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A compact and tunable micro-integrated extended cavity diode laser (ECDL) on AlN ceramic template in butterfly packaging has developed for rubidium (780.2 nm) atom interferometry. Moveable parts are strictly omitted to provide maximum mechanical stability and reliability. The micro-integrated ECDL uses a volume holographic Bragg grating (VHBG) with a diffraction efficiency of 20% at 780.2 nm and a FWHM bandwith 70 pm based on a littrow configuration possessing an extended cavity length of 5.5 mm. The gain chip in ECDL has curved stripe with high reflecting (99%) on normal side and deep antireflecting (AR) on the tilted one. The curved stripe together with deep AR-coating provides extremely low reflection ( 65 GHz for a temperature range of 25 K with a tuning factor at 2.6 GHz/K. Continuous laser frequency tuning is achieved by sweeping the injection current to the Gain chip for 8.8GHz at -557 MHz/mA. The device provides a short term full-width-half-maximum (FWHM) linewidth of significantly less than 100 kHz and an optical power in excess of 120 mW.

This article uses semiconductor simulation software to simulate the composition concentration and thickness of the epitaxial structure of the InGaAsP near-infrared single photo avalanche detector. By optimizing and adjusting different parameters, this study manifests the ideal inner energy band, electrical field distribution, making the overall performance of the SPAD has been improved. The calculation results of I-V curve show that by controlling the thickness of the charge layer and multiplication layer within a certain range, the punch voltage and avalanche voltage of the device can be appropriately reduced to 25V and 72V, and the maximum multiplication factor can be obtained over 10000 under the avalanche voltage. By depicting the infrared spectrum response curve, it can be seen that in the range of 0.9 to 1.55um, the internal quantum efficiency of the SPAD is basically maintained above 70%, indicating that the device has a high photon conversion efficiency and meets the demand for single-photon detection.

Due to the lack of the urban household registration or property owner, many residents of urban residential areas in China have been in the state of lack of rights. The policy of "Equal rights for home tenants and owners" cannot play a practical role due to the lack of legal norms. "Home ownership" and "Right of residents" contain different contents. That is, "equal access to basic public services and social welfare of the place of residence, as well as the right to participate in decision-making, management and supervision of public affairs in residential communities and residential areas due to the fact of stable residence." The rights of the occupants is different from housing right and habitation right. The right of the occupants has not only legal basis, but also practical basis.

Optical waveguide phased array has a lot of benefits, such as high speed scanning, low control power, low optical loss, small package size and high integration and so on. Many fields including pilotless driving, celestial navigation，medical diagnosis, optical communication, can use this new type of all solid scanning device to improve their performance. In this paper, we conduct the theory simulation about the device design of the silicon waveguide phased array system and the main contents include these following researches. Firstly the simulation results about the local optical field under the TE mode of silicon optical waveguide based on SOI prove that our silicon-based optical waveguide has low electromagnetic wave loss. Secondly the input grating coupler for spatial light-towaveguide transmission is designed and the propagation direction and intensity distribution of the light field in the grating coupler are obtained, which indicates the coupling efficiency is more than 50%. Also the multi-mode interferometer structure design and optimization for multi-element phased array beam splitting are carried out, and the output intensity reaches 90%. Finally, the power of the heating electrode Ti is designed to meet the temperature requirement of phase shift at 360K.

Internal jugular phlebectasia is a rare condition. Children with internal jugular phlebectasia are often discovered by their parents when they notice a soft mass in the neck that appears when the child cries, coughs, or breathes deeply. Most internal jugular vein dilatations occur unilaterally on the right side according to the literature reports. To our knowledge, no other internal jugular phlebectasia patients reported pulsatile tinnitus as the major complaint without a soft mass in the neck. The authors reported a female adult patient with left-side internal jugular phlebectasia with pulsatile tinnitus as the major complaint without a soft mass in the neck. Internal jugular phlebectasia was diagnosed by color ultrasound of the internal jugular vein. Pure-tone audiometry, tympanometry, hemoglobin, thyroid function, and magnetic resonance imaging were made to differentiate other diseases that can cause the pulsatile tinnitus. Conservative treatment is recommended in this report. The possibility of internal jugular vein dilatation should be considered when differentiate the possible diseases that caused pulsatile tinnitus.

The GaN/AlN QDs with different height and density are grown by MOCVD in Stranski-Krastanov (S-K) method. The growing of self-assembly GaN quantum dots (QDs) in S-K method is attributed to six key growth parameters of Ⅴ/Ⅲ ratio, growth interruption, growth duration, flow rate, growing temperature and the NH3 protective atmosphere during cooling down. The surface free energy and GaN deposition amount on the growth front are modulated by adjusting the 6 conditions in epitaxial process of GaN QDs. The influence of the six growth factors on GaN QDs and the mechanism of which are systematically analyzed, the appropriate growth windows of each factor are obtained by optimizing experiments. The uncapped GaN QDs possess excellent photoluminescence performance.

Tripping off of the centralized grid-connected large-scale wind farm will have an impact on the grid frequency. When a failure occurs nearby the point of common coupling, in order to ride through the fault, it's a feasible strategy to turn the wind farm into isolated island operation for a short time and reconnect to the grid after the fault isolation. In order to achieve the condition for grid-reconnection, the frequency control characteristics of wind farms are analyzed in this paper and a reasonable short-term emergency control strategy of isolated island is proposed using the equivalent inertia. Furthermore, a simulation is carried out to verify the correctness of the strategy.