Combined Optimal Dispatch of Thermal Power Generators and Energy Storage Considering Thermal Power Deep Peak Clipping and Wind Energy Emission Grading Punishment

Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal power generators and BESS(battery energy storage system)taking wind energy emission grading punishment and deep peak clipping into consideration.Firstly,in order to minimize wind abandonment,a hierarchical wind abandonment penalty strategy based on fuzzy control is designed and introduced,and the optimal grid-connected power of wind energy is determined as a result of minimizing the peak cutting cost of the system.Secondly,considering BESS and thermal power,the management approach of BESS-assisted virtual peak clipping of thermal power generators is aimed at reducing the degree of deep peak clipping of thermal power generators and optimizing the output of thermal power generators and the charging and discharging power of BESS.Finally,Give an example of how this strategy has been effective in reducing abandonment rates by 0.66% and 7.46% individually for different wind penetration programs,and the daily average can reduce the peak clipping power output of thermal power generators by 42.97 and 72.31 MWh and enhances the effect and economy of system peak clipping.

Analysis of factors influencing carbon emissions in the Yangtze River Delta region and projections of carbon peak scenarios

Based on the supply-side perspective,the improved STIRPAT model is applied to reveal the mechanisms of supply-side factors such as human,capital,technology,industrial synergy,institutions and economic growth on carbon emissions in the Yangtze River Delta(YRD)through path analysis,and to forecast carbon emissions in the YRD from the baseline scenario,factor regulation scenario and integrated scenario to reach the peak.The results show that:(1)Jiangsu's high carbon emission pattern is the main reason for the YRD hindering the synergistic regulation of carbon emissions.(2)Human factors,institutional factors and economic growth factors can all contribute to carbon emissions in the YRD region,while technological and industrial factors can generally suppress carbon emissions in the YRD region.(3)Under the capital regulation scenario,the YRD region has the highest level of carbon emission synergy,with Jiangsu reaching its peak five years earlier.Under the balanced regulation scenario,the YRD region as a whole,Jiangsu,Zhejiang and Anhui reach the peak as scheduled.

Physics-informed machine learning model for prediction of ground reflected wave peak overpressure

The accurate prediction of peak overpressure of explosion shockwaves is significant in fields such as explosion hazard assessment and structural protection, where explosion shockwaves serve as typical destructive elements. Aiming at the problem of insufficient accuracy of the existing physical models for predicting the peak overpressure of ground reflected waves, two physics-informed machine learning models are constructed. The results demonstrate that the machine learning models, which incorporate physical information by predicting the deviation between the physical model and actual values and adding a physical loss term in the loss function, can accurately predict both the training and out-oftraining dataset. Compared to existing physical models, the average relative error in the predicted training domain is reduced from 17.459%-48.588% to 2%, and the proportion of average relative error less than 20% increased from 0% to 59.4% to more than 99%. In addition, the relative average error outside the prediction training set range is reduced from 14.496%-29.389% to 5%, and the proportion of relative average error less than 20% increased from 0% to 71.39% to more than 99%. The inclusion of a physical loss term enforcing monotonicity in the loss function effectively improves the extrapolation performance of machine learning. The findings of this study provide valuable reference for explosion hazard assessment and anti-explosion structural design in various fields.

Estimation of peak wave period from surface texture motion in videos

Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave information from videos will be affected by the interference of the fine ripples on the sea surface.To solve this problem,this study develops a method for estimating peak wave periods from videos captured at low grazing angles.The method extracts the motion of the sea surface texture from the video and obtains the peak wave period via the spectral analysis.The calculation results captured from real-world videos are compared with those obtained from X-band radar inversion and tracking buoy movement,with maximum deviations of 8%and 14%,respectively.The analysis of the results shows that the peak wave period of the method has good stability.In addition,this paper uses a pinhole camera model to convert the displacement of the texture from pixel height to actual height and performs moving average filtering on the displacement of the texture,thus conducting a preliminary exploration of the inversion of significant wave height.This study helps to extend the application of sea surface videos.

Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China

Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China.

