19672 research outputs found
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Investigation of tendon dynamics effects on tension leg platform response in random seas
No full textThis study investigated tendon dynamics effects of tension leg platform models with tendons modelled by finite element spring and beam elements for uncoupled and coupled tension leg platform in random waves and current environment. The purpose of the study is to proffering numerical solution of single mathematical equation of motion for fully integrated-coupled tension leg platform floater with tendons model. Structural modelling of complete tension leg platform is achieved with the help of ABAQUS/Standard finite element tools which is incorporated with ABAQUS/Aqua module for the application of hydrodynamic loadings on the partially submerged tension leg platform hull and fully submerged platform tendons. For the uncoupled tension leg platform model, weight, inertia, hydrodynamic force and damping forces are ignored on the tendons modelled with springs, while the stiffness of the tendons is considered as a static restoring force. The coupled tension leg platform model had all the forces applied on the tendons modelled with beam elements. Conclusively, modelling and analysis of the tension leg platform as uncoupled and coupled models have expanded our understanding to know that surge motion response is fairly predicted by the two models, however, heave and pitch motions, and variations in tendon tension differ significantly; hence, coupled tension leg platform model is recommended. The influence of a removed tendon due to accident or maintenance on the tension leg platform motions is also reported. © IMechE 2018
Using bootstrapped quantile regression analysis for small sample research in applied linguistics: Some methodological considerations
No full textQuantitative applied linguistics research often takes place in restricted settings of an intact language classroom, workplace, phonetics laboratory or longitudinal sample. In such settings the samples tend to be small, which raises several methodological problems. The main aim of the current paper is to give a detailed explanation of methodological and practical implications inherent in a robust statistical method called bootstrapped quantile regression (BQR) analysis. Importantly for applied linguistics research, the BQR method could help to deal with methodological difficulties inherent in small sample studies. The current study employed a moderately small sample (N = 27) of students learning the Japanese language in a Malaysian public university. It examined the relationships between the students’ language learning motivation (specifically, integrative orientation), the students’ images or stereotypes about Japan and their global attitudes toward the target language country and its people. The findings indicated that there was a statistically significant relationship between the students’ attitudes toward the target language country and their integrative orientation. In addition, these attitudes were found to be the most constant determinant of the integrative orientation. Besides the applied linguistics research, the BQR method can be used in a variety of the human sciences research where a sample size is small. © 2019 Nikitina et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Correlation among the nuclear structure and effective symmetry energy of finite nuclei
No full textThe structural evolution and correlation of ground state properties with the effective nuclear matter characteristics for the even-even isotopes of Th and U nuclei are investigated within axially and triaxially deformed Relativistic-Hartree-Bogoliubov approaches. The density dependent meson exchange (DD-ME), point coupling (DD-PC)and non-linear (NL3 ⁎ )force parameters are used for the present analysis. The potential energy surface is calculated by the quadratic constraint method to analyze the structural evolution by mean of shape transitions over an isotopic chain. The Coherent Density Fluctuation Model is used to formulate the nuclear matter characteristics such as symmetry energy and neutron pressure by weightening the density for finite nuclei. Further, we have predicted the possible modes of decay (α-decay and/or β-decay)in order to understand the stability of these nuclei. The calculated results are compared with experimental and other theoretical models, wherever available. We found a peak for effective symmetry energy and neutron pressure at N=150 for all the force parameters, which may correlate with the shell/sub-shell closures in an isotopic chain. © 2019 Elsevier B.V
The physicochemical and biomechanical profile of forsterite and its osteogenic potential of mesenchymal stromal cells
