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A lowcost Fiber Bragg Grating (FBG) Sensing System based on code division multiplexing access (CDMA) technology is proposed. The system using semiconductor optical amplifier and a broadband source is experimented. Without a tunabl...
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A lowcost Fiber Bragg Grating (FBG) Sensing System based on code division multiplexing access (CDMA) technology is proposed. The system using semiconductor optical amplifier and a broadband source is experimented. Without a tunable laser source or electro-optic switch driven, the price of system is very low. CDMA is used to separate each reflected sensor. The experimental results show that theory is correct.
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This paper presents the quasi-static and cyclic fracture behavior of three rapidly solidification processed magnesium alloys. Specimens of the magnesium alloy were deformed to failure in simple uniaxial tension, total strain ampli...
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This paper presents the quasi-static and cyclic fracture behavior of three rapidly solidification processed magnesium alloys. Specimens of the magnesium alloy were deformed to failure in simple uniaxial tension, total strain amplitude-control andunder stress-amplitude control. The cyclic strain resistance, low-cycle fatigue and high-cycle fatigue characteristics of the alloys are discussed in light of alloy composition. All three alloys follow the Basquin and Coffin-Manson relationships andexhibit a single slope for the variation of cyclic elastic and plastic strain amplitudes with reversals-to-fatigue failure. The cyclic fatigue response, and quasi-static and cyclic fracture characteristics of the alloys are discussed in light of competing and synergistic influences of nature of loading, intrinsic microstructural effects and matrix deformation characteristics.
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With the continuous development and progress of science and technology, the field of mixed reality applications has involved scientific research, medicine, entertainment, education, information dissemination, and people's daily li...
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With the continuous development and progress of science and technology, the field of mixed reality applications has involved scientific research, medicine, entertainment, education, information dissemination, and people's daily lives; This paper will focus on the application of mixed reality in the field of education and teaching, relying on the characteristics of mixed reality technology. This article will use the combination of mixed reality and smart glasses to fully consider the characteristics of photography darkroom teaching, design and produce a mixed reality photography darkroom teaching software, and explore the feasibility of the application of mixed reality in teaching. This paper will use literature research methods, practical research methods, and survey methods as the main methods of research topics to determine the importance, feasibility, and necessity of the relevant theories studied in this paper. The application of mixed reality technology in photography darkroom teaching can not only solve many problems in the existing darkroom teaching methods, but also develop and expand students' Independent learning ability. It is concluded from this that mixed reality teaching software has the feasibility of sustainable development, which brings particular application value to the development and research of other education and art discipline software.
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A method is presented for generating multiple-channel color-entangled photon pairs simultaneously based on type Ⅰ quasi-phase-matched spontaneous parametric downconversion pumped in a single periodically poled lithium niobate (PP...
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A method is presented for generating multiple-channel color-entangled photon pairs simultaneously based on type Ⅰ quasi-phase-matched spontaneous parametric downconversion pumped in a single periodically poled lithium niobate (PPLN) crystal. It is predicted that one-, and two-channel color-entangled photon pairs can be simultaneously generated just by suitably choosing the PPLN grating period and the pump frequency. We point out that the full width at half maximum (FWHM) of idler and signal light are broadened dramatically due to spontaneous parametric downconversion in case of a pulsed pump. Then this method is applied for generating multiple-channel polarization-entangled photon pairs simultaneously based on type Ⅱ quasi-phase-matched spontaneous parametric downconversion.
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摘要 :
A method is presented for generating multiple-channel color-entangled photon pairs simultaneously based on type Ⅰ quasi-phase-matched spontaneous parametric downconversion pumped in a single periodically poled lithium niobate (PP...
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A method is presented for generating multiple-channel color-entangled photon pairs simultaneously based on type Ⅰ quasi-phase-matched spontaneous parametric downconversion pumped in a single periodically poled lithium niobate (PPLN) crystal. It is predicted that one-, and two-channel color-entangled photon pairs can be simultaneously generated just by suitably choosing the PPLN grating period and the pump frequency. We point out that the full width at half maximum (FWHM) of idler and signal light are broadened dramatically due to spontaneous parametric downconversion in case of a pulsed pump. Then this method is applied for generating multiple-channel polarization-entangled photon pairs simultaneously based on type Ⅱ quasi-phase-matched spontaneous parametric downconversion.
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Wildfire disasters can cause transmission line failures characterized by low re-closing rate and high breaker rejecting rate, which dramatically increase the risk of cascading failures in power grids. Firstly, the characteristics ...
