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IEC 62368-1《音视频、信息技术和通信技术设备第1部分:安全要求》第四版的主要技术更新解析

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中国标准化 2024年第2期 128-135页

作者：姚青梅高岭松徐永生赵羽声中家院(北京)检测认证有限公司北京泰瑞特检测技术服务有限责任公司

GB4943.1-2022《音视频、信息技术和通信技术设备第1部分:安全要求》修改采用了国际标准IEC62368-1:2018第三版,2023年5月国际电工委员会(IEC)发布了IEC 62368-1:2023 (第四版),在第三版的基础上进行了技术方法升级改进,澄清或替代了第... 详细信息

GB4943.1-2022《音视频、信息技术和通信技术设备第1部分:安全要求》修改采用了国际标准IEC62368-1:2018第三版,2023年5月国际电工委员会(IEC)发布了IEC 62368-1:2023 (第四版),在第三版的基础上进行了技术方法升级改进,澄清或替代了第三版中的一些要求。本文从结构和元器件要求、电能量源要求和着火方面等11个方面对这些更新的技术要求和测试方法进行解析,可看出第四版标准的适用性更强,顺应了当前技术产业发展趋势。

关键词：增加更新安全防护测试评估要求

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Medical comorbidities at admission is predictive for 30-day in-hospital mortality in patients with acute myocardial infarction： analysis of 5161 cases

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Journal of Geriatric Cardiology 2011年第1期8卷 31-34页

作者： Xue-Dong Yang yu-sheng zhao yu-Feng Li Xin-Hong Guo Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

Background The present study investigated the prognostic value of medical comorbidities at admission for 30-day in-hospital mortality in patients with acute myocardial infarction （AMI）. Methods A total of 5161 patients with AMI were admitted in Chinese PLA General Hospital between January 1, 1993 and December 31, 2007. Medical comorbidities including hypertension, diabetes mellitus, previous myocardial infarction, valvular heart disease, chronic obstructive pulmonary disease （COPD）, renal insufficiency, previous stroke, atrial fibrillation and anemia, were identified at admission. The patients were divided into 4 groups based on the number of medical comorbidities at admission （0, 1, 2, and ≥3）. Cox regression analysis was used to calculate relative risk （RR） and 95% confidence intervals （CI）, with adjustment for age, sex, heart failure and percutaneous coronary intervention （PCI）. Results The mean age of the studied population was 63.9 ± 13.6 years, and 80.1% of the patients were male. In 74.6% of the patients at least one comorbidity were identified. Hypertension （50.7%）, diabetes mellitus （24.0%） and previous myocardial infarction （12%） were the leading common comorbidities at admission. The 30-day in-hospital mortality in patients with 0, 1, 2, and ≥3 comorbidities at admission （7.2%） was 4.9%, 7.2%, 11.1%, and 20.3%, respectively. The presence of 2 or more comorbidities was associated with higher 30-day in-hospital mortality compared with patients without comorbidity （RR： 1.41, 95% CI： 1.13-1.77, P = 0.003, and RR： 1.95, 95% CI： 1.59-2.39, P = 0.000, respectively）. Conclusions Medical comorbidities were frequently found in patients with AMI. AMI patients with more comorbidities had a higher 30-day in-hospital mortality might be predictive of early poor outcome in patients with AMI.

关键词： acute myocardial infarction comorbidity mortality

Brachial-ankle pulse wave velocity is an independent predictor of carotid artery atherosclerosis in the elderly

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Journal of Geriatric Cardiology 2010年第3期7卷 157-160页

作者： Jia-yue Li yu-sheng zhao Institute of Geriatric Cardiology Chinese PLA General HospitaLBeijing 100853 China

