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Relationship between neonatal respiratory distress syndrome pulmonary ultrasonography and respiratory distress score,oxygenation index,and chest radiography grading
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作者 Hai Yang Li-Jun Gao +5 位作者 Jing Lei Qiang Li Liu Cui Xiao-Hua Li Wu-Xuan Yin Sen-Hua Tian 《World Journal of Clinical Cases》 SCIE 2024年第20期4154-4165,共12页
BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a ... BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a less harmful method for assessing the health of neonates with RDS is needed.AIM To analyze the relationships between pulmonary ultrasonography and respiratory distress scores,oxygenation index,and chest X-ray grade of neonatal RDS to identify predictors of neonatal RDS severity.METHODS This retrospective study analyzed the medical information of 73 neonates with RDS admitted to the neonatal intensive care unit of Liupanshui Maternal and Child Care Service Center between April and December 2022.The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest Xray grade of each newborn before and after treatment were collected.Spearman correlation analysis was performed to determine the relationships among these values and neonatal RDS severity.RESULTS The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest X-ray RDS grade of the neonates were significantly lower after treatment than before treatment(P<0.05).Spearman correlation analysis showed that before and after treatment,the pulmonary ultrasonography score of neonates with RDS was positively correlated with the respiratory distress score,oxygenation index,and chest X-ray grade(ρ=0.429–0.859,P<0.05).Receiver operating characteristic curve analysis indicated that pulmonary ultrasonography screening effectively predicted the severity of neonatal RDS(area under the curve=0.805–1.000,P<0.05).CONCLUSION The pulmonary ultrasonography score was significantly associated with the neonatal RDS score,oxygenation index,and chest X-ray grade.The pulmonary ultrasonography score was an effective predictor of neonatal RDS severity. 展开更多
关键词 Neonatal respiratory distress syndrome Pulmonary ultrasonography Ultrasonography score Respiratory distress score Oxygenation index Chest X-ray grading
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基于GIS软件的县级耕地质量等别年度更新评价研究——以松桃县为例 被引量:2
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作者 韩朗 张梦棋 侯敬丽 《国土与自然资源研究》 2024年第1期1-4,共4页
本研究基于GIS软件的空间分析工具,通过选取适宜松桃县的耕地质量等别评定基本参数、评价指标体系及权重,采用“因素法”对2019-2020年度新增、减少类耕地及质量建设耕地等别变化范围进行评定。结果表明,2019-2020年,松桃县减少耕地面积... 本研究基于GIS软件的空间分析工具,通过选取适宜松桃县的耕地质量等别评定基本参数、评价指标体系及权重,采用“因素法”对2019-2020年度新增、减少类耕地及质量建设耕地等别变化范围进行评定。结果表明,2019-2020年,松桃县减少耕地面积871.02 hm^(2),新增耕地159.91 hm^(2),新增耕地等别集中在9~11,质量建设耕地226.26 hm^(2);与“三调”统一时点耕地质量等别成果对比,提升0.01等别。基于本次耕地质量等别成果动态更新,以期为地区实现耕地资源信息的社会化服务及自然资源数量质量并重管理提供参考。 展开更多
关键词 giS 耕地质量等别 更新评价 松桃县
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基于机-热-电多参量信号特征的GIS隔离开关状态评估方法 被引量:4
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作者 周秀 吴旭涛 +3 位作者 田天 白金 张昭宇 李军浩 《电力工程技术》 北大核心 2024年第1期220-228,共9页
气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信... 气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信息对于准确获取其运行状态具有重要意义。文中通过在实体220 kV GIS实验平台上模拟隔离开关最为常见的接触不良缺陷,研究不同接触状态时振动信号、温度变化和局部放电信号的演化规律,获得其与设备状态之间的对应关系,结合健康指数理论和改进层次分析法,提出基于多参量特征的GIS隔离开关综合评估方法。使用该方法开展现场测试,其检查结果与多参量综合评估方法的的分析结果相吻合。文中的研究为GIS隔离开关状态的带电检测提供了一种可行性较高的多参量融合分析新方法。 展开更多
