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OptimizationDesign and Numerical Simulation of Variable Tube Diameter Heat Exchanger for Split Air Conditioning Indoor Unit
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作者 Zheming Cheng Xinping Ou Yang +2 位作者 Leren Tao Zihao Wang Ke Sun 《Frontiers in Heat and Mass Transfer》 2026年第1期288-313,共26页
Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers of... Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers offer advantages such as reduced material usage,lower refrigerant charge,and compact structure.However,they also face challenges,including increased refrigerant pressure drop and smaller heat transfer area inside the tubes.This paper combines the advantages and disadvantages of both small and large-diameter tubes and proposes a combined-diameter heat exchanger,consisting of large and small diameters,for use in the indoor units of split-type air conditioners.There are relatively few studies in this area.In this paper,A theoretical and numerical computation method is employed to establish a theoretical-numerical calculation model,and its reliability is verified through experiments.Using this model,the optimal combined diameters and flow path design for a combined-diameter heat exchanger using R32 as the working fluid are derived.The results show that the heat transfer performance of all combined diameter configurations improves by 2.79%to 8.26%compared to the baseline design,with the coefficient of performance(COP)increasing from 4.15 to 4.27~4.5.These designs can save copper material,but at the cost of an increase in pressure drop by 66.86%to 131.84%.The scheme IIIH,using R32,is the optimal combined-diameter and flow path configuration that balances both heat transfer performance and economic cost. 展开更多
关键词 Split air condition variable tube diameter enhanced heat transfer numerical simulation structural design optimization
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The potential mechanism and clinical application value of remote ischemic conditioning in stroke 被引量:3
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作者 Yajun Zhu Xiaoguo Li +6 位作者 Xingwei Lei Liuyang Tang Daochen Wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo 《Neural Regeneration Research》 SCIE CAS 2025年第6期1613-1627,共15页
Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may... Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved. 展开更多
关键词 Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke NEUROINFLAMMATION neuroprotection Notch1 PI3K remote ischemic conditioning STROKE
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Optimization method of conditioning factors selection and combination for landslide susceptibility prediction 被引量:3
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作者 Faming Huang Keji Liu +4 位作者 Shuihua Jiang Filippo Catani Weiping Liu Xuanmei Fan Jinsong Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期722-746,共25页
Landslide susceptibility prediction(LSP)is significantly affected by the uncertainty issue of landslide related conditioning factor selection.However,most of literature only performs comparative studies on a certain c... Landslide susceptibility prediction(LSP)is significantly affected by the uncertainty issue of landslide related conditioning factor selection.However,most of literature only performs comparative studies on a certain conditioning factor selection method rather than systematically study this uncertainty issue.Targeted,this study aims to systematically explore the influence rules of various commonly used conditioning factor selection methods on LSP,and on this basis to innovatively propose a principle with universal application for optimal selection of conditioning factors.An'yuan County in southern China is taken as example considering 431 landslides and 29 types of conditioning factors.Five commonly used factor selection methods,namely,the correlation analysis(CA),linear regression(LR),principal component analysis(PCA),rough set(RS)and artificial neural network(ANN),are applied to select the optimal factor combinations from the original 29 conditioning factors.The factor selection results are then used as inputs of four types of common machine learning models to construct 20 types of combined models,such as CA-multilayer perceptron,CA-random forest.Additionally,multifactor-based multilayer perceptron random forest models that selecting conditioning factors based on the proposed principle of“accurate data,rich types,clear significance,feasible operation and avoiding duplication”are constructed for comparisons.Finally,the LSP uncertainties are evaluated by the accuracy,susceptibility index distribution,etc.Results show that:(1)multifactor-based models have generally higher LSP performance and lower uncertainties than those of factors selection-based models;(2)Influence degree of different machine learning on LSP accuracy is greater than that of different factor selection methods.Conclusively,the above commonly used conditioning factor selection methods are not ideal for improving LSP performance and may complicate the LSP processes.In contrast,a satisfied combination of conditioning factors can be constructed according to the proposed principle. 展开更多
