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Narrative nursing for negative emotions in patients with acute pancreatitis:Based on model construction and application
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作者 Ling-Jun Zhou Juan Wu +4 位作者 Wen-Jie Huang Ai-Wu Shen Yu-Ping Yin Hai-Li Sun Yu-Ting Yuan 《World Journal of Psychiatry》 SCIE 2024年第11期1631-1640,共10页
BACKGROUND Acute pancreatitis(AP),as a common acute abdomen disease,has a high incidence rate worldwide and is often accompanied by severe complications.Negative emotions lead to increased secretion of stress hormones... BACKGROUND Acute pancreatitis(AP),as a common acute abdomen disease,has a high incidence rate worldwide and is often accompanied by severe complications.Negative emotions lead to increased secretion of stress hormones,elevated blood sugar levels,and enhanced insulin resistance,which in turn increases the risk of AP and significantly affects the patient's quality of life.Therefore,exploring the intervention effects of narrative nursing programs on the negative emotions of patients with AP is not only helpful in alleviating psychological stress and improving quality of life but also has significant implications for improving disease outcomes and prognosis.AIM To construct a narrative nursing model for negative emotions in patients with AP and verify its efficacy in application.METHODS Through Delphi expert consultation,a narrative nursing model for negative emotions in patients with AP was constructed.A non-randomized quasi-experimental study design was used in this study.A total of 92 patients with AP with negative emotions admitted to a tertiary hospital in Nantong City of Jiangsu Province,China from September 2022 to August 2023 were recruited by convenience sampling,among whom 46 patients admitted from September 2022 to February 2023 were included in the observation group,and 46 patients from March to August 2023 were selected as control group.The observation group received narrative nursing plan,while the control group was given with routine nursing.Self-rating anxiety scale(SAS),self-rating depression scale(SDS),positive and negative affect scale(PANAS),caring behavior scale,patient satisfaction scale and 36-item short form health survey questionnaire(SF-36)were used to evaluate their emotions,satisfaction and caring behaviors in the two groups on the day of discharge,1-and 3-month following discharge.RESULTS According to the inclusion and exclusion criteria,a total of 45 cases in the intervention group and 44 cases in the control group eventually recruited and completed in the study.On the day of discharge,the intervention group showed significantly lower scores of SAS,SDS and negative emotion(28.57±4.52 vs 17.4±4.44,P<0.001),whereas evidently higher outcomes in the positive emotion score,Caring behavior scale score and satisfaction score compared to the control group(P<0.05).Repeated measurement analysis of variance showed that significant between-group differences were found in time effect,inter-group effect and interaction effect of SAS and PANAS scores as well as in time effect and inter-group effect of SF-36 scores(P<0.05);the SF-36 scores of two groups at 3 months after discharge were higher than those at 1 month after discharge(P<0.05).CONCLUSION The application of narrative nursing protocols has demonstrated significant effectiveness in alleviating anxiety,ameliorating negative emotions,and enhancing satisfaction among patients with AP. 展开更多
关键词 Acute pancreatitis Negative emotions Narrative nursing model Adverse emotions Self-rating anxiety scale Selfrating depression scale
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Nursing model of midwifery and postural and psychological interventions:Impact on maternal and fetal outcomes and negative emotions of primiparas 被引量:1
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作者 Ping Gao Cai-Qiong Guo +1 位作者 Ma-Yu Chen Hui-Ping Zhuang 《World Journal of Psychiatry》 SCIE 2023年第8期543-550,共8页
BACKGROUND Primiparas are usually at high risk of experiencing perinatal depression,which may cause prolonged labor,increased blood loss,and intensified pain,affecting maternal and fetal outcomes.Therefore,interventio... BACKGROUND Primiparas are usually at high risk of experiencing perinatal depression,which may cause prolonged labor,increased blood loss,and intensified pain,affecting maternal and fetal outcomes.Therefore,interventions are necessary to improve maternal and fetal outcomes and alleviate primiparas’negative emotions(NEs).AIM To discusses the impact of nursing responsibility in midwifery and postural and psychological interventions on maternal and fetal outcomes as well as primiparas’NEs.METHODS As participants,115 primiparas admitted to Quanzhou Maternity