关键词 气体绝缘开关(giS) 隔离开关 振动信号 温度变化 局部放电 健康指数:改进层次分析法
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低GI枸杞杂粮代餐粉的体外消化特性
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作者 田玲丽 马娇 +2 位作者 刘军 范艳丽 刘敦华 《食品工业科技》 CAS 北大核心 2024年第12期342-350,共9页
为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体... 为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体外模拟胃肠消化方法对比分析了各原料粉及代餐粉中蛋白质水解率、总酚含量、黄酮含量及抗氧化活性的变化。结果表明,代餐粉中脂肪和粗纤维含量相较于各原料粉处于偏低水平。各原料粉及代餐粉的高温吸水率为常温吸水率的2倍左右,其中代餐粉吸水率最低(常温条件下吸水率为0.27%±0.05%,高温条件下吸水率为0.59%±0.05%)。代餐粉中快速消化淀粉含量(40.4%±0.003%)及eGI值(23.4)相较于各原料粉均达到最低,而慢消化淀粉和抗性淀粉含量均相对较高。体外模拟胃肠消化实验中,各原料粉及代餐粉蛋白质水解率均逐渐升高且水解主要以胃部为主,其中代餐粉蛋白水解率相对较高;总酚含量在胃肠消化期间均呈上升趋势且代餐粉在消化结束时含量达到最高(7.26 mg/g)。黄酮含量在模拟胃消化过程中明显增加,而在模拟肠消化中含量下降。DPPH自由基和ABTS+自由基清除率在模拟胃消化过程中随时间延长显著(P<0.05)上升,而在模拟肠消化过程中随时间延长呈先上升后降低趋势,但整体变化幅度较为平缓。综上所述,枸杞杂粮代餐粉适合作为低GI原料或产品且具有良好的抗氧化能力,对于杂粮制品的开发具有一定指导的意义。 展开更多
关键词 gi 杂粮 枸杞 代餐粉 体外消化特性
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Compressive near-field millimeter wave imaging algorithm based on Gini index and total variation mixed regularization
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作者 Jue Lyu Dong-Jie Bi +7 位作者 Bo Liu Guo Yi Xue-Peng Zheng Xi-Feng Li Li-Biao Peng Yong-Le Xie Yi-Ming Zhang Ying-Li Bai 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期65-74,共10页
A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-... A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse data.The Gini index(GI)has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood,Scaling,Rising Tide,Cloning,Bill Gates,and Babies.By combining the total variation(TV)operator,the GI-TV mixed regularization introduced compressive near-field MMW imaging model is proposed.In addition,the corresponding algorithm based on a primal-dual framework is also proposed.Experimental results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm. 展开更多
关键词 Millimeter wave(MMW) Compressed sensing(CS) gini index(gi) Total variation(TV) Signal processing Image reconstruction
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时变温差工况下直流GIL/GIS盆式绝缘子动态电场畸变抑制 被引量:2
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作者 杜伯学 姚航 +1 位作者 梁虎成 董佳楠 《电工技术学报》 EI CSCD 北大核心 2024年第9期2851-2859,共9页
为了优化时变温差工况下直流GIL/GIS盆式绝缘子的沿面电场分布,基于表层电导梯度材料(σ-SFGM)设计了以室温(RT)电场均化为目标的RT-SFGM绝缘子与兼顾不同温度梯度(GT)条件的GT-SFGM绝缘子。迭代优化后,RT-SFGM绝缘子的涂层厚度从导体... 为了优化时变温差工况下直流GIL/GIS盆式绝缘子的沿面电场分布,基于表层电导梯度材料(σ-SFGM)设计了以室温(RT)电场均化为目标的RT-SFGM绝缘子与兼顾不同温度梯度(GT)条件的GT-SFGM绝缘子。迭代优化后,RT-SFGM绝缘子的涂层厚度从导体到外壳梯度减小,而GT-SFGM绝缘子的凸面涂层厚度则呈现U型梯度分布。室温条件下,均匀绝缘子的凹面高压三结合点处电场畸变严重,相同位置处的RT-SFGM绝缘子与GT-SFGM绝缘子电场强度分别下降了53.3%和49.5%。随着高压导体温度的上升,绝缘子最大电场位置逐渐向接地外壳附近转移。在40℃温差条件下,GT-SFGM绝缘子的电场畸变抑制效果明显优于RT-SFGM绝缘子,最大电场强度下降59.2%。在负荷加载与负荷波动工况下,GT-SFGM绝缘子的电场变化率分别仅为7%与13.1%,可实现时变温差工况下绝缘子直流电场分布的稳定控制。 展开更多
关键词 直流 giL/giS绝缘子 表面电导梯度材料 时变温差 电场均化
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基于RS与GIS技术的喀斯特煤矿区生态环境质量评价:以盘州市为例 被引量:1
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作者 刘发勇 田祥贵 何林 《中国矿业》 北大核心 2024年第2期63-68,共6页
