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SIL1 improves cognitive impairment in APP23/PS45 mice by regulating amyloid precursor protein processing and Aβ generation
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作者 Qunxian Wang Yanshuang Jiang +5 位作者 Zijun Meng Xiangjun Dong Dongjie Hu Liangye Ji Weihui Zhou Weihong Song 《Zoological Research》 SCIE CSCD 2024年第4期845-856,共12页
SIL1,an endoplasmic reticulum(ER)-resident protein,is reported to play a protective role in Alzheimer’s disease(AD).However,the effect of SIL1 on amyloid precursor protein(APP)processing remains unclear.In this study... SIL1,an endoplasmic reticulum(ER)-resident protein,is reported to play a protective role in Alzheimer’s disease(AD).However,the effect of SIL1 on amyloid precursor protein(APP)processing remains unclear.In this study,the role of SIL1 in APP processing was explored both in vitro and in vivo.In the in vitro experiment,SIL1 was either overexpressed or knocked down in cells stably expressing the human Swedish mutant APP695.In the in vivo experiment,AAV-SIL1-EGFP or AAV-EGFP was microinjected into APP23/PS45 mice and their wild-type littermates.Western blotting(WB),immunohistochemistry,RNA sequencing(RNA-seq),and behavioral experiments were performed to evaluate the relevant parameters.Results indicated that SIL1 expression decreased in APP23/PS45 mice.Overexpression of SIL1 significantly decreased the protein levels of APP,presenilin-1(PS1),and C-terminal fragments(CTFs)of APP in vivo and in vitro.Conversely,knockdown of SIL1 increased the protein levels of APP,β-site APP cleavage enzyme 1(BACE1),PS1,and CTFs,as well as APP mRNA expression in 2EB2 cells.Furthermore,SIL1 overexpression reduced the number of senile plaques in APP23/PS45 mice.Importantly,Y-maze and Morris Water maze tests demonstrated that SIL1 overexpression improved cognitive impairment in APP23/PS45 mice.These findings indicate that SIL1 improves cognitive impairment in APP23/PS45 mice by inhibiting APP amyloidogenic processing and suggest that SIL1 is a potential therapeutic target for AD by modulating APP processing. 展开更多
关键词 Alzheimer’s disease sIL1 APP processing Cognitive impairment
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贝托司汀手性中间体(S)-CPMA整细胞催化合成工艺研究
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作者 古永红 王德林 +2 位作者 饶振辉 龚大春 肖玲玲 《三峡大学学报(自然科学版)》 CAS 北大核心 2024年第5期105-112,共8页
针对不同条件对贝托司汀手性中间体(S)-CPMA的整细胞催化合成影响,进行单因素实验和正交设计优化研究.首先从耐热克鲁维酵母突变株SXBP-02预处理方式、不同催化反应介质、pH、底物质量浓度、温度、时间、催化剂用量、补料次数等8个方面... 针对不同条件对贝托司汀手性中间体(S)-CPMA的整细胞催化合成影响,进行单因素实验和正交设计优化研究.首先从耐热克鲁维酵母突变株SXBP-02预处理方式、不同催化反应介质、pH、底物质量浓度、温度、时间、催化剂用量、补料次数等8个方面进行考察,揭示其中pH、底物质量浓度、补料次数和催化剂用量4个因素对(S)-CPMA催化效率的影响较大;进一步对其进行正交优化,得出最佳工艺条件:在pH8的PEG4000双水相体系中,底物质量浓度为6g/L、补料次数为4次、催化剂用量为3g/L,温度为40℃条件下反应36h,可得到(S)-CPMA产率为88.1%,对映选择性在98.5%以上,4个因素对(S)-CPMA收率的影响主次顺序依次为补料次数>pH>催化剂用量>底物质量浓度,其中补料次数、pH为显著性影响因素,与优化前相比,底物质量浓度提高3倍,产率提高了6%. 展开更多
关键词 整细胞催化 (s)-CPMA 工艺 优化
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基于D-S证据理论改进AHP-熵权的流域洪涝灾害评估研究
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作者 苑希民 高瑞梅 +1 位作者 田福昌 侯玮 《水资源与水工程学报》 CSCD 北大核心 2024年第1期9-16,共8页
考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小... 考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小清河流域洪涝灾害风险空间分布情况。结果表明:小清河流域洪涝灾害风险总体上表现出南低北高的趋势,其中高风险区和较高风险区分别占流域面积的8.7%和14.3%,主要分布在小清河干流以及主要支流两岸。所得评估结果同“利奇马”台风发生期间实际洪灾风险分布情况一致,对比证明基于D-S证据理论的改进AHP-熵权法优于AHP和熵权法,可为小清河流域防洪减灾决策提供依据。 展开更多
