光学与光子学期刊(英文)最新文献

筛选
英文 中文
Past, Current and Future Technologies for Optical Submarine Cables 海底光缆的过去、现在和未来技术
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.1109/PHOTONICS49561.2019.00011
H. Takeshita, Masaki Sato, Y. Inada, E. L. T. D. Gabory, Yuichi Nakamura
{"title":"Past, Current and Future Technologies for Optical Submarine Cables","authors":"H. Takeshita, Masaki Sato, Y. Inada, E. L. T. D. Gabory, Yuichi Nakamura","doi":"10.1109/PHOTONICS49561.2019.00011","DOIUrl":"https://doi.org/10.1109/PHOTONICS49561.2019.00011","url":null,"abstract":"Optical submarine cables are a crucial infrastructure as they convey 99% of internet traffic between countries and continents. Although, their history is rooted in the middle in the 19th Century with the first transatlantic telegraph cable, the uninterrupted strong growth of current internet traffic has been a prime motivation for the introduction of several disruptive technologies. In this paper, we review technologies used in past and current optical submarine cables, as well as future technological trends to increase their capacity.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"1 1","pages":"36-42"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81443845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
An Optical Neural Network Architecture based on Highly Parallelized WDM-Multiplier-Accumulator 一种基于高度并行wdm -乘加器的光神经网络结构
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.1109/PHOTONICS49561.2019.00008
T. Ishihara, Jun Shiomi, Naoki Hattori, Yutaka Masuda, A. Shinya, M. Notomi
{"title":"An Optical Neural Network Architecture based on Highly Parallelized WDM-Multiplier-Accumulator","authors":"T. Ishihara, Jun Shiomi, Naoki Hattori, Yutaka Masuda, A. Shinya, M. Notomi","doi":"10.1109/PHOTONICS49561.2019.00008","DOIUrl":"https://doi.org/10.1109/PHOTONICS49561.2019.00008","url":null,"abstract":"Future applications such as anomaly detection in a network and autonomous driving require extremely low, submicrosecond latency processing in pattern classification. Towards the realization of such an ultra-fast inference processing, this paper proposes an optical neural network architecture which can classify anomaly patterns at sub-nanosecond latency. The architecture fully exploits optical parallelism of lights using wavelength division multiplexing (WDM) in vector-matrix multiplication. It also exploits a linear optics with passive nanophotonic devices such as microring resonators, optical combiners, and passive couplers, which make it possible to construct low power and ultra-low latency optical neural networks. Optoelectronic circuit simulation using optical circuit implementation of multi-layer perceptron (MLP) demonstrates sub-nanosecond processing of optical neural network.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"73 1","pages":"15-21"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83961942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
On the Feasibility of Hybrid Electrical/Optical Switch Architecture for Large-Scale Training of Distributed Deep Learning 分布式深度学习大规模训练中混合电/光开关架构的可行性研究
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.1109/PHOTONICS49561.2019.00007
Truong Thao Nguyen, Ryousei Takano
{"title":"On the Feasibility of Hybrid Electrical/Optical Switch Architecture for Large-Scale Training of Distributed Deep Learning","authors":"Truong Thao Nguyen, Ryousei Takano","doi":"10.1109/PHOTONICS49561.2019.00007","DOIUrl":"https://doi.org/10.1109/PHOTONICS49561.2019.00007","url":null,"abstract":"Data parallelism is the dominant method used to train deep learning (DL) model on High-Performance Computing systems such as large-scale GPU clusters. When training a DL model on a large number of nodes, inter-node communication becomes bottle-neck due to its relatively higher latency and lower link bandwidth (than intra-node communication). To cope with this problem, some techniques have been proposed to (a) optimize the collective communication algorithms that take into account the network topology, (b) reduce the message size, and (c) overlap the communication and computation. All of these approaches target to deal with the large message size issue while diminishing the effect of the limitation of the inter-node network. In this study, we investigate the benefit of increasing inter-node link bandwidth by using the hybrid switching systems, i.e., Electrical Packet Switching and Optical Circuit Switching. We found that the typical data-transfer of synchronous data-parallelism training are long-live and rarely changed that can be speed-up with optical switching. Simulation results on Simgrid simulator show that our approach speed-up the training time of deep learning application around 10%.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"26 1","pages":"7-14"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74514000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Calculation of the Nonlinear Susceptibility in van der Waals Crystals 范德华晶体非线性磁化率的计算
