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Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 234-244页

作者： Jun-Yu Shen Bi-Wen bao Li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of Statistical Modeling and Data Analysis of Yunnan Province Yunnan UniversityKunming 650091China

Using an effective adiabatic index γ_(eff) to mimic the feedback of efficient shock acceleration,we simulate the temporal evolution of a young type Ia supernova remnant (SNR) with two different background magnetic field(BMF) topologies:a uniform and a turbulent *** density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic *** γ_(eff)is considered,we find that:(1) the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;(2) there exists more quasi-radial magnetic fields inside the shocked region;and (3) inside the intershock region,both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction,with γ_(eff)=1.1,they are amplified about 10–26 times more than those with γ_(eff)=5/*** in the angular direction,the total magnetic energy densities could be amplified about 350 times more than those with γ_(eff)=5/3,and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： methods:numerical ISM:magnetic fields ISM:supernova remnants magnetohydrodynamics(MHD)

Online estimation and characteristic analysis of double nugget diameters during aluminum/steel resistance spot welding process

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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang Zhou Wen-xiao Yu bao-kai Ren Gang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

Review of tribological properties of nanoparticle-based lubricants and their hybrids and composites

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Friction 2024年第4期12卷 569-590页

作者： Ye Zar Ni HTWE Aws.S.AL-JANABI Yasmin WADZER Hussin MAMAT ku NOORYASMIN School of Materials&Mineral Resources Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia School of Aerospace Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia Universiti Sains Malaysia

Due to their encouraging results,nanolubricants have been revolutionary in the field of *** degree,to which the new material may improve the tribology,energy savings,and durability,is a crucial consideration for any new additive to a conventional *** results of the earlier research on carbon,metal,metal oxide,and their composites and hybrid nanolubricants as well as their effects on tribology,are summarized in this review *** most popular measuring methodologies,the tribology results for lubricants with an oil base,biodegradable base,and a water base,as well as the reasons that explain these tribological advancements,are all included in this ***,prospects for more study in this area are emphasized.

关键词： nanolubricants tribology carbon metal metal oxide hybrid

Will the Globe Encounter the Warmest Winter after the Hottest Summer in 2023?

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Advances in Atmospheric Sciences 2024年第4期41卷 581-586页

作者： Fei ZHENG Shuai HU Jiehua MA Lin WANG Kexin LI Bo WU Qing bao Jingbei PENG Chaofan LI Haifeng ZONG Yao YAO baoqiang TIAN Hong CHEN Xianmei LANG Fangxing FAN Xiao DONG Yanling ZHAN Tao zhu Tianjun ZHOU Jiang zhu International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nansen-zhu International Research Centre(NZC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Center for Monsoon System Research(CMSR) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China CAS Key Lab of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

In the boreal summer and autumn of 2023,the globe experienced an extremely hot period across both oceans and *** consecutive record-breaking mean surface temperature has caused many to speculate upon how the global temperature will evolve in the coming 2023/24 boreal *** this report,as shown in the multi-model ensemble mean(MME)prediction released by the Institute of Atmospheric Physics at the Chinese Academy of Sciences,a medium-to-strong eastern Pacific El Niño event will reach its mature phase in the following 2−3 months,which tends to excite an anomalous anticyclone over the western North Pacific and the Pacific-North American teleconnection,thus serving to modulate the winter climate in East Asia and North *** some uncertainty due to unpredictable internal atmospheric variability,the global mean surface temperature(GMST)in the 2023/24 winter will likely be the warmest in recorded history as a consequence of both the El Niño event and the long-term global warming ***,the middle and low latitudes of Eurasia are expected to experience an anomalously warm winter,and the surface air temperature anomaly in China will likely exceed 2.4 standard deviations above climatology and subsequently be recorded as the warmest winter since ***,the necessary early warnings are still reliable in the timely updated mediumterm numerical weather forecasts and sub-seasonal-to-seasonal prediction.

关键词： winter climate El Niño seasonal forecast GMST

Efficacy of Chinese Medicine Treatment Based on Syndrome Differentiation for Primary Insomnia:A Randomized Placebo Controlled Triple-Blinded Trial

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Chinese Journal of Integrative Medicine 2024年第10期30卷 867-876页

作者： XIONG Zhi-yi LU Ying HE Li-yun ZHANG Run-shun ZHOU Xue-zhong LI Peng LIU Yan-jiao zhu Jian-gui YAN Shi-yan LIU bao-yan International Acupuncture and Moxibustion Innovation Institute School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese Medicine Department of Biomedical Data Science Stanford University School of Medicine Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical Sciences Guang'anmen Hospital China Academy of Chinese Medical Sciences Beijing Jiaotong University School of Computer and Information Technology Beijing Xicheng District Community Healthcare Center China Academy of Chinese Medical Sciences