关键词 D-s证据理论 AHP 熵权法 洪涝灾害评估 小清河流域
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Strategies for Improving the Effectiveness of Professional Practice for Full-Time Professional Master Degree Postgraduate in Mineral Processing Engineering 被引量:1
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作者 Jiushuai Deng Juan Hu +3 位作者 Zhiqiang Xu Weidong Wang Zhongyi Bai Tingting Hu 《Journal of Contemporary Educational Research》 2023年第1期27-32,共6页
In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,in... In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,including insufficient time for practice,low management level,inadequate implementation of the double-supervisor system,and poor results of professional practice,has reduced the effectiveness of professional practice.In view of the aforementioned problems and the characteristics of the discipline,this paper proposes several strategies for improving the effectiveness of professional practice for postgraduates in mineral processing engineering. 展开更多
关键词 Mineral processing engineering FULL-TIME Application-oriented Master’s degree Professional practice
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Clinical Utilization of Nursing Process in Improving Patient’s Outcome and Its Associated Factors: A Cross-Sectional Study among Nurses and Midwives Working at Njombe Regional Referral Hospital, Tanzania
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作者 Evaristus P. Makota Winfred P. Kyambile +2 位作者 Vinogelaki Seif Ashery Mwalukolo Emmanuel Ulomi 《Open Journal of Nursing》 2023年第8期537-550,共14页
Background: Improvement of patient care in any hospital depends primarily on the quality of nursing care. Nursing care is enhanced by the nursing process, which outlines the nursing activities to be provided for a pat... Background: Improvement of patient care in any hospital depends primarily on the quality of nursing care. Nursing care is enhanced by the nursing process, which outlines the nursing activities to be provided for a patient. Methods and Materials: A cross sectional design employing quantitative methods was conducted in Njombe RRH in December 2021. Quantitative data were collected from nurses and midwives from all wards by simple random sampling techniques using a sample-size calculator. SPSS version 26.0 was used to analyse data whereby a p-value of 0.05 was considered a decision mark for the significance of the result;Chi-square and Logistic regression respectively were used to find out the association and its strength between variables. Result: Majority of the respondents, 41 (85.4%), had inadequate knowledge and 33 (68.8%) found them people with a negative attitude to the nursing process. Significantly, there is an association between knowledge and clinical utilization (AOR 2.24;95% CI: 1.6 - 2.5;P 0.04), attitude and clinical utilization (AOR 4.32;95% CI: 1.8 - 3.7;P Conclusion: A knowledge gap in relation to the utilization of the nursing process and a negative attitude were noted to be associated significantly with the utilization of the nursing process among nurses and midwives. It is recommended on-job training, supportive supervision, and Value Clarification and Attitude Transformation (VCAT) are the best interventions to address the knowledge gap and negative attitudes respectively. 展开更多
