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1.
Exposure-effect relationships between the level of road traffic noise at the most exposed side of a dwelling's façade and the residents' reactions to road traffic noise have been estimated. The relationships are based on five Norwegian socio-acoustic studies featuring 18 study areas from two cities and a total of near 4000 respondents. The survey questionnaires distinguish between noise annoyance experienced right outside the apartment and when indoors. Exposure-effect relationships for all degrees of annoyance are estimated simultaneously from ordinal logit models. These predict road traffic noise annoyance when right outside the apartment and when indoors, respectively, as a function of the road traffic noise level outside the most exposed façade. Separate analyses indicate that Norwegians react stronger to road traffic noise than results from a recent compilation of socio-acoustic surveys would lead one to believe. People having inferior single glazing windows report higher indoor annoyance.  相似文献   

2.
This article describes the roadside traffic noise surveys conducted in heavily built-up urban areas in Hong Kong. Noise measurements were carried out along 18 major roads in 1999. The measurement data included L10, L50, L90, Leq, Lmax, the number of light vehicles, the number of heavy vehicles, the total traffic flow, and the average speed of vehicles. Statistical analysis using the analysis of variance (ANOVA) and Tukey test (p<0.05) reveals that the total traffic flow and the number of heavy vehicles are the most significant factors of urban traffic noise. Multiple regression was used to derive a set of empirical formulas for predicting L10 noise level due to road traffic. The accuracy of these empirical formulas is quantified and compared to that of another widely used prediction model in Hong Kong--the Calculation of Road Traffic Noise. The applicability of the selected multiple regression model is validated by the noise measurements performed in the winter of 2000.  相似文献   

3.
4.
This study concerns road traffic noise in Greater Cairo, the capital and the largest city in Egypt and the eleventh biggest city in the world. Extensive measurements were carried out in 21 sites in Greater Cairo. Restrictions were introduced to improve environmental conditions including: (i) a ban on horns, (ii) a ban on horns and trucks, (iii) a ban on horns, trucks and noisy buses. Equivalent noise levels (LAeq) were measured before and after these restrictions. The equivalent noise level was considerably reduced by the bans. This shows that the town planner can use various strategies to change the traffic composition in order to achieve quieter city environments. The degree of annoyance was measured by means of questionnaire. The results showed that there was a strong relationship between road traffic noise levels and the percentage of highly annoyed respondents.  相似文献   

5.
Environmental noise can produce negative effects on people’s health since it interferes with basic activities such as sleeping, resting, studying and communicating. These effects depend not only on the physical characteristics of the noise itself, but also on parameters associated to each person and each environment. It is thus important to study noise pollution from a quantitative point of view as well as a from the point of view of the annoyance that it produces in the population.We have conducted a social survey aiming to identify the main sound sources, evaluate the annoyance and analyse the main effects of noise on people. The survey was distributed to a sample of people living approximately in the corners of an imaginary 250 m grid placed over the map of the city of Valladolid (Spain). The same corners were used to perform in situ measurements for a noise city map.There are two main purposes for this research work: (1) we want to compare the objective noise measurements to the annoyance reported by the people in order to find some kind of dose-effect relationship, and (2) we want to analyse how the population of Valladolid evaluates noise reduction from an economical and social point of view.  相似文献   

6.
Annoyance expressed in a railway noise survey is compared with that in two road traffic and three aircraft surveys in order to determine whether responses to various environmental noises are similar or are source-specific. Railway noise is less annoying than other noises at any given high noise level. Railway noise annoyance increases less rapidly with increasing noise level. At high noise levels this gap in reactions averages about 10 dB but ranges from 4 dB to more than 20 dB. Comparisons between the findings in the different surveys can be made only after considering differences in noise index calculation procedures, human response measurement procedures and annoyance moderating conditions. The methodology for comparing surveys is examined. It is found that methodological uncertainties lead to imprecise comparisons and that different annoyance scales give different estimates of intersurvey differences.  相似文献   

7.
This study aims to form a functional film on the glass substrates by plasma polymerization of glycidoxypropyltrimethoxysilane (γ-GPS). Low frequency plasma generator was used to prepare plasma polymer thin films of γ-GPS (PlzP-γ-GPS) on glass substrates at different plasma powers (30, 60 and 90 W) and exposure times (5, 15 and 30 min). XPS analyses were utilized to reveal the presence of functional groups in plasma polymer films. When higher plasma powers are applied, relative amount of Si-C bonds decreases and the amount of Si-O bonds increases. Contact angle measurements were performed to evaluate surface characteristics. Atomic force microscopy (AFM) studies were carried out to elucidate morphological changes. From AFM observations, it was obtained that the surface roughness slightly increased with the increase of plasma power from 30 to 90 W.  相似文献   

8.
In the present relationship between Barkhausen noise and domain structure evolution along the hysteresis loop in 3% Si–Fe has been investigated. The noise power spectrum has been measured vs. induction during cyclic magnetization of the material at a very low constant rate. The obtained results show that the behavior of the noise power along the magnetization curve can be related to the character of the domain structure rearrangements taking place at different levels of induction. Such a connection is reflected in a relationship between the noise power and the shape of the hysteresis loop. The measured noise power spectra are interpreted through the use of a suitable model. This makes possible to connect the shape of the magnetization curve to the microscopic parameters characterizing the dynamic of the domain wall during a large Barkhausen jump.  相似文献   

9.
The temperature dependence of spin-lattice relaxation rates was analyzed for four high-spin nonheme iron proteins between 5 and 20 K, for three high-spin iron porphyrins between 5 and 118 K, and for four high-spin heme proteins between 5 and 150 to 298 K. For the nonheme proteins the zero-field splittings, D, are less than 0.7 cm(-1), and the relaxation is dominated by the Orbach and Raman processes. For the iron porphyrins and heme proteins D is between 4 and 12 cm(-1) and the relaxation is dominated by the Orbach process between about 5 and 100 K and by a local mode at higher temperatures. The relaxation rates for the heme proteins in glassy matrices extrapolated to values at room temperature that are similar to values obtained by NMR relaxivity in fluid solution. This similarity suggests that for high-spin Fe(III) heme proteins with effective intramolecular spin-lattice relaxation processes, the additional motional freedom gained when a relatively large protein goes from glassy solid to liquid solution at room temperature has little impact on spin-lattice relaxation.  相似文献   

10.
The aggregate formation of trans‐2,3‐dimethylcyclopropyllithium ( 2 ) was studied in diethylether (DEE). With the help of the isotopic fingerprint method three clusters, a monomer, a dimer, and a fluxional tetramer in the ratio 1.00:0.53:0.22 were identified at 187 K. In the presence of 1 equivalent of LiBr cyclopropyllithium ( 1 ) forms in DEE at 163 K a mixed dimer and a mixed tetramer, while in THF a mixed dimer dominates. Under the same conditions 2 and 2,2,3,3‐tetramethylcyclopropyllithium ( 3 ) form in the solvent mixture DEE/THF (1:1) mixed dimers, as does 2 also in THF.  相似文献   

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