检索结果-南通市图书馆

Iterative photonic processor for fast complexvalued matrix inversion

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2022年第11期10卷 2488-2501页

作者： MINJIA CHEN qixiang cheng MASAFUMI AYATA MARK HOLM RICHARD PENTY Department of Engineering Centre for Photonic SystemsElectrical Engineering DivisionUniversity of CambridgeCambridge CB30FAUK Huawei Technologies(Sweden)AB 16440 KistaSweden

An N×N iterative photonic processor is proposed for the first time, we believe, for fast computation of complexvalued matrix inversion, a fundamental but computationally expensive linear algebra operation. Compared to traditional digital electronic processing, optical signal processing has a few unparalleled features that could enable higher representational efficiency and faster computing speed. The proposed processor is based on photonic integration platforms–the inclusion of Ⅲ-V gain blocks offers net neutral loss in the phase-sensitive loops. This is essential for the Richardson iteration method that is adopted in this paper for complex linear systems. Wavelength multiplexing can be used to significantly improve the processing efficiency, allowing the computation of multiple columns of the inverse matrix using a single processor core. Performances of the key building blocks are modeled and simulated, followed by a system-level analysis, which serves as a guideline for designing an N×N Richardson iteration processor. An inversion accuracy of>98%can be predicted for a 64×64 photonic processor with a>80times faster inversion rate than electronic processors. Including the power consumed by both active components and electronic circuits, the power efficiency of the proposed processor is estimated to be over an order of magnitude more energy-efficient than electronic processors. The proposed iterative photonic integrated processor provides a promising solution for future optical signal processing systems.

关键词： valued matrix iteration

Harnessing self-heating effect for ultralow-crosstalk electro-optic Mach–Zehnder switches

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2023年第10期11卷 1757-1769页

作者： PENG BAO qixiang cheng JINLONG WEI GIUSEPPE TALLI MAXIM KUSCHNEROV RICHARD V.PENTY Centre for Photonic Systems Electrical Engineering DivisionDepartment of EngineeringUniversity of CambridgeCambridge CB30FAUK Huawei Technologies Duesseldolf GmbH European Research Center80992 MunichGemany Current address:Peng cheng Laboratory Shenzhen 518000China

This paper presents a novel approach to counterbalance free-carrier-absorption(FCA) in electro-optic(E-O)Mach–Zehnder interferometer(MZI) cells by harnessing the self-heating effect. We show insights on crosstalk limitations in MZIs with direct carrier-injection and provide a detailed design methodology on a differential phase shifter pair. Leveraging both free-carrier dispersion(FCD) and self-heating effects, our design enables arbitrary phase tuning with balanced FCA loss in the pair of arms, eliminating the need for additional phase corrections and creating ultralow crosstalk MZI elements. This neat design disengages from the commonly used nested structure, thus providing an opportunity of embedding tunable couplers for correcting imperfect splitting ratios given that only two are needed. We show that with the use of tunable directional couplers, a standard±10 nm process variation is tolerated, while achieving a crosstalk ratio below-40 dB. By direct carrier injection in both arms, the proposed device operates at nanosecond scales and can bring about a breakthrough in the scalability of E-O switch fabrics, as well as other silicon integrated circuits that have stringent requirements for crosstalk leakage.

关键词： crosstalk interferometer breakthrough

Advances in cost-effective integrated spectrometers

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2022年第7期11卷 1379-1396页

作者： Ang Li Chunhui Yao Junfei Xia Huijie Wang qixiang cheng Richard Penty Yeshaiahu Fainman Shilong Pan Key Laboratory of Radar Imaging and Microwave Photonics Ministry of EducationNanjing University of Aeronautics and AstronauticsNanjing 210016China Litin Technology XuzhouJiangsuChina Department of Engineering University of Cambridge9 JJ Thomson AvenueCambridge CB30FAUK Colllege of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Electrical and Computer Engineering University of California at San DiegoLa JollaCAUSA

The proliferation of Internet-of-Things has promoted a wide variety of emerging applications that require compact,lightweight,and low-cost optical *** substantial progresses have been made in the miniaturization of spectrometers,most of them are with a major focus on the technical side but tend to feature a lower technology readiness level for *** importantly,in spite of the advancement in miniaturized spectrometers,their performance and the metrics of real-life applications have seldomly been connected but are highly *** review paper shows the market trend for chip-scale spectrometers and analyzes the key metrics that are required to adopt miniaturized spectrometers in real-life *** progress addressing the challenges of miniaturization of spectrometers is summarized,paying a special attention to the CMOS-compatible fabrication platform that shows a clear pathway to massive *** for ways forward are also presented.

