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Washing machines, as common household appliances, consume a lot of domestic water. The working process of the traditional washing machine mainly includes washing, rinsing and dehydration. The rinsing water has low pollution level, but the consumption is large, accounting for more than 70% of the total water consumption, and the water resource utilization rate is low. Aiming at this problem, combined with water purification technology, a new carrier structure was designed by using 3D modeling software and the optical path design of the structure was optimized by COMSOL software. A ceramic wastewater based on photocatalytic reaction was fabricated by ceramic 3D printing technology. Processing device. Combining photocatalysis with ceramic 3D printing technology, design a photocatalytic reactor to improve water treatment efficiency, safe and no secondary pollution. Through the standard cloth washing water treatment experiment, it is determined that the pollution component in the laundry wastewater treated by the reactor is reduced, and the purification effect is obvious.

Intermediate joint is an important accessory equipment of power transmission cable, which connects several sections of cable as a whole, and the insulating property of cable accessory is the foundation of safe and stable operation of transmission cable. In view of the current situation of frequent partial discharge malfunction which occurs on high voltage transmission cable intermediate joint, the detection, disposal and analysis process of a new PD check method based on wireless communication is elaborated in this paper, and the measures which could prevent such malfunction and improve transmission cable operation reliability are proposed to be a reference for the operation and maintenance of transmission cable.

With the gradual extension of artificial intelligence applications in terminal equipment, intelligent terminals based on edge computing are also widely used in power systems. The new embedded terminal device with local decision function can process the collected raw data locally and only report the key information, which can reduces the requirement of network bandwidth, so makes the wireless transmission meet the needs of more business scenarios. In order to collect a large number of terminal data in time, traditional substations need high network bandwidth. The data can only be transmitted over wire. The data in new transformer substation with intelligent terminal can be aggregated by wireless transmission. But the data security of wireless networks such as IEEE802.11ah, LoRa , NBIoT and WiFi cannot be guaranteed. At the same time, with the needs of social development, data security has risen to the height of national security. In order to realize the "security and controllability" of information systems, China Cryptographic Administration has published a series of encryption and decryption algorithms such as SM2, SM3, SM4. In this paper, based on the IEEE802.11ah standard, we study the application of SM2, SM3 and SM4 in LAN of transformer substation, and mainly focus on the identity authentication, key distribution and data encryption and decryption. In view of the three different stages, the system scheme designs are proposed respectively, and then we analyze their security and the additional system overhead in detail. The research of the SM2, SM3 and SM4 algorithms in LAN of transformer substation will further promote the popularization and application of intelligent terminal in substaion, and this will also ehance the level of intelligence of substation.

Self-service assessment model for measuring severity of Parkinson's disease (PD) has recently received considerable attention due to the inconvenience and cost of physical visits to the medical clinic for PD patients. Previous works, however, mostly focus on the feature extraction and classifier design without considering notable intrinsic differences between patients with Parkinsonism (PWP), which has an adverse impact on generalization of model detecting PD. This paper introduces a novel PD-detected model based on Extreme Gradient Boost (XGBoost), where prior knowledge including gender and age are used to predict the severity of PD through unified Parkinson's disease rating scale (UPDRS). Firstly, using gender and age as a prior knowledge decomposes the prediction model of UPDRS to get new sub-model. Secondly, we obtain a regressor trained by XGBoost on the respective sub-model. Finally, we can get the final prediction about UPDRS using trained model. The experimental results show that our method significantly improves performance on the remote Parkinson dataset.

A wideband high efficient power amplifier(PA) with an integrated suspended substrate stripline (SSS) filter as its output matching network (OMN) is presented in this paper. Compared with classical PAs, the suspended substrate stripline filter replace the output match network, and the input impedance of the filter in this design is no longer $\mathbf{50 \Omega}$ , but a complex impedance. So that it can match the optimal output impedance of the PA directly. And then high efficient power amplifier can be obtained. Besides, a conventional OMN of the PA is eliminated entirely, which leads to a small size and low insertion loss. The filter is made up of microstrip half-wavelength stepped-impedance resonators and wrapped in a metal cavity. Thus, increasing bandwith and reducing the insertion loss. two controlled transmission zero is generated at the right side of the passband, resulting in high selectivity. Both theoretical analysis and measured results are presented for validation. The bandwith of the PA for more than 65% PAE is 340MHz at 2.45GHz, the maximum PAE is 76.6% at 2.28GHz.

