本文基于马丁评价理论下的态度系统,对赛珍珠的语篇A Debt to Dickens进行研究。赛珍珠“文化边缘人”的身份,给她的生活带来了很多不安和惆怅,前期在众多东方人面孔的乡村,村民对其异域特色的样貌有许多偏见,因此她多用负面的判断和鉴...本文基于马丁评价理论下的态度系统,对赛珍珠的语篇A Debt to Dickens进行研究。赛珍珠“文化边缘人”的身份,给她的生活带来了很多不安和惆怅,前期在众多东方人面孔的乡村,村民对其异域特色的样貌有许多偏见,因此她多用负面的判断和鉴赏资源描述了一段孤独的生活;后期其寻找到小说的快乐后,沉迷于阅读的魅力,所以多用正面的判断和鉴赏资源写出了她的明朗。研究发现,全文的判断和鉴赏资源数量较多,情感资源出现较少。态度系统有利于分析文本所暗含的感情走向,给读者理解文本提供了一个新的视角。展开更多
Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a s...Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a single prediction model is hard to capture temporal features effectively, resulting in diminished predictionaccuracy. In this study, a hybrid deep learning framework that integrates attention mechanism, convolution neuralnetwork (CNN), improved chaotic particle swarm optimization (ICPSO), and long short-term memory (LSTM), isproposed for short-term household load forecasting. Firstly, the CNN model is employed to extract features fromthe original data, enhancing the quality of data features. Subsequently, the moving average method is used for datapreprocessing, followed by the application of the LSTM network to predict the processed data. Moreover, the ICPSOalgorithm is introduced to optimize the parameters of LSTM, aimed at boosting the model’s running speed andaccuracy. Finally, the attention mechanism is employed to optimize the output value of LSTM, effectively addressinginformation loss in LSTM induced by lengthy sequences and further elevating prediction accuracy. According tothe numerical analysis, the accuracy and effectiveness of the proposed hybrid model have been verified. It canexplore data features adeptly, achieving superior prediction accuracy compared to other forecasting methods forthe household load exhibiting significant fluctuations across different seasons.展开更多
Creditors,such as banks,often use disclosed environmental information to assess a company’s environmental risk and ensure the safety of debt funds.Consequently,carbon disclosures have become an important consideratio...Creditors,such as banks,often use disclosed environmental information to assess a company’s environmental risk and ensure the safety of debt funds.Consequently,carbon disclosures have become an important consideration for creditors when making investments.This study explores the relationship between carbon disclosure and debt financing costs using data on listed companies from 2008 to 2019.The results show that carbon disclosure can reduce the debt financing costs of enterprises,and that this influence is more significant for private companies than for state-owned enterprises.Instrumental variables and Propensity Score Matching(PSM)were used to evaluate the robustness of negative relationships.Furthermore,carbon disclosure has a more significant impact on debt costs with less environmental supervision pressure,weak residents’environmental awareness,and weak product market competition.These findings provide guidance for companies’carbon information disclosure and support the establishment of official carbon disclosure standards.展开更多
Accurate forecasting of time series is crucial across various domains.Many prediction tasks rely on effectively segmenting,matching,and time series data alignment.For instance,regardless of time series with the same g...Accurate forecasting of time series is crucial across various domains.Many prediction tasks rely on effectively segmenting,matching,and time series data alignment.For instance,regardless of time series with the same granularity,segmenting them into different granularity events can effectively mitigate the impact of varying time scales on prediction accuracy.However,these events of varying granularity frequently intersect with each other,which may possess unequal durations.Even minor differences can result in significant errors when matching time series with future trends.Besides,directly using matched events but unaligned events as state vectors in machine learning-based prediction models can lead to insufficient prediction accuracy.Therefore,this paper proposes a short-term forecasting method for time series based on a multi-granularity event,MGE-SP(multi-granularity event-based short-termprediction).First,amethodological framework for MGE-SP established guides the implementation steps.The framework consists of three key steps,including multi-granularity event matching based on the LTF(latest time first)strategy,multi-granularity event alignment using a piecewise aggregate approximation based on the compression ratio,and a short-term prediction model based on XGBoost.The data from a nationwide online car-hailing service in China ensures the method’s reliability.The average RMSE(root mean square error)and MAE(mean absolute error)of the proposed method are 3.204 and 2.360,lower than the respective values of 4.056 and 3.101 obtained using theARIMA(autoregressive integratedmoving average)method,as well as the values of 4.278 and 2.994 obtained using k-means-SVR(support vector regression)method.The other experiment is conducted on stock data froma public data set.The proposed method achieved an average RMSE and MAE of 0.836 and 0.696,lower than the respective values of 1.019 and 0.844 obtained using the ARIMA method,as well as the values of 1.350 and 1.172 obtained using the k-means-SVR method.展开更多
BACKGROUND Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer,the prognostic value of hematocrit for colorectal cancer(CRC)patients has...BACKGROUND Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer,the prognostic value of hematocrit for colorectal cancer(CRC)patients has not been determined.The prognostic value of red blood cell distribution width(RDW)for CRC patients was controversial.AIM To investigate the impact of RDW and hematocrit on the short-term outcomes and long-term prognosis of CRC patients who underwent radical surgery.METHODS Patients who were diagnosed with CRC and underwent radical CRC resection between January 2011 and January 2020 at a single clinical center were included.The short-term outcomes,overall survival(OS)and disease-free survival(DFS)were compared among the different groups.Cox analysis was also conducted to identify independent risk factors for OS and DFS.RESULTS There were 4258 CRC patients who underwent radical surgery included in our study.A total of 1573 patients were in the lower RDW group and 2685 patients were in the higher RDW group.There were 2166 and 2092 patients in the higher hematocrit group and lower hematocrit group,respectively.Patients in the higher RDW group had more intraoperative blood loss(P<0.01)and more overall complications(P<0.01)than did those in the lower RDW group.Similarly,patients in the lower hematocrit group had more intraoperative blood loss(P=0.012),longer hospital stay(P=0.016)and overall complications(P<0.01)than did those in the higher hematocrit group.The higher RDW group had a worse OS and DFS than did the lower RDW group for tumor node metastasis(TNM)stage I(OS,P<0.05;DFS,P=0.001)and stage II(OS,P=0.004;DFS,P=0.01)than the lower RDW group;the lower hematocrit group had worse OS and DFS for TNM stage II(OS,P<0.05;DFS,P=0.001)and stage III(OS,P=0.001;DFS,P=0.001)than did the higher hematocrit group.Preoperative hematocrit was an independent risk factor for OS[P=0.017,hazard ratio(HR)=1.256,95%confidence interval(CI):1.041-1.515]and DFS(P=0.035,HR=1.194,95%CI:1.013-1.408).CONCLUSION A higher preoperative RDW and lower hematocrit were associated with more postoperative complications.However,only hematocrit was an independent risk factor for OS and DFS in CRC patients who underwent radical surgery,while RDW was not.展开更多
