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The Sn-ball integrated with the QDLED package are designed to achieve more effective heat dissipation. The thermal, luminescence and aging tests of this structure were evaluated and was proved that have good CCE and reliability.

The establishment of functional neural networks has been extensively studied in vitro. Various patterned substrates based on micro-nano processing and fabrication technology are used to control the connection mode of neurons. In this study, unidirectional arranged and radial arranged diphenylalanine (FF) nanotubes are made for the cultivation of hippocampal neurons. The two different FF nanotubes patterned substrates produced in this article induced two different behaviors of hippocampal neurons. Directional arranged FF nanotubes can induce the directional arrangement of neurons. The directionality of neurons can be maintained even after FF is dissolved. On the other hand, neurons quickly migrated into clusters under the induction of radial FF nanotubes and further form a complex patterned connection network. The method proposed in this paper can be used to study various behaviors of neurons, and further can be used to study the different patterned structures to construct different neural network types.

This paper compared air gap and tolerance voltages correction methods on high altitude area, and based on them we analyze correction method considering the special environmental conditions of Sichuan-Tibet railway. With test results of short air gap in different areas of China, we verified the adaptability of insulation gap correction method at an altitude of 4000 to 4500m. As a result, we formulated a correction method and value of air external insulation under 50Hz overvoltage and lightning impulse overvoltage of 27.5kV traction power supply system at an altitude of 4000m to 4500m.

Screening of new anticancer drugs and personalized medicine are of great significance for improving clinical cancer treatment and prolonging the lifespan of people diagnosed with cancers. Cell-based drug testing approaches that rely on complicated electrophysiological measurements or chemical activators and reporters are usually invasive and low throughput, therefore it is very imperative to develop an easy handling and efficient method to evaluate the efficacy of anticancer drugs. In this study, we present a simple and efficient method for pharmacodynamic evaluation based on optogenetics and graphene-based field-effect transistors (GFETs). This method involves the fusion of optogenetically engineered cancer cells and a GFET, in which the photoinduced bioelectricity of cells regulates the transistor output current. The experimental results showed that the light-dependent increment in the transistor output current of GFET falls dramatically upon the action of drugs, indicating the GFET with engineered cells can be used to evaluate drug efficacy. In addition, the drug efficacy evaluation with GFET is affected by the drain-source voltage, and the experimental results showed that drug efficacy can be better characterized at an appropriate drain-source voltage. These results demonstrated that the proposed method is effective and efficient for qualitative evaluation of drug efficacy. This method based on optogenetics and GFET is of significant value in drug screening and personalized therapies.

In this paper, a new five-band compact coaxially fed microstrip patch antenna is proposed, with a profile consisting of a serrated pattern, and a shape of a leaf of a poplar tree. The DGS(Defected Ground Structure)is created by using a combination of multi-loop nesting and rectangular branching. The proposed antenna has 5 impedance bandwidths which span in the range of 1. 70-1. 74, 3. 38-3. 43, 5. 16-5. 29, 5. 46-5. 63 and 7. 17-7. 38 GHz respectively. The antenna proposed in this paper can effectively cover the WLAN / Wi-Fi / WiMAX frequency bands. This antenna works in coaxial feed mode and has the advantages of multi-band, miniaturization, low material cost, easy processing and realization. It has a broad prospect in the field of LOT application research.

In this communication, a triband AMC-backed microstrip antenna is designed. It is implemented by placing a triband microwave antenna which uses coplanar-waveguide (CPW) over a novel artificial magnetic conductor (AMC) with three zero-phases in the reflection coefficient. The AMC unit cell is composed of three homocentric copper rings. The simulated S-parameters generally corresponds to the performance of original antenna without AMC. The return loss of the frequency range 2.4GHz which can be used for WLAN is enhanced. By adjusting the distance between the antenna and the AMC plane, the performance near 1.8GHz can be optimized.

