

A Comparison of GPS- and NWP-derived PW Data over the Korean Peninsula

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Advances in Atmospheric Sciences 2010年第4期27卷 871-882页

作者： ha-Taek KWON Eui-Hyun jung Gyu-Ho LIM School of Earth and Environmental Sciences Seoul National University Seoul 151-172 Korea

Precipitable Water （PW） derived from Global Positioning System （GPS） measurements and numerical weather prediction （NWP） model analysis data were compared to further evaluate the effcacy of applying GPS-derived PW to the NWP model. The spatial and temporal variations of GPS-derived PW during a rainfall event were also examined. GPS-derived PW measurements show good agreement with the behavior of water vapor at a high spatial resolution during the analysis period. Temporal anomalies of GPS-derived PW moving along with the front are successfully detected by the GPS array. Large positive anomalies of GPS-derived PW are indicated immediately before a rainfall event, and the intensity of these positive anomalies do not seem to decrease significantly as the precipitation system passes. These results indicate that the Korean GPS network may have great potential as a PW sensor over the Korean Peninsula. In contrast with GPS-derived PW, NWP-derived PW shows negative biases. These biases appear to stem mainly from the differences between modeled and actual GPS site elevations, as GPS sites were generally located at elevations lower than those employed by the NWP model. However, there still exists a discernable dry bias after a PW correction is applied to NWP-derived PW. GPS-derived PW better reflects the spatial and temporal moisture variations of precipitation systems, as compared to NWP-derived PW. These results provide entirely new information for improving the regional NWP system, since GPS-derived PW produced with data from the Korean GPS network may be incorporated into the NWP model to improve rainfall forecasts.

关键词： GPS precipitable water numerical weather prediction model dry bias

Study on SCR De NO_x mechanism through in situ electrical conductivity measurements on V_2O_5-WO_3/TiO_2 catalysts

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Rare Metals 2006年第z2期25卷 77-83页

作者： ha Heon Phil jung Soon Hyo LEE Jun Yub HONG Sung Ho Metal Processing Research Center Korea Institute of Science and Technology Cheongryang Seoul 130-650 Republic of Korea Power Engineering Research Institute Korea Power Engineering Company Inc. 360-9 Mabuk-ri Guseong-eup Yongin-si Gyeonggi-do 449-713 Republic of Korea

V2O5-WO3/TiO2 catalysts were prepared by impregnation method and in situ electrical conductivity measurements were carried out to investigate the reaction mechanism for ammonia SCR (selective catalytic reduction) of NOx. The electrical conductivity change with ammonia supply and the increase of electrical conductivity were mainly caused by reduction of the labile surface oxygen. The electrical conductivity change of catalysts shows close relationship with the conversion rate of NOx. Variation of conversion rate in atmosphere without gaseous oxygen also supports that the labile lattice oxygen is indispensable in the initial stage of the de NOx reaction. These results suggest that the liable lattice oxygen acts decisive role in the de NOx mechanism. They also support that De NOx reaction occurs through the Eley-Rideal type mechanism. The amount of labile oxygen can be estimated from the measurement of electrical conductivity change for catalysts with ammonia supply.

关键词： De NOx selective catalytic reduction electrical conductivity lattice oxygen

Combined Insights from Leachate Structure and Microstructure Characteristics for Eating Quality of Convenience Rice Processed by Super-Heated and Pressurized Steam Technologies

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Rice science 2024年第4期31卷 475-488,I0035,I0036页

作者： Mingyo ha Hyo-Young JEONG Ju Hun LEE Hyun-jung CHUNG Division of Food and Nutrition Chonnam National UniversityGwangju 61186South Korea Department of Biotechnology College of Life Sciences and BiotechnologyKorea UniversitySeoul 02841South Korea Division of Food Science&Culinary Arts Shinhan UniversityGyeonggi 11644South Korea

Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using novel processing technologies: super-heated steaming(SHS), auto-electric cooking(AEC), and pressurized-steam cooking(PSC). Additionally, the effect of two different target water contents(58% and 63%) was also evaluated. The PSC_63% sample had the highest total solids and amylopectin amount in the leachate. The amylopectin amount in the leachate differed significantly based on the targeted water content. Morphological characterization revealed that the swelling of starch and the coated layer on the surface of rice grains were most pronounced in the PSC_63% sample due to the pressure processing. The textural hardness of the AEC_58% sample was much higher than that of the other samples. The PSC_63% sample had the highest textural adhesiveness value, which can be attributed to the highest amylopectin amount in the leachate. Sensory characterization showed that the PSC_63% sample had the highest glossiness, whiteness, moistness, and overall acceptability. The principal component analysis score plots presented substantial differences in the leachate and textural and sensory characteristics of reheated convenience rice among the different processing technologies.

