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Effectiveness of Chromated Copper Arsenate against Deteriorating Agents of Eucalyptus Poles and Posts in Four Eco-Regions in Kenya
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作者 Miriam Gathogo Evanson Omuse George Muthike 《Open Journal of Forestry》 2024年第3期281-296,共16页
Previous studies done elsewhere have shown that Eucalyptus poles treated with chromated copper arsenate (CCA) can last over 30 years. Kenya is exceptional because in some eco-regions, the Eucalyptus poles’ life span ... Previous studies done elsewhere have shown that Eucalyptus poles treated with chromated copper arsenate (CCA) can last over 30 years. Kenya is exceptional because in some eco-regions, the Eucalyptus poles’ life span has greatly reduced to 5 years. The current study was designed to evaluate wood deteriorating agents of CCA-treated Eucalyptus poles and variability in four eco-regions of Kenya, namely, dryland, coastal, highland and humid lake. A total of 360 Eucalyptus pole samples were used for this experiment. Three CCA treatments were used to treat transmission poles at 20 kg/cm3 fencing posts samples at 6 kg/cm3, and a control group. Results indicated that termites and wood-decay fungi attacks caused wood deterioration in the four eco-regions. The proportion of power transmission pole degradation by wood deteriorating agents varied across eco-regions, between treatments and control and between time after treatments. Dryland eco-regions had the highest termite-related degradation (41.82%) while wood-decay fungi attack was highest in the highland eco-regions (9.20%). Samples treated with 6 kg/cm3 recorded the lowest level of wood deterioration, manifested by minimal superficial termite and wood-decay fungi attack. Samples treated with 20 kg/cm3 were characterized by moderate termite and wood-decay fungi attacks observed around the heartwood region, unlike sapwood. This study concluded that the deterioration of Eucalyptus CCA-treated poles is a question of climatic variability and hence, to increase the poles’ lifespan, CCA treatment should be tailored according to the characteristics of the ecoregion of use. Further investigations will inform the diversity of termites and decay-fungi across different eco-regions. 展开更多
关键词 Wood Deteriorating Agents CCA Transmission poles Wood-Decay Fungi
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具有POLE致病性突变子宫内膜癌的临床病理及分子特征分析
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作者 蔡宇梦 周杨 +4 位作者 汪昊 庞钧译 吴焕文 师晓华 梁智勇 《诊断病理学杂志》 2024年第4期282-286,322,共6页
目的探讨具有POLE致病性突变子宫内膜癌(EC)的临床病理及分子特征。方法选取179例EC患者,根据POLE基因突变、错配修复(MMR)蛋白表达及p53表达/TP53突变进行分子分型,分析POLE mut型EC的临床病理及分子特征。结果POLE mut20例,MMRd 48例,... 目的探讨具有POLE致病性突变子宫内膜癌(EC)的临床病理及分子特征。方法选取179例EC患者,根据POLE基因突变、错配修复(MMR)蛋白表达及p53表达/TP53突变进行分子分型,分析POLE mut型EC的临床病理及分子特征。结果POLE mut20例,MMRd 48例,NSMP 90例,p53 abn 21例。POLE mut EC多为FIGOⅠ期(17/20),中-低分化子宫内膜样癌(EEC)(13/20)、局限于内膜/浅肌层(17/20)、肿瘤浸润性淋巴细胞(TILs)显著(17/20)、无/局灶(LVSI)(18/20)、无淋巴结转移(19/20)。4个亚组间临床病理特征的差异均有统计学意义(P<0.05)。POLE mut型预后最好,具有多重分类特征的病例预后更接近POLE mut型。结论POLE mut EC提示着较高的组织学分级,较早的临床分期及较好的预后;POLE mut可继发dMMR/MSI-H表型及p53/TP53异常,应归类为POLE mut型。 展开更多
关键词 子宫内膜癌 分子分型 pole 错配修复缺陷 TP53
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Design Optimization of a Novel Axial-radial Flux Permanent Magnet Claw Pole Machine with SMC Cores and Ferrite Magnets
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作者 Chengcheng Liu Fan Yang +1 位作者 Wenfeng Zhang Youhua Wang 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第4期358-365,共8页
Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current ... Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current loss,and simple manufacturing process.The permanent magnet claw pole machine(PMCPM)with SMC cores is a good case that the SMC to be adopted for developing 3D flux electrical machines.In this paper,a novel axial-radial flux permanent magnet claw pole machine(ARPMCPM)with SMC cores and ferrite magnets is proposed.Compared with the traditional PMCPM,the proposed ARPMCPM is designed with only one spoke PM rotor and its whole structure is quite compact.For the performance prediction,the 3D finite element method(FEM)is used.Meanwhile,for the performance evaluation,a previously developed axial flux claw pole permanent magnet machine(AFCPM)is employed as the benchmark machine and all these machines are optimized by using the combined multilevel robust Taguchi method.It can be seen that the proposed ARPMCPM is with higher torque/weight density and operation efficiency. 展开更多
关键词 Soft magnetic composite(SMC) Permanent magnetic claw pole machine(PMCPM) Axial-radial flux
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Design and Performance Analysis of Permanent Magnet Claw Pole Machine with Hybrid Cores
