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Detecting changes in long-period site responses after the M_w 7.6 Chi-Chi earthquake, Taiwan, using strong motion records

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 217-228页

作者： Teng-To Yu Chi-shin Wu Youg-Sin Cheng Department of Resources Engineering Cheng Kung University (NCKU)

Temporal changes in site effects are obtained using the HVSR(horizontal-to-vertical spectral ratio) method and strong motion records after the M w 7.6 Chi-Chi earthquake, Taiwan. Seismic data recorded between 1995 and 2010 are used, comprising 3,708 data from 15 stations adjacent to the Chelungpu fault. Temporal fl uctuations are determined by analyzing the site effect variation using a time–frequency variation(TFV) diagram based on these seismic data. Stations adjacent to the fault show signifi cant disturbances in the resonance frequency at 16–26 Hz. Station TCU129 shows a 40% drop in fundamental frequency after the main shock, and a gradual return to the original state over nine years. For stations located farther from the fault zone, sudden changes in tectonic stress play a dominant role in temporal changes to the HVSR. An impact analysis of the directional factor confi rms our fi nding that the proximity of the fault to seismic stations has the most infl uence on data.

关键词： Chi-Chi earthquake horizontal-to-vertical spectral

Constructing confidence intervals of extreme rainfall quantiles using Bayesian,bootstrap,and profile likelihood approaches

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Science China(Technological Sciences) 2016年第4期59卷 573-585页

作者： CHEN Si LI YaXing shin JiYae KIM TaeWoong department of civil and environmental engineering hanyang universitySeoul 133-791Korea department of electronics&communication engineering hanyang universityAnsan 426-791Korea department of civil and environmental engineering hanyang universityAnsan 426-791Korea

Hydrological risk is highly dependent on the occurrence of extreme *** fact has led to a wide range of studies on the estimation and uncertainty analysis of the *** most cases,confidence intervals(CIs)are constructed to represent the uncertainty of the *** the accuracy of CIs depends on the asymptotic normality of the data and is questionable with limited observations in practice,a Bayesian highest posterior density(HPD)interval,bootstrap percentile interval,and profile likelihood(PL)interval have been introduced to analyze the uncertainty that does not depend on the normality ***,comparison studies to investigate their performances in terms of the accuracy and uncertainty of the estimates are *** addition,the strengths,weakness,and conditions necessary for performing each method also must be ***,in this study,test experiments with simulations from varying parent distributions and different sample sizes were ***,applications to the annual maximum rainfall(AMR)time series data in South Korea were *** districts with 38-year(1973–2010)AMR observations were fitted by the three aforementioned methods in the *** both the experimental and application results,the Bayesian method is found to provide the lowest uncertainty of the design level while the PL estimates generally have the highest accuracy but also the largest *** bootstrap estimates are usually inferior to the other two methods,but can perform adequately when the distribution model is not heavy-tailed and the sample size is *** distribution tail behavior and the sample size are clearly found to affect the estimation accuracy and *** study presents a comparative result,which can help researchers make decisions in the context of assessing extreme rainfall uncertainties.

关键词： Bayesian bootstrap profile likelihood confidence interval frequency analysis

Hyperreflective photonic crystals created by shearing colloidal dispersions at ultrahigh volume fraction

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Microsystems & Nanoengineering 2024年第1期10卷 161-173页

作者： Minji Kim Jong Bin Kim shin-Hyun Kim Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea

Colloidal crystallization serves as one of the most economic and scalable production methods for photonic ***,insufficient optical performance,nonuniformity and low reproducibility remain challenges for advanced high-value *** this study,we optimally formulate a photocurable dispersion of silica particles and apply shear flow to unify the orientation of the colloidal crystals,ensuring high optical performance and *** silica particles experience strong repulsion at ultrahigh volume fractions of 50%but demonstrate low mobility,leading to polycrystalline *** shear flow to the dispersions allows the silica particles to rearrange into larger crystalline domains with a unidirectional orientation along the *** shear-induced structural change produces absolute reflectivity at the stopband as high as 90%and a high transparency of 90%at off-resonant wavelengths with minimal diffusive ***,the strong interparticle repulsion ensures a uniform volume fraction of particles throughout the dispersion,reducing deviations in the optical *** intricately micropattern the photocurable dispersions using ***,the photonic films and patterns can be stacked to form multiple layers,displaying mixed structural colors and multiple reflectance peaks without sacrificing *** superior photonic materials hold promise for various optical applications,including optical components and anticounterfeiting patches.

