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CTDAE & CTODE models and their applications to power system stability analysis with time delays

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Science China(Technological Sciences) 2013年第5期56卷 1213-1223页

作者： yu xiaodan JIA HongJie WANG ChengShan Key Laboratory of Smart Grid of Ministry of Education Tianjin University

In this paper,two new models suitable for power system stability analysis with considering time delays are derived.They are constraint time-delayed ordinary differential equation model(CTODE model) and constraint time-delayed differential algebraic equation model(CTDAE model).In these two models,dimension of the time-delayed equation is significantly reduced so as to speed up the calculation efficiency.Detail derivations to their nonlinear and incremental linear forms are given.And,some of their good features are discussed.Finally,a typical time-delayed system and single-machine-infinite-bus system are selected to validate the new models through Lyapunov-Krasovskii criterion and eigenvalue locus tracing procedure.It reveals that some unnecessary calculations in the algorithm can be avoided to achieve higher efficiency based on new models.The new models and new criterion given in this paper are helpful to design wide area protectors for bulk power systems.

关键词：时间延迟系统电力系统方程模型计算效率 E模型稳定分析微分代数 CTOD

Deficiency of betaine-homocysteine methyltransferase activates glucose-6-phosphate dehydrogenase(G6PD) by decreasing arginine methylation of G6PD in hepatocellular carcinogenesis

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Science China Life Sciences 2024年第8期 1648-1665页

作者： Jie Gao Xiaoyi Shi Yaohui Sun Xudong Liu Feng Zhang Chengcheng Shi Xiao yu Zhiping Yan Long Liu Shizhe yu Jiacheng Zhang xiaodan Zhang Shuijun Zhang Wenzhi Guo Department of Hepatobiliary and Pancreatic Surgery The First Affiliated Hospital of Zhengzhou University Henan Diagnosis & Treatment League for Hepatopathy The First Affiliated Hospital of Zhengzhou University Henan Innovative Research Group for Hepatobiliary & Pancreatic Surgery and Digestive Organ Transplantation Henan Organ Transplantation Quality Control Centre Henan Engineering Technology Research Center for Organ Transplantation Department of Pharmacy The First Affiliated Hospital of Zhengzhou University Department of General Surgery Huashan HospitalFudan University Cancer Metastasis Institute Fudan University

Betaine-homocysteine methyltransferase（BHMT） regulates protein methylation and is correlated with tumorigenesis;however,the effects and regulation of BHMT in hepatocarcinogenesis remain largely unexplored.Here,we determined the clinical significance of BHMT in the occurrence and progression of hepatocellular carcinoma（HCC） using tissue samples from 198 patients.BHMT was to be frequently found（86.6%） expressed at relatively low levels in HCC tissues and was positively correlated with the overall survival of patients with HCC.Bhmt overexpression effectively suppressed several malignant phenotypes in hepatoma cells in vitro and in vivo,whereas complete knockout of Bhmt(Bhmt-/-) produced the opposite effect.We combined proteomics,metabolomics,and molecular biological strategies and detected that Bhmt-/-promoted hepatocarcinogenesis and tumor progression by enhancing the activity of glucose-6-phosphate dehydrogenase（G6PD）and PPP metabolism in DEN-induced HCC mouse and subcutaneous tumor-bearing models.In contrast,restoration of Bhmt with an AAV8-Bhmt injection or pharmacological inhibition of G6PD attenuated hepatocarcinogenesis.Additionally,coimmunoprecipitation identified monomethylated modifications of the G6PD,and BHMT regulated the methylation of G6PD.Protein sequence analysis,generation and application of specific antibodies,and site-directed mutagenesis indicated G6PD methylation at the arginine residue 246.Furthermore,we established bidirectionally regulated BHMT cellular models combined with methylation-deficient G6PD mutants to demonstrate that BHMT potentiated arginine methylation of G6PD,thereby inhibiting G6PD activity,which in turn suppressed hepatocarcinogenesis.Taken together,this study reveals a new methylation-regulatory mechanism in hepatocarcinogenesis owing to BHMT deficiency,suggesting a potential therapeutic strategy for HCC treatment.

