Investigation of stress fields occurred in the block caving process at a diasporite deposit in Western Turkey

The modeling with the finite element method was employed to study the block caving process for mining the Milas diasporite deposit in Western Turkey. The stress distribution in the vicinity of production and haulage levels is evaluated applying an elasto-plastic rock mass model. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 63–71, November–December, 2005.     

Prevention of insect-borne disease: an approach using transgenic symbiotic bacteria

Expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting insects may serve as a powerful approach to control certain arthropod-borne diseases. The endosymbiont of the Chagas disease vector, Rhodnius prolixus, has been transformed to express cecropin A, a peptide lethal to the parasite, Trypanosoma cruzi. In insects carrying the transformed bacteria, cecropin A expression results in elimination or reduction in number of T. cruzi. A method has been devised to spread the transgenic bacteria to populations of R. prolixus, in a manner that mimics their natural coprophagous route of symbiont acquisition.     

Reconstruction of Hydrometeorological Data in Lake Urmia Basin by Frequency Domain Analysis Using Additive Decomposition

Water Resources Management - Frequency domain analysis using an additive decomposition method is proposed to reconstruct the missing hydrometeorological data of selected sites in Lake Urmia basin...     

Environmental impact of a 290.4 kWp grid-connected photovoltaic system in Kocaeli,Turkey

Clean Technologies and Environmental Policy - This paper examines the environmental impact of a grid-connected PV system in Kocaeli, Turkey, supported by East Marmara Development Agency to...     

Analysis and evaluation of distributed photovoltaic generation in electrical energy production and related regulations of Turkey

Clean Technologies and Environmental Policy - Turkey is a developing country with rising energy demands. Energy access is one of the key parameters to sustain the development, since the country...     

The effect of Nb and heat treatment on the corrosion behavior of ferritic stainless steel in acid environments

The corrosion properties of ferritic stainless steel with admixtures of 0.5, 1.0, and 3.0 wt.% Nb are studied in 0.1M H₂SO₄ and 0.3M HCl solutions. The results obtained by the impedance and mass-loss methods demonstrate that the procedure of alloying with niobium and diffusion treatment positively affect the corrosion resistance of steel in these solutions. Published in Fizyko-Khimichna Mekhanika Materialiv, Vol. 44, No. 4, pp. 89–94, July–August, 2008.     

Laboratory performance comparison of the elastomer-modified asphalt mixtures

In this study, permanent deformation test results on the cylindrical samples produced with the Marshall compaction were compared with the wheel-tracking test results. Three different elastomeric polymer modifiers (OL, EL, and SB) were used. Repeated creep and LCPC wheel-tracking tests were realized at different loading conditions and temperatures. Repeated creep tests at 40 °C temperature do not correlate well with the LCPC wheel-tracking test results at high temperature (60 °C). Performance level of the elastomeric-modified asphalt mixtures can be different for same mixtures at different performance approaches. The evaluation of the dynamic creep test showed that the test can be used as an indicator of potential rutting, but the results in these cases should be confirmed with other more reliable tests. Also it is thought that gradation changing is more effectual than compaction effort types in view of evaluating efficiency of rutting test methods.     

QUAD: Quadrant-based relative location estimates for representative topologies in wireless sensor networks

Sensor networks consist of devices that make various observations in the environment and communicate these observations to a central processing unit from where users can access collected data. In this regard, users’ interpretation of collected data highly depends on the reported location of the sensor making an observation. GPS is an established technology to enable precise location information when deployed in open field. Yet, resource constraints and size issues prohibit its use in small sensor nodes that are designed to be cost-efficient. Instead, locations are estimated using a number of approaches. To date, however, the focus of such estimations was based on individual accuracy of sensor locations in isolation to the complete network. In this paper, we discuss problems with such approaches in terms of data management and analysis. We propose a novel location estimation algorithm called QUAD, quadrant-based localization, to enable representative topology information. In particular, QUAD makes use of relative distances from landmark points to determine the quadrant a node resides in and refines estimations according to neighbour provided information. QUAD makes use of uncertainty levels in estimates to further assist data analysis. Our experiment results suggest significant improvements in individual accuracy prior to optional refinements. Drastic improvements are achieved in the overall topology using refinements.     

Evaluation of synthesized new chitin derivatives in Schottky diode constructions

ABSTRACT

Chitin was reacted with coumarin-3-carboxylic acid (C3CA) and benzophenone-3,3?,4,4?-tetracarboxylic dianhydride (B33?44?TD), and the synthesized chitin derivatives (CC3CA and CB33?44?TD) were characterized by spectroscopic methods and other techniques (FTIR, ¹³C CP/MAS solid-state NMR, XRPD, SEM, and TGA). Also, the charge carrier density, hole mobility, and electrical conductivity of CB33?44?TD were determined. Lastly, Schottky diodes were constructed using these derivatives, and some electrical properties (barrier height, ideality factor, and series resistance) and photoelectrical properties (light sensitivity, short circuit current, and open circuit voltage) of the diodes were determined. It was seen that the diodes have very good ideality factor and light sensitivity.