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Design and Verification of an Auxiliary System for High Vacuum Die Casting 被引量:3
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作者 GE Xiaohong HUANG Hongwu +1 位作者 LI Hui LIU Yadan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第5期547-552,共6页
Vacuum die casting is the optimal method to produce high quality aluminum alloy components.At present,there are still very few systematic studies on vacuum die casting theory and equipment design.On the basis of the e... Vacuum die casting is the optimal method to produce high quality aluminum alloy components.At present,there are still very few systematic studies on vacuum die casting theory and equipment design.On the basis of the existing theories of the vacuum die casting pumping and venting systems,a simplified model is established in this research.The model has an aggregate unit consisted of "vacuum pump + buffer tank" and a cylindrical container(including the shot sleeve,cavity and exhaust channel).The theoretical analysis is carried out between the cavity pressure and the pumping time under different volume models.An auxiliary system for high vacuum die casting is designed based on the above analysis.This system is composed of a vacuum control machine and a new vacuum stop valve.The machine has a human-computer control mode with "programmable logic controller(PLC) + touch screen" and a real-time monitoring function of vacuum degree for buffer tank and die cavity.The vacuum stop valve with the "compressed gas + piston rod + labyrinth groove" structure can realize the function of whole-process vacuum venting.The new system shows great advantages on vacuuming the cavity with a much faster speed by making tests on an existing die casting mold and a 250 t die casting machine.A die cavity pressure less than 10 kPa can be reached within 0.8 s in the experiment and the porosity of castings can be greatly decreased.The systematic studies on vacuum die casting theory and equipment have a great guiding significance for high vacuum die casting,and can also be applied to other high vacuum forming in related theoretical and practical research. 展开更多
关键词 vacuum die casting pumping model high vacuum vacuum stop valve auxiliary system
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Entanglement Capacity of Two-Qubit Unitary Operator with the Help of Auxiliary System 被引量:2
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作者 HU Bao-Lin DI Yao-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1029-1032,共4页
The'entanglement capacity of general two-qubit unitary operators is studied when auxiliary systems are allowed, and the analytical results based on linear entropy when input states are disentangled are given. From th... The'entanglement capacity of general two-qubit unitary operators is studied when auxiliary systems are allowed, and the analytical results based on linear entropy when input states are disentangled are given. From the results the condition for perfect entangler, α1 = α2 = π/4, is obtained. Contrary to the case without auxiliary system, the parameter α3 may play active role to the entanglement capacity when auxiliary systems are allowed. 展开更多
关键词 unitary operator entanglement capacity linear entropy auxiliary system
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Analysis on the rules of prescriptions for ischemic stroke based on the traditional Chinese medicine inheritance auxiliary system
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作者 Jing-Na Zhou Zi-Qi Jing +1 位作者 Xin-Zhe Zhao Guo-Wei Zhang 《Drug Combination Therapy》 2019年第2期65-74,共10页
In China,traditional Chinese medicine is widely used in the treatment of ischemic stroke,but its prescription rules needs to be further studied.This paper uses the traditional Chinese medicine inheritance auxiliary sy... In China,traditional Chinese medicine is widely used in the treatment of ischemic stroke,but its prescription rules needs to be further studied.This paper uses the traditional Chinese medicine inheritance auxiliary system(a software)to analyze the composition rules of a large number of prescriptions for the treatment of ischemic stroke,and discusses the clinical rationality of the new prescriptions.We found that the prescriptions for the treatment of ischemic stroke are mainly composed by herbs for promoting blood circulation and removing blood stasis,dredging collaterals and tonifying deficiency,and some of the new prescriptions are also in line with this characteristic.This paper can provide reference for clinical prescription in the treatment of ischemic stroke and the development of related new drugs. 展开更多
关键词 Ischemic stroke Traditional Chinese medicine INHERITANCE auxiliary system Prescription rule Promoting BLOOD circulation and removing BLOOD STASIS
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Geological Hazard Risk Evaluation Auxiliary System
