Exact and approximate solutions for fulfilment metrics in open pipeline order fulfilment systems

Open pipeline order fulfilment systems have emerged in sectors such as the automotive industry that offer a large number of product variants to the marketplace. In an open pipeline a customer can be fulfilled from anywhere in the system-by a stock product, by a product in the distribution system, by allocating a product in production or a product in the plan, or by supplying a product specially built to order (BTO). Here new results are presented to estimate the performance metrics for open pipeline systems. An exact expression is developed based on a Markov analysis to calculate the BTO proportion for any combination of the key system parameters-pipeline length, the variety level and the initial stock level. Approximation schemes are developed to estimate the pipeline and stock fulfilment proportions, the mean lead time and the mean stock level. The approximation schemes provide accurate estimates for a large range of systems. Specific issues that affect the estimation of performance metrics in low variety, open pipeline systems are discussed. The results presented provide generic insights for open pipeline systems design and management and provide a platform for further work in extending the applicability of open pipeline concepts

Using CERES-maize and ENSO as decision support tools to evaluate climate-sensitive farm management practices for maize production in the northern regions of Ghana

Open Access JournalMaize (Zea mays) has traditionally been a major cereal staple in southern Ghana. Through breeding and other crop improvement efforts, the zone of cultivation of maize has now extended to the northern regions of Ghana which, hitherto, were the home to sorghum and millet as the major cereals. Maize yield in the northern Ghana is hampered by three major biophysical constraints, namely, poor soil fertility, low soil water storage capacity and climate variability. In this study we used the DSSAT crop model to assess integrated water and soil management strategies that combined the pre-season El-Niño-Southern Oscillation (ENSO)-based weather forecasting in selecting optimal planting time, at four locations in the northern regions of Ghana. It could be shown that the optimum planting date for a given year was predictable based on February-to-April (FMA) Sea Surface Temperature (SST) anomaly for the locations with R2 ranging from 0.52 to 0.71. For three out of four locations, the ENSO-predicted optimum planting dates resulted in significantly higher maize yields than the conventional farmer selected planting dates. In Wa for instance, early optimum planting dates were associated with La Nina and El Niño (Julian Days 130-150; early May to late May) whereas late planting (mid June to early July) was associated with the Neutral ENSO phase. It was also observed that the addition of manure and fertilizer improved soil water and nitrogen use efficiency, respectively, and minimized yield variability, especially when combined with weather forecast. The use of ENSO-based targeted planting date choice together with modest fertilizer and manure application has the potential to improve maize yields and also ensure sustainable maize production in parts of northern Ghana

Weather-index based crop insurance as a social adaptation to climate change and variability in the Upper West Region of Ghana: Developing a participatory approach

Climate change and variability are major challenges to rain-fed crop production in Africa. This paper presents a report on a pilot project to test a concept for operationalizing weatherindex crop insurance as a social adaptation to the climate change and variability problem in the Upper West Region of Ghana. An analysis of long-term weather variables showed rising temperature of 1.7 oC over a period of 53 years as well as major shifts in rainfall patterns. Farmers face a new reality that cannot be addressed with their indigenous knowledge alone. The weather-index based crop insurance concept discussed herein was developed by combined effort of University of Ghana, the German International Cooperation (GIZ) and the Ghana National Insurance Commission (NIC) since 2010. This development was carried out via their filial, the Ghana Agricultural Insurance Pool (GAIP). The proposed concept sought to link various agricultural stakeholders such weather technical persons, farmers, agricultural extension officer, input dealers and other aggregators, and financial institutions as well as the insurance industry and focused on a participatory farmer led approach. The piloting of the concept was supported by the Climate Change and Food Security (CCAFs) project and was tested in the years 2012 and 2013 using a theatrical drama sketch in two districts in the Upper West Region of Ghana: Jirapa and Lawra. It was observed that training of farmers in the basic principles of weather (data collection, interpretation, etc.) facilitated the discussions on drought insurance, adding to the body of evidence supporting participatory design tools. The aim of this paper is to record this process and to put the results into recent context, through discussing them through the lens of insurance operations and research in Ghana. Ensuing discussions showed that although all stakeholders considered the participatory design tools to be meritorious, a number of logistical challenges were identified that need to be addressed for effective scaling. The study also highlighted the high spatial variability of rainfall in the Upper West region of Ghana, showing the necessity of satellite-derived rainfall products. Finally, the framework suggested in this report highlights the complexity and the institutional structures required to implement an effective insurance. In effect, our simple study has exposed the complexities and intricacies that must be overcome in establishing a sustainable insurance scheme in Ghana

Phylogeny and expression analysis of C-reactive protein (CRP) and serum amyloid-P (SAP) like genes reveal two distinct groups in fish