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Wildfire disasters can cause transmission line failures characterized by low re-closing rate and high breaker rejecting rate, which dramatically increase the risk of cascading failures in power grids. Firstly, the characteristics of power grid cascading failures under multiple wildfire disasters are analyzed from the perspectives of multi fire high impedance faults, evolution pathways of power grid cascading reactions, and emergency disposal requirements for power grid cascading failures under multi-fire disasters. Secondly, establish quantitative decision-making indicators for emergency disposal on cascading failures risk, such as, the probability of transmission line cascading failures, the risk of power grid cascading failures, and the weight of transmission line cascading failures risk. Thirdly, an optimal decision-making method for emergency disposal of cascading failures risk was proposed, which considered the deployment of fire extinguishing equipment and the adjustment of power grid operation mode. Finally, the effectiveness of the proposed method is verified by a practical case of power grid.
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Fuel cells have attracted much attention due to their high power generation efficiency, low environmental pollution, and high reliability. However, the output voltage of the fuel cells varies greatly, which cannot meet the fast re...
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Fuel cells have attracted much attention due to their high power generation efficiency, low environmental pollution, and high reliability. However, the output voltage of the fuel cells varies greatly, which cannot meet the fast response requirements of load transients, therefore, a DC/DC converter is required to maintain the stability of the output voltage. This paper proposes a wide-voltage range multi-phase interleaved DC/DC converter topology suitable for fuel cells. The converter can be adjusted into the Buck mode, Boost mode and Extended-Duty-Ratio (EDR) mode. And this topology has the characteristics of wide range input, high gain and low ripple. In addition, by adopting the current control method, current sharing and fast dynamic response are well realized. The operating principle and the control algorithm of the topology are discussed in this paper, and the validity of the analysis is verified by simulation.
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Based on the background of the post international financial crisis, related study whether the impacts of different type capital account liberalization on the financial instability is significant and how to choose the optimal insta...
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Based on the background of the post international financial crisis, related study whether the impacts of different type capital account liberalization on the financial instability is significant and how to choose the optimal instants of the openness implementation is much more valuable. In this paper, we will analyze the influence of the outbound portfolio investment and loan flowing liberalization on the financial instability. Subsequently, we introduce the switch system optimal control model to simulate the optimal instants of the related liberalization in China. The results show that the outbound portfolio investment liberalization will directly lead to reduce the financial instability in low degree openness economies and will increase the risks in high degree openness economies. The loan flowing liberalization will lead to increase the financial instability and the worsening impact on the low degree liberalization economies is much higher. Ensuring the premise of domestic financial stability, the optimal instant of China outbound portfolio investment liberalization should be located from January to the end of February 2016, while the optimal instant of the loan flowing liberalization will be promoted from July to September 2011.
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摘要 :
Based on the background of the post international financial crisis, related study whether the impacts of different type capital account liberalization on the financial instability is significant and how to choose the optimal i...
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Based on the background of the post international financial crisis, related study whether the impacts of different type capital account liberalization on the financial instability is significant and how to choose the optimal instants of the openness implementation is much more valuable. In this paper, we will analyze the influence of the outbound portfolio investment and loan flowing liberalization on the financial instability. Subsequently, we introduce the switch system optimal control model to simulate the optimal instants of the related liberalization in China. The results show that the outbound portfolio investment liberalization will directly lead to reduce the financial instability in low degree openness economies and will increase the risks in high degree openness economies. The loan flowing liberalization will lead to increase the financial instability and the worsening impact on the low degree liberalization economies is much higher. Ensuring the premise of domestic financial stability, the optimal instant of China outbound portfolio investment liberalization should be located from January to the end of February 2016, while the optimal instant of the loan flowing liberalization will be promoted from July to September 2011.
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Seeding uniformity is an important factor to evaluate performance and quality of
seeders. The comprehensive seeding accuracy testing method proposed in this dissertation
to test performance of precision seeder, grain drill seede...
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Seeding uniformity is an important factor to evaluate performance and quality of
seeders. The comprehensive seeding accuracy testing method proposed in this dissertation
to test performance of precision seeder, grain drill seeder, hill-drop planter, seeding monomer,
and seed sowing device is an integrative one with technology of computer vision, patter
recognition, and automatic control.
Construction method of dynamical image acquisition is studied. Sequential images matching
and splicing technology is studied. Begin with real-time requirement of dynamical testing,
image splicing problem is further researched and principle of image splicing is expounded. A
new sequential images sub-splicing method is proposed. Automatic control technology of the
test-bed is studied. System is coordinated controlled based on serial communication between
the computer and PLC. Measuring error is overall analyzed. Seeder performance testing
theory and method proposed is the dissertation have been used in real tests, which conforms
to Chinese standard of GB/T6973-1986，GB/T9478-1988. The testing error is less than 2
mm.
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