关键词 Landslide susceptibility prediction conditioning factors selection Support vector machine Random forest Rough set Artificial neural network
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Exploration of the Application of Remote Ischemic Conditioning in Nursing of Cardiac Arrest
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作者 Yi-maizi Xu Mingyue Yang +3 位作者 Fangchi Liu Chao Zhang Yimeng Yan Zhixian Feng 《Journal of Clinical and Nursing Research》 2025年第4期121-129,共9页
Cardiac arrest(CA)is a major global public health challenge,and its high morbidity and low survival rate pose severe tests for emergency and critical care.Although modern CPR techniques significantly improve the immed... Cardiac arrest(CA)is a major global public health challenge,and its high morbidity and low survival rate pose severe tests for emergency and critical care.Although modern CPR techniques significantly improve the immediate resuscitation success rate in CA patients,poor outcomes such as neurological impairment still significantly increase the long-term care burden and reduce the quality of survival.In recent years,the application of remote ischemic conditioning(RIC)has attracted much attention in the field of cardiac arrest through its unique myocardial-nerve dual protection mechanism against the heart.This paper summarizes the conceptual connotation,physiological mechanism,operation method,and its application progress in CA and explores the potential of this technology in the field of CA care in order to provide reference for the research and application of RIC in the field of emergency care. 展开更多
关键词 Remote ischemic conditioning Cardiac arrest NURSING Review
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Development of a Liquid Desiccant Air Conditioning System Using Ionic Liquids
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作者 Hiroshi Nakayama Masatoshi Harada Xinming Wang 《Journal of Civil Engineering and Architecture》 2025年第2期74-81,共8页
LDACs(liquid desiccant air-conditioners)with heat pump can perform cooling dehumidification or heating humidification,and have high energy-saving and sterilization performance.Therefore,they are installed in hospitals... LDACs(liquid desiccant air-conditioners)with heat pump can perform cooling dehumidification or heating humidification,and have high energy-saving and sterilization performance.Therefore,they are installed in hospitals,nursing homes,and food factories,where humidity control is required.However,LiCl(lithium chloride),a conventional humidity control liquid,is highly corrosive to metals,requiring the use of highly corrosion-resistant materials for the pipes and the heat exchangers.These lead to the problem that the manufacturing cost of the air conditioner increases.Therefore,we developed an inexpensive and compact LDAC by adopting a novel IL(ionic liquid)that does not corrode the metals commonly used in air conditioners.In this study,we evaluated the metal solubilities and sterilizing properties of the IL.Based on the physical properties of the IL,the humidity control module was improved for the purpose of downsizing and cost reduction of the unit.Moreover,we conducted a performance evaluation of the LDAC in the environmental test room under the condition in which temperature and humidity change rapidly in short period of time to simulate the condition of sudden showers of rain in summer.Test results showed that processed air was supplied at very stable level. 展开更多
关键词 Liquid desiccant air conditioning ILS heat pump DEHUMIDIFICATION
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Improving the Performance of Thermoelectric Systems for Air Conditioning Using Different Configurations
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作者 Hind Abdulrahman Mahmood Ameer Abed Jaddoa Mohammed K.Al-Saadi 《Frontiers in Heat and Mass Transfer》 2025年第4期1281-1302,共22页
