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Support vector machine regression(SVR)-based nonlinear modeling of radiometric transforming relation for the coarse-resolution data-referenced relative radiometric normalization(RRN)

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Geo-Spatial Information Science 2020年第3期23卷 237-247,I0004页

作者： Jing Geng Wenxia Gan Jinying Xu Ruqin Yang Shuliang Wang School of Computer Science and Technology Beijing Institute of TechnologyBeijingChina Beijing Institute of Technology BeijingChina School of Civil Engineering and Architecture Wuhan Institute of TechnologyWuhanChina Wuhan Natural Resources and Planning Information center WuhanChina

Radiometric normalization,as an essential step for multi-source and multi-temporal data processing,has received critical *** Radiometric Normalization(RRN)method has been primarily used for eliminating the radiometric *** radiometric trans-forming relation between the subject {1. and the reference {1. is an essential aspect of *** at accurate radiometric transforming relation modeling,the learning-based nonlinear regression method,Support Vector machine Regression(SVR)is used for fitting the complicated radiometric transforming relation for the coarse-resolution data-referenced *** evaluate the effectiveness of the proposed method,a series of experiments are performed,including two synthetic data experiments and one real data *** the proposed method is compared with other methods that use linear regression,Artificial Neural Network(ANN)or Random Forest(RF)for radiometric transforming relation *** results show that the proposed method performs well on fitting the radiometric transforming relation and could enhance the RRN performance.

关键词： Support Vector machine Regression(SVR) non-linear radiometric transforming relation Relative Radiometric Normalization(RRN) multi-source data

Key issues and progress of industrial big data-based intelligent blast furnace ironmaking technology

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1651-1666页

作者： Quan Shi Jue Tang Mansheng Chu School of Metallurgy Northeastern UniversityShenyang 110819China Institute for Frontier Technologies of Low-carbon Steelmaking Northeastern UniversityShenyang 110819China Engineering Research center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

Blast furnace (BF) ironmaking is the most typical “black box” process, and its complexity and uncertainty bring forth great challenges for furnace condition judgment and BF operation. Rich data resources for BF ironmaking are available, and the rapid development of data science and intelligent technology will provide an effective means to solve the uncertainty problem in the BF ironmaking process. This work focused on the application of artificial intelligence technology in BF ironmaking. The current intelligent BF ironmaking technology was summarized and analyzed from five aspects. These aspects include BF data management, the analyses of time delay and correlation, the prediction of BF key variables, the evaluation of BF status, and the multi-objective intelligent optimization of BF operations. Solutions and suggestions were offered for the problems in the current progress, and some outlooks for future prospects and technological breakthroughs were added. To effectively improve the BF data quality, we comprehensively considered the data problems and the characteristics of algorithms and selected the data processing method scientifically. For analyzing important BF characteristics, the effect of the delay was eliminated to ensure an accurate logical relationship between the BF parameters and economic indicators. As for BF parameter prediction and BF status evaluation,a BF intelligence model that integrates data information and process mechanism was built to effectively achieve the accurate prediction of BF key indexes and the scientific evaluation of BF status. During the optimization of BF parameters, low risk, low cost, and high return were used as the optimization criteria, and while pursuing the optimization effect, the feasibility and site operation cost were considered *** work will help increase the process operator’s overall awareness and understanding of intelligent BF technology. Additionally, combining big data technology with the proces

关键词： BF ironmaking intelligent BF industrial big data machine learning integrated mechanism and data

Roles of autophagy in lymphocytes： reflections and directions

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Cellular & Molecular Immunology 2010年第2期7卷 104-107页

作者： Ian X McLeod Youwen He Department of Immunology Duke University Medical Center Durham NC USA

Recent studies have revealed that autophagy, a fundamental intracellular process, plays many different roles in lymphocyte development and function. Autophagy regulates naive T-lymphocyte homeostasis, specifically by regulating mitochondrial quality and turnover, and is necessary for the proliferation of mature T cells. Autophagy also acts as a cellular death pathway in lymphocytes, both upon prolonged cytokine withdrawal and during acute antigen-receptor stimulation if improperly regulated. Furthermore, during HIV infection, hyperinduction of autophagy leads to massive T-cell death in uninfected CD4＋ T cells, and is rescued by inhibiting autophagic initiation. Constitutively high levels of autophagy in thymic epithelial cells are necessary for optimal processing and presentation of endogenous antigens, and required for proper positive and negative selection of developing thymocytes. Autophagy also promotes the survival of B lymphocytes, as well as the development of early B-cell progenitors. In B cells, autophagy is an alternative death pathway, as antigen-receptor stimulation in the absence of costimulation induces a potent autophagic death. Thus, autophagy plays a complex role in lymphocytes and is regulated during their lifespan to ensure a healthy immune system.

