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Background Study: Technology‐supported learning environments, act as significant observational and enabling indicators for evaluating and encouraging the digital revolution of education, are of vital importance in current educational research. Keeping track of the dynamics of technology‐supported learning environment research allows for the enrichment of theoretical studies and a prompt innovation of talent‐training environments. Objectives: The present study carried out a bibliometric analysis of the core collection of WoS database over the last two decades. Method: This study is a bibliometric research. We applied CiteSpace and VOSviewer for co‐occurrence and evolution analysis. In addition, we extracted the fundamental ideas and thoughts through reading and analysis. Results: First, the study found that technology‐supported learning environment research is in a growth phase, with core journals such as Interactive Learning Environments or Computers & Education. The findings show that a core research team comprised of such scholars as Hwang Gwo‐Jen, Lester James C. and Wong Lung‐Hsiang. Key nations of publishing and research strength are from China, the United States, the United Kingdom and the Netherlands. Second, the hot topics in research on technology‐supported learning environments were virtual learning environments, technology‐enabled learning environments and interactive learning environments. Nine study specifics were derived from these three topics such as moulding function, generating scenario, stimulating sensation, effect verification, design idea, research reflection, inquiry and research, virtual community, and mixed environment. Lastly, the frontier evolution offers a pattern of development from enhancing performance to changing mode to incorporating experience. Conclusion: Looking ahead, our research recommendations for the field of technology‐supported learning environments include a multifaceted approach. We should aim to enhance research designs and methodologies, develop contemporary guiding theories and strive for a balanced representation across various educational domains, expanding our scope to encompass all academic disciplines. In terms of practical application, it is imperative to focus on the design and implementation of technology‐supported learning environments from three critical perspectives: "change‐demand," "student‐learning" and "online‐offline." These approaches will collectively ensure that technology‐supported learning environments are both innovative and responsive to the diverse needs of the educational landscape. Lay Description: What is already known about this topic: Technology‐supported learning environments are currently a focal and hot research topic in the field of education.Although numerous studies have been conducted on the learning environment of technical support, there has yet to be a systematic and comprehensive review of the related research. What this paper adds: This study provides a comprehensive review of research on the technology‐supported learning environments over the past two decades.This study primarily presents an overview of research on the technology‐supported learning environments over the past two decades, focusing on main literature, research strength, hot topics and frontier evolution. Implications for practice and/or policy: Researchers need to further advance research on technology‐supported learning environments by enriching research designs and methods, constructing up‐to‐date guiding theories and achieving a balance across different educational domains while extending the reach to all disciplines.Educational practitioners need to pay attention to the design and implementation of technology‐supported learning environments from the three viewpoints of "change‐demand," "student‐learning" and "online‐offline." [ABSTRACT FROM AUTHOR]

This case study demonstrates the application of an unsupervised topic modeling algorithm to 7,773 English-language articles published in the Library Quarterly from 1931 to 2015. The analysis of 85 years of the journal's output follows an exploratory data analysis framework to generate novel hypotheses about the history of LIS using topic modeling, a method for identifying clusters of co-occurring words within large collections of text. The paper closely examines two topics that suggest differences in gender representation in the journal to propose and support a new hypothesis regarding the historical inclusion of gendered objects of study in LIS literature. [ABSTRACT FROM AUTHOR]

Highlights • 3D models can be used to accurately predict flood wave propagation in natural environments. • 3D non-hydrostatic models can be used to study cases when flow becomes locally pressurized. • 3D models can be used to estimate effectiveness of flood protection measures. Abstract This paper discusses development and validation of a 3-D, non-hydrostatic, Reynolds-Averaged Navier–Stokes (RANS) model using the Volume of Fluid (VOF) approach to simulate flooding events in natural environments. A series of validation simulations in simple and complex geometries are performed to test the different modules of the flow solver. The paper also discusses the differences between simulation results obtained using the 3-D model and those obtained using a standard, 2-D hydrostatic, depth-averaged model. The predictions by the two models show fairly large differences in regions where 3-D effects are expected to be significant (e.g., in regions containing highly-curved river reaches and near hydraulic structures). Then, the validated 3-D model is employed to investigate the efficiency of using flood-protection walls to reduce adverse effects of flooding in the Iowa River near Iowa City, Iowa, USA. Finally, the propagation of a flood wave in a reach of the Iowa River containing a bridge is simulated and the effects of the flow becoming pressurized beneath the bridge deck are discussed. For such applications, in which the regime can change locally between open channel and pressurized flow, the use of fully 3-D, non-hydrostatic models may be the only viable option to accurately predict flow hydrodynamics and its effects on bed shear stresses and sediment entrainment potential, especially around locations where the flow becomes pressurized. [ABSTRACT FROM AUTHOR]

