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In order to make the peak and offset of the signal meet the requirements of artificial equipment, dynamical analysis and geometric control of laser system has become indispensable. In this paper, a locally active memristor with non-volatile memory is introduced into a complex-valued Lorenz laser system. By using numerical measures, complex dynamical behaviors of the memristive laser system are uncovered. It appears the alternating appearance of quasi-periodic and chaotic oscillations. The mechanism of transformation from a quasi-periodic pattern to a chaotic pattern is revealed from the perspective of Hamilton energy. Interestingly, initial-values-oriented extreme multi-stability patterns are found, where the coexisting attractors have the same Lyapunov exponents. In addition, the introduction of a memristor greatly improves the complexity of the laser system. Moreover, to control the amplitude and offset of the chaotic signal, two kinds of geometric control methods including amplitude control and rotation control are designed. The results show that these two geometric control methods have revised the size and position of the chaotic signal without changing the chaotic dynamics. Finally, a digital hardware device is developed and the experiment outputs agree fairly well with those of the numerical simulations.

The Shenzhen innovation light source facility (SILF) is a fourth generation of medium energy synchrotron radiation light source, which focuses on supporting the development of the domestic core industries, basic science frontier research and major strategic requirement, such as integrated circuits, biomedicine, advanced materials and advanced manufacturing. With the Shenzhen Municipal Government's approval of the SILF project proposal on Sep10 2020, the feasibility study of the SILF was completed in 2022, and the preliminary design of the SILF are in progress. The accelerator complex is composed of the 200 MeV linac, the 0.2–3.0 GeV booster and the 3.0 GeV storage ring. The circumference of the storage ring is 696.0 m, which includes 28 hybrid seven-bend achromat lattice periodic units to achieve the emittance below 100 pm·rad. The detailed physics design of the SILF storage ring will be presented in this paper.

This letter presents the fabrication of InP double heterojunction bipolar transistors (DHBTs) on a 3-inch flexible substrate with various thickness values of the benzocyclobutene (BCB) adhesive bonding layer, the corresponding thermal resistance of the InP DHBT on flexible substrate is also measured and calculated. InP DHBT on a flexible substrate with 100 nm BCB obtains cut-off frequency f T = 358 GHz and maximum oscillation frequency f MAX = 530 GHz. Moreover, the frequency performance of the InP DHBT on flexible substrates at different bending radii are compared. It is shown that the bending strain has little effect on the frequency characteristics (less than 8.5%), and these bending tests prove that InP DHBT has feasible flexibility.

It’s very important to make use of finite element analysis software to assist the structure design of power battery connector. In this paper, Ansys workbench was used to establish the electric-thermal coupling model of finite element simulation for the connector assembly, and the temperature field simulation calculation and analysis were carried out for the connectors of different thickness under the condition of high current. The results show that the maximum temperature of the connector increases with the decrease of its cross-section thickness, and the higher the current is, the longer the power time will be, the higher the temperature will be. In addition, the connector with thickness of 0.8 mm has the risk of fusing under the action of 500 A current.

Mullite porous ceramics with high porosity and good mechanical properties were prepared by foaming method combined with gel casting process using kaolin and alumina as main raw materials and sodium polyoxyethylene ether sulfate as foaming agent. The effects of sintering process and magnesium oxide content on the microstructure and properties of mullite porous ceramics were investigated. The studies show that: With the addition of magnesium oxide, the amount of mullite produced and the compactness of the sample will increase. At this time, the microscopic morphology of mullite is needle-like and prismatic, and the mechanical properties are better. and the pore size distribution gradually tends to be between 0.1-0.2mm and 0.2-0.3mm. The addition of magnesium oxide, The amount of mullite phase increased, the densification degree of the sample increased, and the acicular and prismatic mullite phases with good mechanical properties were mainly formed, and the porosity of mullite porous ceramics decreased and the compressive strength increased. The pore size distribution gradually tends to be between 0.1-0.2mm and 0.2-0.3mm. As the sintering temperature increases, the porosity of mullite porous ceramics decreases and the compressive strength increases. With the extension of the holding time, the amount of mullite phase generated increases, the porosity remains basically unchanged, and the compressive strength increases.

