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General laws of funding for scientific citations:how citations change in funded and unfunded research between basic and applied sciences 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第4期71-89,共19页
Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relati... Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society. 展开更多
关键词 Research funding CITATIONS Scientific development Science diffusion Scientific laws Power law model Matthew effect Science policy Research policy Science of science Dynamics of science Evolution of science
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Research funding and citations in papers of Nobel Laureates in Physics, Chemistry and Medicine, 2019-2020 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第2期56-80,共25页
Purpose:The goal of this study is a comparative analysis of the relation between funding(a main driver for scientific research)and citations in papers of Nobel Laureates in physics,chemistry and medicine over 2019-202... Purpose:The goal of this study is a comparative analysis of the relation between funding(a main driver for scientific research)and citations in papers of Nobel Laureates in physics,chemistry and medicine over 2019-2020 and the same relation in these research fields as a whole.Design/methodology/approach:This study utilizes a power law model to explore the relationship between research funding and citations of related papers.The study here analyzes 3,539 recorded documents by Nobel Laureates in physics,chemistry and medicine and a broader dataset of 183,016 documents related to the fields of physics,medicine,and chemistry recorded in the Web of Science database.Findings:Results reveal that in chemistry and medicine,funded researches published in papers of Nobel Laureates have higher citations than unfunded studies published in articles;vice versa high citations of Nobel Laureates in physics are for unfunded studies published in papers.Instead,when overall data of publications and citations in physics,chemistry and medicine are analyzed,all papers based on funded researches show higher citations than unfunded ones.Originality/value:Results clarify the driving role of research funding for science diffusion that are systematized in general properties:a)articles concerning funded researches receive more citations than(un)funded studies published in papers of physics,chemistry and medicine sciences,generating a high Matthew effect(a higher growth of citations with the increase in the number of papers);b)research funding increases the citations of articles in fields oriented to applied research(e.g.,chemistry and medicine)more than fields oriented towards basic research(e.g.,physics).Practical implications:The results here explain some characteristics of scientific development and diffusion,highlighting the critical role of research funding in fostering citations and the expansion of scientific knowledge.This finding can support decision-making of policymakers and R&D managers to improve the effectiveness in allocating financial resources in science policies to generate a higher positive scientific and societal impact. 展开更多
关键词 Research funding CITATIONS Science diffusion Scientific change Science of Science Power-law distribution Basic research Applied research Matthew effect Nobel Laureates Nobel Prizes
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Patent Technology Research of AGV in China
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作者 Tan Xinjie Li Chenghao 《信息工程期刊(中英文版)》 2017年第1期34-41,共8页
关键词 技术开发 专利管理 AGV 中国 控制系统设计 数据可视化 技术改革 指导系统
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Research of Home Information Technology Adoption Model
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作者 Ao Shan Ren Weiyin +1 位作者 Lin Peishan Tang Shoulian 《信息通信技术》 2008年第5期10-16,共7页
The Information Technology at Home has caught the attention of various industries such as IT,Home Appliances,Communication,and Real Estate.Based on the information technology acceptance theories and family consumption... The Information Technology at Home has caught the attention of various industries such as IT,Home Appliances,Communication,and Real Estate.Based on the information technology acceptance theories and family consumption behaviors theories,this study summarized and analyzed four key belief variables i.e.Perceived Value,Perceived Risk,Perceived Cost and Perceived Ease of Use,which influence the acceptance of home information technology.The study also summaries three groups of external variables.They are social,industrial,and family influence factors.The social influence factors include Subjective Norm;the industry factors include the Unification of Home Information Technological Standards,the Perfection of Home Information Industry Value Chain,and the Competitiveness of Home Information Industry;and the family factors include Family Income,Family Life Cycle and Family Educational Level.The study discusses the relationship among these external variables and cognitive variables.The study provides Home Information Technology Acceptance Model based on the Technology Acceptance Model and the characteristics of home information technology consumption. 展开更多
