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A GENERALIZED SCALAR AUXILIARY VARIABLE METHOD FOR THE TIME-DEPENDENT GINZBURG-LANDAU EQUATIONS
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作者 司智勇 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期650-670,共21页
This paper develops a generalized scalar auxiliary variable(SAV)method for the time-dependent Ginzburg-Landau equations.The backward Euler method is used for discretizing the temporal derivative of the time-dependent ... This paper develops a generalized scalar auxiliary variable(SAV)method for the time-dependent Ginzburg-Landau equations.The backward Euler method is used for discretizing the temporal derivative of the time-dependent Ginzburg-Landau equations.In this method,the system is decoupled and linearized to avoid solving the non-linear equation at each step.The theoretical analysis proves that the generalized SAV method can preserve the maximum bound principle and energy stability,and this is confirmed by the numerical result,and also shows that the numerical algorithm is stable. 展开更多
关键词 time-dependent Ginzburg-Landau equation generalized scalar auxiliary variable algorithm maximum bound principle energy stability
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Research on uninterruptable power supply technology for auxiliary winding of electric locomotive while passing the neutral section
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作者 Yuliang Du 《Railway Sciences》 2024年第2期128-142,共15页
Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of t... Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters.Powered by DC-link voltage of traction converters,the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking.Meanwhile,powered by traction transformers,the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.Design/methodology/approach–Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied.Failure reasons why previous solutions cannot be realized are analyzed.An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper.The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive.This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.Findings–This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid.Control objectives of uninterrupted power supply technology are proposed,which are no overvoltage,no overcurrent and uninterrupted power supply.Originality/value–The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section.Furthermore,this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware. 展开更多
关键词 Electric locomotive auxiliary system Neutral section Uninterruptable power supply OVERVOLTAGE Inrush current
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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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Evolutionary Multitasking With Global and Local Auxiliary Tasks for Constrained Multi-Objective Optimization
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作者 Kangjia Qiao Jing Liang +3 位作者 Zhongyao Liu Kunjie Yu Caitong Yue Boyang Qu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第10期1951-1964,共14页
Constrained multi-objective optimization problems(CMOPs) include the optimization of objective functions and the satisfaction of constraint conditions, which challenge the solvers.To solve CMOPs, constrained multi-obj... Constrained multi-objective optimization problems(CMOPs) include the optimization of objective functions and the satisfaction of constraint conditions, which challenge the solvers.To solve CMOPs, constrained multi-objective evolutionary algorithms(CMOEAs) have been developed. However, most of them tend to converge into local areas due to the loss of diversity. Evolutionary multitasking(EMT) is new model of solving complex optimization problems, through the knowledge transfer between the source task and other related tasks. Inspired by EMT, this paper develops a new EMT-based CMOEA to solve CMOPs, in which the main task, a global auxiliary task, and a local auxiliary task are created and optimized by one specific population respectively. The main task focuses on finding the feasible Pareto front(PF), and global and local auxiliary tasks are used to respectively enhance global and local diversity. Moreover, the global auxiliary task is used to implement the global search by ignoring constraints, so as to help the population of the main task pass through infeasible obstacles. The local auxiliary task is used to provide local diversity around the population of the main task, so as to exploit promising regions. Through the knowledge transfer among the three tasks, the search ability of the population of the main task will be significantly improved. Compared with other state-of-the-art CMOEAs, the experimental results on three benchmark test suites demonstrate the superior or competitive performance of the proposed CMOEA. 展开更多
关键词 Constrained multi-objective optimization evolutionary multitasking(EMT) global auxiliary task knowledge transfer local auxiliary task
