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In this paper, an extended reduced-rank direction-of-arrival (DOA) estimation with unknown mutual coupling in uniform linear array (ULA) structure is presented. The proposed method is based on the joint iterative subspace optimization (JIO) and the auto-calibration of mutual coupling. Given an initial coupling vector, reduced-rank correlation matrix is estimated with the JIO approach, followed by iterative joint estimation of DOA and coupling with an auto-calibration algorithm. Simulation results show that both the proposed method and the existing auto-calibration method have similar performance in terms of DOA root mean square error, while the complexity of the proposed method is much lower than that of the auto-calibration approach due to the reduced rank.

In this study, we propose a novel method for a travel path inference problem from sparse GPS trajectory data. This problem involves localization of GPS samples on a road network and reconstruction of the path that a driver might have been following from a low rate of sampled GPS observations. Particularly, we model travel path inference as an optimization problem in both the spatial and temporal domains and propose a novel hybrid hidden Markov model (HMM) that uses a uniform cost search (UCS)-like novel combinational algorithm. We provide the following improvements over the previous studies that use HMM-based methods: (1) for travel path inference between matched GPS positions, the proposed hybrid HMM algorithm evaluates all candidate paths to find the most likely path for both the temporal and spatial domains. In contrast, previous studies either create interpolated trajectories or connect matched GPS positions using the shortest path assumption, which might not be true, especially in urban road networks (Goh et al. 2012; Lou et al. 2009). (2) The proposed algorithm uses legal speed limits for the evaluation of discrepancy in the temporal domain as in Goh et al. (2012), and Lou et al. (2009) only if there is not sufficient historical average speed data; otherwise, we use historical average speed computed from data. Our experiments with real datasets show that our algorithm performs better than the state of the art VTrack algorithm (Thiagarajan et al. 2009), especially for cases where GPS data is sampled infrequently.

Bu calismada ekmeklik bugdaylardan Triticum aestivum L. ve Triticum monococcum L. turlerine ait uc cesit kullanilmistir. Bitkiler cimlendirme odasinda yetistirilmistir. Kuraklik stresi altindaki bugday genotiplerininde nitrik oksit uygulamasinin etkileri calisilmistir. Anatomik calismalarda bitki ornekleri %70 alkolde fikse edilmistir. Yaprak enine kesitlerinin hazirlanmasinda parafin metodu kullanilmistir. Sonuclar tablo ve fotograflarda sunulmustur. Fotograflar Leica DM 3000 mikroskop ile cekilmistir. Bitki orneklerinin yaprak dokularindan alinan kesitlerde mikrometrik okuler yardimiyla anatomik olcumler yapilmistir. Bu sayisal sonuclar istatistiksel olarak ANOVA testi ile degerlendirilmistir.

This paper presents a line-of-sight (LoS) ship-to-ship wireless communication for millimeter radiowaves over the sea surface. 35 GHz and 94 GHz have been analyzed by our simulations as they are the frequencies of interest for the sea channels at millimeter radiowaves. The main time dispersion parameters of maritime channel such as mean excess delay, Root Mean Square (RMS) delay spread, coherence bandwidth (B c ), Doppler spread as well as coherence time and coherence distance have been investigated in this work. Cumulative Distribution Functions (CDFs) of time delay parameters indicate that the maritime channels can be assumed frequency non-selective as long as the bandwidth of transmitted signal does not exceed 750 MHz and 1.53 GHz at 35 GHz and 94 GHz, respectively. In addition, based on the results obtained from the Doppler spectrum, the sea channel is not affected by vessel movements and therefore the efficacy of Doppler frequency is negligible in maritime environments at these two frequencies. Consequently, the corresponding coherence times are relatively long enough not to cause distortion due to motion. As for the coherence distance, our results illustrate that the coherence distance for off shore marine channels is so large that it offers no space diversity over the sea channel.

With increasing population, the determination of traffic density becomes critical in managing urban city roads for safer driving and low carbon emissions. In this study, kernel density estimation is utilized in order to estimate traffic density more accurately when the speeds of vehicles are available for a given region. For the proposed approach, as a first step, the probability density function of the speed data is modeled by kernel density estimation. Then the speed centers from the density function are modeled as clusters. The cumulative distribution function of the speed data is then determined by Kolmogorov--Smirnov test, whose complexity is less when compared to the other techniques and whose robustness is high when outliers exist. Then the mean values of clusters are estimated from the smoothed density function of the distribution function, followed by a peak detection algorithm. The estimates of variance values and kernel weights, on the other hand, are found by a nonlinear least square approach. As the estimation problem has linear and nonlinear components, the nonlinear least square with separation of parameters approach is adopted, instead of dealing with a high complexity nonlinear equation. Simulations are carried out in order to assess the performance of the proposed approach. It is observed that the error between cumulative distribution functions is less than $1\% $, an indication that the traffic densities are estimated accurately. For an assumed traffic condition that bears five speed clusters, the minimum mean square error of kernel weights is found to be less than 0.00004. The proposed approach was also applied to real data from sample road traffic, and the speed center and the variance were accurately estimated. By using the proposed approach, accurate traffic density estimation is realized, providing extra information to the municipalities for better planning of their cities.

WOS: 000417480300020 This paper proposes a new heterogeneous network topology and a routing algorithm for a marine communication system involving ships and other marine vessels from a terrestrial point on the shore. Topology involves the use of a collection of Long-Term Evolution (LTE) systems and Wi-Fi mesh networks. There are multiple clusters/ships in the network, with an LTE system centered around each cluster. Communication between the clusters happens through LTE, and within the cluster mesh, networking is employed. Every end user in the ship has access to the server application by means of mesh networking from the respective access point in the cluster/ship. The routing algorithm is designed based on the best signal-to-interference-plus-noise-ratio path and minimum delay combination, which selects the best modulation scheme and hence the best data rate. The algorithm employs a new parameter that is derived from signal-to-interference-plus-noise ratio. The topology along with the algorithm provides a connection with a maximum coverage distance of 180 km and minimum data rate around 0.6 Mbps with 2 interconnection clusters. The presence of more interconnection clusters makes the coverage distance, data rate, and reliability greatly improved. Open source network tool Network Simulator 3 is used for the topology design, algorithm implementation, and simulations. The proposed topology and algorithm when implemented can be used to provide long-distance sea communication with improved reliability and higher data rate.