and Child Healthcare Hospital between May 2020 and May 2022 were selected.Among them,56 primiparas(control group,Con)were subjected to conventional midwifery and routine nursing.The remaining 59(research group,Res)were subjected to the nursing model of midwifery and postural and psychological interventions.Both groups were comparatively analyzed from the perspectives of delivery mode(cesarean,natural,or forceps-assisted),maternal and fetal outcomes(uterine inertia,postpartum hemorrhage,placental abruption,neonatal pulmonary injury,and neonatal asphyxia),NEs(Hamilton Anxiety/Depressionrating Scale,HAMA/HAMD),labor duration,and nursing satisfaction.RESULTS The Res exhibited a markedly higher natural delivery rate and nursing satisfaction than the Con.Additionally,the Res indicated a lower incidence of adverse events(e.g.,uterine inertia,postpartum hemorrhage,placental abruption,neonatal lung injury,and neonatal asphyxia)and shortened duration of various stages of labor.It also showed statistically lower post-interventional HAMA and HAMD scores than the Con and pre-interventional values.CONCLUSION The nursing model of midwifery and postural and psychological interventions increase the natural delivery rate and reduce the duration of each labor stage.These are also conducive to improving maternal and fetal outcomes and mitigating primiparas’NEs and thus deserve popularity in clinical practice. 展开更多
关键词 Nursing model of midwifery Postural intervention PRIMIPARA Maternal and fetal outcomes Negative emotions
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Film and Television Website Scores Authenticity Verification Based on the Emotional Analysis
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作者 Weiyu Tong 《Journal of Computer and Communications》 2024年第2期231-245,共15页
Sentiment analysis is a method to identify and understand the emotion in the text through NLP and text analysis. In the era of information technology, there is often a certain error between the comments on the movie w... Sentiment analysis is a method to identify and understand the emotion in the text through NLP and text analysis. In the era of information technology, there is often a certain error between the comments on the movie website and the actual score of the movie, and sentiment analysis technology provides a new way to solve this problem. In this paper, Python is used to obtain the movie review data from the Douban platform, and the model is constructed and trained by using naive Bayes and Bi-LSTM. According to the index, a better Bi-LSTM model is selected to classify the emotion of users’ movie reviews, and the classification results are scored according to the classification results, and compared with the real ratings on the website. According to the error of the final comparison results, the feasibility of this technology in the scoring direction of film reviews is being verified. By applying this technology, the phenomenon of film rating distortion in the information age can be prevented and the rights and interests of film and television works can be safeguarded. 展开更多
关键词 Bi-LSTM model Film Review emotion Analysis Naive Bayes PYTHON Data Crawl
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Model considering panic emotion and personality traits for crowd evacuation
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作者 孙华锴 陈长坤 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期321-336,共16页
Panic is a common emotion when pedestrians are in danger during the actual evacuation, which can affect pedestrians a lot and may lead to fatalities as people are crushed or trampled. However, the systematic studies a... Panic is a common emotion when pedestrians are in danger during the actual evacuation, which can affect pedestrians a lot and may lead to fatalities as people are crushed or trampled. However, the systematic studies and quantitative analysis of evacuation panic, such as panic behaviors, panic evolution, and the stress responses of pedestrians with different personality traits to panic emotion are still rare. Here, combined with the theories of OCEAN(openness, conscientiousness,extroversion, agreeableness, neuroticism) model and SIS(susceptible, infected, susceptible) model, an extended cellular automata model is established by the floor field method in order to investigate the dynamics of panic emotion in the crowd and dynamics of pedestrians affected by emotion. In the model, pedestrians are divided into stable pedestrians and sensitive pedestrians according to their different personality traits in response to emotion, and their emotional state can be normal or panic. Besides, emotion contagion, emotion decay, and the influence of emotion on pedestrian movement decision-making are also considered. The simulation results show that evacuation efficiency will be reduced, for panic pedestrians may act maladaptive behaviors, thereby making the crowd more chaotic. The results further suggest that improving pedestrian psychological ability and raising the standard of management can effectively increase evacuation efficiency. And it is necessary to reduce the panic level of group as soon as possible at the beginning of evacuation. We hope this research could provide a new method to analyze crowd evacuation in panic situations. 展开更多
