Investigating thermal transport mechanisms at the interface between phase change materials(PCMs)and high thermally conductive fillers has become increasingly significant in developing phase change energy storage techn...Investigating thermal transport mechanisms at the interface between phase change materials(PCMs)and high thermally conductive fillers has become increasingly significant in developing phase change energy storage technologies.This study explores the interfacial thermal transport between a representative PCM,erythritol,and various fillers,including crystalline(Si C,Si_(3)N_(4))and amorphous(Si O_(2))nanoparticles,using molecular dynamics(MD)simulations.Additionally,time-domain thermoreflectance(TDTR)experiments were performed to quantify the interfacial thermal conductance between erythritol and the three types of fillers,yielding values of 50.1,40.0,and25.6 MW m^(–2)K^(-1).These results align well with the trends observed in the simulations.Furthermore,the underlying mechanisms of interfacial heat transfer were analyzed by examining the phonon density of states,overlap energy,and interaction energy.This research provides innovative insights into nanoscale interfacial thermal transport in composite PCMs.This could lead to significant advancements in thermal management technologies,particularly in developing more efficient thermal energy storage systems.展开更多
Enabling as the second phase of the Production-Oriented Approach(POA)instruction(Wen,2015),plays a vital role in determining the quality of productive performance of English language learners.To explore how to apply t...Enabling as the second phase of the Production-Oriented Approach(POA)instruction(Wen,2015),plays a vital role in determining the quality of productive performance of English language learners.To explore how to apply theoretical principles of enabling to practice,this paper interprets theoretical principles and reports the practice of the classroom implementation of enabling.The paper proposes a definition for enabling,clarifies the confusion between enabling and scaffolding,and clears up some misunderstandings about enabling.It explains three criteria for effective enabling,namely,alignment,gradualness,and variety,and elaborates on the relations among them.Based on the teaching material of Unit 7 of iEnglish,the paper demonstrates how to design and implement enabling activities under the guidance of these three criteria and evaluates the actual effectiveness of the enabling implemented in the classroom.展开更多
目的:系统评价柴胡桂枝干姜汤加减治疗失眠的有效性。方法:通过检索中国期刊全文数据库(CNKI)、中文科技期刊数据库(VIP)、中国学术期刊数据库(CSPD)、PubMed和Web of Science,收集柴胡桂枝干姜汤加减治疗失眠的随机对照试验(RCT)。数...目的:系统评价柴胡桂枝干姜汤加减治疗失眠的有效性。方法:通过检索中国期刊全文数据库(CNKI)、中文科技期刊数据库(VIP)、中国学术期刊数据库(CSPD)、PubMed和Web of Science,收集柴胡桂枝干姜汤加减治疗失眠的随机对照试验(RCT)。数据分析采用RevMan 5.4软件,对纳入的研究进行Meta分析,评价其临床疗效总有效率、匹兹堡睡眠质量指数(PSQI)评分。结果:一共检索到148篇文献,共纳入10项研究,总计681例患者。Meta分析结果显示,柴胡桂枝干姜汤加减治疗失眠的临床总有效率显著高于对照组,差异有统计学意义(RR=1.36,95%CI为1.25~1.49,P<0.00001),且PSQI评分改善更显著,差异有统计学意义(MD=-2.28,95%CI为-3.70~-0.86,P=0.002)。结论:现有的研究证据表明,柴胡桂枝干姜汤加减治疗失眠可有效提高临床疗效,改善睡眠质量,且不良反应较少,具有良好的安全性。但目前尚未能证明其联合其他疗法在降低PSQI评分方面有明显优势。展开更多
Currently,most trains are equipped with dedicated cameras for capturing pantograph videos.Pantographs are core to the high-speed-railway pantograph-catenary system,and their failure directly affects the normal operati...Currently,most trains are equipped with dedicated cameras for capturing pantograph videos.Pantographs are core to the high-speed-railway pantograph-catenary system,and their failure directly affects the normal operation of high-speed trains.However,given the complex and variable real-world operational conditions of high-speed railways,there