Lowland farming system inefficiency in Benin (West Africa):

This paper uses a directional distance function and a single truncated bootstrap approach to investigate inefficiency of lowland farming systems in the Benin Republic. First, we employed a dual approach to estimate and decompose short-run profit inefficiency of each farming system into pure technical, allocative and scale inefficiency and also into input and output inefficiency. Second, an econometric analysis of factors affecting the inefficiency was generated using a single truncated bootstrap procedure to improve inefficiency analysis statistically and obtain consistent estimates. In the short run, scale, allocative and output inefficiency were found to be the main sources of inefficiency. Based on inefficiency results, the inefficiency of lowland farming systems is the most diverse. Compared to a vegetable farming system, technical inefficiency is significantly higher if farmers switch to a rice farming system. Scale, allocative, output, and input inefficiency are significantly lower with an integrated ricevegetable farming system and there was high prevalence of increasing returns to scale in the integrated rice-vegetable farming system. Water control and lowland farming systems are complements and play a significant role in the level of inefficiency. Input inefficiency shows the difficulty that the producers face in adjusting the quality and quantity of seeds and fertilizers. The paper provides empirical support for efforts to promote an integrated rice-vegetable farming system in West Africa lowlands to increase food security. Keywords Lowlands . Inefficiency . Bootstrap . Beni

Learning in switching to organic farming

This paper estimates technical efficiency of organic and conventional dairy farming and its development over time. We control for possible selection bias and regional heterogeneity. The results suggest that technical efficiency measured as a ratio between actual and maximum obtainable output (relative to the peer group) at first diminishes when the conversion towards organic production starts. After 6-7 years from the switch, technical efficiency starts to increase again

BrainBasher: a BCI Game

Brain-computer interaction (BCI) is starting to focus on healthy subjects. This research adresses the effects of using this novel input modality to control a simple game, and also looks into the beneficial effects of bringing game elements into BCI experiments. A simple BCI game has been developed and evaluated with fifteen subjects using the Game Experience Questionnaire (GEQ) developed at the Eindhoven Game Experience Lab. Three variations of the game were evaluated for comparison: the original game with BCI input, one with keyboard input, and one with a more clinical look leaving out all extraneous information. The keyboard-controlled game was considered easy and boring, whereas using BCI for input resulted in a more challenging, immersive and richer experience. The design and additional information presented by the game also resulted in higher immersion compared to the clinical design

Towards a theory of technological mismatch: 1 - Consumption

In this paper, the relationship between technological change and employment is analysed using private consumption as a means to do so. Technological change will create new and more consumption opportunities by means of product and process innovation. This results in changes in consumption patterns and budget shares of consumer products. As a consequence of technological change and changing tastes, the production structure will be altered and therefore, changes in (the composition) of employment are inevitable. By using a narrow classification of products as well as occupations, it is possible to analyse the dynamics of adjustment and technological change and their impact on the composition of employment in terms of occupations/skills. Furthermore, obsolescence of products and skills, caused by technological change, can be related to each other by using an input-output framework. The decrease in the (real) consumption of industrial consumer goods has for instance lead to a decrease in the employment of industrial occupations. In addition, scientific/professional occupations seems to have replaced industrial occupations between 1980 and 1990 in the Netherlands. The development of information technology may be a reason for the relative decrease in the employment of commercial skills.economics of technology ;

Poly(vinyl chloride) polyacrylonitrile composite membranes for the dehydration of acetic acid

Composite membranes have been prepared consisting of a poly(vinyl chloride) (PVC) top layer on either a dense polyacrylonitrile (PAN) layer (bi-layer membrane) or a porous PAN support layer (normal composite membrane) and studied with respect to the dehydration of acetic acid. Especially, the influence of the surface porosity of the porous support layer on the selectivity and flux was studied and it was shown that the lower the surface porosity the higher the selectivity of the composite membrane, especially at high acetic acid concentrations in the feed. From the results it can be concluded that the support material does contribute to the selectivity. Despite the low surface porosity relatively high fluxes could be obtained. Using a feed composition of 80/20 wt.% acetic acid/water at 80°C selectivities of 182¿274 and fluxes of 0.56¿0.74 kg/m2-hr were obtained, and with a feed composition of 98/2 acetic acid/water selectivities of 206¿318 and fluxes of 0.14¿0.15 kg/m2-hr were obtained

Creating a typology of tobacco farms according to determinants of diversification in Valle de Lerma (Salta-Argentina)

The objective of this article is to identify typical tobacco farms according to determinants of diversification that can be used to explore possibilities of diversification in the province of Salta (Northwest of Argentina). National Agriculture Census data of 278 farms in the main tobacco production area of Salta were used for the analysis. The variables selected concerning determinants of diversification were: land area, irrigation, general capital goods and specific capital goods, ownership of land, education, off-farm work, and labour availability. The analysis of the principal components applied to 16 selected variables allowed to reduce the dimensionality of the data to four components. Those components were used to apply K-means cluster approach to classify the farms. Four clusters were determined. Cluster 1 and Cluster 2 are the largest clusters. These concern highly specialized tobacco farms. They differ regarding determinants for diversification due to different levels of education of the farmer and different levels of off-farm work. Both clusters are interesting for further analysis regarding diversification alternatives to maintain or improve income and to reduce soil degradation. Cluster 3 concerns large tobacco farms being somewhat less specialized than the farms in Clusters 1 and 2. Intensive tobacco production makes this group interesting for exploring diversification alternatives to improve soil conditions. Farms in Cluster 4 already have a high level of diversification with substantial livestock production. The presence of perennial pastures suggests a better soil management than the other clusters. This cluster looks appealing to investigate what can be done regarding diversification

Finite element models applied in active structural acoustic control

This paper discusses the modeling of systems for active structural acoustic control. The finite element method is applied to model structures including the dynamics of piezoelectric sensors and actuators. A model reduction technique is presented to make the finite element model suitable for controller design. The reduced structural model is combined with an acoustic model which uses the radiation mode concept. For a test case consisting of a rectangular plate with one piezo patch the model reduction technique is validated. The results show that the an accurate prediction of both the structural and acoustic response is predicted by the reduced model. The model is compact requiring small simulation times, which makes it attractive for control system design. Finally the control performances for both structural and acoustic error criteria are presented

Resilience of food companies to calamities - perceptions in the Netherlands

Calamities such as extreme droughts and trade or infrastructure breakdowns potentially hamper the continuity of individual food companies, as well as the continuity of food supply in Europe at large. There is a lack of insight into food companies’ resilience in case of cumulative calamities or calamities that did not happen before in recent history. In this context, an expert elicitation study among feed and food companies in the Netherlands was undertaken. Results show that lengthy or structural unavailability of electricity and a lengthy crisis of road transport are perceived as the most threatening calamities.Outcomes also show a relatively limited implementation of BCM (business continuity management) at company level. Complete BCM programs for top-3 calamities perceived to threaten the continuity of food supply in Europe are reported by 0% to 30% of the companies. For calamities perceived to be important for business continuity this is between 20% and 40%. In the field of risk management a leading role is attributed to the public sector for improving international governance and setting up a so-called masterplan with measures such as larger raw-materials stocks and broad sourcing. Findings suggest that further actions are needed, starting with prioritised calamities and the design of a masterplan. Yet, stakeholders are also urged to pro-actively “think the unthinkable