期刊文献+
共找到27,560篇文章
< 1 2 250 >
每页显示 20 50 100
Mechanism,prevention,and control of mining-induced dynamic disasters in underground metal mines in China:Challenges and solutions
1
作者 LI Peng CAI Mei-feng +3 位作者 MIAO Sheng-jun REN Fen-hua GORJIAN Mostafa PENG Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2549-2606,共58页
Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological ... Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological problems to be solved urgently.In this article,the occurrence status and grand challenges of some typical dynamic disasters involving roof falling,spalling,collapse,large deformation,rockburst,surface subsidence,and water inrush in metal mines in China are systematically presented,the characteristics of mining-induced dynamic disasters are analyzed,the examples of dynamic disasters occurring in some metal mines in China are summarized,the occurrence mechanism,monitoring and early warning methods,and prevention and control techniques of these disasters are highlighted,and some new opinions,suggestions,and solutions are proposed simultaneously.Moreover,some shortcomings in current disaster research are pointed out,and the direction of efforts to improve the prevention and control level of dynamic disasters in China’s metal mines in the future is prospected.The integration of forward-looking key innovative theories and technologies in the abovementioned aspects will greatly enhance the cognitive level of disaster prevention and mitigation in China’s metal mining industry and achieve a significant shift from passive disaster relief to active disaster prevention. 展开更多
关键词 underground metal mines dynamic disasters MECHANISM monitoring and early warning prevention and control
在线阅读 下载PDF
Can Stomach Cancer be Prevented by Dietary Change: Preliminary Summary of Comparative Etiologic Study and Prevention 被引量:2
2
作者 张荫昌 林慧芝 +7 位作者 孙中行 白希文 Kunio Aoki Keiichi Kawai Ryuichiro Sasaki Yasunari Tsuchihashi Yoshinori Ito Nouki Watanabe 《中国医科大学学报》 CAS CSCD 1990年第S1期25-32,共8页
During 1984 to 1990, a comparative etiologic studyand primary prevention for stomach cancer was carriedout in a high risk area in Zhuanghe County of LiaoningProvince. Because of the increase of consumption of fr-esh v... During 1984 to 1990, a comparative etiologic studyand primary prevention for stomach cancer was carriedout in a high risk area in Zhuanghe County of LiaoningProvince. Because of the increase of consumption of fr-esh vegetables and fruits (Protective factors), decreaseof eating salted pork and fishes which was verified tohave strong mutagenecity (risk factors), acute inflamma-tion and erosions accompanying with chronic gastritis havegot striking improvement. At the same time, serum betac-arotene also raised gradually. The authors stressed thatimprovement of economic situation and dietary habits mayplay an important role in primary prevention of precurso-res of stomach cancer but decrease of incidence of thiscancer is an event of 30 years or more later as the letentperiod of stomach cancer is rather long. 展开更多
