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Challenges of a negative work load and implications on morale,productivity and quality of service delivered in NHS laboratories in England 被引量:1
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作者 Erhabor Osaro Njemanze Chima 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第6期421-429,共9页
The National Health Service(NHS)is a term used to describe the publicly funded healthcare delivery system providing quality healthcare services in the United Kingdom.There are several challenges militating against the... The National Health Service(NHS)is a term used to describe the publicly funded healthcare delivery system providing quality healthcare services in the United Kingdom.There are several challenges militating against the effective laboratory service delivery in the NHS in England.Biomedical scientists work in healthcare to diagnose disease and evaluate the effectiveness of treatment through the analysis of body fluids and tissue samples from patients.They provide the"engine room"of modern medicine with 70%of diagnosis based on the laboratory results generated by them.This review involved the search of literature for information on working condition of biomedical scientist in the NHS in England.Laboratory service delivery in the NHS in England faces numerous daunting challenges;staffing levels in the last few years have become dangerously low,less remunerated,relatively less experienced and predominantly band 5's,multidisciplinary rather than specialty based,associated with working more unsocial hours without adequate recovery time,de-banding of staff,high staff turnaround,profit and cost driven rather than quality.These factors has resulted in burn out,low morale,high sickness absences,increased error rate,poor team spirit,diminished productivity and suboptimal laboratory service delivery.There is the urgent need to retract our steps on unpopular policies to ensure that patient care is not compromised by ensuring adequate staffing level and mix,ensuring adequate remuneralion of laboratory staff,implementing evidenced-based specialty oriented service,determining the root cause/s for the high staff turnover and implementing corrective action,identifying other potential sources of waste in the system rather than pruning the already dangerously low staffing levels and promoting a quality delivery side by side cost effectiveness. 展开更多
关键词 Laboratory staffs National Health SERVICE ENGLAND NEGATIVE work load MORALE PRODUCTIVITY SERVICE delivery
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On the Study of Translation Approaches of Culture-loaded Words in Literary Works 被引量:1
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作者 李福珍 《海外英语》 2016年第23期143-144,147,共3页
Culture-loaded words refer to expressions and idioms that carry typically culture messages. The peculiarity of one culture cannot be understood or accepted by readers from another culture. The uniqueness very likely m... Culture-loaded words refer to expressions and idioms that carry typically culture messages. The peculiarity of one culture cannot be understood or accepted by readers from another culture. The uniqueness very likely makes misunderstanding and may lead to cultural vacancy in other cultures. Due to the culture differences between Chinese and English, it is hard for a translator to achieve complete equivalence at the level of word. This paper discusses the translation approaches of Chinese cultureloaded words in literary works. 展开更多
