A Finite Element Method for Distortional Buckling Analysis of Thin-Walled Members

This paper presents a method for distortional buckling analysis of thin-walled members without assuming longitudinal shape of buckling modes. In this method, the pure distortional elastic buckling loads and deformation modes are achieved by performing a linear buckling analysis of a specially constrained finite element model of the thin-walled member in ANSYS. The constraints on each cross-section are applied independently and can be divided into two parts. The first part, by which distortional buckling can be distinguished from local buckling, depicts the transvers deformation of a cross-section, while the second part originated from longitudinal displacement patterns of distortional modes is used to distinguish this type of buckling from global buckling. Transverse membrane extensions are permitted in the proposed distortional buckling mode. A numerical example is given to demonstrate the method

Corporate Social Responsibility on the Zambian Mining Industry

This report presents the different approaches to CSR in Zambia among mining companies whose activities have huge impacts on the environment. The mining related issues raised in the report include health and safety, security, education, migrant and settlement patterns, environmental management, poverty reduction, job creation, local economic development, gender and HIV/AIDS

Electronic Government Procurement (e-GP): A solution to institutional challenges in Zambia’s Medical Supply Chain or another technical solution?

Do technical solutions override or fast track institutional reforms? This study interrogates the extent to which Zambia’s newly introduced Electronic Government Procurement (e-GP) is addressing the procurement challenges [for essential drugs and medical supplies] in the Ministry of Health (MoH). A brain child of the Zambia Public Procurement Authority (ZPPA), the e-GP is but one of the components of the wider procurement reform agenda. The e-GP was introduced with the intention of enhancing efficiency, effectiveness and Value for Money (VfM) in public procurement. Since 2016, ZPPA has been piloting the approach in selected Procurement Entities (PEs), a combination of sector ministries and state parastatals. Based on review of project documentation, publicly available data, and interviews from key stakeholders; the study explores and interrogates the contextual and institutional challenges characterising the e-GP design and pilot implementation phases, and the extent to which these realities impact the achievement of the intended outcomes. A fair amount of information from interviewees was provided under conditions of confidentiality, thus individuals are not often identified. It is perhaps too early to ascertain the extent to which the e-GP is realising the intended objectives. This is partly explained by the project’s slow start, occasioned by delayed procurement which had knock - on effects on the overall project’s pace. An interrogation of the history and political economy of Zambia suggests however that it is the opaque challenges bordering on the political economy which is the single most binding constraint to reforms; defining the process, the pace and outcomes. The design of the e-GP was generic and non-participatory. There is no evidence to suggest that the process had provided opportunity for PE’s to define and customize the problems that mattered for them to be addressed by the e-GP. Instead, the e-GP seems to have been sold to PEs as a best practice solution. Because of the deep incentive fabric at both organizational and individual levels, the project seems to have some traction. Effort of various actors does not appear to be supportive of each, often latently contradicting each other. Project progress is held constant by the relative ability of the ZPPA to push some strands of work within some pilot PEs. This relative ability of the ZPPA shields the low levels of acceptance and questionable authority within PEs and among actors. Progress on the e-GP appears like a façade of success; suggestive of isomorphic mimicry

FAMILY DISORGANISATION AND MENTAL HEALTH IN A SOUTH AFRICAN MINING COMMUNITY

Family disorganisation and mental health in mining communities in South Africa are notunique, but it is the unique nature of mining communities that creates the risk factors and thetypes of service provisions that exacerbate the vulnerability of these communities (Gylfason,2001). At the same time, it is the nature of mental health that makes it a largely ignored healthproblem in these communities. These are burning and relevant issues and the focus of thisarticle

Corporate Social Responsibility in the Zambian mining sector: an overview of three distinctive operational eras

ABSTRACT Corporate Social Responsibility (CSR) within the extractive industry is a relevant and contentious issue globally. Issues pertaining to equality, human rights and sustainable development are pervasive throughout the economic, social and environmental arenas of the extractive industry. There is still not consensus on the definition of CSR regarding the measurement of performance or impact, or how to determine which of the various ‘developmental’ components of the concept – namely economic, social or environment – takes precedent over the other where there are competing interests. This article on CSR in the Zambian Copperbelt uses the experiences of mining communities as stakeholders who have gone through three types and eras of CSR practices within a generation. The Zambian Copperbelt has a history of operating under colonial rule, nationalisation and privatisation. The aim is to interrogate the CSR practices of the three identified eras in the history of the Zambian Copperbelt. The article is based on the findings from a mainly qualitative research approach. The research employed the survey procedure through focus groups, personal interviews and inputs from key informants.The findings are presented by a selection of narratives of CSR experiences from the Zambian Copperbelt mining communities. Consequently, an in depth discussion and analysis reflecting the effects of a CSR enabling environment in the three eras as experienced by community members follows. The paper concludes with a brief overview of the lessons learnt throughout the three eras. OPSOMMING Korporatiewe Sosiale Verantwoordelikheid (KSV) binne die ontginningsindustrie is 'n relevante en omstrede kwessie wêreldwyd. Kwessies met betrekking tot gelykheid, menseregte en volhoubare ontwikkeling is universeel ooglopend binne die ekonomiese-, sosiale- en omgewingsarenas van die mynsektor. Daar is steeds nie konsensus oor die definisie van KSV rakende die meting van prestasie of impak daarvan nie, ook nie hoe om te bepaal watter een van die verskillende "ontwikkelings" komponente van die konsep (naamlik die ekonomiese, sosiale of omgewingsaspek) bevoordeel moet word bo die ander, waar daar mededingende belange is nie. Hierdie artikel oor KSV in die Zambiese Koperstreek gebruik die ervarings van myngemeenskappe as belanghebbendes wat deur drie tipes en tydperke van KSV praktyke gegaan het, binne 'n generasie. Die Zambiese Koperstreek het 'n geskiedenis van die bedrywighede onder koloniale heerskappy, nasionalisering en privatisering. Die doel is om die KSV praktyke van die drie bogenoemde eras te ondersoek deur die geskiedenis van die Zambiese Koperstreek. Hierdie artikel is gebaseer op die bevindinge van 'n hoofsaaklik kwalitatiewe navorsingsbenadering en het gebruik gemaak van fokusgroepe, persoonlike onderhoude en insette deur sleutel informante. Die bevindinge word aangebied deur 'n seleksie van verhale rakende die KSV ervarings van die Zambiese Koperstreek myngemeenskappe. Daarna volg ?n in-diepte bespreking en ontleding rakende die gevolge van 'n KSV bemagtigende omgewing, in die drie eras soos ervaar deur lede van die gemeenskap. Die artikel sluit af met 'n kort oorsig oor die lesse wat geleer is oor die drie eras.https://doi.org/10.19108/KOERS.82.1.228

