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Monitoring of Intracerebral Hemorrhage With a Linear Microwave Imaging Algorithm
No full textIntracerebral hemorrhage is a life-threatening condition where conventional imaging modalities such as CT and MRI are indispensable in diagnosing. Nevertheless, monitoring the evolution of intracerebral hemorrhage still poses a technological challenge. We consider continuous monitoring of intracerebral hemorrhage in this context and present a differential microwave imaging scheme based on a linearized inverse scattering. Our aim is to reconstruct non-anatomical maps that reveal the volumetric evolution of hemorrhage by using the differences between consecutive electric field measurements. This approach can potentially allow the monitoring of intracerebral hemorrhage in a real-time and cost-effective manner. Here, we devise an indicator function, which reveals the position, volumetric growth, and shrinkage of hemorrhage. Later, the method is numerically tested via a 3D anthropomorphic dielectric head model. Through several simulations performed for different locations of intracerebral hemorrhage, the indicator function-based technique is demonstrated to be capable of detecting the changes accurately. Finally, the robustness under noisy conditions is analyzed to assess the feasibility of the method. This analysis suggests that the method can be used to monitor the evolution of intracerebral hemorrhage in real-world scenarios. Graphical abstract: [Figure not available: see fulltext.]. © 2022, International Federation for Medical and Biological Engineering
Affection for Nouvel Architecture: on Contemporary (islamic) Architecture and Affect
No full text[No abstract available
Factors Affecting Site-Specific Response Analysis
No full textThe engineering purpose of a site-specific response analysis is to estimate the uniform hazard acceleration spectrum on the ground surface for a selected hazard level. One of the mandatory components for site response analyses is one or more representative acceleration time histories that need to be scaled with respect to the calculated seismic hazard level for the selected site. The selection and scaling procedures of earthquake acceleration records play an important role in this approach. The effects and differences in using two different scaling approaches are studied: scaling with respect to ground motion parameters and response spectrum scaling. A set of homogeneous ground motion prediction relationships are developed for peak ground acceleration, peak ground velocity, root-mean-square acceleration, Arias intensity, cumulative absolute velocity, maximum spectral acceleration, response spectrum intensity, and acceleration spectrum intensity based on a uniform set of acceleration records for ground motion parameter scaling.The uncertainties associated with site response analysis are considered as epistemic and aleatory uncertainties in source characteristics, soil profile, and soil properties. Aleatory variability is due to the intrinsic randomness of natural systems; it cannot be reduced with additional data (Passeri et al. 2020), however; its variability may be modeled by probability distribution functions. Thus, one possibility is to determine the probability distribution of the acceleration spectrum calculated on the ground surface for all possible input acceleration records, site profiles, and dynamic soil properties. The variability in the earthquake source and path effects are considered using a large number of acceleration records compatible with the site-dependent earthquake hazard in terms of fault mechanism, magnitude, and distance range recorded on stiff site conditions. Likewise, a large number of soil profiles may be considered to account for the site condition variability. The uncertainties related to dynamic soil properties may be considered as possible variability of maximum dynamic shear modulus in site response analyses. A methodology is proposed to estimate a uniform hazard acceleration spectrum on the ground surface based on the probabilistic assessment of the factors involved in site response analysis. The uniform hazard acceleration spectra obtained from a case study are compared with the spectra calculated by probabilistic models proposed in the literature
Perceiving Societal Pressure To Be Happy Is Linked To Poor Well-Being, Especially in Happy Nations
