Constrained Min-Cut replication for K-Way hypergraph partitioning

Cataloged from PDF version of article.Replication is a widely-used technique in information retrieval and database systems for providing fault tolerance and reducing parallelization and processing costs. Combinatorial models based on hypergraph partitioning are proposed for various problems arising in information retrieval and database systems. We consider the possibility of using vertex replication to improve the quality of hypergraph partitioning. In this study, we focus on the constrained min-cut replication (CMCR) problem, where we are initially given a maximum replication capacity and a K-way hypergraph partition with an initial imbalance ratio. The objective in the CMCR problem is finding the optimal vertex replication sets for each part of the given partition such that the initial cut size of the partition is minimized, where the initial imbalance is either preserved or reduced under the given replication capacity constraint. In this study, we present a complexity analysis of the CMCR problem and propose a model based on a unique blend of coarsening and integer linear programming (ILP) schemes. This coarsening algorithm is derived from a novel utilization of the Dulmage-Mendelsohn decomposition. Experiments show that the ILP formulation coupled with the Dulmage-Mendelsohn decomposition-based coarsening provides high quality results in practical execution times for reducing the cut size of a given K-way hypergraph partition. © 2014 INFORMS

AN EVALUATION ON TS-10465 AND TS EN 12504/1 FOR THE DETERMINATION OF COMPRESSIVE STRENGTH OF HARDENED CONCRETE

İmalatı tamamlanmış betonarme yapılara ait yapı elemanlarının basınç dayanımlarının tayin edilmesi için, tahribatlı bir deney yöntemi olan karot numunesi alınması ve tahribatsız bir deney yöntemi olan yüzey sertliği metodu, yaygın olarak ayrı ayrı veya birlikte kullanılmaktadır. Ülkemizde, sertleşmiş betondan karot alınması ve test edilmesi ile ilgili temel hususlar, TS 10465 ve TS EN 12504/1 standartları ile belirlenmiştir. Halen yürürlükte olan bu standartlarda belirtilen numune alma yöntemi ve hesap esasları ile ilgili önemli tereddütler mevcuttur. Bu çalışmada, ilgili standartlar irdelenerek, bu standardın eksiklikleri ve çelişkileri ortaya konulmuş ve çözüm önerileri sunulmaya çalışılmıştır. Yapı stoğunun çoğunu betonarme yapıların oluşturduğu ve mevcut yapıların yapısal dayanımları ile ilgili ciddi şüphelerin var olduğu ülkemizde, bu standartça önerilen yöntemler ile yapılan analizler çok büyük önem taşımaktadır. Dolayısıyla bu standart ile ilgili oluşan tereddütlerin ortadan kaldırılması, bu konu ile ilgili çalışan mühendislerimizin daha doğru değerlendirme yapabilmesini sağlayacaktır. In order to determine the compressive strength in structures components of finished reinforced concrete systems, the destructive method of obtaining core samples and the non-destructive method of surface hardness method are widely used separately or together. In Turkey, basic principles about obtaining samples in hardened concrete in structures and the tests applied are based on TS 10465 and TS EN 12504-1 standards. However, there seems to be serious conflicts in these standards about the method for obtaining samples and their calculation principles. In this study, considering these standards, existing drawbacks and uncertainties were emphasized and related solution proposals were presented. Accounting the percentage of reinforced concrete structures in our country, these standards become more crucial; thus, it is essential to remove these serious doubts about considered strength analyzing methods for helping our engineers to evaluate in a better way

The Relationship Between Motor Performance And Activities Of Daily Living In Children With Neurodevelopmental Disorders

