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基于APCS-MLR模型的西藏茶巴朗湿地表层沉积物重金属分布特征及来源解析
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作者 李伟 杨博 +3 位作者 熊健 谢鹏程 张娜 吕学斌 《冰川冻土》 CSCD 2024年第4期1356-1368,共13页
湿地作为介于水体和陆地之间的第三生态系统,有着重要的生态功能。由于特殊的地理位置和自然环境条件,西藏地区形成了众多独具特色的天然高原湿地,在拉萨河流域湿地聚集现象尤为显著,茶巴朗湿地就是该流域的重要成员之一。近年来,随着... 湿地作为介于水体和陆地之间的第三生态系统,有着重要的生态功能。由于特殊的地理位置和自然环境条件,西藏地区形成了众多独具特色的天然高原湿地,在拉萨河流域湿地聚集现象尤为显著,茶巴朗湿地就是该流域的重要成员之一。近年来,随着城市旅游业、农牧业大力发展,湿地面积、动植物资源丰富度和湿地功能等方面出现了不同程度的退化。为了解西藏茶巴朗湿地表层沉积物的重金属分布特征与污染状况,于2021年8月共采集湿地表层沉积物样品19个,分别测定了沉积物样品中重金属含量,同时利用内梅罗污染指数和潜在生态风险指数对研究区重金属污染现状进行评价,并通过绝对主成分得分-多元线性回归模型(APCS-MLR)进行重金属来源解析。结果发现,茶巴朗湿地表层沉积物中Cu、Cr、Ni、Zn、Pb、Cd、As和Hg元素含量分别是西藏背景值的1.71、0.56、0.65、1.02、1.31、1.52、0.92、1.48倍,但远低于《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018)中筛选值,与西藏其他高原湿地相比,沉积物重金属富集水平较低;研究区内梅罗污染指数均值为1.68,属轻度污染水平;潜在生态风险指数RI均值为134.45,属于轻微生态风险。绝对主成分得分-多元线性回归模型结果表明,茶巴朗湿地沉积物中Cu、Zn、Pb、Hg来源于交通运输和农业活动混合源,Cr、Ni来源于土壤母质源,As来源于地热源,Cd来源于地热源、交通运输和农业活动混合源,研究区湿地的沉积物重金属主要影响途径为交通运输和农业活动混合输入。本研究揭示了茶巴朗湿地沉积物中重金属元素的赋存现状、空间分布特征和生态风险等级,以及重金属的可能来源,客观了解湿地环境质量现状,为茶巴朗湿地和其他区域高原湿地后续的污染防治工作和可持续发展提供科学依据和理论支撑。 展开更多
关键词 茶巴朗湿地 沉积物 重金属 分布特征 风险评价 apcS-MLR
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后插入钢筋位置等对Ⅱ型APC接头拉伸性能影响
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作者 余琼 陈劲松 +4 位作者 唐子鸣 郭霖 谢青海 张志 陈振海 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第10期101-114,共14页
为探究后插入钢筋位置等对Ⅱ型套筒灌浆搭接接头(简称APC接头)受力性能的影响,对36个接头进行单向拉伸试验,分析试件破坏形式、极限承载力、延性与套筒应变等,并利用ABAQUS进行数值模拟。结果表明:防偏转措施有效提高试件的极限承载力... 为探究后插入钢筋位置等对Ⅱ型套筒灌浆搭接接头(简称APC接头)受力性能的影响,对36个接头进行单向拉伸试验,分析试件破坏形式、极限承载力、延性与套筒应变等,并利用ABAQUS进行数值模拟。结果表明:防偏转措施有效提高试件的极限承载力和初始刚度;接头承载力和延性主要受3种因素影响,即钢筋间距、后插入钢筋偏心程度及是否紧贴套筒布置;后插入钢筋布置于套筒中部,钢筋间距大,套筒长边约束弱,接头承载力和延性降低;后插入钢筋偏心布置,易产生弯曲变形,接头承载力和延性降低;后插入钢筋紧贴套筒布置易产生灌浆缺陷,接头承载力和延性降低;两钢筋紧贴对称布置于长轴时,接头承载力和延性最大;极限荷载时,套筒短边侧纵向应变为拉应变,但存在受压趋势,套筒长边侧纵向应变为压应变;套筒长边侧环向应变绝对值基本大于短边侧,小于套筒屈服应变。模拟试件的破坏形态、极限承载力等与试验结果吻合较好,验证了模型的可靠性。钢筋位置不同时,极限荷载最小值约为最大值的80%。 展开更多
关键词 Ⅱ型apc接头 搭接连接 钢筋位置 拉伸性能 数值模拟
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1990-2019年中国结直肠癌发病与死亡趋势的APC模型分析 被引量:1
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作者 朱广涵 刘雪薇 +2 位作者 韦丹梅 朱云 王媛 《中国卫生统计》 CSCD 北大核心 2024年第2期218-222,共5页
目的评估1990-2019年中国结直肠癌发病与死亡趋势,为降低结直肠癌疾病负担提供科学依据。方法本研究采用年龄-时期-队列(age-period-cohort,APC)模型,分析2019年全球疾病负担(global burden of disease study,GBD2019)数据库中1990-201... 目的评估1990-2019年中国结直肠癌发病与死亡趋势,为降低结直肠癌疾病负担提供科学依据。方法本研究采用年龄-时期-队列(age-period-cohort,APC)模型,分析2019年全球疾病负担(global burden of disease study,GBD2019)数据库中1990-2019年中国结直肠癌发病率和死亡率的数据。结果1990-2019年中国结直肠癌发病/死亡率总体呈现上升趋势。APC模型分析结果显示:我国结直肠癌的发病与死亡风险的年龄效应随着年龄的增长而增加。结直肠癌发病风险的队列效应总体呈上升趋势,死亡风险队列效应呈现先上升后下降趋势。结直肠癌发病风险的时期效应总体呈上升趋势,死亡风险的时期效应呈先下降后上升再下降趋势。结论由于年龄、时期和队列效应的影响,中国居民1990-2019年结直肠癌发病率和死亡率均呈上升趋势,且结直肠癌发病的风险在60~70年龄段增长速度最快。这提示我们,有必要加强结直肠癌相关健康教育,尤其是中老年群体的健康干预,进而预防结直肠癌的发生,减轻疾病给个人、家庭和社会带来的负担。 展开更多
关键词 结直肠癌 发病 死亡 apc模型
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基于Count Sketch的预处理贪婪Kaczmarz方法
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作者 叶雨欣 殷俊锋 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期1305-1311,共7页