针对喀斯特煤矿区特殊的地质环境特点,综合考虑影响生态环境质量的因素,选取与煤矿开采活动关联的指标因子,建立喀斯特煤矿区生态环境质量综合评价指标体系。通过对评价指标的分级处理,利用RS与GIS技术对指标因子进行单一评价分析,并在A... 针对喀斯特煤矿区特殊的地质环境特点,综合考虑影响生态环境质量的因素,选取与煤矿开采活动关联的指标因子,建立喀斯特煤矿区生态环境质量综合评价指标体系。通过对评价指标的分级处理,利用RS与GIS技术对指标因子进行单一评价分析,并在ArcGIS栅格数据空间叠加分析计算的支持下,采用综合指数法和层次分析法对盘州市生态环境质量进行综合评价,从而得到盘州市喀斯特煤矿区的生态环境质量等级。评价结果显示,盘州市生态环境质量大部分较好,优良等级占比达75.03%,但部分区域山高坡陡、植被覆盖度低及煤矿开采区相对应的生态环境情况较差;在生态环境保护及经济发展的规划中应以生态环境质量较差的区域为主,加强矿山土地复垦、植树造林等一系列生态恢复措施。在综合评价时引入生态环境质量网格化评价方法,通过一定范围内生态环境质量等级面积及权重的定量计算,为区域生态环境质量评价提供参考。 展开更多
关键词 喀斯特煤矿区 生态环境质量 giS技术 指标体系 生态修复
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Tumour response following preoperative chemotherapy is affected by body mass index in patients with colorectal liver metastases
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作者 Hua-Chuan Song Hang-Cheng Zhou +10 位作者 Ping Gu Bing Bao Quan Sun Tian-Ming Mei Wei Cui Kang Yao Huan-Zhang Yao Shen-Yu Zhang Yong-Shuai Wang Rui-Peng Song Ji-Zhou Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期331-342,共12页
BACKGROUND Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality,with the liver being the primary organ of metastasis.Preoperative chemotherapy is widely recomm... BACKGROUND Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality,with the liver being the primary organ of metastasis.Preoperative chemotherapy is widely recommended for initially or potentially resectable colorectal liver metastases(CRLMs).Tumour pathological response serves as the most important and intuitive indicator for assessing the efficacy of chemotherapy.However,the postoperative pathological results reveal that a considerable number of patients exhibit a poor response to preoperative chemotherapy.Body mass index(BMI)is one of the factors affecting the tumori-genesis and progression of colorectal cancer as well as prognosis after various antitumour therapies.Several studies have indicated that overweight and obese patients with metastatic colorectal cancer experience worse prognoses than those with normal weight,particularly when receiving first-line chemotherapy regimens in combination with bevacizumab.AIM To explore the predictive value of BMI regarding the pathologic response following preoperative chemotherapy for CRLMs.METHODS A retrospective analysis was performed in 126 consecutive patients with CRLM who underwent hepatectomy following preoperative chemotherapy at four different hospitals from October 2019 to July 2023.Univariate and multivariate logistic regression models were applied to analyse potential predictors of tumour pathological response.The Kaplan-Meier method with log rank test was used to compare progression-free survival(PFS)between patients with high and low BMI.BMI<24.0 kg/m^(2) was defined as low BMI,and tumour regression grade 1-2 was defined as complete tumour response.RESULTS Low BMI was observed in 74(58.7%)patients and complete tumour response was found in 27(21.4%)patients.The rate of complete tumour response was significantly higher in patients with low BMI(29.7%vs 9.6%,P=0.007).Multivariate analysis revealed that low BMI[odds ratio(OR)=4.56,95%confidence interval(CI):1.42-14.63,P=0.011],targeted therapy with bevacizumab(OR=3.02,95%CI:1.10-8.33,P=0.033),preoperative carcinoembryonic antigen level<10 ng/mL(OR=3.84,95%CI:1.19-12.44,P=0.025)and severe sinusoidal dilatation(OR=0.17,95%CI:0.03-0.90,P=0.037)were independent predictive factors for complete tumour response.The low BMI group exhibited a significantly longer median PFS than the high BMI group(10.7 mo vs 4.7 mo,P=0.011).CONCLUSION In CRLM patients receiving preoperative chemotherapy,a low BMI may be associated with better tumour response and longer PFS. 展开更多