Thermoelectric air conditioning systems based on the Peltier effect had two modes:heating and cooling.In this work,the proposed design provides continuous improvement in COP from the first minute of operation.In cooli... Thermoelectric air conditioning systems based on the Peltier effect had two modes:heating and cooling.In this work,the proposed design provides continuous improvement in COP from the first minute of operation.In cooling mode,the coefficient of performance(COP)was 1.176 due to the techniques used in this device,and it increased to 1.24 in the last minute of operation.Concerning the steady-state scenario,from the first minute,the Qc was larger than the W for the entire duration of the operation.The output temperature reaches 18.97℃ ,and the temperature on the cold side reaches 4.96℃ in the fifteen minutes of operation.The cooling mood was checked in Iraq/Baghdad in October with a temperature of 31℃ .Furthermore,the heating mode was checked in December with a temperature of 22℃ .Due to the size of the component on the cold side being small compared with the size of the component on the heat side,it reached a steady state in 13 min.This means the COP in heating mode reached 1.01 in 14 min.Furthermore,due to the presence of a thermal insulator made inside the device to separate the cold side and the hot side,the difference in temperature causes a noticeable little ascent.This is why the COP increased because it kept the degree differences low.Performance enhancements were achieved by optimizing the behavior of thermoelectric materials.The device contains 3 Peltier elements,a water-cooled system with one Peltier,a heat sink,and a fan.The design of the dehumidification system addresses the humidity issue commonly associated with thermoelectric air conditioners.In this context,the results indicate that the humidity rates had decreased and the cooling rate had increased with these innovative techniques,and thus,excellent performance can be achieved even if the Seebeck coefficient is not at its highest based on the condition of providing the Peltier elements’reliability and optimal thermal performance for various applications requiring both cooling and heating functions.The insulation plays a critical role in maintaining the efficiency of the system,reducing energy consumption,and ensuring long-term functionality.The proposed system is valuable for devices or environments that demand precise and dual thermal control with minimal energy wastage. 展开更多
关键词 Peltier effect Seebeck coefficient COP THERMOELECTRIC air conditioning performance enhancement
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Analysis of Air Conditioning Unit Performance Due to Variations in Water Cooling Temperature Using an Extra Cooling Water Loop
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作者 Noor Moneer Basher Omar Rafae Alomar +1 位作者 Omar Mohammed Ali Diyar Abdullah Ahmed 《Frontiers in Heat and Mass Transfer》 2025年第6期2001-2024,共24页
The energy consumption of a Split air conditioning unit(ACU)inside a building is extremely large,and efforts to decrease this issue are ongoing.The current work aims to experimentally investigate the thermal performan... The energy consumption of a Split air conditioning unit(ACU)inside a building is extremely large,and efforts to decrease this issue are ongoing.The current work aims to experimentally investigate the thermal performance of ACU using an external cooling-water loop for pre-cooling the condenser to improve the efficiency and to reduce energy consumption by reducing refrigerant temperature before entering the condenser,thereby reducing the coefficient of performance.The experiments are performed on ACU with and without using an external cooling-water loop under different climate conditions.By using the experimental data,the systems’performances for both cases are evaluated based on the energy,exergy,and pressure drop analysis.Effects of several parameters,e.g.,ambient temperature,inlet water temperature,and water volume flow rate,on the energy and exergy performances of ACU systems are presented for the purpose of comparison.The outcomes display that the use of an external cooling water loop system has a significant impact on the system performance as compared to conventional ACU.The results display that the addition of an external cooling-water loop leads to a reduction in the compressor power consumption and to an increase in the coefficient of performance(COP)as compared to a normal ACU.The maximum reduction in compressor power consumption is obtained equal 37%at T_(w)=15℃and 11 L/min,whereas the maximum enhancement in COP is obtained equal 21.5%at T_(w)=30℃,11 L/min,and T_(amb)=45℃.The modified model shows an increase in exergy efficiency with the maximum enhancement of about 17%at T_(w)=30℃and 15.8 L/min.The use of an external cooling water loop leads to a reduction in the irreversibility process of the compressor,evaporator and expansion valve and to an increase in the condenser losses.The outcomes show that the pressure drop is reduced by using a cooling water loop as compared to a normal ACU,where the reduction becomes more evident with a reduction in water volume flow rate and inlet temperature.Finally,the present study reveals that the use of an external cooling water loop system leads to an improvement in the performance of ACUs. 展开更多
