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101.
The development of an enormous culture gap, in which no individuals of advanced societies possess even a billionth of the non‐genetic information possessed by their entire society, has threatened a global collapse of civilisation. Critical parts of that gap must be rapidly bridged so that problems such as climate disruption, toxification of the Earth, loss of biodiversity and ecosystem services, and the decay of the epidemiological environment can be satisfactorily attacked. The essential need is to alter human behaviour to put society on a route to sustainability; one cheering development is a growing interest in the Millennium Assessment of Human Behaviour (MAHB), whose goal is to do just that.  相似文献   
102.
The paper reports an assessment of the soil and water in the coastal strip between Marsa Alam and Shalateen at the southern part of the Red Sea coast of Egypt. There is limited potential for agricultural development. There is a need for water re-use and some potential for tourism.  相似文献   
103.
Processing municipal and industrial wastes on land and particularly near inhabited centra has met with increased opposition. An apparent remedy to the problem is the establishment of such facilities offshore, hence various projects to build them on artificial islands. The paper examines a concrete proposal to locate such an island offshore from the Belgian Coast. Oceanographic and environmental aspects of the site are discussed, construction methods reviewed, erosion and corrosion effects looked at. The possibility of utilizing ocean power to provide the necessary operation energy is likewise considered.  相似文献   
104.
The effects of Lignosite#rm lignosulfonate, a refined lignosulfonate product that is obtained from the sulfite pulping process, on growth and survival of plants were investigated. Following applications of 0, 7500, 15,000 and 22,500 cm3#shm2 to 32 plots within a forest plantation, the following were monitored: (1) live aboveground biomass of vascular plants, (2) growth of Douglar fir (Pseudotsuga menziesii) and (3) lignosulfonate migration through the soil profile. Live aboveground biomass of woody vegetation was not affected, and that of herbaceous plants was significantly decreased only at the two greatest application rates. Growth of the Douglas fir trees was not significantly affected. Lignosulfonates disappeared from the soil profile at the same rate regardless of initial concentration. Although it is not practical to use this material as a herbicide in western Washington, land application of lignosulfonates may be environmentally more attractive than traditional disposal methods.  相似文献   
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Estimation is the first step in the project development process. Information technology provides an efficient platform for estimators to obtain quotations and specifications for their bid estimates. However, in practice, project overhead estimation relies heavily on the professional judgement and intuition of the estimators. This reduces the overall accuracy and reliability of the bid and a better understanding of the factors affecting project overheads is fundamental before any improved estimating methods can be devised. Unfortunately, the published literature on this topic is very limited. Using exploratory factor analysis, we aim to bridge the current knowledge gap by highlighting the principal factors affecting project overheads. Questionnaires detailing 27 variables were sent to quantity surveying managers of large contractors in Hong Kong. Seventy-nine valid responses were analysed by exploratory factor analysis. From the results, eight factors were extracted with their latent properties identified with reference to the expert opinions collected from telephone interviews. The findings clarify some misconceptions about the factors affecting project overheads and provide useful evidence for practitioners and researchers to understand project overheads. Estimators who address the identified factors when assessing future project overhead costs can improve the accuracy of their cost estimates and project budgets.  相似文献   
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Abstract

PLAN FOR REZONING THE CITY OF NEW YORK. A Report by Harrison, Ballard &; Allen. City Planning Commission. New York. 1950. 290 pp. maps, illustrations. $2.00.

CONTROLLED ACCESS EXPRESSWAYS IN URBAN AREAS—A symposium. Highway Research Board Bulletin No. 25. Washington, D. C., 1950. 45 pages, illustrated. 60 cents.

SOCIAL PRESSURES IN INFORMAL GROUPS. By Leon Festinger, Stanley Schachter and Kurt Back. Harper Bros., New York, 1950. x-930 pp. $3.00.

PRODUCTION OF NEW HOUSING. A Research Monograph on Efficiency in Production. By Leo Grebler. Social Science Research Council. New York 1950. ix+ 186 pp. $1.75.  相似文献   
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