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《地理空间信息》 2015年第4期I0001-I0006,共6页
This paper analyzed the process and technologies of geological hazard risk evaluation at first, and then explored a set of geological hazard risk evaluation auxiliary software system, including field investigation, th... This paper analyzed the process and technologies of geological hazard risk evaluation at first, and then explored a set of geological hazard risk evaluation auxiliary software system, including field investigation, the present situation in different stages of the evaluation, prediction evaluation and comprehensive evaluation. This system set the field line drawing, delimit, red plane projection of evaluation area slope stability analysis, comprehensive partition and so on four kind of model for the integration. Starting from the feasibility, practicability and extensibility of system, the paper established the system architecture style, data modeling and standard, and discussed four kinds of models in the system. 展开更多
关键词 GEOLOGICAL hazard evaluation auxiliary system GIS
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The Intelligent Terminal Design for Integrated Substation Auxiliary System
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作者 Enliang Pang Sanfeng Zhang Yi Ji 《Journal of Software Engineering and Applications》 2013年第5期11-15,共5页
The integrated substation auxiliary system is a project composed by software and hardware to help operators of a substation carry daily maintain works. The intelligent terminal is the key part of the system and it pro... The integrated substation auxiliary system is a project composed by software and hardware to help operators of a substation carry daily maintain works. The intelligent terminal is the key part of the system and it provides important UI and communication functions for the user. Smart phones can achieve higher bandwidth data communication, and at the same time can carry Bluetooth communication, video call, multimedia display and other functions. Smart phone is a potential common platform, suitable for the deployment of substation integrated auxiliary system terminal. Based on the Android Smart phone platform, this paper develops intelligent client-side software for the integrated substation auxiliary system and it can realize the operation ticket control, the video call, the substation map display and other functions. This client-side software has been applied in practice, and has gained good effects. 展开更多
关键词 INTEGRATED SUBSTATION auxiliary system Android INTELLIGENT TERMINAL SUBSTATION
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Multi-mode energy management strategy for hydraulic hub-motor auxiliary system based on improved global optimization algorithm 被引量:2
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作者 ZENG XiaoHua WU ZiQiao +2 位作者 WANG Yue SONG DaFeng LI GuangHan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2020年第10期2082-2097,共16页
Heavy commercial vehicles equipped with a hydraulic hub-motor auxiliary system(HHMAS)often operate under complex road conditions.Selecting appropriate operating mode and realizing reasonable energy management to match... Heavy commercial vehicles equipped with a hydraulic hub-motor auxiliary system(HHMAS)often operate under complex road conditions.Selecting appropriate operating mode and realizing reasonable energy management to match unpredictable road conditions are the keys to the driving performance and fuel economy of HHMAS.Therefore,a multi-mode energy management strategy(MM-EMS)based on improved global optimization algorithm is proposed in this study for HHMAS.First,an improved dynamic programming(DP)algorithm for HHMAS is developed.This improved DP algorithm considers the effect of SOC and vehicle speed,thereby preventing the calculation results from falling into local optimization.This algorithm also reduces the dimension of the control variable data grid,and the calculation time is reduced by 35%without affecting the accuracy.Second,a MM-EMS with hierarchical control is proposed.This strategy extracts the optimal control rules from the results of the improved DP algorithm.Then it divides the system’s operating region into two types,namely,single-mode working region and mixedmode working region.In the single-mode working region,mode switching is realized through fixed thresholds.In the mixedmode working region,a linear quadratic regulator(LQR)is adopted to determine a target mode and realize SOC tracking control.Finally,the designed MM-EMS is verified separately in offline simulation and hardware-in-the-loop(HIL)under actual vehicle test cycles.Simulation results show that the results between HIL and offline simulation are largely coincidence.Besides,in comparison with the engine optimal control strategy,the designed MM-EMS can achieve an approximate optimal control,with oil savings of 3.96%. 展开更多
