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From the perspective of travel insurance, this paper combines travel insurance and blockchain technology to design a travel insurance system based on blockchain technology. This paper first analyzes the existing problems related to travel insurance, and then further studies the core technologies of blockchain applied in this system, such as equality network, Byzantine consensus mechanism, asymmetric encryption and intelligent contract. Then the model of travel insurance system based on blockchain is established, and the architecture, function and process design of the system are carried out. Finally, the system is evaluated and extended from the single travel insurance to the whole insurance industry, and the combination of block chain technology and insurance industry innovation is summarized and prospected.

This paper mainly studies the EEG signals, eye movement signals, ECG signal analysis under natural humancomputer interaction and the fusion of multiple information sources to generate decision signals to judge whether the driver is fatigued or not. It is mainly used to automatically monitor the driver’s mental state in real time while the vehicle is running. Alerts when the driver just shows signs of fatigue. Forced deceleration or even forced parking in the event of a dangerous situation. The analysis of EEG signals mainly includes EEG signal acquisition, feature extraction and classification. The analysis of eye movement signals mainly includes face detection, human eye positioning, pupil and eye angle detection, etc. Integration and implementation mainly include the integration of multiple information sources, decision signal transmission, and fatigue driving monitoring system design.

In order to improve performance assessment participation, we need to add a new module for management performance appraisal system. However, the traditional performance appraisal is too programmed, the lack of interest. In order to solve this problem, this paper combines the advantages of performance cloud and mobile game, and designs and develops a performance game management software. It is based on the SaaS cloud platform. According to business needs assessment indicators to quantify, for the completion of basic performance appraisal module. Then, choose a mature SaaS vendors, designed a fusion of performance and gaming cloud platform. Then, scene settings are made for the newly added game module, and a performance game credit system and a challenge system are added respectively. Finally, with the mobile phone as the carrier, the system is spread through APP. In order to test the practicability of the system, the author put the application into a fire-fighting equipment enterprise for testing, and collected and analyzed the data of the sales department of the fire-fighting enterprise. The results showed that the system improved sales performance in the sector, and improve employee participation.

How to effectively control data access rights in the medical field and securely share data between hospitals is an important challenge in the standardization of medical information in China. This paper proposes a model of data access and secure sharing by using the decentralization, tamper resistance and traceability of blockchain. The system utilizes attribute-based encryption technology to ensure the authenticity of information and solve the problems of information asymmetry in the traditional medical field, difficulty in information inquiry, difficulty in positioning of responsible persons, and inability to trace information.

Vector beams (VBs) are widely investigated for its special intensity and polarization distributions, which is useful for optical micromanipulation, optical micro-fabrication, optical communication, and single molecule imaging. To date, it is still a challenge to realize nonlinear frequency conversion (NFC) and manipulation of such VBs because of the polarization sensitivity in most of nonlinear processes. Here, we report an experimental realization of NFC and manipulation of VBs which can be used to expand the available frequency band. The main idea of our scheme is to introduce a Sagnac loop to solve the polarization dependence of NFC in nonlinear crystals. Furthermore, we find that a linearly polarized vector beam should be transformed to an exponential form before performing the NFC. The experimental results are well agree with our theoretical model. The present method is also applicable to other wave bands and second order nonlinear processes, and may also be generalized to the quantum regime for single photons., 8 pages, 3 figures

Spiral phase contrast is an important and convenient imaging processing technology in edge detection, and a broader field-of-view (FOV) of imaging is a long-pursuing aim to see more regions of the illumination objects. Compared with near-infrared (NIR) spectrum, the up-conversion imaging in visible spectrum benefits from the advantages of higher efficiency detection and lower potential speckle. FOV enhanced and spiral phase contrast up-conversion imaging processing methods by using second order nonlinear frequency up-conversion from NIR spectrum to visible spectrum in two different configurations are presented in this work. By changing the temperature of crystal, controllable spatial patterns of imaging with more than 4.5 times enhancement of FOV is realized in both configurations. Additionally, we present numerical simulations of the phenomenon, which agree well with the experimental observations. Our results provide a very promising way in imaging processing, which may be widely used in biomedicine, remote sensing and up-conversion monitoring., 11 pages,5 figures,22 references

