Land Classification: Providing an Explanation for the Decision Making Process

This paper considers the impact of technology on methods used to classify land potential. With developments in new technologies such as Expert Systems (ES) and Geographic Information Systems (GIS), McKeown (1987) proposes a new method by which to explain the decision making process for land classification to an end user. Consideration is given to McKeowns' concept and the literature reviewing both traditional land classification methods and ES and GIS systems.     

From Slavery to Abolition in Peru: Four Recent Contributions

Agentes de su propia libertad. Los esclavos de Lima y la desintegración de la esclavitud, 1821–1854. By CARLOS AGUIRRE. Lima: Fondo Editorial Universidad Católica, 1993. Pp. 333.

Slavery and Abolition in Early Republican Peru. By PETER BLANCHARD. Delaware: Scholarly Resources, 1992. Pp. xx, 247.

Paying the Price of Freedom: Family and Labor among Lima's Slaves, 1800–1854. By CHRISTINE HÜNEFELDT. Berkeley: University of California Press, 1994. Pp. xi, 269.

Safari africano y compra‐venta de esclavos para el Perú (1412–1818). By FERNANDO ROMERO. Lima: IEP‐UNSCH, 1994. Pp. 275.     

TECHNOLOGY AND COLOUR DEVELOPMENT OF HISPANO-MORESQUE LEAD-GLAZED POTTERY

Lead-glazed pottery from the medieval workshop of Les Olleries Majors (Paterna, Spain) has been studied by Mössbauer spectroscopy, X-ray diffraction, X-ray fluorescence and optical spectroscopy. Yellow, brown and honey-coloured glazes occur on pots glazed on only one surface. They have virtually identical compositions and transmittance spectra, their apparent differences in colour are due to the colours of the underlying pastes. Yellow glazes occur on cream-coloured calcareous bodies, honey-coloured glazes occur on less calcareous bodies with some development of hematite, while brown glazes occur on red siliceous cooking-pots. Green glazes are found on pots glazed on both surfaces; the glazes trapped CO₂ evolved by decomposing carbonates, resulting in an internal reducing environment. This caused the reduction of iron to the ferrous state which coloured the glaze green by diffusion.     

QUANTITATIVE ANALYSIS OF COPPER-TIN BRONZES BY MEANS OF GLOW DISCHARGE OPTICAL EMISSION SPECTROMETRY

Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed.     

AGGREGATION ERROR EFFECTS ON THE DISCRETE-SPACE p-MEDIAN MODEL: THE CASE OF EDMONTON, CANADA

The spatial analysis literature recognizes three sources of aggregation error, termed Source A, Source B, and Source C, which affect models relying on distance measurements between populations and facilities. We consider these effects with respect to aggregating from census enumeration areas to census tracts, on a popular location model. We identify a further source of aggregation error, which we dub Source D error, arising from the representation of facility sites by discrete points. Source D effects are of the same magnitude as Source A and B combined, much greater than Source C effects. Source D error is further significant, because, unlike Source A and B error, it can be eliminated only by disaggregating .
La littérature sur Vanalyse spatiale reconnaît trois sources d'erreur d'agrégation appelées erreurs de source A, B, et C. Ces erreurs influencent les modèles qui reposent sur des mesures de distance entre des populations et des installations. On considère les effets d'agrégation des secteurs de dénombrement en secteurs de recensement sur un modèle de localisation courant. On identifie une quatrième source d'erreur d'agrégation appelée erreur de source D. Cette erreur découle de la représentation des sites des installations par des points discrets. Ses effets sont du même ordre de grandeur que ceux des sources A et B combinées et beaucoup plus grands que les effets de source G. L'erreur de source D est d'autant plus significative à cause du fait que, contrairement aux erreurs de source A et B, elle ne peut être éliminée que par la désagrégation .     

Beyond Gender Roles? Conceptualizing the Social and Economic Lives of Rural Peoples in Sub-Saharan Africa

The repeated failure to design and appropriately target policies and interventions which address the needs of rural peoples in Africa suggests that something may be wrong with our understanding of the way that these peoples live their lives. Perspectives which focus on intra-household processes, and on gender issues in particular, represent useful advances in the way that the social and economic lives of Africa's rural peoples are conceptualized. However, this article questions the value of adopting development planning, policy and project approaches based on the rigid identification of `gender roles'. By reference to field research undertaken in northern Ghana, the paper aims to demonstrate that other social constructs, such as marital status and seniority, may be as important as gender in determining the roles and status of individuals in African rural societies. The article concludes by highlighting a number of practical implications of this finding in terms of the structuring of development-oriented research and the targeting of policy and interventions.     

Food Security in India: Measures,Norms and Issues

Although assessments by conventional macro measures show considerable improvement in food security in India, the levels of cereal consumption and calorie intake of even the general population are still below the normative threshold limits. This article brings out the dynamics of changes in institutional and production conditions and their implications for consumption patterns and food security at the micro level. The article uses empirical evidence to raise a number of issues, and calls for emphasis on investment in human capital by way of improvements in food and calorie intake for efficiency and economic growth.     

Reducing Toxic Chemical Releases and Transfers: Explaining Outcomes for a Voluntary Program

Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.