关键词 Air conditioning unit energy EXERGY water heat exchanger pressure drop pre-cool condenser
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Study on the Impact of Humidity Control Strategy on Energy Saving Effect of Centralized Central Air Conditioning System
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作者 Xiaolian Lin 《Journal of Electronic Research and Application》 2025年第4期303-309,共7页
As an indispensable part of modern buildings,centralized central air conditioning systems play an important role in maintaining the comfort and air quality of the indoor environment.However,with the increasing energy ... As an indispensable part of modern buildings,centralized central air conditioning systems play an important role in maintaining the comfort and air quality of the indoor environment.However,with the increasing energy consumption,how to improve the energy efficiency ratio of air conditioning systems and reduce energy consumption has become an important issue in research and practice.The purpose of this paper is to discuss the impact of humidity control strategies on energy saving in centralized central air conditioning systems,with a view to providing a theoretical basis and practical guidance for realizing building energy efficiency. 展开更多
关键词 Centralized central air conditioning system Energy saving potential Humidity control strategy Energy saving effect assessment
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Research on the Path of Integrating Innovation and Entrepreneurship Education into the Curriculum Ideology and Politics of Refrigeration and Air Conditioning Major in Colleges and Universities
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作者 Tianjiao Zhang Xi Chen +1 位作者 Ni Liu Zhaorui Zhao 《Journal of Contemporary Educational Research》 2025年第9期398-404,共7页
In the background of reform of higher education in the new era,how to organically integrate innovation and entrepreneurship education with curriculum ideology and politics has become a key proposition for deepening th... In the background of reform of higher education in the new era,how to organically integrate innovation and entrepreneurship education with curriculum ideology and politics has become a key proposition for deepening the reform of education and teaching.As an important branch in the field of engineering,the refrigeration and air conditioning major not only undertakes the professional mission of cultivating technical talents in the industry,but also shoulders the era responsibility of implementing the fundamental task of cultivating morality and talents.Combining with the characteristics of the refrigeration and air conditioning major,this paper systematically analyzes the internal logic and practical significance of the integration of innovation and entrepreneurship education and curriculum ideology and politics,and explores its implementation paths in aspects such as the excavation of curriculum content,the innovation of teaching methods,the construction of practical platforms and the optimization of evaluation systems.It aims to provide practical reference and theoretical support for promoting the collaborative education of professional education and ideological and political education. 展开更多
关键词 Innovation and entrepreneurship education Curriculum ideology and politics Refrigeration and air conditioning Education reform
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Investigation on Aerodynamic Interaction of Tandem Tilt⁃Wing and Multi⁃rotor in Transition Condition
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作者 DENG Jinghui YUAN Mingchuan +2 位作者 HUANG Shuilin SUN Huixun ZHANG Zihan 《Transactions of Nanjing University of Aeronautics and Astronautics》 2026年第1期1-14,共14页
The complex aerodynamic interaction between tandem tilt-wing and multi-rotor directly affects the wing surface flow and rotor thrust,making it a critical factor during the tilt transition process of this configuration... The complex aerodynamic interaction between tandem tilt-wing and multi-rotor directly affects the wing surface flow and rotor thrust,making it a critical factor during the tilt transition process of this configuration of rotorcraft.The aerodynamic interaction of tandem tilt-wing and multi-rotor is investigated based on the CFD method.The aerodynamic effect of multi tilt-rotor is simulated as virtual disk modeling by adding source terms to the Navier-Stokes equations,effectively reducing the calculation time while maintaining the accuracy of aerodynamic