Early mortality in patients with kidney failure starting chronic dialysis in Zambia: a retrospective cohort analysis

Introduction: Dialysis is the primary kidney replacement therapy for patients with kidney failure in sub-Saharan Africa. We assessed the rates and predictors of early mortality in Zambian patients starting chronic dialysis. Methods: This retrospective study included all patients who started chronic haemodialysis (HD) or peritonealdialysis (PD) between 1 January 2017 and 31 August 2020 at the three largest public dialysis centres in Zambia. Data on clinical, laboratory and dialysis characteristics were extracted from medical records. The primary outcome of interest was the mortality rate at 90 days. Results: A total of 154 patients were included in the study; 43.5% were female and 32% were 50 years or older.The main causes of kidney failure were hypertension (59%), glomerulonephritis (10%), HIV/AIDS (10%) andunknown (8%). The mortality rate at 90 days was 12.3%. Of these, 42% were cardiovascular-related mortalities and 32% died of infection related to central venous catheters. The lymphocyte percentage of total white blood cells was lower in patients who died compared to survivors (12.7 vs 20.8%) and was an independent predictor of early mortality (OR 0.914, 95% CI 0.850–0.983; P = 0.015). Conclusions: Early mortality was high in Zambian patients starting dialysis, and a low lymphocyte percentage was a predictor of mortality

Biocompatible Herder for Rapid Oil Spill Treatment over a Wide Temperature Range

PresentationOil spills caused by damaged oil rigs, ruptured pipelines, and tankers can have immediate and long-term detrimental effects on marine systems and aquatic life. Herein we further develop the merit of an oil spill recovery technique called oil herding. A herder is an amphiphilic oil-collecting surfactant which is applied to spray around the oil spill areas and is able to retract oil slicks, transforming them from a large thin layer to a small thick bulk. This herding treatment greatly simplifies further in-situ burning and the recycle process. The natural konjac glucomannan (KGM) material could be functionalized and examined here as an oil herder, which has the great advantage of nontoxicity, biocompatibility, and adaptability. Moreover, functionalized KGM is a non-ionic surfactant with no Krafft temperature. The absence of Krafft temperature gives KGM surfactants the unique ability to retain surfactant ability at temperatures nearing 0 °C. It unlocks a new direction for efficient oil herders within low temperature water areas, especially for oil spills treatment in Arctic waters, in the offshore safety control

Traffic jam driving with NMV avoidance

n recent years, the development of advanced driver assistance systems (ADAS) – mainly based on lidar and cameras – has considerably improved the safety of driving in urban environments. These systems provide warning signals for the driver in the case that any unexpected traffic circumstance is detected. The next step is to develop systems capable not only of warning the driver but also of taking over control of the car to avoid a potential collision. In the present communication, a system capable of autonomously avoiding collisions in traffic jam situations is presented. First, a perception system was developed for urban situations—in which not only vehicles have to be considered, but also pedestrians and other non-motor-vehicles (NMV). It comprises a differential global positioning system (DGPS) and wireless communication for vehicle detection, and an ultrasound sensor for NMV detection. Then, the vehicle's actuators – brake and throttle pedals – were modified to permit autonomous control. Finally, a fuzzy logic controller was implemented capable of analyzing the information provided by the perception system and of sending control commands to the vehicle's actuators so as to avoid accidents. The feasibility of the integrated system was tested by mounting it in a commercial vehicle, with the results being encouraging

Tanzania's reptile biodiversity : Distribution, threats and climate change vulnerability

Assessments of biodiversity patterns and threats among African reptiles have lagged behind those of other vertebrate groups and regions. We report the first systematic assessment of the distribution, threat status, and climate change vulnerability for the reptiles of Tanzania. A total of 321 reptile species (including 90 Tanzanian endemics) were assessed using the global standard IUCN Red List methodology and 274 species were also assessed using the IUCN guidelines for climate change vulnerability. Patterns of species richness and threat assessment confirm the conservation importance of the Eastern Arc Mountains, as previously demonstrated for birds, mammals and amphibians. Lowland forests and savannah-woodland habitats also support important reptile assemblages. Protected area gap analysis shows that 116 species have less than 20% of their distribution ranges protected, among which 12 are unprotected, eight species are threatened and 54 are vulnerable to climate change. Tanzania's northern margins and drier central corridor support high numbers of climate vulnerable reptile species, together with the eastern African coastal forests and the region between Lake Victoria and Rwanda. This paper fills a major gap in our understanding of the distribution and threats facing Tanzania's reptiles, and demonstrates more broadly that the explicit integration of climate change vulnerability in Red Listing criteria may revise spatial priorities for conservation