Fast Stiffness Matrix Calculation for Nonlinear Finite Element Method

We propose a fast stiffness matrix calculation technique for nonlinear finite element method (FEM). Nonlinear stiffness matrices are constructed using Green-Lagrange strains, which are derived from infinitesimal strains by adding the nonlinear terms discarded from small deformations. We implemented a linear and a nonlinear finite element method with the same material properties to examine the differences between them. We verified our nonlinear formulation with different applications and achieved considerable speedups in solving the system of equations using our nonlinear FEM compared to a state-of-the-art nonlinear FEM. © 2014 Emir Gülümser et al

The Sloan Digital Sky Survey Reverberation Mapping Project: Rapid CIV Broad Absorption Line Variability

We report the discovery of rapid variations of a high-velocity CIV broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4sigma) variability in the equivalent width of the broad (~4000 km/s wide) CIV trough on rest-frame timescales as short as 1.20 days (~29 hours), the shortest broad absorption line variability timescale yet reported. The equivalent width varied by ~10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n_e > 3.9 x 10^5 cm^-3. The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios.Comment: 15 pages, 14 figures. Accepted for publication in the Astrophysical Journa

Design of a five-axis ultra-precision micro-milling machine—UltraMill. Part 1: Holistic design approach, design considerations and specifications

High-accuracy three-dimensional miniature components and microstructures are increasingly in demand in the sector of electro-optics, automotive, biotechnology, aerospace and information-technology industries. A rational approach to mechanical micro machining is to develop ultra-precision machines with small footprints. In part 1 of this two-part paper, the-state-of-the-art of ultra-precision machines with micro-machining capability is critically reviewed. The design considerations and specifications of a five-axis ultra-precision micro-milling machine—UltraMill—are discussed. Three prioritised design issues: motion accuracy, dynamic stiffness and thermal stability, formulate the holistic design approach for UltraMill. This approach has been applied to the development of key machine components and their integration so as to achieve high accuracy and nanometer surface finish

İlköğretim öğrencilerinin yaşam kalitesinin toplumsal sınıf değişkeni açısından incelenmesi: Aydın ilinde betimsel bir çalışma

