Effects Of Design Features Research Articles

Computational modeling of braided venous stents — Effect of design features and device-tissue interaction on stent performance

Designing venous stents with desired properties is challenging due to the partly conflicting performance criteria, e.g., enhancing flexibility may be at odds with increasing patency. To evaluate the effect of design parameters on the mechanical performance of braided stents, computational simulations are performed using finite element analysis. Model validation is performed through comparison with measurements. Considered design features are stent length, wire diameter, pick rate, number of wires, and stent end-type, being either open-ended or closed looped. Based on the requirements of venous stents, tests are defined to study the effect of design variations with respect to the following key performance criteria: chronic outward force, crush resistance, conformability, and foreshortening. Computational modeling is demonstrated to be a valuable tool in the design process through its ability of assessing sensitivities of various performance metrics to the design parameters. Additionally, it is shown, using computational modeling, that the interaction between a braided stent and its surrounding anatomy has a significant impact on its performance. Therefore, taking into account device-tissue interaction is crucial for the proper assessment of stent performance.

Effects of design features: The determinant for hospital performance in southwest, Nigeria

This study examined the effects of design features on the user as a determinants for hospital performance in Southwest, Nigeria. The design features to proactively improve the hospital environment should be put in place to increase the hospital performance and users ’satisfaction. This study was carried out at the first generation Federal University Teaching Hospitals (FUTH) in southwest, Nigeria. Methodologically, it employed mixed methods of data collection. The primary source involves the use of multiple-choice structured questionnaire to collect data from the sample population. Also, semi-structured interview (SSI) was used to support the information gathered through the questionnaire in the study area. Sample size which amounted to 575 respondents and were randomly taken from the staff, inpatients and outpatients across the FUTH. However, Respondents were asked to rate the design features such as cleanness of the healthcare environment, natural lighting and ventilation, design for regular hygiene and handwashing policy, noise level within the environment and ward spaces, adequate air quality within wards, offices, and treatment spaces, location of the nursing station to oversee patients without obstructions and design for spatial flexibility and adaptability in order of preferences as a major determinants for hospital building performance.

Friends from the Future: A Scoping Review of Research into Robots and Computer Agents to Combat Loneliness in Older People.

Background and AimLoneliness is a common problem in older adults and contributes to poor health. This scoping review aimed to synthesize and report evidence on the effectiveness of interventions using social robots or computer agents to reduce loneliness in older adults and to explore intervention strategies.MethodsThe review adhered to the Arksey and O’Malley process for conducting scoping reviews. The SCOPUS, PUBMED, Web of Science, EMBASE, CINAHL, PsycINFO, ACM Digital Library and IEEE Xplore databases were searched in November, 2020. A two-step selection process identified eligible research. Information was extracted from papers and entered into an Excel coding sheet and summarised. Quality assessments were conducted using the Mixed Methods Appraisal Tool.ResultsTwenty-nine studies were included, of which most were of moderate to high quality. Eighteen were observational and 11 were experimental. Twenty-four used robots, four used computer agents and one study used both. The majority of results showed that robots or computer agents positively impacted at least one loneliness outcome measure. Some unintended negative consequences on social outcomes were reported, such as sadness when the robot was removed. Overall, the interventions helped to combat loneliness by acting as a direct companion (69%), a catalyst for social interaction (41%), facilitating remote communication with others (10%) and reminding users of upcoming social engagements (3%).ConclusionEvidence to date suggests that robots can help combat loneliness in older adults, but there is insufficient research on computer agents. Common strategies for reducing loneliness include direct companionship and enabling social interactions. Future research could investigate other strategies used in human interventions (eg, addressing maladaptive social cognition and improving social skills), and the effects of design features on efficacy. It is recommended that more robust experimental and mixed methods research be conducted, using a combination of validated self-report, observational, and interview measures of loneliness.