is no real-time and robust pantograph fault-detection method capable of handling large volumes of surveillance video.Hence,it is of paramount importance to maintain real-time monitoring and analysis of pantographs.Our study presents a real-time intelligent detection technology for identifying faults in high-speed railway pantographs,utilizing a fusion of self-attention and convolution features.We delved into lightweight multi-scale feature-extraction and fault-detection models based on deep learning to detect pantograph anomalies.Compared with traditional methods,this approach achieves high recall and accuracy in pantograph recognition,accurately pinpointing issues like discharge sparks,pantograph horns,and carbon pantograph-slide malfunctions.After experimentation and validation with actual surveillance videos of electric multiple-unit train,our algorithmic model demonstrates real-time,high-accuracy performance even under complex operational conditions.展开更多
BACKGROUND Due to their significantly lower incidence than colorectal polyps and macroscopic features resembling those of hyperplastic polyps,rectal neuroendocrine tumors(rNETs)are frequently misdiagnosed and resected...BACKGROUND Due to their significantly lower incidence than colorectal polyps and macroscopic features resembling those of hyperplastic polyps,rectal neuroendocrine tumors(rNETs)are frequently misdiagnosed and resected as polyps.To date,no reports have been written on the application of artificial intelligence for assisting in the white-light endoscopy of rNETs.AIM To establish a neuroendocrine tumor lesion detection algorithm based on the YOLOv7 model and evaluate the performance of the algorithm in identifying neuroendocrine tumors.METHODS In total,137748 white-light endoscopic images were collected in this study,including 2232 images of rNET,4429 images of submucosal lesions other than rNET,42563 images of polyps,and 88593 images of normal mucosa.All the images were randomly divided into a training set,a validation set,and a test set.To evaluate the ability of the algorithm to diagnose rNETs,we selected 1578 images to form the test set.The performance of the algorithm was compared with that of endoscopists at different levels.RESULTS The accuracy of the algorithm in identifying rNET from all the images was 97.8%,the sensitivity was 72.6%,the specificity was 99.7%,the positive predictive value was 93.9%,and the negative predictive value was 98.1%.CONCLUSION Our model,which was based on YOLOv7,could effectively detect rNET lesions,which was better than that of most endoscopists.展开更多
BACKGROUND Computer-aided diagnosis(CAD)may assist endoscopists in identifying and classifying polyps during colonoscopy for detecting colorectal cancer.AIM To build a system using CAD to detect and classify polyps ba...BACKGROUND Computer-aided diagnosis(CAD)may assist endoscopists in identifying and classifying polyps during colonoscopy for detecting colorectal cancer.AIM To build a system using CAD to detect and classify polyps based on the Yamada classification.METHODS A total of 24045 polyp and 72367 nonpolyp images were obtained.We established a computer-aided detection and Yamada classification model based on the YOLOv7 neural network algorithm.Frame-based and image-based evaluation metrics were employed to assess the performance.RESULTS Computer-aided detection and Yamada classification screened polyps with a precision of 96.7%,a recall of 95.8%,and an F1-score of 96.2%,outperforming those of all groups of endoscopists.In regard to the Yamada classification of polyps,the CAD system displayed a precision of 82.3%,a recall of 78.5%,and an F1-score of 80.2%,outper-forming