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The purpose of this work is to test the effectiveness of strengthening timber structures by means of composite bars. This article presents the results of preliminary tests carried out on solid beams made of fir wood. The test specimens, which are classified as strength class C24, had dimensions of 7 × 17 × 330 cm. Beams were reinforced with 8 mm diameter basalt fiber-reinforced polymer (BFRP) bars. The bars were glued into grooved channels along the bottom surface. Epoxy resin was used as an adhesive. The strength tests were conducted in accordance with the requirements of EN 408+A1:2012. The four-point bending scheme was adopted. The tests were conducted in the following two series: unreinforced beams (A) and beams reinforced with composites (B). Five elements were tested in each series. The reinforcement resulted in an average increase in the bending moment value of 8.41%. The deflection value at failure increased by 19.77%. The work also includes an analysis of the failure mode and a ductility analysis. Further tests should be carried out using a higher reinforcement ratio. A higher reinforcement ratio should make the presented reinforcement configuration more effective. [ABSTRACT FROM AUTHOR]

This article discusses the software tool (Simscape—Multibody program of MATLAB) primarily intended for dynamic and kinematic processes with practical applications in static calculations. Currently, there are few published scientific works utilizing this tool for tasks like basic static calculations of truss systems. We were interested in comparing the calculation using the tools we use in our work and research activities for theoretical calculation; the potential reliance on simulations in the future could help to avoid the necessity of complex theoretical calculations, which can be time-consuming and prone to errors. Despite the fact that the structure may appear simple, in practice, there may not always be time for a verification calculation in the theoretical field (proper model creation, inclusion of all conditions, etc.). The beam system is intentionally both externally and internally statically indeterminate. For this reason, it is logically necessary to also consider deformation conditions. The achieved results were interesting in terms of accuracy compared to SOLIDWORKS, which was used for computation verification. Through very simple optimization, we were able to further increase the calculation accuracy without complicating other parameters. [ABSTRACT FROM AUTHOR]

Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Textile Composites is a resin system containing a textile fiber, yarn, or fabric system for special properties. Cord knit is a simple and economic and fast technique for producing tubular textile fabrics. This article studied the effect of some variables such as outer layer yarn count and core material of poly-amide cord knitted fabrics on its properties and applying it as a cord-knitted composite bar for reinforcing concrete. six samples with two different outer layer yarn counts (1200 and 2400 denier) and three different core materials (polyamide, fiberglass, and polyethylene 50%, and polypropylene 50%) were produced and tested, then inserted in epoxy to convert to a composite cord. The properties of composite cord knitted fabrics were tested. Then different numbers of bars were used (one bar, two bars, and three bars) from the highest properties cord knitted poly-amide composite fabrics for reinforcing concrete beams (50 cm*10cm*10cm), flexure of those beams were tested and it was found that using two bars from poly-amide composite has the highest effect on reinforcing concrete beams. [ABSTRACT FROM AUTHOR]

This article discusses the software tool (Simscape—Multibody program of MATLAB) primarily intended for dynamic and kinematic processes with practical applications in static calculations. Currently, there are few published scientific works utilizing this tool for tasks like basic static calculations of truss systems. We were interested in comparing the calculation using the tools we use in our work and research activities for theoretical calculation; the potential reliance on simulations in the future could help to avoid the necessity of complex theoretical calculations, which can be time-consuming and prone to errors. Despite the fact that the structure may appear simple, in practice, there may not always be time for a verification calculation in the theoretical field (proper model creation, inclusion of all conditions, etc.). The beam system is intentionally both externally and internally statically indeterminate. For this reason, it is logically necessary to also consider deformation conditions. The achieved results were interesting in terms of accuracy compared to SOLIDWORKS, which was used for computation verification. Through very simple optimization, we were able to further increase the calculation accuracy without complicating other parameters.

The purpose of this work is to test the effectiveness of strengthening timber structures by means of composite bars. This article presents the results of preliminary tests carried out on solid beams made of fir wood. The test specimens, which are classified as strength class C24, had dimensions of 7 × 17 × 330 cm. Beams were reinforced with 8 mm diameter basalt fiber-reinforced polymer (BFRP) bars. The bars were glued into grooved channels along the bottom surface. Epoxy resin was used as an adhesive. The strength tests were conducted in accordance with the requirements of EN 408+A1:2012. The four-point bending scheme was adopted. The tests were conducted in the following two series: unreinforced beams (A) and beams reinforced with composites (B). Five elements were tested in each series. The reinforcement resulted in an average increase in the bending moment value of 8.41%. The deflection value at failure increased by 19.77%. The work also includes an analysis of the failure mode and a ductility analysis. Further tests should be carried out using a higher reinforcement ratio. A higher reinforcement ratio should make the presented reinforcement configuration more effective.

