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Refractive Index Sensor Based on Twisted Tapered Plastic Optical Fibers

Teng, Deng, Liu, Yang, Yuan, Zheng, Deng
2019 Photonics  
We proposed a refractive index (RI) sensor employing two twisted tapered plastic optical fibers (POFs). The tapered POFs were fabricated by a heating and drawing method and were twisted around each other to form a coupled structure. The sensor consisted of two input ports, a twisted region, and two output ports. The tapered POF could make the light couple from one POF to the other easily. The twisted tapered POFs could constitute a self-referencing sensor, and by monitoring the changes of the
more » ... upling ratio, the variations of the external medium RIs could be measured. The RI sensing performances for the sensors with different fiber diameters and twisted region lengths were studied. The sensitivities of 1700%/RIU and −3496%/RIU in the RI ranges of 1.37–1.41 and 1.41–1.44 were obtained, respectively. The sensor is a low-cost solution for liquid RI measurement, which has the features of simple structure and easy fabrication.
doi:10.3390/photonics6020040 fatcat:7mxcydxc2razniqex3dbez5rsy

Displacement Sensor Based on a Small U-Shaped Single-Mode Fiber

Chuanxin Teng, Fangda Yu, Shijie Deng, Houquan Liu, Libo Yuan, Jie Zheng, Hongchang Deng
2019 Sensors  
A simple structure and easily fabricated displacement sensor was proposed and demonstrated based on a bending-induced fiber interferometer. In the design, the fiber interferometer was formed only by bending the single-mode fiber into a small U-shape without splicing, tapering, or heating pre-processing, which effectively reduces the complexity of the fabrication process, greatly enhances the mechanical strength of the sensor, and lowers the cost in the displacement sensing applications. The
more » ... lacement sensing performances for the sensor with different bending radii of 3.3 mm, 4.4 mm, 5.0 mm, and 6.3 mm were investigated. Experimental results showed that the sensor had a good linear response, and for the bending radii of 3.3, 4.4, 5.0, and 6.3 mm, the proposed sensors showed high sensitivities of 134.3, 105.1, 120.9, and 144.1 pm/μm, respectively.
doi:10.3390/s19112531 fatcat:5h2brmx3xffv5ch4ckn37mm4kq

Settling the Complexity of Computing Two-Player Nash Equilibria [article]

Xi Chen, Xiaotie Deng, Shang-Hua Teng
2007 arXiv   pre-print
Recently, Chen, Teng, and Valiant [14] extended our approximation complexity result to win-lose two-player games; Huang and Teng [28] extended both the smoothed complexity and the approximation results  ...  Then, Spielman and Teng [54] proved that the smoothed complexity of the simplex algorithm is polynomial.  ... 
arXiv:0704.1678v1 fatcat:bv5kllzvurg7fjlt2gq7d6nolu

Vortex Beam Encoded All-Optical Logic Gates Based on Nano-Ring Plasmonic Antennas

Houquan Liu, Hongchang Deng, Shijie Deng, Chuanxin Teng, Ming Chen, Libo Yuan
2019 Nanomaterials  
Vortex beam encoded all-optical logic gates are suggested to be very important in future information processing. However, within current logic devices, only a few are encoded by using vortex beams and, in these devices, some space optical elements with big footprints (mirror, dove prism and pentaprism) are indispensable components, which is not conducive to device integration. In this paper, an integrated vortex beam encoded all-optical logic gate based on a nano-ring plasmonic antenna is
more » ... ed. In our scheme, by defining the two circular polarization states of the input vortex beams as the input logic states and the normalized intensity of the plasmonic field at the center of the nano-ring as the output logic states, OR and AND (NOR and NAND) logic gates are realized when two 1st (1st) order vortex beams are chosen as the two input signals; and a NOT logic gate is obtained when one 1st order vortex beam is chosen as the input signal. In addition, by defining the two linear polarization states (x and y polarization) of the input vortex beams as the two input logic states, an XNOR logic gate is realized when two 1st order vortex beams are chosen as the two input signals.
doi:10.3390/nano9121649 pmid:31757019 pmcid:PMC6955695 fatcat:xzdyvgwmzjfyxpobtdvwp2tj74

