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Thermal imaging at the infrared wavelength regime has long been applied to different areas such as agriculture and defense industries. Metasurfaces, 2D engineered ultra-thin structures, have attracted much attention due to their compact size, superior performance, and different functionalities at optical frequencies. This work details the design and fabrication of high transmission metalenses operating at the long-wave infrared (LWIR) spectrum. We minimize the reflection losses through anti-reflection coating (ARC) while maintaining the full wavefront control at the central wavelength 9.07 µm. Our unit cell structure provides an average transmission of 97.5%. We experimentally verify our results and show that the fabricated metalenses perform diffraction-limited imaging at the design wavelength.

SUMMARY: The aims of this study were to determine the prevalence, type, and clinical features of nosocomial infections (NIs), their etiological distribution, and the antibiotic resistance patterns of causative organisms in the general pediatric wards of a hospital in Turkey over a 3-year period. The Hospital Infection Control Committee NI surveillance reports were used as a database. NIs were detected in 171 (2.25z) of the 7,594 hospitalized patients. Some of these patients experienced more than 1 episode, and thus, the total NI episodes were 229. Patients' age varied from 1 to 144 months (mean± standard deviation, 14.5± 23.6 months). The NI rate was 3.02z, and the NI density was 3.17/1,000 patient days. The most frequent NIs were lower respiratory system infections, blood stream infections, and urinary tract infections. Gram-negative organisms were the most frequently isolated agents. Of the 171 patients with NIs, 47 (27.5z )d ied. Nosocomial infections (NIs) are the major causes of prolonged hospital stays, increased costs, the increased resistance of organisms to antimicrobials, and mortality in hospitalized adults and children. NIs in pediatric and adult patients differ with respect to the sites of infection and the types of pathogens. In addition, NIs differ by country, region, hospital, and type of units, such as wards or intensive care units (1). There exist many reports on epidemiology, risk factors, and preventive measures for adult NIs. However, studies that focus on the pediatric population, particularly in developing countries, are limited. For this reason, we investigated the epidemiological, microbiological, and clinical features of NIs in the general wards of ap ediatric hospital that does not have a pediatric intensive care unit (PICU) facility.

Bu tezde, koordinat ölçme cihazlarında yapılan ölçümlerin belirsizliklerianaliz edilmis ve bu belirsizliklerin benzetimine imkan veren bir simulasyonyazılımı tasarlanmıstır. Söz konusu analize cihazın ölçüm isleminin veyapısının incelenmesi ile baslanmıstır Sonrasında ölçümü etkileyecek hatakaynakları tespit edilmis, sistematik hataların bir bölümü modellenmis veayrılmıstır. Bu sayede ölçüm belirsizligi sistematik olan kinematik, geometrikve ısıl hatalardan ayrılmıs olmustur. Uygulanan kinematik ve geometrik hatamodeli cihazın yapısına baglıdır. Ayrıca cihazın yapısına baglı olmayan ortakbir model olusturulmus ve modelde lazer hata verileri kullanılarak makinahacminin hata haritası çıkarılmıstır. Sonrasında ise olusturulan iki model,sonuçların farkına ve oranına bakılarak karsılastırılmıstır.Tanımlanan sistematik hataların telafi edilmesi analiz için geriye ölçümbelirsizligini bırakmıstır. Ölçüm belirsizligi telafi edilemeyen sistematik verasgele hatalardan kaynaklanmaktadır. Bu tezin diger bir amacıda bahsedilenbelirsizligin farklı yöntemler kullanılarak miktarlanması ve bu yöntemlerinbasarısının incelenmesidir. Bu kapsamda belirsizlik bütçeleme, karsılastırma,deney tasarlanarak istatistik ile degerlendirme ve benzesim yöntemleriincelenmis ve mevcut bir cihaza uygulanmıstır. Bununla birlikte, tekrarlananölçümler gerektirmeden daire, düzlem ve küre ölçümleri gibi ise özel ölçümbelirsizliklerini benzestirmek için sanal koordinat ölçme cihazı yazılımıtasarlamıstır. Son olarak performansı cihazın matematiksel modellemesi baglıolarak degisen bu yazılım gerçek ölçümler ile karsılastırılarak test edilmistir.Anahtar Kelimeler: Dogruluk Mühendisligi, Boyutsal Ölçüm Belirsizligi,Koordinat Ölçme Cihazı, Kinematik ve Geometrik Hata Modellemesi,Simülasyon In this thesis, the measurement uncertainty of Coordinate Measuring Machine(CMM) is analysed and software is designed to simulate this. Analysis begins withthe inspection of the measurement process and structure of the CMMs. After that,error sources are defined with respect to their effects on the measurement and then anerror model is constructed to compensate these effects. In other words, systematicpart of geometric, kinematic and thermal errors are compensated with errormodelling. Kinematic and geometric error model is specific for the structure ofCMM under inspection. Also, a common orthogonal kinematic model is formed andwith using the laser error data of the CMM and error maps of the machine volume isobtained. Afterwards, the models are compared with each other by taking thedifference and ratio.The definition and compensation of the systematic errors leave the uncertaintyof measurements for analysing. Measurement uncertainty consists of theuncompensated systematic errors and random errors. The other aim of the thesis is toquantify these uncertainties with using the different methods and to inspect thesuccess of these methods. Uncertainty budgeting, comparison, statistical evaluationby designing an experiments and simulation methods are examined and applied tothe CMM under inspection. In addition, Virtual CMM software is designed tosimulate the task specific measurement uncertainty of circle, sphere and planewithout using the repeated measurements.Finally, the performance of the software, highly depending on themathematical modelling of machine volume, is tested by using actual measurements.Keywords: Precision Engineering, Dimensional Measurement Uncertainty,Coordinate Measuring Machine, Kinematic and Geometric Error Modelling,Simulation. 173

