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This paper studies electromagnetic parameters' impact of λ/4 type dielectric absorber on absorbing properties. Calculation shows that the maximum absorption amount is corresponding to specific values of K and R when absorber's permittivity is stable, when the thickness of material is determined and the real part permittivity is increased, the absorption peaks move to lower frequency and reduce the distance between adjacent peaks, while the imaginary part of permittivity and resistance of membrane resistance only affect absorption peaks' amount but have no effect on the peaks' position. Accordingly, it is reasonable to adjust the material's electromagnetic parameters according to the above rule when the high-performance λ/4 dielectric-type absorber is prepared.

This paper studies the effect on absorbing property of content and length of the carbon fibers of λ/4 type absorber made of carbon fiber membrane and gypsum board. The experimental results show that absorbing property of λ/4 type absorber made of carbon fiber membrane and gypsum board firstly increases and then decreases with the increase of the content or length of the carbon fibers. The absorbing property is best while carbon fiber membrane’s length is 2mm and content is 2.8% composited with gypsum board whose thickness is 1.5cm. The maximum absorption is-27.08dB.

According to the principle of electromagnetic wave absorption, functionally reforming thermal insulating materials for building, through designing and theoretically simulating of the λ/4 model, using carbon fiber film, the article has successfully prepared insulation coatings for X-band electromagnetic wave absorption. Result shows, with the thickness of 3.0 mm in 8 ~ 12 GHz band, 100% of bandwidth below-10 dB can be reached. New materials can be used such as the surface of the thermal insulation of buildings and X-band electromagnetic interference protection.

Electromagnetic radiation affects normal operation of electronic devices and causes harm to human health, the use of electromagnetic radiation protective material, especially the electromagnetic wave absorption material, is an effective method for interference control and radiation protection, λ / 4 type dielectric absorber with a simple and practical nature, the protective layer should be added to ensure its durability in practice, this article discusses the gypsum board as the substrate, the thickness of conventional protective layer's material impacts on the absorbing properties. Studies show that: the position of absorption peak moves to lower frequency with increase of the protective layer's thickness by the theory and experiment, this paper puts forward the protective layer's thickness criterion's impact on the absorption characteristics, the thickness less than 0.05 cm has little effect on absorption characteristics in S band , which can simplify theoretical calculation and be convenient to select a material; when the thickness of the protective layer has a significant effect on absorption, the relationship among the parameters of absorber can be found according to theoretical simulation, thereby reducing or eliminating the impact of protective layer thickness on absorption characteristics.

According to the principle of electromagnetic wave absorption, functionally reforming thermal insulating materials for building, through designing and theoretically simulating of the λ/4 model, the article has successfully prepared EPS composite gypsum boards for electromagnetic wave absorption. The result shows that, a maximum absorption of-18.7dB at 3GHz and 85% of bandwidth below-10dB was achieved under following conditions: using 380Ω/□ resistive film, specimen thickness of 1.50cm. However, by using phase modulation membrane (PMM),it achieved a maximum absorption of-20dB and 100% of bandwidth below-10dB. This new composite materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.

large thickness of λ/4 type absorber has been an important issue, which affects its application and urges to address. In this paper, λ/4 Type absorber made of carbon fiber membrane, instead of resistive film, and Gypsum board. Its designed for thinning and we took Simulation analysis and experimental testing for it. Results show that, while carbon fiber membrane with a length of 2mm and content of 2.8%, λ/4 type gypsum composite absorber has better absorbing in S-band. Compared with the resistive film, absorber achieved thinning of 10.6%.

The problem of WLAN anti -interference has become an important issue that affects the application. This paper explores the electromagnetic parameters' optimization of λ/ 4 type dielectric absorber in 2.4GHz and 3.6GHz .Studies show that: through the early design of the material's parameters, such as complex permittivity and thickness, the obtained ideal electromagnetic parameters' area can achieve a predetermined reflectivity at the desired frequency , then choose material to get high absorbing preparation , which can provide design basis for the preparation of different frequency band and high performance electromagnetic wave absorber.

