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Integrated spatial photonic XY Ising sampler based on a high-uniformity 1×8 multi-mode interferometer 被引量:1
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作者 XIN YE WENJIA ZHANG ZUYUAN HE 《Photonics Research》 2025年第5期1419-1427,共9页
Spatial photonic Ising machines,as emerging artificial intelligence hardware solutions by leveraging unique physical phenomena,have shown promising results in solving large-scale combinatorial problems.However,spatial... Spatial photonic Ising machines,as emerging artificial intelligence hardware solutions by leveraging unique physical phenomena,have shown promising results in solving large-scale combinatorial problems.However,spatial light modulator enabled Ising machines still remain bulky,are very power demanding,and have poor stability.In this study,we propose an integrated XY Ising sampler based on a highly uniform multimode interferometer and a phase shifter array,enabling the minimization of both discrete and continuous spin Hamiltonians.We elucidate the performance of this computing platform in achieving fully programmable spin couplings and external magnetic fields.Additionally,we successfully demonstrate the weighted full-rank Ising model with a linear dependence of 0.82 and weighted MaxCut problem solving with the proposed sampler.Our results illustrate that the developed structure has significant potential for larger-scale,reduced power consumption and increased operational speed,positioning it as a versatile platform for commercially viable high-performance samplers of combinatorial optimization problems. 展开更多
关键词 ising machines artificial intelligence hardware solutions spatial photonic ising machinesas integrated xy ising sampler integrated spatial photonic sampler highly uniform multimode interferometer high uniformity multi mode interferometer minimization both discrete continuou
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A near-infrared all-fiber mode monitor based on the mini-two-path Mach-Zehnder interferometer
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作者 ZHU Xiao-Jun LIU Yu +5 位作者 WU Yue ZHUANG Hao-Ran SUN Dan SHI Yue-Chun CAO Juan YANG Yong-Jie 《红外与毫米波学报》 北大核心 2025年第3期352-357,共6页
A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fibe... A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fiber,SMF)together with an optical fiber fusion splicer,establishing two distinct centimeter-level optical transmission paths.Since the high-order modes in NCF transmit near-infrared light more sensitively to curvature-induced energy leakage than the fundamental mode in SMF,the near-infrared high-order mode light leaks out of NCF when the curvature changes,causing the MTP-MZI transmission spectrum to change.By ana⁃lyzing the relationship between the curvature,transmission spectrum,and spatial frequency spectrum,the modes involved in the interference can be studied,thereby revealing the mode transmission characteristics of near-infra⁃red light in optical fibers.In the verification experiments,higher-order modes were excited by inserting a novel hollow-core fiber(HCF)into the MTP-MZI.When the curvature of the MTP-MZI changes,the near-infrared light high-order mode introduced into the device leaks out,causing the transmission spectrum to return to its origi⁃nal state before bending and before the HCF was spliced.The experimental results demonstrate that the MTP-MZI mode monitor can monitor the fiber modes introduced from the external environment,providing both theoretical and experimental foundations for near-infrared all-fiber mode monitoring in optical information systems. 展开更多
关键词 near-infrared mode monitor Mach-Zehnder interferometer two-path structure all-fiber-format
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Direction finding for wideband signal and multi-target with interferometer
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作者 PENG Bo SUN Jikang LI Chao 《Journal of Systems Engineering and Electronics》 2025年第5期1132-1139,共8页
According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of dir... According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of direction finding with interferometer for wideband signals and multiple signals scene,a frequency domain phase interferometer is proposed and the concrete implementation scheme is given.The proposed method computes the phase difference in frequency domain,and finds multi-target results with judging the spectrum amplitude changing,and uses the frequency phase difference to compute the arrival angle.Theoretical analysis and simulation results show that the proposed method effectively solves the problem of the angle estimation with phase interferometer for wideband signals,and has good performance in multiple signals scene with nonoverlapping spectrum or partially overlapping.In addition,the wider the signal bandwidth,the better direction finding performance of this algorithm. 展开更多