关键词 Colorectal liver metastases Body mass index Tumour regression grade Preoperative chemotherapy HEPATECTOMY
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基于GIS的滇中地区人居环境适宜性评价
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作者 张雪 刘璐 游珍 《云南地理环境研究》 2024年第1期8-18,共11页
科学评估人居环境适宜性,有助于城市可持续发展,实现人类活动与自然环境和谐共处。研究基于地理信息系统(GIS)技术,以1 km×1 km栅格为基本研究单元,构建了滇中地区地形、水文、植被、气候单要素和综合人居环境适宜性评价模型与标准... 科学评估人居环境适宜性,有助于城市可持续发展,实现人类活动与自然环境和谐共处。研究基于地理信息系统(GIS)技术,以1 km×1 km栅格为基本研究单元,构建了滇中地区地形、水文、植被、气候单要素和综合人居环境适宜性评价模型与标准,从空间上定量评价了滇中地区的人居环境适宜性空间分布特征。研究表明:(1)从自然单要素的适宜性评价结果来看,气候、水文和地被的适宜性评价结果均以比较适宜为主;而地形是该区域人居环境适宜性的主要限制要素,且在空间上分区比较破碎,以一般适宜地区为主,主要分布在区域的西部和北部。(2)从人居环境适宜性综合评价结果来看,整体的人居环境状况较好,空间上呈片状分布的特征,临界适宜和一般适宜地区区域点总面积的80%以上;昆明市的不适宜地区面积占比最高,高度适宜地区面积较小但多数分布在楚雄州,曲靖市整体的人居环境状况最好。(3)结合人口数量和密度空间分布数据来看,人口分布与人居环境适宜性在空间分布上存在较高一致性,滇中地区近90%的人分布在临界适宜、一般适宜和比较适宜地区。 展开更多
关键词 人居环境适宜性 人居环境指数 地理信息系统 滇中地区
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交流GIS/GIL绝缘子介电功能梯度化设计与金属微粒驱离方法研究
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作者 陈田 金洲玉 +2 位作者 胡睿智 梁虎成 杜伯学 《绝缘材料》 CAS 北大核心 2024年第10期133-141,共9页
气体绝缘金属封闭开关(GIS)设备内部的金属微粒污染物会引起严重的电场畸变,进而诱发绝缘子沿面放电。针对此问题,本文提出一种介电功能梯度绝缘子的金属微粒驱离方法,仿真研究盆式绝缘子周围电场分布以及金属微粒运动特性。结果表明:GI... 气体绝缘金属封闭开关(GIS)设备内部的金属微粒污染物会引起严重的电场畸变,进而诱发绝缘子沿面放电。针对此问题,本文提出一种介电功能梯度绝缘子的金属微粒驱离方法,仿真研究盆式绝缘子周围电场分布以及金属微粒运动特性。结果表明:GIS外壳表面释放的金属微粒受到轴向电场力作用,有朝着绝缘子运动的趋势。叠层式功能梯度(ε_(L)-FGM)绝缘子的介电常数沿径向递减,可在均匀沿面电场分布的同时,使金属微粒所受的电场力方向随轴向电场反转,让金属微粒远离绝缘子运动。然而,ε_(L)-FGM绝缘子GIS使外壳表面电场增强,使金属微粒运动高度较均匀绝缘子上增大约2.7倍。与ε_(L)-FGM绝缘子相比,基于拓扑优化算法设计的具有空间介电常数梯度的ε_(T)-FGM绝缘子减小了金属微粒跳跃高度,具有更佳的电场调控与微粒抑制效果。 展开更多
关键词 giS giL 功能梯度材料 沿面电场均化 金属微粒抑制 拓扑优化
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基于GIS的平定县高标准农田耕地质量等级评价研究
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作者 韩佳 李婧 +1 位作者 李海鹰 白建军 《测绘标准化》 2024年第1期96-102,共7页
目前,高标准农田建设工作已在全国范围内取得较好成效,建设完成后每年都需进行耕地质量等级评价,因而对高效、合理、综合评价高标准农田的耕地质量等级工作提出了较高要求。本文结合实际情况,针对多种不同类型数据的指标特征,充分发挥... 目前,高标准农田建设工作已在全国范围内取得较好成效,建设完成后每年都需进行耕地质量等级评价,因而对高效、合理、综合评价高标准农田的耕地质量等级工作提出了较高要求。本文结合实际情况,针对多种不同类型数据的指标特征,充分发挥地理信息系统(GIS)的优势,通过空间连接、Kriging插值、区域统计等数据处理分析方法,将新技术与专业评价方法相结合,形成一套较为完整的数据分析方法体系,提升耕地质量等级评价的效率和准确性。同时,对高标准农田建设中涉及的评价指标进行影响分析,对今后的高标准农田建设具有一定的参考价值。 展开更多
关键词 耕地质量 等级评价 地理信息系统 高标准农田
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基于GIS与层次分析模型的生态旅游舒适度评价方法 被引量:1
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作者 韩燕妮 《桉树科技》 2023年第2期27-34,共8页
为了提升区域范围内的生态旅游质量,针对生态旅游舒适度分析结果片面及冗余性的问题,提出基于地理信息系统(Geographic Information System,GIS)与层次分析(Analytic Hierarchy Process,AHP)模型的生态旅游舒适度评价方法。建立评价指... 为了提升区域范围内的生态旅游质量,针对生态旅游舒适度分析结果片面及冗余性的问题,提出基于地理信息系统(Geographic Information System,GIS)与层次分析(Analytic Hierarchy Process,AHP)模型的生态旅游舒适度评价方法。建立评价指标体系,通过两两对比判断矩阵及方根法确定生态旅游舒适度评价指标的权重值。结果显示:该方法所构建的评价指标体系信度较高,获取生态旅游舒适度评价结果准确,方法可行。 展开更多
关键词 giS 层次分析模型 生态旅游 舒适度评价 指标体系 等级划分图
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The Grey Analysis, Kriging and Selection Index of Flower Yield in Rugosa Rose 被引量:6
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作者 LI Yan-yan FENG Zhen ZHAO Lan-yong MO Zhen-hua ZHANG Bao 《Agricultural Sciences in China》 CAS CSCD 2007年第12期1420-1425,共6页