Sparse Games Are Hard [chapter]

Xi Chen, Xiaotie Deng, Shang-Hua Teng
2006 Lecture Notes in Computer Science  
Chen and Deng [6] finally settled a long-term open problem, and proved that computing a Nash equilibrium in a two-player game is PPAD-complete.  ...  Recently, Chen, Teng, and Valiant [11] extended this result and proved that win-lose twoplayer games, in which the payoff entries are either 0 or 1, are PPAD-hard to approximate in fully polynomial time  ... 
doi:10.1007/11944874_24 fatcat:gptxmnf2jbhrxjkdssao4lmzz4

Design and Implementation of a Compact Single-Photon Counting Module

Ming Chen, Chenghao Li, Alan P. Morrison, Shijie Deng, Chuanxin Teng, Houquan Liu, Hongchang Deng, Xianming Xiong, Libo Yuan
2020 Electronics  
A compact single-photon counting module that can accurately control the bias voltage and hold-off time is developed in this work. The module is a microcontroller-based system which mainly consists of a microcontroller, a programmable negative voltage generator, a silicon-based single-photon avalanche diode, and an integrated active quench and reset circuit. The module is 3.8 cm × 3.6 cm × 2 cm in size and can communicate with the end user and be powered through a USB cable (5 V). In this
more » ... the bias voltage of the single-photon avalanche diode (SPAD) is precisely controllable from −14 V ~ −38 V and the hold-off time (consequently the dead time) of the SPAD can be adjusted from a few nanoseconds to around 1.6 μs with a setting resolution of ∼6.5 ns. Experimental results show that the module achieves a minimum dead time of around 28.5 ns, giving a saturation counting rate of around 35 Mcounts/s. Results also show that at a controlled reverse bias voltage of 26.8 V, the dark count rate measured is about 300 counts/s and the timing jitter measured is about 158 ps. Photodetection probability measurements show that the module is suited for detection of visible light from 450 nm to 800 nm with a 40% peak photon detection efficiency achieved at around 600 nm.
doi:10.3390/electronics9071131 fatcat:t23mudzgvrekjaoj3vsyiawgn4

A new shock-capturing scheme for stiff detonation waves problems [article]

Xi Deng, Honghui Teng, Bin Xie, Feng Xiao
2017 arXiv   pre-print
A new approach to prevent spurious behavior caused by conventional shock-capturing schemes when solving stiff detonation waves problems is introduced in the present work. Due to smearing of discontinuous solution by the excessive numerical dissipation, conventional shock-capturing schemes have difficulties to obtain the correct location of detonation front without enough grids resolution. To overcome the excessive numerical errors around discontinuities by traditional discretized schemes used
more » ... non-reacting high speed compressible flow, we introduce a new shock-capturing scheme in which besides linear function constructed by MUSCL (Monotone Upstream-centered Schemes for Conservation Law) scheme, a step like THINC (Tangent of Hyperbola for INterface Capturing) function is also employed as another candidate in the reconstruction process. The final reconstruction function is determined by boundary variation diminishing (BVD) algorithm by which numerical dissipation around discontinuities can be reduced significantly. The new resulted shock-capturing scheme is named MUSCL-THINC-BVD. One- and two-dimensional comparative numerical tests about stiff detonation waves problems are conducted with the 5th order WENO (Weighted Essentially Non-Oscillatory) and MUSCL-THINC-BVD scheme respectively, which show MUSCL-THINC-BVD scheme can capture the correct position of detonation waves with improved resolution while WENO scheme, in spite of higher order, produces spurious waves. Compared with other existing methods which involves extra treatments by accepting the smeared out discontinuities profiles, the current method obtain the correct but also sharp detonation front by fundamentally reducing numerical dissipation errors from shock-capturing schemes. Thus the proposed approach is an effective but simple method to solve stiff detonation problems.
arXiv:1708.01000v1 fatcat:vqsrgek5rnfw7p5hy6iu5nuhce

