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萧山区恶性肿瘤死亡趋势分析

预防医学 2024年第1期36卷 78-81,85页

作者：赵芳芳林君英王冬飞李玉荣高媛媛蒋园园杭州市萧山区疾病预防控制中心慢性病防制科浙江杭州311203

目的了解2017—2022年杭州市萧山区恶性肿瘤死亡趋势,为开展恶性肿瘤防控工作提供依据。方法通过杭州市慢性病监测管理系统收集2017—2022年萧山区居民恶性肿瘤死亡病例资料,分析死因构成比和粗死亡率,采用2010年第六次全国人口普查数... 详细信息

目的了解2017—2022年杭州市萧山区恶性肿瘤死亡趋势,为开展恶性肿瘤防控工作提供依据。方法通过杭州市慢性病监测管理系统收集2017—2022年萧山区居民恶性肿瘤死亡病例资料,分析死因构成比和粗死亡率,采用2010年第六次全国人口普查数据计算标化死亡率;采用平均年度变化百分比(AAPC)分析恶性肿瘤死亡趋势。结果2017—2022年萧山区恶性肿瘤死亡13301例,占全死因构成的31.26%,居死因首位;年均粗死亡率为186.36/10万,标化死亡率为106.63/10万。2017—2022年粗死亡率无明显变化趋势(P>0.05),标化死亡率呈下降趋势(AAPC=-1.409%,P0.05),标化死亡率呈下降趋势(AAPC=-3.017%,P0.05)。45~<65岁和≥65岁居民恶性肿瘤粗死亡率呈下降趋势(AAPC=-3.933%和-2.413%,均P<0.05),0~<15岁、45~<65岁和≥65岁组男性粗死亡率高于女性(均P<0.05)。恶性肿瘤前五位死因依次为肺癌、结直肠癌、肝癌、胃癌和胰腺癌,占全部恶性肿瘤的66.96%;结直肠癌粗死亡率呈上升趋势(AAPC=2.815%,P<0.05)。结论2017—2022年萧山区恶性肿瘤标化死亡率呈下降趋势,≥45岁男性是恶性肿瘤防控重点人群;导致死亡的主要恶性肿瘤为肺癌、结直肠癌、肝癌、胃癌和胰腺癌。

关键词：恶性肿瘤死亡率平均年度变化百分比

2015—2021年萧山区4类慢性病死亡及早死概率分析

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预防医学 2024年第2期36卷 147-151页

作者：蒋园园王冬飞林君英李玉荣高媛媛赵芳芳徐红杭州市萧山区疾病预防控制中心慢性病防制科浙江杭州311201 杭州市萧山区疾病预防控制中心浙江杭州311201

目的了解2015—2021年杭州市萧山区恶性肿瘤、糖尿病、心脑血管疾病和慢性呼吸系统疾病的死亡率、早死概率及其变化趋势,为制定慢性病防控策略提供依据。方法通过浙江省慢性病监测管理系统收集2015—2021年萧山区4类慢性病死亡资料,... 详细信息

目的了解2015—2021年杭州市萧山区恶性肿瘤、糖尿病、心脑血管疾病和慢性呼吸系统疾病的死亡率、早死概率及其变化趋势,为制定慢性病防控策略提供依据。方法通过浙江省慢性病监测管理系统收集2015—2021年萧山区4类慢性病死亡资料,计算粗死亡率、标化死亡率和早死概率;采用年均变化百分比(AAPC)分析死亡率和早死概率的变化趋势;采用2025年和2030年早死概率控制目标评价4类慢性病早死概率达标情况。结果 2015—2021年萧山区4类慢性病死亡36 130例,粗死亡率为445.20/10万,标化死亡率为237.81/10万,均呈下降趋势(AAPC=-1.427%和-4.051%,均P0.05)。恶性肿瘤早死概率呈下降趋势(AAPC=-4.167%,P0.05)。4类慢性病早死概率平均每年下降4.00%,预测2025年和2030年早死概率可下降至6.64%和5.42%,均低于目标值7.99%和6.99%。结论 2015—2021年萧山区居民4类慢性病死亡率和早死概率呈下降趋势,其中恶性肿瘤早死概率下降较明显,预测2025年和2030年4类慢性病早死概率均能达到目标值。

关键词：慢性病早死概率死亡率趋势

Fabrication and manipulation of nanosized graphene homojunction with atomically-controlled boundaries

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Nano Research 2020年第12期13卷 3286-3291页

作者： Hui Chen De-Liang Bao dongfei wang Yande Que Wende Xiao Yu-Yang Zhang Jiatao Sun Shixuan Du Hong-Jun Gao Institute of Physics and University of Chinese Academy of Sciences Beijing100190China CAS Key Laboratory of Vacuum Physics University of Chinese Academy of SciencesBeijing100049China

