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The Correlation of Hospital Operational Efficiency and Average Length of Stay in China: A Study Based on Provincial Level Data 被引量:1
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作者 Qian Liu Xinyu Zhang +4 位作者 Yanan Guo Yao Zhang Yaxuan Wang Bo Li Yaogang Wang 《Journal of Biosciences and Medicines》 2016年第12期49-55,共7页
Objective: To measure the hospital operation efficiency, study the correlation between average length of stay and hospital operation efficiency, analyze the importance of shortening average length of stay to the impro... Objective: To measure the hospital operation efficiency, study the correlation between average length of stay and hospital operation efficiency, analyze the importance of shortening average length of stay to the improvement of the hospital operation efficiency and put forward relevant policy suggestion. Methods: Based on China provincial panel data from 2003 to 2012, the hospital operation efficiencies are calculated using Super Efficiency Data Envelopment Analysis model, and the correlation between average length of stay and hospital operation efficiency is tested using Spearman rank correlation coefficient test. Results: From 2003 to 2012, the average of national hospital operation efficiency was increasing slowly and the hospital operations were inefficient in most of the areas. The national hospital operation efficiency is negatively correlated to the average length of stay. Conclusion: Measures should be taken to set average length of stay in a scientific and reasonable way, improve social and economic benefits based on the improvement of efficiency. 展开更多
关键词 average Length of Stay Hospital Operation efficiency CORRELATION Super efficiency Data Envelopment Analysis
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Investigation of thermal behavior of energetic and non-energetic binders on luminous efficiency of high performance miniature flares
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作者 Saeid Bagherpour Mohammad Mahdavi Ebrahim Abedini 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第2期193-197,共5页
Miniature flares containing magnesium/sodium nitrate compounded with different binders were studied for increasing luminosity and luminous efficiency in various fuel oxidizer ratio and flare diameters.Unsaturated poly... Miniature flares containing magnesium/sodium nitrate compounded with different binders were studied for increasing luminosity and luminous efficiency in various fuel oxidizer ratio and flare diameters.Unsaturated polyester, Bisphenol-A epoxy resin, calcium resinate, and nitrocellulose were used as binders for construction the flares. Experimental results showed that luminous efficiency was higher for polyester based flares. Due to the difference in decomposition progress of various binders and the exothermic reaction between binder and oxidizer the luminous efficiency of the mixtures were 31000,28900, 27800 and 25100 cd respectively for polyester, epoxy, calcium resinate, and nitrocellulose. It was found that nitrocellulose as an energetic binder produces the highest light intensity in comparison to other binders, but the burning rate is higher and the burning time is lower than the other binders.Thermal analysis of four binders showed that the heat of reactions was directly related to the amount of light output and luminosity. 展开更多
