检索结果-南通市图书馆

同方期刊数据库

电商背景下考虑参考价格效应的低碳产品制造商入侵研究

在线全文

学校读者我要写书评

暂无评论

物流工程与管理 2024年第6期46卷 42-46页

作者：黄建平武汉科技大学管理学院湖北武汉430081

构建由低碳产品制造商作为领导者、零售商作为追随者组成的Stackelberg博弈模型,制造商可能通过电商渠道入侵市场,而消费者会对比不同渠道价格,即受到参考价格效应的影响。研究发现:(1)当制造商入侵市场时,参考价格系数和低碳敏感度的... 详细信息

构建由低碳产品制造商作为领导者、零售商作为追随者组成的Stackelberg博弈模型,制造商可能通过电商渠道入侵市场,而消费者会对比不同渠道价格,即受到参考价格效应的影响。研究发现:(1)当制造商入侵市场时,参考价格系数和低碳敏感度的增加都会使得制造商提高碳减排努力程度,同时电商渠道和线下渠道的销售数量将提高。(2)只有当低碳敏感性系数较高时,制造商和零售商才能够就制造商的入侵行为达成共赢,且这种共赢的可能性随消费者对线下渠道忠诚度的提高而增加(尽管消费者对线下渠道忠诚度的增加会降低制造商入侵的意愿)。(3)入侵行为总会增加制造商的生产量,即能促进低碳产品的消费。

关键词：制造商入侵参考价格效应低碳努力供应链管理

在线全文

学校读者我要写书评

暂无评论

沙尘气溶胶加热对深积云对流系统的影响

兰州大学学报（自然科学版） 2024年第3期60卷 296-303页

作者：景治坤黄建平刘玉芝谢永坤兰州大学半干旱气候变化教育部重点实验室西部生态安全省部共建协同创新中心兰州730000

基于动力模型,分析在水汽充足的深对流天气系统中沙尘气溶胶的加热作用及其对周围大气稳定性、积云对流及降水的影响.结果表明,沙尘气溶胶可在550 hPa对流层中层被输送至水汽充足的深积云对流系统中,其加热效应使大气温度升高,增强对流... 详细信息

基于动力模型,分析在水汽充足的深对流天气系统中沙尘气溶胶的加热作用及其对周围大气稳定性、积云对流及降水的影响.结果表明,沙尘气溶胶可在550 hPa对流层中层被输送至水汽充足的深积云对流系统中,其加热效应使大气温度升高,增强对流扰动的进一步发展,使得大气稳定性减弱,促进积云对流发展及其潜热释放;积云对流引起的对流加热与涡度混合,进一步增强垂直运动和积云对流发展;这种正反馈效应使整个深积云对流系统变得更加不稳定.正反馈强度随着扰动水平尺度的减小而增强,涡度混合引起的强垂直运动可将积云中的沙尘由低层向高层输送.当沙尘同时存在于550和950 hPa两个高度时,上、下两层的加热作用可共同加速深积云对流系统的不稳定化过程,其中上层沙尘的作用更显著.

关键词：沙尘气溶胶深积云对流加热作用不稳定增长率正反馈

基于改进boxlevelset的叶片显微图像气孔分割方法

在线全文

学校读者我要写书评

暂无评论

电脑与信息技术 2024年第2期32卷 33-35,70页

作者：郑禹曦黄建平东北林业大学计算机与控制学院黑龙江哈尔滨150040

深度学习技术已被用于气孔分割任务。然而,训练数据的标注是机械且耗时的人工过程,特别是在数据集比较大的时候。为了减少标注时的工作量,研究提出一种基于弱监督模型Boxlevelset的气孔分割方法。将原模型的特征提取网络ResNet50替换为R... 详细信息

深度学习技术已被用于气孔分割任务。然而,训练数据的标注是机械且耗时的人工过程,特别是在数据集比较大的时候。为了减少标注时的工作量,研究提出一种基于弱监督模型Boxlevelset的气孔分割方法。将原模型的特征提取网络ResNet50替换为ResNest50,并且在特征提取过程中引入CBAM模块。以黑杨气孔为研究对象,该方法可有效分割出气孔,F1得分为79.89。所提出的方法减少了标注训练数据所需的时间,同时保证了分割精度,从而显著减少了训练气孔分割网络所需的工作量。

关键词：叶片气孔分割神经网络弱监督注意力机制

2021年“7·20”河南特大暴雨水汽输送特征

在线全文

学校读者我要写书评

暂无评论

兰州大学学报（自然科学版） 2024年第2期60卷 143-150页

作者：闫玮欧阳智王泳棋黄建平赵庆云兰州大学大气科学学院兰州730000 兰州大学西部生态安全省部共建协同创新中心兰州730000

2021年7月20日河南郑州出现极端暴雨,降水量达624.1 mm,最大小时降水量201.9 mm,突破中国内地小时降水量历史极值.利用常规气象观测资料、再分析资料以及基于拉格朗日方法的水汽轨迹追踪模式,分析暴雨的水汽输送情况.结果表明,大尺度环... 详细信息

