171 research outputs found

    Using Automatic Differentiation for Adjoint CFD Code Development

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    This paper addresses the concerns of CFD code developers who are facing the task of creating a discrete adjoint CFD code for design optimisation. It discusses how the development of such a code can be greatly eased through the selective use of Automatic Differentiation, and how the software development can be subjected to a sequence of checks to ensure the correctness of the final software

    Algorithm Developments for Discrete Adjoint Methods

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    This paper presents a number of algorithm developments for adjoint methods using the 'discrete' approach in which the discretisation of the non-linear equations is linearised and the resulting matrix is then transposed. With a new iterative procedure for solving the adjoint equations, exact numerical equivalence is maintained between the linear and adjoint discretisations. The incorporation of strong boundary conditions within the discrete approach is discussed, as well as a new application of adjoint methods to linear unsteady flow in turbomachinery

    Different degrees of career success: social origin and graduates’ education and labour market trajectories

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    Most research on social inequalities in higher education (HE) graduates’ labour market outcomes has analysed outcomes at one or two points in time, thus providing only snapshots of graduates’ occupational destinations. This study contributes to the existing literature by examining the education and labour market trajectories of degree holders across their life course and how these trajectories vary by social class of origin. We analyse data from the 1970 British Cohort Study and employ sequence analysis, followed by cluster analysis, to identify HE graduates’ typical trajectories. We assess the degree of social inequalities in the chance of following more or less advantaged pathways from age 16 up to the age of 42 and the extent to which these inequalities are explained by differences in higher education experiences. The results show that graduates from lower social classes of origin have more diverse and less stable trajectories, are less likely to enter top-level jobs in their 20s and more likely to enter and remain in lower social classes than their more socially advantaged counterparts. The age at which people graduate from HE emerges to be a key factor in explaining some of these patterns. Interestingly, HE factors - such as class of degree, fields of study and type of university attended - only partially explain social class differences. Our research provides new insights into the dynamic nature of inequalities among graduates showing that not only does the final destination matter but also the timing and sequencing of spells within the trajectories are important

    One-step preparation of nitrogen doped titanium oxide/Au/reduced graphene oxide composite thin films for photocatalytic applications

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    © The Royal Society of Chemistry 2015. Titanium dioxide (TiO2) and TiO2/Au/reduced graphene oxide (rGO) nanocomposite thin films were grown by ultraviolet matrix assisted pulsed laser evaporation (UV-MAPLE) in controlled O2 or N2 atmospheres. An UV KrF∗ excimer laser (λ = 248 nm, τFWHM ∼ 25 ns, ν = 10 Hz) was used for the irradiation of the MAPLE targets consisting of TiO2 nanoparticles (NPs) or mixtures of TiO2 NPs, Au NPs, and graphene oxide (GO) platelets in aqueous solutions. The effect of Au and GO addition as well as nitrogen doping on the photocatalytic activity of the TiO2 thin films was investigated. The evaluation of the photocatalytic activity was performed by photodegradation of the organic methylene blue model dye pollutant under UV-visible light, >simulated sun> irradiation conditions. Our results show that the photocatalytic properties of TiO2 were significantly improved by the addition of Au NPs and rGO platelets. Nitrogen inclusion into the rGO structure further contributes to the enhancement of the TiO2/Au/rGO nanocomposites photocatalytic activity.The authors thank the financial support of the Executive Unit for Financing Higher Education, Research, Development, and Innovation of the Romanian Ministry of Education and Scientific Research under the contract PN-IIPT-PCCA-2011-3.2-1235 and the Spanish Ministry of Economy and Competitiveness under the contract ENE2014-56109-C3-3-R.Peer reviewedPeer Reviewe

    Implementasi Ketersediaan Beras Dalam Rangka Ketahanan Pangan Di Kabupaten Batang

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    Availability of good rice is expected to maintain food security. However, riceavailability in Batang Regency decreases although the consumption of rice is always increases. When this occurs continuously, it is feared that there will be deficits that cause weak food security.Location of the research was in Badan Pelaksana Penyuluhan dan KetahananPangan Batang Regency. Selection of informants was done using a purposive sampling.To test the quality of the obtained data, technique of triangulation was employed. As the focus of study, implementation of the policy observed through results and process, based on the policy performance of observable indicators of effectiveness, efficiency, fairness, adequacy, responsiveness and accuracy. Based on theories of Edwards III, and Van Meter & Van Horn\u27s implementation model synthesis, acquired the factors that support and hinder the implementation of the policy, namely communications, disposition, bureaucratic structure and resources.Based on the results of this research, implementation of the policy on theavailability of rice on Batang has yet to pan out. There are still weakness in efficiency, fairness and effectiveness.The recommendations are (1) addition of equitable distribution and infrastructures; (2) equity of efforts increased production; (3) equitable socialization and counseling services; (4) monitoring during the production process; and (5) intensive socialization and counseling

