为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决...为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决定分解模态数和带宽,结合最小二乘-旋转不变技术(total least square-estimating signal parameter via rotational invariance techniques,TLS-ESPRIT)对分解出的振荡分量进行参数辨识,无需另外使用降噪算法。通过复合信号测试法、PSCAD/EMTDC电磁暂态仿真法验证了所提方法的有效性。最后,将所提方法与改进Prony算法、MCEEMD法在不同噪声水平和振荡频率下进行对比,结果表明,所提方法能够有效地抑制原始信号的噪声干扰,对耦合的次/超同步振荡信号分解更加准确,参数辨识结果可靠性较高,对风电系统振荡溯源、改善系统阻尼具有一定的参考意义。展开更多
Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.T...Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.展开更多
Precise transverse emittance assessment in electron beams is crucial for advancing high-brightness beam injectors.As opposed to intricate methodologies that use specialized devices,quadrupole focusing strength scannin...Precise transverse emittance assessment in electron beams is crucial for advancing high-brightness beam injectors.As opposed to intricate methodologies that use specialized devices,quadrupole focusing strength scanning(Q-scanning)techniques offer notable advantages for various injectors owing to their inherent convenience and cost-effectiveness.However,their stringent approximation conditions lead to inevitable errors in practical operation,thereby limiting their widespread application.This study addressed these challenges by revisiting the analytical derivation procedure and investigating the effects of the underlying approximation conditions.Preliminary corrections were explored through a combination of data processing analysis and numerical simulations.Furthermore,based on theoretical derivations,virtual measurements using beam dynamics calculations were employed to evaluate the correction reliability.Subsequent experimental validations were performed at the Huazhong University of Science and Technology injector to verify the effectiveness of the proposed compensation method.Both the virtual and experimental results confirm the feasibility and reliability of the enhanced Q-scanning-based diagnosis for transverse emittance in typical beam injectors operating under common conditions.Through the integration of these corrections and compensations,enhanced Q-scanning-based techniques emerge as promising alternatives to traditional emittance diagnosis methods.展开更多
This paper presents a high-fidelity lumpedparameter(LP)thermal model(HF-LPTM)for permanent magnet synchronous machines(PMSMs)in electric vehicle(EV)applications,where various cooling techniques are considered,includin...This paper presents a high-fidelity lumpedparameter(LP)thermal model(HF-LPTM)for permanent magnet synchronous machines(PMSMs)in electric vehicle(EV)applications,where various cooling techniques are considered,including frame forced air/liquid cooling,oil jet cooling for endwinding,and rotor shaft cooling.To address the temperature misestimation in the LP thermal modelling due to assumptions of concentrated loss input and uniform heat flows,the developed HF-LPTM introduces two compensation thermal resistances for the winding and PM components,which are analytically derived from the multi-dimensional heat transfer equations and are robust against different load/thermal conditions.As validated by the finite element analysis method and experiments,the conventional LPTMs exhibit significant winding temperature deviations,while the proposed HF-LPTM can accurately predict both the midpoint and average temperatures.The developed HFLPTM is further used to assess the effectiveness of various cooling techniques under different scenarios,i.e.,steady-state thermal states under the rated load condition,and transient temperature profiles under city,freeway,and hybrid(city+freeway)driving cycles.Results indicate that no single cooling technique can maintain both winding and PM temperatures within safety limits.The combination of frame liquid cooling and oil jet cooling for end winding can sufficiently mitigate PMSM thermal stress in EV applications.展开更多
With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly progressed...With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly progressed.This paper examines the advancements inDeepfake detection and defense technologies,emphasizing the shift from passive detection methods to proactive digital watermarking techniques.Passive detection methods,which involve extracting features from images or videos to identify forgeries,encounter challenges such as poor performance against unknown manipulation techniques and susceptibility to counter-forensic tactics.In contrast,proactive digital watermarking techniques embed specificmarkers into images or videos,facilitating real-time detection and traceability,thereby providing a preemptive defense againstDeepfake content.We offer a comprehensive analysis of digitalwatermarking-based forensic techniques,discussing their advantages over passivemethods and highlighting four key benefits:real-time detection,embedded defense,resistance to tampering,and provision of legal evidence.Additionally,the paper identifies gaps in the literature concerning proactive forensic techniques and suggests future research directions,including cross-domain watermarking and adaptive watermarking strategies.By systematically classifying and comparing existing techniques,this review aims to contribute valuable insights for the development of more effective proactive defense strategies in Deepfake forensics.展开更多