关键词 Culture-loaded Words Translation Approaches Literary works
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基于InfoWorks ICM水力模型的排水管道负荷分析方法 被引量:1
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作者 张辰 《工程建设与设计》 2025年第2期31-33,共3页
采用InfoWorks ICM水力模型,通过构建量化模型,对排水管道在不同降雨强度条件下的负荷进行分析。结果表明,新建雨水系统能满足5年一遇降雨标准,且在10年一遇降雨标准下,路面积水不超150 mm。
关键词 排水管道 负荷分析 Info works ICM 管道沉积物
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Tensile Strength Characteristics of GFRP Bars in Concrete Beams with Work Cracks under Sustained Loading and Severe Environments 被引量:4
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作者 何雄君 YANG Jingnan Charles E Bakis 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第5期934-937,共4页
To investigate the effect of different environmental conditions of GFRP bars in concrete beams with work cracks subjected to sustained loads, the beams were exposed in indoor, freeze/thaw cycles and immersed in alkali... To investigate the effect of different environmental conditions of GFRP bars in concrete beams with work cracks subjected to sustained loads, the beams were exposed in indoor, freeze/thaw cycles and immersed in alkaline solution at elevated temperature. The bars were carefully extracted from the beams and tested in order to evaluate residual tensile properties. The results show that the tensile strength decreased significantly in the highly aggressive conditions but not in the natural conditions. The effect of GFRP bars casting in concrete beams demonstrated approximately 2.5% decrease of tensile strength caused by pore water environment in concrete beams on basis of those of the original bars. The effect of sustained loading plus work cracks demonstrated about 10.5% tensile strength decrease on basis of those of the bars only casted in concrete beams. The effect of environments under sustained loading plus work cracks demonstrated about 17% tensile strength decrease caused by a saturated solution of Ca(OH)2 and 60-2 ℃ tap water (pH=12-13) and about 8% tensile strength decrease caused by freezing and thawing cycle (F/T), both on basis of those of the bars of the indoor beams only under sustained loading plus work cracks. The results demonstrate the effects of the tensile strengths under different environmental conditions of GFRP bars in concrete beams with work cracks subjected to sustained loads. 展开更多
关键词 GFRP bars concrete beams working cracks sustained loading and severe environments tensile strength
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Rolling Bearing Fault Diagnosis Based on 1D Convolutional Neural Network and Kolmogorov–Arnold Network for Industrial Internet
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作者 Huyong Yan Huidong Zhou +1 位作者 Jian Zheng Zhaozhe Zhou 《Computers, Materials & Continua》 2025年第6期4659-4677,共19页