This work was funded by British Society of Animal Science/Genesis Faraday to both SAM and SB Immune control of energy reallocation in fish and a BBSRC Research Experience Placements (2010).Peer reviewedPublisher PD

Formal Derivation of Concurrent Garbage Collectors

Concurrent garbage collectors are notoriously difficult to implement correctly. Previous approaches to the issue of producing correct collectors have mainly been based on posit-and-prove verification or on the application of domain-specific templates and transformations. We show how to derive the upper reaches of a family of concurrent garbage collectors by refinement from a formal specification, emphasizing the application of domain-independent design theories and transformations. A key contribution is an extension to the classical lattice-theoretic fixpoint theorems to account for the dynamics of concurrent mutation and collection.Comment: 38 pages, 21 figures. The short version of this paper appeared in the Proceedings of MPC 201

Developing adaptation packages for West African agriculture while ensuring congruence with climate and RAPs

In the semi-arid region of the Sahel, climate change is already affecting the farming systems and these impacts are expected to heighten in the near to mid-century. Given the complexities and conflicting drivers at play and the foreseeable negative consequences on the livelihoods of the majority of farmers, it is worthwhile designing relevant adaptation packages that will alleviate these effects. In this study, we envision to assess the implications of implementing two adaptation packages within the context of three West African farming systems specifically located in Ghana (Navrongo), Mali (Koutiala) and Senegal (Nioro). The first adaptation package is composed of heat and drought tolerant species along with an economic and policy level intervention through the delivery of subsidies to acquire improved varieties. The second pack builds on the first but adds a fertilizer component (splitting and timing to account for extreme events) and a policy variable in the form of index-based insurance adoption. The design process included interactions with a diverse set of stakeholders. The outcomes of these adaptation options on current and future agricultural systems will shed light on the projected adoption rates of climate adapted-systems and show how these various adaptations affect the impacts of climate change, keeping congruence with the relevant representative agricultural pathways. (Texte intégral

Assessing the influence of land-use change on the variability of soil chemical properties in semi-arid zone of Ghana

The study aimed at providing basis to consider spatial variability in soil fertility to inform effective decision making in mineral fertilizer recommendations. The study area was classified into six land-use categories using a rural rapid appraisal technique with the aid of the farmers in the community, and by remote sensing satellite imagery (Quick bird). Land-use categories varied significantly in their nutrient, organic carbon content, and stock with coefficient of determination ranging from 0.14 to 0.46. This is reflected in decline in soil nutrient, organic carbon content, and stock with increasing number of years the land was put under cultivation except for permanently cultivated fields. Permanantly cultivated fields were located in the homestead and benefited from nutrient imports from the bush fields. The two farm types also differed significantly with respect to soil nutrients, organic carbon and stock. Soil organic carbon content was 8.2 and 4.5 g kg-1 for the homestead and bushfields, respectively. Soil organic carbon stock estimated for the two farm types were 125 and 74 t ha-1 for the homestead and bush fields, respectively. The study shows a distinct zone of nutrient enhancement within the homestead and bushfields that should be sampled separately when sampling the zone for fertilizer recommendations

How are gender equality and human rights interventions included in sexual and reproductive health programmes and policies: A systematic review of existing research foci and gaps

The importance of promoting gender equality and human rights in sexual and reproductive health (SRH) programmes and policies has been affirmed in numerous international and regional agreements, most recently the 2030 Agenda for Sustainable Development. Given the critical role of research to determine what works, we aimed to identify research gaps as part of a broader priority setting exercise on integrating gender equality and human rights approaches in SRH programmes and policies. A systematic literature review of reviews was conducted to examine the question: what do we know about how research in the context of SRH programmes and policies has addressed gender equality and human rights and what are the current gaps in research. We searched three databases for reviews that addressed the research question, were published between 1994-2014, and met methodological standards for systematic reviews, qualitative meta-syntheses and other reviews of relevance to the research question. Additional grey literature was identified based on expert input. Articles were appraised by the primary author and examined by an expert panel. An abstraction and thematic analysis process was used to synthesize findings. Of the 3,073 abstracts identified, 56 articles were reviewed in full and 23 were included along with 10 from the grey literature. The majority focused on interventions addressing gender inequalities; very few reviews explicitly included human rights based interventions. Across both topics, weak study designs and use of intermediate outcome measures limited evidence quality. Further, there was limited evidence on interventions that addressed marginalized groups. Better quality studies, longer-term indicators, and measurement of unintended consequences are needed to better understand the impact of these types of interventions on SRH outcomes. Further efforts are needed to cover research on gender equality and human rights issues as they pertain to a broader set of SRH topics and populations.Scopu