Controlling the atomic configurations of structural defects in graphene nanostructures is crucial for achieving desired ***,we report the controlled fabrication of high-quality single-crystal and bicrystal graphene nanoislands(GNI)through a unique top-down etching and post-annealing procedure on a graphite ***-temperature scanning tunneling microscopy(STM)combined with density functional theory calculations reveal that most of grain boundaries(GBs)formed on the bicrystal GNIs are 5-7-5-7 *** nanodomains separated by a 5-7-5-7 GB are AB stacking and twisted stacking with respect to the underlying graphite substrate and exhibit distinct electronic properties,forming a graphene *** addition,we construct homojunctions with alternative AB/twisted stacking nanodomains separated by parallel 5-7-5-7 ***,the stacking orders of homojunctions are manipulated from AB/twist into twist/twist type through a STM *** controllable fabrication and manipulation of graphene homojunctions with 5-7-5-7 GBs and distinct stacking orders open an avenue for the construction of GBs-based devices in valleytronics and twistronics.

关键词： homojunction graphene nanoislands manipulations grain boundaries twisted stacking

Construction of bilayer PdSe2 on epitaxial graphene

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Nano Research 2018年第11期11卷 5858-5865页

作者： En Li dongfei wang Peng Fan Ruizi Zhang Yu-Yang Zhang Geng Li Jinhai Mao Yeliang wang Xiao Lin Shixuan Du Hong-Jun Gao Institute of Physics & University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing 1 O0190 Chino

Two-dimensional (2D) materials have received significant attention due to their unique physical properties and potential applications in electronics and optoelectronics. Recent studies have demonstrated that exfoliated PdSe2, a layered transition metal dichalcogenide (TMD), exhibits ambipolar field-effect transistor (FET) behavior with notable performance and good air stability, and thus serves as an emerging candidate for 2D electronics. Here, we report the growth of bilayer PdSe2 on a graphene-SiC(0001) substrate by molecular beam epitaxy (MBE). A bandgap of 1.15 ± 0.07 eV was revealed by scanning tunneling spectroscopy (STS). Moreover, a bandgap shift of 0.2 eV was observed in PdSe2 layers grown on monolayer graphene as compared to those grown on bilayer graphene. The realization of nanoscale electronic junctions with atomically sharp boundaries in 2D PdSe2 implies the possibility of tuning its electronic or optoelectronic properties. In addition, on top of the PdSe2 bilayers, PdSe2 nanoribbons and stacks of nanoribbons with a fixed orientation have been fabricated. The bottom-up fabrication of low-dimensional PdSe2 structures is expected to enable substantial exploration of its potential applications.

关键词： two-dimensional materials transition-metal dichalcogenides PdSe 2 scanning tunneling microscopy/spectroscopy semiconducting bandgap nanoribbon

Recovery of edge states of graphene nanoislands on an iridium substrate by silicon intercalation

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Nano Research 2018年第7期11卷 3722-3729页

作者： Hui Chen Yande Que Lei Tao Yu-Yang Zhang Xiao Lin Wende Xiao dongfei wang Shixuan Du Sokrates T. Pantelides Hong-Jun Gao Institute of Physics & University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing 100190 China Department of Physics and Astronomy Vanderbilt University Nashville Tennessee 37235 USA Department of Electrical Engineering and Computer Science Vanderbilt University Nashville Tennessee 3723S USA

Finite-sized graphene sheets, such as graphene nanoislands （GNIs）, are promising candidates for practical applications in graphene-based nanoelectronics. GNIs with well-defined zigzag edges are predicted to have spin-polarized edge-states similar to those of zigzag-edged graphene nanoribbons, which can achieve graphene spintronics. However, it has been reported that GNIs on metal substrates have no edge states because of interactions with the substrate. We used a combination of scanning tunneling microscopy, spectroscopy, and density functional theory calculations to demonstrate that the edge states of GNIs on an Ir substrate can be recovered by intercalating a layer of Si atoms between the GNIs and the substrate. We also found that the edge states gradually shift to the Fermi level with increasing island size. This work provides a method to investigate spin-polarized edge states in high-quality graphene nanostructures on a metal substrate.