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Auxiliary guidance manufacture and revealing potential mechanism of perovskite solar cell using machine learning
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作者 Quan Zhang Jianqi Wang Guohua Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期146-157,I0004,共13页
To promote the development of global carbon neutrality,perovskite solar cells(PSCs)have become a research hotspot in related fields.How to obtain PSCs with expected performance and explore the potential factors affect... To promote the development of global carbon neutrality,perovskite solar cells(PSCs)have become a research hotspot in related fields.How to obtain PSCs with expected performance and explore the potential factors affecting device performance are the research priorities in related fields.Although some classical computational methods can facilitate material development,they typically require complex mathematical approximations and manual feature screening processes,which have certain subjectivity and one-sidedness,limiting the performance of the model.In order to alleviate the above challenges,this paper proposes a machine learning(ML)model based on neural networks.The model can assist both PSCs design and analysis of their potential mechanism,demonstrating enhanced and comprehensive auxiliary capabilities.To make the model have higher feasibility and fit the real experimental process more closely,this paper collects the corresponding real experimental data from numerous research papers to develop the model.Compared with other classical ML methods,the proposed model achieved better overall performance.Regarding analysis of underlying mechanism,the relevant laws explored by the model are consistent with the actual experiment results of existing articles.The model exhibits great potential to discover complex laws that are difficult for humans to discover directly.In addition,we also fabricated PSCs to verify the guidance ability of the model in this paper for real experiments.Eventually,the model achieved acceptable results.This work provides new insights into integrating ML methods and PSC design techniques,as well as bridging photovoltaic power generation technology and other fields. 展开更多
关键词 Machine learning Carbon neutrality PHOTOVOLTAIC auxiliary experiment design
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Evaluation method for assessing the auxiliary service transaction mechanism in regional power markets
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作者 Le Liu Xueyu Chen +3 位作者 Dexin Li Chang Liu Dunnan Liu Genzhu Li 《Global Energy Interconnection》 EI CAS CSCD 2023年第2期238-252,共15页
Accurate and seamless auxiliary services in the power market can guarantee smooth and continuous power system operation. China’s new round of power system reform has entered a critical period, and reform implementati... Accurate and seamless auxiliary services in the power market can guarantee smooth and continuous power system operation. China’s new round of power system reform has entered a critical period, and reform implementation requires comprehensive improvements in the maturity of the supporting auxiliary service market. This study reviews the development status and evolution path of the European unified power market and the US regional power market, provides experience for the development of China’s regional power market, then identifies the key influencing factors of auxiliary service trading mechanism design in regional power markets. To analyze the rationality of the auxiliary service trading evaluation index, this paper established an evaluation model for assessing regional power markets. Using combined weight optimization, the gray correlation TOPSIS method was applied to comprehensively evaluate auxiliary service trading in the regional power market. Finally, the application of the proposed evaluation method was briefly analyzed to examine four regional power markets in China and evaluate the effectiveness of current market construction in different regions and provide suggestions for future market construction. 展开更多
关键词 Power market auxiliary services Transaction mechanism Evaluation index Evaluation model
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Multi-Objective Optimization Analysis of Auxiliary Flux Modulator Magnetic Gear with Unequal Magnetic Poles
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作者 Zhan Su Libing Jing 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第4期372-378,共7页
To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is proposed.This design incorporates an inner rotor with an as... To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is proposed.This design incorporates an inner rotor with an asymmetric sector and a trapezoidal combined N-S pole structure,featuring Halbach arrays for the arrangement of permanent magnets(PMs).The outer rotor PMs adopt a Spoke-type configuration.To optimize the CMG for high output torque and low torque ripple,a sensitivity analysis is conducted to identify key size parameters that significantly influence the optimization objectives.Based on the sensitivity hierarchy of these parameters,a multi-objective optimization analysis is performed using a genetic algorithm(GA)to determine the optimal structural parameter values of the CMG.In addition,a coaxial magnetic gear(CMG)topology with 4 inner and 17 outer pole pairs is adopted,and the parametric model is established.Finally,the electromagnetic properties of the CMG are evaluated using the finite element method.The results indicate a remarkable reduction in torque ripple,specifically by 46.15%. 展开更多
