Solar cell angular position transducer

An angular position transducer utilizing photocells and a light source is disclosed. The device uses a fully rotatable baffle which is connected via an actuator shaft to the body whose rotational displacement is to be measured. The baffle blocks the light path between the light source and the photocells so that a constant semicircular beam of light reaches the photocells. The current produced by the photocells is fed through a resistor, a differential amplifier measures the voltage drop across the resistor which indicates the angular position of the actuator shaft and hence of the object

Prevention of arthritis by interleukin 10-producing B cells

In this study we have shown that activation of arthritogenic splenocytes with antigen and agonistic anti-CD40 gives raise to a B cell population that produce high levels of interleukin (IL)-10 and low levels of interferon (IFN)-{gamma}. Transfer of these B cells into DBA/1-TcR-ß-Tg mice, immunized with bovine collagen (CII) emulsified in complete Freund's adjuvant inhibited T helper type 1 differentiation, prevented arthritis development, and was also effective in ameliorating established disease. IL-10 is essential for the regulatory function of this subset of B cells, as the B cells population isolated from IL-10 knockout mice failed to mediate this protective function. Furthermore, B cells isolated from arthritogenic splenocytes treated in vitro with anti–IL-10/anti–IL-10R were unable to protect recipient mice from developing arthritis. Our results suggest a new role of a subset of B cells in controlling T cell differentiation and autoimmune disorders

Early Results on Radioactive Background Characterization for Sanford Laboratory and DUSEL Experiments

Measuring external sources of background for a deep underground laboratory at the Homestake Mine is an important step for the planned low-background experiments. The naturally occurring $\gamma$-ray fluxes at different levels in the Homestake Mine are studied using NaI detectors and Monte Carlo simulations. A simple algorithm is developed to convert the measured $\gamma$-ray rates into $\gamma$-ray fluxes. A good agreement between the measured and simulated $\gamma$-ray fluxes is achieved with the knowledge of the chemical composition and radioactivity levels in the rock. The neutron fluxes and $\gamma$-ray fluxes are predicted by Monte Carlo simulations for different levels including inaccessible levels that are under construction for the planned low background experiments.Comment: 16 pages, 2 figures, and 9 table

A study of physical and hydraulic properties of green roof substrates including waste materials

Green roofs are becoming increasingly popular in the urban landscape, where levels of air pollution from numerous sources of emissions have rapidly risen compared to rural areas. Green roofs are designed to retain precipitated water, while filtering out pollutants, provide insulation, reduce roof construction costs, be lightweight, contribute to the reduction of temperatures in cities and create habitats for wildlife. When designing green roofs, substrate composition is an important consideration for water retention, plant growth and water quality of runoff. To increase further the sustainability of the green roof systems in terms of material usage, waste materials could be introduced to replace natural soils in the sustrate layer. Current standards however do not include such materials, which appears to be a missed opportunity. In this context, this paper focuses on a number of typical materials used in the green roof substrates and potential suitable alternatives to these, coming from waste streams. For the mixes, commercial growing medium/substrate (control mix) and some common natural or manufactured materials were used, trying to create appropriate substrate mixes in terms of physical and hydraulic properties. These materials were then replaced by waste materials of similar characteristics (e.g., crushed clay brick, paper sludge, and waste glass cullet aggregate, to replace respectively LECA expanded clay, peat and fines such as clay size particles, and sand). For nutrient retention, some small proportion of zeolite was also used in some of the mixes. To assess the suitability of the different mixes with waste materials as extensive green roof substrates, in comparison with commonly used substrate materials, a number of physical hydraulic property tests were performed, as well as germination tests, to attest whether the mixes with the waste materials were adequate for plant growth. The results showed that the studied mixes of different components were overall suitable as green roof substrates and supported plant growth. This encourages further research on the topic (including environmental safety testing, and microbial community studies) towards potential future inclusion of such mixes in green roof design standards

Fire extinguishing apparatus having a slidable mass for a penetrator nozzle

A fire extinguishing apparatus for delivering an extinguishing agent through a tarrier surrounding a structure into its interior includes an elongated tubular nozzle body which has a pointed penetrating head carried on one end of the tubular body. A source of extinguishing agent coupled to the opposite end of the tubular body is fed through and passes through passages adjacent the head for delivering the extinguishing agent to the interior of the structure. A slidable mass is carried on the tubular body on a remote end of the tubular body from the penetrating head. By manipulating the slidable mass and bringing such in contact with an abutment the force imparted to the tubular body causes the head to penetrate the structure

The Limits of Discipline: Ownership and Hard Budget Constraints in the Transition Economies

This paper argues that the imposition of financial discipline is not sufficient to remedy ownership and governance-related deficiencies of corporate performance. Using evidence from the postcommunist transition economies, the paper shows that a policy of hard budget constraints falters when state firms, because of inferior revenue performance and lesser willingness to meet payment obligations, continue to pose higher credit risk than privatized firms. The brunt of state firms' lower creditworthiness falls on state creditors. But the "softness" of these creditors is unavoidable if it prevents a demise of firms that are in principle capable of successful restructuring through ownership changes.OWNERSHIP; FINANCIAL DISCIPLINE; PERFORMANCE; TRANSITION.