Peak Shaving Strategy of Concentrating Solar Power Generation Based on Multi-Time-Scale and Considering Demand Response

According to the multi-time-scale characteristics of power generation and demand-side response(DR)resources,as well as the improvement of prediction accuracy along with the approaching operating point,a rolling peak shaving optimization model consisting of three different time scales has been proposed.The proposed peak shaving optimization model considers not only the generation resources of two different response speeds but also the two different DR resources and determines each unit combination,generation power,and demand response strategy on different time scales so as to participate in the peaking of the power system by taking full advantage of the fast response characteristics of the concentrating solar power(CSP).At the same time,in order to improve the accuracy of the scheduling results,the combination of the day-ahead peak shaving phase with scenario-based stochastic programming can further reduce the influence of wind power prediction errors on scheduling results.The testing results have shown that by optimizing the allocation of scheduling resources in each phase,it can effectively reduce the number of starts and stops of thermal power units and improve the economic efficiency of system operation.The spinning reserve capacity is reduced,and the effectiveness of the peak shaving strategy is verified.

Analysis of Smooth Cepstral Peak Prominence in Hypokinetic Dysarthria Associated With Parkinson’s Disease

Smoothed cepstral peak prominence(CPPs)is a measurement of the distance from the prominent cepstral peak to the linear regression line directly beneath it.Variations of CPPs data acquisition and analysis lead to the complexity of the clinical cut-off values,and there are no agreeable values for a specific voice disorder,such as hypokinetic dysarthria associated with Parkinson’s disease(PD).This study examined the CPPs in people with hypokinetic dysarthria associated with PD compared with healthy participants.Results demonstrated significant differences in speech tasks of sustained vowel and connected speech,with CPPs of connected speech more sensitive to dysphonia and gender difference in PD participants.Males in PD participants presented higher CPPs for sustained vowels and lower CPPs for connected speech than females.It is implied that a consistent clinical application protocol is necessary,and multiple acoustic measures are needed to ensure the accuracy of clinical decisions.

Assessment of Axial Power Peaking Factors in GHARR-1 LEU Core: A Decadal Simulation Analysis

This study aims to thoroughly investigate the axial power peaking factors (PPF) within the low-enriched uranium (LEU) core of the Ghana Research Reactor-1 (GHARR-1). This study uses advanced simulation tools, like the MCNPX code for analysing neutron behavior and the PARET/ANL code for understanding power variations, to get a clearer picture of the reactor’s performance. The analysis covers the initial six years of GHARR-1’s operation and includes projections for its whole 60-year lifespan. We closely observed the patterns of both the highest and average PPFs at 21 axial nodes, with measurements taken every ten years. The findings of this study reveal important patterns in power distribution within the core, which are essential for improving the safety regulations and fuel management techniques of the reactor. We provide a meticulous approach, extensive data, and an analysis of the findings, highlighting the significance of continuous monitoring and analysis for proactive management of nuclear reactors. The findings of this study not only enhance our comprehension of nuclear reactor safety but also carry significant ramifications for sustainable energy progress in Ghana and the wider global context. Nuclear engineering is essential in tackling global concerns, such as the demand for clean and dependable energy sources. Research on optimising nuclear reactors, particularly in terms of safety and efficiency, is crucial for the ongoing advancement and acceptance of nuclear energy.

Quantitative prediction of channel sand bodies based on seismic peak attributes in the frequency domain and its application

The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness prediction of channel sand bodies based on seismic peak attributes in the frequency domain.Using seismic forward modeling of a typical thin channel sand body,a new seismic attribute-the ratio of peak frequency to amplitude was constructed.Theoretical study demonstrated that seismic peak frequency is sensitive to the thickness of the channel sand bodies,while the amplitude attribute is sensitive to the strata lithology.The ratio of the two attributes can highlight the boundaries of the channel sand body.Moreover,the thickness of the thin channel sand bodies can be determined using the relationship between seismic peak frequency and thin layer thickness.Practical applications have demonstrated that the seismic peak frequency attribute can depict the horizontal distribution characteristics of channels very well.The ratio of peak frequency to amplitude attribute can improve the identification ability of channel sand body boundaries.Quantitative prediction and boundary identification of channel sand bodies with seismic peak attributes in the frequency domain are feasible.