关键词 auxiliary flux modulator CMG TORQUE Multi-objective optimization Parameter sensitivity
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Auxiliary Classifier of Generative Adversarial Network for Lung Cancer Diagnosis
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作者 P.S.Ramapraba P.Epsiba +1 位作者 K.Umapathy E.Sivanantham 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2177-2189,共13页
The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Net... The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Network(GAN)based Lung Cancer Classification(LCC)system is developed.The pro-posed AC-GAN-LCC system consists of three modules;preprocessing,Lungs Region Detection(LRD),and AC-GAN classification.A Wienerfilter is employed in the preprocessing module to remove the Gaussian noise.In the LRD module,only the lung regions(left and right lungs)are detected using itera-tive thresholding and morphological operations.In order to extract the lung region only,floodfilling and background subtraction.The detected lung regions are fed to the AC-GAN classifier to detect the nodules.It classifies the nodules into one of the two classes,i.e.,binary classification(such as nodules or non-nodules).The AC-GAN is the extended version of the conditional GAN that predicts the label of a given image.Three different optimization techniques,adaptive gradient optimi-zation,root mean square propagation optimization,and Adam optimization are employed for optimizing the AC-GAN architecture.The proposed AC-GAN-LCC system is evaluated on the Lung Image Database Consortium(LIDC)data-base Computed Tomography(CT)scan images.The proposed AC-GAN-LCC system classifies∼15000 CT slices(7310 non-nodules and 7685 nodules).It pro-vides an overall accuracy of 98.8%on the LIDC database using Adam optimiza-tion by a 10-fold cross-validation approach. 展开更多
关键词 Lung cancer generative adversarial network auxiliary classifier image classification system deep learning
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Constrained auxiliary particle filtering for bearings-only maneuvering target tracking 被引量:4
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作者 ZHANG Hongwei XIE Weixin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期684-695,共12页
To track the nonlinear,non-Gaussian bearings-only maneuvering target accurately online,the constrained auxiliary particle filtering(CAPF)algorithm is presented.To restrict the samples into the feasible area,the soft m... To track the nonlinear,non-Gaussian bearings-only maneuvering target accurately online,the constrained auxiliary particle filtering(CAPF)algorithm is presented.To restrict the samples into the feasible area,the soft measurement constraints are implemented into the update routine via the1 regularization.Meanwhile,to enhance the sampling diversity and efficiency,the target kinetic features and the latest observations are involved into the evolution.To take advantage of the past and the current measurement information simultaneously,the sub-optimal importance distribution is constructed as a Gaussian mixture consisting of the original and modified priors with the fuzzy weighted factors.As a result,the corresponding weights are more evenly distributed,and the posterior distribution of interest is approximated well with a heavier tailor.Simulation results demonstrate the validity and superiority of the CAPF algorithm in terms of efficiency and robustness. 展开更多
关键词 BEARINGS-ONLY maneuvering target tracking SOFT measurement constraints CONSTRAINED auxiliary particle filtering(CAPF)
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An adaptive stable observer for on board auxiliary inverters with online current identification strategy 被引量:3
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作者 李蔚 刘友梅 +1 位作者 陈特放 邓江明 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期819-828,共10页
An adaptive stable observer with output current online identification strategy for the auxiliary inverters applied in advanced electric trains, such as high speed railway, urban rail, subway and maglev trains, is prop... An adaptive stable observer with output current online identification strategy for the auxiliary inverters applied in advanced electric trains, such as high speed railway, urban rail, subway and maglev trains, is proposed. The designed observer is used to estimate the state variables, i.e. controllable duty ratio and current components in d-q-o rotary reference frame. The convergence of the observer estimation error is analyzed with consideration of uncertain level variation of input voltage at direct current(DC) side and sufficient conditions are given to prove its practical stability. Experimental results are shown to confirm the effectiveness of the proposed observer. 展开更多