As smart manufacturing and Industry 4.0 continue to evolve,fault diagnosis of mechanical equipment has become crucial for ensuring production safety and optimizing equipment utilization.To address the challenge of cro... As smart manufacturing and Industry 4.0 continue to evolve,fault diagnosis of mechanical equipment has become crucial for ensuring production safety and optimizing equipment utilization.To address the challenge of cross-domain adaptation in intelligent diagnostic models under varying operational conditions,this paper introduces the CNN-1D-KAN model,which combines a 1D Convolutional Neural Network(1D-CNN)with a Kolmogorov–Arnold Network(KAN).The novelty of this approach lies in replacing the traditional 1D-CNN’s final fully connected layer with a KANLinear layer,leveraging KAN’s advanced nonlinear processing and function approximation capabilities while maintaining the simplicity of linear transformations.Experimental results on the CWRU dataset demonstrate that,under stable load conditions,the CNN-1D-KAN model achieves high accuracy,averaging 96.67%.Furthermore,the model exhibits strong transfer generalization and robustness across varying load conditions,sustaining an average accuracy of 90.21%.When compared to traditional neural networks(e.g.,1D-CNN and Multi-Layer Perceptron)and other domain adaptation models(e.g.,KAN Convolutions and KAN),the CNN-1D-KAN consistently outperforms in both accuracy and F1 scores across diverse load scenarios.Particularly in handling complex cross-domain data,it excels in diagnostic performance.This study provides an effective solution for cross-domain fault diagnosis in Industrial Internet systems,offering a theoretical foundation to enhance the reliability and stability of intelligent manufacturing processes,thus supporting the future advancement of industrial IoT applications. 展开更多
关键词 Bearing fault diagnosis Kolmogorov-Arnold network adaptivity under various working load transfer generalization
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工作姿势和负荷组合对上肢疲劳交互影响效应的幅频联合分析
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作者 薛恩凯 徐红旗 《中国组织工程研究》 北大核心 2026年第16期4115-4124,共10页
背景:上肢工作相关肌肉骨骼疾患因对个人健康和社会经济的危害而备受关注,而肌肉疲劳是主要诱因。目的:通过幅频联合分析法探讨姿势和负荷交互效应对静态上肢作业中肌肉疲劳特征的影响,为上肢工作相关肌肉骨骼疾患的预防提供多维度生物... 背景:上肢工作相关肌肉骨骼疾患因对个人健康和社会经济的危害而备受关注,而肌肉疲劳是主要诱因。目的:通过幅频联合分析法探讨姿势和负荷交互效应对静态上肢作业中肌肉疲劳特征的影响,为上肢工作相关肌肉骨骼疾患的预防提供多维度生物力学依据。方法:14名健康受试者执行肩关节前屈20°,40°,60°的静态任务,任务负荷设置为其最大重复次数(1RM)的10%,30%和50%。同步采集表面肌电信号及Borg主观疲劳感知评估量表数据。采用幅频联合分析计算均方根斜率和中位频率斜率量化肌肉疲劳程度;应用配对样本t检验分析疲劳前后的疲劳状态占比;采用方差分析评估姿势、负荷及其交互效应对疲劳状态占比的影响。结果与结论:①姿势-负荷组合会显著影响作业耐受性(P<0.05),60°50%最大重复次数组合最大保持时间最短(P<0.001);②特定组合下疲劳前后肌肉疲劳状态改变:20°10%最大重复次数组合下,冈上肌和斜方肌上部疲劳状态占比显著下降(P<0.05);40°10%最大重复次数组合下,斜方肌上部疲劳状态占比差异极显著(P<0.01);③姿势与负荷对肌肉疲劳的影响相互独立,在20°姿势下,三角肌前束的疲劳占比在10%最大重复次数与30%最大重复次数、10%最大重复次数与50%最大重复次数的负荷对比中有显著性差异(P<0.05);而在10%最大重复次数负荷条件下,三角肌前束及中束的疲劳占比仅在20°与60°角度间、在疲劳前与全程阶段表现出显著性差异(P<0.05);④姿势与负荷无显著交互效应(P>0.05);⑤提示高负荷与高角度显著加速肌肉疲劳;姿势与负荷独立影响疲劳进程,二者交互效应不显著;幅频联合分析对于姿势与负荷影响下的肌肉疲劳特征敏感性有限。 展开更多
关键词 肌肉骨骼疾患 上肢疲劳 工作姿势 外部负荷 交互影响 最大保持时间 幅频联合分析
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Load Assessment of the Static Posture and Weight Holding inTerms of Pulmonary Ventilation and Heart Rate
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作者 杨磊 林宇声 +2 位作者 刘卫东 刘杰 刘鹤云 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1997年第3期156-159,共4页
