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Existence, morphology and structure of the Yellow Sea Warm Current Branch approaching waters offshore Qingdao, China
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作者 Xuejun XIONG Xiaomin HU +3 位作者 Yanliang GUO Long YU Liang CHEN Yuhuan XUE 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第7期1167-1180,共14页
In this study, we focused on full-region cruise survey data, near-bottom continuous mooring observations and sea surface wind products from the western South Yellow Sea in winter; after ensuring the data reliability a... In this study, we focused on full-region cruise survey data, near-bottom continuous mooring observations and sea surface wind products from the western South Yellow Sea in winter; after ensuring the data reliability and accuracy, we processed and analyzed the data. Image resolution experiments were carried out to determine the lowest recognition resolutions for all image types, which represent the resolution characteristics of the data. The existence of a warm water tongue originating from the Yellow Sea Warm Current(YSWC) that approached waters offshore Qingdao was confirmed. For the first time, a high salinity water tongue, corresponding to the warm water tongue, was described and found to be more representative of the YSWC branch path. This warm tongue is a sign of the branch originating from the YSWC, which we defined as the Yellow Sea Warm Current Branch approaching waters offshore Qingdao(YSWC-QDB). The pattern of the warm and salty water tongues showed remarkable rear, branching middle, shrinking neck and expanding top regions. These patterns showed a temporal feature of the tongues, and were the result of multi-temporal branches in front of the YSWC main section as well as the YSWC-QDB crossing the southwestward path of the extension of the North Shandong Coastal Current flowing along the southeast coast of the Shandong Peninsula(NSCC-SESE). Analysis using mooring data at a sensitive and representative station also showed the existence of the YSWC-QDB. It is a probabilistic event that manifests as a northwestward flow that decreases gradually from the bottom to the surface in the early cold air transit stage and consistent in the whole water column profile in the later stage. It varies quasi-periodically with weather processes. It also transports some of the YSWC water stored in the entrance area of the Bohai and Yellow seas under winter wind conditions to the western South Yellow Sea as a compensatory current. This current, caused by northerly winds, especially northwest winds and obstruction of the NSCC 展开更多
关键词 Yellow Sea Warm CURRENT Branch APPROACHING WATERS OFFSHORE Qingdao (YSWC-QDB) High salinity water tongue Compensatory CURRENT Strong northwest wind Extension of the North SHANDONG Coastal CURRENT flowing along the southeast coast of the SHANDONG Peninsula (NSCC-SESE) EXISTENCE confirmation Morphology Structure
Current-limiting characteristics of saturated iron-core fault current limiters in VSC-HVDC systems based on electromagnetic energy conversion mechanism 预览
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作者 Botong LI Hanqing CUI +2 位作者 Fangjie JING Bin LI Yichao LIU 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第2期412-421,共10页
A common method to examine the current-limiting performance of saturated iron-core fault current limiter(SI-FCL) in high-voltage direct-current transmission based on voltage source converter(VSC-HVDC) systems is to so... A common method to examine the current-limiting performance of saturated iron-core fault current limiter(SI-FCL) in high-voltage direct-current transmission based on voltage source converter(VSC-HVDC) systems is to solve differential equations based on the system fault transient characteristics and the equivalent inductance calculation equation. This method analyzes the fault current of the VSC-HVDC system in the time domain. However, it is computationally complex and cannot directly reflect the relationship between parameters and the currentlimiting effect of the SI-FCL.In this paper,the relationship between the magnetic flux density and magnetic field energy of the SI-FCL is analyzed. The energy exchange between the DC capacitor and the SI-FCL in the DC short circuit fault process is