关键词 GASTRIC cancer high risk area DIETARY HABIT primary prevention
在线阅读 下载PDF
Optimal location and effect judgment on drainage tunnels for landslide prevention 被引量:4
3
作者 WANG Zhi-lei SHANG Yue-quan SUN Hong-yue 《Journal of Central South University》 SCIE EI CAS 2013年第7期2041-2053,共13页
An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China w... An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China were reviewed and the fimctions of drainage tunnel were categorized as catchment and interception. Numerical simulations were conducted. The results show that both catchment and interception tunnels have variation of the function in the simulation of monolayer model, which shows the reduction of permeability condition in lower layer. The function of catchment can be observed in the deep slope, while the function of interception is observed near groundwater source. By using the slope safety factor and discharge water amount as the objectives of optimal drainage tunnel location, and pore-water pressure in fixed node and section flux as the judgment for construction quality of adjacent drainage tunnel, the design principle of drainage tunnel was introduced. The K103 Landslide was illustrated as an example to determine the optimal drainage tunnel location. The measured drainage tunnel efficiency was evaluated and compared with that from the numerical analyses based on groundwater data. The results validate the present numerical study. 展开更多
关键词 drainage tunnel GROUNDWATER RAINFALL landslide prevention safety factor optimal analyses
在线阅读 下载PDF
Aware conflict detection of non-uniform memory access system and prevention for transactional memory 被引量:3
4
作者 王睿伯 卢凯 卢锡城 《Journal of Central South University》 SCIE EI CAS 2012年第8期2266-2271,共6页
Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementation... Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementations made significant performance degradation on NUMA system because they ignored the slower remote memory access. To solve this problem, a latency-based conflict detection and a forecasting-based conflict prevention method were proposed. Using these techniques, the NUMA aware TM system was presented. By reducing the remote memory access and the abort rate of transaction, the experiment results show that the NUMA aware strategies present good practical TM performance on NUMA system. 展开更多
关键词 transactional memory non-uniform memory access (NUMA) conflict detection conflict prevention
在线阅读 下载PDF
Marine disaster prevention and integrated coastal zone management