关键词 phase interferometer wideband signal direction finding multi-signal direction finding frequency domain interferometer
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Multi-mode luminescence anti-counterfeiting and visual iron(Ⅲ)ions RTP detection constructed by assembly of CDs&Eu3+in porous RHO zeolite
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作者 Siyu Zong Xiaowei Yu +2 位作者 Yining Yang Xin Yang Jiyang Li 《Chinese Chemical Letters》 2025年第6期567-572,共6页
Carbon dots(CDs)-based composites have shown impressive performance in fields of information encryption and sensing,however,a great challenge is to simultaneously implement multi-mode luminescence and room-temperature... Carbon dots(CDs)-based composites have shown impressive performance in fields of information encryption and sensing,however,a great challenge is to simultaneously implement multi-mode luminescence and room-temperature phosphorescence(RTP)detection in single system due to the formidable synthesis.Herein,a multifunctional composite of Eu&CDs@p RHO has been designed by co-assembly strategy and prepared via a facile calcination and impregnation treatment.Eu&CDs@p RHO exhibits intense fluorescence(FL)and RTP coming from two individual luminous centers,Eu3+in the free pores and CDs in the interrupted structure of RHO zeolite.Unique four-mode color outputs including pink(Eu^(3+),ex.254 nm),light violet(CDs,ex.365 nm),blue(CDs,254 nm off),and green(CDs,365 nm off)could be realized,on the basis of it,a preliminary application of advanced information encoding has been demonstrated.Given the free pores of matrix and stable RTP in water of confined CDs,a visual RTP detection of Fe^(3+)ions is achieved with the detection limit as low as 9.8μmol/L.This work has opened up a new perspective for the strategic amalgamation of luminous vips with porous zeolite to construct the advanced functional materials. 展开更多
关键词 Carbon dots ZEOLITE Host-vip assembly multi-mode luminescence Phosphorescence detection Information encryption
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Strength through unity:Alkaline phosphatase-responsive AIEgen nanoprobe for aggregation-enhanced multi-mode imaging and photothermal therapy of metastatic prostate cancer
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作者 Ze Wang Hao Liang +7 位作者 Annan Liu Xingchen Li Lin Guan Lei Li Liang He Andrew K.Whittaker Bai Yang Quan Lin 《Chinese Chemical Letters》 2025年第2期261-268,共8页
Prostate cancer(PCa)is characterized by high incidence and propensity for easy metastasis,presenting significant challenges in clinical diagnosis and treatment.Tumor microenvironment(TME)-responsive nanomaterials prov... Prostate cancer(PCa)is characterized by high incidence and propensity for easy metastasis,presenting significant challenges in clinical diagnosis and treatment.Tumor microenvironment(TME)-responsive nanomaterials provide a promising prospect for imaging-guided precision therapy.Considering that tumor-derived alkaline phosphatase(ALP)is over-expressed in metastatic PCa,it makes a great chance to develop a theranostics system with ALP responsive in the TME.Herein,an ALP-responsive aggregationinduced emission luminogens(AIEgens)nanoprobe AMNF self-assembly was designed for enhancing the diagnosis and treatment of metastatic PCa.The nanoprobe exhibited self-aggregation in the presence of ALP resulted in aggregation-induced fluorescence,and enhanced accumulation and prolonged retention period at the tumor site.In terms of detection,the fluorescence(FL)/computed tomography(CT)/magnetic resonance(MR)multi-mode imaging effect of nanoprobe was significantly improved post-aggregation,enabling precise diagnosis through the amalgamation of multiple imaging modes.Enhanced CT/MR imaging can achieve assist preoperative tumor diagnosis,and enhanced FL imaging technology can achieve“intraoperative visual navigation”,showing its potential application value in clinical tumor detection and surgical guidance.In terms of treatment,AMNF showed strong absorption in the near infrared region after aggregation,which improved the photothermal treatment effect.Overall,our work developed an effective aggregation-enhanced theranostic strategy for ALP-related cancers. 展开更多
关键词 AIE Prostate cancer ALP responsive Enhanced multi-mode imaging Enhanced photothermal therapy
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Signal estimation bias in x-ray dark-field imaging using dual phase grating interferometer
