Analysis on characteristics of extreme precipitation indices and atmospheric circulation in Northern Shanxi

This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average reanalysis data.The study employs techniques such as empirical orthogonal function(EOF)decomposition,MannKendall mutation and other methods to investigate the spatiotemporal distribution of extreme precipitation index in northern Shanxi and their correlation with atmospheric circulation.The research results show that:the absolute index,relative index,intensity index and sustained dry period index(CDD)in the continuous index appear from southwest to northeast.The spatial distribution characteristics of the central region decrease,while the continuous wet period(CWD)decreases from the central to the east and west.The three indices Rx1day,Rx5day,and CWD mutated in 1978,1975,and 1983 respectively,and other extreme precipitation indices all appeared in a sudden change from a low-value period to a high-value period occurred around 2010.In the high-value years of the summer extreme precipitation index,there is a significant negative anomaly in the height field in the mid-high latitude regions of Eurasia.Northern Shanxi is controlled by a broad low-pressure trough in the Lake Baikal area.Water vapor transported via the east,west,and south routes converges in the northern Shanxi region and encounters cold air from the north.There is a strong upward motion anomaly at 500 hPa in the troposphere,and the dynamic conditions of upper-level divergence and lower-level convergence lead to more summer extreme precipitation in the northern Shanxi region.Conversely,in the low-value years of the summer extreme precipitation index,northern Shanxi is affected by a strong high-pressure ridge north of Lake Baikal.There is a downward motion anomaly at 500 hPa,and the northern Shanxi region lacks water vapor.The cold and warm air cannot converge,and both the water vapor conditions and dynamic conditions are poor,which is not conducive to the production of extreme precipitation in northern Shanxi.

DISTRIBUTIONS OF CHEMICAL ELEMENTS WITH RELATION TO MAJOR WATER CIRCULATIONS IN THE CENTRAL AND NORTHERN PARTS OF THE TAIWAN STRAIT

Data obtained from a comprehensive multidisciplinary oceanographic survey in the central and northern parts of the Taiwan Strait, 24°20′-26°00′N, 118°45°-121°00′E by the Fujian Institute of Oceanology during the period May, 1983 through May, 1984, showed that the distributions of dissolved oxygen (DO), nitrate, dissolved inorganic phosphate and silicate concentrations here had obvious areal and seasonal characteristics that were mainly influenced by the seasonal circulation ofthree major water systems in the Taiwan Strait-- the Taiwan Strait Warm Water (TSWW), theZhejiang-Fujian Coastal Water (ZFCW), and the Northeastern Strait Warm Water (NESWW).

Analysis of Temporal and Spatial Distribution and Large-Scale Circulation Features of Extreme Weather Events in Shanxi Province, China in Recent 30 Years

Extreme weather events such as persistent high temperatures, heavy rains or sudden cold waves in Shanxi Province in China have brought great losses and disasters to people’s production and life. It is of great practical significance to study the temporal and spatial distribution characteristics of extreme weather events and the circulation background field. We selected daily high temperature data (≥35°C), daily minimum temperature data and daily precipitation data (≥50 mm) from 109 meteorological stations in Shanxi Province, China from 1981 to 2010, then set the period in which the temperature is ≥35°C for more than 3 days as a high temperature extreme weather event, define the station in which 24 hour cumulative precipitation is ≥50 mm precipitation on a certain day (20 - 20 hours, Beijing time) as a rainstorm weather, and determine the cold air activity with daily minimum temperature dropped by more than 8°C for 24 hours, or decreased by 10°C for 48 h, and a daily minimum temperature of ≤4°C as a cold weather process. We statistically analyze the temporal and spatial characteristics and trends of high temperature, heavy rain and cold weather and the circulation background field. We count the number of extreme weather events such as persistent high temperatures, heavy rains and cold weather frosts in Shanxi, and analyze the temporal and spatial distribution characteristics, trends and general circulation background of extreme weather events. We analyze and find out the common features of the large-scale circulation background field in various extreme weather events. Through the study of the temporal and spatial distribution characteristics of extreme weather events in Shanxi, including persistent high temperature, heavy rain or sudden cold wave frost weather, we summarize the large-scale circulation characteristics of such extreme weather events. It will provide some reference for future related weather forecasting.

