Frame Technique Research Articles

Translation simulation of a cylinder in a horizontal pipe

This article analyses the passive motion of a cylinder driven by flow in a horizontal pipe using the CFD method. In previous study by Yao et al. (2018) [A new openhole multistage hydraulic fracturing system and the ball plug motion in a horizontal pipe. Journal of Natural Gas Science and Engineering, Vol. 50, pp. 11–21], the motion of a cylinder in a horizontal pipe was investigated experimentally. The cylinder was observed contacting with the pipe bottom, meanwhile it behaved like a guided body with its axis parallel to that of the horizontal pipe. Apart from some observations, it was very hard to gain more knowledge about the flow distribution around the cylinder and the role played by the cylinder's eccentricity in the translation. In order to conduct an extended research, this article concentrates on a general model which considers eccentricity and cylinder–pipe interaction. Moreover, a novel yet efficient approach, which investigates the translation process in a control volume attached to the cylinder, is proposed to simulate the motion utilizing the moving reference frame technique. A series of numerical simulations, with various cylinder dimensions and eccentricities, are conducted to investigate the dynamics of the cylinder and fluid. Meanwhile, the validity of the simulations is proved by comparing the results of experiments with the simulations. Lastly, an error analysis is conducted, and the limitations of this study are highlighted.

Tensile testing of single fibres

Glass, flax and aramid fibres are used widely in making composites. These fibres have diameter between 10-20 µm and these are converted to yarn/roving to make woven preforms. Similarly, paper is made from individual cellulose fibres, but in the form of nonwoven mat. Fibres such as flax, jute, viscose and hair are widely used in textile products. These fibres differ greatly in chemical composition, homogeneity and degree of crystallinity. Fibres are solid in nature, but some of them are partly hollow having lumen (flax, pulp) or medulla (hair) in their central axis. Tensile testing of these short length fibres is crucial for many applications, but it is tedious due to their small diameters (>100 µm) and small loads (mN) required for fracture. Paper frame technique adopted to test these single fibres is discussed and corresponding stress-strain diagrams are compared between glass, hair and cellulose fibres. Fractography of these fibres were also carried out using scanning electron microscopy. Nanoindentation was also performed on single fibre cross-sections to measure the modulus. Since the fibres chosen have different packing geometry and crystallinity in different directions, indentation modulus revealed different value compared to tensile modulus. But glass fibre revealed 70 GPa of modulus in both tensile and nanoindentation tests, because it is a isotropic fibre. Tested fibres have strength from anywhere between 200-3000 MPa and elongation ranging from 4% to 45 %. Weibull statistics was also performed and weibull modulus was found to be low for natural fibres compared to man made fibres.

Convergence in nonlinear laser wakefield accelerators modeling in a Lorentz-boosted frame

Laser wakefield acceleration modeling using the Lorentz-boosted frame technique in the particle-in-cell code has demonstrated orders of magnitude speedups. A convergence study was previously conducted in cases with external injection in the linear regime and without injection in the nonlinear regime, and the obtained results have shown a convergence within the percentage level. In this article, a convergence study is carried out to model electron self-injection in a 2D–3V configuration. It is observed that the Lorentz-boosted frame technique is capable of modeling complex particle dynamics with a significant speedup. This result is crucial to curtail the computational time of the modeling of future chains of 10GeV laser wakefield accelerator stages with high accuracy.

American, Indian and Chinese Media on “Belt and Road Initiative”

This research treats contents of newspapers from America, China and India reporting on "Belt and Road Initiative" (BRI) with respect to US, India and China's foreign policies. The study investigates if unlike China, American and Indian press relatively report more 'risk' than 'opportunity' frames on BRI. Detailed literature on risks and opportunity frames is produced through media lenses, underpins regional and global significance and future status of BRI. Comparing framing techniques of The New York Times, Times of India and China Daily, contents of total 60 news articles are quantitatively analyzed. Finally, comparative research paradigm found both Indian and American press framing more risks than opportunities in news, therefore highlighting respective concerns of staying away from the signatory summit of BRI held in Beijing in May 2017.

