Transition Speed Research Articles

The influence of government affiliations on firm product innovation in a dynamic institutional environment: insights from China

PurposeBuilding on resource dependence theory and the dynamic institution-based view, this paper examines the influence of government affiliations on firm product innovation in a dynamic institutional environment.Design/methodology/approachUsing unique panel data of Chinese manufacturing firms covering a period of 12 years (1998–2009) with 2,564,547 firm-year observations, this study chooses the panel Tobit model with random effects to explore the influence of government affiliations on firm product innovation, followed by an analysis to test the moderation effects of dynamic institutional environments.FindingsThe study findings suggest that Chinese firms with higher-level government affiliations have a relatively high product innovation performance. It finds that this innovation stimulating effect is contingent on the dynamic nature of the institutional environment. To be specific, a high speed of institutional transition may depress the positive innovation effects of government affiliations, while a more synchronized transition speed of institutional components may enhance the positive innovation effects of firms' government affiliations.Originality/valueThis study adds to a better understanding of the drivers of product innovation in Chinese firms that are situated in environments that are characterized by institutional change, using and contributing to resource dependence theory and the dynamic institution-based view.

Transit Arrival Time Prediction Using Interaction Networks

Accurate transit arrival time prediction is a critical factor for improving the quality of transit services. A significant factor that can affect transit arrival times is the other vehicles traveling on transit routes, as transit arrival time is significantly affected by traffic conditions. However, few previous studies considered traffic condition impacts in transit arrival time prediction due to a lack of real-time traffic data, reducing the accuracy in predictions under varying traffic conditions. To fill this research gap, crowdsourced speed data with wide coverage is utilized to indicate traffic conditions and to predict transit arrival time in conjunction with General Transit Feed Specification (GTFS) data. Interaction Networks (INs) are employed to model the interactions between transit speed, dwell time, and traffic speed for arrival time prediction. The proposed method only uses limited historical data and can predict arrival time at stops along a transit route. Ten days of data were collected from bus route #4 in Tucson, Arizona to evaluate the performance of the proposed method. The evaluation results show the average mean absolute percentage error (MAPE) of predicted arrival time on weekdays and weekends is 13.5% and 14%, respectively, indicating that the proposed method is promising for predicting transit arrival time while considering real-time traffic conditions. Furthermore, six traditional methods are compared with the proposed method, and the comparison results show the proposed method outperforms the other six methods.

Deployment of biologging tags on free swimming large whales using uncrewed aerial systems.

Suction-cup-attached biologging tags have led to major advances in our understanding of large whale behaviour. Getting close enough to a whale at sea to safely attach a tag is a major limiting factor when deploying these systems. Here we present an uncrewed aerial system (UAS)-based tagging technique for free-swimming large whales and provide data on efficacy from field testing on blue (Balaenoptera musculus) and fin (B. physalus) whales. Rapid transit speed and the bird's-eye view of the animal during UAS tagging contributed to the technique's success. During 8 days of field testing, we had 29 occasions when a focal animal was identified for attempted tagging and tags were successfully attached 21 times. The technique was efficient, with mean flight time of 2 min 45 s from launch to deployment and a mean distance of 490 m from the launch vessel to tagged animal, reducing potential adverse effects resulting from close approaches for tagging. These data indicate that UAS are capable of attaching biologging tags to free-swimming large whales quickly and from large distances, potentially increasing success rates, decreasing attempt times, and reducing animal disruption during tagging.

Ultrafast Shape‐Reconfigurable Chiral Mechanical Metamaterial based on Prestressed Bistable Shells

AbstractFast shape‐reconfiguration with large morphing amplitude is crucial for intelligent materials/structures that require tunable functions and adaptivity to different environments. However, the morphing strategies are rare in combining ultrafast speed, large amplitude, and high energy‐efficiency simultaneously. Herein, a class of 2D and 3D chiral mechanical metamaterials are proposed to tackle this challenge based on prestressed bistable metallic shells. The metamaterial is architected by cylindrical cores and slender bistable shells with an anti‐chiral arrangement. The bistable shell has a flat extended shape and a rolled‐up shape that can wrap on the connected cylindrical cores compatibly, and thus endow the metamaterials with a tunable morphing amplitude that can even extend to infinity. By experiments, simulations and theoretical modelling, it is demonstrated that the bistable shell can transform from the extended state to the rolled‐up state with a transitional speed of 7.56 m s−1, which provides the 2D and 3D metamaterials with 25.38‐ and 101.14‐times body area/volume variation per second, respectively. Moreover, a smart trapper for capturing moving objects and a phononic structure with tunable band gaps are realized based on the metamaterials. This work provides a straightforward platform to design metamaterials and their derived systems with ultrafast and large‐amplitude shape‐reconfigurability.