关键词 hydraulic hub-motor auxiliary system energy management strategy global optimization hierarchical control
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Saturation-tolerant prescribed control of MIMO nonlinear systems with actuator faults
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作者 Hao Lei Ruihang Ji +1 位作者 Dongyu Li Shuzhi Sam Ge 《Journal of Automation and Intelligence》 2025年第1期10-20,共11页
This paper addresses the tracking control problem of a class of multiple-input–multiple-output nonlinear systems subject to actuator faults.Achieving a balance between input saturation and performance constraints,rat... This paper addresses the tracking control problem of a class of multiple-input–multiple-output nonlinear systems subject to actuator faults.Achieving a balance between input saturation and performance constraints,rather than conducting isolated analyses,especially in the presence of frequently encountered unknown actuator faults,becomes an interesting yet challenging problem.First,to enhance the tracking performance,Tunnel Prescribed Performance(TPP)is proposed to provide narrow tunnel-shape constraints instead of the common over-relaxed trumpet-shape performance constraints.A pair of non-negative signals produced by an auxiliary system is then integrated into TPP,resulting in Saturation-tolerant Prescribed Performance(SPP)with flexible performance boundaries that account for input saturation situations.Namely,SPP can appropriately relax TPP when needed and decrease the conservatism of control design.With the help of SPP,our developed Saturation-tolerant Prescribed Control(SPC)guarantees finite-time convergence while satisfying both input saturation and performance constraints,even under serious actuator faults.Simulations are conducted to illustrate the effectiveness of the proposed SPC. 展开更多
关键词 Prescribed performance control Input saturation auxiliary system Actuator faults MIMO nonlinear systems Finite-time stability
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Parameter estimation for multirate multi-input systems using auxiliary model and multi-innovation 被引量:3
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作者 Lili Han Feng Ding 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1079-1083,共5页
The multirate multi-input systems have different updating periods and sampling periods such that the conventional identification algorithms cannot be used to identify such multirate systems. By using the auxiliary mod... The multirate multi-input systems have different updating periods and sampling periods such that the conventional identification algorithms cannot be used to identify such multirate systems. By using the auxiliary model identification idea, the multiinnovation stochastic gradient algorithm is developed to estimate the parameters of multirate systems. Finally, an illustrative example is given to verify the effectiveness of the proposed algorithm. 展开更多
关键词 parameter estimation multirate systems multiinnovation auxiliary model.
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Mining a coal seam below a heating goaf with a force auxiliary ventilation system at Longhua underground coal mine, China 被引量:3
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作者 Wang Gang Xie Jun +1 位作者 Xue Sheng Wang Haiyang 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第1期67-72,共6页
Extraction of a coal seam which lies not far below a heating goafcan be a major safety challenge. A force auxiliary ventilation system was adopted as a control method in successful extraction and recovery of the panel... Extraction of a coal seam which lies not far below a heating goafcan be a major safety challenge. A force auxiliary ventilation system was adopted as a control method in successful extraction and recovery of the panel 30110 of the #3-1 coal seam, which is about 30-40 rn below the heating goaf of the #2-2 seam at Longhua underground coal mine, Shanxi Province, China. Booster fans and ventilation control devices such as doors and regulators were used in the system. The results show that, provided that a force auxiliary ventilation system is properly designed to achieve a pressure balance between a panel and its overlying goat', the system can be used to extract a coal seam overlain by a heating goal. This paper describes the design, installation and performance of the ventilation system during the extraction and recovery phases of the oanel 30110. 展开更多
关键词 Force auxiliary ventilation systemMining under a heating goafMultiple seams of close spacingPressure balance
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Fano interference and transparency in a waveguide-nanocavity hybrid system with an auxiliary cavity
