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Two studies were conducted to examine distance classes of vegetation (foreground, middleground and background) and scene composition (presence of vegetation in left, center or right section of the image) as predictors of perceived scenic beauty. In study one, 41 students rated 63 landscape scenes with regard to scenic beauty. The Scenic Beauty Estimation Method was used to derive interval scale beauty values (SBEs). For each landscape image, areal measures of vegetation in each distance class and for each vertical section were taken and used as predictors. Presence of haze, clouds and human impacts were also recorded. Among the most important contributors to scenic beauty were amount of center middleground vegetation, and center background vegetation. Left foreground vegetation and right foreground vegetation were found to have significant and opposing regression weight signs—negative for the left and positive for the right. Study two was conducted to determine whether these opposing regression weight signs for foreground vegetation were due to a perceptual right-left bias or to some specific content in the image itself. In the second study, the photographic slides used to present landscape scenes to subjects were reversed so that the content which was previously on the right was now left, and vice versa. Thirty-nine students rated the reversed slides with regard to their scenic beauty. The signs of the regression weights in study two shifted such that left foreground was now positively valued and right foreground was negatively valued. This finding suggests that viewers are sensitive to foreground content and its placement in the image, and not simply to one side of the field of vision.  相似文献   
23.
This article discusses the development of corporate social responsibility (CSR) in Brazil from the perspective of the Ethos Institute of Business and Social Responsibility. The Institute is a not‐for‐profit, non‐governmental organization, that has played a leading role in the Brazilian CSR effort. In Brazil, CSR initiatives have a long tradition of philanthropy, a consequence of the country's great social inequalities. The increased attention to corporate social responsibility has paralleled growing concern about sustainable development and the intensifying activities of pressure groups (consumers, customers, investors, NGOs, labour unions, the media, among others) that have been increasing since the 1990s as natural resources are progressively becoming exhausted, social tensions rising and environmental conditions deteriorating worldwide. This article identifies problems and obstacles to the growth of corporate social responsibility in Brazil, as well as advances and alternatives for CSR and towards creating conditions for the country to be internationally competitive and sustainable in the financial, social and environmental areas.  相似文献   
24.
Since 1968, research in public transportation planning has included an increasing number of analyses of the perceptions and attitudes of people who use and live in proximity to the systems (Nash and Hille 1968, McMillan et al. 1969, Wachs 1976). The results of the study reported here suggest that race and gender may explain more about attitudes toward the community impact of a transit system than do the levels of user satisfaction with the system. The implication for future research in this area is that surveys employing “satisfaction” and “importance” as indicators may not be using appropriate indices of evaluation. This study reports the results of a 1980 attitude survey of the perceptions of black and white men and women living within a two-block corridor along the Metropolitan Atlanta Rapid Transit Authority (MARTA) east line in Atlanta, Georgia. The research supports the Atlanta Regional Commission (ARC) Transit Impact Monitoring Program (TIMP). The survey used a stratified random sample technique to identify 100 households in which in-home interviews were subsequently conducted. A further stratified sampling procedure designated the gender and age of persons to be interviewed. The analysis included the isolation of responses by gender and race and used the chi-square statistic at the 0.05 significance level. The results identity differences in responses of males and females, blacks and whites.  相似文献   
25.
Vertical profiles of isoprene and monoterpenes were measured by a proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) at heights of 3, 15, 32, 64, and 102 m above the ground on the Institute of Atmospheric Physics (IAP) tower in central Beijing during the winter of 2016 and the summer of 2017. Isoprene mixing ratios were larger in summer due to much stronger local emissions whereas monoterpenes were lower in summer due largely to their consumption by much higher levels of ozone. Isoprene mixing ratios were the highest at the 32 m in summer (1.64 ± 0.66 ppbV) and at 15 m in winter (1.41 ± 0.64 ppbV) with decreasing concentrations to the ground and to the 102 m, indicating emission from the tree canopy of the surrounding parks. Monoterpene mixing ratios were the highest at the 3 m height in both the winter (0.71 ± 0.42 ppbV) and summer (0.16 ± 0.10 ppbV) with a gradual decreasing trend to 102 m, indicting an emission from near the ground level. The lowest isoprene and monoterpene mixing ratios all occurred at 102 m, which were 0.71 ± 0.42 ppbV (winter) and 1.35 ± 0.51 ppbV (summer) for isoprene, and 0.42 ± 0.22 ppbV (winter) and 0.07 ± 0.06 ppbV (summer) for monoterpenes. Isoprene in the summer and monoterpenes in the winter, as observed at the five heights, showed significant mutual correlations. In the winter monoterpenes were positively correlated with combustion tracers CO and acetonitrile at 3 m, suggesting possible anthropogenic sources.  相似文献   
26.