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.4236/opj.2019.911016
Mingxi Chen, Chao Tang, T. Tanabe, Y. Oyama
{"title":"Calculation of the Nonlinear Susceptibility in van der Waals Crystals","authors":"Mingxi Chen, Chao Tang, T. Tanabe, Y. Oyama","doi":"10.4236/opj.2019.911016","DOIUrl":"https://doi.org/10.4236/opj.2019.911016","url":null,"abstract":"The development of theoretical models for crystals has led to the evolution of computational methods with which much more thorough investigations than previously possible can be done, including studies of the nonlinear optical properties. There has recently been a rise in interest in 2-dimensional materials; unfortunately, measurements of the nonlinear susceptibility of these materials in the wavelength range of the order of hundreds of nanometers by traditional methods are difficult. Studies of second-harmonic generation (SHG) from the transition-metal dichalcogenides (TMDCs), MoS2 and MoSe2, have been reported; however, SHG from other typical van der Waals crystals such as GaSe and other transition metal monochalcogenides (TMMCs) has rarely been studied under the same conditions. In this study, the 211 (i = 2, j = 1, k = 1) elements in the susceptibility matrices of GaSe, InSe, MoS2 and WS2 were calculated and compared. A tendency for the SHG intensity to weaken as the wavelength increases from 500 nm to 1000 nm was observed for GaSe and InSe, and, apart from some periodic fluctuations, no clear increase could be seen for these two materials in the SHG response curve in the near infrared. By comparison, MoS2 and WS2 have obvious peaks in both the visible and infrared bands. Calculations of the SHG response show peaks at around 500 nm (for GaSe), 570 (for InSe), 660 nm, 980 nm (for MoS2) and 580 nm, 920 nm (for WS2). Moreover, similarities between the SHG curves for GaSe and InSe and for MoS2 and WS2 were revealed, which may be due to the similarities found for these two groups of crystals.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45509392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Simulations of Photonic Quantum Networks for Performance Analysis and Experiment Design 用于性能分析和实验设计的光子量子网络模拟
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.1109/PHOTONICS49561.2019.00010
Xiaoliang Wu, Joaquín Chung, Alexander Kolar, E. Wang, Tian Zhong, R. Kettimuthu, Martin Suchara
{"title":"Simulations of Photonic Quantum Networks for Performance Analysis and Experiment Design","authors":"Xiaoliang Wu, Joaquín Chung, Alexander Kolar, E. Wang, Tian Zhong, R. Kettimuthu, Martin Suchara","doi":"10.1109/PHOTONICS49561.2019.00010","DOIUrl":"https://doi.org/10.1109/PHOTONICS49561.2019.00010","url":null,"abstract":"This work models metropolitan-scale photonic quantum networks that use time bin encoding for quantum key distribution and quantum state teleportation. We develop and validate theoretical models by comparing them with prior experimental results. We use our newly developed simulator of quantum network communication, called SeQUeNCe, to perform simulations at the individual photon level with picosecond resolution. The simulator integrates accurate models of optical components including light sources, interferometers, detectors, beam splitters, and telecommunication fiber, allowing studies of their complex interactions. Optical quantum networks have been generating significant interest because of their ability to provide secure communication, enable new functionality such as clock synchronization with unprecedented accuracy, and reduce the communication complexity of certain distributed computing problems. In the past few years experimental demonstrations moved from table-top experiments to metropolitan-scale deployments and long-distance repeater network prototypes. As the number of optical components in these experiments increases, simulation tools such as SeQUeNCe will simplify experiment planning and accelerate designs of new network protocols. The modular design of our tool will also allow modeling future technologies such as network nodes with quantum memories and quantum transducers as they become available.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"150 1","pages":"28-35"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77404518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Scalable Low-Power High-Performance Rack-Scale Optical Network 可扩展的低功耗高性能机架级光网络
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.1109/PHOTONICS49561.2019.00006
Jun Feng, Zhehui Wang, Zhifei Wang, Xuanqi Chen, Shixi Chen, Jiaxu Zhang, Jiang Xu
