Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks worldwide.This study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation processes.Integrating with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay Basin.The oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual hydrocarbons.Compared with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and cutinite.And part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil yield.The results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was lower than SOGP peak oil yield.There were significant differences in saturated hydrocarbon and aromatic parameters in coal and coaly shale.Coal SOGP was characterized by a lower Ts/Tm and C31-homohopane22S/(22S+22R)and a higher Pr/n C17compared to coal TOGP,while the aromatic parameter methyl dibenzothiophene ratio(MDR)exhibited coaly shale TOGP was higher than coaly shale SOGP than coaly TOGP than coaly SOGP,and coal trimethylnaphthalene ratio(TNR)was lower than coaly shale TNR.Thus,we established oil generation processes and discriminative plates.In this way,we distinguished the differences between oil generation parent maceral,oil generation time,and oil production of coaly source rocks,and therefore,we provided important support for the evaluation,prediction,and exploration of oil resources from global ancient coaly source rocks.

Multi-Time Scale Optimal Scheduling of a Photovoltaic Energy Storage Building System Based on Model Predictive Control

Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance.

Low-carbon generation expansion planning considering uncertainty of renewable energy at multi-time scales

With the development of carbon electricity,achieving a low-carbon economy has become a prevailing and inevitable trend.Improving low-carbon expansion generation planning is critical for carbon emission mitigation and a lowcarbon economy.In this paper,a two-layer low-carbon expansion generation planning approach considering the uncertainty of renewable energy at multiple time scales is proposed.First,renewable energy sequences considering the uncertainty in multiple time scales are generated based on the Copula function and the probability distribution of renewable energy.Second,a two-layer generation planning model considering carbon trading and carbon capture technology is established.Specifically,the upper layer model optimizes the investment decision considering the uncertainty at a monthly scale,and the lower layer one optimizes the scheduling considering the peak shaving at an hourly scale and the flexibility at a 15-minute scale.Finally,the results of different influence factors on low-carbon generation expansion planning are compared in a provincial power grid,which demonstrate the effectiveness of the proposed model.

Bio-Inspired Optimal Dispatching of Wind Power Consumption Considering Multi-Time Scale Demand Response and High-Energy Load Participation

Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this paper constructs a bio-inspired computer model.It is an optimal wind power consumption dispatching model of multi-time scale demand response that takes into account the involved high-energy load.First,the principle of wind power obstruction with the involvement of a high-energy load is examined in this work.In this step,highenergy load model with different regulation characteristics is established.Then,considering the multi-time scale characteristics of high-energy load and other demand-side resources response speed,a multi-time scale model of coordination optimization is built.An improved bio-inspired model incorporating particle swarm optimization is applied to minimize system operation and wind curtailment costs,as well as to find the most optimal energy configurationwithin the system.Lastly,we take an example of regional power grid in Gansu Province for simulation analysis.Results demonstrate that the suggested scheduling strategy can significantly enhance the wind power consumption level and minimize the system’s operational cost.

Multi-time scale analysis of precipitation variation in Guyuan, China:1957-2005

Morlet wavelet transformation is used in this paper to analyze the multi time scale characteristics of pre cipitation data series from 1957 to 2005 in Guyuan region.The results showed that(1) the annual precipitation evo lution process had obvious multi time scale variation characteristics of 15 25 years,7 12 years and 3 6 years,and different time scales had different oscillation energy densities;(2) the periods at smaller time scales changed more frequently,which often nested in a biggish quasi periodic oscillations,so the concrete time domain should be ana lyzed if necessary;(3) the precipitation had three main periods(22 year,9 year and 4 year) and the 22 year period was especially outstanding,and the analysis of this main period reveals that the precipitation would be in a relative high water period until about 2012.

Market-based control strategy for long-span structures considering the multi-time delay issue

To solve the different time delays that exist in the control device installed on spatial structures, in this study, discrete analysis using a 2N precise algorithm was selected to solve the multi-time-delay issue for long-span structures based on the market-based control （MBC） method. The concept of interval mixed energy was introduced from computational structural mechanics and optimal control research areas, and it translates the design of the MBC multi-time-delay controller into a solution for the segment matrix. This approach transforms the serial algorithm in time to parallel computing in space, greatly improving the solving efficiency and numerical stability. The designed controller is able to consider the issue of time delay with a linear controlling force combination and is especially effective for large time-delay conditions. A numerical example of a long-span structure was selected to demonstrate the effectiveness of the presented controller, and the time delay was found to have a significant impact on the results.