关键词： properties. dispersion reflectivity

Ultracompact and high-efficiency liquid-crystalon-silicon light engines for augmented reality glasses

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Opto-Electronic Advances 2024年第10期7卷 15-26页

作者： Zhenyi Luo Yuqiang Ding Fenglin Peng Guohua wei Yun Wang shin-Tson Wu College of Optics and Photonics University of Central FloridaOrlando FL 32816USA Meta Reality Labs 9845 Willows Road NERedmondWA 98052USA

In lightweight augmented reality(AR)glasses,the light engines must be very compact while keeping a high optical efficiency to enable longtime comfortable wearing and high ambient contrast ratio.“Liquid-crystal-on-silicon(LCoS)or micro-LED,who wins?”is recently a heated debate *** LCoS system is facing tremendous challenges due to its bulky illumination systems;it often incorporates a bulky polarizing beam splitter(PBS)*** minimize the formfactor of an LCoS system,here we demonstrate an ultracompact illumination system consisting of an in-coupling prism,and a light guide plate with multiple parallelepiped extraction *** overall module volume including the illumination optics and an LCoS panel(4.4-μm pixel pitch and 1024x1024 resolution elements),but excluding the projection optics,is merely 0.25 cc(cm3).Yet,our system exhibits an excellent illuminance uniformity and an impressive optical efficiency(36%–41%for a polarized input light).Such an ultracompact and high-efficiency LCoS illumination system is expected to revolutionize the next-generation AR glasses.

关键词： liquid-crystal-on-silicon light guide plate illumination system augmented reality

Chronic liver disease is universal in children with biliary atresia living with native liver

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World Journal of Gastroenterology 2017年第43期23卷 7776-7784页

作者： Way Seah Lee Sik Yong Ong Hee wei Foo shin Yee Wong Chen Xi Kong Ru Bin Seah Ruey Terng Ng Department of Paediatrics University Malaya Medical Centre Paediatrics and Child Health Research Group University Malaya

AIM To examine the medical status of children with biliary atresia(BA) surviving with native *** In this cross-sectional review,data collected included complications of chronic liver disease(CLD)(cholangitis in the preceding 12 mo,portal hypertension,variceal bleeding,fractures,hepatopulmonary syndrome,portopulmonary hypertension) and laboratory indices(white cell and platelet counts,total bilirubin,albumin,international normalized ratio,alanine aminotransferase,aspartate aminotransferase,γ-glutamyl transpeptidase). Ideal medical outcome was defined as absence of clinical evidence of CLD or abnormal laboratory indices. RESULTS Fifty-two children [females = 32,62%; median age 7.4 years,n = 35(67%) older than 5 years] with BA(median age at surgery 60 d,range of 30 to 148 d) survived with native liver. Common complications of CLD noted were portal hypertension(40%,n = 21; 2 younger than 5 years),cholangitis(36%) and bleeding varices(25%,n = 13; 1 younger than 5 years). Fifteen(29%) had no clinical complications of CLD and three(6%) had normal laboratory indices. Ideal medical outcome was only seen in 1 patient(2%). CONCLUSION Clinical or laboratory evidence of CLD are present in 98% of children with BA living with native livers after hepatoportoenterostomy. Portal hypertension and variceal bleeding may be seen in children younger than 5 years of age,underscoring the importance of medical surveillance for complications of BA starting at a young age.

关键词： Biliary atresia Medical status Chronic liver disease

Formulation of corrosion rate of magnesium alloys using microstructural parameters

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Journal of Magnesium and Alloys 2020年第1期8卷 134-149页

作者： Ahmad Bahmani Srinivasan Arthanari Kwang Seon shin Magnesium Technology Innovation Center School of Materials Science and EngineeringSeoul National University1 Gwanak-roGwanak-guSeoul 08826Korea

Up to the date of writing this article,a quantitative analysis between corrosion rate and combined microstructural parameters including composition,grain size,and precipitations has not been ***,a literature review was carried out on these parameters to understand the quantitative effect of each one on the corrosion rate of Mg and Mg ***,using the available data in the literature and several experimental results,a new model was developed to predict the corrosion rate,through microstructural *** model suggests that by using ultra-fined grains,alloying compounds with low Volta-potential difference relative to the matrix and a low fraction of secondary phase,a very low corrosion rates of materials are achievable.

