检索结果-南通市图书馆

Wavelet Estimation in Heteroscedastic Model Under Censored Samples

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2007年第12期23卷 2253-2268页

作者： Han Ying LIANG Jong IL baek Department of Mathematics Tongji University Shanghai 200092 P. R. China School of Mathematics & Informational Statistics and Institute of Basic Natural Science Wonkwang University Ik-San 570-749 South Korea

Consider the heteroscedastic regression model Yi = g（xi）＋ σiei, 1 ≤ i ≤ n, where σi^2 = f（ui）, here （xi, ui） being fixed design points, g and f being unknown functions defined on [0, 1], ei being independent random errors with mean zero. Assuming that Yi are censored randomly and the censored distribution function is known or unknown, we discuss the rates of strong uniformly convergence for wavelet estimators of g and f, respectively. Also, the asymptotic normality for the wavelet estimators of g is investigated.

关键词： censored sample heteroscedastic regression model wavelet estimator strong unform convergence rate asymptotic normality

Nucleation and growth behavior of coating film on Mg–Al–Zn alloy with different surface topographies via plasma electrolytic oxidation

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2022年第8期10卷 2185-2192页

作者： Nisa Nashrah Sung Hun baek Young Gun Ko Materials Electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea

This work was made to investigate how nucleation and growth behavior of the coating film were affected by surface topographies of Mg–Al–Zn alloy substrate during the initial stage of plasma electrolytic oxidation(PEO).To satisfy this end,a single substrate was prepared by mechanical treatment exhibiting rough and smooth regions with an equal area on the *** rough region with prominent hills and grooves induced the breakdown of passive film,which was indicated by an early appearance of plasma discharge on the rough region since nucleation of coating film occurred preferentially around the ***,the coating film grown on the grooves was somewhat thicker and more porous than the film grown on the hills and smooth *** was due to the fact that the growth of the coating film was found to be localized in the presence of rough region,which was in line with the discharge ***,the nucleation and growth behavior during the initial stage of PEO will be discussed schematically on the basis of microstructural interpretation.

关键词： Mg alloy Surface roughness Plasma electrolytic oxidation Coating film

Improvement of uniformity in cultivation environment and crop growth rate by hybrid control of air flow devices

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2015年第12期22卷 4702-4708页

作者： baek Min-Seon KWON Sook-Youn LIM Jae-Hyun Department of Computer Science and Engineering Kongju National University Green Energy Technology Research Center Kongju National University

A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation ***,it has a problem of irregular crop growth due to temperature deviation at upper and lower beds and increases in energy consumption by a prolonged cultivation *** this work,air flow rate inside a facility was improved by a hybrid control of air flow devices like air conditioning and air circulation fan with an established wireless sensor network to minimize temperature deviations between upper and lower beds and to promote crop *** performance of proposed system was verified with an experimental environment or Case A wherein air conditioning device was operated without a control algorithm and Case B wherein air conditioning and circulation fans were alternatively operated based on the hybrid control *** planting leafy vegetables under each experimental condition,crops were cultivated for 21 *** a result,Case B wherein AC(air conditioning) and ACF(air-circulation fan) were alternatively operated based on the hybrid control algorithm showed that fresh mass,number of leaves,and leaf length for the crops grown were increased by 40.6%,41.1%,and 11.1%,respectively,compared to Case A.

关键词： air flow devices hybrid control cultivation environment uniformity growth rate

What is a Korean officetel？ Case study on Bundang New Town

在线全文

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2017年第2期6卷 261-271页

作者： Emilien Gohaud Seungman baek School of Architecture Yeungnam University Gyeongbuk 38541 South Korea

The purpose of this study is to identify a little-known element in Korea＇s housing typology： the officetel. A portmanteau of the English office and hotel, the officetel was originally a work facility with adjunct basic living amenities. It was introduced in the 1980s and became widespread in the 1990s and 2000s. Under heavy real estate pressure, its housing component was reinforced at the expense of polyvalent use. Legally ambiguous, the officetel converts urban zones that are officially dedicated to business activities into housing, and this conversion raises questions about the zoning system underlying Korea＇s land management. Bundang is a satellite new town of Seoul, and its development coincides with that of the officetel. With this town as a case study, we clarify the concept of the officetel and analyze the different architectural forms it has generated. We use 12 representative cases to analyze the internal structure of the officetel and its relation to the city. We demonstrate that the officete[ is a unique housing type, and its peculiar characteristics are related to its origin in office buildings. Such characteristics as high density, compactness, urban compatibility, and versa- tility should be valorized in the search for new urban housing forms in Korea.

关键词： South Korea Officetel Housing typology Multi-purpose Zoning

Effect of Ni Contents on the Microstructure and Mechanical Properties of Martensitic Stainless Steel Guide Roll by Centrifugal Casting

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2008年第3期24卷 343-346页

作者： Villando Thursdiyanto Eun-Jae Bae Eung-Ryul baek School of Materials Science and Engineering Yeungnam University

A novel process based on centrifugal casting was developed to produce martensitic stainless steel for guideroll materials. Centrifugal casting provides a lower production cost and less of the thermal cracking defects which normally occur in the overlaid welding process. In this study, the effects of Ni on the microstructure and mechanical properties of martensitic stainless steel were investigated. The results show that the addition of Ni resulted in a decrease in the volume fraction of delta ferrite and an increase in the volume fraction of the retained austenite, respectively. Moreover, a tensile strength of 1600 MPa with an elongation of 4% were obtained after tempering at 500℃ for 2 h. These values were higher than those obtained by using the conventional overlaid process.

