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Design and analysis of a mechanically intelligent system for biomechanical energy harvesting
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作者 Linchuan ZHAO Zewen CHEN +8 位作者 X.CHEN Qiuhua GAO Zhiyuan WU ge yan Kexiang WEI E.M.YEATMAN Guang MENG Wenming ZHANG Hongxiang ZOU 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期235-254,共20页
The rapid advancement of wearable electronic devices has paved the way for a more intelligent and interconnected world.However,ensuring the sustainable energy supply for these devices remains a critical challenge,part... The rapid advancement of wearable electronic devices has paved the way for a more intelligent and interconnected world.However,ensuring the sustainable energy supply for these devices remains a critical challenge,particularly for specialized populations and professionals in demanding environments,where a lack of power can pose life-threatening risks.Herein,we propose a mechanically intelligent biomechanical energy harvesting approach that adapts to complex human motion excitations,thereby improving the energy harvesting performance.Leveraging a mechanical intelligence mechanism,the energy harvester aligns with human physiological habits,selectively activating or deactivating as needed.The system can also adapt to excitations of varying directions,amplitudes,and frequencies.Furthermore,the string tension helps reduce the impact forces on the knee joint during foot strikes.A theoretical model for the biomechanical energy harvesting system is developed to describe its dynamic and electrical characteristics,and a prototype is fabricated and tested under diverse conditions.The experimental results are in good agreement with the simulation trends,validating the effectiveness of the theoretical model.A test subject running at 8 km/h for 90 seconds can successfully power a smartphone for 20 seconds,demonstrating the viability of self-powered applications.This mechanically intelligent biomechanical energy harvesting method holds a promising solution for the sustainable power supply for wearable electronic devices. 展开更多
关键词 energy harvesting biomechanical energy DYNAMICS mechanically intelligent mechanism
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多源不确定环境下物流中心选址与流量分配问题的区间模糊优化
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作者 葛岩 孙岩 李雪飞 《物流科技》 2026年第3期11-15,41,共6页
以物流网络建设运营总成本最低为目标,研究了三级物流网络中物流中心选址与流量分配问题。考虑到物流优化的提前性,为了提高优化的可靠性,从能力、需求、成本出发,系统规划了物流中心选址与流量分配问题面临的多源不确定性。在采用区间... 以物流网络建设运营总成本最低为目标,研究了三级物流网络中物流中心选址与流量分配问题。考虑到物流优化的提前性,为了提高优化的可靠性,从能力、需求、成本出发,系统规划了物流中心选址与流量分配问题面临的多源不确定性。在采用区间模糊数刻画不确定参数的基础上,构建了问题的区间模糊混合整数线性规划模型,进而对模型进行清晰化处理,使得问题优化可解。同时,清晰化模型引入的满意水平能够衡量物流中心选址与流量分配优化方案的可靠性。文章采用算例验证了优化模型的可行性,分析指出物流中心选址与流量分配优化方案的经济性和可靠性是互相矛盾的,提高优化方案的可靠性必然会导致其总成本的提高。算例进一步定义了区间模糊参数的不确定水平,揭示了降低区间模糊参数的不确定水平能够在保证高可靠性的条件下降低物流中心选址与流量分配优化方案的总成本。 展开更多
关键词 物流中心选址 流量分配 多源不确定性 区间模糊数 线性规划模型 不确定水平
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鄂尔多斯盆地东缘致密砂岩储层水基压裂液损害机制贡献度定量评价
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作者 葛岩 刘玉明 +5 位作者 游利军 石雪峰 王艺钧 周龙刚 宣涛 段长江 《石油钻采工艺》 北大核心 2026年第1期86-93,102,共9页