WOS: 000330637900005, PubMed ID: 24254651, The aim of this 7-year follow-up study was to determine respiratory changes in dental technicians. In our region, in the year 2005, 36 dental technicians were evaluated with a cross-sectional study on respiratory occupational diseases, and in 2012 we evaluated them again. Inclusion of information on respiratory symptoms and demographic features questionnaires was applied. Pulmonary function tests (PFT) were performed. Chest X-rays (CXR) were evaluated according to the ILO-2000 classification. For the comparisons of the technicians' findings in 2005 and 2012, data analyses were performed with the Wilcoxon test in addition to descriptive statistical procedures. In 2012, 19 out of the 36 technicians continued to work in the same place, so we were able to evaluate their findings. The prevalence of respiratory symptoms in dental technician was as follows: dyspnea 7 (37%), cough 6 (32%), and phlegm 5 (26%). According to ILO classifications in 2005, among the 36 technicians, 5 (13.8%) had pneumoconiosis. At the end of 7 years, there were 9 pneumoconiosis cases among the 19 remaining technicians (47%). Thus, there was a statistically significant progression on the profusion of the radiologic findings (p < 0.005). Also there was a significant worsening on spirometric findings (p < 0.05). In dental technicians, a determination of both radiologic and functional progressions at the end of 7 years demonstrate that the primary and secondary preventive measures are necessary for these workplaces. Workplaces must be regularly controlled for worker health and hygiene.

In this paper, cost optimization of an air cooling system was carried out by using Lagrange multipliers method, differential evolution algorithm and particle swarm optimization for various temperatures and mass flow rates which are inspiring the total cost of the system. It was aimed to show how differential evolution and particle swarm optimization approximates to the exact fitness values for various iterations. It is concluded that best fitness values can be obtained from both differential evolution algorithm and particle swarm optimization with a proper parameter initialization and these evolutionary methods can be used for larger and more complex energy systems including both mono and multi objective problems. A comprehensive comparison of corresponding optimization methods is performed for various system parameters and solution steps for evolutionary algorithms are discussed. PSO and DE gives high accuracy results within a short time interval comparing to LM method. Cost of the overall system can be minimized by lower air mass flow rates and temperature difference between air inlet and outlet in the system. Besides, increasing water mass flow rates and decreasing cooling tower temperatures provide lower capital cost.

In this paper we introduce some certain new sequence spaces via ideal convergence, λ-sequence and an Orlicz function in n-normed spaces and study different properties of these spaces and also establish some inclusion results among them.

WOS: 000322687800013, Background/purpose: One of the problems that has limited magnets' wide acceptance by clinicians is their low corrosion resistance. The purpose of this study was to determine the effect of corrosive environments and thermocycling on the attractive force of different types of new generation magnetic attachments. Materials and methods: We measured the attractive forces of 60 magnetic attachment systems (Hyper slim, Hicorex slim, Dyna, and Steco) with a universal test machine. We then immersed 40 of the magnetic attachment systems in two media, namely, 1% lactic acid solution (pH 2.3), and 0.9% NaCl solution (pH 7.3). The remaining magnetic attachments were put through 10,000 thermal cycles (5 degrees C/55 degrees C). We measured the attractive forces of the magnetic attachment systems again after immersion and thermocycling to compare data. The data were statistically evaluated with one-way analysis of variance, paired samples t-test, and post hoc Tukey-Kramer multiple comparison tests (alpha = 0.05). Results: We found significant differences between the mean values before and after immersion in corrosive environments (P < 0.05). In contrast to the Dyna and Steco systems (P < 0.001), the differences between the attractive forces before and after thermocycling were not statistically significant for the Hicorex slim and Hyper slim systems (P > 0.05). Conclusion: Magnetic attachments showed lower attractive force after immersion in corrosive environments compared to their initial retentive force. In addition, closed-field systems were not affected by the thermocycling procedures and were more resistant than open-field systems to thermal variations characteristic of the oral cavity. Copyright (c) 2012, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved., Cumhuriyet University Scientific Research Project (CUBAP), This investigation was supported in part by Cumhuriyet University Scientific Research Project (CUBAP). This study will be presented in a poster at the 10th International Congress of Academy of Prosthodontics and Gnathological Society, Antakya, Turkey, April 2012.

WOS: 000319978500005, PubMed ID: 23741995, Objective: The aim of this study was to evaluate the effect of different surface treatments: sandblasting, liners, and different laser irradiations on shear bond strength (SBS) of pre-sintered zirconia to veneer ceramic. Background data: The SBS between veneering porcelain and zirconium oxide (ZrO2) substructure was weak. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to veneering porcelain. There is no study that evaluated the bond strength between veneering porcelain and the different surface treatments on pre-sintered ZrO2 substructure. Methods: Two hundred specimens with 7mm diameter and 3mm height pre-sintered zirconia blocks were fabricated. Specimens were randomly divided into 10 groups (n = 20) according to surface treatments applied. Group C, untreated (Control); Group E, erbium: yttrium-aluminum-garnet (Er:YAG) laser irradiated; Group N, neodymium: yttrium-aluminum-garnet (Nd:YAG) laser irradiated; Group SB, sandblasted; Group L, liner applied; Group NL, Nd:YAG laser irradiated + liner applied; Group EL, Er:YAG laser irradiated + liner applied; Group SN, sandblasted + Nd:YAG laser irradiated; Group SE, sandblasted + Er:YAG laser irradiated; and Group SL, sandblasted + liner applied. The disks were then veneered with veneering porcelain. Before the experiment, specimens were steeped in 37 degrees C distilled water for 24 h. All specimens were thermocycled for 5000 cycles between 5 degrees C and 55 degrees C with a 30 sec dwell time. Shear bond strength test was performed at acrosshead speed of 1 mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern. Results: Surface treatments significantly changing the topography of the yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic according to scanning electron microscopic (SEM) images. The highest mean bond strength value was obtained in Group SE, and the lowest bond strength value was observed in NL group. Bond strength values of the other groups were similar to each other. Conclusions: This study shows that sandblasting + Er:YAG, sandblasting, Er:YAG + liner, sandblasting + Nd:YAG, and Er:YAG laser treatment on pre-sintered ZrO2 substructure increased the bond strength to veneering porcelain, compared with other surface treatments. After different surface treatments, there was no difference in surface roughness of pre-sintered zirconia to compare after sintering; sintering enhanced the bond strength within the limitations of present study.