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object...One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.展开更多
Despite advancements in neuroimaging,false positive diagnoses of intracranial aneurysms remain a significant concern.This article examines the causes,prevalence,and implications of such false-positive diagnoses.We dis...Despite advancements in neuroimaging,false positive diagnoses of intracranial aneurysms remain a significant concern.This article examines the causes,prevalence,and implications of such false-positive diagnoses.We discuss how conditions like arterial occlusion with vascular stump formation and infundibular widening can mimic aneurysms,particularly in the anterior circulation.The article compares various imaging modalities,including computer tomography angiogram,magnetic resonance imaging/angiography,and digital subtraction angiogram,highlighting their strengths and limitations.We emphasize the im-portance of accurate differentiation to avoid unnecessary surgical interventions.The potential of emerging technologies,such as high-resolution vessel wall ima-ging and deep neural networks for automated detection,is explored as promising avenues for improving diagnostic accuracy.This manuscript underscores the need for continued research and clinical vigilance in the diagnosis of intracranial aneurysms.展开更多
Short process forming techniques for brazing and soldering materials can shorten the process,improve product quality,and increase production efficiency,which has received much attention from welding researchers.This r...Short process forming techniques for brazing and soldering materials can shorten the process,improve product quality,and increase production efficiency,which has received much attention from welding researchers.This review mainly summarized the research reports on short process forming techniques for brazing and soldering materials.Firstly,the traditional process and its shortcomings were presented.Secondly,the latest research of short process forming technologies,such as continuous casting technique,atomization powder technique,solder ball forming technique,and rapid solidification technique,was summarized,and the traditional forming performance of several brazing and soldering materials was introduced.Finally,the current restrictions and research trends of short process forming technique for brazing and solder materials were put forward,providing theoretical guidance and reference for related research and technique development in brazing and soldering field.展开更多
Low-voltage direct current(DC)microgrids have recently emerged as a promising and viable alternative to traditional alternating cur-rent(AC)microgrids,offering numerous advantages.Consequently,researchers are explorin...Low-voltage direct current(DC)microgrids have recently emerged as a promising and viable alternative to traditional alternating cur-rent(AC)microgrids,offering numerous advantages.Consequently,researchers are exploring the potential of DC microgrids across var-ious configurations.However,despite the sustainability and accuracy offered by DC microgrids,they pose various challenges when integrated into modern power distribution systems.Among these challenges,fault diagnosis holds significant importance.Rapid fault detection in DC microgrids is essential to maintain stability and ensure an uninterrupted power supply to critical loads.A primary chal-lenge is the lack of standards and guidelines for the protection and safety of DC microgrids,including fault detection,location,and clear-ing procedures for both grid-connected and islanded modes.In response,this study presents a brief overview of various approaches for protecting DC microgrids.展开更多