all levels of endoscopists.In addition,according to the image-based method,the CAD had an accuracy of 99.2%,a specificity of 99.5%,a sensitivity of 98.5%,a positive predictive value of 99.0%,a negative predictive value of 99.2%for polyp detection and an accuracy of 97.2%,a specificity of 98.4%,a sensitivity of 79.2%,a positive predictive value of 83.0%,and a negative predictive value of 98.4%for poly Yamada classification.CONCLUSION We developed a novel CAD system based on a deep neural network for polyp detection,and the Yamada classi-fication outperformed that of nonexpert endoscopists.This CAD system could help community-based hospitals enhance their effectiveness in polyp detection and classification.展开更多
Copper–carbon(Cu–C)composites have achieved great success in various fields owing to the greatly improved electrical properties compared to pure Cu,for example,a two-order-of-magnitude increase in current-carrying c...Copper–carbon(Cu–C)composites have achieved great success in various fields owing to the greatly improved electrical properties compared to pure Cu,for example,a two-order-of-magnitude increase in current-carrying capacity(ampacity).However,the frequent fuse failure caused by the poor thermal transport at the Cu–C heterointerface is still the main factor affecting the ampacity.In this study,we unconventionally leverage atomic distortion at Cu grain boundaries to alter the local atomic environments,thereby placing a premium on noticeable enhancement of phonon coupling at the Cu–C heterointerface.Without introducing any additional materials,interfacial thermal transport can be regulated solely through rational microstructural design.This new strategy effectively improves the interfacial thermal conductance by three-fold,reaching the state-of-the-art level in van der Waals(vdW)interface regulation.It can be an innovative strategy for interfacial thermal management by turning the detrimental grain boundaries into a beneficial thermal transport accelerator.展开更多
Based on conventional particle swarm optimization(PSO),this paper presents an efficient and reliable heuristic approach using PSO with an adaptive random inertia weight(ARIW)strategy,referred to as the ARIW-PSO algori...Based on conventional particle swarm optimization(PSO),this paper presents an efficient and reliable heuristic approach using PSO with an adaptive random inertia weight(ARIW)strategy,referred to as the ARIW-PSO algorithm,to build a multi-objective optimization model for reservoir operation.Using the triangular probability density function,the inertia weight is randomly generated,and the probability density function is automatically adjusted to make the inertia weight generally greater in the initial stage of evolution,which is suitable for global searches.In the evolution process,the inertia weight gradually decreases,which is beneficial to local searches.The performance of the ARIWPSO algorithm was investigated with some classical test functions,and the results were compared with those of the genetic algorithm(GA),the conventional PSO,and other improved PSO methods.Then,the ARIW-PSO algorithm was applied to multi-objective optimal dispatch of the Panjiakou Reservoir and multi-objective flood control operation of a reservoir group on the Luanhe River in China,including the Panjiakou Reservoir,Daheiting Reservoir,and Taolinkou Reservoir.The validity of the multi-objective optimization model for multi-reservoir systems based on the ARIW-PSO algorithm was verified.展开更多
