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Characterization of Reverse Thermo-sensitive Genic Male Sterile Lines in Cold Regions of China
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作者 高扬 谭炎宁 +2 位作者 孟昭河 段美娟 徐秋生 《Agricultural Science & Technology》 CAS 2017年第7期1183-1186,1201,共5页
Yannong S, a reverse thermo-sensitive genic male sterile (TGMS) line, is sterile at high temperature and fertile at low temperature. In the present study, the fertility of Yannong S and the japonica reverse TGMS lin... Yannong S, a reverse thermo-sensitive genic male sterile (TGMS) line, is sterile at high temperature and fertile at low temperature. In the present study, the fertility of Yannong S and the japonica reverse TGMS lines derived from it was in- vestigated in Harbin, Heilongjiang from 2013 to 2015. The results showed that Yan- nong S was completely male sterile in July and August (the hottest months of the year in Harbin), and the seed setting rate of bagged panicles was 0. We also in- ferred that the critical temperature for inducing the sterility of Yannong S was higher than 28 ℃. Most of the japonica reverse TGMS lines derived from Yannong S were completely aborted in July and August, with a seed setting rate of 0. It can be con- cluded that the reverse TGMS lines derived from Yannong S are genetically stable lines that have a long period of sterility in cold regions, so they may be the ideal genetic materials for the development and in-situ seed production of japonica hybrid rice. 展开更多
关键词 Japonica hybrid rice Reverse thermo-sensitive genic male sterile lines Cold regions Yannong s FERTILITY
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Correlation Analysis on Male Sterile Lines Characters in Rapeseed(Brassica napus L.)
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作者 黄泽素 Laosuwan Paisan +4 位作者 Machikowa Thitiporn 陈泽辉 代文东 唐容 李德珍 《Agricultural Science & Technology》 CAS 2010年第9期183-187,共5页
[Objective] This study was conducted to evaluate the associations of many characters of male sterile lines in Brassica napus L.[Method]10 recessive genetic male sterile(RGMS)lines were used as parents to cross in a ... [Objective] This study was conducted to evaluate the associations of many characters of male sterile lines in Brassica napus L.[Method]10 recessive genetic male sterile(RGMS)lines were used as parents to cross in a half diallel cross method to produce 45 single cross hybrids.These 45 crosses and their 10 parents were evaluated at Guiyang during 2007-2008.[Result]The positive correlations of seed yield with plant height,pods per plant,days to flowering and days to maturity were significant.Their respective correlation coefficients(r)were 0.644,0.583,0.281 and 0.341.Highly significant and negative correlation was observed between seeds per pod and seed size(-0.533).Direct path coefficients were observed for pods per plant(0.556 2),seeds per pod(0.407 4),1 000-seed weight(0.481 3),and plant height(0.401 7)to seed yield.[Conclusion]Pods per plant,seeds per pod,1 000-seed weight and plant height were positive correlated with seed yield and showed high direct contributions to yield.Other characters including branches per plant,days to flowering,days to maturity and oil content had low contributions to seed yield. 展开更多
关键词 Brassica napus L. Male sterile line Correlation analysis characters
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Analysis on Combining Ability for Characters of Male Sterile Lines in Rapeseed(Brassica napus L.)