5
作者 Fuxiang Xu(许富祥) +1 位作者 Fengyu Wei(韦锋余) 《海洋预报》 北大核心 2001年第z1期86-94,共9页
Ocean is home town of wind and rain, treasury of resources. To exploit and use ocean will make great contribution to people’s existence and development. China is a great oceanic country with pre cinct sea area of 3,0... Ocean is home town of wind and rain, treasury of resources. To exploit and use ocean will make great contribution to people’s existence and development. China is a great oceanic country with pre cinct sea area of 3,000,000 km2. The eastern coastal region with only 60 km width, 15 % area and 40% of population of China, has created about 60% of GDP and has become the most developed region. But marine disaster in China is frequent and serious. From statistical data, economy loss made by surge, billow, sea ice, tsunami, red tide, oil spill, coast erosion, bay deposit, sea water intrusion, sea level rise, land salinization, sea water pollution, etc. increase quickly. Economy loss per year is one billion in the l980s, 10 billion in the l990s, exceeded 20 billion in 1996, and 30 billion in 1997. About 80% of it happened in the coastal area. So, marine disaster at present has become obstacle of society progress and economy development in coastal area. To mitigate marine disaster has become need for the economy development, also important task of the integrated coastal zone management. In this article, we briefly introduce countermeasures for marine disaster prevention, coastal zone management, and achievements made in the past 50 years, its problems now confronted, and the main countermeasures in the 21St century. 展开更多
关键词 marine DISASTER prevention integrated COASTAL ZONE management COUNTERMEASURES for prevention and MANAGEMENT
在线阅读 下载PDF
Practice and Thinking of Grid Management to Promote Crime Prevention and Control in Urban Community
6
作者 Ding Huanxiang 《学术界》 CSSCI 北大核心 2019年第2期207-216,共10页
Practice and Thinking of Grid Management to Promote Crime Prevention and Control in Urban
关键词 community CRIME prevention and control(CCPC) GRIDDING practice&improvement SOCIAL GOVERNANCE SOCIAL policy
在线阅读 下载PDF
Expert Consensus on Prevention and Treatment of COVID-19 Infection in Patients with Lung Cancer
7
作者 Non-small Cell Lung Cancer Expert Committee of Chinese Society of Clinical Oncology China Medical Education Association Jinming YU 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第3期165-176,共12页