interaction calculations.Aerodynamic forces and flow field characteristics of the tandem tilt-wing and multi-rotor under different tilt angles are compared between cases with and without aerodynamic interaction.Furthermore,the differences in aerodynamic forces between dynamic tilt transition and fixed-angle conditions were compared.The results show that the aerodynamic interaction of multi-rotor obviously increases the lift of front tilt-wing at different tilt angles,the wing lift under interaction is increased by more than 40%compared with isolated wing at tilt angle of 15°for the computation in this paper,which is related to the increase of wing flow velocity and the suppression of flow separation caused by multi-rotor;the wing blocking effect will increase rotor thrust,especially near the tilt angles of 30°and 45°;the increases of rear wing lift and rear rotor thrust under aerodynamic interaction are not significant because of suppression by the front wing’s downwash;the unsteady effects during dynamic tilting have a relatively minor impact on aerodynamic interaction,with the aerodynamic forces on the rotors and wings during the dynamic tilting process showing little difference from those under corresponding fixed tilt angles. 展开更多
关键词 aerodynamic interaction TANDEM tilt-wing multi tilt-rotors transition condition
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Generating golden Syrian hamsters with conditional alleles via zygote microinjection of CRISPR/Cas9
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作者 Wei Chen Xu Zhang +14 位作者 Rui Fan Xia Li Feifei Guan Gefan Wan Weining Kong Xiaolong Qi Shuo Pan Sijing Shi Yuanlong Su Shan Gao Wei Huang Xunde Xian Jiangning Liu Yuhui Wang Yuanwu Ma 《Animal Models and Experimental Medicine》 2026年第2期308-318,共11页
Background:The golden Syrian hamster is a valuable animal model for studying carcinogenesis,metabolic disorders,cardiovascular diseases,and viral infections due to its biological and pathological similarities to human... Background:The golden Syrian hamster is a valuable animal model for studying carcinogenesis,metabolic disorders,cardiovascular diseases,and viral infections due to its biological and pathological similarities to humans.However,the development of genetically engineered hamsters has lagged behind that of mice and rats,largely because of an embryonic development block at the two-cell stage in vitro.Although CRISPR/Cas9-mediated gene knockout has been achieved in hamsters,precise DNA fragment insertion or conditional knockout(cKO)models have not previously been reported,likely due to technical limitations in embryo manipulation and insufficient efficiency of homology-directed repair(HDR).Methods:In this study,we generated conditional alleles of the ApoF gene in golden Syrian hamsters.A two-cut strategy was applied using Cas9 protein,two sgRNAs,and a single donor plasmid containing exon 2 flanked by loxP sites and two~0.8 kb homology arms.A mixture of Cas9 protein,sgRNAs,and the donor plasmid was microinjected into the pronuclei of one-cell stage hamster embryos.Results:The efficiency of CRISPR/Cas9-mediated loxP knock-in reached up to 27%,and the genetically modified floxed alleles were successfully transmitted through the germline.The functionality of the inserted loxP sites was validated by in vivo Cremediated recombination following local administration of AAV vectors,including AAV-cTnT-Cre in the heart and AAV-CMV-Cre in the brain.Conclusions:To our knowledge,this work represents the first successful establishment of a conditional knockout model in the golden Syrian hamster,providing a valuable tool for mechanistic studies of gene function and disease modeling. 展开更多
关键词 conditional knockout genome editing Golden Syrian hamster
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Existence,Uniqueness and Stability of Bounded Solutions for Minkowski-Curvature Problems with Asymptotic Boundary Conditions
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作者 Tianlan CHEN Xuying TANG 《Journal of Mathematical Research with Applications》 2026年第1期57-70,共14页
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→... In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions. 展开更多
关键词 mean curvature operator UNIQUENESS asymptotic boundary conditions bounded solution
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Evolve and Revoke:A Secure and Efficient Conditional Proxy Re-Encryption Scheme with Ciphertext Evolution
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作者 Han-Yu Lin Tung-Tso Tsai Yi-Jia Ye 《Computers, Materials & Continua》 2026年第4期1565-1583,共19页