关键词： Centrifugal casting Martensitic stainless steel Delta ferrite Mechanical properties

The Southern Annular Mode(SAM) in PMIP2 Simulations of the Last Glacial Maximum

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2014年第4期31卷 863-878页

作者： Seong-Joong KIM L Junmei baek-Min KIM Korea Polar Research Institute KORDI Chinese Academy of Meteorological Sciences

The increasing trend of the Southern Annular Mode （SAM） in recent decades has influenced climate change in the Southem Hemisphere （SH）.How the SAM will respond increased greenhouse gas concentrations in the future remains *** the variability of the SAM in the past under a colder climate such as during the Last Glacial Maximum （LGM） might provide some understanding of the response of the SAM under a future warmer *** analyzed the changes in the SAM during the LGM in comparison to pre-industrial （PI） simulations using five coupled ocean-atmosphere models （CCSM,FGOALS,IPSL,MIROC,HadCM） from the second phase of the Paleoclimate Modelling Intercomparison Project （PMIP2）.In CCSM,MIROC,IPSL,and FGOALS,the variability of the simulated SAM appears to be reduced in the LGM compared to the PI simulations,with a decrease in the standard deviation of the SAM ***,four out of the five models suggest a weaker SAM amplitude in the LGM consistent with a weaker SH polar vortex and westerly winds found in some proxy records and model *** weakening of the SAM in the LGM was associated with an increase in the vertical propagation of Rossby waves in southern high latitudes.

关键词： Southern Annular Mode Last Glacial Maximum PMIP2 Southern Hemisphere westerly winds

Structural optimization for ball valve made of CF8M stainless steel

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第B09期19卷 258-261页

作者： Seung-Gyu KIM Seok-Heum baek Young-Chul PARK Department of Mechanical Engineering Dong-A University

The mechanical and chemical properties of CF8M were studied through experiments. An application of CF8M in valve body was analyzed by using finite element method(FEM) to evaluate the structural safety. An optimization containing several variables based on the response surface method(RSM) was conducted to find the optimum dimension of the valve. The results show that using this process can save valve mass as well as the computational expense effectively.

关键词：结构优化球阀不锈钢化学性能有限元法结构安全最佳尺寸 FEM

Aluminum doping for optimization of ultrathin and high-k dielectric layer based on SrTiO3

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第7期42卷 28-37页

作者： Ji-Ye baek Le Thai Duy Sang Yeon Lee Hyungtak Seo Department of Energy Systems Research Ajou UniversitySuwon 443-749South Kore Department of Materials Science and Engineering Ajou UniversitySuwon 443-749South Korea

An ultrathin SrTiO3 dielectric layer is optimized through Al doping to solve the problems existing in development of ultra-high-k oxide MOS *** post-deposition annealing,Al doping induces changes in the electronic structure of SrTiO3,thereby effectively reducing leakage current to 80) of ultrathin SrTMO3 MOS *** titanate(SrTiO3) is a high-k material but its bandgap is smaller than that of other oxide dielectrics(e.g.,SiO2,Al2 O3).Consequently,an ultrathin SrTiO3 film may have a high tunneling leakage current,which is not suitable for capacitor-based *** improve the performance of metal-oxide-semiconductor(MOS) capacitors using SrTiO3,an approach based on homogenous and uniform aluminum doping to SrTiO3 through co-sputtering is *** bandgap of a pristine SrTiO3 film showed an increase of 0.5 eV after Al ***,Al doping decreased the leakage current of SrTiO3/Si-based MOS capacitors by more than five orders of magnitude(at the level of nanoampere per square centimeter).Importantly,a dielectric constant of 81.3 and equivalent oxide thickness less than 5 A were achieved in an 8-nm-thick Al-doped SrTiO3 film owing to changes in its crystal structure and conduction band edge electronic ***,the obtained data show the effectiveness of the proposed approach for solving the problems existing in the development of ultra-high-k oxide MOS capacitors.

关键词： Aluminum doping SrTiO3 ultrathin High dielectric constant MOS capacitors

Patternable production of SrTiO_(3) nanoparticles using 1-W laser directly on flexible humidity sensor platform based on ITO/SrTiO_(3)/CNT

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第12期71卷 186-194页

作者： Le Thai Duy Ji-Ye baek Ye-Ji Mun Hyungtak Seo Department of Materials Science&Engineering Ajou UniversitySuwon16499South Korea Department of Energy Systems Research Ajou UniversitySuwon16499South Korea

Perovskite oxides like S rTiO_(3) at the nanoscale are of interest for eme rging applications,including high-k dielectrics and ***,their synthesis requires long calcination at the elevated temperature,which is a barrier of their application to flexible ***,an effective laser-assisted sol-gel method to patternably produce S rTiO_(3) na noparticles(-100 nm)in selective areas on polyimide substrates(coated with ITO)is ***,the violet-laser power is just 1 W but sufficient to crystallize the material in a short period(a few seconds).Furthermore,developing a flexible device platform using carbon nanotubes(CNT)and SrTiO_(3) nanoparticles for detection of humidity changes at room temperature is *** sensor platform has both capacitive and resistive sensing *** resistive mode with a lower power usage(about 0.2μW)is suitable for long monitoring of humidity in the range of2%RH and *** capacitive mode with higher sensitivity,faster response/recovery time(1-3 min),and lower detection limit(0.5%RH)can be used for calibration *** performance of the flexible sensor is still maintained after 5000 bending cycles at 1.5-cm ***,our synthesis method and the flexible sensor show chances for mass-producing perovskite oxides at low cost for wearable electronics.

关键词： SrTiO_(3) Nanoparticles Laser annealing Patternable Flexible sensor CNT