Corona virus disease 2019(COVID-19)infection has become a major public health issue affecting human health.The main goal of epidemic prevention and control at the current stage in China is to“protect people’s health... Corona virus disease 2019(COVID-19)infection has become a major public health issue affecting human health.The main goal of epidemic prevention and control at the current stage in China is to“protect people’s health and prevent severe cases”.Patients with lung cancer who receive antitumor therapy have low immunity,and the risk of severe illness and death once infected is much higher than healthy people,so they are vulnerable to COVID-19 infection.At present,less attention has been paid to the prevention and treatment of COVID-19 infection in patients with lung cancer in domestic guidelines and consensus.Based on the published data in China and abroad,we proposed recommendations and formed expert consensus on the vaccination of COVID-19,the use of neutralizing antibodies and small molecule antiviral drugs for patients with lung cancer,for physician’s reference. 展开更多
关键词 Corona virus disease 2019 Lung neoplasms prevention Treatment Expert consensus
在线阅读 下载PDF
Research on the Legality of Information Utilization in Epidemic Prevention and Control
8
作者 Chen Yumei 《学术界》 CSSCI 北大核心 2020年第5期193-200,共8页
Big data is playing an important role in preventing,control and monitoring COVID-19,but during the process,the legality of the use of personal information shall be paid attention to.Personal information should be divi... Big data is playing an important role in preventing,control and monitoring COVID-19,but during the process,the legality of the use of personal information shall be paid attention to.Personal information should be divided into general information and sensitive information,and the use of sensitive information should take"Consent"as its legality basis.In the process of personal information collection,the subject qualification of the collection organization or personnel should be clearly defined,and the starting conditions and process specifications of the collection work should be determined.The use of personal information should be in accordance with legal provisions or agreed ways and purposes and should not violate individual privacy rights and other personality rights,and should not improperly display the"digital image"of individuals. 展开更多
关键词 pandemic prevention and control personal information protection LEGALITY consent
在线阅读 下载PDF
Competences for a culture of prevention 被引量:1
9
作者 BOLLMANN Ulrike 《西安科技大学学报》 CAS 北大核心 2016年第5期741-749,共9页
Work is changing. Traditional approaches to prevention fall short. A broader understanding of prevention and the cultural transformation associated with it mean that there are new demands on companies and their employ... Work is changing. Traditional approaches to prevention fall short. A broader understanding of prevention and the cultural transformation associated with it mean that there are new demands on companies and their employees. People and organisations need competences for this transformation; they must be empowered to create humane living and working conditions. In order for people and organisations to be able to develop competences for the transformation,appropriate structural conditions in educational institutions and workplaces must be created. These conditions should enable people to experience a feeling of competence,to feel part of something and to perceive their actions as autonomous. 展开更多