This work presents and analyzes the results of millimeter-wave propagation simulations performed for over the sea LoS ship to ship communication channels. We present a channel characterization study where channel parameters such as path loss, received power, RMS delay spread, and power delay profile are obtained by using a ray tracing approach. 5G candidate frequencies, 35 GHz and 94 GHz were chosen as the primary bands of interest since these two bands have minimum water and oxygen attenuation, thereby promising better performance among the other frequency bands. Our results indicate that 2-ray analytical propagation loss model should only be used for short ranges over the sea surface propagation at typical frequencies considered by 5G. However, free space path loss model cannot predict the behavior of channel over the sea surface in high frequencies even for short ranges. Therefore, in this study a new model that is the modified version of 2-ray path loss model is proposed, in which a coefficient in the power of exponential function is introduced to better predict the behavior of maritime channels of 5G. It is shown that the proposed model can predict the path loss of maritime channel better than the existing models.

WOS: 000381215800009, PubMed ID: 27249215, Objective: Laser modalities instead of conventional surface treatment techniques have been suggested to obtain an adequate micromechanical bonding between dental super-and infrastructures. The present study was undertaken to assess the effect of surface treatment with Ho: YAG, Er: YAG, and Nd:YAG laser modalities on the shear bond strength (SBS) of ceromer to different types of metal infrastructures in in vitro settings. Methods: The study specimens consisted of 40 direct laser sintered (DLS), 40 Ni-Cr-based, and 40 zirconium oxide (ZrO2) infrastructures. In each infrastructure group, the specimens were divided randomly into five treatment modalities (n = 8): no treatment (controls), sandblasting, Er: YAG, Nd: YAG, and Ho: YAG lasers. The DLS, Ni-Cr-based, and ZrO2 infrastructures were prepared in the final dimensions of 7 mm in diameter and 3 mm in thickness in line with the ISO 11405 standard. Ceromer as superstructure was applied to all the infrastructures after their surface treatments according to the selected treatment modality. SBS test was performed to test the effectiveness of surface treatments. A stereomicroscope was used to determine the changes in the surface morphology of specimens. Results: Among the laser modalities and sandblasting, Ho: YAG laser caused the most important increase in the DLS and Ni-Cr-based infrastructures but sandblasting caused the most important increase in the ZrO2 infrastructure. In all the infrastructures, Nd: YAG laser has the least effectiveness, and Er: YAG laser makes an intermediate success. The stereomicroscopy images presented that the applications of laser surface treatments altered the surface in all the infrastructures. Conclusions: Overall, in current experimental settings, Ho: YAG, Nd: YAG, and Er: YAG lasers, in order of strength, are effective in improving the bonding of ceromer to all the infrastructures. Ho: YAG laser is more effective in the DLS and Ni-Cr-based infrastructures, but sandblasting is more effective in the ZrO2 infrastructure. The studied laser modalities need to be subjected for further studies to determine their appropriate settings and the specifications to be used in prosthodontics.

In recent years there has been a rapid increase in indoor applications of mobile robots, where the knowledge of real-time location has become more and more important. In this framework, the methods about the location estimation are gaining the focus under the umbrella of Indoor Positioning technology, which is suitable for location-based applications. Here, for the purpose of dynamic and static tracking of a mobile user's location, we combine RSS (Received Signal Strength) measurement of WLANs (Wireless Local Area Networks) with the dynamic modeling of the mobile user. The joint approach is preferred for the minimization of the errors that are bound to occur due to RSS and to improve the accuracy of the overall estimation. This is accomplished through Non-Parametric Information Filter (NI Filter), which does not require an explicit information concerning RSS-position, and the Likelihood Density Estimation, which has low-error rate performance. The overall approach enabled us to develop two algorithms for different dynamic motions. Experimental results are obtained by actual measurements in an office environment and ARMSE (Average Root Mean Square Error) has been used as the assessment criteria. The study in mitigating the difficulties arising due to the unpredictable nature of RSS in indoor environment presented an improvement of 5,15m (49,76 %) in positioning error relative to Memoryless Positioning alone.

It is anticipated that the existing analog use of the frequency modulation (FM) band (87.5–108 MHz) will ultimately be replaced by contemporary digital systems beyond 3G. Before such a transition is realized, it is important to understand the channel characteristics of the FM band in order to perform preliminary studies before deployment of new systems. Hence, in this paper, for the FM band, we introduce a directional wireless channel model suitable for dense hilly terrain regions. The model is a modified version of the existing COST 259 for ~2 GHz. Physical modifications and new concepts are introduced in order to extend the existing models and to fit the characteristics of the FM band. With the introduced modifications, a directional channel model suitable for the FM band is developed. The new model is verified through comparisons with some existing measurements for the bands near the FM band and through simulations using Wireless Insite software, a commercially available radio-frequency ray tracing tool. With the developed model, it is anticipated that contemporary wireless systems considered to be operated in the FM band can be better assessed for their performance measures.

This paper presents the following definition which is a natural combination of the definitions for almost asymptotically equivalence and almost statistical convergence of fuzzy numbers. Let θ = be a lacunary sequence. The two sequences and of fuzzy numbers are said to be asymptotically θ −statistical equivalent of multiple provided that for every e > 0 lim ∈ : ! , # ≥ e% = 0, uniformly in & (denoted by ~ (θ) * ) and simply almost asymptotically−statistical equivalent if = 1. Also, we prove that some inclusion relations. 2010 Mathematics Subject Classification. 40A05, 40A35, 40G15, 03E72.

