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能源与动力工程（美国大卫英文） 2016年第3期10卷 183-190页

作者： pedram Asef Ramon Bargallo Perpina Department of Electrical Engineering Polytechnic University of Catalonia-BarcelonaTech Barcelona CAT 08036 Spain

A 3-D FEA (finite element analysis) transient and steady-state design proposal for high-speed with Nd-Fe-Br (reversible) magnets in aerospace application will be examined under design considerations of n = 12,000 rpm, short-duty, sinusoidal drive, low cogging, high efficiency at peak torque, and etc. for an ARWM (aerospace retraction wheel motor). In construction, the PMs (permanent magnets) fixed on the rotor core which is surface-mounted magnets retained by a carbon-fiber bandage. Redundant windings, resistant to fault propagation have accounted. Besides, an axial water-jacket housing without end-cap cooling has involved. All performed characteristic performances of the correlated ARWM will verify by comparison through 2-D and 3-D FEA results. In this paper, design process has dealing with determination of various kinds of losses such as electromagnetic and mechanical losses. In terms of both classified losses, copper, stator back iron, stator tooth, PM, rotor back iron, air-friction and sleeve losses were calculated. The 3-D end-winding effects were included in the modeled ARWM by the authors.

关键词：电磁场分析航空航天三维有限元分析机械损失电机回用设计过程转子铁芯

Design of High-Speed PM Synchronous Motor Thermal and Mechanical Analyzes Study for Aerospace Retraction Wheel Motor Application

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Journal of Energy and Power Engineering 2016年第4期10卷 258-267页

作者： pedram Asef Ramon Bargallo Perpina Department of Electrical Engineering Polytechnic University of Catalonia-BarcelonaTech Barcelona CA T 08036 Spain

A 3-D modeling of FEA (finite element analysis) design provides for high-speed synchronous with PMs (permanent magnets) applied in aerospace application will be examined under design considerations of n = 12,000 rpm, short-duty operation, and etc. for an ARWM (aerospace retraction wheel motor). First, lumped-elements will be fine-tuned following numerical method results is reported steady-state and transient solutions. Besides, the equations of thermal modeling such as Re, Nu, Gr and Pr numbers in order to calculate heat-transfer coefficient of convection on the rotor and stator surfaces in the air-gap have calculated. This section illustrates the temperature distribution of each point in a clear view. By CFD (fluid dynamic analysis) analysis, the fluid dynamics were modeled, pressure and velocity streamlines of cooling-flow have analyzed. An optimization algorithm was derived in order to have optimized number of water-channels as well. Second, calculation of nodal and tangential forces which deal with mechanical stresses of the ARWM have represented. The paper discusses an accurate magnetic-field analysis that addresses equivalent stress distribution in the magnetic core through using the transient FEA to estimate motor characteristics. The whole model shear and normal mechanical stresses and total deformation of the ARWM has been investigated by transient FEA. The end-winding effects were included by the authors.

关键词：永磁同步电机热机械分析应用流体动力学模型有限元分析对流换热系数应力计算航天领域

造纸过程中固着剂与溶解和胶体物质间的相互作用研究

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中国造纸 2017年第11期 80-80页

作者： LIJUN WANG YIQIAN ZHANG XUEJIN ZHANG pedram FATEHI

固着剂通常为高度阳离子和低分子质量的聚电解质,广泛应用于造纸工业,用来将溶解和胶体物质(DCS)附着到木材纤维上,并将其从造纸系统中除去。然而,固着剂与DCS之间的相互作用仍然不太明确。在本研究中,以氧化淀粉、树脂酸及其混合物分... 详细信息

固着剂通常为高度阳离子和低分子质量的聚电解质,广泛应用于造纸工业,用来将溶解和胶体物质(DCS)附着到木材纤维上,并将其从造纸系统中除去。然而,固着剂与DCS之间的相互作用仍然不太明确。在本研究中,以氧化淀粉、树脂酸及其混合物分别作为模拟造纸配料中溶解物质(DS)、胶体物质(CS)及溶解和胶体物质(DCS)的模型。实验采用3种不同的多胺固着剂(PA)进行处理,并通过分析固液分离后模型化合物的残留浓度来评价其对系统稳定性的影响。DS与CS的相互作用可以由实验结果来推断。在单一系统中,固定剂除去氧化淀粉的效果比较差,而除去树脂酸的效果比较好。然而,在混合DCS系统中,氧化淀粉的去除得到改善,而树脂酸的去除则变差。结果表明,当混合DCS系统中加入固着剂时,首先将DS改为DS-聚电解质复合物(PEC),并将PEC连接到CS颗粒表面,提高后者的稳定性,使其更难以被去除。另一方面,一旦CS稳定性受到干扰并且有絮聚发生,与单一的DS系统相比,更多的DS可以被去除。