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作者 Zhi-Li Wang Zun Zhang +1 位作者 Heng Chen Xin Ge 《Chinese Physics B》 2025年第3期550-558,共9页
In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean inten... In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean intensity,amplitude and visibility signals may be intrinsically biased.However,it is still unclear how large these biases are and how the data acquisition parameters influence the biases in the extracted signals.This work set out to address these questions.Analytical expressions of the biases of the extracted signals were theoretically derived by using a second-order Taylor series expansion.Extensive numerical simulations were performed to validate the theoretical results.It is illustrated that while the estimated mean intensity signal is always unbiased,the estimated amplitude and visibility signals are both positively biased.While the biases of the estimated amplitude signals are proportional to the inverse of the total number of phase steps,the biases of the estimated visibility signals are inversely proportional to the product of the total number of phase steps and the mean number of photons counted per phase step.Meanwhile,it is demonstrated that the dependence of the biases on the mean visibility is quite different from that of Talbot-Lau interferometer due to the difference in the intensity model.We expect that these results can be useful for data acquisition optimizations and interpretation of x-ray dark-field images. 展开更多
关键词 x-ray imaging dual phase grating interferometer dark-field imaging signal bias
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Learning-Based Delay Sensitive and Reliable Traffic Adaptation for DC-PLC and 5G Integrated Multi-Mode Heterogeneous Networks
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作者 Tian Gexing Wang Ruiqiuyu +6 位作者 Pan Chao Zhou Zhenyu Yang Junzhong Zhao Chenkai Chen Bei Yang Sen Shahid Mumtaz 《China Communications》 2025年第4期65-80,共16页
Low-carbon smart parks achieve selfbalanced carbon emission and absorption through the cooperative scheduling of direct current(DC)-based distributed photovoltaic,energy storage units,and loads.Direct current power li... Low-carbon smart parks achieve selfbalanced carbon emission and absorption through the cooperative scheduling of direct current(DC)-based distributed photovoltaic,energy storage units,and loads.Direct current power line communication(DC-PLC)enables real-time data transmission on DC power lines.With traffic adaptation,DC-PLC can be integrated with other complementary media such as 5G to reduce transmission delay and improve reliability.However,traffic adaptation for DC-PLC and 5G integration still faces the challenges such as coupling between traffic admission control and traffic partition,dimensionality curse,and the ignorance of extreme event occurrence.To address these challenges,we propose a deep reinforcement learning(DRL)-based delay sensitive and reliable traffic adaptation algorithm(DSRTA)to minimize the total queuing delay under the constraints of traffic admission control,queuing delay,and extreme events occurrence probability.DSRTA jointly optimizes traffic admission control and traffic partition,and enables learning-based intelligent traffic adaptation.The long-term constraints are incorporated into both state and bound of drift-pluspenalty to achieve delay awareness and enforce reliability guarantee.Simulation results show that DSRTA has lower queuing delay and more reliable quality of service(QoS)guarantee than other state-of-the-art algorithms. 展开更多
关键词 DC-PLC and 5G integration multi-mode heterogeneous networks traffic adaptation traffic admission control traffic partition
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Temporal SU(1,1) Interferometer Based on Four- Wave Mixing Time Lens and Its Applications in Ultrafast Time-Frequency Manipulation
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作者 Tianyu Liu Zepeng Liu 《Journal of Electronic Research and Application》 2025年第4期327-336,共10页
Temporal optics,which enables lossless manipulation of ultrafast pulses,offers a new dimension for the regulation of quantum optical fields.In this paper,we established a temporal Fourier transform(TF)system based on ... Temporal optics,which enables lossless manipulation of ultrafast pulses,offers a new dimension for the regulation of quantum optical fields.In this paper,we established a temporal Fourier transform(TF)system based on a four-wave mixing(FWM)time lens and constructed a full quantum theoretical model for the resulting temporal SU(1,1)interferometer.This interferometer has high temporal resolution,can impose interference in both time and frequency domains,and is sensitive to the phase derivative.By introducing linear time-varying phase modulation,we achieved sub-picosecond precision in temporal autocorrelation measurements and generatedan optical frequency comb with a fixed interval based on a feedback iteration mechanism.Theoretical analysis revealsthe crucial regulatory role of time-frequency coupling in quantum interference,providing novel solutions for ultrafast quantum imaging,temporal mode encoding,and the generation of optical frequency quantization. 展开更多
