基于回归分析的刮板取料机俯仰拉力曲线拟合研究

文中针对刮板式取料机中俯仰机构钢丝绳拉力安全值确定简单、无法全面、准确评估刮板取料设备运行安全系数的问题,对常用俯仰角度以及其对应的拉力值进行回归分析,计算俯仰角度及各角度对应拉力的曲线回归方程,并检测该曲线的拟合程度和显著性。以该方程为约束建立钢丝绳俯仰拉力保护的数学模型,通过将空载状态下或重载状态下取料机的钢丝绳理论拉力保护曲线设置为安全检测程序,结合控制软件的运行逻辑对设备的启动、下俯、行车进行限制,确保该设备运行的安全性。

基于改进深度强化学习的边缘计算服务卸载算法

在边缘计算(EC)网络中,针对边缘节点计算资源和存储空间有限的问题,提出一种基于改进深度强化学习(DRL)的边缘计算服务卸载(ECSO)算法,以降低节点处理时延和提高服务性能。具体来说,将边缘节点服务卸载问题转化为资源受限的马尔可夫决策过程(MDP),利用DRL算法解决边缘节点的请求状态转移概率难以精确预测的问题;考虑到边缘节点执行缓存服务的状态动作空间过大,定义新的动作行为替代原有动作,并依据提出的动作筛选算法得到最优动作集合,以改进计算动作行为奖励值的过程,进而大幅度降低动作空间大小,提高算法训练的效率以及收益。仿真实验结果表明,对比原深度Q网络(DQN)算法、邻近策略优化(PPO)算法以及传统的最流行(MP)算法,ECSO算法的总奖励值分别提升了7.0%、12.7%和65.6%,边缘节点服务卸载时延分别降低了13.0%、18.8%和66.4%,验证了算法的有效性,说明ECSO能有效提升边缘计算服务的卸载性能。

某水电站桥式起重机变频控制系统异常停机故障的检修与处理

文章阐述了某水电站桥式起重机变频系统故障的检修与处理过程,并对检修经验进行了总结。

全球卫星导航系统的现状与进展

为了进一步研究全球卫星导航系统,较全面地概述GPS、GLONASS、BDS和Galileo的发展历程和技术现状,并对四大系统技术进行比较分析。结果表明:全球卫星导航系统朝着兼容统一共享的方向发展;且通过高精度定位比较分析,说明GPS和BDS定位精度趋向相同。

基于电池内阻的局部一致性分析

为了提高现有的车用锂离子电池一致性分析效率,文章提出了一种基于电池内阻的局部一致性分析方法。首先,根据电池的特性分析,建立电池等效电路模型,采用最小二乘法对电池内阻进行辨识,实现电池参数标定;其次,将辨识结果储存,建立数据库;最后,将数据作为输入进行局部一致性分析,得出分析结果。实验结果验证了该方法的有效性。

基于MATE的电力系统分网多速率电磁暂态并行仿真方法

针对电力系统电磁暂态仿真效率低的问题,提出一种基于MATE的分网多速率电磁暂态并行仿真方法,该方法支持2种及2种以上仿真步长。提出了主同步时刻、子同步时刻和非同步时刻等概念以描述不同时刻的求解过程。在非同步时刻,通过大步长和中步长子网戴维南电势插值结果计算连接线电流,完成小步长子网的计算;在子同步时刻,利用大步长子网戴维南电势插值结果计算连接线电流,并综合考虑中步长内连接线电流的累积效应,完成中步长和小步长子网的计算;在主同步时刻,通过各子网戴维南等值计算连接线电流,并综合考虑大步长内连接线电流的累积效应,得到全网络的仿真结果。仿真算例表明,该方法可以根据所划分子网的特性选择合适的仿真步长,能在基本不损失仿真精度的前提下大大提高仿真效率,对实现大规模电力系统的实时仿真具有重要理论和实践意义。

从典型案例透视数字时代实体书店生存新法则

实体书店在如今的数字出版浪潮和用户转移与流失的夹击下,发展并不乐观。然而,有些实体书店却不仅经受住了市场考验,且发展势头越发强劲。论文选取了几个比较有代表性的实体书店作为案例,剖析这些书店的生存法则和经营之道,并从案例中提炼出这些实体书店成功的共通之处,为我国实体书店在新时代生存提供思路和决策参考。