关键词 MINIATURE FLARE ILluminATING compositions luminous efficiency Binder
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AVERAGE BRIGHTNESS TEMPERATURE OF ANTENNA APERTURE
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作者 Li Zongqian(Dept. of Electronics Engineering, Tsinghua University, Beijing 100084) 《Journal of Electronics(China)》 1997年第2期191-193,共3页
This paper presented an idea for the average brightness temperature of lossless antenna aperture, gave its expression for matched and dismatched noise source. This expression showed that the average brightness tempera... This paper presented an idea for the average brightness temperature of lossless antenna aperture, gave its expression for matched and dismatched noise source. This expression showed that the average brightness temperature of antenna aperture related with three factors: the noise temperature of noise source, the reflection coefficient of noise source, and the aperture efficiency. 展开更多
关键词 ANTENNA APERTURE average BRIGHTNESS temperature Noise source REFLECTION COefficiENT APERTURE efficiency
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Calculation and Improvement on External Quantum Efficiency of OLEDs
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作者 LI Chuan-nan XIE Wen-fa LIU Shi-yong 《Semiconductor Photonics and Technology》 CAS 2006年第1期1-4,共4页
The calculation of the external quantum efficiency(η_ ext ) of organic light-emitting devices(OLEDs) is presented theoretically. The basic idea is to obtain η_ ext by calculating the fraction of the generated light ... The calculation of the external quantum efficiency(η_ ext ) of organic light-emitting devices(OLEDs) is presented theoretically. The basic idea is to obtain η_ ext by calculating the fraction of the generated light that can escape through the top surface and the average transmittance over the escape cone. During the calculation, the effects of the interference, absorption and multiple reflections are neglected. Then a result of a typical 8-tris-hydroxyquinoline aluminum(Alq_ 3 )-based OLEDs on a planar glass substrate is obtained. And a twice increase in η_ ext can be achieved by using a high-index-glass substrate with an antireflection coating(SiO_ 2 ) on substrate surface. 展开更多
关键词 External quantum efficiency OLEDS average transmittance Antireflection coating
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On the Maximum of Wind Power Efficiency
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作者 Gerhard Kramm Gary Sellhorst +3 位作者 Hannah K. Ross John Cooney Ralph Dlugi Nicole Mölders 《Journal of Power and Energy Engineering》 2016年第1期1-39,共39页