目的探究闽产食用菌的氨基酸组成特征及其营养价值。方法采用氨基酸自动分析仪分析食用菌氨基酸含量,利用鸡蛋蛋白模式和联合国粮食及农业组织(Food and Agriculture Organization,FAO)/世界卫生组织(World Health Organization,WHO)推...目的探究闽产食用菌的氨基酸组成特征及其营养价值。方法采用氨基酸自动分析仪分析食用菌氨基酸含量,利用鸡蛋蛋白模式和联合国粮食及农业组织(Food and Agriculture Organization,FAO)/世界卫生组织(World Health Organization,WHO)推荐的理想蛋白模式系统评价各食用菌的氨基酸营养价值。结果食用菌至少包含18种氨基酸,包括8种成人必需氨基酸、2种儿童必需氨基酸。成人必需氨基酸、非必需氨基酸、酸味类氨基酸、甜味类氨基酸、苦味类氨基酸、儿童必需氨基酸、药用氨基酸、支链氨基酸、增香与着色氨基酸、伯胺基氨基酸含量等特殊功效氨基酸含量分别为3.19%-10.90%、4.51%-16.24%、1.73%-7.77%、2.09%-7.39%、3.03%-9.73%、0.55%-2.30%、4.84%-17.16%、1.30%-4.86%、2.90%-12.06%、3.94%-14.89%,品种间含量差异明显。必需氨基酸与氨基酸总量的百分比、必需氨基酸与非必需氨基酸含量的百分比、氨基酸比值系数分、必需氨基酸指数和营养指数依次为40.86%-48.72%、69.10%-95.00%、46.19-88.18、58.37-83.43、7.12-24.53,品种间营养价值差异明显。蛋氨酸+胱氨酸均相对过剩,缬草氨酸、异亮氨酸、亮氨酸、赖氨酸表现严重不足,而苯丙氨酸+酪氨酸、苏氨酸、色氨酸各品种表现不一。通过聚类分析,样品可分为3大类:高、中、低品质蛋白组。结论 18种食用菌氨基酸组成及营养价值存在一定的差异,具有不同的开发应用前景。展开更多
基金supported by the National Natural Science Foundation of China(Nos.52222602,and52236006)the Fundamental Research Funds for the Central Universities(Nos.FRF-EYIT-23-05,and FRF-TP-22-001C1)+1 种基金Noncommunicable Chronic Diseases-National Science and Technology Major Project(No.2023ZD0500902)the member of the Youth Innovation Promotion Association Foundation of CAS,China(No.2023310)。
文摘Investigating thermal transport mechanisms at the interface between phase change materials(PCMs)and high thermally conductive fillers has become increasingly significant in developing phase change energy storage technologies.This study explores the interfacial thermal transport between a representative PCM,erythritol,and various fillers,including crystalline(Si C,Si_(3)N_(4))and amorphous(Si O_(2))nanoparticles,using molecular dynamics(MD)simulations.Additionally,time-domain thermoreflectance(TDTR)experiments were performed to quantify the interfacial thermal conductance between erythritol and the three types of fillers,yielding values of 50.1,40.0,and25.6 MW m^(–2)K^(-1).These results align well with the trends observed in the simulations.Furthermore,the underlying mechanisms of interfacial heat transfer were analyzed by examining the phonon density of states,overlap energy,and interaction energy.This research provides innovative insights into nanoscale interfacial thermal transport in composite PCMs.This could lead to significant advancements in thermal management technologies,particularly in developing more efficient thermal energy storage systems.
文摘Enabling as the second phase of the Production-Oriented Approach(POA)instruction(Wen,2015),plays a vital role in determining the quality of productive performance of English language learners.To explore how to apply theoretical principles of enabling to practice,this paper interprets theoretical principles and reports the practice of the classroom implementation of enabling.The paper proposes a definition for enabling,clarifies the confusion between enabling and scaffolding,and clears up some misunderstandings about enabling.It explains three criteria for effective enabling,namely,alignment,gradualness,and variety,and elaborates on the relations among them.Based on the teaching material of Unit 7 of iEnglish,the paper demonstrates how to design and implement enabling activities under the guidance of these three criteria and evaluates the actual effectiveness of the enabling implemented in the classroom.
文摘目的:系统评价柴胡桂枝干姜汤加减治疗失眠的有效性。方法:通过检索中国期刊全文数据库(CNKI)、中文科技期刊数据库(VIP)、中国学术期刊数据库(CSPD)、PubMed和Web of Science,收集柴胡桂枝干姜汤加减治疗失眠的随机对照试验(RCT)。数据分析采用RevMan 5.4软件,对纳入的研究进行Meta分析,评价其临床疗效总有效率、匹兹堡睡眠质量指数(PSQI)评分。结果:一共检索到148篇文献,共纳入10项研究,总计681例患者。Meta分析结果显示,柴胡桂枝干姜汤加减治疗失眠的临床总有效率显著高于对照组,差异有统计学意义(RR=1.36,95%CI为1.25~1.49,P<0.00001),且PSQI评分改善更显著,差异有统计学意义(MD=-2.28,95%CI为-3.70~-0.86,P=0.002)。结论:现有的研究证据表明,柴胡桂枝干姜汤加减治疗失眠可有效提高临床疗效,改善睡眠质量,且不良反应较少,具有良好的安全性。但目前尚未能证明其联合其他疗法在降低PSQI评分方面有明显优势。
基金supported by the National Key R&D Program of China(No.2022YFB4301102).
