Silicon Drift Detector Readout Electronics for a Compton Camera

A prototype detector for Compton camera imaging is under development. A monolithic array of 19 channel Silicon drift detector with on-chip electronics is going to be used as a scatter detector for the prototype system. Custom designed analog and digital readout electronics for this detector was first tested by using a single cell Silicon drift detector. This paper describes the readout architecture and presents the results of the measurement.Comment: 10 pages, 9 figures, submitted to Nucl. Instr. Meth.

Data acquisition, event building and signal reconstruction for Compton camera imaging

Nurdan, K&#305;vanç <br /> <br /> Die Compton-Camera ist ein neues Detektorsystem zur bildlichen Darstellung von radioaktiven Markierungssubstanzen im Bereich der Gammastrahlung, das prinzipiell eine besonders gute Ortsauflösung und hohe Empfindlichkeit liefern kann. Die ist von grosser Bedeutung für die moderne bio-medizinische Forschung oder für darauf basierende diagnostische Verfahren. Dafür ist ein neues Konzept einer software-basierten Koinzidenzmessung entwickelt worden, das auf den bereits vorhandenen Datenaufnahmesystemen der Hochenergiephysik aufbaut, bei denen die Information von mehreren Tausend Kanälen von verschiedenen Detektortypen zusammengefügt werden. Auf der Basis der Digitalisierung analoger Signale durch FADCs (flash analog to digital converters), einer modernen Struktur einer ersten Stufe von Prozessoreinheiten, realisiert durch FPGAs (field programmable gate arrays) und einer erweiterbaren schnellen Busstruktur, wurde ein System aufgebaut, bei dem die Signale von einem 19-kanaligen Streudetektor und einem Absorptionsdetektor (Anger-Camera) eindeutig zusammengefügt werden konnten. Die Verwendung von Zeitmarkierungen spielte dabei eine zentrale Rolle, um die Zuordnung der Signale der Detektorkomponenten von der asynchronen Erzeugung in den synchronen Teil der weiteren Verarbeitung zu erhalten. Mit diesem Datenaufnahmesystem ist es erstmals gelungen, Signale von Silizium-Drift Detektoren, die durch Compton-Elektronen erzeugt wurden, und Signale des gestreuten Gamma-Quanten, die in dem zweiten Absorptionsdetektor erzeugt werden, zu Paaren zusammenzusetzen und damit die Streuereignisse zu rekonstruieren, wobei eine Winkelgenauigkeit von etwa 1° erreicht wurde. Diese Genauigkeit liegt nahe an dem theoretisch erwarteten Wert. Bisher gab es keine Anhaltspunkte über den Einfluss eines Prozessors auf die erzielte Qualität bei einer Bildaufnahme. Der übliche Weg über die Beschreibung einer "Detective Quantum Efficiency" (DQE) wurde daher auf diesen Prozess erweitert. Dazu wurden mit Hilfe des Monte-Carlo-Verfahrens Simulationen mit Zeitmarken über das Totzeitverhalten dieses "software"-basierten Koinzidenzsystems durchgeführt. Es konnte gezeigt werden, dass das neue System sich im Wesentlichen so verhält, als würde es durch eine "paralysierende" Totzeit bei höheren Raten limitiert. Genauere Untersuchungen zeigen, dass dafür die Zeitdauer zur Verarbeitung eines Ereignisses in dem Prozessor und die Tiefe des Puffers massgebend sindwas für spätere Echtzeitanwendungen und Weiterentwicklungen von Bedeutung ist. Die zur Zeit verfügbare neuester Generation von Prozessoren sind aber durchaus in der Lage ohne allzu grosse Verluste den Anforderungen eines komplexen Detektors zu genügen.Nurdan, K&#305;vanç <br> <br> The Compton camera is a new detector system for imaging radioactively labeled nuclides in the range of &#947;-rays that can in principle provide extremely good resolution and high sensitivity. This is invaluable for the modern bio-medicine research or diagnostic studies based on it. For this system a new concept of software based coincidence measurements has been developed; inspired by the data acquisition systems built for high energy physics, where the information from thousands of channels of various detectors has to be merged. A data acquisition system based on digitizing analog signals with FADCs (flash analog to digital converters) has been built consisting of a modern structure of first level processor unit realized with FPGAs (Field Programmable Gate Arrays) and an extendable fast data bus. The developed data acquisition system is capable of collecting the signals from a 19-channel scatter detector and an absorption detector (Anger camera) unambiguously. Here the usage of time stamping plays a central role in order to attribute the asynchronous signals of detector components to synchronous event fragments for further processing. With this data acquisition system it is shown for the first time that the signals from the silicon drift detector that are generated through Compton electrons and signals of scattered gamma quants produced in the second absorption detector can be put in pairs to reconstruct scattering events where an angular resolution of approximately 1° is achieved. This precision is close to the theoretically expected value. There has been no clue on the influence of a processor on the quality of the image acquisition till now. The usual way of defining "Detective Quantum Efficiency" (DQE) has been enhanced to this process. For this purpose, Monte Carlo simulations with time stamps over the deadtime relation of this software based coincidence system have been performed. It could be shown that this new system behaves as if it was limited with a paralyzable deadtime at high rates. More detailed analysis shows that the duration of processing an event in the processor and the depth of the buffers are decisive parameters that are for future real-time applications and further development essential. However, today\u27s available newest generation processors have the performance of fulfilling the requirements of complex detectors without considerable losses