在贪婪Kaczmarz方法中,通过对系数矩阵进行正交三角分解引入右预处理子能够提高贪婪Kaczmarz方法的收敛速率。但在系数矩阵的行数远大于列数的情况下,正交三角分解的成本过高。为降低预处理的成本,通过引入Count Sketch变换,提出了基于C... 在贪婪Kaczmarz方法中,通过对系数矩阵进行正交三角分解引入右预处理子能够提高贪婪Kaczmarz方法的收敛速率。但在系数矩阵的行数远大于列数的情况下,正交三角分解的成本过高。为降低预处理的成本,通过引入Count Sketch变换,提出了基于Count Sketch的预处理贪婪Kaczmarz方法,并对新方法进行了收敛性分析。理论分析说明了新方法在系数矩阵条件数较大时比已有方法具有更好的收敛速率。数值实验验证了新方法的有效性。 展开更多
关键词 Kaczmarz方法 预处理 count Sketch 收敛性
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Apc⁃Kras⁃Cre肠腺瘤转基因小鼠模型构建
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作者 陈苇善 汪舒云 +4 位作者 袁路云 王皓月 孙可向 高嘉敏 邓皖利 《中国比较医学杂志》 CAS 北大核心 2024年第7期60-67,156,共9页
目的探讨构建Apc⁃Kras⁃Cre肠腺瘤小鼠模型最佳他莫昔芬诱导方式,建立小鼠模型。方法以C57BL/6J野生型小鼠为健康的对照组。以不同浓度、剂量、给药时长他莫昔芬腹腔注射于转基因小鼠,即组1以低剂量他莫昔芬(5 mg/kg)给药1 d,组2以低剂... 目的探讨构建Apc⁃Kras⁃Cre肠腺瘤小鼠模型最佳他莫昔芬诱导方式,建立小鼠模型。方法以C57BL/6J野生型小鼠为健康的对照组。以不同浓度、剂量、给药时长他莫昔芬腹腔注射于转基因小鼠,即组1以低剂量他莫昔芬(5 mg/kg)给药1 d,组2以低剂量他莫昔芬(5 mg/kg)给药3 d,组3以高剂量他莫昔芬(50 mg/kg)给药1 d,组4以高剂量他莫昔芬(50 mg/kg)给药3 d,给药4周后观察各组小鼠生存率、体重变化,药物诱导4周后观察各组小鼠肠道长度变化、肠内腺瘤生长数量以及大小,再通过苏木精伊红染色、显微镜下观察肠道组织、腺瘤的生理情况。结果第一部分实验发现雌鼠生存率低于雄鼠(P<0.001),死亡率高于雄鼠(P<0.05),各组不同浓度与剂量之间比较生存率差异具有统计学意义(P<0.01)。各组小鼠体重变化与对照组相比差异具有统计学意义(P<0.001),组1与组2,组2与组3,组1与组4之间差异各具统计学意义(P<0.001,P<0.01,P<0.05)。各组小鼠大肠长度与对照组相比未具统计学意义(P>0.05),组1与组3差异具有统计学意义(P<0.05)。各组小鼠大肠内都长有腺瘤,多数于结肠远端,组3与组4腺瘤较多也较大。给药组小鼠大肠病理情况与健康对照组相比出现腺瘤生长,腺体组织排列紊乱、上皮细胞排列不齐,肠道黏膜屏障松散,隐窝分歧不规则,组3、组4也有炎症发生,组4部分区域发现细胞坏死。结论他莫昔芬诱导Apc⁃Kras⁃Cre肠腺瘤转基因小鼠造模成功,并且由此判断,他莫昔芬浓度10 mg/mL、5 mg/kg的剂量诱导1 d的诱导方式最为合适。 展开更多
关键词 肠腺瘤 apc基因 KRAS基因 动物模型 小鼠
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先进控制系统APC+2.0在聚乙烯装置操作优化中的应用 被引量:1
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作者 梅智鹏 《合成树脂及塑料》 CAS 北大核心 2024年第2期59-65,共7页
先进控制系统APC+2.0投用后使聚乙烯装置可靠性、产品质量控制、牌号切换控制都有较大提升,但在运行测试期间出现产品质量稳定性波动和切换牌号波动的问题。通过对测试数据进行分析,优化了配方参数和操作方案。运行效果表明:优化后的APC... 先进控制系统APC+2.0投用后使聚乙烯装置可靠性、产品质量控制、牌号切换控制都有较大提升,但在运行测试期间出现产品质量稳定性波动和切换牌号波动的问题。通过对测试数据进行分析,优化了配方参数和操作方案。运行效果表明:优化后的APC+2.0显著提升了最大加工负荷,降低了切换牌号时副牌号产品数量,减少了异戊烷消耗量,降低了操作强度,提升了产品质量稳定性,实现了产品价值的优化目标,为装置持续带来经济效益。 展开更多
关键词 聚乙烯 先进控制系统apc+2.0 运行难题 操作优化 运行效果
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基于PCA-APCS-MLR模型的滇池流域地下水质量影响因素定量识别
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作者 彭聪 梁建宏 +3 位作者 任坤 曾洁 唐薇薇 潘晓东 《环境科学研究》 CAS CSCD 北大核心 2024年第5期1116-1126,共11页
近年来,随着人类活动的加剧,滇池流域地下水质量不断恶化.本研究在评价流域地下水质量及主要影响指标的基础上,利用主成分分析法(PCA)归纳主要影响水质的驱动因子,并结合绝对主成分得分-多元线性回归受体模型(APCS-MLR模型)进一步量化... 近年来,随着人类活动的加剧,滇池流域地下水质量不断恶化.本研究在评价流域地下水质量及主要影响指标的基础上,利用主成分分析法(PCA)归纳主要影响水质的驱动因子,并结合绝对主成分得分-多元线性回归受体模型(APCS-MLR模型)进一步量化了人为和天然因素对流域内地下水质量的影响程度.结果表明:①滇池流域约78%的地下水超过GB/T 14848-2017《地下水质量标准》Ⅲ类水标准,其中主要超标指标为铝(Al)、锰(Mn)和总铁(TFe).②通过主成分分析(PCA)提取了5类影响水质的主成分因子,分别为水岩相互作用因子(24.27%)、生活污水漏排因子(17.09%)、农业活动污染因子(12.24%)、地质环境背景因子(10.26%)和工业活动污染因子(9.14%),方差累积贡献率为73.00%.③利用APCS-MLR模型进一步量化了各类人为和天然因素对流域内地下水质量影响的贡献,5项因子对特征指标的平均贡献率分别为45.15%、70.76%、45.54%、54.1%和44.59%.研究显示,人类活动对地下水的过度开采及工农业活动是导致区域地下水质量下降的主要因素. 展开更多
关键词 滇池流域 地下水质量 污染源识别 PCA apcS-MLR模型
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基于APCS-MLR受体模型的弹药销毁场土壤重金属源解析
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作者 毕永顺 朱勇兵 +6 位作者 刘祖文 赵三平 张言 聂果 郇正来 田帅 左华伟 《环境化学》 CAS CSCD 北大核心 2024年第7期2313-2324,共12页