ÖZET Bu çalışmanın temel amacı Bilecik ilinde hava kalitesine etkisi olan tüm kirletici kaynakların belirlenmesi ve bunların etkilerine dayanarak bir emisyon envanteri ve modelleme çalışmasının hazırlanmasıdır. Bu tez kapsamında, Bilecik ilinin hava kirliliği envanteri kükürt dioksit, partikül madde, karbon monoksit, azotoksitler ve hidrokarbonlar için çıkarılmış ve Gauss Dispersiyon modeli ve ATDL (Atmospheric Turbulance and Diffusion Laboratory) dispersiyon-modelleme yöntemi kullanılarak Bilecik ilindeki kükürt dioksit ve partikül madde konsantrasyon dağılımları tespit edilmiştir. Günümüze kadar yapılmış mevcut hava kalitesi seviyeleri hakkında bilgiler toplanmış ve bunların kaynaklan araştırılmıştır. Sanayi bölgesinden, evsel ısınmadan ve trafikten kaynaklanan kirletici emisyon miktarları, sanayi tesislerinin emisyon raporları ve Amerikan EPA emisyon faktörleri kullanılarak hesaplanmıştır. Bu hesaplamalara göre Bilecik ilinde kükürt dioksit emisyonlarının %47,5'i sanayiden, %50,4'ü evsel ısınmadan ve %2,1'i trafikten, partikül madde emisyonlarının %5,8'i sanayiden, %89,5'i evsel ısınmadan ve %4,7'si trafikten, karbon monoksit emisyonlarının %4,6'sı sanayiden, %64'ü evsel ısınmadan ve %31,4'ü trafikten, azot oksit emisyonlarının %19,9'u sanayiden, %53,5'i evsel ısınmadan ve %26,6'sı trafikten, hidrokarbon emisyonlarının %0,4'ü sanayiden, %13,3'ü evsel ısınmadan ve %86,3'ü trafikten kaynaklanmaktadır. Bilecik ili 2*2 km'lik grid ve yüksekliği 1000 m olan bir kutu olarak düşünülmüş, buradan bulunan kükürt dioksit ve partikül madde emisyon yükleri ve meteorolojik veriler kullanılarak bölgede modelleme çalışması yapılmıştır. Model kullanılarak elde edilen değerler ve gerçek ölçümler kıyaslandığında yüksek korelasyon sağlandığı görülmüştür. Anahtar Kelimeler: Emisyon envanteri, Gauss Dispersiyon Modeli, ATDL, SO2, PM. ıx ABSTRACT The main objects of this study are to determine all the pollution sources which affect air quality in Bilecik and to prepare emission inventory and modeling as regarding of the results. In this study, emission inventory of Bilecik was created for criteria pollutants including sulfur dioxide (SO2), particulate matter (PM), carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC). Also distribution of sulfur dioxide and particulate matter concentrations were determined using Gaussian Dispersion Model and Atmospheric Turbulence and Diffusion Laboratory (ATDL) Model in Bilecik. Up to date information about existing air quality levels in Bilecik was collected and contaminative sources were searched. The amounts of emissions originated from industrial region, domestic fuel burning and traffic were calculated using the emission reports of the industrial plants and emission factors of the US EPA. According to these calculations, 47,5% of total sulfur dioxide emissions came from industry, 50,4% from combustion for domestic heating, and 2,1% from traffic; 5,8% of total particulate matter emissions came from industry, 89,5% from combustion for domestic heating, and 4,7% from traffic; 4,6% of total carbon monoxide emissions came from industry, 64% from combustion for domestic heating, and 31,4% from traffic; 19,9% of total nitrogen oxides emissions came from industry, 53,5% from combustion for domestic heating, and 26,6% from traffic; 0,4% of total hydrocarbon emissions came from industry, 13,3% from combustion for domestic heating, and 86,3% from traffic; Bilecik's atmosphere is considered to be a 1000 m height box on the surface of 2*2 km grid. Modeling study was done for sulfur dioxide and particulate matter emissions obtained by using the box model with the aid of meteorological data. As a result, high correlations between the values obtained from modeling and real measurement were found. Keywords: Emission inventory, Gaussian Dispersion Model, ATDL, SO2, PM 84

Objective: to compare the effectiveness of different mask types in limiting the dispersal of coughed air. Method: the Schlieren method with a single curved mirror was used in this study. Coughed air has a slightly higher temperature than ambient air, which generates a refractive index gradient. A curved mirror with a radius of curvature of 10 m and a diameter of 60 cm was used. The spread of the cough wavefront was investigated among five subjects wearing: (1) no mask; (2) a single surgical mask; (3) a double surgical mask; (4) a cloth mask; (5) a valveless N95 mask; and (6) a valved N95 mask. Results: all mask types reduced the size of the contaminated region significantly. The percentage reduction in the cross-sectional area of the contaminated region for the same mask types on different subjects revealed by normalized data suggests that the fit of a mask plays an important role. Conclusions: no significant difference in the spread of coughed air was found between the use of a single surgical mask or a double surgical mask. Cloth masks may be effective, depending on the quality of the cloth. Valved N95 masks exclusively protect the user. The fit of a mask is an important factor to minimize the contaminated region., 2232 International Fellowship for Outstanding Researchers Program; Scientific and Technological Research Council of Turkey (TÜBİTAK)