水基压裂液在致密砂岩储层中诱发复杂的复合损害,由于缺乏对损害机制的定量评价方法,导致对损害主控因素认识不清,压裂液优化缺乏精准的科学依据。为量化不同损害机制的贡献,选取了鄂尔多斯盆地东缘物性相近的致密砂岩岩心,以模拟地层... 水基压裂液在致密砂岩储层中诱发复杂的复合损害,由于缺乏对损害机制的定量评价方法,导致对损害主控因素认识不清,压裂液优化缺乏精准的科学依据。为量化不同损害机制的贡献,选取了鄂尔多斯盆地东缘物性相近的致密砂岩岩心,以模拟地层水、蒸馏水、压裂液活性水、压裂液破胶液滤液为实验流体,开展了气驱水相返排平行实验,通过测定气驱前后岩心渗透率变化,实现了对水锁、水敏、化学吸附及微粒运移四类损害机制的定量分离。研究结果表明:在相近物性条件下,实验流体造成的渗透率损害率由大到小依次为:压裂液破胶液滤液、压裂液活性水、模拟地层水和蒸馏水,研究区致密砂岩水基压裂液损害以水锁损害为主(平均贡献度约71%),其次为压裂液吸附损害(平均贡献度约11%),水敏损害和微粒运移损害相对较弱。基于该定量评价结果,提出了针对性的压裂液优化方向,优化后配方使研究区岩心基质渗透率损害率降低至9.12%。该方法可为致密砂岩及其他类似储层压裂液损害的精准评价及压裂液针对性设计提供方法借鉴。 展开更多
关键词 鄂尔多斯盆地东缘 致密砂岩 水基压裂液 损害机制 贡献度评价 压裂液优化
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区间模糊需求下时间敏感型货物多式联运低碳路径优化
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作者 孙岩 葛岩 +1 位作者 王福华 王丹竹 《铁道科学与工程学报》 北大核心 2026年第2期644-654,共11页
为了提高时间敏感型货物多式联运在经济性、环境可持续性、时效性和可靠性上的综合服务水平,增强多式联运对高价值货物的吸引力,本文规划了硬时间窗约束货物送达时间,采用区间模糊数刻画了时间敏感型货物需求的不确定性及其导致的运输... 为了提高时间敏感型货物多式联运在经济性、环境可持续性、时效性和可靠性上的综合服务水平,增强多式联运对高价值货物的吸引力,本文规划了硬时间窗约束货物送达时间,采用区间模糊数刻画了时间敏感型货物需求的不确定性及其导致的运输成本、碳排放量和货物送达时间不确定性。以运输成本最小和运输碳排放量最少为优化目标,研究了时间敏感型货物多式联运低碳路径多目标优化问题。构建了问题优化的多目标模糊线性规划模型,进而采用交互式模糊规划法求得多目标优化问题的帕累托解。通过与碳税政策进行对比,验证了碳税政策在规划时间敏感型货物多式联运低碳路径上的局限性以及多目标优化的可行性。通过情景分析,总结了硬时间窗和多式联运网络能力水平对时间敏感型货物多式联运路径优化的影响,揭示了货主合理设置硬时间窗的重要性以及能力因素对多式联运经营人构建多式联运网络、规划多式联运路径的重要性,同时揭示了降低运输成本、减少碳排放量和提高运输可靠性三者之间的矛盾关系。算例验证结果表明,优化方法具有可行性。算例敏感性分析证明,提高满足水平取值来提高运输可靠性会对时间敏感型货物多式联运路径优化产生显著影响。多式联运经营人可根据货主对3类目标的重视程度选择满足货主需求的满足水平和帕累托解来制定运输方案,组织时间敏感型货物多式联运。 展开更多
关键词 时间敏感型货物 多式联运 路径优化 碳减排 不确定需求 多目标优化 交互式模糊规划
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制度缝隙、效率补偿与适应性效率:新大众文艺生成演化的制度经济学分析
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作者 葛岩 汪文斌 赵汗青 《南京社会科学》 北大核心 2026年第2期124-136,共13页
本文基于新制度经济学视角,运用分析性叙事方法,阐释中国新大众文艺的生成逻辑与演化机制。研究认为,计划体制时期的“效率短缺”导致供给侧与需求侧积累了巨大潜在势能,适逢中国制度变迁时期出现的“制度缝隙”,互联网技术通过提供显... 本文基于新制度经济学视角,运用分析性叙事方法,阐释中国新大众文艺的生成逻辑与演化机制。研究认为,计划体制时期的“效率短缺”导致供给侧与需求侧积累了巨大潜在势能,适逢中国制度变迁时期出现的“制度缝隙”,互联网技术通过提供显著的“效率补偿”,释放了被长期压抑的文化生产力,造就了独步全球的产业规模。在制度变迁过程中,政府采取“适应性效率”策略,容许“双轨制”试错,推动从体制外边缘创新到国家制度吸纳的渐进式融合。然而,平台化生产在大幅降低交易成本的同时,也衍生出不完全契约、算法权力扩张与价值理性缺失等内生张力。这一分析框架揭示了新大众文艺作为技术冲击、市场逻辑与国家治理多重博弈产物的制度意涵,深刻阐释了文化产业变迁的“中国经验”。 展开更多
关键词 新大众文艺 制度经济学 中国经验 效率补偿 适应性效率
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农用拖拉机发动机活塞环组匹配试验研究
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作者 王升升 葛琰 +2 位作者 徐顺利 张重阳 周纪红 《农机化研究》 北大核心 2026年第1期260-267,共8页
在农用拖拉机装配的非道路用发动机的开发试验中,需要对影响其缸内燃烧特性的关键零部件——活塞环组进行针对性匹配研究,以满足功率密度高、热效率高、经济性高、可靠性高和排放水平低等设计特点。为此,以配套农用拖拉机的国四电控高... 在农用拖拉机装配的非道路用发动机的开发试验中,需要对影响其缸内燃烧特性的关键零部件——活塞环组进行针对性匹配研究,以满足功率密度高、热效率高、经济性高、可靠性高和排放水平低等设计特点。为此,以配套农用拖拉机的国四电控高压共轨柴油机为例,选择材料、表面处理、结构不同的3种方案的活塞环组,对比研究摩擦阻力矩、缸内爆发压力、曲轴箱窜气量、外特性燃油消耗率、机械效率和稳态排放等方面的特性,找出该类柴油机应选用的最佳配置型式。试验结果表明:采用球墨铸铁和合金钢材可以降低柴油机的摩擦阻力矩,提高燃油经济性;相比CCC采用CDC表面处理能够增加环组的耐磨性,减少曲轴箱窜气量;气环采用正扭曲梯形桶面环,能够有效增加缸内气体密封性,减少曲轴箱窜气量,但摩擦阻力矩也会相应增大,影响其机械效率;气环增加DLC涂层能进一步降低摩擦阻力矩,但会影响缸内气体的密封性,导致做功能力下降,油耗略微升高;油环的刮油刃高度降低,外圆面PVD处理和磷化处理,可以提高刮油能力,降低摩擦功耗,有效降低PM生成、减少机油消耗率和提高燃油经济性。 展开更多
关键词 农用拖拉机 非道路柴油机 活塞环组 匹配试验
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Decoding the complexity of coding and non-coding RNAs across maize anther development at the isoform level
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作者 ge yan Xuxu Ma +5 位作者 Wei Huang Chunyu Wang Yingjia Han Shufang Wang Han Liu Mei Zhang 《Journal of Genetics and Genomics》 2026年第1期163-176,共14页