Background Hydroxycamptothecin (HCPT) is a topoisomerase I inhibitor, and it has been widely used clinically in the treatment of primary liver cancer, gastric cancer, and other tumors. The clinical application of HCPT is limited by its water solubility, and it has certain toxicity to patients with tumor. Therefore, the effective tumor site accumulation of HCPT is necessary. Methods This work studied the inhibitory effect of HCPT on the proliferation and migration of human liver cancer cells (HepG-2) and used carboxymethyl chitosan (CMC) and hyaluronic acid (HA) to modify graphene oxide (GO) as nano-carrier materials, which load HCPT to achieve a drug delivery system for liver tumors with good biocompatibility and high drug loading. Results HCPT can significantly inhibit proliferation and migration of HepG-2, enhance the release of reactive oxygen species, reduce mitochondrial membrane potential, and induce apoptosis. The GO-CMC-HA/HCPT drug delivery system enables HepG-2 to uptake more HCPT, thereby inhibiting its proliferation and improving the efficacy of HCPT in vivo and in vitro. Conclusion This study explored a potential therapy strategy by preparing a GO-based tumor-targeted drug delivery system.

Taking the dry coal shed of a coal-fired power plant as an example, the reticulated shell structure model of large-span three-centered cylindrical is established according to the specification requirements, and its design and optimization are carried out. It is to use the full stress design method to establish multiple comparison models by adjusting the thickness of the grid, to do the analysis and calculation for obtaining the comparison results of steel consumption, maximum vertical displacement and overall stability of different models, and then to determine the optimal span ratio of the large-span reticulated shell structure. All of these aim to draw relevant conclusions and provide reference for the design and optimization of similar large-span three-centered cylindrical reticulated shell engineering.

Methane (CH4) gas sensors play an important role in industrial safety and detection of indoor gas quality. In general, metal oxide semiconductor sensing materials with nano-structure have high responses to the target gas. However, the sensor resistance is usually very high. Considering the practical application, it is vital to reduce base resistance and improve sensitivity for gas sensors. Herein, Pd-doped SnO2 nanoparticles were prepared as the basis material by a simple sol-gel method. In order to adjust the resistance, the pentavalent metal element (Sb) was introduced via a simple doping route. As CH4 sensing layers, the prepared SnO2-sensors doped with Pd and Sb exhibited the most obvious resistance reduction effect. Meantime, excellent sensing performances including high response, fast response/recovery time, excellent reproducibility and great stability were also obtained. In-depth research has shown that the ability to reduce resistance depends on the effective internal doping of cation with high valence. The enhanced sensing capability can be attributed to the "synergistic effects" including catalytic effects of novel metals, increased oxygen vacancies and decreased band gap energy. This work can provide a new opportunity to design metal oxide sensing materials with low resistance and high sensitivity.

This paper explores the two-way risk spillover effect between fin-tech innovation and the real economy, applying the time-varying Copula-CoVaR method and quantitatively analyzing the two-way risk spillover effect and risk spillover asymmetry. The research results show that the yield sequence of fin-tech innovation and real economy is asymmetric when risk impact, the impact of bad news is stronger than good news, and there is dynamic linkage effect and positive correlation between fin-tech innovation and the real economy. In addition, there are significant two-way risk spillover effects, namely, risk events in one market can cause increased risk in the other market, but this pair of risk spillover effect is not completely symmetrical.

A multilayered filler made up of Cu foam and Ag-28Cu foils was used to successfully braze (TiB+Y2O3)/titanium matrix composites (TMC) and silicon nitride ceramics (Si3N4). The microstructure of the TMC/Si3N4 joints obtained at different brazing parameters was investigated. The results showed the interfacial structure of the joints is composed of TiCu, TiCu2, Ag (s, s), Cu (s, s), TiN and Ti5Si3 phases. The growth equation of the TiN layer was established and its thickness was increased with respect to the brazing time and brazing temperature. Optimal shear strength of approximately 180 MPa was achieved when the joint was brazed for 10 min.

We propose an efficient scheme to control Goos–Hänchen (GH) shifts of the reflected and transmitted beams in a cavity containing Er3 + -doped yttrium-aluminum-garnet (YAG) crystal with a four-level Er3 + ionic system. It is found that both the values and signs of the reflected and transmitted GH shifts can be coherently controlled by tuning the relevant optical parameters, such as the incoherent pumping rate, and the intensity and detuning of the driving field. Furthermore, we propose a scheme for such a configuration of the reflected GH shift as a family of reflection-type optical switchings. It is shown that the average port spacing and reflectivity of the optical switching can reach approximately 1.03 mm and 16.88, respectively, which indicate the high performance of switching function. Our proposal may provide a possibility to implement optically tuned optical switching.