White Racial Activism and Paper Terrorism: A Case Study in Far-Right Propaganda

ABSTRACTIn 2017, far-right mobilization and demonstrations in the United States were at the highest levels since the 1980s and 90s. This coincided with a marked increase in propaganda campaigns in neighborhoods and across college campuses. Racial activists renewed efforts to rebrand extreme positions, soften racist rhetoric, and grow the movement. The purpose of this case study was to explore the rhetorical content of the propaganda created by one white supremacist. This study contributes to a growing body of literature on far-right propaganda through an examination of common themes, and a comparison of the framing techniques and rhetorical strategies used by other white supremacists.

Commercially Available Mobile Apps for Caregivers of People With Alzheimer Disease or Other Related Dementias: Systematic Search.

BackgroundMore than 15 million Americans provide unpaid care for persons with Alzheimer disease or other related dementias (ADRD). While there is good evidence to suggest that caregivers benefit from psychosocial interventions, these have primarily been delivered via face-to-face individual or group format. Alternatively, offering electronic health (eHealth) interventions may assist caregivers in providing quality care while remaining in good health. Research to date has generated little knowledge about what app features support ADRD caregivers’ behavioral changes and how developers might optimize features over the long term.ObjectiveThere is an evident knowledge gap in the current landscape of commercially available apps, their integration of behavioral techniques, content focus, and compliance with usability recommendations. This paper systematically reviews and inventories the apps caregivers might typically be exposed to and determines the support integrated into the apps and their functionality for older adults.MethodsThe search strategy was designed to mimic typical Web-based health information-seeking behavior for adults. Apps were included based on their explicit focus on ADRD caregiver knowledge and skill improvement. Two coders with expertise in behavioral interventions and eHealth pilot-tested the data extraction. One coder retained app characteristics and design features. Techniques used to promote change were determined, and 2 questions from the Mobile App Rating Scale were used to assess the app credibility and evidence base. Content topics were evaluated using a thematic framing technique, and each app was assessed using a usability heuristic checklist.ResultsThe search results generated 18 unique apps that met the inclusion criteria. Some apps were unavailable, and only 8 unique apps were reviewed. Of the 8, 7 (88%) apps did not state which scientific orientation was followed to develop their content. None of the apps made clinical claims of improving caregivers’ and care recipients’ overall health. All apps relied on textual information to disseminate their contents. None of the apps was trialed and evidence based. Apps included on average 7 out of 10 behavioral change techniques, 5 out of 10 C.A.R.E. (Caregivers, Aspirations, Realities, and Expectations) features, and 10 out of 18 features on the usability heuristics checklist.ConclusionsOur findings suggest that caregivers are likely to discover apps that are not actually accessible and have low or no evidence base. Apps were found to be largely static, text-based informational resources, and few supported behaviors needed to maintain caregivers’ health. While apps may be providing a high volume of information, caregivers must still navigate what resources they need with limited guidance. Finally, the commercial marketplace is addressing some of the major usability elements, but many design elements are not addressed.

Unbalanced synchronous reference frame control of singe-phase stand-alone inverter

This paper presents harmonic damping schemes of the single-phase stand-alone inverter. The unbalanced synchronous reference frame technique is selected to control fundamental frequency voltage at the point of common coupling. The output voltage and the inductor current of the inverter are transformed to the unbalanced synchronous reference frame in which the proportional-integral regulators are used to force the error signals in the dq axes to zero. This control scheme does not require an orthogonal signal generator, and it is equivalent to the ideal proportional-resonant regulator. Harmonic regulators, orders 3rd, 5th, 7th, and 9th are added to minimize the voltage harmonics caused by the connected nonlinear load. The proposed controller is compared with the commonly-used multi-resonant controller. Simulation and experimental results of a 1.5-kVA inverter with the proposed control scheme exhibited excellent harmonic damping of the output voltage, caused by a highly nonlinear load and fast transient performance, which were better than the conventional resonant controller.

