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Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof
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作者 ZHU Heng-zhong XU Lei WEN Zhi-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2488-2512,共25页
This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensi... This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensive field measurement program was conducted to determine entry deformation,roof fracture zone,and anchor bolt(cable)loading.The results indicate that GSERC deformation presents asymmetric characteristics.The maximum convergence near roof cutting side is 458 mm during the primary use process and 1120 mm during the secondary reuse process.The entry deformation is closely associated with the primary development stage,primary use stage,and secondary reuse stage.The key block movement of roof cutting structure,a complex stress environment,and a mismatch in the supporting design scheme are the failure mechanism of GSERC.A controlling ideology for mining states,including regional and stage divisions,was proposed.Both dynamic and permanent support schemes have been implemented in the field.Engineering practice results indicate that the new support scheme can efficiently ensure long-term entry safety and could be a reliable approach for other engineering practices. 展开更多
关键词 gob-side entry by roof cutting ground response failure mechanism following mining states control hard main roof
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Effects of reservoir fluids on sand packs consolidated by furan and epoxy resins:Static and dynamic states
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作者 Mohammad Nabi Tabbakhzadeh Feridun Esmaeilzadeh +1 位作者 Dariush Mowla Reza Zabihi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4504-4514,共11页
One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the flu... One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again. 展开更多
关键词 Chemical sand consolidation Brine Flow rate static and dynamic states Crude oil Compressive strength Permeability Young’s modulus
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Environmental complaint insights through text mining based on the driver,pressure,state,impact,and response(DPSIR)framework:Evidence from an Italian environmental agency
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作者 Fabiana MANSERVISI Michele BANZI +5 位作者 Tomaso TONELLI Paolo VERONESI Susanna RICCI Damiano DISTANTE Stefano FARALLI Giuseppe BORTONE 《Regional Sustainability》 2023年第3期261-281,共21页
Individuals,local communities,environmental associations,private organizations,and public representatives and bodies may all be aggrieved by environmental problems concerning poor air quality,illegal waste disposal,wa... Individuals,local communities,environmental associations,private organizations,and public representatives and bodies may all be aggrieved by environmental problems concerning poor air quality,illegal waste disposal,water contamination,and general pollution.Environmental complaints represent the expressions of dissatisfaction with these issues.As the timeconsuming of managing a large number of complaints,text mining may be useful for automatically extracting information on stakeholder priorities and concerns.The paper used text mining and semantic network analysis to crawl relevant keywords about environmental complaints from two online complaint submission systems:online claim submission system of Regional Agency for Prevention,Environment and Energy(Arpae)(“Contact Arpae”);and Arpae's internal platform for environmental pollution(“Environmental incident reporting portal”)in the Emilia-Romagna Region,Italy.We evaluated the total of 2477 records