Transition Speed Research Articles

Institutional reform, technology adoption and redistribution: a political economy perspective

We examine technology adoption and growth in a political economy framework where two alternative mechanisms of redistribution are on the menu of choice for the economy. One of these is a lump-sum transfer given to agents in the economy. The other is in the form of expenditure directed towards institutional reform aimed at bringing about a reduction in the cost of technology adoption in the presence of uncertainty. The choice over these mechanisms is examined under three alternative approaches to collective decision making, namely a voting mechanism, and social planning with a Benthamite and Rawlsian social welfare function respectively. We find that the extent of uncertainty, and initial inequality, working through the political economy mechanism, have a positive impact on long run average wealth levels in the economy in all settings. All economies converge to the same inequality and growth rates in the long run; however, the speed of transition is fastest with the voting mechanism and slowest in the case of social planning with the Rawlsian social welfare function. Transitional inequality is highest in the Rawlsian framework, suggesting that egalitarian objectives in collective decision making do not necessarily correspond to egalitarian outcomes for the economy.

First person – Harmen Koning

ABSTRACT First Person is a series of interviews with the first authors of a selection of papers published in Biology Open, helping early-career researchers promote themselves alongside their papers. Harmen Koning is first author on ‘ A deep-dive into fictive locomotion – a strategy to probe cellular activity during speed transitions in fictively swimming zebrafish larvae’, published in BiO. Harmen is a PhD student in the lab of Henrik Boije at the Department of Immunology, Genetics and Pathology, Uppsala University, Sweden, investigating the neuronal networks of locomotion in the zebrafish spinal cord to get a better understanding how hardwired circuits produce the flexible output needed for certain behaviours.

A deep-dive into fictive locomotion - a strategy to probe cellular activity during speed transitions in fictively swimming zebrafish larvae.

ABSTRACTFictive locomotion is frequently used to study locomotor output in paralyzed animals. We have evaluated the character of swim episodes elicited by different strategies in zebrafish. Motor output was measured on both sides of a body segment using electrodes and a pipeline for synchronizing stimulation and recording, denoising data and peak-finding was developed. The optomotor response generated swims most equivalent to spontaneous activity, while electrical stimulation and NMDA application caused various artefacts. Our optimal settings, optomotor stimulation using 5-day-old larvae, were combined with calcium imaging and optogenetics to validate the setup's utility. Expression of GCaMP5G by the mnx1 promoter allowed correlation of calcium traces of dozens of motor neurons to the fictive locomotor output. Activation of motor neurons through channelrhodopsin produced aberrant locomotor episodes. This strategy can be used to investigate novel neuronal populations in a high-throughput manner to reveal their role in shaping motor output. This article has an associated First Person interview with the first author of the paper.

Effects on the transient energy distribution of turbocharging mode switching for marine diesel engines

Nowadays, the high-power density and high efficiency of marine diesel engines make the requirements of high boost pressure and wide-range intake flow increased. In this study, a two-stage sequential turbocharging (TSST) system is presented as a method for increasing the power density and broadening the efficient working range of diesel engines. Through experimental and analysis methods, the relationships of intake and exhaust energy migration and exhaust energy distribution in the turbocharging mode switching process of the TSST system are investigated, and the optimal control strategy for the switching valves is obtained. The experimental results show that the optimized valve control strategy can achieve a reasonable distribution and efficient utilization of exhaust energy during the switching process. More specifically, the boost pressure error function is only 0.0003 kPa2·s, the engine speed fluctuation amplitude is less than 6 r/min, and the speed transition time is less than 8 s. A smooth switching between the turbocharging modes of the TSST system is achieved, exhaust energy loss is minimized, and the fuel economy and power performance of marine diesel engines over the entire range of operating conditions are effectively improved.

Building Standard Levels to Assess the Level of Some Elements of Fitness Related to Health among Junior Footballers

This study aimed to build standard levels to assess the level of some elements of physical fitness related to health among the juniors of Al-Faisali Football Club Academy, as well as to identify the differences in the tests due to the variable of height, weight and age. The researcher used a set of standardized tests that have a high degree of validity and reliability to measure the physical fitness elements of the subject of the study. The sample included (123) young players registered in the academy. The study reached to build standard levels for the juniors of the Al-Faisaly Football Club Academy, as well as the results of the study showed that there are differences between the averages of tests of explosive power, agility, transitional speed and grip strength of the right and left hand due to the variables of age, height and weight, while there were no differences in the 1000m running tests and the 30-second stomach repeat test due to the study variables. The study recommends building standard levels to measure the elements of fitness for other games, specifically for juniors.
 
