Trochiscia (Chlorococcales) a new taxon from Central Anatolian Region, Turkey

A new species, Trochiscia anatolicum, is described from a fresh water habitat, Dam Lake in the middle Anatolian region. This new taxon was first found on examination of algal samples from Kesikkopru DamLake. Light microscopes indicate a clear relationship with species in the genus Trochiscia. Some of the characteristic features of the new taxon include a spines and irregular cell wall. And this taxon was under observation for two years

System architecture for road lighting

Traditional road lighting systems consume a large amount of energy. When the ambient light falls under a certain threshold, all the luminaries are turned at full-power without considering user perception and interaction. The feeling of safety experienced by users and user-lighting system interaction via consumer electronics (CE) devices should be investigated. For this study, we establish a software-controlled testbed that allows changing the brightness level of each street luminary remotely. In this paper, we describe the system architecture of this testbed deployed on a street along with the future work directions

Physicochemical, toxicological and ecological analysis of Gökçekaya Dam Lake

Dams built to supply electricity, irrigation and fresh water, change the characteristics of the region they are located. The ecological, limnological characteristics and the quality of water in the dam reservoir deteriorate with time. In this study, the physicochemical, toxicological and ecological parameters of Gökçekaya Dam Lake’s water, which is situated on Sakarya River were examined. The selected area has different characteristics from the others. This lake is situated between two other dam lakes on Sakarya River. So the main water of the lake comes from Sakarya Dam. During the years 2005-2006, water samples were taken from the lake surface and depths in seasonal periods, and the physical, chemical and biological parameters were examined to determine the modifications in the quality of water. It was seen that while the quality had no certain differences, the level of the nutrients in the water was low. The different characteristics of the coming water enriched the varieties of algae. It was concluded thatthe structure of the water in Gökçekaya Dam Lake is mezotrophic

The accumulation of heavy metals (Cd, Pb, Hg, Cr) and their state in phytoplanktonic algae and zooplanktonic organisms in Beysehir Lake and Mogan Lake, Turkey

Beysehir and Mogan Lakes are two shallow Lakes that are under environmental protection status. Phytoplanktonic dominant algae determined in Beysehir Lake were Oscillatoria sp., Cladophora sp.,Achnanthes sp., Gomphonema sp., Navicula sp., Cosmarium sp., Cymbella sp., Fragilaria sp., Oocystis sp., Spirogyra sp., Diatomae sp., Microcystis sp. and Staurastrum sp. While in Mogan Lake, Spirogyra sp., Zygnema sp., Euglena sp., Achnanthes sp., Cymbella sp., Fragilaria sp. Navicula sp., Scenedesmus sp., Oocystis sp., Synedra sp., Oscillatoria sp., Chlorella sp., Cosmarium sp. and Nitzshia sp. were determined. Zooplanktonic dominant organisms determined in Beysehir Lake were Eudiaptomus drieshi, Daphnia longispina and Brachionus calyciforus while Arctodiaptomus sp., Keratella quadrata, Filinia longiseta and Diaphanosoma lacustris were determined in Mogan Lake. Accumulation of heavy metals (Cd, Pb, Hg and Cr) in the water and plankton of Beysehir and Mogan Lakes was studiedseasonally, from April 2000 to December 2004. Higher concentration with all heavy metals was recorded in plankton. Mercury (Hg) was found in lowest and lead (Pb) in the highest correlation; however, the concentration of each metal varied seasonally. In addition, the seasonal changes inphytoplankton and zooplankton populations and species abundance were also determined. Some physical-chemical parameters of water and their correlation with heavy metals were also examined

Transversality Conditions for Infinite Horizon Variational Problems on Time Scales

We consider problems of the calculus of variations on unbounded time scales. We prove the validity of the Euler-Lagrange equation on time scales for infinite horizon problems, and a new transversality condition.Comment: Submitted 6-October-2009; Accepted 19-March-2010 in revised form; for publication in "Optimization Letters"

Direct and Inverse Variational Problems on Time Scales: A Survey

We deal with direct and inverse problems of the calculus of variations on arbitrary time scales. Firstly, using the Euler-Lagrange equation and the strengthened Legendre condition, we give a general form for a variational functional to attain a local minimum at a given point of the vector space. Furthermore, we provide a necessary condition for a dynamic integro-differential equation to be an Euler-Lagrange equation (Helmholtz's problem of the calculus of variations on time scales). New and interesting results for the discrete and quantum settings are obtained as particular cases. Finally, we consider very general problems of the calculus of variations given by the composition of a certain scalar function with delta and nabla integrals of a vector valued field.Comment: This is a preprint of a paper whose final and definite form will be published in the Springer Volume 'Modeling, Dynamics, Optimization and Bioeconomics II', Edited by A. A. Pinto and D. Zilberman (Eds.), Springer Proceedings in Mathematics & Statistics. Submitted 03/Sept/2014; Accepted, after a revision, 19/Jan/201

Euler-Lagrange equations for composition functionals in calculus of variations on time scales

In this paper we consider the problem of the calculus of variations for a functional which is the composition of a certain scalar function $H$ with the delta integral of a vector valued field $f$, i.e., of the form $H(\int_{a}^{b}f(t,x^{\sigma}(t),x^{\Delta}(t))\Delta t)$. Euler-Lagrange equations, natural boundary conditions for such problems as well as a necessary optimality condition for isoperimetric problems, on a general time scale, are given. A number of corollaries are obtained, and several examples illustrating the new results are discussed in detail.Comment: Submitted 10-May-2009 to Discrete and Continuous Dynamical Systems (DCDS-B); revised 10-March-2010; accepted 04-July-201

The Hahn Quantum Variational Calculus

We introduce the Hahn quantum variational calculus. Necessary and sufficient optimality conditions for the basic, isoperimetric, and Hahn quantum Lagrange problems, are studied. We also show the validity of Leitmann's direct method for the Hahn quantum variational calculus, and give explicit solutions to some concrete problems. To illustrate the results, we provide several examples and discuss a quantum version of the well known Ramsey model of economics.Comment: Submitted: 3/March/2010; 4th revision: 9/June/2010; accepted: 18/June/2010; for publication in Journal of Optimization Theory and Application