Photobiomodulation in Alzheimer's Disease-A Complementary Method to State-of-the-Art Pharmaceutical Formulations and Nanomedicine?

Alzheimer's disease (AD), as a neurodegenerative disorder, usually develops slowly but gradually worsens. It accounts for approximately 70% of dementia cases worldwide, and is recognized by WHO as a public health priority. Being a multifactorial disease, the origins of AD are not satisfactorily understood. Despite huge medical expenditures and attempts to discover new pharmaceuticals or nanomedicines in recent years, there is no cure for AD and not many successful treatments are available. The current review supports introspection on the latest scientific results from the specialized literature regarding the molecular and cellular mechanisms of brain photobiomodulation, as a complementary method with implications in AD. State-of-the-art pharmaceutical formulations, development of new nanoscale materials, bionanoformulations in current applications and perspectives in AD are highlighted. Another goal of this review was to discover and to speed transition to completely new paradigms for the multi-target management of AD, to facilitate brain remodeling through new therapeutic models and high-tech medical applications with light or lasers in the integrative nanomedicine of the future. In conclusion, new insights from this interdisciplinary approach, including the latest results from photobiomodulation (PBM) applied in human clinical trials, combined with the latest nanoscale drug delivery systems to easily overcome protective brain barriers, could open new avenues to rejuvenate our central nervous system, the most fascinating and complex organ. Picosecond transcranial laser stimulation could be successfully used to cross the blood-brain barrier together with the latest nanotechnologies, nanomedicines and drug delivery systems in AD therapy. Original, smart and targeted multifunctional solutions and new nanodrugs may soon be developed to treat AD.

Turn-taking in human face-to-face interaction is multimodal: gaze direction and manual gestures aid the coordination of turn transitions.

Human communicative interaction is characterized by rapid and precise turn-taking. This is achieved by an intricate system that has been elucidated in the field of conversation analysis, based largely on the study of the auditory signal. This model suggests that transitions occur at points of possible completion identified in terms of linguistic units. Despite this, considerable evidence exists that visible bodily actions including gaze and gestures also play a role. To reconcile disparate models and observations in the literature, we combine qualitative and quantitative methods to analyse turn-taking in a corpus of multimodal interaction using eye-trackers and multiple cameras. We show that transitions seem to be inhibited when a speaker averts their gaze at a point of possible turn completion, or when a speaker produces gestures which are beginning or unfinished at such points. We further show that while the direction of a speaker's gaze does not affect the speed of transitions, the production of manual gestures does: turns with gestures have faster transitions. Our findings suggest that the coordination of transitions involves not only linguistic resources but also visual gestural ones and that the transition-relevance places in turns are multimodal in nature. This article is part of a discussion meeting issue 'Face2face: advancing the science of social interaction'.

Calculation method of cutter location points considering corner transition speed in CNC

The calculation method of cutter location (CL) points only considers the geometric errors, but cannot consider the requirements of the corner transition algorithm in CNC, which results in the smoothing algorithm in the CNC not playing a maximum role or even failing. To solve this problem, a calculation method of the CL points considering corner transition speed in CNC is proposed. Firstly, the key geometric parameters of the CL points that affect the corner speed are analyzed. Secondly, according to the analysis results, the objective function is established to connect the CL points calculation in CAM and the corner transition speed in CNC. By solving the objective function, the calculation method of the CL points is developed. Finally, the effectiveness of this method is verified by experiment. Comparing with the commonly used iso-chord height method, the proposed method can increase the speed at the corner of the CL points and reduce the acceleration and jerk at the same time. By the proposed method, the tracking accuracy, trajectory accuracy, and machining efficiency can be significantly improved. The proposed method can be integrated into CAM software to generate high quality CL points.

Relation analysis of ship speed & environmental conditions: Can historic AIS data form a baseline for autonomous determination of safe speed?

AbstractAs no internationally agreed-upon method for determining safe speed values currently exists, collecting vast amounts of information on conventional ship behaviour could be used to train autonomous ship intelligence in determining safe speeds in different conditions. This requires speed data collected from conventional ships to resemble what can be described as safe speeds. To test this, the Automatic Identification System (AIS) and environmental data – namely visibility, mean wind speed and significant wave height – were collected and merged for two study areas in Norway in the period between 27 March 2014 and 1 January 2021. Regression analyses based on 47,490 unique vessel transits were conducted and supplemented by two graphical methods for revealing relationships between variables. Contrary to the contemporary understanding of safe speed, reduced visibility did not lead to significantly reduced transit speeds. Wind and waves caused a reduction in speed in the open ocean, but not in coastal waters. Transit speeds were lower in coastal waters than in the open ocean.