465名正常成人QT peak离散度研究

目的:探讨正常成人QTpeak离散度(QTpd)的正常范围及不同测量者之间的测量误差。方法:对465名正常成人以25mm/s纸速记录常规12导联同步心电图。测量QTpd及QTd并比较不同测量者之间QTpd的测量误差。结果:最小QTpeak79%出现于V2导联,最大QTpeak43%出现于V6导联、37%出现于aVF导联。465名正常成人QTpd为10ms～55ms(30±10)ms,不同测量者之间测量结果差异无显著性,QTpd与QTd结果的相关性好。结论:465名正常成人QTpd为10ms～55ms(30±10)ms。12导联同步心电图测量QTpd具有简单、准确的优点。

A DBRTD with a High PVCR and a Peak Current Density at Room Temperature

AlAs/GaAs/In0.1Ga0.9As/GaAs/AlAs double-barrier resonant tunneling diodes （DBRTDs） grown on a semi-insulated GaAs substrate with molecular beam epitaxy is demonstrated. By sandwiching the In0.1 Ga0.9 As layer between GaAs layers, potential wells beside the two sides of barrier are deepened, resulting in an increase of the peak-to-valley current ratio （PVCR） and a peak current density. A special shape of collector is designed in order to reduce contact resistance and non-uniformity of the current;as a result the total chrrent density in the device is increased. The use of thin barriers is also helpful for the improvement of the PVCR and the peak current density in DBRTDs. The devices exhibit a maximum PVCR of 13.98 and a peak current density of 89kA/cm^2 at room temperature.

Peak Metals, Minerals, Energy, Wealth, Food and Population： Urgent Policy Considerations for a Sustainable Society

Several strategic metals, elements and energy resources are about to run into scarcity in the near future under the present paradigm of use. A global systems model has been developed （WORLD） to assess the issue of scarcity and its implications for society. We show that scarcity may lead to ＂peak wealth＂, ＂peak population＂, ＂peak waste＂ and ＂peak civilization＂, unless urgent counter-measures are systematically undertaken. Materials that underpin modern society may become unavailable for global mass production of goods. The material volumes that can be supplied from fossil reserves will be reduced with respect to today and resources will go up in price. The future resource supply is unsustainable without comprehensive recycling. The creation of wealth from conversion of resources and work, as well as the current extensive borrowing from the future, cause concerns that peaking energy and materials production may lead to ＂peak wealth＂ and the end of the golden age we live in. Our policy recommendations are that governments must take this issue seriously and must immediately start preparing legislations to close material cycles, optimize energy use and minimize irreversible material losses. Research efforts need to be based on systems thinking and a concerted effort is needed.

Chopping-peaking开关形成高功率超宽带双极脉冲的实验研究

设计研制了一种chopping peaking组合开关型高功率双极脉冲形成装置,通过调节两个开关的导通时刻来得到不同形状的双极脉冲。理想情况下,形成的双极脉冲电压峰 峰值等于入射脉冲峰值电压的2倍,实验中入射脉冲峰值电压为205kV的单极脉冲,获得了最大峰 峰电压为360kV的双极脉冲,是入射脉冲峰值电压的1.76倍。双极脉冲的持续时间可以改变,最大值为单极脉冲的脉宽。入射脉冲上升时间越小,得到的双极脉冲峰 峰电压就越大。

O_2 peak:释义与应用

O2 peak常用于评价不同人群有氧工作能力,是近年来国外运动医学文献中出现频度较高的一个专业术语。就O2 peak这一术语的解释、与O2 max的区别、应用范围以及再测信度进行了综述。尽管学者们对.O2 peak有着不同的解释,但是,O2 peak在研究对象、判断标准、运动负荷方法等方面与.O2 max存在明显的差异。O2 peak常用于不同人群的流行病学研究,具有较高的实用性。许多研究表明,O2 peak有很高的再测信度,是一项稳定性较好的测试指标。

Peak Electricity Demand Management and Energy Efficiency among Large Steel Manufacturing Firms in Nairobi Region, Kenya