In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in ... In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in the atmospheric boundary layer (ABL) because the ABL is mainly governed by turbulent motions. We also demonstrate that the stream tube model customarily applied to derive the Rankine-Froude theorem must be corrected in the sense of Glauert to provide an appropriate value for the axial velocity at the rotor area. Including this correction leads to the Betz-Joukowsky limit, the maximum efficiency of 59.3 percent. Thus, Gorban’ et al.’s 30% value may be valid in water, but it has to be discarded for the atmosphere. We also show that Joukowsky’s constant circulation model leads to values of the maximum efficiency which are higher than the Betz-Jow-kowsky limit if the tip speed ratio is very low. Some of these values, however, have to be rejected for physical reasons. Based on Glauert’s optimum actuator disk, and the results of the blade-element analysis by Okulov and S&oslashrensen we also illustrate that the maximum efficiency of propeller-type wind turbines depends on tip-speed ratio and the number of blades. 展开更多
关键词 Wind Power Power efficiency General Momentum Theory Axial Momentum Theory Blade Element Analysis Betz-Joukowsky Limit Joukowsky’s Constant Circulation Model Glauert’s Optimum Actuator Disk Balance Equation for Momentum Equation of Continuity Balance Equation for Kinetic Energy Reynolds’ average Hesselberg’s average Favre’s average Bernoulli’s Equation Integral Equations
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YAGG:Ce transparent ceramics with high luminous efficiency for solid-state lighting application 被引量:20
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作者 Hui HUA Shaowei FENG +7 位作者 Zhongyu OUYANG Hezhu SHAO Haiming QIN Hui DING Qiping DU Zhijun ZHANG Jun JIANG Haochuan JIANG 《Journal of Advanced Ceramics》 SCIE CSCD 2019年第3期389-398,共10页
A series of Y2.985Al5–xGaxO12:0.015Ce(YAGG:Ce,x=0,1,2,3,4,5)transparent ceramics were prepared via a solid-state reaction method.Two-step sintering technique was proved to be an effective approach to prepare function... A series of Y2.985Al5–xGaxO12:0.015Ce(YAGG:Ce,x=0,1,2,3,4,5)transparent ceramics were prepared via a solid-state reaction method.Two-step sintering technique was proved to be an effective approach to prepare functional ceramics with high Ga concentration,and Y3Ga5O12(YGG)transparent ceramic was successfully prepared for the first time.According to the variation of Al/Ga ratio,regulation of band structure and luminescence properties of YAGG:Ce transparent ceramics were effectively investigated.When Ga substitutes Al sites,the tetrahedral site is more favorable compared to the octahedral site for Ga to occupy according to the first-principle calculation.A continuous blue shift of the emission from 565 to 515 nm was achieved as Ga was gradually introduced into Y3Al5O12:Ce matrix.High quality green light was obtained by coupling the YAGG:Ce ceramics with commercial blue InGaN chips.Transparent luminescence ceramics accomplished in this work can be quite prospective for high power LED application. 展开更多
关键词 YAGG:Ce transparent ceramics TWO-STEP sintering Al/Ga ratio luminous efficiency green-emitting LEDS
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Semitransparent polymer solar cells with 12.37% efficiency and 18.6% average visible transmittance 被引量:4