Get PDFIt has been demonstrated that nanocrystalline forsterite powder synthesised using urea as a fuel in sol-gel combustion method had produced a pure forsterite (FU) and possessed superior bioactive characteristics such as bone apatite formation and antibacterial properties. In the present study, 3D-scaffold was fabricated using nanocrystalline forsterite powder in polymer sponge method. The FU scaffold was used in investigating the physicochemical, biomechanics, cell attachment, in vitro biocompatibility and osteogenic differentiation properties. For physicochemical characterisation, Fourier-transform infrared spectroscopy (FTIR), Energy dispersive X-ray (EDX), X-ray diffraction (XRD), Raman spectroscopy, Xray photoemission spectrometer (XPS) and Brunauer-Emmett-Teller (BET) were used. FTIR, EDX, XRD peaks and Raman spectroscopy demonstrated correlating to FU. The XPS confirmed the surface chemistry associating to FU. The BET revealed FU scaffold surface area of 12.67 m(2)/g and total pore size of 0.03 cm(3)/g. Compressive strength of the FU scaffold was found to be 27.18 +/- 13.4 MPa. The human bone marrow derived mesenchymal stromal cells (hBMSCs) characterisation prior to perform seeding on FU scaffold verified the stromal cell phenotypic and lineage commitments. SEM, confocal images and presto blue viability assay suggested good cell attachment and proliferation of hBMSCs on FU scaffold and comparable to a commercial bone substitutes (cBS). Osteogenic proteins and gene expression from day 7 onward indicated FU scaffold had a significant osteogenic potential (p < 0.05), when compared with day 1 as well as between FU and cBS. These findings suggest that FU scaffold has a greater potential for use in orthopaedic and/or orthodontic applications
Pattern Matching for DNA Sequencing Data Using Multiple Bloom Filters
No full textStoring and processing of large DNA sequences has always been a major problem due to increasing volume of DNA sequence data. However, a number of solutions have been proposed but they require significant computation and memory. Therefore, an efficient storage and pattern matching solution is required for DNA sequencing data. Bloom filters (BFs) represent an efficient data structure, which is mostly used in the domain of bioinformatics for classification of DNA sequences. In this paper, we explore more dimensions where BFs can be used other than classification. A proposed solution is based on Multiple Bloom Filters (MBFs) that finds all the locations and number of repetitions of the specified pattern inside a DNA sequence. Both of these factors are extremely important in determining the type and intensity of any disease. This paper serves as a first effort towards optimizing the search for location and frequency of substrings in DNA sequences using MBFs. We expect that further optimizations in the proposed solution can bring remarkable results as this paper presents a proof of concept implementation for a given set of data using proposed MBFs technique. Performance evaluation shows improved accuracy and time efficiency of the proposed approach. © 2019 Maleeha Najam et al
Noncentrosymmetric Sulfide Oxide MZnSO (M = Ca or Sr) with Strongly Polar Structure as Novel Nonlinear Crystals
No full textWe performed a comprehensive ab inito calculation to investigate the influence of substitution of Ca2+ (180 pm) by larger Sr2+ (200 pm) in MZnSO (M = Ca or Sr) on the structural properties and, hence, on the linear and nonlinear optical properties. The substitution of Ca2+ by Sr2+ in MZnSO causes a band gap reduction resulting in an influence on the photophysical properties and enhances the optic activity toward the visible region. The observation of linear optical properties reveals a band gap reduction on moving from Ca to Sr, and the whole spectral structure shifts toward lower energies. The substitution of Ca2+ by Sr2+ introduces an obvious enhancement in the anisotropy between the extraordinary and ordinary tensor components, as confirmed by the uniaxial anisotropy and birefringence favoring an important role in second harmonic generation (SHG) and optical parameter oscillator due to better fulfilling of phase-matching conditions. The calculations show that SrZnSO exhibits larger SHG and microscopic first hyperpolarizability (βijk) than CaZnSO. © 2019 American Chemical Society
Reliability and validity of a taekwondo electronic body protector
No full textThe Protector and Scoring System was introduced in taekwondo to encourage transparency in scoring during competition. The system, which has been used in the past two Olympics, consists of two main components, the electronic body protector and socks. The few studies that have been conducted on the Protector and Scoring System have not been comprehensive and used questionable testing methods. The main objectives of this study were to methodologically examine the validity and reliability of a Protector and Scoring System body protector. To fulfil these objectives, a customized mechanical pendulum was built to test the Protector and Scoring System. The reliability of the pendulum was first determined by tracking the pendulum’s mean velocity at impact for 50 trials on two separate occasions. Data from both days were compared and showed no significant differences (p = 0.08). Mean kinetic energy of the pendulum was then calculated to be 55.52 J. For the experimental trial, the electronic body protector was divided into 12 sections. Each section was tested with the pendulum for 50 trials on two separate days. It was found that only three sections had no significant differences between the two days (p > 0.01), while the rest of the sections had significantly different readings between Day 1 and Day 2. Based on the homologous descriptive statistics, only two sections were in the same group, which translated to the Protector and Scoring System being only 16.7% reliable overall for both days. In terms of validity, an independent samples t-test was used to determine the differences between the calculated kinetic energy from the pendulum (the criterion) and the displayed kinetic energy on the Protector and Scoring System, and values were found to be significantly different (p < 0.01). Overall, the reliability and validity of the Protector and Scoring System was found to be questionable. The system needs to be examined exhaustively before being used in any future tournaments. © IMechE 2018