    Realtime Video Classification Using Dense HOF/HOG

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    ABSTRACT The current state-of-the-art in Video Classification is based on Bag-of-Words using local visual descriptors. Most commonly these are Histogram of Oriented Gradient (HOG) and Histogram of Optical Flow (HOF) descriptors. While such system is very powerful for classification, it is also computationally expensive. This paper addresses the problem of computational efficiency. Specifically: (1) We propose several speed-ups for densely sampled HOG and HOF descriptors and release Matlab code. (2) We investigate the trade-off between accuracy and computational efficiency of descriptors in terms of frame sampling rate and type of Optical Flow method. (3) We investigate the trade-off between accuracy and computational efficiency for the video representation, using either a k-means or hierarchical k-means based visual vocabulary, a Random Forest based vocabulary or the Fisher kernel

    Is natural orifice specimen extraction surgery really safe in radical surgery for colorectal cancer?

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    Scop: Chirurgia rectală robotică este în prezent o procedură nouă pentru cancerele rectale. Extracția eșantionului cu orificiu natural transanal (NOSE) este o tehnică nouă de îndepărtare a specimenului din cavitatea abdominală prin anus, în loc de o incizie suplimentară după o intervenție chirurgicală colorectală laparoscopică sau robotică. Siguranța NOSE rămâne controversată. Acest studiu și-a propus să investigheze siguranța precoce a NOSE transanal în tratamentul cancerului de colon sigmoid și rectal superior din următoarele aspecte: caracteristici clinice și patologice, indicatori inflamatori și imunitari și complicații postoperatorii. Prezentare de caz: O femeie de 61 de ani, diagnosticată anterior cu cancer rectal, cu antecedente de 6 luni de hematochezie și alternanta diaree-constipatie. Diagnosticul de cancer rectal a fost pus pe baza biopsiei colonoscopice care a confirmat un nodul circumferenţial neregulat de adenocarcinom bine diferenţiat la 10 cm de marginea anală. Rezecția anterioară joasă asistata robotic, urmata de extracția specimenului transanal a fost efectuată după obținerea consimțământului informat. Procedura a fost efectuată cu succes și pacienta a avut o evolutie postoperatorie fără complicații. Diagnosticul patologic postoperator a evidențiat un adenocarcinom moderat diferențiat de 4x4x0,6 cm3 și margine circumferențiala libera. Concluzii: Rezectia de rect robotica plus extractia transanala a specimenului pentru cancerul rectal poate fi efectuata în siguranță și poate fi o abordare eficientă în contrast cu abordarea deschisă sau laparoscopică.Background: Robotic rectal surgery is currently a novel procedure for rectal cancers. Transanal natural orifice specimen extraction (NOSE) is a novel technique to remove the specimen from the abdominal cavity through the anus instead of an additional incision following laparoscopic or robotic colorectal surgery. The safety of NOSE remains controversial. This study aimed to investigate the early safety of transanal NOSE in the treatment of sigmoid colon and upper rectal cancer from the follow aspects: clinical and pathological characteristics, inflammatory and immune indicators and postoperative complications. Case presentation: A 61-year-old women, previously diagnosed with rectal cancer with came 6 months history of hematochezia and altered bowel habit. A diagnosis of rectal cancer was made in view of colonoscopic biopsy which confirmed an irregular circumferential lump of well differentiated adenocarcinoma at 10 cm from the anal verge. Robotic low anterior resection (LAR) plus transanal natural orifice specimen extraction (NOSE) was performed after obtaining informed consent. The procedure was performed successfully and the patient convalesced nicely without any complications. The postoperative pathological diagnosis revealed a 4x4x0.6 cm3 moderately differentiated adenocarcinoma and circumferential clearance. Conclusions: Robotic LAR plus transanal NOSE for rectal cancer can be performed safely and may be an effective approach in contrast to open or laparoscopic approach

    The role of the frozen section examination in the diagnosis of the thyroid nodules