WOS: 000298152400006, PubMed ID: 22150095, Objective:The aim of this study was to evaluate the effect of different surface treatments; sandblasting, Er:YAG, Nd:YAG, or CO2 laser irradiation on the shear bond strength (SBS) of zirconia ceramic to dentin. Background data:Zirconia is not properly luted with resin cements. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to resin cements. There is no study that compared the effect of different laser types (Er:YAG, Nd:YAG, CO2) with sandblasting on SBS between zirconia and dentin. Methods:One hundred and twenty human maxillary third molar teeth were sectioned 3mm below the occlusal surfaces, embedded in a metal ring with autopolymerizing acrylic resin, and stored in distilled water at 37(0)C. One hundred and twenty disc-shaped zirconia specimens were fabricated (6mm in diameter and 4mm in thickness), and randomly assigned to six groups (n = 20):Group 1, untreated (control); Group 2, sandblasted; Group 3, Er:YAG laser irradiated; Group 4, Nd:YAG laser irradiated with contact; Group 5, Nd:YAG laser irradiated with non-contact; Group 6, CO2 laser irradiated. They were cemented onto the dentin with dual-cured resin cement (Variolink (R)). After they were stored in distilled water at 37(0)C for 24 h, the SBS test was performed at a crosshead speed of 1mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern. Results:Results of this study did not show statistically significant differences between Groups 1 and 2, or among Groups 3, 4 and 5. The lowest SBS was recorded in Group 6 (CO2 laser), and the highest SBS was recorded in Group 4 (Nd:YAG laser with contact), followed by Group 3 (Er:YAG laser). The adhesive failure mode was predominantly observed in Groups 2, 3, 5, and 6. Group 1 showed 45% mixed failure and Group 4 showed 50% mixed failure. Conclusions:This study shows that Er:YAG and Nd:YAG laser treatment increased the bond strength of zirconia compared to sandbasting and CO2 laser treatment.

Triple sequence convergence has an extremly important position in the basic theory of mathematics. The present manuscript contains four types of convergence concept of convergence almost surely, convergence incredibility, trust convergence in mean and convergence in distribution and discuss the relation ship among those and some mathematical properties of those new convergence.

We introduce and study some basic properties of Bernstein-Stancu polynomials of rough I-convergent of triple sequence spaces and also study the set of all Bernstein-Stancu polynomials of rough I-limits of a triple sequence spaces and relation between analytic ness and Bernstein-Stancu polynomials of rough I-core of a triple sequence spaces.

Ranging is one of the most important processes in the mobile WiMAX standard. Power adjustment, timing offset estimation, and synchronization between a base station (BS) and all users within a cell are done through the ranging process referred to as initial ranging. In this paper, we discuss the details of initial ranging together with some of the proposed algorithms, as well as a novel algorithm to carry out a successful ranging process. Performance curves and computational complexity comparisons are presented. The system performance is evaluated for both additive white Gaussian noise (AWGN) channels and practical multipath fading channels with multiuser interference. It is shown that the proposed algorithm offers a reduced complexity ranging method that can be employed in practical WiMAX-based BSs.

It is so crucial to know traffic density to manage traffic effectively and act on roads accordingly for safer driving. In this paper, Kernel Density Estimation is used to estimate traffic density by assuming velocity information is known for a given region. Also, kernel weights will be found by using Kolmogorov-Smirnov Tests, since its complexity is less than other methods, and linear Least Square, because it makes approach simpler. We are able to estimate the density with the proposed method and the error between CDF is so small, for an example system which has twelve weights, the error is 8.7667 × 10 -7 . By using our approach, methods can be developed to predict traffic density.

WOS: 000353855300003, PubMed ID: 25932307, PURPOSE. The aim of this study was to appraise the some mechanical properties of polymethyl methacrylate based denture base resin polymerized by copolymerization mechanism, and to investigate the cytotoxic effect of these copolymer resins. MATERIALS AND METHODS. 2-hydroxyethyl methacrylate (HEMA) and isobutyl methacrylate (IBMA) were added to monomers of conventional heat polymerized and injection-molded poly methyl methacrylate (PMMA) resin contents of 2%, 3%, and 5% by volume and polymerization was carried out. Three-point bending test was performed to detect flexural strength and the elasticity modulus of the resins. To determine the statistical differences between the study groups, the Kruskall-Wallis test was performed. Then pairwise comparisons were performed between significant groups by Mann-Whitney U test. Agar-overlay test was performed to determine cytotoxic effect of copolymer resins. Chemical analysis was determined by FTIR spectrum. RESULTS. Synthesis of the copolymer was approved by FTIR spectroscopy. Within the conventional heat-polymerized group maximum transverse strength had been seen in the HEMA 2% concentration; however, when the concentration ratio increased, the strength decreased. In the injection-molded group, maximum transverse strength had been seen in the IBMA 2% concentration; also as the concentration ratio increased, the strength decreased. Only IBMA showed no cytotoxic effect at low concentrations when both two polymerization methods applied while HEMA showed cytotoxic effect in the injection-molded resins. CONCLUSION. Within the limitations of this study, it may be concluded that IBMA and HEMA may be used in low concentration and at high temperature to obtain non-cytotoxic and durable copolymer structure.

For the practical LMMSE channel estimation of MIMO-OFDM systems, the high computational complexity of LMMSE needs to be eliminated. In this study, we develop a low-complexity, generalized low-rank LMMSE channel estimator for MIMO-OFDM systems using comb-type pilots. The estimator utilizes the relationship between the subspaces of the frequency domain channels at the pilots and non-pilots subcarriers. By using subspace tracking, it is observed that practical LMMSE channel estimation of MIMO-OFDM systems can be feasible

The use of multiple antennas has found various applications in the area of wireless communications. One such application has recently become very popular and is referred to as the multiple-input multiple-output (MIMO) antenna system. The main idea behind MIMO is to establish independent parallel channels between multiple transmit and receive antennas. Each channel uses the same frequency, and the transmissions occur simultaneously. In such a configuration, the amount of data transmitted increases linearly with the number of parallel channels, which is what makes MIMO so popular in the wireless world. The enormous capacity offered by MIMO systems is not realizable when the parallel channels are highly correlated. The goal of this article is to highlight the correlation concept and its impact on MIMO systems. Although correlation can be defined in many dimensions, here we focus on spatial correlation, and specifically consider antenna correlations in mobile units. We provide an overview of spatial correlation and present its underlying parameters in detail. Special attention is given to mutual coupling since it has signal decorrelation and antenna gain reduction effects. We then present how correlation in a MIMO system affects the amount of data that can be transmitted (MIMO capacity) and briefly review how power should be distributed with the knowledge of correlation. Analyses indicate that in real propagation environments, the high capacity gain of MIMO systems can be realized with improved antenna selection algorithms and power allocation strategies.