关键词： cost summarized spite

Broadband picometer-scale resolution on-chip spectrometer with reconfigurable photonics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2023年第7期12卷 1415-1424页

作者： Chunhui Yao Minja Chen Ting Yan Liang Ming qixiang cheng Richard Penty Centre for Photonic Systems Electrical Engineering DivisionDepartment of EngineeringUniversity of CambridgeCambridge CB3 OFAUK GlitterinTech Limited Xuzhou 221000China

Miniaturization of optical spectrometers is important to enable spectroscopic analysis to play a role in in situ,or even in vitro and in vivo characterization ***,scaled-down spectrometers generally exhibit a strong trade-off between spectral resolution and operating bandwidth,and are often engineered to identify signature spectral peaks only for specific *** this paper,we propose and demonstrate a novel global sampling strategy with distributed filters for generating ultra-broadband pseudo-random spectral *** geometry of all-pass ring filters is tailored to ensure small self-and cross-correlation for effective information acquisition across the whole spectrum,which dramatically reduces the requirement on sampling *** employ the power of reconfigurable photonics in spectrum shaping by embedding the engineered distributed *** a moderate mesh of MZls,we create 256 diverse spectral responses on a single chip and demonstrate a resolution of 20 pm for single spectral lines and 30 pm for dual spectral lines over a broad bandwidth of 115 nm,to the best of our knowledge achieving a new record of bandwidth-to-resolution *** simulations reveal that this design will readily be able to achieve single-picometer-scale *** further show that the reconfigurable photonics provides an extra degree of programmability,enabling user-defined features on resolution,computation complexity,and relative *** use of SiN integration platform enables the spectrometer to exhibit excellent thermal stability of±2.0℃,effectively tackling the challenge of temperature variations at picometer-scale resolutions.

关键词： reconfigurable resolution enable

Ultralow-crosstalk,strictly non-blocking microring-based optical switch

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2019年第2期7卷 155-161页

作者： qixiang cheng LIANG YUAN DAI NATHAN C.ABRAMS YU-HAN HUNG PADRAIC E.MORRISSEY MADELEINE GLICK PETER O’BRIEN KEREN BERGMAN Department of Electrical Engineering Columbia UniversityNew York Tyndall National Institute University College Cork

We report on the first monolithically integrated microring-based optical switch in the switch-and-select architecture. The switch fabric delivers strictly non-blocking connectivity while completely canceling the first-order crosstalk. The 4 × 4 switching circuit consists of eight silicon microring-based spatial(de-)multiplexers interconnected by a Si/SiN dual-layer crossing-free central shuffle. Analysis of the on-state and off-state power transfer functions reveals the extinction ratios of individual ring resonators exceeding 25 dB, leading to switch crosstalk suppression of up to over 50 dB in the switch-and-select topology. Optical paths are assessed, showing losses as low as 0.1 dB per off-resonance ring and 0.5 dB per on-resonance ring. Photonic switching is actuated with integrated micro-heaters to give an ～24 GHz passband. The fully packaged device is flip-chip bonded onto a printed circuit board breakout board with a UV-curved fiber array.

关键词： Ultralow-crosstalk strictly non-blocking

Identifying Qingkailing(清开灵)ingredients-dependent mesenchymal-epithelial transition factor-axiation“π”structuring module with angiogenesis and neurogenesis effects

在线全文

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2024年第1期44卷 35-43页

作者： cheng Kunming YUAN Jianan LIU Jun ZHANG Shengpeng XU qixiang XIE Yong ZHAO Jingfeng ZHANG Xiaoxu TANG Xudong ZHENG Yongqiu WANG Zhong Provincial Engineering Laboratory for Screening and Re-evaluation of Active Compounds of Herbal Medicines in Southern Anhui Teaching and Research Section of Traditional Chinese MedicineSchool of PharmacyWannan Medical CollegeWuhu 241000China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of EducationDepartment of Medicinal Plant DevelopmentChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China Department of Gastroenterology Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China

OBJECTIVE:To explore the functional role of the drugdependent mesenchymal-epithelial transition(Met)-axiation"π"structural module of neurogenesis after processing by three components of Qingkailing injection in neurogenesis and angiogenesis in cerebral ***:We used a Glutathione S-transferase(GST)-pull down assay,isothermal titration calorimetry assay,and other related methods to identify the relationships among Met,inositol polyphosphate phosphatase like 1(Inppl1),and death associated protein kinase 3(Dapk3)in this allosteric *** biological effects of the modules of neurons generation composed of Met,Inppl1,and Dapk3 were measured through Western blot,apoptosis analysis,and double immunofluorescence ***:The GST-pull down assay revealed that proline-serine-threonine rich domain of Met binds to the Src homology domain of Inppl1 to form a protein-protein complex;Dapk3 with a C-terminal domain interacts weakly with the protein kinase C domain of Met in the intracellular ***,we obtained a“π”structuring module considered a neural regeneration *** biological effects of angiogenesis and neurogenesis modules composed of Met,Inppl1,and Dapk3 were also ***:The study suggested that understanding the functional modules that contribute to pharmaceutics might provide novel signatures that can be used as endpoints to define disease processes under stroke or cerebral ischemia conditions.