Heralded single-photon source (HSPS) with competitive single photon purity and indistinguishability has become an essential resource for photonic quantum information processing. Here, for the first time, we proposed a theoretical regime to enhance heralded single-photons generation by multiplexing the degree of the freedom of orbital angular momentum (OAM) of down-converted entangled photon pairs emitted from a nonlinear crystal. Experimentally, a proof-of-principle experiment has been performed through multiplexing three OAM modes. We achieve a 47$\%$ enhancement in single photon rate. A second-order autocorrelation function $g^{(2)}(0), 8 pages and 5 figures.To appear in PRA

In order to solve the shortcomings of coal mine enterprises in gas safety management, according to the big data theory, a safety management analysis method is proposed. First, the behavioral safety theory is used to classify the causes of gas hazards. Then use the HDFS to storage the unsafe behavior and unsafe physical state that found by behavior observers, and finally use the MapReduce-based parallel FP-growth algorithm to find out the repeated and dangerous unsafe behaviors in daily operations, and form a Hadoop-based gas behavior security management model. The experimental results show that the model has certain practical reference value for the targeted implementation of gas safety management in coal mine enterprises. Through the unsafe behavior and physical state found, the shortcomings in safety management will be discover, it will help enterprises improve the safety management system. So it has certain prospects for improving the safety production culture of coal mine enterprises and reducing the occurrence of gas accidents.

A 1632-nm laser has highly important applications in interfacing the wavelength of rubidium-based quantum memories (795 nm) and the telecom band (typically 1550 nm) by frequency conversion in three-wave mixing processes. A 1632-nm laser source based on pump-enhanced difference frequency generation is demonstrated. It has 300 mW of output power, in agreement with simulations, and a 55% quantum efficiency. An average power fluctuation of 0.51% over one hour was observed, and 200-kHz linewidth was measured using a delayed self-heterodyne method., Comment: 7 pages, 5 figures, accepted by Journal of the Optical Society of America B

The infrared imaging detection is an important and promising technology having wide applications. In this work, we report on the frequency up-conversion detection of an image based on sum frequency generation in a nonlinear crystal with a flat-top beam acting as the pump instead of a Gaussian beam, the up-converted image at 525 nm falls in the sensitive band of visible detectors and human eyes. Both theoretical simulations and the experimental results clearly demonstrate that using a flat-top beam as a pump can improve the fidelity of an image after the up-conversion compared with a Gaussian pump beam. Our scheme will be very promising for infrared image detection based on frequency up-conversion., Comment: 7 pages, 4 figures, accepted by Optics Communications

Entangled sources are important components for quantum information science and technology (QIST). The ability to generate high-quality entangled sources will determine the extent of progress in this field. Unlike previous schemes, a thin quasi-phase matching nonlinear crystal and a dense-wave-division-multiplexing device are used here to build high-quality versatile photonic sources with a simple configuration that can be used to perform Hong-Ou-Mandel interference, time-energy entanglement and multi-channel polarization entanglement experiments. The measurement results from various quantum optical experiments show the high quality of these photonic sources. These multi-functional photonic sources will be very useful in a variety of QIST applications.

The interferometer is one of the most important devices for revealing the nature of light and for precision optical metrology. Although many experiments were performed for probing photon behavior in various configurations, a complete study of photon behavior in a birefringent interferometer has not been performed, to our knowledge. By using an environmental turbulence immune Mach-Zehnder interferometer, we observe tunable photonic beatings by rotating a birefringent crystal versus the temperature of the crystal for both the single photon and two photons. Furthermore, the two-photon interference fringes beat 2 times faster than the single-photon interference fringes. This beating effect is used to determine the thermal dispersion coefficients of the two principal refractive axes with a single measurement: the two-photon interference shows superresolution and high sensitivity. Obvious differences between two-photon and single-photon interference are also revealed in unbalanced situations. In addition, the influence of the photon bandwidth on the beating behaviors that come from polarization-dependent decoherence is also investigated. Our findings will be important for better understanding the behavior of two-photon interference in a birefringent interferometer and for precision optical metrology with quantum enhancement.