The aim of this study was to explore appropriate index for load evaluation by analyzing.the changes of pulmonary ventilation (VE) and heart rate (HR)in 35 student volunteers under the condition of static posture and w... The aim of this study was to explore appropriate index for load evaluation by analyzing.the changes of pulmonary ventilation (VE) and heart rate (HR)in 35 student volunteers under the condition of static posture and weight holding.Each subject was asked to perform 7 kinds of static postures and 2 kinds of weight holdings. The HR was continuously measured by a remote detecting device. VE was recorded by a ventimeter for an average of 5 min. The results showed that HR was positively correlated to VE under static activities (r=0. 89), which suggested that VE as well as HR could to some degrees reflect the static load. It was better to use VE to indicate the load of weight holdings than to use HR, which, on the other hand, was more sensible in reflection of the posture load. It is better to use relative value of both of VE and HR to reflect the static load. In addition,arm-overheaded posture increase HR more significantly than any other activities. 展开更多
关键词 static activity pulmonary ventilation heart rate work load evaluation
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并行分治计算中的一种Work-stealing策略 被引量:2
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作者 杨际祥 谭国真 +1 位作者 王荣生 江德 《小型微型计算机系统》 CSCD 北大核心 2010年第3期408-412,共5页
在机群尤其是共享式多用户机群环境中提高非规则问题的并行计算效率是一项具有挑战性的工作.给出了一种适于多核处理器节点构成的机群的层次Work-stealing负载均衡策略(简称HWS),它能够有效利用节点的动态变化的可用计算资源.分析了分... 在机群尤其是共享式多用户机群环境中提高非规则问题的并行计算效率是一项具有挑战性的工作.给出了一种适于多核处理器节点构成的机群的层次Work-stealing负载均衡策略(简称HWS),它能够有效利用节点的动态变化的可用计算资源.分析了分治计算问题中的动态性与非规则性,并使用HWS策略对分治计算问题进行了动态负载均衡(DLB)实验.实验表明,HWS在加速比、CPU利用率和负载分布等性能指标上均优于Work-sharing和Satin-CRS策略. 展开更多
关键词 动态负载均衡(DLB) 层次work-stealing策略(HWS) 多核 分治法(D&C)
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基于SolidWorks和ADAMS的装车机械手运动仿真 被引量:25
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作者 武金艺 黄金凤 +1 位作者 李炜 田雪珂 《机床与液压》 北大核心 2016年第9期52-56,共5页
针对当今水泥装载运输行业中存在的实际问题,开发设计一种结构简单、控制容易的自动袋装水泥装车机械手。利用三维建模软件SolidWorks建立装车机械手的实体模型,将模型导入仿真软件ADAMS环境中,并进一步的添加约束和驱动等,通过对该模... 针对当今水泥装载运输行业中存在的实际问题,开发设计一种结构简单、控制容易的自动袋装水泥装车机械手。利用三维建模软件SolidWorks建立装车机械手的实体模型,将模型导入仿真软件ADAMS环境中,并进一步的添加约束和驱动等,通过对该模型进行运动学仿真分析,得到关键构件的运动学参数,绘出构件的运动特性曲线,验证机构设计的合理性和可行性,为机械手的运动控制及机械结构的优化设计提供参考依据。 展开更多
关键词 水泥装载 机械手 SOLIDworkS ADAMS 仿真
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SWN: An SDN Based Framework for Carrier Grade WiFi Networks 被引量:1
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作者 LEI Tao WEN Xiangming +3 位作者 LU Zhaoming ZHAO Xing LI Yangchun ZHANG Biao 《China Communications》 SCIE CSCD 2016年第3期12-26,共15页
With the rapid growth of mobile data traffic and vast traffic offloaded from cellular network, Wi-Fi has been considered as an essential component to cope with the tremendous growth of mobile data traffic. Although op... With the rapid growth of mobile data traffic and vast traffic offloaded from cellular network, Wi-Fi has been considered as an essential component to cope with the tremendous growth of mobile data traffic. Although operators have deployed a lot of carrier grade Wi-Fi networks, but there are still a multitude of arrears for nowadays Wi-Fi networks, such as supporting seamless handover between