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作者 Yu-Xin Shu Xiao-San Ma +2 位作者 Xian-Shan Huang Mu-Tian Cheng Jun-Bo Han 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期318-322,共5页
We investigate theoretically single photon transport in one-dimensional waveguide coupled to a pair of cavities,which are denoted by the first cavity and the auxiliary cavity.Two cases with no atom and one atom embedd... We investigate theoretically single photon transport in one-dimensional waveguide coupled to a pair of cavities,which are denoted by the first cavity and the auxiliary cavity.Two cases with no atom and one atom embedded in the first cavity are discussed.The Fano dips in the transmission spectrum and locations of transparency window are calculated.When no atom is embedded in the first cavity,there exists a transparency window under the condition that the first cavity and the auxiliary cavity are not resonant.The locations of the transparency window and Fano line type depend strongly on the eigen frequency of the auxiliary cavity and the coupling strength between the auxiliary cavity and the waveguide.When one atom is embedded in the first cavity,we show that the transparency window exists even though the first cavity,the atom and the auxiliary cavity are resonant.The Fano line type is strongly dependent on the eigen frequency of the auxiliary cavity and the coupling strength.Our results have potential applications in design of quantum devices at the level of single photon,such as single photon switch and single photon routers. 展开更多
关键词 Fano interference waveguide quantum electrodynamics auxiliary cavity
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Auxiliary principle and approximation solvability for system of new generalized mixed equilibrium problems in reflexive Banach spaces
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期231-240,共10页
A new system of generalized mixed equilibrium problems (SGMEPs) involving generalized mixed variational-like inequality problems is introduced and studied in reflexive Banach spaces. A system of auxiliary generalize... A new system of generalized mixed equilibrium problems (SGMEPs) involving generalized mixed variational-like inequality problems is introduced and studied in reflexive Banach spaces. A system of auxiliary generalized mixed equilibrium problems (SAGMEPs) for solving the SGMEPs is first introduced. Existence and uniqueness of the solutions to the SAGMEPs is proved under quite mild assumptions without any coercive conditions in reflexive Banach spaces. Using the auxiliary principle technique, a new iterative algorithm for solving the SGMEPs is proposed and analyzed. Strong convergence of the iterative sequences generated by the algorithm is also proved under quite mild assumptions without any coercive conditions. These results improve, unify, and generalize some recent results in this field. 展开更多
关键词 system of generalized mixed equilibrium problem auxiliary principle iterative algorithm reflexive Banach space
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Auxiliary Model Based Multi-innovation Stochastic Gradient Identification Methods for Hammerstein Output-Error System
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作者 冯启亮 贾立 李峰 《Journal of Donghua University(English Edition)》 EI CAS 2017年第1期53-59,共7页
Special input signals identification method based on the auxiliary model based multi-innovation stochastic gradient algorithm for Hammerstein output-error system was proposed.The special input signals were used to rea... Special input signals identification method based on the auxiliary model based multi-innovation stochastic gradient algorithm for Hammerstein output-error system was proposed.The special input signals were used to realize the identification and separation of the Hammerstein model.As a result,the identification of the dynamic linear part can be separated from the static nonlinear elements without any redundant adjustable parameters.The auxiliary model based multi-innovation stochastic gradient algorithm was applied to identifying the serial link parameters of the Hammerstein model.The auxiliary model based multi-innovation stochastic gradient algorithm can avoid the influence of noise and improve the identification accuracy by changing the innovation length.The simulation results show the efficiency of the proposed method. 展开更多
关键词 Hammerstein output-error system special input signals auxiliary model based multi-innovation stochastic gradient algorithm innovation length
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Research on the Relationship Between Dynamic Behavior of Active Magnetic Bearing System And the Performance of the Auxiliary Bearing
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作者 Zhe Sun Guo-jun Yang +2 位作者 Jing-jing Zhao Xun-shi Yan Zhen-gang Shi 《风机技术》 2021年第4期67-74,共8页