and classified this information based on the claim topic(air pollution,water pollution,noise pollution,waste,odor,soil,weather-climate,sea-coast,and electromagnetic radiation)and geographical distribution.Then,this paper used natural language processing to extract keywords from the dataset,and classified keywords ranking higher in Term Frequency-Inverse Document Frequency(TF-IDF)based on the driver,pressure,state,impact,and response(DPSIR)framework.This study provided a systemic approach to understanding the interaction between people and environment in different geographical contexts and builds sustainable and healthy communities.The results showed that most complaints are from the public and associated with air pollution and odor.Factories(particularly foundries and ceramic industries)and farms are identified as the drivers of environmental issues.Citizen believed that environmental issues mainly affect human well-being.Moreover,the keywords of“odor”,“report”,“request”,“presence”,“municipality”,and“hours”were the most influential and meaningful concepts,as demonstrated by their high degree and betweenness centrality values.Keywords connecting odor(classified as impacts)and air pollution(classified as state)were the most important(such as“odor-burnt plastic”and“odor-acrid”).Complainants perceived odor annoyance as a primary environmental concern,possibly related to two main drivers:“odor-factory”and“odorsfarms”.The proposed approach has several theoretical and practical implications:text mining may quickly and efficiently address citizen needs,providing the basis toward automating(even partially)the complaint process;and the DPSIR framework might support the planning and organization of information and the identification of stakeholder concerns and priorities,as well as metrics and indicators for their assessment.Therefore,integration of the DPSIR framework with the text mining of environmental complaints might generate a comprehensive environmental knowledge base as a prerequisite for a wider exploitation of analysis to support decision-making processes and environmental management activities. 展开更多
关键词 Environmental complaints Text mining approach Term Frequency-Inverse Document Frequency(TF-IDF) DRIVER PREssURE state impact and response(DPsIR)framework semantic network analysis Regional Agency for Prevention Environment and Energy(Arpae)
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Proactive traffic responsive control based on state-space neural network and extended Kalman filter 被引量:3
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作者 过秀成 李岩 杨洁 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期466-470,共5页
The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagg... The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagging of the signal timing plans to traffic conditions. Utilizing the traffic conditions in current and former intervals, the network topology of the state-space neural network (SSNN), which is derived from the geometry of urban arterial routes, is used to predict the optimal timing plan corresponding to the traffic conditions in the next time interval. In order to improve the effectiveness of the SSNN, the extended Kalman filter (EKF) is proposed to train the SSNN instead of conventional approaches. Raw traffic data of the Guangzhou Road, Nanjing and the optimal signal timing plan generated by a multi-objective optimization genetic algorithm are applied to test the performance of the proposed model. The results indicate that compared with the SSNN and the BP neural network, the proposed model can closely match the optimal timing plans in futuristic states with higher efficiency. 展开更多
关键词 state-space neural network extended Kalman filter traffic responsive control timing plan traffic state prediction