Support vector machine (SVM) is a statistical learning theory based on a structural risk minimization principle that minimizes both error and weight terms. A SVM model is presented to predict compressive strength of concrete at 28 days in this paper. A total of 20 data sets were used to train, whereas the remaining 10 data sets were used to test the created model. Radial basis function based on support vector machines was used to model the compressive strength and results were compared with a generalized regression neural network approach. The results of this study showed that the SVM approach has the potential to be a practical tool for predicting compressive strength of concrete at 28 days.

Based on the principle of electromagnetic wave absorption, through the double-layer matching design and simulation analysis, taking foam cement panel as the dielectric material, combining with the resistive film, the paper has successfully prepared high-performance and broad-band foam cement absorbing panel for electromagnetic pollution control. The result shows, with the use of double-matching design that combines 140 Ω/□ resistive film with foam cement absorbing panel whose each layer thickness is 1.4 cm, in the S band , 100% of bandwidth below-10 dB and 95% of bandwidth below-14 dB can be reached, a maximum absorption of-19.6 dB at 2.45 GHz, the width of the absorption is far more than that of λ/4 type absorber. New materials can be used for the improvement of indoor electromagnetic environment and pollution control.

This paper reported a new type MDF absorber of high absorption and Broadband was successfully prepared, according to the Electromagnetic Wave Absorbing Theory, by means of the theoretical design and simulation analysis by using MDF as the dielectric material and And with the resistance film composite. Results shown that the resistance of resistive film was 195Ω/□, the monolayer combined sample with thickness as 1.4cm in 2~4 GHz frequency bands, the range of absorbing over -20dB could achieve 50%, and all absorption could exceed -15dB in the whole S-band, the maximum absorption peak was -25dB, moreover, the absorption bandwidth of MDF was more than λ/4 Type EWM-absorber. The new materials could be used to improve residential electromagnetic environment and control pollution.

This paper reports that according to the principle of EMW-absorption, thermal insulating EMW-absorber for building was designed and theoretically simulated of the λ/4 type. The EMW-absorption properties of composites in the band of 2-4 GHz were examined, A maximum absorption of-20 dB at 3 GHz and 80% of bandwidth below-10 dB was achieved under following conditions: using 380Ω/□ resistive film, specimen thickness of 2 cm. Similarly, absorbing materials for 2.45 GHz have successfully designed and prepared,a maximum absorption of-17 dB at 2.45 GHz, and 65% of bandwidth below-10 dB can be reached. New materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.

Soft clay can be found in many places around the country of China. Along with the rapid economic development in coastal areas, civil engineers could meet many soft soils. These settlements appear quickly and may continue for a long period of time due to the consolidation behavior. This paper investigates the deformation characteristics of soft clay foundation from trial dates. Support Vector Machine model is proposed to predict settlement of soft clay. The settlement forecasting show Support Vector Machine method has advantages in its simple structure excellent capability in studying and good application prospects. The results of this study proves the elasto-viscoplastic model rationality based on laboratory test and have shown the SVM approach has the potential to be a practical tool for predicting settlement of soft clay foundation.

In this paper, a new leakage measurement method based on the temperature field and temperature gradient field is proposed for detecting the leakage location and measuring the leakage rate in damaged seal material. First, a heat transfer leakage model is established, which can calculate the leakage rate based on the temperature gradient field near the damaged zone. Second, a finite element model of an infinite plate with a damaged zone is built to calculate the leakage rate, which fits the simulated leakage rate well. Finally, specimens in a tubular rubber seal with different damage shapes are used to conduct the leakage experiment, validating the correctness of this new measurement principle for the leakage rate and the leakage position. The results indicate the feasibility of the leakage measurement method for damaged seal material based on the temperature gradient field from infrared thermography.

The prediction strength of cement is an important task in civil engineering. In this study, the support vector machine (SVM), a novel type of learning algorithm based on statistical theory, has been used to predict the 28d strength of cement. The seven input variables used for the SVM model for prediction of strength are content of slag, SO3 content, cement fineness, 1d compressive strength and folding strength, 3d compressive strength and folding strength. Comparison between SVM and artificial Neural network (ANN) methods is also presented. The study shows that the SVM methods can achieve better accuracy and generalization than the ANN methods; and SVM has the potential to be a useful and practical tool for prediction strength of cement.