Socially Inclusive Development : The Foundations for Decent Societies in East and Southern Africa

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The Decent Society Index Mark 2 : (1) Constructing the Index

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Bending and Web Crippling Interaction of Cold-formed Steel Members

The North American Specification has recently adopted a new web crippling approach for the Design of Cold-Formed Steel Structural Members (NAS, 2001). This approach is similar to what is currently in the Canadian S136 Standard (CSA, 1994). The current web crippling and bending interaction equations for single-web sections in the North American Specification (NAS 2001) are based on the previous web crippling methods that are contained in the American Iron and Steel Institute (AISI) Specification (AISI, 1996). As well, the moment component of the interaction equations was based on the previous reduced web strength method instead of the stress gradient approach that is now contained in the North American Specification (NAS, 2001). Using the available data found in the literature, regression analyses were carried out using the new web crippling equations and the stress gradient method to substantiate the current web crippling and bending interaction equations in the North American Specification (NAS, 2001). Based on the results of this investigation, new web crippling and bending interaction equations have been developed

Calibrations of Bolted Cold-formed Steel Connections in Bearing (With and Without Washers)

The bearing strength of bolted connections is treated differently in the two current North American Cold-Formed Steel Design documents, the AISI Specification in the USA (AISI 1996a) and the S136 Standard in Canada (CSA 1994). In the case of the S136 Standard (CSA 1994), only one expression is presented that applies to all bolted connections such as single and double shear, as well as, with and without washers. In the AISI Specification (AISI 1996a), however, a distinction is made between single shear and double shear connections and the use of washers. Contained in this paper are the calibration results of single and double shear cold-formed steel bolted connections with and without washers that failed in bearing. Calibrations were carried out in accordance with the AISI Commentary (AISI 1996b) to establish the resistance factors and respective factor of safety, which have already been adopted by the North American Specification (NAS 2001)

The North American Free Trade Agreemet and United States Employment.

The North American Free Trade Agreement (NAFTA) will create new opportunities for United States firms and workers while simultaneously protecting United States workers over a 15-year timeframe. The benefits of NAFTA include eliminating conditions that currently encourage or require United States firms to invest south of the border, establishing free trade in services, and eliminating non-tariff barriers which impede United States merchandise exports to Mexico. Furthermore, NAFTA would provide an improved and expanded regional trade and investment base resulting in a boost to the global competitiveness of US products. NAFTA would also increase trade liberalization with Mexico and maintain Mexico as a premier growth market for US exports and maintain the jobs those exports support. As NAFTA’s provisions are introduced, the provisions will be slowly phased in to protect US industries and workers. This will include tariff phase-outs, the NAFTA rules of origin, and a government to government dispute settlement procedure. Critics of NAFTA argue United States firms will move to Mexico due to weak labor and environmental standards. This belief, however, is a misconception. Standards in Mexico do not differ significantly from those in the United States and cooperative bilateral efforts on labor and environmental matters are occurring simultaneously to the NAFTA negotiations. The elimination of Mexico’s tariff and non-tariff barriers, Mexico’s local content, and export performance requirements, will eliminate motivation for United States manufacturers to move to Mexico. Nonetheless, international trade is necessary for the US economy and the US should engage in continental free trade through NAFTA

Are AGN Broad Emission Lines Formed by Discrete Clouds? --- Analysis of Keck High Resolution Spectroscopy of NGC 4151

We search for a direct signature of discrete ''clouds'' in the broad line region (BLR) of the Seyfert galaxy NGC 4151. For this purpose we apply cross correlation (CC) analysis to a high resolution KECK spectrum of the galaxy. No such signature is found in the data. In order for cloud models to be compatible with this result, there must be at least $\sim3\times10^7$ emitting clouds in the BLR, where the limit is based on simulation of a homogeneous cloud population. More realistic distributions increase the lower limit to above $10^8$. These numbers are an order of magnitude improvement on our previous limit from Mrk 335, where the improvement comes from higher S/N, broader lines, and refined simulations. Combined with the predicted upper limit for the number of emitting clouds in NGC 4151 ($10^6-10^7$), the derived lower limit puts a strong constraint on the cloud scenario in the BLR of this object. Similar constraints can be paled on models where the emission originates in streams and sheets. Thus, this investigation suggests that the BELs in NGC 4151, and by extension in all AGNs, are not made of an ensemble of discrete independent emitters.Comment: 18 pages, 8 figures, LaTeX aaspp style, to be published in MNRA