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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury
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作者 Mou Gao Qin Dong +3 位作者 Dan Zou Zhijun Yang Lili Guo Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1416-1430,共15页
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ... Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury. 展开更多
关键词 Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell MICROGLIA NEUROINFLAMMATION
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Synthetical condition assessment of long span suspension bridge based on closeness degree and FAHP 被引量:1
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作者 郭彤 李爱群 +1 位作者 赵大亮 王浩 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期261-265,共5页
Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a math... Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a mathematical model of a multi-objective assessment of a long span suspension bridge is set up. An example is given to show the procedure in the synthetical condition assessment of the Runyang Suspension Bridge, which includes the hierarchical division, the definition of factor weights and fuzzy membership functions, and the calculation of closeness degrees, etc. The assessment combines both the data from the health monitoring system and the manual tests. The classification of evaluation items as well as the calculation of deterministic and nondeterministic items is presented. Compared with the traditional method of point rating, this method can better describe the discreteness of monitoring data and the fuzziness in the condition assessment. 展开更多
关键词 pattern recognition fuzzy analytic hierarchy process closeness degree synthetical condition assessment suspension bridge
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基于敏感属性值语义桶分组的t-closeness隐私模型 被引量:14
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作者 张健沛 谢静 +1 位作者 杨静 张冰 《计算机研究与发展》 EI CSCD 北大核心 2014年第1期126-137,共12页
t-closeness模型是数据发布领域中用于抵御相似性攻击和偏斜攻击的一种有效方法,但其采用的EMD(earth mover's distance)距离没有考虑等价类与数据表间敏感属性分布的稳定性,不能全面地衡量分布间距离,在分布间稳定差异过大时会大... t-closeness模型是数据发布领域中用于抵御相似性攻击和偏斜攻击的一种有效方法,但其采用的EMD(earth mover's distance)距离没有考虑等价类与数据表间敏感属性分布的稳定性,不能全面地衡量分布间距离,在分布间稳定差异过大时会大大提高隐私泄露的风险.针对这种局限,提出了一种SABuk t-closeness模型,它在传统t-closeness模型的基础上,为更加准确地度量分布间距离,以EMD距离与KL散度(kullback-leibler divergence)结合构建距离度量标准.同时,根据敏感属性的层次树结构,对数据表进行语义相似性桶分组划分,然后采用贪心思想生成满足要求的最小等价类,并且运用k-近邻的思想来选取QI(quasi-identifiers)值相似的元组生成等价类.实验结果表明,SABuk t-closeness模型在牺牲少量时间的前提下减少了信息损失,能在有效地保护敏感信息不泄露的同时保持较高的数据效用. 展开更多
关键词 隐私保护 桶分组 t-closeness模型 EMD KL散度
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模糊t-closeness隐私保护方法研究 被引量:4
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作者 陈晓宇 韩斌 +1 位作者 黄树成 朱文正 《计算机应用与软件》 北大核心 2018年第9期317-322,333,共7页
针对t-closeness隐私保护方法中数据泛化机制带来的信息损失量较大的不足,基于模糊理论提出一种模糊t-closeness隐私保护方法。该方法给出数据模糊化的定义,设计并实现替代泛化机制的数据模糊化过程。该过程在模糊聚类的基础上划分出符... 针对t-closeness隐私保护方法中数据泛化机制带来的信息损失量较大的不足,基于模糊理论提出一种模糊t-closeness隐私保护方法。该方法给出数据模糊化的定义,设计并实现替代泛化机制的数据模糊化过程。该过程在模糊聚类的基础上划分出符合t-closeness隐私保护要求的模糊等价类,对元素隶属度限幅求取平均值以获取元素模糊化的替代值。同时针对元素中分类属性给出模糊化语义结构树的构造方法。进行理论证明并通过实验验证模糊t-closeness隐私保护方法降低信息损失量的同时,提高了数据的隐私保护强度。 展开更多
关键词 t—closeness 隐私保护 模糊理论 模糊化
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Dynamic Behaviors Analysis of Reduced Rotor Models with Looseness Based on the TPOD Method 被引量:1
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作者 Kuan Lu Yushu Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第4期15-30,共16页
The transient proper orthogonal decomposition(TPOD) method is used to study dynamic behaviors of the reduced rotor-bearing models,and the fault-free model is compared with the models with looseness fault.A 22 degree o... The transient proper orthogonal decomposition(TPOD) method is used to study dynamic behaviors of the reduced rotor-bearing models,and the fault-free model is compared with the models with looseness fault.A 22 degree of freedoms(DOFs) rotor model supported by bearings is established.Both one end and two ends pedestal looseness of the liquid-film bearings are studied by analyzing the time history and the frequency-spectrum curves.The effects of the initial displacement and velocity values to frequency components of the original systems and the dimension reduction efficiency are discussed.Moreover,the effects of variation of initial conditions on the efficiency of the TPOD method are studied.Reduced models can provide guidance significance from the perspectives of the theory and numerical simplification to discuss the characteristics of pedestal looseness fault. 展开更多
关键词 dimension reduction TPOD method ROTOR-BEARING Pedestal looseness HIGH-DIMENSIONAL initial values
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Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury 被引量:3
