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Science Bulletin 2019年第6期64卷 370-373页

作者： Peng Gong Han Liu Meinan Zhang Congcong Li Jie Wang Huabing Huang Nicholas Clinton Luyan Ji Wenyu Li Yuqi Bai Bin Chen Bing xu Zhiliang Zhu Cui Yuan Hoi Ping Suen Jing Guo Nan xu Weijia Li Yuanyuan Zhao Jun Yang Chaoqing Yu Xi Wang Haohuan fu Le Yu Iryna Dronova Fengming Hui Xiao Cheng xueli Shi Fengjin Xiao Qiufeng Liu Lianchun Song Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System Science Tsinghua University AI for Earth Lab Cross-Strait Institute Tsinghua University Department of Environmental Science Policy and Management University of CaliforniaBerkeley State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Google LLC Institute of Electronics Chinese Academy of Sciences United States Geological Survey National Supercomputing Center in Wuxi Department of Landscape Architecture University of CaliforniaBerkeley State Key Laboratory of Remote Sensing Science College of Global Change and Earth System Science Beijing Normal University National Climate Center China Meteorological Administration

As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.

关键词： the world strives to reduce timely and higher resolution information is urgently needed

一种测量二极管侧面抽运固体激光器热焦距的方法

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物理学报 2008年第11期57卷 6987-6991页

作者：耿爱丛赵慈薄勇鲁远甫许祖彦北京工商大学数理系北京100037 中国科学院物理研究所北京凝聚态物理国家实验室北京100190

提出了一种能够简单、准确测量二极管侧面抽运固体激光器热透镜焦距的方法,明确提出采用非对称平平腔测量时,激光晶体端面与腔镜的间距不需要为零,并从实验上证明了方法的可靠性.应用该方法的测量结果可以优化复合折叠和频黄光激光器的... 详细信息

提出了一种能够简单、准确测量二极管侧面抽运固体激光器热透镜焦距的方法,明确提出采用非对称平平腔测量时,激光晶体端面与腔镜的间距不需要为零,并从实验上证明了方法的可靠性.应用该方法的测量结果可以优化复合折叠和频黄光激光器的结构,保证两束基频在腔内达到最佳的空间重合,提高腔内和频效率.

关键词：全固态激光器 Nd∶YAG激光器热焦距腔内和频

粤北南雄盆地县域土地利用变化与生境质量演变

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中国城市林业 2024年第4期22卷 139-146页

作者：邓光蔓杨现坤徐国良符加方莫凌梓杨漫凌雨楠李俐宽李委庭蔡志云广州大学地理科学与遥感学院广州510006 广东省农村水环境面源污染综合治理工程技术研究中心广州510006 南雄市自然资源局广东韶关512400

南雄位于广东省“一核一带一区”发展格局中的北部生态发展区,是广东省重要生态屏障的组成部分,但由于早期不合理的农耕发展生成了大量的未利用地,对生境质量造成负面影响。基于2000、2005、2010、2015和2020年的土地利用数据,运用InVES... 详细信息

南雄位于广东省“一核一带一区”发展格局中的北部生态发展区,是广东省重要生态屏障的组成部分,但由于早期不合理的农耕发展生成了大量的未利用地,对生境质量造成负面影响。基于2000、2005、2010、2015和2020年的土地利用数据,运用InVEST模型,对4个周期(2000—2005年、2005—2010年、2010—2015年、2015—2020年)的生境质量演变特征进行评价,并利用生境质量贡献率探究影响生境质量变化的土地利用转移类型。结果表明:1)2000—2020年南雄市土地利用变化以耕地与林地之间的相互转化以及耕地转化为建设用地为主;2)南雄市生境质量呈现先上升后下降的趋势,中部丘陵生境质量低,西北部以及东南部高山是高生境质量的分布区;3)2000—2020年,耕地向林地转化是研究区生境质量提升的最主要原因,林地向耕地转化以及耕地向建设用地转化是研究区生境质量下降的主要原因。因此,协调林地与耕地、耕地与建设用地之间的转化将会有效缓解南雄市生境质量下降问题。