According to the needs of risk assessment, path planning and emergency rescue of hazardous chemicals transportation, a risk assessment and decision support system of hazardous chemicals transportation was designed, including system structure, implementation process and main functions. The feasibility analysis of key technologies was carried out. This system took Geographic Information System (GIS) as the support platform, and integrated multi-source information such as hazardous chemicals, global positioning system (GPS), geographic environment, Meteorological information, etc. Based on classical pollution diffusion models and relevant domestic and foreign standards, the index system of transportation risk assessment was built. Then the quantitative index of risk assessment and the early warning sign could be given, and the hazard area of the chemical accident was determined. At last, this risk assessment and decision support system provided suggestions on route optimization for hazardous chemicals transport, which could be severed as scientific basis for emergency rescue and command decision.

This letter reports on the first demonstration of wafer scale flexible InP double heterogeneous bipolar transistors (DHBTs) with record cut-off frequency (f T) and maximum oscillation frequency (f MAX). The as-fabricated DHBTs on 3-inch InP bulk substrate are separated by epitaxial layer lift-off, followed by adhesive bonding onto flexible substrate. Radio frequency measurements reveal that the InP DHBTs on flexible substrate exhibit a f T of 337 GHz and f MAX of 485 GHz, representing the highest f T and f MAX ever reported in flexible electronics. Moreover, InP DHBTs on flexible substrate have good consistency and the functional transistor yield is more than 73%. The results provide ways to accelerate the time for flexible electronics toward future applications working at multi-gigahertz range.

The indoor healing landscape has a positive influence on people’s mind and physical health, indicated from the studies. This research aims to discuss the residents’ emotional problems during the home quarantine under the context of COVID-19 and put forward the strategies to construct a residential indoor healing landscape system based on disaster psychology, which is conducive to relieve residents’ emotional problems. Firstly, the general introduction includes the adverse effects on residents’ minds and physical health from major public health emergencies and the function of indoor healing landscape; secondly, the questionnaires are used to discover the residents’ emotional problems during the epidemic; finally, the strategies to construct the residential indoor healing landscapes are put forward to therefore regulate residents’ mind and physical health during home quarantine and working and living at home after the epidemic.

One of the most important goals for companies that provide cloud computing services is to maintain high availability on large computer systems. In order to accomplish such objective, it is necessary to discovery the reason of poor availability. Software aging is a main factor in cloud computing services, leading to software failures, poor performances and may result in system downtime. This paper investigates the software aging effects on the OpenStack cloud computing platform and describes a forecasting model based on Hidden Markov Models. The prediction analysis of the Hidden Markov Models on the key performance data of the system shows that the Hidden Markov Models has excellent predictive performance and is suitable for the prediction of the reliability of the cloud server system.

Coal water slurry boiler has attracted great attention in the field of urban heat system because of its efficient and clean coal combustion. The coal water slurry contains 35% moisture, which makes the waste heat recovery potential of flue gas greater. After the combustion of coal water slurry, the 100°Cunsaturated flue gas becomes 50°C saturated wet flue gas after Wet Desulfurization Process. The Direct Contact Thermal Storage System and Heat Pump technology are used to realize the deep recovery of low-temperature flue gas. The technology has been successfully applied in the 6×70MW coal water slurry boiler of La Shan Heat Source Company. After 120 days of operation, 393000 GJ of flue gas waste heat is recovered, about 23000 tons of coal water slurry is replaced, and 84000 tons of flue gas condensate is recovered. It has good economic and social utility. It is an effective way to recover and utilize waste heat from flue gas of coal-fired boiler, and has a broad application prospect.