为了掌握弹药销毁场重金属污染状况与来源,以山西某典型弹药销毁场为例,对该销毁场39个表层土壤重金属(Cr、Ni、Cu、Zn、As、Cd、Sb、Pb)的污染状况、分布特征与污染来源进行评价与分析.结果表明,弹壳堆放区表层土壤重金属Cr、Ni、Cu、Z... 为了掌握弹药销毁场重金属污染状况与来源,以山西某典型弹药销毁场为例,对该销毁场39个表层土壤重金属(Cr、Ni、Cu、Zn、As、Cd、Sb、Pb)的污染状况、分布特征与污染来源进行评价与分析.结果表明,弹壳堆放区表层土壤重金属Cr、Ni、Cu、Zn、As、Cd、Sb、Pb的平均含量分别为45.57、23.43、325.54、265.43、9.53、0.42、304.17、13174.29 mg·kg^(-1),其余区域表层土壤重金属Cr、Ni、Cu、Zn、As、Cd、Sb、Pb的平均含量分别为102.09、26.75、1137.18、3007.13、7.71、0.95、70.65、2894.97 mg·kg^(-1),均高于山西省背景值.污染指数评价结果表明,Pb、Zn、Cu、Sb和Cd的累积程度较高.研究区土壤重金属生态危害指数为2653.35,达到极高生态风险水平.绝对主成分得分-多元线性回归模型(APCS-MLR)表明,Ni、Cd、Zn、Cr和Cu的来源主要为混合源,贡献率为72.94%,Pb和Sb的主要来源是销毁源,贡献率为53.99%,自然源对As贡献率最大,为44.63%. 展开更多
关键词 弹药销毁场 重金属 污染特征 潜在生态风险 apcS-MLR受体模型
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APC在直吹式煤粉炉控制系统的应用研究
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作者 党启柏 李磊 +4 位作者 郭艳林 徐继友 李伟 刘成 徐江 《山东化工》 CAS 2024年第4期242-244,251,共4页
直吹式煤粉炉燃烧系统具有非线性、滞后性以及强耦合性等特点。常规自动化控制只适用于一定负荷条件下,而对变负荷及煤质变化等适应性差,不能满足用气负荷变化速度。APC(Advanced Process Control)先进过程控制[1]系统的出现,大大改善... 直吹式煤粉炉燃烧系统具有非线性、滞后性以及强耦合性等特点。常规自动化控制只适用于一定负荷条件下,而对变负荷及煤质变化等适应性差,不能满足用气负荷变化速度。APC(Advanced Process Control)先进过程控制[1]系统的出现,大大改善了传统PID控制[2]的控制效果,使优化结果始终处于安全允许的范围内,确保煤粉锅炉及发电系统运行安全性,同时,根据负荷和煤质的变化,优化配风和给煤,使锅炉系统有较高的运行效率。 展开更多
关键词 直吹式煤粉炉 apc(先进过程控制) 控制
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基于APCS-MLR模型的煤矿开采对地下水的影响定量识别
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作者 刘基 高敏 +1 位作者 陈引锋 靳德武 《中国煤炭地质》 2024年第10期45-51,44,共8页
中国煤炭与水资源储量呈逆向分布,煤炭基地水资源相对短缺,生态环境脆弱。随着煤炭资源的大规模和高强度开发,区域地下水环境问题越发凸显。为定量识别煤矿开采对地下水的影响程度,以蒙东能源基地某矿区为例,通过采集矿区周边地下水化... 中国煤炭与水资源储量呈逆向分布,煤炭基地水资源相对短缺,生态环境脆弱。随着煤炭资源的大规模和高强度开发,区域地下水环境问题越发凸显。为定量识别煤矿开采对地下水的影响程度,以蒙东能源基地某矿区为例,通过采集矿区周边地下水化学样品进行测试,系统分析了研究区地下水水化学特征,采用相关性分析、PCA等多元统计方法确定了地下水的影响因子,据此建立了基于绝对因子得分-多元线性回归法(APCS-MLR)的定量识别模型,对研究区地下水受煤矿开采的影响贡献进行了计算分析。结果显示:研究区浅层地下水pH值为6.52~7.86,平均7.27,TDS为126.14~2240.34mg/L,平均为638.18 mg/L。主要阳离子平均含量Na^(+)>Ca^(2+)>Mg^(2+)>K^(+),主要阴离子平均含量HCO_(3)^(-)>Cl^(-)>SO_(4)^(2-)>NO_(3)^(-)。其中Cl^(-)和SO_(4)^(2-)的含量分别为4.25~779.77 mg/L和0~483.20 mg/L,其变异系数均大于100%。SO_(4)^(2-)与Na^(+)、Ca^(+)、Mg^(2+)、Cl^(-)存在显著正相关关系(r>0.72,P<0.01),TDS与SO_(4)^(2-)、Na^(+)、Ca^(+)、Mg^(2+)、Cl^(-)存在显著正相关关系。多项指标显示研究区地下水水质已经受到了煤矿开采的影响。主成分分析(PCA)解析了4个地下水影响因子,分别为煤炭开采影响因子、自然因素的硅酸盐溶解因子、自然因素的反硝化作用和农业活动的化肥使用,其占总荷载的37.061%、16.067%、14.807%和8.775%。以SO_(4)^(2-)作为煤矿开采对地下水影响的表征因子,构建了SO_(4)^(2-)来源计算分析的APCS-MLR定量识别模型。通过最小二乘法计算得到模型的各项参数,确定SO_(4)^(2-)的实际浓度和预测浓度拟合曲线为y=0.9716x+2.9702(R^(2)=0.9759),说明构建的回归方程符合实际,效果良好。据此计算了4个地下水影响因子的贡献比分别为79.3%、6.06%、2.00%和9.96%,其他未识别的因子占比2.67%。分析了煤矿开采影响地下水水质的主要方式为形成降落漏斗影响周边水化学场以及外排含有特殊组分的矿井水进而影响地下水水质。因此需要采取合理措施控制煤矿开采产生的降落漏斗范围继续扩大,必要时对已经产生的漏斗进行恢复治理,同时加强对高盐、高SO_(4)^(2-)矿井水的处理和排放管理,研究成果可为煤炭绿色开发和环境高质量发展提供技术支持。 展开更多
关键词 煤矿开采 地下水 绝对因子得分-多元线性回归(apcS-MLR) 定量识别 影响因子
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Lightweight Res-Connection Multi-Branch Network for Highly Accurate Crowd Counting and Localization
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作者 Mingze Li Diwen Zheng Shuhua Lu 《Computers, Materials & Continua》 SCIE EI 2024年第5期2105-2122,共18页
Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges i... Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges including crowd multi-scale variations and high network complexity,etc.To tackle these issues,a lightweight Resconnection multi-branch network(LRMBNet)for highly accurate crowd counting and localization is proposed.Specifically,using improved ShuffleNet V2 as the backbone,a lightweight shallow extractor has been designed by employing the channel compression mechanism to reduce enormously the number of network parameters.A light multi-branch structure with different expansion rate convolutions is demonstrated to extract multi-scale features and enlarged receptive fields,where the information transmission and fusion of diverse scale features is enhanced via residual concatenation.In addition,a compound loss function is introduced for training themethod to improve global context information correlation.The proposed method is evaluated on the SHHA,SHHB,UCF-QNRF and UCF_CC_50 public datasets.The accuracy is better than those of many advanced approaches,while the number of parameters is smaller.The experimental results show that the proposed method achieves a good tradeoff between the complexity and accuracy of crowd counting,indicating a lightweight and high-precision method for crowd counting. 展开更多
关键词 Crowd counting Res-connection multi-branch compound loss function
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Sensitivity of diagnosis of spontaneous bacterial peritonitis is higher with the automated cell count method
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作者 Juan G Acevedo-Haro Waddah Mohamed +8 位作者 Prebashan Moodley Oliver Bendall Kris Bennett Nigel Keelty Sally Chan Sam Waddy Joanne Hosking Wayne Thomas Robert Tilley 《World Journal of Hepatology》 2024年第11期1265-1281,共17页
BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection ... BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis. 展开更多
关键词 Spontaneous bacterial peritonitis DIAGNOSIS CIRRHOSIS Bacterial infection Automated cell count method Manual cell count method Ascitic fluid
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Deep Learning Based Efficient Crowd Counting System
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作者 Waleed Khalid Al-Ghanem Emad Ul Haq Qazi +1 位作者 Muhammad Hamza Faheem Syed Shah Amanullah Quadri 《Computers, Materials & Continua》 SCIE EI 2024年第6期4001-4020,共20页
Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different events.It is challenging to determine the approximate crowd size from an ima... Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different events.It is challenging to determine the approximate crowd size from an image of the crowd’s density.Therefore in this research study,we proposed a multi-headed convolutional neural network architecture-based model for crowd counting,where we divided our proposed model into two main components:(i)the convolutional neural network,which extracts the feature across the whole image that is given to it as an input,and(ii)the multi-headed layers,which make it easier to evaluate density maps to estimate the number of people in the