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State Transition, Is It a Photochemical or Non-photochemical Processin Leaf in Response to Irradiance?
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作者 贾虎森 李德全 《Acta Botanica Sinica》 CSCD 2003年第12期1428-1433,共6页
The response of steady-state fluorescence (Fs) to irradiance in apple (Malus pumila Mill. cv. Tengmu No.1/Malus hupehensis Rehd.) leaf increased and decreased at light levels below and above 400 mumol(.)m(-2.)s(-1) ph... The response of steady-state fluorescence (Fs) to irradiance in apple (Malus pumila Mill. cv. Tengmu No.1/Malus hupehensis Rehd.) leaf increased and decreased at light levels below and above 400 mumol(.)m(-2.)s(-1) photosynthetic photon flux density (PPFD), respectively, while the light-adapted maximal fluorescence (Fm') and minimal fluorescence (Fo') decreased constantly with the increasing PPFD, and the closure of photosystem 11 reaction center (PS 11 RC) increased continuously, reflected by the chlorophyll fluorescence parameter of (Fs-Fo')/(Fm'-Fo'). These facts indicated that decrease of Fs above 400 mumol(.)m(-2.)s(-1) PPFD was not caused by closure of PS 11 RC, but was mainly resulted from the process of light transfer from light-harvesting complex II (LHC II) to PS II RC. In the presence of N- ethylmaleimide (NEM), an inhibitor of photosynthetic state transition, Fs kept on increasing in apple leaf at light levels from 400 to 700 mumol(.)m(-1.)s(-1), which was the photosynthetic saturation irradiance of apple leaves. In addition, Fs still increased at light levels over 700 mumol(.)m(-2.)s(-1) in apple leaf pre-treated with dithiothreitol (DTT), an inhibitor of xanthophyll cycle. These changes showed that state transition and xanthophyll cycle caused a decrease of Fs in apple leaf at light levels below and above the photosynthetic saturation irradiance, respectively. When apple leaf was pre-treated with NEM, the PS II apparent rate of photochemical reaction (P-rate) and photochemical quenching (qP) decreased significantly in the light range of 600-800 mumol(.)m(-2.)s(-1), but the non-photochemical quenching (qN) existed a small increase at 600-800 mumol(.)m(-2.)s(-1) and a decrease above 800 mumol(.)m(-2.)s(-1). These phenomena suggested that state transition was mainly a photochemical and a non-photochemical process in apple leaf responding to light lower and higher than photosynthetic saturation irradiance, respectively. 展开更多
关键词 state transition chlorophyll fluorescence light response
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2022年四川芦山M_(S)6.1地震前应力状态研究
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作者 张致伟 曾宪伟 +4 位作者 王迪 路茜 王玮铭 杨鹏 龙锋 《地震研究》 CSCD 北大核心 2024年第4期483-492,共10页
为研究2022年6月1日四川芦山M_(S)6.1地震的孕育和发生过程,采用CAP方法反演了2013年芦山M_(S)7.0主震及M_(S)≥5.0余震的震源机制解,并基于应力张量方差与b值时空分布特征,探讨了芦山M_(S)6.1地震的力学机制和震源区的应力状态。结果表... 为研究2022年6月1日四川芦山M_(S)6.1地震的孕育和发生过程,采用CAP方法反演了2013年芦山M_(S)7.0主震及M_(S)≥5.0余震的震源机制解,并基于应力张量方差与b值时空分布特征,探讨了芦山M_(S)6.1地震的力学机制和震源区的应力状态。结果表明:2022年芦山M_(S)6.1地震震源机制表现出与2013年芦山M_(S)7.0主震和5级余震相似的逆冲型破裂特征,压应力轴方位与龙门山断裂带南段区域应力场一致。2013年芦山M_(S)7.0地震后震中及附近的应力张量方差和b值长期处于低值状态,2022年芦山M_(S)6.1地震前震中及附近出现了应力张量方差和b值的低值异常,表明芦山余震区处于较高的应力水平。分析认为:巴颜喀拉块体持续东向运动受到华南块体的阻挡,震中所在区域长期受挤压逆冲作用,从而使芦山余震区长期处于应力积累的状态,芦山M_(S)6.1地震也是在这种动力学背景下发生的。 展开更多
关键词 芦山M_(s)6.1地震 芦山M_(s)7.0地震 震源机制解 应力张量方差 B值 应力状态
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国有企业ESG实践与共享价值创造——基于扎根理论的研究
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作者 朱金凤 白思祺 《技术与创新管理》 2024年第2期181-187,共7页