analyzed. From the perspective of electromagnetic energy conversion, the criterion for determining the current-limiting ability of the SI-FCL in the transient process is given based on the parameters of the SI-FCL and VSC-HVDC system. On this basis, the characteristics of the DC side fault current and the capacitor voltage when the SI-FCL has current-limiting ability are examined.Based on the parameters of the SI-FCL and VSC-HVDC system, a method for calculating the fault current peak value and capacitor voltage drop time is given. Finally, the accuracy of the analysis of the SI-FCL in the VSC-HVDC system based on the electromagnetic energy conversion mechanism is demonstrated through a case study and simulation results of the VSC-HVDC system with different SI-FCLs. 展开更多
关键词 ELECTROMAGNETIC energy Saturated iron-core FAULT current limiter(SI-FCL) HIGH-VOLTAGE direct-current transmission based on voltage source converter(VSCHVDC) system FAULT analysis
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Current Model Analysis of South China Sea Based on Empirical Orthogonal Function(EOF)Decomposition and Prototype Monitoring Data 预览
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作者 WU Wenhua LIU Ming +1 位作者 YU Siyuan WANG Yanlin 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期305-316,共12页
Environmental load is the primary factor in the design of offshore engineering structures and ocean current is the principal environmental load that causes underwater structural failure.In computational analysis,the c... Environmental load is the primary factor in the design of offshore engineering structures and ocean current is the principal environmental load that causes underwater structural failure.In computational analysis,the calculation of current load is mainly based on the current profile.The current profile model,which is based on a structural failure criterion,is conducive to decreasing the uncertainty of the current load.In this study,we used prototype monitoring data and the empirical orthogonal function(EOF)method to investigate the current profile in the South China Sea and its correlation with the design of underwater structural strength and the dynamic design of fatigue.The underwater structural strength design takes into account the size of the structure and the service water depth.We propose profiles for the overall and local designs using the inverse first-order reliability method(IFORM).We extracted the characteristic profile current(CPC)of the monitored sea area to solve dynamic design problems such as vortex-induced vibration(VIV).We used random sampling to verify the feasibility of using the EOF method to calculate the CPC from the current data and identified the main problems associated with using the CPC,which deserve close attention in VIV design.Our research conclusions provide direct references for determining current load in this sea area.This analysis method can also be used in the analysis of other sea areas or field variables. 展开更多
关键词 CURRENT PROFILE model failure criteria PROTOTYPE monitoring inverse FIRST-ORDER reliability method(IFORM) Characteristic PROFILE current(CPC)
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鲁海丰海洋牧场流场特征分析 预览
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作者 刘鹏霞 刘子洲 +3 位作者 宋新 顾艳镇 翟方国 李培良 《中国海洋大学学报:自然科学版》 CAS CSCD 北大核心 2019年第8期10-18,共9页
根据海底有缆观测系统连续观测得到的3个半月的海水流矢量资料,利用功率谱分析、调和分析、旋转谱分析和相关分析等方法研究了鲁海丰海洋牧场海域海流的时间变化规律和空间结构特征。主要结论如下:在整个水体厚度上,西北向流占优,呈现... 根据海底有缆观测系统连续观测得到的3个半月的海水流矢量资料,利用功率谱分析、调和分析、旋转谱分析和相关分析等方法研究了鲁海丰海洋牧场海域海流的时间变化规律和空间结构特征。主要结论如下:在整个水体厚度上,西北向流占优,呈现出向岸流的特点,且由表及底,西向流减弱,北向流增强;潮流类型为正规半日潮,M2分潮流为主,各层主要分潮流均表现为以逆时针方向旋转为主的往复运动,总体上观测点的日周期波动只由全日潮流引起,不受当地惯性流影响。此外观测点处的流还表现出更高频的波动周期;鲁海丰海洋牧场的表层余流主要由海面风场驱动,同时也受到山东半岛沿岸流的影响。 展开更多
关键词 海洋牧场 海流 调和分析 旋转谱 余流
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Numerical modeling of lock-exchange gravity/turbidity currents by a high-order upwinding combined compact difference scheme 预览
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作者 Liang Zhao Ching-Hao Yu Zhiguo He 《国际泥沙研究:英文版》 SCIE 2019年第3期240-250,共11页