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作者 Chengcheng Liu Zheng Chao +1 位作者 Shaopeng Wang Youhua Wang 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第3期275-283,共9页
Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for hi... Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for high speed operation. However, because of its complex irregular structure, the manufacturing process using silicon sheets is complicated. Soft magnetic composite material(SMC) is manufactured by powder metallurgy technology, which can produce various shapes of stator core structures, so it is easier to produce various irregular shapes of the stator core. However, the raw SMC material is relatively expensive, and the mechanical strength of SMC is weak. In this paper, a PMCPM with hybrid cores is proposed. With the adoption of hybrid silicon sheet-SMC cores and amorphous alloy-SMC cores, the torque ability of PMCPM can be improved greatly and it can have higher efficiency for more wide operation frequency. Meanwhile, its mechanical strength has been improved and it can be designed for high torque direct drive applications as it is a modular machine. Furthermore, three methods are proposed to reduce the additional eddy current loss which resulted from the employment of hybrid cores in PMCPM. 展开更多
关键词 Permanent magnet claw pole machine(PMCPM) Soft magnetic materials(SMC) Hybrid cores Eddy current loss
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Many Kinds of Reserved Judgement in No-Data Problem
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作者 Houju Hori Jr. 《Applied Mathematics》 2024年第1期1-8,共8页
The reserved judgment can be broadly categorized into three types: Re-Do, Re-Set, and Natural Flowing Case (i.e. step by step in Re-Try). Hori et al. constructed the Bayes-Fuzzy Estimation and demonstrated that system... The reserved judgment can be broadly categorized into three types: Re-Do, Re-Set, and Natural Flowing Case (i.e. step by step in Re-Try). Hori et al. constructed the Bayes-Fuzzy Estimation and demonstrated that system theory can be applied to the possibility of Markov processes, and that decision-making approaches can be applied to sequential Bayes estimation. In this paper, we focus on the Natural Flowing Case within reserved judgment. Here, the possibility of oblique (or principal) factor rotation is considered as a part of the tandem fuzzy system that follows step by step for sequential Bayes estimation. Ultimately, we achieve a significant result whereby the expected utility can be calculated automatically without the need to construct a utility function for reserved judgment. There, this utility in Re-Do can be calculated by the prior utility, and that utility in Re-set does not exist by our research in this paper. Finally, we elucidate the relationship between fuzzy system theory and fuzzy decision theory through an applied example of Bayes-Fuzzy theory. Fuzzy estimation can be applied to only normal making decision, but it is impossible to apply abnormal decision problem. Our Vague, specially Type 2 Vague can be applied to abnormal case, too. 展开更多
关键词 Bayes-Fuzzy Estimation Re-Do Re-Set Indifferent Zone Reserved judgement
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We Live on a Small Space Comet: The Third Extraordinary Motion of Earth towards the North Pole and Its Various Effects
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作者 Walid Nabil 《Advances in Aerospace Science and Technology》 2023年第3期21-33,共13页
The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibratio... The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibrations of traffic, and we listed successive scientific confirmations to indicate the rotation of the planet in a regular movement around its axis once every 24 hours, and it is running in another second movement around the sun once every 365¼ days, so are they only two movements, no more?! Is it possible for him to run at a regular speed in an additional direction? 展开更多
关键词 The Third Additional Regular Movement of the Planet Earth towards the North pole The Movement of the Planet Earth in Space The Spiral Path of the Earth The Speed of the Planet 1.3 Kilometers per Second The Planet Earth A Small Space Comet
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The Performance of Small Diameter Aluminum Light Support Structures Containing Handholes under Cyclic Fatigue
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作者 Cameron R. Rusnak Aya Al-Hamami Craig C. Menzemer 《Open Journal of Civil Engineering》 2024年第2期196-213,共18页
