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An Objective Approach to Generating Multi-Physics Ensemble Precipitation Forecasts Based on the WRF Model

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Journal of Meteorological Research 2020年第3期34卷 601-620页

作者： Chenwei SHEN Qingyun DUAN Wei GONG yanjun gan Zhenhua DI Chen WANG Shiguang MIAO State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875 State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering and College of Hydrology&Water Resources Hohai UniversityNanjing 210098 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650 Institute of Urban Meteorology China Meteorological AdministrationBeijing 100081

Selecting proper parameterization scheme combinations for a particular application is of great interest to the Weather Research and Forecasting(WRF)model *** study aims to develop an objective method for identifying a set of scheme combinations to form a multi-physics ensemble suitable for short-range precipitation forecasting in the Greater Beijing *** ensemble is created by using statistical techniques and some *** initial sample of 90 scheme combinations was first generated by using Latin hypercube sampling(LHS).Then,after several rounds of screening,a final ensemble of 40 combinations were *** ensemble forecasts generated for both the training and verification cases using these combinations were evaluated based on several verification metrics,including threat score(TS),Brier score(BS),relative operating characteristics(ROC),and ranked probability score(RPS).The results show that TS of the final ensemble improved by 9%-33%over that of the initial *** reliability was improved for rain≤10 mm day^-1,but decreased slightly for rain>10 mm day^-1 due to insufficient *** resolution remained about the *** final ensemble forecasts were better than that generated from randomly sampled scheme *** results suggest that the proposed approach is an effective way to select a multi-physics ensemble for generating accurate and reliable forecasts.

关键词： ensemble precipitation forecast Weather Research and Forecasting(WRF)model multi-physics verification bootstrapping

Biodegradable,strong,and clear wood package for plastic alternative

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Nano Research 2024年第9期17卷 8531-8541页

作者： Jianfu Tang Xueqin Fan Haozhou Huang Xiaofei Dong Xueqi Li Peiru Wang Ran Yin yanjun Xie Jian Li gang Tan Zhenqian Pang Wentao gan Key Laboratory of Bio-based Material Science&Technology(Ministry of Education) Northeast Forestry UniversityHarbin 150040China Department of Architecture College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310027China Smart Materials for Architecture Research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China Heilongjiang Key Laboratory of Complex Traits and Protein Machines in Organisms Northeast Forestry UniversityHarbin 150040China

Using biodegradable material derived from renewable resources as petroleum-based plastics replacement is a promising way towards sustainable ***,the insufficient mechanical properties and complex manufacturing process of bioplastics still need to be improved for high-quality food ***,we report a top-down strategy to transform natural wood into a clear wood packaging film through scalable delignification and polyvinyl alcohol(PVA)*** wood packaging film demonstrates a laminated structure with completely collapsed cell walls and PVA intertwined together after energy-saving air drying,resulting in high light transmittance with low haze,good mechanical performance,and high barrier performance for oxygen and water *** dynamics simulations reveal the underlying fracture mechanism between cellulose and PVA,which effectively enhances the Young’s modulus and strength of the wood packaging *** findings contribute to the development of biodegradable and strong packaging materials,as well as other food-related applications,using sustainable wood.

关键词： wood food package mechanical enhancement plastic replacement biodegradability

Control of gan inverted pyramids growth on c-plane patterned sapphire substrates

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Journal of Semiconductors 2024年第6期45卷 92-96页

作者： Luming Yu Xun Wang Zhibiao Hao Yi Luo Changzheng Sun Bing Xiong yanjun Han Jian Wang Hongtao Li Lin gan Lai Wang Beijing National Research Center for Information Science and Technology Department of Electronic EngineeringTsinghua UniversityBei-jing 100084China Center for Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Growth of gallium nitride(gan)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar *** this work,gan inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff *** competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of gan.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in gan inverted *** the other hand,gan inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat.

关键词： inverted pyramids gan MOVPE crystal growth competition model

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肉牛养殖疫病防控技术要点

畜牧兽医科学（电子版） 2022年第9期 116-118页

作者：甘艳君四川省渠县动物疫病预防控制中心四川达州635200

开展高水平的规范化肉牛养殖工作,需增强肉牛养殖时的疫病防控工作,减少养殖过程中的疫病发生率。在肉牛养殖场若是发生疫病传播的情况,不但会严重影响到肉牛的正常成长,甚至还会出现肉牛死亡的情况,给养殖者带来不必要的经济损失。因此... 详细信息

开展高水平的规范化肉牛养殖工作,需增强肉牛养殖时的疫病防控工作,减少养殖过程中的疫病发生率。在肉牛养殖场若是发生疫病传播的情况,不但会严重影响到肉牛的正常成长,甚至还会出现肉牛死亡的情况,给养殖者带来不必要的经济损失。因此,在肉牛养殖日常工作中,增强对疫病的防控是很有必要的。该文主要剖析肉牛养殖工作中的疫病防控和发展前景,以期为有关养殖工作人员提高疫病防控能力,肉牛养殖工作更加规范、健康,为消费者提供更加安全可靠的牛肉类产品。