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作者 Huang Ze-su Laosuwan Paisan +4 位作者 Machikowa Thitipom Chen Ze-hui Dai Wen-dong Tang Rong Li De-zhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第3期28-37,共10页
The male sterile line is very important in the hybrid breeding program of rapeseed. This study was conducted to evaluate the combining ability of many characters of male sterile lines in Brassica napus L. Ten recessiv... The male sterile line is very important in the hybrid breeding program of rapeseed. This study was conducted to evaluate the combining ability of many characters of male sterile lines in Brassica napus L. Ten recessive genetic male sterile (RGMS) lines were used as parents to produce 45 single cross hybrids by using a half diallel cross method. These 45 crosses and their 10 parents were evaluated at Guiyang during 2007-2008. The results showed that both general combining ability (GCA) and specific combiing ability (SCA) effects were important for all characters, but additive gene effects were more predominant than non-additive gene effects. Qianyou 8AB and You 2894AB gave respective highly significant GCA effects of 230.94 and 127.65 kg-hm-2 for seed yield. Lines You 2894AB, QH303-4AB, You 157AB and You 2341AB gave highly significant GCA effects for oil content of 0.99, 1.62, 1.20 and 1.53%, respectively. The crosses among lines Qianyou 3AxQianyou 8B, Qianyou 8AxYou 2894B, You 2894AxQianyou 6B, Qianyou 8AxQH303-4B and Qianyou 8Ax Qianyou 6B gave high SCA effects of 616.29, 398.71,356.48, 394.24 and 303.79 kg hm-2 for seed yield, respectively. All these crosses also gave high seed yield indicating that these crosses could be used in the breeding program. 展开更多
关键词 Brassica napus L. male sterile line combining ability character
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CHARACTERISTIC IMPEDANCE OF SPECIFIC TRANSMISSION LINES WITH OFFSET INNER CONDUCTORS
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作者 马西奎 《Journal of Electronics(China)》 1990年第3期223-231,共9页
The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accu... The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accurate satisfaction of the boundary condition on theouter conductor.The combined method of the Gauss elimination and optimization is used tosolve the equation of charge simulation,and it is an effective method for increasing the accuracyand assuring the convergence.The Green’s functions of five transmission lines(i.e,with circular,elliptic,rectangular,trough and slab conductor)are given. 展开更多
关键词 Microwave TRANsMIssION line OFFsET and sPECIFIC CROss-sECTION TRANsMIssION line Green’s function Partial-charge-simulation Optimization
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Analysis and Simulation of the Influence of Electromagnetic Fields on Living Beings near HV Power Lines Using the FDTD Method
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作者 Anthony Bassesuka Sandoka Nzao 《Open Journal of Applied Sciences》 2023年第12期2343-2359,共17页
Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-freque... Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-frequency electromagnetic fields on the environment and which are capable of modifying and destroying our ecosystem. Particular interest was given in this article due to a massive influx of population living near high voltage lines. The analysis and simulation of the influence of low frequency electromagnetic fields on living beings in the vicinity of high voltage sources 132 kV and 220 kV in urban areas in DR Congo is the subject of our research with a view to estimating the level of exposure of humans to low frequency electromagnetic fields. To carry out our research, we used the classic method of analyzing the field produced near a high voltage line based on Maxwell’s image theory, the Maxwell-Gauss theorem and Maxwell-Ampère theorem to model and quantify low-frequency electromagnetic fields in the vicinity of high-voltage lines. The 2D FDTD numerical formulation was developed from telegraphers’ equations and allowed us to obtain models of current and voltage induced by electromagnetic fields on living beings below and near HV lines. The different simulations carried out on the proposed models illustrate the effects of the electrical and geometric parameters of the pylons on the distribution of the electromagnetic field in the vicinity of the HV lines. The results obtained were compared to the safety limits recommended by the standards. 展开更多
关键词 Low Frequency Electromagnetic Field Modeling Field and Health Maxwell’s Equations FDTD Method Electromagnetic Compatibility High Voltage line
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Studies on Breeding and Application of Thermo-sensitive Genie Male Sterile Line 402S in Brassica napus Ⅰ. Hie Breeding Procedure and Character of 402S 被引量:2
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作者 WuXianmeng XiDaiwen +1 位作者 NingZuliang DeangXixing 《Hunan Agricultural Science & Technology Newsletter》 2001年第3期12-15,共4页