关键词：土地利用变化 InVEST模型生境质量南雄市

改进YOLOv5的轻量化RGB-IR融合小目标检测

同方期刊数据库博看期刊评论

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办公自动化 2024年第17期29卷 65-68页

作者：郭月飞阳旭葛晨阳武汉天喻信息产业股份有限公司西安分公司西安710076 西安交通大学人工智能学院西安710049

针对RGB-IR图像中的目标检测问题,文章提出一种基于YOLOv5的轻量化RGB-IR融合小目标检测算法。该算法首先使用单应性变换对齐RGB与IR图像,并拼接为四通道张量输入检测网络,以实现联合特征提取。其次,使用SE注意力机制分配特征通道权重,... 详细信息

针对RGB-IR图像中的目标检测问题,文章提出一种基于YOLOv5的轻量化RGB-IR融合小目标检测算法。该算法首先使用单应性变换对齐RGB与IR图像,并拼接为四通道张量输入检测网络,以实现联合特征提取。其次,使用SE注意力机制分配特征通道权重,以实现特征级融合,减少特征矛盾并提高检测的鲁棒性,并进一步改进网络连接,使用浅层特征以增强小目标检测准确性。最后,使用Ghost卷积替代传统卷积,以降低计算量与参数量。实验结果表明,该融合检测算法在小目标数据集上验证改进结果明显,并实现嵌入式部署验证,在2TOPS算力NPU上实现30fps帧率的实时检测。

关键词： RGB-IR融合目标检测小目标检测 YOLOv5 模型轻量化注意力机制

Shear-induced Stabilization of the Nematic Phasein a Side Group-containingPoly(aryl ether ketone) Copolymer

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Chemical Research in Chinese Universities 2001年第2期17卷 233-236页

作者： SUN Hui, MA Jia, BEN Teng, WANG Han-fu CHEN Chun-hai, ZHANG Wan-jin, JIANG Zhen-hua and WU Zhong-wen (Department of Chemistry, Jilin University, Changchun 130023, P. R. China) xu Ying-kai (Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 吉林大学吉林长春 130023 中科院化学所北京 100080 浙江大学浙江杭州 310027

Shear induced stabilization of the nematic phase in a side group-containing poly(aryl ether ketone) copolymer was studied. The temperature dependence of viscosity at different shear rates was displayed. Polymers in the nematic state showed lower melt viscosities than isotropic polymers with similar structures. Experimental results indicated that the temperature at which the viscosity maximum appeared shifted to higher ones with increasing levels of shear rate. This was found to induce mesophase stabilization of the thermotropic polymer.

关键词： Thermotropic liquid crystalline polymer Poly (aryl ether ketone) Shear flow Molecular orientation

用于位移传感器的全息平面变间距光栅设计与制作研究

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物理学报 2006年第12期55卷 6405-6409页

作者：楼俊付绍军徐向东何世平中国科学技术大学国家同步辐射实验室中国科学技术大学力学和机械工程系合肥230029

简述了全息变间距光栅的几何理论.利用遗传算法对记录光路进行了优化计算,提出在目标函数中考虑记录参数误差的影响,推导了目标函数的积分形式,提高了计算效率.针对用于位移传感器的平面变间距光栅,分别计算了球面波干涉及球面波与非球... 详细信息

简述了全息变间距光栅的几何理论.利用遗传算法对记录光路进行了优化计算,提出在目标函数中考虑记录参数误差的影响,推导了目标函数的积分形式,提高了计算效率.针对用于位移传感器的平面变间距光栅,分别计算了球面波干涉及球面波与非球面波干涉情况下的全息记录参数,给出了线密度误差曲线.制作出全息平面变间距光栅,并成功应用于位移传感器中.