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作者 Mou Gao Qin Dong +4 位作者 Zhijun Yang Dan Zou Yajuan Han Zhanfeng Chen Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期872-880,共9页
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen... Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury. 展开更多
关键词 closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p NEUROGENESIS
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Evaluation Indexes of Degree of Closeness between Strategy and Project Portfolio Allocation
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作者 Libiao Bai Sijun Bai 《American Journal of Operations Research》 2015年第1期38-46,共9页
The main activities in project portfolio allocation management are selecting the right project components given a strategy. It is crucial to establish a scientific system of evaluation indexes to guarantee the closene... The main activities in project portfolio allocation management are selecting the right project components given a strategy. It is crucial to establish a scientific system of evaluation indexes to guarantee the closeness between strategy and project portfolio allocation optimally. With organizations growing in sizes, the functions and objectives of project components are becoming more and more different. It is necessary to set evaluation indexes of the degree of closeness from the perspectives of financial, market share, social effects, and so on according to the strategy-oriented process of project portfolio allocation. This paper proposes a project portfolio allocation process under strategic orientation and evaluation indexes of the degree of closeness between strategy and project portfolio allocation. This will help projects managers make portfolio allocation decisions. 展开更多
关键词 PROJECT PORTFOLIO ALLOCATION Evaluation Indexes DEGREE of closeness PPA Process
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Transient Response of the Starting Rotor System with the Fault of Pedestal Looseness
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作者 YAOHong-liang ZHANGXiao-wei LIUChang-li WENBang-chun 《International Journal of Plant Engineering and Management》 2004年第2期110-115,共6页
The dynamic model of a pedestal looseness rotor system is built and the dynamics of the system near the resonance region is analyzed using the KBM method. Then the asymptotic method to study a dynamic system with slow... The dynamic model of a pedestal looseness rotor system is built and the dynamics of the system near the resonance region is analyzed using the KBM method. Then the asymptotic method to study a dynamic system with slow-changing parameters is used to study the starting and braking course of the system. Finally, the analytical results are proved by experiment. The results can be used in the inspecting and fault diagnosis of a rotor system of this type. 展开更多
关键词 pedestal looseness KBM method slow-changing parameters resonance transient response
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Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft 被引量:1
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作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar close Observations and Proximity Experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system Advanced thermal management system
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Loose Body in the Knee Joint: A Case Report
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作者 Hussein Khudhur Joudi Habbal Waleed Mohammed 《Open Journal of Orthopedics》 2024年第10期436-440,共5页
Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;ho... Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;however, their complete eradication is often challenging and may not address underlying diseases, leading to persistent symptoms and the risk of new loose body formation. Aim: This case report aims to present the findings and surgical management of a 52-year-old male with an unusually large osseous loose body in the knee joint and associated pathologies. Case Presentation: The patient, a 52-year-old male, experienced recurrent episodes of severe, sudden, and painful locking of the knee joint, leading to difficulties moving. A plain MRI study was conducted to evaluate the condition of the knee joint, which revealed various degenerative changes and the presence of a loose body. Subsequently, an arthroscopic examination was performed under general anesthesia, uncovering the presence of an abnormally large loose body, as well as other pathologies including chondropathy, meniscal degeneration, and Baker’s cyst. Conclusion: Loose bodies (LBs) in the knee joint pose significant challenges and may lead to debilitating symptoms. Timely diagnosis and appropriate surgical intervention are crucial for symptom relief and the prevention of further joint damage as arthroscopic excision. Comprehensive imaging has a vital role in guiding treatment decisions and optimizing patient outcomes. In this case, the removal of the loose body improved patient outcomes and helped prevent potential joint complications. 展开更多