关键词 panic emotion CA-SIS model crowd evacuation personality trait
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Construction of Psychological Adjustment Function Model of Music Education Based on Emotional Tendency Analysis
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作者 Bin Zhang 《International Journal of Mental Health Promotion》 2023年第5期655-671,共17页
In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education ... In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education is based on emotional tendency analysis of psychological adjustment function model.Design emotional tendency analysis of music education psychological adjustment function architecture,music teaching goal as psychological adjust-ment function architecture building orientation,music teaching content as a foundation for psychological adjust-ment function architecture and music teaching process as a psychological adjustment function architecture building,music teaching evaluation as the key of building key regulating function architecture,Establish a core literacy oriented evaluation system.Different evaluation methods were used to obtain the evaluation results.Four levels of psychological adjustment function model of music education are designed,and the psychological adjust-ment function of music education is put forward,thus completing the construction of psychological adjustment function model of music education.The experimental results show that the absolute value of the data acquisition error of the designed model is minimum,which is not more than 0.2.It is less affected by a bad coefficient and has good performance.It can quickly converge to the best state in the actual prediction process and has a strong con-vergence ability. 展开更多
关键词 emotional tendency analysis music education psychological adjustment functional model core literacy orientation
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Cascaded projection of Gaussian mixture model for emotion recognition in speech and ECG signals 被引量:1
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作者 黄程韦 吴迪 +5 位作者 张晓俊 肖仲喆 许宜申 季晶晶 陶智 赵力 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期320-326,共7页
A cascaded projection of the Gaussian mixture model algorithm is proposed.First,the marginal distribution of the Gaussian mixture model is computed for different feature dimensions, and a number of sub-classifiers are... A cascaded projection of the Gaussian mixture model algorithm is proposed.First,the marginal distribution of the Gaussian mixture model is computed for different feature dimensions, and a number of sub-classifiers are generated using the marginal distribution model.Each sub-classifier is based on different feature sets.The cascaded structure is adopted to fuse the sub-classifiers dynamically to achieve sample adaptation ability.Secondly,the effectiveness of the proposed algorithm is verified on electrocardiogram emotional signal and speech emotional signal.Emotional data including fidgetiness,happiness and sadness is collected by induction experiments.Finally,the emotion feature extraction method is discussed,including heart rate variability, the chaotic electrocardiogram feature and utterance level static feature.The emotional feature reduction methods are studied, including principle component analysis,sequential forward selection, the Fisher discriminant ratio and maximal information coefficient.The experimental results show that the proposed classification algorithm can effectively improve recognition accuracy in two different scenarios. 展开更多
关键词 Gaussian mixture model emotion recognition sample adaptation emotion inducing
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A Multi-Level Circulant Cross-Modal Transformer for Multimodal Speech Emotion Recognition 被引量:1
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作者 Peizhu Gong Jin Liu +3 位作者 Zhongdai Wu Bing Han YKenWang Huihua He 《Computers, Materials & Continua》 SCIE EI 2023年第2期4203-4220,共18页
