How Long Do Treatment Effects Last? Persistence and Durability of a Descriptive Norms Intervention's Effect on Energy Conservation

Behavioral decision research has profoundly changed our understanding of decision-making. Recent research has begun to explore how behavioral insights can influence behavior in the world, at scale. This work often involves field experiments studying outcomes over short time windows. We study a descriptive social norms intervention's impact on household energy usage continuously over 39 to 49 months. Our two field experiments (N=155,000 households) each have three conditions: untreated control, continued treatment, and treatment that is subsequently discontinued. We find that continued treatment reduces energy usage over the entire period (“durability”). Further, after treatment is discontinued, a sizable energy use reduction persists (“persistence”). Finally, continued treatment generates a greater impact over time than discontinued treatment, showing that continued treatment exerts incremental influence on behavior over and above persistence. We discuss implications, describe how long-term persistence can occur, and argue that future behavioral decision research should address long-term effects of interventions

A new algorithm for extended nonequilibrium molecular dynamics simulations of mixed flow

In this work, we develop a new algorithm for nonequilibrium molecular dynamics of fluids under planar mixed flow, a linear combination of planar elongational flow and planar Couette flow. To date, the only way of simulating mixed flow using nonequilibrium molecular dynamics techniques was to impose onto the simulation box irreversible transformations. This would bring the simulation to an end as soon as the minimum lattice space requirements were violated. In practical terms, this meant repeating the short simulations to improve statistics and extending the box dimensions to increase the total simulation time. Our method, similar to what has already been done for pure elongational flow, allows a cuboid box to deform in time following the streamlines of the mixed flow and, after a period of time determined by the elongational field, to be mapped back and recover its initial shape. No discontinuity in physical properties is present during the mapping and the simulation can, in this way, be extended indefinitely. We also show that the most general form of mixed flow, in which the angle between the expanding (or contracting) direction and the velocity gradient axis varies, can be cast in a so-called canonical form, in which the angle assumes values that are multiples of π (when a mixed flow exists), by an appropriate choice of the field parameters

Investigation into using resonant frequency measurements to predict the mechanical properties of Ti-6Al-4V manufactured by selective laser melting

There is a need to qualify additively manufactured parts that are used in highly regulated industries such as aerospace and nuclear power. This paper investigates the use of resonant ultrasound measurements to predict the mechanical properties of Ti-6Al-4V manufactured by selective laser melting using a Renishaw AM 250. It is first demonstrated why R2 should not be used to assess the predictive capability of a model, before introducing a method for calculating predicted R2, which is then used to assess the models. It is found that a linear model with the resonant frequency peaks as predictors cannot be used to predict elongation at failure or reduction in area. However, linear models did demonstrate better predictive capabilities for Young’s modulus, yield strength, and especially ultimate tensile strength

Simulation Evaluation of Controller-Managed Spacing Tools under Realistic Operational Conditions

Controller-Managed Spacing (CMS) tools have been developed to aid air traffic controllers in managing high volumes of arriving aircraft according to a schedule while enabling them to fly efficient descent profiles. The CMS tools are undergoing refinement in preparation for field demonstration as part of NASA's Air Traffic Management (ATM) Technology Demonstration-1 (ATD-1). System-level ATD-1 simulations have been conducted to quantify expected efficiency and capacity gains under realistic operational conditions. This paper presents simulation results with a focus on CMS-tool human factors. The results suggest experienced controllers new to the tools find them acceptable and can use them effectively in ATD-1 operations

Characterization of a Common-Source Amplifier Using Ferroelectric Transistors

This paper presents empirical data that was collected through experiments using a FeFET in the established common-source amplifier circuit. The unique behavior of the FeFET lends itself to interesting and useful operation in this widely used common-source amplifier. The paper examines the effect of using a ferroelectric transistor for the amplifier. It also examines the effects of varying load resistance, biasing, and input voltages on the output signal and gives several examples of the output of the amplifier for a given input. The difference between a commonsource amplifier using a ferroelectric transistor and that using a MOSFET is addressed

Characterization of a Common-Gate Amplifier Using Ferroelectric Transistors

In this paper, the empirical data collected through experiments performed using a FeFET in the common-gate amplifier circuit is presented. The FeFET common-gate amplifier was characterized by varying all parameters in the circuit, such as load resistance, biasing of the transistor, and input voltages. Due to the polarization of the ferroelectric layer, the particular behavior of the FeFET common-gate amplifier presents interesting results. Furthermore, the differences between a FeFET common-gate amplifier and a MOSFET common-gate amplifier are examined

A Mathematical Model of a Simple Amplifier Using a Ferroelectric Transistor

This paper presents a mathematical model characterizing the behavior of a simple amplifier using a FeFET. The model is based on empirical data and incorporates several variables that affect the output, including frequency, load resistance, and gate-to-source voltage. Since the amplifier is the basis of many circuit configurations, a mathematical model that describes the behavior of a FeFET-based amplifier will help in the integration of FeFETs into many other circuits

Rapid Manufacturing in Biomedical Materials: Using Subtractive Rapid Prototyping for Bone Replacement

This paper presents methods for the rapid manufacturing of replacement bone fragments using a Subtractive Rapid Prototyping process called CNC-RP. The geometry of segmental defects in bone, resulting from traumatic injury or cancerous tumor resection, can be reverse-engineered working from medical images (such as CT scans), and then accurate defect fillers can be automatically generated in advanced synthetic biomaterials and other bioactive/biocompatible materials. The research provides evidence that suitable bone geometries can be created using subtractive RP from a variety of materials including Trabecular Metal® (porous tantalum), polymers, ceramics, and actual bone allografts. The research has implications in the orthopaedic treatment of segmental bone defects, as custom prototyped bone fillers should aid in bone growth and improve recovery.Mechanical Engineerin

Moving on : the challenges for foreign language learning on transition from primary to secondary school

Europe's commitment to language learning has resulted in higher percentages of pupils studying foreign languages during primary education. In England, recent policy decisions to expand foreign language learning at primary level by 2010 create major implications for transition to secondary. This paper presents findings on transition issues from case studies of a DfES-funded project evaluating 19 local authority Pathfinders piloting the introduction of foreign language learning at primary level. Research on transition in other countries sets these findings in context. Finally, it investigates the challenges England faces for transition in the light of this expansion and discusses future implications

Technology Use in US Manufacturing

This paper examines the technology use of US manufacturing businesses. Results from a 2023 survey of US manufacturers (n=268) show that computer-aided design (CAD), numerically or computer-controlled machines, and programmable controllers / programmable logic controllers have considerably higher adoption rates than Industry 4.0 technologies such as virtual and augmented reality, robots, and AI / machine learning. The most frequently cited barriers to the use of Industry 4.0 technologies are the size and needs (e.g., “products don’t require technology”) of a company more so than concerns about various aspects of technology (e.g., fear of obsoletion). When selecting technologies to use, US manufacturers consider the impacts of the technology on production and the business (e.g., enhance product quality, increase worker productivity) and costs (reduce production costs, costs of purchasing the technology) more so than the skills of workers and recommendations of (or use by) other businesses, industry associations, colleges, or universities. Future research using the survey data will provide a more in-depth analysis of technology use and its broader impacts on businesses and the regions where they are located