BACKGROUND Uniportal full-endoscopy(UFE)technique has been continuously developed and applied for treating lumbar spinal stenosis.However,achieving effective decompression outcome of using the UFE technique remains te...BACKGROUND Uniportal full-endoscopy(UFE)technique has been continuously developed and applied for treating lumbar spinal stenosis.However,achieving effective decompression outcome of using the UFE technique remains technically demanding and uncertain.Previously,we have proposed the biportal full-endoscopy(BFE)technique to integrate the respective advantages of both UFE and unilateral biportal endoscopy technique.There is limited published data on the comparison of clinical outcomes between biportal and UFE techniques in lumbar spinal stenosis with bilateral symptoms.AIM To contrast the clinical outcomes between biportal and UFE techniques for treating lumbar spinal stenosis with bilateral symptoms.METHODS This study retrospectively examined 100 patients diagnosed with lumbar spinal stenosis and bilateral symptoms.Among them,52 cases were part of group A(BFE technique group),and 48 cases belonged to group B(UFE technique group).The visual analogue scale(VAS),Oswestry Disability Index(ODI),and modified Macnab criteria were used to evaluate the clinical outcomes.RESULTS Group A had significantly shorter operation time than group B.Both groups experienced substantial relief in lower back and lower extremity pain on the severe side at postoperative 3 days,3 months,and 12 months.Group A had notably lower VAS scores for mild side lower extremity pain at postoperative 3 months and 12 months compared to group B.Group A's ODI scores were significantly lower at postoperative 3 months and 12 months,whereas group B's scores did not significantly differ from preoperative values.Group A's ODI scores were significantly lower than group B's at postoperative 3 months and 12 months.Group A had a significantly higher excellent and good response rate(94.23%)compared to group B(81.25%)at postoperative 12 months based on the modified Macnab scale outcomes.CONCLUSION The BFE technique offers multiple benefits,including reduced trauma and quicker recovery as a minimally invasive surgery,and enhanced decompression efficiency over the UFE technique when treating lumbar spinal stenosis with bilateral symptoms.展开更多
Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in ...Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in different database repositories every day. Most of the review data are useful to new customers for theier further purchases as well as existing companies to view customers feedback about various products. Data Mining and Machine Leaning techniques are familiar to analyse such kind of data to visualise and know the potential use of the purchased items through online. The customers are making quality of products through their sentiments about the purchased items from different online companies. In this research work, it is analysed sentiments of Headphone review data, which is collected from online repositories. For the analysis of Headphone review data, some of the Machine Learning techniques like Support Vector Machines, Naive Bayes, Decision Trees and Random Forest Algorithms and a Hybrid method are applied to find the quality via the customers’ sentiments. The accuracy and performance of the taken algorithms are also analysed based on the three types of sentiments such as positive, negative and neutral.展开更多
Objectives:The objective of this study was to assess the impact of two relaxation techniques,the Jacobson’s progressive muscle relaxation technique(JPMR),and the Benson’s relaxation technique(BRT),on the levels of s...Objectives:The objective of this study was to assess the impact of two relaxation techniques,the Jacobson’s progressive muscle relaxation technique(JPMR),and the Benson’s relaxation technique(BRT),on the levels of stress and anxiety experienced by patients undergoing coronary angioplasty.Materials and Methods:Quantitative research approach with quasi-experimental pre-test and posttest control group design was conducted with seventy coronary angioplasty patients from the Institute of Medical Science,and SUM Hospital,Bhubaneswar,Odisha.The participants were purposively selected and divided into Experimental Group 1(n=35)and Experimental Group 2(n=35).Each group received either BRT or JPMR for three consecutive days.Pretest and posttest data were collected using a structured demographic questionnaire and the modified depression anxiety stress scale-21.Results:Both BRT and JPMR significantly decreased the levels of stress and anxiety among patients undergoing angioplasty compared to baseline(P<0.05).However,there was no significant difference between the two techniques based on Fisher’s exact P value.This suggests that both interventions are effective in reducing stress and anxiety among angioplasty patients.Conclusion:BRT or JPMR are noninvasive,nonpharmacological interventions that effectively reduce stress and anxiety in patients undergoing angioplasty.These findings underscore the importance of incorporating relaxation techniques into nursing practice and hospital programs to enhance patient care and promote holistic well-being post-angioplasty.展开更多
