Design, fabrication, and test of a composite material wind turbine rotor blade

The aerodynamic design, structural design, fabrication, and structural testing is described for a 60 foot long filament wound, fiberglass/epoxy resin matrix wind turbine rotor blade for a 125 foot diameter, 100 kW wind energy conversion system. One blade was fabricated which met all aerodynamic shape requirements and was structurally capable of operating under all specified design conditions. The feasibility of filament winding large rotor blades was demonstrated

Aerosol–Cloud Interaction: A Case Study

MODerate Resolution Imaging Spectroradiometer (MODIS) retrieved aerosol and cloud products at the nine selected stations over Western Himalayan and Deccan Plateau regions were inferred to bring out their salient features and to investigate aerosol–cloud interaction. Annually, Ångström exponent (AE) decreases with aerosol optical depth (AOD) while in winter it increases with AOD at most of the stations. Results bring out positive and/or negative association between AOD and almost all the cloud parameters over the selected stations. Aerosol indirect effect (AIE) is quantified for fixed liquid water path (LWP) bins ranging from 1 to 350 g/m2 at an interval of 25 g/m2 for three categories of stations, viz., CAT‐H, CAT‐M, and CAT‐L based on heavy, moderate, and low aerosol loading, respectively. AIE is negative at CAT‐H (−0.04 ± 0.14), while it is positive at CAT‐M (0.01 ± 0.07) and CAT‐L (0.10 ± 0.48). During winter, negative AIE has been observed for all three categories. In pre‐monsoon, the majority of LWP bins (86% at CAT‐H and 60% at CAT‐M) showed positive AIE, while about 71% of LWP bins indicted negative AIE at CAT‐L. However, during monsoon about 63–71% of LWP bins showed negative AIE at these categories. Study elucidates the influence of factors like cloud type, cloud dynamics/thermodynamics on aerosol–cloud interactions

Dark matter-baryons separation at the lowest mass scale: the Bullet Group

We report on the X-ray observation of a strong lensing selected group, SL2S J08544-0121, with a total mass of $2.4 \pm 0.6 \times 10^{14}$ $\rm{M_\odot}$ which revealed a separation of $124\pm20$ kpc between the X-ray emitting collisional gas and the collisionless galaxies and dark matter (DM), traced by strong lensing. This source allows to put an order of magnitude estimate to the upper limit to the interaction cross section of DM of 10 cm$^2$ g$^{-1}$. It is the lowest mass object found to date showing a DM-baryons separation and it reveals that the detection of bullet-like objects is not rare and confined to mergers of massive objects opening the possibility of a statistical detection of DM-baryons separation with future surveys.Comment: 5 pages, 3 figures. Accepted for publication in MNRAS Letters. Typos correcte

Nucleus-Electron Model for States Changing from a Liquid Metal to a Plasma and the Saha Equation

We extend the quantal hypernetted-chain (QHNC) method, which has been proved to yield accurate results for liquid metals, to treat a partially ionized plasma. In a plasma, the electrons change from a quantum to a classical fluid gradually with increasing temperature; the QHNC method applied to the electron gas is in fact able to provide the electron-electron correlation at arbitrary temperature. As an illustrating example of this approach, we investigate how liquid rubidium becomes a plasma by increasing the temperature from 0 to 30 eV at a fixed normal ion-density $1.03 \times 10^{22}/cm^3$. The electron-ion radial distribution function (RDF) in liquid Rb has distinct inner-core and outer-core parts. Even at a temperature of 1 eV, this clear distinction remains as a characteristic of a liquid metal. At a temperature of 3 eV, this distinction disappears, and rubidium becomes a plasma with the ionization 1.21. The temperature variations of bound levels in each ion and the average ionization are calculated in Rb plasmas at the same time. Using the density-functional theory, we also derive the Saha equation applicable even to a high-density plasma at low temperatures. The QHNC method provides a procedure to solve this Saha equation with ease by using a recursive formula; the charge population of differently ionized species are obtained in Rb plasmas at several temperatures. In this way, it is shown that, with the atomic number as the only input, the QHNC method produces the average ionization, the electron-ion and ion-ion RDF's, and the charge population which are consistent with the atomic structure of each ion for a partially ionized plasma.Comment: 28 pages(TeX) and 11 figures (PS

Logarithmic corrections to black hole and black ring entropy in tunneling approach