Speech emotion recognition,as an important component of humancomputer interaction technology,has received increasing attention.Recent studies have treated emotion recognition of speech signals as a multimodal task,due... Speech emotion recognition,as an important component of humancomputer interaction technology,has received increasing attention.Recent studies have treated emotion recognition of speech signals as a multimodal task,due to its inclusion of the semantic features of two different modalities,i.e.,audio and text.However,existing methods often fail in effectively represent features and capture correlations.This paper presents a multi-level circulant cross-modal Transformer(MLCCT)formultimodal speech emotion recognition.The proposed model can be divided into three steps,feature extraction,interaction and fusion.Self-supervised embedding models are introduced for feature extraction,which give a more powerful representation of the original data than those using spectrograms or audio features such as Mel-frequency cepstral coefficients(MFCCs)and low-level descriptors(LLDs).In particular,MLCCT contains two types of feature interaction processes,where a bidirectional Long Short-term Memory(Bi-LSTM)with circulant interaction mechanism is proposed for low-level features,while a two-stream residual cross-modal Transformer block is appliedwhen high-level features are involved.Finally,we choose self-attention blocks for fusion and a fully connected layer to make predictions.To evaluate the performance of our proposed model,comprehensive experiments are conducted on three widely used benchmark datasets including IEMOCAP,MELD and CMU-MOSEI.The competitive results verify the effectiveness of our approach. 展开更多
关键词 Speech emotion recognition self-supervised embedding model cross-modal transformer self-attention
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Development and application of a two-dimensional water quality model for the Daqinghe River Mouth of the Dianchi Lake 被引量:12
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作者 CHEN Qiuwen TAN Kui +1 位作者 ZHU Chuanbao LI Ruonan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期313-318,共6页
Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi L... Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi Lake, China, a two-dimensional water quality model was developed in the research. The hydrodynamics module was numerically solved by the alternating direction iteration (ADI) method. The parameters of the water quality module were obtained through the in situ experiments and the laboratory analyses that were conducted from 2006 to 2007. The model was calibrated and verified by the observation data in 2007. Among the four modelled key variables, i.e., water level, COD (in CODcr), NH4+-N and PO43-P the minimum value of the coefficient of determination (COD) was 0.69, indicating the model performed reasonably well. The developed model was then applied to simulate the water quality changes at a downstream cross-section assuming that the designed restoration programs were implemented. According to the simulated results, the restoration programs could cut down the loads of COD and PO43-P about 15%. Such a load reduction, unfortunately, would have very little effect on the NH4^+-N removal. Moreover, the water quality at the outlet cross-section would be still in class V (3838-02), indicating more measures should be taken to further reduce the loads. The study demonstrated the capability of water quality models to support aquatic ecosystem restorations. 展开更多
关键词 two-dimensional water quality model parameter estimation restoration program evaluation Dianchi Lake
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Simulation of two-dimensional interior ballistics model of solid propellant electrothermal-chem ical launch with discharge rod plasma generator 被引量:6
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作者 Yan-jie Ni Yong Jin +3 位作者 Niankai Cheng Chun-xia Yang Hai-yuan Li Bao-ming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第4期249-256,共8页
Instead of the capillary plasma generator(CPG),a discharge rod plasma generator(DRPG)is used in the30 mm electrothermal-chemical(ETC)gun to improve the ignition uniformity of the solid propellant.An axisymmetric two-d... Instead of the capillary plasma generator(CPG),a discharge rod plasma generator(DRPG)is used in the30 mm electrothermal-chemical(ETC)gun to improve the ignition uniformity of the solid propellant.An axisymmetric two-dimensional interior ballistics model of the solid propellant ETC gun(2D-IB-SPETCG)is presented to describe the process of the ETC launch.Both calculated pressure and projectile muzzle velocity accord well with the experimental results.The feasibility of the 2D-IB-SPETCG model is proved.Depending on the experimental data and initial parameters,detailed distribution of the ballistics parameters can be simulated.With the distribution of pressure and temperature of the gas phase and the propellant,the influence of plasma during the ignition process can be