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Article Citation - WoS: 7Citation - Scopus: 10A FUZZY CONCEPTUAL MODEL FOR MULTIMEDIA DATA WITH A TEXT-BASED AUTOMATIC ANNOTATION SCHEME(World Scientific Publ Co Pte Ltd, 2009) Kucuk, Dilek; Burcuozgur, N.; Yazici, Adnan; Koyuncu, MuratThe size of multimedia data is increasing fast due to the abundance of multimedia applications. Modeling the semantics of the data effectively is crucial for proper management of it. In this paper, we present a fuzzy conceptual data model for multimedia data which is also generic in the sense that it can be adapted to all multimedia domains. The model takes an object-oriented approach and it handles fuzziness at different representation levels where fuzziness is inherent in multimedia applications and should be properly modeled. The proposed model also has the nice feature of representing the structural hierarchy of multimedia data as well as the spatial and temporal relations of the data. The model is applied to the news video domain and implemented as a fuzzy multimedia database system where it turns out to be effective in representing the domain and thereby provides an evidence for the general applicability of the model. The model is accompanied by an automatic multimedia annotation scheme which makes use of information extraction techniques on the corresponding multimedia texts.Article Citation - WoS: 20Citation - Scopus: 24A Bibliometric/Geographic Assessment of 40 Years of Software Engineering Research (1969-2009)(World Scientific Publ Co Pte Ltd, 2013) Garousi, Vahid; Ruhe, GuentherBibliometric rankings are quite common in the field of software engineering. For example, there are a series of ranking repeated every year which identify the top researchers and institutions at the international level in the field. There are also other studies to determine the most cited articles in software engineering journals, the most popular research topics in this area, or identify the top researchers and institutions in regional levels. However, there exists no existing bibliometric quantitative analysis of publications in the area of software engineering (SE), including relative and absolute growth in the number of all SE publications as well as an analysis among countries. This is the main goal and motivation of this article. Besides, this study intends to provide an overall quantitative trend of the software engineering papers, and compare that trend to research output in other areas of science. The bibliometric study reported in this paper is motivated by the fact that understanding the amount of geographical research contributions to the field of software engineering can help identify different countries' level of commitment to support research activities in this area over years. We analyze how the contribution levels of top-ranked countries have changed over the years and how SE compares to other disciplines of engineering and science. Among the most interesting findings of this study are: (1) Over 40 years, in total about 60% of the SE literature has been contributed by only 7% of all countries, (2) the SE research output of different countries does not necessarily correlate with their GDPs, (3) the share of contributions to the SE discipline by the American researchers has declined from 71.43% ( in 1980) to 14.90% ( in 2008), and ( 4) China is the country with the biggest share growth in the number of publications ( from 0.82% of the entire SE publications in 1991 to 13.82% in 2009).Article Citation - WoS: 4Citation - Scopus: 5Electrical Characterization of Bi1.50-x< Varactors(World Scientific Publ Co Pte Ltd, 2014) Qasrawi, A. F.; Abu Muis, Khalil O.; Abu Al Rob, Osama H.; Mergen, A.The electrical properties of yttrium doped bismuth zinc niobium oxide (BZN) pyrochlore ceramics are explored by means of temperature dependent electrical conductivity dielectric constant and capacitance spectra in the frequency range of 0-3 GHz. It is observed that the doped BZN exhibit a conductivity type conversion from intrinsic to extrinsic as the doping content increased from 0.04 to 0.06. The thermal energy bandgap of the intrinsic type is 3.45 eV. The pyrochlore is observed to exhibit a dielectric breakdown at 395 K. In addition, a negative capacitance (NC) spectrum with main resonance peak position of 23.2 MHz is detected. The NC effect is ascribed to the increased polarization and the availability of more free carriers in the device. When the NC signal amplitude is attenuated in the range of 0-20 dBm at 50 MHz and 150 MHz, wide tunability is monitored. Such characteristics of the Y-doped BZN are attractive for using them to cancel the positive parasitic capacitance of electronic circuits. The canceling