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71.
Elizabeth C. Delmelle 《Geographical analysis》2021,53(1):148-156
The fiftieth anniversary of Geographical Analysis occurs for many quantitative human geographers at an exciting era of new and exciting sources of data and computational advancements. However, it also represents a crossroads where excitement to quickly capitalize upon these new data sources and methods risks reverting the discipline back to its abstraction‐rich and overly generalized roots, erasing much progress made in the pages of this journal that advocated for the recognition of individual differences and need for alternative and even qualitative data sources. In this commentary, I reflect on what we can do over the next 50 years to ensure that the journal is producing research that is socially impactful and better able to explain the messiness of social reality. 相似文献
72.
The raw material used largely determines the type and quality of porcelain produced. Twenty-three raw materials used for making Ding, Xing, Gongxian and Dehua porcelain bodies were studied using principal component analysis. Results show that for Dehua wares, only one raw material was used. For Ding wares, although there were many possible raw materials, the use of one alone is unlikely. Lingshan clay was the main raw material but it has to be mixed with other raw materials: Pinjiawa clay, quartz, feldspar and dolomite. The Xing pieces can be divided into three groups and Gongxian wares into two groups, which are discussed in detail. 相似文献
73.
Nabaitu J Bachengana C Seeley J 《Africa : journal of the International Institute of African Languages and Cultures》1994,64(2):243-251
"The aim of this study was to examine people's beliefs about the causes of marital instability in a rural population cohort in south-west Uganda. Results from a baseline survey of HIV-1 infection in the cohort of over 4,000 adults (over 12 years old) showed a twofold increase in risk of infection in divorced or separated persons when compared with those who are married. A purposive sample of 134 respondents (seventy-two males, sixty-two females) selected to represent different ages, religions and marital status were asked in semi-structured interviews to comment on the reasons for continuing marital instability in their community. The most common reasons suggested for marital instability were sexual dissatisfaction, infertility, alcoholism and mobility....HIV infection was not mentioned as a direct cause of separation, but a small independent study revealed that seven out of ten couples separated on learning of a positive HIV test result of one or both partners. Marital instability is not uncommon in this population; there is evidence that HIV infection is making the situation worse." (SUMMARY IN FRE) 相似文献
74.
Several samples of geological stones from statuary pedestals found in various archaeological sites in Cyprus have been characterized using non-contact laser infrared photothermal radiometry. Thermal diffusivities and effective optical absorption coefficients were calculated using a one-dimensional thermal-wave model. The mean values and standard deviations were tabulated and comparisons were made with lithographic and petrographic studies of the samples. Good correlations were found, thus demonstrating that laser photothermal archaeometry is a promising methodology for the accurate, potentially non-destructive and convenient characterization of the origins of ancient stones in Cyprus and other geological and archaeological sites. 相似文献
75.
D. E. NELSON G. CHALOUPKA C. CHIPPINDALE M. S. ALDERSON J. R. SOUTHON 《Archaeometry》1995,37(1):151-156
Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP. 相似文献
76.
A Roman archaeological site in northern Spain (La Maja, province of La Rioja) includes pottery workshops, part of an important ceramic industry that developed from about the first century BC to the first century AD. A geophysical study was planned to determine the extent of the industrial complex in the vicinity of an excavated kiln. Magnetic observations were done on a grid of 30 × 36m, with a sampling interval of 1m. Two dipolar-shaped anomalies were found: one in the north-east and the other in the south-west of the area. Low-pass and band-pass filters were used in the Fourier domain to enhance the characteristics of the magnetic data and to remove noise and undesirable shallow features. Three-dimensional polygonal prisms were used to model the magnetic anomalies based on palaeomagnetic measurements performed over an uncovered kiln that helped to constrain the induced and remanent parameters of the magnetizing fields. 相似文献
77.
ABSTRACT. A large proportion of regional production takes place in nontraded goods and services. In addition, significant productivity increases can be observed in some segments of this sector. Starting from these two empirical observations we construct a model of growth in a two-region setting with factor mobility. The growth process is based on endogenous technological change in the nontraded input sector, whose output serves as an input in the production of one of the two final goods, the so-called industrial good. We consider two extreme cases, one with locally limited, the other with interregional knowledge spillovers. Conditions are established under which interior solutions with production of local inputs and steady-state growth in both regions result, and others under which we find a core-periphery pattern with growth concentrated in one region only. The stability of the equilibria is discussed by considering the transition processes. Finally, it is shown that catching-up as well as leapfrogging may occur, if new technologies become available. 相似文献
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Random Time Sampling is an innovative data collection method which has potential for adaptation and use by geographers. Individual pocket-sized programmable beepers were used in a pilot study of the uses of time by older households and older people's attitudes to different activities. Random beeps were used to prompt individuals living in eleven Melbourne suburbs to record time use data in diaries over a period of a week. The method proved extremely effective and reliable, and many participants reporting that they enjoyed the exercise. 相似文献