The commercialization of modular timber products as cost-effective and lightweight components has resulted in innovative engineering products, e.g., glued laminated timber, laminated veneer lumber, I-beams, cross-laminated timber and solid timber joined with wedge joints. With the passage of time, timber structures can deteriorate, or new structural elements are required to increase the stiffness or load-bearing capacity in newly built structures, e.g., lintels over large-scale glazing or garages, or to reduce cross-sectional dimensions or save costly timber material while still achieving low weight. It is in such cases that repair or correct reinforcement is required. In this experimental and numerical study, the static performance of flexural timber beams reinforced with prestressed basalt BFRP, glass GFRP and hybrid glass–basalt fiber bars is shown. The experimental tests resulted in an increase in the load-carrying capacity of BFRP (44%), GFRP (33%) and hybrid bars (43%) and an increase in the stiffness of BFRP (28%), GFRP (24%) and hybrid bars (25%). In addition to this, glued laminated timber beams reinforced with prestressed basalt rods subjected to biological degradation, 7 years of weathering and prolonged exposure to various environmental conditions were examined, and an increase in the load-bearing capacity of 27% and an increase in stiffness of 28% were obtained. In addition, full-size laminated timber beams reinforced with prestressed basalt bars were investigated in the field as an exploratory test under fire conditions at elevated temperatures, and the effect of the physical–mechanical properties during the fire was examined via an analysis of these properties after the fire. In addition, a satisfactory correlation of the numerical simulations with the experimental studies was obtained. The differences were between 1.1% and 5.5%. The concordance was due to the fact that, in this study, the Young, Poisson and shear moduli were determined for all quality classes of sawn timber. Only a significant difference resulted in the numerical analysis for the beams exposed to fire under fire conditions. The experimental, theoretical and numerical analyses in this research were exploratory and will be expanded as directions for future research. [ABSTRACT FROM AUTHOR]

The use of composite precast or steel bars as reinforcements for timber beams is an important technique that can improve effectiveness or allow cross sections to be reduced. This paper presents experimental, theoretical, and numerical studies of full-size timber beams measuring 82 × 162 × 3650 mm3 using prestressed steel bars and 10 mm diameter basalt and glass bars with a prestress of 10 MPa. In addition, parametric studies were carried out using FEM numerical simulations. In the experimental tests, an increase in load-bearing capacity and stiffness of up to 58% and 10.7% for steel bars, 32% and 10.1% for basalt bars, and 27% and 7.8% for glass bars, respectively, was obtained compared to unreinforced beams. The different levels of improvement in reinforcement efficiency was also related to the different elastic modulus of the reinforcement itself. Unreinforced beams showed a linear elastic range. In contrast, on beams reinforced with steel bars, the curve had a slightly steeper line than the control beam, and the slope of the curve then decreased when a certain load was reached. All beams failed when the lower wood fibers reached maximum tensile strain. The allowable compressive strain then decreased by 36.6% for basalt bars, 32.9% for glass bars, and 30.4% for steel bars. The use of prestressing further exploited the strength of the reinforcement beyond the yield point. All unreinforced beams primarily failed in the tension zone due to fracture of the timber fibers. Prestressed and reinforced beams were already failing due to bending and shear. The experimental and numerical analysis was also compared, and the results showed a good agreement and a maximum difference of approximately 5.7%. [ABSTRACT FROM AUTHOR]

Purpose. Peer crowd-targeted campaigns are a novel approach to engage high-risk young adults in tobacco use prevention and cessation. We elicited the perspectives of young adult key informants to understand how and why two social branding interventions were effective: (1) "COMMUNE," designed for "Hipsters" as a movement of artists and musicians against Big Tobacco, and (2) "HAVOC," designed for "Partiers" as an exclusive, smoke-free clubbing experience. Design. Qualitative study (27 semistructured qualitative phone interviews). Setting. Intervention events held in bars in multiple U.S. cities. Participants: Twenty-seven key informants involved in COMMUNE or HAVOC as organizers (e.g., musicians, event coordinators) or event attendees. Measures. We conducted semistructured, in-depth interviews. Participants described intervention events and features that worked or did not work well. Analysis. We used an inductive-deductive approach to thematically code interview transcripts, integrating concepts from intervention design literature and emergent themes. Results: Participants emphasized the importance of fun, interactive, social environments that encouraged a sense of belonging. Anti-tobacco messaging was subtle and nonjudgmental and resonated with their interests, values, and aesthetics. Young adults who represented the intervention were admired and influential among peers, and intervention promotional materials encouraged brand recognition and social status. Conclusion. Anti-tobacco interventions for high-risk young adults should encourage fun experiences; resonate with their interests, values, and aesthetics; and use subtle, nonjudgmental messaging.