甘肃北山铅炉子沟地区金属矿成矿规律及矿产预测

甘肃省金塔县铅炉子沟地区位于塔里木-中朝板块北缘大陆边缘区柳园-穿山驯前陆成矿带东南段,是我国北山地区著名的多金属成矿带。本文通过对区域成矿地质背景、成矿地质条件、地球物理、地球化学、遥感异常特征及成矿规律的综合研究与分析,认为该区具有寻找海相沉积-热液再造型、岩浆期后热液(脉)型、接触交代(矽卡岩)型三大类多金属矿床的有利条件,并划分出2条Ⅳ级成矿亚带、4个成矿期。综合圈定重点成矿远景区9个,A类远景区5处,B类远景区1处,C类远景区3处;优选圈定出找矿靶区10个,A类5个,B类1个,C类4个。本次研究为本区下一步开展矿产资源勘查评价和找矿靶区优选提供了科学依据,指明了地质找矿方向。

The Distribution and Variability of Simulated Chlorophyll Concentration over the Tropical Indian Ocean from Five CMIP5 Models

Performances of 5 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) in simulating the chloro-phyll concentration over the tropical Indian Ocean are evaluated. Results show that these models are able to capture the dominant spatial distribution of observed chlorophyll concentration and reproduce the maximum chlorophyll concentration over the western part of the Arabian Sea, around the tip of the Indian subcontinent, and in the southeast tropical Indian Ocean. The seasonal evolution of chlorophyll concentration over these regions is also reproduced with significant amplitude diversity among models. All of 5 mod-els is able to simulate the interannual variability of chlorophyll concentration. The maximum interannual variation occurs at the same regions where the maximum climatological chlorophyll concentration is located. Further analysis also reveals that the Indian Ocean Dipole events have great impact on chlorophyll concentration in the tropical Indian Ocean. In the general successful simulation of chlorophyll concentration, most of the CMIP5 models present higher than normal chlorophyll concentration in the eastern equatorial Indian Ocean.

甘肃省车路沟北金矿找矿方向探讨: 来自阿尔金断裂带东段“金三角”金矿控矿因素对比研究的启迪

甘肃省玉门市车路沟北金矿地处北祁连造山带西端和阿尔金韧性剪切带东段交汇部位,是区域上著名的西北“金三角”。该矿的形成与阿尔金左行韧性剪切带关系密切并且产出受其次级分支断裂带的控制;古生界在区域上普遍含金较高,是该矿主要的矿源层;区域岩浆活动强烈,与金矿(化)体紧密伴生,车路沟花岗闪长杂岩体为该矿形成提供热源和部分矿源。结合区域成矿背景,采用区域矿床综合类比的方法,详细对比了车路沟北金矿区和寒山金矿、鹰嘴山金矿、滴水山金矿、牛毛泉东金矿、胡湾子金矿、南湖西金矿、红口子金矿、车路沟金矿以及昌马金矿等“金三角”金矿在地层-构造-岩浆岩-物化遥异常特征等控矿因素以及矿体、矿石、围岩蚀变等矿床地质特征等等方面的情况。研究结果表明:车路沟北金矿和上述诸金矿控矿因素基本类同,矿床地质特征极其相似,作为“金三角”金矿带在北东方向上的延伸,具备深部隐伏较大规模矿床的潜力。在此基础上进一步系统总结了“金三角”金矿的找矿模型,探讨了找矿标志和找矿方向。研究成果能对本矿区以及北祁连地区构造蚀变岩型金矿床进一步的勘查工作有所启迪。

Near-surface structure and energy characteristics of the Antarctic Circumpolar Current

Historical surface drifter observations collected from the Southern Ocean are used to study the near-surface structure, variability, and energy characteristics of the Antarctic Circumpolar Current （ACC）. A strong, nearly zonal ACC combined with complex fronts dominates the circulation system in the Southern Ocean. Standard variance ellipses indicate that both the Agulhas Return Current and the East Australian Warm Current are stable supplements of the near-surface ACC, and that the anticyclonic gyre formed by the Brazil warm current and the Malvinas cold current is stable throughout the year. During austral winter, the current velocity increases because of the enhanced westerly wind. Aroused by the meridional motion of the ACC, the meridional velocity shows greater instability characteristics than the zonal velocity does over the core current. Additionally, the ACC exhibits an eastward declining trend in the core current velocity from southern Africa. The characteristics of the ACC are also argued from the perspective of energy. The energy distribution suggests that the mean kinetic energy （MKE）, eddy kinetic energy （EKE）, and are strong over the core currents of the ACC. However, in contrast, EKE/MKE suggests there is much less （more） eddy dissipation in regions with strong （weak） energy distribution. Both meridional and zonal energy variations are studied to illustrate additional details of the ACC energy characteristics. Generally, all the energy forms except EKE/MKE present west-east reducing trends, which coincide with the velocity statistics. Eddy dissipation has a much greater effect on MKE in the northern part of the Southern Ocean.