关键词 Clinical Utilization Knowledge Attitude Patient’s Outcome Nursing process
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Eagle’s Syndrome: A Case Report of a Bilateral Elongated Styloid Process
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作者 Mahammad Davudov Surayya Isgandarova Parvin Hasanova 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第6期405-410,共6页
Eagle’s syndrome is symptomatic of the styloid process (SP) elongation or calcification of the stylohyoid and stylomandibular ligaments. As a result of Eagle’s various studies, 4 out of every 100 patients showed tha... Eagle’s syndrome is symptomatic of the styloid process (SP) elongation or calcification of the stylohyoid and stylomandibular ligaments. As a result of Eagle’s various studies, 4 out of every 100 patients showed that the styloid process was long. However only 4% of these cases are symptomatic [1]. Surgical traumas such as tonsillectomy or stylomandibular chronic irritation of the ligament, proc. of styloideusosteitis, ossifying periosteitis, tendinitis or mucositis why could it be [2]. The main symptoms are facial pain, dysphagia, sore throat, earache and headache. It may be unilateral or bilateral. The styloid process can be shortened through an intraoral or external approach. The case of Eagle syndrome in a 39-year-old female patient who was diagnosed to have bilateral elongated. 展开更多
关键词 Eagle’s syndrome Throat Pain Elongated styloid process Extraoral Approach
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Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation
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作者 Haixu Li Haobo He +7 位作者 Tiannan Jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong Xue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期169-181,共13页
S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB... S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)degradation.The effects of two different mixing routes were identified on the MB degradation performance.Particularly,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with Co-S.Furthermore,the degradation parameters,including pH and MOF-AEP dosage,were investigated.Finally,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB. 展开更多
关键词 advanced oxidation process alcohol solvent evaporation hydrogen bond s and Co co-doped carbon catalysts wastewater remediation
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2022年四川泸定M_(S)6.8地震震源破裂过程及强地面运动模拟
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作者 舒甜甜 罗艳 朱音杰 《地震》 CSCD 北大核心 2024年第1期19-36,共18页
首先,利用区域宽频带波形拟合,反演了2022年泸定M_(S)6.8地震序列主震和部分余震的震源机制解和震源深度;其次,基于有限断层模型反演方法,使用区域宽频带波形数据反演了此次泸定地震震源破裂过程,并根据得到的震源破裂模型计算了峰值地... 首先,利用区域宽频带波形拟合,反演了2022年泸定M_(S)6.8地震序列主震和部分余震的震源机制解和震源深度;其次,基于有限断层模型反演方法,使用区域宽频带波形数据反演了此次泸定地震震源破裂过程,并根据得到的震源破裂模型计算了峰值地面速度(PGV)分布。结果显示,此次地震矩心深度为6.0 km,是一个典型的高角度左旋走滑地震。震源破裂传播方向主要沿断层走向约165°向东南方向传播,由深部震源起始破裂点向浅部扩展,并破裂到地表,地表破裂主要分布在磨西到猛虎岗一带,长度约16 km。震源破裂过程持续时间约20 s,能量主要集中在前15 s内释放。地震释放的标量地震矩为1.07×10^(19)N·m,约等于矩震级M_(W)6.62。地震主体破裂发生在3~6 s之间,最大滑动量达到1.8 m,位于震中东南方向深度约10 km处。除此之外,在震中西北方向深度11 km处和震中东南方向深度18 km处分别发生两个次级破裂,滑动量大约在0.6~1.0 m。主体破裂的破裂长度约20 km,两个次级破裂的长度分别约为4 km和8 km。使用该震源破裂模型计算得到了PGV分布,PGV分布以震中为中心沿断层走向两侧扩散,其长轴与地震断层走向一致,呈NW向,极震区PGV为200~360 cm/s,地震烈度区内受灾严重的村镇均位于极震区。 展开更多
