Mechanisms of support failure and prevention measures under double-layer room mining gobs——A case study: Shigetai coal mine

In the practice of mining shallow buried ultra-close seams,support failure tends to occur during the process of longwall undermining beneath two layers of room mining goaf(TLRMG).In this paper,the factors causing support failure are summarized into geology and mining technology.Combining column lithology and composite beam theory,the key stratum of the rock strata is determined.A finite element numerical simulation is used to analyze the overlying load distribution rule of the main roof for different plane positions of the upper and lower room mining pillars.The tributary area theory(TAT)is adopted to analyze the vertical load distribution of each pillar,and dynamic models of coal pillar instability and main roof fracture are established.Through key block instability analysis,two critical moments are established,of which critical moment A has the greater dynamic load strength.Great economic losses and safety hazards are created by the dynamic load of the fracturing of the main roof.To reduce these negative effects,a method of pulling out supports is developed and two alternative measures for support failure prevention are proposed:reinforcing stope supports in conjunction with reducing mining height,or drilling ground holes to pre-split the main roof.Based on a comprehensive consideration of economic factors and the two categories of support failure causes,the method of reinforcing stope supports while reducing mining height was selected for use on the mining site.

Hidden Dangers and Preventive Measures in the Inventory of Articles in Operating Room

Operating Room is an important place for surgical diagnosis and treatment and rescue of patients. With the rapid development of medical technology, high, precision, sharp continuous development, operating room safety management is particularly important. The error of the counting of the surgical articles causes the foreign body left in the patient’s body, which will cause irreversible damage to the patient and even cause the medical dispute and touch the legal problem. Operation items inventory system is an important working system in the operating room. Scientific and standardized methods and systems for counting surgical instruments and dressings during operation can prevent foreign bodies from being left in the body, prevent errors and accidents in the operating room, and are very important for ensuring the safety of the operation of patients. In order to ensure the safety of patients, it is necessary to ensure the correct inventory of surgical items. The factors affecting the accuracy of item counting in the operating room and the preventive measures are summarized as follows.

Impact factors and improvement measures of enviroment quality in cleaning operating room

Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision infection in cleaning operating room were retro-

建筑装饰板材的ISO ROOM大型热释放速率测试与研究

本文介绍ISOROOM火灾实验方法及其对建筑装饰板材的热释放速率(HRR,HeatReleaseRate)测试与研究,同时还研究了热释放速率与室内燃烧过程中其它动力学相关参数的关系。研究结果表明,三合板(PLY)、中密度纤维板(MDFB)和三聚氰胺面板(MFCB)都有具很高的热释放速率,且特征相似;而阻燃压合板(FRCB)和石膏板(GYP)的热释放速率很低,不过阻燃压合板(FRCB)在室内高温长时间作用下能发生轰燃。研究结果还表明,建筑装饰材料的ISOROOM实验的热释放速率对室内热层温度、地面热流强度和出口气体流速有显著的影响。

Ultrasound Biomicroscopic Dark Room Provocative Test

Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7

Fault Tree Analysis of Fire and Explosion Accidents for Dual Fuel （Diesel/Natural Gas） Ship Engine Rooms

In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel(diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis.The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events.According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.

The Center of Crisis Management and Situation Room

Countries have to pre-evaluate threats and risks that may incur their national security and national interests, take the necessary preventive measures timely, and pursue decisive policies within the limits of the possibilities of their national power, by keeping a close watch on ongoing and conceivable crises and new developments. Like statesmen, also the international security organizations have to foresee the coming or anticipated threats and opportunities, take the necessary precautions and when necessary even to react by using force. Starting from time of peace, all these require an effective crisis management system that would warn and manage the threats that would create such crises. There are, however, crisis management centers and situation rooms in the focal points of the physical substructure of the crisis management system. In this article, by looking at the attributions of an effective crisis management system, structure of the crisis management centers and situation rooms will be questioned at international and national levels.

基于计量测试技术的气流组织与机房空调节能运行研究

为量化气流组织对机房空调节能的影响,以某数据中心作为测试对象,基于计量测试技术将抽象的气流组织参数化、指标化,通过测量数据的分析,指出了机房内气流组织存在的问题,并制定了有针对性的气流组织调优和空调节能运行策略。测试数据表明,在机房热环境满足国家标准要求的前提下,机房空调节能率超过28%。