甘肃白银厂及外围地区1∶5万地球化学特征及找矿远景

甘肃白银厂及外围地区是北祁连铜多金属成矿带的主要地段。通过研究1∶5万水系沉积物地球化学实测资料,阐明了该区的元素含量特征、元素离散程度、元素组合特征、单元素异常特征、组合异常特征、综合异常特征等,发现该区Au,Ag,Cu,Pb,Zn,Mn,Fe等元素具一定成矿潜力。结合野外异常查证,推断多数异常受岩浆和构造作用控制,区内与海相火山岩有关且强度较高、元素组合较好的异常区有利于成矿。据地球化学异常,结合成矿地质构造背景,进一步优选出找矿远景区9处,为该区下一步的找矿工作提供了依据和参考。

The observed tidal and residual currents in the Andaman Sea during the second half of 2016

The characteristics of currents and tidal currents in the Andaman Sea（AS） are studied during the second half of2016 using observed data from a moored acoustic Doppler current profiler（ADCP） deployed at 8.6°N, 95.6°E.During the observation period, the mean flow is 5–10 cm/s and largely southward. The root mean square and kinetic energies of the low and high frequency flows, which are divided by a cutoff period of 5 d, are at the same level, indicating their identical importance to the total current. A power spectrum analysis shows that intraseasonal oscillations, a tidal-related semilunar month signal, a semidiurnal tidal signal and periods of 3–4 d are prominent. The barocliny of an eddy kinetic energy is stronger than the mean kinetic energy, both of which are the strongest on the bottom and the weakest at 70 m depth. Residual currents are largely southward（northward） during the summer（winter） monsoon season. Two striking peaks of the southward flow cause the 80 d period of meridional currents. The first peak is part of a large-scale circulation, which enters the AS through the northern channel and exits through the southern channel, and the second peak is part of a local vortex. The 40 d oscillation of the zonal current is forced by geostrophic variations attributed to local and equatorial remote forcing. The tidal current is dominated by semidiurnal constituents, and among these, M2 and N2 are the top two largest major axes. Moreover, astronomical tidal constituents MM and MSF are also significant. Diurnal constituents are weak and shallow water tides are ignorable. The aims are to introduce the new current data observed in the AS and to provide initial insights for the tidal and residual currents in the Andaman Sea.

西秦岭温泉—中川一带金属矿床的成矿规律及找矿预测

西秦岭温泉—中川一带实施的1∶5万矿产地质调查项目,共圈定1∶5万局部高磁异常33处,1∶5万地球化学综合异常11处,发现矿点2处,矿化点5处,矿种有金、钼、铁、铜、铷等。通过分析研究区成矿地质条件、1∶5万地球物理和地球化学综合异常特征、矿(化)点特征及分布规律等,阐明了该区成矿时空分布规律和矿产共生组合规律,划分成矿远景区9处,提交找矿靶区6处。对其中2处找矿靶区进行槽探验证的结果为:关子镇幅玉杨观找矿靶区圈定了4条含铷矿化伟晶岩脉和多处铁矿化破碎蚀变带,具有形成伟晶岩型铷矿的潜力;礼县幅李坝金矿床南侧百叶沟—河西沟找矿靶区圈定了14条蚀变破碎带,在矿化蚀变带内圈定了11条金矿(化)体,具有形成构造蚀变岩(微细粒浸染状)型金矿床的潜力。

伊春森林康养项目设计初探

森林康养是康养产业和生态旅游产业相结合的复合型产业,是“十四五”规划中健康中国建设、生态文明建设、绿色发展建设以及普惠性养老服务的重点发展领域。因此森林康养的前景光明,市场发展潜力巨大,森林康养旅游产业适逢其会。通过调查,探析伊春森林康养旅游发展影响因素对康养项目设计进行探究。

甘肃白银厂及其外围地区金属矿成矿规律及矿产预测

通过甘肃省白银厂及其外围地区矿产远景调查项目,共圈定1∶5万航磁异常12个、1∶5万高磁异常7个、1∶5万化探综合异常64个,新发现矿点4处、矿化点6处,矿种有铜、铅、锌等。通过对研究区成矿地质条件、1∶5万物化探综合异常特征、矿(化)点分布特征等进行综合分析研究,阐明了该区成矿的时空分布规律和矿产的共生组合规律,总结出区内典型矿床“多位一体”找矿预测模型。综合圈定重点成矿远景区9个,其中A类远景区3处,B类远景区2处,C类远景区4处;优选圈定找矿靶区4个,其中A类1个,B类1个,C类2个。

