Characteristics of traditionally processed shea kernels and butter

The traditional production of shea butter requires a heat treatment of the nuts. This study compared the end products derived by two commonly used heat treatments, namely smoking and boiling followed by sun‐drying. Neither treatment influenced the moisture content of the kernels (8–10%), but the boiling treatment resulted in more free fatty acids (FFA) (6%) and a higher fat content (41%) of kernels. A sensory panel preferred shea butter from boiled kernels because of its soft texture and intense smell. This butter also had the highest values for moisture content (2%), unsaponifiable matter (7%), tocopherol compounds (125 mg g^?1), peroxide value (8 meq O₂ kg^?1), iodine value (53 mg I₂ 100 g^?1) and FFA (2%). Minor variations were noticed in the fatty acid profile. Aside from the use of butter from both boiled and smoked kernels in cosmetics, the butter from smoked kernels will be more suitable for food purposes.     

A Water Surface Wave-Height Radio Telemeter

ABSTRACT

This paper discusses the evolution of a telemetric device that enables the remote measurement of surface wave height on a freshwater lake. The basic instrumentation package uses an anchored, insulated metal probe as a capacitive sensor element to determine peak wave amplitudes up to 1 m; the probe also serves as the mechanical support for a lightweight UHF radio-link antenna. The principal system design considerations and circuit details of the baseband signal processing stages are included; representative test results are documented.     

Laser chemical vapor deposition of TiC on tantalum

Laser chemical vapor deposition (LCVD) of titanium carbide (TiC) coatings onto tantalum substrates using hydrogen gas, titanium tetrachloride (TiCl₄) and either methane (CH₄) or acetylene (C₂H₂) source gasses was investigated. The influences of the molar ratio of the source gases and the deposition temperature on the phase assemblage, composition, and morphology of the coatings was examined. Using C₂H₂, nearly stoichiometric coatings were produced at 1000°C and at a TiCl₄/C₂H₂ ratio of 1/0.4. Stoichiometric coatings were also produced using CH₄ but the deposition temperature was 400°C higher and a much larger fraction of the carbon source was required compared to C₂H₂. Although deposition rates were much slower when using CH₄, the coatings exhibited a smoother surface finish and had a higher density compared to those produced using C₂H₂. The suitability of CH₄ and C₂H₂ as carbon sources for depositing stoichiometric, phase-pure coatings is discussed in light of these results.     

Artificial intelligence and natural magic

Robotics with AI is part of a long tradition that has run from ancient times that treated the precursors of robots, the automata, as part of Natural Magic or conjury. Deception is an integral part of AI and robotics; in some ways they form a science of illusion. There are many robot tasks, such as caring for the elderly, minding children, doing domestic chores and being companionable, that involve working closely with humans and so require some illusion of animacy and thought. We discuss how the natural magic of robotics is assisted by the cultural myth of AI together with innate human predispositions such as zoomorphism, the willing suspension of disbelief and a tendency to interpret AI devices as part of the social world. This approach provides a justifiable way of meeting the goals of AI and robotics provided that researchers do not allow themselves to be deceived by their own illusions.     

Technology adoption as process: a case of integrating an information-intensive website into a patient education helpline

This study followed the introduction of the Arthritis Source website into the existing teaching practices of Arthritis Foundation Helpline volunteers. The goal was to examine what factors may affect a particular group of educators adopt a potentially valuable Internet tool into an existing instructional environment. Defining the possible uses of the website in reference to the volunteers' actual job duties helped provide a clearer understanding of how the volunteers might use this new technology. The researchers used qualitative techniques to focus on three volunteers who experienced different physical, environmental and cognitive means that impacted their use of the new tool. Each volunteer experienced varying levels of motivation in areas of learning, satisfaction and responses to outside influences. Each volunteer also had varying amounts of opportunity prompts in which to interact or refer the website. Consequently, Helpline volunteers experienced different rates of adopting the information-intensive website into their traditional work system.     

Participatory landscape analysis to guide restoration of ponderosa pine ecosystems in the American Southwest

Over the past 5 decades, stand-replacing crown fires have increased in size and frequency throughout the long-needled pine forests of the American Southwest. Suppression of frequent, low-intensity ground fires has resulted in dense stands of fire-prone trees over large areas. Efforts to restore forest structure to conditions that would permit a return to historical fire regimes, characterized by frequent ground fire, are hindered by the inability of managers and the public to compare the effects of alternative forest management practices on fire behavior and a host of other issues. Currently, forest management is mired in controversy, endangering ecosystem function, biodiversity, public safety, and municipal watersheds. Our research program, motivated by the need to examine cumulative effects of many independent management decisions over large planning areas, focuses on the development of spatial data and modeling tools that enable diverse stakeholders to work together to guide landscape-scale planning efforts. Data layers describing forest composition and structure facilitate modeling of fire threat and wildlife habitat over areas of several hundred thousand hectares. Modeling alternative forest management scenarios via a collaborative, public process fosters informed discourse and helps conflicting parties forge appropriate policy and identify management responses that meet restoration objectives.     

Selective doping of silicon by rapid thermal and laser assisted processes

The selective doping technique, made by the combination of spin-on dopant (SOD) source deposition, rapid thermal annealing (RTA) and laser treatments is proposed as an innovative process for large area devices, like silicon solar cells.Rapid thermal diffusion (RTD) is first carried out from phosphorus SOD layers to form a lightly doped junction followed by pulsed laser irradiation to induce overdoping in selectively chosen regions.Here we present extensive study on the dependence of selective doping efficiency through different working variables, such as dopant source dilution, diffusion temperature and time for RTPs, and power and translation velocity for lasers. Electrical and structural characterizations have been performed by using several techniques: SIMS, stripping-Hall, four-point probe resistivity, SEM and TEM analysis.The combined use of these processes has been applied to the realization of selective emitter structures for silicon solar cells.     

Estimation of model quality

This paper provides an introduction to recent work on the problem of quantifying errors in the estimation of models for dynamic systems. This is a very large field. We therefore concentrate on approaches that have been motivated by the need for reliable models for control system design. This will involve a discussion of efforts that go under the titles of ‘estimation in ’, ‘worst-case estimation’, ‘estimation in ℓ₁’ and ‘stochastic embedding of undermodelling’. A central theme of this survey is to examine these new methods with reference to the classic bias/variance tradeoff in model structure selection.     

Kinetics of decarburisation of levitating liquid iron drops by carbon dioxide

Decarburisation experiments were carried out by levitating liquid iron droplets in a flowing gas stream containing carbon dioxide at 1723K. Decarburisation of liquid iron droplets by carbon dioxide can be adequately described by the mixed control of gas phase mass transport and dissociative chemisorption of carbon dioxide. Carbon monoxide in the gas phase does not have any significant effect on the rate of decarburisation. The rate of decarburisation decreases significantly with increase in sulphur content in the melt and this effect can be quantitatively explained using the Langmuir isotherm. Adsorption coefficient of sulphur is found to be 200. Influence of phosphorus and chromium in the melt on the rate of decarburisation is negligibly small.