关键词 家用信息技术 通信系统 发展现状 社会影响
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High-performance grinding of ceramic matrix composites
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作者 Jingfei Yin Jiuhua Xu Honghua Su 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第3期45-55,共11页
Ceramic matrix composites(CMCs)are highly promising materials for the next generation of aero-engines.However,machining of CMCs suffers from low efficiency and poor surfacefinish,which presents an obstacle to their wide... Ceramic matrix composites(CMCs)are highly promising materials for the next generation of aero-engines.However,machining of CMCs suffers from low efficiency and poor surfacefinish,which presents an obstacle to their wider application.To overcome these problems,this study investigates high-efficiency deep grinding of CMCs,focusing on the effects of grinding depth.The results show that both the sur-face roughness and the depth of subsurface damage(SSD)are insensitive to grinding depth.The material removal rate can be increased sixfold by increasing the grinding depth,while the surface roughness and SSD depth increase by only about 10%.Moreover,it is found that the behavior of material removal is strongly dependent on grinding depth.As the grinding depth is increased,fibers are removed in smaller sizes,with thefiber length in chips being reduced by about 34%.However,too large a grinding depth will result in blockage by chip powder,which leads to a dramatic increase in the ratio of tangential to normal grinding forces.This study demonstrates that increasing the depth of cut is an effective approach to improve the machining efficiency of CMCs,while maintaining a good surfacefin-ish.It provides the basis for the further development of high-performance grinding methods for CMCs,which should facilitate their wider application. 展开更多
关键词 Ceramic matrix composite GRINDING Surfacefinish Subsurface damage Fiber breakage
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Research Progress of Biomass-Based Porous Oil-Absorbing Materials
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作者 Yifan Sun Yuanyuan Zhang +5 位作者 Ziyi Tian Hailang Liu Siying Chen Xujuan Huang Zhaosheng Cai Bo Fang 《Journal of Renewable Materials》 EI CAS 2024年第11期1837-1856,共20页
As oil is now an important resource for the survival and development of mankind,the consumption of oil continues to increase each year,and there have been a number of major oil spills in history,such as the oil spill ... As oil is now an important resource for the survival and development of mankind,the consumption of oil continues to increase each year,and there have been a number of major oil spills in history,such as the oil spill from the Deepwater Horizon drilling rig.Therefore,oil spills during storage and transportation have become an issue of serious concern.Current methods such as incineration and chemical methods cause secondary environmental pollution and fail to enable resource recovery.The adsorption method by porous materials has attracted worldwide attention due to its simplicity,portability,and efficiency.It has become an important factor to explore how porous adsorption materials can adsorb efficiently and reduce environmental pollution.Biomass resources are abundant,cost-effective,biodegradable,and sustainable,which have been extensively explored for the production of porous materials.Herein,recent advances in cellulose-based,chitosan-based,wood-based and other biomassbased oil-absorbing porous materials are summarized,and cellulose-based porous materials,such as nanocellulose,bacterial cellulose,and regenerated cellulose and their related derivatives,are further expanded.In addition,typical environmentally friendly manufacturing methods and the oil adsorption capacities of various oil-absorbing porous materials are also discussed.Compared with the traditional petrochemical adsorption materials,the development advantages of biomass porous oil absorption materials are analyzed.The reasons hindering the popularization and use of oil-absorbing biomass materials are summarized and the future application fields are prospected. 展开更多
关键词 BIOMASS CELLULOSE CHITOSAN WOOD oil-absorbing materials
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Evaluation of large language models for the classification of medical device software
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作者 Yu Han Aaron Ceross +2 位作者 Florence Bourgeois Paulo Savaget Jeroen H.M.Bergmann 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期819-822,共4页