关键词 教育机构 文化转型 工作条件 文化事业
在线阅读 下载PDF
Prevention of ischemic stroke in diabetic patients
10
作者 Duan Jian-gang Chen Xiang-yan Wong Ka-sing 《中国现代神经疾病杂志》 CAS 2013年第4期257-262,共6页
糖尿病可使发生缺血性卒中的风险增加2倍以上,并且合并缺血性卒中的糖尿病患者长期预后不良。目前所采取的强力降血糖治疗并未使糖尿病患者从缺血性卒中的一级和二级预防中获益。然而,有研究显示,具有针对性的缺血性卒中危险因素管理,... 糖尿病可使发生缺血性卒中的风险增加2倍以上,并且合并缺血性卒中的糖尿病患者长期预后不良。目前所采取的强力降血糖治疗并未使糖尿病患者从缺血性卒中的一级和二级预防中获益。然而,有研究显示,具有针对性的缺血性卒中危险因素管理,特别是对不良生活方式、血糖、高血压、脂质代谢紊乱的干预,可预防糖尿病患者缺血性卒中的发生,并改善预后。在符合干预标准的糖尿病患者中,抗血栓治疗和颈动脉外科手术对缺血性卒中的一级和二级预防是必要的。本文拟对近年公布的糖尿病患者缺血性卒中一级和二级预防的相关证据进行概述,使临床医师了解该领域的研究现状与动态,从而更好地实施糖尿病患者的卒中预防措施。 展开更多
关键词 脑缺血 卒中 预防 糖尿病
在线阅读 下载PDF
中国卒中预防20年 被引量:1
11
作者 张润华 李天琪 +2 位作者 翟屹 姜勇 刘改芬 《中国卒中杂志》 北大核心 2025年第5期581-594,共14页
预防卒中发生是降低卒中疾病负担的根本途径。作为多因素共同作用所致疾病,卒中的发病机制涉及生活方式、遗传及环境等多种危险因素,控制危险因素是降低卒中发病率的核心策略。无论是针对未患病群体的卒中一级预防,还是针对卒中患者的... 预防卒中发生是降低卒中疾病负担的根本途径。作为多因素共同作用所致疾病,卒中的发病机制涉及生活方式、遗传及环境等多种危险因素,控制危险因素是降低卒中发病率的核心策略。无论是针对未患病群体的卒中一级预防,还是针对卒中患者的二级预防,在卒中防治管理中都具有重要价值。本文系统梳理中国近20年来卒中预防的发展历程,重点呈现以下3方面研究成果:基于流行病学数据,系统总结中国卒中重要危险因素的流行趋势及变化特征;总结卒中二级预防中药物干预的执行情况,重点介绍抗血小板治疗的进展,回顾卒中预防领域具有里程碑意义的临床研究及其对临床实践的指导价值;总结和描述中国卒中筛查体系及防控策略的演进路径。此外,本文还对未来的卒中预防技术发展和研究方向进行展望:可穿戴医疗设备、人工智能辅助决策等新兴技术为卒中预防提供了新的工具,但这些新技术的应用效果及推广价值仍有待大规模临床研究进一步验证。 展开更多
关键词 卒中 预防 一级预防 二级预防
在线阅读 下载PDF
Communication error prevention model in industrial organization
12
作者 SHI Gui-rong 《西安科技大学学报》 CAS 北大核心 2016年第5期732-736,共5页
In this study,the communication error generation mechanism was analyzed from the view of human's psychological trait and organizational behavior,based on the basic process of communication,and the individual facto... In this study,the communication error generation mechanism was analyzed from the view of human's psychological trait and organizational behavior,based on the basic process of communication,and the individual factors and organizational factors which cause communication errors were examined.Communication error doesn't just say that there was just a slip in transport of information(misinformation),the behavior which information wasn't conveyed or which couldn't be transported is also included(non-information). To prevent communication error,it's necessary to consider from the individual personal level and the organizational level based on a process of communication. The model to prevent communication error in the industrial organization was tried to propose by this consideration. In recent years,the trouble and accident by nonverbal communication which doesn't depend on language often generate at a work site. It should be considered as future's problem how to prevent such communication error,based on the environment of the work site and the situation. 展开更多