This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including t... This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including the buoyancy force for the density difference between the light and heavy fluids are solved by a finite difference scheme based on a structured mesh.The concentration transport equations are used to explore such rich transport phenomena as gravity and turbidity currents.Within the framework of an Upwinding Combined Compact finite Difference(UCCD)scheme,rigorous determination of weighting coefficients underlies the modified equation analysis and the minimization of the numerical modified wavenumber.This sixth-order UCCD scheme is implemented in a four-point grid stencil to approximate advection and diffusion terms in the concentration transport equations and the first-order derivative terms in the Navier-Stokes equations,which can greatly enhance convective stability and increase dispersive accuracy at the same time.The initial discontinuous concentration field is smoothed by solving a newly proposed Heaviside function to prevent numerical instabilities and unreasonable concentration values.A two-step projection method is then applied to obtain the velocity field.The numerical algorithm shows a satisfying ability to capture the generation,development,and dissipation of the Kelvin-Helmholz instabilities and turbulent billows at the interface between the current and the ambient fluid.The simulation results also are compared with the data in published literatures and good agreements are found to prove that the present numerical model can well reproduce the propagation,particle deposition,and mixing processes of lock-exchange gravity and turbidity currents. 展开更多
关键词 GRAVITY CURRENT TURBIDITY CURRENT Depth-resolving mathematical model INCOMPRESSIBLE Navier-Stokes equations Upwinding COMBINED Compact Difference(UCCD) scheme
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Improving the data retention of phase change memory by using a doping element in selected Ge2Sb2Te5 预览
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作者 Yaoyao Lu Daolin Cai +5 位作者 Yifeng Chen Shuai Yan Lei Wu Yuanguang Liu Yang Li Zhitang Song 《半导体学报:英文版》 EI CAS CSCD 2019年第4期29-34,共6页
The crystallization characteristics of a ubiquitous T-shaped phase change memory (PCM) cell, under SET current pulse and very small disturb current pulse, have been investigated by finite element modelling. As analyze... The crystallization characteristics of a ubiquitous T-shaped phase change memory (PCM) cell, under SET current pulse and very small disturb current pulse, have been investigated by finite element modelling. As analyzed in this paper, the crystallization region under SET current pulse presents first on the corner of the bottom electron contact (BEC) and then promptly forms a filament shunting down the amorphous phase to achieve the low-resistance state, whereas the tiny disturb current pulse accelerates crystallization at the axis of symmetry in the phase change material. According to the different crystallization paths, a new structure of phase change material layer is proposed to improve the data retention for PCM without impeding SET operation. This structure only requires one or two additional process steps to dope nitrogen element in the center region of phase change material layer to increase the crystallization temperature in this confined region. The electrical-thermal characteristics of PCM cells with incremental doped radius have been analyzed and the best performance is presented when the doped radius is equal to the radius of the BEC. 展开更多
关键词 phase change memory CRYSTALLIZATION process SET CURRENT PULSE small disturb CURRENT PULSE finite ELEMENT simulation
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Experimental investigation on ablation characteristics of coated and uncoated steel under 30/80 μs impulse current
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作者 戴明秋 刘亚坤 +2 位作者 傅正财 刘娟 毕晓蕾 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第7期123-134,共12页