• We evaluate the empirical relevance of the profit-squeeze mechanism to HP and Hamilton filters using quarterly data for the United States from 1948-67 to 2016. • We extend Goodwin's (1967) growth-cycle model to include the employment rate, income distribution, and capacity utilisation as endogenous variables. • We show analytically that the system always admits a family of periodic solutions. • The model is estimated econometrically using the Autoregressive Distributed Lag (ARDL) approach. • Through numerical simulations and making use of our estimations, we confirm that fluctuations are persistent and bounded. Vector Autoregressive (VAR) models have been applied for a long time now to study profit-squeeze cycles, most of the time using problematic Hodrick-Prescott (HP) filtered time series. In a recent paper, Hamilton (2018) has provided a simple alternative that overcomes the main drawbacks of the HP procedure. In order to evaluate the empirical relevance of the profit-squeeze mechanism, we compare both methodologies using quarterly data for the United States after the Second World War. It is shown that using the Hamilton detrending method significantly increases the magnitude as well as the time length of the response. Furthermore, we present an extension of Goodwin's (1967) growth-cycle model that includes employment rates, income distribution, and capacity utilisation as endogenous variables. We demonstrate analytically that the system always admits a family of periodic solutions. The model is estimated using the Autoregressive Distributed Lag (ARDL) approach. Through numerical simulations and making use of our estimations, we confirm that fluctuations are persistent and bounded. [ABSTRACT FROM AUTHOR]

This paper develops a frequentist model averaging approach for threshold model specifications. The resulting estimator is proved to be asymptotically optimal in the sense of achieving the lowest possible squared errors. In particular, when combining estimators from threshold autoregressive models, this approach is also proved to be asymptotically optimal. Simulation results show that for the situation where the existing model averaging approach is not applicable, our proposed model averaging approach has a good performance; for the other situations, our proposed model averaging approach performs marginally better than other commonly used model selection and model averaging methods. An empirical application of our approach on the US unemployment data is given. [ABSTRACT FROM AUTHOR]

Abstract For future engines to become more efficient, with enhanced fuel economy and increased power output, accurate prediction of new designs is required over the full lifetime of an engine. The analysis uses of a local pressure coefficient of boundary shear strength of asperities value, taking into account the localised effects of surface texture, coating and surface deposition. XPS spectra analysis was also carried out to identify the surface depositions as a result of combustion, not previously taken into account during piston ring pack simulation. It was found that piston varnish on the liner corresponded to higher values of the pressure coefficient of boundary shear strength of asperities, showing the importance of using real system components run under representative operating conditions. Highlights • The paper presents measurements of ς from a used real cylinder liner surface. • XPS is used to identify chemical composition of liner surface regions. • Depositions and tribo-films on the liner surface are characterised. • Results show that boundary friction is dependent on the by-products of combustion over time. • Simulation shows that results for friction can vary by 30% at peak combustion pressure. [ABSTRACT FROM AUTHOR]

This paper describes environmental systems games developed for energy and water resource use designed to be adaptable from high school to undergraduate use. Two of the games are computer simulations with adjustable levels of difficulty that can be done in a computer lab or as a homework assignment. The third is a peer-to-peer roleplayer game designed for an immersive in-class simulation. For the energy and the peer-to-peer water games, we describe (1) the overall strategy or story line adopted, (2) the manner in which the game is played by students in a classroom setting, (3) the use of scientific literature in conceptualizing and parameterizing the game, and (4) possible game extensions. Preliminary data from use at the undergraduate level shows that the games are very well-received by students and, consistent with other research on quasi-experimental simulations, likely enhance learning outcomes. [ABSTRACT FROM AUTHOR]

