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This paper firstly describes present situation of Aerospace engineering application and Space TT&C Network in brief, in which the business process of Space mission is analyzed and the problem why it is weak at the command control of the command center at all levels is pointed out. Then the functional requirement including six aspects: resource management, comprehensive situation, task planning, command control, analysis evaluation, is studied, and the command control system architecture of space TT&C network with five layers and two vertical layers is designed.

This paper presents the multi-mode control strategy and power management for a novel three-port DC-DC converter (TPC) for photovoltaic (PV) electric vehicles. The TPC consists of a PV module, a battery, a boost converter, two single ended primary inductor converters (SEPIC) and a load. It achieves maximum power point tracking (MPPT) of PV module. It has the advantages of charge-discharge control of battery, voltage control of load and any two ports can realize power flow. According to the PV module power and the state of charge (SOC) of the battery, the TPC can be judged to operate in which working mode, so as to realize the continuous and stable power supply to the load. In this paper, the TPC was simulated by Matrix Laboratory (MATLAB). And the simulation results proved the feasibility of the proposed TPC.

the negative database (NDB) is a new type of privacy protection and data security technology, which enhances the security of the data by storing the compressed form of the original data complement, thereby achieving the protection of privacy data. In practical applications, each record in the original database (DB) is usually transformed into a negative database to obtain negative database NDB s to achieve the protection of privacy data. Then, use the classification and clustering methods on the negative database are used to mine and analyze the privacy data. The DBSCAN clustering algorithm is a classical density-based clustering algorithm, and the Euclidean distance formula is one of the most commonly used distance measurement formulas in the clustering algorithm, and the DBSCAN algorithm is of no exception. However, the current Euclidean distance measurement of DBSCAN clustering algorithm is based on the distance measurement of plaintext data, so it is impossible to cluster the privacy data transformed into negative database. In this paper, we introduce a DBSCAN clustering algorithm based on the Euclidean distance formula on a negative database, which is used to complete clustering research while protecting privacy data. The experimental result showed that our algorithm achieved high clustering accuracy and effectively protected the security of privacy data by using irreversible negative database. Therefore, the algorithm we designed is very effective and feasible.

A microfluidic channels chip and its processing method and application are introduced for Terahertz (THz) absorption signatures detection of biomolecules in aqueous solution. Thousands of rectangular microchannels with a characteristic dimension of 2 μm and their reservoirs were precisely etched in a high resistivity silicon wafer by lithography and etching process, then the silicon wafer and a glass sheet were bonded to form a sealed microfluidic chip by anodic bonding technology. The chip can be sampled through the capillary action and the microfluidic pressure system. Three absorption signatures around 850, 928, 950 GHz of dissolved λ-DNA were obtained in 0.7∼1.0 THz band by using this chip and the coherent photomixing spectrometer. It is indicated that dispersion of biomolecular solution in 2 μm spaces between the tines of the grating in microchannels can reduce the water component in THz transmission detection, thereby reducing the water background absorption, effectively improve the signal strength of THz characteristic attenuation.

DNA mutations are analyzed by terahertz (THz) spectroscopy in a label-free manner. The 5 base mutations from the 3'-terminus on single stranded 17nt oligonucleotides have first been detected based on the microchannel. The mutations have also been validated based on the split-ring resonators (SRRs). The results clearly demonstrate the ability of THz spectroscopy combined with microstructure for label-free detection of base mutations of DNA biomolecules. This study has proved that the THz spectroscopy can be considered as a prospective diagnostic tool for studying the interaction of molecules such as DNA mutations.

Fluidic chips as sample storage devices have been widely used to control and analyze traces of solutions by terahertz time domain spectroscopy (THz-TDS). This paper presents a fluidic chip fabricated with ultra-thick micro-fluidic structures utilizing SU-8 photoresist for THz spectral detection. The chip consists of 2 pieces of quartz windows and a photoresist structure serves as liquid cell between the windows. In order to reduce the attenuation of THz energy by the windows and guarantee measurement stability, an infrared quartz with thickness of 1mm is adopted as the windows. For the purpose of improving the signal-to-noise ratio (SNR) in the frequency band between 1.0 THz-1.5 THz, and making the liquid film thickness match the THz optical path, the structure depth is designed to be 50μm. Water absorption coefficient at 0.1THz-1.5THz was detected with this chip. The result indicates that the chip has a good stability for terahertz spectral detection.

4H-SiC avalanche photodiode with a separated absorption region, a charge adjustment region and a multiplication region is proposed and its optoelectronic performance is modeled. By properly designing the doping concentration of each layer, the avalanche breakdown voltage and photo-response of the device is found to be dependent of the thickness of the multiplication region. The avalanche breakdown voltage shows a minimum and the photo-response shows a maximum at certain thickness of the multiplication region. The results are explained by the electric field distribution of the device and the impact ionization theory.

Effects of Al ions implantation into n-type 4H-SiC followed by annealing at various temperatures have been studied by Atomic Force Microscopy (AFM), Raman scattering, Fourier transform infrared (FTIR) reflectance spectroscopy, and Hall effect measurements. AFM experiments observed a large amount of discontinuous strips on 4H-SiC surface running along three directions after high temperature annealing. Raman scattering and FTIR spectra jointly indicated the damage and amorphization of 4H-SiC due to Al implantation and the crystal restoration after high temperature annealing. Hall effect measurements revealed that the sample annealed at 1600 °C achieved a higher activity ratio and a lower resistivity, which satisfied the application of numerous SiC-based devices.