Mathematical And Computational Methods For Freeform Optical Shape Description

Slow-servo single-point diamond turning as well as advances in computer controlled small lap polishing enable the fabrication of freeform optics, specifically, optical surfaces for imaging applications that are not rotationally symmetric. Freeform optical elements will have a profound importance in the future of optical technology. Orthogonal polynomials added onto conic sections have been extensively used to describe optical surface shapes. The optical testing industry has chosen to represent the departure of a wavefront under test from a reference sphere in terms of orthogonal φ-polynomials, specifically Zernike polynomials. Various forms of polynomials for describing freeform optical surfaces may be considered, however, both in optical design and in support of fabrication. More recently, radial basis functions were also investigated for optical shape description. In the application of orthogonal φ-polynomials to optical freeform shape description, there are important limitations, such as the number of terms required as well as edge-ringing and ill-conditioning in representing the surface with the accuracy demanded by most stringent optics applications. The first part of this dissertation focuses upon describing freeform optical surfaces with φ-polynomials and shows their limitations when including higher orders together with possible remedies. We show that a possible remedy is to use edge-clusteredfitting grids. Provided different grid types, we furthermore compared the efficacy of using different types of φ-polynomials, namely Zernike and gradient orthogonal Q-polynomials. In the second part of this thesis, a local, efficient and accurate hybrid method is developed in order to greatly reduce the order of polynomial terms required to achieve higher level of accuracy in freeform shape description that were shown to require thousands of terms including many higher order terms under prior art. This comes at the expense of multiple sub-apertures, and as such iv computational methods may leverage parallel processing. This new method combines the assets of both radial basis functions and orthogonal phi-polynomials for freeform shape description and is uniquely applicable across any aperture shape due to its locality and stitching principles. Finally in this thesis, in order to comprehend the possible advantages of parallel computing for optical surface descriptions, the benefits of making an effective use of impressive computational power offered by multi-core platforms for the computation of φ-polynomials are investigated. The φ-polynomials, specifically Zernike and gradient orthogonal Q-polynomials, are implemented with a set of recurrence based parallel algorithms on Graphics Processing Units (GPUs). The results show that more than an order of magnitude speedup is possible in the computation of φ-polynomials over a sequential implementation if the recurrence based parallel algorithms are adopted

Modeling Aerospace Ground Equipment (AGE) Usage in Military Environments

There is a wide array of multi-attribute decision analysis methods and associated sensitivity analysis procedures in the literature. However, there is no detailed discussion of sensitivity analysis methods solely relating to additive hierarchical value models. The currently available methodology in the literature is unsophisticated and can be hard to implement into complex models. The methodology proposed in this research builds mathematical foundations for a robust sensitivity analysis approach and extends the current methodology to a more powerful form. The new methodology is easy to implement into complex hierarchical value models and gives flexible and dynamic capabilities to decision makers during sensitivity analysis. The mathematical notation is provided in this study along with applied examples to demonstrate this methodology. Global and local sensitivity analysis are considered and implemented using the proposed robust technique. This research provides consistency and a common standard for the decision analysis community for sensitivity analysis of multi-attribute deterministic hierarchical value models

Flood control with retarding basin type reservoirs in Meramec Basin, Missouri

When rainfall occurs that provides more runoff than can be carried within the normal channels of existing streams a flood results. The excess water overflows the valley lands, invades developed areas, and causes destruction of property or, in extreme cases, loss of human life...Many structures are built to control water: Waterways of proper depth and width provide arteries of transportation; water controlled and discharged through water-wheels provides power; water may be caught in storage basins and distributed for irrigation or water supply; and water that is an actual or potential source of damage or danger to property or to human life may be controlled to prevent floods. When this control of water involves only the prevention of flood damage it is termed flood control . The Meramec River is the first major tributary entering the Mississippi River on the right bank below the mouth of the Missouri River. The watershed area, comprising about 3,955 square miles, lies in the eastern central part of the State of Missouri...The object of this study is to recommend ways and means of regulating the streams of the Meramec Basin and is not concerned with the effects of the regulated waters on the Mississippi river. A comparison is made on the valuable farm and industrial downstream lands saved from inundation against the upstream areas flooded by the backwaters of reservoirs --Introduction, page 1-2

