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Accurate location information is crucial for ensuring the reliability of service robots, such as field vehicles and agricultural robots. These practical robots often encounter fluctuating or inclined terrains in dynamic conditions during operation. Additionally, the performance of mobile robots depends on the physical size and weight of the localization system–physically heavy systems may degrade performance. In this paper, we present a compact, lightweight RTK‐GNSS device weighing under 40 g, which achieves centimeter‐level accuracy across different attitudes and dynamic situations. To enhance signal reception and positioning performance, we lessen noise levels in the power circuit and radio‐frequency signal conditioning using a low‐dropout regulator and low‐noise amplifier. Utilizing the configured device, we verified centimeter‐level accuracy through experiments of tracking an unmanned ground vehicle. The potential of the device is substantiated via three application scenarios—a localization of a moving human for a wearable device, a heading estimation of a mobile robot in stationary conditions, and practical field tests in various signal‐reception environments. Attributable to its compact dimensions and lightweight features, the proposed device can yield a low system strain while maintaining high accuracy and reliable performance, rendering it highly adaptable for various robotic applications. [ABSTRACT FROM AUTHOR]

Westinghouse is developing a lead-cooled fast reactor (LFR) as its next-generation utility-scale nuclear power plant. To support its development, Westinghouse and its partners are building 10 test facilities to demonstrate key LFR phenomena, materials, and components in liquid lead. These test infrastructures are distributed across several institutions, and this paper focuses on those located within Westinghouse. It describes three state-of-the-art test rigs being installed in the Westinghouse facility in Springfields, United Kingdom, to test materials in liquid lead and to investigate key LFR phenomena, which will also be used to validate modeling and simulation tools. These facilities address material corrosion/erosion testing (MELECOR), lead freezing and under-lead viewing testing (LEFREEZ), and primary heat exchanger failure testing (LEWIN). This paper also describes the first liquid-lead test system to become operational at Westinghouse at the company's site in Churchill, Pennsylvania, i.e., a test rig named HELMET to conduct tensile tests in a molten-lead environment to investigate the potential susceptibility of LFR candidate materials to liquid-metal embrittlement. [ABSTRACT FROM AUTHOR]

This paper presents an assessment aimed at evaluating primary heat exchanger (PHE) failure of the Westinghouse Electric Company Lead-cooled Fast Reactor (LFR) and at designing a facility for testing phenomena involved in such failure. The system thermal-hydraulic code RELAP5/MOD3.3 was used to develop a transient analysis simulation at reactor scale. Because of RELAP5/MOD3.3's inability to mix working fluids, the steam injection effect was evaluated using the SIMMER-III code. The limits and strengths of both codes are highlighted throughout the paper. The reactor-scale steady-state results are in good agreement with the nominal operating condition. The transient results show that lead pool surface level variation and primary system pressurization during the PHE failure event are limited. The PHE failure testing facility was characterized, and a preliminary layout was developed. A separate-effects transient inside the vessel was analyzed with SIMMER-III and RELAP5/MOD3.3 runs. The simulation outcomes have provided useful data to inform subsequent design stages for the test facility. Different configurations of the facility have been assessed, highlighting the strengths and weaknesses of each design. The most important issue was identified to be lead pool swelling, reaching the vessel's lid and blocking the pressure relief vent. This poses a safety hazard that must be addressed and has been raised for resolution in subsequent design stages. The so-called V4 configuration is suggested as a starting point for further improvement of the facility. Furthermore, a smaller failure opening and lower lead level in the vessel are suggested. [ABSTRACT FROM AUTHOR]

What is the impact of housing adequacy on recent home modification, controlling for demographics and housing characteristics? This study examined home modifications of households with a member aged 65 or older, focusing on relationships between selected demographic and housing variables and home modification. Binary logistic regression analysis was used on a sample of 6,627 homeowners from the newly released 2019 American Housing Survey (AHS) dataset. This analysis of the 2019 AHS data is important because of its pre-COVID pandemic era perspective in terms of home modifications and older adults aging in place. Results showed that recent housing modifications were significantly affected by select demographic and housing factors. [ABSTRACT FROM AUTHOR]