To address the inadequacy of ambulance design standards, the Department of Homeland Security Science and Technology Directorate, the National Institute of Standards and Technology, the National Institute for Occupational Safety and Health, and BMT Designers and Planners have collaborated to develop new design standards for ambulance patient compartments. This paper presents a simulation-based approach to evaluate and guide improving patient compartment designs that conform to developed requirements for better performance and safety of ambulance users. Those requirements address hazards stemming from (1) the inability of providers to remain safely restrained while treating patients, and (2) the musculoskeletal damage from awkward body postures. An initial design was developed through the axiomatic design approach with inputs from stakeholders such as emergency medical service providers and ambulance manufacturers. The design was imported into a human task simulation tool. It was tested for performance to identify areas for further improvements, which resulted in a second design concept. This paper shows how computer simulation was used to evaluate the effectiveness of the two successive design concepts in enabling providers to perform a range of medical care tasks while remaining seated and restrained. We also evaluated the musculoskeletal effect of these designs on the providers. The results showed that using a simulation-based evaluation produced patient compartments that better meet user requirements when compared with traditional designs. This research produced a set of requirements and recommendations that we believe will lead to better design standards and guidelines for the next generation of ambulances. [ABSTRACT FROM AUTHOR]

The American automobile industry is facing substantial environmental and energy challenges driving the pursuit of alternative powertrain technologies—“The intervening mechanism by which power is transmitted from an engine to a propeller or axle that it drives,” which nominally includes engine, transmission, drive shafts, differentials, and the final drive. Emerging alternative fuel vehicles are showing their potential to address these challenges. However, diffusion of new technologies has many complications. This paper uses system dynamics modeling to investigate the impacts of individual and organizational parameters. This model embeds two traditional modeling methods for technology adoption, the Bass diffusion model and multinomial logit regression method. Five types of powertrain systems and three major stakeholders are considered. Mathematical relationships among different variables are elaborated. The qualitative impacts of government feebate, manufacturer willingness, and consumer purchasing preferences on economic and environmental issues are addressed using scenario analysis. [ABSTRACT FROM AUTHOR]

Drug-drug interactions (DDIs) are a common cause of adverse drug events (ADEs). The electronic medical record (EMR) database and the FDA's adverse event reporting system (FAERS) database are the major data sources for mining and testing the ADE associated DDI signals. Most DDI data mining methods focus on pair-wise drug interactions, and methods to detect high-dimensional DDIs in medical databases are lacking. In this paper, we propose 2 novel mixture drug-count response models for detecting high-dimensional drug combinations that induce myopathy. The "count" indicates the number of drugs in a combination. One model is called fixed probability mixture drug-count response model with a maximum risk threshold (FMDRM-MRT). The other model is called count-dependent probability mixture drug-count response model with a maximum risk threshold (CMDRM-MRT), in which the mixture probability is count dependent. Compared with the previous mixture drug-count response model (MDRM) developed by our group, these 2 new models show a better likelihood in detecting high-dimensional drug combinatory effects on myopathy. CMDRM-MRT identified and validated (54; 374; 637; 442; 131) 2-way to 6-way drug interactions, respectively, which induce myopathy in both EMR and FAERS databases. We further demonstrate FAERS data capture much higher maximum myopathy risk than EMR data do. The consistency of 2 mixture models' parameters and local false discovery rate estimates are evaluated through statistical simulation studies. [ABSTRACT FROM AUTHOR]

A primary purpose of health insurance is to protect families from medical expenditure risk. Despite this goal and despite the fact that research has found that Medicaid can crowd out private coverage, little is known about the effect of Medicaid on families' spending patterns. This paper implements a simulated instrumental variables strategy with data from the Consumer Expenditure Survey to estimate the effect of an additional family member becoming eligible for Medicaid on family-level health insurance coverage and spending. The results indicate that an additional family member becoming eligible for Medicaid increases the number of people in the family with Medicaid coverage by about 0.135-0.142 and decreases the likelihood that a family has any medical spending in a quarter by 2.7 percentage points. As previous research often finds with different data sets, I find evidence that Medicaid expansions crowd out some private coverage. Unlike most other data sets, the Consumer Expenditure Survey allows for considering the financial implications of crowd-out. The results indicate that families that transition from private coverage to Medicaid are able to spend significantly less on health insurance expenses, meaning Medicaid expansions can be welfare improving for families even when crowd-out occurs. [ABSTRACT FROM AUTHOR]

