Determining the effective constitutive parameters of finite periodic structures: photonic crystals and metamaterials

Cataloged from PDF version of article.A novel approach to find the effective electric and A novel approach to find the effective electric and magnetic parameters of finite periodic structures is proposed. The method uses the reflection coefficients at the interface between a homogenous half-space and the periodic structure of different thicknesses. The reflection data are then approximated by complex exponentials, from which one can deduce the wavenumber, and the effective electric and magnetic properties of the equivalent structure by a simple comparison to the geometrical series representation of the generalized reflection from a homogenous slab. Since the effective parameters are for the homogenous equivalent of the periodic structure, the results obtained are expected to be independent of the number of unit cells used in the longitudinal direction. Although the proposed method is quite versatile and applicable to any finite periodic structure, photonic crystals and metamaterials with metallic inclusions have been used to demonstrate the application of the method in this paper. © 2008 IEEE

Determination of heavy metal content in commercial marine fish hunted from southeast Aegean Sea (Turkey) and their potential risk for public health

In this study, heavy metals such as Al, Cr, Cu, Zn, Cd, Hg, Pb etc. content in liver, muscle and gill of three economical marine species [striped seabream (Lithognathus mormyrus Linneaus, 1758), two-band bream (Diplodus vulgaris Geoffroy Saint-Hilaire, 1817) and Common pandora (Pagellus erythrinus Linneaus, 1758)] obtained from 4 stations (Fethiye, Bodrum, Datça, Marmaris) in South Aegean coast were analyzed. After tissues were mineralized with wet-ashing, their heavy metal concentrations were measured with inductively coupled plasma mass spectrometry (ICP-MS). According to the findings, sediment samples had more heavy metals than water samples and none of heavy metal concentrations in the water samples exceeded national legal limits. Furthermore it was reported that the accumulation of heavy metal in liver and gill was the highest whereas in muscle the proportion was the lowest. Results showed that the mean concentration of the studied heavy metals in muscle tissues did not pose a risk in terms of public health in comparison with the international standards

Archeological research on the Karacadag and a hieroglyphic Luwian inscription from Karaören

This essay presents a partial report of surveys on the Karacadaǧ (Konya), which have been carried out since 2016 due to the find of a fragment of a hieroglyphic Luwian inscription from the 13th century BC at the village of Karaören. The results of the survey allow a holistic understanding of the material and topographic conditions which led to the writing, re-use and then find of the inscription. The inscription is presented and a possible historical-geographical framework both of this and of other related texts is explained, whereby it seems probable that there was an important military-strategic border here. The survey and associated ethnographic research established the importance of the freshwater springs on the Karacadaǧ, as well as the continuous re-use of stones attesting a profound cultural memory that runs from the Hittite period through a populous Byzantine occupation up until modern applications by the inhabitants of the Karacadaǧ

Electrical Size Reduction of Microstrip Antennas by Using Defected Ground Structures Composed of Complementary Split Ring Resonator

In this study the effects of using defected ground structures (DGS) composed of a complementary split ring resonator (CSRR) and CSRR with dumbbell (CSRR-D) for rectangular microstrip antennas are investigated. On this aim, two different antennas, which are Antenna B having CSRR etched DGS and Antenna C having CSRR-D etched DGS are designed and fabricated in comparison with the ordinary rectangular patch antenna, which is Antenna A. In both Antenna B and C, CSRR structures are etched in the same position of the ground planes. On the other hand, another ordinary microstrip antenna, called Antenna D, is designed at resonance frequency of Antenna C. For the characterization, resonance frequencies, voltage standing wave ratios, percentage bandwidths, gains, ka values and gain radiation patterns are investigated both in simulations and experiments. The numerical analyses show that 29.39 % and 44.49 % electrical size reduction (ESR) ratios are obtained for Antenna B and Antenna C, respectively in comparison to Antenna A. The experimental results verify the ESR ratios with 29.15 % and 44.94 %. Supporting, Antenna C promises 68.12 % physical size reduction (PSR) as it is compared with Antenna D. These results reveal that Antenna C is a good alternative for DGS based microstrip electrically small antennas

Protein and radioactivity levels of Patella coerulea linnaeus around Dardanelles

NATO Advanced Research Workshop on Ecological Standardization and Equidosimetry for Radioecology and Environmental Ecology -- APR 14-20, 2002 -- Kiev, UKRAINE[Anstract Not Available]NAT

The research of protein and radioactivity levels of Patella coerulea Linnaeus which is located around Urla