This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study ...This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study finds that state-owned capital participation significantly reduces the debt financing costs of private enterprises and expands the scale of their debt financing.This conclusion remains valid after a series of endogeneity and robustness tests.Further analysis of the mechanism reveals that state-owned capital participation improves the debt financing of private enterprises through multiple channels:Enhancing their social reputation,mitigating the“statistical bias”they face,optimizing their information quality,and reducing the“shareholder-creditor”agency problems.This paper conceptualizes these benefits as the“complementary advantages of heterogeneous shareholders”.This not only constructs a theoretical framework for“reverse mixed-ownership reform”but also better narrates the Chinese story of“mixed-ownership reform”by adopting a more universally applicable theory of equity structure.Additionally,the paper supplements existing research on the macro-and meso-level relationship between the government and the market by exploring the government’s positive role at the micro-level.展开更多
Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currentl...Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currently,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM prediction.Besides,the weighted LS+AR hybrid method performs well for PM short-term prediction.However,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR model.In this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid method.By using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid method.Compared to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,respectively.Besides,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.展开更多
With the advancement of artificial intelligence,traffic forecasting is gaining more and more interest in optimizing route planning and enhancing service quality.Traffic volume is an influential parameter for planning ...With the advancement of artificial intelligence,traffic forecasting is gaining more and more interest in optimizing route planning and enhancing service quality.Traffic volume is an influential parameter for planning and operating traffic structures.This study proposed an improved ensemble-based deep learning method to solve traffic volume prediction problems.A set of optimal hyperparameters is also applied for the suggested approach to improve the performance of the learning process.The fusion of these methodologies aims to harness ensemble empirical mode decomposition’s capacity to discern complex traffic patterns and long short-term memory’s proficiency in learning temporal relationships.Firstly,a dataset for automatic vehicle identification is obtained and utilized in the preprocessing stage of the ensemble empirical mode decomposition model.The second aspect involves predicting traffic volume using the long short-term memory algorithm.Next,the study employs a trial-and-error approach to select a set of optimal hyperparameters,including the lookback window,the number of neurons in the hidden layers,and the gradient descent optimization.Finally,the fusion of the obtained results leads to a final traffic volume prediction.The experimental results show that the proposed method outperforms other benchmarks regarding various evaluation measures,including mean absolute error,root mean squared error,mean absolute percentage error,and R-squared.The achieved R-squared value reaches an impressive 98%,while the other evaluation indices surpass the competing.These findings highlight the accuracy of traffic pattern prediction.Consequently,this offers promising prospects for enhancing transportation management systems and urban infrastructure planning.展开更多
With the continuous advancement of China’s“peak carbon dioxide emissions and Carbon Neutrality”process,the proportion of wind power is increasing.In the current research,aiming at the problem that the forecasting m...With the continuous advancement of China’s“peak carbon dioxide emissions and Carbon Neutrality”process,the proportion of wind power is increasing.In the current research,aiming at the problem that the forecasting model is outdated due to the continuous updating of wind power data,a short-term wind power forecasting algorithm based on Incremental Learning-Bagging Deep Hybrid Kernel Extreme Learning Machine(IL-Bagging-DHKELM)error affinity propagation cluster analysis is proposed.The algorithm effectively combines deep hybrid kernel extreme learning machine(DHKELM)with incremental learning(IL).Firstly,an initial wind power prediction model is trained using the Bagging-DHKELM model.Secondly,Euclidean morphological distance affinity propagation AP clustering algorithm is used to cluster and analyze the prediction error of wind power obtained from the initial training model.Finally,the correlation between wind power prediction errors and Numerical Weather Prediction(NWP)data is introduced as incremental updates to the initial wind power prediction model.During the incremental learning process,multiple error performance indicators are used to measure the overall model performance,thereby enabling incremental updates of wind power models.Practical examples show the method proposed in this article reduces the root mean square error of the initial model by 1.9 percentage points,indicating that this method can be better adapted to the current scenario of the continuous increase in wind power penetration rate.The accuracy and precision of wind power generation prediction are effectively improved through the method.展开更多
This study observes and explores a puzzle in Chinese firms whereby both cash holdings and short-term debt simultaneously account for more than 20% of total assets for at least two consecutive years over the sample per...This study observes and explores a puzzle in Chinese firms whereby both cash holdings and short-term debt simultaneously account for more than 20% of total assets for at least two consecutive years over the sample period. This phenomenon conflicts with the principle of corporate value maximization, and is not clearly explained by the classical theories in corporate finance. Based on the implications in the extant literature and discussions of institutional constraints of the transition economy in China, this paper develops four hypotheses that are involved with agency conflicts between the largest shareholders and creditors and the formation of this puzzling financial structure. The empirical analyses suggest that the largest shareholders with tunneling motives seek to hold more cash to serve their private interests and/or the consequent operational deficit of the listed corporations. To the ends, these corporations tend to manage the timing of short term debt financing to increase cash reserves temporarily at the end of year. Essentially, greater cash holdings on the balance sheet of these corporations related with the puzzle become a misleading signal for potential creditors, possibly contributing to the refinancing of short-term debt of these listed firms for the following year. Hence, the puzzling financial structure is connected with the timing of debt financing and adverse selection of creditors. This study enriches the stream of literature on cash holdings and debt maturity, and provides new evidence on the impact of agency problems of the largest shareholders on the association between cash holdings and debt maturity in the context of a transition economy.展开更多
