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Delineation of an Urban Community life Circle Based on a Machine-Learning Estimation of Spatiotemporal Behavioral Demand

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Chinese Geographical Science 2021年第1期31卷 27-40页

作者： li chunjiang XIA Wanqu CHAI Yanwei College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the life circles. This method, however, is constrained by GPS data, and it can only be applied in the GPS surveyed communities. To address this limitation, this study developed a generalizable delineation method without the constraint of behavioral data. According to previous research, the community life circle consists of the walking-accessible range and internal structure. The core task to develop the generalizable method was to estimate the spatiotemporal behavioral demand for each plot of land to acquire the internal structure of the life circle, as the range can be delineated primarily based on environmental data. Therefore, behavioral demand estimation models were established through logistic regression and machine learning techniques, including decision trees and ensemble learning. The model with the lowest error rate was chosen as the final estimation model for each type of land. Finally, we used a community without GPS data as an example to demonstrate the effectiveness of the estimation models and delineation method. This article extends the existing literature by introducing spatiotemporal behavioral demand estimation models, which learn the relationships between environmental contexts, population composition and the existing delineated results based on GPS data to delineate the internal structure of the community life circle without employing behavioral data. Furthermore, the proposed method and delineation results also contributes to facilities adjustments and location selections in life circle planning, people-oriented transformation in urban planning, and activity space estimation of the population in evaluating and improving the urban policies.

关键词： community life circle spatiotemporal behavioral demand demand estimation model decision tree ensemble learning

Rapid identification of switched systems: A data-driven method in variational framework

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Science China(Technological Sciences) 2021年第1期64卷 148-156页

作者： li chunjiang HUANG ZhiLong WANG Yong JIANG HanQing Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China School for Engineering of Matter Transport and EnergyArizona State UniversityTempe AZ 85287USA

Switched systems, i.e., systems changing the parameter values(even structural forms) abruptly and randomly at arbitrary instants, have been extensively utilized in many fields of modern industries. Rapid identification of switched systems, i.e.,capturing all the changing instants and reconstructing the mathematical models rapidly, is of great significance for behavior prediction, performance evaluation and possible control, but is restricted by small data amount available. Here, the rapid identification problem is successfully solved by a data-driven method in variational framework. The data-driven method only requires a small amount of data due to the compact form of the variational description, and is robust to data noise due to the holistic viewpoint. Two numerical examples, i.e., Duffing oscillator and van der Pol system(as two representative systems in nonlinear dynamics), are adopted to illustrate its application, efficiency and robustness to noise.

关键词： switched system rapid identification data-driven method small data amount robustness

Sodium acetate promotes fat synthesis by suppressing TATA element modulatory factor 1 in bovine mammary epithelial cells

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Animal Nutrition 2023年第2期13卷 126-136页

作者： Chaochao Luo Nan li Qingzhu Wang chunjiang li School of Basic Medical Sciences Jiamusi UniversityJiamusiHeilongjiang154002China College of life Sciences Shihezi UniversityShiheziXinjiang832003China Department of Biochemistry and Molecular Biology School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong510515China Mudanjiang Normal University MudanjiangHeilongjiang157011China Harbin Weike Biotechnology Co. LtdHarbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbinHeilongjiang150069China

Short-chain fatty acids are important nutrients that regulate milk fat synthesis.They regulate milk syn-thesis via the sterol regulatory element binding protein 1(SREBP1)pathway;however,the details are still unknown.Here,the regulation and mechanism of sodium acetate(SA)in milk fat synthesis in bovine mammary epithelial cells(BMECs)were assessed.BMECs were treated with SA supplementation(SAþ)or without SA supplementation(SA-),and milk fat synthesis and activation of the SREBP1 pathway were increased(P=0.0045;P=0.0042)by SAþand decreased(P=0.0068;P=0.0031)by SA-,respectively.Overexpression or inhibition of SREBP1 demonstrated that SA promoted milk fat synthesis(P=0.0045)via the SREBP1 pathway.Overexpression or inhibition of TATA element modulatory factor 1(TMF1)demon-strated that TMF1 suppressed activation of the SREBP1 pathway(P=0.0001)and milk fat synthesis(P=0.0022)activated by SAþ.Overexpression or inhibition of TMF1 and SREBP1 showed that TMF1 suppressed milk fat synthesis(P=0.0073)through the SREBP1 pathway.Coimmunoprecipitation analysis revealed that TMF1 interacted with SREBP1 in the cytoplasm and suppressed the nuclear localization of SREBP1(P=0.0066).The absence or presence of SA demonstrated that SA inhibited the expression of TMF1(P=0.0002)and the interaction between TMF1 and SREBP1(P=0.0001).Collectively,our research sug-gested that TMF1 was a new negative regulator of milk fat synthesis.In BMECs,SA promoted the SREBP1 pathway and milk fat synthesis by suppressing TMF1.This study enhances the current understanding of the regulation of milk fat synthesis and provides new scientific data for the regulation of milk fat synthesis.