The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and carcinogenicity. In the present work, a new adsorbent, δ-MnO2 modified activated carbon, was prepared, and its performance for the uptake of arsenate and arsenite species from aqueous solutions was investigated by batch experiments. Various techniques, including FESEM-EDX, p-XRD, XPS and BET surface area analysis, were employed to characterize the properties of the adsorbent and the arsenic adsorption mechanisms. The results showed that δ-MnO2 covered on the surface and padded in the pores of the activated carbon. Adsorption kinetic studies revealed that approximately 90.1% and 76.8% of As(III) and As(V), respectively, were removed by the adsorbent in the first 9 hr, and adsorption achieved equilibrium within 48 hr. The maximum adsorption capacities of As(V) and As(III) at pH 4.0 calculated from Langmuir adsorption isotherms were 13.30 and 12.56 mg/g, respectively. The effect of pH on As(V) and As(III) removal was similar, and the removal efficiency significantly reduced with the increase of solution pH. Arsenite oxidation and adsorption kinetics showed that the As(V) concentration in solution due to As(III) oxidation and reductive dissolution of MnO2 increased rapidly during the first 12 min, and then gradually decreased. Based on the XPS analysis, nearly 93.3% of As(III) had been oxidized to As(V) on the adsorbent surface and around 38.9% of Mn(IV) had been reduced to Mn(II) after As(III) adsorption. This approach provides a possible method for the purification of arsenic-contaminated groundwater.  相似文献   
27.
In a recent article (Tilton, Humphreys, and Radetzki, 2011), Tilton et al. argue that even when investor stocks are declining an increase in investor demand can cause a commodity's price to rise. They contend that this conclusion, which is based on two hypothetical examples, is both contrary to conventional wisdom and counter-intuitive. In my comment on the article (Olle Östensson, 2011), I challenged this finding. In a reply to my article, Tilton et al. maintain that their original finding is valid: investor demand can be driving commodity prices higher even when stocks are falling. In my present reply, I contend that their argument with respect to the first example confuses the actions of a minority of investors with those of all investors and is well accommodated within the framework of traditional theory. I further argue that their second example rests on an assumption regarding investor behavior that is unproven and that in any case falls outside the framework of analysis of futures markets.  相似文献   
28.
In a recent article (Tilton et al., 2011), we argue that even when investor stocks are declining an increase in investor demand can cause a commodity's price to rise, a conclusion that is both contrary to conventional wisdom and counter-intuitive. In his comment on our article, Olle Östensson (2011) challenges this finding. After assessing his concerns in this reply, we maintain that our original finding is valid: investor demand can be driving commodity prices higher even when investor stocks are falling.  相似文献   
29.
孙明燕  宋波  张荣 《环境技术》2010,28(1):13-14,21
国家标准GB/T18287-2000《蜂窝电话用锂离子电池总规范》中明确规定了锂离子电池的20℃常温,高温,恒定湿热性能,震动,碰撞,自由跌落等环境试验的具体方法及环境试验后的放电性能测试方法。  相似文献   
30.
大剧院观众厅是音乐家最后的乐器,音乐效果是由观众厅声学反应出来的。前面演奏者要把声音传播给观众席,再从观众席后排反声回给演奏者,这样的互动是最完美的剧院设计。  相似文献   
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