{"title":"Scalable Low-Power High-Performance Rack-Scale Optical Network","authors":"Jun Feng, Zhehui Wang, Zhifei Wang, Xuanqi Chen, Shixi Chen, Jiaxu Zhang, Jiang Xu","doi":"10.1109/PHOTONICS49561.2019.00006","DOIUrl":"https://doi.org/10.1109/PHOTONICS49561.2019.00006","url":null,"abstract":"As large-scale applications are demanding more computation power while Moore’s Law is slowing down, rackscale computing systems are being developed to meet the increasing computation and energy requirements. Optical interconnects have become an alternative to address the performance and energy efficiency issues of rack-scale systems because of their superiority in bandwidth, latency, and power. In this paper, we systematically analyze the rack-scale optical network (RSON) architecture with different path reservation schemes and optical inter-chip networks and the most commonly used architecture for high-performance computing systems. We explore the RSON architecture, floorplan optimized delta optical network (FODON) switch architecture and the preemptive chain feedback (PCF) scheme to optimize multi-domain path reservation. Experimental results show that the RSON with FODON switch and PCF scheme can improve system performance per energy consumption by up to 5x, and around 4x on average, while still maintaining better scalability than state-of-the-art systems.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"24 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81905535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Bubble Glow at Hydrothermal Vents as the PeTa Radiation 作为PeTa辐射的热液喷口气泡辉光
光学与光子学期刊(英文) Pub Date : 2019-11-01 DOI: 10.4236/opj.2019.911017
V. Tatartchenko
{"title":"Bubble Glow at Hydrothermal Vents as the PeTa Radiation","authors":"V. Tatartchenko","doi":"10.4236/opj.2019.911017","DOIUrl":"https://doi.org/10.4236/opj.2019.911017","url":null,"abstract":"The paper presents a physical model of a natural phenomenon, the glow of bubbles at hydrothermal vents formed during underwater volcanic activity. The basis of the model is characteristic non-equilibrium radiation under first order phase transitions that since 2010 has been referred to as the PeTa (Perelman-Tatartchenko) effect. This is the fourth paper in a series developing the model for similar physical phenomena: cavitational luminescence (CL), multi-bubble sonoluminescence (MBSL), single-bubble sonoluminescence (SBSL) and laser-induced bubble luminescence (LIBL). The previous three papers were published during 2017-2018 in this Journal. In the third one we have shown that above mentioned physical effects can be generalized as a phenomenon that we have titled “Vapour bubble luminescence” (VBL). VBL is very clearly represented in a non-equilibrium phase diagram. The essence of VBL is as follows: when there is a local decrease in pressure and/or an increase of temperature in a tiny volume of a liquid occurs, one or several bubbles filled with vapour will appear. Subsequently a very rapid pressure increase and/or temperature decrease in the same volume of liquid leads to supersaturation of the vapour inside the bubble. Upon reaching critical vapor density, instantaneous vapour condensation and emission of the phase transition energy that is accompanied by a flash (this is the PeTa effect) results in a sharp pressure decrease and the bubble collapses due to the pressure drop. This process is accompanied by a shock wave in the liquid. A similar effect occurs if bubbles filled with hot steam, for example from a cappuccino machine, are injected into a relatively large volume of cold water. The VBL model explains all experimental data concerning CL/MBSL/SBSL/LIBL and the relatively new natural phenomenon, the glow of bubbles at hydrothermal vents. Several model experiments demonstrate the PeTa effect under similar conditions. Additionally, we define the PeTa effect in all its manifestations on a non-equilibrium phase diagram. This clarifies which niches can contain VBL processes. We also demonstrate the window of transparency (WT) for the PeTa radiation during crystallization of a supercooled tellurium melt and propose the design of a cavity-free pulsed laser on the basis of similar crystallization processes.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42419731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Accuracy Improvement of Blood Glucose Measurement System Using Quantum Cascade Lasers 利用量子级联激光提高血糖测量系统的精度
光学与光子学期刊(英文) Pub Date : 2019-09-24 DOI: 10.4236/opj.2019.910014
T. Koyama, S. Kino, Y. Matsuura
{"title":"Accuracy Improvement of Blood Glucose Measurement System Using Quantum Cascade Lasers","authors":"T. Koyama, S. Kino, Y. Matsuura","doi":"10.4236/opj.2019.910014","DOIUrl":"https://doi.org/10.4236/opj.2019.910014","url":null,"abstract":"For non-invasive measurement of blood glucose levels, a measurement system based on mid-infrared, attenuated-total-reflection spectroscopy equipped with hollow optical fibers, a trapezoidal multi-reflection prism, and two fixed-wavelength quantum cascade lasers emitting different wavelengths is proposed. From the absorption spectra of lip mucosa measured by Fourier-transform infrared spectrometry, two wavelengths, 1152 cm-1 for absorption by glucose and 1186 cm-1 for the background, were chosen. To reduce measurement errors, the power distribution on the prism surface was investigated, and it was found that some high-intensity spots appear on the prism surface due to the coherency of the laser beam. This inhomogeneous power distribution causes measurement errors for slight movements of the lip mucosa. To homogenize the intensity distribution on the prism, a lens to excite higher modes in the fiber was introduced, and the incident angle was changed to suppress interference due to back-reflected light. These improvements increased the measurement stability, and in-vivo experiments demonstrated that the measured optical absorption correlates well with blood glucose levels.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44686229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Detection of Casimir Radiation from Our Sun 探测来自太阳的卡西米尔辐射