Silicon-on-chip photonic circuits are among some very promising platforms for generating nonclassical photonic quantum state, because of its low loss, small footprint, and compatibility with complementary metal-oxide-semiconductor (CMOS) and telecommunications techniques. Dense wavelength division multiplexing (DWDM) is a leading technique for enhancing the transmission capacity of both classical and quantum communications. To bridge the frequency gap between silicon-chip and other quantum systems, such as quantum memories, a quantum interface is indispensable. Here, we demonstrate a quantum interface for multiplexed energy-time entanglement states, which are generated on a silicon micro-ring cavity that is based on frequency up-conversion. By switching the pump wavelength, energy-time entanglement from any channel can be selected at will after being up-converted. The high visibilities of two-photon interference over three channels after frequency up-conversion clearly prove that the entanglement is fully preserved during the quantum frequency conversion (QFC) process. Our work provides new perspectives regarding channel capacity enhancement in quantum communications and for quantum resources being transferred between two different quantum systems.

The ultimate goal of quantum information science is to build a global quantum network, which enables quantum resources to be distributed and shared between remote parties. Such a quantum network can be realized using only fiber elements, thus deriving the advantages of low transmission loss, low cost, scalability, and integrability through mature fiber communication techniques such as dense wavelength division multiplexing. Hence high-quality entangled-photon sources based on fibers are in high demand. Here we report multiplexed polarization- and time-bin-entangled photon-pair sources based on the dispersion-shifted fiber operating at room temperature. The associated high quality of entanglement is characterized using interference, Bell's inequality, and quantum state tomography. The simultaneous presence of both types of entanglement in multichannel pairs of a 100-GHz dense wavelength division multiplexing device indicates a great capacity in distributing entangled photons over multiple users. Our design provides a versatile platform and takes a big step toward constructing an all-fiber quantum network.

It is an effective way to mask the impact of the churn of services and task of integrating, conforming and scheduling heterogeneous, distributed resources from multi-domains based on virtualization. In order to implement and validate this approach, a service model based on virtualization has been provided, which include virtualization service layer, business rule editor, and business process management. Business rule is a useful tool to manage the business process through the separation of business and services. An extended event-condition-action rules has been provided and an example shows it will work well on basis on virtual services layer.

A novel frequency selective surfaces (FSS) based on Y-loop fractal element is investigated using finite difference frequency domain (FDFD) method and verified with experiment in this paper. Numerical and experiment results show that the Y-loop fractal FSS has the advantages of low insertion loss in pass-band, good frequency selectivity and stability of bandwidth etc. Its performance is very stable at various incident angles and different polarization state. Besides, because over 90% of the surface covered with metal, the Y-loop fractal FSS obtains very high IR reflectivity, so the proposed FSS can also be used in MMW/IR compound system as dichroic beam combiner.

With the rapid development of Chinese capital market in the last 18 years, recently the quality of accounting information of listed companies, which is crucial for the sustainable improvement of the capital market efficiency, has become the focus issue to investors, scholars and government. The main purpose of this paper is to test and explore the relationship between corporate ownership structure and quality of accounting information of China's listed companies. This paper extends earlier research with focusing on a particular industry, the manufacturing industry. This study uses 32 listed companies in the manufacture industry punished by China Securities Regulatory Commission (CSRC) for their financial statement fraud (FSF) during 2002 and 2006, and employs the method of descriptive statistical analysis, correlate analysis and logistic regression analysis, in which the total assets are used as the control variable, to examine the relationship. The results indicate that the higher the proportion of state owned shares and the lower the proportion of tradable shares, the more likely FSF to happen. This study also finds that FSF is even more frequent for companies with State Assets Management Bureau as the biggest shareholder.

To transform the cities that have resource-dependent development into cities with diverse economic growths is a comprehensive and complex system project. Baishan City, as a typical example of the cities which rely on resources for economic developments, has made remarkable achievements in the economic, social and ecological transformations and urban functions upgrade, overall government administration improvements. The industrial transformation, new project introduction, technological innovation support, people life's improvement and stabilization, urban development and social security improvement initiated by Baishan city cannot only provide a lesson for the transformations of other resource-based cities but also serve as a positive example for our country to carry out the national strategic change in the economy growth pattern.