Comments on "New hypergeometric identities arising from Gauss’s second summation theorem"

In 1997, Exton [J. Comput. Appl. Math. 88 (1997) 269–274] obtained a general transfor- mation involving hypergeometric functions by elementary manipulation of series. A number of hypergeometric identities not previously recorded in the literature were then deduced by application of Gauss’ second summation theorem and other known hypergeometric summa- tion theorems. However, many of the results stated by Exton contain errors. It is the purpose of this note to present the corrected forms of these hypergeometric identities

Magnetoresistance of atomic-sized contacts: an ab-initio study

The magnetoresistance (MR) effect in metallic atomic-sized contacts is studied theoretically by means of first-principle electronic structure calculations. We consider three-atom chains formed from Co, Cu, Si, and Al atoms suspended between semi-infinite Co leads. We employ the screened Korringa-Kohn-Rostoker Green's function method for the electronic structure calculation and evaluate the conductance in the ballistic limit using the Landauer approach. The conductance through the constrictions reflects the spin-splitting of the Co bands and causes high MR ratios, up to 50%. The influence of the structural changes on the conductance is studied by considering different geometrical arrangements of atoms forming the chains. Our results show that the conductance through s-like states is robust against geometrical changes, whereas the transmission is strongly influenced by the atomic arrangement if p or d states contribute to the current.Comment: Revised version, presentation of results is improved, figure 2 is splitted to two figure

A review of Fixed Bed Gasification Systems for Biomass

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): A review of Fixed Bed Gasification Systems for Biomass. Invited Overview. Vol. IX. April, 2007

Thermal design improvements for 30kWe arcjet engine

Two thermal design improvements for 30 kWe arcjet engines are described. A ZrB2 high temperature coating was used to increase the surface emissivity of the nozzle radiating surface, enabling lower temperature operation, which should lead to longer nozzle life. The ZrB2-coated engine operated 120 C cooler than the uncoated baseline engine indicating a 30 percent increase in the surface emissivity. An engine design which has fewer active seals than previous designs and operates at lower overall component temperatures is described. The nozzle on the engine operated at 1950 C at 30 kWe while the baseline engine nozzle reached 2000 C at 23 kWe. The back of the engine was more than a factor of two cooler when compared to the baseline engine

Evaluation of ground water quality near Chandi Devi bridge solid waste dumping site at Hairdwar city, (Uttarakhand), India : A case study

The present study observed groundwater quality around Chandi Devi bridge open dumping site at Hardwar (Uttarakhand), India. Five experimental sites viz. sites 2,3 and 5 (hand pumps) and  two sites 4,6  (tubewells) within the vicinity of the dumpsite and a reference site viz. site 1 (hand pump) (Bilkeshwar temple) as a control about 5000 meter away, were selected to ascertain the influence of solid waste dumping on groundwater quality around the area. The study showed that physicochemical parameters viz temperature, colour, turbidity, pH, hardness, BOD, COD, fluoride  and heavy metals ( lead and iron) of the ground water near the dumping sites-2,3,4,5,6 were higher than their counterpart parameters of the ground water at control site. However, arsenic was not detected in any sample of all the sites. The parameters viz., colour (2.08-3.49 hazen), turbidity (3.05-5.35 NTU), odour (agreeable), pH (7.46-7.80),fluoride (0.10-0.38 ppm), lead (0.00-0.032 ppm), iron (0.01-0.03 ppm) of ground water of all experimental sites were within permissible limits while the parameters BOD (3.73-3.21 ppm), hardness (240.41-203.15 ppm) at site-2, site-3 and DO (5.38-6.28 ppm) of all experimental sites were not found within permissible limits  as prescribed by Bureau  of Indian standards (2012). Although water was safe for drinking which may be due to higher infiltration rate of river Ganga and Eastern Ganga Canal water but higher value of temperature (oC), colour (hazen), turbidity (ppm), hardness (ppm), BOD (ppm), COD (ppm) fluoride (ppm), iron (ppm) and lead (ppm) at site- 2 was quite alarming. The study would help in making public awareness for waste sorting, adopting green technology and to predict level of contaminants in ground water produced by land filling dumping site