Impeller and volute design and optimization of the centrifugal pump with low specific speed in order to extract performance curves

Now a day centrifugal pumps are vital components of industries. Certainly, one of the most important specifications of centrifugal pumps are the performance curves. In the present work, performance curves of a centrifugal pumps are obtained by Computational fluid dynamics (CFD) and as an outcome, CFD results compare by practical curves. At the first step impeller and volute are designed with two standards and at the end former design completed by automatic design process using CFturbo software. For this purpose, full 3D-RANS equations in coupled with SST turbulence model are solved for several flow rate between 20% and 140% of the operation condition by means of a commercial code, CFX. This simulation is defined by means of the multi-reference frame technique in which the impeller is situated in the rotating reference frame, and the volute is in the fixed reference frame. Proposed simulation is based on a steady state flow, non-Newtonian, incompressible and constant property condition. Operation point is simulated to get the total head and then non-operation points are simulated to obtain performance curves. Practical curves and numerical ones are in good agreement, so numerical approach could be a perfect way to make centrifugal pump design better and easier. Indeed pump simulation with CFD approach can increase our knowledge about pump behavior such as consumption energy, trimming process and saving energy before we have any activities on the pump so the predictions have bettering and excise about any process on the pump.

THE GREEN ROOF THERMAL PERFORMANCE EVALUATION IN COMPARISON TO ASBESTOS CEMENT TILES APPLIED TO LIGHT STEEL FRAME BRAZILIAN BUILDINGS

This research aimed at comparing the thermal performance provided in experimental modules, one of which was performed with conventional cover, made of asbestos cement tiles; an another with green cover. The structure of the studied modules was executed using Light Steel Frame technique. As an experimental research, modules were built in a wide place, without the interference of shading. Instruments were installed in the inner part of the modules to measure the following data: air temperature, relative humidity. From the collected data, representative episodes have been chosen for the studies that aimed to compare the comfort provided by both modules, built with different roofs. As result, it was verified that the module with green roof had better performance than the module covered with asbestos cement tile in all selected episodes. The module covered with green roof maintained lower internal temperature variation throughout the days, indicating that the green roof has characteristic thermal insulation, reducing the heat flow from the roof.

Supersymmetric action for multiple D0-brane system

We have constructed a complete action for the system of N D0-branes in flat 10D type IIA superspace. It is invariant under the rigid spacetime supersymmetry and local worldline supersymmetry (κ-symmetry). This latter can be considered as supersymmetry of maximal 1d SU(N) SYM model which is made local by coupling to supergravity induced by embedding of the center of energy worldline into the target superspace. The spinor moving frame technique is essentially used to achieve such a coupling. We discuss the differences with Panda-Sorokin multiple 0-brane action and with the dimensionally reduced 11D multiple M-wave action.

Measuring Actual Payment for Biodiversity Protection

Abstract I report the results of an experiment using a convenience sample of subjects recruited on Amazon Mechanical Turk that examines how religiously and scientifically framed messages about biodiversity loss influence a choice to make donations to protect against biodiversity loss. Subjects who received a religiously framed message were just as likely to make a donation as participants who read a control or scientifically framed message about biodiversity loss. In a subsample of Christians, the religiously framed message did not influence people to make a donation, compared to a control message, while a scientifically framed message increased the likelihood of making a donation. A religiously framed message increased donation amount in Christians, relative to a control message. Because there is a cost associated with biodiversity loss and protection, this research is important to determine how different message framing techniques promote action to prevent further biodiversity loss.

Modeling, Simulation and Analysis of Induction Motor for Electric Vehicle Application

High power induction motor (IM) is widely used in industries and recently has been put into electric vehicle as the replacement of the internal combustion engine. In order to study the characteristics of the IM, a model of three-phase squirrel cage induction motor is designed and developed using MATLAB Simulink tool. Synchronous reference frame (SRF) technique is implemented to simplify the equivalent circuit model. Based on state space form, a flux linkage equation is developed using three stages transformation matrices. It demonstrated a good performance with fast response for AC start-up test, where simulated induced torque, rotor speed, mechanical output power, efficiency, slip and stator current waveforms were generated accordingly. Indeed, the developed IM model can be used as a starting platform to further study and analyses the IM drives performance for electric vehicle application.

