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Force plate testing is becoming more commonplace in sport due to the advent of commercially available, portable, and affordable force plate systems (i.e., hardware and software). Following the validation of the Hawkin Dynamics Inc. (HD) proprietary software in recent literature, the aim of this study was to determine the concurrent validity of the HD wireless dual force plate hardware for assessing vertical jumps. During a single testing session, the HD force plates were placed directly atop two adjacent Advanced Mechanical Technology Inc. in-ground force plates (the “gold standard”) to simultaneously collect vertical ground reaction forces produced by 20 participants (27 ± 6 years, 85 ± 14 kg, 176.5 ± 9.23 cm) during the countermovement jump (CMJ) and drop jump (DJ) tests (1000 Hz). Agreement between force plate systems was determined via ordinary least products regression using bootstrapped 95% confidence intervals. No bias was present between the two force plate systems for any of the CMJ and DJ variables, except DJ peak braking force (proportional bias) and DJ peak braking power (fixed and proportional bias). The HD system may be considered a valid alternative to the industry gold standard for assessing vertical jumps because fixed or proportional bias was identified for none of the CMJ variables (n = 17) and only 2 out of 18 DJ variables.

The aim of the present study was to examine the value of FORCE dual-energy CT in grading the clear cell renal cell carcinoma (ccRCC). A total of 35 cases of ccRCC were included. Hematoxylin and eosin staining was performed, and the cases were divided into low- (Fuhrman I-II) and high-grade (Fuhrman III-IV) groups. FORCE dual-energy CT parameters, including virtual network computing CT value (VNCV), iodine overlay value (IOV), mixed energy CT value (MEV), iodine concentration (IC), normalized iodine concentration (NIC), NIC based on aorta (NICA), NIC based on cortex (NICC) and NIC based on medulla (NICM), were analyzed and compared. Receiver operating characteristic analysis was also performed. There were significant differences in the arterial phase IOV, MEV and IC, and the venous phase IOV and IC between the low- and high-grade groups. No significant differences were observed in VNCV and MEV between the low -and high-grade groups in the venous phase. Significant differences were observed in the NICA and NICC between these two groups, however no difference was observed in NICM. There were significant differences in the tumor CT values for the arterial phase at the 40, 60, 80 and 100 kiloelectron volt (keV) between the low- and high-grade groups, while no significant differences were observed at the 120-140 keV levels. The k-slope for the low-grade group was significantly higher than the high-grade group. In addition, the area under curve for the arterial phase IOV, arterial phase MEV, arterial phase IC, aortic NIC, cortical NIC, venous phase IOV, venous phase IC and curve slope K of mono-energy CT value suggested high value in diagnosis of low- and high-grade ccRCC cases.

The conventional frequency domain method (CFDM) and dual-force-based time domain method (DTDM) are often used to solve the steady-state response of system with complex damping under an arbitrary force. However, the calculation efficiency of the DTDM is low due to the straightforward summation operation of series even if the solution of the DTDM is the exact real part of the solution. In addition, since the CFDM only can obtain the real part of solution not the complete solution, it gives misleading information that the solution does not have an imaginary part. In this paper, a fast frequency domain method (FFDM) is proposed to calculate the complete response of complex damping system including the imaginary part with a higher accuracy in a much faster manner. The new FFDM uses half of the Fourier series of the discrete Fourier transform of the actual arbitrary force to construct the Fourier series of the dual force, followed by calculating the time history response using the inverse fast Fourier transform. The new developed method is validated through three numerical examples with harmonic and seismic excitations. The numerical results show that the accuracy of the new FFDM is compatible to the DTDM but with much higher computational efficiency.

On-line walking speed control in human-powered exoskeleton systems is a big challenge, the translations of human intention to increase or decrease walking speed in maneuverable human exoskeleton systems is still complex field. In this paper, we propose a novel sensing technique to control the walking speed of the system according to the pilot intentions and to minimize the interaction force. We introduce a new sensing technology “Dual Reaction Force (DRF)” sensors, and explain the methodology of using it in the investigation of walking speed changing intentions. The force signals mismatch successfully applied to control the walking speed of the exoskeleton system according to the pilot intentions. Typical issues on the implementation of the sensory system are experimentally validated on flat terrain walking trails. We developed an adaptive trajectory frequency control algorithm to control the walking speed of HUman-powered Augmentation Lower Exoskeleton (HUALEX) within the human wearer intended speed. Based on the mismatch of DRF sensors, we proposed a new control methodology for walking speed control. Human intention recognition and identification through an sensorized footboard and smart shoe is achieved successfully in this work, the new term heel contact time H C T is main feedback signal for the control algorithm. From the experimental walking trails we found that, the H C T during flat walking ranges from 0.69±0.05 sec and 0.41±0.07 sec while walking speed varies between 1 m / s and 2.5 m / s . The proposed algorithm used an Adaptive Central Pattern Generators (ACPGs) applied to control joint trajectory frequency, the different walking speeds associated with different functioning of human body CPGs frequency. We validated the proposed control algorithm by simulations on single Degree of Freedom (1-DoF) exoskeleton platform, the simulation results show the efficiency and validated that the proposed control algorithm will provides a good walking speed control for the HUALEX exoskeleton system.