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Effective Removal of Tetracycline by Using Biochar Supported Fe3O4 as a UV-Fenton Catalyst

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Chemical Research in Chinese Universities 2019年第1期35卷 79-84页

作者： yu xiaodan LIN Xinchen LI Weiguang FENG Wei School of Environment Harbin Institute of TechnologyHarbin 150090P.R.China Key Labroratory of Songliao Aquatic Environnmento Ministry of Education Jilin Jianzhu UniversityChangchun 130118P.R.China Key Laboratory of Groundwater Resource and Environment Ministry Education College of Environment and ResourcesJilin UniversityChangehun 130021P.R.China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090.P.R.China

Novel Fe3O4-decorate hierarchical porous carbon skeleton derived from maize straw(Fe3O4@MSC)was synthesized by a facile co-precipitation process and a calcination process,which was developed as a UV assisted heterogeneous Fenton-like catalyst.The as-synthesized catalysts were characterized via X-ray powder diffraction(XRD), scanning electron microscope(SEM),transmission electron microscope(TEM),Brunauer-Emmet-Teller(BET)and vibrating sample magnetometer(VSM)at room temperature.The morphology and structure analysis revealed that the as-prepared Fe3O4@MSC retained the original pore morphology of the maize straw material.The non-uniform poly- hedral Fe3O4 grew on the whole surface of the MSC,which reduced the aggragation of Fe3O4 and provided more active sites to strengthen the UV-assisted Fenton-like reaction.As a result,the tetracycline(TC)degradation efficiency after 40 min reaction and total organic carbon(TOC)removal efficiency after 2 h reaction of Fe3O4@MSC catalyzing UV-Fenton system reached 99.2%and 72.1%,respectively,which were more substantial than those of Fe3O4@MSC/H2O2(31.5%and 2%),UV/H2O2 system(68%and 23.4%)and UV/Fe3O4/H2O2(80% and 37.5%).The electron spin resonance(ESR)results showed that the ·OH played an important role in the catalytic reaction.A possible degradation pathway of TC was proposed on the basis of the identified intermediates.Overall,the UV assisted heterogeneous Fenton-like process in Fe3O4@MSC improved the cycle of Fe^3+/Fe^2+ and activated the interfacial catalytic site,which eventually realized the enhancement of degradation and mineralization to tetracycline.

关键词： Fe3O4 Carbon skeleton of maize straw,Heterogeneous Fenton-like catalyst UV irradiation Degradation of tetracycline

The key technology of Micro area visualization in the application of the oil and gas exploration and development

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Acta Geologica Sinica(English Edition) 2015年第A1期89卷 405-408页

作者： SUN Xianda TANG Wenhao yu xiaodan Exploration and Development Research hlstitute of Daqing Oilfield Company Limited Daqing 163318 China Enhanced Oil Recovery Research Institute China University of Petroleum (Beijing) Beijing 102249 China School of Petroleum and NaturalGas Engineering Southwest Petroleum University Chengdu 610500 China

1 Introduction Micro area visualization technology is one of the most reliable and most intuitive technological means for our engineers on solving difficult reservoir problems. This not only can be clearly definite such as Oil and gas occurrence of geological problems in the process of oil and gas exploration, but also can be solved remaining oil distribution and mechanism of exploitation problems in the process of oil and gas development.

关键词： PETROLEUM prospecting OIL reservoir engineering PETROLEUM reservoirs NATURAL gas -- Prospecting COMPUTER visualization

Ultraviolet Light Assisted Hierarchical Porous Fe2O3 Catalyzing Heterogeneous Fenton Degradation of Tetracycline Under Neutral Condition with a Low Requirement of H2O2

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Chemical Research in Chinese Universities 2019年第2期35卷 304-310页

作者： LIN Xinchen XIE Feng yu xiaodan TANG Xin GUAN Heda CHEN yu FENG Wei Key Laboratory of Groundwater Resource and Environment Ministry of EducationCollege of New Energy and EnvironmentJilin UniversityChangchun 130021P.R.China School of Environment Harbin Institute of TechnologyHarbin 150090R R. China

