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Treatment of an N-silyl-B-chloro-aminoborane with substoichio-metric quantities of Me3SiOTf afforded B–N coupling, whereas activation with 5 mol% of Ag[Al{OC(CF3)3}4] led to Cl/Me exchange between the boron and the silicon center. Combined experimental and computational studies of the latter process support a chain reaction that is initiated by nucleation-limited chloride abstraction.

Dissertation, RWTH Aachen University, 2018; Aachen 1 Online-Ressource (233 Seiten) : Illustrationen (2018). = Dissertation, RWTH Aachen University, 2018, Inorganic polymers, i. e., polymers with a backbone of inorganic (main group) elements, form a versatile class of materials. Since the 1960s, different elements and approaches have been investigated to obtain a variety of materials in order to supplement or replace classical organic polymers. While the most widely explored and used inorganic polymers are polyphosphazenes, polysiloxanes and polysilanes, the field also encompasses several boron-comprising polymers. BN-containing polymers like poly(aminoborane)s and different polyborazines are mainly used as shapable precursors for boron nitride ceramics, similar to poly(phosphinoborane)s leading to boron phosphide.In this thesis, a new class of BN-containing inorganic polymers, poly(iminoborane)s, is presented. The main obstacle in the formation of well defined linear poly(iminoborane)s [BRNR’]n is the preferred formation of cyclic borazines (n = 3) from monomeric precursors. This obstacle is overcome by introducing an ethylene bridge between two adjacent nitrogen atoms, thus making the formation of small rings impossible. This is accomplished by synthesizing a difunctional five-membered ring with an NBN moiety, i. e., a 1,3-bis(trimethylsilyl)-1,3,2-diazaborolidine. The five-membered ring was reacted with a dihaloborane to polymerize in a condensation reaction with trimethylsilyl halide elimination. First, a B-n-octyl substituted derivative was synthesized which was characterized by multinuclear NMR spectroscopy, GPC, DLS, SAXS, DSC, TGA and UV/vis spectroscopy and consists of 12–14 catenated BN units on average. The TGA shows that the ethylene bridges effectively stabilize the backbone also during the pyrolysis which leads to a ceramic yield nearly equalling the theoretical BN content. In the follow-up research, an aminoborylated derivative of the diazaborolidine was synthesized as a dormant monomer with an NBNB unit. The polymerization is started by adding a Brønsted acid such as HCl, HOTf or HNTf2 stoichiometrically. To compare the reactivities of the leaving groups, a distannylated diazaborolidine was polymerized with a dibromoborane. Additionally, the influence of the B-substituents was evaluated by synthesizing oligomers with n-butyl, phenyl and 4-n-butylphenyl groups at boron as well as oligomers with mixtures of these substituents. The best result with 18 catenated BN units is shown by the derivative with alternating n-octyl and phenyl groups. The glass transition temperatures range from −71 °C to 16 °C and increase with shorter alkyl chains as side groups and, most significantly, with a higher aryl group content. B3LYP-D3(BJ)/def2-SV(P) calculations for systems with methyl and phenyl substituents, respectively, confirm a helical shape with a translation of 5 repeat units.Another part of this work is concerned with the synthesis and characterization of naphthalene bisborinic imides and an anhydride derived from rylene imides and anhydrides, respectively. The latter are dyes used as n-type semi-conducting materials. By introducing differently substituted boron atoms in BNB or BOB fragments, the properties of the resulting dyes can be tuned. The BNB compounds with Mes or Tip as B-substituents are air- and moisture-stable, show promising values for the fluorescence quantum yields and were tested for the use in OFET devices. A B-phenyl substituted bisborinic anhydride degrades in air over time to the corresponding boroxine. The results are promising but require further exploration., Published by Aachen