国有企业在我国国民经济中具有特殊重要的地位和作用,践行ESG理念对于引领国企高质量发展具有重要意义。文中采用扎根理论研究方法,构建了国有企业ESG实践与共享价值创造的理论框架,分析了ESG行为提升企业价值创造能力的作用机制。以中... 国有企业在我国国民经济中具有特殊重要的地位和作用,践行ESG理念对于引领国企高质量发展具有重要意义。文中采用扎根理论研究方法,构建了国有企业ESG实践与共享价值创造的理论框架,分析了ESG行为提升企业价值创造能力的作用机制。以中央企业华润电力为案例对象,通过对华润电力文本和数据资料的编译研究,研究证实:华润电力基于服务国家战略、回应用户诉求和探索商业机会三个履责动因,从环境管理、社会责任与公司治理三方面践行ESG理念,从而影响利益相关者选择,在这一过程中既创造了社会价值,又实现了商业价值,实现了共享价值创造。丰富了企业ESG行为经济后果的研究,为国有企业推进低碳转型,创造共享价值,实现高质量发展提供了案例证据和参考。 展开更多
关键词 扎根理论 企业社会责任 国有企业 EsG实践 共享价值创造
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2022年四川泸定 M_(s)6.8地震强震动特性研究 被引量:2
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作者 张聪 周宝峰 +4 位作者 任叶飞 王晓敏 余桦 张亚军 吴华灯 《世界地震工程》 北大核心 2024年第1期13-24,共12页
北京时间2022年9月5日12时52分,四川省甘孜州泸定县发生M_(s)6.8级地震。国家强震动台网获得了133组三分量加速度记录,在对记录进行初步筛选和滤波后,研究了PGA和PGV衰减关系、竖向地震动特点、地震动速度脉冲,对比分析了反应谱和设计谱... 北京时间2022年9月5日12时52分,四川省甘孜州泸定县发生M_(s)6.8级地震。国家强震动台网获得了133组三分量加速度记录,在对记录进行初步筛选和滤波后,研究了PGA和PGV衰减关系、竖向地震动特点、地震动速度脉冲,对比分析了反应谱和设计谱,着重对石棉挖角台站附近震害与地震动的相关性进行了分析,结论如下:1)三种台站强震动记录的PGA和PGV拟合曲线都比较相近,PGA、PGV拟合曲线与霍俊荣的预测模型较为接近;2)竖向地震动偏大,约38.2%的强震动记录V/H大于2/3,可能是屋顶塌落、柱子扭转和天花板坠落等震害现象出现的主要原因;3)识别出具有速度脉冲特性的记录11条,该类记录对长周期结构影响较大;4)所选记录反应谱大多超过了罕遇地震设计谱水平段,具有速度脉冲特性的051SMW台站周围房屋破坏较严重,人员伤亡较重。 展开更多
关键词 泸定M_(s)6.8地震 地震动衰减 竖向地震动 速度脉冲 加速度反应谱
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The Place of Human Resource Management in Lagos State Healthcare Delivery: A Statistical Overview
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作者 Maxwell Obubu Nkata Chuku +7 位作者 Alozie Ananaba Rodio Diallo Firdausi Umar Sadiq Emmanuel Sambo Oluwatosin Kolade Tolu Oyenkanmi Kehinde Olaosebikan Oluwafemi Serrano 《Health》 2023年第3期251-265,共15页
Background: Behind every great system is an organized team;this is especially true in the healthcare industry, where a dedicated human resources team can effectively recruit employees, train staff, and implement safet... Background: Behind every great system is an organized team;this is especially true in the healthcare industry, where a dedicated human resources team can effectively recruit employees, train staff, and implement safety measures in the workplace. The importance of human resources in the healthcare industry cannot be overstated, with benefits ranging from providing an orderly and effectively run facility to equipping staff with the most accurate and up-to-date training. Proper human resources management is critical in providing high-quality health care. A refocus on human resources management in healthcare requires more research to develop new policies. Effective human resources management strategies are greatly needed to achieve better outcomes and access to health care worldwide. Methods: This study leveraged NOI Polls census data on Health Facility Assessment for Lagos State. One thousand two hundred fifty-six health care facilities were assessed in Lagos State;numbers of Health workers were documented alongside their area of specialization. Also, demographic characterizations of the facilities, such as LGA, Ownership type, Facility Level Care, and Category of the facility, were also documented. Descriptive statistics alongside cross tabulation was done to present the various area of specialization of the health workers. Multiple response analysis was done to understand the distribution of human resources across the health facilities. At the same time, Chi-square and correlation tests were conducted to test the independence of various categories recorded while understanding the relationships among selected specialties. Results: The study revealed that Nurses were the most common health specialist in the Lagos State health facilities. At the same time, Gynecologists and General surgeons are the two medical specialists mostly common in health facilities. Midwives are the second most common health specialist working full time, while Generalist medical doctors make up the top three health specialists working full time. Nurses and Midwives had the highest number in Lagos State, while Pulmonologists were currently the lowest human resource available in Lagos State health care system. It was also noted that health facility distribution across Lagos’s urban and rural areas was even. In contrast, distribution based on other factors such as ownership type, Facility level of care, and facility category was slightly skewed. Conclusion: The distribution of health workers in health facility across LGA in Lagos State depend on Ownership type, Facility level of care, and category of the facility. 展开更多