Wheat is one of the primary grain crops in China and is widely cultivated.Successful cultivation requires careful selection of varieties,seeding,fertilization,and pest control to ensure adequate nutrient absorption by...Wheat is one of the primary grain crops in China and is widely cultivated.Successful cultivation requires careful selection of varieties,seeding,fertilization,and pest control to ensure adequate nutrient absorption by roots and improve lodging resistance and disease tolerance.This study investigated the cultivation techniques of the wheat variety New Century 999,and examined its growth stage characteristics and cultivation requirements.The analysis identifies challenges in its cultivation and provides recommendations for pre-sowing preparation,land preparation,seeding,fertilization,and management practices in both winter and spring.展开更多
Although legal liability is a key component of local regulations and ensures their effective implementation,existing research has paid insufficient attention to the techniques for setting legal liability clauses in th...Although legal liability is a key component of local regulations and ensures their effective implementation,existing research has paid insufficient attention to the techniques for setting legal liability clauses in the local legislation,due to a lack of systematic analysis.To address this gap,this paper employs the interview method to empirically examine the formation process,as well as the techniques for establishing legal liability in local legislation,with the aim of revealing the primary legislative techniques for formulating legal liability clauses in local legislation and their application principles.Drawing from these empirical findings and analytical insights,the research demonstrates that the legal liability-setting techniques in local legislation tend to exhibit a weak coherence with regard to logic and a strong policy orientation.These issues potentially create tension with the legal norms’demands for certainty,abstraction,and completeness.Therefore,this paper proposes a three-pronged framework to harmonize competing demands by respecting local particularities and achieving context-sensitive regulatory balance.This framework advocates that local legislative practice should(a)prioritize practical rationality and rule effectiveness over logical completeness,acknowledging inherent conflicts with traditional legislative models;(b)adopt a typological legislative method to balance normative principles with governance efficiency by transcending logic-experience binaries;and(c)establish a dynamic updating mechanism with regular evaluation to maintain adaptability to socio-economic evolution.展开更多
Figure 3 in the paper[Chin.Phys.B 34020701(2025)]contains an axis labeling error.The revised figure is provided.This modification does not affect the result presented in the paper.
文摘为解决现有辨识方法在针对耦合的次/超同步振荡参数提取过程中的噪声适应性差和模态混叠问题,该文提出了一种自适应的变分模态分解法(variational mode decomposition,VMD),定义残差损失总熵、中心频率的切比雪夫距离以及边缘熵共同决定分解模态数和带宽,结合最小二乘-旋转不变技术(total least square-estimating signal parameter via rotational invariance techniques,TLS-ESPRIT)对分解出的振荡分量进行参数辨识,无需另外使用降噪算法。通过复合信号测试法、PSCAD/EMTDC电磁暂态仿真法验证了所提方法的有效性。最后,将所提方法与改进Prony算法、MCEEMD法在不同噪声水平和振荡频率下进行对比,结果表明,所提方法能够有效地抑制原始信号的噪声干扰,对耦合的次/超同步振荡信号分解更加准确,参数辨识结果可靠性较高,对风电系统振荡溯源、改善系统阻尼具有一定的参考意义。
基金funded by the project of Guangdong Provincial Basic and Applied Basic Research Fund Committee(2022A1515240073)the Pearl River Talent Recruitment Program(2019CX01G338),Guangdong Province.
文摘Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.
基金supported by the National Natural Science Foundation of China(Nos.12341501 and 11905074)。
文摘Precise transverse emittance assessment in electron beams is crucial for advancing high-brightness beam injectors.As opposed to intricate methodologies that use specialized devices,quadrupole focusing strength scanning(Q-scanning)techniques offer notable advantages for various injectors owing to their inherent convenience and cost-effectiveness.However,their stringent approximation conditions lead to inevitable errors in practical operation,thereby limiting their widespread application.This study addressed these challenges by revisiting the analytical derivation procedure and investigating the effects of the underlying approximation conditions.Preliminary corrections were explored through a combination of data processing analysis and numerical simulations.Furthermore,based on theoretical derivations,virtual measurements using beam dynamics calculations were employed to evaluate the correction reliability.Subsequent experimental validations were performed at the Huazhong University of Science and Technology injector to verify the effectiveness of the proposed compensation method.Both the virtual and experimental results confirm the feasibility and reliability of the enhanced Q-scanning-based diagnosis for transverse emittance in typical beam injectors operating under common conditions.Through the integration of these corrections and compensations,enhanced Q-scanning-based techniques emerge as promising alternatives to traditional emittance diagnosis methods.