关键词 Temporal SU(1 1)interferometer Four-wave mixing time lens Optical frequency comb Temporal optics
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Space-Borne Interferometers to Detect Thousands of Memory Signals Emitted by Stellar-Mass Binary Black Holes
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作者 Shaoqi Hou Zhi-Chao Zhao +1 位作者 Zhoujian Cao Zong-Hong Zhu 《Chinese Physics Letters》 2025年第10期323-330,共8页
The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory si... The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory signals from stellar-mass binary black holes(BBHs),typically targeted by ground-based detectors.We use DECIGO detector as an example.Over 5 years,DECIGO is estimated to detect approximately 2,036 memory signals(SNRs>3)from stellar-mass BBHs.Simulations used frequency-domain memory waveforms for direct SNR estimation.Predictions utilized a GWTC-3 constrained BBH population model(Power law+Peak mass,DEFAULT spin,Madau-Dickinson merger rate).The analysis used conservative lower merger rate limits and considered orbital eccentricity.The high detection rate stems from strong memory signals within DECIGO’s bandwidth and the abundance of stellar-mass BBHs.This substantial and conservative detection count enables statistical use of the memory effect for fundamental physics and astrophysics.DECIGO exemplifies that space interferometers may better detect memory signals from smaller mass binaries than their typical targets.Detectors in lower frequency bands are expected to find strong memory signals from∼10^(4)M⊙binaries. 展开更多
关键词 space borne interferometer detect memory signals gravitational memory effect decigo detector binary black holes bbhs typically stellar mass binary black holes signal noise ratio
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Research on a compact and high sensitivity gas pressure sensor based on fiber Fabry-Pérot interferometer and Bragg grating
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作者 LIU Qinpeng XING Meihua +2 位作者 YANG Di LIU Bo YAN Cheng 《Optoelectronics Letters》 2025年第6期321-327,共7页
A compact and highly sensitive gas pressure and temperature sensor based on Fabry-Pérot interferometer(FPI)and fiber Bragg grating(FBG)is proposed and demonstrated experimentally in this paper.The theoretical mod... A compact and highly sensitive gas pressure and temperature sensor based on Fabry-Pérot interferometer(FPI)and fiber Bragg grating(FBG)is proposed and demonstrated experimentally in this paper.The theoretical model for pressure and temperature sensing is established.Building on this foundation,a novel micro silicon cavity sensor structure sensitive to pressure is devised downstream of an FBG.The concept of separate measurement and the mechanisms enhancing pressure sensitivity are meticulously analyzed,and the corresponding samples are fabricated.The experimental results indicate that the pressure sensitivity of the sensor is-747.849 nm/MPa in 0—100 k Pa and its linearity is 99.7%and it maintains good stability in 150 min.The sensor offers the advantages of compact size,robust construction,easy fabrication,and high sensitivity,making it potentially valuable for micro-pressure application. 展开更多
关键词 fiber bragg grating fbg gas pressure sensor temperature sensor separate measurement fiber Bragg grating fiber Fabry P rot interferometer theoretical model pressure temperature sensing micro silicon cavity sensor structure
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MATHEMATICAL MODEL OF ~4He QUANTUM INTERFEROMETER GYROSCOPE 被引量:5
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作者 郑睿 赵伟 +2 位作者 刘建业 谢征 冯铭瑜 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期360-366,共7页