关键词 auxiliary INVERTER ADAPTIVE OBSERVER online identification LYAPUNOV function parameter variation
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Retrospective observation of therapeutic effects of adult auxiliary partial living donor liver transplantation on postpartum acute liver failure: A case report 被引量:3
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作者 Chuan-Yun Li Wei Lai Shi-Chun Lu 《World Journal of Gastroenterology》 SCIE CAS 2015年第9期2840-2847,共8页
We present a female patient with preterm labor, severe viral hepatitis B of acute phase, hepatic encephalopathy stage Ⅲ and coma.After delivery, the illness was exacerbated and the patient presented with clinical sig... We present a female patient with preterm labor, severe viral hepatitis B of acute phase, hepatic encephalopathy stage Ⅲ and coma.After delivery, the illness was exacerbated and the patient presented with clinical signs of vital organ dysfunctions such as acute respiratory distress syndrome, cerebral edema and hypoxemia that needed mechanical ventilation.Emergency liver transplantation was recommended after multidisciplinary panel consultations.The donor, her mother, consented to donate her right liver.Auxiliary partial orthotopic living donor liver transplantion(APOLDLT) was performed.After operation, the patient was on triple medication of tacrolimus plus mofetil mycophenolate and prednisone for immunosuppression.The combination of antihepatitis B virus(HBV) immunoglobulin and entecavir was initiated for anti-HBV therapy.Both the patient and the donor recovered well without any complications.The patient was followed up regularly.Her liver function, clinical signs and symptoms improved significantly.Until now, the recipient has been living for more than 78 mo free of any complications.The APOLDLT is a life-saving modality for rescuing patients with high-risk acute liver failure following HBV infection without available donor and hence is recommended under standardized antiviral therapy coverage as stated above. 展开更多
关键词 auxiliary PARTIAL ORTHOTOPIC living DONOR liver tr
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Ratio-Cum-Product Estimator Using Multiple Auxiliary Attributes in Single Phase Sampling 被引量:4
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作者 John Kung’u Leo Odongo 《Open Journal of Statistics》 2014年第4期239-245,共7页
In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error... In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error are derived. An empirical study is given to compare the performance of the estimator with existing estimators. It has been found that the ratio-cum-product estimator using multiple auxiliary attributes is more efficient than mean per unit, product and ratio estimators using one auxiliary attribute, and Product and Ratio estimators using multiple auxiliary attributes in single phase sampling. 展开更多
关键词 Ratio-Cum-Product ESTIMATOR MULTIPLE auxiliary Attributes Single Phase Sampling Bi-Serial Correlation Coefficient
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Auxiliary partial liver transplantation for acute liver failure using "high risk" grafts: Case report 被引量:1
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作者 Wei-Dong Duan Xi-Tao Wang +3 位作者 Hong-Guang Wang Wen-Bin Ji Hao Li Jia-Hong Dong 《World Journal of Gastroenterology》 SCIE CAS 2016年第5期1919-1924,共6页
Acute liver failure(ALF) is a reversible disorder that is associated with an abrupt loss of hepatic mass, rapidly progressive encephalopathy and devastating complications. Despite its high mortality, an emergency live... Acute liver failure(ALF) is a reversible disorder that is associated with an abrupt loss of hepatic mass, rapidly progressive encephalopathy and devastating complications. Despite its high mortality, an emergency liver transplantation nowadays forms an integral part in ALF management and has substantially improved the outcomes of ALF. Here, we report the case of a 32-year-old female patient who was admitted with grade Ⅳ hepatic encephalopathy(coma) following drug-induced ALF. We performed an emergency auxiliary partial orthotopic liver transplantation with a "high risk" graft(liver macrovesicular steatosis approximately 40%) from a living donor. The patient was discharged on postoperative day 57 with normal liver function. Weaning from immunosuppression was achieved 9 mo after transplantation. A follow-up using CT scan showed a remarkable increase in native liver volume and gradual loss of the graft. More than 6 years after the transplantation, the female now has a 4-year-old child and has returned to work full-time without any neurological sequelae. 展开更多
关键词 Acute LIVER failure auxiliary partial orthotopicliver TRANSPLANTATION FATTY LIVER GRAFT