Meandering channels display complex planform configurations with upstream (US)‐ and downstream (DS)‐skewed bends. Bend orientation is linked to hydrodynamics, bed morphodynamic regime, bank characteristics, riparian vegetation, and geological environment, which are the modulating factors that act specially in high‐amplitude and high‐sinuosity conditions. Based on the interaction between hydrodynamics and morphodynamics, previous studies have suggested that sub‐ (β < βR) and super‐resonant (β > βR) morphodynamic regimes (where β is the half width‐to‐depth ratio of the channel, and βR is the resonance condition) may trigger a particular bend orientation (upstream‐ and downstream‐skewed, respectively). However, natural rivers exhibit both US‐skewed and DS‐skewed bend patterns along the same reach, independently of the morphodynamic regime. Little is known about the hydrogeomorphology (forced and free morphodynamic patterns) under these bend orientations. Herein, using the asymmetric Kinoshita laboratory channel, experiments under sub‐ and super‐resonant conditions (with presence or absence of free bars) for upstream‐and downstream‐skewed conditions are performed. The experiments with migrating bars (β = 10, 15) are compared with previous experiments where only migrating dunes (β = 2) under sub‐resonant condition were observed. Additional, detailed field measurements at US‐ and DS‐skewed bends of different skewness along the Tigre River in Peru are also presented. Conditions at field scale filter out the influence of the morphodynamic regime in high‐sinuosity and high amplitude bends, where nonlinear processes (width variation, bedform dynamics) can directly affect the development of the three‐dimensional flow structure, and consequently the erosional and depositional patterns, and the lateral migration patterns. Plain Language Summary: Meandering rivers develop bends that are oriented upstream‐ and downstream‐valley. Laboratory experiments in a meandering channel and field measurements in the Tigre River show that downstream oriented bends produce larger depositional points bars along the inner bank, and more developed secondary flows throughout the bend; therefore, downstream oriented bends migrate at faster rates than upstream oriented bends. Key Points: Downstream‐skewed bends tend to produce larger point bars than upstream‐skewed bendsDownstream‐skewed bends generate more developed and mature bedforms and tend to migrate faster than upstream‐skewed bendsAt field scale, nonlinear processes can filter out the effect of the morphodynamic regime on the development of US‐ and DS‐skewed bends [ABSTRACT FROM AUTHOR]

PurposeTo evaluate the impact of a Social Branding intervention in bars and nightclubs on smoking behavior.DesignQuasi-experimental controlled study.SettingBars and nightclubs in San Diego and San Francisco (intervention) and Los Angeles (control).Participants"Hipster" young adults (age 18-26) attending bars and nightclubs.InterventionAnti-tobacco messages delivered through monthly anti-tobacco music/social events, opinion leaders, original art, direct mail, promotional activities, and online media.MeasuresA total of 7240 surveys were collected in 3 cities using randomized time location sampling at baseline (2012-2013) and follow-up (2015-2016); data were analyzed in 2018. The primary outcome was current smoking.AnalysisMultivariable logistic regression assessed correlates of smoking, adjusting for covariates including electronic cigarette use; differences between cities were evaluated using location-by-time interactions.ResultsSmoking in San Francisco decreased at a significantly faster rate (51.1%-44.1%) than Los Angeles (45.2%-44.5%) (P = .034). Smoking in San Diego (mean: 39.6%) was significantly lower than Los Angeles (44.8%, P < .001) at both time points with no difference in rate of change. Brand recall was not associated with smoking behavior, but recall was associated with anti-tobacco attitudes that were associated with smoking.ConclusionThis is the first controlled study of Social Branding interventions. Intervention implementation was accompanied by decreases in smoking (San Francisco) and sustained lower smoking (San Diego) among young adult bar patrons over 3 years.

Behaviorally Anchored Rating Scales or BARS have been used to measure teaching effectiveness in different stages, programs, and instruction modalities. The author's purpose in this article is twofold: to examine, to date, the use of BARS in the educational setting for the assessment of teacher performance and to demonstrate the possibilities of using this type of instruments in the near future. To do so, the author examines the publications on this issue by conducting a systematic literature review in two distinct phases. In the first phase, queries of different key terms are made in the Web of Science (WOS) database. This is followed by a second phase in which the title, abstract, and keywords of each publication are manually examined. The findings reveal an increase in the use of BARS in recent years providing evidence on the high potential for application of this type of instrument for the appraisal of teaching effectiveness. The author concludes that research on the use of BARS for the evaluation of teacher performance is not only an emerging line of study, but also a topic that invites the academic community to reflect on which mechanisms are most appropriate when dealing with a serious task, in the context of educational organization, such as the appraisal of teaching effectiveness. The originality of this work lies in being the first systematic literature review on the use of BARS for the assessment of teacher performance in the educational setting. [ABSTRACT FROM AUTHOR]