Objective Brachial-ankle pulse wave velocity （baPWV） is widely used as a simple noninvasive measure of arterial softness. The aim of this study was to evaluate the usefulness of baPWV as a predictor of the carotid artery atherosclerosis in the elderly. Methods A total of 721 elderly participants （mean ~ SD age, 70.3 -4- 5.6years） were enrolled in the current study. All participant underwent both baPWV measurement and B-mode ultrasound for the intima-media thickness. Carotid atherosclerosis （CAS） was defined as the present of carotid plaque or and/or intima media thickness for at least 1.1 mm. Results A multivariate logistic regression analysis reveals that age, sex, brachial-ankle pulse wave velocity, smoking and LDL-C level showed a significant correlation with the presence of CAS. The odds ratios of CAS associated with a 500cm/s increase of brachial-ankle pulse wave velocity were 2.378 [95% confidence interval, 1.36 to 4.00, P〈0.05], 3.733 [95% confidence interval, 1.729 to 8.058, P〈0.01], 4.438 [95% confidence interval, 1.659 to 11.803, P〈0.01]. The baPWV significantly correlated with IMT by bivariate correlation analysis （r=-0.39; p=0.001）. After adjusting for factors influencing, baPWV all the same correlated with IMT （r=-0.35; p=0.001）.Conclusion These results indicate that brachial-ankle PWV is an independent predictor of CAS in the *** also means that the direct measurement of arterial stiffness by this simple method may be of great help for the evaluation of carotid artherosclerosis, at least in the elderly

关键词： Aortic stiffness carotid arteriosclerosis pulse wave velocity

FULLY RESOLVED NUMERICAL SIMULATION OF TURBULENT PIPE FLOWS LADEN WITH LARGE NEUTRALLY-BUOYANT PARTICLES

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Journal of Hydrodynamics 2011年第1期23卷 21-25页

作者： WU Teng-hu SHAO Xue-ming yu zhao-sheng State Key Laboratory of Fluid Power Transmission and Control Department of Mechanics Zhejiang UniversityHangzhou 310027 China

In this article,we employ a fully-resolved numerical simulation method（the fictitious domain method）to investigate the effects of large neutrally-buoyant particles on the turbulent flow in a pipe at low Reynolds number and non-dilute *** tube Reynolds number is fixed to be 4 900,the particle-pipe diameter ratio is 0.1,and the particle volume fraction ranges from 0.33%to 10%.Our results indicate that the presence of large particles decreases the maximum root-of-mean-square（rms）of the streamwise velocity fluctuation near the wall by weakening the intensity of large-scale streamwise vortices,although in the region very close to the wall the particles increase the rms of streamwise velocity *** the other hand,the particles induce small-scale vortices in the near-wall region,resulting in the enhancement of the rms of radial and circumferential velocity fluctuations there.

关键词： fully-resolved direct numerical solution particulate turbulent pipe flow large particles particle-turbulence interactions

THREE-DIMENSIONAL PAIRING OF COHERENT STRUCTURES IN A PLANE MIXING LAYER

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Journal of Hydrodynamics 2002年第2期14卷 1-6页

作者： Lin, Jian-Zhong Shi, Xing yu, zhao-sheng Shao, Xue-Ming Dept. of Mech. Lab. of Fluid Power Trans. Zhejiang Univ. Hangzhou 310027 China

The three-dimensional (3D) pairing process of coherent structures in a plane mixing layer was simulated numerically with the pseudo-spectral method. The behaviors of spanwise cup-shaped vortices, streamwise rib-shaped vortices and quadrupoles were obtained in terms of their iso-surfaces. The results show that three-dimensional structures are strongly influenced by the initial amplitude of the 3D disturbance, and that in most cases the local pairing finishes in a roughly two-dimensional manner. In pairing region, the streamwise vortices are chaotic after pairing due to the breakdown of the engulfed ribs and especially the subsequent breakdown of the quadrupoles. The surviving ribs extend to the top (or bottom) of the paired vortices under the stretch of them. In addition, it is revealed that three dimensional vortices pairing can enhance the mixing of fluid. Finally, some patterns of numerical flow visualization are presented by computing the passive scalar.