analyzed.Because of the radial flowing plasma,the propellant in the area of the DRPG is ignited within 0.01 ms,while all propellant in the chamber is ignited within 0.09 ms.The radial ignition delay time is much less than the axial delay time.During the ignition process,the radial pressure difference is less than 5 MPa at the place 0.025 m away from the breech.The radial ignition uniformity is proved.The temperature of the gas increases from several thousand K(conventional ignition)to several ten thousand K(plasma ignition).Compare the distribution of the density and temperature of the gas,we know that low density and high temperature gas appears near the exits of the DRPG,while high density and low temperature gas appears at the wall near the breech.The simulation of the 2D-IB-SPETCG model is an effective way to investigate the interior ballistics process of the ETC launch.The 2D-IB-SPETC model can be used for prediction and improvement of experiments. 展开更多
关键词 Electrothermal-chemical LAUNCH Interior BALLISTICS SIMULATION Two-phase flow two-dimensional model
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Performance assessment of two-dimensional hydraulic models for generation of flood inundation maps in mountain river basins 被引量:3
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作者 Juan Pinos Luis Timbe 《Water Science and Engineering》 EI CAS CSCD 2019年第1期11-18,共8页
Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presen... Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty. 展开更多
关键词 two-dimensional HYDRAULIC models FLOOD modeling FLOOD extent Water surface ELEVATION High MOUNTAIN RIVER Ecuador
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Artificial emotional model based on finite state machine 被引量:4
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作者 孟庆梅 吴伟国 《Journal of Central South University of Technology》 EI 2008年第5期694-699,共6页
According to the basic emotional theory, the artificial emotional model based on the finite state machine(FSM) was presented. In finite state machine model of emotion, the emotional space included the basic emotiona... According to the basic emotional theory, the artificial emotional model based on the finite state machine(FSM) was presented. In finite state machine model of emotion, the emotional space included the basic emotional space and the multiple emotional spaces. The emotion-switching diagram was defined and transition fimction was developed using Markov chain and linear interpolation algorithm. The simulation model was built using Stateflow toolbox and Simulink toolbox based on the Matlab platform. And the model included three subsystems: the input one, the emotion one and the behavior one. In the emotional subsystem, the responses of different personalities to the external stimuli were described by defining personal space. This model takes states from an emotional space and updates its state depending on its current state and a state of its input (also a state-emotion). The simulation model realizes the process of switching the emotion from the neutral state to other basic emotions. The simulation result is proved to correspond to emotion-switching law of human beings. 展开更多
关键词 finite state machine artificial emotion model Markov chain SIMULATION
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EEG Emotion Recognition Using an Attention Mechanism Based on an Optimized Hybrid Model 被引量:2
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作者 Huiping Jiang Demeng Wu +2 位作者 Xingqun Tang Zhongjie Li Wenbo Wu 《Computers, Materials & Continua》 SCIE EI 2022年第11期2697-2712,共16页
Emotions serve various functions.The traditional emotion recognition methods are based primarily on readily accessible facial expressions,gestures,and voice signals.However,it is often challenging to ensure that these... Emotions serve various functions.The traditional emotion recognition methods are based primarily on readily accessible facial expressions,gestures,and voice signals.However,it is often challenging to ensure that these non-physical signals are valid and reliable in practical applications.Electroencephalogram(EEG)signals are more successful than other signal recognition methods in recognizing these characteristics in real-time since they are difficult to camouflage.Although EEG signals are commonly used in current emotional recognition research,the accuracy is low when using traditional methods.Therefore,this study presented an optimized hybrid pattern with an attention mechanism(FFT_CLA)for EEG emotional recognition.First,the EEG signal was processed via the fast fourier transform(FFT),after which the convolutional neural network(CNN),long short-term memory(LSTM),and CNN-LSTM-attention(CLA)methods were used to extract and classify the EEG features.Finally,the experiments compared and analyzed the recognition results obtained via three DEAP dataset models,namely FFT_CNN,FFT_LSTM,and FFT_CLA.The final experimental results indicated that the recognition rates of the FFT_CNN,FFT_LSTM,and FFT_CLA models within the DEAP dataset were 87.39%,88.30%,and 92.38%,respectively.The FFT_CLA model improved the accuracy of EEG emotion recognition and used the attention mechanism to address the often-ignored importance of different channels and samples when extracting EEG features. 展开更多