关键词： Sodium acetate Milk fat synthesis Sterol regulatory element-binding protein 1 TATA element modulatory factor 1 Bovine mammary epithelial cell

工匠精神融入机械专业人才培养研究——以北华大学为研究样本

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职业技术 2024年第6期23卷 85-90页

作者：李春江王开宝北华大学机械工程学院吉林吉林132013

工科院校是工匠精神人才培育的主体,肩负着重要历史使命。工匠精神将助力实现中国制造新一轮的崛起,将工匠精神融入机械专业人才培养过程是践行社会主义核心价值观的重要体现,也是提升新时期机械专业人才培养质量的时代诉求。文章提出... 详细信息

工科院校是工匠精神人才培育的主体,肩负着重要历史使命。工匠精神将助力实现中国制造新一轮的崛起,将工匠精神融入机械专业人才培养过程是践行社会主义核心价值观的重要体现,也是提升新时期机械专业人才培养质量的时代诉求。文章提出了将工匠精神融入机械职业教育的基础理念,在教育过程中公共课与专业课的课程设置方面注重工匠精神思政教育的实施,从而达到思政教育与专业教育并驾齐驱的预期目标。

关键词：工匠精神课程思政人才培养机械专业

基于模糊数学综合评判优化酸枣仁复合饮料配方

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保鲜与加工 2024年第1期24卷 36-41页

作者：张芳荣陈方会李春江王一婕栾智华杜俊民山西中医药大学中药与食品工程学院山西晋中030619

以酸枣仁、茯苓、薏苡仁、百合和大枣为主要原料,通过模糊数学及正交试验等方法优化酸枣仁复合饮料配方。结果表明,酸枣仁复合饮料的最优配方为:复合澄清汁添加量35%(质量分数,下同),蜂蜜添加量2.4%,柠檬酸添加量0.1%,蔗糖添加量6%,柠... 详细信息

以酸枣仁、茯苓、薏苡仁、百合和大枣为主要原料,通过模糊数学及正交试验等方法优化酸枣仁复合饮料配方。结果表明,酸枣仁复合饮料的最优配方为:复合澄清汁添加量35%(质量分数,下同),蜂蜜添加量2.4%,柠檬酸添加量0.1%,蔗糖添加量6%,柠檬酸钾添加量0.4%;最佳稳定剂组合为:羧甲基纤维素钠(CMC-Na)添加量0.20%,黄原胶添加量0.01%,果胶添加量0.15%。该配方下制得的复合饮料色泽纯正,呈浅黄色,酸甜适宜,状态稳定,富有独特的枣香气。

关键词：酸枣仁复合饮料配方模糊数学法

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食品微生物检验方法的技术验证

现代食品 2024年第3期30卷 162-166页

作者：刘胤璇李春江杨蕊银白秀珍红河哈尼族彝族自治州质量技术监督综合检测中心云南蒙自661199

目的:探讨微生物检验方法技术验证工作程序,为检验检测机构提供借鉴和参考。方法:以副溶血性弧菌检验方法技术验证为例,通过方法验证要素控制,建立食品微生物检验方法技术验证基本模式,从检出水平、估计偏差、精密度、不确定度评定等方... 详细信息