2021年7月20日河南郑州出现极端暴雨,降水量达624.1 mm,最大小时降水量201.9 mm,突破中国内地小时降水量历史极值.利用常规气象观测资料、再分析资料以及基于拉格朗日方法的水汽轨迹追踪模式,分析暴雨的水汽输送情况.结果表明,大尺度环流异常形成的持续偏东风和南风的水汽输送,导致河南大范围持续暴雨;持续存在的低涡是降水长时间持续的原因,同时高、低空环流系统配置,为暴雨发展提供有利条件;20日郑州南边界水汽输送的急剧增加,是造成极端暴雨的关键;暴雨水汽输送通道主要有700 hPa高度上来自南海的水汽贡献(61.0%)和太平洋通道(33.0%);850 hPa,来自太平洋的水汽贡献达82.3%,来自南海水汽贡献为17.7%.

关键词：极端暴雨水汽输送水汽收支拉格朗日方法

原花青素下调wnt/β-catenin通路拮抗砷诱导的人肝细胞L-02增殖

在线全文

学校读者我要写书评

暂无评论

现代预防医学 2024年第8期51卷 1486-1492+1529页

作者：任庆新张卫兵黄建萍安娜柴婧南通市疾病预防控制中心乌鲁木齐市疾病预防控制中心

目的本次研究使用原花青素（Proanthocyanidins, PC）和亚砷酸钠（Sodium arsenite, NaAsO2）对人肝细胞L-02进行干预，探究砷致细胞增殖的效应，PC对砷作用的拮抗以及与wnt/β-catenin信号通路的关系。方法以不同剂量的PC单独或与NaA... 详细信息

目的本次研究使用原花青素（Proanthocyanidins, PC）和亚砷酸钠（Sodium arsenite, NaAsO2）对人肝细胞L-02进行干预，探究砷致细胞增殖的效应，PC对砷作用的拮抗以及与wnt/β-catenin信号通路的关系。方法以不同剂量的PC单独或与NaAsO2联合干预细胞，利用细胞计数试剂盒-8（Cell Counting Kit-8, CCK-8）法检测细胞增殖活力，使用细胞划痕实验、Transwell实验检测细胞的迁移和侵袭能力，使用实时聚合酶链反应（Real-time Polymerase Chain Reaction, Real-time PCR）法和免疫印迹（Western Blotting, WB）法检测相关因子的信使RNA（message RNA, mRNA）和蛋白表达水平。结果 NaAsO2致细胞增殖活性（1.740±0.105）升高，迁移（556.000±3.606）、侵袭（439.667±8.622）能力增强，上调原癌基因c-myc（0.739±0.012）、细胞周期蛋白D1（cyclinD1）(0.943±0.002)、血管内皮生长因子（Vascular endothelial growth factor, VEGF）(1.020±0.019)、凋亡抑制基因survivin（0.571±0.033）和基质金属蛋白酶-7（Matrix metalloproteinase-7, MMP-7）(0.695±0.059)的蛋白表达水平，上调wnt3a和β-连环蛋白（β-catenin）的蛋白（分别为1.044±0.010, 0.958±0.037）和mRNA（分别为1.789±0.165, 1.596±0.217）水平。当PC与NaAsO2联合处理后，相较于NaAsO2单独干预，c-myc（0.438±0.046）等增殖相关蛋白及信号通路核心分子wnt3a（0.822±0.015）、β-catenin（0.832±0.064）表达水平下降，通路抑制因子糖原合成酶激酶-3β（Glycogen synthase kinase-3β, GSK-3β）(0.885±0.058)和轴蛋白（Axin）(0.749±0.016)表达升高。结论 NaAsO2诱导L-02细胞增殖，这可能是由其激活了wnt/β-catenin信号通路导致的；PC可以下调wnt/β-catenin通路，进而拮抗NaAsO2所致的细胞增殖。

关键词：砷原花青素增殖 wnt/β-catenin信号通路

Thermal Expansion Coefficients of Thin Crystal Films

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2005年第5X期44卷 921-924页

作者： huang jian-ping WU Xue-Zhong LI Sheng-Yi Mechatronics Engineering Institute National University of Defense Science and Technology Changsha 410073 China

The formulas for atomic displacements and Hamiltonian of a thin crystal film in phonon occupation number representation are obtained with the aid of Green's function theory. On the basis of these results, the formulas for thermal expansion coefficients of the thin crystal film are derived with the perturbation theory, and the numerical calculations are carried out. The results show that the thinner films have larger thermal expansion coefficients.