Amidst the rapidly expanding integration of large language models(LLMs)across various sectors(ranging from everyday applications to specialized fields demanding stringent regulatory adherence),our investigation seeks ... Amidst the rapidly expanding integration of large language models(LLMs)across various sectors(ranging from everyday applications to specialized fields demanding stringent regulatory adherence),our investigation seeks to determine how well these models can support medical device software classification.Medical device classification functions to systematically categorize devices according to their designated use,associated risk levels,and requisite regulatory oversight,thereby providing a structured framework for ensuring safety and efficacy as mandated by regulatory authorities. 展开更多
关键词 EVERYDAY demanding thereby
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Overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with Obstacles Using Lattice Boltzmann Method
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作者 Siham Hammid Khatir Naima +7 位作者 Omolayo M.Ikumapayi Cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer Ali Hussien Younes Menni 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期273-299,共27页
The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstac... The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower walls.The research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding environment.Temperature jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle boundaries.The study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and 0.05.The outcomes indicate that rarefaction has a significant impact on the velocity and temperature distribution.The presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the outlet.In MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the MC.The findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications. 展开更多
关键词 MICROFLUID rarefied flow LBM MICROCHANNEL Knudsen number numerical simulation
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Implications of de Facto Reuse on Future Regulatory Developments for Beaufort-Jasper Water & Sewer Authority in Okatie, South Carolina, USA
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作者 Tricia H. Kilgore Shubhashini Oza +1 位作者 Jeremy Hatfield Katherine Y. Bell 《Journal of Environmental Protection》 2024年第2期173-192,共20页
A significant portion of the national water supply can be attributed to de facto or unplanned potable reuse, though the extent of its contribution is difficult to estimate. Fortunately, the contribution of Water Resou... A significant portion of the national water supply can be attributed to de facto or unplanned potable reuse, though the extent of its contribution is difficult to estimate. Fortunately, the contribution of Water Resource Recovery Facility (WRRF) effluent to waters that supply drinking water treatment plants has been documented by some communities. In the United States (US), among the top 25 most impacted drinking water treatment plants by upstream WRRF, 16% of the influent flow to the drinking water treatment plant under average streamflow and up to 100% under low-flow conditions is WRRF effluent. Currently, the full extent of de facto reuse in the US may be much higher because of population growth. The scenario is no different for Beaufort-Jasper Water and Sewer Authority (BJWSA) in South Carolina, US, with contributions to the Savannah River originating from numerous WRRF and other upstream dischargers. South Carolina coastal utilities such as BJSWA are considering direct and indirect potable reuse options, driven by disposal limitations and challenges. Currently, South Carolina does not have a framework, guidelines, or regulations for reuse, but discussions have started among the regulated community. In addition to understanding the extent of de facto reuse, the state will need to develop standards and best practices to enable future adoption of planned potable reuse solutions to water resources challenges. Such guidance should address human health risk management and technical considerations regarding treatment in addition to other factors, including source control, storage, fail-safe operation, monitoring, non-cost factors, and public acceptance. This study conducted a mapping assessment specific to BJWSA, sampled at four locations on Savannah River, and observed that de facto reuse is approximately 4.6% to 5.9% during low-flow months and is within the range generally observed nationwide. When coupled with evidence that planned potable reuse can improve human health and environmental risks, this practice is a meaningful option in the water supply portfolio for many utilities. 展开更多
关键词 Water Reuse De Facto Reuse Planned Potable Reuse Water Recycling Wastewater Derived Contaminants
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Analysis of Gestational Diabetes Mellitus (GDM) and Its Impact on Maternal and Fetal Health: A Comprehensive Dataset Study Using Data Analytic Tool Power BI
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作者 Shahistha Jabeen Hashim Arthur McAdams 《Journal of Data Analysis and Information Processing》 2024年第2期232-247,共16页
