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21.
This paper investigates the effect of environmental features on house values while focusing on the interactions between landscaping attributes and home buyers' profile. The originality of this study rests on the assumption that, while neighbourhood characteristics translate into distinct sub-markets and primarily set the structure of house prices, individual home buyers' preferences, under specific market conditions, also affect values. The study benefits from two distinct, although related data sets on the single-family segment of Quebec City's housing market: while landscaping features were obtained via an extensive field survey of houses sold between 1993 and 2000, a detailed phone survey of related homeowners' family status, age and income profiles is being conducted since 2000. Findings suggest that household profile and structure do shape landscaping preferences and that utility patterns of homeowners may be best understood by looking at interactions between the two sets of variables. Considering that population aging is a major issue for economic and social planners, such a conclusion should be accounted for in housing policy design.  相似文献   
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Work is being undertaken to produce an uncooled pyroelectric infra-red detector array which incorporates within its structure, an array of radiation collectors made by the bulk micro-machining of silicon. Development aspects of the processing route are presented here.  相似文献   
24.
Our original article (Chinyio et al., 1998a) ‘A needs based methodology for classifying construction clients and selecting contractors’, Construction Management and Economics, 16 (1), 91-98 discussed the empirical classification of construction clients and illustrated a new methodology for selecting contractors. The techniques we adopted have not been applied in a construction scenario before and thus their implementation may face teething difficulties as differences between construction and the disciplines from which the techniques were adopted are ironed out. Due to brevity we did not highlight some of the potential problems their implementation would encounter, as we could not explain everything on the subject matters in one article. Skitmore and Mills (1999) in a comment, Construction Management and Economics, 17 (1), 5-7, highlighted some anticipated difficulties and posed some insightful questions concerning the applicability of our concepts. From an optimistic perspective we have addressed most of the sundry issues raised by Skitmore and Mills wherein ‘Decision Analysis’ was reviewed as a basis for responding to the comments.  相似文献   
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The hydrolysis of chitin by Serratia marcescens chitinase was studied as part of ar overall project to develop a chitin waste treatment bioconversion scheme. Hydrolyses were conducted with automatic pH control in stirred flasks. Parameters varied were temperature, enzyme activity, and chitin particle size and concentration. A temperature of 30°C is suitable. Hydrolysis increases with increasing enzyme activity and chitin slurry concentration, and with decreasing particle size.  相似文献   
27.
Quantitative data were obtained for total carbonyls, total monocarbonyls, methyl ketones, saturated aldehydes, 2-enals and 2,4dienals from fresh, reduced surface flora (Dip) and inoculated muscle samples incubated at the optimal growth temperature of the respective bacteria. Individual monocarbonyl compounds were identified by thin-layer and gas liquid chromatography. Micrococcus cryophilus, Pseudomonas fluorescens and Staphylococcus aureus decreased total carbonyls by 57, 18 and 43%, respectively, and total monocarbonyls by 53, 20 and 33%, respectively. Pediococcus cerevisiae increased the total carbonyl and total monocarbonyl content by 70 and 71%. Concentrations of carbonyls in the control samples were directly related to temperature of incubation. Methyl ketones, saturated aldehydes, 2-enals and 2,4dienals were decreased by M. cryophilus, Ps. fluorescens and S. aureus but each monocarbonyl class was increased by P. cerevisiae.  相似文献   
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Abstract

Multichannel sea surface tempratures (MCSSTs) have been produced operationally on a global basis from AVHRR data since November 1981. Although the basic technique has been unchanged for over S years, refinements and modifications to handle special situations (e.g. volcanic and sandstorm aerosols) are under development and a cross-product (nonlinear) procedure for atmospheric corrections has been tested. The aerosol optical depth estimates have been made experimentally for about a year using AVHRR data from channel-1, and special cloud screening techniques have been developed to differentiate between clouds and aerosols.  相似文献   
30.
The papers in this volume generally represent new developments in anthropology and cultural theory. Inevitably, in an evolutionary flowering, divergence can occur. Two of the papers represent a very new approach to theory for anthropology. This note discusses issues related to construction of theory that distinguish those papers.  相似文献   
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