Damage often develops in glued laminated timber members under high bending loads due to natural defects in the timber, which results in their low load-bearing capacity and stiffness. In order to improve the bending mechanical properties of glulam beams, a new type of longitudinal glulam reinforcement with pre-stressed basalt fibre-reinforced polymer composites (BFRP) was developed using the Near Surface Mounted (NSM) technique. The strengthening method consisted of two pre-stressed BFRP bars glued into the grooves at the bottom side of the beam; meanwhile, for the second strengthening alternative, the third BFRP bar was embedded into the groove at the top side of the beam. Therefore, an experimental study was carried out to verify this strengthening technique, in which fifteen full-size timber beams were tested with and without bonded BFRP bar reinforcement in three series. According to the results of this experimental study, it can be seen that the effective load-bearing capacity of the reinforced beams increased up to 36% and that the stiffness of the beams increased by 23% compared to the unreinforced beams. The tensile stresses in the wooden fibres were reduced by 11.32% and 25.42% on average for the beams reinforced with two and three BFRP bars, respectively. On the other hand, the compressive stresses were reduced by 16.53% and 32.10% compared to the unreinforced beams. The usual failure mode saw the cracking of the wood fibres at the defects, while for some specimens, there were also signs of cracks in the epoxy adhesive bond; however, the crack propagation was, overall, significantly reduced. The numerical calculations also show a good correlation with the experimental results. The difference in the results between the experimental and numerical analysis of the reinforced and unreinforced full-sized beams ranged between 3.63% and 11.45%. [ABSTRACT FROM AUTHOR]

Triassic strata of the Tecovas and Trujillo formations in the Palo Duro Canyon of West Texas record deposition dominated throughout by upper‐flow‐regime channel flow. These strata provide an opportunity for new insights into the architecture, floodplain/channel processes, vertical profiles, palaeohydrology and taphonomy typical of broader upper‐flow‐regime‐dominated fluvial systems. Thicker channel‐fills (ca 2 m, aspect ratio ca 24) host upper‐plane‐bed, symmetrical antidune, breaking‐antidune, chute‐and‐pool, and cyclic‐step structures. The thinner channel‐fill population (<1 m, aspect ratio ca 35) comprises upper‐plane‐bed and some antidune structures. Some of the larger channel fills developed low‐angle downstream‐accreting bars, with rare examples of laterally accreting side‐attached bars. This appears to be the first documentation of an ancient upper‐flow‐regime side‐attached bar. Lamina orientation of structures parallel accretion surfaces because these followed the original bed surface, and structures drop in flow regime down the bar surfaces as formative Froude numbers also declined. A generalized vertical sequence for large upper‐flow‐regime channel storeys has upper‐plane‐bed structures above the basal scour, transitioning upward into higher flow regime structures (for example, antidunes, cyclic steps, etc.), then back to a mix of upper‐plane‐bed and antidunes or lower‐flow‐regime structures towards the top. The Tecovas Formation and overlying Trujillo Sandstone both bear layers of cross‐cutting laterally amalgamated valley fills, multivalleys, and are separated by a regional sequence boundary. Calculated palaeodischarges for Tecovas (ca 90 m3/s) and Trujillo (ca 76 m3/s) rivers record flow at the stage where symmetrical antidunes were deposited. These discharges occurred at some point on the falling limb of a flood hydrograph of currently unknown shape. Slopes for the rivers were on the order of 10−4 to 10−5, consistent with typical continental‐interior rivers. Large and flashy discharge was, thus, the likely cause for supercritical‐flow conditions instead of excessive slopes. Rivers in both the Tecovas and Trujillo formations record a fluvial system developed in a tropical to subtropical megamonsoonal environment. The tendency for preservation of metre‐scale channel‐fills and catastrophic inundations of floodplains and lakes in single floods has also made the Dockum Group a prolific preserver of large Triassic vertebrates. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to develop a nutraceutical product, in bars, using defatted Brazil nut by-products. The methodological bases of analyses followed the guidelines of the Association of Official Analytical Chemists international and experimental tests of formulations. The bars presented with high protein content with high nutraceutical potential expressed as high levels of magnesium, sodium, calcium and potassium, with emphasis on selenium, supplying around 50% of the daily recommendations. The sulfur amino acids reach approximately the recommended chemical score (97%), the aromatic amino acids with a proportion close to 50% and those of the branched chain supplying the established recommendations for adults. In the sensory tests, the formulation that presented the best attributes and the greatest acceptance (91.78% for the flavor and 97.89% for the general impression) by the tasters was the bar formulation made with a 75:25 ratio of defatted Brazil nuts flour and isolated soy protein. [ABSTRACT FROM AUTHOR]