The numerical simulation and slope stability prediction are the focus of slope disaster research.Recently,machine learning models are commonly used in the slope stability prediction.However,these machine learning mode...The numerical simulation and slope stability prediction are the focus of slope disaster research.Recently,machine learning models are commonly used in the slope stability prediction.However,these machine learning models have some problems,such as poor nonlinear performance,local optimum and incomplete factors feature extraction.These issues can affect the accuracy of slope stability prediction.Therefore,a deep learning algorithm called Long short-term memory(LSTM)has been innovatively proposed to predict slope stability.Taking the Ganzhou City in China as the study area,the landslide inventory and their characteristics of geotechnical parameters,slope height and slope angle are analyzed.Based on these characteristics,typical soil slopes are constructed using the Geo-Studio software.Five control factors affecting slope stability,including slope height,slope angle,internal friction angle,cohesion and volumetric weight,are selected to form different slope and construct model input variables.Then,the limit equilibrium method is used to calculate the stability coefficients of these typical soil slopes under different control factors.Each slope stability coefficient and its corresponding control factors is a slope sample.As a result,a total of 2160 training samples and 450 testing samples are constructed.These sample sets are imported into LSTM for modelling and compared with the support vector machine(SVM),random forest(RF)and convo-lutional neural network(CNN).The results show that the LSTM overcomes the problem that the commonly used machine learning models have difficulty extracting global features.Furthermore,LSTM has a better prediction performance for slope stability compared to SVM,RF and CNN models.展开更多
Background:This study was designed to investigate the feasibility of tumor-infiltrating immune cells with different phenotypic characteristics for predicting short-term clinical responses in patients with locally adva...Background:This study was designed to investigate the feasibility of tumor-infiltrating immune cells with different phenotypic characteristics for predicting short-term clinical responses in patients with locally advanced cervical cancer(LACC).Methods:Thirty-four patients who received concurrent chemoradiotherapy and twenty-one patients who merely underwent radiotherapy were enrolled in this study.We retrospectively analyzed the T cell markers(i.e.,CD3,CD4,CD8),memory markers(i.e.,CD45,CCR7),and differentiation markers(i.e.,CD27)in the peripheral blood and tumor tissues of patients with LACC before treatment based on flow cytometry.We also analyzed the relationship of T cell subsets between peripheral blood and tumor tissues,and their correlation with complete response or partial response.Results:The percentage of central memory CD8^(+)TCM(CD8^(+)CD45RA^(−)CD27^(+)CCR7^(+))cells in LACC patients was significantly lower than that of the control group.The percentage of CD8^(+)TN in the peripheral blood of LACC patients was significantly higher than that of tumor tissues.CD8^(+)TEM in the peripheral blood was significantly lower than that of tumor tissues.The percentage of CD8^(+)TN and CD8^(+)TCM in human papillomavirus(HPV)positive samples was significantly higher than that of HPV-negative samples.Similarly,the percentage of CD8^(+)TCM in tumor tissues was significantly higher in cancer tissue samples with lymph nodes compared with those without.Conclusion:A higher proportion of CD4^(+)TCM and a lower proportion of CD8^(+)TN in the tumor microenvironment of LACC may contribute to the therapy response prediction.展开更多
Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy transactio...Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy transactions.STLF ranges from an hour ahead prediction to a day ahead prediction. Variouselectric load forecasting methods have been used in literature for electricitygeneration planning to meet future load demand. A perfect balance regardinggeneration and utilization is still lacking to avoid extra generation and misusageof electric load. Therefore, this paper utilizes Levenberg–Marquardt(LM) based Artificial Neural Network (ANN) technique to forecast theshort-term electricity load for smart grids in a much better, more precise,and more accurate manner. For proper load forecasting, we take the mostcritical weather parameters along with historical load data in the form of timeseries grouped into seasons, i.e., winter and summer. Further, the presentedmodel deals with each season’s load data by splitting it into weekdays andweekends. The historical load data of three years have been used to forecastweek-ahead and day-ahead load demand after every thirty minutes makingload forecast for a very short period. The proposed model is optimized usingthe Levenberg-Marquardt backpropagation algorithm to achieve results withcomparable statistics. Mean Absolute Percent Error (MAPE), Root MeanSquared Error (RMSE), R2, and R are used to evaluate the model. Comparedwith other recent machine learning-based mechanisms, our model presentsthe best experimental results with MAPE and R2 scores of 1.3 and 0.99,respectively. The results prove that the proposed LM-based ANN modelperforms much better in accuracy and has the lowest error rates as comparedto existing work.展开更多
BACKGROUND Obesity is a state in which excess heat is converted into excess fat,which accumulates in the body and may cause damage to multiple organs of the circulatory,endocrine,and digestive systems.Studies have sho...BACKGROUND Obesity is a state in which excess heat is converted into excess fat,which accumulates in the body and may cause damage to multiple organs of the circulatory,endocrine,and digestive systems.Studies have shown that the accumulation of abdominal fat and mesenteric fat hypertrophy in patients with obesity makes laparoscopic surgery highly difficult,which is not conducive to operation and affects patient prognosis.However,there is still controversy regarding these conclusions.AIM To explore the relationship between body mass index(BMI)and short-term prognosis after surgery for colorectal cancer.METHODS PubMed,Embase,Ovid,Web of Science,CNKI,and China Biology Medicine Disc databases were searched to obtain relevant articles on this topic.After the articles were screened according to the inclusion and exclusion criteria and the risk of literature bias was assessed using the Newcastle-Ottawa Scale,the prognostic indicators were combined and analyzed.RESULTS A total of 16 articles were included for quantitative analysis,and 15588 patients undergoing colorectal cancer surgery were included in the study,including 3775 patients with obesity and 11813 patients without obesity.Among them,12 articles used BMI≥30 kg/m^(2)and 4 articles used BMI≥25 kg/m^(2)for the definition of obesity.Four patients underwent robotic colorectal surgery,whereas 12 underwent conventional laparoscopic colorectal resection.The quality of the literature was good.Meta-combined analysis showed that the overall complication rate of patients with obesity after surgery was higher than that of patients without obesity[OR=1.35,95%CI:1.23-1.48,Z=6.25,P<0.0001].The incidence of anastomotic leak after surgery in patients with obesity was not significantly different from that in patients without obesity[OR=0.99,95%CI:0.70-1.41),Z=-0.06,P=0.956].The incidence of surgical site infection(SSI)after surgery in patients with obesity was higher than that in patients without obesity[OR=1.43,95%CI:1.16-1.78,Z=3.31,P<0.001].The incidence of reoperation in patients with obesity after surgery was higher than that in patients without obesity;however,the difference was not statistically significant[OR=1.15,95%CI:0.92-1.45,Z=1.23,P=0.23];Patients with obesity had lower mortality after surgery than patients without obesity;however,the difference was not statistically significant[OR=0.61,95%CI:0.35-1.06,Z=-1.75,P=0.08].Subgroup analysis revealed that the geographical location of the institute was one of the sources of heterogeneity.Robot-assisted surgery was not significantly different from traditional laparoscopic resection in terms of the incidence of complications.CONCLUSION Obesity increases the overall complication and SSI rates of patients undergoing colorectal cancer surgery but has no influence on the incidence of anastomotic leak,reoperation rate,and short-term mortality rate.展开更多
