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All-optical information-processing capacity of diffractive surfaces

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Light(Science & Applications) 2021年第2期10卷 217-233页

作者： Onur Kulce Deniz Mengu Yair Rivenson a.dogan ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos AngelesCA 90095USA California NanoSystems Institute University of CaliforniaLos AngelesCA 90095USA

The precise engineering of materials and surfaces has been at the heart of some of the recent advances in optics and *** advances related to the engineering of materials with new functionalities have also opened up exciting avenues for designing trainable surfaces that can perform computation and machine-learning tasks through light-matter interactions and ***,we analyze the information-processing capacity of coherent optical networks formed by diffractive surfaces that are trained to perform an all-optical computational task between a given input and output *** show that the dimensionality of the all-optical solution space covering the complex-valued transformations between the input and output fields-of-view is linearly proportional to the number of diffractive surfaces within the optical network,up to a limit that is dictated by the extent of the input and output *** diffractive networks that are composed of larger numbers of trainable surfaces can cover a higher-dimensional subspace of the complex-valued linear transformations between a larger input field-of-view and a larger output field-of-view and exhibit depth advantages in terms of their statistical inference,learning,and generalization capabilities for different image classification tasks when compared with a single trainable diffractive *** analyses and conclusions are broadly applicable to various forms of diffractive surfaces,including,e.g.,plasmomc and/or dielectric-based metasurfaces and flat optics,which can be used to form all-optical processors.

关键词： surface. valued optics

Structural and superconducting properties in Y_(0.6)Gd_(0.4)Ba_2(Nb)Cu_3O_(7-y) cuprates doped with niobium

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Journal of Rare Earths 2012年第3期30卷 241-244页

作者： M. Yilmaz O. dogan A. K. Education Faculty Department of Physics Konya University

Polycrystalline YBa2Cu3O7-y （YBCO） and Y0.6Gd0.4Ba2-xNbxCu3O7-y （YGBNCO） compounds with 0≤x≤0.225 were synthesized using standard solid state reaction technique. The structure for all samples was characterized by X-ray difference （XRD） and scanning electron microscopy （SEM）. The transport properties were measured by the （FPP） method in the temperature range from 70 to 130 K. As the Nb content in the samples increased, a diffused phase indicating a niobium perovskite phase and a small amount of unidentified phase appeared. With the increase of Nb content, the superconducting transition temperature Tconset increased slowly with x≤0.125, and then it remained unchanged or slowly decreased with 0.125≤x≤0.225. It could be found that there was a slow decrease of zero-resistance temperature, Tcoffset, with the increase of Nb content. The larger transition width might result from the YBa2NbO6 phase, impurity and unidentified phases of the sample due to the Nb doping.

关键词： Y0.6Gd0.4Ba2Cu3O7-y cuprates Gd and Nb co-doping structural and superconducting properties rare earths

Effects of Different Geographical Aspects and Ontogenetic Variability on Total Hypericin Content of Hypericum triquetrifolium Turra. and Hypericum scabrum L.

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Phyton-International Journal of Experimental Botany 2020年第4期89卷 1091-1099页

作者： Emine Aslan dogan Arslan Field Crops Department Faculty of AgricultureSiirt UniversitySiirt56000Turkey

The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium *** Hypericum scabrum *** which are naturally distributed in the flora of Siirt province,*** contents of Hypericum species grown in different geographical aspects(North,South,East,and West),and it was measured at different harvest times(full bloom-ing and post blooming period).In the current study,it has been determined that total hypericin content varies considerably according to aspects,plant developmental stages(ontogenetic variance),and *** to species x aspect interaction,the highest total hypericin content was recorded from the west aspect(3.13 mg/g)in Hypericum triquetrifolium,while,the lowest hypericin content was also obtained from the west aspect(1.22 mg/g)in Hypericum *** the highest total hypericin content was analyzed according to aspect x species x harvest time interaction,the highest total hypericin content was produced from Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g,while the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/*** species x harvest time interaction,the highest total hypericin content was obtained from the full bloom(3.10 mg/g)harvest in Hypericum triquetrifolium,while the lowest hypericin was obtained from the full bloom(1.26 mg/g)harvest in Hypericum *** data suggest that the aver-age total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and 1.28 mg/g in Hypericum scabrum.

