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Accelerated Sequential Deposition Reaction via Crystal Orientation Engineering for Low-Temperature,High-Efficiency Carbon-Electrode CsPbBr_(3) Solar Cells 被引量:1
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作者 Zeyang Zhang Weidong Zhu +10 位作者 Tianjiao Han Tianran Wang Wenming Chai Jiaduo Zhu He Xi Dazheng Chen Gang Lu Peng Dong Jincheng Zhang Chunfu Zhang Yue Hao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期168-175,共8页
Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation en... Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation engineering strategy of PbBr_(2)precursor film to accelerate its reaction with CsBr precursor during two-step sequential deposition of CsPbBr_(3)films.Such a novel strategy is proceeded by adding CsBr species into PbBr_(2)precursor,which can tailor the preferred crystal orientation of PbBr_(2)film from[020]into[031],with CsBr additive staying in the film as CsPb_(2)Br_(5)phase.Theoretical calculations show that the reaction energy barrier of(031)planes of PbBr_(2)with CsBr is lower about 2.28 eV than that of(O2O)planes.Therefore,CsPbBr_(3)films with full coverage,high purity,high crystallinity,micro-sized grains can be obtained at a low temperature of 150℃.Carbon-electrode PSCs with these desired CsPbBr_(3)films yield the record-high efficiency of 10.27%coupled with excellent operation stability.Meanwhile,the 1 cm^(2)area one with the superior efficiency of 8.00%as well as the flexible one with the champion efficiency of 8.27%and excellent mechanical bending characteristics are also achieved. 展开更多
关键词 carbon-electrode perovskite solar cells crystal orientation engineering CsPbBr_(3) low temperature two-step sequential deposition
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3D DEM simulation of hard rock fracture in deep tunnel excavation induced by changes in principal stress magnitude and orientation 被引量:2
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作者 Weiqi Wang Xia-Ting Feng +2 位作者 Qihu Wang Rui Kong Chengxiang Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3870-3884,共15页
To achieve the loading of the stress path of hard rock,the spherical discrete element model(DEM)and the new flexible membrane technology were utilized to realize the transient loading of three principal stresses with ... To achieve the loading of the stress path of hard rock,the spherical discrete element model(DEM)and the new flexible membrane technology were utilized to realize the transient loading of three principal stresses with arbitrary magnitudes and orientations.Furthermore,based on the deep tunnel of China Jinping Underground Laboratory II(CJPL-II),the deformation and fracture evolution characteristics of deep hard rock induced by excavation stress path were analyzed,and the mechanisms of transient loading-unloading and stress rotation-induced fractures were revealed from a mesoscopic perspective.The results indicated that the stressestrain curve exhibits different trends and degrees of sudden changes when subjected to transient changes in principal stress,accompanied by sudden changes in strain rate.Stress rotation induces spatially directional deformation,resulting in fractures of different degrees and orientations,and increasing the degree of deformation anisotropy.The correlation between the degree of induced fracture and the unloading magnitude of minimum principal stress,as well as its initial level is significant and positive.The process of mechanical response during transient unloading exhibits clear nonlinearity and directivity.After transient unloading,both the minimum principal stress and minimum principal strain rate decrease sharply and then tend to stabilize.This occurs from the edge to the interior and from the direction of the minimum principal stress to the direction of the maximum principal stress on theε1-ε3 plane.Transient unloading will induce a tensile stress wave.The ability to induce fractures due to changes in principal stress magnitude,orientation and rotation paths gradually increases.The analysis indicates a positive correlation between the abrupt change amplitude of strain rate and the maximum unloading magnitude,which is determined by the magnitude and rotation of principal stress.A high tensile strain rate is more likely to induce fractures under low minimum principal stress. 展开更多
关键词 Deep hard rock tunnel Three-dimensional(3D)discrete element model(DEM) Magnitude and orientation of principal stress Transient unloading Fracture mechanism
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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS
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作者 Jiaqi Hu Zheng Liu +1 位作者 Zuoliang Ning Hong Gao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期281-294,共14页
Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tes... Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS. 展开更多
关键词 Magnesium alloy orientation CORROSION Fatigue crack growth
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Evaluation of New Graduate Nursing Orientation Program