文摘Currently,most trains are equipped with dedicated cameras for capturing pantograph videos.Pantographs are core to the high-speed-railway pantograph-catenary system,and their failure directly affects the normal operation of high-speed trains.However,given the complex and variable real-world operational conditions of high-speed railways,there is no real-time and robust pantograph fault-detection method capable of handling large volumes of surveillance video.Hence,it is of paramount importance to maintain real-time monitoring and analysis of pantographs.Our study presents a real-time intelligent detection technology for identifying faults in high-speed railway pantographs,utilizing a fusion of self-attention and convolution features.We delved into lightweight multi-scale feature-extraction and fault-detection models based on deep learning to detect pantograph anomalies.Compared with traditional methods,this approach achieves high recall and accuracy in pantograph recognition,accurately pinpointing issues like discharge sparks,pantograph horns,and carbon pantograph-slide malfunctions.After experimentation and validation with actual surveillance videos of electric multiple-unit train,our algorithmic model demonstrates real-time,high-accuracy performance even under complex operational conditions.
基金Supported by the Municipal Key Science and Technology Program of Leshan,No.23SZD039National Natural Science Foundation of China,No.82470539.
文摘BACKGROUND Due to their significantly lower incidence than colorectal polyps and macroscopic features resembling those of hyperplastic polyps,rectal neuroendocrine tumors(rNETs)are frequently misdiagnosed and resected as polyps.To date,no reports have been written on the application of artificial intelligence for assisting in the white-light endoscopy of rNETs.AIM To establish a neuroendocrine tumor lesion detection algorithm based on the YOLOv7 model and evaluate the performance of the algorithm in identifying neuroendocrine tumors.METHODS In total,137748 white-light endoscopic images were collected in this study,including 2232 images of rNET,4429 images of submucosal lesions other than rNET,42563 images of polyps,and 88593 images of normal mucosa.All the images were randomly divided into a training set,a validation set,and a test set.To evaluate the ability of the algorithm to diagnose rNETs,we selected 1578 images to form the test set.The performance of the algorithm was compared with that of endoscopists at different levels.RESULTS The accuracy of the algorithm in identifying rNET from all the images was 97.8%,the sensitivity was 72.6%,the specificity was 99.7%,the positive predictive value was 93.9%,and the negative predictive value was 98.1%.CONCLUSION Our model,which was based on YOLOv7,could effectively detect rNET lesions,which was better than that of most endoscopists.
基金Supported by Science and Technology Projects in Guangzhou,No.2023A04J2282。
文摘BACKGROUND Computer-aided diagnosis(CAD)may assist endoscopists in identifying and classifying polyps during colonoscopy for detecting colorectal cancer.AIM To build a system using CAD to detect and classify polyps based on the Yamada classification.METHODS A total of 24045 polyp and 72367 nonpolyp images were obtained.We established a computer-aided detection and Yamada classification model based on the YOLOv7 neural network algorithm.Frame-based and image-based evaluation metrics were employed to assess the performance.RESULTS Computer-aided detection and Yamada classification screened polyps with a precision of 96.7%,a recall of 95.8%,and an F1-score of 96.2%,outperforming those of all groups of endoscopists.In regard to the Yamada classification of polyps,the CAD system displayed a precision of 82.3%,a recall of 78.5%,and an F1-score of 80.2%,outper-forming all levels of endoscopists.In addition,according to the image-based method,the CAD had an accuracy of 99.2%,a specificity of 99.5%,a sensitivity of 98.5%,a positive predictive value of 99.0%,a negative predictive value of 99.2%for polyp detection and an accuracy of 97.2%,a specificity of 98.4%,a sensitivity of 79.2%,a positive predictive value of 83.0%,and a negative predictive value of 98.4%for poly Yamada classification.CONCLUSION We developed a novel CAD system based on a deep neural network for polyp detection,and the Yamada classi-fication outperformed that of nonexpert endoscopists.This CAD system could help community-based hospitals enhance their effectiveness in polyp detection and classification.
基金financial support from the National Natural Science Foundation of China(Nos.52222602 and 52476052)Fundamental Research Funds for the Central Universities(FRF-TP-22-001C1 and FRF-EYIT-23-05).