Development and demonstration of a flutter-suppression system using active controls

The application of active control technology to suppress flutter was demonstrated successfully in the transonic dynamics tunnel with a delta-wing model. The model was a simplified version of a proposed supersonic transport wing design. An active flutter suppression method based on an aerodynamic energy criterion was verified by using three different control laws. The first two control laws utilized both leading-edge and trailing-edge active control surfaces, whereas the third control law required only a single trailing-edge active control surface. At a Mach number of 0.9 the experimental results demonstrated increases in the flutter dynamic pressure from 12.5 percent to 30 percent with active controls. Analytical methods were developed to predict both open-loop and closed-loop stability, and the results agreed reasonably well with the experimental results

AdS Strings with Torsion: Non-complex Heterotic Compactifications

Combining the effects of fluxes and gaugino condensation in heterotic supergravity, we use a ten-dimensional approach to find a new class of four-dimensional supersymmetric AdS compactifications on almost-Hermitian manifolds of SU(3) structure. Computation of the torsion allows a classification of the internal geometry, which for a particular combination of fluxes and condensate, is nearly Kahler. We argue that all moduli are fixed, and we show that the Kahler potential and superpotential proposed in the literature yield the correct AdS radius. In the nearly Kahler case, we are able to solve the H Bianchi using a nonstandard embedding. Finally, we point out subtleties in deriving the effective superpotential and understanding the heterotic supergravity in the presence of a gaugino condensate.Comment: 42 pages; v2. added refs, revised discussion of Bianchi for N

Unified molecular field theory of nematic, smectic-A, and smectic-C phases

A unified mean-field molecular theory of nematic (NU), smectic A (SmA), and smectic C (SmC) liquid crystal phases, composed of uniaxial nonpolar molecules, is developed taking into account the variation of all orientational and translational order parameters in these phases. Numerical results, obtained by direct global minimization of the free energy, are presented in the form of three typical phase diagrams of different topology. Temperature variation of the relevant order parameters in different sequences of phases is analyzed for various cross sections of the phase diagrams. The present model enables one to reproduce all possible sequences of phase transitions between the given phases including isotropic (Iso)-NU-SmA-SmC, Iso-NU-SmC, Iso-SmA-SmC, and Iso-SmC. The properties of the NAC point, where the NU, SmA, and SmC structures coexist, are considered in detail and the shape of the phase diagram in the vicinity of the NAC point is compared with existing experimental data

A Study of Innovative Alkali-Activated Binders for Soil Stabilisation in the Context of Engineering Sustainability and Circular Economy

In the context of sustainability in the civil engineering industry, chemical ground improvement is becoming increasingly used, as a generally more sustainable alternative to replacing and landfilling unsuitable for construction ground. However, traditional soil stabilisers such as Portland cement or lime are not environmentally impact-free; international research effort is thus focusing on the development of innovative cementing agents. This paper presents results from a feasibility study on the development of suitable alkali-activated slag cements for the stabilisation of two soils. A number of alkali-activators were considered, comprising potassium hydroxide, a range of alkali salts, as well as a material retrieved from waste (Paper Sludge Ash, PSA) which contains free lime. Indicative results of an extensive parametric study in terms of unconfined compressive strength (UCS) are shown, followed by results of ongoing oedometer tests to determine soil compressibility and some preliminary tests on selected soil/binder mixes to observe the durability to wetting-drying cycles. Overall, all alkali-activated cement mixes increased the UCS and stiffness of the soil. Carbonates and Na 2 SiO 3 used on their own gave lower strength increases. The highest strengths were achieved from AAC with KOH and Ca(OH) 2 from PSA, which showed similar strength gain. The latter material has shown consistently a lot of promise in terms of strength, stiffness and volumetric stability of the soil as well as treatment durability. Ongoing research focuses on further mix optimisation and a comprehensive mechanical and durability property testing supported by material analysis (mineralogical, chemical and microstructural) to gain a better understanding of the complex mechanisms involved