Research on multi-time scale doubly-fed wind turbine test system based on FPGA+CPU heterogeneous calculation

As the proportion of renewable energy increases, the interaction between renewable energy devices and the grid continues to enhance. Therefore, the renewable energy dynamic test in a power system has become more and more important. Traditional dynamic simulation systems and digital-analog hybrid simulation systems are difficult to compromise on the economy, flexibility and accuracy. A multi-time scale test system of doubly fed induction generator based on FPGA+ CPU heterogeneous calculation is proposed in this paper. The proposed test system is based on the ADPSS simulation platform. The power circuit part of the test system is setup up using the EMT(electromagnetic transient simulation) simulation, and the control part uses the actual physical devices. In order to realize the close-loop testing for the physical devices, the power circuit must be simulated in real-time. This paper proposes a multi-time scale simulation algorithm, in which the decoupling component divides the power circuit into a large time scale system and a small time scale system in order to reduce computing effort. This paper also proposes the FPGA+CPU heterogeneous computing architecture for implementing this multitime scale simulation. In FPGA, there is a complete small time-scale EMT engine, which support the flexibly circuit modeling with any topology. Finally, the test system is connected to an DFIG controller based on Labview to verify the feasibility of the test system.

“营改增”对高技术服务业企业投资的影响--基于准自然实验的证据

以中国A股市场高技术服务业企业2009—2016的数据为样本,本文采用多时点DID探究“营改增”这一准自然实验对高技术服务企业投资水平的影响。研究表明,“营改增”的实施对高技术服务企业投资水平具有显著的正向促进效应,这一结论经过PSM-DID以及更换被解释变量的稳健性检验后依然成立。研究结论证实了“营改增”的落地可以激励高技术服务企业投资水平的提升,为后续深入推进税收优惠改革提供了一定的参考。

科技金融政策何以影响科技产业集聚发展?

基于2004—2019年288个城市数据,利用多期DID方法评估了促进科技和金融结合试点政策的科技产业集聚发展效应。研究发现:试点政策通过促进试点地区科技人才、科技企业集聚提升了科技产业集聚度,且表现为渐进的动态积累过程;通过安慰剂、PSM-DID、其他稳健DID估计等方法的检验结果均表明试点政策的科技产业集聚效应是稳健的;试点政策主要通过公共、市场科技金融及其交互机制提升科技产业集聚度,具体表现为,试点政策利用公共科技金融引导市场科技金融,发挥信号传递-资源配置效应、风险分担-融资拓展效应、科技成果转化-创新市场化效应,形成资金、人才与企业的良性互动,实现科技产业集聚发展;试点政策存在明显的发展水平、创新能力异质性,在发展水平高、创新能力强的地区产业集聚效应更显著。由此提出优化科技金融政策引导科技产业集聚稳健发展、有机协调发展的对策建议。

跨境电商综合试验区政策对企业创新影响研究

创新是中国经济进入新发展阶段仍保持活力和蓬勃增长势头的关键,而以跨境电商综合试验区政策为代表的制度改革是中国改革开放以来促进创新的法宝。本文基于2011~2020年上市公司的专利申请数据,采用多时点DID的方法研究了跨境电商综合试验区政策对企业创新的影响。研究发现,跨境电商综合试验区政策通过竞争加剧引发的盈利能力下降和技术依赖引致的创新挤出效应对企业创新产生负向影响,且对东部地区企业、国有企业、第三产业企业、规模较大企业创新和策略性创新的负向影响更明显,该政策并不能自动发挥出推动企业创新的作用。为此,本文提出了积极谋求跨境电商发展与企业创新增长双效合并的政策主张。

国家重点实验室与企业“卡脖子”技术创新——基于沪深A股上市公司的证据

“卡脖子”技术对保障国家经济安全、产业安全和国防安全具有战略意义。为探究国家重点实验室对企业“卡脖子”技术创新的影响,文章以2000—2019年我国A股上市公司为样本,采用多时点双重差分模型,探讨国家重点实验室设立对企业“卡脖子”技术创新的影响及机制。研究发现:企业设立国家重点实验室能够显著提升企业“卡脖子”技术创新;内在机理分析表明,企业国家重点实验室的设立通过吸引人才资源、加大研发投入促进企业“卡脖子”技术创新;企业所有权性质正向调节创新意愿对实验室与企业“卡脖子”技术创新之间的关系,即存在联合调节效应;政策异质性检验发现,当企业主管单位为国资委、市场竞争程度较高或企业位于东部地区时,实验室的创新效应较强。文章检验了企业国家重点实验室设立的政策效果和机制,为实验室的优化设计提供实践启示。