Wind power prediction is very important for the economic dispatching of power systems containing wind power.In this work,a novel short-term wind power prediction method based on improved complete ensemble empirical mo...Wind power prediction is very important for the economic dispatching of power systems containing wind power.In this work,a novel short-term wind power prediction method based on improved complete ensemble empirical mode decomposition with adaptive noise(ICEEMDAN)and(long short-term memory)LSTM neural network is proposed and studied.First,the original data is prepossessed including removing outliers and filling in the gaps.Then,the random forest algorithm is used to sort the importance of each meteorological factor and determine the input climate characteristics of the forecast model.In addition,this study conducts seasonal classification of the annual data where ICEEMDAN is adopted to divide the original wind power sequence into numerous modal components according to different seasons.On this basis,sample entropy is used to calculate the complexity of each component and reconstruct them into trend components,oscillation components,and random components.Then,these three components are input into the LSTM neural network,respectively.Combined with the predicted values of the three components,the overall power prediction results are obtained.The simulation shows that ICEEMDAN-SE-LSTM achieves higher prediction accuracy ranging from 1.57%to 9.46%than other traditional models,which indicates the reliability and effectiveness of the proposed method for power prediction.展开更多
Night lighting has been shown to affect wild animals.To date,the effects of night lighting on the metabolic homeostasis of birds that spend short time in urban environments remain unclear.Using model bird species Zebr...Night lighting has been shown to affect wild animals.To date,the effects of night lighting on the metabolic homeostasis of birds that spend short time in urban environments remain unclear.Using model bird species Zebra Finch(Taeniopygia guttata),we investigated the effects of short-term night lighting on liver transcriptome,blood glucose,triglyceride,and thyroxine(T4 and T3)levels in birds exposed to two different night lighting duration periods(three days and six days).After three days of night lighting exposure,the expression of genes involved in fat synthesis in the liver was upregulated while the expression of genes involved in fatty acid oxidation and triglyceride decomposition was downregulated.There was also a reduction in blood triglyceride,glucose,and T3 concentrations.However,after six days of night lighting,the expression of genes associated with fatty acid decomposition and hyperglycemia in the liver was upregulated,while the expression of genes involved in fat synthesis was downregulated.Simultaneously,blood glucose levels and T3 concentration increased.These findings indicate that short-term exposure to night lighting can disrupt the lipid and glucose metabolism of small passerine birds,and longer stopovers in urban area with intense night lighting may cause birds to consume more lipid energy.展开更多
This study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute ac...This study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute active cycle of the inverter and reactive outputs to reduce network loss and light rejection.In the second stage,the local control stabilizes the fluctuations and tracks the system state of the first stage.The uncertain interval model establishes a chance constraint model for the inverter voltage-reactive power local control.Second-order cone optimization and sensitivity theories were employed to solve the models.The effectiveness of the model was confirmed using a modified IEEE 33 bus example.The intraday control outcome for distributed power generation considering the effects of fluctuation uncertainty,PV penetration rate,and inverter capacity is analyzed.展开更多
A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively ...A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively used and still have considerable potential. In recent years, methods based on deep neural networks have made significant breakthroughs, and fault diagnosis methods for industrial processes based on deep learning have attracted considerable research attention. Therefore, we propose a fusion deeplearning algorithm based on a fully convolutional neural network(FCN) to extract features and build models to correctly diagnose all types of faults. We use long short-term memory(LSTM) units to expand our proposed FCN so that our proposed deep learning model can better extract the time-domain features of chemical process data. We also introduce the attention mechanism into the model, aimed at highlighting the importance of features, which is significant for the fault diagnosis of chemical processes with many features. When applied to the benchmark Tennessee Eastman process, our proposed model exhibits impressive performance, demonstrating the effectiveness of the attention-based LSTM FCN in chemical process fault diagnosis.展开更多
An improved fuzzy time series algorithmbased on clustering is designed in this paper.The algorithm is successfully applied to short-term load forecasting in the distribution stations.Firstly,the K-means clustering met...An improved fuzzy time series algorithmbased on clustering is designed in this paper.The algorithm is successfully applied to short-term load forecasting in the distribution stations.Firstly,the K-means clustering method is used to cluster the data,and the midpoint of two adjacent clustering centers is taken as the dividing point of domain division.On this basis,the data is fuzzed to form a fuzzy time series.Secondly,a high-order fuzzy relation with multiple antecedents is established according to the main measurement indexes of power load,which is used to predict the short-term trend change of load in the distribution stations.Matlab/Simulink simulation results show that the load forecasting errors of the typical fuzzy time series on the time scale of one day and one week are[−50,20]and[−50,30],while the load forecasting errors of the improved fuzzy time series on the time scale of one day and one week are[−20,15]and[−20,25].It shows that the fuzzy time series algorithm improved by clustering improves the prediction accuracy and can effectively predict the short-term load trend of distribution stations.展开更多
文摘本文基于马丁评价理论下的态度系统,对赛珍珠的语篇A Debt to Dickens进行研究。赛珍珠“文化边缘人”的身份,给她的生活带来了很多不安和惆怅,前期在众多东方人面孔的乡村,村民对其异域特色的样貌有许多偏见,因此她多用负面的判断和鉴赏资源描述了一段孤独的生活;后期其寻找到小说的快乐后,沉迷于阅读的魅力,所以多用正面的判断和鉴赏资源写出了她的明朗。研究发现,全文的判断和鉴赏资源数量较多,情感资源出现较少。态度系统有利于分析文本所暗含的感情走向,给读者理解文本提供了一个新的视角。
基金the Shanghai Rising-Star Program(No.22QA1403900)the National Natural Science Foundation of China(No.71804106)the Noncarbon Energy Conversion and Utilization Institute under the Shanghai Class IV Peak Disciplinary Development Program.