Spatial source phase (SSP), derived from complex-valued functional magnetic resonance imaging (fMRI) data by data-driven methods, has unique capacity of identifying blood oxygenation-level dependent (BOLD)-related voxels from noisy voxels regardless of their amplitudes. However, the use of SSP constraint in sparse representation algorithms have rarely been studied. This study proposes a sparse representation method using SSP hard thresholding to achieve the sparsity of spatial components, enabling the use of initially complex-valued fMRI data and retaining the brain information embedded in noisy voxels and weak BOLD-related voxels with small phase values. Rank-1 matrix estimation is applied to sequentially update dictionary atoms and corresponding spatial components, followed by hard thresholding on spatial components based on SSP. The proposed method is evaluated using both simulated and experimental complex-valued data. The results show that the proposed method yields better performance than a complex-valued dictionary learning algorithm when using initially acquired complex-valued task-related fMRI data.

With the development of artificial intelligence and big data technology, people are paying more and more attention to its application in eco-tourism marketing. To make better use of big data for eco-tourism marketing, and analyze and meet the psychological needs of tourists, this article uses some artificial intelligence algorithms, including analytic hierarchy process and fuzzy comprehensive evaluation model, to evaluate rural eco-tourism options and put forward suggestions for constructing firefly eco-tourism.

As an important part to ensure the normal operation of the boiler, the defect detection of water walls based on the internal surface information of water walls has been paid more and more attention. But the traditional manual detection method is time-consuming and laborious with the low efficiency. Therefore, an intelligence detection method for detecting water wall defects in boiler systems based on the convolutional neural network (CNN) is proposed. The CNN has the characteristics of local connection, weight sharing, pooling and multi-layer structure, which can effectively extract local features of the water wall to build the intelligence defect detection model. Finally, the proposed method is used in the defect detection of the water wall of an actual thermal power plant. The experimental result has proved the effectiveness of the proposed method, And the recall rate and identification speed of the proposed method can meet the requirements of intelligent detection of the water wall defects.

A quad-AMC-backed multi-band antenna system is designed in this paper, which is characterized by high gain and low profile, for the application in the frequency bands of 1.74, 2.41, 2.96, 3.86, and 5.07 GHz. Among them, the operating frequency point of this system is about 2.96GHz, which is new frequency point compared to the single antenna. The measured antenna gains at the frequency points have been improved with 3.2, 3.3, 2.16 and 1.5 dB, respectively. As an asymmetrical antenna structure is designed, SMA terminals are introduced in the simulation in order to get closer to the real measured results. The distance between antenna and SMA proposed in this paper is only 3mm, which is more conducive to the application in 5G mobile communication systems, the interconnection of all things (IOT) and in other fields.

In this paper, a quad-band microstrip antenna is designed by adding some narrow strips on the patch and some notches on the ground acting as resonance paths to realize multi-band. The bandwidth of the antenna covers the 2.4/5.8-GHz WLAN frequency bands and the 2.5/3.5-GHz WiMAX bands. To improve its performance, an artificial magnetic conductor (AMC) characterized with four zero-phases in the reflection coefficient is proposed. The zero-crossing phase points of the AMC correspond to the antenna's operating frequencies. Splicing the AMC unit into a 5*5 matrix and placing it under the antenna as a reflector, the measured antenna gains have been improved by 5.91, 2.7, 3.0, 5.4dB respectively.