“新农合”健康绩效及其作用机制研究——基于CLHLS数据

为考察新农合健康绩效及其作用机制,本文将农村65岁及以上老人作为研究对象,利用CLHLS于2005、2008、2011年的追踪调查数据,运用倾向得分匹配法得到匹配样本,建立多阶段倍差模型,对新农合的健康绩效进行动态追踪分析,并进一步分析新农合对健康的影响途径,研究发现:新农合有利于客观健康的发展,但降低主观健康评价;新农合通过提高医疗服务利用率途径改善老人健康,但整体作用逐年下降。

“人才特区”政策对房价的影响研究

依据2005—2019年全国284个地级市的面板数据,运用多时点双重差分模型,考量“人才特区”政策对房价的影响。结果显示,“人才特区”政策通过提高房价预期与促进产业结构升级间接作用于房价,推动房价上涨。相较于中西部地区与非大中城市,“人才特区”政策对东部地区与大中城市房价的促进作用更显著。鉴于此,应理性制定“人才特区”政策,完善住房保障体系,优化人才发展环境。

高铁开通促进了沿线城镇经济活动吗--来自双源夜间灯光证据

高铁已经成为我国客流主要的运输方式,高铁开通对沿线城镇经济活动带来重要影响。本文基于2008—2017年双源夜间灯光数据集,以沪昆高铁为实证研究对象,在县域尺度下运用多时点DID模型,定量化地探究了高铁开通运营对周边城镇经济活动的影响。研究结果表明:(1)沪昆高铁开通运营对沿线城镇的人口密度、固定资产投资等社会经济活动指标具有正向促进作用,且城镇夜间灯光值与旅行时间距离呈现正"U"型关系;(2)高铁运营对所在城镇的促进作用最大,对18~64分钟时间距离段内的城镇造成虹吸效应,削弱邻近城镇的经济增长;同时会对64~151分钟距离段的城镇经济活动产生促进影响,该影响随着距离的增加,促进效果逐渐减弱。直到在151分钟后,促进效果消失。为更充分发挥沪昆高铁带来的经济发展契机,完善产业布局,促进基础交通建设和产业、城乡融合发展,应建立综合立体的城市交通网,缩短边缘区与核心区的时间距离。中心城镇应扩大经济辐射范围,减少经济分割,与中小城镇协同发展。

Analysis of Changes in Precipitation and Temperature over the Past 60 Years in East China

Based on the mean monthly temperature and precipitation data of East China from 1951 to 2006,we conducted the analysis.The results showed that the mean annual temperature tended to increase in the past 56 years while the variation trend of monthly average temperature was different from the annual one.The obvious increase in temperature happened in early spring and from late autumn to winter.The decrease in temperature happened in summer(August).The precipitation change was not as remarkable as the change in temperature.On the whole,the phase of precipitation change was slightly ahead of temperature change.Continuous wavelet transformation was used to analyze the time-frequency changes of precipitation and temperature in East China and the periodical vibration at different times was obtained.

Study on the Improvement of the Application of Complete Ensemble Empirical Mode Decomposition with Adaptive Noise in Hydrology Based on RBFNN Data Extension Technology

The complex nonlinear and non-stationary features exhibited in hydrologic sequences make hydrological analysis and forecasting difficult.Currently,some hydrologists employ the complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)method,a new time-frequency analysis method based on the empirical mode decomposition(EMD)algorithm,to decompose non-stationary raw data in order to obtain relatively stationary components for further study.However,the endpoint effect in CEEMDAN is often neglected,which can lead to decomposition errors that reduce the accuracy of the research results.In this study,we processed an original runoff sequence using the radial basis function neural network(RBFNN)technique to obtain the extension sequence before utilizing CEEMDAN decomposition.Then,we compared the decomposition results of the original sequence,RBFNN extension sequence,and standard sequence to investigate the influence of the endpoint effect and RBFNN extension on the CEEMDAN method.The results indicated that the RBFNN extension technique effectively reduced the error of medium and low frequency components caused by the endpoint effect.At both ends of the components,the extension sequence more accurately reflected the true fluctuation characteristics and variation trends.These advances are of great significance to the subsequent study of hydrology.Therefore,the CEEMDAN method,combined with an appropriate extension of the original runoff series,can more precisely determine multi-time scale characteristics,and provide a credible basis for the analysis of hydrologic time series and hydrological forecasting.