The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa ro... The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that: The grey relational grade (GRG) of the number of flowers/plant (NF), the number of branches/plant (NB), the width of floral bud (WB), and the weight/flower (WF) to the FY were larger (〉 0.5); FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index (ISI) equation of FY was established with the characters NF, NB, WB, and WF: I= 0.3187x1 - 318.6x2 + 670.1 x4 + 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose. 展开更多
关键词 rugosa rose grey relational grade quantitative traits kriging interpolation index selection
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基于GIS技术的玉米作物种植区主要气象灾害风险评估模型构建
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作者 王洪明 李茂桐 崔兆韵 《现代电子技术》 2023年第19期107-110,共4页
气象灾害风险的综合评估指标选取全面性较差,导致玉米作物种植区气象灾害风险评估准确性较差,为此文中构建基于GIS技术的玉米作物种植区主要气象灾害风险评估模型。基于自然灾害风险形成机制,从气象灾害危险性、暴露性、脆弱性、防灾能... 气象灾害风险的综合评估指标选取全面性较差,导致玉米作物种植区气象灾害风险评估准确性较差,为此文中构建基于GIS技术的玉米作物种植区主要气象灾害风险评估模型。基于自然灾害风险形成机制,从气象灾害危险性、暴露性、脆弱性、防灾能力四个方面选择主要气象灾害风险评价指标,以其归一化处理为前提,通过熵权法完成其权重的计算后,运用GIS技术实现种植区主要气象灾害风险的空间分析,构建主要气象灾害风险评估模型,划分主要气象灾害风险等级,实现气象灾害风险评估模型的构建。实验结果表明,该模型可实现单一、多气象灾害风险评估,有利于玉米作物生长。 展开更多
关键词 giS技术 玉米作物 气象灾害 风险评估模型 防灾减灾 熵权法 归一化 风险指数
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Update of Cultivated Land Quality Grade Based on GIS—A Case Study of a County in Guangxi 被引量:2
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作者 Yuening Song Xiangwen Cai +2 位作者 Mi Tang Yan Zhao Mingyuan Liu 《Open Journal of Soil Science》 2019年第12期243-254,共12页
The quality of cultivated land has an important influence on agricultural output, food security, sustainable development and the ability of using cultivated land resources. As the trend of cultivated land quality is g... The quality of cultivated land has an important influence on agricultural output, food security, sustainable development and the ability of using cultivated land resources. As the trend of cultivated land quality is getting more and more attention, in order to strengthen the management of cultivated land quality, improve the precision of cultivated land quality and other achievements, and maintain the current situation of cultivated land quality and other achievements. For this paper, taking A county of Guangxi Zhuang Autonomous Region as an example, with the support of GIS, the paper studies the grade and grade renewal of cultivated land by using the superposition method, studies the grade and grade change of regional cultivated land and its spatial distribution, grasps the status quo change of cultivated land and the grade and grade change of cultivated land caused by the quality construction of cultivated land in the year, and then provides scientific data for land use plan, land consolidation and cultivates land protection. 展开更多
关键词 CULTIVATED Land Quality GRADE RENEWAL giS A COUNTY GUANGXI
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Leveraging machine learning techniques for predicting pancreatic neuroendocrine tumor grades using biochemical and tumor markers 被引量:1
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作者 Rui-Quan Zhou Hong-Chen Ji +2 位作者 Qu Liu, Chun-Yu Zhu Rong Liu 《World Journal of Clinical Cases》 SCIE 2019年第13期1611-1622,共12页