A new rapeseed TGMS line 402S has been bred through six years with seven generations by hybridization and systematic breeding.402S possesses the similar thermo-sensitive male sterility to its female parent Xiangyou 91... A new rapeseed TGMS line 402S has been bred through six years with seven generations by hybridization and systematic breeding.402S possesses the similar thermo-sensitive male sterility to its female parent Xiangyou 91S which performed fertile,partially sterile and sterile throughout the flowering stage,and resembles its male parent Zhongshuang 4 on agronomic traits.And 402S has the double-low (low erutic acid and low glucosinolate) quality like its original parents. 展开更多
关键词 Brassica napus TGMs line 402s BREEDING character
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Establishment and characterization of a rat pancreatic stellate cell line by spontaneous immortalization 被引量:11
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作者 Atsushi Masamune Masahiro Satoh +2 位作者 Kazuhiro Kikuta Noriaki Suzuki Tooru Shimosegawa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第12期2751-2758,共8页
AIM: Activated pancreatic stellate cells (PSCs) have been implicated in the pathogenesis of pancreatic fibrosis and inflammation. Primary PSCs can be subcultured only several times because of their limited growth pote... AIM: Activated pancreatic stellate cells (PSCs) have been implicated in the pathogenesis of pancreatic fibrosis and inflammation. Primary PSCs can be subcultured only several times because of their limited growth potential. A continuous cell line may therefore be valuable in studying molecular mechanisms of these pancreatic disorders. The aim of this study was to establish a cell line of rat PSCs by spontaneous immortalization.METHODS: PSCs were isolated from the pancreas of male Wistar rats, and conventional subcultivation was performed repeatedly. Telomerase activity was measured using the telomere repeat amplification protocol. Activation of transcription factors was assessed by electrophoretic mobility shift assay.Activation of mitogen-activated protein (MAP) kinases was examined by Western blotting using anti-phosphospecific antibodies. Expression of cytokine-induced neutrophil chemoattractant-1 was determined by enzyme immunoassay.RESULTS: Conventional subcultivation yielded actively growing cells. One clone was obtained after limiting dilution,and designated as SIPS. This cell line has been passaged repeatedly more than 2 years, and is thus likely immortalized.SIPS cells retained morphological characteristics of primary,culture-activated PSCs. SIPS expressed α-smooth muscle actin, glial acidic fibrillary protein, vimentin, desmin, type Ⅰ collagen, fibronectin, and prolyl hydroxylases. Telomerase activity and p53 expression were negative. Proliferation of SIPS cells was serum-dependent, and stimulated with platelet-derived growth factor-BB through the activation of extracellular signal-regulated kinase. Interleukin-1β activated nuclear factor-κB, activator protein-1, and MAP kinases.Interleukin-1β induced cytokine-induced neutrophil chemoattractant-1 expression through the activation of nuclear factor-κB and MAP kinases.CONCLUSION: SIPS cells can be useful for in vitro studies of cell biology and signal transduction of PSCs. 展开更多
关键词 Animals Base sequence Cell Culture Techniques Cell line Transformed Cells Cultured Cystic Fibrosis Cytoskeletal Proteins Extracellular Matrix Proteins IMMUNOHIsTOCHEMIsTRY NF-kappa B Oligonucleotide Probes PANCREAs Rats Research support Non-U.s. Gov't Transcription Factor AP-1
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Analysis on Characters and Application Potential of a Sorghum Sterile Line ‘Ji2055A’
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作者 Jihong LI Bingxu CHEN Shijie GAO 《Agricultural Biotechnology》 CAS 2012年第5期14-17,共4页
' Ji2055A' is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rat... ' Ji2055A' is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rate of 100%, ' Ji2055A' has a stable male sterility and highly viable stignms. Selfing won't lead to seeds, This sterile line is strongly resistant to drought and lodging in addition to resistance to leaf spot and head smut. Generally, it has a yield of 3 000 -4 000 kg/hm2 and the hybrid seed yield is between 4 000 - 5 000 kg/hm2, with a high combining ability. There are six varieties approved by the state and the province, as well as another eight new combines under regional testing. The obtained hybrids are strongly resistant, widely adaptable with a great potential to increase yield, ' Ji2055A' has promoted the breeding and production of spring early maturing sorghum in China. 展开更多
关键词 sORGHUM sterile line Ji2055A' characters APPLICATION
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Offline Arabic character recognition system
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作者 黄建华 唐降龙 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期80-88,共9页
