FSA field test report, 1980 - 1982

Photovoltaic modules made of new and developing materials were tested in a continuing study of weatherability, compatibility, and corrosion protection. Over a two-year period, 365 two-cell submodules have been exposed for various intervals at three outdoor sites in Southern California or subjected to laboratory acceptance tests. Results to date show little loss of maximum power output, except in two types of modules. In the first of these, failure is due to cell fracture from the stresses that arise as water is regained from the surrounding air by a hardboard substrate, which shrank as it dried during its encapsulation in plastic film at 150 C in vacuo. In the second, the glass superstrate is sensitive to cracking, which also damages the cells electrostatically bonded to it; inadequate bonding of interconnects to the cells is also a problem in these modules. In a third type of module, a polyurethane pottant has begun to yellow, though as yet without significant effect on maximum power output

Food supply chain management and contracting: improving conditions for small-scale paprika farmers in central Malawi

Global population growth and increasing incomes across the world are resulting in consumers’ rising demand for quality and diverse foods. Trade liberalisation and modernisation of production, processing and distribution systems enable agro-food companies to quickly access raw materials from farmers. Thus, efficient supply chains have a key role to play in the global marketing of foods. They also significantly contribute to satisfying consumers’ needs and responding to emerging food trends. The organisation of the product flow among farmers, buyers, processors and customers through contracts represents an increasingly important marketing channel in modern food supply chains due to its potential to decrease costs and increase profits for the participants in the chain. However, vulnerable small-scale farmers in developing countries such as Malawi are often excluded from the benefits of the transformed food industry. Contract farming is recognised as one of the tools linking farmers with modern agro-food supply chains, which enables Malawian small-scale farmers to improve their livelihoods. This study explored, examined and addressed the key challenges in contract farming arrangements in the paprika supply chain in Central Malawi. A mixed methods approach was used to collect qualitative and quantitative data. A total of 428 household questionnaires were administered to contracted small-scale paprika farmers in two Malawian districts. These were supplemented with ten focus group interviews with small-scale farmers, 21 semistructured stakeholder interviews, ten expert semi-structured interviews, field observations and two focus group discussions with stakeholders. The study found that the quality of communication among the key participants in the paprika supply chain was low. Furthermore, the enabling environment provided limited access to input and services for small-scale farmers. The paprika contract secured quality seeds and extension services to contracted small-scale farmers. Nevertheless, the provision of fertilisers, pesticides, chemicals, storage and transportation services were not part of the Malawian contract. Poor contract design and side-selling practices posed a threat to the chain’s efficiency and sustainability. Small-scale farmers gained benefits from the contracted production but contracting itself was not a sufficient strategy to sustain their livelihoods throughout the year. More dedicated involvement of farmers’ organisations and NGOs in empowering small-scale farmers, and the Government’s presence through the national Contract Farming Strategy could contribute to better efficiency and sustainability of the chain. The study’s main contributions include: adding new evidence on contract farming performance in developing countries; highlighting the importance of contract design and the issue of side-selling for improved contracting conditions, and demonstrating how dissemination of the study’s findings can be incorporated into study design to increase the validity, rigour and impact of the research

Is It All About the Money? Extent, Reasons and Triggers for Side-selling in Malawi’s Paprika Supply Chain

The purpose of this paper is to advance the knowledge on side-selling. The case study of the paprika supply chain in Central Malawi showed that 36.9% of small-scale farmers engaged in side-selling. It was projected that the focal company lost between 19.9% to 44.6% of paprika due to side-selling. The main reason for side-selling was the higher price offered by local vendors. Binary logit regression indicated that the geographical location, education and income levels, distance to the collection point, a negative impact of contracting on livelihoods, membership in farmers' association and assistance from the Government significantly influenced small-scale farmers’ side-selling

Evaluation of contextual embeddings on less-resourced languages

The current dominance of deep neural networks in natural language processing is based on contextual embeddings such as ELMo, BERT, and BERT derivatives. Most existing work focuses on English; in contrast, we present here the first multilingual empirical comparison of two ELMo and several monolingual and multilingual BERT models using 14 tasks in nine languages. In monolingual settings, our analysis shows that monolingual BERT models generally dominate, with a few exceptions such as the dependency parsing task, where they are not competitive with ELMo models trained on large corpora. In cross-lingual settings, BERT models trained on only a few languages mostly do best, closely followed by massively multilingual BERT models