Cloud data sharing is an important issue in modern times.To maintain the privacy and confidentiality of data stored in the cloud,encryption is an inevitable process before uploading the data.However,the centralized ma... Cloud data sharing is an important issue in modern times.To maintain the privacy and confidentiality of data stored in the cloud,encryption is an inevitable process before uploading the data.However,the centralized management and transmission latency of the cloud makes it difficult to support real-time processing and distributed access structures.As a result,fog computing and the Internet of Things(IoT)have emerged as crucial applications.Fog-assisted proxy re-encryption is a commonly adopted technique for sharing cloud ciphertexts.It allows a semitrusted proxy to transforma data owner’s ciphertext into another re-encrypted ciphertext intended for a data requester,without compromising any information about the original ciphertext.Yet,the user revocation and cloud ciphertext renewal problems still lack effective and secure mechanisms.Motivated by it,we propose a revocable conditional proxy re-encryption scheme offering ciphertext evolution(R-CPRE-CE).In particular,a periodically updated time key is used to revoke the user’s access privileges while an access condition prevents a malicious proxy from reencrypting unauthorized ciphertext.We also demonstrate that our scheme is provably secure under the notion of indistinguishability against adaptively chosen identity and chosen ciphertext attacks in the random oracle model.Performance analysis shows that our scheme reduces the computation time for a complete data access cycle from an initial query to the final decryption by approximately 47.05%compared to related schemes. 展开更多
关键词 REVOCABLE proxy re-encryption conditional access control ciphertext evolution fog computing
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Dynamic characteristics analysis of rack railway track system under traction conditions by experimental test
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作者 Zhihui Chen Guojun Yang +3 位作者 Zaigang Chen Haitao Zhang Jizhong Yang Wanming Zhai 《Railway Engineering Science》 2026年第1期40-54,共15页
The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from... The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from the rack vehicle in traction conditions,a systematic test of the track subsystem was carried out on a large-slope test line.In the test,the bending stress of the rack teeth,the wheel-rail forces,and the acceleration of crucial components in the track system were measured.Subsequently,a detailed analysis was conducted on the tested signals of the rack railway track system in the time domain and the time-frequency domains.The test results indicate that the traction force significantly affects the rack tooth bending stress and the wheel-rail forces.The vibrations of the track system under the traction conditions are mainly caused by the impacts generated from the gear-rack engagement,which are then transferred to the sleepers,the rails,and the ballast beds.Furthermore,both the maximum stress on the racks and the wheel-rail forces measured on the rails remain below their allowable values.This experimental study evaluates the load characteristics and reveals the vibration characteristics of the rack railway track system under the vehicle’s ultimate load,which is very important for the load-strengthening design of the key components such as racks and the vibration and noise reduction of the track system. 展开更多
关键词 Rack railway Vehicle-track coupled dynamics Traction condition Experimental test Gear-rack engagement
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MODELING OF A MICROPOLAR THIN FILM FLOW WITH RAPIDLY VARYING THICKNESS AND NON-STANDARD BOUNDARY CONDITIONS
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作者 María ANGUIANO Francisco Javier SUÁREZ-GRAU 《Acta Mathematica Scientia》 2026年第1期209-242,共34页
In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary c... In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary conditions on the flat bottom.Assuming“Reynolds roughness regime”,in which the thickness of the domain is very small compared to the wavelength of the roughness(i.e.a very slight roughness),we rigorously derive a generalized Reynolds equation for pressure,clearly showing the roughness-induced effects.Moreover,we give expressions for the average velocity and microrotation. 展开更多
关键词 micropolar fluid thin-film flow rapidly oscillating boundary nonzero boundary conditions HOMOGENIZATION
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In-situ experiment on pre-bored grouted planted geothermal energy piles in winter conditions
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作者 PAN Weijie FANG Pengfei +3 位作者 XIE Xinyu ZHANG Rihong YAO Yanming ZHU Dayong 《地基处理》 2026年第1期13-23,共11页