Effect of Design Features and Operating Conditions on the Performance of a Bipolar Membrane-Based Acid/Base Flow Battery

Effect of Design Features and Operating Conditions on the Performance of a Bipolar Membrane-Based Acid/Base Flow Battery

Assessing the Ergonomic Benefits of a New Adjustable Forklift Backrest

A new forklift backrest has been developed by incorporating adjustability concepts into the design to facilitate comfort to a wide range of users. We have conducted a comparative study between the new and original backrests to assess the effectiveness of design features. Using the phenomenon of restlessness, discomfort of the user was associated with the amount of body movement, where we have used a motion- capture system and a force platform to quantify the individuals’ movement for a wide range of body sizes. Meanwhile, subjective comfort and design feedback were collected using a questionnaire. Our results showed a reduction in the mean torso movement and the maximum center of pressure change of location by 300 and 6 mm, respectively, for the new design. Taking advantage of adjustability feature, the new backrest design exhibited enhanced comfort for longer durations and reduced magnitude of discomfort for a wide range of participants’ body sizes.

Lessening the Load of Misconceptions: Design-Based Principles for Algebra Learning

The current study examined the effectiveness of self-explanation prompts, visual signaling cues, and a combination of the two features on middle school students’ (N = 202) algebra learning. Also explored were the differential effects of features for students with faulty conceptual knowledge (evidenced by a higher prevalence of making errors during problem solving) on learning. That is, we assessed whether students who make prevalent conceptual errors predictive of algebra performance differentially benefit from design features. Participants were randomly assigned to complete 1 of 4 sets of worked example assignments supplemented with self-explanation prompts (n = 51), visual signaling cues (n = 49), both features (n = 51), or neither feature (n = 51). Worked examples supplemented with either self-explanation prompts or signaling cues led to greater learning from pre- to posttest in comparison to the worked example control, with practically meaningful effects. The effect of assignments supplemented with signaling cues was moderated by error prevalence. Those who made errors more frequently demonstrating misunderstanding of algebraic concepts (e.g., the meaning of a coefficient) benefited significantly more from visual signaling cues alone than self-explanation prompts alone or control assignments. These findings highlight the importance of considering differential effects of design features when used in combination or in isolation, particularly for struggling students.

Focused apodized forked grating coupler

The forked grating coupler (FGC) is an optical vortex interface for silicon photonics. Using the structure of a Bragg grating coupler with a calculated forked hologram, the FGC couples optical vortex modes into confined waveguide modes of a photonic integrated circuit. Design methodologies are given, as well as measured performance data from fabricated devices. Data are analyzed with a variety of metrics. The effectiveness of design features are evaluated. Advanced FGC designs are demonstrated with focused forked gratings, allowing feed length to be reduced, and with apodization improving vortex mode fidelity. Some configurations achieve over 25 dB multiplexing crosstalk isolation.

Variable pay and job performance of shop-floor workers in lean production

Purpose– The purpose of this paper is to investigate design features of variable pay plans adopted for shop-floor workers engaged in manufacturing firms that had implemented lean production systems, and the effects of design features on their job performance.Design/methodology/approach– In total, 892 shop-floor workers attached to lean implemented manufacturing firms in Sri Lanka responded for the study. Structural equation modelling was used for the data analysis.Findings– It was found that the performance evaluation-base for variable payments, variable pay calculation-base and goal setting for variable pay significantly predict job performance of the shop-floor workers.Originality/value– It could be expected that the academics and practitioners alike are motivated by their desire to clearly apprehend the contribution of variable pay plans on job performance of the shop-floor workers engaged in lean production systems. This demands more investigations to better understand the design features of variable pay plans.