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作者 Elizabeth Arroyo 《Open Journal of Nursing》 2024年第8期433-446,共14页
The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nu... The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nurses to gain the confidence, competence, and critical thinking skills for providing safe patient care. The issue occurring within the organization is that there is an increasing rise in the number of turnover rates of new graduates leaving the hospital, thus making evaluating the program a necessity to problem-solving. There has been no evaluation of the program in the past five years to reveal why the increase in the recent turnover rates. The data collected during the interview process was coded and categorized into three main sections: organizational, substantive, and theoretical. The evaluator used an organizational category to investigate for board areas or issues within the problem attempting to be solved. The evaluator concluded from the results and findings that the issue, a poor preceptor-preceptee relationship was seen by all stakeholders involved. The literature presented concludes that continuous evaluation of orientation programs is crucial for the professional and personal growth of new graduate nurses in the hospital. 展开更多
关键词 New Graduate Nurses PRECEPTORS TURNOVER orientation
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Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials
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作者 Xinyou He Shilin Su +3 位作者 Bao Zhang Zhiming Xiao Zibo Zhang Xing Ou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期213-222,I0005,共11页
Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in t... Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in the properties of Ni-rich cathodes.The disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is unclarified.Herein,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation process.Combining finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are unraveled.Specifically,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution behavior.Meanwhile,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic processes.Closed-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic performance.This precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes. 展开更多
关键词 Ni-rich cathode Grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion
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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 Vitis vinifera L. orientated rows Berry composition SUGAR PHENOLIC Light quality Solar radiation
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Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries
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作者 Hui Li Gang Wang +3 位作者 Jin Hu Jun Li Jiaxu Huang Shaolin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期129-139,共11页
The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines ... The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current collectors.Specifically,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition.Unlike approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics.The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge rate.This study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal batteries.The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures. 展开更多
关键词 copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation
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Synergistic effect of orientation and temperature on slip behavior and precipitation behavior of Al−Cu−Li single crystals
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作者 Zhen JIANG Chen-qi LEI +4 位作者 Jia-jun DING Chun-nan ZHU Dong-feng SHI Jin ZHANG Guo-qing WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第11期3554-3568,共15页
The slip behavior and precipitation behavior of four Al−Cu−Li single crystals with varying orientations at different temperatures were investigated using electron backscattering diffraction(EBSD)and transmission elect... The slip behavior and precipitation behavior of four Al−Cu−Li single crystals with varying orientations at different temperatures were investigated using electron backscattering diffraction(EBSD)and transmission electron microscopy(TEM).The maximum differences in yield strength and ductility of the single crystals at room temperature are 41.6%and 14.7%,respectively.This indicates that the mechanical properties are strongly influenced by the crystal orientation.Moreover,grains with varying orientations exhibit distinct slip characteristics,including slip homogenization,slip localization,and multiple slip.In single crystal SC1,slip localization primarily contributes to its inferior ductility compared to other grains.Nevertheless,during deformation at 250℃,the distinct morphology and distribution of precipitates in the crystals are also correlated with orientation,which causes the increase in the maximum elongation difference to 20.8%in all selected single crystals.Notably,SC1,with a precipitate volume fraction of 2.65%,exhibits more severe slip localization compared to room temperature conditions,while SC2,with a precipitate volume fraction of 4.79%,demonstrates cross-slip characteristics,significantly enhancing the plastic deformation capacity of the Al−Cu−Li alloy. 展开更多