In the recent decade, people’s interest for forests has increased tremendously throughout the globe. So, providing good forest landscape space to visitors has become an important issue for the landscape designers. Because, good forest resource planning and development can not only drive the sustainable development of the forest industry, but also its ripple effect can induce improvement in agricultural industry and economy in the region. The present study identified the evaluative behaviors among visitors walking on the trails of Akasawa national recreational forest, the birthplace of forest bathing in Japan. The study determined the factors that influenced the satisfaction rates of the visitors. The significance of this study is not only to improve the planning and design of the forest space itself, but also to provide theoretical guidance for the planning of the regional landscape of the rural areas attached to it. The study results revealed, visitors’ subjects for evaluation changed with the surrounding environment. While visitors appreciated large-scale landscape elements, such as “large-size trees” and “buttress roots” within coniferous forests. They valued small-scale landscape elements such as “flowering plants” within broad-leaved or mixed forests. Another important issue came out as a result of the present study is that the light and dark changes in the forest walking trail can continuously awaken the evaluation behavior of tourists. In this study visitors displayed evaluative behaviors most frequently on the Mukaiyama Course. It is rich in different types of forest stands and has variance illumination levels. Factors that influence the satisfaction rates of visitors were “landscape”, “vegetation”, “trail condition” and “ease of walking”. Factors that influence the frequency of evaluative behaviors included “landscapes” surrounding the trails and “ease of walking”. Through this study we can see that when we need to plan the forest spatial walking trails, it is very necessary to consider small-scale landscape elements, rich in different types of forest stands with varying illumination levels.

In order to verify whether the coating can meet the stringent requirements of the ship’s long sailing cycle, harsh environment, and various unfavorable factors such as fire conditions, physical and mechanical performance tests, endurance tests, and Micro and micro tests of the three coating samples were carried out. The hardness of the ZS2000, ZS hybrid and ZS1000 coatings measured by the experiment were ⩾8H, ⩾7H, ⩾3H, respectively; the thermal conductivity values of the three coatings are very low, respectively 0.074 W/(m·K), 0.034 W/(m·K) and 0.025 W/(m·K), which can meet the requirements of the engine in unexpected flame environment; the original adhesion of the coating is the best, but the adhesion of the coating is reduced after the damp heat cycle and the salt corrosion at room temperature, and the salt spray resistance, damp and heat resistance of the coating are good, and no obvious defect is observed; TG experiments have found that the remaining percentages of the three coatings ZS1000, ZS2000, and ZS hybrid are 85.29%, 80.72% and 77.90% respectively. The thermal stability of ZS1000 is the best, and the three coatings have the best remaining balance. The difference is not large, so they all have good thermal stability. Analyzing the results of a series of performance tests, it is found that the comprehensive performance of the ZS hybrid coating is better than that of the ZS2000 and ZS1000 coatings.

The pure MoS2-carbon composites (MoS2-C) and Fe modified MoS2-carbon composites (Fe/MoS2-C) were successfully synthesized through a facile two-step hydrothermal method by adding soft template of CTAB and applied as piezocatalysts to degrade Rhodamine B. The as-obtained catalysts were characterized by the X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicated the hybrids have large surface area, mesoporous structure, more edges and unsaturated S atoms. By comparing the muffle furnace samples (open air calcination) with the tube furnace one (closed Ar calcination), Fe/MoS2-C catalysts with tube furnace show the higher degradation activities (12.8% versus 5.8%). The possible degradation mechanisms are also discussed.

Active thermal management is essential for the operation of modern technologies like electronic circuits and spacecraft systems to deal with the complex control and conversion of thermal energy. One basic requirement for the materials is its tunable and reversible thermal properties. Here, we try to provide a systematic investigation of the thermal smart materials composed of low-dimensional solid particles suspended in liquid media, whose structures and properties can be tuned by external field. A two-step theoretical model, which takes into account the effects from particle aggregation and orientational variation, was proposed and obtained reasonable agreement with both literature and our own experimental results. Graphene nanosheets/Mg-Al layered double hydroxides (GNS/LDH) were fabricated and their silicone oil suspension shows reversible thermal conductivity switching under DC electric field due to the formation/break-up of chain-like structures with a maximum switching ratio around 1.35×. This study reveals the underlying mechanism of thermal conductivity enhancement in nanoparticle suspensions, and provides a preliminary example to design and fabricate responsive thermal materials for the next generation technologies.

With the development of information technology, microservices have been applied to more and more industries. Firstly, we introduce microservices and microservices architecture, analyse the main problem of civil affairs informatization, and explain the composition of microservices architecture. Secondly, we give the key technology of microservices which include abstract methods of microservices, microservices process management and the schedule of microservices workflow. Finally, we talk about the situation of civil affairs applications for using microservices architecture and give the conclusion.