The ablation tests on coated and uncoated Q235 B steel sheets were conducted under 30/80 μs impulse current simulating the lightning first return stroke current, aimed at further understanding the ablation characteri... The ablation tests on coated and uncoated Q235 B steel sheets were conducted under 30/80 μs impulse current simulating the lightning first return stroke current, aimed at further understanding the ablation characteristics of steel and investigating the impact of anti-corrosion coating on these characteristics. Ablation characteristics were investigated through the macroscopic morphology and x-ray diffraction patterns on the surface of damaged zones, the microstructure and micro Vickers hardness on the cross-section of damaged zones, and the maximum rear-face temperature of sample sheets. It can be concluded that the ablation areas of uncoated sheet consist of the melted layer and the heat-affect layer. These ablation areas include not only the area ablated directly by the arc root, of which the depth is deeper, but also the area forming due to the splashing of molten steel, of which the depth is shallower and decreases when the area’s distance from the arc attachment point increases. For coated sheet, coating materials have decomposed and evaporated forming an ablation pit on the sheet surface, in which the steel surface is exposed, and zinc filler of coating primer has infused into the exposed surface. The ablation diameter of uncoated sheet relates to the amplitude of the 30/80 μs impulse current in quadratic function, while for coated sheet, the relation is linear. In general, under the 30/80 μs impulse current, the coating can decrease the energy injected from the arc to the steel sheet and reduce the melting and splashing of steel. As a result, the ablation severity of uncoated sheet is severer than that of coated sheet. 展开更多
关键词 arc ablation effect ANTI-CORROSION coating LIGHTNING first return stroke CURRENT 30/80 μs IMPULSE CURRENT Q235B STEEL microstructure x-ray diffraction
On Grauert–Riemenschneider Type Criteria
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作者 Zhi Wei WANG 《数学学报:英文版》 SCIE CSCD 2019年第5期609-618,共10页
Let (X,ω) be a compact Hermitian manifold of complex dimension n. In this article, we first survey recent progress towards Grauert-Riemenschneider type criteria. Secondly, we give a simplified proof of Boucksom's... Let (X,ω) be a compact Hermitian manifold of complex dimension n. In this article, we first survey recent progress towards Grauert-Riemenschneider type criteria. Secondly, we give a simplified proof of Boucksom's conjecture given by the author under the assumption that the Hermitian metric ω satisfies ■■ω^l=for all l, i.e., if T is a closed positive current on X such that ∫X Tcn/^n>0, then the class {T} is big and X is K?hler. Finally, as an easy observation, we point out that Nguyen's result can be generalized as follows:if ■■ω=0, and T is a closed positive current with analytic singularities, such that ∫X Tcn/^n>0, then the class {T} is big and X is Kahler. 展开更多
关键词 CLOSED POSITIVE CURRENT Demailly-Paun's CONJECTURE Boucksom's CONJECTURE KAHLER CURRENT Fujiki class
Electrical Brain Stimulation to Treat Neurological Disorder 预览
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作者 Bahman Zohuri David R.Modisette 《健康科学:英文版》 2019年第2期123-128,共6页
Neurological disorders with symptoms such as chronic pain,depression,and insomnia are widespread.Very weak electric fields applied through the skull can enhance or diminish neural activity and modulate brain waves in ... Neurological disorders with symptoms such as chronic pain,depression,and insomnia are widespread.Very weak electric fields applied through the skull can enhance or diminish neural activity and modulate brain waves in order to treat many of these common medical problems.This approach is to be contrasted with well-established pharmacological methods or more recent invasive electrical Deep Brain Stimulation(DBS)techniques that require surgery to insert electrodes deep into the brain.We claim that Non-Invasive Brain Stimulation(NIBS)will provide new treatment methods with much greater simplicity,lower cost,improved safety and in some cases,possibly greater effectiveness.This emerging use of NIBS is a branch of a new multidisciplinary field that we coined Neuro-systems Engineering[1].This field involves neuroscientists,psychologists,and electrical engineers.This emerging field relies on existing standards for the safe implementation of these novel treatment modalities[2].Methods of stimulating the brain are based on emerging electro-technologies such as transcranial Direct Current/Alternating Current(DC/AC)electric fields and pulsed magnetic fields.Application of functional and time-dependent brain imaging methods can be used to locate relevant brain regions and determine the most appropriate stimulation method.Application of tailored and individualized control can be combined with other therapy methods to effectively treat neurological disorders while minimizing or even eliminating the use of pharmaceuticals.In this paper,we are presenting our embodiment for a closed loop,feedback controlled,non-invasive application of electrical stimulation of the brain to enhance individual/group performance or to treat neurological disorders. 展开更多
