Study on Repairing Permanent Transportation Roadway in Deep Mining by Bolt-Shotcrete and Mesh Supporting

The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful.

Consideration of the Self-Care Supporting Program Including Simple Exercise for Patients with Early Stages of Secondary Lower-Limb Lymphedema

Aim: We devised a self-care supporting program targeting patients with early stages of secondary lower-limb lymphedema. The program incorporates “Simple exercises to replace lymphatic drainage” based on lymphatic flow. The purpose of this study was to consider the feasibility of continuing this program. Methods: The participants were patients in the early stages of secondary lower-limb lymphedema after gynecological cancer surgery and lymphedema therapists with more than five years of experience. Patients continued self-care at home after being briefed on the program, and they were analyzed on their self-care continuity status one month later based on a self-administered questionnaire survey and self-care notes. We interviewed the lymphedema therapists about this program to discuss the feasibility of continuing it and obtain feedback. Results: The patients who participated in the study were six women who underwent surgery with lymph node dissection for gynecological cancer. The therapists were five nurses and one occupational therapist. The patient understood the importance of all items in the self-care. “Observation,” “Touching,” and “Skin care” were relatively easy to continue. “Lymph drainage” and “Exercise” were continued with “Simple exercises to replace lymphatic drainage”. “Other exercises” were able to continue by adding distance and time to daily activities. Furthermore, “Measurement” and “Recording” became a burden and were difficult to continue. Nonetheless, this program was generally approved by the lymphedema therapists. They also pointed out the content and format of the self-care notes as improvements. Conclusions: We found that the self-care supporting program that incorporated “Simple exercises to replace lymphatic drainage” might be feasible to continue self-care for patients with early stages of secondary lower-limb lymphedema. Furthermore, we found that we needed to improve the “Measurement” and “Recording” sections of this program.

Evaluation of the Performance of Financial Support for Agriculture in Guizhou Province Using Secondary Relative Benefit Model Based on DEA

We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determined by objective natural conditions, and management effectiveness of all regions (as decision-making body) in the use of financial fund for supporting agriculture. In general, there is north-south gradient difference in the performance of financial support for agriculture between regions in Guizhou Province. The drought in 2010 has significant impact on the technical efficiency in the whole province; the performance score of each item in Liupanshui City and Southwest Guizhou is very low; the technical efficiency and management efficiency in most regions need to be improved. In order to improve the performance of financial support for agriculture, we need to ensure the scale of input; at the same time, provide appropriate preferential financial policies for agricultural infrastructure, especially the construction of rural water conservancy, development and promotion of agricultural science and technology, and other fields; adopt the way of special check and acceptance of supporting projects to strengthen the use management of the fund for agriculture.

Stability Analysis of Large Section Rocky Tunnel Support Structure

In order to study the stress characteristics of the initial support and secondary lining of the large section tunnel and to solve the problem of secondary lining cracking during operation. Taking the large section tunnel in Zihong village, Qi County as the research object, a numerical simulation method was used to establish a finite element model of the large section tunnel. So as to simulate and analyze the stress characteristics of the support structure of this tunnel. Through the simulation of the initial support and second lining of this large section tunnel in terms of displacement, stress, plastic zone damage and anchor shaft force, the results show that as the excavation progresses, the stress and displacement on the surface of the newly excavated tunnel profile is faster, especially at the side walls and arch footings, the stress and displacement values are slightly larger than other characteristic points, but the final values are stable and converge, and are basically consistent with the field monitoring results, which indicates that this support system is basically in stable state. Therefore, during the tunnel excavation and support process, special attention should be paid to the stability of the sidewalls and footings, and the results of this study will be of great practical significance for tunnel construction and maintenance.