关键词 Al−Cu−Li alloy single crystal slip behavior oriented precipitation deformation mechanism
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An Expert System to Detect Political Arabic Articles Orientation Using CatBoost Classifier Boosted by Multi-Level Features
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作者 Saad M.Darwish Abdul Rahman M.Sabri +1 位作者 Dhafar Hamed Abd Adel A.Elzoghabi 《Computer Systems Science & Engineering》 2024年第6期1595-1624,共30页
The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orient... The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orientation detection.Political articles(especially in the Arab world)are different from other articles due to their subjectivity,in which the author’s beliefs and political affiliation might have a significant influence on a political article.With categories representing the main political ideologies,this problem may be thought of as a subset of the text categorization(classification).In general,the performance of machine learning models for text classification is sensitive to hyperparameter settings.Furthermore,the feature vector used to represent a document must capture,to some extent,the complex semantics of natural language.To this end,this paper presents an intelligent system to detect political Arabic article orientation that adapts the categorical boosting(CatBoost)method combined with a multi-level feature concept.Extracting features at multiple levels can enhance the model’s ability to discriminate between different classes or patterns.Each level may capture different aspects of the input data,contributing to a more comprehensive representation.CatBoost,a robust and efficient gradient-boosting algorithm,is utilized to effectively learn and predict the complex relationships between these features and the political orientation labels associated with the articles.A dataset of political Arabic texts collected from diverse sources,including postings and articles,is used to assess the suggested technique.Conservative,reform,and revolutionary are the three subcategories of these opinions.The results of this study demonstrate that compared to other frequently used machine learning models for text classification,the CatBoost method using multi-level features performs better with an accuracy of 98.14%. 展开更多
关键词 Political articles orientation detection CatBoost classifier multi-level features context-based classification social networks machine learning stylometric features
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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 Plateau Areas Patients with High-Risk Pregnancies problem-based Learning Health Education Health Knowledge Attitude and Practice Coping Skills
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Hybrid Teaching Reform of Veterinary Microbiology Based on the Combination of Virtual Simulation and Problem-Based Learning
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作者 Jiedan Liao 《Journal of Contemporary Educational Research》 2024年第9期1-9,共9页
The Veterinary Microbiology course is centered around the diagnosis and testing of pathogenic microorganisms,with the core value of“moral education and character development.”It reconstructs multidimensional teachin... The Veterinary Microbiology course is centered around the diagnosis and testing of pathogenic microorganisms,with the core value of“moral education and character development.”It reconstructs multidimensional teaching resources by integrating disciplinary achievements with clinical cases and implements a hybrid teaching approach combining virtual simulation and problem-based learning(PBL)through the“three stages+four models+three reflections”framework.Dual-qualification teachers employ various teaching methods,create a“six-in-one”model for ideological and political education,and conduct formative assessments based on the principles of diversified objectives and process emphasis.The hybrid teaching reform addresses issues such as fragmented knowledge,insufficient class hours,weak animal disease diagnostic abilities among students,limited application and expansion of knowledge points,and students’lack of proactive critical thinking skills.The application of hybrid teaching has shown significant advantages and effectiveness,providing a reference for teaching reform in similar microbiology courses. 展开更多
关键词 Veterinary Microbiology Hybrid teaching Virtual simulation problem-based learning Teaching reform
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Analysis of the Role of Problem-Based Independent Learning Model in Teaching Cerebral Ischemic Stroke First Aid in Emergency Medicine
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作者 Hua Liu 《Journal of Contemporary Educational Research》 2024年第6期16-21,共6页