LED lights are widely used in highways and tunnels because of their long life, low light attenuation in recent years. The influence of color rendering (CRI) on lighting safety has attracted people's attention as the increase in demand. In this paper, the influence of different CRI on perception luminance of human eyes under different fog transmittance and different luminance was calculated and analyzed. A calculation model of human eye perception luminance considering mesopic vision and fog concentration was proposed. An experiment was conducted by observing different colored targets in a fog chamber. The results showed that yellow targets and high CRI can provide higher perception luminance and the latter is recommended for tunnel lighting in interior zone.

In view of the low efficiency and fallibility of the feature-based matching algorithm in object detection, a new algorithm based on convex hull region and generalized hough transform is proposed.By using the region of interest to narrow the detection region and applying the key feature points to the voting elements of the generalized hough transform, the computation is greatly reduced.Firstly, the fused key feature points are extracted and filtered to generate the convex hull region which is combined with the GBR clustering algorithm to determine the region of interest. Secondly, the key feature points are taken as the voting elements in the generalized hough transform algorithm to obtain the final result. In this paper, dozens of various transformation experiments(scaling, rotation, noise, etc.) based on the proposed algorithm are compared with other similar methods, and it is verified that the method has higher efficiency and accuracy according to the theoretical basis and concrete implementation, which can meet the real-time and high-precision requirements in industrial detection.

Targeting at the problems of response lag and poor control effect of traditional PID speed control system for brushless DC motor, a novel PID speed regulation system based on fuzzy optimization was proposed in this paper. On the basis of analyzing basic working principle of brushless DC motor, the new fuzzy selftuning PID optimal controller is introduced, the controller output switches power MOSFET devices by changing the duty ratio of PWM control signal, thus the speed control of brushless DC motor was realized. Both the fuzzy optimized PID control introduced in this paper and the traditional PID control are respectively simulated and compared under the Matlab/Simulink environment. The results show that with the fuzzy optimized PID control system has better performance than traditional PID control.

The aquatic environmental regulations at home and abroad is rarely considered from the perspective of water body and water bank treatments together and coordinated economic and cultural development. To improve the environmental quality of waterfront cities and activate and revitalize their vitality in waterfront areas, it is necessary to make full use of the water system and its surrounding green space, to get through the waterfront slow-moving system, and connect various natural and human elements along the waterline. Li Xi, the Secretary of Guangdong Province, China, proposed the concept of “Bi Dao”. “Bi Dao” is a comprehensive regulation concept that integrates natural elements and economic and social attributes with water as the main focus. “Bi Dao” is constantly evolving, innovating and enriching in practice and provides a useful tool for exploration and practice in China’s environmental regulation efforts. “Bi Dao” will improve the quality of cities on both sides of the river or lake and lead to industry transformations and upgrades, which will promote economic and social development and improve the level of ecological civilization.

Urban river pollution is one of the most prominent environmental problems in Chinese cities that have been trying to prevent and control. The aim of this paper is to propose an urban river governance framework from the perspective of systematic governance. The point source pollution control is the premise of river regulation. Increased impervious surface in urban areas due to urbanization continuously increases the concentration of stormwater runoff pollutants. Many low-impact development facilities such as sunken lawn and rain gardens can also effectively reduce with non-point source pollution. Controlling the pollution source eliminates some pollutants in the river though it does not improve its own ecosystem. Since the self-purification ability of an unstable ecosystem is weak, the restoration of ecosystems is critical component of the water environment management. Urban river regulation should focus on sustainable management of river sources to meet the human needs, while ensuring the health and continuous development of river ecosystems, water ecology, water landscape and water culture.

Water saving irrigation as an effective measure to improve the utilization rate of water resources and alleviate water deficit has been widely practiced in arid and semi-arid regions. In this study, an integrated drip irrigation and subsurface pipe drainage system was developed to study the total nitrogen emission concentration of sunflowers during the whole growth period. The test and results show that total nitrogen concentration of farmland drainage in the spring irrigation period exceeded the standard V of “Surface Water Quality Standard”. In addition, prolonging the leaching time or reducing the irrigation quota can effectively reduce the concentration of total nitrogen in farmland drainage.