关键词 loose Bodies Knee Joint ARTHROSCOPY MRI Osseous loose Body Surgical Management Meniscal Degeneration Baker’s Cyst BURSITIS Osteoarthritic Changes Comprehensive Treatment
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Knowing one’s parents’ friends: association with parental closeness
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作者 何玲熹 《留学》 2019年第12期78-79,共2页
Is one knowing about their parents’social lives associated with how close they are to them?An obvious answer might be yes.We first found that in a sample of Chinese students,they are more aware of the number of frien... Is one knowing about their parents’social lives associated with how close they are to them?An obvious answer might be yes.We first found that in a sample of Chinese students,they are more aware of the number of friends their mother has tham the friends their dads have.We then found that,for girls,knowing their mom and dad's friends predicts closeness with dad.Closeness to mother is not associated with knowledge of either parents’social network.For boys,however,knowing mothers’friends(but not the father’s friends)predicts their closeness to the father.As with girls,knowing either parent’s network is not associated with maternal closeness.This research implies that there are different ways closeness emerges between mothers and fathers and their children. 展开更多
关键词 parents’social LIVES MATERNAL closeness children
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Stability analysis of loose accumulation slopes under rainfall:case study of a high‑speed railway in Southwest China
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作者 Xin Wang Qian Su +2 位作者 Zongyu Zhang Feihu Huang Chenfang He 《Railway Engineering Science》 EI 2024年第1期95-106,共12页
The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce... The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce adverse geological disasters under rainfall conditions.To ensure the smooth construction of the high-speed railway and the subsequent safe operation,it is necessary to master the stability evolution process of the loose accumulation slope under rainfall.This article simulates rainfall using the finite element analysis software’s hydromechanical coupling module.The slope stability under various rainfall situations is calculated and analysed based on the strength reduction method.To validate the simulation results,a field monitoring system is established to study the deformation characteristics of the slope under rainfall.The results show that rainfall duration is the key factor affecting slope stability.Given a constant amount of rainfall,the stability of the slope decreases with increasing duration of rainfall.Moreover,when the amount and duration of rainfall are constant,continuous rainfall has a greater impact on slope stability than intermittent rainfall.The setting of the field retaining structures has a significant role in improving slope stability.The field monitoring data show that the slope is in the initial deformation stage and has good stability,which verifies the rationality of the numerical simulation method.The research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system. 展开更多
关键词 High-speed railway loose accumulation slope Slope stability analysis Rainfall effect Strength reduction
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Research on perturbation of neutron fluence rate in a closed thermal neutron field due to medium materials
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作者 Jun-Kai Yang Ping-Quan Wang +8 位作者 Zhi-Meng Hu Fan Li Jun-Mei Zeng Lin Xiao Hong-Yu Guo Jian Zhang Giuseppe Gorini Hui Zhang Chungming Paul Chu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期222-232,共11页