The Role of Land–sea Distribution and Orography in the Asian Monsoon. Part I: Land–sea Distribution

A number of AGCM simulations were performed by including various land–sea distributions （LSDs）, such as meridional LSDs, zonal LSDs, tropical large-scale LSDs, and subcontinental-scale LSDs, to identify their effects on the Asian monsoon. In seven meridional LSD experiments with the continent/ocean located to the north/south of a certain latitude, the LSDs remain identical except the southern coastline is varied from 40 ° to 4 ° N in intervals of 5.6° . In the experiments with the coastline located to the north of 21° N, no monsoon can be found in the subtropical zone. In contrast, a summer monsoon is simulated when the continent extends to the south of 21 ° N. Meanwhile, the earlier onset and stronger intensity of the tropical summer monsoon are simulated with the southward extension of the tropical continent. The effects of zonal LSDs were investigated by including the Pacific and Atlantic Ocean into the model based on the meridional LSD run with the coastline located at 21 °N. The results indicate that the presence of a mid-latitude zonal LSD induces a strong zonal pressure gradient between the continent and ocean, which in turn results in the formation of an East Asian subtropical monsoon. The comparison of simulations with and without the Indian Peninsula and Indo-China Peninsula reveals that the presence of two peninsulas remarkably strengthens the southwesterly winds over South Asia due to the tropical asymmetric heating between the tropical land and sea. The tropical zonal LSD plays a crucial role in the formation of cumulus convection.

Effects of particle type on the particle fluidization and distribution in a liquid–solid circulating fluidized bed boiler

A liquid-solid circulating fluidized bed boiler is designed and built for visualization research by applying the fluidized bed heat transfer and fouling prevention technology to the water side of the boiler. Four types of engineering plastic particles with different physical properties are selected as the solid working media. The effect of particle types on the fluidization and distribution of particles in the boiler is investigated under different feedwater flow rates and amount of added particles by using the charge couple device image measurement and acquisition system. The results show that all kinds of particles can't be normally fluidized and accumulate in the drum at low amount of added particles and feedwater flow rate. The particles with great density and low sphericity are more likely to accumulate. The average solid holdup in the riser tubes increases with the increase in feedwater flow rate and the amount of added particles. The non-uniform degree of particle distribution in the riser tubes generally decreases with the increase in feedwater flow rate and the amount of added particles. The particles with small density and settling velocity have high average solid holdup in the riser tubes under close sphericity. In generally,the smaller the density and settling velocity, the more uniform the particle distribution in the riser tubes.Three-dimensional diagrams of the non-uniform degree of particle distribution in the riser tubes of the boiler are established.

Determination of the Circulation for a Large-Scale Wind Turbine Blade Using Computational Fluid Dynamics

The determination of the circulation for wind turbine blades is an important problem in engineering.In the present study,we develop a specific approach to evaluate the integral that represents mathematically the circulation.First the potentialities of the method are assessed using a two-dimensional NACA64_A17 airfoil as a testbed and evaluating the influence of different integration paths and angles of attack on the circulation value.Then the method is applied to blades with different relative heights in order to provide useful reference data to be used for the optimization and reverse design of wind turbine blades.As shown by the results,the integral value changes with the integral path,and an“optimal circle radius”exists.We calibrate the integral value by comparing its value with the lift formula.In this was we succeed in showing that there is a certain error when the radius is too small.However,the error can increase rapidly when the radius is too large.When the radius of the circle is 1–6 times the chord length,the error of all integral values is less than 5%.The optimal radius varies with the angle of attack.

Analysis on the Gale Climate Characteristics and Circulation Situation in Jinzhou Area

Based on the gale observation data in 5 observation stations in Jinzhou area from 1973 to 2007,the gale trend and the periodic change in Jinzhou area were analyzed by using the linear trend estimation method and the spectral analysis method. Meanwhile,the circulation situation characteristics and the spatial-temporal distribution characteristics of gale in four seasons were discussed by surveying generally the weather charts. The results showed that the gale in Jinzhou area presented the fluctuation decline trend and had 3.5,7.0 years periodic changes. The gale in spring is the most and in summer was the least. It was less in winter and autumn. Seen from the analysis on the circulation situation,the gale circulation situation in Jinzhou area was similar to in Liaoning. The circulation situation in spring was basically consistent with in autumn,winter. The main situations had 3 kinds:north high south low(west high east low) ,two high clipping low,south high north low(east high west low) . In summer,the regional gale weather was mainly caused by the meso-micro scale system.

Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation

The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)method.The details of the gas-solid flow behaviors of PCFB are revealed.Based on the gas-solid flow pattern,the particles tend to move more orderly under elevated pressures.With an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient increases.With an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence time.The back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient.

Calculation of flow distribution in air reverse circulation bit interior fluid field by simplifying air flow model

By simplifying the characters in the air reverse circulation bit interior fluid field, the authors used air dynamics and fluid mechanics to calculate the air distribution in the bit and obtained an equation of flow distribution with a unique resolution. This study will provide help for making certain the bit parameters of the bit structure effectively and study the air reverse circulation bit interior fluid field character deeply.