关键词：全息光栅变间距光栅遗传算法

Intermittent Oxygen Inhalation with Proper Frequency Improves Overall Health Conditions and Alleviates Symptoms in a Population at High Risk of Chronic Mountain Sickness with Severe Symptoms

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Chinese Medical Journal 2016年第11期129卷 1322-1329页

作者： Bin Feng Wei-Hao xu Yu-Qi Gao fu-Yu Liu Peng Li Shan-Jun Zheng Lu-Yue Gai Gang Zhang Department of Cardiology Chinese People's Liberation Army General Hospital Beijing 100853 China Department of High Altitucle Military Hygiene College of High Altitude Military Medicine Third MilitarY Meclical University Chongqing 400030 China Institute of Medicine and Hygienic Equipment for High Altitude Region College of High Altitude Military Medicine Third Military Medical University Chongqing 400030 China

Background： Oxygen inhalation therapy is essential for the treatment of patients with chronic mountain sickness （CMS）, but the efficacy of oxygen inhalation for populations at high risk of CMS remains unknown. This research investigated whether oxygen inhalation therapy benefits populations at high risk of CMS. Methods： A total of 296 local residents living at an altitude of 3658 m were included; of which these were 25 diagnosed cases of CMS, 8 cases dropped out of the study, and 263 cases were included in the analysis. The subjects were divided into high-risk （180 ≤ hemoglobin （Hb）〈210 g/L, n = 161） and low-risk （Hb 〈180 g/L, n = 102） groups, and the cases in each group were divided into severe symptom （CMS score ≥6） and mild symptom （CMS score 0-5） subgroups. Severe symptomatic population of either high- or low-risk CMS was randomly assigned to no oxygen intake group （A group） or oxygen intake 7 times/week group （D group）; mild symptomatic population of either high- or low-risk CMS was randomly assigned to no oxygen intake group （A group）, oxygen intake 2 times/week group （B group）, and 4 times/week group （C group）. The courses for oxygen intake were all 30 days. The CMS symptoms, sleep quality, physiological biomarkers, biochemical markers, etc., were recorded on the day before oxygen intake, on the 15th and 30th days of oxygen intake, and on the 15th day after terminating oxygen intake therapy. Results： A total of 263 residents were finally included in the analysis. Among these high-altitude residents, CMS symptom scores decreased for oxygen inhalation methods B, C, and D at 15 and 30 days after oxygen intake and 15 days after termination, including dyspnea, palpitation, and headache index, compared to those before oxygen intake （B group： Z = 5.604, 5.092, 5.741; C group： Z = 4.155, 4.068, 4.809; D group： Z = 6.021, 6.196, 5.331, at the 3 time points respectively; all P 〈 0.05/3 vs. before intake）. However, dyspnea/palpitation （A group： Z = 5.003, 5.428, 5.493,

关键词： Chronic Mountain Sickness Efficacy Hypoxia Individualized Therapy Oxygen Inhalation

Influence of granulocyte colony-stimulating factor on cardiac function in patients with acute myocardial infarction and leukopenia after revascularization

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Chinese Medical Journal 2010年第14期123卷 1827-1832页

作者： GUO Shi-zun WANG Ning-fu ZHOU Liang YE Xian-hua PAN Hao TONG Guo-xin YANG Jian-min xu Jian Department of Cardiology First Municipal Hospital of Hangzhou & Affiliated Hangzhou Hospital of Nanjing Medical University Hangzhou Zhejiang 310006 China