The mathematical model of 4He quantum interferometer gyroscope is presented. The model includes the driven equation, the current equation and the position equation. Therefore, it can sufficiently describe the gyro- sc... The mathematical model of 4He quantum interferometer gyroscope is presented. The model includes the driven equation, the current equation and the position equation. Therefore, it can sufficiently describe the gyro- scope system. The driven equation shows the thermally driven gyroscope can work for a long time but the pres- sure driven one cannot. From the current equation, the superfluid currents passing through the weak link contain the AC currents which show the rotation flux, and other currents caused by drive. As shown in the position equa- tion, the displacement of diaphragm is the only detectable parameter in the gyroscope system. The model is tested by the simulations based on experimental parameters, and can be used to research performance of the gyroscope and analyse the gyroscope error. 展开更多
关键词 4He quantum interferometer gyroscope mathematical model pressure drive thermal drive
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Time varying congestion pricing for multi-class and multi-mode transportation system with asymmetric cost functions
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作者 钟绍鹏 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期77-82,共6页
This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combin... This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combined applications of the space-time expanded network(STEN) and the conventional network equilibrium modeling techniques,a multi-class,multi-mode and multi-criteria traffic network equilibrium model is developed.Travelers of different classes have distinctive value of times(VOTs),and travelers from the same class perceive their travel disutility or generalized costs on a route according to different weights of travel time and travel costs.Moreover,the symmetric cost function model is extended to deal with the interactions between buses and private cars.It is found that there exists a uniform(anonymous) link toll pattern which can drive a multi-class,multi-mode and multi-criteria user equilibrium flow pattern to a system optimum when the system's objective function is measured in terms of money.It is also found that the marginal cost pricing models with a symmetric travel cost function do not reflect the interactions between traffic flows of different road sections,and the obtained congestion pricing toll is smaller than the real value. 展开更多
关键词 time varying congestion pricing ASYMMETRIC MULTI-CLASS multi-mode MULTI-CRITERIA
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Fourier Spectrometer based on Wide-range and Phase-locked Michelson Interferometer with Femtosecond Laser Excitation
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作者 王自鑫 谢向生 +1 位作者 邓俊祺 周建英 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期1-4,I0001,共5页
A wide-range and phase-locked Michelson interferometer technique is described. This technique combined with femtosecond laser is used to measure the spectrum of the rare-earth ion Nd:YVO4, which presents very high si... A wide-range and phase-locked Michelson interferometer technique is described. This technique combined with femtosecond laser is used to measure the spectrum of the rare-earth ion Nd:YVO4, which presents very high signal to noise ratio of interferometric intensity output and higher spectral resolution than traditional grating spectrophotometer. 展开更多
关键词 Wide-ranged and phase-locked Michelson interferometer Fourier spectrometer Femtosecond laser High signal to noise ratio High resolution
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Electro-Optical Effect Measurement of Thin-Film Material Using PM Fiber Mach-Zehnder Interferometer 被引量:1
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作者 屠晓光 赵雷 +4 位作者 陈平 陈少武 左玉华 余金中 王启明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第7期1012-1016,共5页
A polarization-maintaining (PM) fiber Mach-Zehnder (MZ) interferometer has been established to measure the EO effect of very thin film materials with optical anisotropy. Unlike a common MZ interferometer, all the ... A polarization-maintaining (PM) fiber Mach-Zehnder (MZ) interferometer has been established to measure the EO effect of very thin film materials with optical anisotropy. Unlike a common MZ interferometer, all the components are connected via polarization-maintaining fibers. At the same time, a polarized DFB laser with a maximum power output of 10mW is adopted as the light source to induce a large extinction ratio. Here,we take it to determine the electro-optical coefficients of a very thin superlattice structure with GaAs, KTP, and GaN as comparative samples. The measured EO coefficients show good comparability with the others. 展开更多
关键词 electro-optic effect polarization-maintaining fiber Mach-Zehnder interferometer
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大学英语的Multi-Mode教学模式
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作者 郑洁雯 《中国科教创新导刊》 2007年第27期224-224,226,共2页