关键词 REPETITIVE TRANSCRANIAL Magnetic Stimulation(rTMS) REPETITIVE TRANSCRANIAL Electric Stimulation(rTES) Deep Brain Stimulation(DBS) Electroencephalogram(EEG) Magnetoencephalography(MEG) TRANSCRANIAL Direct CURRENT Stimulation(tDCS) TRANSCRANIAL Alternating CURRENT Stimulation(tACS)
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Current diffusion and efficiency droop in vertical light emitting diodes
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作者 万荣桥 李滔 +6 位作者 刘志强 伊晓燕 王军喜 李军辉 朱文辉 李晋闽 汪炼成 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期561-569,共9页
Current diffusion is an old issue, nevertheless, the relationship between the current diffusion and the efficiency of light emitting diodes(LEDs) needs to be further quantitatively clarified. By incorporating current ... Current diffusion is an old issue, nevertheless, the relationship between the current diffusion and the efficiency of light emitting diodes(LEDs) needs to be further quantitatively clarified. By incorporating current crowding effect(CCE) into the conventional ABC model, we have theoretically and directly correlated the current diffusion and the internal quantum efficiency(IQE), light extraction efficiency(LEE), and external quantum efficiency(EQE) droop of the lateral LEDs.However, questions still exist for the vertical LEDs(V-LEDs). Here firstly the current diffusion length L_s(I) and L_s(II) have been clarified. Based on this, the influence of CCE on the EQE, IQE, and LEE of V-LEDs were investigated. Specifically to our V-LEDs with moderate series resistivity, L_s(III) was developed by combining L_s(I) and L_s(II), and the CCE effect on the performance of V-LEDs was investigated. The wall-plug efficiency(WPE) of V-LEDs ware investigated finally. Our works provide a deep understanding of the current diffusion status and the correlated efficiency droop in V-LEDs, thus would benefit the V-LEDs’ chip design and further efficiency improvement. 展开更多
关键词 efficiency droop VERTICAL light EMITTING diodes CURRENT CROWDING effect CURRENT BLOCKING layer
Direct Microwave Synthesis of 11-Type Fe(Te,Se)Polycrystalline Superconductors with Enhanced Critical Current Density
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作者 潘伯津 赵康 +4 位作者 刘通 阮彬彬 张帅 陈根富 任治安 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第1期56-59,共4页
We report a direct microwave synthesis method for the preparation of 11-type high quality Fe(Te,Se)polycrys- talline superconductors.The bulk samples are rapidly synthesized under the microwave irradiation during seve... We report a direct microwave synthesis method for the preparation of 11-type high quality Fe(Te,Se)polycrys- talline superconductors.The bulk samples are rapidly synthesized under the microwave irradiation during several minutes,with a subsequent annealing process at 400℃.The samples exhibit a nearly single phase of the tetragonal PbO-type crystal structure with minor impurities.Morphology characterization shows high density,tight grain connectivity and large grain sizes around 100μm with small cavities inside the sample.Resistivity and magnetization measurements both show similar superconducting transitions above 14 K.The magnetic hystere- sis measurements display broad and symmetric loops without magnetic background,and a high critical current density Jc about 1.2 ×10^4 A/cm^2 at 2K and 7T is estimated by the Bean model.Compared with the solid- state reaction synthesized samples,these superconducting bulks from microwave-assisted synthesis are possibly free of the interstitial Fe due to smaller c-axis,higher Tc in magnetic transitions,better M-H loops without magnetic background and greatly enhanced Jc,and are promising as raw materials for the non-toxic Fe-based superconducting wires for large currents and high field applications. 展开更多