Rare earth magnets have been used in both prosthodontics and orthodontics, but their corrosion tendency in the oral cavity limits long term clinical application. The purpose of this study was to evaluate corrosion of new generation magnetic attachments in two different pH corrosive environments and to answer the question: 'can corrosion reach the magnet in spite of laser welding?'. Forty magnetic attachment systems (Hyper slim, Hicorex slim, Dyna and Steco) were immersed in two media, 1% lactic acid solution (pH=52.3) and 0.9% sodium chloride solution (pH=57.3) for 14 days. After immersion, samarium, cobalt, neodymium and boron ions released from the magnetic attachments were analysed using inductively coupled plasma mass spectrometry. Moreover, iron ions released from the magnetic attachments were detected by atomic absorption spectroscopy. The data were statistically evaluated with Kruskal-Wallis and post hoc Tukey-Kramer multiple comparisons test (?=50.05). In all groups, Dyna, Hicorex slim, Hyper slim and Steco, there were statistically significant differences between sodium chloride and lactic acid solutions. Different amounts of neodymium, boron, iron, samarium and cobalt ions released from magnetic attachments were detected in the corrosive environments. There was a significant decrease in the corrosion of the magnets, but corrosion was not completely stopped. Laser welding zone was broken down, and corrosion reached the magnet. © W. S. Maney & Son Ltd. 2011., Akin, H.; Department of Prosthodontics, Faculty of Dentistry, University of Cumhuriyet, Sivas, Turkey; email: drhknkn@hotmail.com

Inprosthodontics, to increase the bonding of metals with porcelain by severalmeans including laser surface treatments is still an important research topic.The current study was undertaken to evaluate the influence of surface treatmentwith Ho:YAG, Er:YAG, and Nd:YAG lasers on the shear bond strength (SBS) of lowfusion dental porcelain to titanium and zirconium oxide substructures. Titanium(n=70) and zirconium oxide (n=70) specimens were categorized into 7 studygroups (n=10): sandblasting, Er:YAG 1.5W and 2.5W, Nd:YAG 1.5W and 2.5W, andHo:YAG 4W and 10W. Their surface morphology was examined with under scanningelectron microscopy (SEM) after surface treatment. After application of lowfusion dental porcelain, the SBS test was performed applying a universaltesting machine. In the titanium specimens, the SBSs of the Nd:YAG laser 2.5Wand 1.5W were significantly higher than those of the sandblasting and otherlasers, respectively (p, Protetikdiş tedavisinde lazer yüzey uygulamalarını da içeren birçok yöntem, porselenalt yapı ile metalin bağlantısını arttırmak için halen önemli bir araştırma konusudur.Çalışma; titanyum ve zirkonyum oksit alt yapılara uygulanan düşük ısıporseleninin makaslama bağlantı dayanımına (SBS); Ho:YAG, Er:YAG ve Nd:YAGlazer ile yüzey şartlandırmalarının etkisini geliştirmeyi amaçlamıştır. Titanyum(n=70) ve zirkonyum oksit (n=70) örnekler 7 çalışma grubuna ayrılmıştır (n=10):Kumlama, Er:YAG 1.5 W ve 2.5 W, Nd:YAG 1.5 W ve Er:YAG 2.5 W, ve Ho:YAG 4W VE10 W. Yüzey morfolojileri, şartlandırma sonrasında taramalı elektron mikroskobu(SEM) altında incelenmiştir. Dental düşük ısı porseleninin uygulanmasındansonra SBS testi universal test makinesi kullanılarak yapılmıştır. Titanyum örneklerde Nd:YAG lazer 2.5 W ve 1.5W SBS sırasıyla kumlama ve diğer lazerlerden önemli ölçüde yüksektir(p

Objectives:To investigate bond strengthbetween Estenia, is a kind of seromer has beenincreasingly used in dentistry, low fusing porcelainand titanium metal sub-structures after differentsurface treatments.Materials and Methods: In the present study,ISO9693:1999 standards 25x3x0.5mmdimensionsof the samples used prepared with titanium in themetal substructure. Metal sample surface blasting(n=12) and Nd-YAG laser with a blasting + laser(n=12) by application of the working groups wereformed. Low-temperature materials as porcelainsuperstructure estenia seromer group size 8x3x3mmmetal substructure to be appliedaccording to the instructions of the manufacturer.Later examples, universal testing device todetermine the three-point transverse fractureresistance test was performed. Unit load applicationrate of 0.5 mm/min and the distance between thejaws adjusted to 20 mm. Example of porcelainmetal sub-structure, divided into groups, the type ofthe current connection N/mmstrength values wererecorded. Mann-Whitney U test was used for theevaluation of the data obtained.Results: Titanium metal sub-structures in termsof strength of connection estenia materialdetermined to be sufficient, can be a seriousalternative to high temperature porcelains weredetected. However, the Nd: YAG laser irradiationof titanium surface connection valueswere determined in a value increase, but statistically notsignificant.Conclusion:Blasting and sandblasting +samples compared to laser therapy, sand blasting +laser groups showed no statistically significantdifferences in terms of connection strength.(p>0.05)., Amaç: Diş hekimliğinde kullanımları giderek yaygınlaşan seromer grubundan Estenia düşük ısı porseleninin, titanyum metal alt yapılarla farklı yüzey şartlandırmalarında bağlantı dayanımı değerlendirmektir. Gereç ve Yöntem: Çalışmamızda titanyumdan ISO-9693:1999 standartlarına göre 25x3x0,5mm3 ebatlarında hazırlanan metal alt yapı örnekleri kullanıldı. Metal örnek yüzeylerine kumlama (n=12) ve Nd-YAG lazeri ile kumlama+lazer (n=12) uygulamaları yapılarak çalışma grupları oluşturuldu. Üst yapı porseleni olarak seromer grubundan estenia düşük ısı materyali 8x3x3mm3 ebatlarında metal alt yapı üzerine üretici firma talimatlarına uygun olacak şekilde uygulandı. Daha sonra örneklere, transvers dirençlerinin tespit edilmesi amacıyla üniversal test cihazında üç nokta bükme testi uygulandı. Cihazın yük uygulama hızı 0,5 mm/dak ve çeneler arası mesafe 20mm olacak şekilde ayarlandı. Örnek gruplarında porselenin metal alt yapıdan ayrıldığı andaki bağlantı dayanım değerleri N/mm2 türünden kaydedildi. Elde edilen verilerin değerlendirilmesinde Mann-Whitney U testi kullanıldı. Bulgular: Kumlama ve kumlama+lazer uygulanan örnekler kıyaslandığında, kumlama+lazer gruplarında bağlantı dayanımı yönünden istatistiksel anlamlı bir fark izlenmedi. (p > 0,05). Sonuç: Titanyum metal alt yapılara bağlantı dayanımı yönünden yeterli seviyede olduğu belirlenen estenia materyalinin, yüksek ısı porselenlerine ciddi bir alternatif olabileceği tespit edildi. Bununla birlikte Nd:YAG lazer uygulamasının titanyum yüzey bağlantı değerlerini artırdığı ancak istatistiksel olarak anlamlı bir fark oluşturmadığı belirlendi.