关键词： brain ischemia stroke neurogenesis angiogenesis modular pharmacology Met-axiation allosteric module

在线全文

学校读者我要写书评

暂无评论

玻璃纤维改性煤基固废胶结充填材料性能研究

矿业安全与环保 2024年第1期51卷 161-167,174页

作者：程强强汪浩东阴琪翔赵明翔姚越闫宝峰江苏建筑职业技术学院建筑建造学院江苏徐州221116 中国矿业大学矿业工程学院江苏徐州221116 中建八局第三建设有限公司江苏徐州210146

基于煤矸石、粉煤灰等煤基固废再生资源利用和胶结充填材料性能优化问题,研究了玻璃纤维掺量、长度和养护龄期对煤基固废胶结材料输送性能和力学性能的影响规律,探讨了玻璃纤维增强机理。实验结果表明:玻璃纤维改性煤基固废胶结材料坍... 详细信息

基于煤矸石、粉煤灰等煤基固废再生资源利用和胶结充填材料性能优化问题,研究了玻璃纤维掺量、长度和养护龄期对煤基固废胶结材料输送性能和力学性能的影响规律,探讨了玻璃纤维增强机理。实验结果表明:玻璃纤维改性煤基固废胶结材料坍落度随纤维长度和掺量的增大而减小,但均大于200 mm,满足输送性能要求;抗压强度和抗拉强度随纤维长度的增大呈先增高后降低,随纤维掺量的增加而增高的变化规律;当玻璃纤维长度为6 mm、掺量为0.3%时,质量分数为79%的煤基固废胶结材料的综合性能最佳;玻璃纤维改性煤基固废胶结材料水化反应后,生成的针状和团状产物填充了材料细小裂隙且附着于纤维表面,能够有效提高材料的力学性能。

关键词：煤基固废玻璃纤维胶结材料充填材料输送性能力学性能微观结构

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

SDD60射孔定位点火仪

石油仪器 2005年第2期19卷 48-49,52页

作者：程启祥胜利石油管理局测井公司

为了满足电缆输送射孔作业的需求和提高射孔技术与装备的技术水平,研制开发了新型SDD60射孔定位点火仪。它主要由电缆头、打捞帽、密封接头、磁定位总成、点火总成和挂接头组成,适用于60mm以上有枪身射孔器的电缆输送射孔作业。实验和... 详细信息

为了满足电缆输送射孔作业的需求和提高射孔技术与装备的技术水平,研制开发了新型SDD60射孔定位点火仪。它主要由电缆头、打捞帽、密封接头、磁定位总成、点火总成和挂接头组成,适用于60mm以上有枪身射孔器的电缆输送射孔作业。实验和现场使用表明,SDD60射孔定位点火仪结构简单、性能可靠、使用维护方便。

关键词：射孔定位点火器测井电缆测井信号高温高压

Genome-wide investigation of the bZIP transcription factor gene family in Prunus mume:Classification, evolution, expression profile and low-temperature stress responses

在线全文

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2022年第2期8卷 230-242页

作者： Ping Li Tangchun Zheng Lulu Li Jia Wang Tangren cheng qixiang Zhang Beijing Key Laboratory of Ornamental Plants Germplasm Innovation&Molecular Breeding National Engineering Research Center for FloricultureBeijing Laboratory of Urban and Rural Ecological EnvironmentEngineering Research Center of Landscape Environment of Ministry of EducationKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of EducationSchool of Landscape ArchitectureBeijing Forestry UniversityBeijing 100083China

Prunus mume is an important woody plant that has high ornamental and economic value, widely distributed and used in landscape architecture in East Asia. In plants, basic(region) leucine zipper(bZIP) transcription factors play important regulatory roles in growth, development,dormancy and abiotic stress. To date, bZIP transcription factors have not been systematically studied in P. mume. In this study, 49 bZIP genes were first identified in P. mume, and the PmbZIP family was divided into 12 groups according to the grouping principles for the Arabidopsis thaliana bZIP family. For the first time, we constructed a detailed model of the PmbZIP domains(R-x_(3)–N-(x)_7-R/K-x_(2)-K-x_(6)-L-x_(6)-L-_(6)-L). Phylogenetic and synteny analyses showed that PmbZIPs duplication events might have occurred during the large-scale genome duplication events. A relatively short time of speciation and the finding that 91.84% of the bZIP genes formed orthologous pairs between P. mume and Prunus armeniaca provided evidence of a close relationship. Gene expression patterns were analysed in different tissues and periods, indicating that PmbZIP genes with the same motifs exhibited similar expression patterns. The gene expression results showed that PmbZIP31/36/41 genes played a more prominent role in the response to freezing stress than cold stress. The expression level of almost all subset Ⅲ genes was upregulated under freezing treatment, especially after cold exposure. We analysed the gene expression patterns of PmbZIP12/31/36/41/48 and their responses to low-temperature stress, which provided useful resources for future studies on the cold/freezing-tolerant molecular breeding of P. mume.

关键词： bZIP transcription factor Gene expression Low-temperature stress