input image and determine their number in the crowd.We employed the available public benchmark crowd-counting datasets UCF CC 50 and ShanghaiTech parts A and B for model training and testing to validate the model’s performance.To analyze the results,we used two metrics Mean Absolute Error(MAE)and Mean Square Error(MSE),and compared the results of the proposed systems with the state-of-art models of crowd counting.The results show the superiority of the proposed system. 展开更多
关键词 Crowd counting EfficientNet multi-head attention convolutional neural network transfer learning
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Rapid Detection of Somatic Cell Count Based on Hybrid Variable Selection Method
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作者 Shen Weizheng Cui Xiang +6 位作者 Wang Yan Nie Debao Zhang Qinggang Zheng Wei Sun Jian Yang Xin Dai Baisheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期59-73,共15页
Somatic cell count detection is the daily work of dairy farms to monitor the health of cows.The feasibility of applying near-infrared spectroscopy to somatic cell count detection was researched in this paper.Milk samp... Somatic cell count detection is the daily work of dairy farms to monitor the health of cows.The feasibility of applying near-infrared spectroscopy to somatic cell count detection was researched in this paper.Milk samples with different somatic cell counts were collected and preprocessing methods were studied.Variable selection algorithm based on hybrid strategy and modelling method based on ensemble learning were explored for somatic cell count detection.Detection model was used to diagnose subclinical mastitis and the results showed that near-infrared spectroscopy could be a tool to realize rapid detection of somatic cell count in milk. 展开更多
关键词 near-infrared spectroscopy somatic cell count MASTITIS rapid detection
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A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM
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作者 Yili Wang Changsheng Li Xiaofeng Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期463-474,共12页
When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ... When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of layers.To address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent network.By leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration process.The analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,respectively.The model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target plates.The maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed model.Moreover,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves. 展开更多
关键词 Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion
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Platelet counts to spleen diameter ratio:A promising noninvasive tool for predicting esophageal varices in cirrhosis patients
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作者 Getnet Yigzaw Mossie Abdulsemed Mohammed Nur +2 位作者 Zekarias Seifu Ayalew Gebeyehu Tessema Azibte Kaleb Assefa Berhane 《World Journal of Hepatology》 2024年第10期1177-1187,共11页