极地船型冰区强弱构件冰载荷分配

为了探究极地船型冰区结构横骨架式次要构件(骨材)与主要支撑构件(PSM)之间连接构件处的冰载荷分配规律,提出适用于骨材与PSM间连接构件处载荷的工程实用化计算方法。基于国际船级社协会极地船级规范中的设计冰载荷,提出横骨架式构件在设计冰载作用下由骨材承载分配至PSM处的载荷的工程实用化计算方法;将《散货船和油船共同结构规范》(HCSR)中的强弱构件间载荷分配方法拓展应用于极地船型冰区骨材与PSM间冰载荷分配中,在某极地科考船舯部冰带区有限元模型外板上施加设计冰载荷,根据舷侧横骨架式典型节点的应力计算出骨材与PSM间连接构件处的冰载荷值。计算结果表明,通过数值计算得到的载荷值与采用工程实用化计算方法得到的载荷值基本一致,HCSR中强弱构件间载荷分配方法可应用于极地船型中,横骨架式由骨材承载分配至PSM处的冰载荷工程实用化计算方法有效,研究结果可为后续极地船型冰区结构连接构件结构设计提供设计输入。

新时代民族地区中等职业教育的政策扶持:实践、问题、建议——以云南省为例

中等职业教育是我国民族地区普及高中阶段教育、促进产业转型发展的重要途径。新时代职业教育政策体系不断完善、工业4.0、“一带一路”倡议为云南省中等职业教育发展带来机遇,但云南省中等职业教育发展受到教育资源空间分布不均衡、教育质量亟待提升、内涵式发展意识缺失等问题的阻碍。因此,云南省在抓住机遇的同时,更要直面问题,从分区施策、改革政策与评估、打造地区精品课程和精品专业等方面应对新时代的挑战。

中职制造类专业学生学习投入对其职业认同的影响——基于领悟社会支持的中介作用

我国制造业在迈向高质量发展阶段后面临人才紧缺的发展困境,职业院校承担着培养制造业技术技能人才的关键任务。研究以10省、自治区、直辖市83所中职学校10 608名制造类专业学生为对象,通过相关量表调查了解学生学习投入、领悟社会支持和职业认同的主要特点及相关性关系。基于变量关系,研究认为提升中职制造类专业学生职业认同感还需从校企双方协同育人目标入手,同步创新人才培养模式,多方合力构建起系统全面的人才培养支持体系和权益监督保障体系,重塑技能社会文化生态,使学生产生持久的职业认同感。

从“清激调补”探讨新型冠状病毒二次感染的临证思路

结合新型冠状病毒二次感染的现状,在辨病与辨证、辨分期结合的基础上,提出“清激调补”的中医临证思路。“清”即清除外来邪毒与内生浊物,祛邪外出,是新型冠状病毒二次感染治疗的关键;“调”为调理脏腑,随证治之,是新型冠状病毒二次感染治疗的重要内容;“激”是激发人体正气,调动先天之气补充后天之气以抗邪,“补”即补益气血阴阳,“激”与“补”二者均扶正以祛邪,是促使新型冠状病毒二次感染患者恢复健康的重要手段。

Rapid vision-based system for secondary copper content estimation

A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the designed vision system. After the preprocessing and segmenting procedures, the images were selected according to their grayscale standard deviations of pixels and percentages of edge pixels in the luminance component. The selected images were then used to extract the information of the improved color vector angles, from which the copper content estimation model was developed based on the least squares support vector regression (LSSVR) method. For comparison, three additional LSSVR models, namely, only with sample selection, only with improved color vector angle, without sample selection or improved color vector angle, were developed. In addition, two exponential models, namely, with sample selection, without sample selection, were developed. Experimental results indicate that the proposed method is more effective for improving the copper content estimation accuracy, particularly when the sample size is small.

