Search

With China's urbanization, the construction industry has generated massive construction and demolition waste (C&DW), leading to severe environmental pollution and social problems. However, the currently proposed policies have not promoted the sustainable development of the C&DW recycling market. This paper constructs a tripartite evolutionary game model of construction production enterprises, construction enterprises, and the government. The decision-making evolution laws of relevant stakeholders at different stages of the development of the C&DW recycling market are identified through equilibrium stability analysis. The results show that in the initial stage, the government can help encourage enterprises to participate in C&DW recycling through appropriate subsidy and penalty measures. As the recycling market matures, enterprises achieve profits through market mechanisms and the proportion of enterprises participating in recycling increases. At this time, the government no longer plays a leading role, and the strategy evolves into non-supervision. In addition, the government should design carbon emission reduction policies for carbon quota and trading according to the market status to exert positive effects. Hence, this study provides a theoretical basis for the governments of developing countries to effectively manage C&DW market development. [ABSTRACT FROM AUTHOR]

The aftershock activity of Wenchuan Ms8.0 earthquake showed different spatial and temporal distributions along two different segments of the Longmenshan fault. This difference was likely the result of segmentation of the earthquake rupture process, which in turn may be the result of the fault’s segmentation in its long-term geotectonic condition.

Objective: Single-channel noise reduction (SCNR) and dynamic range compression (DRC) are important elements in hearing aids. Only relatively few studies have addressed interaction effects and typically used real hearing aids with limited knowledge about the integrated algorithms. Here the potential benefit of different combinations and integration of SCNR and DRC was systematically assessed. Design: Ten different systems combining SCNR and DRC were implemented, including five serial arrangements, a parallel and two multiplicative approaches. In an instrumental evaluation, signal-to-noise ratio (SNR) improvement and spectral contrast enhancement (SCE) were assessed. Quality ratings at 0 and +6 dB SNR, and speech reception thresholds (SRTs) in noise were measured using stationary and babble noise. Study sample: Thirteen young normal-hearing (NH) listeners and 12 hearing-impaired (HI) listeners participated. Results: In line with an increased segmental SNR and spectral contrast compared to a serial concatenation, the parallel approach significantly reduced the perceived noise annoyance for both subject groups. The proposed multiplicative approaches could partly counteract increased speech distortions introduced by DRC and achieved the best overall quality for the HI listeners. Conclusions: For high SNRs well above the individual SRT, the specific combination of SCNR and DRC is perceptually relevant and the integrative approaches were preferred. [ABSTRACT FROM AUTHOR]

CHENFIT-AMP is a novel nonlinear strategy that combines the fitting (gain prescription) and amplification (gain implementation) procedures for cochlear hearing loss. The fitting part of CHENFIT-AMP prescribes gain for outer hair cell (OHC) and inner hair cell (IHC) loss, respectively. The gain for OHC loss varies with the cochlear gain decided by the value of OHC loss and the input level. The gain for IHC loss varies with the value of IHC loss only and will be limited to a constant if there is a “dead region.” The amplification part of CHENFIT-AMP is responsible for estimating the input level and cochlear gain based on Chen's loudness model. CHENFIT-AMP is evaluated with four typical audiograms and nine individual audiograms. A widely used nonlinear fitting procedure, NAL-NL2, is evaluated to compare prescription results with CHENFIT-AMP; a standard nonlinear amplification algorithm, multichannel compression (MCC), with the parameters provided by NAL-NL2, is also evaluated to compare amplification results with CHENFIT-AMP. For long-term average speech spectrum (LTASS) inputs, CHENFIT-AMP generally prescribes similar gain as NAL-NL2 for the typical audiograms; however, gain prescribed by CHENFIT-AMP is more individualized than NAL-NL2 for the individual audiograms, especially when the audiograms have big deviations in the slope. For LTASS-shaped noise input, the gain implemented by MCC with parameters provided by NAL-NL2 cannot completely realize the gain prescribed by NAL-NL2. For speech sentence inputs, average ratings by subjects indicated that amplification by CHENFIT-AMP was preferred and led to a louder perception than that by MCC with parameters from NAL-NL2. [ABSTRACT FROM PUBLISHER]

The source rupture process of the M7.0 Lushan earthquake was here evaluated using 40 long-period P waveforms with even azimuth coverage of stations. Results reveal that the rupture process of the Lushan M7.0 event to be simpler than that of the Wenchuan earthquake and also showed significant differences between the two rupture processes. The whole rupture process lasted 36 s and most of the moment was released within the first 13 s. The total released moment is 1.9×10N m with M=6.8. Rupture propagated upwards and bilaterally to both sides from the initial point, resulting in a large slip region of 40 km×30 km, with the maximum slip of 1.8 m, located above the initial point. No surface displacement was estimated around the epicenter, but displacement was observed about 20 km NE and SW directions of the epicenter. Both showed slips of less than 40 cm. The rupture suddenly stopped at 20 km NE of the initial point. This was consistent with the aftershock activity. This phenomenon indicates the existence of significant variation of the medium or tectonic structure, which may prevent the propagation of the rupture and aftershock activity. The earthquake risk of the left segment of Qianshan fault is worthy of attention. [ABSTRACT FROM AUTHOR]

High-resolution three-dimensional V and V/ V images in the Longtan reservoir area were obtained from local earthquake data by using 3,178 events with total 24,153 P-wave and 23,987 S-wave arrivals collected from 23 seismic stations. The tomographic images show that significant V heterogeneities can be seen at layers of different depth in the Longtan reservoir area. Low- V anomalies both beneath and around the main rivers in the reservoir area may be related to the composition of rocks which are mainly deposit carbonate and arenaceous shale, which contributes to water saturation. We deduced that the high porosity rocks beneath the main rivers may be fully saturated with water. The phenomenon that V is relatively high in the area which is 10-20 km away from the rivers indicates that horizontal saturation of water is limited within a small range of area that is about 10-20 km from the main rivers. The characteristic is significant that seismicity in the Longtan reservoir area is coincident with the distribution of the low- V area. V/ V tomographic images show that V/ V ranges from 1.8 to 2.05 in shallow layers above 4 km depth beneath the Longtan reservoir, suggesting the properties of the rocks are limestone and shale. At the depth of 7 km, the distribution of V/ V image varies quite remarkably, especially in the dam area. This demonstrates that the range of influence by the saturation of water in the media below the reservoir surface can reach 4-7 km depth in the dam area. [ABSTRACT FROM AUTHOR]