Aluminum light poles play a pivotal role in modern infrastructure, ensuring proper illumination along highways and in populated areas during nighttime. These poles typically feature handholes near their bases, providi... Aluminum light poles play a pivotal role in modern infrastructure, ensuring proper illumination along highways and in populated areas during nighttime. These poles typically feature handholes near their bases, providing access to electrical wiring for installation and maintenance. While essential for functionality, these handholes introduce a vulnerability to the overall structure, making them a potential failure point. Although prior research and analyses on aluminum light poles have been conducted, the behavior of smaller diameter poles containing handholes remains unexplored. Recognizing this need, a research team at the University of Akron undertook a comprehensive experimental program involving aluminum light poles with handholes containing welded inserts in order to gain a better understanding of their fatigue life, mechanical behavior, and failure mechanisms. The research involved testing seven large-scale aluminum light poles each 8-inch diameter, with two separate handholes. These handholes included a reinforcement that was welded to the poles. Finite Element Analysis (FEA), statistical analysis, and comparison analysis with their large counterparts (10-inch diameter) were used to augment the experimental results. The results revealed two distinct failure modes: progressive crack propagation leading to ultimate failure, and rupture of the pole near the weld initiation/termination site around the handhole. The comparison analysis indicated that the 8-inch diameter specimens exhibited an average fatigue life exceeding that of their 10-inch counterparts by an average of 30.7%. The experimental results were plotted alongside the fatigue detail classifications outlined in the Aluminum Design Manual (ADM), enhancing understanding of the fatigue detail category of the respective poles/handholes. 展开更多
关键词 Light pole Handhole Cyclic Fatigue Fatigue Analysis Finite Element Analysis Statistical Analysis
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Surface Magnet Gears with a New Magnet Arrangement and Optimal Shape of Stationary Pole Pieces 被引量:3
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作者 Tomoyuki Fujita Yoshinori Ando +4 位作者 Kosuke Nagaya Masaru Oka Takashi Todaka Masato Enokizono Kazunobu Sugiura 《Journal of Electromagnetic Analysis and Applications》 2013年第6期243-249,共7页
In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without ... In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms. 展开更多
关键词 Magnetic GEAR STATIONARY pole PIECE Optimal Shape HALBACH MAGNET Arrangement
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Design and field measurement of a dipole magnet for a newly developed superconducting proton cyclotron beamline 被引量:1
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作者 Jun-Sheng Zhang Jin-Xing Zheng +3 位作者 Yun-Tao Song Wu-Quan Zhang Ming Li Xian-Hu Zeng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期214-221,共8页
The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magne... The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magnetic field of the dipole is 1.35 T; the bending radius is 1.6 m with a proton beam energy in the range of70–200 Me V. The magnetic field was calculated with 2 D and 3 D simulations, and measured with a Hall mapping system. The pole shim and end chamfer were optimized to improve the field quality. Based on the simulated results,the multipole field components in the good-field region were studied to evaluate the field quality. The results showed that the field quality is better than ± 5 × 10^(-4) at1.35 T with shimming and chamfering. For the transverse field homogeneity, the third-order(B3) and fifth-order(B5)components should be controlled with symmetrical shims.The second-order(B2) component was the main disturbance for the integral field homogeneity; it could be improved with an end chamfer. The magnet manufacturing and field measurement were performed in this project. The measurement results demonstrated that the magnetic design and field quality optimization of the 45° dipole magnet can achieve the desired high field quality and satisfy the physical requirements. 展开更多
关键词 Magnet FIELD quality pole shim End CHAMFER MULTIpole FIELD component
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AN INEQUALITY ON THE ZEROS AND POLES OF VECTOR VALUED MEROMORPHIC FUNCTIONS 被引量:1
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作者 吴昭君 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期380-386,共7页
The author proves that if f : C → C^n is a transcendental vector valued mero-morphic function of finite order and assume, This result extends the related results for meromorphic function by Singh and Kulkarni.