Smoke-free policies prevent exposure to secondhand smoke and encourage tobacco cessation. Local smoke-free policies that are more comprehensive than statewide policies are not allowed in states with preemption, including Oklahoma, which has the sixth highest smoking prevalence in the United States. In states with preemption, voluntary smoke-free measures are encouraged, but little research exists on venue owners' and managers' views of such measures, particularly in nightlife businesses such as bars and nightclubs. This article draws from semistructured interviews with 23 Oklahoma bar owners and managers, examining perceived risks and benefits of adopting voluntary smoke-free measures in their venues. No respondents expressed awareness of preemption. Many reported that smoke-free bars and nightclubs were an inevitable societal trend, particularly as younger customers increasingly expected smoke-free venues. Business benefits such as decreased operating and cleaning costs, improved atmosphere, and employee efficiency were more convincing than improved employee health. Concerns that voluntary measures created an uneven playing field among venues competing for customers formed a substantial barrier to voluntary measures. Other barriers included concerns about lost revenue and fear of disloyalty to customers, particularly older smokers. Addressing business benefits and a level playing field may increase support for voluntary smoke-free nightlife measures.

This article focuses on the effect of nano-silica on an epoxy matrix of hybrid basalt-carbon fiber reinforced polymers (FRP) composites. Usage of this type of bar continues to grow in the construction industry. The corrosion resistance, strength parameters, and easy transport to the construction site are significant parameters compared to traditional reinforcement. The research for new and more efficient solutions resulted in the intensive development of FRP composites. In this paper, scanning electron microscopy (SEM) analysis of two types of bars is proposed: hybrid fiber-reinforced polymer (HFRP) and nanohybrid fiber-reinforced polymer (NHFRP). HFRP, in which 25% of the basalt fibers were replaced with carbon fibers, is more mechanically efficient than basalt fiber reinforced polymer composite (BFRP) alone. In HFRP, epoxy resin was additionally modified with a 3% SiO2 nanosilica admixture. Adding nanosilica to the polymer matrix can raise the glass transition temperature (Tg) and thus shift the limit beyond which the strength parameters of the composite deteriorate. SEM micrographs evaluate the surface of the modified resin and fiber–matrix interface. The analysis of the previously conducted tests—shear and tensile at elevated temperatures—correlate with the microstructural SEM observations with the obtained mechanical parameters. This is a summary of the impact of nanomodification on the microstructure–macrostructure of the FRP composite. [ABSTRACT FROM AUTHOR]

In the last few years, fiber-coupled diode lasers have shown massive applications in many fields of communication and scientific research. Particularly, the pumping of solid-state lasers is a key application for more powerful diode lasers enabling good solutions in various laser micro methods like metal cutting, sintering, structuring as well as drilling. In this work, a simple beam shaping method is demonstrated for coupling a high-power semiconductor laser diode into multi-mode fiber optic using optical lenses. The optical lenses as beam transformation components are utilized to reshape the asymmetrical irradiation of the diode laser bar and to circularize the laser beam. Using this simple method, compact, high-outputpower, and high-brightness fiber-coupled laser diode systems are achieved. The obtained results show that the entire optical coupling efficiency of the system is more than 65%. [ABSTRACT FROM AUTHOR]

Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implantologie is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of composite precast or steel bars as reinforcements for timber beams is an important technique that can improve effectiveness or allow cross sections to be reduced. This paper presents experimental, theoretical, and numerical studies of full-size timber beams measuring 82 × 162 × 3650 mm3 using prestressed steel bars and 10 mm diameter basalt and glass bars with a prestress of 10 MPa. In addition, parametric studies were carried out using FEM numerical simulations. In the experimental tests, an increase in load-bearing capacity and stiffness of up to 58% and 10.7% for steel bars, 32% and 10.1% for basalt bars, and 27% and 7.8% for glass bars, respectively, was obtained compared to unreinforced beams. The different levels of improvement in reinforcement efficiency was also related to the different elastic modulus of the reinforcement itself. Unreinforced beams showed a linear elastic range. In contrast, on beams reinforced with steel bars, the curve had a slightly steeper line than the control beam, and the slope of the curve then decreased when a certain load was reached. All beams failed when the lower wood fibers reached maximum tensile strain. The allowable compressive strain then decreased by 36.6% for basalt bars, 32.9% for glass bars, and 30.4% for steel bars. The use of prestressing further exploited the strength of the reinforcement beyond the yield point. All unreinforced beams primarily failed in the tension zone due to fracture of the timber fibers. Prestressed and reinforced beams were already failing due to bending and shear. The experimental and numerical analysis was also compared, and the results showed a good agreement and a maximum difference of approximately 5.7%.