Gestational Diabetes Mellitus (GDM) is a significant health concern affecting pregnant women worldwide. It is characterized by elevated blood sugar levels during pregnancy and poses risks to both maternal and fetal he... Gestational Diabetes Mellitus (GDM) is a significant health concern affecting pregnant women worldwide. It is characterized by elevated blood sugar levels during pregnancy and poses risks to both maternal and fetal health. Maternal complications of GDM include an increased risk of developing type 2 diabetes later in life, as well as hypertension and preeclampsia during pregnancy. Fetal complications may include macrosomia (large birth weight), birth injuries, and an increased risk of developing metabolic disorders later in life. Understanding the demographics, risk factors, and biomarkers associated with GDM is crucial for effective management and prevention strategies. This research aims to address these aspects comprehensively through the analysis of a dataset comprising 600 pregnant women. By exploring the demographics of the dataset and employing data modeling techniques, the study seeks to identify key risk factors associated with GDM. Moreover, by analyzing various biomarkers, the research aims to gain insights into the physiological mechanisms underlying GDM and its implications for maternal and fetal health. The significance of this research lies in its potential to inform clinical practice and public health policies related to GDM. By identifying demographic patterns and risk factors, healthcare providers can better tailor screening and intervention strategies for pregnant women at risk of GDM. Additionally, insights into biomarkers associated with GDM may contribute to the development of novel diagnostic tools and therapeutic approaches. Ultimately, by enhancing our understanding of GDM, this research aims to improve maternal and fetal outcomes and reduce the burden of this condition on healthcare systems and society. However, it’s important to acknowledge the limitations of the dataset used in this study. Further research utilizing larger and more diverse datasets, perhaps employing advanced data analysis techniques such as Power BI, is warranted to corroborate and expand upon the findings of this research. This underscores the ongoing need for continued investigation into GDM to refine our understanding and improve clinical management strategies. 展开更多
关键词 Gestational Diabetes Visualization Data Analytics Data Modelling PREGNANCY Power BI
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Experimental Research on the Fabrication of Modular Devices for Drilling Using PLA for Model Parts
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作者 Diana Băilă Remigiusz Łabudzki +1 位作者 Igor Fodchuk Mirian Bonilla 《Open Journal of Applied Sciences》 2024年第10期2790-2800,共11页
The objective of the work is to determine the influence of the PLA melting temperature during 3D printing on the dimensional accuracy of the model parts. Two modular drilling devices were also made using PLA model par... The objective of the work is to determine the influence of the PLA melting temperature during 3D printing on the dimensional accuracy of the model parts. Two modular drilling devices were also made using PLA model parts. The model parts were 3D printed using FDM technology and the ZMorph 2.0 hybrid 3D printer. The accuracy of 3D printing of the model part influences the realization of modular devices. In recent years, technology has evolved a lot, and the need to have the most efficient manufacturing equipment has increased. This is the reason for the development of 3D printers using FDM technology for plastic parts. The software used by these 3D printers used in FDM technology is very sophisticated, as they allow the manufacture of very precise 3D prototypes, identical to the designed 3D model, through modern additive manufacturing techniques. The quality and mechanical strength of the prototypes obtained using 3D printers is very good. The materials used by the 3D printers manufactured by FDM are cheap and accessible. These 3D printers are used to make three-dimensional objects (gears, flanges, bearings, covers, casings, mechanisms, figurines, interior and exterior design elements, architectural models, medical models). 展开更多
关键词 Modular Device 3D Printer FDM-Fused Deposition Modeling Dimensional Accuracy Melting Temperature
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Dynamics Analysis of the Baiyun Sag in the Pearl River Mouth Basin,North of the South China Sea 被引量:14
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作者 SUN Zhen ZHONG Zhihong +5 位作者 ZHOU Di PANG Xiong HUANG Chunju CHEN Changmin HE Min XU Hehua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期73-83,共11页