The neutron radiation field has vital applications in areas such as biomedicine,geology,radiation safety,and many others for neutron detection and neutron metrology.Correcting neutron fluence rate perturbation accurat... The neutron radiation field has vital applications in areas such as biomedicine,geology,radiation safety,and many others for neutron detection and neutron metrology.Correcting neutron fluence rate perturbation accurately is an important yet challenging problem.This study proposes a correction method that analyzes three physical processes.This method,which transforms the detection process from point detection to area detection,is based on a novel physical model and has been validated through theoretical analyses,experiments,and simulations.According to the average differences between the calculated and experimental results,the new method(1.67%)demonstrated better accuracy than the traditional simulation(2.17%).In a closed thermal neutron radiation field,the detector or strong neutron absorption material significantly perturbs the neutron fluence rate,whereas its impact on the energy spectrum shape and neutron directionality is relatively minor.Furthermore,based on the calculation results of the perturbation rate formula for medium materials with different compositions and sizes,the larger the volume and capture cross section of the medium,the higher the perturbation rate generated in the closed radiation field. 展开更多
关键词 Perturbation rate Area detection Three-dimensional neutron energy spectrum closed radiation field
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Factors Associated with Closely Spaced Pregnancies at the Departmental Hospital Centre of Zou-Collines (Benin) in 2022
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作者 Klikpezo Roger Hounkponou Nouéssewa Fanny Maryline +7 位作者 Atade Sèdjro Raoul Agbegbanou Eudoxie Ahouingnan Yeyinou Salifou Badaryatou Dettin Eric Obossou Achilles Imorou Sidi Salifou Kabibou 《Open Journal of Obstetrics and Gynecology》 2024年第1期89-101,共13页
Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organiza... Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organization (WHO). The objective was to study the factors associated with closely-spaced pregnancies among women followed at the Departmental Hospital Center du Zou et du Colline (DHC/Z-C) in 2022. Study Method: This was a descriptive, analytical cross-sectional study with prospective data collection from 20 May to 30 June 2022. Results: At the end of the study, 83 of the 117 women surveyed had close pregnancies, a frequency of 70.94%. They had an average age of 27.0 ± 6.3 years and were of Fon ethnicity and related in 91.57% of cases. The majority were married (96.60%). The factors significantly associated with these closely spaced pregnancies were age between 25 and 30 years, household occupation, age at first birth, age at marriage, women’s perception of contraceptive method (CM), women’s knowledge of the existence of a center providing family planning services and non-use of MC. Conclusion: Close pregnancies are still very common in the commune of Abomey. It is therefore important to increase the use of contraceptive methods in this part of the country. 展开更多
关键词 close Pregnancy Associated Factors DHC/Z-C
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Can Closeness Established Experimentally Impact Friendship Development and Homesickness?
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作者 Christopher Russo Robin Valeri 《Psychology Research》 2015年第6期347-354,共8页
关键词 实验 合作伙伴 参与者 封闭性 操作 随访
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On Fuzzy Regularly Closed Filters in Michálek Fuzzy Topological Space
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作者 Puthenpurackal Ratnakumar Neethu Bloomy Joseph 《Advances in Pure Mathematics》 2024年第10期779-784,共6页
C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itsel... C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itself. In 1975, Michálek presented a functional definition of ordinary topology and later developed fuzzy topology as a distinct extension of this idea, setting it apart from Chang’s approach. While there has been significant research on Chang’s fuzzy topology, Michálek’s version has not received as much attention. This paper introduces the concept of fuzzy regularly closed filters, or FRCM filters, within Michálek’s fuzzy topological space and explores some properties of FRCM ultrafilters. 展开更多
关键词 TOPOLOGY Fuzzy Topology Michálek’s Fuzzy Topological Space Fuzzy closed Fuzzy Open FILTERS
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Formation of a Rapidly Rotating Classical Be-star in a Massive Close Binary System
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作者 Evgeny Staritsin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期44-50,共7页
This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by m... This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange. 展开更多
关键词 (stars:)binaries(including multiple):close stars:emission-line BE stars:early-type stars:rotation
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Sensing-Communication-Computing-Control Closed Loop for NOMA-UAV Systems
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作者 Lei Chengleyang Feng Wei +4 位作者 Wang Jue Wang Yanmin Jin Shi Yin Liuguo Ge Ning 《China Communications》 SCIE CSCD 2024年第8期89-103,共15页