BACKGROUND Liver cirrhosis is the end stage of progressive liver fibrosis as a consequence of chronic liver inflammation,wherein the standard hepatic architecture is replaced by regenerative hepatic nodules,which even... BACKGROUND Liver cirrhosis is the end stage of progressive liver fibrosis as a consequence of chronic liver inflammation,wherein the standard hepatic architecture is replaced by regenerative hepatic nodules,which eventually lead to liver failure.Cirrhosis without any symptoms is referred to as compensated cirrhosis.Complications such as ascites,variceal bleeding,and hepatic encephalopathy indicate the onset of decompensated cirrhosis.Gastroesophageal varices are the hallmark of clini-cally significant portal hypertension.AIM To determine the accuracy of the platelet count-to-spleen diameter(PC/SD)ratio to evaluate esophageal varices(EV)in patients with cirrhosis.METHODS This retrospective observational study was conducted at Tikur Anbessa Specia-lized Hospital and Adera Medical Center from January 1,2019,to December 30,2023.Data were collected via chart review and direct patient interviews using structured questionnaires.The data were exported to the SPSS software version 26 for analysis and clearance.A receiver operating characteristic curve was plotted for splenic diameter,platelet count,and PC/SD ratio to obtain sensitivity,speci-ficity,positive predictive value,negative predictive value,positive likelihood ratio,and negative likelihood ratio.RESULTS Of the 140 participants,67%were men.Hepatitis B(38%)was the most common cause of cirrhosis,followed by cryptogenic cirrhosis(28%)and hepatitis C(16%).Approximately 83.6%of the participants had endoscopic evidence of EV,whereas 51.1%had gastric varices.Decompensated cirrhosis and PC were associated with the presence of EV with adjusted odds ratios of 12.63(95%CI:3.16-67.58,P=0.001)and 0.14(95%CI:0.037-0.52,P=0.004),respectively.A PC/SD ratio<1119 had a sensitivity of 86.32%and specificity of 70%with area under the curve of 0.835(95%CI:0.736-0.934,P<0.001).CONCLUSION A PC/SD ratio<1119 predicts EV in patients with cirrhosis.It is a valuable,noninvasive tool for EV risk assess-ment in resource-limited settings. 展开更多
关键词 Cirrhosis Esophageal varices Portal hypertension Platelet count Splenic diameter
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多晶硅精馏塔的基础控制优化及APC控制器应用
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作者 严华 白瑞亭 《化工自动化及仪表》 CAS 2024年第4期719-724,共6页
为提高多晶硅精馏塔生产的自控率和控制精度,确保运行稳定性并降低能耗,采用先进过程控制(APC)实施控制性能优化。通过对基础控制回路PID参数自适应优化,提升生产装置自动化水平,并对精馏粗分塔进行系统性控制性能优化,提升主要过程参... 为提高多晶硅精馏塔生产的自控率和控制精度,确保运行稳定性并降低能耗,采用先进过程控制(APC)实施控制性能优化。通过对基础控制回路PID参数自适应优化,提升生产装置自动化水平,并对精馏粗分塔进行系统性控制性能优化,提升主要过程参数的控制品质,提升再生效率并降低蒸汽消耗量,从而提高现场装置运行平稳性,节约生产运行成本。 展开更多
关键词 apc 多晶硅精馏塔 控制性能优化 PID控制回路
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Diagnostic significance of complete blood cell count and hemogramderived markers for neonatal sepsis at Southwest Public Hospitals,Ethiopia