基于惯量同步的构网型永磁直驱风电机组频率支撑及转速恢复策略

针对风电机组频率响应后有功支撑与转速恢复切换易诱发二次频率跌落的问题,提出了一种考虑转速恢复的构网型风电机组频率支撑策略。首先阐述了构网型风电机组的“惯量同步”原理;其次,基于转子运动方程,分析了构网型风电机组调频及转速恢复策略对频率最低点及二次频率跌落的影响机理;最后,基于PSCAD/EMTDC仿真平台,构建基于惯量同步的构网型风电并网系统,并在不同扰动下验证所提控制策略的有效性。

基于转子动能的风电场自适应频率主动支撑控制策略

随着大规模风电接入电网,电力系统的惯性和抗扰能力逐渐下降,系统的频率稳定问题愈发严峻。为此,文中提出一种基于转子动能的风电场自适应频率主动支撑控制策略。首先,提出一种参与因子,根据风电场的平均转子转速确定风电场参与频率支撑的程度,自适应调整风电场惯性响应参数和频率下垂控制参数。在此基础上,基于风电机组的实时可用转子动能,对风电场的调频功率进行动态分配,风电机组则通过释放转子动能参与频率支撑,其可以充分发挥转子动能较多的机组的频率支撑能力,并避免转速低的风电机组过度参与调频。在频率支撑结束后,采用分阶段的转子转速恢复方法恢复机组转速。仿真结果表明,所提控制策略可以根据风电场的运行状态和风电机组可用转子动能自适应调整有功输出功率,不仅可以实现系统频率的有效支撑,还可以避免频率的二次跌落。

基于COOT算法的城轨车辆车体称重调簧算法优化

现有城轨车辆车体称重调簧模型忽略了车体的非均匀弹性变形、弹簧刚度的非线性等问题。针对该问题,文章首先建立了基于最小二乘法拟合二系支撑位刚度的改进称重调簧模型,该模型相较于传统称重调簧模型更贴合车体的实际负载情况;利用改进白骨顶鸡(COOT)算法对称重调簧算法进行多目标改造和搜索机制优化,相较于模拟退火(SA)算法、粒子群优化(PSO)算法、遗传算法(GA),改进COOT算法使稳定收敛载荷偏差分别降低了3.2 N、2.1 N和7.4 N,收敛速度分别提高了3.5%、6.8%和18.0%,具有更好的精度、效率和鲁棒性;基于C#和MATLAB搭建了整套称重调簧试验系统,并进行模拟试验及实车验证,证明了改进COOT算法及称重调簧系统的准确性和稳定性。

膨胀性软岩隧道致灾机制研究与应用

隧道建设的规模和数量迅速发展,相关理论研究却相对不足,随着隧道越来越多地穿越诸如软弱围岩、溶洞等复杂、恶劣地质区域,对施工技术和理论研究的要求也更高,如何做到规避灾害,安全施工是大家一直关注的问题。以重庆市某公路隧道为依托,对穿越膨胀性软岩段隧道,提出不良地质构造与围岩条件、水的因素、不规则地应力以及工程因素等导致隧道灾害的因素,不同因素相互关联、相互影响,根据分析结果采取相应的防治方案来规避灾害。利用Poyting-Thomoson模型计算隧道围岩变形,与现场监控量测数据相结合,对隧道膨胀性软岩段的围岩变形做出预测,得出最佳二次衬砌支护时间。同时从初支二衬间的应力角度对膨胀性软岩进行了持续监测,表明了膨胀性软岩隧道段防治方案达到了预期目标。从致灾机制来分析隧道建设,可以更好地为工程决策服务。

领悟社会支持对中职生亲社会行为的影响:希望感和感恩的链式中介作用

基于积极心理学视角,探讨领悟社会支持对中职生亲社会行为的影响机制。采用长处与困难量表、领悟社会支持量表、希望感量表、感恩量表,运用整群抽样方法,对湖南省长沙市11所中职学校学生进行问卷调查,获取1734份有效问卷。研究结果表明,领悟社会支持、希望感、感恩分别与中职生亲社会行为存在显著正相关,领悟社会支持既可以直接影响中职生的亲社会行为,又可以通过希望感或感恩的部分中介作用间接影响中职生的亲社会行为,还能通过希望感—感恩的链式中介作用对中职生的亲社会行为产生影响。基于此提出要为中职生提供多方位的社会支持,将智育与心育结合以提升学生希望水平,渗透感恩教育以强化学生感恩意识,从而使学生表现出更多的亲社会行为。