关键词： graphene nanoisland zigzag edge edge state scanning tunneling microscopy density functional theory

Bandgap broadening at grain boundaries in single-layer MoS2

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Nano Research 2018年第11期11卷 6102-6109页

作者： dongfei wang Hua Yu Lei Tao Wende Xiao Peng Fan Tingting Zhang Mengzhou Liao Wei Guo Dongxia Shi Shixuan Du Guangyu Zhang Hongjun Gao Institute of Physics & University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing I00190 China School of Physics Beijing Institute of Technology Beijing 10008 I China

Two-dimensional semiconducting transition-metal dichalcogenides have attracted considerable interest owing to their unique physical properties and future device applications. In particular, grain boundaries (GBs) have been often observed in single-layer MoS2 grown via chemical vapor deposition, which can significantly influence the material properties. In this study, we examined the electronic structures of various GBs in single-layer MoS2 grown on highly oriented pyrolytic graphite using low-temperature scanning tunneling microscopy/spectroscopy. By measuring the local density of states of a series of GBs with tilt angles ranging from 0° to 25°, we found that the bandgaps at the GBs can be either broadened or narrowed with respect to the intrinsic single-layer MoS2. The bandgap broadening shows that the GBs can become more insulating, which may directly influence the transport properties of nanodevices based on polycrystalline single-layer MoS2 and be useful for optoelectronics.

关键词： MoS 2 grain boundary bandgap scanning tunneling microscopy

基于改进支持向量回归的旋片泵自相关过程监控

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工业工程与管理 2022年第6期27卷 9-13页

作者：郑辉姜美玲王东菲天津科技大学工业工程系天津300222

为了更好地实现对旋片泵自相关过程有效监控,基于混沌遗传算法(chaotic genetic algorithm,CGA),提出优化传统支持向量回归机(support vector regression,SVR)的方法,简称为CGASVR。并运用CGA-SVR对单级旋片泵的噪音和温度两个质量特性... 详细信息

为了更好地实现对旋片泵自相关过程有效监控,基于混沌遗传算法(chaotic genetic algorithm,CGA),提出优化传统支持向量回归机(support vector regression,SVR)的方法,简称为CGASVR。并运用CGA-SVR对单级旋片泵的噪音和温度两个质量特性自相关统计过程进行监控,实践证明该方法不仅可以有效滤除自相关,而且能克服SVR模型的超参数过早陷入局部最优这一缺陷。进而基于CGA-SVR模型构建的多变量残差MEWMA控制图,在旋片泵自相关监控过程中有更好体现。

关键词：遗传算法支持向量回归机旋片泵自相关 MEWMA控制图

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MT5500B卡车辅助动力源失效行为分析

露天采矿技术 2023年第3期38卷 122-124页

作者：王东飞国能准能集团有限责任公司哈尔乌素露天煤矿内蒙古鄂尔多斯010300

为了解决MT5500B卡车辅助动力源失效故障,基于故障现象找出了导致故障发生的原因,并提出了相关故障解决方案。结果表明:故障解决方案的有效实施,使卡车辅助动力源故障得到解除;卡车平辅助动力源故障的有效控制,使卡车运行与人员作业安... 详细信息

为了解决MT5500B卡车辅助动力源失效故障,基于故障现象找出了导致故障发生的原因,并提出了相关故障解决方案。结果表明:故障解决方案的有效实施,使卡车辅助动力源故障得到解除;卡车平辅助动力源故障的有效控制,使卡车运行与人员作业安全性有了更高的保障。

关键词： MT5500卡车动力源故障率举升泵转向泵液压系统

基于安全风险预测的自动驾驶自适应巡航控制优化

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同济大学学报（自然科学版） 2024年第4期52卷 512-519页

作者：汪敏涂辉招薛东飞李浩李千山同济大学道路与交通工程教育部重点实验室上海201804 宝马中国研发中心上海200232

从周边车辆运动学状态参数和道路设施条件参数中提取场景特征指标和安全风险度量指标,采用极端梯度提升模型(XGboost)和长短时记忆模型(LSTM)进行安全风险预测,由此提出基于安全风险预测的自动驾驶自适应巡航控制(ACC)优化方法,并选取... 详细信息

从周边车辆运动学状态参数和道路设施条件参数中提取场景特征指标和安全风险度量指标,采用极端梯度提升模型(XGboost)和长短时记忆模型(LSTM)进行安全风险预测,由此提出基于安全风险预测的自动驾驶自适应巡航控制(ACC)优化方法,并选取碰撞发生概率、速度平均值、速度标准差3种指标评价ACC表现。通过Prescan和Simulink联合仿真推演,验证了ACC优化方法的合理性和有效性。结果表明,基于安全风险预测的ACC优化方法的控制表现优于一般ACC;利用LSTM预测安全风险,相比XGboost具有更好的ACC优化表现;预测安全风险时增加道路设施条件参数,显著提升了ACC表现,降低了自动驾驶碰撞发生概率。

关键词：交通运输自动驾驶安全风险预测控制优化仿真推演