of parasitic capacitance improves the high frequency performance of filter inductors and reduces the common mode noise of the resonance signal.Article Citation - WoS: 2Citation - Scopus: 1Investigation of Conductivity Characteristics of Zn-In Thin Films(World Scientific Publ Co Pte Ltd, 2020) Gullu, H. H.; Parlak, M.Zn-In-Se thin films were fabricated on the ultrasonically cleaned glass substrates masked with clover-shaped geometry by thermal evaporation of its elemental sources. Temperature-dependent conductivity characteristics of the films were investigated under dark and illuminated conditions. The semiconductor type of the films was found as n-type by thermal probe test. According to the van der Pauw technique, the dark electrical conductivity analyses showed that the variations of conductivity of unannealed and annealed at 300 degrees C samples are in exponential dependence of temperature. These conductivity profiles were found to be dominated by the thermionic emission at high temperature region whereas their behaviors at low temperatures were modeled by hopping theory. On the contrary, as a result of the further annealing temperatures, the surface of the samples showed semi-metallic characteristics with deviating from expected Arrhenius behavior. In addition, the temperature-dependent photoconductivity of the films was analyzed under different illumination intensities and the results were explained by the supra-linear characteristic based on the two-center recombination model.Article Citation - WoS: 10Citation - Scopus: 7Fabrication and Characterization of Tio2 Thin Film for Device Applications(World Scientific Publ Co Pte Ltd, 2019) Hosseini, A.; Gullu, H. H.; Coskun, E.; Parlak, M.; Ercelebi, C.Titanium oxide (TiO2) film was deposited by rectification factor (RF) magnetron sputtering technique on glass substrates and p-Si (111) wafers to fabricate n-TiO2/p-Si heterojunction devices for the investigation of material and device properties, respectively. The structural, surface morphology, optical and electrical properties of TiO(2 )film were characterized by means of scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), UV-visual (UV-Vis) spectral and dark current-voltage (I-V) measurement analyses. The deposited film layer was found to be homogeneous structure with crack-free surface. The bandgap value of TiO2 film was determined as 3.6 eV and transmission was around 65-85% in the spectral range of 320-1100 nm. The conductivity type of the deposited film was determined as n-type by hot probe method. These values make TiO2 film a suitable candidate as the n-type window layer in possible diode applications. TiO2 film was also deposited on p-Si (111) wafer to obtain Al/n-TiO2/p-Si/Al heterojunction device structure. The dark I-V characteristic was studied to determine the possible conduction mechanisms and diode parameters.Article Citation - WoS: 9Absorption and Optical Conduction in Inse/Znse Thin Film Transistors(World Scientific Publ Co Pte Ltd, 2016) Al Garni, S. E.; Qasrawi, A. F.In this work, (n)InSe/(p)ZnSe and (n)InSe/(p)ZnSe/(n)InSe heterojunction thin film transistor (TFT) devices are produced by the thermal evaporation technique. They are characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion X-ray spectroscopy and optical spectroscopy techniques. While the InSe films are found to be amorphous, the ZnSe and InSe/ZnSe films exhibited polycrystalline nature of crystallization. The optical analysis has shown that these devices exhibit a conduction band offsets of 0.47 and valence band offsets of 0.67 and 0.74 eV, respectively. In addition, while the dielectric spectra of the InSe and ZnSe displayed resonance peaks at 416 and 528 THz, the dielectric spectra of InSe/ZnSe and InSe/ZnSe/InSe layers indicated two additional peaks at 305 and 350 THz, respectively. On the other hand, the optical conductivity analysis and modeling in the light of free carrier absorption theory reflected low values of drift mobilities associated with incident alternating electric fields at terahertz frequencies. The drift mobility of the charge carrier particles at femtoseconds scattering times increased as a result of the ZnSe sandwiching between two InSe layers. The valence band offsets, the dielectric resonance at 305 and 350 THz and the optical conductivity values nominate TFT devices for use in optoelectronics.Article Citation - WoS: 3Citation - Scopus: 4Friction and Wear Behavior of Selected Dental Ceramics(World Scientific Publ Co Pte Ltd, 2009) Park, Jongee; Pekkan, Gurel; Ozturk, AbdullahThe purpose of this study was to determine the friction coefficients and wear rates of six commercially available dental ceramics including IPS Empress 2 (E2), Cergo Pressable Ceramic (CPC), Cercon Ceram (CCS) and Super porcelain EX-3 (SPE). Bovine enamel (BE) was also tested as a reference material for comparison purposes. Samples of the dental ceramics were prepared according to the instructions described by the manufacturers in disk-shape with nominal dimensions of 12 mm x 2 mm. The wear tests were performed by means of a pin-on-disk type tribometer. The friction coefficients and specific wear rates of the materials were determined at a load of 10 N and rotating speed of 0.25 cm/s without lubrication. Surface morphology of the wear tracks was examined using a scanning electron microscope. Statistical analyses were made using one-way ANOVA and Turkey's HSD (P < 0.05).Article Citation - WoS: 4Citation - Scopus: 4Bioactivity of Apatite-Wollastonite Glass-Ceramics Produced by Melting Casting(World Scientific Publ Co Pte Ltd, 2013) Park, Jongee; Ozturk, AbdullahGlass-ceramics containing only apatite and wollastonite crystals were produced in the system MgO-CaO-SiO2-P2O5-F by the melt casting process. The bioactivity of the glass-ceramics was determined by immersing the glass-ceramics in a simulated body fluid (SBF) and by assessing the resulting apatite formation on the free surface after various immersion durations. A 12-mu m-thick apatite layer formed on the surface of the glass-ceramic containing only apatite crystals after 20 days immersion in SBF. However, the thickness of the apatite layer formed on the surface of the glass-ceramic containing apatite and wollastonite crystals was 1 mu m. Results have shown that the bioactivity of glass-ceramic depends strongly on the type of crystal(s) developed during the glass-ceramic process and their proportion in the glassy matrix.Article Citation - WoS: 4Citation - Scopus: 4Electrical Conductivity and Capacitance Spectra of Bi1.37sm0.13< Pyrochlore Ceramic in the Range of 0-3 Ghz(World Scientific Publ Co Pte Ltd, 2014) Qasrawi, A. F.; Bzour, Faten M.; Nazzal, Eman O.; Mergen, A.In this work, the electrical properties of samarium-doped bismuth niobium zinc oxide (Sm-doped BZN) pyrochlore ceramics are investigated by means of temperature dependent electrical conductivity and capacitance spectroscopy in the frequency range of 0-3 GHz. It was observed that the novel dielectric Sm-BZN ceramic exhibits a temperature and electric field dependent dielectric breakdown. When measured at 300 K, the breakdown electric field is 1.12 kV/cm and when heated the breakdown temperature is similar to 420 K. The pyrochlore is thermally active above 440K with conductivity activation energy of 1.37 eV. In addition, the room temperature capacitance spectra reflected a resonance-antiresonance switching property at 53MHz when subjected to an AC signal of low power of 5 dBm. Furthermore, when the Sm-BZN ceramics are used as microwave cavity and tested in the frequency range of 1.0-3.0 GHz, the cavity behaves as low pass filter with wide tunability up to a frequency of 1.91 GHz. At this frequency it behaves as a band rejection filter that blocks waves of 1.91 GHz and 2.57 GHz frequencies. These properties of the Sm-doped BZN are promising as they indicate the usability of the ceramics in digital electronic circuits as resonant microwave cavities suitable for the production of low pass/rejection band filters.Article Citation - WoS: 6Citation - Scopus: 10Beyond Rouge: a Comprehensive Evaluation Metric for Abstractive Summarization Leveraging Similarity, Entailment, and Acceptability(World Scientific Publ Co Pte Ltd, 2024) Briman, Mohammed Khalid Hilmi; Yıldız, Beytullah; Yildiz, Beytullah; Yıldız, BeytullahA vast amount of textual information on the internet has amplified the importance of text summarization models. Abstractive summarization generates original words and sentences that may not exist in the source document to be summarized. Such abstractive models may suffer from shortcomings such as linguistic acceptability and hallucinations. Recall-Oriented Understudy for Gisting Evaluation (ROUGE) is a metric commonly used to evaluate abstractive summarization models. However, due to its n-gram-based approach, it ignores several critical linguistic aspects. In this work, we propose Similarity, Entailment, and Acceptability Score (SEAScore), an automatic evaluation metric for evaluating abstractive text summarization models using the power of state-of-the-art pre-trained language models. SEAScore comprises three language models (LMs) that extract meaningful linguistic features from candidate and reference summaries and a weighted sum aggregator that computes an evaluation score. Experimental results show that our LM-based SEAScore metric correlates better with human judgment than standard evaluation metrics such as ROUGE-N and BERTScore.