文摘Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a single prediction model is hard to capture temporal features effectively, resulting in diminished predictionaccuracy. In this study, a hybrid deep learning framework that integrates attention mechanism, convolution neuralnetwork (CNN), improved chaotic particle swarm optimization (ICPSO), and long short-term memory (LSTM), isproposed for short-term household load forecasting. Firstly, the CNN model is employed to extract features fromthe original data, enhancing the quality of data features. Subsequently, the moving average method is used for datapreprocessing, followed by the application of the LSTM network to predict the processed data. Moreover, the ICPSOalgorithm is introduced to optimize the parameters of LSTM, aimed at boosting the model’s running speed andaccuracy. Finally, the attention mechanism is employed to optimize the output value of LSTM, effectively addressinginformation loss in LSTM induced by lengthy sequences and further elevating prediction accuracy. According tothe numerical analysis, the accuracy and effectiveness of the proposed hybrid model have been verified. It canexplore data features adeptly, achieving superior prediction accuracy compared to other forecasting methods forthe household load exhibiting significant fluctuations across different seasons.
文摘Creditors,such as banks,often use disclosed environmental information to assess a company’s environmental risk and ensure the safety of debt funds.Consequently,carbon disclosures have become an important consideration for creditors when making investments.This study explores the relationship between carbon disclosure and debt financing costs using data on listed companies from 2008 to 2019.The results show that carbon disclosure can reduce the debt financing costs of enterprises,and that this influence is more significant for private companies than for state-owned enterprises.Instrumental variables and Propensity Score Matching(PSM)were used to evaluate the robustness of negative relationships.Furthermore,carbon disclosure has a more significant impact on debt costs with less environmental supervision pressure,weak residents’environmental awareness,and weak product market competition.These findings provide guidance for companies’carbon information disclosure and support the establishment of official carbon disclosure standards.
基金funded by the Fujian Province Science and Technology Plan,China(Grant Number 2019H0017).
文摘Accurate forecasting of time series is crucial across various domains.Many prediction tasks rely on effectively segmenting,matching,and time series data alignment.For instance,regardless of time series with the same granularity,segmenting them into different granularity events can effectively mitigate the impact of varying time scales on prediction accuracy.However,these events of varying granularity frequently intersect with each other,which may possess unequal durations.Even minor differences can result in significant errors when matching time series with future trends.Besides,directly using matched events but unaligned events as state vectors in machine learning-based prediction models can lead to insufficient prediction accuracy.Therefore,this paper proposes a short-term forecasting method for time series based on a multi-granularity event,MGE-SP(multi-granularity event-based short-termprediction).First,amethodological framework for MGE-SP established guides the implementation steps.The framework consists of three key steps,including multi-granularity event matching based on the LTF(latest time first)strategy,multi-granularity event alignment using a piecewise aggregate approximation based on the compression ratio,and a short-term prediction model based on XGBoost.The data from a nationwide online car-hailing service in China ensures the method’s reliability.The average RMSE(root mean square error)and MAE(mean absolute error)of the proposed method are 3.204 and 2.360,lower than the respective values of 4.056 and 3.101 obtained using theARIMA(autoregressive integratedmoving average)method,as well as the values of 4.278 and 2.994 obtained using k-means-SVR(support vector regression)method.The other experiment is conducted on stock data froma public data set.The proposed method achieved an average RMSE and MAE of 0.836 and 0.696,lower than the respective values of 1.019 and 0.844 obtained using the ARIMA method,as well as the values of 1.350 and 1.172 obtained using the k-means-SVR method.
基金The study was approved by the ethics committee of the First Affiliated Hospital of Chongqing Medical University(2022-K205),this study was conducted in accordance with the World Medical Association Declaration of Helsinki as well。
文摘BACKGROUND Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer,the prognostic value of hematocrit for colorectal cancer(CRC)patients has not been determined.The prognostic value of red blood cell distribution width(RDW)for CRC patients was controversial.AIM To investigate the impact of RDW and hematocrit on the short-term outcomes and long-term prognosis of CRC patients who underwent radical surgery.METHODS Patients who were diagnosed with CRC and underwent radical CRC resection between January 2011 and January 2020 at a single clinical center were included.The short-term outcomes,overall survival(OS)and disease-free survival(DFS)were compared among the different groups.Cox analysis was also conducted to identify independent risk factors for OS and DFS.RESULTS There were 4258 CRC patients who underwent radical surgery included in our study.A total of 1573 patients were in the lower RDW group and 2685 patients were in the higher RDW group.There were 2166 and 2092 patients in the higher hematocrit group and lower hematocrit group,respectively.Patients in the higher RDW group had more intraoperative blood loss(P<0.01)and more overall complications(P<0.01)than did those in the lower RDW group.Similarly,patients in the lower hematocrit group had more intraoperative blood loss(P=0.012),longer hospital stay(P=0.016)and overall complications(P<0.01)than did those in the higher hematocrit group.The higher RDW group had a worse OS and DFS than did the lower RDW group for tumor node metastasis(TNM)stage I(OS,P<0.05;DFS,P=0.001)and stage II(OS,P=0.004;DFS,P=0.01)than the lower RDW group;the lower hematocrit group had worse OS and DFS for TNM stage II(OS,P<0.05;DFS,P=0.001)and stage III(OS,P=0.001;DFS,P=0.001)than did the higher hematocrit group.Preoperative hematocrit was an independent risk factor for OS[P=0.017,hazard ratio(HR)=1.256,95%confidence interval(CI):1.041-1.515]and DFS(P=0.035,HR=1.194,95%CI:1.013-1.408).CONCLUSION A higher preoperative RDW and lower hematocrit were associated with more postoperative complications.However,only hematocrit was an independent risk factor for OS and DFS in CRC patients who underwent radical surgery,while RDW was not.