T304 western mountainous area is rich in wind resources and has the weak network structure, multiple ice disasters, and the jumping of load under the participation of small run-off-stream hydropower. Therefore, a large number of diversified wind power generators have brought many problems to the regional power grids, among which the most serious issues are the drastic fluctuations of the grid voltage and the wind power grid economy problem under the influence of ice disasters. Since wind power stations are mostly located in mountainous areas, the network integration program has a great impact on the above problems. Based on adaptable comprehensive assessment index system and evaluation method, this paper studies the general framework and functional framework of a variety of intermittent energy grid integrated evaluation system, considering the risk of multi-point wind power network. Then use the trial-production multiple intermittent energy grid integration evaluation system to compare different plans. The results are of great significance to ensure the economy and safety of future grid operation.

I302 power supply access network increases the power capacity of system, improves the reliability of the system and reduces the power outage probability and lack of power supply. However, due to the randomness and volatility, the intermittent power output is difficult to control effectively. Therefore, intermittent power supply access distribution network planning has brought a series of new challenges to distribution network planning. This is always an urgent research topic about how to evaluate and decide the planning of distribution network with intermittent power. In this paper, a multi-index evaluation system of planning scheme including 7 second-level indicators and 20 third-level indicators was established, according to the characteristics of distributed generation and the structure of distribution network. Then apply this model to evaluate the distribution network planning scheme of a typical mountain, verifying the effectiveness and practicability of the evaluation system and evaluation method.

In order to maintain the quality of water resources in the global environment, we must conduct water quality monitoring. With the evolution of technology, we can improve the management of water quality by the IoT(Internet of Things) system. Therefore, this paper provides a real-time water quality monitoring system by the Internet of Things system. We selected Dong Lake in National Dong Hwa University as a test field to monitor water temperature, turbidity, conductivity, and pH. After that, the various water quality data will be transmitted to the database via wireless transmission. Finally, these data will be displayed on the web page immediately. And, it is very important to select what kind of wireless communication technique. For the long-range application in the field, we used Low-Power Wide-Area Network (LPWAN)-Long Range Wide Area Network (LoRaWAN) for data transmission. To extend the system life, a solar panel is adapted to recharge battery.

A set of GaN technologies are presented including a revised 0.25μm GaN HEMT technology in WIN Semiconductors' NP25 platform. The new improvements to the NP25 GaN HEMT were realized by the optimizing device layout, the fabrication process and the epitaxy enabling improved performance while still maintaining highly reliable operation for X-band applications. Pulse I-V shows low gatelag and drain-lag ratio of 16% and 6%, respectively. The maximum power-added efficiency (PAE) could be improved from 59.6% to 64.7% at 10GHz. The 0.45μm GaN HEMT technology for L-, C-, and S-band applications has 60.5 % PAE at 2.7 GHz. The 0.15μm GaN HEMT technology for Ka-band applications has PAE 39.6% and power density up to 5.4W/mm.

A rational and efficient tool is needed for the scheduling of public transport bus services that will satisfy the needs of passengers for different service time requirements. An intelligent urban bus system should not only be able to reduce carbon emissions and traffic congestion, but also to improve transport services. A model is proposed which computes Shapley values for seventeen different time periods in one day for a bus route. A fair allocation of buses based on the Shapley value is made which entails the minimum amount of deployment cost. This study applies data for the rapid transit bus system in the city of Xiamen in China to verify the Shapley value model. The simulation results show that management can easily use this framework to quantitatively allocate buses along routes within the seventeen time periods in one day and that the proposed approach is more efficient than current bus scheduling methods.