关键词： Corrosion rate Magnesium Grain size Volta-potential

Effects of Supercritical Environment on Hydrocarbon-fuel Injection

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Journal of Thermal Science 2017年第2期26卷 183-191页

作者： Bongchul shin Dohun Kim Min Son Jaye Koo Graduate School Korea Aerospace UniversityGoyangRepublic of Korea School of Aerospace and Mechanical Engineering Korea Aerospace UniversityGoyangRepublic of Korea

In this study, the effects of environment conditions on decane were investigated. Decane was injected in subcritical and supercritical ambient conditions. The visualization chamber was pressurized to 1.68 MPa by using nitrogen gas at a temperature of 653 K for subcritical ambient conditions. For supercritical ambient conditions, the visualization chamber was pressurized to 2.52 MPa by using helium at a temperature of 653 K. The decane injection in the pressurized chamber was visualized via a shadowgraph technique and gradient images were obtained by a post processing method. A large variation in density gradient was observed at jet interface in the case of subcritical injection in subcritical ambient conditions. Conversely, for supercritical injection in supercritical ambient conditions, a small density gradient was observed at the jet interface. In a manner similar to that observed in other cases, supercritical injection in subcritical ambient conditions differed from supercritical ambient conditions such as sphere shape liquid. Additionally, there were changes in the interface, and the supercritical injection core width was thicker than that in the subcritical injection. Furthermore, in cases with the same injection conditions, the change in the supercritical ambient normalized core width was smaller than the change in the subcritical ambient normalized core width owing to high specific heat at the supercritical injection and small phase change at the interface. Therefore, the interface was affected by the changing ambient condition. Given that the effect of changing the thermodynamic properties of propellants could be essential for a variable thrust rocket engine, the effects of the ambient conditions were investigated experimentally.

关键词： Decane Jet Subcritical Supercritical Visualization

Few-Shot Graph Classification with Structural-Enhanced Contrastive Learning for Graph Data Copyright Protection

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Tsinghua Science and Technology 2024年第2期29卷 605-616页

作者： Kainan Zhang DongMyung shin Daehee Seo Zhipeng Cai Department of Computer Science Georgia State UniversityAtlantaGA 30303USA LSWare Inc. Seoul 08504Republic of Korea College of Intelligence Information Engineering Sangmyung UniversitySeoul 03016Republic of Korea

Open-source licenses can promote the development of machine learning by allowing others to access,modify,and redistribute the training ***,not all open-source licenses may be appropriate for data sharing,as some may not provide adequate protections for sensitive or personal information such as social network ***,some data may be subject to legal or regulatory restrictions that limit its sharing,regardless of the licensing model ***,obtaining large amounts of labeled data can be difficult,time-consuming,or expensive in many real-world ***-shot graph classification,as one application of meta-learning in supervised graph learning,aims to classify unseen graph types by only using a small amount of labeled ***,the current graph neural network methods lack full usage of graph structures on molecular graphs and social network *** structural features are known to correlate with molecular properties in chemistry,structure information tends to be ignored with sufficient property information ***,the common binary classification task of chemical compounds is unsuitable in the few-shot setting requiring novel ***,this paper focuses on the graph classification tasks of a social network,whose complex topology has an uncertain relationship with its nodes'*** two multi-class graph datasets with large node-attribute dimensions constructed to facilitate the research,we propose a novel learning framework that integrates both meta-learning and contrastive learning to enhance the utilization of graph topological *** experiments demonstrate the competitive performance of our framework respective to other state-of-the-art methods.

关键词： few-shot learning contrastive learning data copyright protection

Holo-imprinting polarization optics with a reflective liquid crystal hologram template

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Light(Science & Applications) 2022年第3期11卷 127-135页

作者： Jianghao Xiong Qian Yang Yannanqi Li shin-Tson Wu College of Optics and Photonics University of Central FloridaOrlandoFL 32816USA

Liquid crystal polarization optics based on photoalignment technique has found pervasive applications in next-generation display platforms like virtual reality and augmented *** large-scale fabrication,however,remains a big challenge due to the high demands in small feature size,fast processing speed,and defects-free alignment quality during the photoalignment process,especially for large-angle reflective *** we propose a new concept of holo-imprinting based on non-contact replication of polarization pattern with a reflective liquid crystal hologram as a *** theoretical analysis and experimental results validate the possibility of generating a high-quality polarization pattern exploiting the self-interfering beams of reflective *** method can be extended to numerous devices,from transmissive to reflective,from small angle to large angle,and from grating,lens,to freeform *** widespread impact on the fabrication of liquid crystal polarization optics for advanced display and imaging systems is foreseeable.

关键词： optics crystal alignment