The Doubly Stochastic Single Eigenvalue Problem: An Empirical Approach

The doubly stochastic single eigenvalue problem asks what is the set DSn of all complex numbers that occur as an eigenvalue of an n-by-n doubly stochastic matrix. For n \u3c 5, this set is known and for the analogous set for (singly) stochastic matrices, the set is known for all n. For Pk , the polygon formed by the k-th roots of unity, Unk=1 Pk ⊆ DSn, as is easily shown. For n \u3c 5, this containment is an equality, but for n = 5, the containment is strict (though it is close). Presented here is substantial, computational evidence that the containment is an equality for 6 ≤ n ≤ 10 and for what DS5 actually is

Finance for on-farm investments in dairy production in Kenya

About 2 million rural households in Kenya produce milk. With about 1800 liters per cow and year, average annual milk production per cow on smallholder dairy farms is low. As a result, production costs per kilogram of milk are high, and profit margins for many farmers are slim. Low cow productivity is also associated with high greenhouse gas (GHG) emission intensity. In 2010, Kenya’s livestock emitted about 16.6 million tonnes of carbon dioxide equivalents (CO2e), of which about 20% was from dairy cattle

Relationships Between Motivational Orientations and Participants\u27 Perceptions of an Electronic Distance Education Learning Environment

The purpose of this study was to investigate the relationships between students\u27 motivational orientations and their perceptions of an electronic distance education (EDE) environment. Subjects were 156 participants (81 women, 75 men; 83 undergraduates, 73 graduate students) enrolled in Utah State University\u27s electronic distance education system, Com-Net. A comparison group was also utilized, that consisted of 85 participants (64 females, 21 males; 34 undergraduates, 51 graduates) from rural Utah enrolled in Utah State University extension programs. These students were from seven classes which were taught by the traditional method with an instructor physically present. Correlation coefficients were computed to test the hypotheses of this study. The independent variables (motivational orientations), as measured by Boshier\u27s Education Participation Scale, were correlated with the dependent variables (satisfaction, material environment, involvement, and extension) as measured by the Learning Environment Inventory and the College and University Classroom Environment Inventory. One-way analyses of variance were computed to explore possible relationships with independent variables not included in the original hypotheses. Multiple regression analysis was used with satisfaction as the independent variable to look for possible explanations of student satisfaction. The participants in this study differ significantly from the norms in their motivational orientations in the areas of professional advancement and cognitive interest. Although the null hypotheses were rejected the relationships were weak, and there appears to be little practical relationship between motivational orientations and participants\u27 satisfaction. These results suggest that participant satisfaction is largely independent of initial motives that impel individuals to participate. Motivational orientations\u27 minimal impact on participant satisfaction suggest that the sources of variation in satisfaction lie elsewhere. There may be other internal variables that affect satisfaction, but more probably there are external variables that greatly influence satisfaction

Access to and supply of finance for enhancing dairy productivity

The dairy sector is the largest single sub-sector within Kenya‘s agricultural sector, contributing about 14% of agricultural GDP and 3.5% of total GDP. With population growth, urbanization and rising incomes, consumption demand for milk is projected to increase significantly. If this is met from domestic production, greenhouse gas emissions from the dairy sector will increase. A proposal is being developed for submission to the emerging sources of climate finance for a dairy Nationally Appropriate Mitigation Action (NA-MA) in Kenya that aims to promote low-emission development of Kenya’s dairy sector. One of the main proposed approaches to reducing GHG emissions from the dairy sector is to increase the productivity of dairy cows and lower the intensity of GHG emissions (kg CO2e per kg milk). Increasing productivity on smallholder farms will require improved access to technical extension and advisory services, improved market linkages through dairy cooperatives, and finance for investments by farmers and dairy cooperatives. This report assesses access to credit finance by smallholder farmers and cooperatives, and the supply of finance from financial institutions and other sources, and identifies potential modalities for increasing access to finance to enable investments by smallholder dairy farmers and dairy cooperatives. Although participation in informal financial institutions is prevalent, the vast majority of dairy farmers have never had a loan from a formal financial institution. Constraints include lack of a perceived need for a loan, fear of loss of assets, inability to repay, lack of collateral and/or lack of financial records/credit history. The limited visibility of farmers‘ financial track record, and awareness of production and market risks and hence higher transaction costs are key barriers for financial institutions in financing dairy producers. Among households that have had a loan from a formal financial institution, SACCOs are the most common source. Dairy cooperatives also use their own funds, and funds from SACCOs and commercial banks to finance capital investments and operating expenses, and some have established relationships with financial institutions to facilitate payments for milk intake as well as other inputs and services. Loans to the dairy sector by formal financial institutions constitute a very small proportion of total loans for most financial institutions, except for SACCOs with a strong farmer base. Compared to commercial banks, SACCOs are better placed to serve dairy farmers, and their loan products have lower interest rates and more flexible terms. However, SACCOs are constrained in their ability to utilize international sources of finance, such as climate finance, and commercial banks, which typically focus on small and medium enterprises, are better placed to meet the financial needs of dairy cooperatives. Concessional loans, credit guarantees and technical assistance are all relevant mechanisms for supporting financial services to the dairy sector. Financial institutions highlighted in particular the need for technical assistance with developing financial products suited to the dairy sector’s needs and with application of information and communication technologies to provide supply chain financing solutions. The dairy and financial sectors in Kenya are both areas of dynamic innovation. Further research should focus on identifying and evaluating existing financial innovations in the sector, and assessing the potentials for up-scaling. Although many innovations make use of the relatively better supply of data and in-formation for decision-making and structured supply chain relationships in the formal sector, the majority of dairy farmers supply informal milk value chains and have limited links with formal financial institutions. The financial relationships and potential for innovations to promote financial inclusion outside the formal dairy and financial sectors should be a focus for future research

The PiSpec: A Low-Cost, 3D-Printed Spectrometer for Measuring Volcanic SO2 Emission Rates

Spectroscopy has been used to quantify volcanic gas emission rates, most commonly SO2, for a number of decades. Typically, commercial spectrometers costing 1000s USD are employed for this purpose. The PiSpec is a new, custom-designed, 3D-printed spectrometer based on smartphone sensor technology. This unit has ≈1 nm spectral resolution and a spectral range in the ultraviolet of ≈280–340 nm, and is specifically configured for the remote sensing of SO2 using Differential Optical Absorption Spectroscopy (DOAS). Here we report on the first field deployment of the PiSpec on a volcano, to demonstrate the proof of concept of the device’s functionality in this application area. The study was performed on Masaya Volcano, Nicaragua, which is one of the largest emitters of SO2 on the planet, during a period of elevated activity where a lava lake was present in the crater. Both scans and traverses were performed, with resulting emission rates ranging from 3.2 to 45.6 kg s−1 across two measurement days; these values are commensurate with those reported elsewhere in the literature during this activity phase (Aiuppa et al., 2018; Stix et al., 2018). Furthermore, we tested the PiSpec’s thermal stability, finding a wavelength shift of 0.046 nm/∘C between 2.5 and 45∘C, which is very similar to that of some commercial spectrometers. Given the low build cost of these units (≈500 USD for a one-off build, with prospects for further price reduction with volume manufacture), we suggest these units hold considerable potential for volcano monitoring operations in resource limited environments