Patella coerulea LINNAEUS has been thought protein source and therefore collected from around the Bay of Urla, Turkey. Total nitrogen fat and dampness parameters were determined. Nitrogen levels are 16.925 total (N)% in Zeytinalam, 14.96 total (N)% in Karantina, 17.63 total (N)% in Iskele, 13.72 total (N)% in Bahkhova and total 13.13(N)% in Karaburun. Activity of Cs-137, K-40, Ra-226, Th-228 and gross gamma radioactivities of the samples were determined using a well type scintillation gamma spectrometer. The content of Cs-137 K-40, Ra-226, Th-228 radioactivity varies from 10 to 20 Bq/kg 354 to 489 Bq/kg, 0.36 to 0.62 Bq/kg and 0.14 to 0.37 Bq/kg respectively

Effective 3-D surface modeling for geographic information systems

In this work, we propose a dynamic, flexible and interactive urban digital terrain platform with spatial data and query processing capabilities of geographic information systems, multimedia database functionality and graphical modeling infrastructure. A new data element, called Geo-Node, which stores image, spatial data and 3-D CAD objects is developed using an efficient data structure. The system effectively handles data transfer of Geo-Nodes between main memory and secondary storage with an optimized directional replacement policy (DRP) based buffer management scheme. Polyhedron structures are used in digital surface modeling and smoothing process is performed by interpolation. The experimental results show that our framework achieves high performance and works effectively with urban scenes independent from the amount of spatial data and image size. The proposed platform may contribute to the development of various applications such as Web GIS systems based on 3-D graphics standards (e.g., X3-D and VRML) and services which integrate multi-dimensional spatial information and satellite/aerial imagery

Peri-implant hastalıklar

The treatment of partially or totally edentulous subjects with oral implants is a common procedure. Biological complications are occur around implants which are peri-implant mucositis and periimplantitis. Peri-implant mucositis is pathological condition which is normally localized in the soft tissues surrounding an oral implant. Peri-implantitis surrounding oral implants is an inflammatory process affecting the soft and hard tissues resulting in rapid loss of supporting bone associated with bleeding and suppuration. The diagnosis of peri-implant diseases is usually established by assessing probing depth, gingival index, bleeding on probing and radiographic bone resorption examinations. The etiopathogenesis of peri-implant diseases is related to the periimplant environment and to the soft tissues/implant interface, to patient-related factors (smoke, systemic diseases, plaque control) and to host-parasite equilibrium. Peri-implant diseases can be controlled successfully by providing mechanical, antiseptic, antibiotic and surgical supportive therapy, individually or combined.   ÖZET Tam veya kısmi dişsiz hastaların tedavisinde yaygın prosedürlerden biride oral implantlardır. İmplantların etrafında peri-implant mukositis ve peri-implantitis diye biyolojik komplikasyonlar meydana gelir. Peri-implant mukositis bir oral implantın etrafındaki normalde yumuşak dokuda lokalize patolojik bir durumdur. Oral implantların çevresindeki peri-implantitis süpürasyon ve kanama ile ilişkili destek kemiğin hızlı kaybı ile sonuçlanan, sert ve yumuşak dokuları etkileyen inflamatuar bir süreçtir. Peri-implant hastalıkların teşhisi genellikle sondalama cep derinliği, gingival indeks, sondalamada kanama ve radyografik kemik rezorbsiyon muayenesi ile kanıtlanır. Peri-implant hastalıkların etiyopatogenezi, peri-implant çevre ve yumuşak doku-implant yüzleşmesi, hasta ile ilişkili faktörler (sigara içme, sistemik hastalıklar, plak kontrolü) ve konak-parazit dengesi ile ilişkilidir. Peri-implant hastalıklar, tek tek veya kombine olarak mekanik, antiseptik, antibiyotik ve cerrahi destekleyici tedavi ile engellenerek başarılı olarak tedavi edilebilir. Anahtar kelimeler: İmplant, peri-implant hastalıklar, peri-implant mukositis, peri-implantitis ve tedavileri

How to teach usage of equipments in a remote laboratory

European Remote Radio Laboratory (ERRL) is an e-learning project for students, teachers and technicians of the universities who will use the very important devices of this laboratory remotely. These devices are very expensive to buy and can be broken easily while they have been using by the people who does not really know how to use them professionally. As a solution we have developed an e-learning system which aims to support the ERRL learners while studying on how to use equipments in the system. The system is developed according to the electronic performance support systems (EPSS) approach. An EPSS is a computer-based, well-structured system which improves the performance of individuals. It is an electronic infrastructure that contains, stores and distributes personal (individual) or corporate knowledge to enable people to reach necessary levels of performance in the fastest possible time and with minimum teaching support of other people. This paper discusses how the content for such a system is developed and how this content is interactively used in the EPSS platform. The technical details of the developed EPSS are also discussed in this study. We believe that this paper will help instructional system designers for designing different alternatives to improve learners' performance. © 2007 IEEE