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171.
The use of design method considering a coil temperature to maximize the thrust density of a double side coreless permanent
magnet linear synchronous motor (PMLSM) was presented. The optimal current density where the coil temperature reaches an allowable
temperature with heat analysis was applied to a magnetic circuit design. Changing optimal current density is verified whenever
the design parameters of the motor are altered. The design parameters of the motor were applied to thrust calculation. In
this way, the optimal model, which is a reversal of the existing design method, is deduced. The results were compared with
the experimental data to verify their validity. When the convection heat transfer coefficient is applied to other models,
the results of the analysis and test values show good concordance. The method proposed has some limitations. 相似文献
172.
A discontinuity of magnetic circuits according to the end effect is generated in the permanent magnet linear synchronous motor (PMLSM).Due to the unbalanced back electro-motive force (EMF) and impedance produced,unbalanced current is generated.The circulating current,which is caused by a decrease in the thrust,is generated by the unbalanced current.The optimal design of auxiliary-teeth at the end of the mover was carried out to solve the unbalance of phase by using design of experiment (DOE),and compared wi... 相似文献
173.
通过不同温度热挤压处理、力学性能测试和组织形貌观察,研究了热挤压处理对AZ31-0.25%Sb镁合金组织与性能的影响.结果表明:热挤压处理可有效提高合金的力学性能,经220 ℃热挤压处理,合金的室温抗拉强度由263 MPa提高到297.6 MPa,屈服强度由96 MPa提高到222.1 MPa,提高幅度达131.4%;热挤压处理提高AZ31-0.5Sb%合金强度的原因是:挤压期间产生了形变强化和发生的动态再结晶,形变产生的高密度位错可提高合金的抗拉强度,而发生动态再结晶形成的细小晶粒可有效提高合金的屈服强度. 相似文献
174.
Ln0.6Sr0.4Co0.8Fe0.2O3 (Ln=La, Pr, Nd, Sm) perovskite-type complex oxides were synthesized using a glycine-nitrate process, and the structure, electrical conducting and thermal expansion properties of the resulting ceramics were examined with regard to the nature of the lanthanide cations. The results indicated that the La, Pr and Nd specimens had a rhombohedral symmetry, while an orthorhombic structure was determined for the Sm specimen. The pseudo-cubic lattice constant decreased with smaller lanthanide cations. It was found that the electrical conducting properties declined with decreasing lanthanide cation size. Fortunately, all the compositions remained rather high electrical conductivities exceeding 650Ω1.cm-1 in the intermediate temperature range (600-800℃). An appreciable thermal expansion increase at high temperatures was detected for all the compositions. Decreasing the size of the lanthanide cations resulted in an increase of thermal expansion. With respect to the high electrical conductivities, the Ln0.6Sr0.4Co0.8Fe0.2O3 oxides are considered to be acceptable as mixed conducting component in composite cathode designs together with doped ceria electrolytes. 相似文献
175.
Depth enhancement of 3D microscopic living‐cell image using incoherent fluorescent digital holography 下载免费PDF全文
Multilayer images of living cells are typically obtained using confocal or multiphoton microscopy. However, limitations on the distance between consecutive scan layers hinder high‐resolution three‐dimensional reconstruction, and scattering strongly degrades images of living cell components. Consequently, when overlapping information from different layers is focused on a specific point in the camera, this causes uncertainty in the depiction of the cell components. We propose a method that combines the Fresnel incoherent correlation holography and a depth‐of‐focus reduction algorithm to enhance the depth information of three‐dimensional cell images. The proposed method eliminates overlap between light elements in the different layers inside living cells and limitations on the interlayer distance, and also enhances the contrast of the reconstructed holograms of living cells. 相似文献
176.
Precise observation of C. elegans dynamic behaviours under controlled thermal stimulus using a mobile phone–based microscope 下载免费PDF全文
We investigated the temperature‐dependent locomotion of Caenorhabditis elegans by using the mobile phone–based microscope. We developed the customized imaging system with mini incubator and smartphone to effectively control the thermal stimulation for precisely observing the temperature‐dependent locomotory behaviours of C. elegans. Using the mobile phone–based microscope, we successfully followed the long‐term progress of specimens of C. elegans in real time as they hatched and explored their temperature‐dependent locomotory behaviour. We are convinced that the mobile phone–based microscope is a useful device for real time and long‐term observations of biological samples during incubation, and can make it possible to carry out live observations via wireless communications regardless of location. In addition, this microscope has the potential for widespread use owing to its low cost and compact design. 相似文献
177.
我们把注意力投向了“自然意志”之间悖论性的循环机制,在这种机制下从jungrang溪冲积下来的淤沙创造了岛屿,而人们为了控制洪水不断努力地清理着这些淤泥。我们同时无意间揭示了一个事实,疏清出来的淤泥被归为一种“工业废弃物”。我们希望做的是利用这种由溪流不断提供的将汉江与首尔之城重新联系的自然资源。虽然我们始自虚无,希冀的却是那无穷的扩展。我们相信自己在这个项目的场地中所做的工作会扩展到超过其预期的尺度。 相似文献
178.
韩国有一道坚固的防御工事用以抵御朝鲜的入侵,它的名字叫做“防御坦克的墙”。这座20世纪70年代在韩国首都首尔建起的防御墙成为冷战时期的纪念碑,也勾起韩国民众对朝鲜战争的痛苦回忆。 相似文献
179.
180.
The paper proposes a colorfulness enhancement of pictorial images using image classifier based on chroma histogram.This ap-poach firstly estimates strength of colorfulness of images and their types.With such determined information,the algorithm automatically adjusts image colorfulness for a better natural image look.With the help of an additional detection of skin colors and a pixel chroma adaptive local processing,the algorithm produces more natural image look.The algorithm performance had been tested with an image quality judgment experiment of 20 persons.The experimental result indicates a better image preference. 相似文献