A Multi-time Scale Tie-line Energy and Reserve Allocation Model Considering Wind Power Uncertainties for Multi-area Systems

Continued expansion of the power grid and the increasing proportion of wind power centralized integration leads to requirements in sharing both energy and reserves among multiple areas under a hierarchical control structure,which successively requires a correction between schedule plans within multi-time scale.In order to address this problem,this paper develops an information integration method integrating complicated relationships among fuel cost,total thermal power output,reserve capacity,owned reserves and expectations of load shedding and wind curtailment,into three types of time-related relationship curves・Furthermore,a multi-time scale tieline energy and reserves allocation model is proposed,which contains two levels in the control structure,two time scales in dispatch sequence and multiple areas integrated within wind farms as scheduling objects・The efficiency of the proposed method is tested in a 9-bus test system and IEEE 118-bus system.The results show that a cross-regional control center is able to approach the optimal scheduling results of the whole system with the integrated uploaded relationship curves.The proposed model not only relieves energy and reserve shortages in partial areas but also allocates them to more urgent need areas in a high effectivity manner in both day-ahead and intraday time scales.

政府研发资助方式对企业创新能力的影响研究

直接资助和税收优惠是政府促进企业创新的主要方式。既有研究聚焦于资助力度与效果分析,鲜有考虑资助方式对多重异质性企业创新能力影响及国家相关政策的调节效应。利用中国A股上市企业数据,根据关键词搜索法和有效平均税率测度法区分直接资助与税收优惠两种方式,借助PSM模型比较分析不同政府研发资助方式对企业创新能力的影响,并从企业多重异质性视角进行验证,之后运用PSM+多时点DID模型考察国家创新型城市试点政策对政府研发资助效果的调节效应。结果显示:整体而言,政府研发资助组合方式对企业创新能力激励效应优于税收优惠或直接资助单一方式;直接资助、税收优惠、政府研发资助组合方式分别对大型国有高技术企业、大型非国有非高技术企业、小型非国有非高技术企业创新能力提升激励效应明显;国家创新型城市试点政策对税收优惠方式挤入效应较明显,而对其他资助方式挤出效应明显。因此,应从运用政府研发资助组合方式、强化资助方式的针对性和倾向性、完善监管审核机制等方面改善政府研发资助方式对企业创新能力提升的应有激励效应。

农地经营权抵押贷款政策对农户增收效应的影响研究——基于多时点DID的实证

全面推进乡村振兴要求把增加农民收入作为中心任务,而农地经营权抵押贷款增加了农户财产处置决策的选择。采用2011—2020年我国30个省区市的面板数据,利用多时点DID方法实证研究发现,农地经营权抵押贷款政策能够提升农户收入,相关法律颁布后影响更为明显,通过了平行趋势、安慰剂等稳健性检验,且农地经营权抵押贷款政策颁布较早地区农户的政策增收效应更为明显。从影响机制看,农地经营权抵押贷款政策通过投资水平、信贷水平和非农就业水平的中介机制,促进了农户增收,缩小了农户之间的收入差距,有助于实现农村共同富裕。从农户异质性结果看,教育培训多的农户、粮食作物种植农户、土地相对规模大的农户受到政策带来的增收效应更加明显。因此,我国各地应稳定土地承包权,积极响应农地经营权抵押贷款政策,因地制宜鼓励农户实现非农就业,参与土地经营权抵押,实现农业生产经营规模化,拓宽农户增收渠道。

交通基础设施改善促进了城市经济高质量发展吗?--基于高铁开通的准自然实验

基于2003—2018年中国278个地级市数据,构建多时点DID模型分析高铁对城市经济高质量发展的影响和具体作用路径。研究发现:(1)高铁开通对城市经济的高质量发展具有显著的促进作用,并且这种促进效应随时间呈现出增强的趋势;(2)高铁开通主要是通过提升城市的配置效应、创新能力以及助推产业结构升级来提高经济高质量发展水平;(3)高铁开通对城市经济高质量发展的拉动作用在东部城市、直辖市、副省级城市以及大型城市更强。上述研究为理解高铁建设与城市经济发展之间的关系提供了新的经验证据,也为进一步优化高铁布局提供了有益的政策启示。