Design and Performance of a Novel Pancake Rogowski Coil for Measuring Pulse Currents

A novel pancake Rogowski coil without magnetic core is introduced in this paper. Owing to its special pancake winding structure, the coil is of low self-resistance and high self-inductance, and thus has excellent low frequency characteristic in the self-integral mode. Moreover, because of its unique installation method, the coil has a flexible sensitivity and can be applied under situations where toroidal air-core Rogowski coils or printed aircuit board （PCB） coils are not available. The parameters and performance of the pancake Rogowski coil are presented, and the principle of shielding is given. Measurements of step pulse current and oscillating pulse current by the coil are studied experimentally to illustrate its good linearity, reliable and flexible sensitivity and excellent frequency characteristic, especially its advantage in low frequency characteristic. The pancake Rogowski coil can be designed to assume round, square or rectangle shape, and has thus broad prospects in its application to the current measurement in such areas as plasma physics and pulsed power technology.

Pancake网络的t/k-诊断度及其算法

由于大型多处理机系统规模的不断扩大,其组件脆弱性也随之增加,因此故障容错性能对于多处理机系统尤为重要.t/k-诊断分析是一种能极大提高多处理机系统自我诊断性能的系统级故障诊断策略,该诊断策略能识别至多t个故障处理机节点,其中可能包含至多k个被误诊的处理机.首先给出了Pancake网络P_n(n≥5)的容错性分析,其后证明了P_n在PMC模型下是((k+1)n-3k-1)/k-可诊断的,其中1≤k≤3,最后还给出复杂度为O(NlogN)的快速诊断算法来识别所有的故障节点.

论PANCAKE互连网的连通性

本文详细地讨论了ｎ－Ｐａｎｃａｋｅ在删去不超过２ｎ—４个结点时的连通情况，并由此给出ｎ－Ｐａｎｃａｋｅ的条件连通度和条件直径。从本文可以看出，ｎ－Ｐａｎｃａｋｅ是一种具有很强连通性的较好的并行网络拓扑结构。

Quench characteristics and mechanical responses during quench propagation in rare earth barium copper oxide pancake coils

Quench and mechanical behaviors are critical issues in high temperature superconducting(HTS)coils.In this paper,the quench characteristics in the rare earth barium copper oxide(REBCO)pancake coil at 4.2K are analyzed,and a two-dimensional(2D)axisymmetric electro-magneto-thermal model is presented.The effects of the constituent materials,background field,and coil size are analyzed.An elastoplastic mechanical model is used to study the corresponding mechanical responses during the quench propagation.The variations of the temperature and strain in superconducting layers are compared.The results indicate that the radial strain evolutions can reflect the transverse quench propagation and the tensile hoop and radial stresses in superconducting layers increase with the quench propagation.The possible damages are discussed with the consideration of the effects of the background field and coil size.It is concluded that the high background field significantly increases the maximum tensile hoop and radial stresses in quenching coils and local damage may be caused.

Pancake冷却系统对宽平(16∶9)玻屏内曲率的影响

探讨了Pancake风机冷却系统对宽平(16:9)玻屏内曲率的影响。通过调整Pancake风机冷却风量来改善宽平(16:9)玻屏内曲率,拓宽了工艺调控思路,促进了技术进步。

Of Pigs, Princesses and Pancakes——Norwegian folk tales fascinate Chinese schoolchildren

It＇s all about determination and persistence against the odds, befieves Zhang Ke. ＂You can realize your dreams as long as you persist,＂ says the 11-year-old. ＂You see, if the youngest brother had run away like his elder brothers on that night, he would never have married the beautiful princess,＂ says the fifth-grader from Run＇an Public School in China＇s eastern Anhui Province.

Identification of the flavor profiles of Chinese pancakes from various areas using smart instruments combined with E-noses and E-tongues

In order to reveal the flavor characteristics of Chinese pancakes,the aroma and taste compounds of seven traditional Chinese pancakes were identified.The results showed that electronic nose(E-nose)analysis with PCA could successfully distinguish the aroma profiles of seven Chinese pancakes;the principal components PC1 and PC2 represented 75.74%and 23.2%of the total variance(98.94%)respectively.Meanwhile,the discrimination index of taste profiles of seven Chinese pancakes based on electronic tongue(E-tongue)analysis with LDA was 99.32%;the discriminant factors DF1 and DF2 represented 94.99%and 4.33%of the total variance respectively.Furthermore,GC-MS results demonstrated that thirty-threeflavor compounds were identified in seven Chinese pancakes,including aldehydes,alcohols,alkanes,acids,and aromatics.Among the flavor components,aldehydes with ROAVs higher than 1 contributed most significantly to the overall aroma,such as(E,E)-2,4-nonadienal present the largest contribution in Qingzhou pancake,Jinan and Yishui pancake;hexanal present the largest contribution in Shenxian and Gaomi pancake;nonanal and benzeneacetaldehyde present the largest contribution in Linqu and Tai’an pancake,respectively.The umami and sweet taste amino acids were the most abundant in all the Chinese pancake samples,and Qingzhou pancake had relatively high amino acid content.The content of glucose was higher than maltose in Gaomi,Shenxian,and Tai’an pancakes,whereas the content of maltose was higher than glucose in Linqu,Qingzhou,Jinan,and Yishui pancakes.These results indicated that the aroma and taste profiles of Chinese pancakes differed significantly in terms of their flavor compound composition.The presented results could be beneficial for providing a comprehensive method for flavor profile identification of traditional whole-grain-based staples such as Chinese pancakes.