Liquid Level Sensor Based on a V-Groove Structure Plastic Optical Fiber

Chuanxin Teng, Houquan Liu, Hongchang Deng, Shijie Deng, Hongyan Yang, Ronghui Xu, Ming Chen, Libo Yuan, Jie Zheng
2018 Sensors  
A high sensitivity and easily fabricated liquid level sensor based on the V-groove structure plastic optical fiber (POF) was described. In the design, the V-groove structure on the POF is produced by using a die-press-print method, which effectively reduces the complexity of the fabrication process and makes it easier for mass production of liquid level sensors. This greatly enhances the usefulness of the proposed sensor in cost effective liquid level sensing applications. The transmission
more » ... cteristic of the POF could be changed when the V-groove structure was immerged or emerged by the rising or falling liquid. The liquid level sensing performances for the sensor probes with different structural parameters were investigated, and the sensor performances for the liquids with different refractive indices and the sensor dynamic response were also tested. Experimental results show that the sensor's sensitivity can reach 0.0698 mm−1, with a resolution of 2.5 mm. Results also show that the sensor has a fast response time of 920 ms.
doi:10.3390/s18093111 pmid:30223540 pmcid:PMC6164981 fatcat:tvicdnksljacngrcikpojlaswy

Computing Nash Equilibria: Approximation and Smoothed Complexity [article]

Xi Chen, Xiaotie Deng, Shang-Hua Teng
2006 arXiv   pre-print
Using an improvement on the SPERNER problem, Chen and Deng improved the result to the two dimensional case [3] .  ...  In particular, we extend the construction of Chen and Deng [6] to Brouwer's fixed-point problem in high dimensions.  ... 
arXiv:cs/0602043v2 fatcat:rjauce5pwbhr7e6ceejmva334a

FaceCollage

Fuwen Tan, Chi-Wing Fu, Teng Deng, Jianfei Cai, Tat-Jen Cham
2017 Proceedings of the 2017 ACM on Multimedia Conference - MM '17  
This paper presents FaceCollage, a robust and real-time system for head reconstruction that can be used to create easy-to-deploy telepresence systems, using a pair of consumer-grade RGBD cameras that provide a wide range of views of the reconstructed user. A key feature is that the system is very simple to rapidly deploy, with autonomous calibration and requiring minimal intervention from the user, other than casually placing the cameras. This system is realized through three technical
more » ... ions: (1) a fully automatic calibration method, which analyzes and correlates the left and right RGBD faces just by the face features; (2) an implementation that exploits the parallel computation capability of GPU throughout most of the system pipeline, in order to attain real-time performance; and (3) a complete integrated system on which we conducted various experiments to demonstrate its capability, robustness, and performance, including testing the system on twelve participants with visually-pleasing results.
doi:10.1145/3123266.3123281 dblp:conf/mm/TanFDCC17 fatcat:hlsmrwb66jggviwzoagmbpfose

An Enhanced Plastic Optical Fiber-Based Surface Plasmon Resonance Sensor with a Double-Sided Polished Structure

Lian Liu, Shijie Deng, Jie Zheng, Libo Yuan, Hongchang Deng, Chuanxin Teng
2021 Sensors  
Teng et al. [31] optimized the sensing performance of the side-polished U-shape POF-based SPR sensor.  ... 
doi:10.3390/s21041516 pmid:33671630 fatcat:zr3sp4m6lnb67lrihmc6hpqrci

Mass Spectrometry Applications in Biomedical Research

Fa-Yun Che, Hai-Teng Deng, Shi-Jian Ding
2015 BioMed Research International  
Fa-Yun Che Hai-Teng Deng Shi-Jian Ding  ... 
doi:10.1155/2015/827370 pmid:26090447 pmcid:PMC4454730 fatcat:takbxj4whfaijcqp2eqhlxkpea

CornerNet-Lite: Efficient Keypoint Based Object Detection [article]