The effect of design features of a transformer with a rotating magnetic field on the quality of the output voltage of a self-excited inverter

Self-excited inverters based on a transformer with a rotating magnetic field are considered. These semiconductor converters are characterized by a high quality of the supply and output current, as well as voltage, due to the use of a transformer with complete geometric, electric, and magnetic symmetry. It has been found that the quality of the output voltage of the self-excited inverter depends not only on the operation algorithms of the semiconductor commutator, but also on design solutions implemented in the transformer at the stage of designing the core, as well as the three-phase and circular windings. Two different design versions of the transformer with a rotating magnetic field are described. The magnetic-field curve typical of transformers with different-type cores, which is the complete characteristic for analyzing the quality of the electric energy of the self-excited inverter at the stage of design, is calculated. The relationship of the quality of the output voltage of the self-excited inverter with the magnetic-field curve and with different versions of the winding design is studied. To improve the quality of the electric energy of the self-excited inverter, the use of a split core and the skew of the magnetic axes of the three-phase and circular windings is proposed. It has been shown that the use of the transformer with the spit core and the skew of the magnetic axes of the windings makes it possible to reduce the total harmonic distortion of the phase voltages by seven- to tenfold times, which provides better electromagnetic compatibility of the self-excited inverter with the supply main and the load.

Effect of Design Features on Dynamic Characteristics of VCC Piston for I. C. Engine

Effect of Design Features on Dynamic Characteristics of VCC Piston for I. C. Engine

Characterization of a CH planar laser-induced fluorescence imaging system using a kHz-rate multimode-pumped optical parametric oscillator

The performance characteristics of a new CH planar laser-induced fluorescence (PLIF) imaging system composed of a kHz-rate multimode-pumped optical parametric oscillator (OPO) and high-speed intensified CMOS camera are investigated in laminar and turbulent CH4-H2-air flames. A multi-channel Nd:YAG cluster that produces up to 225 mJ at 355 nm with multiple-pulse spacing of 100 μs (corresponding to 10 kHz) is used to pump an OPO to produce up to 6 mJ at 431 nm for direct excitation of the A-X (0, 0) band of the CH radical. Single-shot signal-to-noise ratios of 82:1 and 7.5:1 are recorded in laminar premixed flames relative to noise in the background and within the flame layer, respectively. The spatial resolution and image quality are sufficient to accurately measure the CH layer thickness of ~0.4 mm while imaging the detailed evolution of turbulent flame structures over a 20 mm span. Background interferences due to polycyclic-aromatic hydrocarbons and Rayleigh scattering are minimized and, along with signal linearity, allow semi-quantitative analysis of CH signals on a shot-to-shot basis. The effects of design features, such as cavity finesse and passive injection seeding, on conversion efficiency, stability, and linewidth of the OPO output are also discussed.

Influence of prosthetic design on radiocapitellar concavity-compression stability

Radial head prostheses are available with multiple geometric properties. The effect of design features on radiocapitellar stability has not been investigated. The shape (depth and radius of curvature) of the articulating dish of a radial head prosthesis affects radiocapitellar stability. Radiocapitellar stability due to concavity-compression was evaluated in 8 fresh frozen elbows before and after radial head replacement with 2 different designs of radial head implants (RH 1 and RH 2). Both functioned as monopolar implants. Peak forces resisting subluxation and force-displacement characteristics were compared between the 2 and to the native radial head. Radial head design significantly affected radiocapitellar stability. RH 1, which had a deeper dish than RH 2, required significantly higher peak forces to subluxate the radiocapitellar joint. The peak subluxation forces and the slopes of the force-displacement curves were not significantly different from the native radial head for RH 1, but they were for RH 2. The shape of the articular dish (depth, radius of curvature) of a monopolar radial head implant affects its contribution to radiocapitellar stability. An implant that mimics normal anatomy is more effective than a shallow radial head implant with a radius of curvature that is longer than normal.