关键词 2022年泸定M_(s)6.8地震 震源机制解 震源破裂过程 峰值地面速度
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基于外部气相沉积的S+C+L波段低色散斜率大有效面积非零色散位移光纤的设计与制备
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作者 查健江 王元达 +3 位作者 何学荣 侯伟 王敬胜 文建湘 《光子学报》 EI CAS CSCD 北大核心 2024年第2期52-63,共12页
针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第... 针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第一芯层的半径比,探究了其对光纤衰减、色散斜率和有效面积等参数的影响。研究发现,当第一芯层的相对折射率逐渐增大且第二芯层与第一芯层半径比逐渐减小时,零色散波长和有效面积逐渐减小。当第一芯层的相对折射率在0.52%~0.53%,芯层半径比在2.6~2.7时,光纤的有效面积接近70μm^(2),零色散波长在1420 nm附近,在1550 nm波段的色散系数大于8 ps·nm^(-1)·km^(-1),色散斜率为0.059 ps·nm^(-2)·km^(-1),可以较好地抑制传输过程中光非线性效应,满足长途干线网与城域网的使用要求。 展开更多
关键词 光纤通信 非零色散位移光纤 外部气相沉积工艺 s%PLUs%C%PLUs%L波段 低色散斜率 大有效面积 波分复用
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Digital Disparities:How Artificial Intelligence Can Facilitate Anti-Black Racism in the U.S.Healthcare Sector
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作者 Anthony Victor Onwuegbuzia 《International Relations and Diplomacy》 2024年第1期40-50,共11页
This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to en... This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to enhance healthcare outcomes and reduce disparities,there is a growing concern that these technologies may inadvertently/advertently exacerbate existing racial inequalities.Focusing specifically on the experiences of Black patients,this research investigates how the following AI components:medical algorithms,machine learning,and natural learning processes are contributing to the unequal distribution of medical resources,diagnosis,and health care treatment of those classified as Black.Furthermore,this review employs a multidisciplinary approach,combining insights from computer science,medical ethics,and social justice theory to analyze the mechanisms through which AI systems may encode and reinforce racial biases.By dissecting the three primary components of AI,this paper aims to present a clear understanding of how these technologies work,how they intersect,and how they may inherently perpetuate harmful stereotypes resulting in negligent outcomes for Black patients.Furthermore,this paper explores the ethical implications of deploying AI in healthcare settings and calls for increased transparency,accountability,and diversity in the development and implementation of these technologies.Finally,it is important that I prefer the following paper with a clear and concise definition of what I refer to as Anti-Black racism throughout the text.Therefore,I assert the following:Anti-Black racism refers to prejudice,discrimination,or antagonism directed against individuals or communities of African descent based on their race.It involves the belief in the inherent superiority of one race over another and the systemic and institutional practices that perpetuate inequality and disadvantage for Black people.Furthermore,I proclaim that this form of racism can be manifested in various ways,such as unequal access to opportunities,resources,education,employment,and fair treatment within social,economic,and political systems.It is also pertinent to acknowledge that Anti-Black racism is deeply rooted in historical and societal structures throughout the U.S.borders and beyond,leading to systemic disadvantages and disparities that impact the well-being and life chances of Black individuals and communities.Addressing Anti-Black racism involves recognizing and challenging both individual attitudes and systemic structures that contribute to discrimination and inequality.Efforts to combat Anti-Black racism include promoting awareness,education,advocacy for policy changes,and fostering a culture of inclusivity and equality. 展开更多