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作者 Zhenghao Hu Zhi Wang +1 位作者 Qiaoshi An Fujun Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2020年第2期131-137,88,共8页
A series of opaque and semitransparent polymer solar cells(PSCs)were fabricated with PM6:Y6 as active layers,and 100 nm Al or 1 nm Au/(20,15,10 nm)Ag layer as electrode,respectively.The power conversion efficiency(PCE... A series of opaque and semitransparent polymer solar cells(PSCs)were fabricated with PM6:Y6 as active layers,and 100 nm Al or 1 nm Au/(20,15,10 nm)Ag layer as electrode,respectively.The power conversion efficiency(PCE)of opaque PSCs arrives to 15.83%based on the optimized active layer with a thickness of 100 nm,resulting from the well-balanced photon harvesting and charge collection.Meanwhile,the 100 nm PM6:Y6 blend film exhibits a 50.5%average visible transmittance(AVT),which has great potential in preparing efficient semitransparent PSCs.The semitransparent electrodes were fabricated with 1 nm Au and different thick Ag layers,exhibiting a relatively high transmittance in visible light range and relatively low transmittance in near infrared range.The PCE and AVT of the semitransparent PSCs can be adjusted from 14.20%to 12.37%and from 8.9%to 18.6%along with Ag layer thickness decreasing from 20 to 10 nm,respectively,which are impressive values among the reported semitransparent PSCs. 展开更多
关键词 SEMITRANSPARENT polymer solar cells Narrow band gap materials SEMITRANSPARENT electrode Power conversion efficiency average VISIBLE TRANSMITTANCE PHOTOPIC response of human eye
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Reform of China’s IPO Mechanism: Enhancing Efficiency and Optimizing the Market Ecosystem
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作者 Yu Yuxin Xu Lin 《Contemporary Social Sciences》 2024年第6期40-64,共25页
A well-developed financial market system is crucial for supporting high-quality development in the new era.Initial Public Offerings(IPOs)are essential for enabling financial markets to facilitate new industrialization... A well-developed financial market system is crucial for supporting high-quality development in the new era.Initial Public Offerings(IPOs)are essential for enabling financial markets to facilitate new industrialization while accelerating the development of a manufacturing powerhouse.Therefore,research on IPO mechanism reform holds significant practical implications.This paper examines the impact of China’s IPO mechanism reform by studying the equilibrium relationship between the primary market and the lending market.Using empirical analysis,we compare the average return on online subscriptions for newly listed shares using the risk-free rate before and after China’s 2015 IPO mechanism reform,as well as analyze the underlying mechanisms driving excess returns during both periods.Our findings indicate a gradual alignment of returns in the primary and lending markets,with institutional arbitrage opportunities between them diminishing.The reforms have effectively enhanced market