关键词：肉牛养殖疫病防控发展前景

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马达汉国内研究综述

天水师范学院学报 2016年第1期36卷 104-109页

作者：高彦军兰州大学历史文化学院甘肃兰州730020

芬兰探险家马达汉于1906年从中亚来到中国西北考察,他所拍摄的照片、绘制的地图和开展的民族调查等给晚清新疆、甘肃等地的研究留下了丰富而宝贵的资料。学界已经对此进行了大量的研究,相关成果主要集中在对马达汉日记的解读以及结合其... 详细信息

芬兰探险家马达汉于1906年从中亚来到中国西北考察,他所拍摄的照片、绘制的地图和开展的民族调查等给晚清新疆、甘肃等地的研究留下了丰富而宝贵的资料。学界已经对此进行了大量的研究,相关成果主要集中在对马达汉日记的解读以及结合其日记研究晚清西北地区少数民族、风土人情、地方官吏等方面。回顾近20年来国内学界对马达汉的研究很有必要,通过梳理发现在研究中取得的成就和存在的不足。

关键词：马达汉新疆考察

Photonics-assisted THz wireless communication enabled by wide-bandwidth packaged backilluminated modified uni-traveling-carrier photodiode

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Opto-Electronic Science 2024年第7期3卷 20-29页

作者： Yuxin Tian Boyu Dong Yaxuan Li Bing Xiong Junwen Zhang Changzheng Sun Zhibiao Hao Jian Wang Lai Wang yanjun Han Hongtao Li Lin gan Nan Chi Yi Luo Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China Flexible Intelligent Optoelectronic Device and Technology Center Institute of Flexible Electronics Technology of THUJiaxing 314000China

This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless *** optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation *** passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide *** packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 *** wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.

关键词： modified uni-traveling-carrier photodiode integrated bias-tee E-plane probe flat frequency response high saturation power WR-5 output THz wireless communications

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荆门市竹皮河的生态补水方案研究

人民长江 2010年第10期41卷 83-85,97页

作者：张洪斌李兰甘衍军武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

荆门市竹皮河水体污染严重,影响市区环境的同时,也影响了汉江的水质。对从漳河水库调水改善竹皮河水环境的作用进行了研究。采用了单因子水质参数标准指数法确定水体的主要污染物后,选取一维河道稳态水质模型及均匀混合水质模型研究了... 详细信息

荆门市竹皮河水体污染严重,影响市区环境的同时,也影响了汉江的水质。对从漳河水库调水改善竹皮河水环境的作用进行了研究。采用了单因子水质参数标准指数法确定水体的主要污染物后,选取一维河道稳态水质模型及均匀混合水质模型研究了不同流量的生态补水对竹皮河水质的影响,从而确定最佳的生态补水量,并得到此补水量下河流的纳污能力。

关键词：生态补水污染物浓度纳污能力水环境

基于多特征符号聚合近似和层次聚类的户变关系识别方法

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电力系统自动化 2024年第3期48卷 133-141页

作者：周赣茅欢冯燕钧华济民曾瑛东南大学电气工程学院江苏省南京市210096 国网江苏省电力有限公司无锡供电分公司江苏省无锡市214000 广东电网有限责任公司广东省广州市510600

针对低压配电台区拓扑档案中可能存在的户变关系异常问题,文中提出了一种基于多特征符号聚合近似(MF-SAX)和层次聚类的户变关系识别方法。首先,运用符号聚合近似表达方法将用户电压时间序列转化为字符串序列,并引入电压波动系数和电压... 详细信息

针对低压配电台区拓扑档案中可能存在的户变关系异常问题,文中提出了一种基于多特征符号聚合近似(MF-SAX)和层次聚类的户变关系识别方法。首先,运用符号聚合近似表达方法将用户电压时间序列转化为字符串序列,并引入电压波动系数和电压变化趋势两个附加参数对其特征表达进行强化。然后,基于编辑距离生成用户电压曲线相似性矩阵,并结合层次聚类算法实现户变关系的识别。最后,实际算例结果表明,提出的方法相比于现有方法准确率更高,误报更少,能直接应对数据缺失的情况,且具有更高的效率。

关键词：低压配电台区户变关系层次聚类拓扑识别电压曲线相似性

健康教育路径在甲状腺切除术患者围手术期的应用

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辽宁医学院学报 2014年第2期35卷 80-82页

作者：卢艳君钱学贞甘艳军深圳市松岗人民医院广东深圳518105

目的探讨健康教育路径在甲状腺切除术患者围手术期的临床应用效果。方法 114例甲状腺切除术围手术期患者随机分为观察组(n=57)与对照组(n=57),对照组给予常规甲状腺手术护理,观察组在对照组基础上实施健康教育路径,对比两组患者住院时... 详细信息

目的探讨健康教育路径在甲状腺切除术患者围手术期的临床应用效果。方法 114例甲状腺切除术围手术期患者随机分为观察组(n=57)与对照组(n=57),对照组给予常规甲状腺手术护理,观察组在对照组基础上实施健康教育路径,对比两组患者住院时间、住院费用、疾病知识掌握情况及对护理服务满意度。结果观察组住院时间显著短于对照组(P<0.01),住院费用显著低于对照组(P<0.05),疾病知识掌握率及对护理服务满意率均显著高于对照组(P<0.01)。结论健康教育路径可提高甲状腺切除术围手术期患者对疾病的认识及对护理服务满意率,促进术后康复,节省医疗资源,值得推广应用。

关键词：健康教育路径甲状腺切除术围手术期