关键词 Bias in algorithms Racial disparities in U.s.healthcare Discriminatory healthcare practices Black patient outcomes Automated decision-making and racism Machine Learning Natural language processing
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A Historical Review of the Development of Women’s Higher Education in China (1908-2020): Stages, Explanations, and Trends
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作者 TIAN Fen ZHENG Yaqian Ray Taheri 《Sociology Study》 2024年第1期39-53,共15页
The development of women’s higher education in China can be divided into four stages:emergence(1908-1948);foundation(1949-1976);accelerating development(1977-2008);and the qualitative leap(2009-2020).This work consid... The development of women’s higher education in China can be divided into four stages:emergence(1908-1948);foundation(1949-1976);accelerating development(1977-2008);and the qualitative leap(2009-2020).This work considers the principal institutional mechanisms that contributed to this development.First,flexibly planned parenthood gradually promoted gender equality and openness in society facilitated by systematic“awards,grants,and loans”initiatives to support women’s higher education economically.Second,compulsory education ensured that left-out and migrant children had access to higher education.Third,effective connectivity across different education types bridged education gaps between those with different levels of education.Fourth,China made great efforts to invite and integrate international experiences that promoted the development of women’s higher education.Looking beyond these achievements,we also discuss the future trends of women’s higher education in China. 展开更多
关键词 Chinese higher education women’s higher education educational equity development process
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浅析国家药监局加入药品检查合作计划(PIC/S)中广东药监面临的形势与发展展望
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作者 马骏 洪建文 +1 位作者 吴群悦 方维 《中国食品药品监管》 2024年第5期114-121,共8页
国家药监局加入药品检查合作计划(PIC/S)的进程已经进入正式申请阶段,这将加速推动我国药品监管体系国际化现代化发展。本文简要介绍了PIC/S的相关情况,梳理了国家药监局加入该组织的主要进程以及国内近年来在药品GMP检查体系和相关能... 国家药监局加入药品检查合作计划(PIC/S)的进程已经进入正式申请阶段,这将加速推动我国药品监管体系国际化现代化发展。本文简要介绍了PIC/S的相关情况,梳理了国家药监局加入该组织的主要进程以及国内近年来在药品GMP检查体系和相关能力建设方面的工作进展,展望了该形势下广东省药监局联合港澳地区协同推进药品监管能力建设、凝聚自身实践经验、助力国家药品监管和药品产业发展的工作脉络。 展开更多
关键词 药品检查合作计划(PIC/s) 概况 加入进程 面临形势 发展展望
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级间分离S形分离钢索高速分离敏感因素分析
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作者 董瑞涛 林三春 +2 位作者 荀飞 刘金峰 付继伟 《导弹与航天运载技术(中英文)》 CSCD 北大核心 2024年第2期7-10,共4页
级间分离S形分离钢索结构复杂,高速分离过程涉及大变形、复杂非线性接触等问题,其动态变形及力学特性分析是工程设计的难点之一。基于Abaqus建立S形分离钢索动态分离仿真模型,分析了S形分离钢索高速分离动态变形过程及力学特性,并通过... 级间分离S形分离钢索结构复杂,高速分离过程涉及大变形、复杂非线性接触等问题,其动态变形及力学特性分析是工程设计的难点之一。基于Abaqus建立S形分离钢索动态分离仿真模型,分析了S形分离钢索高速分离动态变形过程及力学特性,并通过地面试验进一步验证建模方法的正确性。研究了S形分离钢索长度、截面直径、拖尾长度、分离速度等多种敏感因素的影响,对工程实际具有一定的指导意义。 展开更多
关键词 级间分离 s形分离钢索 高速分离 变形过程 力学特性
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基于ADS-B与Mode-SEHS联合观测的民航空域风场重建方法