The tunneling approach beyond semiclassical approximation has been used to calculate the corrected Hawking temperature and entropy for various black holes and FRW universe model. We examine their derivations, and prove that the quantity $H$ in the corrected temperature is the explicit function of the only free parameter $\mathcal{A}$ (which is an auxiliary parameter defined by $\mathcal{A}=\hbar S_{BH}$). Our analysis improves previous calculations, and indicates that the leading order logarithmic correction to entropy is a natural result of the corrected temperature and the first law of thermodynamics. Additionally, we apply the tunneling approach beyond semiclassical approximation to neutral black rings. Based on the analysis, we show that the entropy of neutral black rings also has a logarithmic leading order correction.Comment: 13 pages, rewritte

Addressing resource over-exploitation via cooperative institutions: Examining how technology roadmapping could contribute

Just one of the challenges facing the manufacturing sector is to dramatically improve non-labour based resource productivity as the world enters a period of sustained resource scarcity. The traditional linear consumption model of extraction to waste has led to the unsustainable consumption of finite resources, and as manufacturing output grows in line with global population, the price of resources is only expected to rise in the future. In order for resource use in the manufacturing sector to be sustainable, consumption of renewable resources must brought into line with their rate of regeneration, and non-renewables resources must be recycled within a circular economy. In a resource constrained world, resources will shift from being seen as cheap commodities to be consumed to valuable resources to be maintained as part of a global commons. Elinor Ostrom’s research into this subject of common-pool resources set out design principles for successful institutions which protected against their over-exploitation. One of the fundamental success factors in these small forest and fishing communities was collaboration, individuals coordinating their efforts to self-regulate and manage to ensure resources are not over-exploited. However in a globalised world, where long and complex supply chains reduce awareness of a firm’s indirect resource uses, there is a danger that through ignorance global common resources are being over-exploited. Manufacturing supply chains are the epitome for complex supply chains, and these firms rely on many man made and natural resources, and thus are dependent on sustainable resource management to ensure their long term survival. This paper examines the potential for roadmapping to foster collaboration between firms in an industry to create cooperative institutions such as those examined by Ostrom.This is the accepted manuscript. The final version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S221282711400921

Intra-oral Effects on Acid-softened Enamel of NaF Lozenges Administered in Divided Daily Doses

The purpose of this investigation was to study the intra-oral effects of multiple daily applications of NaF lozenges upon acid-softened enamel. Bovine enamel slabs were softened with 0.1 mol/L lactate buffer at pH 4.0 for 14 hrs and subsequently mounted in a mandibular removable Hawley appliance. Control slabs were worn for seven days by eight adult male subjects who brushed their natural dentition daily with a fluoride-free dentifrice. Test slabs were exposed to one 0.55-mg NaF lozenge (0.25 mg F) 4x/day for seven days and the natural dentition brushed with a fluoride-free dentifrice. The efficacy of 0.25-mg F lozenges used 4x/day over that of a 1-mg F lozenge administered 1x/day was established by a pilot study with two subjects. Microhardness testing was performed after intra-oral exposure (IOE) and following immersion in 0.01 mol/L lactate buffer containing Ca and P04 for 24 hrs at a pH of 4.0. Fluoride uptake was measured on separate control and test slabs after KOH wash and after acid-resistance-testing (ART). Recovery of microhardness following IOE was 40.9% for controls and 53.9% for treated slabs, while control slabs retained 1.3% resistance to ART, compared with 25.6% for test slabs. The F content of the control slabs was significantly less than that of lozenge-treated and lozenge-treated-ART slabs throughout the depth of the lesion. The F content of the lozenge-treated-ART slabs was significantly less than that of the lozenge-treated slabs only at the 0-5-μm depth. The NaF lozenge-treated enamel lesions demonstrated both significantly greater rehardening and F uptake than did the untreated control enamel lesions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67350/2/10.1177_00220345870660050501.pd

First impressions and perceived roles: Palestinian perceptions on foreign aid

This paper summarizes some results of a wider research on foreign aid that was conducted in the West Bank and Gaza Strip in 2010. It seeks to describe the impressions and feelings of Palestinian aid beneficiaries as well as the roles and functions they attached to foreign aid. To capture and measure local perceptions on Western assistance a series of individual in depth interviews and few focus group interviews were conducted in the Palestinian territories. The interview transcripts were processed by content analysis. As research results show — from the perspective of aid beneficiaries — foreign aid is more related to human dignity than to any economic development. All this implies that frustration with the ongoing Israeli-Palestinian conflict inevitably embraces the donor policies and practices too