Bu çalışma, raporlama birimleri, radyologlar ve görüntüleme merkezlerini tek erişim arayüzü üzerinde bağlayan, medikal görüntülere erişim hızını arttırıp rapor dönüş zamanlarını düşürerek raporlama verimliliğini arttıran, tetkik ve radyologlar arasında tecrübe ve uzmanlık alanları açısından en uygun eşleşmeyi belirleyerek rapor kalitesini arttıran Raporlama İş Akış Optimizasyon Algoritması (RİAOA) içeren bir bütüncül mimari önermektedir. RİAOA uygulamasında tetkik ve radyolog nitelikleri, DICOM, DICOM İçerik Haritalama Kaynağı ve Dünya Sağlık Örgütü (DSÖ) tanımlarına uygun bir hiyerarşik ontoloji yapısı kullanılarak modellenmiştir. Bu yapıdaki özellikler ve bağlantılar için radyologlar ve teknik uzmanlar tarafından atanan önem dereceleri karşılıklı matrisler haline getirilmiş öğelere ait ağırlıklar AHP kullanılarak hesaplanmıştır. Atama seçenekleri İlişki-Temelli Anlamsal Eşleme (İTAE) ve Tamsayılı Doğrusal Programlama (TDP) kullanılarak işlenmiştir. Sonuçlar gerçek uygulama verileri ve simüle edilmiş veriler üzerinde uzmanlık, rapor dönüş, iş yükü başarı oranları bazında değerlendirilmiştir. Simüle edilmiş veriler kullanılarak elde edilen sonuçlar, Dönüşümlü, En Kısa Kuyruk ve Rastgele atama yöntemleri ile karşılaştırılmıştır. İTEA yöntemi ile en yüksek uzmanlık başarı oranı elde edilmiş, İTEA ile TDP birleştirildiğinde ise rapor dönüş ve iş yükü başarı oranınında daha da iyi sonuçlar elde edildiği görülmüştür. İTEA ve TDP bazlı görüntü dağıtımı bant genişliği, depolama alanı ve donanımsal tıkanma ve gecikmeleri de engellemiştir.Tetkik raporlamaları için atamaların elle yapıldığı teleradyoloji uygulaması ile karşılaştırıldığında, önerilen mimarinin uzmanlık başarı oranını % 13,25, iş yükü başarı oranını % 34,92 ve rapor dönüş başarı oranını % 120 arttırdığı görülmüştür. Uygulamadaki toplam dönüş süresinde ise % 22,39 iyileşme sağlanmıştır. Önerilen mimari uygulaması toplamda 35 hastane, 13 birinci basamak sağlık kurumu, 3 mobil klinik ve 1 raporlama biriminin entegrasyonu ile test edilmiştir. 3.35 milyon tetkik arşivlenmiş, 14216 tetkik raporlama birimi tarafından raporlanmıştır. Organize bir raporlama sürecine dahil olan 6202 adet rapor RİAOA değerlendirmesinde kullanılmıştır. RİAOA entegre edilmiş olan mimari, 8 birinci basamak sağlık kurumu ve 3 kanser tarama birimi entegre edilerek pilotlanmıştır. Pilotlanan uygulama http://eradyoloji.saglik.gov.tr adresinde çalışır durumda olup Ankara Halk Sağlığı Müdürlüğü tarafından desteklenmektedir.Bu çalışmada önerilen mimari ve teknikler radyoloji raporlama hizmetinin, birden fazla görüntüleme merkezi tarafından, birden fazla radyoloji grubu ya da bireysel radyolog tarafından alındığı teleradyoloji uygulamalarında kullanılabilir ya da uygulanabilir. Bu mimarinin sunduğu avantajların büyük ölçekte en üst düzeye ulaşacağı değerlendirilmektedir. Finansal modeller bu mimari ile entegre edilip kısa rapor dönüş süreleri ve yüksek rapor kaliteleri ödüllendirilebilir. Tetkik başına raporlama hizmeti düşürülürken hizmet kalitesi arttırılabilmektedir. Performans değerlendirme, kalite kontrol ve iş yükü dağılım istatistik modülleri yönetimsel amaçlar ile bu mimariye entegre edilebilir. This study proposes an infrastructure with a global workflow management algorithm in order to interconnect facilities, reporting units and radiologists on a single access interface. This infrastructure is enhanced by a reporting workflow optimization algorithm (RWOA) to determine the optimum match between the inspection and radiologist in terms of experience, subspeciality, response time and workload parameters. RWOA increases the efficiency of the reporting process by decreasing access time to medical images and