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61.
A key issue confronting our newer suburbs is the stance they should take towards efforts at regional cooperation and coordination of major policy areas. This article analyzes the preferences on this issue held by residents in a rapid growth suburb in the St. Louis metropolitan area. Through factor analysis, four identifiable dimensions of regionalist preferences were obtained from questionnaire responses--administrative cooperation, land-use cooperation, mass transit cooperation, and regional basic services cooperation. Correlational analyses between these dimensions of regionalist preferences and selected community status characteristics, social situation characteristics, and local political participation status of respondents reveal no systematic covariation. Thus municipal policies which influence the population mix within a community with respect to the life situation characteristics measured in this study are not likely to be useful instruments for influencing the preferences, pro or con, of the community towards regionalist policies. Further, local political participants are found to be representative of the larger community's regionalist policy preferences.  相似文献   
62.
Landscape structure indices for assessing urban ecological networks   总被引:9,自引:0,他引:9  
Analysis and planning of ecological networks is a relatively new phenomenon and is a response to fragmentation and deterioration of quality of natural systems. In urban areas, the problems of land use intransigence, political and jurisdictional issues create a difficult environment for implementing ecological networks. The specific questions addressed in this research program revolve around the viability of planning an ecological network in an urban landscape. The development and articulation of an ecological network plan was undertaken previously and in this paper, a series of assays of landscape structure are used to examine the viability of an ecological network in the Phoenix, Arizona urban area. Three principal analyses were utilized: (1) patch content analysis, (2) corridor content analysis, and (3) network structure analysis. Patch and corridor content analyses examined the internal characteristic and immediate context for each of the 89 ecological network elements. The network structure analysis incorporates a process for aggregating results of patch and corridor analyses and incorporates indicators that describe interrelationships between landscape elements. For each of these analyses the existing condition was compared to the optimal plan to demonstrate the level of change that can be expected. The results and conclusions of this research are that an ecological network plan provides modest but important improvement in ecological systems in the Phoenix urban area.  相似文献   
63.
We report the results of experiments designed to improve the efficacy of the solar disinfection of drinking water, inactivation process. The effects of periodic agitation, covering the rear surface of the container with aluminium foil, container volume and turbidity on the solar inactivation kinetics of Escherichia coli (starting population = 10(6) CFU ml(-1)) were investigated. It was shown that agitation promoted the release of dissolved oxygen from water with subsequent decrease in the inactivation rates of E. coli. In contrast, covering the rear surface of the solar disinfection container with aluminium foil improved the inactivation efficiency of the system. The mean decay constant for bacterial populations in foil-backed bottles was found to be a factor of 1.85 (std. dev. = 0.43) higher than that of non-foil-backed bottles. Inactivation rates decrease as turbidity increases. However, total inactivation was achievable in 300 NTU samples within 8 h exposure to strong sunshine. Inactivation kinetics was not dependent on the volume of the water container for volumes in the range 500-1500 ml.  相似文献   
64.
Elimination of beta-blockers in sewage treatment plants   总被引:2,自引:0,他引:2  
beta-Blockers are used to treat high blood pressure as well as patients recovering from heart attacks. In several studies, they were detected in surface water, thus indicating incomplete degradability of these substances in sewage treatment plants (STPs). In this study, we determined the sorption coefficients (K(D)) and degradation rates of the four beta-blockers sotalol, atenolol, metoprolol and propranolol in sludge from an STP operating with municipal wastewater. The sorption coefficients (K(D), standard deviations in brackets) were determined as 0.04(+/-0.035), 0.04(+/-0.033), 0.00(+/-0.023) and 0.32(+/-0.058) Lg(-1)(COD), and the pseudo-first-order degradation rate constants were estimated to be 0.29(+/-0.02), 0.69(+/-0.05), 0.58(+/-0.05) and 0.39(+/-0.07) Ld(-1)g(-1)(COD) for sotalol, atenolol, metoprolol and propranolol, respectively. These values translate into a typical elimination in STPs (sludge concentrations of 4g(COD)L(-1) and a hydraulic retention time of 6h) of 25%, 37%, 44% and 50% for sotalol, propranolol, metoprolol and atenolol, respectively. These results are also confirmed by measurements in two municipal STPs for atenolol, sotalol and propranolol. The estimated eliminations are slightly too high for metoprolol.  相似文献   
65.