关键词 Healthcare Facilities Human Resources for Health Healthcare Delivery Lagos state sDGs on Health Multiple response Analysis
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40 Hz Auditory Steady State Response to Linguistic Features of Stimuli during Auditory Hallucinations 被引量:1
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作者 应俊 闫铮 高小榕 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第5期748-753,共6页
The auditory steady state response (ASSR) may reflect activity from different regions of the brain, depending on the modulation frequency used. In general, responses induced by low rates (_〈40 Hz) emanate mostly ... The auditory steady state response (ASSR) may reflect activity from different regions of the brain, depending on the modulation frequency used. In general, responses induced by low rates (_〈40 Hz) emanate mostly from central structures of the brain, and responses from high rates (〉80 Hz) emanate mostly from the peripheral auditory nerve or brainstem structures. Besides, it was reported that the gamma band ASSR (30-90 Hz) played an important role in working memory, speech understanding and recognition. This paper investigated the 40 Hz ASSR evoked by modulated speech and reversed speech. The speech was Chinese phrase voice, and the noise-like reversed speech was obtained by temporally reversing the speech. Both auditory stimuli were modulated with a frequency of 40 Hz. Ten healthy subjects and 5 patients with hallucination symptom participated in the experiment. Results showed re- duction in left auditory cortex response when healthy subjects listened to the reversed speech compared with the speech. In contrast, when the patients who experienced auditory hallucinations listened to the reversed speech, the auditory cortex of left hemispheric responded more actively. The ASSR results were consistent with the behavior results of patients. Therefore, the gamma band ASSR is expected to be helpful for rapid and objective diagnosis of hallucination in clinic. 展开更多
关键词 auditory steady state response gamma band speech recognition auditory hallucination ELECTROENCEPHALOGRAPH
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多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结的制备及紫外探测性能研究
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作者 杜志伟 贾伟 +5 位作者 贾凯达 任恒磊 李天保 董海亮 贾志刚 许并社 《人工晶体学报》 CAS 北大核心 2024年第8期1326-1336,共11页
本文首先采用紫外光辅助电化学刻蚀(UV-EC)方法制备出了孔隙密度为1.51×10^(10)cm^(-2)、平均孔径为38 nm的多孔n-GaN薄膜;随后在其上通过水浴法沉积了一系列Zn_(x)Cu_(1-x)S复合薄膜,x为0.0、0.2、0.4、0.6、0.8、1.0,形成的多孔n... 本文首先采用紫外光辅助电化学刻蚀(UV-EC)方法制备出了孔隙密度为1.51×10^(10)cm^(-2)、平均孔径为38 nm的多孔n-GaN薄膜;随后在其上通过水浴法沉积了一系列Zn_(x)Cu_(1-x)S复合薄膜,x为0.0、0.2、0.4、0.6、0.8、1.0,形成的多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结带隙在2.34~3.51 eV调控;最后基于这些异质结构建出p-n结型紫外探测器。I-V曲线结果表明这些探测器均具有良好的整流特性,特别是n-GaN/p-Zn_(0.4)Cu_(0.6)S探测器性能最优。在暗态下,I_(+3 V)/I_(-3 V)约为1.78×10^(5);在偏压为-3 V、光功率密度为432μW/cm^(2)(365 nm)的条件下,光暗电流比超过10^(3),上升/下降时间为0.09/39.8 ms,响应度(R)为0.352 A/W,外量子效率(EQE)为119.6%,探测率(D^(*))为3.21×10^(12)Jones。I-t曲线结果表明,多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结紫外探测器在连续开-关光循环过程中拥有稳定的光电流响应。该研究为制备异质结紫外探测器提供了一定的理论指导和实验数据。 展开更多
关键词 p-Zn_(x)Cu_(1-x)s 多孔n-GaN 异质结 紫外探测器 光暗电流比 响应度