The main purpose of using geothermal energy piles(GEPs)is to enable the exploitation of geothermal energy for meeting the heating/cooling demands of buildings efficiently.However,the installation process of convention... The main purpose of using geothermal energy piles(GEPs)is to enable the exploitation of geothermal energy for meeting the heating/cooling demands of buildings efficiently.However,the installation process of conventional GEPs is inconvenient compared with that of traditional foundation piles.The pre-bored grouted planted geothermal energy pile(PGP GEP)is an innovative technology to simplify the installation process.Most investigations of in-situ experiments for conventional GEPs have focused on summer conditions.An in-situ test for a PGP GEP was conducted to analyze the temperature changes and thermo-mechanical characteristics under winter conditions.The results show that the average temperature of the pile decreased by 5.1℃,and the pile exhibited a general trend of high temperatures at both ends and low temperatures in the middle.In mechanics,strong pile end restraints resulted in smaller observed axial strain and higher axial thermal-induced force in the pile ends than at the middle of the pile. 展开更多
关键词 pre-bored grouted planted energy pile in-situ test winter conditions thermo-mechanical characteristics
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Gearbox Fault Diagnosis under Varying Operating Conditions through Semi-Supervised Masked Contrastive Learning and Domain Adaptation
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作者 Zhixiang Huang Jun Li 《Computer Modeling in Engineering & Sciences》 2026年第2期448-470,共23页
To address the issue of scarce labeled samples and operational condition variations that degrade the accuracy of fault diagnosis models in variable-condition gearbox fault diagnosis,this paper proposes a semi-supervis... To address the issue of scarce labeled samples and operational condition variations that degrade the accuracy of fault diagnosis models in variable-condition gearbox fault diagnosis,this paper proposes a semi-supervised masked contrastive learning and domain adaptation(SSMCL-DA)method for gearbox fault diagnosis under variable conditions.Initially,during the unsupervised pre-training phase,a dual signal augmentation strategy is devised,which simultaneously applies random masking in the time domain and random scaling in the frequency domain to unlabeled samples,thereby constructing more challenging positive sample pairs to guide the encoder in learning intrinsic features robust to condition variations.Subsequently,a ConvNeXt-Transformer hybrid architecture is employed,integrating the superior local detail modeling capacity of ConvNeXt with the robust global perception capability of Transformer to enhance feature extraction in complex scenarios.Thereafter,a contrastive learning model is constructed with the optimization objective of maximizing feature similarity across different masked instances of the same sample,enabling the extraction of consistent features from multiple masked perspectives and reducing reliance on labeled data.In the final supervised fine-tuning phase,a multi-scale attention mechanism is incorporated for feature rectification,and a domain adaptation module combining Local Maximum Mean Discrepancy(LMMD)with adversarial learning is proposed.This module embodies a dual mechanism:LMMD facilitates fine-grained class-conditional alignment,compelling features of identical fault classes to converge across varying conditions,while the domain discriminator utilizes adversarial training to guide the feature extractor toward learning domain-invariant features.Working in concert,they markedly diminish feature distribution discrepancies induced by changes in load,rotational speed,and other factors,thereby boosting the model’s adaptability to cross-condition scenarios.Experimental evaluations on the WT planetary gearbox dataset and the Case Western Reserve University(CWRU)bearing dataset demonstrate that the SSMCL-DA model effectively identifies multiple fault classes in gearboxes,with diagnostic performance substantially surpassing that of conventional methods.Under cross-condition scenarios,the model attains fault diagnosis accuracies of 99.21%for the WT planetary gearbox and 99.86%for the bearings,respectively.Furthermore,the model exhibits stable generalization capability in cross-device settings. 展开更多
关键词 GEARBOX variable working conditions fault diagnosis semi-supervised masked contrastive learning domain adaptation
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Conditional Generative Adversarial Network-Based Travel Route Recommendation