Storm-scale and mesocyclone-scale processes occurring contemporaneously with a tornado in the Goshen County, Wyoming, supercell observed on 5 June 2009 during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) are examined using ensemble analyses produced by assimilating mobile radar and in situ observations into a high-resolution convection-resolving model. This paper focuses on understanding the evolution of the vertical structure of the storm, the outflow buoyancy, and processes affecting the vertical vorticity and circulation within the mesocyclone that correspond to changes in observed tornado intensity. Tornadogenesis occurs when the low-level mesocyclone is least negatively buoyant relative to the environment, possesses its largest circulation, and is collocated with the largest azimuthally averaged convergence during the analysis period. The average buoyancy, circulation, and convergence within the near-surface mesocyclone (on spatial scales resolved by the model) all decrease as the tornado intensifies and matures. The tornado and its parent low-level mesocyclone both dissipate surrounded by a weakening rear-flank downdraft. The decreasing buoyancy of parcels within the low-level mesocyclone may partly be responsible for the weakening of the updraft surrounding the tornado and decoupling of the mid- and low-level circulation. Although the supply of horizontal vorticity generated in the forward flank of the storm increases throughout the life cycle of the tornado, it is presumably less easily tilted and stretched on the mesocyclone-scale during tornado maturity owing to the disruption of the low-level updraft/downdraft structure. Changes in radar-measured tornado intensity lag those of ensemble Kalman filter (EnKF) mesocyclone vorticity and circulation. [ABSTRACT FROM AUTHOR]

Virtual Reality (VR) can reduce time and costs, and lead to increases in quality, in the development of a product. Given the pressure on car companies to reduce time-to-market and to continually improve quality, the automotive industry has championed the use of VR across a number of applications, including design, manufacturing, and training. This paper describes interviews with 11 engineers and employees of allied disciplines from an automotive manufacturer about their current physical and virtual properties and processes. The results guided a review of research findings and scientific advances from the academic literature, which formed the basis of recommendations for future developments of VR technologies and applications. These include: develop a greater range of virtual contexts; use multi-sensory simulation; address perceived differences between virtual and real cars; improve motion capture capabilities; implement networked 3D technology; and use VR for market research. [ABSTRACT FROM AUTHOR]

A web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savings to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties. [ABSTRACT FROM AUTHOR]

Coalbed methane is a worthwhile potential energy source, because methane gas is eco-friendly and a huge amount of coalbed methane has been buried in the United States, China, Australia, etc. This paper introduces a new simulation model of a vacuum pressure swing adsorption process that has been widely used to purify unconventional gases such as coalbed methane and landfill gas. The developed mathematical model includes a novel interstitial gas velocity equation derived by using a mole balance concept and an overall mass balance equation. The model is verified by comparing with three sets of laboratory-scale (about 0.5 Nm³h-1) experimental data and one set of pilot-scale (100 Nm³h-1) design data. Because the differences between the simulation results and the data are reasonably small, one can conclude that the 200 times scale-up design through the new simulation model is successful. [ABSTRACT FROM AUTHOR]

With vapor compression systems consuming a significant portion of the overall U.S. energy consumption each year, extensive efforts have been made toward the development of control strategies which aim to maximize system efficiency while providing the desired cooling. However, previous control strategies under-utilize a degree of freedom corresponding to the amount of refrigerant in the system, which is related to condenser subcooling and can significantly affect system efficiency. In this paper, an alternative system architecture, which utilizes a receiver and an additional electronic expansion valve, is used to provide independent control of condenser subcooling. Simulation and experimental results show there exists an optimal subcooling which maximizes system efficiency; however, this optimal subcooling changes with operating conditions. Therefore, extremum seeking control is implemented to find the optimal subcooling in an adaptive, model-free manner. Experimental results demonstrate a 9% increase in efficiency using the alternative architecture and extremum seeking control. [ABSTRACT FROM AUTHOR]

The mission of the United States (U.S.) Department of Energy/National Energy Technology Laboratory (DOE/NETL) Carbon Capture Program is to develop the next generation of advanced CO 2 capture concepts for the power-generation sector. The Carbon Capture Program employs a down-selection process that graduates technologies from a large portfolio of laboratory/bench-scale projects to a smaller set of small-scale pilot projects and eventually to an even smaller group of large-scale pilot projects. At every scale, computer simulation plays a significant role in guiding experimental efforts and accelerating the overall pace of technology development. This down-selection process serves to de-risk industrial investment, given that there is insufficient information generated at the laboratory/bench scale to confidently predict eventual commercial success. The Carbon Capture Program is currently engaged in efforts to advance the next generation of capture technologies to large pilot scale. Three capture technologies have been awarded Phase I projects in a competition to build large-scale pilots for advanced energy and post combustion capture systems. In addition, six capture technologies are working toward large-scale pilot testing at Technology Center Mongstad in Norway. Advances along three innovation pathways—materials, processes, and equipment—have been critical in preparing these technologies for large pilot-scale testing. This paper describes the approach that is being followed by the Carbon Capture Program to advance the technologies and provides brief descriptions of the technical innovations that have prepared individual technologies for large pilot-scale testing. [ABSTRACT FROM AUTHOR]