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作者 Dereje Abebe Regassa Rahel Shumi Nagaash +1 位作者 Bisirat Fikadu Habtu Woyesa Beyene Haile 《World Journal of Clinical Pediatrics》 2024年第2期114-126,共13页
BACKGROUND Neonatal sepsis is defined as an infection-related condition characterized by signs and symptoms of bacteremia within the first month of life.It is the leading cause of mortality and morbidity among newborn... BACKGROUND Neonatal sepsis is defined as an infection-related condition characterized by signs and symptoms of bacteremia within the first month of life.It is the leading cause of mortality and morbidity among newborns.While several studies have been conducted in other parts of world to assess the usefulness of complete blood count parameters and hemogram-derived markers as early screening tools for neonatal sepsis,the associations between sepsis and its complications with these blood parameters are still being investigated in our setting and are not yet part of routine practice.AIM To evaluate the diagnostic significance of complete blood cell count hemogramderived novel markers for neonatal sepsis among neonates attending public hospitals in the southwest region of Oromia,Ethiopia,through a case control study.METHODS A case control study was conducted from October 2021 to October 2023 Sociodemographic,clinical history,and laboratory test results data were collected using structured questionnaires.The collected data were entered into Epi-data 3.1 version and exported to SPSS-25 for analysis.Chi-square,independent sample ttest,and receiver operator characteristics curve of curve were used for analysis.A P-value of less than 0.05 was considered statistically significant.RESULTS In this study,significant increases were observed in the following values in the case group compared to the control group:In white blood cell(WBC)count,neutrophils,monocyte,mean platelet volume(MPV),neutrophils to lymphocyte ratio,monocyte to lymphocyte ratio(MLR),red blood cell width to platelet count ratio(RPR),red blood width coefficient variation,MPV to RPR,and platelet to lymphocyte ratio.Regarding MLR,a cut-off value of≥0.26 was found,with a sensitivity of 68%,a specificity of 95%,a positive predictive value(PPV)of 93.2%,and a negative predictive value(NPV)of 74.8%.The area under the curve(AUC)was 0.828(P<0.001).For WBC,a cutoff value of≥11.42 was identified,with a sensitivity of 55%,a specificity of 89%,a PPV of 83.3%,and a NPV of 66.4%.The AUC was 0.81(P<0.001).Neutrophils had a sensitivity of 67%,a specificity of 81%,a PPV of 77.9%,and a NPV of 71.1%.The AUC was 0.801,with a cut-off value of≥6.76(P=0.001).These results indicate that they were excellent predictors of neonatal sepsis diagnosis.CONCLUSION The findings of our study suggest that certain hematological parameters and hemogram-derived markers may have a potential role in the diagnosis of neonatal sepsis. 展开更多
关键词 Complete blood count Hemogram-derived marker NEONATE SEPSIS Ethiopia
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疏肝和胃方对APC术后溃疡患者的临床疗效