BACKGROUND The incidence of pancreatic neuroendocrine tumors (PNETs) is now increasing rapidly. The tumor grade of PNETs significantly affects the treatment strategy and prognosis. However, there is still no effective... BACKGROUND The incidence of pancreatic neuroendocrine tumors (PNETs) is now increasing rapidly. The tumor grade of PNETs significantly affects the treatment strategy and prognosis. However, there is still no effective way to non-invasively classify PNET grades. Machine learning (ML) algorithms have shown potential in improving the prediction accuracy using comprehensive data. AIM To provide a ML approach to predict PNET tumor grade using clinical data. METHODS The clinical data of histologically confirmed PNET cases between 2012 and 2018 were collected. A method of minimum P for the Chi-square test was used to divide the continuous variables into binary variables. The continuous variables were transformed into binary variables according to the cutoff value, while the P value was minimum. Four classical supervised ML models, including logistic regression, support vector machine (SVM), linear discriminant analysis (LDA) and multi-layer perceptron (MLP) were trained by clinical data, and the models were labeled with the pathological tumor grade of each PNET patient. The performance of each model, including the weight of the different parameters, were evaluated. RESULTS In total, 91 PNET cases were included in this study, in which 32 were G1, 48 were G2 and 11 were G3. The results showed that there were significant differences among the clinical parameters of patients with different grades. Patients with higher grades tended to have higher values of total bilirubin, alpha fetoprotein, carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 72-4. Among the models we used, LDA performed best in predicting the PNET tumor grade. Meanwhile, MLP had the highest recall rate for G3 cases. All of the models stabilized when the sample size was over 70 percent of the total, except for SVM. Different parameters varied in affecting the outcomes of the models. Overall, alanine transaminase, total bilirubin, carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 72-4 affected the outcome greater than other parameters. CONCLUSION ML could be a simple and effective method in non-invasively predicting PNET grades by using the routine data obtained from the results of biochemical and tumor markers. 展开更多
关键词 Machine learning PANCREATIC NEUROENDOCRINE TUMORS TUMOR grade BIOCHEMICAL indexes TUMOR markers
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Spatial/temporal indexing and information visualization genre for environmental digital libraries 被引量:3
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作者 CHEN Su-shing GRUNWALD Sabine 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1235-1248,共14页
Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities... Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities on ecosystems. Space-time modelling of ecosystems in an environmental digital library is essential for visualizing past, present, and future impacts of changes occurring within such landscapes (e.g., shift in land use practices). In this paper, we describe three novel features, spa- tio-temporal indexing, visualization, and geostatistical genre, for the environmental digital library, Environmental Visualization and Geographic Enterprise System (ENVISAGE), currently in progress at the University of Florida. 展开更多