APs, automatic network access and unified authentication, etc. In this paper, we propose an SDN based carrier grade Wi-Fi network framework, namely SWN. The key conceptual contribution of SWN is a principled refactoring of Wi-Fi networks into control and data planes. The control plane has a centralized global view of the whole network, can perceive the underlying network state by network situation awareness(NAS) technique, and bundles the perceived information and network management operations into northbound Application Programming Interface(API) for upper applications. In the data plane, we construct software access point(SAP) to abstract the connection between user equipment(UE) and access point(AP). Network operators can design network applications by utilizing these APIs and the SAP abstraction to configure and manage the whole network, which makes carrier grade Wi-Fi networks more flexible, user-friendly, and scalable. 展开更多
关键词 SWN carrier grade Wi-Finet works SDN seamless handover load balancing Hotspot 2.0 traffic offloading
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Describing failure in geomaterials using second-order work approach
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作者 Franois Nicot Félix Darve 《Water Science and Engineering》 EI CAS CSCD 2015年第2期89-95,共7页
Geomaterials are known to be non-associated materials. Granular soils therefore exhibit a variety of failure modes, with diffuse or localized kinematical patterns. In fact, the notion of failure itself can be confusin... Geomaterials are known to be non-associated materials. Granular soils therefore exhibit a variety of failure modes, with diffuse or localized kinematical patterns. In fact, the notion of failure itself can be confusing with regard to granular soils, because it is not associated with an obvious phenomenology. In this study, we built a proper framework, using the second-order work theory, to describe some failure modes in geomaterials based on energy conservation. The occurrence of failure is defined by an abrupt increase in kinetic energy. The increase in kinetic energy from an equilibrium state, under incremental loading, is shown to be equal to the difference between the external second-order work,involving the external loading parameters, and the internal second-order work, involving the constitutive properties of the material. When a stress limit state is reached, a certain stress component passes through a maximum value and then may decrease. Under such a condition, if a certain additional external loading is applied, the system fails, sharply increasing the strain rate. The internal stress is no longer able to balance the external stress, leading to a dynamic response of the specimen. As an illustration, the theoretical framework was applied to the well-known undrained triaxial test for loose soils. The influence of the loading control mode was clearly highlighted. It is shown that the plastic limit theory appears to be a particular case of this more general second-order work theory. When the plastic limit condition is met, the internal second-order work is nil. A class of incremental external loadings causes the kinetic energy to increase dramatically, leading to the sudden collapse of the specimen, as observed in laboratory. 展开更多