Bu çalışmada, Nörogelişimsel Bozukluğu olan çocukların motor performans açısından değerlendirilmesi ve yetersizlik görülen alanların tespit edilerek belirlenen bu problemlerin önleminin alınmasıyla uygun eğitsel ve fizyoterapi rehabilitasyon programlarının planlanmasına yön verilmesi amaçlanmaktadır. Çalışmaya 4,5 14,5 yaş arasında Nörogelişimsel Bozukluk tanısı alan 6 Down sendromlu, 20 Otistik, 22 Özgül Öğrenme Güçlüğü, 59 Mental Retarde ve 36 sağlıklı olmak üzere toplam 143 çocuk dahil edilmiştir. Çalışmaya katılmayı kabul eden bütün olguların genel bilgileri kayıt edildikten sonra değerlendirmeleri Bruininks-Oseretsky Motor Performans Testi ve Wee-FIM yaşam kalite indeksi ile yapıldı. Araştırmaya 60 kız, 83 erkek çocuk katıldı. Hasta çocukların yaş ortalamaları 9,96±2,27 idi. Sağlıklı çocukların yaş ortalamaları 8,72±1,98 idi. Hasta çocuklarda motor performansı ölçen 12 alt testten 10 tanesinde motor performans ile günlük yaşam aktivitelerinden kendine bakım ve sfinkter kontrolü arasında yüksek düzeyde korelasyon bulunurken, diğer günlük yaşam aktiviteleriyle herhangi bir ilişki saptanamadı (p<0.05). Çalışmamızın sonuçlarında da görüldüğü gibi motor performansı iyi Nörogelişimsel Bozukluğu olan çocuklarda günlük yaşam aktivitelerinde yaşanan problemlerin az olabileceği görülmektedir. Rehabilitasyon programları düzenlenirken geniş yelpazede fiziksel değerlendirme ve fiziksel eğitim parametreleri göz ardı edilmemelidir.The purpose of this study was to evaluate the motor performance of children with Neurodevelopmental Disorders, identify the areas with deficiencies and by taking the necessary precautions and thus providing direction for planning appropriate educational and physiotherapy rehabilitation program. 6 children with Down Syndrome, 22 children with Learning difficulties, 59 children with Mental Retardation, 20 children with Autism; a total of 107 children with Neurodevelopmental disorders and 36 healthy subjects were included in the study. The subjects who agreed to participate were assessed first with a demographic assessment then with the Bruininks-Oseretsky Test of Motor Performance and WeeFIM functional independence measure index. 60 female and 83 male patients were included in the study. The mean age of the patients was 9,96±2,27. The mean age of the healthy subjects was 8,72±1,98. A high correlation was found between 10 sub-tests out of 12 measuring motor performance, and the Self-care and Sphincter Control parameters of the WeeFIM functional independence measure in children with Neurodevelopmental Disorders and no other relationship was found between the other parameters of WeeFIM (p <0.05). As seen in the results of our study, children with Neurodevelopmental Disorders who have good motor performance are seen to have fewer problems in daily living activities. When the rehabilitation program is constructed, physical assessment parameters and a wide range of physical education should also be added

Design and Development of a Multi Degree of Freedom Surgical Robot Manipulator that will be Utilized in Single Incision Laparoscopic Surgery

This thesis focuses on design and development of a robot manipulator with dexterous forceps for single-incision laparoscopic surgery. Integrating the robotic capabilities into laparoscopy instruments, the study aims to increase precision and reduce limitations such as mobility constraints. Main objective of the thesis is to develop a robotic articulating laparoscopy instrument. In light of the first trials, it is seen that the dexterity and robotic control advantages are promising while the trocar&apos;s mobility constraint limits the workspace of the robotic laparoscopy forceps. An alternative surgical robot manipulator design is proposed, featuring a wider workspace thanks to its mechanical design with multiple degrees of freedom, addressing mobility constraints associated with the trocar. Also, a theoretical study introduces a method to optimize dexterity and dimensions of the surgical robot manipulator while addressing some disadvantages of existing structural design methods, focusing on generating all possible topologies considering design constraints by eliminating isomorphism

Radyoterapide kullanılmak üzere kolimatör mekanizması tasarımı ve geliştirilmesi

This thesis focuses on a Multileaf Collimator design that can shape the beam contour to fit the shape of target geometry and its design improvements. Main purpose of this design is lowering the number of leaves on the multileaf collimator and making the system easier to be controlled. As the Collimator devices undertake the most important point of the beam shaping procedure, ease of control and precision of collimator devices are the major points of operation. As the radiation therapy is one of the most complex and vital medical operations, this thesis started with the deep literature survey that formed the main constraints and goals of the study. Additional constraints and goals were formed after the examination of commercial purpose collimators with respect to their advantageous and disadvantageous sides. Collimator devices either primary or secondary are integratedly used with Linear accelerators thus, linear accelerator devices were taken as another important factor that formed the constraints of design. First design of the collimator mechanism was started with the type and number synthesis. After this procedure, collimator mechanism was decided to be four degree of freedom decoupled manipulator that works in Cartesian coordinate system. After the main design was finished, study of the kinematic analysis of the decoupled mechanism was performed. Due to the fact that radiation therapy robot manipulators carry the collimator mechanisms and motion of the overall system may generate high inertia forces, weight of the collimator mechanism and footprint of the collimator mechanism were also aimed to be reduced. After the first design, upper jaws were modified to be work in polar coordinates instead of cartesian coordinate system. This modification was not only reduced footprint of the device but also reduced scattering issues caused from angular relation between beam and leaf side surface. This modification followed by manufacturing of the first prototype. Examination of the first prototype gave the final shape to the constraints and goals to the collimator design as further advancing in weight and footprint reduction. By using these final constraints second modification was performed to the system and second prototype was manufactured