mechanisms,improved pricing capabilities,rationalized participant behavior,and optimized the securities market ecosystem.These improvements have contributed to the market’s equilibrium and enhanced the market’s ability to interpret information.However,further improvements to the IPO mechanism are necessary,including deeper market-oriented reforms,standardization of participant behavior,acceleration of a comprehensive registration system,and stronger information disclosure and quality management. 展开更多
关键词 IPO mechanism average return on online subscriptions excess returns market efficiency
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基于改进YOLOv8的煤矿输送带异物检测 被引量:1
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作者 洪炎 汪磊 +2 位作者 苏静明 汪瀚涛 李木石 《工矿自动化》 CSCD 北大核心 2024年第6期61-69,共9页
现有基于深度学习的输送带异物检测模型较大,难以在边缘设备部署,且对不同尺寸异物和小目标异物存在错检、漏检情况。针对上述问题,提出一种基于改进YOLOv8的煤矿输送带异物检测方法。采用深度可分离卷积、压缩和激励(SE)网络将YOLOv8... 现有基于深度学习的输送带异物检测模型较大,难以在边缘设备部署,且对不同尺寸异物和小目标异物存在错检、漏检情况。针对上述问题,提出一种基于改进YOLOv8的煤矿输送带异物检测方法。采用深度可分离卷积、压缩和激励(SE)网络将YOLOv8主干网络中C2f模块的Bottleneck重新构建为DSBlock,在保持模型轻量化的同时提升检测性能;为增强对不同尺寸目标物体信息的获取能力,引入高效通道注意力(ECA)机制,并对ECA的输入层进行自适应平均池化和自适应最大池化操作,得到跨通道交互MECA模块,以增强模块的全局视觉信息,进一步提升异物识别精度;将YOLOv8的3个检测头修改为4个轻量化小目标检测头,以增强对小目标的敏感性,有效降低小目标异物的漏检率和错检率。实验结果表明:改进YOLOv8的精确度达91.69%,mAP@50达92.27%,较YOLOv8分别提升了3.09%和4.07%;改进YOLOv8的检测速度达73.92帧/s,可充分满足煤矿输送带异物实时检测的需求;改进YOLOv8的精确度、mAP@50、参数量、权重大小和每秒浮点运算数均优于SSD,Faster-RCNN,YOLOv5,YOLOv7-tiny等主流目标检测算法。 展开更多
关键词 输送带异物检测 YOLOv8 SE网络 高效通道注意力机制 轻量化 小目标检测 自适应平均池化 自适应最大池化
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连续时间完全-限定(K=2)两级轮询系统性能分析
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作者 杨志军 黄文洁 丁洪伟 《计算机工程》 CSCD 北大核心 2024年第1期191-197,共7页
为了实现区分网络优先级、保证公平性、提高普通站点的性能和效率,在完全-限定(K=1)两级轮询控制系统模型的基础上,提出连续时间完全-限定(K=2)两级轮询控制系统模型。在该模型中,使用限定(K=2)服务和完全服务分别对普通站点和中心站点... 为了实现区分网络优先级、保证公平性、提高普通站点的性能和效率,在完全-限定(K=1)两级轮询控制系统模型的基础上,提出连续时间完全-限定(K=2)两级轮询控制系统模型。在该模型中,使用限定(K=2)服务和完全服务分别对普通站点和中心站点进行服务。中心站点转换到普通站点进行服务时,使用捎带查询方式。在此基础上,采用马尔可夫链和概率母函数的数学方法建立该轮询系统模型,并推导平均排队队长和时延。利用MATLAB进行仿真实验,结果表明:理论值与仿真值误差较小,验证了理论分析的正确性;与门限-完全服务模型相比,该模型中心站点的队长和时延均小于门限-完全服务中心站点的队长和时延,具有更高的优先级;与一级完全服务和一级限定(K=2)服务模型相比,区分了优先级,性能分别提升11.7%和14.5%,说明两级服务远好于一级服务;与完全-限定(K=1)两级服务模型相比,增加了发送的数据,减少了等待时间,性能提升13.04%左右,进一步优化了普通站点的性能。 展开更多
关键词 优先级 连续时间 完全-限定(K=2) 平均排队队长 平均时延 服务效率
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稀土离子掺杂NaGdF_(4)下转换发光材料的制备及发光性能研究
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作者 季喜燕 杨坤 《功能材料》 CAS CSCD 北大核心 2024年第11期11090-11095,共6页
选择NaGdF_(4)作为基质材料,以Er^(3+)、Yb^(3+)为掺杂元素,采用水热法制备出了Er^(3+)/Yb^(3+)掺杂的NaGdF_(4)下转换发光材料,通过XRD、SEM、发射光谱、荧光衰减分析等对其进行了表征。结果表明,Er^(3+)/Yb^(3+)的掺杂没有改变NaGdF_... 选择NaGdF_(4)作为基质材料,以Er^(3+)、Yb^(3+)为掺杂元素,采用水热法制备出了Er^(3+)/Yb^(3+)掺杂的NaGdF_(4)下转换发光材料,通过XRD、SEM、发射光谱、荧光衰减分析等对其进行了表征。结果表明,Er^(3+)/Yb^(3+)的掺杂没有改变NaGdF_(4)的晶格结构,未生成新的产物,样品具有较好的纯度,平均粒径尺寸在50~60 nm之间。以380 nm激发光照射样品,发射光谱出现了699,662,563和554 nm的发射峰,分别对应着Er^(3+)离子的^(4)I_(9/2)→^(4)I_(15/2)、^(4)F_(9/2)→^(4)I_(15/2)、^(4)S_(3/2)→^(4)I_(15/2)和^(2)H_(11/2)→^(4)I_(15/2)能级跃迁。随着Yb^(3+)掺杂浓度的增加,近红外光区的发光强度呈先上升后下降趋势,CIE色坐标表明样品的颜色由黄绿光区逐渐向蓝紫光区转变,当n(Er^(3+))∶n(Yb^(3+))=2∶2时,NaGdF_(4)发光材料在可见光区域的发射光谱强度最高。能量传递效率和量子效率随Yb^(3+)浓度的增加而不断增大,当Yb^(3+)的浓度达到6%(摩尔分数)时,样品寿命最低为7.70μs,该掺杂浓度下的NaGdF_(4)具有最高的能量传递效率和量子效率,分别为81.19%和181.19%。 展开更多