关键词 组织行为学 通信行业 人际交流 通信错误
在线阅读 下载PDF
中国慢性乙型肝炎治疗的进展与挑战 被引量:5
13
作者 单姗 贾继东 《临床肝胆病杂志》 北大核心 2025年第2期205-209,共5页
我国自1992年开始实行了以新生儿普遍接种乙型肝炎疫苗为核心的综合预防策略,极大地降低了人群(特别是低年龄组人群)中乙型肝炎病毒表面抗原阳性率。抗病毒治疗不仅可以改善肝脏组织学,而且还可以减少肝硬化及门静脉高压相关并发症及肝... 我国自1992年开始实行了以新生儿普遍接种乙型肝炎疫苗为核心的综合预防策略,极大地降低了人群(特别是低年龄组人群)中乙型肝炎病毒表面抗原阳性率。抗病毒治疗不仅可以改善肝脏组织学,而且还可以减少肝硬化及门静脉高压相关并发症及肝细胞癌的发生风险,从而改善临床预后。随着临床指南不断更新以及一线抗病毒药物价格大幅下降,治疗的可及性和可负担性大幅提高。但由于我国人口基数大、既往乙型肝炎流行率高,现存乙型肝炎感染人数仍然众多,诊断率和治疗率仍然偏低,乙型肝炎相关肝硬化和肝癌人群死亡率仍较高。因此,应通过积极的社会动员并采取医防结合的策略,开展大规模检测和治疗慢性乙型肝炎,助力实现世界卫生组织提出的2030年消除病毒性肝炎公共卫生危害的目标。 展开更多
关键词 乙型肝炎 预防 治疗学
在线阅读 下载PDF
患者病历在医疗纠纷处理实践中的问题与对策 被引量:1
14
作者 杨超 胡燕生 +5 位作者 李丽华 郑雪倩 高树宽 童云洪 邓利强 王婧 《中国医院》 北大核心 2025年第3期93-97,共5页
《医疗纠纷预防和处理条例》颁布实施5年来,对于医疗纠纷预防和解决、保障患者权益、提高医疗质量和医院管理水平具有重要指导意义。鉴于医疗纠纷处理实践中关于病历的法律属性和责任承担的争议不断,对病历与病案的区别、复印病历的主... 《医疗纠纷预防和处理条例》颁布实施5年来,对于医疗纠纷预防和解决、保障患者权益、提高医疗质量和医院管理水平具有重要指导意义。鉴于医疗纠纷处理实践中关于病历的法律属性和责任承担的争议不断,对病历与病案的区别、复印病历的主体、电子病历的法律适用以及手术录像的法律适用等7个问题进行分析探讨。在此基础上,提出相关建议,旨在厘清病历的法律属性,强化病历在医疗纠纷预防与处理中的标准化共识,为提高医疗机构病历管理水平、强化医疗质量和安全提供有意义的借鉴。 展开更多
关键词 病历 医疗纠纷预防和处理条例 医疗纠纷 纠纷预防
在线阅读 下载PDF
外来植物刺果瓜的入侵策略与防治研究进展 被引量:2
15
作者 张梅 丛培东 +2 位作者 刘宇嘉 王鹏 刘利 《生物安全学报(中英文)》 北大核心 2025年第1期27-33,共7页
刺果瓜是原产于美国东北部的一年生草质藤本攀援植物,最初因其观赏价值高而被广泛种植,现已扩散至欧洲、亚洲的部分国家和地区,给当地植物的生长造成严重威胁。由于入侵性极强,刺果瓜已经演变成有害的入侵杂草,严重危害我国农业生产、... 刺果瓜是原产于美国东北部的一年生草质藤本攀援植物,最初因其观赏价值高而被广泛种植,现已扩散至欧洲、亚洲的部分国家和地区,给当地植物的生长造成严重威胁。由于入侵性极强,刺果瓜已经演变成有害的入侵杂草,严重危害我国农业生产、城市绿化及生态环境。目前,对刺果瓜的入侵策略尚无系统的认识,本文通过综述刺果瓜的分布危害、营养和繁殖生长策略、竞争策略以及防治应用等研究现状,归纳其入侵策略和防治进展,以期为刺果瓜的防治工作提供参考。结果发现:刺果瓜成功入侵的关键在于多样化的适应策略和较强的传播扩散能力;其对农业生产及生态环境造成危害的主要原因在于攀援绞杀性和占据不同生态位;刺果瓜防治主要包括人工拔除、化学和生物防治等方法;刺果瓜在土壤修复、医药价值、农业利用等方面已有所应用。未来应加强刺果瓜在自然生境中的适应机制、应用开发和防治技术等研究。 展开更多
关键词 刺果瓜 外来植物 入侵策略 防治 利用
在线阅读 下载PDF
采空区煤自燃与瓦斯复合灾害防控研究进展及挑战 被引量:11
16
作者 秦波涛 马东 《煤炭学报》 北大核心 2025年第1期392-408,共17页
采空区煤自燃与瓦斯复合灾害是煤矿最严重的灾害之一,往往会造成重大的人员伤亡和经济损失。为了进一步提高防控采空区复合灾害的能力,分析了采空区的漏风、瓦斯运移集聚和煤自燃火灾是发生煤自燃与瓦斯复合灾害的主要形成要素,指出了... 采空区煤自燃与瓦斯复合灾害是煤矿最严重的灾害之一,往往会造成重大的人员伤亡和经济损失。为了进一步提高防控采空区复合灾害的能力,分析了采空区的漏风、瓦斯运移集聚和煤自燃火灾是发生煤自燃与瓦斯复合灾害的主要形成要素,指出了复合灾害具有耦合性、隐蔽性、不确定性、动态性、继发性和严重性的主要特征;提出了复合灾害防控技术体系,系统阐述了目前我国在煤自燃与瓦斯复合灾害动态演化特性、复合灾害辨识与预警技术、采空区绿色高效防灭火技术、复合灾害惰化抑爆技术和复合灾害应急处置技术等方面的最新研究成果及进展。但是,随着我国煤矿开采深度和强度的增大,开采环境发生剧烈变化,采空区复合灾害问题也日趋严重复杂,采空区煤自燃诱发瓦斯爆炸的重特大事故仍时有发生。针对采空区煤自燃与瓦斯复合灾害高效防控的迫切需求,通过分析最近发生的采空区煤自燃与瓦斯复合灾害事故,凝练出复合灾害耦合致灾风险的精准预判与评估、复合灾害信息的精准获取、封闭区域的合理选择、灾害区域的精准定位和智能定向处置是当前复合灾害高效防控面临的四大挑战,并提出了相应的研究方向和内容,为防范与遏制采空区煤自燃与瓦斯复合灾害事故、保障我国煤炭安全高效开采提供借鉴。 展开更多
关键词 采空区 复合灾害 煤炭自燃 瓦斯爆炸 灾害防控
在线阅读 下载PDF
胃癌的科学预防、早期诊断与精准治疗 被引量:2
17
作者 王斌 王涛 《陆军军医大学学报》 北大核心 2025年第5期385-395,共11页