Anther is a key male reproductive organ that is essential for the plant life cycle,from the sporophyte to the gametophyte generation.To explore the isoform-level transcriptional landscape of developing anthers in maiz... Anther is a key male reproductive organ that is essential for the plant life cycle,from the sporophyte to the gametophyte generation.To explore the isoform-level transcriptional landscape of developing anthers in maize(Zea mays L.),we analyzed Iso-Seq data from anthers collected at 10 developmental stages,together with strand-specific RNA-seq,CAGE-seq,and PAS-seq data.Of the 152,026 high-confidence full-length isoforms identified,68.8%have not been described;these include 22,365 isoforms that originate from previously unannotated loci and 82,167 novel isoforms that originate from annotated protein-coding genes.Using our newly developed strategy to detect dynamic expression patterns of isoforms,we identify 13,899 differentially variable regions(DVRs);surprisingly,1275 genes contain more than two DVRs,revealing highly efficient utilization of limited genic regions.We identify 7876 long non-coding RNAs(lncRNAs)from 4098 loci,most of which were preferentially expressed during cell differentiation and meiosis.We also detected 371 long-range interactions involving intergenic lncRNAs(lincRNAs);interestingly,243 were lincRNA-gene ones,and the interacting genes were highly expressed in anthers,suggesting that many potential lncRNA regulators of key genes are required for anther development.This study provides valuable resources and fundamental information for studying the essential transcripts of key genes during anther development. 展开更多
关键词 Anther development Long-read transcriptome sequencing ISOFORM Long non-coding RNA MAIZE
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科研类事业单位关键制度改革与成效评估
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作者 徐文勘 葛雁 《中国人事科学》 2026年第2期20-27,共8页
科研类事业单位作为国家创新体系的中坚力量,其体制机制活力直接关系到国家科技竞争力的提升与创新驱动发展战略的落地。长期以来,科研类事业单位在用人、薪酬、财务等方面不同程度地存在行政化色彩浓厚、市场响应迟缓、激励约束不足等... 科研类事业单位作为国家创新体系的中坚力量,其体制机制活力直接关系到国家科技竞争力的提升与创新驱动发展战略的落地。长期以来,科研类事业单位在用人、薪酬、财务等方面不同程度地存在行政化色彩浓厚、市场响应迟缓、激励约束不足等问题,制约了科技创新效能的充分发挥。基于此,文章借鉴新公共管理理论等观点,系统剖析当前科研类事业单位面临的核心制度瓶颈,深入探讨构建以市场化、契约化、弹性化为导向的用人制度,以知识价值、绩效贡献为核心的薪酬制度,以及以授权赋能、结果导向为特征的财务制度的关键路径。在此基础上,进一步提出一套涵盖政治、创新、社会、经济、管理五个维度的改革成效综合评价体系,旨在形成一套既遵循科研规律又契合“企业化管理”精髓的制度闭环与评估范式,为破解改革痛点、提升机构效能、服务国家战略提供理论支撑与实践参考。 展开更多
关键词 科研事业单位 机构改革 人事制度改革 成效评估
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湖湘锦绣非遗的审美特质研究
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作者 葛艳 田香 《西部皮革》 2026年第5期146-148,共3页
文章立足非遗审美研究体系完善与传统工艺当代活化的需求,以湘绣为研究对象从历史脉络、形式表达、审美特征与工艺特性四大维度系统探析,梳理发展轨迹解析形式美学规律,解读文化本义阐释工艺美感,明晰湖湘锦绣独有的艺术特质,即写实与... 文章立足非遗审美研究体系完善与传统工艺当代活化的需求,以湘绣为研究对象从历史脉络、形式表达、审美特征与工艺特性四大维度系统探析,梳理发展轨迹解析形式美学规律,解读文化本义阐释工艺美感,明晰湖湘锦绣独有的艺术特质,即写实与写意交织的形式张力、地域与精神共生的文化深度、精湛与温度交融的工艺质感。研究表明,湖湘锦绣的审美特质是区别于其他传统工艺的核心标识,既为非遗审美研究提供具体参照,也为这一非遗形式的创造性转化与活态传承注入理论支撑。 展开更多
关键词 非物质文化遗产 审美特质 湘绣 文化传承
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利用信息技术实现惠企政策精准服务
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作者 葛燕 庄仲 梁华斌 《信息与电脑》 2026年第5期102-104,共3页