In this paper, a dual broadband antenna with simple structure is designed, which is developed from the traditional rectangular microstrip antenna. It is suitable for the frequency band of 2.19-3.20GHz and 5.72-7.95GHz. In order to improve the radiation performance of the antenna, an uncomplicated structure of artificial magnetic conductors (AMC) with two zero crossing phases, which are consistent with the antenna structure, are developed. The AMC unit is composed of metal rings with characteristic reflection coefficients of 3.2 and 7.95 GHz. ${5\times 5}$ AMC cell arrays are fabricated and measured to work together as reflectors and antennas. Compared with the antenna without AMC, it is observed that the proposed AMC can not only greatly increase the antenna gain, but also further increase the bandwidth of the antenna. The gain of the antenna supported by AMC is enhanced by 5.9, 5.3, 3.6, 5.3 and 5 dB at 2.5, 3, 6, 6.6 and 7.6 GHz, and the frequency band is widened to 1.14-3.13 GHz and 5.69-7.96 GHz. It can be seen that the proposed antenna effectively covers multiple communication bands, and its structure is so plain that it can be easy to manufacture. Therefore, it can be potentially applied to mobile communication systems in WLAN, WiMAX and 5G.

In this paper, a multi-band AMC-backed microstrip antenna system characterized with high gain is designed. It is constructed by placing a quad-band antenna over an artificial magnetic conductor (AMC) with five zero-phases in the reflection coefficient. The multi-band antenna consists of a neoteric shaped patch with the specially designed parasitic slots, and a defected ground structure (DGS), for the application in the frequency bands of 2.2, 3.7, 6.9, 9.3GHz. To improve the antenna's radiation performance, an artificial magnetic conductor (AMC) ground with five zero-phases of the reflection coefficient is designed and employed as the reflector. The prototypes of the antenna and the AMC array with 5×5 unit cells were fabricated and measured. It is found that in comparison to the antenna without AMC, the AMC-backed antenna obtains a gain enhancement by amounts of 4.93, 5.92, 5.54 and 4.95 dB at the frequencies of 2.2, 3.7, 6.9 and 9.3 GHz. The 10-dB impedance bandwidths of the AMC-backed antenna include four bands of 2.28-2.52, 3.80-4.42, 6.14-6.93 and 7.41-7.81 GHz, The proposed antenna system can be potentially applied to the applications in 5G mobile communication systems.

In this paper, a multi-band antenna composed of irregular metal plate, input feeders and symmetrical defect ground is designed. The antenna radiation enhancement is improved by placing a rectangular artificial magnetic conductor array with zero phase reflection points corresponding to the multi-band antenna frequencies at a fixed distance below. The three impedance bandwidths of the antenna are 2.13-2.58GHz, 3.43-3.64GHz and 5.7-6.0GHz respectively, which effectively cover the 2.4/5.8GHz WLAN band and 2.5/3.5/3.8GHz WIMAX band. By adding AMC reflector, the performance of the antenna in the working frequency band is significantly improved, and a new frequency band is generated at 7.54-8.63 GHz.

Due to the low level of college students' professional quality and low employment rate, in recent years, enhancing the extracurricular learning ability of college students has become an urgent problem to be solved in college education. Based on learning resources and its influencing factors, this article studies the selection of extracurricular learning channels for college students through Analytic hierarchy process (AHP) and Grey association analysis, aiming to improve the extracurricular learning efficiency of college students and provide references for making policy.

Aluminum melting process is a semi-continuous process with high-energy consumption. In this paper, a software-based strategy which considers numerical simulation and control scheme simultaneously is employed to improve energy consumption of aluminum melting furnaces without changing the hardware. For numerical simulation, a nonlinear steady-state optimization is performed offline to obtain optimal operating points. Extensively, the optimal operating conditions include not only product exit temperature, but also ratio of combustion air flow and natural gas flow, furnace temperature, flue gas temperature and some important manipulated variables. For control scheme, a two-layer model predictive control which consists of steady state target calculation and dynamic optimization is developed to track the optimal operating conditions. In steady state target calculation layer, a priority strategy is proposed based on the different importance of controlled variables to make the steady state targets more reasonably. In dynamic optimization layer, a quadratic objective function is defined in terms of tracking both the optimal steady-state of controlled variables and manipulated variables. The method is successfully carried out in F1 aluminum melting furnace of a company in Tianjin. Compared with previous operation, the comprehensive energy consumption and the comprehensive energy consumption for unit output of product decrease 5.99% and 6.56% respectively.