We quantify and correct systematic errors in PPMXL proper motions using extragalactic sources from the first two LAMOST data releases and the Veron-Cetty & Veron Catalog of Quasars. Although the majority of the sources are from the Veron catalog, LAMOST makes important contributions in regions that are not well-sampled by previous catalogs, particularly at low Galactic latitudes and in the south Galactic cap. We show that quasars in PPMXL have measureable and significant proper motions, which reflect the systematic zero-point offsets present in the catalog. We confirm the global proper motion shifts seen by Wu, Ma, & Zhou (2011), and additionally find smaller-scale fluctuations of the QSO-derived corrections to an absolute frame. We average the proper motions of 158,106 extragalactic objects in bins of 3x3 degrees and present a table of proper motion corrections., Accepted for publication in RAA; 12 pages, 6 figures (Fig. 1 at reduced resolution); full table of corrections available in online journal, with arxiv ancillary files (as ASCII table), or by request

Curve fitting has a wide range of applications in engineering design, computer graphics, etc. In some case traditional least square methods can’ t use known conditions as fully as possible, so we introduce a notion named baseline. We firstly estimate a baseline and use the point to line distance as the parameter of the probability density as the weight value of the least square. The software we developed shows that our methods needs less running time and can makes better fitting consequence.

Extracting text information from raw images has always been a hot and difficult problem in computer vision research. Due to blurred image, uneven illumination and complex backgrounds, etc., the recognition of natural scene digit is difficult to achieve desired results. In this paper, an encoder-decoder neural network model is proposed to solve the problem of recognition of indefinite length digit sequences in natural scene. The encoder is convolutional neural network (CNN), and the decoder is long short-term memory (LSTM). The encoder accepts a fixed-format image and outputs a fixed-length feature vector; the decoder accepts the feature vector and outputs a predictive sequence of indefinite length. The verification based on Google Street View house number Dataset (SVHN) shows that our method has a good performance. After 10 hours of training, whose accuracy is 96.57%.

This article will start from how to calculate the volume of Steinmetz Solid by double integration, and expand to formation, cross section and unfolding of it by Matlab in a brand new way, in order to explore the internal structure and application. Further, we expand to polygonal Steinmetz Solid by Matlab to acquire more comprehensive understanding and mastery of it.

Water, energy and food are three important resources for human to face serious security risks. A systematic perspective, namely Water, Energy and Food Nexus (WEFN), was proposed to achieve the sustainable human development. In this study, a method of hierarchical weight assignment based on synergetic theory and Shannon information theory was applied in the Bayan Nur city, China. Through calculating order degree of order parameter components of resources, society, economic and environmental dimensions, the order degree of order parameters and sub-systems and the order entropy were obtained. It is found that water resources supply, energy supply, energy consumption and food price would dominate the corresponding trends in water, energy and food sub-systems respectively. The water and food sub-system may play a more dominant role in the harmonious assessment of WEFN system in the study area. Although the variance of the order degree of sub-systems and the order entropy were small, the WEFN system was still moving toward an unstable state, which could aggravate the inharmonious degree of WEFN system in the study area.

A method of car face image segmentation based on haar-like features and improved cascade classifier was proposed to solve the problems of insufficient classification recognition performance and too long training time of the current classifier. First, the haar-like features of the image are calculated based on integral graph. Then the extracted feature values are input into the cascade classifier for training. Finally, the trained classifier was used to detect the vehicle face and segment the image of the vehicle face. In this paper an adaptive threshold setting method is proposed. The experimental results show that the method has the better performance than the traditional methods, and has better application prospects.

Since there are few researches on multi-channel surface electromyography (EMG) devices, this paper presents a new design scheme. The system uses highly integrated chips and designs a new wearable electrode array. Also, the data is transmitted by wireless WiFi with a high bandwidth. Scalable modular architecture is also applied to make the system suitable for different scenarios. Through experimental tests, the device can work for more than 5 hours, effectively collecting the EMG signals generated when the hand muscles move.

With the development of wireless communication technology, WiFi-based indoor personnel positioning has received more and more attention. The channel state information (CSI) extracted from the commercial network card can be used to determine the position status of the indoor personnel. In this paper, we propose a method based on WiFi personnel to determine the presence and intrusion of indoor personnel by real-time positioning of personnel. The method uses principal component analysis to preproces the data, extracts the main features in the amplitude information, and uses the support vector machine (SVM) to realize the training and classification of indoor position samples, and uses the obtained indoor position status information to determine the regional invasion situation and the specific location of the personnel. Experiments show that this method can effectively judge the intrusion of people in specific areas of the city and achieve precise positioning under the condition of low resource consumption.