文章针对企业“找不到、看不懂、用不上”惠企政策的难题,通过梳理政策精准服务场景,提出利用移动互联网、大数据等信息技术开发政策精准服务系统,借助手机移动端向企业精准推送政策,建立直接触达企业的服务渠道。此举可帮助企业及时、... 文章针对企业“找不到、看不懂、用不上”惠企政策的难题,通过梳理政策精准服务场景,提出利用移动互联网、大数据等信息技术开发政策精准服务系统,借助手机移动端向企业精准推送政策,建立直接触达企业的服务渠道。此举可帮助企业及时、准确了解最新惠企政策,让企业高效便捷享受政策红利,同时创新政策精准触达企业的模式。 展开更多
关键词 惠企政策 精准服务 信息技术
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Lymphangiogenic and angiogenic microvessel density in human primary sporadic colorectal carcinoma 被引量:6
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作者 ge yan Xiao-yan Zhou +3 位作者 San-Jun Cai Gui-Hong Zhang Jun-Jie Peng Xiang Du 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期101-107,共7页
AIM:To investigate the distribution pattern of lymphatic vessels and microvessels in sporadic colorectal carcinoma(SCRC)and their relationship to metastasis and prognosis.METHODS:The lymphatic vessel density(LVD)and m... AIM:To investigate the distribution pattern of lymphatic vessels and microvessels in sporadic colorectal carcinoma(SCRC)and their relationship to metastasis and prognosis.METHODS:The lymphatic vessel density(LVD)and microvessel density(MVD)in tumor tissue obtained from 132 patients with primary SCRC,including 74 with metastases and 58 without metastases,were evaluated by immunohistochemistry using antibodies directed against D2-40 and yon Willebrand factor(vWF).RESULTS:(1)The lymphatic vessels and microvessels at central portions of SCRC often had a reticular architecture with numerous tiny and ill-defined lumina,while those at tumor borders had large and open lumina.The LVD and MVD were both obviously higher in colorectal cancer patients with metastases than in those without(P〈0.001).(2)For each one lymphatic vessel increased,there was a 1.45-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of LVD in predicting metastasis or non-metastasis in SCRC were 71.62%and 56.90%,respectively,and the corresponding LVD was 5.For each one microvessel increased,there was a 1.11-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of MVD were 66.22%and 51.72%,respectively.(3)Double labeling immunohistochemistry showed D2-40 immunoreactivity to be specific for lymphatic vessels.(4)Univariate analysis indicated that high LVD,high MVD,as well as co-accounting of high LVD and high MVD were associated with patient's poor disease-free survival(Puni〈0.05);multivariate analysis indicated that co-accounting of LVD and MVD was an independent prognostic factor of colorectal cancer,CONCLUSION:D2-40 is a new specific antibody for lymphatic endothelial cells.Lymphogenesis and angiogenesis are commonly seen in SCRC,especially at tumor borders.The detection of LVD and MVD at tumor borders may be useful in predicting metastasis and prognosis in patients with SCRC,and,in particular,coaccounting of LVD and MVD might be a useful prognostic factor in SCRC. 展开更多
关键词 LYMPHANGIOGENESIS ANGIOGENESIS Lymphaticvessel density Microvessel density Sporadic colorectalcarcinoma METASTASIS
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Implementation of Generic AHP Evaluation System and Its Application to Impact Factors of On-Line Consumption Behavior 被引量:2