Objective:To analyze the effect of using a problem-based(PBL)independent learning model in teaching cerebral ischemic stroke(CIS)first aid in emergency medicine.Methods:90 interns in the emergency department of our ho... Objective:To analyze the effect of using a problem-based(PBL)independent learning model in teaching cerebral ischemic stroke(CIS)first aid in emergency medicine.Methods:90 interns in the emergency department of our hospital from May 2022 to May 2023 were selected for the study.They were divided into Group A(45,conventional teaching method)and Group B(45 cases,PBL independent learning model)by randomized numerical table method to compare the effects of the two groups.Results:The teaching effect indicators and student satisfaction scores in Group B were higher than those in Group A(P<0.05).Conclusion:The use of the PBL independent learning model in the teaching of CIS first aid can significantly improve the teaching effect and student satisfaction. 展开更多
关键词 problem-based independent learning model Emergency medicine Ischemic stroke First aid teaching SATISFACTION
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Nonlinear Time History Analysis for the Different Column Orientations under Seismic Wave Synthetic Approach
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作者 Mo Shi Peng Wang +1 位作者 Xiaoyan Xu Yeol Choi 《World Journal of Engineering and Technology》 2024年第3期587-616,共30页
The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving ... The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving seismic design to mitigate earthquake-induced damages and enhance structural performance. In this study, a specific reinforced concrete (RC) frame structure at Kyungpook National University, designed for educational purposes, is analyzed as a representative case. Utilizing SAP 2000, the research conducts a nonlinear time history analysis to assess the structural performance under seismic conditions. The primary objective is to evaluate the influence of different column section designs, while maintaining identical column section areas, on structural behavior. The study employs two distinct seismic waves from Abeno (ABN) and Takatori (TKT) for the analysis, comparing the structural performance under varying seismic conditions. Key aspects examined include displacement, base shear force, base moment, joint radians, and layer displacement angle. This research is anticipated to serve as a valuable reference for seismic restraint reinforcement work on RC buildings, enriching the methods used for evaluating structures through nonlinear time history analysis based on the synthetic seismic wave approach. 展开更多
关键词 Nonlinear Time History Analysis Nonlinear Dynamic Analysis Seismic Wave Synthetic Seismic Restraint RC Frame Structure Column orientation
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The Application of“Problem-Based Learning+Flipped Classroom”Teaching Model in Bilingual Education
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作者 Xuan Zhang Songlin Wang 《Journal of Contemporary Educational Research》 2024年第11期215-221,共7页
This study focuses on the application of the“PBL(problem-based learning)+Flipped Classroom”teaching model in bilingual education,aiming to explore its potential to enhance the quality and effectiveness of bilingual ... This study focuses on the application of the“PBL(problem-based learning)+Flipped Classroom”teaching model in bilingual education,aiming to explore its potential to enhance the quality and effectiveness of bilingual teaching.PBL emphasizes learning through the resolution of real-world problems,while the Flipped Classroom advocates that students acquire basic knowledge through self-study before class,dedicating class time to in-depth discussions and practical activities.The integration of these two teaching models in bilingual education aims to stimulate students’interest in learning,improve their autonomous learning abilities,enhance critical thinking,and foster cross-cultural communication skills.Through literature review,case analysis,and empirical research,this study first examines the current applications and challenges of PBL and the Flipped Classroom in bilingual education.Subsequently,it elaborates on the specific implementation steps of the“PBL+Flipped Classroom”teaching model in bilingual education,including problem design,preview material provision,cooperative learning,classroom activities,and language support.A comparative experiment is then conducted to analyze the impact of this teaching model on students’learning motivation,academic performance,and cross-cultural communication skills.The results indicate that the“PBL+Flipped Classroom”teaching model significantly improves students’learning motivation and participation,enhances academic performance,and effectively boosts their cross-cultural communication skills.Furthermore,this model aids in cultivating students’autonomous learning abilities and critical thinking,providing an innovative and effective approach to bilingual education.This study offers new ideas and insights for the field of bilingual education,which is of great significance for promoting the innovation and development of bilingual teaching models. 展开更多