关键词 emotion recognition EEG signal optimized hybrid model attention mechanism
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HIGH RESOLUTION PARAMETRIC MODELLING FOR TWO-DIMENSIONAL RADAR TARGET USING PRONY ALGORITHM 被引量:2
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作者 Wang Jun (Institute of Electronic Engineering, Chinese Academy of Engineering and Physics, Mianyang 621900) 《Journal of Electronics(China)》 2000年第1期38-45,共8页
On the conditions of low-resolution radar, a parametric model for two-dimensional radar target is described here according to the theory of electromagnetic scattering and the geometrical theory of diffraction. A high ... On the conditions of low-resolution radar, a parametric model for two-dimensional radar target is described here according to the theory of electromagnetic scattering and the geometrical theory of diffraction. A high resolution estimation algorithm to extract the model parameters is also developed by building the relation of the scattering model and Prony model. The analysis of Cramer-Rao bound and simulation show that the method here has better statistical performance. The simulated analysis also indicates that the accurate extraction of the diffraction coefficient of scattering center is restricted by signal to noise ratio, radar center frequency and radar bandwidth. 展开更多
关键词 two-dimensional RADAR SCATTERING center attributes PARAMETRIC modelling PRONY algorithm RESOLUTION
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A Numerical Algorithm Based on Quadratic Finite Element for Two-Dimensional Nonlinear Time Fractional Thermal Diffusion Model 被引量:3
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作者 Yanlong Zhang Baoli Yin +2 位作者 Yue Cao Yang Liu Hong Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第3期1081-1098,共18页
In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-d... In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-dimensional nonlinear time fractional thermal diffusion model.The time Caputo fractional derivative is approximated by using the L2-1formula,the first-order derivative and nonlinear term are discretized by some second-order approximation formulas,and the quadratic finite element is used to approximate the spatial direction.The error accuracy O(h3+t2)is obtained,which is verified by the numerical results. 展开更多
关键词 Quadratic finite element two-dimensional nonlinear time fractional thermal diffusion model L2-1formula.
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Global Two-Dimensional Chemistry Model and Simulation of Atmospheric Chemical Composition 被引量:1
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作者 张仁健 王明星 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第1期72-82,共11页
A global two-dimensional zonally averaged chemistry model is developed to study the chemi-cal composition of atmosphere. The region of the model is from 90°S to 90°N and from the ground to the altitude of 20... A global two-dimensional zonally averaged chemistry model is developed to study the chemi-cal composition of atmosphere. The region of the model is from 90°S to 90°N and from the ground to the altitude of 20 km with a resolution of 5° x 1 km. The wind field is residual circulation calcu-lated from diabatic rate. 34 species and 104 chemical and photochemical reactions are considered in the model. The sources of CH4, CO and NOx, which are divided into seasonal sources and non-seasonal sources, are parameterized as a function of latitude and time. The chemical composi-tion of atmosphere was simulated with emission level of CH4, CO and NOx in 1990. The results are compared with observations and other model results, showing that the model is successful to simu-late the atmospheric chemical composition and distribution of CH4. Key words Global two-dimensional chemistry model - Atmospheric composition - Emission This work was supported by the State Key Program for basic research “ Climate Dynamics and Cli-mate Prediction Theory” (Pandeng-yu-21).The authors would like to express their thanks to the National Oceanic and Atmospheric Administration (NOAA), Climate Monitoring and Diagnostics Laboratory (CMDL), Carbon Cycle Group for providing the observational data of CO and CH4. 展开更多