The main purpose of this study is to examine 4th and 5th grade childrens’ quality of life in terms of their social class indicators. Child’s Quality of Life Inventory was used as a data gathering tool in this study. Data were obtained from the study was analyzed in accordance to information about schools’ social economic statues that gathered from The National Education Directorship in Aydın. Number, percentage, frequency, and chi square were used as a statistical method in present study. The finding of the study shows that life quality of children could be mainly revealed with socio economic statues of them. Also the study reveals the most of the children from low socio economic statue are working as a child labor for contributing to the family budget. The most of the families involved in the study explained that they were willing to send their children to the school after the compulsory elementary education. Beside of this finding, some of the families in the sample % 11,9  (n=16)  stated that they were reluctant to send their children to the school after the elementary education. The finding of the study can be considered in terms of public health, school health and general well-being statue of the children in Turkey. ÖzetBu çalışmanın temel amacı Aydın İlinde, ilköğretim 4. ve 5. sınıf öğrencilerinin yaşam kalitesinin sosyo-ekonomik düzey açısından incelenmesidir. Araştırmada veri toplama aracı olarak araştırmacılar tarafından geliştirilen “Çocuk Yaşam Kalitesi Tarama Envanteri” kullanılmıştır. Çalışmada elde edilen veriler, Aydın İl Milli Eğitim Müdürlüğü’nden alınan bilgiler doğrultusunda belirlenen alt, orta ve üst sosyo-ekonomik düzeylerden toplam 6 ilköğretim okulunun 4. ve 5. sınıf öğrencilerinden toplanarak bu veriler üzerinde sayı, yüzde, frekans ve ki kare analizleri gerçekleştirilmiştir. Araştırmanın bulguları, çocuk yaşam kalitesinin büyük oranda sosyo-ekonomik düzey ile açıklanabileceğini göstermektedir. Alt sosyo ekonomik düzeyden çocuklar okul dışında gelir getirici bir iş yaparak aile bütçesine katkıda bulunmaktadırlar. Sosyo-ekonomik düzeyi ne olursa olsun ailelerin çoğunluğu çocuklarının eğitimlerine ilköğretimden sonra da devam etmelerini isterken, alt sosyo-ekonomik düzeydeki okullara devam eden öğrenci ailelerinin %11,9 (n=16)’u “çocuğunun ilköğretimden sonra eğitimine devam etmemesini istemektedir. Tüm bu bulgular, toplum sağlığı, okul sağlığı ve çocuğun genel iyi olma durumu üzerine önemli önlemleri gerekli kılmaktadır.Bu çalışmanın temel amacı Aydın İlinde, ilköğretim 4. ve 5. sınıf öğrencilerinin yaşam kalitesinin sosyo-ekonomik düzey açısından incelenmesidir. Araştırmada veri toplama aracı olarak araştırmacılar tarafından geliştirilen “Çocuk Yaşam Kalitesi Tarama Envanteri” kullanılmıştır. Çalışmada elde edilen veriler, Aydın İl Milli Eğitim Müdürlüğü’nden alınan bilgiler doğrultusunda belirlenen alt, orta ve üst sosyo-ekonomik düzeylerden toplam 6 ilköğretim okulunun 4. ve 5. sınıf öğrencilerinden toplanarak bu veriler üzerinde sayı, yüzde, frekans ve ki kare analizleri gerçekleştirilmiştir. Araştırmanın bulguları, çocuk yaşam kalitesinin büyük oranda sosyo-ekonomik düzey ile açıklanabileceğini göstermektedir. Alt sosyo ekonomik düzeyden çocuklar okul dışında gelir getirici bir iş yaparak aile bütçesine katkıda bulunmaktadırlar. Sosyo-ekonomik düzeyi ne olursa olsun ailelerin çoğunluğu çocuklarının eğitimlerine ilköğretimden sonra da devam etmelerini isterken, alt sosyo-ekonomik düzeydeki okullara devam eden öğrenci ailelerinin %11,9 (n=16)’u “çocuğunun ilköğretimden sonra eğitimine devam etmemesini istemektedir. Tüm bu bulgular, toplum sağlığı, okul sağlığı ve çocuğun genel iyi olma durumu üzerine önemli önlemleri gerekli kılmaktadır

AUDIT STATE DEPENDENT TAXPAYER COMPLIANCE: THEORY AND EVIDENCE FROM COLOMBIA

We develop and analyze a dynamic model of individual taxpayer compliance choice that predicts “audit state dependent taxpayer compliance”, by distinguishing between naïve and myopic behavior versus sophisticated and forward-looking behavior. We then test experimentally the audit state dependent model by reporting the results from the first tax compliance experiment run in Colombia. Consistent with previous studies as well as theoretical predictions, we find that subjects’ compliance rates increase in the audit probability and in the fine rate. We also find more novel results, both theoretically and empirically: fine rates should be increased after an audit to discourage otherwise-increased underreporting, and “nudging” myopic individuals toward reporting a constant rather than a fluctuating proportion of income would benefit both the taxpayer and the tax authority

Polymorphisms of the DNA repair gene XPD (751) and XRCC1 (399) correlates with risk of hematological malignancies in Turkish population