基于混合现实技术的船舶机舱集中操控试验装置设计与实现

文章提出一种基于混合现实(MR)的船舶机舱设备集中操控试验装置和管控方法,即时收集船舶机舱内数据,针对收集的数据建立数学模型,模拟舱内三维场景,从而对舱内设备实施控制。研究了基于MR的船舶机舱设备集中操控系统设计方案和方法,应用Faster R-CNN目标检测网络深度学习的船舶机舱设备状态指示识别框架与算法。从MR机舱设备集中操控流程、构建机舱三维模型及其优化、集中操控方法及其实操训练等环节的迭代研发,完成了MR机舱设备集中操控功能的测试验证。将混合现实技术应用于轮机设备操作、机舱资源管理等实践实训教学中,增强了船舱空间分析和可视化的交互效果。

2020年汉中市梅毒血清学检测室间质评结果分析

目的通过汉中市2020年医疗卫生机构实验室的梅毒血清学质量评价活动,了解医疗卫生机构实验室的梅毒血清学检测水平,分析影响检测能力的相关因素和存在问题。方法每家实验室发放5份梅毒血清质控品,考核内容包括梅毒特异性抗体定性试验、梅毒非特异性抗体定性和定量试验共3种检测项目。统计分析各医疗卫生机构实验室的检测结果。结果全市共39家医疗卫生机构实验室参加了此次梅毒血清学质量评价活动,其中优秀21家,良好13家,合格2家,不合格3家。梅毒螺旋体血清学试验和非梅毒螺旋体血清学定性试验符合率一致,均为97.44%,非梅毒螺旋体血清学定量试验符合率只有56.41%。结论汉中市医疗卫生机构实验室梅毒血清学检测能力总体较好,但非梅毒螺旋体血清学定量检测能力还有待提高。

某安保中心数据机房空调系统设计

基于北京市某安保中心数据机房空调系统设计,介绍了数据机房室内温湿度的设计要求及空调负荷计算方法。分析了水冷冷水系统及自然冷却风冷冷水系统两种空调冷源形式的特点及优缺点并对A级机房应急冷源的设计进行了介绍。分析对比了数据机房封闭冷通道及封闭热通道的优缺点及适用性,通过气流组织分析模拟验证了封闭冷通道送风可使冷、热通道内的温度达到设计要求。针对空调冷冻水系统,提出了确定空调冷冻水供回水温度的方法,介绍了能够保证空调水系统安全运行的管路设计方法。总结了数据中心空调节能设计措施,指出了设计时应注意的事项。

试样加工方式对超高强度钢300M室温拉伸检测结果的影响

研究了四种不同的试样加工方式对300M超高强度钢室温拉伸检测结果的影响,结果表明:毛坯车成M12×Φ6.0半成品试样,然后热处理,最后磨削加工成Φ5.0的成品试样,其室温拉伸强度指标最低、塑性指标最高,能最大程度地表征材料本身的力学性能;应选用该加工方式制作300M超高强度钢的室温拉伸测试试样,其他三种加工方式强度指标偏高,均不能准确表征材料本身的力学性能。

手术室复合保温措施联合术前治疗性抚触在结肠癌根治术患者中的应用效果

目的探讨手术室复合保温措施联合术前治疗性抚触在结肠癌根治术患者中的应用效果。方法根据干预方法的不同将106例结肠癌根治术患者分为对照组和观察组,每组53例,对照组患者采取常规干预,观察组患者在对照组的基础上采取手术室复合保温措施联合术前治疗性抚触。比较两组患者的温度、焦虑情绪[状态焦虑量表(SAI)]、术后拔管时间、麻醉苏醒时间及术后并发症发生情况。结果手术30 min、1 h、2 h及术毕,观察组患者体温均明显高于对照组,差异均有统计学意义(P﹤0.01)。手术前,两组患者SAI评分均低于本组入院时,观察组患者SAI评分低于对照组,差异均有统计学意义(P﹤0.05)。观察组患者术后拔管时间、麻醉苏醒时间均短于对照组,差异均有统计学意义(P﹤0.05)。观察组患者的术后并发症总发生率低于对照组,差异有统计学意义(P﹤0.05)。结论手术室复合保温措施联合术前治疗性抚触应用于结肠癌根治术患者,可维持术中体温稳定,缓解术前焦虑情绪,促进术后麻醉苏醒,降低并发症发生率。

基于STM32的电网工控机房温湿度采集器设计

文章提出一种基于STM32对电网调度中心工控机房进行数据采集的系统,主要是实现对工控机房温湿度数据的采集与监测。使用STM32F103RBT6作为主控制器,设计和实现硬件系统。通过总线读取所测量的温湿度数据,STM32可以成功地将采集到的数据显示到OLED屏幕上并传送到上位机,同时通过蓝牙模块与手机相连,实现室内温湿度的实时采集和上传。当温湿度超过设定阈值时,采集器会通过蜂鸣器预警并将预警信息发送至手机端。实验结果表明,所设计的温湿度采集器可以准确测量工控机房内的温湿度并具备预警功能。