Guizhou Province is rich in water resources, in addition to large and medium-sized hydropower stations, but also has more than 3,600 MW of small hydropower, which accounted for 74.65% of small hydropower. In this paper, the existing small hydropower power forecasting method is analyzed. It is found that the existing forecasting methods have poor adaptability to the power prediction of the small hydropower station, and the precision is difficult to meet the dispatching operation requirement. The main reason for the above problems is that run-of-river small hydropower is mostly in remote mountainous areas. Power generation capacity is affected by climate and geographical environment seriously, which results in strong randomicity of power generation output. Finally, through the comparison and analysis of the actual data and the forecast data of the small hydropower station, it is found that the prediction accuracy of the small hydropower has a great relationship with the historical power data and the quality of the weather forecast. It is suggested that in the future research and engineering practice, forecasting the quality of the historical data and the weather forecast data should be fully considered to improve the forecast accuracy of the run-of-river small hydropower, so as to provide the basis for adjusting the operation plan of the grid dispatching and ensure the safe operation of the grid.

As a clean energy, small hydropower had developed rapidly in recent years. However, the generation characteristics of runoff small hydropower units were poor and had less regulation ability. These factors affect the operation of the power grid. Through the analysis, it is found that the long time scale precipitation has a strong correlation with the small hydropower output. It is volatile in summer when the rainfall is abundant, but has weak correlation with temperature and wind. Small hydropower has the cumulative effect and the hysteresis effect. This paper provides a reference for the analysis of small hydropower generation and grid connected operation, to achieve the purpose of full utilization.

A W band folded waveguide Traveling Wave Tube that adopts horseshoe-shaped attenuator and a periodic step-tapering folded waveguide slow wave structure is reported in this paper. In this Traveling Wave Tube, Reflection from severability was effectively reduced and self-oscillation was depressed, and also electronic efficiency is raised by about 1.5∼2% comparing with uniform periodic folded waveguide Traveling Wave Tube.

Rectangular packing problem is common in the manufacturing industry. It is essentially a NP hard combinational optimization problem. In this paper, a novel algorithm based on dynamic updating of packing point set is proposed to deal with rectangular packing problem. In the process of packing, we update the packing point set dynamically. After placing a part, we need remove the packing point that has been used and add the new points caused by placing this part. We can find the effective packing points quickly. Meanwhile, using this algorithm, we can easily fill the interspaces produced during the packing process. Based on the principles of hybrid intelligent algorithm, we synthesized the particle swarm algorithm (PSO) and genetic algorithm (GA) and presented an improved discrete PSO for optimizing the order of the parts. In this algorithm, we improved the diversity of the population and overcame the drawback of trapping in local minimum by refreshing the new particle through selection, crossover and mutation operation. The experimental results indicated that the algorithm of dynamic updating of packing point set and improved particle swarm optimization can meet the demand of engineering application by effectively improving not only the calculating precision and speed but also material utilization ratio.

As the requirements of smart grid for reliability and operational flexibility improving, construction and transformation of the distribution network have become frequent. However, drawing and maintaining the one-line diagram in manual way cannot satisfy the requirement because of its large workload and fallibility. This paper presents a method for automatic generation of one-line diagram of distribution network with multiple feeders. The method consists of two steps: generate the initial one-line diagram and adjust this diagram. In the first step, the directed edge-list and device information of the network are used as input, and the original topological graph is partitioned into feeders by removing the tie lines. Then we allocate sufficient drawing area for each feeder. Considering the effect of its adjacent feeders that have been generated and the new feeder will connect with, it is crucial to assign the optimal directions to branches. In the second step, the overlap and cross in the interior of each feeder will be eliminated. And in order to reduce the total area of the diagram, the space among the feeders will be adjusted and the longer branches will be handled. Finally, the experiments are conducted in the simulation system that we design and develop, and the results illustrate the method generates an excellent and readable one-line diagram of multiple feeders.

An original asymmetric coplanar (ACS)-fed filter which works in the ultra-wideband (UWB) frequency band is proposed in this article. This designed UWB filter by using a new structure brings out nice expressions like one transmission zero, which is benefit for the filter to have a sharp skirt near the 10.5 GHz. The bandwidth covers the whole UWB spectrum of 3–10.7 GHz, at the same time, the in-band insertion loss is less than 1.3dB by testing the UWB bandpass filter. The tested return loss has a good behavior, which is less than −10 dB in the passband. Moreover, the suppression is higher than 19 dB between 12.3 GHz and 19.5 GHz. The whole area of the filter is 17∗20 mm2.