Aerodynamic design of multi-propeller/wing integration at low Reynolds numbers

Based on the detailed flow characteristics analyses of a base four-propeller/wing integration at a low Reynolds number of 3.0×105, new multi-propeller/wing integrated aerodynamic design philosophy and methodology have been developed and validated numerically. The core of the present design philosophy is to make good use of coupling effects between two adjacent propellers to realize the low-Reynolds-number flow-field reconstruction, thus to improve the aerodynamic performance of the multi-propeller/wing integration at the operating power-on state. The multi-reference frame (MRF) technique which quasi-steadily solves the Reynolds-averaged Navier–Stokes (RANS) equations coupled with transition model is used to design the example four-propeller/wing integration at a low Reynolds number of 3.0×105. As a result, the designed multi-propeller/wing integration yields a maximum lift-to-drag ratio of 72.81, which represents a 21.08% increase compared to the base four-propeller/wing integration.

Global geometrical optics method for vector-valued Schrödinger problems

We extend the theory of global geometrical optics method, proposed originally for the linear scalar high-frequency wave-like equations in [Commun. Math. Sci., 2013, 11(1): 105-140], to the more general vector-valued Schrodinger problems in the semi-classical regime. The key ingredient in the global geometrical optics method is a moving frame technique in the phase space. The governing equation is transformed into a new equation but of the same type when expressed in any moving frame induced by the underlying Hamiltonian flow. The classical Wentzel-Kramers-Brillouin (WKB) analysis benefits from this treatment as it maintains valid for arbitrary but fixed evolutionary time. It turns out that a WKB-type function defined merely on the underlying Lagrangian submanifold can be obtained with the help of this moving frame technique, and from which a uniform first-order approximation of the wave field can be derived, even around caustics. The general theory is exemplified by two specific instances. One is the two-level Schrodinger system and the other is the periodic Schrodinger equation. Numerical tests validate the theoretical results.

The Analysis on Income of Beef Cattle Breeders in Various Crop Patterns in Umbulsari District, Jember Regency

The objective of research is: (1) to analyze the cost incurred at integrated farming involving beef cat-tle breeding and various crop patterns; (2) to estimate the revenue received from the integrated farm-ing involving beef cattle breeding and various crop patterns; (3) to find out the income obtained from the integrated farming involving beef cattle breeding and various crop patterns; and (4) to acknowledge the balance of revenue and cost of the integrated farming involving beef cattle breeding and various crop patterns. Research was located in Umbulsari District, Jember Regency, starting from 16 June 2016 to 28 September 2016. Sampling frame technique used in this research is Two-Stage Cluster Sampling. Both sampel and location of research are determined with purposive sampling. The analytical model of research is the analysis on cost and revenue of livestock-crop farming. Research indicates some results. (1) Crop Pattern 5, which cultivates sugarcane only, and beef cattle breeding have produced the heaviest cost of all combinations observed, especially if measured in terms of per hectare and per livestock unit. The cost for this crop pattern is IDR 96,750,000.- while the cost for beef cattle breeding is IDR 10,865,000.-. Total cost of both works attains IDR 107,615,000.-. The reason behind this huge cost is that Crop Pattern 5 involves high production cost to cover the costs of land processing, land lease, and organic fertilizer; (2) Crop Pattern 5 has produced the highest reve-nue. The revenue of this crop pattern per hectare is IDR 110,450,000.- while beef cattle breeding per livestock unit gives revenue at IDR 14,900,000.-. Total revenue then is around IDR 125,350,000.-; (3) The income obtained from Crop Pattern 5 is IDR 13,700,000.- whereas beef cattle breeding deliv-ers income around IDR 4,035,000.-. Total income is then IDR 17,735,000.-. (4) The highest balance between revenue and cost is 1.82 and it is found at Crop Pattern 4.

