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Journal of Animal Science and Biotechnology 2024年第1期15卷 396-411页

作者： Shengyang Xu chong jiao Qiyu Diao Yan Tu Beijing Key Laboratory for Dairy Cow Nutrition Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081People’s Republic of China

Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and *** study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different *** calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host *** During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this ***,no significant differences were observed in rumen fermentation parameters and serum indices between the two *** The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves.

关键词： Average daily gain Calves Preweaning period Rumen microbiota

Burn image segmentation based on Mask Regions with Convolutional Neural Network deep learning framework:more accurate and more convenient

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Burns & Trauma 2019年第1期7卷 44-57页

作者： chong jiao Kehua Su Weiguo Xie Ziqing Ye School of Computer Science Wuhan UniversityWuhan 430072China Institute of Burns Wuhan Hospital No.3 and Tongren Hospital of Wuhan UniversityWuhan 430060China

Background:Burns are life-threatening with high morbidity and *** diagnosis supported by accurate burn area and depth assessment is critical to the success of the treatment decision and,in some cases,can save the patient’s *** techniques such as straight-ruler method,aseptic film trimming method,and digital camera photography method are not repeatable and comparable,which lead to a great difference in the judgment of burn wounds and impede the establishment of the same evaluation ***,in order to semi-automate the burn diagnosis process,reduce the impact of human error,and improve the accuracy of burn diagnosis,we include the deep learning technology into the diagnosis of ***:This article proposes a novel method employing a state-of-the-art deep learning technique to segment the burn wounds in the *** designed this deep learning segmentation framework based on the Mask Regions with Convolutional Neural Network(Mask R-CNN).For training our framework,we labeled 1150 pictures with the format of the Common Objects in Context(COCO)data set and trained our model on 1000 *** the evaluation,we compared the different backbone networks in our *** backbone networks are Residual Network-101 with Atrous Convolution in Feature Pyramid Network(R101FA),Residual Network-101 with Atrous Convolution(R101A),and InceptionV2-Residual Network with Atrous Convolution(IV2RA).Finally,we used the Dice coefficient(DC)value to assess the model ***:The R101FA backbone network gains the highest accuracy 84.51%in 150 ***,we chose different burn depth pictures to evaluate these three backbone *** R101FA backbone network gains the best segmentation effect in superficial,superficial thickness,and deep partial *** R101A backbone network gains the best segmentation effect in full-thickness ***:This deep learning framework shows excellent segmentation in burn wound and extremely

关键词： Burn image Deep learning Mask R-CNN Image segmentation

Reciprocity principle-based model for shielding effectiveness prediction of a rectangular cavity with a covered aperture

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Chinese Physics B 2015年第10期24卷 166-171页

作者：焦重庆李月月 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

According to the reciprocity principle, we propose an efficient model to compute the shielding effectiveness of a rectangular cavity with apertures covered by conductive sheet against an external incident electromagnetic wave. This problem is converted into another problem of solving the electromagnetic field leakage from the cavity when the cavity is excited by an electric dipole placed within it. By the combination of the unperturbed cavity field and the transfer impedance of the sheet, the tangential electric field distribution on the outer surface of the sheet is obtained. Then, the field distribution is regarded as an equivalent surface magnetic current source responsible for the leakage field. The validation of this model is verified by a comparison with the circuital model and the full-wave simulations. This time-saving model can deal with arbitrary aperture shape, various wave propagation and polarization directions, and the near-field effect.

关键词： electromagnetic shielding electromagnetic leakage apertured cavity conductive material

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有损金属圆波导中电磁波传输特性的研究

物理学报 2006年第12期55卷 6360-6367页

作者：焦重庆罗积润中国科学院电子学研究所

基于电磁模式的色散方程,研究了有损金属圆波导中电磁模式的传输问题.在考虑了损耗层厚度影响的情况下,得到了各模式传输常数的近似解析表达式,此式适用于截止频率附近.通过解析表达式和波导模式色散方程,对衰减常数和相位常数进行了大... 详细信息

基于电磁模式的色散方程,研究了有损金属圆波导中电磁模式的传输问题.在考虑了损耗层厚度影响的情况下,得到了各模式传输常数的近似解析表达式,此式适用于截止频率附近.通过解析表达式和波导模式色散方程,对衰减常数和相位常数进行了大量数值计算,得到了它们随损耗层厚度、频率以及损耗层电导率的变化规律,两种方法所获得的结果有较好的一致性.研究表明,损耗强度和损耗层厚度的变化会改变波导中电磁模式的色散和简并特性,对于改善高功率回旋行波放大器中注波互作用带宽和模式竞争非常有益.

关键词：有损圆波导相位常数衰减常数色散方程

中等导电性材料覆盖的金属腔体的电磁屏蔽效能研究

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物理学报 2013年第21期62卷 134-139页

作者：牛帅焦重庆李琳华北电力大学新能源电力系统国家重点实验室北京102206

基于传输线和波导理论,提出了一种用于计算覆盖中等导电性材料的金属腔体电磁屏蔽效能的解析理论模型,并通过和全波电磁模拟结果的比较检验了该模型的有效性.计算分析了屏蔽体屏蔽效能的位置效应和谐振效应.建议了一种评价导电材料电磁... 详细信息

基于传输线和波导理论,提出了一种用于计算覆盖中等导电性材料的金属腔体电磁屏蔽效能的解析理论模型,并通过和全波电磁模拟结果的比较检验了该模型的有效性.计算分析了屏蔽体屏蔽效能的位置效应和谐振效应.建议了一种评价导电材料电磁屏蔽效能的方法,能很好的削弱谐振效应和位置效应的影响,直接反映出材料本身的电磁屏蔽效能.