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Government's Responsibility for Control of Agricultural Environmental Pollution in China 被引量:1
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作者 Dongfang CHEN 《Asian Agricultural Research》 2016年第10期41-43,共3页
In this paper,the current situation of agricultural environmental pollution caused by the increase of chemicals input in agriculture in China was analyzed,and it is found that agricultural pollution is related to agri... In this paper,the current situation of agricultural environmental pollution caused by the increase of chemicals input in agriculture in China was analyzed,and it is found that agricultural pollution is related to agricultural industrial policies,urban-rural economic structure,funds input in pollution control,comprehensive environmental management,laws of pollution control,and so forth. To control agricultural pollution effectively,it is needed to implement integration of agricultural and environmental policies,establish environmentally friendly agricultural technology popularizing system,implement integrated planning and management of a basin,and set up and improve legislation to protect agricultural environment. 展开更多
关键词 China Agricultural environmental pollution Government’s responsibility
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Steady-state responses of a belt-drive dynamical system under dual excitations 被引量:6
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作者 Hu Ding 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期156-169,共14页
The stable steady-state periodic responses of a belt-drive system with a one-way clutch are studied. For the first time, the dynamical system is investigated under dual excitations. The system is simultaneously excite... The stable steady-state periodic responses of a belt-drive system with a one-way clutch are studied. For the first time, the dynamical system is investigated under dual excitations. The system is simultaneously excited by the firing pulsations of the engine and the harmonic motion of the foundation. Nonlinear discrete-continuous equations are derived for coupling the transverse vibration of the belt spans and the rotations of the driving and driven pulleys and the accessory pulley. The nonlinear dynamics is studied under equal and multiple relations between the frequency of the fir- ing pulsations and the frequency of the foundation motion. Furthermore, translating belt spans are modeled as axially moving strings. A set of nonlinear piecewise ordinary differ- ential equations is achieved by using the Galerkin truncation. Under various relations between the excitation frequencies, the time histories of the dynamical system are numerically simulated based on the time discretization method. Further- more, the stable steady-state periodic response curves are calculated based on the frequency sweep. Moreover, the convergence of the Galerkin truncation is examined. Numer- ical results demonstrate that the one-way clutch reduces the resonance amplitude of the rotations of the driven pul- ley and the accessory pulley. On the other hand, numerical examples prove that the resonance areas of the belt spans are decreased by eliminating the torque-transmitting in the opposite direction. With the increasing amplitude of the foun- dation excitation, the damping effect of the one-way clutch will be reduced. Furthermore, as the amplitude of the firing pulsations of the engine increases, the jumping phenomena in steady-state response curves of the belt-drive system with or without a one-way clutch both occur. 展开更多
关键词 Nonlinear vibration One-way clutch Dynamical system steady-state responses Galerkinmethod
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Quantum Mechanics: Harmonic Wave-Packets, Localized by Resonant Response in Dispersion Dynamics