Several languages use the Arabic alphabets and Arabic scripts present challenges because the letter shape is context sensitive. For the past three decades, there has been a mounting interest among researchers in this ... Several languages use the Arabic alphabets and Arabic scripts present challenges because the letter shape is context sensitive. For the past three decades, there has been a mounting interest among researchers in this problem. In this paper we present an Arabic Character Recognition system and review the theory behind the Arabic recognition system, the characteristics of Arabic writing, the sequence steps of recognizing Arabic text. These steps are separately discussed, and previous research work on each step is reviewed. Also in this paper we give some samples of Arabic fonts. 展开更多
关键词 RECOGNITION off line Arabic character
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Data Pre-processing and Stroke Segment Extraction for On-line Handwritten Chinese Character Recognition
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作者 唐降龙 舒文豪 +1 位作者 刘家锋 李铁才 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期76-81,共6页
The stroke segments:' are proposed to be used as the basic features for handwritten Chinese character recognition. In this way, it is possible to overcome the difFiculties of unstable stroke information caused by ... The stroke segments:' are proposed to be used as the basic features for handwritten Chinese character recognition. In this way, it is possible to overcome the difFiculties of unstable stroke information caused by stroke Joinings. The techniques of data pre-processing and stroke segment extraction have been described. In extracting stroke segment, not only the characteristics of the stroke itself, but also its absolute positions as well as relative positions with other strokes in the character have been taken into account.The primitive features for recognition were extracted under these comprehensive considerations. 展开更多
关键词 ss: ON-line CHINEsE character RECOGNITION sEGMENT EXTRACTION
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The Women Characters of the 1930s in the Chinese TV Serials
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作者 周时娥 张雯 《海外英语》 2011年第13期278-280,共3页
The women of the 1930s in the Chinese TV serials deduct inspiring stories.They play different roles in the big wealthy families such as mothers-in-law,daughters-in-law,and maidservants.There are unceasing conflicts be... The women of the 1930s in the Chinese TV serials deduct inspiring stories.They play different roles in the big wealthy families such as mothers-in-law,daughters-in-law,and maidservants.There are unceasing conflicts between these women,because of their struggle for men's love,wealth or social position.The theme of their stories is always about fertility,love,kindness and evil,with the ending being either comic or tragic.The stories of various kinds of women of the 1930s in the Chinese TV serials decorate and enrich the lives of many of us latecomers and their names are passed on from generation to generation. 展开更多
关键词 WOMEN characters 1930s TV sERIALs
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S Zorb装置反应器接收器脱气线和再生器取热盘管改造
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作者 张伟 《炼油技术与工程》 CAS 2024年第5期29-32,共4页
某公司对S Zorb装置首个运行周期内出现的反应器接收器脱气线泄漏、再生器取热盘管泄漏等运行问题开展了技术攻关,提出了工艺优化调整、工程技术改造建议。2019年大检修时对反应器脱气线进行扩径,由DN100扩径为DN150,控制气提量小于670 ... 某公司对S Zorb装置首个运行周期内出现的反应器接收器脱气线泄漏、再生器取热盘管泄漏等运行问题开展了技术攻关,提出了工艺优化调整、工程技术改造建议。2019年大检修时对反应器脱气线进行扩径,由DN100扩径为DN150,控制气提量小于670 m^(3)/h,对再生系统取热蒸汽和再生风流控阀等进行了工程技术改造。第二运行周期未出现脱气线减薄泄漏和再生器取热盘管泄漏问题。2023年6月大检修时对上次大检修改造部位进行检查以验证工程改造的有效性,经全面检查,确认脱气线内部未发现冲刷痕迹,再生器取热盘管打压合格,外观正常,证明改造措施有效,可以满足“四年一修”目标要求。 展开更多
关键词 s Zorb装置 反应器接收器 脱气线 再生器 取热盘管 泄漏 冲刷腐蚀 高频振荡
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Vehicle License Plate Character Segmentation 被引量:6
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作者 Mei-Sen Pan Jun-Biao Yan Zheng-Hong Xiao 《International Journal of Automation and computing》 EI 2008年第4期425-432,共8页
Vehicle license plate (VLP) character segmentation is an important part of the vehicle license plate recognition system (VLPRS).This paper proposes a least square method (LSM) to treat horizontal tilt and vertical til... Vehicle license plate (VLP) character segmentation is an important part of the vehicle license plate recognition system (VLPRS).This paper proposes a least square method (LSM) to treat horizontal tilt and vertical tilt in VLP images.Auxiliary lines are added into the image (or the tilt-corrected image) to make the separated parts of each Chinese character to be an interconnected region.The noise regions will be eliminated after two fusing images are merged according to the minimum principle of gray values. Then,the characters are segmented by projection method (PM) and the final character images are obtained.The experimental results show that this method features fast processing and good performance in segmentation. 展开更多
关键词 Vehicle license plate (VLP) least square method (LsM) auxiliary lines character segmentation pixel.