It is analyzed the requirements of run-of-river small hydropower station group (RSHSG) short-term power forecast in this thesis. And the functions of short-term power forecast system is detailedly described from the software structure. Finally, selecting the data from April. 2016 and May. 2016, the application effectiveness of system is analyzed by comparing the accuracy both in time and space scale. The successful application of system in Guizhou Power Grid, has great significance in improving management level of grid dispatch and safe operation of the power grid.

In this talk, we present our recent work on controlling the polarization states of light with metastructures. First, we illustrate an approach to tune efficiently the phase difference of light in two orthogonal directions by controlling the time retardation with a microstructured surface. Second, we demonstrate the general mechanism to construct the dispersion-free metastructure, in which the intrinsic dispersion of the metallic structures is perfectly cancelled out by the thickness-dependent dispersion of the dielectric spacing layer. By selecting the structural parameters, the polarization states of light can be freely tuned across a broad frequency range, and all of the polarization states on the Poincare sphere can be realized dispersion free. Third, two examples are given: one is that we have achieved high-efficiency generation of circularly polarized light via symmetry-induced anomalous reflection in a metasurface; the other is that we have realized a freely tunable polarization rotator for broadband terahertz waves using a metastructure, which can conveniently rotate the polarization of a linearly polarized terahertz wave to any desired direction with nearly perfect conversion efficiency. The investigations provide some guidelines to control the polarization state of light at subwavelength scale.

A compact dual-band printed flltering antenna fed by CPW(co planar wave guide) is presented. Though printing on the same substrate board like as a conventional antenna, the proposed structure not only own the unit of radiator of the antenna, but also a second-order band-pass fllter, with two fllter poles provided by two rectangular -- circle with a stub. According to the fllter speciflcations, the antenna design process for the proposed flltering antenna is depicted in enough detail. And the operating bandwidth of the proposed antenna is broadened and high selectivity is also improved correspondingly. The measured results of the proposed antenna, including the S-parameters, total radiated power, current distributions and antenna gains versus frequency, have a very good agreement with the original design and simulation. The proposed novel antenna, with a very small area of 32.7×28.4 mm2, is single board structure and generates two usable resonant frequencies at about, 5.2(5.15-5.35), 5.8 (5.725-5.825) GHz for WLAN applications.

This paper presents a compact-size co-planar waveguide (CPW) -fed antenna for ultrawideband (UWB) applications. The feeding structure of the proposed antenna is a fork-shaped type, and the ground plane is an open-loop type made of two L-shaped extended ground plane stubs. The size of this proposed antenna is only 26 × 20 × 0.8 mm3. The simulated 10-dB return loss bandwidth is 0.17 GHz (3.1-17.0 GHz), and its corresponding gain along the desired band is 0.44-5.2 dBi .

In this paper, we present a 50V GaN HEMT technology portfolio and focuses on layout optimization, fabrication, and device modeling. A 100W PA has been demonstrated with custom heat-sink and second harmonic tuning. The newly developed 50V technology enables high power amplifier, pulsed radar, CATV, and LTE applications utilizing supply voltages of 50V for L- to C- band operational frequencies. Our pure-play GaN Foundry service supports RF MMIC and discrete device applications with comprehensive specifications and wafer acceptance tests.

A high-speed video camera was used to study the flow patterns in the rectangular channel of vertical upward cross-flow of air and water in horizontal tube bundles. Experiments were conducted using in-line tube bundles with a pitch-to-diameter ratio of 1.3 and 1.8. Bubbly flow, intermittent flow and mist flow were identified by flow visualization, and a flow map was constructed as a function of gas and liquid superficial velocities. The information of a single-frame was extracted and made into time series. The recurrence quantification analysis method was used to study the dynamic characteristics of information entropy of gas-liquid two phase typical flow patterns and transition flow patterns. The results show that the recurrence plot of entropy series of transition flow patterns shows the process of flow transition. The characterization result showed that the recurrence plot of information entropy could well reflect the evolution characteristics of flow pattern, and the recurrence characteristics quantities were sensitive to the variations of superficial gas velocity and provided an auxiliary tool for investigation of gas-liquid two-phase flow mechanism.