turnaround time of medical reports and increases the quality of medical reports.In RWOA implementation, inspection and radiologist attributes are modelled using a hierarchical ontology structure based on Digital Imaging and Communications in Medicine (DICOM) Conformance, DICOM Content Mapping Resource and World Health Organization (WHO) definitions. Attribute preferences rated by radiologists and technical experts are formed into reciprocal matrixes and weights for entities are calculated utilizing Analytic Hierarchy Process (AHP). The assignment alternatives are processed by relation-based semantic matching (RBSM) and Integer Linear Programming (ILP).The results are evaluated based on both real case applications and simulated process data in terms of subspecialty, response time and workload success rates. Results obtained using simulated data are compared with the outcomes obtained by applying Round Robin, Shortest Queue and Random distribution policies. It was concluded that RBSM gives the highest subspecialty ratings, but integrating ILP with RBSM ratings provides a better response time and workload success rate. RBSM and ILP based image delivery also prevents bandwidth, storage or hardware related stuck and latencies.When compared with a real case teleradiology application where inspection assignments were performed manually, the proposed solution was found to increase the subspecialty success rate by 13.25 %, increase the workload success rate by 34.92% and increase the response time success rate by 120%. The total response time in the real case application data was improved by 22.39%.The proposed architecture has been tested in a total of 35 hospitals, 13 primary care clinics, 3 mobile clinics, 1 reporting unit. 3.35 million inspections were archived and 14216 inspections were reported by the reporting unit. However, an organized reporting process was executed only for 6202 reports which were utilized for RWOA evaluation. The proposed architecture with RWOA is piloted to provide reporting service for 8 primary care and 3 cancer screening medical imaging centers. The piloted application is currently available at http://eradyoloji.saglik.gov.tr supported by the Governship of Public Health, Ankara, Turkey.The insfrastructure and techiniques suggested in this study can be used for or applied to teleradiology applications where the reporting service is outsourced by multiple medical centers to multiple radiology groups or individual radiologists. It is considered that the advantage of the infrastructure will be maximized in large scale applications. Financial models can also be integrated with this architecture where shorter turnaround time and high quality reports can be promoted. The cost of the reporting service per inspection is decreased while the quality of service is increased. Performance assessment, quality control and workload distribution statistics modules can be integrated on this architecture for administrative purposes. 133

This paper proposes a framework designed to interconnect medical imaging facilities and teleradiology service providers on a single access interface. This framework aims to solve the interoperability issues of Picture Archiving and Communication System (PACS), Radiology Information System (RIS) and Hospital Information System (HIS) developed by different vendors and enrich the digital health record delivered to non-local radiologists or physicians with the integrated information from several systems. This is achieved by introducing a "Grid Agent" into the domain of medical software systems, which seamlessly integrates with present systems and forms a network to deliver data between other Grid Agents and the "Grid Manager". Resultant solution decreases the access time of medical images by non-local medical staff and increases the efficiency and durability of the teleradiology service architecture.