Validation of actuator disc circulation distribution for unsteady virtual blades model

The actuator disc method is an engineering approach to reduce computer resources in computational fluid dynamics(CFD)simulations of helicopter rotors or aeroplane propellers.Implementation of an actuator disc based on rotor circulation distribution allows for approximations to be made while reproducing the blade tip vortices.Radial circulation distributions can be formulated according to the nonuniform Heyson-Katzoff“typical load”in hover.In forward flight,the nonuniform disk models include“azimuthal”sin and cos terms to reproduce the blade cyclic motion.The azimuthal circulation distribution for a forward flight mode corresponds to trimmed conditions for the disk rolling and pitching moments.The amplitude of the cos harmonic is analysed and compared here with presented in references data and CFD simulations results.

Analysis on the rules of prescriptions for ischemic stroke based on the traditional Chinese medicine inheritance auxiliary system

In China,traditional Chinese medicine is widely used in the treatment of ischemic stroke,but its prescription rules needs to be further studied.This paper uses the traditional Chinese medicine inheritance auxiliary system(a software)to analyze the composition rules of a large number of prescriptions for the treatment of ischemic stroke,and discusses the clinical rationality of the new prescriptions.We found that the prescriptions for the treatment of ischemic stroke are mainly composed by herbs for promoting blood circulation and removing blood stasis,dredging collaterals and tonifying deficiency,and some of the new prescriptions are also in line with this characteristic.This paper can provide reference for clinical prescription in the treatment of ischemic stroke and the development of related new drugs.

Process Design of Cryogenic Distribution System for CFETR CS Model Coil

The superconducting magnet of Central Solenoid（CS） model coil of China Fusion Engineering Test Reactor（CFETR） is made of Nb_3Sn/Nb Ti cable-in-conduit conductor（CICC）,and operated by forced-flow cooling with a large amount of supercritical helium.The cryogenic circulation pump is analyzed and considered to be effective in achieving the supercritical helium（SHe） circulation for the forced-flow cooled（FFC） CICC magnet.A distributed system will be constructed for cooling the CFETR CS model coil.This paper presents the design of FFC process for the CFETR CS model coil.The equipment configuration,quench protection in the magnet and the process control are presented.

Relationship between Tissue Distributions of Modified Wuzi Yanzong Prescription(加味五子衍宗方) in Rats and Meridian Tropism Theory

Objective： To investigate the relationship between tissue distributions of modified Wuzi Yanzong prescription（加味五子衍宗方, MWP） in rats and meridian tropism theory. Methods： A high-performance liquid chromatography with Fourier transform-mass spectrometry（HPLC-FT） method was used to identify the metabolites of MWP in different tissues of rats after continued oral administration of MWP for 7 days. The relationship between MWP and meridian tropism theory was studied according to the tissue distributions of the metabolites of MWP in rats and the relevant literature. Results： Nineteen metabolites, mainly flavanoid compounds, were detected in the different rat tissues and classified to each herb in MWP. Further, it was able to establish that the tissue distributions of the metabolites of MWP were consistent with the descriptions of meridian tropism of MWP available in literature, this result might be useful in clarifying the mechanism of MWP on meridian tropism. In the long run, these data might provide scientific evidence of the meridian tropism theory to further promote the reasonable, effective utilization, and modernization of Chinese medicine. Conclusion： The tissue distributions of MWP in vivo were consistent with the descriptions of meridian tropism of MWP.

益肾壮骨活血方联合针刀疗法治疗髌骨骨性关节炎临床观察

目的探讨髌骨骨性关节炎患者采用益肾壮骨活血方联合针刀疗法的临床效果。方法从南昌市洪都中医院2021年6月—2022年6月收治的髌骨骨性关节炎患者中抽取70例作为研究对象,使用随机数字表法将其分为对照组和观察组,每组35例。对照组和观察组的治疗方法分别为常规西医治疗、益肾壮骨活血方联合针刀治疗,对比两组治疗前后的炎性因子水平和西安大略和麦克马斯特大学骨关节炎指数(WOMAC)评分。结果治疗后,观察组的白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)水平均较对照组低(P<0.05),WOMAC评分较对照组低(P<0.05)。结论髌骨骨性关节炎患者采用益肾壮骨活血方与针刀联合治疗效果较显著,不仅能有效减轻炎症反应,还能改善关节功能,临床可进一步推广。

Input function and simulated distributions of tritium in the North Pacific

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 30°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

MM5 Simulations of the China Regional Climate During the LGM.Ⅱ:Influence of Change of Land Area,Vegetation,and Large-scale Circulation Background