Hei Law, Yun Teng, Olga Russakovsky, Jia Deng
2020 arXiv   pre-print
Keypoint-based methods are a relatively new paradigm in object detection, eliminating the need for anchor boxes and offering a simplified detection framework. Keypoint-based CornerNet achieves state of the art accuracy among single-stage detectors. However, this accuracy comes at high processing cost. In this work, we tackle the problem of efficient keypoint-based object detection and introduce CornerNet-Lite. CornerNet-Lite is a combination of two efficient variants of CornerNet:
more » ... ade, which uses an attention mechanism to eliminate the need for exhaustively processing all pixels of the image, and CornerNet-Squeeze, which introduces a new compact backbone architecture. Together these two variants address the two critical use cases in efficient object detection: improving efficiency without sacrificing accuracy, and improving accuracy at real-time efficiency. CornerNet-Saccade is suitable for offline processing, improving the efficiency of CornerNet by 6.0x and the AP by 1.0% on COCO. CornerNet-Squeeze is suitable for real-time detection, improving both the efficiency and accuracy of the popular real-time detector YOLOv3 (34.4% AP at 30ms for CornerNet-Squeeze compared to 33.0% AP at 39ms for YOLOv3 on COCO). Together these contributions for the first time reveal the potential of keypoint-based detection to be useful for applications requiring processing efficiency.
arXiv:1904.08900v2 fatcat:6s22vx6sjbfd5mu6d3c5gqdcmq

Coherent Perfect Absorber Based On Antisymmetric Metasurface With Gain Material

Ming Chen, Chen Chen, Shijie Deng, Chongyun WANG, Houquan Liu, Chuanxin Teng, Yu Cheng, Hongyan Yang, Ronghui Xu, Hongchang Deng, Libo Yuan
2020 IEEE Photonics Journal  
In this paper, we proposed a two ports coherent perfect absorber based on antisymmetric metasurface with gain material which is able to effectively regulate the absorption of the coherent incident wave under the condition of unequal incident intensities. This design overcomes the limitation that exists in the previous coherent controller which can only be applied to coherent light of equal intensity without gain material. In the proposed absorber, the metal strips of different lengths are
more » ... ed in an antisymmetric manner on the interlayer, a gain material layer is introduced to regulate the unequal intensity coherent light and the electromagnetic response mode which can be selectively strengthened and weakened by modulating the phase difference between two incident waves, and a high coherent absorption under the condition of asymmetric incident wave can be realized. Results show that the proposed absorber achieve coherent perfect absorption at the frequency of 15.25 THz and 17.75 THz, which can change the total absorption in the range from 27.41% to 98.55%, and from 27.55% to 97.88%, respectively. This paper may serve as an important tool for all-optical information transmission and data processing.
doi:10.1109/jphot.2020.2992100 fatcat:khhz5zdocjgudiq3b7dil32uve

Engineered T lymphocytes eliminate lung metastases in models of pancreatic cancer

Qiang Sun, Shixin Zhou, Jingjing Zhao, Changwen Deng, Ruidi Teng, Yiding Zhao, Jiajia Chen, Jiebin Dong, Ming Yin, Yun Bai, Hongkui Deng, Jinhua Wen
2018 OncoTarget  
Pancreatic cancer is known as one of the most lethal cancers in the world. A majority of advanced stage pancreatic cancer patients are diagnosed with distant metastasis and given poor prognoses, calling for a better therapeutic option. Mesothelin, which is overexpressed in pancreatic cancer and other solid tumors, is a potential target for pancreatic cancer immunotherapy. Adoptive transfer of T cells engineered with chimeric antigen receptors (CART cells) was effective for treating
more » ... leukemia, but it is more difficult for CART cells to eliminate solid tumors. Because distal metastasis is an important malignant behavior of solid tumors, we investigated whether meso-CART cells exert anti-tumor effects against distant metastases. After expressing meso-CAR in human primary T lymphocytes, the resultant meso-CART cells released cytokines in response to and exhibited cytolytic effects on mesothelin-positive tumor cells in vitro. Injection of meso-CART cells into tumor-bearing mice moderately delayed subcutaneous tumor growth and eliminated lung metastases. This is the first study to show that meso-CART cells are effective against lung metastases induced by intravenous injection of pancreatic tumor cells. Our results suggest that meso-CART cells may be an effective clinical treatment for mesothelin-positive primary and metastatic tumors in pancreatic cancer patients.
doi:10.18632/oncotarget.24122 pmid:29568387 pmcid:PMC5862608 fatcat:sdssoetbsfhk5mdtb44dccffxe
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