关键词 Global two-dimensional chemistry model Atmospheric composition EMISSION
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Comprehensive two-dimensional river ice model based on boundary-fitted coordinate transformation method 被引量:1
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作者 Ze-yu MAO Jing YUAN +2 位作者 Jun BAO Xiao-fan PENG Guo-qiang TANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期90-105,共16页
River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal pro... River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal processes, and they are also influenced by weather and hydrologic conditions. Because natural rivers are serpentine, with bends, narrows, and straight reaches, the commonly-used one-dimensional river ice models and two-dimensional models based on the rectangular Cartesian coordinates are incapable of simulating the physical phenomena accurately. In order to accurately simulate the complicated river geometry and overcome the difficulties of numerical simulation resulting from both complex boundaries and differences between length and width scales, a two-dimensional river ice numerical model based on a boundary-fitted coordinate transformation method was developed. The presented model considers the influence of the frazil ice accumulation under ice cover and the shape of the leading edge of ice cover during the freezing process. The model is capable of determining the velocity field, the distribution of water temperature, the concentration distribution of frazil ice, the transport of floating ice, the progression, stability, and thawing of ice cover, and the transport, accumulation, and erosion of ice under ice cover. A MacCormack scheme was used to solve the equations numerically. The model was validated with field observations from the Hequ Reach of the Yellow River. Comparison of simulation results with field data indicates that the model is capable of simulating the river ice process with high accuracy. 展开更多
关键词 two-dimensional river ice numerical model boundary-fitted coordinate technology river ice process freeze-up MacCormack scheme natural river
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Short-Term Mindfulness Intervention on Adolescents’ Negative Emotion under Global Pandemic
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作者 Yue Yuan Aibao Zhou +3 位作者 Tinghao Tang Manying Kang Haiyan Zhao Zhi Wang 《International Journal of Mental Health Promotion》 2023年第4期563-577,共15页
Objective:In this research,we tried to explore how short-term mindfulness(STM)intervention affects adoles-cents’anxiety,depression,and negative and positive emotion during the COVID-19 pandemic.Design:10 classes were... Objective:In this research,we tried to explore how short-term mindfulness(STM)intervention affects adoles-cents’anxiety,depression,and negative and positive emotion during the COVID-19 pandemic.Design:10 classes were divided into experiment groups(5 classes;n=238)and control(5 classes;n=244)randomly.Hospital Anxi-ety and Depression Scale(HADS)and Positive and Negative Affect Schedule(PANAS)were used to measure par-ticipants’dependent variables.In the experiment group,we conducted STM practice interventions every morning in theirfirst class from March to November 2020.No interventions were conducted in the control group.Methods:Paired-sample t-tests were used to identify if a significant difference exists between every time point of the experimental and control groups.Repeated ANOVA and Growth Mixture Model(GMM)were used to analyze the tendency of positive and negative emotions,anxiety,and depression in the experimental group.Results and Conclusions:(1)With the intervention of STM,there was a significant decrease in negative emotions and an increase in positive emotions in the experimental group,whereas there were non-significant differences in the control group.(2)To explore the heterogeneity trajectories of dependent variables,we built a GMM and found there were two latent growth classes in the trajectories.(3)The results of the models showed their trajec-tories were downward,which meant that the levels of anxiety,depression,and negative emotions of participants decreased during the STM training period.Nonetheless,the score of positive affect showed upward in three loops of intervention,which indicated that the level of the participants’positive affect increased through the STM inter-vention.(4)This research indicated that STM should be given increasing consideration to enhance mental health during the worldwide outbreak of COVID-19. 展开更多
关键词 Negative and positive emotional anxiety depression short-term mindfulness randomized controlled trial growth mixture model global pandemic of each of the two class groups illustrated in Fig.4B which showed obvious differences between the two class groups.
