Spatial and temporal variation in crop diversity in agroforestry homegardens of southern Ethiopia

A key assumption in many homegarden studies is that homegardens are ecologically and socio-economically sustainable due to their species diversity. The precise relation between diversity and sustainability is still heavily debated, however. A basic question is how diversity in homegardens can best be characterized in view of the various dimensions of species diversity and their variation in time and space. This paper assesses different types of species diversity in the homegardens of Sidama region of southern Ethiopia. In a survey of crop species in 144 homegardens a total of 78 cultivated crop species (excluding trees) belonging to 10 functional groups were recorded; there were on average 16 crop species and 8 functional groups per farm. Within homegardens, plots differ in species composition and crop diversity. Four types of homegarden systems are distinguished differing in both type and area-share of dominant species, relative orientation at subsistence or cash production and overall crop diversity. The gradual replacement of enset by maize and of coffee by more financially attractive cash crops khat and pineapple causes a decrease in overall crop diversity. Our data demonstrate that it is incorrect to consider homegardens as generic systems with a uniform distribution of species diversity: important within and between homegarden variation exists. Ecological and socio-economic sustainability is not just related to species diversity per se, but rather to more specific features such as presence of keystone species and diversity in functional species groups. Socio-economic sustainability in terms of adjustment to socio-economic change implies dynamics in species diversit

On fractional Choquard equations

We investigate a class of nonlinear Schrodinger equations with a generalized Choquard nonlinearity and fractional diffusion. We obtain regularity, existence, nonexistence, symmetry as well as decays properties.Comment: revised version, 22 page

Позиционирование изображений фотошаблонов в системах автоматизированного оптического контроля

Разработана система автоматизированного оптического позиционирования фотошаблонов интегральных схем, которая имеет высокие показатели помехоустойчивости и точности

Shared reading of children's interactive picture books

We report on a study of children and parents shared reading of interactive printed books. We investigated the differences between books with interactive features and books with expressive typography in order to evaluate which features within a book encouraged interaction between the reading participants and the book. 11 parent and child groups took part in the study that involved three observed reading sessions. From our observations we offer suggestions for the development of books and eBooks to encourage shared reading practices

Tangible landscapes and abstract narratives

© 2020 Association for Computing Machinery. The Tangible Landscapes range of interactive audiovisual and sculptural pieces offer audiences opportunities to explore abstract landscapes, recreating an embodied experience of the materials, through tangible interaction with found objects. The objects can contain sensors (tilt, orientation, movement, proximity, pressure, etc) which allow the audience to manipulate the video material through the sensors influencing the algorithms in the system. New meanings and new narratives can emerge from the audience interactions, explorations and interpretations, combining the individual and social, as well as the intimate and the spatial. Interactive art in general, and these pieces in particular, encourage and support the audience to create their own unique experiences, allowing for an individual sense of agency. The resulting patterns and images that emerge from the interaction, though these deliberate opportunities, a participative process of co-creating. This paper presents a range of these Tangible Landscape pieces, their relationship with earlier pieces and research, and placed in a context of artistic expression engaging with nature such as Landscape Art

Transport properties of Layer-Antiferromagnet CuCrS2: A possible thermoelectric material

The electrical, thermal conductivity and Seebeck coefficient of the quenched, annealed and slowly cooled phases of the layer compound CuCrS2 have been reported between 15K to 300K. We also confirm the antiferromagnetic transition at 40K in them by our magnetic measurements between 2K and 300K. The crystal flakes show a minimum around 100K in their in-plane resistance behavior. For the polycrystalline pellets the resistivity depends on their flaky texture and it attains at most 10 to 20 times of the room temperature value at the lowest temperature of measurement. The temperature dependence is complex and no definite activation energy of electronic conduction can be discerned. We find that the Seebeck coefficient is between 200-450 microV/K and is unusually large for the observed resistivity values of between 5-100 mOhm-cm at room temperature. The figure of merit ZT for the thermoelectric application is 2.3 for our quenched phases, which is much larger than 1 for useful materials. The thermal conductivity K is mostly due to lattice conduction and is reduced by the disorder in Cu- occupancy in our quenched phase. A dramatic reduction of electrical and thermal conductivity is found as the antiferromagnetic transition is approached from the paramagnetic region, and K subsequently rises in the ordered phase. We discuss the transport properties as being similar to a doped Kondo-insulator