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作者 ge yan XU Qi LI Hong 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期450-454,共5页
To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study imp... To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evaluation system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evaluation index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invocation of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior. 展开更多
关键词 Web services model expression XML AHP(Analytic Hierarchy Process) online consumption behavior
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基层公共服务供给中的多元主体价值共创机制研究——以P街道“公共服务集市”为例 被引量:4
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作者 赵书松 罗文华 葛燕 《安徽大学学报(哲社版)》 北大核心 2025年第2期132-142,共11页
价值共创是提高公共服务水平的新思路,但“如何实现多元主体价值共创”还有待深入探讨。浙江省P街道的“公共服务集市”按照“发起—运行—结果”的逻辑,逐步采用求同存异、刚柔并济、尽其所长的行为方式,实现政府、民众和其他组织的价... 价值共创是提高公共服务水平的新思路,但“如何实现多元主体价值共创”还有待深入探讨。浙江省P街道的“公共服务集市”按照“发起—运行—结果”的逻辑,逐步采用求同存异、刚柔并济、尽其所长的行为方式,实现政府、民众和其他组织的价值共创目标统一、价值共创关系调适以及价值共创动力激发。公共服务价值共创的前提在于通过任务锚定挖掘资源深度互补性和资源范围互补性;基础在于根据任务资源集构建多元主体交互体系;关键在于地方政府牵头进行资源整合并把控战略方向和组织结构的调节作用。任务、资源和价值的对接耦合为多元主体共同创造基层公共服务领域内物质、精神和关系多种价值提供了新的分析思路。 展开更多
关键词 公共服务供给 多元主体 价值共创 任务资源互补性
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Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation 被引量:1
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作者 Zhiyuan WU Linchuan ZHAO +3 位作者 Han yan ge yan Ao CHEN Wenming ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期111-136,共26页
Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the b... Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery. 展开更多
关键词 shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect
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基于HACCP内控数据的水产品质量安全风险预警
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作者 葛艳 陈睿 +2 位作者 邹一波 陈明 王文娟 《农业机械学报》 北大核心 2025年第6期67-77,共11页
为了加强水产品冷链加工及物流企业对内控数据的隐含质量安全风险管理,实现降本增效,以生食牡蛎HACCP计划为例,从风险指标体系构建入手,构建了质量安全风险预警指标体系,并结合风险预警监控数据的多模态特点,构建了融合群专家领域经验... 为了加强水产品冷链加工及物流企业对内控数据的隐含质量安全风险管理,实现降本增效,以生食牡蛎HACCP计划为例,从风险指标体系构建入手,构建了质量安全风险预警指标体系,并结合风险预警监控数据的多模态特点,构建了融合群专家领域经验知识与深度学习算法的质量安全风险预警模型。在基于HACCP计划设计质量安全预警数据采集点并获得监控数据的基础上,采用AHP方法获得专家的风险指标效用值方案,又采用熵权法优选多专家群决策中的效用值方案,进而确定评级数据,由监控数据以及优选的专家评级数据一起构成原始数据集。为保证预警的敏感度,分别采用了合格数据集和完整数据集作为数据集,融合具有捕捉多维数据中复杂关系能力的LSTM模型与具有处理复杂分类边界能力的RBF模型构建预警模型开展仿真实验,并做LSTM模型、RBF模型以及融合的LSTM-RBF模型在不同数据集上的对比分析。实验结果表明,融合的LSTM-RBF模型在合格数据集和完整数据集上都有96%和90%的准确率,而且合格数据集上的测试效果明显更好。 展开更多
关键词 HACCP 内控数据 深度学习 群决策 预警
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Pharmacokinetics of gene recombined angiogenesis inhibitor Kringle 5 in vivo using 131I specific markers and SPECT/CT
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作者 ge yan Danrong yang +6 位作者 yan Yu Jianjun Xue Yifan Jia Xuanzi Sun Boyu Wang Zewei Zhao Maode Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第5期313-317,共5页