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    Universitatea de Medicină și Farmacie Victor Babeș Timișoara, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Diagnosticul diferențial preoperator sau intraoperator între leziunile tiroidiene benigne și maligne este de o importanță majoră pentru decizia chirurgicală intraoperatorie. Acest studiu analizează corelația dintre rezultatul examenului extemporaneu și rezultatul examinării histopatologice la parafină în cazul nodulilor tiroidieni. Material si metode: Acesta a fost un studiu retrospectiv asupra a 330 de cazuri cu patologie tiroidiană, operate în cadrul Clinicii 2 de Chirurgie a Spitalului Clinic Județean de Urgență Timișoara din 2011 până în 2014, la care s-au efectuat atât examen extemporaneu intraoperator (EXT) cât și examen histopatologic la parafină în cadrul Departamentului de Anatomo-patologie al aceluiași spital. Rezultate: Din cele 330 de cazuri studiate, examenul EXT a stabilit diagnosticul în 244 (73,9%) cazuri și la 86 (26.1%) cazuri diagnosticul a fost incert, cu o sensibilitate de 93,33%, specificitate de 95,81%, în timp ce precizia a ajuns la 95,66%. Două sute douazeci și nouă (84,8%) au fost tumori benigne, iar 15 (27,3%) au fost tumori maligne. La examenul histopatologic, din 86 cazuri incerte 51 (59,3%) au fost benigne, 30 (34,8%) maligne și 5 (5,8%) au ramas neclare. Concluzii: Rezultatele noastre cu metoda EXT sunt echivalente cu cele disponibile în literatura de specialitate cu specificitate, sensibilitate si precizie foarte bune. În cazul în care investigațiile preoperatorii evidențiază noduli unilaterali, EXT a fost util pentru decizia intraoperatorie între lobectomie și tiroidectomie totală, evitând lobectomia inutilă sau reintervenția.Introduction: Preoperative or intraoperative differential diagnosis between benign and malignant thyroid lesions is of utmost importance for the surgical intraoperative decision. This study analyses the correlation between the frozen-section result and the result of the histopathologic paraffin examination in cases of thyroid nodules. Material and methods: This was a retrospective study upon 330 cases with thyroid pathology, operated on in the 2nd Surgical Clinic of the Clinical County Emergency Hospital of Timisoara from 2011 to 2014, that had both intraoperative frozen-section (FS) and postoperative paraffin histologic examination performed by the Pathology Department of the same hospital. Results: Of 330 cases studied, FS examination set the diagnosis in 244 (73.9%) cases and no diagnosis (uncertain) in 86 (26.1%), with a sensitivity of 93.33%, specificity of 95.81%, while accuracy reached 95.66%. Two hundred twenty-nine (84.8%) were benign tumors and 15(27.3%) were malignant tumors. At the histopathologic examination, from 86 uncertain cases 51 (59.3%) were benign, 30(34.8%) malignant and 5 (5.8%) remained unclear. Conclusions: Our results with FS method are equivalent to those available in the literature with very good specificity, sensitivity and accuracy. In cases in which the preoperative investigations show unilateral nodules, FS was still useful for the intraoperative decision between lobectomy and total thyroidectomy, avoiding inutile lobectomy or reoperation

    Intensive laparoscopic laparoscopic training in live tissues – 11 years of experience in Pius Branzeu center from timisoara, Romania

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    Surgical Clinic II , University of Medicine and Pharmacy Timisoara, Romania, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Aims: To assess the effectiveness of intensive laparoscopic training on pigs during 10 years of training. Method: Between 2000 and 2010, 25 intensive (3 days) and 7 advanced (2 days) laparoscopic courses (gastric, biliary, colo-rectal and bariatric) on live tissue were organized, with 324 participants coming from 13 countries. This poster presents the effectiveness of the training of the 244 surgeons who followed the 3 days laparoscopy skills courses. At the beginning of the first day, during the training and at the end of each day the acquirement of the skills participants were evaluated. Three groups where studied: the first group with no experience in laparoscopic surgery; the second group with less than 10 laparoscopic cholecystectomy and the third group with more than 10 laparoscopic cholecystectomy. Results: The first group had a lot of difficulty and were able to acquire only less than 32% of the taught techniques, the second group performed better and acquired 62% of the taught techniques and the third group performed very well acquiring 95% of the taught techniques. Conclusion: Surgeons with no previous laparoscopic surgery experience take little benefit from these courses. They should be encouraged to acquire basic skills on trainer boxes or on virtual reality simulators before the training on pigs. Surgeons with very little experience in laparoscopic surgery acquire important skills, but the best benefit is taken by surgeons with some laparoscopic surgery experience

    Measurement of gauge blocks by interferometry

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    The key comparison EURAMET.L-K1.2011 on gauge blocks was carried out in the framework of a EURAMET project starting in 2012 and ending in 2015. It involved the participation of 24 National Metrology Institutes from Europe and Egypt, respectively. 38 gauge blocks of steel and ceramic with nominal central lengths between 0.5 mm and 500 mm were circulated. The comparison was conducted in two loops with two sets of artifacts. A statistical technique for linking the reference values was applied. As a consequence the reference value of one loop is influenced by the measurements of the other loop although they did not even see the artifacts of the others. This influence comes solely from three "linking laboratories" which measure both sets of artifacts. In total there were 44 results were not fully consistent with the reference values. This represents 10% of the full set of 420 results which is a considerable high number. At least 12 of them are clearly outliers where the participants have been informed by the pilot as soon as possible. The comparison results help to support the calibration and measurement capabilities (CMCs) of the laboratories involved in the CIPM MRA
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