Polymorphisms that occur in DNA repair genes affect DNA repair capacity and constitute a risk factor in hematological malignancies. This study, was aimed to investigate whether xeroderma pigmentosum complementation group D (XPD) and x-ray repair cross-complementing group 1 (XRCC1) gene polymorphisms were involved in the susceptibility to different hematological malignancies. The genotype and allele frequencies were obtained by analyzing XPD gene codon 751 in a total of 80 patients and XRCC1 gene codon 399 polymorphism in a total of 100 patients with hematological malignancies and 100 healthy controls. Mean age was 45 (range: 16 to 75) and 46 (range: 16 to 82) in the patients groups and 39.5 (range: 18 to 67) in the control group, respectively. Additionally, distribution of genotypes and alleles were compared in the patient and control groups. In the comparison of genotype and allele frequencies in hematological malignancies and healthy controls, XPD-751Gln variant was arranged and compared according to age and sex and Gln/Gln genotype was reported to be a protector, which was decreased significantly in acute myeloblastic leukemia (AML) (p = 0.042). No relationship was determined between allele frequencies (p = 0.054). In XRCC1-399, it was shown that Gln/Gln genotype was decreased significantly in AML (p = 0.014) plus all hematological malignancies (p = 0.033) and that Gln allele was present at a lower ratio in AML (p = 0.046). The distribution of polymorphism of both genes was not statistically significant in terms of age and sex. In leukemia with early relapse, XPD 751 Lys/Lys genotype was determined at a statistically higher ratio (p = 0.042). In the evaluation of both genes together, a decrease was noted in Gln/Gln + Lys/Gln haplotype frequency in hematological malignancies (p = 0.048). In this study, it was demonstrated that a decrease in Gln/Gln genotype and Gln allele acted as a protector in XPD codon 751 and XRCC1 codon 399 polymorphisms in acute myeloblastic leukemia (AML) and that an increase in Lys/Lys genotype in acute leukemia was associated with early relapse

Multiple Causes for Delay in Arrival at Hospital in Acute Stroke Patients in Aydin, Turkey

This descriptive, hospital-based study, performed in western Turkey, was designed to assess the level of pre-hospital delay and reasons for such delay in acute stroke patients, taking into consideration certain factors such as socioeconomic status, availability of transport options at onset of symptoms. Data were collected from hospital records, and a questionnaire was administered that included questions about socio-demographics, self-reported risk factors and questions related to hospital arrival. The rate of patients arriving at the hospital more than 3 hours after symptom onset was found to be 31.6% for this study. Approximately 1/3 of patients delayed going to the hospital because they were waiting for symptoms to go away while 1/3 of patients were not aware of the importance of seeking immediate medical help. There was a significant relationship between the use of ambulance transportation and length of time before arrival at the hospitals, though there was no statistically significantly relationship between the existence of stroke risk factors and hospital arrival delay. These results will likely be helpful to health care decision makers as they develop a model for stroke health care and community based training

Dutch Robotics 2011 adult-size team description

This document presents the 2011 edition of the team Dutch Robotics from The Netherlands. Our team gathers three Dutch technical universities, namely Delft University of Technology, Eindhoven University of Technology and University of Twente, and the commercial company Philips. We contribute an adult-size humanoid robot TUlip, which is designed based on theory of the limit cycle walking developed in our earlier research. The key of our theory is that stable periodic walking gaits can be achieved even without high-bandwidth robot position control. Our control approach is based on simultaneous position and force control. For accurate force control, we make use of the Series Elastic Actuation. The control software of TUlip is based on the Darmstadt’s RoboFrame, and it runs on a PC104 computer with Linux Xenomai. The vision system consists of two wide-angle cameras, each interfaced with a dedicated Blackfin processor running vision algorithms, and a wireless networking interface

Dutch Robotics 2010 adult-size team description

This document presents the 2010 edition of the team Dutch Robotics from The Netherlands. Our team gathers three Dutch technical universities, namely Delft University of Technology, Eindhoven University of Technology and University of Twente, and the commercial company Philips. We contribute an adult-size humanoid robot TUlip, which is designed based on theory of the limit cycle walking developed in our earlier research. The key of our theory is that stable periodic walking gaits can be achieved even without high-bandwidth robot position control. Our control approach is based on simultaneous position and force control. For accurate force control, we make use of the Series Elastic Actuation. The control software of TUlip is based on the Darmstadt’s RoboFrame, and it runs on a PC104 computer with Linux Xenomai. The vision system consists of two wide-angle cameras, each interfaced with a dedicated Blackfin processor running vision algorithms, and a wireless networking interface