文摘This paper presents a high-fidelity lumpedparameter(LP)thermal model(HF-LPTM)for permanent magnet synchronous machines(PMSMs)in electric vehicle(EV)applications,where various cooling techniques are considered,including frame forced air/liquid cooling,oil jet cooling for endwinding,and rotor shaft cooling.To address the temperature misestimation in the LP thermal modelling due to assumptions of concentrated loss input and uniform heat flows,the developed HF-LPTM introduces two compensation thermal resistances for the winding and PM components,which are analytically derived from the multi-dimensional heat transfer equations and are robust against different load/thermal conditions.As validated by the finite element analysis method and experiments,the conventional LPTMs exhibit significant winding temperature deviations,while the proposed HF-LPTM can accurately predict both the midpoint and average temperatures.The developed HFLPTM is further used to assess the effectiveness of various cooling techniques under different scenarios,i.e.,steady-state thermal states under the rated load condition,and transient temperature profiles under city,freeway,and hybrid(city+freeway)driving cycles.Results indicate that no single cooling technique can maintain both winding and PM temperatures within safety limits.The combination of frame liquid cooling and oil jet cooling for end winding can sufficiently mitigate PMSM thermal stress in EV applications.
基金supported by the National Fund Cultivation Project from China People’s Police University(Grant Number:JJPY202402)National Natural Science Foundation of China(Grant Number:62172165).
文摘With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly progressed.This paper examines the advancements inDeepfake detection and defense technologies,emphasizing the shift from passive detection methods to proactive digital watermarking techniques.Passive detection methods,which involve extracting features from images or videos to identify forgeries,encounter challenges such as poor performance against unknown manipulation techniques and susceptibility to counter-forensic tactics.In contrast,proactive digital watermarking techniques embed specificmarkers into images or videos,facilitating real-time detection and traceability,thereby providing a preemptive defense againstDeepfake content.We offer a comprehensive analysis of digitalwatermarking-based forensic techniques,discussing their advantages over passivemethods and highlighting four key benefits:real-time detection,embedded defense,resistance to tampering,and provision of legal evidence.Additionally,the paper identifies gaps in the literature concerning proactive forensic techniques and suggests future research directions,including cross-domain watermarking and adaptive watermarking strategies.By systematically classifying and comparing existing techniques,this review aims to contribute valuable insights for the development of more effective proactive defense strategies in Deepfake forensics.
文摘电磁矢量传感器多输入多输出(electromagnetic vector sensor multiple-input multiple-output,EMVS-MIMO)雷达是一种新兴技术,可实现二维波达角(2D-DOA)估计。针对单基地稀疏阵列EMVS-MIMO雷达,提出一种基于旋转不变性信号参数估计技术ESPRIT(estimation of signal parameters via rotational invariance techniques)的降复杂度(reduced-complexity,RC)信号参数估计算法,能够实现对目标2D-DOA的快速估计。首先,对接收阵列数据进行RC处理,以消除阵列冗余数据;其次,利用ESPRIT可获得高分辨率的俯仰角估计,由于阵列的稀疏性,该估计值具有模糊性;再次,利用矢量叉积技术获得具有无模糊特性的2D-DOA;最后,利用无模糊的俯仰角估计对有周期模糊的估计进行解模糊,获得具有高分辨率、无模糊特性的俯仰角估计。该算法适用于大规模EMVS-MIMO雷达系统,且相比现有的ESPRIT-Like算法拥有更高的估计精度,通过MATLAB仿真验证了算法的有效性。
基金Supported by the National Natural Science Foundation of China(42474239,41204128)China National Space Administration(Pre-research project on Civil Aerospace Technologies No.D010301)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA17010303)。
文摘One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.