关键词 MICROWAVE Synthesis POLYCRYSTALLINE SUPERCONDUCTORS ENHANCED CRITICAL Current Density
Seasonal variability of tides in the deep northern South China Sea
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作者 Jiuqiang ZHAO Yanwei ZHANG +2 位作者 Zhifei LIU Yulong ZHAO Meng WANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第4期671-683,共13页
Tides are the major energy source for ocean mixing, regulating the variation of oceanic circulation and sediment transport in the deep sea. Here twenty months of high-resolution current profiles, which were observed v... Tides are the major energy source for ocean mixing, regulating the variation of oceanic circulation and sediment transport in the deep sea. Here twenty months of high-resolution current profiles, which were observed via a mooring system at a water depth of 2100 m in the northern South China Sea(SCS), are used to investigate seasonal variability in deep-sea tides.Spectral analysis shows that tides in this region are dominated by diurnal tide, and both diurnal and semidiurnal tide are vertical mode-1 dominant. Baroclinic diurnal tidal current exhibits pronounced seasonal variability, showing its kinetic energy was the strongest in summer, and the maximum depth-averaged value was up to 86.7 cm^2 s^-2, which was about 1.5 times of that in winter and twice that in spring and autumn. In contrast, baroclinic semidiurnal tide displays no evident seasonal variability. Such seasonal variability in baroclinic tide was mainly modulated by the barotropic forcing from the Luzon Strait. On the other hand,two anticyclonic eddies and one cyclonic eddy, which originated off southwestern Taiwan in winter, crossed the mooring system.The cyclonic eddy had weak impact on current velocity in the deep sea, but the two deep-reaching anticyclonic eddies enhanced the current velocity through the full-water column by inducing strong subinertial flows. Consequently, the kinetic energy of tides was strengthened and the incoherent variance of baroclinic diurnal tide increased in winter, which contributed ~85% of the variability in diurnal tide. Meanwhile, the velocity of baroclinic diurnal tide was reduced in winter, which was attributed to the weakened stratification induced by the passage of anticyclonic eddies in the deep sea. The seasonal variability of tides in the deep northern SCS can provide a dynamic mechanism for interpreting sediment transport processes in the deep sea on different time scales. 展开更多
关键词 TIDES SEASONAL variability Subinertial current MESOSCALE EDDY DEEP northern South China Sea
原油转驳船海上作业定位能力需求分析 预览
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作者 胡开业 丁勇 +2 位作者 王宏伟 熊大鹏 杨笛 《船舶与海洋工程学报:英文版》 CSCD 2019年第2期205-212,共8页
In response to the development of deep-sea oil and gas resources,which require a high degree of cooperation by crude oil transportation equipment,a new type of ship known as the cargo transfer vessel(CTV)has been deve... In response to the development of deep-sea oil and gas resources,which require a high degree of cooperation by crude oil transportation equipment,a new type of ship known as the cargo transfer vessel(CTV)has been developed.To provide a theoretical reference for the design and equipment of the CTV’s dynamic positioning system,in this paper,we take the new deepwater CTVas the study object and theoretically and numerically analyze its operation,wind load,current load,wave load,and navigational resistance in a range of Brazilian sea conditions with respect to its positioning and towing modes.We confirm that our proposed method can successfully calculate the total environmental load of the CTVand that the CTV is able to operate normally under the designed sea conditions. 展开更多
关键词 CARGO TRANSFER VESSEL Wind LOAD Current LOAD Wave LOAD DP CAPABILITY Oil TRANSFER operation
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Experimental investigations of enhanced glow based on a pulsed hollow-cathode discharge
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作者 梁春霞 王宁 +2 位作者 段正超 何锋 欧阳吉庭 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第2期47-51,共5页