Magnetic particle imaging (MPI) is a radiation-free vessel- and target-imaging modality that can sensitively detect nanoparticles. A static magnetic gradient field, referred to as a selection field, is required in MPI to provide a field-free region (FFR) for spatial encoding. The image resolution of MPI is closely related to the size of the FFR, which is determined by the selection field gradient amplitude. Because of the limitations of existing gradient coil hardware, the image resolution of MPI cannot satisfy the clinical requirements of human in vivo imaging. Pulsed excitation has been confirmed to improve the image resolution of MPI by breaking down the ‘relaxation wall.’ This work proposes the use of a pulsed waveform magnetic gradient from magnetic resonance imaging to further improve the image resolution of MPI. Through alignment of the gradient direction along the field-free line (FFL), each location on the FFL is able to have a unique excitation field strength that generates a specific relaxation-induced decay signal. Through excitation of nanoparticles on the FFL with many gradient profiles, a high-resolution, one-dimensional (1D) image can be reconstructed on the FFL. For larger magnetic nanoparticles, simulation results revealed that a pulsed excitation field with a greater flat portion generates a 1D bar pattern phantom image with a higher correlation and spatial resolution. With parallel FFL and gradient coil movements, high-resolution, two-dimensional (2D) Shepp–Logan phantom and brain vessel maps were reconstructed through repetition of the spatially resolved measurement of magnetic nanoparticles on the FFL. [ABSTRACT FROM AUTHOR]

Aluminum alloy BS.1476-HE.15 by virtue of its high strength and low density finds application in the form of bars or sections for cranes, bridges, and other such structures where a reduction in dead weight load and inertia stresses is advantageous. Bars and sections in H.15 alloy are mostly produced by extrusion. Some material processed this way has been prone to exfoliation corrosion. Extended aging for 24 h at a temperature of 185 °C (365 °F) virtually suppresses the tendency for exfoliation corrosion to develop. Also, the use of a sprayed coating, either of aluminum or Al-1Zn alloy, was effective in halting and preventing this form of attack. While alarming, the appearance of exfoliation corrosion provides a valuable warning to the engineer or inspector before a severe weakening of the particular sections has occurred. [ABSTRACT FROM AUTHOR]

The die cast rotor bars in production squirrel cage induction motors (SCIMs) are easily subjected to porosity or other defects in production, which considerably affects the motors’ reliability and efficiency in operation. Planar flux sensing coils have been investigated for the defect detection of SCIM rotor. However, these types of sensors cannot accurately evaluate the severity of porosity or broken bar. This article develops a novel instrument to inspect and quantitatively analyze the rotor quality of SCIM. The sensor consists of the electromagnetic flux sensing coils directly from an SCIM stator. By injecting a dc voltage at phases A and B of the sensor, the induced voltage signal is generated from phase C. A quantitative fault indicator (QFI) is constructed on the basis of the instrument voltage output. The variation trend of the QFI with respect to fault severity is investigated by establishing a theoretical sensor model. Experimental results indicate that the proposed method can accurately detect the porosity and broken bar, and evaluate their severities for the die cast rotor. The developed solution can be easily implemented with low cost and computational complexity, which can achieve real-time inspection of SCIM rotor in theline. [ABSTRACT FROM AUTHOR]

Despite its importance for assessing the effectiveness of communicating information visually, fine-grained recallability of information visualisations has not been studied quantitatively so far. In this work, we propose a question-answering paradigm to study visualisation recallability and present VisRecall — a novel dataset consisting of 200 visualisations that are annotated with crowd-sourced human (N = 305) recallability scores obtained from 1,000 questions of five question types. Furthermore, we present the first computational method to predict recallability of different visualisation elements, such as the title or specific data values. We report detailed analyses of our method on VisRecall and demonstrate that it outperforms several baselines in overall recallability and FE-, F-, RV-, and U-question recallability. Our work makes fundamental contributions towards a new generation of methods to assist designers in optimising visualisations. [ABSTRACT FROM AUTHOR]

Past studies have shown that when a visualization uses pictographs to encode data, they have a positive effect on memory, engagement, and assessment of risk. However, little is known about how pictographs affect one’s ability to understand a visualization, beyond memory for values and trends. We conducted two crowdsourced experiments to compare the effectiveness of using pictographs when showing part-to-whole relationships. In Experiment 1, we compared pictograph arrays to more traditional bar and pie charts. We tested participants’ ability to generate high-level insights following Bloom’s taxonomy of educational objectives via 6 free-response questions. We found that accuracy for extracting information and generating insights did not differ overall between the two versions. To explore the motivating differences between the designs, we conducted a second experiment where participants compared charts containing pictograph arrays to more traditional charts on 5 metrics and explained their reasoning. We found that some participants preferred the way that pictographs allowed them to envision the topic more easily, while others preferred traditional bar and pie charts because they seem less cluttered and faster to read. These results suggest that, at least in simple visualizations depicting part-to-whole relationships, the choice of using pictographs has little influence on sensemaking and insight extraction. When deciding whether to use pictograph arrays, designers should consider visual appeal, perceived comprehension time, ease of envisioning the topic, and clutteredness. [ABSTRACT FROM AUTHOR]