文摘Despite advancements in neuroimaging,false positive diagnoses of intracranial aneurysms remain a significant concern.This article examines the causes,prevalence,and implications of such false-positive diagnoses.We discuss how conditions like arterial occlusion with vascular stump formation and infundibular widening can mimic aneurysms,particularly in the anterior circulation.The article compares various imaging modalities,including computer tomography angiogram,magnetic resonance imaging/angiography,and digital subtraction angiogram,highlighting their strengths and limitations.We emphasize the im-portance of accurate differentiation to avoid unnecessary surgical interventions.The potential of emerging technologies,such as high-resolution vessel wall ima-ging and deep neural networks for automated detection,is explored as promising avenues for improving diagnostic accuracy.This manuscript underscores the need for continued research and clinical vigilance in the diagnosis of intracranial aneurysms.
基金National Key Research and Development Program(2021YFB3401101)。
文摘Short process forming techniques for brazing and soldering materials can shorten the process,improve product quality,and increase production efficiency,which has received much attention from welding researchers.This review mainly summarized the research reports on short process forming techniques for brazing and soldering materials.Firstly,the traditional process and its shortcomings were presented.Secondly,the latest research of short process forming technologies,such as continuous casting technique,atomization powder technique,solder ball forming technique,and rapid solidification technique,was summarized,and the traditional forming performance of several brazing and soldering materials was introduced.Finally,the current restrictions and research trends of short process forming technique for brazing and solder materials were put forward,providing theoretical guidance and reference for related research and technique development in brazing and soldering field.
文摘Low-voltage direct current(DC)microgrids have recently emerged as a promising and viable alternative to traditional alternating cur-rent(AC)microgrids,offering numerous advantages.Consequently,researchers are exploring the potential of DC microgrids across var-ious configurations.However,despite the sustainability and accuracy offered by DC microgrids,they pose various challenges when integrated into modern power distribution systems.Among these challenges,fault diagnosis holds significant importance.Rapid fault detection in DC microgrids is essential to maintain stability and ensure an uninterrupted power supply to critical loads.A primary chal-lenge is the lack of standards and guidelines for the protection and safety of DC microgrids,including fault detection,location,and clear-ing procedures for both grid-connected and islanded modes.In response,this study presents a brief overview of various approaches for protecting DC microgrids.
基金Supported by National Natural Science Foundation of China,No.82202694Clinical Research Innovation Plan of Shanghai General Hospital,No.CTCCR-2021C10.
文摘BACKGROUND Uniportal full-endoscopy(UFE)technique has been continuously developed and applied for treating lumbar spinal stenosis.However,achieving effective decompression outcome of using the UFE technique remains technically demanding and uncertain.Previously,we have proposed the biportal full-endoscopy(BFE)technique to integrate the respective advantages of both UFE and unilateral biportal endoscopy technique.There is limited published data on the comparison of clinical outcomes between biportal and UFE techniques in lumbar spinal stenosis with bilateral symptoms.AIM To contrast the clinical outcomes between biportal and UFE techniques for treating lumbar spinal stenosis with bilateral symptoms.METHODS This study retrospectively examined 100 patients diagnosed with lumbar spinal stenosis and bilateral symptoms.Among them,52 cases were part of group A(BFE technique group),and 48 cases belonged to group B(UFE technique group).The visual analogue scale(VAS),Oswestry Disability Index(ODI),and modified Macnab criteria were used to evaluate the clinical outcomes.RESULTS Group A had significantly shorter operation time than group B.Both groups experienced substantial relief in lower back and lower extremity pain on the severe side at postoperative 3 days,3 months,and 12 months.Group A had notably lower VAS scores for mild side lower extremity pain at postoperative 3 months and 12 months compared to group B.Group A's ODI scores were significantly lower at postoperative 3 months and 12 months,whereas group B's scores did not significantly differ from preoperative values.Group A's ODI scores were significantly lower than group B's at postoperative 3 months and 12 months.Group A had a significantly higher excellent and good response rate(94.23%)compared to group B(81.25%)at postoperative 12 months based on the modified Macnab scale outcomes.CONCLUSION The BFE technique offers multiple benefits,including reduced trauma and quicker recovery as a minimally invasive surgery,and enhanced decompression efficiency over the UFE technique when treating lumbar spinal stenosis with bilateral symptoms.