关键词：溶解和胶体物质固着剂多胺聚电解质配合物胶体絮聚

Effects of Subcutaneous Fat Stores on Serum Phospholipids and Nonesterified Fatty Acid Lipid Fractions in Periparturient Dairy Cows

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Journal of Agricultural Science and Technology(B) 2014年第5期4卷 352-359页

作者： Cynthia Madeleine Scholte pedram Rezamand Shannon Louise Shields Kirk Christen Ramsey Department of Animal and Veterinary Science University of Idaho Moscow 83843 Idaho USA

Negative energy balance in early lactating dairy cows results in a massive release of fatty acids (FA) into the blood in nonesterified fatty acids (NEFA) form. Large quantities of circulating NEFA may alter the serum FA profile of phospholipids (PL) fraction, which is responsible for cellular plasma membrane integrity and intercellular signaling. The objective of this study was to determine the effects of subcutaneous fat stores, as assessed by body condition score (BCS) on a scale of one to five, around the time of calving and the subsequent lipomobilization on FA profile of serum NEFA and PL lipid fractions, and on productive performance. Based on BCS, cows were retrospectively dichotomized into two groups: over-conditioned (BCS ≥ 3.25) and control (BCS ≤ 3.0). 22 cows had serum samples obtained at -28, -7, 8, 18 and 28 d relative to parturition and analyzed for the FA profile of the NEFA and PL fractions. As expected, over-conditioned cows had greater total plasma NEFA concentrations and decreased dry matter intake. Milk yield and composition did not differ between groups. More importantly however, several FA in the NEFA fraction of plasma lipids varied significantly, including C14:1, C16:0, C18:0 and C20:3n3. In the PL fraction, other FA varied significantly by BCS around time of parturition, including C16:0, C17:0, total C18:2 cis, and C20:2. In summary, BCS did affect FA profile of serum NEFA and PL lipid fractions. This may have drastic consequences for circulating immune cells and their ability to fight infection by altering their FA profile.

关键词：非酯化脂肪酸围产期奶牛脂质成分皮下脂肪血清磷脂储存游离脂肪酸

Total Tract Apparent Digestibility, Serum Fatty Acid Profile, and Productive Performances of Mid-lactating Dairy Cows Fed with Dietary Betaine

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Journal of Agricultural Science and Technology(A) 2020年第5期10卷 237-246页

作者： Hao-Che Hung Chia-Yu Tsai Gwinyai Chibisa Mireille Chahine pedram Rezamand Deptartment of Animal Veterinaryand Food SciencesUniversity of IdahoMoscowIdaho 83844-2330USA Twin Falls Research and Extention Center University of IdahoMoscowIdaho 83844-2330USA

It is hypothesized that betaine supplementation improves production performance in mid-lactation dairy ***-one mid-lactation dairy cows were assigned to a 3×3 Latin square design with three periods of 28 d each and fed three treatments of betaine(0,100,and 200 g/d).Milk samples were collected on day 21 and day 28 of each *** days 21 to 28,cows were fed with chromic oxide(15 g/d per cow).On days 26 to 28,fecal samples were collected to determine apparent total tract nutrient *** samples were obtained on days 26 to 28 of each period for fatty acid(FA)*** were analyzed using the Proc Mixed in *** total tract dry matter(DM)digestibility tended to be greater for cows supplemented with 100 g betaine as compared to no dietary betaine(61 vs.58±1%;p=0.1).In contrast,DM intake(DMI),milk fat percent,milk yield,energy-corrected milk(ECM)yield,and milk FA composition did not differ among *** of betaine can decrease the serum saturated FA C11,C12,C15 and C17,total monounsaturated FA,and C18:2 all trans-9,*** addition,total serum n-3 polyunsaturated FA was significantly *** result can decrease total serum n-6 to n-3 ratio(6.80,7.07,and 6.50±0.16%,for 0,100,and 200 g betaine,respectively;p=0.04).Overall,even betaine supplementation did not change DMI or production,betaine could affect the DM digestibility and serum FA biosynthesis.

