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PurposeThis research aims to determine to what extent uncertainties affected manufacturing enterprises' delivery performance, to analyse the performance of their contingency plans in dealing with uncertainties and to explore what technical and organisational factors affected managers' decisions to implement an uncertainty‐diagnosing model.Design/methodology/approachThe methodology included a literature review, postal questionnaire survey and telephone interviews.FindingsA total of 30 companies responded to the questionnaire, 56 per cent of which thought their systems worked well and 80 per cent reported that material shortages were responsible for tardy delivery performance. Tardy delivery was directly or indirectly caused by poor supplier delivery performance in the opinion of 92 per cent of respondents. Seven companies had developed an uncertainty‐diagnosing model. Not all companies needed to adopt the model.Research limitations/implicationsUncertainty and contingency plans were investigated in UK and Chinese organisations using MRP/MRPII/ERP systems. Therefore, the findings will be directly relevant to the organisations, but may be adapted to other similar organisations.Practical implicationsA detection method was proposed to determine the steps required for organisations to adopt the uncertainty‐diagnosing model.Originality/valueThe paper provides some empirical data on uncertainty and the contingency plans used in ERP‐controlled manufacturing environments in organisations in the UK and China. Data on uncertainty are scarce and this research gives further insights into the ways managers perceive and handle uncertainty.

Background: In many countries public and political interest exists on the communicable disease effects of prison crowding, prompting standards on minimum floor area of sleeping accommodation per person. Yet the extent and reliability of the worldwide evidence on the association between prison cell spatial density and communicable diseases is uncertain.Method: We conducted a systematic review of the peer-reviewed and grey literature for articles that reported on the association between prison cell spatial density and communicable disease effects in prisoners. Included studies were assessed for quality. A draft report was peer-reviewed by an independent researcher. Some revisions were made in light of reviewer comments.Findings: 3,532 articles were identified and 6 were included. Studies were conducted in the US (1980s), Pakistan (2003) and Nigeria (2012, 2013). Communicable disease effects/outcomes included pneumococcal disease/acute pneumonia, mycobacterium tuberculosis, infectious skin conditions, and communicable disease reporting to the prison clinic. There was mostly consistent evidence that cell spatial density is associated with communicable diseases. The associations and statistical precision observed suggest a 'slight' communicable disease impact of cell spatial density on prisoners. However, it is possible that these associations are due to confounding, bias and/or chance. Conclusion: The evidence provides some support that communicable disease effects are associated with cell spatial density but care should be taken in the interpretation of the findings. Socio-cultural demographic and historical differences between study populations examined also restrict the generalisability of findings. Key words: Communicable diseases; Population health planning, demography, needs assessment; Justice and ethics Key messages:1. There is paucity of research examining the association between prison cell crowding ('spatial density') and communicable disease effects 2. The small amount of evidence that exists provides some support that communicable disease effects in prisoners are associated with prison cell spatial density3. Care should be taken in the interpretation of these findings, as associations may be due to confounding, bias and/or chance.

AbstractElevated nitrate concentrations have been documented since the 1970s within the trans‐national Abbotsford–Sumas aquifer, situated in the central Fraser Valley of southern British Columbia, Canada, and northern Washington State, United States. Nitrate concentrations in excess of 10 mg/L NO3–N are commonly observed in the monitoring wells. A groundwater model is used in this study to conduct a particle tracking analysis to estimate groundwater travel times and compare these with groundwater ages determined from 3H/3He concentrations measured in several monitoring wells. Groundwater ages estimated from particle tracking show excellent agreement with measured ages (slope=1), although there is scatter (R2=0.76), reflecting the complexity of the travel pathways and ambiguities in groundwater ages because of mixing. An assessment of the efficacy of recommended nutrient management practices, which were implemented in 1992 to reduce nitrogen loading, suggests that wells shallower than about 20 m should be monitoring a decrease in nitrate concentration. However, persistent elevated nitrate concentrations even at shallow depths point to the lingering effects of a remnant manure–nitrate signature in combination with continued high loading.

In the changing competitive landscape and with growing environmental awareness, reverse logistics issues have become prominent in manufacturing organizations. As a result there is an increasing focus on green aspects of the supply chain to reduce environmental impacts and ensure environmental efficiency. This is largely driven by changes made in government rules and regulations with which organizations must comply in order to successfully operate in different regions of the world. Therefore, manufacturing organizations are striving hard to implement environmentally efficient supply chains while simultaneously maximizing their profit to compete in the market. To address the issue, this research studies a forward-reverse logistics model. This paper puts forward a model of a multi-period, multi-echelon, vehicle routing, forward-reverse logistics system. The network considered in the model assumes a fixed number of suppliers, facilities, distributors, customer zones, disassembly locations, re-distributors and second customer zones. The demand levels at customer zones are assumed to be deterministic. The objective of the paper is to maximize the total expected profit and also to obtain an efficient route for the vehicle corresponding to an optimal/ near optimal solution. The proposed model is resolved using Artificial Immune System (AIS) and Particle Swarm Optimization (PSO) algorithms. The findings show that for the considered model, AIS works better than the PSO. This information is important for a manufacturing organization engaged in reverse logistics programs and in running units efficiently. This paper also contributes to the limited literature on reverse logistics that considers costs and profit as well as vehicle route management.

AbstractSeasonal climate forecasts (SCFs) provide opportunities for pastoralists to align production decisions to climatic conditions, as SCFs offer economic value by increasing certainty about future climatic states at decision-making time. Insufficient evidence about the economic value of SCFs was identified as a major factor limiting adoption of SCFs in Australia and abroad. This study examines the value of SCFs to beef production system management in northern Australia by adopting a theoretical probabilistic climate forecast system. Stocking rate decisions in October, before the onset of the wet season, were identified by industry as a key climate sensitive decision. The analysis considered SCF value across economic drivers (steer price in October) and environmental drivers (October pasture availability). A range in forecast value was found ($0–$14 per head) dependent on pasture availability, beef price, and SCF skill. Skillful forecasts of future climate conditions offered little value with medium or high pasture availability, as in these circumstances pastures were rarely overutilized. In contrast, low pasture availability provided conditions for alternative optimal stocking rates and for SCFs to be valuable. Optimal stocking rates under low pasture availability varied the most with climate state (i.e., wet or dry), indicating that producers have more to gain from a skillful SCF at these times. Although the level of pasture availability in October was the major determinant of stocking rate decisions, beef price settings were also found to be important. This analysis provides insights into the potential value of SCFs to extensive beef enterprises and can be used by pastoralists to evaluate the cost benefit of using a SCF in annual management.