关键词 Spatio-temporal indexing GEOSTATISTICS giS (Geographic Information System) Visualization Environmentaldigital library Spatio-temporal search
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杂粮的有效利用——低GI(Glycaemic Index)食品的必要性(英文) 被引量:1
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作者 片山直美 《中国粮油学报》 EI CAS CSCD 北大核心 2007年第6期64-70,共7页
研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程... 研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程度与年龄、性别和生理状态有关,在此我们以普通生活的成人作为基准。杂粮中的营养成分,苋的热量358kcal、蛋白质12.7g、脂肪6.0g、糖质64.9g、食物纤维7.4g、Na 1.0mg、P540mg、Fe 9.4mg、Ca 160mg、K 600mg、Cu 0.92mg、Zn 5.8mg、Mn 6.14mg、维生素A 2.0ug以及微量的维生素C。经过研讨设计了营养平衡最佳的食谱为:糙米200g、苋50g、andeskinua50g、大豆110g、甘薯200g、绿黄色蔬菜(小青菜)300g、鸡蛋55g以及泥鳅100g。食用这个食谱可以摄取热量2007 kcal(是基准摄取量的100%),其他营养成分的摄取量与基准摄取量相比分别为:蛋白质173%、脂肪72%、碳水化物105%、K 332%、Ca262%、Mg 267%、P 250%、Fe 420%、Zn 183%、Cu 343%、VA 126%、VD 100%、VE 142%、VK 940%、VB1237%、VB2174%、烟碱酸201%、VB6218%、VB12375%、叶酸350%、泛酸160%、VC 176%、食物纤维185%、盐分5%以及Mn 273%。不足的盐分可以使用调味料来补充。氨基酸的摄取量推测是基准值的100%。蛋白质:脂肪:碳水化物的比例是19.0∶18.0∶63.0,与理想的平衡比接近。 展开更多
关键词 杂粮 gi(Glycaemic index) 营养平衡食物 超重人群
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Modelling of graded index waveguide fabricated by ion exchange on Er^(3+) doped glass 被引量:1
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作者 邵公望 金国良 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期1096-1104,共9页
A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3... A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3+ doped glass. Finite difference method with full-vectorial formulation (FV-FDM) is applied to solving the full-vectorial modes of graded index channel waveguide for the first time. The coupled difference equations based on magnetic fields in FV-FDM are derived from the Taylor series expansion and accurate formulation of boundary conditions. Hybrid nature of vectorial guided modes for both pump (980 nm) and signal light (1550 nm) are demonstrated by the simulation. Results show that the fabrication parameters of ion exchange, such as channel opening width and time ratio of second step to first step in ion exchange, have large influence on the properties of waveguide. By optimizing the fabrication parameters, maintenance of monomode for signal light and improvement of the gain dynamics can be achieved in Er^3+ doped waveguide amplifier (EDWA) fabricated by ion exchange technique. This theoretical model is significant for the design and fabrication of EDWA with ion exchange technique. Furthermore, a single polarization EDWA, which operates at wavelength from 1528 nm to 1541 nm for HE polarization, is numerically designed. 展开更多
关键词 graded index channel waveguide finite difference method full-vectorial mode ion exchange technique
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基于GIS的田间精细化管理——以玉米种业田间种植为例
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作者 段保霞 《智慧农业导刊》 2023年第18期17-20,共4页
该文介绍基于GIS的田间精细化管理平台的设计与实现。以玉米田间种植指标的数字化为基础,采集田间种植过程关键指标数据,获取环境要素信息,对田间空间数据通过GIS进行转换、处理和分析,用以制定种植计划、规范田间管理、保证品种质量、... 该文介绍基于GIS的田间精细化管理平台的设计与实现。以玉米田间种植指标的数字化为基础,采集田间种植过程关键指标数据,获取环境要素信息,对田间空间数据通过GIS进行转换、处理和分析,用以制定种植计划、规范田间管理、保证品种质量、建立种植绩效考核体系及提高工作效率。同时,当进入种子加工厂后,通过产品数字化技术及质量追溯平台,对产品生产加工、包装对应、仓库管理、订单、物流和销售等各个环节的信息进行有效采集、对应和管理,从而进行产品生命周期的全程监控,实现物流跟踪、质量控制及追溯等功能。 展开更多
关键词 giS 种植指标 精细化管理 标准化流程 田间种植
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