基金supported by the National Natural Science Foundation of China,“State-owned Capital Participation and Financial Behavior of Private Enterprises:A Study from the Perspective of‘Balance’and‘Complementarity’of Multiple Major Shareholders”(Grant No.72202230).
文摘This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study finds that state-owned capital participation significantly reduces the debt financing costs of private enterprises and expands the scale of their debt financing.This conclusion remains valid after a series of endogeneity and robustness tests.Further analysis of the mechanism reveals that state-owned capital participation improves the debt financing of private enterprises through multiple channels:Enhancing their social reputation,mitigating the“statistical bias”they face,optimizing their information quality,and reducing the“shareholder-creditor”agency problems.This paper conceptualizes these benefits as the“complementary advantages of heterogeneous shareholders”.This not only constructs a theoretical framework for“reverse mixed-ownership reform”but also better narrates the Chinese story of“mixed-ownership reform”by adopting a more universally applicable theory of equity structure.Additionally,the paper supplements existing research on the macro-and meso-level relationship between the government and the market by exploring the government’s positive role at the micro-level.
基金supported by National Natural Science Foundation of China,China(No.42004016)HuBei Natural Science Fund,China(No.2020CFB329)+1 种基金HuNan Natural Science Fund,China(No.2023JJ60559,2023JJ60560)the State Key Laboratory of Geodesy and Earth’s Dynamics self-deployment project,China(No.S21L6101)。
文摘Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currently,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM prediction.Besides,the weighted LS+AR hybrid method performs well for PM short-term prediction.However,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR model.In this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid method.By using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid method.Compared to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,respectively.Besides,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.
文摘With the advancement of artificial intelligence,traffic forecasting is gaining more and more interest in optimizing route planning and enhancing service quality.Traffic volume is an influential parameter for planning and operating traffic structures.This study proposed an improved ensemble-based deep learning method to solve traffic volume prediction problems.A set of optimal hyperparameters is also applied for the suggested approach to improve the performance of the learning process.The fusion of these methodologies aims to harness ensemble empirical mode decomposition’s capacity to discern complex traffic patterns and long short-term memory’s proficiency in learning temporal relationships.Firstly,a dataset for automatic vehicle identification is obtained and utilized in the preprocessing stage of the ensemble empirical mode decomposition model.The second aspect involves predicting traffic volume using the long short-term memory algorithm.Next,the study employs a trial-and-error approach to select a set of optimal hyperparameters,including the lookback window,the number of neurons in the hidden layers,and the gradient descent optimization.Finally,the fusion of the obtained results leads to a final traffic volume prediction.The experimental results show that the proposed method outperforms other benchmarks regarding various evaluation measures,including mean absolute error,root mean squared error,mean absolute percentage error,and R-squared.The achieved R-squared value reaches an impressive 98%,while the other evaluation indices surpass the competing.These findings highlight the accuracy of traffic pattern prediction.Consequently,this offers promising prospects for enhancing transportation management systems and urban infrastructure planning.
基金funded by Liaoning Provincial Department of Science and Technology(2023JH2/101600058)。
文摘With the continuous advancement of China’s“peak carbon dioxide emissions and Carbon Neutrality”process,the proportion of wind power is increasing.In the current research,aiming at the problem that the forecasting model is outdated due to the continuous updating of wind power data,a short-term wind power forecasting algorithm based on Incremental Learning-Bagging Deep Hybrid Kernel Extreme Learning Machine(IL-Bagging-DHKELM)error affinity propagation cluster analysis is proposed.The algorithm effectively combines deep hybrid kernel extreme learning machine(DHKELM)with incremental learning(IL).Firstly,an initial wind power prediction model is trained using the Bagging-DHKELM model.Secondly,Euclidean morphological distance affinity propagation AP clustering algorithm is used to cluster and analyze the prediction error of wind power obtained from the initial training model.Finally,the correlation between wind power prediction errors and Numerical Weather Prediction(NWP)data is introduced as incremental updates to the initial wind power prediction model.During the incremental learning process,multiple error performance indicators are used to measure the overall model performance,thereby enabling incremental updates of wind power models.Practical examples show the method proposed in this article reduces the root mean square error of the initial model by 1.9 percentage points,indicating that this method can be better adapted to the current scenario of the continuous increase in wind power penetration rate.The accuracy and precision of wind power generation prediction are effectively improved through the method.
基金The research is supported by the National Natural Science Foundation of China (Grant no. 71172181 and 71302155), and the Beijing Higher Education Young Elite Teacher Project.
文摘This study observes and explores a puzzle in Chinese firms whereby both cash holdings and short-term debt simultaneously account for more than 20% of total assets for at least two consecutive years over the sample period. This phenomenon conflicts with the principle of corporate value maximization, and is not clearly explained by the classical theories in corporate finance. Based on the implications in the extant literature and discussions of institutional constraints of the transition economy in China, this paper develops four hypotheses that are involved with agency conflicts between the largest shareholders and creditors and the formation of this puzzling financial structure. The empirical analyses suggest that the largest shareholders with tunneling motives seek to hold more cash to serve their private interests and/or the consequent operational deficit of the listed corporations. To the ends, these corporations tend to manage the timing of short term debt financing to increase cash reserves temporarily at the end of year. Essentially, greater cash holdings on the balance sheet of these corporations related with the puzzle become a misleading signal for potential creditors, possibly contributing to the refinancing of short-term debt of these listed firms for the following year. Hence, the puzzling financial structure is connected with the timing of debt financing and adverse selection of creditors. This study enriches the stream of literature on cash holdings and debt maturity, and provides new evidence on the impact of agency problems of the largest shareholders on the association between cash holdings and debt maturity in the context of a transition economy.