THE ROLE OF BAITUL MAL IN EMPOWERMENT MUSTAHIQ ZAKAT WELFARE: THE STUDY OF BAITUL MAL KOTA LHOKSEUMAWE IN DISTRIBUTING ZAKAT PRODUKTIF

Zakat is a potential source of funds that can be used to build the independence and welfare of the poor. In practice, there are still many mustahiq who consider zakat as a free gift and are not responsible for its distribution. Based on the initial survey, it was known that the distribution of zakat in Baitul Mal was still not in proper use, and was still less productive, so it was assumed as an institution that was less active in empowerment the economy of the poor (mustahiq). Seeing these problems, the authors are interested in knowing the role of the ’amil zakat institution, especially Baitul Mal Lhokseumawe in an effort to empower the mustahiq zakat economy through a study of strategies for optimizing the distribution of productive zakat in Lhokseumawe City. This study aimed to determine the role of Baitul Mal Lhokseumawe in improving and empowering the economy of mustahiq through optimizing the distribution of productive zakat. While the target of this activity was to increase the independence and economic welfare of the poor, through a study on the optimization in distribution practices of zakat produktif at Baitul Mal Lhokseumawe. To achieve these objectives, a descriptive qualitative approach was used with observation, interviews and documentation techniques. Meanwhile, data analysis was carried out through the methods of collection, reduction, display, and conclusion. As an amil zakat institution, Baitul Mal actively empowered the economy of the poor in Lhokseumawe City by always coordinatingwithBMGandimplementingtransparent,professionalandaccountablezakat management. In an effort to optimize the distribution of productive zakat, in addition to providing business capital in cash to micro and medium entrepreneurs which amount to 1 million and 4 million per year, respectively, the Baitul Mal also oftened provides guidance in terms of the utilization of zakat funds for mustahiq. However, in the process of distributing zakat, BMG oftened faces complaints and criticism from the public, especially in terms of mustahiq zakat and an amount of zakat.Keywords:Role, Existence, Baitul Mal, Optimization, Distribution,andProductive Zaka

Yunanistan'da Osmanlı Mirası : 19. Yüzyılda Türk Emlaki Meselesi (1830-1850)

[No Abstract Available

Osmanlı Devleti'nden ABD'ye Ermeni Göçü (1860-1914) ve Ermeni Sorunu Üzerindeki Etkisi