关键词 problem-based learning Flipped classroom Bilingual education Learning motivation Academic performance Cross-cultural communication skills
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Integrating Virtual Reality and Energy Analysis with BIM to Optimize Window-to-Wall Ratio and Building’s Orientation for Age-in-Place Design at the Conceptual Stage
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作者 Vafa Rostamiasl Ahmad Jrade 《Open Journal of Civil Engineering》 2024年第3期305-333,共29页
This study unfolds an innovative approach aiming to address the critical role of building design in global energy consumption, focusing on optimizing the Window-to-Wall Ratio (WWR), since buildings account for approxi... This study unfolds an innovative approach aiming to address the critical role of building design in global energy consumption, focusing on optimizing the Window-to-Wall Ratio (WWR), since buildings account for approximately 30% of total energy consumed worldwide. The greatest contributors to energy expenditure in buildings are internal artificial lighting and heating and cooling systems. The WWR, determined by the proportion of the building’s glazed area to its wall area, is a significant factor influencing energy efficiency and minimizing energy load. This study introduces the development of a semi-automated computer model designed to offer a real-time, interactive simulation environment, fostering improving communication and engagement between designers and owners. The said model serves to optimize both the WWR and building orientation to align with occupants’ needs and expectations, subsequently reducing annual energy consumption and enhancing the overall building energy performance. The integrated model incorporates Building Information Modeling (BIM), Virtual Reality (VR), and Energy Analysis tools deployed at the conceptual design stage, allowing for the amalgamation of owners’ inputs in the design process and facilitating the creation of more realistic and effective design strategies. 展开更多
关键词 Building Information Modeling (BIM) Virtual Reality (VR) Game Engine Energy Analysis Window-to-Wall Ratio Building orientation Computer Integration and Automation
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Precipitation orientation effect of 2124 aluminum alloy in creep aging 被引量:4
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作者 胥福顺 张劲 +1 位作者 邓运来 张新明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2067-2071,共5页
The precipitation behaviors of 2124 aluminum alloy under the conditions of artificial aging (AA), creep aging (CA) and creep aging with pre-deformation (PCA) were investigated by means of mechanical property and... The precipitation behaviors of 2124 aluminum alloy under the conditions of artificial aging (AA), creep aging (CA) and creep aging with pre-deformation (PCA) were investigated by means of mechanical property and microstructure. The results show that the mechanical properties of CA treated sample decrease significantly compared with AA treated sample. The yield strength of the CA treated sample falls by 14%, the tensile strength falls by 6.2%, and the elongation falls by 21%. Nevertheless, the mechanical properties of PCA sample are improved obviously, close to the AA treated sample. Moreover, the generation and control mechanisms of the precipitation orientation effect in 2124 aluminum alloy were studied. It is deduced that the key mechanism lies in the effect of dislocation. 展开更多
关键词 2124 aluminum alloy creep aging orientation effect DISLOCATION
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Influence of spiral crystal selector on crystal orientation of single crystal superalloy 被引量:3
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作者 张如林 陈丽娜 +3 位作者 李重河 王宁 鲁雄刚 任忠鸣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1092-1095,共4页
To increase efficiency and improve performance, reducing cost and emissions, advanced single crystal Ni-based superalloys are required in aerospace propulsion and power generating gas turbines. With the development of... To increase efficiency and improve performance, reducing cost and emissions, advanced single crystal Ni-based superalloys are required in aerospace propulsion and power generating gas turbines. With the development of alloy, significant improvements in casting techniques have been achieved by introducing the directionally solidified (DS) casting process followed by single crystal (SX) technique. The deviation of preferred orientation of single crystal superalloys is one of the most important defects in casting. In directional solidification equipment with high temperature gradient, single crystal specimens of DZ417G alloy were prepared successfully by the modified Bridgeman method with spiral grain selector. The orientation was investigated by means of X-ray diffraction (XRD) and electron backscattered diffraction (EBSD).The results show that the crystal selector with a smaller angle can effectively reduce the deviation of preferred orientation. 展开更多