基金funded by the National Natural Science Foundation of China (41807285)。
文摘The numerical simulation and slope stability prediction are the focus of slope disaster research.Recently,machine learning models are commonly used in the slope stability prediction.However,these machine learning models have some problems,such as poor nonlinear performance,local optimum and incomplete factors feature extraction.These issues can affect the accuracy of slope stability prediction.Therefore,a deep learning algorithm called Long short-term memory(LSTM)has been innovatively proposed to predict slope stability.Taking the Ganzhou City in China as the study area,the landslide inventory and their characteristics of geotechnical parameters,slope height and slope angle are analyzed.Based on these characteristics,typical soil slopes are constructed using the Geo-Studio software.Five control factors affecting slope stability,including slope height,slope angle,internal friction angle,cohesion and volumetric weight,are selected to form different slope and construct model input variables.Then,the limit equilibrium method is used to calculate the stability coefficients of these typical soil slopes under different control factors.Each slope stability coefficient and its corresponding control factors is a slope sample.As a result,a total of 2160 training samples and 450 testing samples are constructed.These sample sets are imported into LSTM for modelling and compared with the support vector machine(SVM),random forest(RF)and convo-lutional neural network(CNN).The results show that the LSTM overcomes the problem that the commonly used machine learning models have difficulty extracting global features.Furthermore,LSTM has a better prediction performance for slope stability compared to SVM,RF and CNN models.
基金the Project of the Central Government Guiding Local Science and Technology under Grant Number ZYYD2022B18the Institutional Ethics Committee of Affiliated Cancer Hospital of Xinjiang Medical University(No.K-2019001).
文摘Background:This study was designed to investigate the feasibility of tumor-infiltrating immune cells with different phenotypic characteristics for predicting short-term clinical responses in patients with locally advanced cervical cancer(LACC).Methods:Thirty-four patients who received concurrent chemoradiotherapy and twenty-one patients who merely underwent radiotherapy were enrolled in this study.We retrospectively analyzed the T cell markers(i.e.,CD3,CD4,CD8),memory markers(i.e.,CD45,CCR7),and differentiation markers(i.e.,CD27)in the peripheral blood and tumor tissues of patients with LACC before treatment based on flow cytometry.We also analyzed the relationship of T cell subsets between peripheral blood and tumor tissues,and their correlation with complete response or partial response.Results:The percentage of central memory CD8^(+)TCM(CD8^(+)CD45RA^(−)CD27^(+)CCR7^(+))cells in LACC patients was significantly lower than that of the control group.The percentage of CD8^(+)TN in the peripheral blood of LACC patients was significantly higher than that of tumor tissues.CD8^(+)TEM in the peripheral blood was significantly lower than that of tumor tissues.The percentage of CD8^(+)TN and CD8^(+)TCM in human papillomavirus(HPV)positive samples was significantly higher than that of HPV-negative samples.Similarly,the percentage of CD8^(+)TCM in tumor tissues was significantly higher in cancer tissue samples with lymph nodes compared with those without.Conclusion:A higher proportion of CD4^(+)TCM and a lower proportion of CD8^(+)TN in the tumor microenvironment of LACC may contribute to the therapy response prediction.
基金support provided in part by the National Key Research and Development Program of China (No.2020YFB1005804)in part by the National Natural Science Foundation of China under Grant 61632009+1 种基金in part by the High-Level Talents Program of Higher Education in Guangdong Province under Grant 2016ZJ01in part by the NCRA-017,NUST,Islamabad.
文摘Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy transactions.STLF ranges from an hour ahead prediction to a day ahead prediction. Variouselectric load forecasting methods have been used in literature for electricitygeneration planning to meet future load demand. A perfect balance regardinggeneration and utilization is still lacking to avoid extra generation and misusageof electric load. Therefore, this paper utilizes Levenberg–Marquardt(LM) based Artificial Neural Network (ANN) technique to forecast theshort-term electricity load for smart grids in a much better, more precise,and more accurate manner. For proper load forecasting, we take the mostcritical weather parameters along with historical load data in the form of timeseries grouped into seasons, i.e., winter and summer. Further, the presentedmodel deals with each season’s load data by splitting it into weekdays andweekends. The historical load data of three years have been used to forecastweek-ahead and day-ahead load demand after every thirty minutes makingload forecast for a very short period. The proposed model is optimized usingthe Levenberg-Marquardt backpropagation algorithm to achieve results withcomparable statistics. Mean Absolute Percent Error (MAPE), Root MeanSquared Error (RMSE), R2, and R are used to evaluate the model. Comparedwith other recent machine learning-based mechanisms, our model presentsthe best experimental results with MAPE and R2 scores of 1.3 and 0.99,respectively. The results prove that the proposed LM-based ANN modelperforms much better in accuracy and has the lowest error rates as comparedto existing work.
文摘BACKGROUND Obesity is a state in which excess heat is converted into excess fat,which accumulates in the body and may cause damage to multiple organs of the circulatory,endocrine,and digestive systems.Studies have shown that the accumulation of abdominal fat and mesenteric fat hypertrophy in patients with obesity makes laparoscopic surgery highly difficult,which is not conducive to operation and affects patient prognosis.However,there is still controversy regarding these conclusions.AIM To explore the relationship between body mass index(BMI)and short-term prognosis after surgery for colorectal cancer.METHODS PubMed,Embase,Ovid,Web of Science,CNKI,and China Biology Medicine Disc databases were searched to obtain relevant articles on this topic.After the articles were screened according to the inclusion and exclusion criteria and the risk of literature bias was assessed using the Newcastle-Ottawa Scale,the prognostic indicators were combined and analyzed.RESULTS A total of 16 articles were included for quantitative analysis,and 15588 patients undergoing colorectal cancer surgery were included in the study,including 3775 patients with obesity and 11813 patients without obesity.Among them,12 articles used BMI≥30 kg/m^(2)and 4 articles used BMI≥25 kg/m^(2)for the definition of obesity.Four patients underwent robotic colorectal surgery,whereas 12 underwent conventional laparoscopic colorectal resection.The quality of the literature was good.Meta-combined analysis showed that the overall complication rate of patients with obesity after surgery was higher than that of patients without obesity[OR=1.35,95%CI:1.23-1.48,Z=6.25,P<0.0001].The incidence of anastomotic leak after surgery in patients with obesity was not significantly different from that in patients without obesity[OR=0.99,95%CI:0.70-1.41),Z=-0.06,P=0.956].The incidence of surgical site infection(SSI)after surgery in patients with obesity was higher than that in patients without obesity[OR=1.43,95%CI:1.16-1.78,Z=3.31,P<0.001].The incidence of reoperation in patients with obesity after surgery was higher than that in patients without obesity;however,the difference was not statistically significant[OR=1.15,95%CI:0.92-1.45,Z=1.23,P=0.23];Patients with obesity had lower mortality after surgery than patients without obesity;however,the difference was not statistically significant[OR=0.61,95%CI:0.35-1.06,Z=-1.75,P=0.08].Subgroup analysis revealed that the geographical location of the institute was one of the sources of heterogeneity.Robot-assisted surgery was not significantly different from traditional laparoscopic resection in terms of the incidence of complications.CONCLUSION Obesity increases the overall complication and SSI rates of patients undergoing colorectal cancer surgery but has no influence on the incidence of anastomotic leak,reoperation rate,and short-term mortality rate.