Correlating 3D printing performance with sol-gel transition based on thermo-responsive k-carrageenan affected by fructose

Thermo-responsive food inks occupy an important part of 3D food printing materials. A great challenge of their accurate 3D printing is to ensure sol-gel transition is adapted to 3D printing process. In this study, k -carrageenan (KG) incorporated with fructose (0–30%, w/v) was selected as a representation of thermo-responsive inks, and their interactive mechanism was investigated. Sol-gel transition and rheology were correlated with 3D printing process in terms of extrusion stage, formation stage, and self-supporting stage. Results indicated that fructose addition increased ink's gelation temperature (Tg) and affected printing temperature selection. During extrusion stage, ink in sol-state with a low viscosity was desirable to enable proper extrudability. While, during formation stage, sol-gel transition speed (gelation time) was important for extruded ink to solidify to avoid continuous spreading. Increased elastic modulus (G′) with fructose addition was beneficial for printed structures to be self-supportable during self-supporting stage. Low field nuclear magnetic resonance (LF-NMR) indicated that water mobility was increasingly restricted with addition of fructose. Hydrogen bond, hydrophobic and electrostatic interactions all significantly affected the KG/fructose ink. Scanning electron microscopy (SEM) suggested that fructose addition resulted in a denser network structure. This study would provide insights on 3D printing of thermo-responsive food inks by correlating with sol-gel transition. • 3D printing behavior was correlated with sol-gel transition process. • 3D printing was divided into three stages and correlated with rheology change. • Fructose addition increased Tg, gelation speed and resultant 3D printing behavior.

A simple model of human walking

Aim. We investigate Alexander’s inverted pendulum model, the simplest mathematical model of human walking. Although it successfully explains some kinematic features of human walking, such as the velocity of the body's centre of mass, it does not account for others, like the vertical reaction force and the maximum walking speed. This paper aims to minimally extend Alexander’s model in such a way as to make it a viable and quantitative model of human walking for clinical biomechanics.Material and methods. In order to compare the predictions of Alexander’s model with experimental data on walking, we incorporate in it a robust phenomenological relation between stride frequency and stride length derived in the literature, and we introduce a step-angle dependent muscle force along the pendulum. We then analytically solve the pendulum's motion equation and find the corresponding analytical expression for the average walking speed.Results. The values of the average walking speed for different heights predicted by our model are in excellent agreement with the ones obtained in treadmill experiments. Moreover, it successfully predicts the observed walking-running transition speed, which occurs when the stride length equals the height of an individual. Finally, our extended model satisfactorily reproduces the experimentally observed ground reaction forces in the midstance and terminal stance phases. Consequently, the predicted value of the (height-dependent) maximum walking speed is in reasonable agreement with the one obtained in more sophisticated models of human walking.Conclusions. Augmented with our minimal extensions, Alexander’s model becomes an effective and realistic model of human walking applicable in clinical investigations of the human gate.

Applying an ecosystem lens to low-carbon energy transitions: A conceptual framework

Business model innovations aiming at systemic change influence the speed and direction of low-carbon transitions, thus supporting public decarbonization policies. However, their potential is often limited by institutional settings or a lack of alignment with potential partners. Therefore, to exploit the potential for systemic change of business model innovations in socio-technical systems, it is necessary to consider their interactions with their wider environment. In this conceptual study, we explore the mechanisms through which business activities interact with public policy goals under low-carbon energy transitions. We take an ecosystem lens to analyze value creation at the levels of customers, business, inter-organizational networks and the public. Based on an integrative literature review, we build a conceptual meta-model specifying the constitutive elements, dynamics and environmental dimensions describing regional energy ecosystems under transition. The main constitutive element of the ecosystem is the value network, i.e. the interlinked business models of collaborating organizations exchanging money, goods, services, information or intangible benefits. The value network interacts dynamically with a pool of resources (assets, capabilities and intangible resources) that improves the ecosystem's ability to enact systemic change. Orchestration is a crucial process to steer the ecosystem's development towards creating value for customers as well as for the public. Finally, the relevant environmental dimensions include policy, culture, markets, industry structure as well as potential future members or resources. We illustrate our conceptual model with the case of the development of low-carbon district heating to decarbonize space heating in a Swiss city. This illustrative case study shows that the ecosystem perspective combined with public value theory is well suited to describe the dynamics of a low-carbon energy transition and provides valuable insights on the prospects of novel business models.