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 CAS 2023年第2期171-182,共12页
From a combination of Maxwell’s electromagnetism with Planck’s law and the de Broglie hypothesis, we arrive at quantized photonic wave groups whose constant phase velocity is equal to the speed of light c = ω/k and... From a combination of Maxwell’s electromagnetism with Planck’s law and the de Broglie hypothesis, we arrive at quantized photonic wave groups whose constant phase velocity is equal to the speed of light c = ω/k and to their group velocity dω/dk. When we include special relativity expressed in simplest units, we find that, for particulate matter, the square of rest mass , i.e., angular frequency squared minus wave vector squared. This equation separates into a conservative part and a uniform responsive part. A wave function is derived in manifold rank 4, and from it are derived uncertainties and internal motion. The function solves four anomalies in quantum physics: the point particle with prescribed uncertainties;spooky action at a distance;time dependence that is consistent with the uncertainties;and resonant reduction of the wave packet by localization during measurement. A comparison between contradictory mathematical and physical theories leads to similar empirical conclusions because probability amplitudes express hidden variables. The comparison supplies orthodox postulates that are compared to physical principles that formalize the difference. The method is verified by dual harmonics found in quantized quasi-Bloch waves, where the quantum is physical;not axiomatic. 展开更多
关键词 Wave Packet Reduction Phase Velocity Hidden Variables Young’s slits Resonant response Dispersion Dynamics Quantum Physics
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强化硫化黑染色废水中S^(2-)去除的电絮凝体系
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作者 李明辉 姚继明 +1 位作者 张维 谢源 《针织工业》 北大核心 2024年第11期89-94,共6页
为提高硫化黑染色废水中S-去除效率,以镁、铁作为交替阳极,选择交流电源构建电絮凝-芬顿耦合体系。采用响应曲面法(RSM)对体系参数如施加电压、电解时间、初始pH值、H_(2)O_(2)用量进行优化设计与验证,探究其对S^(2-)去除、色度、化学... 为提高硫化黑染色废水中S-去除效率,以镁、铁作为交替阳极,选择交流电源构建电絮凝-芬顿耦合体系。采用响应曲面法(RSM)对体系参数如施加电压、电解时间、初始pH值、H_(2)O_(2)用量进行优化设计与验证,探究其对S^(2-)去除、色度、化学需氧量(COD)的影响。结果表明:H_(2)O_(2)添加量对废水COD去除率和S^(2-)去除率有一定影响,S^(2-)浓度受多因素的复合效果影响较明显。在施加电压27V、电解时间40min、初始pH值为5.9、H_(2)O_(2)为0.4mL,S^(2-)去除率最高,达到79.41%,此时COD去除率为48.08%,色度30倍。 展开更多
关键词 硫化黑染色废水 交流电絮凝 响应曲面法 s^(2-)去除率 电芬顿
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基于DPSIR模型的关中平原城市群城市人居环境韧性评价
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作者 王丽芸 杨民安 +3 位作者 钱勇生 曾俊伟 魏谞婷 王昀 《科技和产业》 2024年第17期292-300,共9页
为了研究关中平原城市群人居环境的韧性能力,通过综合权重法确定DPSIR(驱动力-压力-状态-影响-响应)模型权重,运用地理探测器和反距离空间插值法确定关中平原城市群2010—2021年城市人居环境韧性时空的分异和演变特征以及主要影响因素... 为了研究关中平原城市群人居环境的韧性能力,通过综合权重法确定DPSIR(驱动力-压力-状态-影响-响应)模型权重,运用地理探测器和反距离空间插值法确定关中平原城市群2010—2021年城市人居环境韧性时空的分异和演变特征以及主要影响因素。结果显示:驱动力是韧性水平的主要影响指数;各城市的人居环境韧性在时间序列上呈现逐渐增强的趋势,韧性指数的变化趋势显著;韧性水平在空间演化上表现以西安和咸阳为中心沿着陇海铁路为发展轴的空间发展形式;在影响因素上,教育水平、经济动力为主要因素影响人居环境韧性水平,各因素之间相互作用的影响显著。 展开更多
关键词 关中平原城市群 人居环境 韧性 DPsIR(驱动力-压力-状态-影响-响应)模型 地理探测器
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数据要素市场化配置如何影响国有企业ESG责任履行?:基于准自然实验的考察
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作者 赵放 徐熠 +2 位作者 朱梦婷 徐芝宁 马婉莹 《中国软科学》 CSSCI CSCD 北大核心 2024年第10期212-224,共13页
提升国有企业社会责任意识、完善ESG信息披露体系,充分发挥国有企业的排头兵作用是经济社会高质量发展的必然要求。研究基于2009-2022年我国沪深A股国有上市公司数据,以国家级大数据综合试验区这一外生冲击作为一项准自然实验,分析并检... 提升国有企业社会责任意识、完善ESG信息披露体系,充分发挥国有企业的排头兵作用是经济社会高质量发展的必然要求。研究基于2009-2022年我国沪深A股国有上市公司数据,以国家级大数据综合试验区这一外生冲击作为一项准自然实验,分析并检验了数据要素市场化配置对于国有企业ESG责任履行的影响和机制。研究发现:第一,随着数据要素市场化配置的加快完善,国有企业ESG责任履行不断加强;第二,数据要素市场化配置主要通过降低区域环境污染水平、提升企业信息披露质量以及资源配置效率加强国有企业ESG责任履行;第三,数据要素市场化配置对于规模较大的国有企业和非高科技国有企业ESG责任履行的促进效果更强;第四,数据要素市场化配置对于国有企业环境和治理方面的促进作用更为明显。 展开更多
关键词 数据要素市场化 国有企业 EsG责任履行 准自然实验