关键词： Betaine supplementation apparent total tract nutrient digestibility production performance

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低功耗双边沿触发器的逻辑设计

电子学报 1999年第5期27卷 129-131页

作者：吴训威韦健浙江大学电子工程系美国南加州大学电气工程系统系

本文从消除时钟信号冗余跳变而致的无效功耗的要求出发，提出双边沿触发器的设计思想与基于与非门的逻辑设计．用ＰＳＰＩＣＥ程序模拟证实了该种触发器具有正确的逻辑功能，能够正常地应用于时序电路的设计，并且由于时钟工作频率减半... 详细信息

本文从消除时钟信号冗余跳变而致的无效功耗的要求出发，提出双边沿触发器的设计思想与基于与非门的逻辑设计．用ＰＳＰＩＣＥ程序模拟证实了该种触发器具有正确的逻辑功能，能够正常地应用于时序电路的设计，并且由于时钟工作频率减半而导致系统功耗的明显降低．

关键词：低功耗触发器逻辑设计集成电路

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Analysis of Demagnetizer Operation Using the Finite Element Method

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Journal of Energy and Power Engineering 2010年第2期4卷 58-64页

作者： N. Morovvati H. Feshki Farahani M. Sabaghi S.M. pedram Razi Islamic Azad University Ashtian Branch Ashtian Iran Laser and Optics Research Center NSTRI Tehran Iran Islamic Azad University Tehran South Branch Tehran Iran

Permanent magnets with high energy products are widely used in a variety of electromagnetic devices. Such devices can be found in marine, aerospace, and robotic applications which require the minimization of weight and volume of the electromagnetic device. During the magnetizing process, the magnet may not be perfectly magnetized. Therefore, it needs to be demagnetized. Because of high coercivity of some permanent magnets, the demagnetization process requires the intense magnetic fields in close proximity with the magnetic material. The fields must be produced for a short period of time (millisecond range) and they also must be bidirectional in order to overcome the coercivity of magnetic material. Different parameters have been known to affect the demagnetizer operation such as the core shape, core material, turn number, cross section of air gap, magnet type and so on. The amplitude and waveform of the fixture current is obtained from PSPICE simulations and also from experimental measurement. A 2D finite element analysis is developed to simulate the magnetic fields and the mechanical forces. In this paper, the main parameters affecting the optimal design of the demagnetizer are discussed. Simulation results show that the core structure, air gap width, and turn numbers are the most important parameters when designing such a device.

关键词：有限元方法运行分析 PSPICE模拟脱磁器二维有限元分析机器人应用永磁材料电磁装置

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丹麦NOMA Lab餐厅

现代装饰 2012年第7期 62-67页

作者： Kasper Guldager Jorgensen Kim Herforth Nielsen Andr van Leth Lila Held Morten Norman Lund Lars-Erik Eriksson pedram Seddighzadeh Matthew Scarlett Bjork Christensen Kyle Baumgardner Elliot Mistur Tore Banke Simon McKenzie Jacob Hilmer Adam Mork 代照 3XN公司

NOMAL Lab譬厅在知名的mew0Hds50b划com厨站连续两年蝉联餐厅粪冠军．这样的荣誉让餐厅对新的室内装饰改造有了比以往更高的期望，他们希望创造一座激发想象的试验馆。

关键词： Lab NOMA 餐厅丹麦室内装饰 com

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丹麦NOMA食品实验室

设计家 2012年第2期 84-89页

作者： KIm Herforth Nielsen Kasper Guldager J rgensen Andr van leth lila Held Morten Norman Lund Lars-Erik Eriksson pedram Seddighzadeh Matthew Scarlett BjHrk Christensen Kyle Baumgardner Elliot Mistur Tore Banke Simon McKenzie Jacob Hilmer Pauline Pan GXN

由3XN负责的NOMA食品实验室室内设计项目巧妙地将烹饪与建筑融为一体．并为北欧菜肴打造出最佳的效果呈现舞台。

关键词： NOMA 实验室食品丹麦设计项目

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