To reduce peak electricity demand and hence reduce capacity costs due to added investment of generating additional power to meet short intervals of peak demand, can enhance energy efficiency. Where it is possible to adjust timing and the quantity of electricity consumption and at the same time achieve the same useful effect, the value of the energy service itself remains unchanged. Peak demand management is viewed as the balance between demand and generation of energy hence an important requirement for stabilized operation of power system. Therefore, the purpose of this study was to establish the correlation between peak electricity demand management strategies and energy efficiency among large steel manufacturing firms in Nairobi, Kenya. The strategies investigated were demand scheduling, Peak shrinking and Peak shaving. Demand scheduling involves shifting predetermined loads to low peak periods thereby flattening the demand curve. Peak shrinking on the other hand involves installation of energy efficient equipment thereby shifting the overall demand curve downwards. Peak shaving is the deployment of secondary generation on site to temporarily power some loads during peak hours thereby reducing demand during the peak periods of the plant. The specific objectives were to test the relationship between demand scheduling and energy efficiency among large steel manufacturing firms in Nairobi Region;to test the correlation between peak shrinking and energy efficiency among large steel manufacturing firms in Nairobi Region;and to test the association between peak shaving and energy efficiency among large steel manufacturing firms in Nairobi Region. The study adopted a descriptive research design to determine the relationship between each independent variable namely demand scheduling, peak shrinking, peak shaving and the dependent variable, the energy efficiency. The target population was large steel manufacturing firms in Nairobi Region, Kenya. The study used both primary and secondary data. The primary data was from structured questionnaires while secondary data was from historical electricity consumption data for the firms under study. The results revealed that both peak shrinking and peak shaving were statistically significant in influencing energy efficiency among the steel manufacturing firms in Nairobi Region, each with Pearson correlation coefficient of 0.903, thus a strong linear relationship between the investigated strategy and the dependent variable, energy efficiency. The obtained results are significant at probability value of 0.005 (p 0.05). The conclusion is that peak shrinking and peak shaving have an impact on energy efficiency in the population under study, and if properly implemented, may lead to efficient utilization of the available energy. The study further recommended that peak demand management practices need to be implemented efficiently as a way of improving the overall plant load factor and energy efficiency.

Overlapped peaks resolution for linear sweep polarography using Gaussian-like distribution

A resolution method based on Gaussian-like distribution for overlapped linear sweep polarographic peaks was proposed to simultaneously detect the polymetallic components, such as Zn（Ⅱ） and Co（Ⅱ）, coexisting in the leaching solution of zinc hydrometallurgy. A Gaussian-like distribution was constructed as the sub-model of overlapped peaks by analyzing the characteristics of linear sweep polarographic curve. Then, the abscissas of each peak and trough were pinpointed through multi-resolution wavelet decomposition, the curve and its derivative curves were fitted by using nonlinear weighted least squares （NWLS）. Finally, overlapped peaks were resolved into independent sub-peaks based on fitted reconstruction parameters. The experimental results show that the relative error of half-wave potential pinpointed by multi-resolution wavelet decomposition is less than 1% and the accuracy of Ip fitted by NWLS is higher than 96%. The proposed resolution method is effective for overlapped linear sweep polarographic peaks of Zn（Ⅱ） and Co（Ⅱ）.