Additives for high temperature liquid lubricants. Final report

The purpose of this task was to perform research for the Department of Energy (DOE) on the synthesis and characterization of additives for liquid lubricants which could lead to significant improvements in the major tribological task area of friction and wear reduction at high temperature. To this end JPL surveyed candidate precursor compounds which are soluble in liquid lubricants, synthesized the most promising of these materials, characterized them and submitted these additives to National Institute of Standards and Technology (NIST) for evaluation

Translational Selection Is Ubiquitous in Prokaryotes

Codon usage bias in prokaryotic genomes is largely a consequence of background substitution patterns in DNA, but highly expressed genes may show a preference towards codons that enable more efficient and/or accurate translation. We introduce a novel approach based on supervised machine learning that detects effects of translational selection on genes, while controlling for local variation in nucleotide substitution patterns represented as sequence composition of intergenic DNA. A cornerstone of our method is a Random Forest classifier that outperformed previous distance measure-based approaches, such as the codon adaptation index, in the task of discerning the (highly expressed) ribosomal protein genes by their codon frequencies. Unlike previous reports, we show evidence that translational selection in prokaryotes is practically universal: in 460 of 461 examined microbial genomes, we find that a subset of genes shows a higher codon usage similarity to the ribosomal proteins than would be expected from the local sequence composition. These genes constitute a substantial part of the genome—between 5% and 33%, depending on genome size—while also exhibiting higher experimentally measured mRNA abundances and tending toward codons that match tRNA anticodons by canonical base pairing. Certain gene functional categories are generally enriched with, or depleted of codon-optimized genes, the trends of enrichment/depletion being conserved between Archaea and Bacteria. Prominent exceptions from these trends might indicate genes with alternative physiological roles; we speculate on specific examples related to detoxication of oxygen radicals and ammonia and to possible misannotations of asparaginyl–tRNA synthetases. Since the presence of codon optimizations on genes is a valid proxy for expression levels in fully sequenced genomes, we provide an example of an “adaptome” by highlighting gene functions with expression levels elevated specifically in thermophilic Bacteria and Archaea

Three-dimensional viscous flutter analysis of standard configuration 10

The results of a three-dimensional (3D) viscous flutter analysis for a compressor stage, Standard Configuration 10, are presented. The unsteady flow simulations were performed by a 3D linearized Navier-Stokes flow solver using the Spalart and Allmaras turbulence model. Significant flow blockage due to corner separation at the hub on the suction surface was predicted by the steady-state 3D viscous simulation at a design condition. Corner separation was not predicted by 3D inviscid or two-dimensional (2D) viscous simulations. The corner separation was found to have a destabilizing effect and changed the nature of the unsteady flow. In fact, the 3D viscous simulations predicted negative aerodynamic damping for almost half of the inter-blade phase angles, while the 2D and 3D inviscid simulations predicted stable positive aerodynamic damping for all inter-blade phase angles. An off-design flow condition was also examined and significant differences between the 2D and 3D viscous simulations were found. Copyrigh

Is it all about the money? Extent, reasons and triggers for side-selling in Malawi\u27s paprika supply chain

The purpose of this paper is to advance the knowledge on side-selling. The case study of the paprika supply chain in Central Malawi showed that 36.9% of small-scale farmers engaged in side-selling. It was projected that the focal company lost between 19.9% to 44.6% of paprika due to side-selling. The main reason for side-selling was the higher price offered by local vendors. Binary logit regression indicated that the geographical location, education and income levels, distance to the collection point, a negative impact of contracting on livelihoods, membership in farmers\u27 association and assistance from the Government significantly influenced small-scale farmers’ side-selling

A study of free-piston driven double-diaphragm drivers for expansion tubes

In recent years the free-piston double-diaphragm driver has been used to increase the performance of the XI pilot expansion tube to super-orbital test conditions. However, the actual performance of the double-diaphragm driver was found to be considerably less than ideal. An experimental study of the double-diaphragm driver was carried out on the XI facility over a range of conditions with the objective of determining the effect of: heat losses; and the non-ideal rupture of the ‘light’ secondary diaphragm on the driver performance. The disparity between the theoretical and measured performance envelope are highlighted. A viscous limit for the experiments was established. Heat transfer behind the primary shock is shown to be the mechanism behind this limit. Incident, reflected and transmitted shock trajectories for the secondary diaphragm were experimentally determined and compared with computed trajectories from a one-dimensional diaphragm inertia model. It was found that the diaphragm did influence the unsteady expansion. A good agreement between experimental and computed shock trajectories was obtained using a diaphragm inertia model assuming that the diaphragm mass became negligible 3μ s after shock impact