In this work, the pulsed hollow cathode discharges at low pressure argon with an axial magnetic field were studied. The results indicate that the pulsed discharge is operated in an enhanced glow(EG) mode. Under the sa... In this work, the pulsed hollow cathode discharges at low pressure argon with an axial magnetic field were studied. The results indicate that the pulsed discharge is operated in an enhanced glow(EG) mode. Under the same conditions, the discharge current of the pulsed discharge is two or three orders higher than that of the direct current discharge. The spatial and temporal evolution of the light emission shows that, the current fluctuation at the rising edge of the pulse plays an important role for the EG discharge of pulsed hollow cathode, which forms a high-density, highcurrent and long-distance plasma column outside the cavity. 展开更多
关键词 HOLLOW cathode discharge ENHANCED GLOW current FLUCTUATION ABNORMAL GLOW
Current therapies and novel approaches for biliary diseases 预览
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作者 Indu G Rajapaksha Peter W Angus Chandana B Herath 《世界胃肠病理生理学杂志:英文版(电子版)》 2019年第1期1-10,共10页
Chronic liver diseases that inevitably lead to hepatic fibrosis, cirrhosis and/or hepatocellular carcinoma have become a major cause of illness and death worldwide. Among them, cholangiopathies or cholestatic liver di... Chronic liver diseases that inevitably lead to hepatic fibrosis, cirrhosis and/or hepatocellular carcinoma have become a major cause of illness and death worldwide. Among them, cholangiopathies or cholestatic liver diseases comprise a large group of conditions in which injury is primarily focused on the biliary system. These include congenital diseases (such as biliary atresia and cystic fibrosis), acquired diseases (such as primary sclerosing cholangitis and primary biliary cirrhosis), and those that arise from secondary damage to the biliary tree from obstruction, cholangitis or ischaemia. These conditions are associated with a specific pattern of chronic liver injury centered on damaged bile ducts that drive the development of peribiliary fibrosis and, ultimately, biliary cirrhosis and liver failure. For most, there is no established medical therapy and, hence, these diseases remain one of the most important indications for liver transplantation. As a result, there is a major need to develop new therapies that can prevent the development of chronic biliary injury and fibrosis. This mini-review briefly discusses the pathophysiology of liver fibrosis and its progression to cirrhosis. We make a special emphasis on biliary fibrosis and current therapeutic options, such as angiotensin converting enzyme-2 (known as ACE2) over-expression in the diseased liver as a novel potential therapy to treat this condition. 展开更多
关键词 Chronic liver disease BILIARY FIBROSIS CURRENT THERAPIES for BILIARY FIBROSIS ANGIOTENSIN CONVERTING enzyme-2 Gene therapy
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Talking about the Influence of Human Resource Management on Enterprise Development under the New Situation 预览
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作者 Zuoming Jiang Daisheng Li Yongqi Zhou 《人力资源管理和服务》 2019年第1期8-15,共8页
With the advent of knowledge economy, international competition is becoming increasingly fierce, human resources management in the role of enterprise management is growing. In the 21st century, the trend of globalizat... With the advent of knowledge economy, international competition is becoming increasingly fierce, human resources management in the role of enterprise management is growing. In the 21st century, the trend of globalization of the world economy has been strengthened, and the development of science and technology has been changing with each passing day. The essence of comprehensive national competition is becoming the competition of human resources. Similarly, enterprises in order to compete in the fierce and healthy development, we must reduce costs and improve management efficiency, must have a set of their own talent management methods. Human resources are the most important resources in all resources, effectively play the important role of human resources in the core competitiveness, and formulate the countermeasures of human resource competition, which is of great significance to improve the core competitiveness of enterprises. In the new century to further improve the management of human resources in state-owned enterprises, improve China's enterprise human resources management system is to enliven the state-owned enterprises, improve our comprehensive national strength of the top priority, to promote China's economic development is of great significance. 展开更多
