Comparison of public perception and risk management decisions of aircraft noise near Taoyuan and Kaohsiung International Airports

This study uses multiple linear regression to identify factors contributing to perceived risk among residents near Taoyuan and Kaohsiung International Airports, the effect of perceived risk on their willingness to reduce risk, and consumption preferences that can reduce risk. Results indicated that residents' risk perception near Taoyuan Airport is lower than that near Kaohsiung Airport. Noise pollution experience, perceived probability of environmental contamination and negative effects, and perceived severity of catastrophic consequences significantly increase residents' perceived risks. Residents are willing to recognize and participate in mitigating the risks of aircraft noise pollution. The more risk residents perceive, the more willing they are to participate in disaster reduction and investigate means of improving the risk environment.     

Determining the integrated volatility via limit order books with multiple records

The integrated volatility plays an important role in risk management and portfolio selection, the estimation methods regarding the quantity have been widely investigated, either under low-frequency data or high-frequency data, or a combination of both. In this paper, we propose a measure for the integrated volatility via limit order book data with possible presence of multiple records. The estimator is valid under mild conditions and it is easily implemented. The finite sample performance of the proposed estimator has been verified by simulation studies and we apply the method to some real high-frequency data-sets as well.     

Assessment of land use compatibility and noise pollution at Imam Khomeini International Airport

This study aimed to investigate land use planning around airports, by employing Remote Sensing (RS) and Geographic Information Systems (GIS), in conjunction with an optimization algorithm using an Integrated Noise Model (INM) software, to establish the potential effects of aircraft noise at Imam Khomeini International Airport (IKIA) in Tehran. We also checked for land use compatibility with the noise levels around IKIA and the residents' reaction to the noise. The research was carried out in three stages: a) the establishment of Strategic Noise Map (SNM) scenarios of the airport operation in the years 2011, 2020 and 2030 using the INM software; b) the assessment of the results with emphasis on the study area land uses and application of RS and GIS and the exposure of residents at different levels of environmental noise; and c) the assessment of the intensity of aircraft noise annoyance at various times of day and night. The results indicated that developing IKIA together with the residential development will increase airport noise. Hence proper management and control of noise at IKIA is essential.     

Probabilistic assessment of fleet-level noise impacts of projected technology improvements

Demand projections for civil aviation have forecast increases in operations in future decades. Increases in demand are beneficial to the growth and advancement of the aviation industry, but also come with the threat of significant increase in environmental impacts. In response, the industry is focusing on programs to develop technologies for reductions in fuel burn, NO_x emissions, and noise. While aircraft-level impacts are an obvious metric of success, it is difficult to make informed robust technology investment decisions with respect to noise without understanding the fleet-level impacts. Fleet-level predictions of noise for technology explorations are especially complicated because it is computationally expensive, highly combinatorial, and airport-specific. Recently, rapid automated airport noise models have been developed, which can be simulated using Design of Experiments (DOE). The results of these simulations are used to generate surrogate models for airport noise contour area, which can be summed to yield a fleet-level impact. These models make use of simplifying assumptions to provide estimates of airport-level noise that are substantially cheaper to compute. They can be used to perform parametric trade-off analyses in conjunction with the equivalency assumption. Equivalency asserts that environmental impacts of a technology infused aircraft can be represented by scaled operations of the baseline aircraft in the same class. This simple assumption allows for the modeling of technology and market penetration factors under the same units: operations. This research uses surrogate models in conjunction with the equivalency assumption to examine two potential technology scenarios in a target forecast year, simulating technology and market performance factors to identify vehicle classes that could have the greatest impact in reducing contour area. Results show that technology and market performance of future notional Small Single Aisle and Large Single Aisle vehicle aircraft have the highest positive correlations with potential reductions in contour area.     

用于通信系统的干扰对消电路设计与实现

针对通信设备应用的复杂化和对在复杂电磁环境下工作的设备电磁兼容性提出的更高要求，通过分析对消技术的基本原理，提出了一种模拟电路和数字电路相结合的干扰对消技术，并研制出了基于该技术的干扰对消原理样机。对该样机的单机测试和系统联试结果表明，该对消技术具备点频干扰和噪声干扰的抑制能力，对消收敛时间小于100 ms，对消比大于43 dB，适合在窄带通信中应用并可推广到其他领域。该成果正逐步在实际工程中得到运用。     

小波域抑制多音干扰的扩频接收机

利用小波包理论提出了一种快速、准确地识别并且抑制多音干扰的有效方法。该方法利用小波包理论将多音干扰的各条谱线逐个定位，然后通过功率谱分析的方法来识别多音干扰的存在区间，最后将被干扰污染的区间逐个切除并反向重构接收到的信号。实验证明该方法的误比特率性能在强干扰时要优于以前的FFT域切割法。     

浅析电力网中的电磁干扰

随着科学技术的迅速发展,大量新技术新材料的应用,电力系统的容量和电压都有很大的提高,出现了盲流高压输电、晶闸管的广泛应用、电力机车、电弧炉等整流设备的发展,大量电子类家用电器的广泛使用,使电力网中谐波污染变得相当严重。二次设备的微型化、数字化、电子化增加了二次设备对暂态干扰的敏感性,使暂态干扰和高频辐射干扰问题日益突出。所以,供电网络中的电磁兼容问题必须高度重视,认真对待,否则,将对电力网造成严重后果。     

Incorporating annoyance in airport environmental policy: noise, societal response and community participation

Airport capacity continues to be one of the air transport issues that creates the most concern. The major environmental constraint for airports is the noise generated by aircraft. Annoyed communities living around airports have become a limiting factor for airport capacity and operability. This paper brings together the existing literature in the fields of airport environmental capacity, non-acoustic factors of noise annoyance, NIMBYism and environmental conflicts. We also analyze the socio-environmental conflict between Barcelona airport and the community of Gavà Mar. This case shows that the lack of trust between parties, the impossibility of predicting noise exposure, the absence of opportunities for civil society to speak and the difficulty of accessing relevant information foster annoyance and mobilization in the communities that live around the airport. In addition, it is shown that, in such a situation, communities’ reactions can evolve to a post-NIMBY stage in which proactive attitudes replace reactive ones.     

滚筒洗衣机噪声分析

本文具体针对全自动滚筒洗衣机,研究其在脱水状态下以每分钟1200转运转时所产生噪声的成因,接着提出三个改进方案,然后重新研究改进方案产生的噪声大小,以此验证改进方案的有效性。本文采用CFD软件FLUENT对所有模型进行模拟仿真分析。因为是搅拌模型,所以具体计算时采用动参考系法（MRF）进行计算。通过研究发现加强筋结构会造成涡流气流,是导致噪声问题的主要成因。在各个改进方案中,填充外围第四和第五圈栅格的方案被验证为最佳方案,既起到减噪效果又能节省填充材料。