A short period of steady-state asynchronous operation after loss of excitation can improve the reliability of turbogenerator. The rotor damping structure of the turbogenerator can provide asynchronous torque and, thus, play an important role in improving the asynchronous operating ability. The rotor slot wedges as a part of rotor damping structure often made of aluminum, beryllium bronze, or stainless steel. The different materials of the rotor slot wedges can affect not only the asynchronous operating ability of the turbogenerator but also the rotor losses. The selection of material for the rotor slot wedges is therefore a key factor that should be carefully considered in the design of turbogenerator. In this article, the effect of the rotor slot wedges made of different materials on the asynchronous operating ability, rotor loss densities, and loss distributions of the turbogenerator after loss of excitation is investigated by time-stepping finite element model. The variations of the asynchronous operating ability and the rotor losses are revealed along with the rotor slot wedge conductivity. The rotor regions where the losses are significantly affected by the rotor slot wedge material are obtained. The results provide theoretic basis for improvement of the asynchronous operating ability and reduction of the rotor loss of turbogenerator. [ABSTRACT FROM AUTHOR]

Soft robots made from soft materials show great advantages over rigid robots in environmental adaptability and motion flexibility. However, too soft body makes them lose the load capacity, which limits their applications in locomotion. Although the crawling tensegrity robots with both rigid bars and flexible cables are potential to address this challenge, the existing inchworm friction drive methods are difficult to realize the motion of a single tensegrity unit. Besides, the lack of appropriate soft actuators and robot configuration also blocks the development of the crawling tensegrity robots. This article presents a new inchworm driving method realized by the inclined supporting feet. By using the twisted artificial muscle (TAM) as actuator, the combination of the TAM and the inclined supporting feet endows a single three-bar tensegrity unit with multimotion capacity and anisotropic stiffness characteristics. The designed tensegrity robot not only has high compliance but also displays high stiffness, which endows it with high load capacity. The prototype can carry a load of 150 g (7.5 times of its weight) to achieve straight and turning motions. This article provides a design idea for the crawling tensegrity robot and a theoretical foundation for improving the load capacity of high compliance robots. [ABSTRACT FROM AUTHOR]

Antioverload high-range accelerometer is playing an increasingly important role in the field of hard target penetration testing, and the demand of higher accuracy and higher range accelerometers is growing consequently. Therefore, a novel accelerometer with a new structure of membrane island is proposed in this article, while the measurement range is significantly improved to 200 000 g. The design is mainly based on the finite-element method. In general, the membrane-island structured piezoresistive accelerometer is formed of a four-clamped membrane that carries a piezoresistor at the four ends. The four piezoresistors form a Wheatstone bridge. Then, based on the Timoshenko plate and shell theory, a mathematical stiffness model of the four-clamped membrane is established. The detailed parameters of the sensor are carried out by the finite-element analysis (FEA) and optimization, and it has a maximum stress of 26.8 MPa and a maximum displacement of $0.208~\mu \text{m}$ when applying an input acceleration of 200 000 g. Finally, the sensitivity test, antioverload test, and dynamic test of three membrane-island structured prototypes are carried out, and their sensitivities are 0.579, 0.505, and $0.532~\mu \text{V}$ /g, respectively; the passband with 5% dynamic error is 14.9, 16.5, and 15.8 kHz, respectively. The accelerometer has an antioverload capability of 250 000 g, which is verified by the Hopkinson bar. The test results show that this membrane-island structured accelerometer has both good antioverload capability and high accuracy. [ABSTRACT FROM AUTHOR]

Referencing objects of interest is a common requirement in many collaborative tasks. Nonetheless, accurate object referencing at a distance can be challenging due to the reduced visibility of the objects or the collaborator and limited communication medium. Augmented Reality (AR) may help address the issues by providing virtual pointing rays to the target of common interest. However, such pointing ray techniques can face critical limitations in large outdoor spaces, especially when the environment model is unavailable. In this work, we evaluated two pointing ray techniques for distant object referencing in model-free AR from the literature: the Double Ray technique enhancing visual matching between rays and targets, and the Parallel Bars technique providing artificial orientation cues. Our experiment in outdoor AR involving participants as pointers and observers partially replicated results from a previous study that only evaluated observers in simulated AR. We found that while the effectiveness of the Double Ray technique is reduced with the additional workload for the pointer and human pointing errors, it is still beneficial for distant object referencing. [ABSTRACT FROM AUTHOR]