关键词 Failure in geomaterials Undrained triaxial loading path Second-order work Kinetic energy Plastic limit condition Control parameter
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Compressive and Sealing Characteristics of PTFE under Cyclic Loading-unloading
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作者 张宁 LI Qiang +1 位作者 HU Kang 李青 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第1期181-184,共4页
Compressive and sealing characteristics of PTFE under cyclic loading-unloading at room temperature are studied in order to evaluate the cyclic sealing performance of control valve comprehensively. The unloading charac... Compressive and sealing characteristics of PTFE under cyclic loading-unloading at room temperature are studied in order to evaluate the cyclic sealing performance of control valve comprehensively. The unloading characteristics are different from the loading ones, therefore there is hysteresis between the unloading and loading curves. Compressive hysteresis is the main factor that causes sealing hysteresis. The leakage rate of PTFE complies with the power law before it enters the relatively stable region. Lastly, the effect of working pressure on the compressive and sealing characteristics is discussed. The experimental results show that the working pressure has little effect on compressive deformation but has a great influence on leakage rate. 展开更多
关键词 PTFE compression SEALING cyclic loading-unloading working pressure
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Mechanism of rock burst caused by fracture of key strata during irregular working face mining and its prevention methods 被引量:16
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作者 Zengqiang Yang Chang Liu +3 位作者 Hengzhong Zhu Fuxing Xie Linming Dou Jianhang Chen 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第6期889-897,共9页
To study the occurrence mechanism of rock burst during mining the irregular working face,the study took irregular panel 7447 near fault tectonic as an engineering background.The spatial fracture characteristic of over... To study the occurrence mechanism of rock burst during mining the irregular working face,the study took irregular panel 7447 near fault tectonic as an engineering background.The spatial fracture characteristic of overlying strata was analyzed by Winkler elastic foundation beam theory.Furthermore,the influence law of panel width to suspended width and limit breaking span of key strata were also analyzed by thin plate theory.Through micro-seismic monitoring,theoretical analysis,numerical simulation and working resistance of support of field measurement,this study investigated the fracture characteristic of overlying strata and mechanism of rock burst in irregular working face.The results show that the fracture characteristic of overlying strata shows a spatial trapezoid structure,with the main roof being as an undersurface.The fracture form changes from vertical‘‘O-X"type to transverse‘‘O-X"type with the increase of trapezoidal height.From the narrow mining face to the wide mining face,the suspended width of key strata is greater than its limit breaking width,and a strong dynamic load is produced by the fracture of key strata.The numerical simulation and micro-seismic monitoring results show that the initial fracture position of key strata is close to tailgate 7447.Also there is a high static load caused by fault tectonic.The dynamic and static combined load induce rock burst.Accordingly,a cooperative control technology was proposed,which can weaken dynamic load by hard roof directional hydraulic fracture and enhance surrounding rock by supporting system. 展开更多