Walk through questionnaires may be feasible tools to obtain data on the indoor environment in community studies. However, limited information is available regarding the reproducibility of the data obtained through these questionnaires. In this pilot study, two construction engineering students inspected ten dwellings twice by means of a standardized walk through questionnaire. The two engineering students inspected the dwellings independent of each other within two months. Time between the two visits varied between 14 and 40 days. The variables presented were based on information from the residents and inspection. The continuous variables recorded included number of rooms in the dwellings, room volume, length of filled shelves and textile area. The inter- and intra-observed variabilities were poorer for number of rooms and shelf factor than for the other variables. For the 3 of the 9 categorical variables based on inspection, the inter-observer comparison showed complete agreement with a kappa statistics of 1.0, these variables being condition of the window frames and construction of outside walls and roof. One of the categorical variables showed a kappa statistics of < 0.5, these variables being presence of basement and presence of condensation at windows. This study indicates a wide variation in observer variability between various items of a walk through questionnaire. Clear definitions of all the parts of the questionnaire are needed, as well as thorough training of observers.  相似文献   
66.
In this paper the migration routes of British Asian women living in London are examined. It is shown that British Asians connect with a myriad of landscapes abroad, including East Africa, India and Pakistan. These connections to past landscapes are mapped and considered here as valued environments of British Asian women in Britain. Through the mapping of their biographies, it is apparent that memories of other landscapes are embedded in environmental practices in Britain, therefore contributing to making the landscape in Britain inclusive and meaningful in the context of the South Asian migration. The maps of migration show the heterogeneity of landscapes experienced by the British Asian women. Memories of other lands manifest themselves in the UK. The effect of these memories on the South Asian home itself in the process of shaping diasporic geographies of belonging and being within the UK is illustrated.  相似文献   
67.
Basic types of foundations supporting old buildings in Saint Petersburg are reviewed. Fundamental relationships between the width and depth of embedment of the foundations and the number of stories are analyzed on the basis of field observations. Average pressures against the lower surfaces of the foundations are compared with design strengths adopted from modern standards for bed soils.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 13–15, September–October, 2004.  相似文献   
68.
Soil, bottom sediment, suspended sediment, and urban street dust and dirt samples from the Menomonee River Watershed, Wisconsin, were dispersed by ultrasound, fractionated and analyzed for the P content of each of three particle-size fractions. The major soil types in the watershed were used as a reference for comparing particle-size distribution and P content in urban street dust and dirt, and in sediments.Phosphorus level was found to be greater in the clay-sized particles than in the sand- or silt-sized particles of urban street dust and dirt samples, but 48% of the P was in the sand-sized fraction because of the predominance of sand-sized particles in these samples. The highest P level in the clay-sized fraction of the bottom sediments occurred at the site below a sanitary treatment plant (STP) outfall with secondary treatment capability. The P level found below a tertiary STP outfall was equal to the level found in agricultural areas. When using P level in sediment for locating areas of possible P input to the river, the clay-sized fraction of bottom sediments was more precise than P levels in unfractionated samples.  相似文献   
69.
Rapid 3D positioning and modeling in construction can be used to more effectively plan, visualize, and communicate operations before execution. It can also help to optimize equipment operations, significantly improve safety, and enhance a remote operator's spatial perception of the workspace. A new framework for rapid local area sensing and 3D modeling for better planning and control of construction equipment operation is described and demonstrated. By combining human-assisted graphical workspace modeling with pre-stored Computer-Aided Design (CAD) models and simple sensors (such as single-axis laser rangefinders and remote video cameras), modeling time can be significantly reduced while potentially increasing modeling accuracy.  相似文献   
70.
Fanger PO 《Indoor air》2000,10(2):68-73
Field studies demonstrate that there are substantial numbers of dissatisfied people in many buildings, among them those suffering from sick building syndrome (SBS) symptoms, even though existing standards and guidelines are met. The reason is that the requirements specified in these standards are rather low, allowing a substantial group of people to become dissatisfied and to be adversely affected. A paradigm shift from rather mediocre to excellent indoor environments is foreseen in the 21st century. Based on existing information and on new research results, five principles are suggested as elements behind a new philosophy of excellence: 1) better indoor air quality increases productivity and decreases SBS symptoms; 2) unnecessary indoor pollution sources should be avoided; 3) the air should be served cool and dry to the occupants; 4) "personalized air", i.e. a small amount of clean air, should be served gently, close to the breathing zone of each individual; and 5) individual control of the thermal environment should be provided. These principles of excellence are compatible with energy efficiency and sustainability.  相似文献   
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