关键词 稀土离子 NaGdF_(4) 发光材料 能级跃迁 量子效率
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高光效粳稻新品种龙稻207的品种特性及栽培技术
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作者 王麒 曾宪楠 +2 位作者 孙羽 宋秋来 梁全喜 《黑龙江农业科学》 2024年第12期115-119,共5页
为促进高光效粳稻新品种的推广,本文简要介绍高光效粳稻新品种龙稻207的选育过程、品种特性、产量及其栽培技术要点。龙稻207是黑龙江省农业科学院耕作栽培研究所选育,以母本哈1031、父本东农428采用系谱法选育而成的高光效粳稻新品种。... 为促进高光效粳稻新品种的推广,本文简要介绍高光效粳稻新品种龙稻207的选育过程、品种特性、产量及其栽培技术要点。龙稻207是黑龙江省农业科学院耕作栽培研究所选育,以母本哈1031、父本东农428采用系谱法选育而成的高光效粳稻新品种。2021-2022年区域试验平均产量8534.7 kg·hm^(-2),比对照品种龙稻18增产8.3%;2022年生产试验平均产量为8364.5 kg·hm^(-2),比对照品种龙稻18增产8.7%。2023年,龙稻207获得植物品种权申请号(20231003593);2023年通过黑龙江省审定(审定编号为黑审稻20230013)。该品种生育日数142 d左右,需≥10℃活动积温2700℃左右。通过Fv/Fm值检测龙稻207在大田高光胁迫下能够快速实现光恢复,可以从光抑制值0.283恢复到0.740,该品种能够维持大田下的高光合作用能力。 展开更多
关键词 高光效 粳稻 龙稻207 品种特性
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国家区域医疗中心武汉协和重庆医院电气设计要点
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作者 杨皞 李宇飞 《建筑电气》 2024年第3期56-63,4,共9页
以国家区域医疗中心华中科技大学同济医学院附属协和医院重庆医院(一期工程)为例,对医疗建筑电气设计的以下问题进行分析与探讨:供配电系统设计的变压器安装容量合理性分析、供配电系统可靠性分析、变压器能效等级选择及机房选址等;针... 以国家区域医疗中心华中科技大学同济医学院附属协和医院重庆医院(一期工程)为例,对医疗建筑电气设计的以下问题进行分析与探讨:供配电系统设计的变压器安装容量合理性分析、供配电系统可靠性分析、变压器能效等级选择及机房选址等;针对医疗建筑的电能质量问题提出解决方案;调研同类医疗项目存在的照明光环境问题,设计本项目的物联网智能照明光环境系统;总结本项目光储直柔微网系统设计要点。 展开更多
关键词 医疗建筑 供配电系统 变压器能效等级 ETAP 供电可靠性 电能质量 照明光环境 光储直柔微网
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顺势而为——三星堆博物馆新馆电气设计
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作者 李慧 徐建兵 敖发兴 《建筑电气》 2024年第8期3-10,共8页
三星堆博物馆新馆电气设计以对博物馆展陈最小干预,平衡建筑功能和其他专业需求,兼顾电气装置能源效率为原则,在分析项目前期调研情况和用电需求基础上,从电气机房选址、供配电系统设计、展陈配合、防雷接地系统等方面介绍三星堆博物馆... 三星堆博物馆新馆电气设计以对博物馆展陈最小干预,平衡建筑功能和其他专业需求,兼顾电气装置能源效率为原则,在分析项目前期调研情况和用电需求基础上,从电气机房选址、供配电系统设计、展陈配合、防雷接地系统等方面介绍三星堆博物馆新馆如何根据园区现状、建筑布局、电气系统特点,进行顺势而为的电气设计。 展开更多
关键词 三星堆博物馆 顺势而为 变电所 电气机房选址 能源效率 重心法 平均线路长度法 展陈负荷
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柔性无机电致发光器件及其在智能纺织品上的应用进展 被引量:2
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作者 朱杰 杨群 +7 位作者 陶思轩 周卫冕 崔进 张宁 苏娟 徐丽慧 潘虹 王际平 《丝绸》 CAS CSCD 北大核心 2024年第8期60-69,共10页
柔性无机电致发光器件具有发光效率高、响应速度快、制备成本低、发光稳定等特点,可以实现柔性显示、智能传感等功能,在智能手机、电子皮肤、智能可穿戴等领域有着广泛的应用前景。而纺织材料的柔性、可穿戴性及成熟的加工技术使其成为... 柔性无机电致发光器件具有发光效率高、响应速度快、制备成本低、发光稳定等特点,可以实现柔性显示、智能传感等功能,在智能手机、电子皮肤、智能可穿戴等领域有着广泛的应用前景。而纺织材料的柔性、可穿戴性及成熟的加工技术使其成为柔性电致发光器件的优良载体。柔性无机电致发光器件主要包括硫化锌柔性电致发光器件、钙钛矿基柔性电致发光器件和其他无机发光材料基柔性电致发光器件,其与纺织材料的结合方法主要包括印刷、涂层、层压及编织等。因此,文章从无机电致发光材料出发,对其发展历程、设计思路、制备方法、发光原理及其在纺织品上的应用及存在的问题和面临的挑战进行综述,并对基于电致发光技术的智能可穿戴纺织品应用及发展展开讨论,以更好地推进智能纺织品的发展。 展开更多
关键词 无机电致发光 柔性器件 发光效率 智能纺织品 可穿戴 亮度
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Symmetric Brownian motor subjected to Lévy noise 被引量:1
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作者 贾考 胡兰 聂林如 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期222-227,共6页