基金supported by Science and Technology Project of State Grid Shandong Electric Power Company(52062622000R,Research on Aggregation and Regulation Technology of Regional Integrated Energy System).
文摘Wind power prediction is very important for the economic dispatching of power systems containing wind power.In this work,a novel short-term wind power prediction method based on improved complete ensemble empirical mode decomposition with adaptive noise(ICEEMDAN)and(long short-term memory)LSTM neural network is proposed and studied.First,the original data is prepossessed including removing outliers and filling in the gaps.Then,the random forest algorithm is used to sort the importance of each meteorological factor and determine the input climate characteristics of the forecast model.In addition,this study conducts seasonal classification of the annual data where ICEEMDAN is adopted to divide the original wind power sequence into numerous modal components according to different seasons.On this basis,sample entropy is used to calculate the complexity of each component and reconstruct them into trend components,oscillation components,and random components.Then,these three components are input into the LSTM neural network,respectively.Combined with the predicted values of the three components,the overall power prediction results are obtained.The simulation shows that ICEEMDAN-SE-LSTM achieves higher prediction accuracy ranging from 1.57%to 9.46%than other traditional models,which indicates the reliability and effectiveness of the proposed method for power prediction.
基金supported by grants from Key laboratory of Ecology and Environment in Minority Area,National Ethnic Affairs Commission(KLEEMA202207)the Graduate Research and Practice Projects of Minzu University of China(BZKY2022042).
文摘Night lighting has been shown to affect wild animals.To date,the effects of night lighting on the metabolic homeostasis of birds that spend short time in urban environments remain unclear.Using model bird species Zebra Finch(Taeniopygia guttata),we investigated the effects of short-term night lighting on liver transcriptome,blood glucose,triglyceride,and thyroxine(T4 and T3)levels in birds exposed to two different night lighting duration periods(three days and six days).After three days of night lighting exposure,the expression of genes involved in fat synthesis in the liver was upregulated while the expression of genes involved in fatty acid oxidation and triglyceride decomposition was downregulated.There was also a reduction in blood triglyceride,glucose,and T3 concentrations.However,after six days of night lighting,the expression of genes associated with fatty acid decomposition and hyperglycemia in the liver was upregulated,while the expression of genes involved in fat synthesis was downregulated.Simultaneously,blood glucose levels and T3 concentration increased.These findings indicate that short-term exposure to night lighting can disrupt the lipid and glucose metabolism of small passerine birds,and longer stopovers in urban area with intense night lighting may cause birds to consume more lipid energy.
基金supported by the China National Natural Science Foundation(52177082)China National Key R&D Program(2020YFC0827001)Science and Technology Project of Jilin Electric Power Co.,Ltd(2020JBGS-03).
文摘This study proposes a two-stage photovoltaic(PV)voltage control strategy for centralized control that ignores short-term load fluctuations.In the first stage,a deterministic power flow model optimizes the 15-minute active cycle of the inverter and reactive outputs to reduce network loss and light rejection.In the second stage,the local control stabilizes the fluctuations and tracks the system state of the first stage.The uncertain interval model establishes a chance constraint model for the inverter voltage-reactive power local control.Second-order cone optimization and sensitivity theories were employed to solve the models.The effectiveness of the model was confirmed using a modified IEEE 33 bus example.The intraday control outcome for distributed power generation considering the effects of fluctuation uncertainty,PV penetration rate,and inverter capacity is analyzed.
文摘A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively used and still have considerable potential. In recent years, methods based on deep neural networks have made significant breakthroughs, and fault diagnosis methods for industrial processes based on deep learning have attracted considerable research attention. Therefore, we propose a fusion deeplearning algorithm based on a fully convolutional neural network(FCN) to extract features and build models to correctly diagnose all types of faults. We use long short-term memory(LSTM) units to expand our proposed FCN so that our proposed deep learning model can better extract the time-domain features of chemical process data. We also introduce the attention mechanism into the model, aimed at highlighting the importance of features, which is significant for the fault diagnosis of chemical processes with many features. When applied to the benchmark Tennessee Eastman process, our proposed model exhibits impressive performance, demonstrating the effectiveness of the attention-based LSTM FCN in chemical process fault diagnosis.
基金supported by the National Natural Science Foundation of China under Grant 51777193.
文摘An improved fuzzy time series algorithmbased on clustering is designed in this paper.The algorithm is successfully applied to short-term load forecasting in the distribution stations.Firstly,the K-means clustering method is used to cluster the data,and the midpoint of two adjacent clustering centers is taken as the dividing point of domain division.On this basis,the data is fuzzed to form a fuzzy time series.Secondly,a high-order fuzzy relation with multiple antecedents is established according to the main measurement indexes of power load,which is used to predict the short-term trend change of load in the distribution stations.Matlab/Simulink simulation results show that the load forecasting errors of the typical fuzzy time series on the time scale of one day and one week are[−50,20]and[−50,30],while the load forecasting errors of the improved fuzzy time series on the time scale of one day and one week are[−20,15]and[−20,25].It shows that the fuzzy time series algorithm improved by clustering improves the prediction accuracy and can effectively predict the short-term load trend of distribution stations.