关键词： Hypericum triquetrifolium Hypericum scabrum aspect hypericin

SCANNING LASER POLARIMETRIC FOL-LOW-UP OF TURKISH PATIENTS WITH OCULAR HYPERTENSION

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国际眼科杂志 2003年第1期3卷 30-31页

作者： B.Bozkurt M.Irkec a.dogan M.Orhan E.Karaagaoglu Hacettepe University TurkeyHacettepe University TurkeyHacettepe University TurkeyHacettepe University TurkeyHacettepe University Turkey

Purpose: To detect the progression of glaucomatous damage in the retinal nerve fiber layer (RNFL) in ocular hypertensive (OHT) patients with scanning laser polarimetry. Materials and methods: 15 females, 5 males whose ages range between 36 and 75 years (mean age: 54.15 ±12.11 years) were included in the OHT study group. Patients with intraocular pressure (IOP)

关键词：土耳其人高眼压扫描激光旋光法青光眼视网膜神经纤维层

A clinical and epidemiological study on spider bites in Turkey

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Asian Pacific Journal of Tropical Medicine 2011年第2期4卷 159-162页

作者： Yildirim Cesaretli ozcan Ozkan Refik Saydam Public Health Agency 06100AnkaraTurkey

Objective:To classify and characterize spider bites among inquiries to the National Poison Information Center(NPIC) between 1995 and 2004,in terms of the epidemiology and clinical ***:Clinical and epidemiological data were obtained from the NPIC’s patient *** following information was recorded for each spider bite:demographics, circumstances of the bite,and local and systemic ***:A total of 82 cases were *** accidents were mostly seen during *** gender distribution was 59.76% male,37.20%female,and 2.44%unknown and the 20-29 age group presented more spider bites. Most of the cases were in the Central Anatolia,Marmara,Mediterranean,and Black Sea regions. Local symptoms were observed in 60.87%of the cases,including local pain,edema,redness, itching,debris,burning,and *** symptoms were observed such as nausea, vomiting,abdominal pain,lethargy,anxiety,weakness,somnolence,dyspnea,hypertension, hypotension,and ***:In conclusion,these findings emphasize the presence of medically important spider species in *** patients and especially pediatric patients should be admitted to the *** of spider species may be considered a useful clinical and epidemiological tool in determining the incidence and risk of spider bites.

关键词： Spider bite Envenomation Clinical features Epidemiology Turkey

Hydrodynamic Conditions in Front of a Vertical Wall with an Overhanging Horizontal Cantilever Slab

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Journal of Ocean University of China 2017年第6期16卷 978-990页

作者： KISACIK dogan OZYURT Gulizar TROCH Peter Institute of Marine Sciences and Technology Dokuz Eylül University Department of Civil Engineering Middle East Technical University Department of Civil Engineering Ghent University

Transforming wave heights from offshore to the shoreline is the first step of any coastal engineering work. Wave breaking is analyzed to understand hydrodynamic conditions. For vertical breakwaters and sea walls, wave reflection is an important process that affects the determination of the wave height. Many of the design formulas presented in the literature depend on empirical studies based on the structures tested. In this study, the hydrodynamic conditions in front of a vertical wall with an overhanging horizontal cantilever slab with a foreshore slope of 1/20 are determined experimentally under regular wave conditions to assess the applicability of the formulas of Goda(2000) for predicting the nearshore wave height and breaker index equation(Goda, 2010). The selection of wave measurements used to determine the design wave height, the reflection coefficients, and wave breaking is also analyzed, and the reflection equations are derived from the dataset covering different breaker types. Small-scale tests show that the incident wave height is a good representative of the design wave height and that the values predicted by Goda are in good agreement with actual measurements. However, the predicted Hmax values are overestimated. In addition, the inception of the wave breaking point is postponed because of the reflection and/or turbulence left over from preceding waves, which is an effect of the vertical wall. At higher water levels, the effect of the vertical wall on the inception point becomes more significant.

关键词： wave breaking wave reflection wave shoaling vertical structure horizontal cantilever slab

SYNTHESIS AND CHARACTERIZATION OF AN ACRYLATE POLYMER CONTAINING CHLORINE-1,3-DIOXALANE GROUPS IN SIDE CHAINS

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Chinese Journal of Polymer Science 2012年第5期30卷 642-651页

作者： Zulfiye Ilter Ferhat Alhanli Fatih dogan Ismet Kaya Firat University Faculty of Science and ArtsDepartment of ChemistryElazigTurkey Canakkale Onsekiz Mart University Faculty of EducationSecondary Science and Mathematics Education 17100CanakkaleTurkey Canakkale Onsekiz Mart University Department of Chemistry17020CanakkaleTurkey