The Baiyun sag is a deep one developing on the slope of the Pearl River Mouth Basin. It occurs as a composite graben horizontally, and is composed of two sub-sags versus one low uplift. Vertically, the sedimentary arc... The Baiyun sag is a deep one developing on the slope of the Pearl River Mouth Basin. It occurs as a composite graben horizontally, and is composed of two sub-sags versus one low uplift. Vertically, the sedimentary architecture could be divided into three layers, i.e. the faulted layer on the bottom, the faulted-ductile stretching layer in the middle and the draping layer on the top. The main rifting stage of the sag is supposed to be characterized by ductile extension and thinning of the crust. The special deformation pattern is probably attributed to the fact that the Baiyun sag is located in the transfer zone of the pre-existing weak zone, which made the sag a strongly deformed area, characterized by the greatly thinned lithosphere and active magmatism. The highly rising mantle under the Baiyun sag should be an important mechanism responsible for the ductile deformation, which caused partial melting of the upper mantle. Upweiling to the upper crust and the sedimentary layers, the partial melting materials accommodated extensional strain and caused non-faulted vertical subsidence. Magma was collected under the transfer zone after the first stage of rifting, and transferred laterally in a direction perpendicular to the extension to the ENE and WSW parts of the sag and upwelled along the NW-trending basal faults, where WNW-trending shear faults developed in swarms. The faulting activity and sedimentation history of the Baiyun sag may have been affected by the ocean ridge jump around 24 Ma and the cessation of sea floor spreading around 16 Ma. 展开更多
关键词 Baiyun sag dynamics analysis transfer zone ductile extension
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Enhanced Photocatalytic Activity of ZnO/CuO Nanocomposites Synthesized by Hydrothermal Method 被引量:5
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作者 Tongqin Chang Zijiong Li +2 位作者 Gaoqian Yun Yong Jia Hongjun Yang 《Nano-Micro Letters》 SCIE EI CAS 2013年第3期163-168,共6页
In this paper, we have demonstrated a facile and low-cost synthesis of the ZnO/CuO nanocomposites by two-step hydrothermal methods. The photocatalytic properties of the as-synthesized ZnO/CuO nanocomposites have been ... In this paper, we have demonstrated a facile and low-cost synthesis of the ZnO/CuO nanocomposites by two-step hydrothermal methods. The photocatalytic properties of the as-synthesized ZnO/CuO nanocomposites have been evaluated by the photodegradation of methylene blue(MB) and methyleneorange(MO) under UV irradiation. Experimental results show that MB and MO can be degraded completely within 15 and 25 min by the ZnO/CuO nanocomposites and its photodegradation rate is 6 times faster than that of pure ZnO. This enhanced photocatalytic activity can be ascribed to the low recombination probability of photo-induced carriers due to the efficient charge transfer in the nanocomposites. The as-synthesized ZnO/CuO nanocomposite may be a promising candidate for dye photodegradation of wastewaters. 展开更多
关键词 Photocatalytic degradation NANOCOMPOSITES ZnO/CuO HYDROTHERMAL
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Modeling of numerical simulation and experimental verification for carburizing-nitriding quenching process 被引量:9
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作者 R. MUKAI T. MATSUMOTO +3 位作者 JU Dong-ying T. SUZUKI H. SAITO Y. ITO 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期566-571,共6页
A model considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is presented to examine metallo-thermo-mechanical behavior during carburized and nitrided quenchi... A model considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is presented to examine metallo-thermo-mechanical behavior during carburized and nitrided quenching. Coupled simulation of diffusion, phase transformation and stress/strain provides the final distribution of carbon and nitrogen contents as well as residual stress and distortion. Effects of both transformation and lattice expansion induced by carbon and nitrogen absorption were introduced into calculating the evolution of the internal stress and strain. In order to verify the method and the results, the simulated distributions of carbon and nitrogen content and residual stress/strain of a ring model during carburized and nitrided quenching were compared with the measured data. 展开更多
关键词 金属热处理 渗碳 渗氮 淬火过程 数值模拟 模型 实验验证
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Influence of laser linewidth on performance of Brillouin optical time domain reflectometry 被引量:5
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作者 郝蕴琦 叶青 +2 位作者 潘政清 蔡海文 瞿荣辉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期257-261,共5页
The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewi... The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewidth of spontaneous Brillouin scattering remains almost constant when the laser linewidth is less than 1 MHz at the same pulse width; otherwise, it increases sharply. A comparison between a fiber laser (FL) with 4-kHz linewidth at 3 dB and a distributed feedback (DFB) laser with 3-MHz linewidth is made experimentally. When a constant laser power is launched into the sensing fiber, the fitting linewidths of the beat signals (backscattered Brillouin light and local oscillator (LO)) is about 5 MHz wider for the DFB laser than for the FL and the intensity of the beat signal is about a half. Furthermore, the frequency fluctuation in the long sensing fiber is lower for the FL source, yielding about 2 MHz less than that of the DFB laser, indicating higher temperature/strain resolution. The experimental results are in good agreement with the numerical simulations. 展开更多