关键词： apoptosis autophagy homeostasis lymphocytes

Enhanced charge separation by interchain hole delocalization in nonfullerene acceptor-based bulk heterojunction materials

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Carbon Energy 2023年第7期5卷 27-37页

作者： Chang-Mok Oh Sujung Park Jihoon Lee Sung Heum Park Shinuk Cho In-Wook Hwang Advanced Photonics Research Institute Gwangju Institute of Science and TechnologyGwangjuRepublic of Korea Department of Physics and Energy Harvest Storage Research center University of UlsanUlsanRepublic of Korea Department of Physics Pukyong National UniversityBusanRepublic of Korea

Bulk heterojunction(BHJ)composites show improved power conversion efficiencies when optimized in terms of morphology using various film processing methods.A reduced carrier recombination loss in an optimized BHJ was characterized ***,the driving force that leads to this reduction was not clearly *** this study,we focus on the decreased carrier recombination loss and its driving force in optimized nonfullerene acceptor-based PTB7-Th:IEICO-4F BHJ *** demonstrate that the optimized BHJ shows deactivation in the sub-nanosecond nongeminate carrier recombination *** driving force for this deactivation was determined to be the improved interchain hole delocalization between the *** enhanced interchain hole delocalization was observed using steady-state photoinduced absorption(PIA)*** particular,increased splitting between the polaron PIA bands was ***,improved interchain hole delocalization was observed for other state-of-the-art BHJ materials,including D1.:Y6 with optimized morphologies.

关键词： bulk heterojunction interchain hole delocalization nonfullerene acceptor photoinduced absorption spectroscopy solar cell

Multi-physical Modeling and Adjusting for Ultrasonic Assisted Soft Abrasive Flow processing

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 111-124页

作者： Yesha Ni Yunfeng Tan Dapeng Tan Key Lab of E&M Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China Collaborative Innovation center of High-end Laser Manufacturing Equipment Zhejiang Province&Ministry of EducationHangzhou 310014China

The polishing efficiency of the soft abrasive flow(SAF)method is low,which is not in line with the concept of carbon emission reduction in industrial *** address the above issue,a two-phase fluid multi-physics modeling method for ultrasonic-assisted SAF processing is *** acoustics-fluid coupling mechanic model based on the realizable k-ε model and Helmholtz equation is built to analyze the cavitation *** results show that the pro-posed modeling and solution method oriented to ultrasonic-assisted SAF processing have better revealed the flow field evolution *** turbulence kinetic energy at different ultrasonic frequencies and amplitudes is *** results show that the ultrasonic vibration can induce a cavitation effect in the constrained flow chan-nel and promote the turbulence intensity and uniformity of the abrasive flow.A set of comparative polishing experiments with or without ultrasonic vibration are conducted to explore the performance of the proposed *** can be found that the ultrasonic-assisted SAF method can improve the machining efficiency and uniformity,to achieve the purpose of carbon emission *** relevant result can offer a helpful reference for the SAF method.

关键词： Soft abrasive flow Ultrasonic vibration Cavitation effect Polishing efficiency Turbulent kinetic energy

Plasmonic polarization generator in well-routed beaming

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Light(Science & Applications) 2015年第1期4卷 192-196页

作者： Lin Li Tao Li Xia-Mei Tang Shu-Ming Wang Qian-Jin Wang Shi-Ning Zhu National Laboratory of Solid State Microstructures School of PhysicsCollege of Engineering and Applied SciencesNanjing UniversityNanjing210093China Collaborative Innovation center of Advanced Microstructures Nanjing UniversityNanjing 210093China

As one of the recent advances of optics and photonics,plasmonics has enabled unprecedented optical *** a vectorial configuration of surface plasmon field,metallic nanostructures offer efficient solutions in polarization control with a very limited sample *** compact polarization devices have been realized using such metallic ***,in most of these devices,the functions were usually simple and limited to a few polarization ***,we demonstrated a plasmonic polarization generator that can reconfigure an input polarization to all types of polarization states *** plasmonic polarization generator is based on the interference of the in-plane(longitudinal)field of the surface plasmons that gives rise to versatile near-field polarization states on a metal surface,which have seldom been considered in previous *** a well-designed nanohole array,the in-plane field of SPPs with proper polarization states and phases can be selectively scattered out to the desired light beams.A manifestation of eight focusing beams with well-routed polarizations was experimentally *** design offers a new route to achieve the full control of optical polarizations and possibly advance the development in photonic information processing.