Poly[2-（4-chlorophenyl）-l,3-dioxolan-4-yl]methyl acrylate, poly（CPhDMA）, was synthesized with radical polymerization process using 2,2＇-azobisisobutyronitrile as radical initiator in 1,4-dioxane at 60℃. The structure of poly（CPhDMA） was confirmed by means of UV-Vis, FT-IR, 1H-NMR, and 13C-NMR spectral techniques. The molecular weight distribution values of the polymer were determined with gel permeation chromatography （GPC）. The number-average molecular weight （Mn）, weight-average molecular weight （Mw） and polydispersity index （PDI） values of poly（CPhDMA） were determined to be 10300, 21600 and 2.097, respectively. The thermal degradation kinetics of the polymer was investigated by using TG/DTG-DTA and DSC analyses at different heating rates in dynamic nitrogen atmosphere. The apparent activation energy values obtained by Flynn-Wall-Ozawa and Friedman methods were found to be 91.68 and 85.23 kJ mo1-1, respectively, for thermal decomposition of poly（CPhDMA）. Also, the thermal degradation activation energy value of poly（CPhDMA） was calculated by using the Kissinger method based on the DTG, DTA and DSC data. Then the mechanism function of it was determined by master plots method. Finally, electrical and optical properties of poly（CPhDMA） were determined by four-point probe and UV-Vis techniques, respectively.

关键词： Synthesis of acrylate polymer Thermal degradation Kinetic parameters.

Assessing vulnerability of a forest ecosystem to climate change and variability in the western Mediterranean sub-region of Turkey

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Journal of Forestry Research 2018年第3期29卷 704-720页

作者： Orkan ozcan Nebiye Musaoglu Murat Tuükes Eurasia Institute of Earth Sciences Istanbul Technical UniversityMaslak34469 IstanbulTurkey Geomatics Engineering Department Civil Engineering FacultyIstanbul Technical UniversityMaslak34469 IstanbulTurkey Center for Climate Change and Policy Studies Bogazici UniversityBebek34342 IstanbulTurkey

Climate change is a real, pressing and significant global problem. The concept of ‘climate change vulnerability’ helps us to better comprehend the cause/effect relationships behind climate change and its impact on human societies, socioeconomic sectors, and physiographical and ecological systems. In this study, multifactorial spatial modelling evaluated the vulnerability of a Mediterranean forest ecosystem to climate change and variability with regard to land degradation. This produced data and developed tools to support better decision-making and management. As a result, the geographical distribution of Environmental Vulnerability Areas(EVAs) of the forest ecosystem is the estimated Environmental Vulnerability Index(EVI) values. These revealed that, at current levels of environmental degradation, physical, geographical, policy enforcement, and socioeconomic conditions, the area with a ‘‘very low’’ degree of vulnerability covered mainly the town, its surrounding settlements and agricultural lands found principally over the low, flat travertine plateau and the plains to the east and southeast of the district. The spatial magnitude of the EVAs of the forest ecosystem under current environmental degradation was also determined. This revealed that the EVAs classed as ‘‘very low’’accounted for 21% of the area of the forest ecosystem,those classed as ‘‘low’’ for 36%, those classed as ‘‘medium’’ for 20%, and those classed as ‘‘high’’ for 24%.

关键词： Mediterranean climate Forest ecosystem Land degradation Vulnerability analysis

Recurrent neural network-based volumetric fluorescence microscopy

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Light(Science & Applications) 2021年第4期10卷 620-635页

作者： Luzhe Huang Hanlong Chen Yilin Luo Yair Rivenson a.dogan ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos AngelesCA 90095USA California Nano Systems Institute(CNSI) University of CaliforniaLos AngelesCA 90095USA David Geffen School of Medicine University of CaliforniaLos AngelesCA 90095USA

Volumetric imaging of samples using fluorescence microscopy plays an important role in various fields including physical,medical and life *** we report a deep learning-based volumetric image inference framework that uses 2D images that are sparsely captured by a standard wide-field fluorescence microscope at arbitrary axial positions within the sample *** a recurrent convolutional neural network,which we term as Recurrent-MZ,2D fluorescence information from a few axial planes within the sample is explicitly incorporated to digitally reconstruct the sample volume over an extended *** experiments on *** and nanobead samples,Recurrent-MZ is demonstrated to significantly increase the depth-of-field of a 63×/1.4NA objective lens,also providing a 30-fold reduction in the number of axial scans required to image the same sample *** further illustrated the generalization of this recurrent network for 3D imaging by showing its resilience to varying imaging conditions,including e.g.,different sequences of input images,covering various axial permutations and unknown axial positioning *** also demonstrated wide-field to confocal cross-modality image transformations using Recurrent-MZ framework and performed 3D image reconstruction of a sample using a few wide-field 2D fluorescence images as input,matching confocal microscopy images of the same sample ***-MZ demonstrates the first application of recurrent neural networks in microscopic image reconstruction and provides a flexible and rapid volumetric imaging framework,overcoming the limitations of current 3D scanning microscopy tools.

关键词： neural network networks