The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokin... The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokinetics, the determination of metabolic principles, and evaluation of treatment effect. The objective of the study was to investigate the pharmacokinetic characteristics of gene recombination angiogenesis inhibitor Kringle 5 in vivo. The SPECT/CT and specific^(131)I-Kringle 5 marked by Iodogen method were both applied to explore the pharmacokinetic characteristics of^(131)I-Kringle 5 in vivo, and to investigate the dynamic distributions of^(131)I-Kringle 5 in target organs. Labeling recombinant angiogenesis inhibitor Kringle 5 using131 I with longer half-life and imaging in vivo using SPECT instead of PET,could overcome the limitations of previous methods. When the doses of^(131)I-Kringle 5 were 10.0, 7.5 and5.0 g/kg, respectively, the two-compartment open models can be determined within all the metabolic process in vivo. There were no significant differences in t1/2α, t1/2β, apparent volume of distribution and CL between those three levels. The ratio of AUC(0 1)among three different groups of 10.0, 7.5 and 5.0 g/kg was 2.56:1.44:1.0, which was close to the ratio(2:1.5:1.0). It could be clear that in the range of 5.0–10.0 g/kg, Kringle 5 was characterized by the first-order pharmacokinetics. Approximately 30 min after^(131)I-Kringle 5 was injected,^(131)I-Kringle 5 could be observed to concentrate in the heart, kidneys, liver and other organs by means of planar imaging and tomography. After 1 h of being injected, more radionuclide retained in the bladder, but not in intestinal. It could be concluded that^(131)I-Kringle 5 is mainly excreted through the kidneys. About 2 h after the injection of^(131)I-Kringle 5, the radionuclide in the heart, kidneys,liver and other organs was gradually reduced, while more radionuclide was concentrated in the bladder.The radionuclide was completely metabolized within 24 h, and the distribution of radioactivity in rats was similar to normal levels. In our study, the specific marker^(131)I-Kringle 5 and SPECT/CT were successfully used to explore pharmacokinetic characteristics of Kringle 5 in rats. The study could provide a new evaluation platform of the specific, in vivo and real-time functional imaging and pharmacokinetics for the clinical application of^(131)I-Kringle 5. 展开更多
关键词 131 I ISOTOPE labeling Vascular inhibitor KRINGLE 5 SPECT/CT imaging technology RECOMBINANT drugs PHARMACOKINETICS in vivo
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Recognition of Fluvial Bank Erosion Along the Main Stream of the Yangtze River
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作者 ge yan Heqin Cheng +6 位作者 Zeyu Jiang Lizhi Teng Ming Tang Tian Shi Yuehua Jiang Guoqiang yang Quanping Zhou 《Engineering》 SCIE EI CAS 2022年第12期50-61,共12页
Recognizing the risk of fluvial bank erosion is an important challenge to ensure the early warning and prevention or control of bank collapse in river catchments,including in the Yangtze River.This study introduces a ... Recognizing the risk of fluvial bank erosion is an important challenge to ensure the early warning and prevention or control of bank collapse in river catchments,including in the Yangtze River.This study introduces a geomorphons-based algorithm to extract river bank erosion information by adjusting the flatness from multibeam echo-sounding data.The algorithm maps ten subaqueous morphological elements,including