关键词 STATE-OWNED ENTERPRISE Human RESOURCE Management Current SITUATION HUMANISTIC Performance Evaluation
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水流作用下的渔网水动力数值方法研究 预览
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作者 胡克 耿宝磊 +1 位作者 赵旭 沈文君 《水道港口》 2019年第2期199-205,共7页
为了研究渔网在水流作用下的受力及变形情况,文章基于ABAQUS二次开发技术,结合网平面经验公式,编写了水动力计算模型。根据网衣的密实度、雷诺数和网平面与流速的夹角与水动力系数的关系式,计算出每个网目的水动力系数,再施加在网衣的... 为了研究渔网在水流作用下的受力及变形情况,文章基于ABAQUS二次开发技术,结合网平面经验公式,编写了水动力计算模型。根据网衣的密实度、雷诺数和网平面与流速的夹角与水动力系数的关系式,计算出每个网目的水动力系数,再施加在网衣的每个网目上,最终计算出整个网衣的水动力和变形情况。同时在该方法中也考虑了流速衰减的问题。通过此方法验证了网箱在不同网格数和沉子质量时水动力和网箱体积计算结果的准确性,未来可以应用该方法计算网箱在水流下的水动力。 展开更多
关键词 重力式网箱 水动力载荷 水流 有限元方法 ABAQUS二次开发
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Effect of inhomogeneous broadening on threshold current of GaN-based green laser diodes 预览
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作者 Yipeng Liang Jianping Liu +7 位作者 Masao Ikeda Aiqin Tian Renlin Zhou Shuming Zhang Tong Liu Deyao Li Liqun Zhang Hui Yang 《半导体学报:英文版》 EI CAS CSCD 2019年第5期67-70,共4页
The inhomogeneous broadening parameter and the internal loss of green LDs are determined by experiments and theoretical fitting. It is found that the inhomogeneous broadening plays an important role on the threshold c... The inhomogeneous broadening parameter and the internal loss of green LDs are determined by experiments and theoretical fitting. It is found that the inhomogeneous broadening plays an important role on the threshold current density of green LDs. The green LD with large inhomogeneous broadening even cannot lase. Therefore, reducing inhomogeneous broadening is a key issue to improve the performance of green LDs. 展开更多
关键词 GaN green laser diode INHOMOGENEOUS BROADENING THRESHOLD current density
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Using the Power of Images to Speak for the Earth 预览
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作者 Xin Yuan 《中外文化交流:英文版》 2019年第5期33-37,共5页
The exhibition brings pictures, video, online sharing and ocean talks from expedition masters to show the beauty of polar regions, raising the awareness of the visitors regarding the current situation of the polar reg... The exhibition brings pictures, video, online sharing and ocean talks from expedition masters to show the beauty of polar regions, raising the awareness of the visitors regarding the current situation of the polar regions and the oceans through a range of diversified programs, so as to use the power of images to speak for the earth. 展开更多
关键词 IMAGES the EARTH CURRENT SITUATION
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Ring current proton scattering by low-frequency magnetosonic waves 预览
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作者 Jiang Yu Jing Wang Jun Cui 《地球与行星物理:英文版》 CSCD 2019年第4期365-372,共8页
Magnetosonic (MS) waves are believed to have the ability to affect the dynamics of ring current protons both inside and outside the plasmasphere. However, previous studies have focused primarily on the effect of high-... Magnetosonic (MS) waves are believed to have the ability to affect the dynamics of ring current protons both inside and outside the plasmasphere. However, previous studies have focused primarily on the effect of high-frequency MS waves (f > 20 Hz) on ring current protons. In this study, we investigate interactions between ring current protons and low-frequency MS waves (< 20 Hz) inside the plasmasphere. We find that low-frequency MS waves can effectively accelerate < 20 keV ring current protons on time scales from several hours to a day, and their scattering efficiency is comparable to that due to high-frequency MS waves (>20 Hz), from which we infer that omitting the effect of low-frequency MS waves will considerably underestimate proton depletion at middle pitch angles and proton enhancement at large pitch angles. Therefore, ring current proton modeling should take into account the effects of both low- and highfrequency MS waves. 展开更多
关键词 magnetosonic WAVES ring current PROTONS wave-particle INTERACTIONS PROTON distribution EVOLUTIONS
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