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Numerical modeling of blast-induced rock fragmentation in deep mining with 3D and 2D FEM method approaches
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作者 MichałKucewicz MazurkiewiczŁukasz +4 位作者 PawełBaranowski Jerzy Małachowski Krzysztof Fuławka Piotr Mertuszka Marcin Szumny 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4532-4553,共22页
To optimize the excavation of rock using underground blasting techniques,a reliable and simplified approach for modeling rock fragmentation is desired.This paper presents a multistep experimentalnumerical methodology ... To optimize the excavation of rock using underground blasting techniques,a reliable and simplified approach for modeling rock fragmentation is desired.This paper presents a multistep experimentalnumerical methodology for simplifying the three-dimensional(3D)to two-dimensional(2D)quasiplane-strain problem and reducing computational costs by more than 100-fold.First,in situ tests were conducted involving single-hole and free-face blasting of a dolomite rock mass in a 1050-m-deep mine.The results were validated by laser scanning.The craters were then compared with four analytical models to calculate the radius of the crushing zone.Next,a full 3D model for single-hole blasting was prepared and validated by simulating the crack length and the radius of the crushing zone.Based on the stable crack propagation zones observed in the 3D model and experiments,a 2D model was prepared.The properties of the high explosive(HE)were slightly reduced to match the shape and number of radial cracks and crushing zone radius between the 3D and 2D models.The final methodology was used to reproduce various cut-hole blasting scenarios and observe the effects of residual cracks in the rock mass on further fragmentation.The presence of preexisting cracks was found to be crucial for fragmentation,particularly when the borehole was situated near a free rock face.Finally,an optimization study was performed to determine the possibility of losing rock continuity at different positions within the well in relation to the free rock face. 展开更多
关键词 Dolomite rock two-dimensional(2D)rock modeling Rock fragmentation Cut-hole blasting
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DETERMINATION OF PARAMETERS IN A TWO-DIMENSIONAL MODEL FOR FIXED-BED ADSORBERS
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作者 韩振为 周明 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第1期43-51,共9页
A new method is proposed for the determination of the parameters in a two-dimensionalmodel which characterizes the properties of axial and radial mixing and mass transport in afixed-bed adsorber.Parameter estimation f... A new method is proposed for the determination of the parameters in a two-dimensionalmodel which characterizes the properties of axial and radial mixing and mass transport in afixed-bed adsorber.Parameter estimation for the model is carried out with methane-air-5A molecularsieve in a bed under the condition of step injection of tracer from a point on the main axis of thebed by the curve fitting method in the time domain. 展开更多
关键词 ADSORPTION FIXED-BED two-dimensional model PARAMETER ESTIMATION
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Two-dimensional hydrodynamic robust numerical model of soil erosion based on slopes and river basins
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作者 KANG Yongde HUANG Miansong +2 位作者 HOU Jingming TONG Yu PAN Zhanpeng 《Journal of Arid Land》 SCIE CSCD 2021年第10期995-1014,共20页
Erosion is an important issue in soil science and is related to many environmental problems,such as soil erosion and sediment transport.Establishing a simulation model suitable for soil erosion prediction is of great ... Erosion is an important issue in soil science and is related to many environmental problems,such as soil erosion and sediment transport.Establishing a simulation model suitable for soil erosion prediction is of great significance not only to accurately predict the process of soil separation by runoff,but also improve the physical model of soil erosion.In this study,we develop a graphic processing unit(GPU)-based numerical model that combines two-dimensional(2D)hydrodynamic and Green-Ampt(G-A)infiltration modelling to simulate soil erosion.A Godunov-type scheme on a uniform and structured square grid is then generated to solve the relevant shallow water equations(SWEs).The highlight of this study is the use of GPU-based acceleration technology to enable numerical models to simulate slope and watershed erosion in an efficient and high-resolution manner.The results show that the hydrodynamic model performs well in simulating soil erosion process.Soil erosion is studied by conducting calculation verification at the slope and basin scales.The first case involves simulating soil erosion process of a slope surface under indoor artificial rainfall conditions from 0 to 1000 s,and there is a good agreement between the simulated values and the measured values for the runoff velocity.The second case is a river basin experiment(Coquet River Basin)that involves watershed erosion.Simulations of the erosion depth change and erosion cumulative amount of the basin during a period of 1-40 h show an elevation difference of erosion at 0.5-3.0 m,especially during the period of 20-30 h.Nine cross sections in the basin are selected for simulation and the results reveal that the depth of erosion change value ranges from-0.86 to-2.79 m and the depth of deposition change value varies from 0.38 to 1.02 m.The findings indicate that the developed GPU-based hydrogeomorphological model can reproduce soil erosion processes.These results are valuable for rainfall runoff and soil erosion predictions on rilled hillslopes and river basins. 展开更多
关键词 soil erosion two-dimensional modelling rainfall runoff Green-Ampt model gully erosion
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