针对目前高职院校大学英语教学普遍存在的问题,结合全国性大学英语教学需要改革的迫切要求,笔者对所在院校研究并应用的Multi-Mode教学模式进行分析说明,其关键性在于培养学生自主学习的积极性,较好地落实教学任务,提高学生参加英语等... 针对目前高职院校大学英语教学普遍存在的问题,结合全国性大学英语教学需要改革的迫切要求,笔者对所在院校研究并应用的Multi-Mode教学模式进行分析说明,其关键性在于培养学生自主学习的积极性,较好地落实教学任务,提高学生参加英语等级考试的通过率。 展开更多
关键词 multi-mode教学模式 编串故事 多媒体教学 写作
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Elementary analysis of interferometers for wave particle duality test and the prospect of going beyond the complementarity principle 被引量:5
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作者 李志远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期202-214,共13页
A distinct method to show a quantum object behaving both as wave and as particle is proposed and described in some detail. We make a systematic analysis using the elementary methodology of quantum mechanics upon Young... A distinct method to show a quantum object behaving both as wave and as particle is proposed and described in some detail. We make a systematic analysis using the elementary methodology of quantum mechanics upon Young's two-slit interferometer and the Mach-Zehnder two-arm interferometer with the focus placed on how to measure the interference pattern (wave nature) and the which-way information (particle nature) of quantum objects. We design several schemes to simultaneously acquire the which-way information for an individual quantum object and the high-contrast interference pattern for an ensemble of these quantum objects by placing two sets of measurement instruments that are well separated in space and whose perturbation of each other is negligibly small within the interferometer at the same time. Yet, improper arrangement and cooperation of these two sets of measurement instruments in the interferometer would lead to failure of simultaneous observation of wave and particle behaviors. The internal freedoms of quantum objects could be harnessed to probe both the which-way information and the interference pattern for the center-of-mass motion. That quantum objects can behave beyond the wave-particle duality and the complementarity principle would stimulate new conceptual examination and exploration of quantum theory at a deeper level. 展开更多
关键词 wave-particle duality complementarity principle atom interferometer
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Simulation of distributed optical fiber disturbance detection system based on Sagnac/Mach-Zehnder interferometer and cross-correlation location 被引量:2
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作者 方捻 李杰 +2 位作者 王陆唐 黄肇明 杨烨 《Journal of Shanghai University(English Edition)》 CAS 2011年第2期115-118,共4页
A distributed optical fiber disturbance detection system consisted of a Sagnac interferometer and a Mach-Zehnder interferometer is demonstrated. Two interferometers outputs are connected to an electric band-pass filte... A distributed optical fiber disturbance detection system consisted of a Sagnac interferometer and a Mach-Zehnder interferometer is demonstrated. Two interferometers outputs are connected to an electric band-pass filter via a detector respectively. The central frequencies of the two filters are selected adaptively according to the disturbance frequency. The disturbance frequency is obtained by either frequency spectrum of the two interferometers outputs. An alarm is given out only when the Sagnac interferometer output is changed. A disturbance position is determined by calculating a time difference with a cross-correlation method between the filter output connected to the Sagnac interferometer and derivative of the filter output connected to the Mach-Zehnder interferometer. The frequency spectrum, derivative and cross-correlation are obtained by a signal processing system. Theory analysis and simulation results are presented. They show that the system structure and location method are effective, accurate, and immune to environmental variations. 展开更多
关键词 Sagnac interferometer Mach-Zehnder interferometer distributed optical fiber disturbance detection system cross-correlation LOCATION
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Multi-mode diagnosis of a gas turbine engine using an adaptive neuro-fuzzy system 被引量:9
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作者 Houman HANACHI Jie LIU Christopher MECHEFSKE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第1期1-9,共9页