The hierarchical porous Fe2O3 particles as a novel ultraviolet light assisted heterogeneous Fenton catalysts were synthesized by bio-template synthesis method using iron nitrate as precursor at high temperature of around 550℃.The hierarchical porous structured Fe2O3 was endowed with a large surface area and abundant pore volume,leading to the exposure of more active sites and rapid mass transfer.The synergistic effect of UV irradiation and hie-rarchical porous Fe2O3 improved the photo-degradation efficiency of Tetracycline(TC).The degradation efficiency of Fe203 catalyzing UV-Fenton system reached 97.4%after 60 min reaction,which was more substantial than Fe2O3 catalyzing Fenton system(7.6%)and UV/H2O2 system(59.2%).Moreover,the hierarchical porous Fe2O3 catalyzing UV-Fenton system exhibited an extremely wide pH range(from 3.0 to 9.0,from mildly acidic to slightly alkaline)for efficient degradation of TC.Simultaneously,the extraordinary higher degradation efficiency was based on 10 mmol/L H2O2 concentration,which was low requirement for H2O2,Further,the hierarchical porous Fe2O3 can be used for five consecutive cycles with over 95%of the original degradation efficiency.Ultraviolet light assisted heterogeneous Fenton reaction in the hierarchical porous Fe2O3 improved the·OH and O2·^-production and Fe(III)/Fe(II)redox cycle,which consequently achieved an excellent degradation rate.

关键词： Heterogeneous Fenton Hierarchical porous Fe2O3 Biological template method Tetracycline degradation

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建筑设计装饰公司的视觉形象设计

鞋类工艺与设计 2024年第4期4卷 60-62页

作者：于晓丹广州工商学院广东广州510000

现代社会经济的不断发展,不同类别的公司如雨后春笋般不断涌现。为了在同行业中脱颖而出,公司不仅需要提升产品和服务的质量,更需要建立良好的品牌形象。其中,企业的品牌视觉形象是整个形象建立中最重要一环。企业可以通过统一的视觉形... 详细信息

现代社会经济的不断发展,不同类别的公司如雨后春笋般不断涌现。为了在同行业中脱颖而出,公司不仅需要提升产品和服务的质量,更需要建立良好的品牌形象。其中,企业的品牌视觉形象是整个形象建立中最重要一环。企业可以通过统一的视觉形象设计,形成一定的品牌印象,从而更好地提升整个企业的品牌特征,促进自身的发展。本研究将结合建筑装饰设计公司进行视觉形象的设计,内容包括一整套的Ⅵ设计,并形成统一的简约风格,以期为今后的视觉形象设计案例提供一些设计灵感与借鉴。

关键词：建筑装饰设计公司视觉形象设计企业形象

文化保护与乡村振兴协同的杨家沟建设规划研究

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西安建筑科技大学学报（自然科学版） 2024年第3期56卷 358-365页

作者：杨晓丹白钰周庆华西安建筑科技大学中国城乡建设与文化传承研究院陕西西安710055 陕西省哲学社会科学重点研究基地(城乡历史文化传承研究基地) 陕西西安710055 中国电建集团西北勘测设计研究院陕西西安710055 西安建筑科技大学建筑学院陕西西安710055

以杨家沟为代表的一类特殊乡村具有红色文化资源丰富但地处偏远、对外交通不便、产业基础薄弱、土地资源紧缺等特征,长期面临红色文化资源保护与乡村振兴的双重压力.基于乡村地域系统理论与评估框架,诊断杨家沟乡村子系统发展水平及问题... 详细信息

以杨家沟为代表的一类特殊乡村具有红色文化资源丰富但地处偏远、对外交通不便、产业基础薄弱、土地资源紧缺等特征,长期面临红色文化资源保护与乡村振兴的双重压力.基于乡村地域系统理论与评估框架,诊断杨家沟乡村子系统发展水平及问题,结果表明:杨家沟乡村子系统呈两极化发展水平,虽然红色文化资源丰富、历史文化底蕴深厚,但在生态环境脆弱、土地资源紧缺、遗产保护要求约束的影响下,该村农业和旅游业难以充分发展,导致人口外流、产业空心化、经济发展缓慢,进一步加剧遗址维护人员及资金短缺、遗址保护管理不善等问题.对此,规划提出“红色文化+X”的发展模式,形成文化遗产带动红色旅游、红色旅游反哺遗产保护、促进乡村振兴的良性循环,并采用“枝状网络分形”的空间布局,解决遗址环境保护与旅游产业发展、移民搬迁安置的潜在用地冲突.