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Lytic Characteristics and Identification of Two Alga-lysing Bacterial Strains 被引量:4
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作者 PEI Haiyan HU Wenrong 《Journal of Ocean University of China》 SCIE CAS 2006年第4期368-374,共7页
All previously reported bacterial species which are capable of lysing harmful algae have been isolated from coastal environments in which harmful algae blooms have occurred. Due to the low concentration of alga-lysing... All previously reported bacterial species which are capable of lysing harmful algae have been isolated from coastal environments in which harmful algae blooms have occurred. Due to the low concentration of alga-lysing bacteria in an algal bloom, it is difficult to isolate the alga-lysing bacteria by existing methods. In this paper, two algae-lysing bacterial strains, P01 and P03, have been isolated from a biosystem immobilized on a sponge that was highly effective in removing algae and microcystins. Their lysing modes and effects on Microcystis aeruginosa have been studied. The results show that the degradation processes of these two strains for M. aeruginosa accorded with a first-order reaction model when the chlorophylla concentration was in the range from 0 to 1000 μgL-1. The degradation rate constants were 0.1067, 0.1274 and 0.2792 for P01 and0.0683, 0.0744 and 0.028 97 for P03, when the bacterial densities were 8.6 × 105, 8.6 × 106 and 8.6 × 107cells mL-1 respectively. Moreover, the two bacterial strains had favourable lytic effects not only on M. aeruginosa , but also on Chlorella and Scene-desmus. Their lytic effect on M. aeruginosa did not require physical cell to cell contact, but proceeded by the production of an extracellular product. The bacterial strains were identified as Bacillus species by PCR amplification of the 16S rRNA gene, BLAST analysis, and comparison with sequences in the GenBank nucleotide database. 展开更多
关键词 alga-lysing bacteria lytic character 16s rDNA BACILLUs
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Numerical Modeling and Computer Simulation of a Meander Line Antenna for Alzheimer’s Disease Treatment, a Feasibility Study
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作者 Felipe P. Perez Maryam Rahmani +8 位作者 Jorge Morisaki Farhan Amran Syazwani Bakri Akmal Halim Alston Dsouza Nurafifi Mohd Yusuff Amran Farhan James Maulucci Maher Rizkalla 《Journal of Biosciences and Medicines》 CAS 2023年第2期177-185,共9页
Alzheimer’s disease (AD) is a brain disorder that eventually causes memory loss and the ability to perform simple cognitive functions;research efforts within pharmaceuticals and other medical treatments have minimal ... Alzheimer’s disease (AD) is a brain disorder that eventually causes memory loss and the ability to perform simple cognitive functions;research efforts within pharmaceuticals and other medical treatments have minimal impact on the disease. Our preliminary biological studies showed that Repeated Electromagnetic Field Stimulation (REFMS) applying an EM frequency of 64 MHz and a specific absorption rate (SAR) of 0.4 - 0.9 W/kg decrease the level of amyloid-β peptides (Aβ), which is the most likely etiology of AD. This study emphasizes uniform E/H field and SAR distribution with adequate penetration depth penetration through multiple human head layers driven with low input power for safety treatments. In this