Gas Turbine Engines (GTEs) are vastly used for generation of mechanical power in a wide range of applications from airplane propulsion systems to stationary power plants. The gaspath components of a GTE are exposed ... Gas Turbine Engines (GTEs) are vastly used for generation of mechanical power in a wide range of applications from airplane propulsion systems to stationary power plants. The gaspath components of a GTE are exposed to harsh operating and ambient conditions, leading to several degradation mechanisms. Because GTE components are mostly inaccessible for direct measure- ments and their degradation levels must be inferred from the measurements of accessible parameters, it is a challenge to acquire reliable information on the degradation conditions of the parts in different fault modes. In this work, a data-driven fault detection and degradation estima- tion scheme is developed for GTE diagnostics based on an Adaptive Neuro-Fuzzy Inference System (ANFIS). To verify the performance and accuracy of the developed diagnostic framework on GTE data, an ensemble of measurable gas path parameters has been generated by a high-fidelity GTE model under (a) diverse ambient conditions and control settings, (b) every possible combination of degradation symptoms, and (c) a broad range of signal to noise ratios. The results prove the competency of the developed framework in fault diagnostics and reveal the sensitivity of diagnostic results to measurement noise for different degradation symptoms. 展开更多
关键词 Fault detection multi-mode diagnosis Measurement noise Real-time diagnosis
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Experimental research on the feature of an x-ray Talbot–Lau interferometer versus tube accelerating voltage 被引量:3
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作者 王圣浩 Margie P.Olbinado +7 位作者 Atsushi Momose 韩华杰 胡仁芳 王志立 高昆 张凯 朱佩平 吴自玉 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期673-678,共6页
X-ray Talbot-Lau interferometer has been used most widely to perform x-ray phase-contrast imaging with a con- ventional low-brilliance x-ray source, and it yields high-sensitivity phase and dark-field images of sample... X-ray Talbot-Lau interferometer has been used most widely to perform x-ray phase-contrast imaging with a con- ventional low-brilliance x-ray source, and it yields high-sensitivity phase and dark-field images of samples producing low absorption contrast, thus beating tremendous potential for future clinical diagnosis. In this work, by changing the accel- erating voltage of the x-ray tube from 35 kV to 45 kV, x-ray phase-contrast imaging of a test sample is performed at each integer value of the accelerating voltage to investigate the characteristic of an x-ray Talbot-Lau interferometer (located in the Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Japan) versus tube voltage. Ex- perimental results and data analysis show that within a range this x-ray Talbot-Lau interferometer is not sensitive to the accelerating voltage of the tube with a constant fringe visibility of ~ 44%. This x-ray Talbot-Lau interferometer research demonstrates the feasibility of a new dual energy phase-contrast x-ray imaging strategy and the possibility to collect a refraction spectrum. 展开更多
关键词 x-ray Talbot-Lau interferometer x-ray imaging PHASE-CONTRAST tube accelerating voltage x-ray tube
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Ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer using a beam collimator and its application for ultrasonic imaging of seismic physical models 被引量:3
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作者 Zhi-Hua Shao Xue-Guang Qiao +1 位作者 Feng-Yi Chen and Qiang-Zhou Rongt 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期128-136,共9页
An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer (FPI) is proposed and employed for ultra- sonic imaging of seismic physical models (SPMs). The FPI comprises a flexible ultra-thin gold fil... An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer (FPI) is proposed and employed for ultra- sonic imaging of seismic physical models (SPMs). The FPI comprises a flexible ultra-thin gold film and the end face of a graded-index multimode fiber (MMF), both of which are enclosed in a ceramic tube. The MMF in a specified length can collimate the diverged light beam and compensate for the light loss inside the air cavity, leading to an increased spectral fringe visibility and thus a steeper spectral slope. By using the spectral sideband filtering technique, the collimated FP1 shows an improved ultrasonic response. Moreover, two-dimensional images of two SPMs are achieved in air by recon- structing the pulse-echo signals through using the time-of-flight approach. The proposed sensor with easy fabrication and compact size can be a good candidate for high-sensitivity and high-precision nondestructive testing of SPMs. 展开更多
关键词 fiber-optic sensor Fabry-Perot interferometer seismic physical model
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