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Immune protection of auxiliary liver to other allograft: report of 3 cases 被引量:1
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作者 Nian-Qiao Gong Qi-Fa Ye the Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2003年第3期351-353,共3页
OBJECTIVE: To assess the immune status of auxiliary liver transplantation and to clarify the immuneprotection of auxiliary liver to other allograft.METHODS: Immunological markers and pathological changes in 3 patients... OBJECTIVE: To assess the immune status of auxiliary liver transplantation and to clarify the immuneprotection of auxiliary liver to other allograft.METHODS: Immunological markers and pathological changes in 3 patients undergoing auxiliary livertransplantation were analysed.RESULTS: The lower the concentration of immunosuppressive agent, the less the rejection and themilder the intensity in the 3 patients. The function of allograft after auxiliary liver transplantation wasexcellent.CONCLUSIONS: Patients are in a low immune reaction state after auxiliary liver transplantation.Auxiliary liver can protect other allografts by related immunological mechanisms. The side-effects oflow-concentration immunosuppressive agents on auxiliary liver and other allografts are mild. 展开更多
关键词 auxiliary LIVER TRANSPLANTATION IMMUNE protection ALLOGRAFT
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Auxiliary Ligand Oriented CdⅡ-flexible Dicarboxylic Acid Coordination Frameworks:Syntheses, Structures and Properties 被引量:1
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作者 陈勇强 翟佳鑫 +1 位作者 田源 刘秀萍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1311-1319,共9页
Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(... Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(L1 = 3,3’-[1,3-benzenebis(carbonylimino)]bi(benzoate), L2 = 1,3-bi(4-pyridyl)propane, L3 = 4,4’-bipyridine). Complex 1 crystallizes in triclinic, space group P■ with a = 8.7415(5), b = 12.2247(7), c =16.2415(10) ?, β = 95.6790(10)°, V = 1525.11(16) ?3, Dc = 1.553 mg·m-3, C35H28CdN4O6, Mr = 713.02, F(000) = 724, μ(MoKα) = 0.770 mm–1, Z = 2, R/wR(I > 2σ(I))a = 0.0302/0.0773. However, complex 2 crystallizes in monoclinic, space group P21/n with a = 11.4986(7), b = 23.0911(14), c = 11.9943(8) ?, β = 115.9500(10)°, V = 2863.6(3) ?3, Dc = 1.598 mg·m-3, C32H24CdN4O7, Mr = 688.96, F(000) = 1392, μ(MoKα) = 0.820 mm–1, Z = 4, R/wR(I > 2σ(I))a = 0.0283/0.0631. The structures of two complexes were characterized. Complexes 1 and 2 have different one-dimensional(1D) chain structures. In addition, we have also made a preliminary study on the properties of the two complexes. 展开更多
关键词 COORDINATION framework auxiliary LIGAND structure PROPERTY
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Severe skeletal bimaxillary protrusion treated with micro-implants and a self-made four-curvature torquing auxiliary: A case report 被引量:1
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作者 Rui Liu Wan-Bang Hou +4 位作者 Ping-Zhu Yang Lin Zhu Yong-Quan Zhou Xia Yu Xiu-Jie Wen 《World Journal of Clinical Cases》 SCIE 2021年第3期722-735,共14页
BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to ... BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to correct without surgery.Unfortunately,many patients abandon treatment because of fear of surgery.Here,we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments,highlighting an alternative treatment option.CASE SUMMARY A 31-year-old woman wished to address a severe protrusion profile(approximately 8 mm overbite)and gummy smile.Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion,and proclined and protrusive mandibular incisors.Panoramic radiograph showed a missing mandibular right third molar.A diagnosis of severe bimaxillary dentoalveolar protrusion was made.Taking into account the patient’s fear of orthognathic surgery,she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary.The treatment allowed for maximal en masse anterior tooth retraction,proper relocation of incisors,and alleviation of the skeletal class II pattern.Esthetically,the patient’s lip protrusion was significantly decreased as was the overjet(from 10.5 mm to 1.8 mm),and the results remained stable throughout the 2-year followup.CONCLUSION Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults. 展开更多
关键词 ORTHODONTICS Bimaxillary protrusion Micro-implants Self-made fourcurvature torquing auxiliary Teeth Case report
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Effect of Auxiliary Gas Flow Parameters on Microstructure and Properties of Ta Coatings Prepared by Three-Cathode Atmosphere Plasma Spraying 被引量:1
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作者 Jing Cui Haiyang Xia +1 位作者 Lang Cui Guang Liu 《Journal of Beijing Institute of Technology》 EI CAS 2022年第3期302-316,共15页