 Received: 7 December 2021 / Accepted: 26 January 2022 / Published: 5 March 2022

5-nm Gate-All-Around Transistor Technology With 3-D Stacked Nanosheets

A comprehensive computational study of gate-all-around (GAA) devices with 3-D stacked silicon nanosheets (also known as nanoribbons or nanowires) is presented in this article. Technology development guidelines are provided for low-power applications in 5-nm CMOS technology node and beyond. The 3-D stacked nanosheet devices lower the subthreshold swing, drain-induced barrier-lowering, and subthreshold leakage current by up to 20.75%, 38.89%, and 88.53%, respectively, when compared to a silicon-on-insulator (SOI) FinFET with 5-nm physical gate length and identical silicon area at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {DD}} = {0.6}$ </tex-math></inline-formula> V and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T} = {80}\,\,^{\circ }\text{C}$ </tex-math></inline-formula> . The voltage gain of a minimum-sized CMOS inverter is increased by up to 157% with the 3-D stacked nanosheet devices, thereby providing robust operation with wider noise margins when compared to the SOI-FinFET technology. Furthermore, by scaling the supply voltage to 0.49 V, the energy consumption of a CMOS inverter is reduced by 53.81% with the GAA 3-D stacked nanosheet devices while providing similar output transition speed when compared to the SOI-FinFET technology.

Speed Marching in Military Boots: The Walk-To-Run Transition Speed and Vertical Ground Reaction Forces

Speed marching is the term for moving on foot, in which service members alternate marching and running to cover a certain distance in limited time. The standard load for speed marching is 25 kilograms, this includes a backpack, a tactical vest and rifle. When increasing walking speed, a person will switch from walking to running at a certain speed, this is called walk-to-run transition. The walk-to-run transition speed for marching in military boots, with or without a rifle, is unknown.

Convergence in suicide rates in FSU countries: a clustering approach

ABSTRACT This paper aims at identifying convergence clubs in suicide rates for a sample of 20 of FSU countries during the 1994–2016 period. A novel machine learning approach revels that while the null hypothesis of overall convergence has been rejected at the 5% significance level, there are four convergence clubs in the region. Within these clubs, different countries are on different transition paths and speeds of convergence, suggesting different policy interventions.

Turbidity currents on the open slope of the Fraser Delta

Turbidity currents have been observed and measured in submarine channels and canyons where the flows are confined, but with the exception of one serendipitous direct measurement, are only inferred to occur on unconfined delta slopes. In this paper, direct measurement of turbidity currents on the Fraser delta slope are reported and their dynamics compared to turbidity currents in channelized settings. Twelve turbidity current events occurring between May 2014 and June 2018 were identified from Acoustic Doppler Current Profiler instruments deployed at two sites (109 and 159 m water depth). All the events occurred in the months of May and June, in association with high spring river flow. Five of the events were recorded at both sites and the timing of first arrivals gives estimates of the current speed ranging from 0.4 to 3.6 m s−1. Direct current measurements confirm that most flow speeds exceed 1.5 m s−1, although one weak event did not exceed 0.4 m s−1. Current profiles indicate that the flows are of variable thickness, ranging from less than 3 m to 15 m. The turbidity current events varied in duration from 5 to 66 min and, in the cases where transit speeds were available, the durations were proportionally shorter when the transit speed was high. In stronger flows, the initial stage of the flow is highly variable, suggesting extreme turbulence, and the velocity structure of the flow is similar to previous experimental and field observations, with a distinctive relatively thin, high speed lower region being evident at times. Downslope translation of the instrument platform during two of the events suggest the presence of a dense basal layer up to 2.75 m thick, as suggested in the travelling wave model of Heerema et al. (2020). The fact that only approximately half the flows measured at the shallower site are observed at the deeper site suggest that the runout distances of open slope flows are limited. Weaker flows are barely distinguishable in speed and direction from ambient tidal velocities. Flow directions suggest that the open slope flows are unconfined and initiate in the upper slope area that is approximately the same as the area of upslope sediment waves. It is hypothesized that shallow gullies in the same area may be important for initiation and ignition of the flows that become unconfined on the lower part of the slope.