Acceleration of computation of phi-polynomials

The benefits of making an effective use of impressive computational power offered by multi-core platforms are investigated for the computation of phi-polynomials used in the description of freeform surfaces. Specifically, we devise parallel algorithms based upon the recurrence relations of both Zernike polynomials and gradient orthogonal Q-polynomials and implement these parallel algorithms on Graphical Processing Units (GPUs) respectively. The results show that more than an order of magnitude improvement is achieved in computational time over a sequential implementation if these recurrence-based parallel algorithms are adopted in the computation of the phi-polynomials

CORTEN ÇELİĞİN HEYKELDEKİ AVANTAJLARI VE PAS ESTETİĞİ

CORTEN ÇELİĞİN HEYKELDEKİ AVANTAJLARI VE PAS ESTETİĞİ İlhan KAYA Atatürk Üniversitesi Heykel Bölümü Erzurum, Türkiye [email protected] https://orcid.org/0000-0002-3627-4818 Atıf Kaya, İ. (2023). Corten Çeliğin Heykeldeki Avantajlari Ve Pas Estetiği. The Turkish Online Journal of Design Art and Communication, 14(2), x………………... ÖZ Corten çeliği 1960’lı yıllarda U.S Steel tarafından geliştirilmiş bir çelik türüdür. Corten farklı atmosferik koşullarda kullanılabilir olması, bakım ihtiyacının daha az olması ve doğal görünümlü bir malzeme olma yönü ile de diğer çeliklere göre avantajlıdır. Zaman geçtikçe dış etkenlere bağlı olarak renginde değişimler olduğu için kendi içinde yaşayan bir malzemedir. Corten çelik korozyona karşı dirençli olması ve estetik görünümlü olması nedeniyle yapı elemanı olarak mimari alanda oldukça yaygın kullanılmaktadır. Heykel sanatında da kullanılan corten çelik paslı yüzeyindeki farklı organik renk tonları ile estetik açıdan etkileyici bir görünüme sahiptir. Corten, heykel sanatçılarının bu özelliklerinden dolayı avantajlı gördükleri bir malzemedir. Paslı yüzeyinin boya, zımpara veya kaplama gibi farklı bir malzeme ve uygulamaya gerek duymadan kullanılabilir olması bu avantajı sağlamaktadır. Corten, ilk kullanım aşamasında sarımsı bir görünüm sergiler ve daha sonra çevre şartlarına göre zaman içinde kahverengiye dönüşür. Ardından, renk değişimi devam eder ve siyahımsı koyu bir kahverengiye dönüşür. Corten çeliğin etkilendiği bazı dezavantajlı yönleri de vardır. Bunlar; hava koşullarının etkisi ile kirlenme, çeşitli asitler, gaz halindeki kirleticiler, kuş pislikleri, nem ve vandalizm gibi durumlardır. Heykel alanında corten çeliği; Richard Serra, Antony Gormley, Eduardo Chillida, Barnett Newman, Donald Judd ve Horst Antes gibi sanatçılar yoğun olarak kullanmaktadırlar. Anahtar Kelimeler: Corten Çelik, Pas, Estetik, Heykel, İzdas Kongre Ulusal Ve Uluslar Arası Katılımlı & Hakemli Spesifik Kongreler Platformu 5. Uluslar Arası Haliç Multidisipliner Bilimsel Araştırmalar Kongresinde Bildiri olarak sunulmuştur. 15-16 Ocak 2023, İstanbul

Comparative assessment of freeform polynomials as optical surface descriptions

Slow-servo single-point diamond turning as well as advances in computer controlled small lap polishing enables the fabrication of freeform optics, or more specifically, optical surfaces for imaging applications that are not rotationally symmetric. Various forms of polynomials for describing freeform optical surfaces exist in optical design and to support fabrication. A popular method is to add orthogonal polynomials onto a conic section. In this paper, recently introduced gradient-orthogonal polynomials are investigated in a comparative manner with the widely known Zernike polynomials. In order to achieve numerical robustness when higher-order polynomials are required to describe freeform surfaces, recurrence relations are a key enabler. Results in this paper establish the equivalence of both polynomial sets in accurately describing freeform surfaces under stringent conditions. Quantifying the accuracy of these two freeform surface descriptions is a critical step in the future application of these tools in both advanced optical system design and optical fabrication

ANTIMICROBIAL ACTIVITY OF VARIOUS EXTRACTS OF OCIMUM BASILICUM L. AND OBSERVATION OF THE INHIBITION EFFECT ON BACTERIAL CELLS BY USE OF SCANNING ELECTRON MICROSCOPY

The antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of Ocimum basilicum L. were studied. These extracts were tested in vitro against 10 bacteria and 4 yeasts strains by the disc diffusion method. The results indicated that the methanol extracts of O. basilucum exhibited the antimicrobial activity against tested microorganisms. While the chloroform and acetone extracts had no effect, the methanol extracts showed inhibition zones against strains of Pseudomonas aeruginosa, Shigella sp., Listeria monocytogenes, Staphylococcus aureus and two different strains of Escherichia coli. The cells of microorganisms, which were treated and untreated with plant extracts, were observed by using the scanning electron microscope. It was observed that the treated cells were damaged

Determining of Relationship Between Weed Seedbank in Soil and Weed Flora in Potato Areas

Bu çalışmada, Van Gölü ve Çevresi önemli patates ekiliş alanlarından Erciş ve Ahlat’ta topraktaki yabancı ot tohumlarının yoğunlukları, rastlanma sıklıkları ve bunların floraya yansıması araştırılmıştır. Erciş ve Ahlat patates ekiliş alanlarında 0-25 cm’lik toprak derinliğinde Amaranthus retroflexus L. ve Portulaca oleracea L. tohumlarının en yoğun türler olduğu saptanmıştır. Topraktaki tohum rezervinin floraya yansıma oranının Erciş’te sadece 2007 yılında %1.2; bunun dışında %1’den düşük olduğu belirlenmiştir.In this study it was investigated in order to determine density of weed seeds and reflection to flora at Ercis and Ahlat. The most common weed species were determined as to Amaranthus retroflexus L. and Portulaca oleracea L. in dept 0-25 cm of soil reservoir at Ercis and Ahlat fields. The ratio of reflection to flora of seed reservoirs in soil is determined lower than 1% as well. But this ratio in Ercis is found 1.2% in 2007

Synthesis of an injectable heparin conjugated poloxamer hydrogel with high elastic recoverability for temporomandibular joint disorders

The temporomandibular joint (TMJ) is commonly affected during fundamental oral activities, reducing the quality of life. Herein, we synthesized a heparin-conjugated poloxamer hydrogel (HEP) as a thermo-responsive injectable hydrogel for the treatment of TMJ disorders. While the gelation temperature of synthesized HEP (25% [w/v]) was 29.8-30.0 degrees C, there was a slight difference between loss and storage modulus. HEP decreased the friction of the TMJ, thus requires less energy during load-bearing jaw movement in comparison to POL. Moreover, the oscillation test dependent on strain ranges from 0.01% to 1000% validated that POL and HEP3 hydrogels showed a similar critical strain of about 5.6%. The total elastic recovery percentage of HEP3 (53.50%) was higher than POL (45.55%), indicating a better recovery of the deformed hydrogel structure. Along with the suitable viscoelastic properties for temporomandibular cavity, both hydrogels increased the proliferation of fibroblasts (L929) and chondrocytes (ATDC5) (cell viabilities were above 100%). However, newly synthesized HEP induced differentiated cell proliferation of chondrogenic cells at increasing concentrations up to 0.0156 mg/mL (p < 0.0001) compared to POL and the control group. The promising rheological properties and effects on chondrogenic cell proliferation of injectable heparin-conjugated hydrogel make them candidates for intra-articular injections used for the treatment of TMJ

Genetic diversity and relationship analysis among accessions of Aegilops ssp in Turkey using amplified fragment length polymorphism (AFLP) markers

Amplified fragment length polymorphism (AFLP) DNA markers were used to assess the genetic diversity and relationships between 55 accessions of genus Aegilops, including the species Aegilops triuncialis L. (UUCC), Aegilops geniculata Roth (MMUU), Aegilops cylindrica Host (CCDD) and Aegilops umbellulata Zhuk (UU). The samples were collected from Aegean region and East Anatolia, Turkey. 16 AFLP selective primer combinations generated a total of 3200 polymorphic amplification products. 50 Aegilops accessions were analyzed using the data analysis software, unweighted pair-group method arithmetic average (UPGMA) method and numerical taxonomy and multivariate analysis system (NTSYSpc-2.02k). The similarity index coefficients were calculated according to simple matching coefficient. Using 16 AFLP primer combinations, species from Aegean region and east Anatolia were clustered as four major groups. Aegilops species having U genome clustered together and A. cylindrica host was out grouped