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作者 Sunbin Shin Luong Vuong Nguyen +3 位作者 Grzegorz J.Nalepa Paulo Novais Xuan Hau Pham Jason J.Jung 《Computers, Materials & Continua》 2026年第1期1178-1217,共40页
Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of... Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of user preferences.To address this,we propose a Conditional Generative Adversarial Network(CGAN)that generates diverse and highly relevant itineraries.Our approach begins by constructing a conditional vector that encapsulates a user’s profile.This vector uniquely fuses embeddings from a Heterogeneous Information Network(HIN)to model complex user-place-route relationships,a Recurrent Neural Network(RNN)to capture sequential path dynamics,and Neural Collaborative Filtering(NCF)to incorporate collaborative signals from the wider user base.This comprehensive condition,further enhanced with features representing user interaction confidence and uncertainty,steers a CGAN stabilized by spectral normalization to generate high-fidelity latent route representations,effectively mitigating the data sparsity problem.Recommendations are then formulated using an Anchor-and-Expand algorithm,which selects relevant starting Points of Interest(POI)based on user history,then expands routes through latent similarity matching and geographic coherence optimization,culminating in Traveling Salesman Problem(TSP)-based route optimization for practical travel distances.Experiments on a real-world check-in dataset validate our model’s unique generative capability,achieving F1 scores ranging from 0.163 to 0.305,and near-zero pairs−F1 scores between 0.002 and 0.022.These results confirm the model’s success in generating novel travel routes by recommending new locations and sequences rather than replicating users’past itineraries.This work provides a robust solution for personalized travel planning,capable of generating novel and compelling routes for both new and existing users by learning from collective travel intelligence. 展开更多
关键词 Travel route recommendation conditional generative adversarial network heterogeneous information network anchor-and-expand algorithm
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RNPC-net:Automatic recognition and mapping of weathering degree and groundwater condition of tunnel faces
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作者 Xiang Wu Fengyan Wang +4 位作者 Jianping Chen Mingchang Wang Lina Cheng Chengyao Zhang Junke Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1138-1159,共22页
Accurate and rapid recognition of weathering degree(WD)and groundwater condition(GC)is essential for evaluating rock mass quality and conducting stability analyses in underground engineering.Conventional WD and GC rec... Accurate and rapid recognition of weathering degree(WD)and groundwater condition(GC)is essential for evaluating rock mass quality and conducting stability analyses in underground engineering.Conventional WD and GC recognition methods often rely on subjective evaluation by field experts,supplemented by field sampling and laboratory testing.These methods are frequently complex and timeconsuming,making it challenging to meet the rapidly evolving demands of underground engineering.Therefore,this study proposes a rock non-geometric parameter classification network(RNPC-net)to rapidly achieve the recognition and mapping ofWD and GC of tunnel faces.The hybrid feature extraction module(HFEM)in RNPC-net can fully extract,fuse,and utilize multi-scale features of images,enhancing the network's classification performance.Moreover,the designed adaptive weighting auxiliary classifier(AC)helps the network learn features more efficiently.Experimental results show that RNPC-net achieved classification accuracies of 0.8756 and 0.8710 for WD and GC,respectively,representing an improvement of approximately 2%e10%compared to other methods.Both quantitative and qualitative experiments confirm the effectiveness and superiority of RNPC-net.Furthermore,for WD and GC mapping,RNPC-net outperformed other methods by achieving the highest mean intersection over union(mIOU)across most tunnel faces.The mapping results closely align with measurements provided by field experts.The application of WD and GC mapping results to the rock mass rating(RMR)system achieved a transition from conventional qualitative to quantitative evaluation.This advancement enables more accurate and reliable rock mass quality evaluations,particularly under critical conditions of RMR. 展开更多
关键词 Tunnel face Weathering degree Groundwater condition RNPC-net Hybrid feature extraction module Recognition and mapping
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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3D culture model drug screening
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