48 research outputs found

    PRELIMINARY BOTANICAL ASSESSMENT OF PRODUCTION CHALLENGES OF CASHEW (ANACARDIUM OCCIDENTALE L.) IN LAFIA, NASARAWA STATE, NIGERIA

    Get PDF
    The aim of this study was to investigate the production and challenges of cashew farming in Lafia, Nigeria. The study area was divided into five zones. Fifty semi-structured questionnaires were administered to the farmers. The results showed that only males are engaged in cashew farming and slightly above 95% are married and just about 44% are aged between 21-40 y. Over 95% of farmers disclose that cashew production is seasonal; slightly above 73% disclose that diseases and pests are major challenges in cashew cultivation. Over 64% are of the opinion that these diseases and pests are responsible for yield reduction. Slightly above 52% disclose that yellow cashew is the most tasty and best for consumption. 52% of the farmers agree that 2017 is their best year of harvest because they were more involved in the management. 44% of farmers disclose that they do not apply chemicals and cultural practice in controlling diseases and pests, however majority agree that chemicals are useful in weed control. There was no agreement about the flowering and fruiting periods of cashew as 57% believe that cashew trees flower once, during the dry season and 65% disclosed that flowering occurs between January and March each year

    The role of the reactor size for an investment in the nuclear sector: an evaluation of not-financial parameters

    Get PDF
    The literature presents many studies about the economics of new Nuclear Power Plants (NPPs). Such studies are based on Discounted Cash Flow (DCF) methods encompassing the accounts related to Construction, Operation & Maintenance, Fuel and Decommissioning. However the investment evaluation of a nuclear reactor should also include not-financial factors such as siting and grid constraints, impact on the national industrial system, etc. The Integrated model for the Competitiveness Assessment of SMRs (INCAS), developed by Politecnico di Milano cooperating with the IAEA, is designed to analyze the choice of the better Nuclear Power Plant size as a multidimensional problem. In particular the INCAS’s module “External Factors” evaluates the impact of the factors that are not considered in the traditional DCF methods. This paper presents a list of these factors, providing, for each one, the rationale and the quantification procedure; then each factor is quantified for the Italian case. The IRIS reactor has been chosen as SMR representative. The approach and the framework of the model can be applied to worldwide countries while the specific results apply to most of the European countries. The results show that SMRs have better performances than LRs with respect to the external factors, in general and in the Italian scenario in particular

    Spatial organisation and population size of small Cucuteni-Tripolye settlements: Results of geomagnetic surveys in Baia and AdĂąncata, Suceava County, Bucovina, Eastern Romania

    Get PDF
    Geomagnetic research and drillings provide new results regarding settlement organisation and population size of three small settlements from the Pre-Cucuteni and the Cucuteni A-B period of Suceava County in Romanian Bucovina. In these settlements from different stages of the Cucuteni-Tripolye complex, domestic dwellings can be distinguished from clearly oversized (special?) buildings, which are situated in central locations and sometimes contain special inventories. Different principles of settlement organisation are visible, which each show far-reaching references to the Central Balkans, on the one hand, and the Bug-Dnieper interfluve on the other hand. Based on analogies with other Cucuteni-Tripolye sites, consistent populations with less than 200 inhabitants are reconstructed

    The transition towards a sustainable energy system in Europe: What role can North Africa's solar resources play?

    Get PDF
    Securing energy supply and speeding up the transition towards a reliable, sustainable, low-carbon energy system are among the major current and future challenges facing Europe. Importing dispatchable solar electricity from North Africa is considered as a potential and attractive option. Nevertheless, as things currently stand, the European Commission focuses mainly on the exploitation of the existing wind power potential in the North Sea, largely ignoring the solar power potential in the Sahara region of North Africa. After discussing the major challenges and issues facing Europe to achieve the assigned ambitious objectives, the paper emphasises the importance of North Africa's solar resources in helping Europe to successfully address the challenge of decarbonising its electricity system, in particular with regards to the security of supply and sustainability. Within these two major challenges, the paper explores the issues of access, barriers and opportunities. The paper highlights why the EU’s energy and climate goals will not be achievable without adequate grid expansion and grid-scale energy storage facilities, as well as other innovative measures to manage demand and ensure a secure energy supply. In this respect, the paper shows how the import of dispatchable electricity from North Africa via specific HVDC links could play a key role in helping the EU achieve its energy targets in a cost effective way without recourse to significant investments in transmission infrastructure and storage facilities. The paper then attempts to identify and analyze the main barriers that continue to inhibit the export of solar electricity from North Africa to Europe. Finally, to make the project more attractive and achievable in the near future, the paper proposes a systematic approach for setting up energy import scenarios. A promising import scenario is presented where energy import via Italy is shown to be a more viable and effective solution than via Spain.Peer reviewe

    Spatial interactions in agent-based modeling

    Full text link
    Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution of economic activities, - out of equilibrium. The Eurace@Unibi Model, an agent-based macroeconomic model with spatial structure, is used to illustrate the potential of such an approach for spatial policy analysis.Comment: 26 pages, 5 figures, 105 references; a chapter prepared for the book "Complexity and Geographical Economics - Topics and Tools", P. Commendatore, S.S. Kayam and I. Kubin, Eds. (Springer, in press, 2014

    A scorecard of progress towards measles elimination in 15 west African countries, 2001-19: a retrospective, multicountry analysis of national immunisation coverage and surveillance data.

    Get PDF
    BACKGROUND: The WHO Regional Office for the Africa Regional Immunization Technical Advisory Group, in 2011, adopted the measles control and elimination goals for all countries of the African region to achieve in 2015 and 2020 respectively. Our aim was to track the current status of progress towards measles control and elimination milestones across 15 west African countries between 2001 and 2019. METHODS: We did a retrospective multicountry series analysis of national immunisation coverage and case surveillance data from Jan 1, 2001, to Dec 31, 2019. Our analysis focused on the 15 west African countries that constitute the Economic Community of West African States. We tracked progress in the coverage of measles-containing vaccines (MCVs), measles supplementary immunisation activities, and measles incidence rates. We developed a country-level measles summary scorecard using eight indicators to track progress towards measles elimination as of the end of 2019. The summary indicators were tracked against measles control and elimination milestones. FINDINGS: The weighted average regional first-dose MCV coverage in 2019 was 66% compared with 45% in 2001. 73% (11 of 15) of the west African countries had introduced second-dose MCV as of December, 2019. An estimated 4 588 040 children (aged 12-23 months) did not receive first-dose MCV in 2019, the majority (71%) of whom lived in Nigeria. Based on the scorecard, 12 (80%) countries are off-track to achieving measles elimination milestones; however, Cape Verde, The Gambia, and Ghana have made substantial progress. INTERPRETATION: Measles will continue to be endemic in west Africa after 2020. The regional measles incidence rate in 2019 was 33 times the 2020 elimination target of less than 1 case per million population. However, some hope exists as countries can look at the efforts made by Cape Verde, The Gambia, and Ghana and learn from them. FUNDING: None

    Growing Smart Cities

    Get PDF
    As the world’s population becomes increasingly urbanised the problems of building sustainable cities also grows. Using Susan Stepney’s response, “Mighty Oaks from Little Acorns Grow”, to a science fiction story by Adam Marek titled “Growing Skyscrapers”, this chapter looks at what a living city of the future might look like, and how that might solve some of the problems of the control and development of cities. There is a long history of the application of systems thinking, cybernetics, and complex systems and the growth and control of cities. However, many problems still remain in the deployment and applications of these frameworks and methodologies, and in the potential consequences of their use. However, perhaps many of these could be solved by the development of a living city
    corecore