Auxiliary bearings(ABs)are important backup and safety components in active magnetic bearing(AMB)systems.The performance of ABs significantly affects the reliability,safety,and serviceability of theAMB system and the ... Auxiliary bearings(ABs)are important backup and safety components in active magnetic bearing(AMB)systems.The performance of ABs significantly affects the reliability,safety,and serviceability of theAMB system and the rotating equipment.Research on the dynamic behavior during the touchdown process is crucial for analyzing the severity of the touchdown and the behavior is closely related to the performance of theAB.In this paper,a friction torque coefficient is introduced to evaluate the performance ofAB and the touchdown process is simulated and evaluated with various values of this coefficient with a detailed rotor-AB model of a verticalAMB system.The results show that large friction torque coefficient will result in undesired backward whirl of the rotor and catastrophic large load on the AB.Based on these results,this paper suggests that large friction torque coefficient ofABshould be avoided in practice. 展开更多
关键词 Active Magnetic Bearing system auxiliary Bearing Rotor Touchdown Dynamic Behavior Friction Torque Coefficient
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Analysis of Application of Multi-system Integrated Auxiliary Control System in Substation
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作者 WANGYanbo 《外文科技期刊数据库(文摘版)工程技术》 2022年第9期034-038,共5页
With the rapid development of computer technology and network communication technology, the automation construction of power system is becoming more and more perfect, especially in the intelligent auxiliary control sy... With the rapid development of computer technology and network communication technology, the automation construction of power system is becoming more and more perfect, especially in the intelligent auxiliary control system of substation. The latest computer technology, network communication technology and sensor detection technology are widely used, and video monitoring system, fire alarm, entrance guard control system, intrusion alarm system, SF6 gas detection system and so on are set up in the safety information management area of substation. For places like substations, the real-time, remote, automatic and unified auxiliary control system is a necessary prerequisite for the safe operation of substations. The independence of each system not only increases the investment cost, but also has many disadvantages in terms of security and real-time. In order to improve the safe, stable and efficient operation of power systems, reduce the investment cost and meet the needs of the development of few people or unattended substations, the application exploration and development of multi-system integration auxiliary control system has become the focus of attention. In this paper, the application of multi-system integrated auxiliary control system in substation is deeply analyzed. 展开更多
关键词 auxiliary control system fusion APPLICATION ALARM LINKAGE
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The Ideale section at Montalbano Jonico (southern Italy): a Standard Auxiliary Boundary Stratotype (SABS) for the Middle Pleistocene Subseries of the Quaternary System
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作者 Maria Marino Patrizia Maiorano +11 位作者 Angela Girone Salvatore Gallicchio Franck Bassinot Sebastien Nomade Quentin Simon Adele Bertini Timothy Herbert Paola Petrosino Marina Addante Rafael La Perna Samanta Trotta Neri Ciaranfi 《Episodes》 2024年第1期121-146,共26页
The Ideale section(IS)at Montalbano Jonico,Italy,has been approved as a Standard Auxiliary Boundary Stratotype(SABS)for the Global boundary Stratotype Section and Point(GSSP)of the Middle Pleistocene Subseries/Subepoc... The Ideale section(IS)at Montalbano Jonico,Italy,has been approved as a Standard Auxiliary Boundary Stratotype(SABS)for the Global boundary Stratotype Section and Point(GSSP)of the Middle Pleistocene Subseries/Subepoch and Chibanian Stage/Age at the Chiba section,Japan.The proposal was submitted to the voting members of the International Commission on Stratigraphy’s Subcommission on Quaternary Stratigraphy(SQS)on May 4,2023,and following discussions was approved on July 8,2023.The 74 m thick IS continuously spans the Marine Isotope Stage(MIS)20–18 interval,and is part of the longer Montalbano Jonico succession(Basilicata,southern Italy in the Mediterranean region)encompassing MIS 37 to early MIS 16.The IS provides a detailed record based on multiple chronologically well constrained marine and terrestrial proxies,which are particularly useful for outlining the paleoclimatic evolution through the Lower–Middle Pleistocene transition.The high-resolution carbon and oxygen isotope stratigraphy outlines glacial–interglacial and stadial–interstadial phases as well as the sub-millennialscale features of