[No Abstract Available

Toplumsal Cinsiyet Eşitliği Açısından Bir Çizgi Film Çözümlemesi: PEPEE

Mass media play an important role in the formation and continuation of the concept of gender equality within society. The purpose of this research is to analyze and evaluate the cartoon series called “Pepee” according to the concept of gender equality. Presentation of gender roles through various educational tools in society is important in terms of the construction and formation of children's perspective about gender.This is a descriptive study utilizing a qualitative research design. The study sample which was analyzed was composed of 45 episodes of the Pepee cartoon series. Research data were analyzed both using the methods of content analyses and semiotics. It was revealed that both the female and male characters of this cartoon limited by gender roles in terms of stereotypes which are related to gender equality, actions, colors and the types of clothing and also it was revealed that it includes messages which mat reproduce sexist viewpoints. Based on the analyses, considering the findings in a holistic sense, it was observed that, the Pepee cartoons did contain messages of gender inequality.Analyses showed that even though many of the activities illustrated in the cartoon can be performed by both males or females, there were many activities, such as watering flowers, setting the table, and taking care of the baby, which were solely attributed to the female characters, while activities such as, driving a car, and riding a bicycle or a balloon were attributed to the male characters. Messages of gender inequality were identified in all episodes regarding such aspects as clothing colors, clothing types, emotional situations and the games played by the characters.All cartoons designed for educational purposes should involve episodic content and program scenarios to be in line with the principals of human rights and equality. All parts of the components of the societal system such as these cartoons have the responsibility in the society to prevent gender discrimination, as well as to promote gender equality awareness.Kitle iletişim araçlarının, toplumsal cinsiyet eşitliği anlayışının, toplumda oluşmasında ve yerleşmesinde önemli rolleri bulunmaktadır. Bu araştırmanın amacı, Pepee adlı çizgi filmi toplumsal cinsiyet eşitliği açısından çözümlemek ve değerlendirmektir. Çünkü toplumsal cinsiyet rollerinin çeşitli araçlar yoluyla sunumu, çocukların toplumsal cinsiyet konusundaki düşüncelerinin oluşmasında ve şekillenmesinde önemlidir.Araştırmanın modeli betimseldir ve nitel araştırma özelliği taşımaktadır. Araştırmanın çalışma evreni, Pepee çizgi filminin 45 bölümüdür. Veriler, içerik analizi ve göstergebilim ile analiz edilmiştir.Çizgi filmin hem kadın hem erkek karekterleri, toplumsal cinsiyete ilişkin kalıp yargılara uygun rol, eylemler, giysi rengi ve giysi türü içinde sınırladığı ve cinsiyetçi bakış açısını yeniden üretebilecek mesajların olduğu belirlenmiştir. Elde edilen bulgular bütünsel anlamda değerlendirildiğinde çizgi filmin toplumsal cinsiyet eşitsizliği oluşturan mesajlar içerdiği saptanmıştır.Çizgi filmde gösterilen etkinliklerin tamamı hem kadınlar,hem erkekler tarafından yapılabilecek işler olmasına karşın, çiçek sulama, sofra hazırlama, bebekle ilgilenme gibi işler, kadın karakterlere; otomobil, bisiklet ve balon kullanma gibi beceriler ise erkek karakterlere atfedilmiştir. Çizgi filmin izlenen tüm bölümlerinde, giysi renklerinden, giysi türlerine, duygusal durumlardan, oynanan oyunlara kadar toplumsal cinsiyet eşitsizliği oluşturabilecek mesajlar saptanmıştır.Eğitici amaçlı tüm çizgi filmler, senaryolarını ve içeriğindeki mesajlarını, insan hakları ve eşitlik temelinde kurgulamak zorundadır. Çünkü toplumda da kadın-erkek ayrımcılığını engellemek ve cinsiyet eşitliğini sağlama ve duyarlı olma konusunda sistemin her bir parçasının sorumluluğu bulunmaktadır

Novel gradient-based methods for data distribution and privacy in data science

With an increase in the need of storing data at different locations, designing algorithms that can analyze distributed data is becoming more important. In this thesis, we present several gradient-based algorithms, which are customized for data distribution and privacy. First, we propose a provably convergent, second order incremental and inherently parallel algorithm. The proposed algorithm works with distributed data. By using a local quadratic approximation, we achieve to speed-up the convergence with the help of curvature information. We also illustrate that the parallel implementation of our algorithm performs better than a parallel stochastic gradient descent method to solve a large-scale data science problem. This first algorithm solves the problem of using data that resides at different locations. However, this setting is not necessarily enough for data privacy. To guarantee the privacy of the data, we propose differentially private optimization algorithms in the second part of the thesis. The first one among them employs a smoothing approach which is based on using the weighted averages of the history of gradients. This approach helps to decrease the variance of the noise. This reduction in the variance is important for iterative optimization algorithms, since increasing the amount of noise in the algorithm can harm the performance. We also present differentially private version of a recent multistage accelerated algorithm. These extensions use noise related parameter selection and the proposed stepsizes are proportional to the variance of the noisy gradient. The numerical experiments show that our algorithms show a better performance than some well-known differentially private algorithm

Şiirin hüznü kasetlerde

Taha Toros Arşivi, Dosya No: 24-Attila İlha