Based on the three-cathode plasma spraying system,tantalum(Ta)coatings were pre-pared on the substrate of CuCrZr alloy.The effects of different auxiliary gas(helium)flow rates on the microstructure,phase composition,m... Based on the three-cathode plasma spraying system,tantalum(Ta)coatings were pre-pared on the substrate of CuCrZr alloy.The effects of different auxiliary gas(helium)flow rates on the microstructure,phase composition,mechanical and wear resistance properties of Ta coatings were studied.The results showed that the oxidation degree of the coatings decreases first and then increases with the increase of the auxiliary gas flow.When the auxiliary gas flow rate is 70 L·min-1,the oxidation degree of the coating is the lowest,minimum value of the porosity is 0.21%,and the bonding strength reaches the maximum,59.3 MPa.At this time,the coating wear rate is 0.0012 mm^(3)·N^(-1)·m^(-1)with the best wear resistance.This indicates that the auxiliary gas flow has an important influence on the quality and surface mechanical properties of tantalum coating. 展开更多
关键词 plasma spraying tantalum(Ta)coating auxiliary gas flow rate bonding strength tri-bological property
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Auxiliary Teeth Design to Reduce Short-Circuit Current in Permanent Magnet Generators 被引量:2
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作者 Yong He Wenxiang Zhao +1 位作者 Hongyu Tang Jinghua Ji 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第3期198-205,共8页
In this paper,a new auxiliary teeth structure is proposed for fault-tolerant permanent magnet(PM)generators,which can reduce the short-circuit currents.Firstly,the short-circuit current and the phase to phase isolatio... In this paper,a new auxiliary teeth structure is proposed for fault-tolerant permanent magnet(PM)generators,which can reduce the short-circuit currents.Firstly,the short-circuit current and the phase to phase isolation of the fault-tolerant generator are analyzed briefly.Secondly,the auxiliary teeth structure is optimized to improve fault-tolerant capability.Then,the PM generators with different stator structures are compared to evaluate the proposed auxiliary teeth structure.Four critical generator parameters are investigated,i.e.back-electromotive forces,short-circuit currents,stator magneto motive force(MMF)harmonics,and torque performances.The results show that the proposed structure has better fault-tolerant capability than the conventional two-layer windings.Moreover,the stator MMF harmonics can be suppressed.Furthermore,the cogging torque and torque ripple can be suppressed by adopting the proposed structure.Finally,the simulated results are given to validate the theoretical analysis. 展开更多
关键词 auxiliary teeth fault-tolerant generator magneto motive force TORQUE finite-element method permanent magnet generator
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Approximate Solution of Lane-Emden Type Equations Using Variation of Parameters Method with an Auxiliary Parameter 被引量:1
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作者 Asmaa S. Khalifa Hany N. Hassan 《Journal of Applied Mathematics and Physics》 2019年第4期921-941,共21页
Lane-Emden type equation is a nonlinear differential equation appears in many fields such as stellar structure, radioactive cooling and modeling of clusters of galaxies. In this work, this equation is investigated usi... Lane-Emden type equation is a nonlinear differential equation appears in many fields such as stellar structure, radioactive cooling and modeling of clusters of galaxies. In this work, this equation is investigated using a semi-analytical method called the Variation of parameters method with an auxiliary parameter. In the applied technique, an unknown auxiliary parameter is inserted in Variation of Parameters Method to solve some special cases of these equations. The used algorithm is easy to implement and very effective. The obtained solutions are also fairly accurate. 展开更多
关键词 Lane-Emden Equation VARIATION of PARAMETER METHOD (VPM) auxiliary PARAMETER
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A New Regression Type Estimator with Two Auxiliary Variables for Single-Phase Sampling 被引量:1
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作者 Everline Chemutai Tum John Kung’u Leo Odongo 《Open Journal of Statistics》 2014年第9期789-796,共8页
In this paper, we have proposed an estimator of finite population mean using a new regression type estimator with two auxiliary variables for single-phase sampling and investigated its finite sample properties. An emp... In this paper, we have proposed an estimator of finite population mean using a new regression type estimator with two auxiliary variables for single-phase sampling and investigated its finite sample properties. An empirical study has been carried out to compare the performance of the proposed estimator with the existing estimators that utilize auxiliary variables for finite population mean. It has been found that the new regression type estimator with two auxiliary variables for to be more efficient than mean per unit, ratio and product estimator and exponential ratio and exponential product estimators and exponential ratio-product estimator. 展开更多
关键词 Regression ESTIMATOR EXPONENTIAL Ratio-Product ESTIMATOR auxiliary VARIABLES Mean Squared ERROR
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