Bonding of cast iron-aluminum in bimetallic castings by high-pressure die casting process

A practical bimetallic casting consisting of aluminum matrix and cast iron inserts was manufactured via high-pressure die casting (HPDC) process. Different surface treatment methods for the cast iron inserts, including salt membrane plating and electrogalvanizing, were adopted to improve the bonding quality of bimetallic castings. Microstructure characterization on the bonding interface was conducted at different locations of bimetallic castings. Results indicate that compounds with flawless and continuously metallurgical bonding interface can be successfully fabricated by the HPDC process with the zinc rack plating treatment on the surface of cast iron inserts which results in a dense zinc coating with an average thickness of 8 μm. The melt flow speed and heat transition during solidification of the HPDC process are two key factors in determining the bonding integrity of bimetallic castings. With the dissolution and diffusion of the very thin zinc coating during solidification, there is no obvious aggregation of zinc element at the metallurgical bonding interface. Instead, a reaction layer with an irregular tongue-like morphology is formed with an average thickness of approximately 1 μm while it mainly consists of intermetallic phases Al60Cu30Fe10, Fe2Al5, and Al2FeSi.

Gravitational waves from bubble collisions in FLRW spacetime

Stochastic gravitational wave background (SGWB) is a promising tool to probe the very early universe where the standard model of particle physics and cosmology are connected closely. As a possible component of SGWB, gravitational waves (GW) from bubble collisions during the first order cosmological phase transitions deserve comprehensive analyses. In 2017, Ryusuke Jinno and Masahiro Takimoto proposed an elegant analysis approach to derive the analytical expressions of energy spectra of GW from bubble collisions in Minkowski spacetime avoiding large-scale numerical simulations for the first time [26]. However, they neglect the expansion of the universe and regard the duration of phase transitions as infinity in their derivation which could deviate their estimations from true values. For these two reasons, we give a new expression of GW spectra by adopting their method, switching spacetime background to FLRW spacetime, and considering a finite duration of phase transitions. By denoting σ as the fraction of the speed of phase transitions to the expansion speed of the universe, we find when σ is around mathcal{O} (10), the maxima of estimated GW energy spectra drop by around 1 order of magnitude than the results given by their previous work. Even when σ = 100, the maximum of GW energy spectrum is only 65% of their previous estimation. Such a significant decrease may bring about new challenges for the detectability of GW from bubble collisions. Luckily, by comparing new spectra with PLI (power-law integrated) sensitivity curves of GW detectors, we find that the detection prospect for GW from bubble collisions is still promising for DECIGO, BBO, LISA, and TianQin in the foreseeable future.

Whose express access? Assessing the equity implications of bus express routes in Montreal, Canada

Express buses—characterized by limited stops and sometimes higher frequencies or priority traffic measures—offer a cost-effective and efficient way to boost service convenience and reliability for riders. This paper assesses how the accessibility benefits of express bus route policy are distributed in Montreal, Canada, while providing a pathway for public transportation agencies to assess their policies and plans. To isolate the impact of bus express routes, we use General Transit Speed Specification (GTFS) data, the Open Trip Planner multimodal routing engine, and the 2013 edition of Montreal’s origin-destination survey to contrast travel time and accessibility at the trip and census-tract levels under two scenarios: one with the existing, complete network and the second a counterfactual scenario with no express bus routes. Our results indicate that bus express routes enable an overall increase in accessibility for the overall population. However, the accessibility benefits do not accrue evenly, as expected, but also tend to benefit a more significant number of higher incomes. This occurs despite the location of low-income populations in some outlying areas of the city, which express bus routes are supposed to serve. This paper closes with policy recommendations that help planners balance economic, environmental, and equity goals, perhaps one of the most complex challenges they face nowadays.

An engineering model for high-speed switching in GeSbTe phase-change memory

Ge2Sb2Te5 is the most successful phase-change alloy in non-volatile memory using the amorphous-crystal phase transition. In deriving further high performance in switching, especially the transition speed from amorphous to crystal should still be modified. In this work, we examined an ideal Ge2Sb2Te5 alloy based on the Kolobov model using ab-initio molecular dynamics simulations. As a result, it was clear that a uniaxial exchange between vacancies and Ge atoms plays a crucial role in realizing high-speed switching and a large contrast in the resonance bonding state in the alloy. The vacancy engineering enables the alloy switching speed to be extremely faster.