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Grifola frondosa polysaccharides alleviate Alzheimer's disease in rats
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作者 Samira Behrad Sina Pourranjbar +4 位作者 Mohammad Pourranjbar Saeid Abbasi-Maleki Samira Rostami Mehr Reza Hossein Gholizadeh Salmani Nasrollah Moradikor 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第11期500-506,共7页
Objective:To evaluate the effect of Grifola frondosa polysaccharides(GFP)in a rat model of Alzheimer’s disease(AD).Methods:Seventy-five rats were divided into five groups:the normal control group and the AD group tre... Objective:To evaluate the effect of Grifola frondosa polysaccharides(GFP)in a rat model of Alzheimer’s disease(AD).Methods:Seventy-five rats were divided into five groups:the normal control group and the AD group treated with or without GFP(100,200,and 400 mg/kg).Behavioral responses in the open field test and elevated plus maze test were assessed.Additionally,the levels of malondialdehyde and ferric-reducing ability of plasma,and the mRNA expressions of TNF-α,IL-6,and IL-1βin the hippocampus were measured.Results:Treatment with GFP significantly improved AD-induced behavioral changes in the open field test and elevated plus maze test(P<0.05).In addition,the level of malondialdehyde and the mRNA expressions of TNF-α,IL-6,and IL-1βwere decreased by GFP treatment in a dose-dependent manner in AD rats(P<0.05),while the level of ferric-reducing ability of plasma was significantly increased(P<0.05).Conclusions:Oral administration of GFP can reduce inflammation and oxidative stress,as well as improve behavioral responses associated with AD,suggesting its potential use in AD treatment.However,additional studies are needed to elucidate its underlying mechanisms and efficacy. 展开更多
关键词 Grifola frondosa POLYsACCHARIDEs DEMENTIA Behavioral responses INFLAMMATION Alzheimer’s disease
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DYNAMIC RESPONSE OF ELASTIC RECTANGULAR PLATES BY SPLINE STATE VARIABLE METHOD
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作者 陈荣毅 沈小璞 沈鹏程 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第6期691-698,共8页
Application of spline element and state space method for analysis of dynamic response of elastic rectangular plates is presented. The spline element method is used for space domain and the state space method in contro... Application of spline element and state space method for analysis of dynamic response of elastic rectangular plates is presented. The spline element method is used for space domain and the state space method in control theory of system is used for time domain. A state variable recursive scheme is developed, then the dynamic response of structure can he calculated directly. Several numerical examples are given. The results which are presented to demonstrate the accuracy and efficiency of the present method are quite satisfactory. 展开更多
关键词 spline element state space method dynamic response recursive scheme spline state variable method
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乌什M_(S)7.1地震引起新55井、新46井水位水温同震响应分析
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作者 贾永斌 闫玮 +1 位作者 祖丽皮牙·艾尼瓦尔 汪成国 《内陆地震》 2024年第2期158-165,共8页
为研究乌什M_(S)7.1地震引起新55井、新46井水位不同程度的响应变化,对比分析观测井水位的同震响应特征,从含水层渗透性变化和地震波能量密度探讨了同震响应机理。结果表明:①伽师新55井和乌什新46井同震响应形态主要表现为井水位的大... 为研究乌什M_(S)7.1地震引起新55井、新46井水位不同程度的响应变化,对比分析观测井水位的同震响应特征,从含水层渗透性变化和地震波能量密度探讨了同震响应机理。结果表明:①伽师新55井和乌什新46井同震响应形态主要表现为井水位的大幅快速上升。②固体潮计算分析结果表明当地震波作用于新55井和新46井时,前者垂向水力交换增强,水平向水力交换减弱,含水层的水与井水进行交换,引起井水位同震上升变化;后者含水层渗透性增加,含水层水与井水进行交换,引起井水位同震上升变化。③地震能量密度计算结果显示新55井比新46井容易触发同震响应,这种差异性的响应可能与井含水层岩性有关。 展开更多
关键词 乌什M_(s)7.1地震 新55井 新46井 水位水温 同震响应
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