Auricular defects may be congenitally or occur secondary to trauma or surgical removal of a neoplasm. Treatment options for the reconstruction of the ear may include either plastic surgery or provision of an auricular prosthesis. The requirements of prosthesis are esthetics, retention and stability, alignment and positioning, biocompatibility, and longevity. In the present study, 2 patients (a partial and a total auricular defects) were rehabilitated with epistheses that were constructed on endosteal titanium implants of the ITI system with magnetive anchors in mastoid process. The success of both 2 epithesis compared in terms of function, aesthetics and psychological activity., Ozdemir Dogan, D.; Cumhuriyet University, Faculty of Dentistry, Department of Prosthodontics, 58140 Sivas, Turkey; email: dtderya@hotmail.com

This paper formulates a new model for crossline reconstruction that relies on aliased, 3D decomposed, up- and downgoing waves. It also presents a closed form approach to solve the joint reconstruction and 3D deghosting problem. The new model provides additional insight into how the ghost reflection and the vertical component of particle velocity/acceleration are exploited in crossline reconstruction and joint 3D deghosting solutions for towed streamer applications.

In this paper, we introduce some new double sequence spaces defined by Orlicz function and study different properties of these spaces and also establish some inclusion results among them.

A multicomponent towed streamer measures both pressure and the particle velocity vector. The particle velocity vector enables us to calculate the 3D upgoing wavefield at any desired position within the aperture of the seismic spread and this allows improving not only the temporal bandwidth by removing ghost notches, but also the spatial bandwidth. However, particle motion sensors measure streamer-borne noise with amplitudes typically several orders of magnitude stronger than the corresponding noise recorded by hydrophones at frequencies below about 20 Hz. Therefore, stronger noise attenuation for particle velocity data is needed at these frequencies. In this paper, we introduce a multiscale noise attenuation algorithm that provides a high-fidelity particle motion measurement at frequencies down to 3 Hz.

Summary A multicomponent (4C) towed streamer measures both pressure and the particle velocity vector. The particle velocity vector enables us to calculate the 3D upgoing wavefield at any desired position within the aperture of the seismic spread and this allows improving not only the temporal bandwidth by removing ghost notches, but also the spatial bandwidth. However, particle motion sensors measure streamer-borne noise with amplitudes typically several orders of magnitude stronger than the corresponding noise recorded by hydrophones at frequencies below about 20-Hz. Therefore, stronger noise attenuation for particle velocity data is needed at these frequencies. In this paper, we introduce a multiscale noise attenuation algorithm that provides a high-fidelity particle motion measurement at frequencies down to 3 Hz. We also show that the new technique provides improved noise attenuation on pressure data.

WOS: 000322832200010, PubMed ID: 22724624, Objective. The aim of this study was the histopathological evaluation of the effects of the fiber reinforced acrylic resins on living tissues. Materials and methods. The study was performed on 21 rabbits. Three groups, each including seven subjects, were formed. There was no applied plate in the control group. For the second group, heat-polymerized acrylic resin plates were inserted. For the third group, heat-polymerized acrylic resin plates containing proportionally 5% chopped silanated E type glass fiber were inserted. Plates were fixed to the palatine bone of the rabbits with titanium screws. Before the implementation of the plates and 1 month after the plates were applied, soft tissue samples were taken from the buccal mucosa of the rabbits. Also, tissue samples were taken from the control group. All samples were evaluated histopathologically. Results. In the control group, only a focal atrophy was observed. In the acrylic group, large decomposition containing erythrocytes under the parahyperkeratotic region and micro-vesicle like spongiotic tissue reactions were observed. In the fiber reinforced acrylic group, widespread focal atrophy, bulgy look of the epithelium cells similar to apoptosis, over-distension and sub-corneal decomposition had been observed. In terms of atrophy and hyperkeratosis there were no statistically significant differences among groups. However, in respect to sub-corneal decomposition, there was a statistically significant difference in the fiber reinforced group (p < 0.01). Conclusions. The statistically significant difference in the sub-corneal decomposition of the fiber reinforced group had made us think that fiber edges had a traumatic effect on the reaction.

Summary In this paper, we generalize the optimal deghosting (ODG) method used for deghosting over/under data to combine pressure (P) and vertical velocity (Z) data recorded with a 4C multi-component streamer to reduce the impact of the noise on the deghosted data. The ODG approach uses pressure and velocity ghost models and the statistics of the residual noise to minimize, in a least-squares sense, the noise on the up-going/deghosted wavefield. ODG and the standard PZ summation (PZSUM) combinations are applied to pressure and velocity data recorded in the North Sea (2-D acquisition). We show that both methods attenuate the receiver ghost, fill in information at the pressure notch frequencies and that ODG has the least postcombination noise level. We also show pre- and post-stack vertical velocity data with encouraging signal-to-noise ratios. Some differences between the ODG and PZSUM combination results can be explained using the cross-line component measurement. Finally, in order to further improve the PZ deghosted data, we suggest a toolbox approach that takes advantage of both ODG and PZSUM combinations and accounts for the varying signal-to-noise ratios observed on multi-component streamer data.