我国胃癌防治工作面临发病率高、疾病负担重、防控体系待完善等多重挑战,构建“预防-诊断-治疗”三位一体的精准防控体系已成为当务之急。在疾病预防维度,基于循证医学的幽门螺旋杆菌根除治疗展现出显著优势;高危肠上皮化生的内镜诊断... 我国胃癌防治工作面临发病率高、疾病负担重、防控体系待完善等多重挑战,构建“预防-诊断-治疗”三位一体的精准防控体系已成为当务之急。在疾病预防维度,基于循证医学的幽门螺旋杆菌根除治疗展现出显著优势;高危肠上皮化生的内镜诊断新技术已启动临床转化,可精准识别高危肠上皮化生等癌前病变。诊断技术创新方面,新近报道的内镜分子成像和液体活检等早期胃癌筛查新技术能显著提升检出率。治疗策略优化层面,免疫、靶向和放疗等综合治疗以及基于分子分型的个性化治疗新策略,为不同分子亚型的胃癌患者带来临床获益。当前,高通量多组学测序与人工智能技术紧密融合;未来,这些新兴技术有望加快解决胃癌防控领域的诸多关键科学问题,促进基础与临床研究的跨越式发展,推动我国胃癌防治从经验医学、循证医学向精准医学的范式转变,最终实现发病率和病死率“双下降”的“健康中国”宏伟目标。 展开更多
关键词 胃癌 预防 早期诊断 治疗 精准医学
在线阅读 下载PDF
我国不同类别煤层底板水害致灾机理与防控远景导向 被引量:8
18
作者 曾一凡 朱慧聪 +9 位作者 武强 王厚柱 傅先杰 王铁记 王玺瑞 樊九林 胡荣杰 才向军 阚雪冬 高生保 《煤炭学报》 北大核心 2025年第2期1073-1099,共27页
我国成煤条件苛刻,赋煤环境复杂多变,资源呈全域性跨多地质类型、点散式分布,导致回采共(伴)生地质灾害频现。同时,伴随煤炭资源开发布局优化调控,煤层底板水害负面导向性越趋显著,高承压水水力驱动及强敏感性缺陷构造活化的协同作用导... 我国成煤条件苛刻,赋煤环境复杂多变,资源呈全域性跨多地质类型、点散式分布,导致回采共(伴)生地质灾害频现。同时,伴随煤炭资源开发布局优化调控,煤层底板水害负面导向性越趋显著,高承压水水力驱动及强敏感性缺陷构造活化的协同作用导致煤层底板水害宏观动力学表象威胁性显著提升,成为我国煤炭资源高质量转型发展的内生阻力。为全方位掌握我国煤层底板水害发展形势,探讨未来基于新技术开展防控作业的重点攻关方向,从时间、空间、突水量等多维视角下全方位展示了近年来我国煤层底板水害动态演变趋势,对类型进行了“总−分”式细划,并通过建立地质力学模型探讨了我国煤层底板水害力学互馈响应机制,基于灾害宏观表象等揭示了其内生致灾机理,指出了防控技术理念的新发展路径和远景导向。研究发现:统计分析了我国煤层底板水害多维视角下的演变规律和特征,探讨建立了我国煤层底板水害主体架构,依据事故核心致因体系及宏观致灾表象等将煤层底板水害划分为岩溶陷落柱突水、断层活化突水及裂隙导升(复合)灰岩水突涌3大类,进一步细化为全路径贯通增量导升型突水(岩溶陷落柱)、贯穿煤层型突水(断层)、单层随采卸荷直接型突水(裂隙)等12个子类,并针对性的独立分析了3个大类煤层底板水害地理空间分布规律;分析了地应力和承压水水压对岩溶陷落柱突水过程承压水导升路径异化发育作用机制,提出了覆岩顶板动/静载扰动诱发底板岩溶陷落柱突水模式,阐明了其力学启动条件及致灾机理;建立了煤层底板断层宏细观地质力学构造概化模型,基于诱发断层活化突水的核心致灾诱因识别并建立了不同类别煤层底板断层活化突水力学判据;以裂隙为基础单元,“由1至n”式建立了单一层位和复合层位承压含水层诱发裂隙型导升(复合)灰岩水突涌的临界判别条件,揭示了该类型底板水害全过程致灾机理;在总结现行煤层底板水害探查、预测及控制技术理念基础上,结合前沿发展方向,指出并建议在煤层底板本底地质基因的全生命周期采动诱变特征三维动态重构、适用于时空分异动态地质环境的煤层底板突水预测预报理念升级、低扰动强干预的随采随治保/控水互馈注浆治理技术应用、修复后地质生态系统长效监控诊断诊疗平台建立等方面展开攻关,构建煤层底板水害全时空防控大体系,紧跟新质生产力大背景下全煤行业新业态发展步伐。 展开更多
关键词 矿井水防治 底板水害 岩溶陷落柱 断层 致灾机理
在线阅读 下载PDF
基于CSD-STM的风电机马尔可夫链退化建模与预防维护策略 被引量:1
19
作者 李亚平 李海燕 陶良彦 《计算机集成制造系统》 北大核心 2025年第2期627-636,共10页
针对现有的风电机马尔可夫链退化建模方法忽视了外部冲击的影响,设计了一类考虑累积冲击损伤的状态概率转移矩阵(CSD-STM),在此基础上研究了基于CSD-STM的风电机马尔可夫链退化建模方法,并定义了可靠度模型,同时提出基于收益最大化的预... 针对现有的风电机马尔可夫链退化建模方法忽视了外部冲击的影响,设计了一类考虑累积冲击损伤的状态概率转移矩阵(CSD-STM),在此基础上研究了基于CSD-STM的风电机马尔可夫链退化建模方法,并定义了可靠度模型,同时提出基于收益最大化的预防维护策略,为风电机的可靠度评估与预防维护决策提供了理论支撑。最后通过风电发电机案例分析验证了所提模型与方法的有效性。 展开更多
关键词 外部冲击 马尔可夫链 可靠性 预防维护
在线阅读 下载PDF
井口简易防喷器密封胶芯形变及其密封特性分析 被引量:1
20
作者 郑刚 刘新福 +3 位作者 刘广胜 魏韦 邓泽鲲 刘春花 《机床与液压》 北大核心 2025年第1期140-145,共6页
分析油液压力小于15 MPa的井口简易防喷器密封胶芯形变规律及其密封特性,对降低防喷器压力等级、防止井口失控以及尽可能减少井口非可控时间具有重要意义。依据Lindly模型,提出密封胶芯发生大、小变形时的形变改进计算方法。综合考虑油... 分析油液压力小于15 MPa的井口简易防喷器密封胶芯形变规律及其密封特性,对降低防喷器压力等级、防止井口失控以及尽可能减少井口非可控时间具有重要意义。依据Lindly模型,提出密封胶芯发生大、小变形时的形变改进计算方法。综合考虑油液压力变化、受压力与变形关系、不同阶段橡胶压缩量等因素以及壳体和闸板等结构参数,建立密封胶芯形变以及橡胶体主要面应力和抱紧力的数学模型。根据修正的Arruda-Boyce模型,揭示密封胶芯橡胶体本构模型的应力应变关系。结果表明:井口简易防喷器中部密封胶芯橡胶体环状部分的最大应力位于圆弧区域,且该区域内应力分布极不均匀;井口无压力时,中部密封胶芯橡胶体环状部分的Mises应力集中于中间位置,压力为3、10 MPa时,Mises应力集中在上下两个边缘区域,且橡胶体平面部分的中部区域应力随压力增大呈下降趋势;上部密封胶芯上部橡胶体的应力分布呈边缘大中间小的特征,上部密封胶芯较大应力分布区域的面积在闸板总成关闭时明显减小,且集中区域由开启时靠近壳体边缘和2个边角处转变为关闭时的4个边角处,且最大应力由开启状态下的2.95 MPa增加至关闭状态下的3.37 MPa。 展开更多
关键词 简易防喷器 密封胶芯 形变 密封特性 本构模型
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部