A comparative analysis of pressure drop of different flow pattern of two tube bundles was done. The results show that: the pressure drop of bubble flow is maximum, followed by intermittent flow, and mist flow becomes the minimum. Based on the statistical analysis of the different pressure signals, the power spectrum density versus frequency of the signals for major flow patterns was obtained. It is found that the flow patterns can be identified in accordance with the power spectrum density. The recurrence quantification analysis method was used to study the dynamic characteristics of differential pressure fluctuating signals of bubbly flow, intermittent flow, mist flow patterns. The research indicated isolated points texture appeared on recurrence plot for the bubbly flow. Both dispersed points texture and massive texture appeared on recurrence plot for the intermittent flow with strong chaos characteristic. The recurrence plot of mist flow whose idicated periodic is outstanding has a good diagonal texture. The recursion texture of differential pressure fluctuating signals could well reflect the evolution characteristics of flow pattern, and the recurrence characteristics quantities were obvious to the variations of superficial gas velocity and provided a new idea for investigation of gas-liquid two-phase flow mechanism.

With the rapid development of economy, numbers of power grid projects are multiplying yearly. Power supply companies are more and more concerned about how to plan these projects. In order to optimize the power grid project portfolio objectively and comprehensively, a scientific indicator system is constructed by analyzing the characteristics of power grid projects. The valuation of each project is evaluated accurately on the basis of analytic hierarchy process with the indicator system. Many additional factors need to be considered in process of investment portfolio optimization of power grid project, such as the limited total funds and the limited allocated funds of subsidiaries. So niche genetic algorithm is adopt to optimize the model and obtain satisfied solution of investment portfolio of power grid projects. Experiment results show that the performance with this approach is more promising and it can make the project investment portfolio more reasonable and practical.

A hash chain is a popular tool for improving the efficiency of several cryptographic applications. In spite of the computation efficiency of one-way function, the performance issue is a challenging research topic for chains with long length in resource-constrained environments. We propose a recursive algorithm of hash chain traversal for arbitrary length n with a#x2308;log2na#x2309; storage cells and the computational costs of our solution are less than a#x00BD;n log2n hash function evaluations.

A multi-input single-output (MISO) controller using model predictive control is proposed for improving stability and fuel economy at idle speed for the Belt-Starter Generator (BSG) Mild Hybrid. Unlike the conventional algorithm which uses the electronic throttle control (ETC) and spark advance as actuators, ETC and torque of BSG are simultaneously employed as control inputs for maximum authority to maintain idle speed at desired value. The recursive least square technique is employed to identify the engine as a first-order MISO linear model. A nonlinear engine model established in Matlab/Simulink is used to evaluate the proposed and conventional algorithms. The proposed algorithm is also implemented on a V2 engine. Simulation results show that the proposed algorithm has less speed deviation than the conventional one under the presence of torque disturbances and model uncertainties. Since the spark timing can be kept at optimal condition, the fuel consumption of proposed algorithm is smaller than that of the conventional one.

The methods to construct the Hilbert-Peano curve are recursive and non-recursive, methods of L-grammar system, different methods have different characteristics. In this document, from the prospective of non-recursive to analyze the characteristics of Hilbert-Peano curve, adopt the amplification curve characteristic matrix iteration algorithm constructs the Hilbert-Peano curve, compares the algorithm with the non-recursive algorithm in time-space-consuming. Prove that this algorithm has more advantages on large scale than L - system of non-recursive algorithm.

In view of the envelope migration problem occurs when high speed missile borne chirp radar detects low-speed moving target, in the paper, the method of applying the missile borne inertial navigation information and envelope interpolation displacement method to compensate envelope movement is proposed to improve the accumulation performance of missile borne chirp radar. Then, the influence of missile borne chirp radar envelope movement to accumulation and the principle of envelope interpolation displacement compensation algorithm are analyzed. Finally, the simulation results show the effectiveness of the method.

The range-Doppler map (R-D map) of ship target echo can be obtained from coherent radar. Due to the difference between scatters of ship targets and the radar line of sight angle, the ship target in the R-D map generally need to cross several Doppler unit, and in general the maximum point of the signal in the R-D map will not be the tracking point, to reduce the effects of amplitude fluctuations and angular glint needs the proper use of the R-D map. In this paper, the performances of area weighted method and unbiased geometrical center method for the targets of amplitude fluctuations and angular glint are compared. Experiment shows that unbiased geometrical center method is superior to the area weighted method for the targets of fluctuations and angular glint.