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51.
52.
Craig H. Bullock David A. Elston Neil A. Chalmers 《Journal of environmental management》1998,52(4):335-351
Stalking (deer hunting) is an important land use and activity in the Scottish Highlands, and deer managers have traditionally maintained large numbers of female deer in order to supply a guaranteed number of stags for stalking. Unfortunately, grazing by large numbers of deer conflicts with environmental objectives that are seeking to improve upland habitats and increase the area of native Caledonian Pine forest. This study uses a multi-attribute choice experimental approach to quantify the various characteristics of the stalking experience to determine the value that amateur stalkers attach to the stag numbers, the landscape and other attibutes. Unlike previous applications of stated preference, a large proportion (one-third) of a full factorial design is used to present stalkers with different alternative stalking packages within a postal survey. The results indicate a way forward that could be agreeable to both deer managers and conservationists. 相似文献
53.
ABSTRACTContemporary smart cities have largely mirrored the sustainable development agenda by embracing an ecological modernisation approach to urban development. There is a strong focus on stimulating economic activity and environmental protection with little emphasis on social equity and the human experience. The health and well-being agenda has potential to shift the focus of smart cities to centre on social aims. Through the systematic and widespread application of technologies such as wearable health monitors, the creation of open data platforms for health parameters, and the development of virtual communication between patients and health professionals, the smart city can serve as a means to improve the lives of urban residents. In this article, we present a case study of smart health in Kashiwanoha Smart City in Japan. We explore how the pursuit of greater health and well-being has stretched smart city activities beyond technological innovation to directly impact resident lifestyles and become more socially relevant. Smart health strategies examined include a combination of experiments in monitoring and visualisation, education through information provision, and enticement for behavioural change. Findings suggest that smart cities have great potential to be designed and executed to tackle social problems and realise more sustainable, equitable and liveable cities. 相似文献
54.
This work aims to determine the maximum concentration and downwind distance at the earth's surface in two methods Briggs and standard for two conditions are slightly unstable and neutral by using the Gaussian equation at different effective heights and wind seeped at (8.9, 8.5 and 8 m/s) under lateral and vertical dispersion coefficient measurement. 相似文献
55.
Growth, yield and elements content of wheat (Triticum aestivum) grown in composted municipal solid wastes amended soil 总被引:1,自引:0,他引:1
Mamata Mishra Rajani K. Sahu Sanjat K. Sahu Rabindra N. Padhy 《Environment, Development and Sustainability》2009,11(1):115-126
A commercial formulation of composted municipal solid wastes (MSW) was used for amending soil at 0, 50, 100, 150, 200 and
250 kg ha−1 in which wheat had been grown (field experiments) and element residues of amended soil and plant parts were enumerated. MSW
amendment caused a significant improvement in soil quality. Growth (shoot length, leaf number, leaf area, tiller number, plant
dry weight and chlorophyll contents of leaves) and yield (length of panicle, number of panicles per plant and grain yield
per plant) of wheat increased gradually up to the MSW-amendment level of 200 kg ha−1. Elements, Ni, Zn, Cu, Cd, Cr, and Pb accumulated in plants from MSW amended soil, but the degree of metal accumulation was
the least in seeds in comparison to other plant parts (root, stem and leaf). Moreover, Ni, Zn, Cd and Pb, were in high concentration
in all plant parts. It is recorded that the level of 200 kg ha−1 MSW amendment caused better growth and yield of wheat, but progressive levels of metal accumulation in plant parts were recorded
due to increase in amendment levels.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
56.
有风条件下室内火灾自然排烟模型试验研究 总被引:2,自引:2,他引:0
采用缩尺度试验方法对有风条件下室内火灾自然排烟过程准稳态进行研究,分析不同补气口、排烟口位置和风向对排烟效果的影响。试验结果表明:将补气口设在迎风面,排烟口设在背风面或侧风面时将获得比没有环境风时更好的自然排烟效果;而在其他情况下,环境风将通过减小排烟口处内外压差以及对室内烟气层产生扰动来降低自然排烟效果。在设置建筑自然排烟系统时,应综合考虑火灾具体情况以及当地风速条件,选择对自然排烟有利的排烟口与补气口位置组合,以提高自然排烟的效果。 相似文献
57.