No full textHappiness is a valuable experience, and societies want their citizens to be happy. Although this societal commitment seems laudable, overly emphasizing positivity (versus negativity) may create an unattainable emotion norm that ironically compromises individual well-being. In this multi-national study (40 countries; 7443 participants), we investigate how societal pressure to be happy and not sad predicts emotional, cognitive and clinical indicators of well-being around the world, and examine how these relations differ as a function of countries' national happiness levels (collected from the World Happiness Report). Although detrimental well-being associations manifest for an average country, the strength of these relations varies across countries. People's felt societal pressure to be happy and not sad is particularly linked to poor well-being in countries with a higher World Happiness Index. Although the cross-sectional nature of our work prohibits causal conclusions, our findings highlight the correlational link between social emotion valuation and individual well-being, and suggest that high national happiness levels may have downsides for some
Türkiye-ermenistan İlişkilerinin Futbol Diplomasisi Bağlamında Değerlendirilmesi
No full textUluslararası ilişkilerde; siyaset ve sporun bir arada bulunması ve bir-birini etkilemesi hususunda pek çok örnek mevcuttur. 1971 yılında, Pekin hükûmetinin Amerikan masa tenisi takımını Çin’e davet etmesiyle başlayan ve tarihe “masa tenisi diplomasisi” olarak geçen süreç, Amerika Birleşik Devletleri Başkanı Richard Nixon’ın Çin’e karşı uygulanan ticari ambargoları kaldırması ve Amerika’ya gelmek isteyen Çin vatandaşlarına vize verilebileceğini bildirmesiyle sonuçlanmıştır. 2004 senesinde Hindistan ve Pakistan arasında yıllardır süregelen siyasi gerginliğin, “kriket diplomasisi” olarak adlandırılan süreçle aralarındaki düşmanlığı sona erdirmek için karşılıklı olarak, güven artırıcı önlemleri güçlendirme kararı almaları da sporun bir yumuşak güç unsuru olarak kullanılmasına başka bir örnek teşkil etmiştir. Diğer yandan spor ve siyasetin birbirlerini etkiledikleri süreçlerin olumlu oldukları kadar başarısızlıkla sonuçlanan durumları da bulunmaktadır. Bu çalışma, genel anlamda kamu diplomasisi bakışından “spor diplomasisinin”, daha spesifik olarak “futbol diplomasisinin” Türkiye-Ermenistan ilişkileri çerçevesinde analizine odaklanmaktadır. Bu bağlamda, iki ülke arasındaki ilişkilerin geliştirilmesi için futbolun bir araç olarak kullanılmasında hangi koşulların belirleyici olduğu ve futbol diplomasisinin iki ülke arasındaki iliş-kilere olumlu etki yapması için hangi koşulların mevcut olması gerektiği soruları ön plana çıkmaktadır. Çalışmada; ilk olarak, sporun diplomasi için el-verişli bir araç olarak kullanılmasının önemini analiz eden kavramsal çerçeve ortaya konulduktan sonra, Türkiye-Ermenistan ikili ilişkilerine etki eden dönemin siyasi ve sosyal ortamı analiz edilecektir. Sonuç olarak, bu çalışma, uluslararası ilişkilerde iki devlet arasındaki ilişkilerin normalleştirilmesinde bir araç olarak futbol diplomasisinin ortaya koymuş olduğu fırsatlar ve uygulamadaki sınırlar bağlamındaki potansiyelinin bir analizi olacaktır
An Fpga Implementation of Givens Rotation Based Digital Architecture for Computing Eigenvalues of Asymmetric Matrix
No full textThis paper proposes the digital circuit design that performs the eigenvalue calculation of asymmetric matrices with realvalued elements. Eigenvalues are computed iteratively through the QR algorithm. In the QR algorithm, the input matrix is factorized into orthogonal Q and upper triangular R matrix, then the RQ product is calculated to obtain an iterated matrix. For a time-efficient QR decomposition process, the Givens Rotation (GR) Principle is utilized to benefit from the parallelization feature. Parallelization is managed by the Systolic Array (SA) architecture that is created by placing Givens Generation (GG) and Row Updates (RU) blocks in a triangle array. In this paper, 4×4 input matrix is used to create a TSA architecture including n-1 diagonal (GG), and (n ∗ (n−1))/2 off-diagonal (RU) modules. In the results section, Givens Rotation is compared with the Gram Schmidt algorithm used in our previous study [1] in terms of error, and area usage
Single-Slice Microwave Imaging of Breast Cancer by Reverse Time Migration