关键词： near-field interference phase modulation plasmonics polarization generator

Brain-derived neurotrophic factor and its related enzymes and receptors play important roles after hypoxic-ischemic brain damage

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Neural Regeneration Research 2021年第8期16卷 1453-1459页

作者： Liu-Lin Xiong Jie Chen Ruo-Lan Du Jia Liu Yan-Jun Chen Mohammed Al Hawwas Xin-Fu Zhou Ting-Hua Wang Si-Jin Yang Xue Bai National Traditional Chinese Medicine Clinical Research Base and Western Medicine Translational Medicine Research center Department of Cardiovascular DiseaseAffiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhouSichuan ProvinceChina Cinical and Health Sciences University of South AustraliaAdelaideAustralia Animal Zoology Department Institute of NeuroscienceKunming Medical UniversityKunmingYunnan ProvinceChina Institute of Neurological Disease Translational Neuroscience CenterWest China HospitalSichuan UniversityChengduSichuan ProvinceChina

Brain-derived neurotrophic factor(BDNF) regulates many neurological functions and plays a vital role during the recovery from central nervous system injuries. However, the changes in BDNF expression and associated factors following hypoxia-ischemia induced neonatal brain damage, and the significance of these changes are not fully understood. In the present study, a rat model of hypoxic-ischemic brain damage was established through the occlusion of the right common carotid artery, followed by 2 hours in a hypoxic-ischemic environment. Rats with hypoxic-ischemic brain damage presented deficits in both sensory and motor functions, and obvious pathological changes could be detected in brain tissues. The m RNA expression levels of BDNF and its processing enzymes and receptors(Furin, matrix metallopeptidase 9, tissuetype plasminogen activator, tyrosine Kinase receptor B, plasminogen activator inhibitor-1. and Sortilin) were upregulated in the ipsilateral hippocampus and cerebral cortex 6 hours after injury;however, the expression levels of these m RNAs were found to be downregulated in the contralateral hippocampus and cerebral cortex. These findings suggest that BDNF and its processing enzymes and receptors may play important roles in the pathogenesis and recovery from neonatal hypoxic-ischemic brain damage. This study was approved by the Animal Ethics Committee of the University of South Australia(approval No. U1.-1.) on July 30, 201..

关键词： brain injury brain-derived neurotrophic factor enzyme hypoxia-ischemia receptors recovery repair

Multi-level Aggregation of Conjugated Polymers in Solution:Advances and Challenges

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高分子科学:英文版 2023年第10期41卷 1498-1500页

作者： Jian Pei Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter of Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijingChina

Since the discovery of conductive polyacetylene,conjugated polymers have attracted considerable attention in the past decades for their applications in optoelectronic devices,such as organic field-effect transistors(OFETs),light-emitting diodes(OLEDs),and photovoltaics(OPVs).The intrinsic mechanical flexibility of conjugated polymers endows them as promising candidates for flexible and wearable *** iterative molecular design refinement and processing technique optimization,significant improvements in device performance have been *** mobility has reached over 1. cm^(2)·V^(−1.·s^(−1.,exceeding the benchmark of 1.cm^(2)·V^(−1.·s^(−1.set by their amorphous silicon *** conductivity of N-type polymer,poly(benzodifurandione)(PBFDO),exhibited a breakthrough over 2000 S·cm−1.making it an ideal conductor with excellent stability and *** power conversion efficiency(PCE)of conjugated polymer-based solar cells hits 1.%,comparable to the commercial polycrystalline silicon solar cells with 1.%−1.%***,conjugated polymers also show extinguished and promising performance in energy storage and biomedical applications.

关键词： optoelectronic breakthrough exceeding

Human exploitation of carnivores in Pleistocene China: A case study of the faunal remains from Shuidonggou Locality 7

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Science China Earth Sciences 2020年第1期63卷 132-144页

作者： Shuangquan ZHANG Yue ZHANG Shuwen PEI Xing GAO Key Laboratory for Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China

Hominin-animal interactions at Pleistocene archaeological sites have been the main subject of research during human evolution. However, in contrast to that of ungulates, little is known about the evidence of human processing of carnivore species in this time interval of China. In this paper, we present the first case report of an interactive relationship between carnivore species and hunter-gathers in Pleistocene China, based mainly on a detailed taphonomic study of the faunal remains from Shuidonggou Locality 7. It seems highly probable that hominins butchered some individuals of carnivores and roasted bone elements with adhering meat at the site;whereas it’s equally feasible that these animals were exploited by hominins mainly for their pelt or fur. In either way, evidence from the site indicates novel strategies in adaptive behaviors adopted by Late Pleistocene foragers in harsh environments of Northwest China.

关键词： Shuidonggou locality 7(SDG7) Upper Palaeolithic Cut marks Burned bones Taphonomy Northwest China