关键词： reheated convenience rice starch structure leachate multi-scale structure eating quality processing technology

Development and characterization of novel polymorphic microsatellite markers for the Korean freshwater snail Semisulcospira coreana and cross-species amplification using next-generation sequencing

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Journal of Oceanology and Limnology 2020年第2期38卷 503-508页

作者： Yeon jung PARK Mi Nan LEE Eun-Mi KIM jung Youn PARK Jae Koo NOH Tae-Jin CHOI jung-ha KANG Biotechnology Research Division National Institute of Fisheries ScienceBusan 46083Republic of Korea Department of Microbiology Pukyoung National UniversityBusan 48513Republic of Korea

Korean freshwater snails of the genus Semisulcospira are widely distributed across East *** has been a very popular nutritional food in Korea,and is an ecologically important water quality indicator because it lives only in clean ***,no microsatellite markers have been generated to study the population genetic diversity of this *** the present study,we developed and characterized 18 novel microsatellite loci from Semisulcospira coreana genomic *** microsatellites were isolated using 454 GS-FLX titanium sequencing and 18 markers were used for genotyping in *** addition,we also tested the cross-species transferability of the microsatellite markers in four additional Semisulcospira *** identified 18 polymorphic loci and the number of alleles per loci,and their polymorphism information content values ranged from 2 to 17 and 0.203 to 0.902,*** observed and expected heterozygosities of the loci ranged from 0.063 to 0.924 and 0.226 to 0.924,*** to the analysis of the cross-species transferability of these markers,four species,***,***,***,and ***,showed a very high transferability(80%–85%).These results show that this set of nuclear markers could be useful for population genetics studies of this species and closely related species.

关键词： Semisulcospira next-generation sequencing(NGS) microsatellite markers cross-species transferability

Colon transit time according to physical activity and characteristics in South Korean adults

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World Journal of Gastroenterology 2013年第4期19卷 550-555页

作者： Kang Ok Cho Yun Ju Jo Bong kil Song jung Woo Oh Yeon Soo Kim Institute of Korea Exercise and Development Seoul 151-877South Korea Y Department of Internal Medicine Eulji Universitiy School of MedicineSeoul 139-711South Korea Health and Exercise Science Laboratory Institute of Sports ScienceSeoul National UniversitySeoul 151-742South Korea

AIM:To investigate factors contributing to the colon transit time(CTT),physical activity and characteristics were ***:Forty-seven Korean adults(males,n=23;females,n=24) took a capsule containing 20 radioopaque markers to measure the *** subjects used an accelerometer to measure the physical activity and underwent a bioelectrical impedance analysis to determine the physical ***-nutrient was also ***:The mean total CTTs(TCTT) in the males and females were 8.8 and 24.7 h(P=0.002),*** the male subjects,the right CTT(3.5±4.9 h vs 10.0±11.6 h,P=0.023) and recto-sigmoid CTT(4.4±4.7 vs 13.6±12.5 h,P=0.004) were significantly shorter and the total energy expenditure(637.6±44.3 kcal vs 464.3±64.9 kcal,P=0.003),total activity count(247 017±75 022 count vs 178 014±75 998 count,P=0.003),energy expenditure of light intensity(148.5±6.9 kcal vs 120.0±16.8 kcal,P=0.006),energy expenditure of moderate intensity(472.0±36.2 kcal vs 281.4±22.2 kcal,P han in the female *** correlations,when adjusted for gender,fiber(r =-0.545,P < 0.001) and water intake(r =-0.257,P < 0.05) correlated significantly with the TCTT in all *** addition,the body mass index(r =-0.424,P < 0.05) and fiber intake(r =-0.417,P < 0.05) in the males as well as the fiber intake(r =-0.655,P < 0.001) in the females showed significant correlations with the ***:The subjects showed significant gender differences in the TCTT,right CTT,and recto-sigmoid ***,the intake of the fiber and water contributed to the CTT.

关键词： Colon transit time Physical activity Characteristics Macro-nutrient South Korean