In the past few years,attention has mainly been focused on the symmetric Brownian motor(BM)with Gaussian noises,whose current and energy conversion efficiency are very low.Here,we investigate the operating performance... In the past few years,attention has mainly been focused on the symmetric Brownian motor(BM)with Gaussian noises,whose current and energy conversion efficiency are very low.Here,we investigate the operating performance of the symmetric BM subjected to Lévy noise.Through numerical simulations,it is found that the operating performance of the motor can be greatly improved in asymmetric Lévy noise.Without any load,the Lévy noises with smaller stable indexes can let the motor give rise to a much greater current.With a load,the energy conversion efficiency of the motor can be enhanced by adjusting the stable indexes of the Lévy noises with symmetry breaking.The results of this research are of great significance for opening up BM’s intrinsic physical mechanism and promoting the development of nanotechnology. 展开更多
关键词 symmetric Brownian motor average velocity energy conversion efficiency Lévy noise
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基于光效和BP神经网络的LED结温预测研究
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作者 王宸 张军朝 +2 位作者 许并社 张婕 付强 《电子器件》 CAS 2024年第2期496-501,共6页
提出了一种发光效率结合BP神经网络的大功率LED结温预测方法。实验中发现LED的发光效率在结温升高至80℃左右将急剧下降,光效与结温的函数关系发生改变,进而影响了测量精度。针对这一问题,基于发光效率与结温的函数关系,构建实验平台,... 提出了一种发光效率结合BP神经网络的大功率LED结温预测方法。实验中发现LED的发光效率在结温升高至80℃左右将急剧下降,光效与结温的函数关系发生改变,进而影响了测量精度。针对这一问题,基于发光效率与结温的函数关系,构建实验平台,获取发光效率和相应结温的数据,然后通过BP神经网络建立LED结温预测模型。模型所得数据与正向电压法进行对比实验,最大误差为2.1℃,验证了所提方法的可行性,同时所提方法无需考虑LED的内部结构,能够简便,准确地预测大功率LED结温。 展开更多
关键词 大功率LED 发光效率 BP神经网络 结温
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预住院管理对缩短平均住院日的影响
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作者 周清 廖伟锋 吴碧红 《现代医院》 2024年第9期1423-1425,共3页
湖南省某大型综合性三级公立医院作为省内首批预住院试点单位,率先在床位集约式统筹管理基础上探索预住院管理模式,通过简化预住院流程、实施精细化服务、打通专用检查通道、运用信息化手段实行预住院患者全流程管理等措施,保障预住院... 湖南省某大型综合性三级公立医院作为省内首批预住院试点单位,率先在床位集约式统筹管理基础上探索预住院管理模式,通过简化预住院流程、实施精细化服务、打通专用检查通道、运用信息化手段实行预住院患者全流程管理等措施,保障预住院工作的开展。通过实践,外科病房平均住院日显著下降,以乳腺外科、耳鼻喉科为例,实施先后对比,平均住院日分别降低4.41、3.29 d。文章深入探讨了预住院管理模式对缩短平均住院日的影响,为国内大型医院在提升运营效率、缓解床位紧张等方面提供参考,为践行改善就医感受提升患者体验主题活动、提升患者诊前体验提供思路。 展开更多
关键词 预住院 平均住院日 医院运营效率 患者诊前体验
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空间电场作用下聚合物形貌演变及光学性能研究
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作者 刘少琛 刘学清 《塑料工业》 CAS CSCD 北大核心 2024年第5期160-168,共9页
聚合物薄膜表面的微纳结构具有独特的光学性能,在柔性电子和显示器件中有潜在的应用前景。而空间电场是构建表面形貌的有效手段。本研究以光固化聚氨酯(PU)为对象,用comsol软件模拟了空间电场作用下PU预聚体的介电常数、黏度、表面张力... 聚合物薄膜表面的微纳结构具有独特的光学性能,在柔性电子和显示器件中有潜在的应用前景。而空间电场是构建表面形貌的有效手段。本研究以光固化聚氨酯(PU)为对象,用comsol软件模拟了空间电场作用下PU预聚体的介电常数、黏度、表面张力、电压对形貌的影响。进一步通过实验,在600 V空间电场制备出高度为327μm的柱状阵列微结构PU透明薄膜。该薄膜在380~750 nm波段,其出光效率提升了18%,且微结构对色温没有影响。 展开更多
关键词 空间电场 聚氨酯薄膜 微结构 仿真模拟 出光效率
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场协同扭转螺杆混合性能模拟与实验
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作者 代瑞 黄士争 +4 位作者 潘威 朱家威 曾宪奎 杨卫民 鉴冉冉 《合成橡胶工业》 CAS 2024年第6期451-457,共7页
螺杆混合能力是影响聚合物挤出过程中塑化质量和均匀性的重要因素。使用Polyflow软件,采用数值模拟的方法对创新提出的场协同扭转螺杆在不同转速下的混合性能进行了模拟分析,同时以三元乙丙橡胶为原料,采用扭转挤出技术结合混合效率、... 螺杆混合能力是影响聚合物挤出过程中塑化质量和均匀性的重要因素。使用Polyflow软件,采用数值模拟的方法对创新提出的场协同扭转螺杆在不同转速下的混合性能进行了模拟分析,同时以三元乙丙橡胶为原料,采用扭转挤出技术结合混合效率、平均停留时间、分布指数、炭黑分散度和粒径分布等参数对常规螺杆与场协同扭转螺杆的混合能力进行了对比实验研究。结果表明,设置有扭转元件的场协同扭转螺杆的混合效率更高、停留时间分布更长,改善了整个体系的混合效果,其中螺杆F对物料的混合效果最优;所得实验结果与模拟结果一致,证明了场协同扭转螺杆具有强化混合的特性。 展开更多
关键词 场协同扭转螺杆 混合性能 混合效率 平均停留时间 分布指数 炭黑分散度 粒径分布
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