Breaking the optical efficiency limit of virtual reality with a nonreciprocal polarization rotator

A catadioptric lens structure,also known as pancake lens,has been widely used in virtual reality(VR)displays to reduce the formfactor.However,the utilization of a half mirror(HM)to fold the optical path thrice leads to a significant optical loss.The theoretical maximum optical efficiency is merely 25%.To transcend this optical efficiency constraint while retaining the foldable characteristic inherent to traditional pancake optics,in this paper,we propose a theoretically lossless folded optical system to replace the HM with a nonreciprocal polarization rotator.In our feasibility demonstration experiment,we used a commercial Faraday rotator(FR)and reflective polarizers to replace the lossy HM.The theoretically predicted 100%efficiency can be achieved approximately by using two high-extinction-ratio reflective polarizers.In addition,we evaluated the ghost images using a micro-OLED panel in our imaging system.Indeed,the ghost images can be suppressed to undetectable level if the optics are with antireflection coating.Our novel pancake optical system holds great potential for revolutionizing next-generation VR displays with lightweight,compact formfactor,and low power consumption.

Mechanisms of the pancake vortex and vortex line movement in the high T_c superconductors Bi_2Sr_2CaCu_2O_8+δ and La_(1.93)Sr0.0_7CuO_4+δ

In the strict sense, it is not very clear why with magnetic field increasing, the normal-superconductive (NS) transition becomes broad for Bi2Sr2CaCu208+δ(Bi2212) while the NS transitions are almost parallel for La193Sroo7Cu04+δ(La214). In this paper, R-T relations are measured by the six-probe method. We propose a moving mechanism of the pancake vortex and vortex line for Bi2212. The theoretical curves fit the experiment data well.

Star网络S_5的Hamilton圈分解

最近Star网络和Pancake网络作为超立方体(并行计算机中多处理机互连的一种著名拓扑结构)的替代品而被许多作者研究.这两种网络的一个好的特点是:与超立方体相比较,它们有较小的直径和顶点度.尤其Star网络,更是受到研究人员的极大关注.在本文中:(a)我们提出了一种在这两种网络中找Hamilton圈的新方法.(b)证明了关于Star网络S_n的一个猜想在n=5时是正确的,即给出了S_5的两个边不交的Hamilton圈,且S_5是这两个Hamilton圈的并.

次解析集的正规嵌入

主要介绍了与长度度量等价的次解析度量--pancake度量,讨论了长度度量与正规嵌入的次解析集之间的关系,得出了关于长度度量的每个紧次解析集与正规嵌入的次解析集是bi-Lipschitz等价的,进而丰富了次解析集与bi-Lipschitz方向的研究成果.

Third generation high strength low alloy steels with improved toughness

On-line thermo mechanical controlled processing(TMCP) was conducted to develop the third generation high strength low alloy(HSLA) steel with high toughness economically.The ultra-low carbon content ensured a high level of upper shelf energy while ultrafine lath martensitic structure transformed from super-thin pancaked austenite during controlled rolling and cooling.The reduction of martensite block size decreased ductile-to-brittle transition temperature(DBTT) and compensated the strength loss due to carbon reduction.Consequently,the excellent balance of strength and toughness values was obtained as 950-1060 MPa for yield strength,180 J for Charpy V-notch impact absorbed energy at 30℃,which is much superior to that of traditional martensitic steel.Two mechanisms for the refinement of lath martensite block were proposed:One is the austenite grain refinement in the direction of thickness,and the other is the reduction in the fraction of sub-block boundaries with small misorientation and the increase in the fraction of block boundaries with large misorientation,possibly due to austenite hardening.

Ausforming effects on anisotropy of mechanical properties in HSLA martensitic steel

In order to clarify effects of prior pancaked austenitic structure on microstructure and mechanical properties of transformed martensite in ausformed steel,a super-thin pancaked austenite was processed by multi-pass rolling in a 0.03-2.6Mn0.06Nb-0.01Ti(wt%) low alloy steel.The evolution of prior pancaked austenite grain during multi-pass rolling was studied using Ni-30Fe model alloy.Related with the structure and texture in the prior super-thin pancaked austenite in Ni-30Fe alloy,the texture and anisotropy of mechanical properties of transformed martensite in the studied ausformed steel were focused on.There were mainly three kinds of rolling texture components in the super-thin pancaked austenite:Goss {110} 001,copper {112} 111 and brass {110} 112.They were further transformed into the weak {001} 110 and strong {112} 110,{111} 112 texture components in the martensitic structure.The orientation relationship(OR) of lath martensite transformation from pancaked austenite in the ausformed steel deviated larger from the exact Kurdjumov-Sachs(K-S) OR than in the case of equiaxed austenite without deformation.The tensile and yield strengths of the ausformed martensitic steel first decreased and then increased as the angle between tension direction and rolling direction increased.The main reason for the anisotropy of strength was considered as the texture component {112} 110 in martensite.However,the anisotropy of impact toughness was more complex and the main reasons for it are unknown.