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作者 俞巧燕 施斌程 胡艳艳 《中成药》 CAS CSCD 北大核心 2024年第4期1416-1418,共3页
目的 探讨疏肝和胃方对消化内镜氩离子凝固术(APC)术后溃疡患者的临床疗效。方法 80例患者随机分为对照组和观察组,每组40例,对照组给予雷贝拉唑,观察组在对照组基础上加用疏肝和胃方,疗程6周。检测临床疗效、中医证候评分、GAS、MTL、... 目的 探讨疏肝和胃方对消化内镜氩离子凝固术(APC)术后溃疡患者的临床疗效。方法 80例患者随机分为对照组和观察组,每组40例,对照组给予雷贝拉唑,观察组在对照组基础上加用疏肝和胃方,疗程6周。检测临床疗效、中医证候评分、GAS、MTL、细胞因子(CRP、TNF-α、IL-6)变化。结果 观察组总有效率高于对照组(P<0.05)。治疗后,2组中医证候评分、GAS、细胞因子降低(P<0.05),MTL升高(P<0.05),以观察组更明显(P<0.05)。结论 疏肝和胃方可改善APC术后溃疡患者胃动力学,减轻细胞炎性反应,临床疗效显著。 展开更多
关键词 舒肝和胃方 雷贝拉唑 消化内镜氩离子凝固术(apc) 溃疡
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Blood cell counts and nonalcoholic fatty liver disease: Evidence from Mendelian randomization analysis
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作者 Bin Hu Ai-Hong Wan +7 位作者 Xi-Qiao Xiang Yuan-Hao Wei Yi Chen Zhen Tang Chang-De Xu Zi-Wei Zheng Shao-Ling Yang Kun Zhao 《World Journal of Hepatology》 2024年第8期1145-1155,共11页
BACKGROUND Previous research has highlighted correlations between blood cell counts and chronic liver disease.Nonetheless,the causal relationships remain unknown.AIM To evaluate the causal effect of blood cell traits ... BACKGROUND Previous research has highlighted correlations between blood cell counts and chronic liver disease.Nonetheless,the causal relationships remain unknown.AIM To evaluate the causal effect of blood cell traits on liver enzymes and nonalcoholic fatty liver disease(NAFLD)risk.METHODS Independent genetic variants strongly associated with blood cell traits were extracted from a genome-wide association study(GWAS)conducted by the Blood Cell Consortium.Summary-level data for liver enzymes were obtained from the United Kingdom Biobank.NAFLD data were obtained from a GWAS meta-analysis(8434 cases and 770180 controls,discovery dataset)and the Fingen GWAS(2275 cases and 372727 controls,replication dataset).This analysis was conducted using the inverse-variance weighted method,followed by various sensitivity analyses.RESULTS One SD increase in the genetically predicted haemoglobin concentration(HGB)was associated with aβof 0.0078(95%CI:0.0059-0.0096),0.0108(95%CI:0.0080-0.0136),0.0361(95%CI:0.0156-0.0567),and 0.0083(95%CI:00046-0.0121)for alkaline phosphatase(ALP),alanine aminotransferase(ALT),aspartate aminotransferase,and gammaglutamyl transferase,respectively.Genetically predicted haematocrit was associated with ALP(β=0.0078,95%CI:0.0052-0.0104)and ALT(β=0.0057,95%CI:0.0039-0.0075).Genetically determined HGB and the reticulocyte fraction of red blood cells increased the risk of NAFLD[odds ratio(OR)=1.199,95%CI:1.087-1.322]and(OR=1.157,95%CI:1.071-1.250).The results of the sensitivity analyses remained significant.CONCLUSION Novel causal blood cell traits related to liver enzymes and NAFLD development were revealed through Mendelian randomization analysis,which may facilitate the diagnosis and prevention of NAFLD. 展开更多
关键词 Blood cell counts Liver enzymes Nonalcoholic fatty liver disease Genome-wide association Mendelian randomization study Causal relationship
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