Performance comparison of two whole genome amplification techniques in frame of multifactor preimplantation genetic testing

PurposeTo compare multiple displacement amplification and OmniPlex whole genome amplification technique performance during array comparative genome hybridization (aCGH), Sanger sequencing, SNaPshot and fragment size analysis downstream applications in frame of multifactor embryo preimplantation genetic testing.MethodsPreclinical workup included linked short tandem repeat (STR) marker selection and primer design for loci of interest. It was followed by a family haplotyping, after which an in vitro fertilization preimplantation genetic testing (IVF-PGT) cycle was carried out. A total of 62 embryos were retrieved from nine couples with a confirmed single gene disorder being transmitted in their family with various inheritance traits—autosomal dominant (genes—ACTA2, HTT, KRT14), autosomal recessive (genes—ALOX12B, TPP1, GLB1) and X-linked (genes—MTM1, DMD). Whole genome amplification (WGA) for the day 5 embryo trophectoderm single biopsies was carried out by multiple displacement amplification (MDA) or polymerase chain reaction (PCR)-based technology OmniPlex and was used for direct (Sanger sequencing, fragment size analysis, SNaPshot) and indirect mutation assessment (STR marker haplotyping), and embryo aneuploidy testing by array comparative genome hybridization (aCGH).ResultsFamily haplotyping revealed informative/semi-informative microsatellite markers for all clinical cases for all types of inheritance. Indirect testing gave a persuasive conclusion for all embryos assessed, which was confirmed through direct testing. The overall allele dropout (ADO) rate was higher for PCR-based WGA, and MDA shows a better genomic recovery scale. Five euploid embryos were subjected to elective single embryo transfer (eSET), which resulted in four clinical pregnancies and birth of two healthy children, which proved free of disease causative variants running in the family postnataly.ConclusionsA developed multifactor PGT protocol can be adapted and applied to virtually any genetic condition and is capable of improving single gene disorder preimplantation genetic testing in a patient-tailored manner thus increasing pregnancy rates, saving costs and increasing patient reliability.

Frameless robot-assisted stereoelectroencephalography in children: technical aspects and comparison with Talairach frame technique.

OBJECTIVE Robot-assisted stereoelectroencephalography (SEEG) is gaining popularity as a technique for localization of the epileptogenic zone (EZ) in children with pharmacoresistant epilepsy. Here, the authors describe their frameless robot-assisted SEEG technique and report preliminary outcomes and relative complications in children as compared to results with the Talairach frame-based SEEG technique. METHODS The authors retrospectively analyzed the results of 19 robot-assisted SEEG electrode implantations in 17 consecutive children (age < 17 years) with pharmacoresistant epilepsy, and compared these results to 19 preceding SEEG electrode implantations in 18 children who underwent the traditional Talairach frame-based SEEG electrode implantation. The primary end points were seizure-freedom rates, operating time, and complication rates. RESULTS Seventeen children (age < 17 years) underwent a total of 19 robot-assisted SEEG electrode implantations. In total, 265 electrodes were implanted. Twelve children went on to have EZ resection: 4 demonstrated Engel class I outcomes, whereas 2 had Engel class II outcomes, and 6 had Engel class III-IV outcomes. Of the 5 patients who did not have resection, 2 underwent thermocoagulation. One child reported transient paresthesia associated with 2 small subdural hematomas, and 3 other children had minor asymptomatic intracranial hemorrhages. There were no differences in complication rates, rates of resective epilepsy surgery, or seizure freedom rates between this cohort and the preceding 18 children who underwent Talairach frame-based SEEG. The frameless robot-assisted technique was associated with shorter operating time (p < 0.05). CONCLUSIONS Frameless robot-assisted SEEG is a safe and effective means of identifying the EZ in children with pharmacoresistant partial epilepsy. Robot-assisted SEEG is faster than the Talairach frame-based method, and has equivalent safety and efficacy. The former, furthermore, facilitates more electrode trajectory possibilities, which may improve the localization of epileptic networks.