不同耐力跑测试评价VO_(2max)/VO_(2peak)效度的比较研究

目的:梳理采用不同耐力跑测试[800 m跑、805 m跑、1500 m跑、1609 m跑、12 min跑、20 m往返跑(20 m SRT)]评价健康人群VO_(2max)/VO_(2peak)的效度研究,系统比较不同测试方法的效度差异。方法:检索了LISTA(EBSCO)、PubMed(NLM)、Web of Science(TS)与中国知网(CNKI)数据库,采用Castro-Piňero的文献质量评价标准对纳入文献进行质量评价(Ross et al.,2016)。结果:800 m、805 m、1000 m跑时间与VO_(2max)/VO_(2peak)的相关系数(r):男性儿童青少年为-0.224~-0.781,女性为-0.495~-0.697;男性成年人群为-0.219~-0.736,女性为-0.139~-0.626。1500 m、1609 m跑时间与VO_(2max)/VO_(2peak)的r值:儿童、青少年为-0.603~-0.790;成年人群为-0.627~-0.729。12 min跑距离与VO_(2max)/VO_(2peak)r值:青少年儿童0.977(男)、0.964(女);成年人群为0.730~0.897,预测方程的R值为0.87,0.872(男)、0.862(女)。20 m SRT预测方程值与直接测量VO_(2max)的r值:青少年儿童为0.60~0.90,决定系数(R2)为0.46~0.81,标准误(SEE)为3.33~7.26 ml·kg^(-1)·min^(-1);成年人群为0.43~0.94,R2为0.87~0.88,SEE为1.38~3.00 ml·kg^(-1)·min^(-1)。结论:作为有氧能力(VO_(2max)/VO_(2peak))的间接评价方法,800 m、805 m、1000 m跑效度最低,波动幅度大;1500 m、1609 m跑效度较高,适用人群广泛;12 min跑、20 m SRT效度最高,并且效度稳定。在实际应用中,应根据研究目的、监测人群合理选择,谨慎解读其监测结果。针对我国人群的耐力跑评测有氧能力(VO_(2max)/VO_(2peak))效度的研究有待进一步开展。

吸气肌力量训练对大学生VO_2peak的影响

探讨吸气肌力量训练是否会影响以主观感觉为主要判定标准的VO2peak值。观察了为期4周的吸气肌力量训练(训练负荷为80%MIP,30次/30分/天,5天/周,共20个训练周期)过程中VO2peak值及运动能力的动态改变。VO2peak测定采用德国耶格公司生产的MasterScreen CPX运动肺功能仪。随吸气肌训练周期的延长,吸气肌力量、GXT运动持续时间及完成的最大负荷值以及VO2peak的绝对值和相对值均呈显著性意义的增加(P<0.01),但RPE值则没有显著性意义的改变(P>0.05);而对照组则没有显著性意义的改变(P>0.05)。说明4周吸气肌力量训练可显著性提高以主观感觉为主要判定标准的VO2peak值以及递增负荷运动试验(GXT)的运动能力。

吸气肌训练对健康大学生VO_2peak、肺功能及运动能力的影响

探讨呼吸肌训练能否影响以主观感觉为主要判定标准的VO2peak值以及肺功能和运动能力。方法:观察了为期4周的吸气肌力量训练过程中VO2peak值、肺功能及运动能力的动态改变。结果:随吸气肌训练周期的延长,吸气肌力量、GXT运动持续时间及完成的最大负荷值以及VO2peak的绝对值和相对值均呈显著性意义的增加(P<0.01);而对照组则没有显著性意义的改变(P>0.05)。MV、VCmax和FEV1均没有显著性意义的差异(P>0.05)。结论:4周吸气肌力量训练可显著性提高以主观感觉为主要判定标准的VO2peak值以及递增负荷运动试验(GXT)的运动能力。

Direct use of peak ground motion parameters for the estimation of inelastic displacement ratio of SDOF systems subjected to repeated far fault ground motions

This study is aimed at developing statistical equations to estimate the inelastic displacement ratio of singledegree-of-freedom systems subjected to far fault repeated earthquakes. In the study, peak ground motion parameters are used to define the scatter of the original data. The ratio of peak ground acceleration to peak ground velocity, and peak ground velocity of the ground motion records and structural parameters such as period of vibration and lateral strength ratio are used in the proposed equations. For the development of the equations, nonlinear time history analyses of single-degree-offreedom systems are conducted. Then, the results are used in a multivariate regression procedure. The equations are verified by comparing the estimated results with the calculated results. The average error and coefficient of variation of the proposed equations are presented. The analyses results revealed that the direct use of peak ground motion parameters for the estimation of inelastic displacement ratio significantly reduced the scatter in the original data and yielded accurate results. From the comparative results it is also observed that results obtained using equations specific to peak ground velocity or peak ground acceleration to peak ground velocity ratio are similar.