职业损伤对手术室护理人员的影响及防护对策

在手术室护理工作中存在许多威胁护理人员的职业损伤,主要包括物理性、化学性、生物性以及生理和心理方面的职业损伤。本文通过这些损伤对手术室护理人员造成的影响进行总结分析,并提出相对应的对策,加强护理职业安全教育,提高安全防范意识,从而达到降低护理人员职业性疾病的发生率。出现职业暴露及时按流程进行处置,采取相应的补救措施并及时上报,降低职业暴露对护理人员产生的伤害。

标准化护理在耳鼻咽喉科内镜室护理效果分析

目的:研究对耳鼻咽喉科内镜室患者实施标准化护理的临床效果。方法:选取2022年3月至2023年10月期间,南华大学附属第二医院耳鼻咽喉科内镜室患者188例,将其分为两组,各94例,参照组实施常规化护理,研究组实施标准化护理,对比两组的护理满意度测算数据值。结果:研究组的护理满意度测算数据值优于参照组(P﹤0.05)。结论:耳鼻咽喉科内镜室推进标准化护理,效果显著,值得推广。

国家电网某机房末端断水温升数值模拟与实测对比验证

对国家电网某机房进行了末端空调水阀从关闭到开启整个过程的实测与数值模拟对比研究,结果表明:冷、热通道机柜前门上温度传感器的模拟平均误差分别为3.1%和3.6%,瞬态模拟温升的整体变化趋势一致;冷通道各个传感器的逐时平均误差最大值为13.88%,平均值为9.31%。经安全运行策略分析可知,提出的优化方案能保证冷通道传感器温升极限全部在32℃以下,数值模拟可以有效预测机房IT设备的温度上升情况,减少机房温升灾难事件的发生。

家庭化产房发生医院感染的相关危险因素

目的探讨家庭化产房发生医院感染的相关危险因素及防治措施。方法回顾性选取2020年1月至2023年5月入住郑州人民医院家庭化产房的孕妇6100例,根据是否发生医院感染分为感染组(85例)和非感染组(6015例),比较两组临床资料,通过单因素及多因素logistic回归方程分析医院感染的影响因素。结果感染率为1.39%(85/6100),其中呼吸系统感染42例,生殖道感染20例,手术切口感染16例,泌尿系统感染7例。感染组体重指数≥28 kg·m^(-2)、瘢痕子宫、胎膜早破、妊娠糖尿病、妊娠高血压、白蛋白<35 g·L^(-1)、侵入性检查次数≥3次患者占比高于非感染组,白蛋白≥35 g·L^(-1)、产房定期通风患者占比低于对照组(P<0.05)。体重指数≥28 kg·m^(-2)、胎膜早破、侵入性检查次数≥3次是医院感染的高危因素,白蛋白≥35 g·L^(-1)是医院感染的保护因素(P<0.05)。模型预测感染的曲线下面积(AUC)为0.762,模型预测效能良好。结论家庭化产房产妇发生医院感染主要与体重指数、胎膜早破、侵入性检查次数、白蛋白等有关,logistic预测模型可为临床预测医院感染发生风险提供可靠参考,建议临床提前采取相应干预措施,减少医院感染发生,进而保证产妇和新生儿安全。

某实验室微纳加工平台洁净度检测结果分析

应某实验室要求,对实验室微纳加工平台进行洁净度检验检测及结果分析。采用现场检测方法,对实验室功能区及辅助用房进行洁净度、静压差、噪声、照度、温度、相对湿度、自净时间共七项参数进行现场检测。经对现场采集数据进行数据分析,该实验室洁净度ISO3.5级合格率达到100%,ISO5.5级、ISO6级、ISO7级合格率分别为80%、78%、86%,静压差检测合格率为73%,噪声检测的合格率为45%,照度检测合格率仅为13%,温度和相对湿度合格率为100%,107光刻2区自净时间为26min,206测试2区自净时间为32min。该实验室洁净卫生环境较差,应进行洁净室环境整改,加强洁净室的运行管理,对实验室的洁净度、静压差、照度、噪声等洁净指标进行严格把控,由此才能满足高精尖技术的研发进程,提高产品合格率。

镁合金棒室温拉伸试验不确定度评定

依据GB/T 228.1—2021对镁合金进行拉伸试验,并对结果进行不确定度评定。结果表明:在包含概率为95%的区间内,镁合金的抗拉强度为(343±6)MPa,其中合成标准不确定度为2.95 N/mm^(2),自由度为35,包含因子为2.03;镁合金的规定塑性延伸强度为(236±10)MPa,其中合成标准不确定度为4.53 N/mm^(2),自由度为28,包含因子为2.05;镁合金的断后伸长率为(6.0±1.0)%,其中合成标准不确定度为0.510%,自由度为24,包含因子为2.06。