work, we performed numerical modeling and computer simulations of a portable Meander Line antenna (MLA) to achieve the required EMF parameters to treat AD. The MLA device features a low cost, small size, wide bandwidth, and the ability to integrate into a portable system. This study utilized a High-Frequency Simulation System (HFSS) in the design of the MLA with the desired characteristics suited for AD treatment in humans. The team designed a 24-turn antenna with a 60 cm length and 25 cm width and achieved the required resonant frequency of 64 MHz. Here we used two numerical human head phantoms to test the antenna, the MIDA and spherical head phantom with six and seven tissue layers, respectively. The antenna was fed from a 50-Watt input source to obtain the SAR of 0.6 W/kg requirement in the center of the simulated brain tissue layer. We found that the E/H field and SAR distribution produced was not homogeneous;there were areas of high SAR values close to the antenna transmitter, also areas of low SAR value far away from the antenna. This paper details the antenna parameters, the scattering parameters response, the efficiency response, and the E and H field distribution;we presented the computer simulation results and discussed future work for a practical model. 展开更多
关键词 Alzheimer’s Disease Meander line Antenna HFss EMF linearity sAR Field Distribution
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Critical Analysis on Characters of Pearl S.Buck' the Good Earth
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作者 韩娇阳 王可可 潘晓燕 《海外英语》 2013年第8X期213-216,共4页
Since the publication of the Good Earth in 1922, Pearl S, Buck published another two novels based on the same theme and they were called the House of Earth Trilogy. The House of Earth Trilogy used as a window to under... Since the publication of the Good Earth in 1922, Pearl S, Buck published another two novels based on the same theme and they were called the House of Earth Trilogy. The House of Earth Trilogy used as a window to understand China for the westerners at that time. And it had a great impact on the whole world. People gave two different views on her success of winning so many awards. Some thought that she wrote what she knew and her works were based on her own experiences. But others said that she was a foreigner and her values, her distinct aesthetic views would affect her writing. So, some of her depictions, to some extent, were untruthful and distorted. The aim of writing this thesis is to give an objective judgment on the Good Earth, and make it easier for us to communicate with the westerners on literature. 展开更多
关键词 the GOOD EARTH PEARL s. BUCK characters’Perspectiv
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General Analytic Solution of the Telegrapher’s Equations and the Resulting Consequences for Electrically Short Transmission Lines 被引量:1
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作者 Steffen Kü hn 《Journal of Electromagnetic Analysis and Applications》 2020年第6期71-87,共17页