关键词： Flow of fluids Flow visualization Mixing Numerical analysis Three dimensional

New model of linkage evolution for the transtensional fault systems in the Nanpu Sag of Bohai Bay Basin: Insight from seismic interpretation and analogue modelling

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Petroleum Science 2024年第4期21卷 2287-2310页

作者： yu-Heng Wang Fu-sheng yu Bao-Yin zhao Ling-Jian Meng College of Geosciences China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum (Beijing) Jidong Oilfield Company PetroChina Limited Company

The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures, stress transmission through ductile detachment layers, and the growth, interaction, as well as linkage of new fault segments. This study analyses a complex multi-phase oblique extension fault system in the Nanpu Sag(NPS) of the Bohai Bay Basin(BBB),China. High-resolution three-dimensional(3D) seismic data and analogue modelling indicate that the oblique extensional reactivation of pre-existing structures governs the sequential arrangement of fault segments in the caprock, and they dip synthetically to the reactivated fault at depth. During the NW-SE extension in the Eocene, the predominant movement of the pre-existing fault is strike-slip. Subsequently,during the N-S extension since the Oligocene, inclined at *** the pre-existing fault, forming splay fault segments and ultimately creating large en-echelon arcuate faults linked by relay ramps. Using fault throw-distance(T-D) and laser scanning, we reconstructed the fault evolution model of oblique extension reactivation in the presence of a ductile detachment basement. Our study illustrates that the arcuate faults can be categorized into linear master fault segments controlled by pre-existing structures, bending splay faults in the termination zone, and normal fault segments responding to the regional stress *** interaction between faults occurs among normal faults and strike-slip faults, and the kinematic unification of the two fault systems is accomplished in the intersection zone. As the faults continue to evolve, the new fault segments tend to relinquish the control of pre-existing structures and concentrate more on the development of planar and continuous major faults. The ductile detachment layer significantly contributes to the uniform distribution of strain, resulting in narrow shear zones and discontinuous normal faults in its absence.

关键词： Analogue modelling Transtensional deformation Fault linkage Fault intersection zone Nanpu Sag of Bohai Bay basin

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： sheng-wen Xu Shi-yu Dai Teng zhao Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： yu-Ning Yong zhao-Quan Guo Shou-Ceng Tian Lu-Yao Ma Tian-yu Wang Mao sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Wheat 14-3-3 Protein Conferring Growth Retardation in Arabidopsis

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Journal of Integrative Agriculture 2013年第2期12卷 209-217页

作者： LI Jing SONG Su-sheng zhao yu-sheng GUO Wei-wei GUO Guang-hui PENG Hui-ru NI Zhong-fu SUN Qi-xin YAO Ying-yin State Key Laboratory for Agrobiotechnology and Key Laboratory of Crop Heterosis and Utilization Minstry of Education/Key Laboratory of Crop Genomics and Genetic Improvement Minstry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University School of Life Sciences Tsinghua University

14-3-3 proteins belong to a family of phosphoserine/threonine-binding modules and participate in a wide array of signal transduction and regulatory events. Our previous study demonstrated that Ta14-3-3 was significantly down-regulated in leaf and root tissues of hybrid wheat at the tillering stage. In this paper, three homoeologous Ta14-3-3 genes were cloned from common wheat （Triticum aestivum L., 2n=6x=42, AABBDD） and mapped on chromosomes 2A, 2B, and 2D, respectively. Transgenic Arabidopsis plants ectopically overexpressing Ta14-3-3 displayed shorter primary roots, delayed flowering and retarded growth rates, indicating that Ta14-3-3 acted as a growth inhibitor in Arabidopsis. In wheat, Ta14-3-3 was down-regulated in roots and leaves of hybrids as compared to their parental lines. We proposed that Ta14-3-3 proteins might regulate growth vigor in hybrid wheat.

关键词： wheat Ta14-3-3 heterosis gene expression