关键词：电磁屏蔽导电材料金属腔体屏蔽效能

一种三段式互作用结构谐波倍增回旋行波放大器互作用电路的模拟

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电子与信息学报 2007年第8期29卷 2009-2013页

作者：焦重庆罗积润中科院电子学研究所

该文给出了一种三段式互作用结构谐波倍增回旋行波管放大器互作用电路的理论设计过程。利用线性理论研究竞争模式的起振条件,选取保证工作模式稳定的工作参数。利用自洽非线性理论研究其饱和输出性能。计算表明,在100kV,25A,速度比1.0... 详细信息

该文给出了一种三段式互作用结构谐波倍增回旋行波管放大器互作用电路的理论设计过程。利用线性理论研究竞争模式的起振条件,选取保证工作模式稳定的工作参数。利用自洽非线性理论研究其饱和输出性能。计算表明,在100kV,25A,速度比1.0以及速度零散5%的电子注推动下,在34.6GHz频率可获得饱和输出功率540kW,效率21.6%,增益58dB和约4.5%的3dB带宽。

关键词：回旋行波管谐波倍增 Ka波段注波互作用

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开孔矩形腔体电磁泄漏特性的解析研究

物理学报 2014年第21期63卷 95-101页

作者：焦重庆李月月华北电力大学新能源电力系统国家重点实验室北京102206

本文提出了一种用于计算开孔矩形腔体电磁泄漏场的解析理论模型.该理论模型先基于模式展开法求解封闭腔场,进而依据Bethe小孔耦合理论将泄漏场与封闭腔场用等效偶极子关联.该模型可以考虑波频率、场源位置、开孔位置及场强观测点位置等... 详细信息

本文提出了一种用于计算开孔矩形腔体电磁泄漏场的解析理论模型.该理论模型先基于模式展开法求解封闭腔场,进而依据Bethe小孔耦合理论将泄漏场与封闭腔场用等效偶极子关联.该模型可以考虑波频率、场源位置、开孔位置及场强观测点位置等因素的影响,计算结果与全波仿真结果一致.本文计算分析了相关因素对电磁屏蔽效能的影响规律,并给出了物理解释.结果表明近场屏蔽效能小于远场屏蔽效能,且近场区电场屏蔽效能与磁场屏蔽效能并不相同.

关键词：电磁泄漏电磁屏蔽小孔耦合矩形腔体

A Brief Analysis of Atticus Finch's Personality in To Kill A Mockingbird

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海外英语 2019年第8期 215-219页

作者：焦崇云南农业大学外语学院

Harper Lee’s To Kill A Mockingbird has always been considered as one of the classic literary works in *** published,this novel won the Pulitzer Prize for Fiction and its author Harper Lee became one of the most popular *** researches and articles by foreign and domestic scholars had been *** paper is based on the previous studies,and discusses about the personality of Atticus *** whole passage is divided into three *** one gives a brief introduction of Harper Lee and the background information of this novel,as well as the work’s *** two analyzes the main character Atticus Finch’s personality,and presents his different characters when facing different people and in different *** three explores Atticus Finch’s impact on people in To Kill A Mockingbird and its *** conclusion,by analyzing the personality of the main characters,we could have a more comprehensive view of the development of the story and a better understanding of the novel.

关键词： Atticus Finch kind integrity

Resonance suppression and electromagnetic shielding effectiveness improvement of an apertured rectangular cavity by using wall losses

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Chinese Physics B 2013年第8期22卷 404-409页

作者：焦重庆朱弘钊 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

The cavity-mode resonance effect could result in significant degradation of the shielding effectiveness （SE） of a shielding enclosure around its resonance frequencies. In this paper, the influence of coated wall loss on the suppression of the resonance effect is investigated. For this purpose, an equivalent circuit model is employed to analyze the SE of an apertured rectangular cavity coated with an inside layer of resistive material. The model is developed by extending Robinson＇s equivalent circuit model through incorporating the effect of the wall loss into both the propagation constant and the characteristic impedance of the waveguide. Calculation results show that the wall loss could lead to great improvement on the SE for frequencies near the resonance but almost no effect on the SE for frequencies far away from the resonance.

关键词： electromagnetic shielding rectangular cavity wall losses resonance effect

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TE_(21)模回旋返波振荡的起振分析

电子与信息学报 2010年第2期32卷 459-463页

作者：张涛焦重庆罗积润中国科学院电子学研究所北京100190 中国科学院研究生院北京100039 华北电力大学高电压与电磁兼容北京市重点实验室北京102206

该文基于回旋行波放大器的线性理论,对TE21模回旋返波振荡起振长度和起振频率随导引中心半径、电压、速度比、注电流及工作磁场等参数的变化进行了详细的数值模拟,并给出了相应的物理解释,分析了TE21模基波和二次谐波回旋返波振荡特点,... 详细信息

该文基于回旋行波放大器的线性理论,对TE21模回旋返波振荡起振长度和起振频率随导引中心半径、电压、速度比、注电流及工作磁场等参数的变化进行了详细的数值模拟,并给出了相应的物理解释,分析了TE21模基波和二次谐波回旋返波振荡特点,研究了分布损耗对回旋返波振荡的抑制效果。所得结果对回旋行波放大器和回旋返波振荡器的设计有参考意义。

关键词：回旋行波放大器回旋返波振荡起振条件分布损耗