A Comparative Study of Two Modalities in Pain Management of Patients Presenting with Chronic Brachial Neuralgia
No full textObjectives: The study aims to assess, evaluate, and compare the efficacy of acupressure and hypnotherapy in the management of pain in patients presenting with chronic brachial neuralgia (CBN). Design: Randomized controlled trial. Settings/location: Department of Orthopaedic Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. Subjects: Forty patients with CBN following traumatic brachial plexus injury from 2012 to 2017. Intervention: Therapy for a duration of 1 month in two groups; subjects in the hypnotherapy group received a weekly session of clinical hypnotherapy (total of four times) using a standardized protocol, while subjects in the acupressure group were guided by an acupuncturist during the initial session, received 2 month take home supply of acupressure patches, and were reviewed fortnightly. Outcome measures: The Visual Analog Scale, the Brief Pain Inventory, and the SF-36v2® Health Survey were recorded at different time points; 1 month pretreatment (week 0), pretreatment (week 4), post-Treatment (week 8), and 4 months post-Treatment (week 20). Results: There was a statistically significant improvement in the average pain intensity from pretreatment to post-Treatment score in both groups. The pain intensity increased 4 months later; however, the pain intensity was still significantly reduced in comparison with pretreatment scores. The study suggests that both treatment outcomes are effective in terms of alleviating pain and improving quality of life in subjects with CBN, to a different degree. Conclusion: Overall, both therapies were able to improve the pain intensity and quality of life significantly during the treatment period. Hypnotherapy was observed to have a better carryover effect compared to acupressure, especially in terms of improving quality of life and the mental component score. © Copyright 2019, Mary Ann Liebert, Inc., publishers 2019
Application of image quality assessment module to motion-blurred wood images for wood species identification system
No full textDespite tighter conservation regulations, demand for timber products has continued to increase due to growing population. Normally, experts identify the wood species based on the pattern of the wood surface texture. However, manual inspection on wood texture is tedious, time-consuming, impractical and cost-ineffective for a human to analyze a large number of timber species. Therefore, a reliable automatic wood recognition system is needed in order to classify the wood species efficiently. The proposed system includes image acquisition, image quality assessment module (IQA), image deblurring, feature extraction and classification. In this research, the wood images are motion-blurred due to imperfections in the imaging and capturing process. Hence, an IQA module is proposed to monitor the quality of images before proceeding to the next stage which is the feature extraction process. The IQA module will determine whether the image has to undergo the image deblurring process based on the image quality value. If the image is of low quality based on the image quality value obtained, then the image will be deblurred before the feature extraction procedure. A reliable motion deblurring technique, which is based on Lucy–Richardson algorithm, is employed to enhance the motion-blurred images before proceeding to the next stage, which is the feature extraction process. Then, a statistical feature extraction technique is proposed to extract 24 features from each wood image. Finally, a support vector machine is used to classify the 20 tropical wood species. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Change management framework to support uml diagrams changes
No full textAn effective change management technique is essential to keep track of changes and to ensure that software projects are implemented in the most effective way. Unified Modeling Language (UML) diagrams are widely adopted in software analysis and design. UML diagrams are divided into different perspectives in modelling a problem domain. Preserving the consistency among these diagrams is very crucial so that they can be updated continuously to reflect software changes. In this research, a change management framework is proposed to trace the dependency and to determine the effect of the change in UML diagrams incrementally after each update operation. A set of 45 change impact and traceability analysis templates for all types of change in UML diagrams elements are proposed to detect the change affected and to maintain the diagrams consistency and integrity. The proposed framework is modeled and simulated using Coloured Petri Nets (CPNs) formal language. UML is powerful in describing the static and dynamic aspects of systems, but remains semi-formal and lacks techniques for models validation and verification especially if these diagrams updated continuously. Formal specifications and mathematical foundations such as CPNs are used to automatically validate and verify the behavior of the model. A new structure is proposed for the mutual integration between UML and CPNs modeling languages to support model changes. © 2019, Zarka Private University. All rights reserved