the slope,footslope,flat,ridge,peak,valley,pit,spur,hollow,and shoulder.Twentyone flatness values were used to build an interpretation strategy for the subaqueous features of riverbank erosion.The results show that the bank scarp,which is the erosion carrier,is covered by slope cells when the flatness is 10°.The scour pits and bank scars are indicated by pit cells near the bank and hollow cells in the bank slope at a flatness of 0°.Fluvial subaqueous dunes are considered an important factor accelerating bank erosion,particularly those near the bank toe;the critical flatness of the dunes was evaluated as 3°.The distribution of subaqueous morphological elements was analyzed and used to map the bank erosion inventory.The analysis results revealed that the near-bank zone,with a relatively large water depth,is prone to form large scour pits and a long bank scarp.Arc collapse tends to occur at the long bank scarp to shorten its length.The varied assignment of flatness values among terrestrial,marine,and fluvial environments is discussed,concluding that diversified flatness values significantly enable fluvial subaqueous morphology recognition.Consequently,this study provides a reference for the flatness-based recognition of fluvial morphological elements and enhances the targeting of subaqueous signs and risks of bank failure with a range of multibeam bathymetric data. 展开更多
关键词 Multibeam echo-sounding data Morphological elements Bank erosion Bank scarp Scour pits Bank collapse
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Teaching Second Language Vocabulary:the Role and Application of the AWL
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作者 ge yan 《Review of Educational Theory》 2020年第3期52-56,共5页
This paper focuses on the role and application of AWL in science-related subjects,namely the issue of whether or not students in science-related majors is advantaged or disadvantaged in using the Academic Word List(AW... This paper focuses on the role and application of AWL in science-related subjects,namely the issue of whether or not students in science-related majors is advantaged or disadvantaged in using the Academic Word List(AWL)in their academic writing assignments as the imbalance of word frequency in AWL.Participants(n=18)are obliged to answer the Questionnaire.Furthermore,if needed,a brief interview would be arranged on some uncertain questions.Results show that learning and acquiring academic vocabulary would benefit participants in research articles,while AWL is inadequate for students in science-related disciplines in their academic writing.We claim that students in science-related majors may be disadvantaged than other majors’students in using Coxhead’s Academic Word List,and a wordlist screened out from science-related corpus perhaps more suitable for ESP students.Meanwhile,AWL,as a role of reference,would aid language learning or acquisition. 展开更多
关键词 AWL Academic vocabulary Academic writing ESP
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融合无人机多时相参数的冬小麦单产估测方法 被引量:4
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作者 葛焱 朱志畅 +4 位作者 臧晶荣 张睿男 金时超 徐焕良 翟肇裕 《农业机械学报》 北大核心 2025年第1期344-355,共12页