文摘Copper–carbon(Cu–C)composites have achieved great success in various fields owing to the greatly improved electrical properties compared to pure Cu,for example,a two-order-of-magnitude increase in current-carrying capacity(ampacity).However,the frequent fuse failure caused by the poor thermal transport at the Cu–C heterointerface is still the main factor affecting the ampacity.In this study,we unconventionally leverage atomic distortion at Cu grain boundaries to alter the local atomic environments,thereby placing a premium on noticeable enhancement of phonon coupling at the Cu–C heterointerface.Without introducing any additional materials,interfacial thermal transport can be regulated solely through rational microstructural design.This new strategy effectively improves the interfacial thermal conductance by three-fold,reaching the state-of-the-art level in van der Waals(vdW)interface regulation.It can be an innovative strategy for interfacial thermal management by turning the detrimental grain boundaries into a beneficial thermal transport accelerator.
基金supported by the Foundation of the Scientific and Technological Innovation Team of Colleges and Universities in Henan Province(Grant No.181RTSTHN009)the Foundation of the Key Laboratory of Water Environment Simulation and Treatment in Henan Province(Grant No.2017016).
文摘Based on conventional particle swarm optimization(PSO),this paper presents an efficient and reliable heuristic approach using PSO with an adaptive random inertia weight(ARIW)strategy,referred to as the ARIW-PSO algorithm,to build a multi-objective optimization model for reservoir operation.Using the triangular probability density function,the inertia weight is randomly generated,and the probability density function is automatically adjusted to make the inertia weight generally greater in the initial stage of evolution,which is suitable for global searches.In the evolution process,the inertia weight gradually decreases,which is beneficial to local searches.The performance of the ARIWPSO algorithm was investigated with some classical test functions,and the results were compared with those of the genetic algorithm(GA),the conventional PSO,and other improved PSO methods.Then,the ARIW-PSO algorithm was applied to multi-objective optimal dispatch of the Panjiakou Reservoir and multi-objective flood control operation of a reservoir group on the Luanhe River in China,including the Panjiakou Reservoir,Daheiting Reservoir,and Taolinkou Reservoir.The validity of the multi-objective optimization model for multi-reservoir systems based on the ARIW-PSO algorithm was verified.
文摘目的探究闽产食用菌的氨基酸组成特征及其营养价值。方法采用氨基酸自动分析仪分析食用菌氨基酸含量,利用鸡蛋蛋白模式和联合国粮食及农业组织(Food and Agriculture Organization,FAO)/世界卫生组织(World Health Organization,WHO)推荐的理想蛋白模式系统评价各食用菌的氨基酸营养价值。结果食用菌至少包含18种氨基酸,包括8种成人必需氨基酸、2种儿童必需氨基酸。成人必需氨基酸、非必需氨基酸、酸味类氨基酸、甜味类氨基酸、苦味类氨基酸、儿童必需氨基酸、药用氨基酸、支链氨基酸、增香与着色氨基酸、伯胺基氨基酸含量等特殊功效氨基酸含量分别为3.19%-10.90%、4.51%-16.24%、1.73%-7.77%、2.09%-7.39%、3.03%-9.73%、0.55%-2.30%、4.84%-17.16%、1.30%-4.86%、2.90%-12.06%、3.94%-14.89%,品种间含量差异明显。必需氨基酸与氨基酸总量的百分比、必需氨基酸与非必需氨基酸含量的百分比、氨基酸比值系数分、必需氨基酸指数和营养指数依次为40.86%-48.72%、69.10%-95.00%、46.19-88.18、58.37-83.43、7.12-24.53,品种间营养价值差异明显。蛋氨酸+胱氨酸均相对过剩,缬草氨酸、异亮氨酸、亮氨酸、赖氨酸表现严重不足,而苯丙氨酸+酪氨酸、苏氨酸、色氨酸各品种表现不一。通过聚类分析,样品可分为3大类:高、中、低品质蛋白组。结论 18种食用菌氨基酸组成及营养价值存在一定的差异,具有不同的开发应用前景。
