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Noise impact is the most sounds are subjective evaluation, hearing, and can significantly affect human health and wellbeing. The effects of noise on the human body include hearing loss, impaired growth and development, overall tension, and sleep disturbance in children and adolescents, and decreased ability to the building environment safety. Although it is difficult to classify the specific effects of noise, noise affectless is also considered by many ecologists to be destroying or eliminating, and pollution plays an important role. FPGA (field-programmable gate array) is used to measure and estimate the instantaneous amplitude of environmental noise and uses advanced architecture for picking up noise-polluted audio signals. A high-performance algorithm refers to the number of arithmetic operations (multiplication, division, and addition) noise value are calculate the output value of a system. Memory Requirements Specifies the amount of memory needed to store system parameters, past input, output past, and any intermediate calculated values. The effect of limited accuracy means that the quantitative effect is inherent in the implementation of any digital system. High-performance algorithm technique for cancel the noise in the desired signal. Environmental noise must be correlated with the noise component of the audio signal in order to be positively correlated and effectively removed.

Night-time excessive luminance Outdoor LED display screens (OLDSs) are widely used in urban areas, which yield potential safety hazards to vehicle traffic at night. In this study, we evaluated the effects that coloured light projected from excessive luminance OLDS has on vehicle driving safety along urban roads at night. Based on road lighting environmental characteristics at night and using reaction time (RT) testing software under different white field luminance (WFL) conditions, the RTs for small targets (STs) with different colours of OLDS were examined. First, in combination with field tests, excessive luminance values of typical OLDSs at night (1,000, 3,000, and 5100 cd/m2) were determined; then, experimental simulation scenes were established by integrating real photos with software simulations. Next, the RT experiments were conducted, followed by obtaining the influences that different colours have on the RTs and visual missing dots (MDs) under different WFL conditions. The results showed that, in addition to blue light, the coloured light of OLDSs can improve a driver's ability to recognise small targets and reduce RTs in the case of low WFL values, but the coloured light causes more MDs and affects traffic safety. The findings also indicated that the night recognition abilities of females under the influence of projected OLDS coloured light was better than that of males.

Plate-like Zn2W barium hexagonal ferrites were prepared using a combined coprecipitation and molten salt method. The thermal decomposition behavior of precipitates was systematically studied by TG–DSC and XRD. Pure plate-like Zn2W barium hexagonal ferrites with optimal properties were obtained at a synthesis temperature of 1150 °C for 1 h. Phase composition, morphology and magnetic properties of the Zn2W ferrite powders synthesized at different temperatures (1100–1250 °C) and different holding times (0.5–3 h) were investigated by XRD, SEM and VSM. The electromagnetic parameters were studied by VNA. Saturation magnetization of Zn2W ferrite synthesized at 1150 °C for 1 h reached the maximum of 76.24 emu/g, whereas coercivity decreased with the increase in synthesis temperature and holding time.

In this paper we investigate the optimal risk control and dividend distribution problem for a diffusion model with a terminal value. Usually the insurer cedes risk by means of a reinsurance contract, and pays dividends out dynamically from the surplus. Consider that the insurer is trying to balance risk control and dividend payout in terms of reinsurance and dividend distribution policies. Then the objective is set to make a dynamic choice of reinsurance policy and dividend distribution policy, which maximizes the sum of the expected discounted dividends up to ruin time and the expected discounted terminal value. There are two novelties in this paper. Firstly, we formulate the optimal control problem in terms of general reinsurance control policies. Each of the proportional reinsurance, the excess-of-loss reinsurance and combination of the two can be treated as a special case. It is shown that, under an expected premium principle, the dynamic excess-of-loss reinsurance is of optimal type within the general reinsurance contracts. Secondly, considering the excess-of-loss reinsurance policy and terminal value, we obtain the explicit expressions for the value function and optimal control policies by solving the HJB equation method. At the end of this paper numerical calculations are done to illustrate the influence of the terminal value on the value function and optimal policies as well.

Previous work demonstrated that a multi-objective evolutionary algorithm could be successfully employed as an optimiser to make the design of flat-walled multi-layered anechoic linings more efficient. In the present work, such an algorithm is employed to investigate the practical aspects of the application of multi-layered polyurethane foams as the flat-walled anechoic lining. The investigation includes aspects such as the efficacy of a single layer of material, the minimum number of layers of linings to achieve the minimum overall thickness for low (100 Hz), mid (250 Hz) and high (500 Hz) cut-off frequencies, the use of the three-layered lining composite for low to mid cut-off frequencies and the effect of air gaps.

Previous investigations indicated that a flat-walled, multi-layered anechoic lining system, with an overall thickness slightly less than a quarter of a wavelength, could be used to achieve a required cut-off frequency. However, the work proved to be tedious and time consuming because of the numerous trial-and-error measurements involved. On the other hand, the successful application of a method of calculating the overall acoustic impedance of multi-layered absorbing systems has indicated that the design of multi-layered absorbing systems can be carried out on a desktop computer. In the present work, a MATLAB genetic and evolutionary algorithm toolbox is implemented as the optimiser to aid and speed up the design process. The optimisation results indicate that a three-layered lining system can achieve results comparable with quality wedge-type anechoic linings with overall thickness slightly less than a sixth of a wavelength at the 100 Hz cut-off frequency.

Computational intelligence (CI) techniques offer powerful alternatives for investigating acoustical issues and providing acoustical solutions to problems. This paper presents information on two CI techniques by applying them to the sound transmission performance prediction and design of floor–ceiling constructions. First a simple neural network (NN) model for predicting the airborne sound transmission of typical floor–ceiling constructions is presented and explained in detail. This model is accessible to researchers with knowledge of neural network analysis (NNA) for further sophistication, specialisation or hybridisation. The model may also be used by architects and others with no knowledge of NNA and no access to any specialised neural network software. Evolutionary algorithms (EAs) were then applied to search the multidimensional space created by the neural network model in order to optimise the airborne sound transmission of floor–ceiling constructions within the range of design parameters utilised in buildings.

This article uses the Over-lapping Generation model to study individuals' optimal decision on consumption, insurance, investment, and education expenses. We first discuss the individuals' demand for insurance considering intergenerational transfer payments and education expenses. We show that survival insurance is more like an investment closely related to risky assets and human capital, while life insurance serves more as an indemnity; the optimal education expenses ratio is independent of individuals' risk aversion coefficient, and the ratio of optimal investment expenditures only relies on social risk attitudes, the characteristics of risky assets, and the price of survival insurance.