Background Granulocyte colony-stimulating factor （G-CSF） seems to improve cardiac function and perfusion when used systemically through mobilization of stem cells into peripheral blood, but results of previous clinical trials remain controversial. This study was designed to investigate safety and efficacy of subcutaneous injection of G-CSF on left ventricular function in patients with impaired left ventricular function after ST-segment elevation myocardial infarction （STEMI）. Methods Thirty-three patients （22 men; age, （68.5±6.1） years） with STEMI and with comorbidity of leukopenia were included after successful primary percutaneous coronary intervention within 12 hours after symptom onset. Patients were randomized into G-CSF group who received G-CSF （10 μg/kg of body weight, daily） for continuous 7 days and control group. Results of blood analyses, echocardiography and angiography were documented as well as possibly occurred adverse events. Results No severe adverse events occurred in both groups. Mean segmental wall thickening in infract segments increased significantly at 6-month follow up compared with baseline in both groups, but the longitudinal variation between two groups had no significant difference （P〉0.05）. The same change could also be found in longitudinal variation of wall motion score index of infarct segments （P 〉0.05）. At 6-month follow-up, left ventricular end-diastolic volume of both groups increased to a greater extent, but there were no significant differences between the two groups when comparing the longitudinal variations （P 〉0.05）. In both groups, left ventricular ejection fraction measured by echocardiography ameliorated significantly at 6-month follow-up （P 〈0.05）, but difference of the longitudinal variation between two groups was not significant （P 〉0.05）. When pay attention to left ventricular ejection fraction measured by angiocardiography, difference of the longitudinal variation between groups was significant （P=0.046）. Early diasto

关键词： myocardial infarction granulocyte colony-stimulating factor angiocardiography echocardiography stem cells

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本科层次职业教育的价值、困境和策略

成人教育 2022年第6期42卷 63-68页

作者：程舒通徐从富杭州科技职业技术学院物联网技术学院杭州311402 浙江大学计算机科学与技术学院杭州310027

本科层次职业教育是职业教育迈向提质培优、增值赋能的必经之路,因为这种类型的教育存在四个方面的价值,分别是在教育分层中扭转职业教育被动的地位、完善职业教育体系的生态结构、提高职业教育的科研能力与社会服务能力、满足国民经济... 详细信息

本科层次职业教育是职业教育迈向提质培优、增值赋能的必经之路,因为这种类型的教育存在四个方面的价值,分别是在教育分层中扭转职业教育被动的地位、完善职业教育体系的生态结构、提高职业教育的科研能力与社会服务能力、满足国民经济发展对职业教育的需求。在本科层次职业教育建设的过程中,存在六个难点与困境,分别为缺乏完善的政策支持、缺乏健全的法律保障、缺乏科学的办学指标、缺乏明确的培养目标、缺乏学位制度、缺乏有效的考试招生方式。针对每个难点与困境,提出相应的解决措施。

关键词：职业教育本科层次学位建设办学指标考试招生

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羟基磷灰石生物涂层的复合制备与生物相容性

无机材料学报 2001年第3期16卷 522-528页

作者：付涛张玉梅憨勇徐可为 xu Ke-Wei 西安交通大学金属材料强度国家重点实验室西安710049 西安交通大学第四军医大学口腔医院修复科 State Key Laboratory for Mechenical Behavior of Materials Xi'an Jiaotong University

采用等离子喷涂ＣａＨＰＯ４和水热处理复合制备羟基磷灰石生物涂层，研究了羟基磷灰石涂层的结合强度和溶解性，用成骨细胞考察了生物相容性．结果表明：喷涂涂层由ＣａＨＰＯ４、β－Ｃａ２Ｐ２Ｏ７和α－Ｃａ３（ＰＯ４）２组成，其... 详细信息

采用等离子喷涂ＣａＨＰＯ４和水热处理复合制备羟基磷灰石生物涂层，研究了羟基磷灰石涂层的结合强度和溶解性，用成骨细胞考察了生物相容性．结果表明：喷涂涂层由ＣａＨＰＯ４、β－Ｃａ２Ｐ２Ｏ７和α－Ｃａ３（ＰＯ４）２组成，其相比例、结晶性和形貌取决于喷涂电流和喷涂距离；喷涂涂层经过水热处理可转化为针状结晶的缺钙羟基磷灰石；这种羟基磷灰石涂层具有高的结合强度和稳定性，与成骨细胞的生物相容性良好．

关键词：羟基磷灰石生物涂层等离子喷涂水热合成细胞实验生物材料生物相容性