Extreme Sea Level Rise off the Northwest Coast of the South China Sea in 2012

Tide gauge data are used to investigate sea level variability off the northwest coast of the South China Sea(SCS) in 2012,and a significant sea level elevation with a magnitude approaching 79 mm is observed.Analysis suggests that an abnormal sea surface heat flux and freshwater flux may have contributed to this abnormal rise in sea level,together with the remote influence of an ENSO event.Further investigation shows that the event was dominated by the positive freshwater flux,where large volumes of water entered the ocean,and a maximum is centered to the south of Guangdong province,China.Simultaneously,a positive anomalous heat flux occurred in the northwestern part of the SCS,which is considered to have made a positive contribution to the high local sea level elevation.In addition to the heat flux,the ENSO event also had a significant effect on the event,where the La Ni?a-induced northwest Pacific cyclone contributed to sea level rise over the northwestern SCS through dynamic and thermodynamic interactions.

Zooplankton diel vertical migration and influence of upwelling on the biomass in the Chukchi Sea during summer

The diel vertical migration （DVM） of zooplankton and the influence of upwelling on zooplankton biomass were examined using water column data of current velocity and mean volume backscattering strength （MVBS） collected by moored acoustic Doppler current profilers （ADCPs） deployed in the southeastern Chukchi Sea during the 5th Chinese National Arctic Research Expedition （CHINARE） in summer 2012, combined with the satellite observational data such as sea surface temperature （SST）, wind, and chlorophyll a （Chl a）. Hourly acoustic data were continuously collected for 49-d in the mooring site. Spectral analysis indicated that there were different migrating patterns of zooplankton, even though precisely classifying the zooplankton taxa was not available. The prevailing 24-h cycle corresponded to the normal DVM with zooplankton swimming upwards at sunrise and returning to deep waters at sunset. There was a clear DVM in the upper 17 m of the water column during the period with distinct day-night cycles, and no active DVM throughout the water column when the sun above the horizon （polar day）, suggesting that light intensity was the trigger for DVM. Also there was a second migrating pattern with 12-h cycle. The upwelling event occurring in the northwest of Alaskan coastal area had important influence on zooplankton biomass at the mooring site. During the upwelling, the SST close to the mooring site dropped significantly from maximal 6.35℃to minimal 1.31℃ within five days. Simultaneously, there was a rapid increase in the MVBS and Chl a level, suggesting the aggregation of zooplankton related to upwelling.

血液透析患者肝素诱导的血小板减少伴鼻出血一例

1病例简介患者女,16岁,因“自服敌敌畏160 m L后1 h”于2021年12月1日15:03入平邑县人民医院急诊科。患者既往体健,无血小板减少症及其他引起血小板减少的病史,否认药物、食物过敏史。查体:体温37.6℃,呼吸频率161次/min,呼吸23次/min,血压112/65 mm Hg(1mm Hg=0.133 k Pa);精神差,呼吸困难,意识不清,流延、大汗、肌肉震颤、恶心、呕吐、呕吐物为胃内容物伴刺鼻农药味,大小便失禁。

白藜芦醇通过抑制线粒体凋亡途径缓解热刺激诱导的小鼠心肌细胞凋亡

目的:探讨白藜芦醇(Res)对热刺激诱导的小鼠心肌细胞(MCM)凋亡的保护作用。方法:复制热刺激诱导MCM凋亡模型。首先采用实时无标记细胞分析技术检测Res对MCM存活率的影响;然后采用Annexin V-FITC/7-AAD双染法检测不同浓度Res给药组对MCM凋亡率的影响。JC-1探针法检测线粒体膜电位,初步确证MCM凋亡依赖于线粒体凋亡途径。利用全自动荧光酶标仪检测荧光探针(Ac-LEHD)2-R110标记的Caspase-9相对表达量;利用流式细胞仪检测荧光探针TF2-DEVD-FMK标记的Caspase-3/7的相对表达量;Western Blot法检测Bax、Bcl-2、COXⅣ蛋白的表达;ELISA方法检测细胞色素C(Cyt-C)含量、比色法测定Cyt-C氧化酶活性。结果:与模型组比较,Res高剂量及中剂量组细胞凋亡率显著降低(P<0.05,P<0.01),各组均可显著改善线粒体膜电位(P<0.01),Res高剂量及低剂量组Cyt-C释放量显著降低(P<0.05,P<0.01),Res各组均可显著降低Caspase-9活性(P<0.01),R es高剂量组可显著降低Ca s p a s e-3/7活性(P<0.01),B c l-2/B ax比值显著升高(P<0.01,P<0.05),Res干预后Cyt-C氧化酶活性均升高但差异无统计学意义。结论:Res通过抑制线粒体凋亡途径缓解热刺激诱导的MCM凋亡。