A novel surgical technique for a rat subcutaneous implantation of a tissue engineered scaffold

ObjectivesSubcutaneous implantations in small animal models are currently required for preclinical studies of acellular tissue to evaluate biocompatibility, including host recellularization and immunogenic reactivity. MethodsThree rat subcutaneous implantation methods were evaluated in six Sprague Dawley rats. An acellular xenograft made from porcine pericardium was used as the tissue-scaffold. Three implantation methods were performed; 1) Suture method is where a tissue-scaffold was implanted by suturing its border to the external oblique muscle, 2) Control method is where a tissue-scaffold was implanted without any suturing or support, 3) Frame method is where a tissue-scaffold was attached to a circular frame composed of polycaprolactone (PCL) biomaterial and placed subcutaneously. After 1 and 4 weeks, tissue-scaffolds were explanted and evaluated by hematoxylin and eosin (H&E), Masson’s trichrome,Picrosirius Red, transmission electron microscopy (TEM), immunohistochemistry, and mechanical testing. ResultsMacroscopically, tissue-scaffold degradation with the suture method and tissue-scaffold folding with the control method were observed after 4 weeks. In comparison, the frame method demonstrated intact tissue scaffolds after 4 weeks. H&E staining showed progressive cell repopulation over the course of the experiment in all groups with acute and chronic inflammation observed in suture and control methods throughout the duration of the study. Immunohistochemistry quantification of CD3, CD 31, CD 34, CD 163, and αSMA showed a statistically significant differences between the suture, control and frame methods (P < 0.05) at both time points. The average tensile strength was 4.03 ± 0.49, 7.45 ± 0.49 and 5.72 ± 1.34 (MPa) after 1 week and 0.55 ± 0.26, 0.12 ± 0.03 and 0.41 ± 0.32 (MPa) after 4 weeks in the suture, control, and frame methods; respectively. TEM analysis showed an increase in inflammatory cells in both suture and control methods following implantation. ConclusionRat subcutaneous implantation with the frame method was performed with success and ease. The surgical approach used for the frame technique was found to be the best methodology for in vivo evaluation of tissue engineered acellular scaffolds, where the frame method did not compromise mechanical strength, but it reduced inflammation significantly.

Introducing the windowed Fourier frames technique for obtaining the approximate solution of the coupled system of differential equations

This paper is devoted to introduce an efficient solver using a combination of the symbol of the operator and the windowed Fourier frames (WFFs) of the coupled system of second order ordinary differential equations. The given system has a basic importance in modeling various phenomena like, Cascades and Compartment Analysis, Pond Pollution, Home Heating, Chemostats and Microorganism Culturing, Nutrient Flow in an Aquarium, Biomass Transfer and others. The proposed method reduces the system of differential equations to a system of algebraic equations in the coefficients of WFFs. The introduced method is computer oriented with highly accurate solution. To demonstrate the efficiency of the proposed method, two examples are presented and the results are displayed graphically. Finally, we convert the presented coupled systems of BVPs to a first order system of ODEs to compare the obtained numerical solution with those solutions using the fourth-order Runge–Kutta method (RK4).

Mitigating divestment stigma: a legitimation perspective

PurposeForeign divestment (FD) has often different roles such as being a corporate diversification strategy, and of such divestment may have effects on a company’s image and reputation. Ongoing businesses trends including internationalization, deregulation and diversification have forced executives to exploit image and reputation as strategic corporate resources, which make them the target of a firm’s active management. The paper aims at developing the understanding of the framing techniques of discursive legitimation and of the strategies used by companies when signalizing their FD decision.Design/methodology/approachTo examine the framing strategies used by companies to legitimize their FD decisions, the authors used the case study methodology using a critical discursive analysis. Using companies’ press releases regarding FD of Western multinational companies (MNCs), the authors examined for the specific frame used in each release. After identification through initial coding, the dominant frames were recognized by recording patterns in technique, content, themes, patterns of keywords, quotes and semantic method.FindingsThis study demonstrated that legitimation is an integral part of framing press release. Companies framing of their FD decisions can be interpreted as an attempt to not only prevent negative repercussion from stakeholders but also to legitimize the FD decisions to protect the company’s image and reputation.Originality/valueBy examining the elements of FD press releases, the authors uncovered the microelements of the framing techniques used by MNCs to legitimize their decision.