Termination IX and the onset of MIS 19c.The sapropel layer equivalent to insolation cycle 74(784 ka)occurs in early MIS 19c.A prominent peak in the 10Be/9Be record at the MIS 19c–19b transition identifies the low geomagnetic dipole moment associated with the Matuyama–Brunhes boundary interval.Two tephra layers(V3 and V4)relevant to boundary interval are 40Ar/39Ar dated.The V4 layer,occurring at the MIS 19c–b transition and in the middle of the 10Be/9Be peak,has an age of 774.1±0.9 ka,corresponding to the age of the Middle Pleistocene GSSP.A high-resolution alkenone sea-surface temperature and several paleobiological records complement the rich chronological and paleoenvironmental dataset from MIS 20 to the inception of MIS 18.The GSSP boundary interval in the IS is represented from 35.50 to 39.50 m,which corresponds to the interval of the highest values of the 10Be/9Be ratio(~776.35–771.87 ka)and includes the V4 tephra layer and the MIS 19c–MIS 19b transition.This SABS extends the correlation potential of the Middle Pleistocene Subseries/Subepoch GSSP interval to the Mediterranean region. 展开更多
关键词 Ideale Section global boundary stratotype section point gssp Chibanian Stage Standard auxiliary Boundary Stratotype standard auxiliary boundary stratotype sabs commission stratigraphy s quaternary stratigraphy sqs Middle Pleistocene Subseries
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Auxiliary Software for Defining the Parameters of the Structural Organization of a Complex System
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作者 Branislav M. Savic 《Journal of Software Engineering and Applications》 2024年第2期109-128,共20页
The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the pro... The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity. 展开更多
关键词 Complex system Structural Organization auxiliary Software PARAMETERS
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Exploration on 6kV Phase II and III Auxiliary Power System Liaison Application
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作者 SUN Jianguo YU Jinwei +1 位作者 KUANG Liu DONG Yalin 《外文科技期刊数据库(文摘版)工程技术》 2021年第12期316-321,共9页
The phase I unit of power plant was shut down, thus the public system operation unit in the plant is used for power supply. The modified technique greatly increased the power consumption of public system. The 330MW co... The phase I unit of power plant was shut down, thus the public system operation unit in the plant is used for power supply. The modified technique greatly increased the power consumption of public system. The 330MW coal-fired unit has no competitive advantage, but the whole plant is forced to conduct single-machine operation because of social responsibility of heating and sludge mixing. The single-machine operation of power plant leads to a large off-grid power settlement amount, and it is impossible to carry out normal starting transformers maintenance, which influences the safety and business benefits of power plant. In this paper, the technique perfection of 6kV phase II and III auxiliary power system liaison is proposed to improve the flexibility of auxiliary power system and realize the mutual backup of two starting transformers, which greatly reduce the off-grid settlement power. Meanwhile, it can give full play to the role of energy storage assisted AGC frequency modulation system and improve the stability of power grid. After demonstration and practical operation test, the safety and economy are obviously improved. 展开更多
关键词 6kV public auxiliary power liaison off-grid power settlement amount energy storage assisted AGC FM
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Structure variation of cadmium naphthalene⁃diphosphonates with the changing rigidity of N⁃donor auxiliary ligands
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作者 XU Yan LI Suzhi +3 位作者 LI Yan FENG Lushun SUN Wentao LI Xinxing 《无机化学学报》 北大核心 2025年第2期395-406,共12页
Five cadmium naphthalene-diphosphonates,formulated as[Cd_(1.5)(1,4-ndpaH_(2))2(4,4'-bpyH)(4,4'-bpy)0.5(H_(2)O)_(2)]2(1),[Cd(1,4-ndpaH_(2))(1,4-bib)0.5(H_(2)O)](2),[Cd(1,4-ndpaH3)2(1,2-dpe)(H_(2)O)]·(1,2-d... Five cadmium naphthalene-diphosphonates,formulated as[Cd_(1.5)(1,4-ndpaH_(2))2(4,4'-bpyH)(4,4'-bpy)0.5(H_(2)O)_(2)]2(1),[Cd(1,4-ndpaH_(2))(1,4-bib)0.5(H_(2)O)](2),[Cd(1,4-ndpaH3)2(1,2-dpe)(H_(2)O)]·(1,2-dpe)·7H_(2)O(3),(1,2-bixH)[Cd3(1,4-ndpaH)(1,4-ndpaH_(2))2(H_(2)O)_(2)](4),and[Cd(1,4-ndpaH_(2))(H_(2)O)]·H_(2)O(5),have been synthesized from the selfassembly reactions of 1,4-naphthalenediphosphonic acid(1,4-ndpaH4)with Cd(NO3)2·4H_(2)O by introducing auxiliary ligands with variation of rigidity,such as 4,4'-bipyridine(4,4'-bpy),1,4-bis(1-imidazolyl)benzene(1,4-bib),1,2-di(4-pyridyl)ethylene(1,2-dpe),1,3-di(4-pyridyl)propane(1,3-dpp),and bis(imidazol-1-ylmethyl)benzene(1,2-bix),respectively.Structure resolution by single-crystal X-ray