The evaluation of teaching effectiveness in blended learning methodologies is usually carried out using Likert-type questionnaires; however, instruments with Behavioral Anchored Rating Scales (BARS) are sometimes employed for this purpose. This paper examines the validity and reliability of an instrument with BARS designed to assess teaching effectiveness in blended learning environments, within the university setting. The research involves a sample of 1436 students from a medium size university in Spain. Using this sample (n = 1436), the authors carry out a psychometric study that consists of four phases: (1) comprehension validity analysis, (2) construct validity analysis, (3) confirmation of construct validity, and (4) analysis of the instrument reliability. The findings provide satisfactory values for all the parameters analyzed (for instance: Variance explained = 77.61%; RMSEA = 0.042; or Cronbach's alpha = 0.956), indicating that the BARS instrument examined is perfectly valid and reliable for the appraisal of teaching effectiveness in blended learning methodologies. The authors conclude that this paper fills an important gap in the literature by presenting an instrument that, thanks to the use of behavioral scales, facilitates this task in the university context. [ABSTRACT FROM AUTHOR]

This article proposes a new high-fidelity simulation model of an induction motor (IM) based on finite-element analysis (FEA). The proposed model enables fast and accurate IM simulation with the inverter circuit model and control algorithm. That is, the proposed model can represent non-ideal features of IM, such as magnetic saturation, spatial harmonics, skew, and saturation-induced saliency in high accuracy. To construct the proposed model, a dq equivalent circuit of the squirrel cage rotor is introduced. Based on this, the static FEA is conducted which can accelerate the model construction compared to the conventional time-stepping FEA technique. Then, a flux-based IM model is established, which has advantages on speed, accuracy, and memory size in the simulation. To verify the effectiveness of the proposed model, the models are constructed for two commercial IMs used for the industrial drive. IM control algorithms are tested in various operating conditions on the proposed model. The results are compared with the time-stepping FEA and the experiment for the verification of the proposed model. [ABSTRACT FROM AUTHOR]

Gas-insulated switchgear (GIS) might withstand ac/lightning impulse (LI) superimposed voltage caused by lightning intrusion or switching operation during operation. When there are insulation defects, the breakdown probability is greatly increased, which threatens the safety of GIS and needs to be further studied. In this study, the discharge characteristics of two typical insulation defects, including a metallic protrusion on bus bar and foreign matter attached to insulator, under ac/LI superimposed voltage were studied, and the influence of superimposed phase, polarity, and ratio was investigated. It was found that, under a quasi-uniform electric field, the superimposed breakdown voltage (${U}_{s}$) was the same as the LI breakdown voltage (${U}_{\text {LI}}$). However, when there were insulation defects, ${U}_{s}$ was significantly affected by the superimposed phase and polarity. For the metallic protrusion, the most critical condition was an −LI superimposed at $\varphi =90$ , with ${U}_{s}$ decreasing by 11% relative to ${U}_{\text {LI}}$. For the metallic particle attached to insulator, when an +LI was superimposed at $\varphi = 0^{\circ }$ or −LI at $\varphi = 180^{\circ }$ , ${U}_{s}$ decreased most, by as much as 19.6% relative to ${U}_{\text {LI}}$. Finally, the validation test was performed in a 110-kV GIS with insulation defects and ${U}_{s}$ was 7%–14% lower than ${U}_{\text {LI}}$. The results showed that, under a proper superimposed phase and polarity, ${U}_{s}$ could be significantly lower than ${U}_{\text {LI}}$ of GIS with insulation defects, indicating the great potential of the ac/LI superimposed voltage test for the high-sensitive detection of GIS insulation defects. [ABSTRACT FROM AUTHOR]

Data visualization design has a powerful effect on which patterns we see as salient and how quickly we see them. The visualization practitioner community prescribes two popular guidelines for creating clear and efficient visualizations: declutter and focus. The declutter guidelines suggest removing non-critical gridlines, excessive labeling of data values, and color variability to improve aesthetics and to maximize the emphasis on the data relative to the design itself. The focus guidelines for explanatory communication recommend including a clear headline that describes the relevant data pattern, highlighting a subset of relevant data values with a unique color, and connecting those values to written annotations that contextualize them in a broader argument. We evaluated how these recommendations impact recall of the depicted information across cluttered, decluttered, and decluttered+focused designs of six graph topics. Undergraduate students were asked to redraw previously seen visualizations, to recall their topics and main conclusions, and to rate the varied designs on aesthetics, clarity, professionalism, and trustworthiness. Decluttering designs led to higher ratings on professionalism, and adding focus to the design led to higher ratings on aesthetics and clarity. They also showed better memory for the highlighted pattern in the data, as reflected across redrawings of the original visualization and typed free-response conclusions, though we do not know whether these results would generalize beyond our memory-based tasks. The results largely empirically validate the intuitions of visualization designers and practitioners. The stimuli, data, analysis code, and Supplementary Materials are available at https://osf.io/wes9u/. [ABSTRACT FROM AUTHOR]