文摘Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in different database repositories every day. Most of the review data are useful to new customers for theier further purchases as well as existing companies to view customers feedback about various products. Data Mining and Machine Leaning techniques are familiar to analyse such kind of data to visualise and know the potential use of the purchased items through online. The customers are making quality of products through their sentiments about the purchased items from different online companies. In this research work, it is analysed sentiments of Headphone review data, which is collected from online repositories. For the analysis of Headphone review data, some of the Machine Learning techniques like Support Vector Machines, Naive Bayes, Decision Trees and Random Forest Algorithms and a Hybrid method are applied to find the quality via the customers’ sentiments. The accuracy and performance of the taken algorithms are also analysed based on the three types of sentiments such as positive, negative and neutral.
文摘Objectives:The objective of this study was to assess the impact of two relaxation techniques,the Jacobson’s progressive muscle relaxation technique(JPMR),and the Benson’s relaxation technique(BRT),on the levels of stress and anxiety experienced by patients undergoing coronary angioplasty.Materials and Methods:Quantitative research approach with quasi-experimental pre-test and posttest control group design was conducted with seventy coronary angioplasty patients from the Institute of Medical Science,and SUM Hospital,Bhubaneswar,Odisha.The participants were purposively selected and divided into Experimental Group 1(n=35)and Experimental Group 2(n=35).Each group received either BRT or JPMR for three consecutive days.Pretest and posttest data were collected using a structured demographic questionnaire and the modified depression anxiety stress scale-21.Results:Both BRT and JPMR significantly decreased the levels of stress and anxiety among patients undergoing angioplasty compared to baseline(P<0.05).However,there was no significant difference between the two techniques based on Fisher’s exact P value.This suggests that both interventions are effective in reducing stress and anxiety among angioplasty patients.Conclusion:BRT or JPMR are noninvasive,nonpharmacological interventions that effectively reduce stress and anxiety in patients undergoing angioplasty.These findings underscore the importance of incorporating relaxation techniques into nursing practice and hospital programs to enhance patient care and promote holistic well-being post-angioplasty.
基金Supported by the Fuyang Normal University-Fuyang City Local Cooperation Science and Technology Special Project(SXHZ202205).
文摘Wheat is one of the primary grain crops in China and is widely cultivated.Successful cultivation requires careful selection of varieties,seeding,fertilization,and pest control to ensure adequate nutrient absorption by roots and improve lodging resistance and disease tolerance.This study investigated the cultivation techniques of the wheat variety New Century 999,and examined its growth stage characteristics and cultivation requirements.The analysis identifies challenges in its cultivation and provides recommendations for pre-sowing preparation,land preparation,seeding,fertilization,and management practices in both winter and spring.
文摘Although legal liability is a key component of local regulations and ensures their effective implementation,existing research has paid insufficient attention to the techniques for setting legal liability clauses in the local legislation,due to a lack of systematic analysis.To address this gap,this paper employs the interview method to empirically examine the formation process,as well as the techniques for establishing legal liability in local legislation,with the aim of revealing the primary legislative techniques for formulating legal liability clauses in local legislation and their application principles.Drawing from these empirical findings and analytical insights,the research demonstrates that the legal liability-setting techniques in local legislation tend to exhibit a weak coherence with regard to logic and a strong policy orientation.These issues potentially create tension with the legal norms’demands for certainty,abstraction,and completeness.Therefore,this paper proposes a three-pronged framework to harmonize competing demands by respecting local particularities and achieving context-sensitive regulatory balance.This framework advocates that local legislative practice should(a)prioritize practical rationality and rule effectiveness over logical completeness,acknowledging inherent conflicts with traditional legislative models;(b)adopt a typological legislative method to balance normative principles with governance efficiency by transcending logic-experience binaries;and(c)establish a dynamic updating mechanism with regular evaluation to maintain adaptability to socio-economic evolution.
文摘Figure 3 in the paper[Chin.Phys.B 34020701(2025)]contains an axis labeling error.The revised figure is provided.This modification does not affect the result presented in the paper.