关键词 ROCK BURST IRREGULAR working FACE Key STRATA Dynamic and static combined load Cooperative control
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Ground stability of new surface buildings erected on site above worked-out area
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作者 ZHANG Jun-ying~(1,2), WANG Jin-zhuang~1 (1.China University of Mining and Technology Beijing Campus, Beijing 100083, China 2. Tangshan Branch, China Coal Research Institute, Tangshan 063012, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期116-120,共5页
The subsided area caused by mining is expanding gradually in coal mining areas. In order to occupy less or no farmland, many mining areas are constructing or intend to erect new buildings (structures) on the ground si... The subsided area caused by mining is expanding gradually in coal mining areas. In order to occupy less or no farmland, many mining areas are constructing or intend to erect new buildings (structures) on the ground sites above the worked-out areas. The long-term safety of the new buildings is of great importance. This matter should be, therefore, handled with great care. Following an analysis of the different conditions of the worked-out areas, and the characteristics of the failure of different types of worked-out areas and their overlying strata, the cause for the occurrence of residual deformation of the surface above the worked-out area was explained. The techniques for (evaluating) the stability of ground site for erecting new buildings above worked-out area, and the technical measures for protecting such buildings were proposed. The ground stability evaluation techniques were introduced by reference to specific cases. 展开更多
关键词 worked-out area BUILDING GROUND load STABILITY measures
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锚杆动静耦合力学性能与抗冲机制
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作者 王琦 许硕 +1 位作者 江贝 刘竞轩 《煤炭学报》 北大核心 2025年第11期5043-5053,共11页
锚杆支护是深部地下工程常用的围岩控制技术。为对深部复杂条件围岩进行安全控制,需对锚杆施加预应力,同时受到围岩大变形、开采扰动和强冲击等影响,使锚杆处于动静耦合的工作状态。因此,研究锚杆在不同工作荷载状态下的抗冲性能与安全... 锚杆支护是深部地下工程常用的围岩控制技术。为对深部复杂条件围岩进行安全控制,需对锚杆施加预应力,同时受到围岩大变形、开采扰动和强冲击等影响,使锚杆处于动静耦合的工作状态。因此,研究锚杆在不同工作荷载状态下的抗冲性能与安全储备对深部地下工程支护设计至关重要。基于此,利用自主研发的锚杆动静耦合力学性能试验系统,开展了现场常用普通锚杆与高强锚杆在0~200 kN初始荷载条件下的动静耦合力学性能试验,明确了锚杆动静耦合力学性能与抗冲吸能特性。结果表明:在冲击能量方面,动静耦合条件下不同锚杆抵抗的冲击能量随初始荷载的增大具有相同的衰减规律。在吸收能量方面,锚杆的吸收总能量未随初始荷载条件改变而显著改变。同时,锚杆单次吸收能量随着初始荷载的增大而增大,导致了锚杆冲击能量显著下降,安全储备降低。在0~200 kN初始荷载条件下,普通锚杆与高强锚杆的冲击能量衰减率最大分别为58.8%、50.0%,二者吸收总能量的均值分别为13.0×10^(4)、14.4×10^(4) J,吸能系数随着强度利用率增加均呈现先缓慢、后快速的“阶段性增长”特征。通过综合分析,明确了锚杆动静耦合抗冲吸能机制,提出了锚杆动静耦合强度-能量设计理念,建立了动静耦合条件锚杆预应力“双折线”设计模型,可为深部地下工程动力灾害安全控制提供新思路。 展开更多
关键词 锚杆支护 工作荷载 动静耦合 冲击能量 吸收能量 设计理念
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PHEV副车架焊缝疲劳试验加速载荷谱研究
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作者 赵礼辉 魏绪国 +3 位作者 梁山 翁硕 冯金芝 张东东 《机械强度》 北大核心 2025年第8期1-10,共10页