关键词 Characteristic function vector valued meromorphic function ZERO pole
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Collecting Traffic Video Data Using Portable Poles: Survey, Proposal, and Analysis 被引量:2
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作者 Morten B. Jensen Chris H. Bahnsen +2 位作者 Harry S. Lahrmann Tanja K. O. Madsen Thomas B. Moeslund 《Journal of Transportation Technologies》 2018年第4期376-400,共25页
Several initiatives have been launched to help prevention of traffic accidents and near-accidents across the European Union. To aid the overall goal of reducing deaths and injuries related to traffic, one must underst... Several initiatives have been launched to help prevention of traffic accidents and near-accidents across the European Union. To aid the overall goal of reducing deaths and injuries related to traffic, one must understand the causation of the traffic accidents in order to prevent them. Rather than deploying a person to physically monitor a location, the task is eased by camera equipment installed in existing infrastructure, e.g. poles, and buildings, etc. In rural areas there is however a very limited infrastructure available which complicates the data acquisition. But even if there is infrastructure available in either the rural area or the urban area, this might not serve as an ideal position to capture video data from. In this work, we survey and provide an overview of available and relevant portable poles setups with respect to capturing data in both urban areas and rural areas. The conclusion of the survey shows a lack of a mobile, lightweight, compact, and easy deployable portable pole. We therefore design and develop a new portable pole meeting these requirements. The new proposed portable pole can be deployed by 2 persons in 2 hours in both rural areas as well as urban areas due to its compactness. The deployment and usage of the new portable pole is a complimentary tool, which may improve the camera capturing angle in case existing infrastructure is insufficient. This ultimately improves the traffic monitoring opportunities. Further, the survey of selected portable poles provides an excellent overview and can aid multiple applications within road traffic. 展开更多
关键词 Road TRAFFIC Video ANALYSIS Camera MOUNTING pole PORTABLE
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Aerial observations of sea ice and melt ponds near the North Pole during CHINARE2010 被引量:4
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作者 LI Lanyu KE Changqing +2 位作者 XIE Hongjie LEI Ruibo TAO Anqi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期64-72,共9页
An aerial photography has been used to provide validation data on sea ice near the North Pole where most polar orbiting satellites cannot cover. This kind of data can also be used as a supplement for missing data and ... An aerial photography has been used to provide validation data on sea ice near the North Pole where most polar orbiting satellites cannot cover. This kind of data can also be used as a supplement for missing data and for reducing the uncertainty of data interpolation. The aerial photos are analyzed near the North Pole collected during the Chinese national arctic research expedition in the summer of 2010(CHINARE2010). The result shows that the average fraction of open water increases from the ice camp at approximately 87°N to the North Pole, resulting in the decrease in the sea ice. The average sea ice concentration is only 62.0% for the two flights(16 and 19 August 2010). The average albedo(0.42) estimated from the area ratios among snow-covered ice,melt pond and water is slightly lower than the 0.49 of HOTRAX 2005. The data on 19 August 2010 shows that the albedo decreases from the ice camp at approximately 87°N to the North Pole, primarily due to the decrease in the fraction of snow-covered ice and the increase in fractions of melt-pond and open-water. The ice concentration from the aerial photos and AMSR-E(The Advanced Microwave Scanning Radiometer-Earth Observing System) images at 87.0°–87.5°N exhibits similar spatial patterns, although the AMSR-E concentration is approximately 18.0%(on average) higher than aerial photos. This can be attributed to the 6.25 km resolution of AMSR-E, which cannot separate melt ponds/submerged ice from ice and cannot detect the small leads between floes. Thus, the aerial photos would play an important role in providing high-resolution independent estimates of the ice concentration and the fraction of melt pond cover to validate and/or supplement space-borne remote sensing products near the North Pole. 展开更多
关键词 sea ice melt pond albedo concentration aerial observation North pole
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Interdecadal and decadal variation of temperature over North Pole area and the relation with solar activity 被引量:1
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作者 QU Weizheng ZHAO Jinping DU Ling HUANG Fei FAN Tingting 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期53-61,共9页
Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere t... Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere tends to be increased either in winter or in summer.The air temperature has increased 1.3 °C for about 50 years at a speed about 0.025 °C/year in January,and 0.013 °C/year in July.The air temperature in the middle layer of the stratosphere (10 hPa) in January has increased 10 °C.The temperature rising speed in July is 0.14 °C/year.Generally speaking,the temperature rising speed is quicker in winter than in summer and quicker in the upper layer than at the earth surface.b.The air temperature at the top layer of the troposphere (100 hPa) over the North Pole area tends to be increased either in winter or in summer.The air temperature in January has decreased 5.0 °C for about 50 years at a temperature decreasing speed about 0.094 °C/year,and at a temperature decreasing speed about 0.032 °C/year in July.The speed of the temperature decreasing is greater in winter than in summer.c.Periodicity.The air temperature respectively at different altitudes over the North Pole possesses interdecadal variation with a period of 22 years.In July the amplitude of the variation with a period of 22 years decreases rapidly from the high altitude to the low.This means that the 22–year’s period is more obvious at the high altitude than at the low altitude.At the earth surface layer in North Pole there also is obvious decadal variation with a period of 11 years.The analysis indicates that the 22-years’ period temperature variation is associated with the periodic variation of the solar magnetic field.The 11-year period temperature variation is corresponding to 11 year’ period of the variation of the sunspot number. 展开更多
关键词 decadal variation of air temperature solar activity North pole area
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Analytical Signal and Reduction to Pole Interpretation of Total Magnetic Field Data at Eppawala Phosphate Deposit 被引量:1
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作者 N. D. Subasinghe W. K. D. G. D. R. Charles S. N. De Silva 《Journal of Geoscience and Environment Protection》 2014年第3期181-189,共9页
A magnetic survey was carried out to find out the possibilities of demarcating a phosphate deposit from the surrounding country rocks. It is a well-established fact that the magnetic mapping can be utilised to investi... A magnetic survey was carried out to find out the possibilities of demarcating a phosphate deposit from the surrounding country rocks. It is a well-established fact that the magnetic mapping can be utilised to investigate the subsurface objects, materials or different rock types based on their magnetic properties. Those rocks with ferro-magnetic minerals such as magnetite generate magnetic anomalies which in turn help to investigate the subsurface occurrence of mineral deposits. An economic phosphate deposit in Sri Lanka, known as Eppawala Phosphate deposit was selected for this study. The deposit was formed as an accumulation of secondary products of an apatite-rich carbonatite. Due to weathering of iron-rich carbonatite, magnetite and its derivatives are intimately bound with the said deposit. Therefore, the magnetic signature of the phosphate body is different to that of the surrounding country rocks. Despite some studies on different aspects of the deposit, subsurface extents of the ore body are so far not adequately studied. Therefore, this study was conducted to identify the boundaries of the phosphate body. The study was carried over an area of 12 km2 5 km north from the current mining site and survey was conducted. GSM-19 Overhouser system with integrated GPS was used to collect field data. Magnetic anomalies were plotted using a predefined grid. The maximum positive and negative anomalies encountered in the survey area are 690 nT and 829 nT respectively. This study showed that magnetite is not distributed evenly in the area and the deposit extended along the north south direction. Further, processing of analytical signal using the anomalies showed that the carbonatite occurs as a continuous body trending in North South direction. Low magnetic latitudes magnetic data interpretation is difficult because the vector nature of the magnetic field. Therefore, “reduction to pole” concept and “analytical signal concept” were used for the data analysis. Reduction to pole map and analytical signal map are comparatively similar and the change of declination value has no significant effect on the map of reduction to pole. 展开更多
关键词 MAGNETIC ANOMALY ANALYTICAL SIGNAL REDUCTION to pole
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The Method for Measuring the Loop Resistance and the Temperature Rise Calculation of GIS Conductor Pole 被引量:1
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作者 Li Zhou Tiecheng Lu Bo Zhang 《Journal of Power and Energy Engineering》 2015年第4期306-312,共7页