In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communic... In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communication,and computing modules to support various requirements of robots.In the task process,different modules assist the robots to perform tasks in a closed-loop way,which is referred to as a sensing-communication-computing-control(SC3)loop.In this work,we investigate a UAV-aided system containing multiple SC^(3)loops,which leverages non-orthogonal multiple access(NOMA)for efficient resource sharing.We describe and compare three different modelling levels for the SC^(3)loop.Based on the entropy SC^(3)loop model,a sum linear quadratic regulator(LQR)control cost minimization problem is formulated by optimizing the communication power.Further for the assure-to-be-stable case,we show that the original problem can be approximated by a modified user fairness problem,and accordingly gain more insights into the optimal solutions.Simulation results demonstrate the performance gain of using NOMA in such task-oriented systems,as well as the superiority of our proposed closed-loop-oriented design. 展开更多
关键词 closed loop linear quadratic regulator(LQR) non-orthogonal multiple access(NOMA) power allocation unmanned aerial vehicle(UAV)
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Design and Test of Closed Hydraulic Transmission System of 4WD High-clearance Wheeled Sprayer
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作者 Hengfeng CHEN Xiaobo XU 《Plant Diseases and Pests》 2024年第3期14-20,共7页
In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic sys... In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic system that fulfills the requisite specifications should be designed.The AMESim software model is employed to construct a closed hydraulic transmission system,and the simulation analysis is then performed according to the data of hydraulic components.According to analysis results,the prototype can be optimized and upgraded,and a verification test is further carried out.The test results demonstrate that the designed closed hydraulic transmission system meets the actual working requirements of the high-clearance wheeled sprayer and provides a stable experimental platform for intelligent control of agricultural machinery. 展开更多
关键词 closed hydraulic transmission system High-clearance Wheeled sprayer Modeling and simulation Verification test
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Simulation Modelling and Techno-Economics of Supercritical Carbon Dioxide Recompression Closed Brayton Cycle
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作者 Ken Amaale Atinga 《Energy and Power Engineering》 2024年第10期325-344,共20页
In recent years, there has been global interest in meeting targets relating to energy affordability and security while taking into account greenhouse gas emissions. This has heightened major interest in potential inve... In recent years, there has been global interest in meeting targets relating to energy affordability and security while taking into account greenhouse gas emissions. This has heightened major interest in potential investigations into the use of supercritical carbon dioxide (sCO2) power cycles. Climate change mitigation is the ultimate driver for this increased interest;other relevant issues include the potential for high cycle efficiency and a circular economy. In this study, a 25 MWe recompression closed Brayton cycle (RCBC) has been assessed, and sCO2 has been proposed as the working fluid for the power plant. The methodology used in this research work comprises thermodynamic and techno-economic analysis for the prospective commercialization of this sCO2 power cycle. An evaluated estimation of capital expenditure, operational expenditure, and cost of electricity has been considered in this study. The ASPEN Plus simulation results have been compared with theoretical and mathematical calculations to assess the performance of the compressors, turbine, and heat exchangers. The results thus reveal that the cycle efficiency for this prospective sCO2 recompression closed Brayton cycle increases (39% - 53.6%) as the temperature progressively increases from 550˚C to 900˚C. Data from the Aspen simulation model was used to aid the cost function calculations to estimate the total capital investment cost of the plant. Also, the techno-economic results have shown less cost for purchasing equipment due to fewer components being required for the cycle configuration as compared to the conventional steam power plant. 展开更多
关键词 Supercritical Carbon Dioxide (sCO2) closed Brayton Cycle TECHNO-ECONOMICS Simulation Capital Expenditure Gas Turbine THERMODYNAMIC Equipment Cost Optimization and Sensitivity
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