Transient Aeroelastic Response of a Rotor During Rotor Speed Transition in Forward Flight

Compound helicopters often have to reduce their rotor tip speeds to achieve higher forward speeds. The rotors, therefore, have to undergo a transient process of rotor speed changes. To investigate the transient loads and the related transformation from the rotating frame to the nonrotating frame, a rotor model is used to predict the transient aeroelastic responses. The rotor model is validated by using test data of a teetering model rotor during engagement and disengagement operations. The investigations indicate that a small transient lagwise root bending moment can result in a large transient contribution to rotor torque. This transient component is triggered by the force related with the sudden change of the angular acceleration of the rotor speed. Increasing the blade damping in the lagwise direction can significantly decrease the transient components of the lagwise root bending moment and the corresponding rotor torque. Making the angular acceleration continuous will not trigger the transient components, suggesting that this is a better way for the reduction of the transient rotor loads during speed changes.

Does Relative Age Affect Speed and Quality of Transition from School to Work?

Does Relative Age Affect Speed and Quality of Transition from School to Work?

Measurement of ice friction and aerodynamic drag for sliding on ice: Faster sliding in winter sports

This Method Article is co-submitted with the article Nr. JTRI_106967 in “Tribology International”. In the article we investigate the reasons behind a change in friction coefficient at low sliding velocities for a skeleton on ice. To complete the study a numerical model was created with air drag and the coefficient of friction in an equation representing sliding on ice. An experiment with two measurement systems, timing sensors on an ice track and a portable accelerometer at the base of the skeleton, was performed. A numerical model was amended with experimental data. Finally, changes of friction coefficient were analyzed, the difference in results provided by experiment and numerical calculations were illustrated, and conditions at the start when static friction transitioned to kinetic friction highlighted. The main findings about the methods used were as follows:• Portable accelerometer helped to define the speed for transition to smooth sliding;• The numerical model of time and velocity had greater error;• The numerical model of distance and velocity was very close to experimental results.

Lattice Boltzmann method based simulation of two dimensional bubble group ripening process

Ostwald ripening refers to a process of a particle/droplet/bubble system under local thermal equilibrium state adjusting the size distribution spontaneously to reduce the total surface energy. A lattice Boltzmann approach is used to simulate the ripening process of a two dimensional vapor bubble cluster dominated by phase transition kinetics. By comparing the numerical results with the theoretical prediction derived in two-dimensional space, it is shown that the lattice Boltzmann method is accurate in the simulations. The results also indicate that the mass transfer in liquid phase is driven by hydrodynamic pressure distribution and the hydrodynamic collapse of the bubbles influences the size distribution function in a small size region. The influence of the parameters in the equation of state of the material is studied further. A positive relation between phase transition speed and specific internal energy is proposed, which enhances the thermal fundamental of phase transition.

Lattice Boltzmann Simulation on Two Dimensional Vapour Bubble Ripening

Ostwald ripening refers to a process of a particle/droplet/bubble system under thermal equilibrium state adjusting the size distribution spontaneously to reduce the total surface energy. With knowing lack in numerical studies, a lattice Boltzmann approach is used to simulate the ripening process of two dimensional vapour bubble cluster dominated by phase transition kinetics. By comparing the numerical results with the theoretical prediction derived in two dimensional space, it is shown that the lattice Boltzmann method is accurate in the simulations. The results also indicate that the mass transfer in liquid phase is driven by hydrodynamic pressure distribution and the hydrodynamic collapse of bubbles influences the size distribution function in small size region. The impact of the parameters of the equation of state of the material is studied further. A positive relation between phase transition speed and specific internal energy is proposed, which enhances the thermal fundamental of phase transition.

Calculation Method of Cutter Location Points Considering Corner Transition Speed in Cnc

Calculation Method of Cutter Location Points Considering Corner Transition Speed in Cnc

Impact of the Connected Vehicles Penetration Rate on the Speed Transition Matrices Accuracy

The development of the Vehicle to Everything (V2X) communication technology can provide crucial data for traffic analysis on the microscopic level. Real-time data from Connected Vehicles (CVs) opens new research possibilities providing detailed insight into the actual traffic state. Speed Transition Matrices (STMs) can be used for this insight and can be created within a fully observable traffic environment. By introducing CVs into the traffic network, it is possible to obtain a partial observation of the traffic environment. This paper explores how the data collected from CVs can be used for the creation of STMs at an isolated intersection in a simulated environment. An emphasis is given on how the CVs penetration rate impacts the accuracy of the created STM. The results show that by increasing the CVs penetration rate, the STM estimate accuracy is also increased, although the relation between estimate accuracy and the penetration rate is not linear. Obtained results show that the error of STM estimation rapidly decreases in the lower CVs penetration rate range.