针对新能源汽车副车架的焊缝疲劳试验问题,提出一种基于失效主导载荷的程序载荷谱编制方法。首先,建立后副车架有限元模型,将单位载荷下应力分布与各连接点载荷相耦合,运用结构应力法对副车架焊缝进行疲劳寿命评估,并筛选出容易失效的6... 针对新能源汽车副车架的焊缝疲劳试验问题,提出一种基于失效主导载荷的程序载荷谱编制方法。首先,建立后副车架有限元模型,将单位载荷下应力分布与各连接点载荷相耦合,运用结构应力法对副车架焊缝进行疲劳寿命评估,并筛选出容易失效的6处危险点;其次,通过对比各连接点载荷损伤大小,确定焊缝危险单元对应的失效主导连接点;然后,通过焊缝处主应力分析、时域相关性和单轴损伤贡献量确定失效主导载荷,实现多轴载荷降维,降低台架试验加载难度;最后,基于失效主导载荷输出伪损伤矩阵,挑选特征工况及其比例得到疲劳加速试验程序载荷谱,根据损伤等效原则确定其最小循环次数。数值仿真结果表明,程序载荷谱能够复现危险点损伤,且具有较高的加速系数,验证了加速试验谱的有效性。 展开更多
关键词 后副车架 焊缝疲劳 主应力分析 失效主导载荷 特征工况 程序载荷谱
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大采高工作面厚层砂岩破断运移及支架载荷特性研究
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作者 王君 王飞 宋万新 《煤炭工程》 北大核心 2025年第9期207-216,共10页
针对大采高工作面厚层砂岩顶板破断矿压显现剧烈难题,基于理论分析、相似模拟实验及现场试验,对小保当煤矿一号井大采高工作面覆岩运移及矿压显现规律进行研究。研究结果表明:液压支架工作阻力P与直接顶悬顶长度L4成反比,与基本顶悬臂... 针对大采高工作面厚层砂岩顶板破断矿压显现剧烈难题,基于理论分析、相似模拟实验及现场试验,对小保当煤矿一号井大采高工作面覆岩运移及矿压显现规律进行研究。研究结果表明:液压支架工作阻力P与直接顶悬顶长度L4成反比,与基本顶悬臂梁长度L1、回转角度θ及其基本顶上覆载荷强度成正相关;大采高一次采全高工作面一次回采期间采空区岩梁总体呈现“F”型分布,基本顶初次垮落步距约为70 m,周期垮落步距约为15 m,矿压集中系数约为1.8;二次回采期间留设煤柱周围岩梁总体呈现“T”型分布,基本顶初次垮落步距约为50 m,周期垮落步距约为15 m,矿压集中系数约为2.2,二次采动期间覆岩顶板应力集中度显著较高;煤柱区域呈现高应力集中;工作面二次采动期间支架载荷强度相较于单一采面采动期间高约21%,来压期间液压支架工作阻力增幅显著小于一次回采,此外,工作面上部临空段应力载荷显著较高;基于研究结果,生产矿井更新新型液压支架,并增大了额定工作阻力,有效提升了工作面的安全回采系数。 展开更多
关键词 大采高工作面 支架载荷 相似模拟 应力分布
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基于K-means和Adam-LSTM的机场进场航迹预测研究 被引量:1
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作者 黎宗孝 张健 +2 位作者 罗鑫悦 赵嶷飞 卢飞 《广西师范大学学报(自然科学版)》 北大核心 2025年第4期15-23,共9页
航班机组按照空中交通管制员的指令飞行,是当前空中交通的管理模式。随着航班量增加,为有效提高空中交通运行效率,同时缓解管制员工作负荷,开展基于航迹预测的智慧空管成为新课题。本文针对航班的航迹预测问题提出先分类后预测的航迹预... 航班机组按照空中交通管制员的指令飞行,是当前空中交通的管理模式。随着航班量增加,为有效提高空中交通运行效率,同时缓解管制员工作负荷,开展基于航迹预测的智慧空管成为新课题。本文针对航班的航迹预测问题提出先分类后预测的航迹预测法。采用某机场进场航班数据,首先应用K-means对航迹进行聚类和分类,接着针对每类进场航迹,构建Adam-LSTM深度学习模型,实现较高质量的航迹预测。研究结果表明,相比传统预测模型,本文方法航迹预测效果具有较大提升,研究成果可为智慧空中交通管理、异常航迹识别等提供技术支撑。 展开更多
关键词 空中交通 工作负荷 航迹预测 深度学习
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耦合焊接残余应力的横波可控震源振动器平板疲劳寿命预测 被引量:2
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作者 陈振 陈能鹏 +3 位作者 冉庆杰 王乔木 魏超成 鞠浩文 《工程设计学报》 北大核心 2025年第1期102-111,共10页
振动器平板是耦合横波可控震源振动器与大地的关键媒介,而平板齿与平板的焊接部位在地震波激发工况下受力复杂,易发生疲劳失效,导致平板的使用寿命较低。针对传统结构疲劳寿命分析方法不考虑焊接残余应力的问题,采用等应变原理建立应力... 振动器平板是耦合横波可控震源振动器与大地的关键媒介,而平板齿与平板的焊接部位在地震波激发工况下受力复杂,易发生疲劳失效,导致平板的使用寿命较低。针对传统结构疲劳寿命分析方法不考虑焊接残余应力的问题,采用等应变原理建立应力耦合准则,并对平板焊接焊缝危险部位开展焊接残余应力与工作载荷应力的耦合计算。随后,基于修正的S—N曲线和耦合应力谱,采用Miner准则分析平板在焊接残余应力与工作载荷应力耦合作用下的疲劳寿命。结果表明:在焊接残余应力与工作载荷应力的耦合作用下,平板发生疲劳破坏的工作寿命为8.69a,与实际8a工作寿命的相对误差为8.6%。耦合焊接残余应力的振动器平板疲劳寿命预测方法具有较高的精度和稳定性,可为横波可控震源的维护与优化提供新的思路与方法。 展开更多
关键词 横波可控震源 振动器平板 焊接残余应力 工作载荷应力 应力耦合 S—N曲线
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超大采高工作面装备群智能协同控制关键技术
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作者 张德生 周杰 +3 位作者 任怀伟 冯银辉 韩会军 巩师鑫 《煤炭技术》 2025年第10期1-5,共5页
为提高超大采高工作面装备群智能化水平,以曹家滩煤矿10 m超大采高工作面为例,分析了超大采高工作面装备群在围岩载荷、煤层厚度、截割阻力以及输送机煤量变化显著等复杂工作环境影响下,面临着围岩动载监测、直线度控制、工作面与超前... 为提高超大采高工作面装备群智能化水平,以曹家滩煤矿10 m超大采高工作面为例,分析了超大采高工作面装备群在围岩载荷、煤层厚度、截割阻力以及输送机煤量变化显著等复杂工作环境影响下,面临着围岩动载监测、直线度控制、工作面与超前支护装备协同控制等难题。针对上述问题,提出工作面“采-支-运”和“工作面-超前支架”协同智能开采工艺,构建基于态势变化的装备群协同控制机制;开发基于高频采样、视觉分析等先进技术的装备群工作状态监测装置,研制缓冲立柱、闭环控制油缸等新型执行机构以及运-支一体式智能化超前支护系统,构建以工艺为驱动、数据为引擎的超大采高工作面智能开采模式。研究成果将提升超大采高工作面装备群协同程度,为智能化工作面建设和产品研发提供借鉴。 展开更多
关键词 超大采高工作面 装备群 动态载荷 协同控制
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