A two-dimensional （2D） optimized nanotaper mode converter is presented and analyzed using the finite- difference time-domain （FDTD） method. It can convert the mode size in a silicon pillar waveguide （PWG） from 4...
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A two-dimensional （2D） optimized nanotaper mode converter is presented and analyzed using the finite- difference time-domain （FDTD） method. It can convert the mode size in a silicon pillar waveguide （PWG） from 4 μm to 1 μm over a length of 7 μm and achieve a transmission efficiency of 83.6% at a wavelength of 1.55 μm. The dual directional mode conversion of the nanotaper and its ability to perform mode compression and expansion are also demonstrated. The broadband with high transmittance is satisfied in this structure. Using this silicon-based nanotaper, mode conversion between integrated photonic devices can be more compact and efficient.
A high-permittivity （high-k） material is applied as the gate dielectric layer in a silicon metal-oxide- semiconductor （MOS） capacitor to form a special electro-optic （EO） modulator. Both induced charge density a...
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A high-permittivity （high-k） material is applied as the gate dielectric layer in a silicon metal-oxide- semiconductor （MOS） capacitor to form a special electro-optic （EO） modulator. Both induced charge density and modulation efficiency in the proposed modulator are improved due to the special structure design and the application of the high-k material. The device has an ultra-compact dimension of 691 μm in length.
A novel method based on the use of dispersive fibers is proposed and experimentally demonstrated for measuring the high-frequency modulation index,as well as the half-wave voltage,of electro-optic phase *** dispersion...
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A novel method based on the use of dispersive fibers is proposed and experimentally demonstrated for measuring the high-frequency modulation index,as well as the half-wave voltage,of electro-optic phase *** dispersion causes the phase modulated signal to become intensity modulated,which allows for the high resolution swept frequency measurement of phase modulators,using a vector network *** proposed method holds without the restriction of small-signal approximation,which is applicable for the measurement at different driving levels and operating wavelengths.
The conservative Additive Increase Multiplicative Decrease mechanism of traditional TCP causes the link under-utilization in the Wide Area networks(WANs) due to the WANs' intrinsic nature of high latency and high ...
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The conservative Additive Increase Multiplicative Decrease mechanism of traditional TCP causes the link under-utilization in the Wide Area networks(WANs) due to the WANs' intrinsic nature of high latency and high packet *** alleviate the problem,we present the design and implantation of STAG,an Acceleration Gateway with Split-TCP in the *** is built on embedded network equipment and acts as a transparent *** STAG,a new improved congestion control method named Rapid TCP is adopted,which determines whether or not to decrease the congestion window based on the packet loss *** particular,in the fast recovery phase,it chooses different window adjustment strategies based on the current size of congestion window to achieve higher *** performance validation of STAG is done on both our emulation testbed and the real wide area *** results show that STAG with Rapid TCP effectively adapts to the high loss network environment and significantly speeds up the applications without loss of fairness.
With respect to security, the use of various terminals in the mobile Internet environment is *** terminal testing methods cannot simulate actual testing environments; thus, the test results do not accurately reflect t...
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With respect to security, the use of various terminals in the mobile Internet environment is *** terminal testing methods cannot simulate actual testing environments; thus, the test results do not accurately reflect the security of terminals. To address this problem, we designed and developed a cloud platform based automated testing system for the mobile Internet. In this system, virtualization and automation technology are utilized to integrate mobile terminals into the cloud platform as a resource, to achieve a novel cloud service called Testing as a Service(Taa S). The system consists of three functional modules: web front-end module, testing environment module, and automated testing module. We adopted the permeable automated testing tool Metasploit to perform security testing. In our test experiments, we selected 100 apps with diverse vulnerability levels, ranging from secure to vulnerable, to perform a series of functional tests. The experimental results show that this system can correctly test both the number of vulnerable apps and their corresponding vulnerability levels. As such, the designed system can flexibly configure various testing environments for different testing cases or projects, and thereby perform security testing automatically.
This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each use...
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This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each user equipment(UE) has individual communication demand. In order to maximize the communication probability of the whole system, a matching-potential game framework is designed. In detail, the channel diversity problem is decomposed into two sub-problems. One is channel-transmitter matching problem, which can be formulated as a many-to-one matching game. The other is the transmitter allocation problem which decides the transmission object that each transmitter communicates with under channel-transmitter matching result, and this sub-problem can be modeled as a potential game. A multiple round stable matching algorithm(MRSMA) is proposed, which obtains a stable matching result for the first sub-problem, and a distributed BR-based transmitter allocation algorithm(DBRTAA) is designed to reach Nash Equilibrium(NE) of the second sub-problem. Simulation results verify the effectiveness and superiority of the proposed method.
Dear editor,Boolean bent functions were introduced by Rothaus in 1976 as an interesting combinatorial object with the important property of having optimal nonlinearity[1].Since bent functions have many applications in...
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Dear editor,Boolean bent functions were introduced by Rothaus in 1976 as an interesting combinatorial object with the important property of having optimal nonlinearity[1].Since bent functions have many applications in sequence design,cryptography and algebraic coding,they have been extensively studied during the last thirty years[2,3].Over the past decades,based on bent functions,several constructions of highly nonlinear balanced functions were presented[4,5].
Since the joint probabilistic data association(JPDA)algorithm results in calculation explosion with the increasing number of targets,a multi-target tracking algorithm based on Gaussian mixture model(GMM)clustering is ...
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Since the joint probabilistic data association(JPDA)algorithm results in calculation explosion with the increasing number of targets,a multi-target tracking algorithm based on Gaussian mixture model(GMM)clustering is *** algorithm is used to cluster the measurements,and the association matrix between measurements and tracks is constructed by the posterior *** with the traditional data association algorithm,this algorithm has better tracking performance and less computational *** results demonstrate the effectiveness of the proposed algorithm.
We show that a linear relation exists between the device sensitivity and the quality （Q） factor of a dual- waveguide coupled microring resonator optical biosensor when the optimal conditions are satisfied. We also s...
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We show that a linear relation exists between the device sensitivity and the quality （Q） factor of a dual- waveguide coupled microring resonator optical biosensor when the optimal conditions are satisfied. We also show that the detection limit depends on the loss coefficient and signal-to-nosie ratio （SNR） of the overall system, rather than the circumference of the ring. For a microring resonator sensor whose Q factor is 20000, the detection limit is found to be about 10-7 with 30-dB SNR, which is in good agreement with reported experimental data. These results indicate that loss reduction is the top priority in the design and fabrication of highly sensitive microring resonator optical biosensors.
In this paper, the issue of designing transmission schedule for remote state estimation system for multiple dynamical processes is investigated. As the limited capacity of wireless channel, it is no possible that all ...
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