关键词 nickel-base superalloy directional solidification single crystal superalloy crystal orientation spiral grain selector
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Effect of crystal orientation on tensile mechanical properties of single-crystal tungsten nanowire 被引量:4
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作者 马彬 饶秋华 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第9期2904-2910,共7页
Based on the high-purity single-crystal tungsten nanowire firstly prepared by the metal-catalyzed vapor-phase reaction method, molecular dynamics method was used to calculate tensile stress-strain curves and simulate ... Based on the high-purity single-crystal tungsten nanowire firstly prepared by the metal-catalyzed vapor-phase reaction method, molecular dynamics method was used to calculate tensile stress-strain curves and simulate microscopic deformation structures of the single-crystal tungsten nanowires with different crystal orientations of 〈100〉, 〈110〉and 〈111〉, in order to reveal the effect of crystal orientation on their tensile mechanical properties and failure mechanisms. Research results show that all of the stress-strain curves are classified into four stages: elastic stage, damage stage, yielding stage and failure stage, where 〈100〉orientation has a special hardening stage after yielding and two descending stages. The crystal orientation has little effect on elastic modulus but great effect on tensile strength, yielding strength and ductility, depending on different atomic surface energies and principal sliding planes. The calculated values of elastic modulus are in good agreement with the tested values of elastic modulus. 展开更多
关键词 crystal orientation stress-strain curve failure mechanism molecular dynamics single-crystal tungsten nanowire
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Perceptual Learning of Grate Orientation Discrimination in Cats 被引量:1
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作者 华田苗 万安 +2 位作者 王赦焱 梅斌 孙庆艳 《Zoological Research》 CAS CSCD 北大核心 2007年第1期95-100,共6页
Perceptual learning of orientation discrimination was investigated using cats. Two adult cats (Cat 1 and 2) were trained to monocularly discriminate between two static striped sinusoidal grates with 30° orienta... Perceptual learning of orientation discrimination was investigated using cats. Two adult cats (Cat 1 and 2) were trained to monocularly discriminate between two static striped sinusoidal grates with 30° orientation difference. After greater than 80% correct performance was reached, cats were then required to monocularly perform a discrimination between two grates with consecutively shifting orientation difference(2°, 4°, 6°, 8°, 10°, 12°, 16°, 20°, 24°, 30°) . The staircase method (two correct-down and one error-up) was applied throughout the training to track the threshold of orientation difference that cats could detect. The performance of detecting grates with varied orientation difference was measured respectively for beth trained and untrained eyes before and after training. Our results showed that the learning effect of discrimination for grates with a fixed orientation difference transferred completely from the trained eye to the untrained eye, whereas the inter-eye transfer for detecting °ates with gradually reducing orientation difference was almost nonegrates. The two opposite learning effects in the same subject strongly suggest that different information processing mechanisms might mediate the learning processes. 展开更多
关键词 Perceptual learning orientation discrimination CAT
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LOW COST IMPLEMENTATION OF SPEED SENSORLESS INDUCTION MOTOR CONTROL USING STATOR FLUX ORIENTATION 被引量:2
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作者 李勇 黄文新 胡育文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第1期34-40,共7页
The control platform of the induction motor (IM) with low costs is developed by using DSP MC56F8013 with a good performance/price rtaio. The control algorithm for the speed sensorless IM is studied based on the stat... The control platform of the induction motor (IM) with low costs is developed by using DSP MC56F8013 with a good performance/price rtaio. The control algorithm for the speed sensorless IM is studied based on the stator flux orientation (SFO). The algorithm structure is simple to be implemented and cannot be influenced by motor parameters, The improved stator flux estimation is used to compensate errors caused by the low pass filter (LPF). A new speed regulator is designed to ensure the system working with the maximal torque in the transient state. The system simulation and the prototype experiment are made. Results show that the con- trol system has good dynamic and static performance. 展开更多
关键词 induction motor stator flux orientation speed sensorless control algorithm
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