Motor Performance and Activities of Daily Living in Children with Neurodevelopmental Disorders

Background: Neurodevelopmental disorders (NDDs) are developmental deficiencies that arise due to the damage of the central nervous system in the prenatal, natal, or postnatal period. Objectives: The aim of this study was to evaluate the motor performance and activities of daily living (ADL) and examine their relationship in children with NDDs who do not have physical disabilities. Methods: A total of 107 children who were diagnosed with NDDs, without physical disabilities, and 36 healthy peers between the ages of 4.5 years to 14.5 were included in this study. The subjects' fine and gross motor skills were assessed with Bruininks-Oseretsky test of Motor Performance and ADL with WeeFIM (Functional Independence Measure). Results: Motor performance and ADL were found to be affected in children with NDDs compared to their healthy peers even though they did not have a physical disability. Moderate or low correlations were found amongst 12 of 14 sub-tests of motor performance assessing various activities such as running, balance, coordination, and dexterity, as well as all parameters of WeeFIM in children with NDDs. Children with NDDs with better motor performance had less problems in ADL, were more independent, and had better social cognition and communication skills. Conclusions: Impairments found in motor performance and ADL show that even though children with NDDs, without physical disabilities, seem to be physically unaffected, it can be clearly seen that these children may have problems in coordination, motor control, and balance affecting their daily lives. Consequently, by improving motor performance, independence in ADL may be improved. In the light of these assessments, subjects with NDD's must be included in physiotherapy and rehabilitation and occupational therapy programs in order to address the problems in motor performance and insufficiencies in ADL

Investigating persistent scatterer InSAR (PSInSAR) technique efficiency for landslides mapping: a case study in Artvin dam area, in Turkey

Monitoring and determining landslides in dam reservoirs is very crucial as it is one of the main factors of dam failures in the world. Coruh river basin is one of the most important river basin in the Northeast part of Turkey which accompanies five big dams. Although persistent scatterer InSAR (PSInSAR) method is a powerful remote sensing technique which can measure and monitor displacements of the Earth’s surface over time, its validation is a challenging issue because of the heterogeneous PS data. In this study, the efficiency of PSInSAR is investigated by proposing two different validation methods in order to see the consistency of the determined mean deformation velocities obtained with series of Sentinel-1A SAR-images. In the first method, 3D coordinates of reference points are projected to 1D displacement values in line of sight direction and then compared with the radar displacements of PS points. In the second method, new displacement values of PS points around reference points are identified from an interpolation map in order to be compared with the original displacements of reference points. In the end, it is showed that the displacements found by PSInSAR method are consistent with the reference points’ displacements measured in the study area. Finally, this work’s specific objectives are to present solutions to the challenging validation problem, to show the effectiveness of PSInSAR method and to describe the remaining challenges in PS analysis of landslide applications in dam areas

Effect of aspect ratio and volume fraction of steel fiber on the mechanical properties of SFRC

WOS: 000245498000013In this study, effects of aspect ratio (l/d) and volume fraction (V-f) of steel fiber on the compressive strength, split tensile strength, flexural strength and ultrasonic pulse velocity of steel fiber reinforced concrete (SFRC) were investigated. For this purpose, hooked-end bundled steel fibers with three different l/d ratios of 45, 65 and 80 were used. Three different fiber volumes were added to concrete mixes at 0.5%, 1.0% and 1.5% by volume of concrete. Ten different concrete mixes were prepared. After 28 days of curing, compressive, split and flexural strength as well as ultrasonic pulse velocity were determined. It was found that, inclusion of steel fibers significantly affect the split tensile and flexural strength of concrete accordance with l/d ratio and V-f. Besides, mathematical expressions were developed to estimate the compressive, flexural and split tensile strength of SFRCs regarding l/d ratio and V-f of steel fibers. (c) 2006 Elsevier Ltd. All rights reserved