星载激光雷达望远镜主次镜支撑结构设计与分析

针对星载激光雷达望远镜的设计要求,基于超轻量化主镜组件模型结构,从材料选择、结构形式及轻量化等方面对主次镜间支撑结构及组件进行详细设计,获得次镜组件重仅为0.530 kg;主、次镜间支撑结构重仅为1.000 kg,最终获得望远镜整机结构,总重仅为10.600 kg.通过有限元建模、分析的方法,重点分析了主次镜的面型精度、相对位置关系受重力变形的影响及整机模态,保证了主次镜支撑面型RMS优于λ/40(λ@632.8 nm),整机系统具有较好的刚度和环境适应性.分析结果表明:望远镜主次镜支撑结构及组件满足设计要求,可为同类望远镜结构设计提供一定指导.

强采动巷道围岩应力演化规律研究

为了解决强动压下巷道围岩失稳的问题,利用数值模拟软件对辅助顺槽受扰动应力及位移进行分析发现,当辅运顺槽受到一次采动时,巷道顶板应力峰值小于煤柱应力峰值,煤柱的应力峰值为23.19 MPa,在二次采动影响下,煤柱应力峰值达到27.49 MPa,且二次采动相较一次采动下的煤柱应力集中有了一定扩展。同时辅运顺槽受二次采动的影响,距离工作面越小,相应的位移变形量越大,巷道顶板、底板、煤柱帮、实体煤帮的最大变形量分别为465 mm、101 mm、737 mm和216 mm。对原支护方案进行补强,经过卸压补强后支撑应力峰值为20.35 MPa,应力峰值降低了9.43%。

财政支持中等职业教育高质量发展研究——以广西为例

本文从财政支持广西中等职业教育发展的角度出发,分析广西对中等职业教育财政支持现状、问题及原因,提出加快构建融通融合融汇的现代职业教育体系,改革创新中等职业教育的财政支出机制,加快推进中等职业教育办学模式的改革,优化资源配置充分发挥筹资潜力,不断优化创新社会支持政策,建立中等职业教育财政支出绩效评价体系等对策建议。

手机成瘾与中职学生身体活动的关系——一个有调节的中介模型

目的探讨手机成瘾对中职学生身体活动的影响,以及锻炼自我效能感和同伴支持在二者中的作用及其内在联系。方法运用青少年手机使用依赖自评问卷、锻炼自我效能感量表、同伴支持量表和国际体力活动问卷对350名中职学生进行调查研究。结果1)性别和规律运动习惯与中职学生手机成瘾、身体活动和锻炼自我效能感相关显著;手机成瘾、锻炼自我效能感、身体活动两两间均呈显著相关关系;2)手机成瘾不仅直接影响中职学生的身体活动水平,还可以通过锻炼自我效能感间接影响其身体活动水平,直接效应值为-0.30,间接效应值为-0.15;3)在锻炼自我效能感与中职学生身体活动的影响链上,同伴支持具备调节效应(β=0.11,p<0.001)。结论中职学生的手机成瘾倾向越严重,身体活动水平越低;锻炼自我效能感是改善手机成瘾对身体活动影响的重要中介;同伴支持是锻炼自我效能感改善中职学生身体活动水平的促进因素。

生涯适应力对中学生学业成绩的影响机制研究

为了探讨生涯适应力对中学生学业成绩的影响及其中介机制,采用整群随机抽样的方法共收集了788名中学生的数据.研究发现生涯适应力正向预测中学生学业成绩;教师支持在生涯适应力和学业成绩之间起中介作用;未来工作自我清晰度在生涯适应力和学业成绩之间起中介作用;教师支持和未来工作自我清晰度在生涯适应力和学业成绩之间起链式中介作用.

综采工作面切巷二次扩巷技术的成功应用

为达到综采工作面安装作业空间要求,郑新公司芦沟煤矿三五井21051综采工作面安装前,采用工字钢对棚支护,对切巷进行二次扩巷,加大支护断面,增加有限作业空间,以满足综采工作面安装安全条件,保证安装作业的安全性和实用性,具有一定的借鉴和推广价值。