diffraction reveals that compound 1 possesses a layered framework,in which the{Cd3(PO2)2}trimers made up of corner-sharing two{CdO4N2}and one{CdO6}octahedra are connected by phosphonate groups,forming a ribbon,which are cross-linked by 4,4'-bipy ligands,forming a 2D layer.Compound 2 shows a 3D open-framework structure,where chains of corner-sharing{CdO4N}trigonal bipyramids and{PO3C}tetrahedra are cross-linked by 1,4-bib and/or phosphonate groups.A 1D ladder-like chain structure is found in compound 3,where the ladder-like chains made up of corner-sharing{CdO5N}octahedra and{PO3C}tetra hedra are connected by 1,4-ndpaH_(2)^(2-).Both compounds 4 and 5 obtained by the introduction of flexible ligands during the synthesis show a 2D layered structure,which is formed by ligand crosslinking double metal chains.Interestingly,In 4,flexible 1,2-bix was singly protonated,as vip molecules,filled between layer and layer,while flexible ligand 1,3-dpp is absent in 5.Photophysical measurements indicate that compounds 1-5 show ligand-centered emissions. 展开更多
关键词 naphthalene diphosphate N-donor auxiliary ligands crystal structure RIGIDITY flexibility
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Study the effect of using a dual rotor system on the performance of horizontal axis wind turbines using CFD
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作者 Amr Mokhtar Mahmoud Fouad +1 位作者 Mohamed Rashed Mostafa Mokhtar 《Global Energy Interconnection》 2025年第3期497-509,共13页
This research aims to improve the power output of a horizontal axis wind turbine(HAWT)by using an auxiliary rotor in front of the main rotor,this configuration is called a dual-rotor wind turbine(DRWT).The three-blade... This research aims to improve the power output of a horizontal axis wind turbine(HAWT)by using an auxiliary rotor in front of the main rotor,this configuration is called a dual-rotor wind turbine(DRWT).The three-bladed main rotor has a diameter of 0.9 m and both rotors with NREL S826 airfoil.ANSYS Fluent CFD simulation was used to optimize the DRWT performance where the numerical model was solved using the Realizable k-εt urbulence model.Four parameters are used,diameter ratio between the auxiliary front rotor and the main rear rotor(D_(R)=0.25,D_(R)=0.5,and D_(R)=0.75),axial free stream velocity according to the normal wind speed range in Egypt(V_(o)=5 m/s,V_o=7.5 m/s,and V_(o)=10 m/s),tip speed ratio which ranges from 2 to 8,and the number of blades of the front rotor(B=2,B=3 and B=4).The results show that increasing the number of blades positively impacts performance but at lower tip speed ratios.Smaller diameter ratios yield better performance,while increasing wind speed results in higher power.The best performance was achieved at freestream velocity V_(o)=10 m/s,diameter ratio D_(R)=0.25,front rotor number of blades B=4,and tip speed ratioλ=5 in which the overall maximum power coefficient Cp max=0.552 with an increase with 36.75%compared to the single rotor case. 展开更多
关键词 DUAL-ROTOR Power Freestream PERFORMANCE TURBINE auxiliary Diameter ratio
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Recent Progress in the Auxiliary Phase Enhanced Flexible Piezocomposites
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作者 Xin Gao Mupeng Zheng +5 位作者 Boyue Hou Junshu Wu Mankang Zhu Yunfan Zhang Ke Wang Bing Han 《Energy & Environmental Materials》 2025年第1期292-312,共21页
Piezocomposites with both flexibility and electromechanical conversion characteristics have been widely applied in various fields,including sensors,energy harvesting,catalysis,and biomedical treatment.In the compositi... Piezocomposites with both flexibility and electromechanical conversion characteristics have been widely applied in various fields,including sensors,energy harvesting,catalysis,and biomedical treatment.In the composition of piezocomposites or their preparation process,a category of materials is commonly employed that do not possess piezoelectric properties themselves but play a crucial role in performance enhancement.In this review,the concept of auxiliary phase is first proposed to define these materials,aiming to provide a new perspective for designing high-performance piezocomposites.Three different categories of modulation forms of auxiliary phase in piezocomposites are systematically summarized,including the modification of piezo-matrix,the modification of piezo-fillers,and the construction of special structures.Each category emphasizes the role of the auxiliary phase and systematically discusses the latest advancements and the physical mechanisms of the auxiliary phase enhanced flexible piezocomposites.Finally,a summary and future outlook of piezocomposites based on the auxiliary phase are provided. 展开更多
关键词 auxiliary phase FLEXIBILITY microstructure PIEZOCOMPOSITES PIEZOELECTRICITY
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