From social machines to social protocols:Software engineering foundations for sociotechnical systems

The overarching vision of social machines is to facilitate social processes by having computers provide administrative support. We conceive of a social machine as a sociotechnical system (STS): a software-supported system in which autonomous principals such as humans and organizations interact to exchange information and services. Existing approaches for social machines emphasize the technical aspects and inadequately support the meanings of social processes, leaving them informally realized in human interactions. We posit that a fundamental rethinking is needed to incorporate accountability, essential for addressing the openness of the Web and the autonomy of its principals. We introduce Interaction-Oriented Software Engineering (IOSE) as a paradigm expressly suited to capturing the social basis of STSs. Motivated by promoting openness and autonomy, IOSE focuses not on implementation but on social protocols, specifying how social relationships, characterizing the accountability of the concerned parties, progress as they interact. Motivated by providing computational support, IOSE adopts the accountability representation to capture the meaning of a social machine’s states and transitions. We demonstrate IOSE via examples drawn from healthcare. We reinterpret the classical software engineering (SE) principles for the STS setting and show how IOSE is better suited than traditional software engineering for supporting social processes. The contribution of this paper is a new paradigm for STSs, evaluated via conceptual analysis

Impact of climate change on biodiversity of India with special reference to Himalayan region-An overview

India possesses a distinct identity, not only because of its geography, history and culture, but also because of the great diversity of its natural ecosystems. The panorama of Indian biological diversity is much wider, as it comes under the twelve mega biodiverse (Hot-spot) centers of the world. It contains a great wealth of biological diversity in its forests, its wetlands and in its marine areas which are distributed all over the country. This richness is shown in absolute numbers of species and the proportion they represent of the world total. The great Himalayan region has peculiar identity in the perspective of its unique biogeography. It supports a large number of glaciers, lakes, rivers, flora and fauna due to its variable climate. It has a profound effect on the climate of the subcontinent. But due to anthropogenic activities the global climate has changed since last few decades. The climate of the subcontinent has also adversely affected the biological resources of the country along with that of the Himalayan region. The present paper discusses the various causes responsible for melting and shrinkage of glaciers, decreasing water flow in the major rivers, increasing pressure of extinction of the ecological wealth of the country. It also talks about the control measures and various management steps which can be taken, with special reference to the Himalayan region

Influence of sugar mill effluent on physico-chemical characteristics of soil at Haridwar (Uttarakhand), India

The influence of seven rates of Sugar mill effluent (viz. 0, 5, 10 25, 50, 75 and 100 ml/kg soil) along with control (Bore-well water, BWW) on the physical and chemical properties of soils revealed that among various concentrations of the effluents, the irrigation with 100% effluent concentration decreased moisture content (20.44%),WHC (13.80%), BD (4.14%) and increased pH (9.56%), EC (64.28%), ECEC (149.25%), Cl- (194.71%), OC (3228.89%), HCO3- (22.34%), CO3-2 (29.38%), Na + (185.48%), K+(53.40%), Ca2+ (1262.24%), Mg2+ (1818.24%), TKN (1206.36%), NO32- (80.87%), PO43- (236.04%), SO42- (72.08%), Fe2+ (234.34%), Zn (317.72%), Cd (404.35%), Cu (374.90%), Pb (645.71%) and Cr (1024.80%) in the soil when compared to control. There was a significant (P<0.001) effect on EC, pH, Cl-, OC, HCO3- , CO32- , Na + , K + , Ca2+, Mg 2+, Fe 2+, TKN, NO3 2- , PO4 3- and SO42- , Zn, Cu, Cd, Cr and Pb and insignificant (P>0.05) effect on moisture content, WHC and bulk density after sugar mill effluent irrigation when compared to control. There was no momentous change in the soil texture of the soil. The enrichment factor (Ef) of various micronutrients in the soil was recorded in order of Cr>Pb>Cd>Cu>Zn after irrigation with sugar mill effluent