In Unraveling the Gray Area Problem , Luke Griffith examines the US role in why the Intermediate-Range Nuclear Forces (INF) Treaty took almost a decade to negotiate and then failed in just thirty years. The INF Treaty enhanced Western security by prohibiting US and Russian ground-based missiles with maximum ranges of 500 to 5,500 kilometers. Significantly, it eliminated hundreds of Soviet SS-20 missiles, which could annihilate targets throughout Eurasia in minutes. Through close scrutiny of US theater nuclear policy from 1977 to 1987, Griffith describes the Carter administration's masterminding of the dual-track decision of December 1979, the North Atlantic Treaty Organization (NATO) initiative that led to the INF Treaty. The Reagan administration, in turn, overcame bureaucratic infighting, Soviet intransigence, and political obstacles at home and abroad to achieve a satisfactory outcome in the INF negotiations. Disagreements between the US and Russia undermined the INF Treaty and led to its dissolution in 2019. Meanwhile, the US is developing a new generation of ground-based, INF-type missiles that will have an operational value on the battlefield. Griffith urges policymakers to consider the utility of INF-type missiles in new arms control negotiations. Understanding the scope and consistency of US arms control policy across the Carter and Reagan administrations offers important lessons for policymakers in the twenty-first century.

This chapter presents the design, analysis, and testing of a robotic compliant gripper with integrated position and force sensors dedicated to automated microhandling tasks. The gripper delivers a large gripping range with a bidirectional drive. It is capable of detecting the gripping force and environmental interaction forces in horizonal and vertical axes. A variable‐stiffness compliant mechanism is designed to provide the force sensing with dual sensitivities and dual measuring ranges. Analytical models are derived to predict the gripping range, force sensing sensitivities and ranges, which are verified by conducting finite‐element analysis (FEA) simulations. A prototype gripper is developed for experimental studies. Results show that the single strain‐gauge force sensor is able to detect the gripping and interaction forces in an alternate manner. The dual‐sensitivity, dual‐range force sensor provides a solution to fine and coarse force sensing in smaller and larger ranges, respectively.

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\"This study suggests that multitasking constitutes an important source of gender inequality, which can help explain previous findings that mothers feel more burdened and stressed than do fathers even when they have relatively similar workloads. Using data from the 500 Family Study, including surveys and the Experience Sampling Method, the study examines activities parents simultaneously engage in and how they feel when multitasking. We find that mothers spend 10 more hours a week multitasking compared to fathers and that these additional hours are mainly related to time spent on housework and childcare. For mothers, multitasking activities at home and in public are associated with an increase in negative emotions, stress, psychological distress, and work-family conflict. By contrast, fathers' multitasking at home involves less housework and childcare and is not a negative experience. We also find several similarities by gender. Mothers' and fathers' multitasking in the company of a spouse or children are positive experiences, whereas multitasking at work, although associated with an increased sense of productivity, is perceived as a negative experience.\" (Author's abstract, IAB-Doku). Die Untersuchung enthält quantitative Daten. Forschungsmethode: empirisch; Befragung. Die Untersuchung bezieht sich auf den Zeitraum 1999 bis 2000.

Perovskite oxides have emerged as alternative anode materials for hydrocarbon‐fueled solid oxide fuel cells (SOFCs). Nevertheless, the sluggish kinetics for hydrocarbon conversion hinder their commercial applications. Herein, a novel dual‐exsolved self‐assembled anode for CH4‐fueled SOFCs is developed. The designed Ru@Ru‐Sr2Fe1.5Mo0.5O6‐δ(SFM)/Ru‐Gd0.1Ce0.9O2‐δ(GDC) anode exhibits a unique hierarchical structure of nano‐heterointerfaces exsolved on submicron skeletons. As a result, the Ru@Ru‐SFM/Ru‐GDC anode‐based single cell achieves high peak power densities of 1.03 and 0.63 W cm−2 at 800 °C under humidified H2 and CH4, surpassing most reported perovskite‐based anodes. Moreover, this anode demonstrates negligible degradation over 200 h in humidified CH4, indicating high resistance to carbon deposition. Density functional theory calculations reveal that the created metal‐oxide heterointerfaces of Ru@Ru‐SFM and Ru@Ru‐GDC have higher intrinsic activities for CH4 conversion compared to pristine SFM. These findings highlight a viable design of the dual‐exsolved self‐assembled anode for efficient and robust hydrocarbon‐fueled SOFCs. To achieve efficient and robust CH4 fueled solid oxide fuel cells, a hierarchical Ru@Ru‐Sr2Fe1.5Mo0.5O6‐δ (SFM)/Ru‐Gd0.1Ce0.9O2‐δ (GDC) anode is developed by an innovative integration of self‐assembly and dual exsolution. The single cell using this anode delivers a high peak power density of 0.63 W cm−2 at 800 °C and a remarkable stability for 200 h using humidified CH4 as fuel.