关键词 Brillouin optical time domain reflectometry (BOTDR) laser linewidth distributed feedback laser fiber laser
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Novel application of multispectral refraction topography in the observation of myopic control effect by orthokeratology lens in adolescents 被引量:8
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作者 Ning-Jun Ni Fei-Yan Ma +5 位作者 Xiao-Mei Wu Xiao Liu Hong-Yan Zhang Yi-Fei Yu Mei-Chen Guo Sheng-Yong Zhu 《World Journal of Clinical Cases》 SCIE 2021年第30期8985-8998,共14页
BACKGROUND Myopia,as one of the common ocular diseases,often occurs in adolescence.In addition to the harm from itself,it may also lead to serious complications.Thus,prevention and control of myopia are attracting mor... BACKGROUND Myopia,as one of the common ocular diseases,often occurs in adolescence.In addition to the harm from itself,it may also lead to serious complications.Thus,prevention and control of myopia are attracting more and more attention.Previous research revealed that single-focal glasses and orthokeratology lenses(OK lenses)played an important part in slowing down myopia and preventing high myopia.AIM To compare the clinical effects of OK lenses and frame glasses against the increase of diopter in adolescent myopia and further explore the mechanism of the OK lens.METHODS Changes in diopter and axial length were collected among 70 adolescent myopia patients(124 eyes)wearing OK lenses for 1 year(group A)and 59 adolescent myopia patients(113 eyes)wearing frame glasses(group B).Refractive states of their retina were inspected through multispectral refraction topography.The obtained hyperopic defocus was analyzed for the mechanism of OK lenses on slowing down the increase of myopic diopter by delaying the increase of ocular axis length and reducing the near hyperopia defocus.RESULTS Teenagers in groups A and B were divided into low myopia(0 D--3.00 D)and moderate myopia(-3.25 D--6.00 D),without statistical differences among gender and age.After 1-year treatment,the increase of diopter and axis length and changes of retinal hyperopic defocus amount of group A were significantly less than those of group B.According to the multiple linear analysis,the retinal defocus in the upper,lower,nasal,and temporal directions had almost the same effect on the total defocus.The amount of peripheral retinal defocus(15°-53°)in group A was significantly lower than that in group B.CONCLUSION Multispectral refraction topography is progressive and instructive in clinical prevention and control of myopia. 展开更多
关键词 Multispectral refraction topography Myopia Retinal hyperopic defocus Eye axis DIOPTER Orthokeratology lens Frame glasses
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VARIABILITY IN THE WESTERN PACIFIC SUBTROPICAL HIGH AND ITS RELATIONSHIP WITH SEA TEMPERATURE VARIATION CONSIDERING THE BACKGROUND OF CLIMATE WARMING OVER THE PAST 60 YEARS 被引量:4
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作者 SUN Sheng-jie LI Dong-liang 《Journal of Tropical Meteorology》 SCIE 2018年第4期468-480,共13页
By adopting characteristic index data for the Western Pacific Subtropical High(WPSH) from the National Climate Center of China, U.S. National Centers for Environmental Prediction-National Center for Atmospheric Resear... By adopting characteristic index data for the Western Pacific Subtropical High(WPSH) from the National Climate Center of China, U.S. National Centers for Environmental Prediction-National Center for Atmospheric Research(NCEP/NCAR) reanalysis data, and the National Oceanic and Atmospheric Administration(NOAA) sea surface temperature(SST) data, we studied the WPSH variability considering the background of climate warming by using a Gaussian filter, moving averages, correlation analysis, and synthetic analysis. Our results show that with climate warming over the past 60 years, significant changes in the WPSH include its enlarged area, strengthened intensity,westward extended ridge point and southward expanded southern boundary, as well as enhanced interannual fluctuations in all these indices. The western ridge point of the WPSH consistently varies with temperature changes in the Northern Hemisphere, but the location of the ridgeline varies independently. The intensity and area of the WPSH were both significantly increased in the late 1980 s. Specifically, the western ridge point started to significantly extend westward in the early 1990 s, and the associated interannual variability had a significant increase in the late 1990 s; in addition, the ridgeline was swaying along the north-south-north direction, and the corresponding variability was also greatly enhanced in the late 1990 s. With climate warming, the SST increase becomes more weakly correlated with the WPSH intensity enhancement but more strongly correlated with the westward extension of the ridge point in the equatorial central and