光学与光子学期刊(英文) Pub Date : 2019-09-11 DOI: 10.4236/opj.2019.99013
Richard A. Hutchin
{"title":"Detection of Casimir Radiation from Our Sun","authors":"Richard A. Hutchin","doi":"10.4236/opj.2019.99013","DOIUrl":"https://doi.org/10.4236/opj.2019.99013","url":null,"abstract":"This paper extends the previous experimental work on Planck’s constant h and the vacuum field, whose spectrum is determined by h. In particular it adds additional experimental evidence supporting temporal and spatial variations in the vacuum field, including the Sun as a source at 13 sigmas of certainty. The vacuum field has long been a mystery of physics, having enormous theoretical intensity set by Planck’s constant h and yet no obvious physical effect. Hendrick Casimir first proposed that this form of E & M radiation was real in 1948 and suggested an experiment to verify its existence. Over 50 experiments since then have confirmed that this vacuum radiation is real, is a form of electro-magnetic radiation, and varies in time and space over 10:1 in our laboratory compared to its standard QM spectrum. Two other authors have found the fine structure constant α (proportional to 1/h) is varying across the cosmos at up to 4.2 sigma certainty. All these results suggest that the vacuum field (and thus h) varies in time and space. In a previous paper we reported our tunnel diode experimental results as well as the results of six other organizations (including German, Russian and US national labs).The six organizations reported sinusoidal annual variations of 1000 - 3000 ppm (peak-to-valley) in the decay rates of 8 radionuclides over a 20-year span, including beta decay (weak interaction) and alpha decay (strong interaction). All decay rates peaked in January-February and minimized in July-August without any candidate cause suggested. We confirmed that Planck’s constant was the cause by verifying similar variations in Esaki tunnel diode current, which is purely electromagnetic. The combined data from previous strong and weak decays plus our own E & M tunnel data showed similar magnitude and time phasing for strong, weak and E & M interactions, except that the tunnel diode temporal variations were 180 deg out of phase—as we predicted. The logic for this 180 deg phase shift was straight forward. Radioactive decay and electron tunneling both have h in the denominator of the tunneling exponent, but tunnel diodes also have h2 in the numerator of the exponent due to the size of atoms being proportional to h2. This extra h2 makes the exponent proportional to h for electron tunneling instead of proportional to 1/h for strong and weak decay—shifting the annual oscillation for E & M tunnel current by 180 deg. Radioactive decay had a maximum around January-February of each year and a minimum around July-August of each year. Tunnel current (the equivalent to radioactive decay rate) had the opposite—a minimum around January of each year and a maximum around July of each year. This predicted and observed sign flip in the temporal variations between radioactive decay and electron tunneling provides strong evidence that h variations across the Earth’s orbit are the cause of these annual cycles. In this paper we take the next step by verifying whether the Sun and a pote","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41318135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Laser, Universe and Arrow of Time 激光、宇宙与时间之箭
光学与光子学期刊(英文) Pub Date : 2019-08-22 DOI: 10.4236/OPJ.2019.98012
M. Konwar, G. Baruah
{"title":"Laser, Universe and Arrow of Time","authors":"M. Konwar, G. Baruah","doi":"10.4236/OPJ.2019.98012","DOIUrl":"https://doi.org/10.4236/OPJ.2019.98012","url":null,"abstract":"We have presented a comparison between the universe and the Laser. In many ways, the physics of laser and the universe are analogous. The root of the analogy is the fact that both laser and early universe depend completely on the quantum nature. We have also presented a simple analogous example of the growth of a flower at successive stages of development and shown how the arrow of time may be represented in these cases.","PeriodicalId":64491,"journal":{"name":"光学与光子学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45195343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信