Effects of design features on combustion efficiency and emission performance of a biomass-fuelled fluidized-bed combustor

This paper presents an analysis of some measures leading to intensification of the combustion process in a biomass-fuelled fluidized-bed combustor with a cone-shape bed (or ‘conical FBC’). Two combustors firing rice husks with elevated fuel-ash content were the focus of this study. Compared to the pilot 350-kWth conical FBC exhibiting combustion efficiency of up to 96%, the newly constructed 400-kWth combustor included geometrical and design modifications aimed at improving the combustion efficiency and emission performance of the reactor. Differences between the air distributors and Δp–u diagrams (accounting for the total pressure drop across the air distributor and gas–solid fluidized bed) for the two reactors are discussed. Axial temperature and gas concentration (O2, CO and NOx) profiles in the combustors were compared for similar operating conditions (excess air and heat release rate per unit cross-sectional area). At excess air of 40–60%, the bed temperature in the advanced conical FBC was substantially, by about 180 °C, higher than that in the pilot combustor, mainly, due to better fuel–air mixing and higher residence time of reactants. The formation and decomposition of CO and NO in the bed region as well as in the freeboard of these two combustors showed quite different trends under similar operating conditions. At excess air of 40–60%, the CO emission from the advanced conical FBC was found to be much (7–8 times) lower than that from the pilot combustor, while the NOx emissions were represented by almost the same values. High (over 99%) combustion efficiency was achieved when firing rice husk in the advanced 400 kWth conical FBC for the range of excess air.

Analysis of Deformation and Stress Distribution of the Poly-Axial Pedicle Screw

The effect of design features of an internal spinal fixator under loading is critical to understanding of interaction between fixator and instrumented spine. In this study, we performed finite element analysis for spinal pedicle screw installed in the lumbar spine. The purpose of this study is to model and simulate the newly designed spinal pedicle screw. The deformation and stress of the screw are analyzed for the tightening process and loading process simulating the condition when it is installed in the human body as described in the ASTM F1717 procedure. We expected this study is to derive reliable results for developing a new model by analysis of design variables and fatigue behavior.

A field trial to evaluate the pollution potential to ground and surface waters from woodchip corrals for overwintering livestock outdoors

AbstractOutwintering beef cattle on woodchip corrals offers stock management, economic and welfare benefits when compared with overwintering in open fields or indoors. A trial was set up on a loamy sand over sand soil to evaluate the pollution risks from corrals and the effect of design features (size and depth of woodchips, stocking density, and feeding on or off the corral). Plastic‐lined drainage trenches at 9–10 m spacing under the woodchips allowed sampling of the leachate. Sampling of the soil to 3.6 m below the corral allowed evaluation of pollutant mitigation during vadose zone transport. Mean corral leachate pollutant concentrations were 443–1056 mg NH4‐N L−1, 372–1078 mg dissolved organic carbon (DOC) L−1, 3–13 mg NO3‐N L−1, 8 × 104–1.0 × 106Escherichia coli 100 mL−1 and 2.8 × 102–1.4 × 103 faecal enterococci 100 mL−1. Little influence of design features could be observed. DOC, NH4 and (in most cases) E. coli and faecal enterococci concentrations decreased 102–103 fold when compared with corral leachate during transport to 3.6 m but there were some cores where faecal enterococci concentrations remained high throughout the profile. Travel times of pollutants (39–113 days) were estimated assuming vertical percolation, piston displacement at field moisture content and no adsorption. This allowed decay/die‐off kinetics in the soil to be estimated (0.009–0.044 day−1 for DOC, 0.014–0.045 day−1 for E. coli and 0–0.022 day−1 for faecal enterococci). The mean [NO3‐N] in pore water from the soil cores (n = 3 per corral) ranged from 114 ± 52 to 404 ± 54 mg NO3‐N L−1, when compared with 59 ± 15 mg NO3‐N L−1 from a field overwintering area and 47 ± 40 mg NO3‐N L−1 under a permanent feeding area. However, modelling suggested that denitrification losses in the soil profile increased with stocking density so nitrate leaching losses per animal may be smaller under corrals than for other overwintering methods. Nitrous oxide, carbon dioxide and methane fluxes (measured on one occasion from one corral) were 5–110 g N ha−1 day−1, 3–23 kg C ha−1 day−1, and 5–340 g C ha−1 day−1 respectively. Ammonia content of air extracted from above the woodchips was 0.7–3.5 mg NH4‐N m−3.