eastern Pacific Ocean in winter, corresponding to an expanding WPSH in space. In the northern Pacific in winter, the SST decrease has a weaker correlation with the southerly location of the ridgeline but also a stronger correlation with the westward extension of the ridge point. In the tropical western Pacific in winter, the correlations of the SST decrease with the WPSH intensity enhancement, and the westward extension of the ridge point is strengthened. These observations can be explained by strengthened Hadley circulations, the dominant effects of the southward shift, and additional effects of the weakened ascending branch of the Walker circulation during warm climatological periods,which consequently lead to strengthened intensities, increased areas, and southward expansions of the WPSH in summer. 展开更多
关键词 climatological TEMPERATURE FLUCTUATION Western PACIFIC SUBTROPICAL High (WPSH) characteristic variations sea surface TEMPERATURE (SST) vertical circulation
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Effect of mixing process on the luminescent properties of SrAl_2O_4:Eu^(2+),Dy^(3+) long afterglow phosphors 被引量:2
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作者 吕霄 孙猛 +1 位作者 张俊英 王天民 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第1期150-152,共3页
A new mixing method was developed for solid-state reaction synthesis of SrAl2O4:Eu2+,Dy3+ long afterglow phosphors.The morphology and crystal structure of the phosphors were analyzed with scanning electron microscope(... A new mixing method was developed for solid-state reaction synthesis of SrAl2O4:Eu2+,Dy3+ long afterglow phosphors.The morphology and crystal structure of the phosphors were analyzed with scanning electron microscope(SEM) and X-ray diffractometer(XRD).The excitation and emission spectra of the long afterglow phosphors were measured,and the main emission band was around 514 nm.The decay time of the product was measured and compared with the phosphors prepared using dry-mixing method and wet-mixing method.It ... 展开更多
关键词 long afterglow PHOSPHOR SRAL2O4 trap level DECAY rare earths
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Development in p-type Doping of ZnO 被引量:2
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作者 俞丽萍 朱其锵 +1 位作者 FAN Dayong IANZili 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1184-1187,共4页
Zinc oxide (ZnO) is a wide band-gap material of the Ⅱ-Ⅵ group with excellent optical properties for optoelectronics applications, such as the flat panel displays and solar cells used in sports tournament. Despite ... Zinc oxide (ZnO) is a wide band-gap material of the Ⅱ-Ⅵ group with excellent optical properties for optoelectronics applications, such as the flat panel displays and solar cells used in sports tournament. Despite its advantages, the application of ZnO is hampered by the lack of stable p-type doping. In this paper, the recent progress in this field was briefly reviewed, and a comprehensive summary of the research was carded out on ZnO fabrication methods and its electrical, optical, and magnetic properties were presented. 展开更多
关键词 ZNO p-type doping fabrication method optoelectronics applicatio
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Effect of inertia nonlinearity on dynamic response of an asymmetric building equipped with tuned mass dampers 被引量:2
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作者 Hassan Rezazadeh Fereidoun Amini Majid Amin Afshar 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第2期499-513,共15页
This study investigates the effect of nonlinear inertia on the dynamic response of an asymmetric building equipped with Tuned Mass Dampers(TMDs).In the field of structural engineering,many researchers have developed m... This study investigates the effect of nonlinear inertia on the dynamic response of an asymmetric building equipped with Tuned Mass Dampers(TMDs).In the field of structural engineering,many researchers have developed models to study the behavior of nonlinear TMDs,but the effect of nonlinear inertia has not received as much attention for asymmetric buildings.To consider nonlinear inertia,the equations of motion are derived in a local rotary coordinates system.The displacements and rotations of the modeled building and TMDs are defined by five-degree-of-freedom(5-DOFs).The equations of motion are derived by using the Lagrangian method.Also in the proposed nonlinear model,the equations of motion are different from a conventional linear model.In order to compare the response of the proposed nonlinear model and a conventional linear model,numerical examples are presented and the response of the modeled buildings are derived under harmonic and earthquake excitations.It is shown that if the nonlinear inertia is considered,the response of the modeled structures changes and the conventional linear approach cannot adequately model the dynamic behavior of the asymmetric buildings which are equipped with TMDs. 展开更多
关键词 Nonlinear INERTIA tuned mass DAMPER ASYMMETRIC buildings harmonic EXCITATION SEISMIC EXCITATION
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