为探讨无人机遥感与多时相参数融合在冬小麦单产预测中的潜力,采集了冬小麦7个生育期的无人机RGB和多光谱数据,从中分别提取光谱参数和形态参数,采用5种机器学习算法建模,比较不同生育期单产预测效果,在此基础上,筛选优势参数组合,分别... 为探讨无人机遥感与多时相参数融合在冬小麦单产预测中的潜力,采集了冬小麦7个生育期的无人机RGB和多光谱数据,从中分别提取光谱参数和形态参数,采用5种机器学习算法建模,比较不同生育期单产预测效果,在此基础上,筛选优势参数组合,分别比较不同生育期及参数组合与单产预测之间的相关性。结果表明,不同生育期及参数组合对冬小麦单产预测具有不同影响;单生育期时,灌浆期和开花期预测效果最佳,其次为抽穗期、孕穗期、成熟期、拔节期和分蘖期;多生育期时,双生育期、三生育期、四生育期组合预测精度逐渐升高,但考虑到增长幅度以及数据采集、算力开销、处理成本等因素,“拔节期+抽穗期+灌浆期”的三生育期组合经济性最高。5种机器学习算法整体预测精度从高到低分别为反向传播神经网络、随机森林、支持向量机、极端梯度提升和逐步多元回归,通过机器学习可解释性方法SHAP优选的光谱和形态参数组合虽然不同生育期有所不同,但除拔节期外,均能提高单产预测精度。研究结果可为冬小麦单产预测提供方法依据和技术参考。 展开更多
关键词 冬小麦 单产预测 无人机遥感 机器学习 多时相参数 SHAP法
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Geochemistry and the genesis of natural gases in the deep reservoirs of the Bozhong Depression,Bohai Bay Basin,China
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作者 Feilong Wang Guomin Tang +2 位作者 Zilong Zhao Rongtao Chen ge yan 《Natural Gas Industry B》 2024年第6期645-660,共16页
A large gas field with reserves of nearly 200 billion m^(3)dBZ19-6dwas discovered in the Bozhong Depression in the Bohai Bay Basin in 2018.There is a considerable difference between the amount of natural gas that woul... A large gas field with reserves of nearly 200 billion m^(3)dBZ19-6dwas discovered in the Bozhong Depression in the Bohai Bay Basin in 2018.There is a considerable difference between the amount of natural gas that would traditionally be expected to be generated by the thermal degradation of low-mature kerogens and the resources that have been confirmed by exploration.Therefore,the geochemical characteristics and the genesis of gas have become crucial aspects of investigating deep natural gas in the Bozhong Depression.The deep gas in the depression is predominantly methane.Its dry coefficient(C_(1)/C_(1-5))ranges from 0.73 to 0.94,which is generally characterized as wet gas.The main nonhydrocarbon gases are CO_(2)(1.26%-52.00%)and N_(2)(0.1%-0.74%),with traces of H_(2)S(10.44×10^(-6)-36.63×10^(-6) ppm).The natural gases are thermogenic oil-type gases from the Shahejie and Dongying Formations.The deep natural gas in the Bozhong Depression is mainly derived from kerogen degradation,with contributions from oil cracking gas in the BZ1/19 and BZ2/3 structures.Complex carbon isotopic reversals are caused by the filling and mixing of natural gas with different maturities from the same source,evaporative fractionation due to the filling of late-stage high-mature natural gas,and Rayleigh fractionation under deep exogenous temperatures in the presence of transition metals.Combining the analysis of the fluid properties of natural gas,the evaluation of the performance of the migration system,and the understanding of the accumulation background indicates a high possibility that the gas was supplied from multiple hydrocarbon sources over long distances in the late stage.Thus,advantageous traps with high temperatures,close proximity to source kitchens,and favorable migration conditions are the preferred targets for future natural gas exploration in the Bozhong Depression. 展开更多
关键词 BZ19-6 gas field Deep reservoirs GEOCHEMISTRY GENESIS Rayleigh fractionation
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