目的:探讨微生物检验方法技术验证工作程序,为检验检测机构提供借鉴和参考。方法:以副溶血性弧菌检验方法技术验证为例,通过方法验证要素控制,建立食品微生物检验方法技术验证基本模式,从检出水平、估计偏差、精密度、不确定度评定等方面对副溶血性弧菌检验方法进行验证。结果:水产制品和水产调味品定性检验检出水平分别为2 CFU/测试单位、3 CFU/测试单位,低于预估检出水平;不同浓度水平的估计偏差分别为0.35 lgCFU·g^(-1)、0.27 lgCFU·g^(-1)、0.24 lgCFU·g^(-1),均小于0.5 lgCFU·g^(-1);重复性标准偏差为0.1138%,小于再现性标准偏差0.18%;方法的扩展不确定度为0.22 lgMPN·g^(-1)(k=2,置信概率为95%)。结论:实验从检出水平、估计偏差、精密度、不确定度评定等方面构建了副溶血性弧菌检测方法验证的基本模式,验证结果满意,同时给出了不确定度评定方案,为实验室制定判定规则提供了参考。

关键词：微生物检验方法技术验证副溶血性弧菌

测试片法检测动物性水产制品中菌落总数的不确定度分析与评定

同方期刊数据库博看期刊评论

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食品安全导刊 2024年第5期 57-59页

作者：杨蕊银刘胤璇白秀珍李春江红河哈尼族彝族自治州质量技术监督综合检测中心云南蒙自661199

目的:建立测试片法测定菌落总数的不确定度评定方法,在具体检测中提高科学性和准确性。方法:利用统计学方法计算各不确定度分量、合成不确定度及扩展不确定度。结果:在95%置信水平下,测试片法检测动物性水产制品中菌落总数含量对数的扩... 详细信息

目的:建立测试片法测定菌落总数的不确定度评定方法,在具体检测中提高科学性和准确性。方法:利用统计学方法计算各不确定度分量、合成不确定度及扩展不确定度。结果:在95%置信水平下,测试片法检测动物性水产制品中菌落总数含量对数的扩展不确定度为0.2322,结论:测试片法检测动物性水产品中菌落总数中,重复试验对不确定度结果的贡献较大。

关键词：菌落总数测试片菌落总数不确定度评定

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无临设工程施工的沉桩方法及工法设计

中国防汛抗旱 2024年第3期34卷 81-84页

作者：张宝森胡全义李宇鹏李春江邓宇黄河水利委员会黄河水利科学研究院郑州450003 水利部堤防安全与病害防治工程技术研究中心郑州450003 华北水利水电大学郑州450045

传统的打桩(振动、冲击)技术,不仅需要打桩机,还需要施工车辆、大型附带设备及暂设工程,施工效率低、占地面积大,对生态环境影响大。以黄河堤岸刚性加固为需求导向,设计了无临设工程施工的沉桩方法,并开发出整套设备,该设备主要包含静... 详细信息

传统的打桩(振动、冲击)技术,不仅需要打桩机,还需要施工车辆、大型附带设备及暂设工程,施工效率低、占地面积大,对生态环境影响大。以黄河堤岸刚性加固为需求导向,设计了无临设工程施工的沉桩方法,并开发出整套设备,该设备主要包含静压植桩机、动力单元、桩用起吊装置及桩材自走装置。该工法实现了无暂设工程施工,提高了作业效率,减小了对生态的影响。从工法特点、施工周期、施工成本、硬质地层适应性、成桩质量、占地面积和环境影响(CO_(2)排放)等方面对比分析了此方法与传统施工的优缺点。结果表明,该方法可广泛应用于坝决口封堵、堤防加固、植入式斜桩护岸、挡土墙、止水墙、基础和地基工程加固等方面。

关键词：沉桩方法无临设工程施工工法设计

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智能化中药栓剂灌装设备研制与试验

北华大学学报（自然科学版） 2024年第4期25卷 539-544页

作者：曹霖霖李春江周小龙李建永刘华伟王开宝北华大学机械工程学院吉林吉林132021

针对中药制药装备普遍存在的高耗能、低效率、非标准化等问题,研制基于柱塞泵工作原理的中药栓剂自动化灌装设备,以提高栓剂产品质量与生产效率,实现高效灌装。以灌装效率、药膏温度控制、定量精度为指标开展试验。结果表明:研制的智能... 详细信息

针对中药制药装备普遍存在的高耗能、低效率、非标准化等问题,研制基于柱塞泵工作原理的中药栓剂自动化灌装设备,以提高栓剂产品质量与生产效率,实现高效灌装。以灌装效率、药膏温度控制、定量精度为指标开展试验。结果表明:研制的智能化中药栓剂灌装设备能够保证产品质量,实现高效灌装,减少人工,灌注速率可达360支/min,定量误差约为±0.8%。

关键词：中药栓剂智能化灌装设备中药制药装备