Papers by Keyword: Detection

Abstract: Finite-resolution digital receiver is considered to be a potential solution to meet the severe demand of ADC that results from wideband of IR-UWB signal. However, the quantized distortion is totally different from full-resolution quantized signal. In this paper, the finite-resolution quantized signal model is derived. Based on the correlation receiver, estimation and detection performance of finite-resolution and full-resolution digital receiver are analyzed in the paper. The analytical results agree with the numerical results exactly and the template estimation performance using midtread quantizer is better than that using the adjacent midrise quantizer.

Abstract: The detection algorithm CFAR is very mature in SAR image process field and the efficiency is very good. In the paper, CFAR is tried to be used in sonar image process. In order to solve the problem that the target part leaking to the background, a new method target detection of sonar image based on bis-parameter with adaptive windows is proposed. The size of adaptive windows can be adjusted to totally cover different targets. The experimental result showed that the complex multi target can be detected by the proposed method in a high accuracy.

Abstract: High pressure jet grouting piles have a wide range of application in the engineering field. However, nowadays the increasing construction depth leads to an increasing difficulty of construction,which involves that the quality of construction is much more difficult to control. In this paper, some examples are given of the Luoyuan ultra-deep high pressure jet grouting piles. These examples are described with the used construction quality control methods and preventive recommendations for work construction quality detection methods. That is why this paper has an important guiding significance for similar projects.

Abstract: In recent years, natural disasters occurred more frequently in our country, dangerous housing in rural areas often cause a lot of casualties and property losses. Due to the shortage of national financial, the government decided to focus financial support on the renovation of dilapidated buildings. In order to have a deep understand of the rural structure, distribution law and the proportion of the dilapidated housing, after the survey of the housing situation in Dongying County Dongying City, Jiaxiang County Jining City and Yiyuan County Zibo City, this article made the statistics and analysis of the status of housing in these three counties. The result of analysis and statistics show that the rural housing mainly conclude adobe housing, brick masonry housing and block masonry housing, the proportion of dilapidated houses in rural housing is about 10.9%, the dilapidated buildings are mainly distributed in the mountain, because the mountain areas foundation of economic is weak, and the housing structure is mainly in the form of adobe housing and stone masonry housing. The main types of dilapidated housing are adobe housing and stone masonry housing primarily, the brick masonry housing newly built is in relatively low risk level. The government finances should inclined to transform the dilapidated housing in the mountain area first. In order to improve the quality of new housing in rural areas, this new housing in rural areas will also need to pay attention to the problem made some conclusions.

Abstract: Water distribution system is one of the most critical facilities in cities, and is more fragile compared with other structures. Losses in a water distribution system are often existed before health monitoring is implemented. This paper proposes to detect an existing local loss in a water distribution system on the basis of optimal monitoring of water pressure. The local loss is assumed at different positions with different extents, and pressures at monitoring stations is calculated, and the loss is then detected by minimizing the difference between the calculated and monitoring pressures at the monitoring stations. The efficiency is validated by example analysis. It is shown that an existing local loss is more reliably detected in a water distribution system with optimal monitoring.

Abstract: The existence of underground goaf causes serious harm to the security and stability of the surface installations. Using the ground penetrating radar (GPR) detects the nine road in Jinzhou District of Dalian across the railway line three goaf grouting reinforcement. This article introduces the principles and technical methods of GPR, including data acquisition and data processing of GPR, discussing the effect of using GPR technology to detect the superficial goaf.

Abstract: The low strain method has the advantages of simple, fast detection is widely used in the pile testing. The low strain method was presented to pile test on a communication hinge engineering of China Mobile Group Gansu Co.,Ltd. The basic theory, tesing method of pile and judgment standard about the ultrasonic wave method are analyzed.

Abstract: In order to explore detecting function for grouted density and empty hole ofcorrugated pipe, the paper proposes a method. Firstly, detect groutedcorrugated pipes and concrete (avoiding corrugated pipes) using elastic wave,judge defective corrugated pipes through comparative analysis of the data.Secondly, detect the defective corrugated pipes using ultrasonic wave, analysisthe test data, determine the specific location and size of defect in corrugatedpipes. Finally, verify by actual design. The result shows that judged locationand size of the empty hole are consistent with the actual situation. So it isfeasible to detect grouted density and empty hole of prestressed corrugatedpipe with the method. So as to provide theoretical guidance for grouteddetection of corrugated pipe.

Abstract: In this paper, the measurement conditions of heavy metal enriched on the filter membrane using X-ray fluorescence were talked about. According to the heavy metal enriched on the film, the specific parameters were analysed. Through many experiments, the suitable parameters were decided. In order to excite mainly heavy metal in air, the excitation voltage should be not less than 30kV. The excitation current should be between 20μA and 60μA. The measured distance should be between 4mm and 15mm. The best choice of pulse shaping time is around 6.4μs. These parameters setting should have very good application value in air heavy metal measurement.

Abstract: In order to detect whether there are nucleic acid components interested in the testing samples, this study manuscript presents a method and a process based on MEMS technology and biosensor technology. Although MEMS micro cantilever is very sensitive for stress mass, we must aggravate the cantilever for the reason of microscopic DNA mass is very weak. In order to achieve the purpose of their molecules detection level, gold nanoparticles (GNPs) which are combined with hybridization information is taken to aggravate MEMS cantilever, and we employ Au - S chemical bond of GNPs and dithiol HS(CH₂)₆SH to combine and fix DNA probe, and then employ target DNA which is marked with biotin to combine GNPs by Biotin - Streptavidin combining. We use the method of layer by layer to amplify the signal again until meet the hypersensitized requirements. Last we apply multi-channel microfluidic technology to achieve high-throughput detection.