Developing a Primary Science Methods Classroom

The purpose of this paper is to describe how and why a primary science methods classroom was conceived, designed, and developed for preservice and inservice teachers. Just as science educators believe that students learn best by constructing their knowledge of the natural world with the aid of a teacher and colleagues, science educators also believe that preservice and inservice teachers should learn in a collaborative and constructivist environment. Multiple dimensions relating to the dynamic processes of learning to teach, a ‘technical factor’ related to the physical and resource constraints that exist within a school, and sociocultural theory were used for the theoretical framework. A survey was given to 97 students who took a course in the classroom, six instructors were given a questionnaire, and three of these instructors were interviewed. These data sources sought to determine the effect of design features on student learning and instructor teaching. The results of the evaluation suggest students who used the classroom found their learning positively affected by the room design and instructors who taught in the classroom benefited by being able to teach in an inquiry and constructivist manner.

Effect of design features of welded joints on weld formation in electron beam welding dissimilar steels and alloys

Effect of design features of welded joints on weld formation in electron beam welding dissimilar steels and alloys

Effect of design features of welded joints on weld formation in electron beam welding dissimilar steels and alloys

Effect of design features of welded joints on weld formation in electron beam welding dissimilar steels and alloys

Designing information-supported performance

This paper discusses the progress we have made in document design and suggests some of the issues remaining to be addressed, particularly in relation to multimedia documents. In order to sharpen these issues, it reports three empirical studies of the varying effects that graphics in electronic documents have on readers and the reading process in different contexts. It concludes by discussing how to represent our growing knowledge about the effects of design features, and suggests that such an information resource is more usefully thought of as a "map" to be consulted than a recipe to be followed. The varied factors that must be taken into account when reaching design decisions may mean that the "map" will need to be an interactive document in order to be a useful tool for designers scaling the heights in the online century ahead.

Is the Cone Calorimeter Useful in Assessing Furniture Composite Behavior by the California Technical Bulletin 133 Test?

The California Technical Bulletin 133 (TB 133) test method is being used to regulate the fire performance of seating furniture in public buildings in some states. Such regulations in the marketplace have brought together a coalition of textile, fabric and furniture manufacturers to concentrate their efforts on trying to better understand combi nations of foam, fabric, barrier and styling features from the standpoint of fire perfor mance. Chemical suppliers to the polyurethane flexible foam industry are working towards de veloping correlations between bench scale test methods and the full scale California TB 133. A collection of eight upholstery fabrics, five interliner barrier fabrics and a fire retar dant foam were selected by the coalition as materials representative of contract furniture markets today. Foam/fabric composites which had been tested using the TB 133 procedure were tested in our laboratory using the Cone Calorimeter by the ASTM E 1354 test method. Results indicated that composite performance was dependent on the type of fabric and barrier used. The overall performance of the fabrics and barriers could be ranked similarly by both the California TB 133 and by the ASTM E 1354 test methods. Even though differences in combustion characteristics were noted between the two test methods, we were able to use criteria based on heat release values and correlate up to 75 % of the passes and failures obtained by TB 133 test criteria. The test worked better for composites that performed either very well or very poorly by TB 133. Test results reported in this paper are used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled labora tory conditions and must not be used to describe, appraise or predict the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. Test results may be used only as part of an overall fire risk assessment that takes into ac count all of the factors pertinent to the fire hazard of a particular material in a specific end use. Correlations between bench scale tests and full scale tests may help in narrowing the field of potential material candidates. However, bench scale tests cannot assess the effect of design features. Therefore, full scale testing remains necessary before final acceptance of any furniture .