关键词： thermal expansion coefficients thin crystal film Green's function perturbation theory

ShRNA-mediated gene silencing of β-catenin inhibits growth of human colon cancer cells

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第48期13卷 6581-6587页

作者： Wen-Sheng huang jian-ping Wang Ting Wang Jie-Yu Fang ping Lan Jin-ping Ma Surgery Department The First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 Guangdong Province China

AIM: To observe the gene silencing mediated by the specific shRNA targeted against β-catenin and its effect on cell proliferation and cycle distribution in the human colon cancer cell line Colo205. METHODS: Two shRNA plasmid vectors against β-catenin were constructed and transfected into Colo205 cells with LipofectamineTM2000. The down-regulations of β-catenin, c-myc and cyclinD1 expressions were detected by RT-PCR and western blot analysis. The cell proliferation inhibitions were determined by MTT assay and soft agar colony formation assay. The effect of these two β-catenin shRNAs on cell cycle distribution and apoptosis was examined by flow cytometry. RESULTS: These two shRNA vectors targeted against β-catenin efficiently suppressed the expression of β-catenin and its down stream genes, c-myc and cyclinD1. The expression inhibition rates were around 40%-50% either at the mRNA or at the protein level. The shRNA-mediated gene silencing of β-catenin resulted in significant inhibition of cell growth both on the culture plates and in the soft agar. Moreover, the cancer cells showed significant G0/G1 arrest and increased apoptosis at 72 h post transfection due to gene silencing. CONCLUSION: These specific shRNAs targeted against β-catenin could have a gene silencing effect and block the WNT signaling pathway. They could inhibit cell growth, increase apoptosis, and induce cell cycle arrest in Colo205 cells. ShRNA interference against β-catenin is of potential value in gene therapy of colon cancer.

关键词： β-catenin RNA interference Apoptosis Colon cancer WNT

Prevention of Osteopenia and Dyslipidemia in Rats after Ovariectomy with Combined Aspirin and Low-dose Diethylstilbestrol

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2013年第4期26卷 249-257页

作者： LIN Si En huang jian ping WU Ling Zhi WU Tie CUI Liao Department of Pharmacology Guangdong Medical College Department of Stomatology Guangdong Medical College Guangdong Key Laboratory for Research and Development of Natural Drugs

Objective To study whether effect of aspirin plus low-dose diethylstilbestrol is more effective and safer than high diethylstilbestrol dose alone on prevention of ovariectomy-induced osteopenia and dyslipidemia. Methods Thirty-eight 4-month-old female SD rats were divided into baseline （BAS） group （n=6）, sham operation group （n=8） and ovariectomy （OVX） group （n=24）. The OVX group was further divided into vehicle treatment group （n=8）, diethylstilbestrol （30 ug/kg.d） treatment group （OVX＋D30 group, n=8）, and aspirin （9 mg/kg.d） plus diethylstilbestrol （10 ug/kg.d） treatment group （OVX＋A-D10 group, n=8）. Their left tibiae were collected for the bone histomorphometric analysis in undecalcified sections. Left femurs were collected for the bone mineral density measurement. Results The body weight and serum cholesterol were increased, while uterine weight and cancellous bone mass were decreased in OVX rats compared with the SHAM group. Cancellous bone mass was significantly increased, while body weight and bone resorption parameters were decreased in both A-D10 and D30 treatment group compared with OVX group. The rats treated with A-D10 showed significantly increased in bone formation parameters and decreased in serum triglyceride compared with the D30-treated rats. Conclusion Aspirin plus low-dose diethylstilbestrol can effectively prevent osteopenia by reducing bone resorption, and is thus a better treatment modality for preventing dyslipidemia than high-dose diethylstilbestrol alone.

关键词： Aspirin Diethylstilbestrol Ovariectomy Osteoporosis Dyslipidemia Rat

Wavefield reconstruction inversion with weaktotal-variation constraint based on first arrival traveltime tomography

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2022年第2期19卷 232-243,308页

作者： Zhang Shao-Shun huang jian-ping Wang Zhen-Yu School of Geosciences China University of PetroleumQingdao 266580China Sinopec Petroleum Exploration and Production Research Institute Beijing 100083China

The objective function of full waveform inversion is a strong nonlinear function,the inversion process is not unique,and it is easy to fall into local ***,in the process of wavefield reconstruction,the wave equation is introduced into the construction of objective function as a penalty term to broaden the search space of solution and reduce the risk of falling into local *** addition,there is no need to calculate the adjoint wavefield in the inversion process,which can significantly improve the calculation efficiency;Secondly,considering that the total variation constraint can effectively reconstruct the discontinuous interface in the velocity model,this paper introduces the weak total variation constraint to avoid the excessive smooth estimation of the model under the strong total variation *** disadvantage of this strategy is that it is highly dependent on the initial *** view of this,this paper takes the long wavelength initial model obtained by first arrival traveltime tomography as a prior model constraint,and proposes a weak total variation constrained wavefield reconstruction inversion method based on first arrival traveltime *** experimental results show that the new method reduces the dependence on the initial model,the interface description is more accurate,the error is reduced,and the iterative convergence efficiency is significantly improved.

关键词： Full waveform inversion wavefield reconstruction inversion total variation constraint weak total variation constraint first arrival traveltime tomography