Most current Doppler spread (DS) estimators are based on the wireless channel auto-correlation function. In these methods, the DS estimation variance is high, especially due to channel estimation errors. Furthermore, in a time-varying velocity scenario, DS varies over time, which adds extra complexity to the estimation process. In this study, we propose a GPS-aided DS estimation scheme that incorporates accurate velocity information to reduce estimation variance in a mobile system. The Cramer-Rao lower bound method and the maximum likelihood estimation method are used in the proposed estimators. Through simulations, we show that the DS variance is significantly reduced with the proposed estimators.

The purpose of this study was to investigate the tensile strength of the bond between a silicone lining material and heat-cured polymethyl methacrylate (PMMA) denture base resin after Er:YAG laser treatment with different pulse durations and energy levels. PMMA test specimens were fabricated and each received one of six surface treatments: no treatment (control), and five Er:YAG laser treatments comprising (1) 100 mJ, 1 W, long pulse duration, (2) 200 mJ, 2 W, long pulse duration, (3) 200 mJ, 2 W, very short pulse duration, (4) 300 mJ, 3 W, long pulse duration, and (5) 400 mJ, 4 W, long pulse duration. The resilient liner specimens (n=15) were processed between two PMMA blocks. The tensile strengths of the bonds between the liners and PMMA were determined using a universal testing machine at a crosshead speed of 5 mm/min. The mode of failure was characterized as cohesive, adhesive, or mixed modes. One-way ANOVA and the post hoc Tukey-Kramer multiple comparisons test were used to analyze the data (?=0.05) . There was a statistically significantly difference in tensile bond strength between laser-treated and untreated specimens (P, Akin, H.; Department of Prosthodontics, Faculty of Dentistry, University of Cumhuriyet, 58140, Sivas, Turkey; email: drhknkn@hotmail.com

This article has been retracted at the request of the editor since part of the text was found to have already appeared verbatim in Bipan Hazarika and Ekrem Savas, “Some I-convergent lambda-summable difference sequence spaces of fuzzy real numbers defined by a sequence of Orlicz functions”, Mathematical and Computer Modelling 54 (2011) 2986–2998. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data, text, or figures should be properly cited. As such this article represents a violation of our publishing policies and ethical standards. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy .

Purpose: The aim of this study was to assess the cytotoxicity of different types of alginate impression materials. Material and Method: Cavex CA37, A3KROM, ALGINPLUS FAST ve ORALGHINE alginate impression materials were used. According to the manufacturer’s instructions, alginates were mixed with serum physiological to obtain alginate specimens. Specimens were performed in sterile with ethylene oxide gas and then placed on to the L929 fibroblast cell culture. According to the 1999 ISO 10993-5 protochols, cytotoxicity were determined by means of agar overley test. Results: According to the lisis of the cells, ORALGH, Amaç: Bu in vitro çal man n amac , farkl tipteki aljinat ölçü maddelerini sitotoksisite yönünden de erlendirmektir. Gereç ve Yöntem: Farkl tipteki dört aljinat, Cavex CA37, A3KROM, ALGINPLUS FAST ve ORALGHINE, üretici firmalar n talimatlardo rultusunda belirtilen oranlarda, serum fizyolojik ile kar t r larak aljinat numuneleri haz rland . Haz rlanan numuneler etilen oksit gaz yla steril edildi ve L929 fibroblast hücre serisi kullan larak elde edilen kültüre yerle tirildi. Agar overley testi kullan larak sitotoksisitenin belirlenmesinde ISO 1999 y l 10993-5 numaral protokolü takip edildi. Bulgular: Hücrelerin lizis miktar na göre yap lan puanlama de erleri ORALGH

Purpose: The aim of this study was to investigate the relationship between dental erosion and GERD. Material and Methods: A total of 100 patients; 50 patients diagnosed with GERD and 50 patients as a control were involved in this study. The patients are classified as their sex, the place of erosion, oral hygiene habit and the degrees of erosion. Oral examination to quantify loss of tooth structure was done by scale of Eccles. Results: In this study the prevalance of dental erosion in patient with GERD was found 80%. Erosion of anterior teeth’s palatinal surfaces was observed more than the erosion of posterior teeth’s buccal and occlusal surfaces. In terms of sex it was analyzed that the GERD patients of men’s teeth (% 96) became more erosion than the GERD patients of women’s (% 65). Conclusion: The people having GERD illness may appear teeth erosion in a high ratio. Because of this reason, at the systemic diseases, the protector and prothetic treatment of teeth and medical treatment can be suggested. ÖZET Amaç: Bu çalışma gastrointestinal reflü hastalığı ile diş erozyonu arasındaki ilişkinin incelenmesi amacı ile yapıldı. Gereç ve Yöntem: Bu çalışma 50 kişi kontrol grubu, 50 kişi Gastroözofagal Reflü hastası toplam 100 kişi üzerinde yapıldı. Hastalar, cinsiyet, erozyonun bulunduğu yer, oral hijyen alışkanlığı ve erozyonun derecesine göre sınıflandırıldı. Diş yapısındaki kaybın derecesi Eccles skalasına göre belirlendi. Bulgular: GÖR hastaların % 80’inde çeşitli derecelerde aşınma olduğu tespit edildi. Kesici dişlerin palatinal yüzlerindeki aşınma, posterior dişlerin bukkal ve okluzal yüzlerindeki aşınmalardan daha fazla olduğu görüldü. Cinsiyet yönünden ise GÖR’lü erkeklerin (% 96) bayanlara ( % 65) oranla daha fazla diş aşınmaları olduğu tespit edildi. Sonuç: GÖR hastalığı olan bireylerde dişlerde erozyon görülme yüzdesi fazla olup, bu nedenle sistemik hastalığın ilaçla tedavisi ve dişlerde koruyucu ve protetik tedavilerin yapılması önerilebilir. Anahtar Kelimeler: Gastroözofagal reflü, diş erozyonu, Amaç: Bu çal ma gastrointestinal reflü hastal ile di erozyonu aras ndaki ili kinin incelenmesi amac ile yap ld .Gereç ve Yöntem: Bu çal ma 50 ki i kontrol grubu, 50 ki iGastroözofagal Reflü hastas toplam 100 ki i üzerinde yap ld .Hastalar, cinsiyet, erozyonun bulundu u yer, oral hijyen al kanl ve erozyonun derecesine göre s n fland r ld . Di yap s ndaki kayb nderecesi Eccles skalas na göre belirlendi. Bulgular: GÖR hastalar n % 80’inde çe itli derecelerde a nma oldu u tespit edildi. Kesici di lerin palatinal yüzlerindeki a nma, posterior di lerin bukkal ve okluzal yüzlerindeki a nmalardan daha fazla oldu u görüldü. Cinsiyet yönünden ise GÖR’lü erkeklerin (% 96) bayanlara ( % 65) oranla daha fazla di a nmalar oldu u tespit edildi. Sonuç: GÖR hastal olan bireylerde di lerde erozyon görülme yüzdesi fazla olup, bu nedenle sistemik hastal n ilaçla tedavisi ve di lerde koruyucu ve protetik tedavilerin yap lmas önerilebilir