Using a regional climate model MM5 nested to an atmospheric global climate model CCM3, a series of simulations and sensitivity experiments have been performed to investigate the relative LGM climate response to changes of land-sea distribution, vegetation, and large-scale circulation background over China. Model results show that compared with the present climate, the fluctuations of sea-land distribution in eastern Asia during the LGM result in the temperature decrease in winter and increase in summer. It has significant impact on the temperature and precipitation in the east coastal region of China. The impact on precipitation in the east coastal region of China is the most significant one, with 25%-50% decrease in the total precipitation change during the LGM. On the other hand, the changes in sea-land distribution have less influence on the climate of inland and western part of China. During the LGM, significant changes in vegetation result in temperature alternating with winter increase and summer decrease, but differences in the annual mean temperature are minor. During the LGM, the global climate, i.e., the large-scale circulation background has changed significantly. These changes have significant influences on temperature and precipitation over China. They result in considerable temperature decreases in this area, and direct the primary patterns and characteristics of temperature changes. Results display that, northeastern China has the greatest temperature decrease, and the temperature decrease in the Tibetan Plateau is larger than in the eastern part of China located at the same latitude. Moreover, the change of large-scale circulation background also controls the pattern of precipitation change. Results also show that, most of the changes in precipitation over western and northeastern parts of China are the consequences of changing large-scale circulation background, of which 50%-75% of precipitation changes over northern and eastern China are the results of changes in large-scale circulation background. Over China, the LGM climate responses to different mechanisms in order of strength from strong to weak are, the large-scale circulation pattern, sea- land distribution, vegetation, CO2 concentration, and earth orbital parameters.

The comparison of statistical features and synoptic circulations between the eastward-propagating and quasi-stationary MCSs during the warm season around the second-step terrain along the middle reaches of the Yangtze River

Mesoscale convective systems(MCSs) around the second-step terrain(106°–113°E, 28°–35°N), along the middle reaches of the Yangtze River, were detected, tracked and classified using a black body temperature(TBB) dataset during May to August 2000–2016(except 2005). The MCSs were divided into eastward-propagating(EP) and quasi-stationary(QS) types, to compare their spatial and temporal distributions and convective intensities, and to identify the favorable synoptic conditions for the formation and evolution of EP MCSs. The results showed that both MCS types occurred most often in July. The EP MCSs were mainly initiated over the eastern regions of the study area, while the QS type mainly originated in the western regions of the study area. Both MCS types mainly formed in the afternoon, but a second peak occurred in the early morning for QS MCSs. The EP MCSs had a larger cloud area at their mature stage and a lower cloud brightness temperature, indicating more intense convection. Additionally, the longer lifetime and further eastward propagation of the EP MCSs meant that they had a great influence on the precipitation over the middle and lower reaches of the Yangtze River. Synoptic circulation analysis demonstrated that the combination of the mid-level low trough east of the Tibetan Plateau(TP), and the western pacific subtropical high(WPSH), favored the formation and eastward propagation of EP MCSs. The positive vertical relative vorticity and stronger vertical wind shear provided dynamic conditions favorable for convective organization and development. Furthermore, a stronger low level jet imported warm and moist air to the eastern edge of, and the regions east of, the second-step terrain. The substantial convergence of water vapor promoted the development and long-lived maintenance of the EP MCSs.

门诊共济保障方式改革、零售药店发展与处方流转

职工医保门诊共济保障改革是完善基本医保制度的重大举措。本次改革将符合条件的定点零售药店纳入门诊统筹报销,为零售药店的高质量发展带来重大机遇。门诊共济保障改革以及零售药店实现高质量发展的关键环节是医院处方的流转。本文认为,处方流转的主要障碍一是处方管理及药品使用安全管理上的部门分割以及由此带来的风险责任冲突及利益冲突,二是零售药店本身的经营与管理模式还难以适应处方的风险管理要求。实现处方的畅通流转一是要坚持“三医”协同治理,建立处方管理及药品使用安全管理全链条监管机制,打破部门分割,充分尊重参与各方的管理要求及利益诉求;二是零售药店要转变运营模式,提升药事服务和商业服务能力,适应门诊共济保障改革后处方流转的要求。

单芯海缆两端环流不匹配问题及评价方法研究

海缆是海上风电系统重要构成部分,接地环流是制约海缆设计及运行状态的关键要素。实际运行经验表明部分海上风场的单芯海缆存在陆上段和海上段接地环流严重不匹配现象,但是造成这种不匹配工况的原因不明,更无法根据这一现象对海缆运行状态进行清晰判断。该文依据现场海缆实际结构建立其分布参数模型,针对铠装接地和铠装金属护套全线接地两种接地方式对海缆接地环流进行分析,指出铠装全线接地时出现不匹配接地环流的原因为铠装和金属护套之间存在短路电阻;而铠装和金属护套全线接地情况下,出现不匹配接地环流的原因为铠装和金属护套之间存在短路电阻或者海缆两端接地电阻不匹配。在此基础上,提出基于环流的海缆运行情况评价方法,为实际海缆运行状态的判断提供参考依据。