No full textPurpose Microwave imaging of breast cancer is considered and a new microwave imaging prototype including the imaging algorithm, the antenna array, and the measurement configuration is presented. The prototype aims to project the geometrical features of the anomalies inside the breast to a single-slice image at the coronal plane depending on the complex dielectric permittivity variation among the tissues to aid the diagnosis . Methods The imaging prototype uses a solid cylindrical dielectric platform, where a total of 24 optimized Vivaldi antennas are embedded inside to form a uniform circular antenna array. The center of the platform is carved to create a hollow part for placement of the breast and the multistatic, microwave scattering parameters are collected with the antenna array around the hollow center. The dielectric platform further enhances the microwave impedance matching against the breast fat tissue and preserves the vertical polarization during the measurements. In the imaging phase, a computationally efficient inverse electromagnetic scattering method-reverse time migration (RTM)-is considered and adapted in terms of scattering parameters to comply with the actual measurements. Results The prototype system is experimentally tested against tissue-mimicking breast phantoms with realistic dielectric permittivity profiles. The reconstructed single-slice images accurately determined the locations and the geometrical extents of the tumor phantoms. These experiments not only verified the microwave imaging prototype but also provided the first experimental results of the imaging algorithm. Conclusions The presented prototype system implementing the RTM method is capable of reconstructing single-slice, nonanatomical images, where the hotspots correspond to the geometrical projections of the anomalies inside the breast
A New Learning Community for Educating Future Teachers: Online Baboratory School
No full textTo provide quality mathematics education for disadvantaged groups of middle school students and continue to offer quality practicum experience to future teachers during the Covid 19 outbreak, we founded the Online Laboratory School. This school was free and open to public school students: 130 middle school students throughout Turkey attended for a 5-week period. There were 25 pre-service teachers actively involved in teaching, under the close supervision of 7 university supervisors. The entire gamut of planning, teaching and reflection sessions for each virtual class were recorded via an e-learning platform. Additionally, survey data was collected from the participating students, parents, pre-service teachers and supervisors. Our findings indicate that we were able to build a unique and virtual learning community. While pre-service teachers and middle school students benefited the most, university supervisors also reported improving their skills on when and how to give feedback. We describe how the school functioned and the range of opportunities it provided to all participants considering situated-learning perspectives and building online-learning communities. We also discuss how this model can be used in the future as a strong asset for teacher education programs and adaptation of fieldwork practices
Modern Kıyının İnşası: 19. Yüzyıldan 21. Yüzyıla İstanbul’da Dört Kıyı Dolgu Projesi Üzerinden Toprağın ve Kentsel Dönüşüm Atığının Metabolik Akışı
No full textMetabolize olmuş sosyo-doğalar olarak kentlerin ve ekonomilerin inşasının önemli bir unsuru olarak kıyı şehirleri, kapitalizmin tarihi boyunca kırılgan ekolojik nişler olarak işlev gördüler. Su ile karanın buluştuğu bu şehirlerden biri olan İstanbul, günümüzün kapitalist koşullarında sosyo-ekolojik açıdan baskı altında. Bu baskının kentteki mekânsal karşılıklarından biri olan kıyı dolgu alanlarının İstanbul’daki yüzey toplamı, 2000’li yıllarda yeni bir ilçe oluşturabilecek boyuta ulaştı. Dünyanın pek çok yerinde mülk sahipliğine konu olan ve yeryüzündeki dramatik coğrafi müdahalelere yol açan kıyı dolgu projeleri; toprak erozyonu, sediment oluşumu, bozulan hidroloji ve arazi çökmesi gibi tehlikeli sonuçlara yol açmaya devam ediyor. Bu çalışma, dört kıyı dolgu projesi aracılığıyla İstanbul'un modern kıyılarını anlamak için kentsel toprağın ve kentsel dönüşüm atığının metabolik yolculuğunun tarihsel olarak bir süreliğine kıyı dolgu alanları formunda nasıl mekânsallaştığını araştırıyor. İncelenen kentsel kıyı dolgu projelerinin ilk ikisi 19. yüzyılda karşımıza çıkan Yenikapı dolgu alanı ve bağlantılı liman alanı önerisi ile İstanbul Limanı projesi iken; diğer ikisi de 21. yüzyılda Maltepe ve Yenikapı’da gerçekleştirilen kıyı dolgu projeleridir. Makalede; doğanın çeşitli dolaşımlarla nasıl mekânsallaştığının öyküsü araştırılıyor. Kentsel projelerin, İstanbul’un derinleşen eşitsiz coğrafyasında sosyoekolojik ilişkileri kırılganlaştırarak dönüştüren kapitalizmin enstrümanlarına bağlı olduğu kadar, mimarlığı ve hepimizi son derece yakından ilgilendiren kentsel gündemlere ve tahayyüllere de bağlı olduğu iddia ediliyor. Bunu yaparken, kentsel metabolizma perspektifinden kentsel toprağın ve kentsel dönüşüm atığının metabolik yolculuğunu inceleyerek kıyının üretiminde etkili olan mevcut çevresel ve yönetsel müdahaleler kadar olası gelecek tahayyüllerinin ve projeksiyonlarının da yeniden gözden geçirilmesine katkıda bulunmayı umut ediyor