This paper studies the method for measuring the loop resistance of GIS conductor pole based on the super capacitor producing impulse current up to several thousand amperes. This method overcomes the limitations of con... This paper studies the method for measuring the loop resistance of GIS conductor pole based on the super capacitor producing impulse current up to several thousand amperes. This method overcomes the limitations of conventional diagnostic method. Typical GIS conductor poles are chosen. Based on FEA and lab tests, the effect of different forms of current and contact condition, relationship between the temperature of contact and the loop resistance is researched. In full- scale testing under realistic operating conditions on the new 220 kV GIS using prototype instrumentation a very good sensitivity in an early stage was obtained. 展开更多
关键词 The METHOD for MEASURING the Loop Resistance and the Temperature RISE CALCULATION of GIS Conductor pole
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An Improvement on Data-Driven Pole Placement for State Feedback Control and Model Identification 被引量:1
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作者 Pyone Ei Ei Shwe Shigeru Yamamoto 《Intelligent Control and Automation》 2017年第3期139-153,共15页
The recently proposed data-driven pole placement method is able to make use of measurement data to simultaneously identify a state space model and derive pole placement state feedback gain. It can achieve this precise... The recently proposed data-driven pole placement method is able to make use of measurement data to simultaneously identify a state space model and derive pole placement state feedback gain. It can achieve this precisely for systems that are linear time-invariant and for which noiseless measurement datasets are available. However, for nonlinear systems, and/or when the only noisy measurement datasets available contain noise, this approach is unable to yield satisfactory results. In this study, we investigated the effect on data-driven pole placement performance of introducing a prefilter to reduce the noise present in datasets. Using numerical simulations of a self-balancing robot, we demonstrated the important role that prefiltering can play in reducing the interference caused by noise. 展开更多
关键词 DATA-DRIVEN Control STATE FEEDBACK pole PLACEMENT Nonlinear Systems
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Design and Optimization of Segmented PM Consequent Pole Hybrid Excited Flux Switching Machine for EV/HEV Application 被引量:6
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作者 Wasiq Ullah Faisal Khan Muhammad Umair 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第3期206-214,共9页
Hybrid Excited Flux Switching Machines(HEFSMs)unique feature of high torque density(T_(den))of Permanent Magnet(PM)machines and flux regulation capability of wound field excitation machines.Due to aforesaid unique fea... Hybrid Excited Flux Switching Machines(HEFSMs)unique feature of high torque density(T_(den))of Permanent Magnet(PM)machines and flux regulation capability of wound field excitation machines.Due to aforesaid unique features,stator active HEFSMs are preferred for EV/HEV applications.In this paper a new Segmented PM Consequent Pole HE-FSM(SPMCPHEFSM)with flux bridge is proposed for EV/HEV.The developed SPMCPHEFSM exhibits improved flux modulation and flux regulation capability at reduced PM usage(suppressed PM volume by 46.52%and PM cost by 46.48%)and eliminating stator leakage flux.First,SPMCPHEFSM is geometric optimized(GO)for investigating influence of leading design with key performance indicators such as flux linkage(Ф_(pp)),average torque(T_(avg)),cogging torque(T_(cog)),T_(den),average power(P_(avg))and power density(P_(den))and then proceeded optimized model to structure modification for optimal stator design and position of field excitation coils(FEC).Comprehensive performance analysis reveals that the developed SPMCPHEFSM show improvedФ_(pp)maximum up to 9.11%,improved T_(avg)maximum up to 23.63%,truncate T_(cog)up to 18.9%whereas T_(den)and P_(den)are boost up to 23.55%and 89.72%respectively. 展开更多
关键词 Electric Vehicle Hybrid Electric Vehicle Consequent pole Finite Element Analysis Optimization Segmented PM
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Reduction of Cogging Torque and Electromagnetic Vibration Based on Different Combination of Pole Arc Coefficient for Interior Permanent Magnet Synchronous Machine 被引量:7
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作者 Feng Liu Xiuhe Wang +2 位作者 Zezhi Xing Aiguo Yu Changbin Li 《CES Transactions on Electrical Machines and Systems》 CSCD 2021年第4期291-300,共10页