Based on classical circuit theory, this article develops a general analytic solution of the telegrapher’s equations, in which the length of the cable is explicitly contained as a freely adjustable parameter. For this... Based on classical circuit theory, this article develops a general analytic solution of the telegrapher’s equations, in which the length of the cable is explicitly contained as a freely adjustable parameter. For this reason, the solution is also applicable to electrically short cables. Such a model has become indispensable because a few months ago, it was experimentally shown that voltage fluctuations in ordinary but electrically short copper lines move at signal velocities that are significantly higher than the speed of light in a vacuum. This finding contradicts the statements of the special theory of relativity but not, as is shown here, the fundamental principles of electrical engineering. Based on the general transfer function of a transmission line, the article shows mathematically that an unterminated, electrically short cable has the characteristics of an ideal delay element, meaning that an input signal appears at the output with a slight delay but remains otherwise unchanged. Even for conventional cables, the time constants can be so small that the corresponding signal velocities can significantly exceed the speed of light in a vacuum. The article also analyses the technical means with which this effect can be conveyed to very long cables. 展开更多
关键词 Telegrapher’s Equations Transmission line Theory special Theory of Relativity Electrically short Transmission lines FTL Communication
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基于YOLOv5s的轻量化架空输电线路鸟巢检测网络
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作者 徐业东 蔡亚恒 +2 位作者 李严 刘学雷 曹英丽 《电子测量技术》 北大核心 2024年第7期138-148,共11页
架空输电线路上的鸟巢侵占会对铁塔上的电力设备造成安全隐患,间接可能影响整个电力系统的稳定运行。针对目前架空输电线路鸟巢检测模型在复杂场景以及小目标场景下检测精度不高,检测效率低,模型复杂等问题。本研究提出一种基于YOLOv5s... 架空输电线路上的鸟巢侵占会对铁塔上的电力设备造成安全隐患,间接可能影响整个电力系统的稳定运行。针对目前架空输电线路鸟巢检测模型在复杂场景以及小目标场景下检测精度不高,检测效率低,模型复杂等问题。本研究提出一种基于YOLOv5s框架的轻量化架空输电线路鸟巢检测网络。首先在主干部分采用Fasternet重构YOLOv5s特征提取网络,降低模型复杂度,提高运行速度;然后在特征融合网络部分嵌入ConvMixer层,ConvMixer层的结构设计有助于在特征信息中更好的捕捉空间和通道的关系,提升模型对于小目标的检测能力;最后在特征融合网络部分引入ODConv模块,令送入检测头的特征图包含更多有效特征,提高模型对复杂场景和小目标的检测性能。实验结果表明,本文与基线模型YOLOv5s相比,计算量和模型体积分别减少了86%和72%,平均精度均值达到96.4%,检测速度达到104.2帧/s,验证了本文改进模型的有效性和可行性。 展开更多
关键词 轻量化 架空输电线路 YOLOv5s 鸟巢 目标检测
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基于TDLAS的H_(2)S高温反应特性实验研究
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作者 王嘉琦 田思迪 +3 位作者 高东波 田志伟 彭志敏 杜艳君 《热力发电》 CAS CSCD 北大核心 2024年第2期162-169,共8页
电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectrosc... 电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectroscopy,TDLAS)方法结合多通池和计算机搭建低气体摩尔分数在线测量系统,实现了对混合气体中摩尔分数在10–6量级H_(2)S的精确在线测量,并利用该测量系统进行了H_(2)S高温反应实验,探究实验温度和混合气体中O_(2)摩尔分数对该反应的影响。实验结果展示了压力为80 kPa、O_(2)摩尔分数为0~5%的条件下,H_(2)S开始发生化学反应的温度随O_(2)摩尔分数变化的变化规律,整体而言,混合气体中O_(2)摩尔分数越高,H_(2)S开始发生化学反应的温度越低。实验结果可以为锅炉烟气中H_(2)S的生成、转化和危害控制提供一定数据基础。 展开更多
关键词 TDLAs H_(2)s 在线测量 高温反应 O_(2)摩尔分数
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基于改进HybridNets的多任务驾驶感知方法
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作者 武鹏宇 张远辉 刘康 《激光杂志》 CAS 北大核心 2024年第10期80-85,共6页
针对计算资源有限的自动驾驶系统和多任务驾驶感知算法精度低问题,提出了一种改进的HybridNets多任务驾驶感知算法。选择EfficientNetV2-S作为该算法的主干网络,降低参数数量,提高训练速度和识别准确率;结合深度可分离卷积并采用shuffle... 针对计算资源有限的自动驾驶系统和多任务驾驶感知算法精度低问题,提出了一种改进的HybridNets多任务驾驶感知算法。选择EfficientNetV2-S作为该算法的主干网络,降低参数数量,提高训练速度和识别准确率;结合深度可分离卷积并采用shuffle-channel方式卷积降低模型计算量;使用三个独立的解码器来解决不同难度的问题,并在主干网络与Neck端之间加入A2-Nets双重注意力机块,充分提取全局特征。与基础网络HybridNets相比,该模型在车辆检测任务中mAP50可达79.8%,提高了2.6%;可行驶区域分割任务中mIoU可达91.8%,提高了1.2%;车道线检测任务中IoU可达32.55%,提高了0.93%。运行速度达到38 FPS。实验结果表明,与现有方法相比,所提方法的准确率有较大提高。 展开更多
关键词 EfficientNetV2-s A2-Nets 目标检测 驾驶区域分割 车道线检测
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