Objective: To assess efficacy of Chinese medicine(CM) on insomnia considering characteristics of treatment based on syndrome differentiation. Methods: A total of 116 participants aged 18 to 65 years with moderate and severe primary insomnia were randomized to the placebo(n=20) or the CM group(n=96) for a 4-week treatment and a 4-week follow-up. Three CM clinicians independently prescribed treatments for each patient based on syndromes differentiation. The primary outcome was change in total sleep time(TST) from baseline. Secondary endpoints included sleep onset latency(SOL), wake time after sleep onset(WASO), sleep efficiency, Pittsburgh Sleep Quality Index(PSQI) and CM symptoms. Results: The CM group had an average 0.6 h more(95% confidence interval(CI): 0.3–0.9, P<0.001) TST and 34.1%(10.3%–58.0%, P=0.005) more patients beyond 0.5 h TST increment than that of the placebo group. PSQI was changed –3.3(–3.8 to –2.7) in the CM group, a –2.0(–3.2 to –0.8, P<0.001) difference from the placebo group. The CM symptom score in the CM group decreased –2.0(–3.3 to –0.7, P=0.003) more than the placebo group. SOL and WASO changes were not significantly different between groups. The analysis of prescriptions by these clinicians revealed blood deficiency and Liver stagnation as the most common syndromes. Prescriptions for these clinicians displayed relative stability, while the herbs varied. All adverse events were mild and were not related to study treatment. Conclusions: CM treatment based on syndrome differentiation can increase TST and improve sleep quality of primary insomnia. It is effective and safe for primary insomnia. In future studies, the long-term efficacy validation and the exploratory of eutherapeutic clinicians' fixed herb formulas should be addressed.(Registration No. NCT01613183)

关键词： Chinese medicine primary insomnia randomized controlled trial syndrome differentiation

Electron beam lithography on nonplanar and irregular surfaces

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Microsystems & Nanoengineering 2024年第2期10卷 1-23页

作者： Chenxu zhu Huseyin Ekinci Aixi Pan Bo Cui Xiaoli zhu Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology(WIN) University of WaterlooWaterlooONCanada

E-beam lithography is a powerful tool for generating nanostructures and fabricating nanodevices with fine features approaching a few nanometers in ***,alternative approaches to conventional spin coating and development processes are required to optimize the lithography procedure on irregular *** this review,we summarize the state of the art in nanofabrication on irregular substrates using e-beam *** overcome these challenges,unconventional methods have been *** instance,polymeric and nonpolymeric materials can be sprayed or evaporated to form uniform layers of electron-sensitive materials on irregular ***,chemical bonds can be applied to help form polymer brushes or self-assembled monolayers on these *** addition,thermal oxides can serve as resists,as the etching rate in solution changes after e-beam ***,e-beam lithography tools can be combined with cryostages,evaporation systems,and metal deposition chambers for sample development and lift-off while maintaining low *** nanopyramids can be fabricated on an AFM tip by utilizing ice as a positive ***,Ti/Au caps can be patterned around a carbon ***,3D nanostructures can be formed on irregular surfaces by exposing layers of anisole on organic ice surfaces with a focused *** advances in e-beam lithography on irregular substrates,including uniform film coating,instrumentation improvement,and new pattern transferring method development,substantially extend its capabilities in the fabrication and application of nanoscale structures.

关键词： lithography beam coating

Chinese version of the Perth Alexithymia Questionnaire:psychometric properties and clinical applications

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General Psychiatry 2024年第2期37卷 274-283页

作者： Xin-Lu Cai Qingying Ye Ke Ni Lin zhu Qian Zhang Minmin Yin Zhe Zhang Wei Wei David A.Preece bao-Ming Li Institute of Brain Science and Department of Physiology School of Basic Medical SciencesHangzhou Normal UniversityHangzhouZhejiangChina Zhejiang Philosophy and Social Science Laboratory for Research in Early Development and Childcare Hangzhou Normal UniversityHangzhouZhejiangChina Qiqihar Mental Health Center QiqiharChina Department of Special Education Faculty of EducationHangzhou Normal UniversityHangzhouZhejiangChina Department of Neurobiology Affiliated Mental Health Center&Hangzhou Seventh People's Hospital Zhejiang University School of MedicineHangzhouZhejiangChina Liangzhu Laboratory MOE Frontier Science Center for Brain Science and Brain-machine IntegrationState Key Laboratory of Brain-machine IntelligenceZhejiang UniversityHangzhouZhejiangChina NHC and CAMS Key Laboratory of Medical Neurobiology Zhejiang UniversityHangzhouChina School of Population Health and Curtin enAble Institute Curtin UniversityPerthWestern AustraliaAustralia School of Psychological ScienceThe University of Western AustraliaPerthWestern AustraliaAustralia

Background The alexithymia trait is of high clinical *** Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of *** In this paper,we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical *** In Study 1,the PAQ was administered to 990 Chinese *** examined its factor structure,internal consistency,test-retest reliability,as well as convergent,concurrent and discriminant *** Study 2,four groups,including a major depressive disorder(MDD)group(n=50),a matched healthy control group for MDD(n=50),a subclinical depression group(n=50)and a matched healthy control group for subclinical depression(n=50),were *** comparisons were conducted to assess the clinical relevance of the *** In Study 1,the intended five-factor structure of the PAQ was found to fit the data *** PAQ showed good internal consistency and test-retest reliability,as well as good convergent,concurrent and discriminant *** Study 2,the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy *** The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression.

关键词： clinical instrument matched

A pregnant patient with type II osteogenesis imperfecta pregnancy

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World Journal of Emergency Medicine 2024年第1期15卷 75-76页

作者： Chenyu Jiang Chenyi bao Shujuan Shu Department of Obstetrics Women’s HospitalSchool of MedicineZhejiang UniversityHangzhou 310006China

Osteogenesis imperfecta(OI)is a primary bone fragility disorder with an estimated prevalence of 1/15,000 births and is a hereditary syndrome characterized by one or more of the following:fractures,blue sclerae,impaired hearing,defective dentition,and hyperlaxibility throughout life.[1,2]We report a pregnant woman with type II OI and review her prenatal counseling,diagnosis,and pregnancy management to assist obstetricians in understanding the disease and managing it in emergency situations.

关键词： pregnancy impaired diagnosis

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu Wen-Jin Niu Ye zhu Hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)