Signal recognition and hearing protectors with normal and impaired hearing.

Recognition of acoustic signals when perception is subject to interference from noise has already been extensively studied. In this study the influence of hearing protectors (HP) (plugs, muffs) and hearing loss on signal recognition is examined. Different spectrums and levels of the noise are also included. The test results are shown as the masked threshold for the signals heard and identified. In the case of normally hearing subjects a frequency-independent HP (plug) improves hearing performance, while frequency-dependent HP (muffs) tends to worsen it, especially with low-frequency noise. Hearing losses even worsen hearing performance when plugs are worn. Design suggestions are made to optimise signal recognition. Minimum signal-to-noise ratio and the use of HP are discussed.     

Energy and environment scenarios for Senegal

In this paper, the energy and environmental dimensions of several proposed energy strategies for Senegal are explored. An analytical framework to compare the energy and measurable environmental impacts of a set of scenarios is developed, and the limitations of the quantitative approach are discussed. It is found that policies to promote substitution of liquid petroleum gas (LPG) for charcoal use in households may actually reduce greenhouse gas emissions, while also improving more important near-term environmental problems. Substitution of LPG for charcoal would not necessarily lead to a significant increase in Senegal's oil import bill, since other petroleum product usage will continue to dominate. Despite past industrial sector initiatives, considerable potential for energy efficiency investment remains, and presents additional opportunities for minimizing environmental impacts.     

LEAP2000:可持续能源分析的工具

LEAP是由斯德哥尔摩环境研究所(SEI)波士顿中心领导的一项合作项目,旨在为一体化的能源环境分析建立一套新的分析软件和数据库.LEAP2000项目的产品应尽早获得以广为传播.