Cogging torque and electromagnetic vibration are two important factors for evaluating permanent magnet synchronous machine(PMSM)and are key issues that must be considered and resolved in the design and manufacture of ... Cogging torque and electromagnetic vibration are two important factors for evaluating permanent magnet synchronous machine(PMSM)and are key issues that must be considered and resolved in the design and manufacture of high-performance PMSM for electric vehicles.A fast and accurate magnetic field calculation model for interior permanent magnet synchronous machine(IPMSM)is proposed in this article.Based on the traditional magnetic potential permeance method,the stator cogging effect and complex boundary conditions of the IPMSM can be fully considered in this model,so as to realize the rapid calculation of equivalent magnetomotive force(MMF),air gap permeance,and other key electromagnetic properties.In this article,a 6-pole 36-slot IPMSM is taken as an example to establish its equivalent solution model,thereby the cogging torque is accurately calculated.And the validity of this model is verified by a variety of different magnetic pole structures,pole slot combinations machines,and prototype experiments.In addition,the improvement measure of the machine with different combination of pole arc coefficient is also studied based on this model.Cogging torque and electromagnetic vibration can be effectively weakened.Combined with the finite element model and multi-physics coupling model,the electromagnetic characteristics and vibration performance of this machine are comprehensively compared and analyzed.The analysis results have well verified its effectiveness.It can be extended to other structures or types of PMSM and has very important practical value and research significance. 展开更多
关键词 Cogging torque different combination of pole arc coefficient electromagnetic vibration interior permanent magnet synchronous machine
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Expedition to Mars North Pole and Creation There a Scientific Research Base 被引量:1
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作者 Alexander Rubinraut 《Advances in Aerospace Science and Technology》 2020年第1期20-43,共24页
A project of the expedition to the north pole of Mars, which is carried out in two stages, has been developed. In the first stage, a space refueller and a mobile solar battery are delivered to the icy surface of the n... A project of the expedition to the north pole of Mars, which is carried out in two stages, has been developed. In the first stage, a space refueller and a mobile solar battery are delivered to the icy surface of the north pole of Mars. The delivery is carried out with the help of electric rocket ER-7, driven by the electric rocket engine “MARS”, and the source of electricity is a solar battery from gallium arsenide. In the second stage, the space train is formed from two interconnected ER-7 rockets and an orbital takeoff-landing capsule TLC-2, in which three astronauts land on the surface and carry out a complex of physical, biological and geological researches on Mars surface. The space refueller has been developed, which melts the water ice on the surface of Mars and with the help of an electrolyser and a liquefier produces fuel and oxidizer for the operation of the chemical rocket engine of the takeoff-landing capsule. To move astronauts from the north pole to the equator, a spacecraft—?marsoplane, which consists of the electric rocket ER-7 and the takeoff-landing capsule TLC-1 is developed. The duration of the expedition is 110 days at a cost of 2 billion dollars. 展开更多
关键词 MARS NORTH pole Electrical Rocket ER-7 Takeoff-Landing Capsule TLC-1 and TLC-2 Space Refueller Marsoplane Superconducting Electrorocket Engine MARS
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Design and Analysis of Asymmetric Rotor Pole Type Bearingless Switched Reluctance Motor 被引量:1
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作者 Zhenyao Xu Qingguo Yu Fengge Zhang 《CES Transactions on Electrical Machines and Systems》 CSCD 2022年第1期3-10,共8页
Bearingless switched reluctance motor(BSRM) not only combines the merits of bearingless motor(BM) and switched reluctance motor(SRM), but also decreases the vibration and acoustic noise of SRM, so it could be a strong... Bearingless switched reluctance motor(BSRM) not only combines the merits of bearingless motor(BM) and switched reluctance motor(SRM), but also decreases the vibration and acoustic noise of SRM, so it could be a strong candidate for high-speed driving fields. Under the circumstances, a 12/14 BSRM with hybrid stator pole has been proposed due to its high output torque density and excellent decoupling characteristics between torque and suspension force. However, this motor has torque dead-zone, which leads to problems of self-start at some rotor positions and large torque ripple during normal operation. To solve the existing problems in the 12/14 type, an asymmetric rotor pole type BSRM is proposed. The structure and design process of the proposed motor is presented in detail. The characteristics of the proposed motor is analyzed and compared with that of the 12/14 type. Furthermore, prototype of the proposed structure is designed, manufactured and experimented. Finally, simulation and test results are illustrated and analyzed to prove the validity of the proposed structure. 展开更多
关键词 Asymmetric rotor pole bearingless switched reluctance motor self-start torque ripple reduction
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