In this study, the surface chemical functional groups of Bacillus cereus biomass were identified by Fourier transform infrared (FTIR) analytical technique. It had been shown that the B. cereus cells mainly contained carboxyl, hydroxyl, phosphate, amino and amide functional groups. The potentiometric titration was conducted to explain the surface acid-base properties of aqueous B. cereus biomass. The computer program FITEQL 4.0 was used to perform the model calculations. The optimization results indicated that three sitesthree pKas model, which assumed the cell surface to have three distinct types of surface organic functional groups based on the IR analysis results, simulated the experimental results very well. Moreover, batch adsorption experiments were performed to investigate biosorption behavior of Cu(Ⅱ) and Pb(Ⅱ) ions onto the biomass. Obviously, the adsorption equilibrium data for the two ions were reasonably described by typical Langmuir isotherm. 相似文献
58.
Sardini P Robinet JC Siitari-Kauppi M Delay F Hellmuth KH 《Journal of contaminant hydrology》2007,93(1-4):21-37
An out-diffusion laboratory experiment using a non-reactive tracer was fitted using the Time Domain Diffusion (TDD) method. This rapid particle tracking method allows simulation of the heterogeneous diffusion based on pore-scale images and local values of diffusivities. The superimposed porosity and mineral 2D maps act as computation grids to condition diffusion pathways. We focused on a Palmottu granite sample, in which the connected pore space has a composite microstructure with cracks linking microporous minerals and is above the percolation threshold. Three main results were achieved: (i) When compared to the fitting obtained with one coefficient (best mean square residual R = 1.6 x 10(-2)), diffusion is shown to be suitably characterised with two coefficients related to cracks and microporous minerals (best R = 6.5 x 10(-4)), (ii) rather than imposing a local apparent diffusion coefficient D(a) independent of the local porosity Phi, a best fit is obtained by applying Archie's relationship D(a) = D(0) x G with G = Phi(m) to each pixel of the calculation grids (G is the geometry factor, D(0) is the diffusion coefficient in free fluid, and m is Archie's exponent), and (iii) the order of magnitude of the fitted diffusion coefficient or Archie's exponents (m=0 for microcracks and m=1.82 for microporous minerals) is physically realistic. 相似文献
59.
Zisheng Xing Charles P.-A. Bourque Fan-Rui Meng Roger M. Cox D. Edwin Swift Tianshan Zha Lien Chow 《Ecological modelling》2008
In this paper we present a simple hybrid gap-filling model (GFM) designed with a minimum number of parameters necessary to capture the ecological processes important for filling medium-to-large gaps in Flux data. As the model is process-based, the model has potential to be used in filling large gaps exhibiting a broad range of micro-meteorological and site conditions. The GFM performance was evaluated using “Punch hole” and extrapolation experiments based on data collected in west-central New Brunswick. These experiments indicated that the GFM is able to provide acceptable results (r2 > 0.80) when >500 data points are used in model parameterization. The GFM was shown to address daytime evolution of NEP reasonably well for a wide range of weather and site conditions. An analysis of residuals indicated that for the most part no obvious trends were evident; although a slight bias was detected in NEP with soil temperature. To explore the portability of the GFM across ecosystem types, a transcontinental validation was conducted using NEP and ancillary data from seven ecosystems along a north-south transect (i.e., temperature–moisture gradient) from northern Europe (Finland) to the Middle East (Israel). The GFM was shown to explain over 75% of the variability in NEP measured at most ecosystems, which strongly suggests that the GFM maybe successfully applied to forest ecosystems outside Canada. 相似文献
60.
Experiments on mixing and dissipation in internal solitary waves over two triangular obstacles 总被引:2,自引:1,他引:1
Chen-Yuan Chen John R.-C. Hsu Ming-Hung Cheng Cheng-Wu Chen 《Environmental Fluid Mechanics》2008,8(3):199-214
A series of laboratory experiments was undertaken in a stratified two-layer fluid to investigate the energetics of the interaction
between an internal solitary wave (ISW) and triangular obstacles, as well as to determine the partitioning of ISW energy and
its subsequent dynamics. The ISW energy was dissipated as a result of internal breaking and turbulent mixing induced by wave
instability. Tests involving different combinations of triangular obstacles in various heights and intervals and ISW of different
amplitudes were performed. The wave features resulting from the interaction of an ISW and double obstacles were found to differ
from those of single obstacle. The incident energy of an ISW was either reflecting back from the obstacles, dissipated through
turbulent mixing, or transmitted over the double obstacles. Reduction in wave energy increased as the intervals between obstacles
reduced. For two obstacles in different heights, energy dissipation was greater in the case with a higher obstacle ahead of
a lower one. However, the overall performance was dependent on the relative height of the obstacles, relative water depth
of the upper and bottom layer, in addition to the intervals between the obstacles. 相似文献