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It is critical for the safety monitoring of highway bridges that beam bridge damage can be identified from the dynamic response of passing vehicles. Numerical simulations of passing vehicles were conducted utilizing the vehicle–bridge coupling vibration theory and the indirect measurement method. Fast Fourier transform was performed on the time history response of vehicle acceleration, and the driving frequency component response and its instantaneous amplitude square value (IAS value) were obtained by band-pass filtering and Hilbert transform processing. The identified IAS value detected the damage location of the bridge. The identification method of IAS value is used to analyze the applicability of a simply supported beam bridge, a continuous beam bridge, and an irregular skew beam bridge. The effects of vehicle speed, vehicle damping, bridge damping, and a social vehicle on damage identification are discussed. The results show that the effect of damage location is better when the vehicle speed is less than 4 m/s. In the presence of social vehicles, the excitation on the bridge increases, and the damage location can still be accurately determined by the IAS method. Vehicle damping and bridge damping have little effect on the results of damage identification. In structural health monitoring for bridges, this paper can provide a theoretical reference for the application of IAS motion sensing to identify the damage location indirectly.

In high-frequency (HF) hybrid sky-surface wave radar, the first-order sea clutter broadening is very severely under the influence of ionosphere, which affects the detection of ship target. A cascaded method is described to correct HF signals reflected by the ionosphere and backscattered by the sea surface for ionospheric frequency modulation, which produces spectral line smearing. Firstly, the radar configuration, sea clutter broadening model are introduced based on the newly-developed integrated HF sky-surface wave experimental system. Then, a new ionospheric decontamination method based on General Parameterized Time-frequency (GPTF) analysis is proposed to correct the ionospheric phase contamination with large amplitude. Finally, the proposed method is examined by measured data. Experimental results indicate that the proposed method can well suppress the broadening sea clutter and improve the ship target detection performance.

A novel linear microprobe array (LMPA) has been developed by a conventional microfabrication method from silicon. The LMPA leverages the properties of conventional microwire with additional features of naturally formed regular spacing. With the help of periodic microprobe arrays and double-side V-grooves fabricated in advance between each pair of the two microprobes’ rear ends, the number of microprobe units for assembly in one array can be flexibly chosen by cleavage fracture from the LMPA. The fabrication method was demonstrated and the prototype device was assessed by electrochemical impedance spectroscopy (EIS) and in vivo test. The SNR of the spikes recorded was 6.

A new optical wireless sensing system to detect the acoustic emission (AE) signals generated from the monitoring structure was presented in this paper. In the sensing system, an relocatable AE sensor head based on fiber Bragg grating (FBG) was developed. Also a wireless module was connected with the designed FBG AE sensor head in a compact package. The results of the pencil lead breaking experiment indicated that the wireless FBG AE sensing system has excellent output response correspond very well to the traditional PZT AE sensor. The frequency responses of the designed system were also investigated. It has demonstrated that the system has shown a good performance in discriminating AE waves with different resonant frequencies.

The trade of wastes in the world has been increasing and China has become the largest importer of wastes. This paper examines the import trend of different wastes and finds out that the total import volume to China approved by the Chinese government keeps increasing and the illegal trade can not be banned despite repeated prohibitions; therefore, China is not only “a world factory”, but actually “a global garbage dump”. In order to well understand the implications of wastes import, this paper further analyzes the resource and environmental effects and risks of different wastes imports as well as the strong driving force of wastes imports. Based on these detailed analysis and solid data, policy recommendations are put forward to reduce the demand for raw materials, to further strengthen the inspection of and supervision over the international trade of the wastes that can be used as raw materials by using the life cycle analysis and risk analysis, to improve the environmental standards and strength...

Assume that two reinsurers participate in a reinsurance treaty, and both the insurer and two reinsurers adopt the variance premium principle. Based on the above jump risk model, we use the diffusion approximation risk process to model the assets of insurance company with reinsurance. To avoid bankruptcy, the insurance company will receive capital injections, we assume that each capital injection is not less than a certain constant d>0, and it also will incur some fixed transaction costs and proportional taxes, i.e., impulse injections with constraint. For the diffusion model, we study the minimum of the expected discounted nonlinear capital injection, using Hamilton-Jacobi-Bellman (HJB) method, and we give explicit solutions for the value function and the optimal control strategy. Finally, for the influence of parameters on the optimal results, we also give numerical analysis.

Objective: To understand the current situation of China's health food, and to provide a reference for the development of Healthcare Industry. Methods: Create a database of China's health food information from China Food and Drug Administration website. Conduct a systemic analysis of the regional distribution, annual distribution, dosage forms distribution and functions of health food. Results: Guangdong and Beijing have produced the most health food; the data line of health food quantity has two peaks in 1997 and 2004. From 2013, the number of health food started growing steadily; health food formulations are mainly capsules and tablets; the functions of health food are centered mainly on strengthening the immune system and relieving physical fatigue. Conclusion: Innovation is needed in the formulations and the functions of domestic health food; China’s domestic health food industry should increase investment in science and technology; Overall, China’s health food industry has a bright future.

The increasing use of cellular phones in our society has brought focus on the potential detrimental effects to human health by microwave radiation. The aim of our study was to evaluate the intensity of oxidative stress and the level of neurotransmitters in the brains of fetal rats chronically exposed to cellular phones. The experiment was performed on pregnant rats exposed to different intensities of microwave radiation from cellular phones. Thirty-two pregnant rats were randomly divided into four groups: CG, GL, GM, and GH. CG accepted no microwave radiation, GL group radiated 10 min each time, GM group radiated 30 min, and GH group radiated 60 min. The 3 experimental groups were radiated 3 times a day from the first pregnant day for consecutively 20 days, and on the 21st day, the fetal rats were taken and then the contents of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), noradrenaline (NE), dopamine (DA), and 5-hydroxyindole acetic acid (5-HT) in the brain were assayed. Compared with CG, there were significant differences (P