Purpose: In this study different implant systems were evaluated mechanically. Material and Method: 101implants including MIS, ITI, Biolok and Biotec implants in 32 patients which were good general health status. The implants were followed up over a period of 2 years and mechanical failure of the implants was evaluated. Results: One implant fracture, 2 screw fracture and 18 screw and abutment loosening were observed. The two-year short follow up success rates were %87,23 for MIS implants, %86,20 for ITI implants, %55,55 for Biolok implants and %75 for Biotec implants. Conclusion: Abutment and screw loosening was observed to the most common prosthetic complication. We observed greater success rates for ITI implants and also MIS implants, however, long-term follow up is needed to verify the long-term success MIS, Biolok and Biotec implant systems. ÖZET Amaç: Bu çalışmada farklı implant sistemlerinin, kısa dönem, mekanik açıdan başarıları değerlendirilmiştir. Gereç ve Yöntem: Sistemik olarak sağlıklı 32 hastada, MIS, ITI, Biolok ve Biotec implant sistemlerinden oluşan 101 adet implant uygulanmıştır. İmplantlar 2 yılı aşkın bir süre takip edilmiştir ve mekanik başarısızlıklar değerlendirilmiştir. Bulgular: 1 implant kırığı, 2 vida kırığı ve 18 vida ve abutment gevşemesi tespit edilmiştir. İki yılı aşkın bir süreçte, implantların kısa dönem başarısı MIS için %87.23, ITI için %86.20, Biolok için %55.55 ve Biotec için %75 olarak bulunmuştur. Sonuç: Vida ve abutment gevşemesinin en sık görülen protetik komlikasyon olduğu görülmüştür. ITI ve MIS implant sistemleri önemli ölçüde başarılı bulunurken, MIS, Biolok ve Biotec implant sistemleri için uzun dönem çalışmaları gerekmektedir., Amaç: Bu çal mada farkl implant sistemlerinin, k sa dönem, mekanik aç dan ba ar lar de erlendirilmi tir. Gereç ve Yöntem: Sistemik olarak sa l kl 32 hastada, MIS, ITI, Biolok ve Biotec implant sistemlerinden olu an 101 adet implant uygulanm t r. 'mplantlar 2 y l a k n bir süre takip edilmi tir ve mekanik ba ar s zl klar de erlendirilmi tir. Bulgular: 1 implant k r , 2 vida k r ve 18 vida ve abutment gev emesi tespit edilmi tir. 'ki y l a k n bir süreçte, implantlar n k sa dönem ba ar s MIS için %87.23, ITI için %86.20, Biolok için %55.55 ve Biotec için %75 olarak bulunmu tur. Sonuç: Vida ve abutment gev emesinin en s k görülen protetik komlikasyon oldu u görülmü tür.ITI ve MIS implant sistemleri önemli ölçüde ba ar l bulunurken, MIS, Biolok ve Biotec implant sistemleri için uzun dönem çal malar gerekmektedir

Dear Colleagues, We are pleased that the September 2011 issue of the Cumhuriyet Dental Journal has published. Thank you very much to all authors and reviewers for their contributions. Dr. Rosenstiel, Dr. Mericske, Dr. Palma-Dibb, Dr. Ozcan, Dr. Cho, Dr. Sauro, Dr. Abdalla, Dr. Ozer, Dr. Nuvvula, Dr. Jafarzadeh, Dr. Tezvergil-Mutluay, Dr. Mutluay, and Dr. Gursoy have joined our editorial board. We are are grateful to them for joining our family. Our journal is now indexed in Index Copernicus and under evaluation in Ulakbim (Türk Tıp Dizini). We know that this is only the beginning and we hope that our journal will be indexed in expanded science citation index in the coming months.I owe a 'Thank you' to each and every member of our editorial board for their hard work. Hope to meet in the next issue. Prof. Dr. Ali Kemal Ozdemir Editor-in-Chief Cumhuriyet Dental Journal

WOS: 000289389300010, PubMed ID: 21356413, Statement of problem. Rare earth magnets have been used in prosthodontics, but their tendency for corrosion in the oral cavity and insufficient attractive forces limit long-term clinical application. Purpose. The purpose of this study was to evaluate the attractive force of different types of new-generation magnetic attachment systems. Material and methods. The attractive force of the neodymium-iron-boron (Nd-Fe-B) and samarium-cobalt (Sm-Co) magnetic attachment systems, including closed-field (Hilop and Hicorex) and open-field (Dyna and Steco) systems, was measured in a universal testing machine (n=5). The data were statistically evaluated with 1-way ANOVA and post hoc Tukey-Kramer multiple comparison test (alpha=.05). Results. The closed-field systems exhibited greater (P, Cumhuriyet University, This investigation was supported in part by Cumhuriyet University Scientific Research Project (CUBAP).