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作者 陈敏 王浩楠 +1 位作者 陈万通 任诗雨 《国外电子测量技术》 2024年第6期102-109,共8页
准确实时的风场数据对保障民航飞行安全有着重要作用,针对风场的精确重构问题,提出了一种基于飞行器监测数据的风场重建方法。旨在利用广播式自动相关监视和S模式增强型监视联合观测数据计算空域内的风观测值,并结合机器学习中的高斯过... 准确实时的风场数据对保障民航飞行安全有着重要作用,针对风场的精确重构问题,提出了一种基于飞行器监测数据的风场重建方法。旨在利用广播式自动相关监视和S模式增强型监视联合观测数据计算空域内的风观测值,并结合机器学习中的高斯过程回归模型,利用时间和空间上离散的风观测值进行模型训练,完整重建目标空域风场。实验结果表明,重建的风场风速的平均绝对误差为2.72m/s,相对误差为8.21%,风向的平均绝对误差为3.66°,证明了方法能够快速地完成准确实时的风场重建。 展开更多
关键词 广播式自动相关监视 s模式增强型监视 高斯过程回归 风场重建
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基于AHP法与SBE法的郑州北龙湖湿地公园植物景观评价
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作者 刘樱园 李帅 +1 位作者 吴铮 王鹏飞 《林业调查规划》 2024年第6期68-75,共8页
以郑州市北龙湖湿地公园为调研对象,选取30个植物景观样地,综合运用AHP法和SBE法对调查样地进行评价。结果表明,准则层权重生态效益B_(1)(0.5889)>景观美学B_(2)(0.2519)>游憩服务B_(3)(0.1593);植物景观质量综合评价结果,Ⅰ级植... 以郑州市北龙湖湿地公园为调研对象,选取30个植物景观样地,综合运用AHP法和SBE法对调查样地进行评价。结果表明,准则层权重生态效益B_(1)(0.5889)>景观美学B_(2)(0.2519)>游憩服务B_(3)(0.1593);植物景观质量综合评价结果,Ⅰ级植物景观样地有9个,占样地总数的30%,Ⅱ级植物景观样地有15个,占比50%,Ⅲ级植物景观样地有6个,占比20%;SBE评价法的高分植物景观与景观美学程度呈正相关;利用Kendall′s W协和系数对AHP法和SBE法的评价结果进行一致性检验,渐进显著性为0.008<0.05,两种评价方法具有高度一致性。提出增加彩叶植物协调植物景观与周围环境的关系,改善水生植物群落结构的稳定性等优化湿地公园景观空间建议。 展开更多
关键词 植物景观评价 AHP层次分析法 sBE美景度评价法 Kendall′s W协和系数检验 郑州北龙湖湿地公园
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基于B/S架构的办公管理系统设计与开发
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作者 张丹丹 李弘 《铁路通信信号工程技术》 2024年第9期44-48,106,共6页
结合铁路办公业务需求设计开发基于B/S架构的办公管理系统,通过对系统功能和业务流程进行分析,并集成Activiti流程引擎实现关键业务流程办理。该系统可促进业务高效办理,提升员工协同工作能力,提高铁路企业的运转效率,实现办公自动化。
关键词 B/s架构 办公管理系统 流程引擎 办公自动化
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Box-Behnken法优化20(S)原人参二醇微囊工艺研究
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作者 刘晴 韩晓冉 +4 位作者 纪忠娟 司佳 董聪 程祥 李海燕 《特产研究》 2024年第4期143-149,共7页
为优化20(S)-PPD微囊的制备工艺。本研究先通过单因素试验,确定对20(S)-PPD微囊的制备有显著影响的三个因素,分别为转速、加水体积及壁芯比,然后将三个因素分别设置不同的水平,采用Box-Behnken响应面法对制备工艺进行优化,应用Design-Ex... 为优化20(S)-PPD微囊的制备工艺。本研究先通过单因素试验,确定对20(S)-PPD微囊的制备有显著影响的三个因素,分别为转速、加水体积及壁芯比,然后将三个因素分别设置不同的水平,采用Box-Behnken响应面法对制备工艺进行优化,应用Design-Expert 10软件分析试验结果。试验结果表明,20(S)-PPD微囊的最佳制备工艺为壁材比芯材为1.17,即2 g:1.72 g,加水量为74 mL,搅拌分散转速为209 r/min,优化后的制备工艺制备的微囊包封率可达51.05%,与预测值52.77%相接近,且微囊颗粒圆整,大小均匀。运用单因素实验结合Box-Behnken响应面法优化20(S)-PPD的制备工艺,经试验证明后显示结果准确可靠,可行。 展开更多
关键词 20(s)-原人参二醇 微囊 制备工艺 Box-Behnken响应面法
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一种国外铁路货车用S型侧架铸造工艺设计与应用
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作者 李卫国 樊超 +4 位作者 张挨元 王虎明 宝喜庆 马彦伟 刘跃辉 《铸造工程》 2024年第S01期38-41,共4页
根据S型侧架产品的技术要求和结构特点,进行了铸造工艺设计。生产时采用底注开放式浇注系统,利用ProCAST铸造仿真技术对铸造工艺进行了模拟优化,并在铸件较大热节处增放发热保温冒口套进行补缩。按照优化后的铸造工艺试制生产了侧架铸件... 根据S型侧架产品的技术要求和结构特点,进行了铸造工艺设计。生产时采用底注开放式浇注系统,利用ProCAST铸造仿真技术对铸造工艺进行了模拟优化,并在铸件较大热节处增放发热保温冒口套进行补缩。按照优化后的铸造工艺试制生产了侧架铸件,成功获得合格的铸件产品。 展开更多
关键词 s型侧架 铸造工艺 补缩 模拟
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基于云D-S证据理论的极端天气下电力系统应急能力评判
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作者 王建楠 李元良 +5 位作者 温晓寒 赖元威 卢军严 郑宇琦 何青 郭梽炜 《气象研究与应用》 2024年第1期42-48,共7页
以提高应对极端天气下电力系统突发事件能力为目标,将电力系统应急能力作为研究对象,提出基于云模型和证据理论融合的评估算法。采用层次分析法和熵值法相结合的方法确定应急指标权重,运用云模型做为基础对电力系统应急能力进行评估,以... 以提高应对极端天气下电力系统突发事件能力为目标,将电力系统应急能力作为研究对象,提出基于云模型和证据理论融合的评估算法。采用层次分析法和熵值法相结合的方法确定应急指标权重,运用云模型做为基础对电力系统应急能力进行评估,以解决评价指标模糊性和随机性的问题,并引入D-S证据理论对指标进行综合评估,构建极端天气下电力系统的应急能力评估模型。通过案例证明,该方法可以有效准确地定量和定性评估电力网系统的应急能力,为提高电力网系统的应急管理能力提供科学依据。 展开更多
关键词 云模型 D-s证据理论 层次分析法 熵值法 电力系统应急能力
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