In this study, RF coil geometries are designed for MRI applications using in-homogeneous main magnetic fields. The current density distributions that can produce the desired RF magnetic field characteristics are obtained on prede-fined cubic, cylindrical and planar surfaces and Tikhonov, CGLS, TSVD and Rutisbauer regularization methods are applied to match the desired and gen-erated magnetic fields. The conductor paths, which can produce the current density distribution calculated for each surface selection and regularization technique, are determined using stream functions. The magnetic fields gen-erated by the current distributions are calculated and the error percentages between the desired and generated magnetic fields are found. Optimum con-ductor paths that are going to be produced on cubic, cylindrical and planar surfaces and the required regularization method are determined on the basis of error percentages and realizability of the conductor paths.The optimum conductor path calculated for the planar coil is realized andin the measurement done by LakeShore 3-Channel Gaussmeter, an average error percentage of 11 is obtained between the theoretical and measured mag-netic field. The inductance values of the realized RF coil are measured; the tuning and matching capacitance values are calculated and the frequency char-acteristics of the system is tested using Electronic Workbench 5.1. The quality factor value of the tested system is found to be 162.5, which corresponds to a bandwidth of 39.2 KHz at 6.387 MHz (operating frequency of METU MRI system).The techniques suggested in this study can be used in order to design and realize RF coils on predefined arbitrary surfaces for inhomogeneous main mag-netic fields. In addition, a hand held MRI device can be manufactured which uses a low cost permanent magnet to provide a magnetic field and generates the required RF field with the designed RF coil using the techniques suggested in this study.Keywords: Magnetic Resonance Imaging, Rf Coil Design, Inhomogeneous Main Magnetic Field, Rf Field, Stream Functions, Basis Functions, Method of Moments, Surface Current Density 146

ÖZET İnsanların bulunduğu ortamlardaki olası faydalan dolayısıyla geçtiğimiz otuz yıl, insansı robotlara karşı giderek artan bir ilgi ve meraka şahitlik etti. Ne var ki, insansı robotların dinamiklerinin doğrusal olmaması ve birçok serbestlik derecesine sahip olmaları denetimlerini güçleştirmektedir. Açık devre yürüyüşten birçok algılayıcı ve geri besleme çemberine sahip sistemlere kadar sayısız güzergah belirleme ve yürüyüş denetim yaklaşımı önerilmiştir. Yürüyüş referansının parametrelerinin ayarlanması karşılaşılan genel bir problemdir. Bir diğer problem de ayağın yere konma anında yaşanan geçici durum davranışlarıdır. Bu tezde önerilen metot üst vücut için çevrim-dışı güzergah referansları vermektedir. Bu referanslara karşı gelen destek ayağında oluşması gereken eklem momentlerinin elde edilmesi amacıyla eniyileme teknikleri kullanılmıştır. Hareket, belli yönlerde pozisyon denetimine, belli yönlerde ise sanal ağırlık beslemesine dayanan salınım ayağı denetim stratejisiyle sağlanır. Bu metotla ayağın yere yumuşak konması sağlanabilir ve düşük empedans probleminin kolaylıkla üstesinden gelinebilir. Bu metodun bir diğer avantajı da yürüyüşün sağlanması için sınırlı sayıda parametrenin gerekmesidir. Önerilen metodun test edilmesi için 12 serbestlik derecesine sahip bir insansı robotun üç boyutlu dinamik ve yerle etkileşim benzeşim teknikleri kullanılmıştır. Benzeşimler, bu metodun gerçek uygulamalarda kullanılabilirliğini ortaya koymaktadır. ABSTRACT Past three decades witnessed a growing interest in biped walking robots because of then- advantageous use in the human environment. However, their control is challenging because of their many degrees of freedom and non-linearities in their dynamics. Various trajectory generation and walking control approaches ranging from open loop walking to systems with many sensors and feedback loops have been reported in the literature. The tuning of the parameters of reference gait is a common complication encountered. Another important problem of the walking control is the contact transients at the instant of landing. The method presented in this thesis generated position references for the upper body. Optimization techniques are employed to obtain suitable leg joint torques for the supporting leg to track body reference trajectories. Locomotion is achieved by a swinging leg control scheme, which is based on position control on certain directions, and artificial gravity compensation on certain directions. Soft landing and low impedance problem of the legs can easily be handled with this scheme. Another advantage is that limited number of parameters is required for gait generation. 3D dynamics and ground interaction simulation techniques are employed for a 12-DOF biped robot to test the proposed method. The simulations indicate the applicability of the method in real implementations. IV 77