关键词：乡村振兴红色文化保护乡村地域系统分形黄土高原

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线上线下融合的诊疗努力分配决策研究

管理评论 2024年第3期36卷 210-224页

作者：吴晓丹杨悦张晓亚俞天智河北工业大学经济管理学院天津300401 天津医科大学总医院天津300052

线上线下融合成为保障医疗服务连续性,提升服务质量,降低患者再入院率的有效措施。基于医疗服务提供者(healthcare provider,HCP)难以平衡线上线下服务间有限诊疗资源分配的现状,本文针对诊疗后期将病人由线下转至线上的行为,建立按服... 详细信息

线上线下融合成为保障医疗服务连续性,提升服务质量,降低患者再入院率的有效措施。基于医疗服务提供者(healthcare provider,HCP)难以平衡线上线下服务间有限诊疗资源分配的现状,本文针对诊疗后期将病人由线下转至线上的行为,建立按服务项目付费(fee-for-service,FFS)、预付制(prospective payment system,PPS)、捆绑支付(bundled payment,BP)和按绩效付费(pay-for-performance,P4P)四种支付方式下HCP与政府间博弈模型,研究激励HCP合理分配线上线下诊疗资源的医保支付方式。研究结果表明:FFS难以激励HCP在线上护理治疗阶段付出努力;PPS和BP虽然能诱导一定程度的线上诊疗努力,但始终无法协调至社会最优,增加支付金额也并不一定能够提高线上努力水平;基于P4P的再入院减少计划(hospital readmission reduction program,HRRP)下加大处罚力度不一定是最优选择,也并不总能将线上诊疗努力水平协调至社会最优;最后,本文提出取消HRRP罚款上限并设置奖励规则的混合支付方式可以弥补HRRP不足,并有效协调线上诊疗努力水平至社会最优。

关键词：线上线下融合努力水平医保支付惩罚规则

改进下垂控制下的中压直流配电系统双时间尺度分层调控方法

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中国电机工程学报 2024年第7期44卷 2507-2518,I0001页

作者：肖迁陆文标贾宏杰穆云飞余晓丹智能电网教育部重点实验室(天津大学) 天津市南开区300072

针对中压直流配电系统,在负荷激增、可再生能源出力突变等特殊工况下,传统优化调度方案与协调控制策略存在系统运行经济性有待提升、直流母线电压易越限的问题。为此,提出一种基于改进下垂控制的中压直流配电系统双时间尺度分层调控方... 详细信息

针对中压直流配电系统,在负荷激增、可再生能源出力突变等特殊工况下,传统优化调度方案与协调控制策略存在系统运行经济性有待提升、直流母线电压易越限的问题。为此,提出一种基于改进下垂控制的中压直流配电系统双时间尺度分层调控方法。首先,构建一种具备直流故障穿越能力的3端混合型模块化多电平换流器(modular multilevel converter,MMC)环状±10 kV中压直流配电系统,该系统含电动汽车充电站、储能系统、分布式光伏与风电等灵活性资源。其次,制定各单元协调控制策略,并采用tan函数改进传统下垂控制,以提高系统应对大幅功率波动的能力。然后,基于改进控制策略提出一种双时间尺度分层优化调控方法:在长时间尺度的系统调度层,以运行总成本最小为优化目标,确定各换流器参考功率;在短时间尺度的换流器间协调控制层,改进下垂曲线,并优化控制系数,以兼顾系统运行经济性与电能质量。最后,以典型算例验证该文所提优化调度方案及协调控制策略的有效性:通过灵活调度多种柔性资源,系统运行总成本可降低约11%;在某数据中心负荷激增100%的工况下,各直流母线电压波动仍能维持在±3%UN(额定电压)的允许范围内。

关键词：中压直流配电系统分层协调控制双时间尺度优化改进下垂控制系数优化