Evaluation of the deformation index of sea urchin Echinometra vanbrunti ovules by microfluidics

Microfluidics is a technique for controlling the flow of liquids in micrometric-scale channels, it is a powerful tool for performing analyzes with high throughput, high sensitivity, and speed, as well as low cost. In cells, the deformation index (DI) is one of the parameters that can be analyzed by this technique. Cell deformation is linked to the structure and mechanical properties of the biological constituents. By passing cells through a narrow channel, they are dynamically deformed, this can be done by a precise control of the pressure in the system. In this study, the ovule of the sea urchin Echinometra vanbrunti was used since it is a model cell due to its circularity very close to one. The average size of the cells (62.67 ± 2.91 μm) was analyzed to determine the appropriate size of the microchannels and to be able to manufacture a functional device to carry out the experiment. The device was manufactured based on polydimethylsiloexane (PDMS). Each experiment was digitally recorded to later be processed with Tracker modeling software and finally the data analysis was done with R program from which parameters such as DI, transit times in the channel and transit speed were obtained and searched for a relationship between the initial diameter of the cells and the transit time. We found a maximum DI of 0.698, a minimum transit time of 3.6 s and a maximum of 296.3 s, in addition, three different behaviors in the DI were found.

Voltage-dependent transitions between resting and activated states of the four Cav1.1 voltage sensors observed in MD simulation.

The sliding helix hypothesis describes how, upon depolarization and repolarization of the membrane, the positive gating charges of the S4 helices of voltage-sensing domains (VSDs) one by one move across the membrane electrical field and thereby effect the opening and closing of ion channels. Voltage-gated calcium channels contain four VSDs, which together regulate gating of a common pore. Although these four VSDs are highly homologous, they differ from each other, e.g. in the number of gating charges and in the number and position of their countercharges. Recent atomic-resolution structures of voltage-gated calcium and sodium channels delineate the endpoints of the VSD movement upon depolarization, showing the S4 helix in the activated up-state. While the first structures of VSDs in resting states have been solved for homotetrameric (prokaryotic) channels, resting state structures of the (pseudo-)heterotetrameric eukaryotic sodium and calcium channels are still lacking. Accordingly, structural models showing the transitions from the resting to the activated state and back are still elusive. Here we addressed this problem using enhanced sampling molecular dynamics simulations of the CaV1.1 calcium channel exposed to a strong membrane potential. Indeed, starting from the known up-state, the S4 helices of the four VSDs moved down to positions closely matching the experimentally determined resting state of the bacterial NaVAb channel. Importantly, the trajectories, the transiently formed ionic interactions between gating- and countercharges, and the speed of the S4 transitions differed substantially between the four VSDs. This is consistent with data from recent mutagenesis and voltage-clamp fluorometry studies on CaV1.1 and allows relating the individual VSD movements with their putative roles in the regulation of distinct channel gating properties, as well as their role in the activation of excitation-contraction coupling in skeletal muscle.

Vibroacoustic Therapy in Parkinsonian Patients. A Complementary Approach to Improve Rehabilitation Outcome

Background: Parkinson’s Disease (PD) is a chronic progressive neurodegenerative disorder with motor and non-motor symptoms. Rehabilitation represents an adjuvant intervention to pharmacological and surgical therapy. Our study aim was to investigate the effectiveness of the Vibroacoustic Therapy (VAT) according to the Metodo Magic Music combined with conventional Training (Tr) versus Tr alone in improving motor symptoms and postural control in PD patients. Methods: Twenty-four patients with idiopathic PD were enrolled. They were randomly assigned to the Tr-VAT or the Tr group. Total intervention time was 40 min (Tr) and 60 min (Tr-VAT) 3 times a week for 3 months. Both groups carried out at baseline and follow-up clininetric scales and tests to assess clinical outcome. Speed of postural transitions and gait parameters (endurance and comfortable and fast speed) have been measured. Results: Follow-up evaluation showed in PD patients from the Tr-VAT group as compared to those from the Tr group an improvement of postural control assessed with Berg Balance Scale (p = 0.054) and Timed-Up and Go test (TUG) test (p = 0.058). Moreover, significant (p < 0.05) differences between groups were found for comfortable gait speed (p = 0.004) and speed of postural changes - from right side to supine (p = 0.03), from supine to right and left side (p = 0.01), from supine to prone (p = 0.002) and supine to sitting (p = 0.005), respectively. Conclusions: Our study demonstrated the effectiveness of VAT as complementary treatment with conventional rehabilitation approaches, by improving mobility, agility and motor flexibility in PD patients.

Development of a Method for Selecting Bus Rapid Transit Corridors Based on the Economically Viable Passenger Flow Criterion

The creation of bus rapid transit systems requires significant investments in transport infrastructure. It often requires changes in roadway parameters, building boarding platforms, new bus depots, as well as creating a priority passage system at intersections with individual vehicles flows. In world practice, the routing of bus rapid transit (hereinafter—BRT) corridors is often based on the criterion of an opinion of transport experts who assess passenger flows and the location of main attraction points. This article describes an algorithm for building BRT corridors based on the criterion of economically viable passenger flow. The method is based on an iterative algorithm built on the principle of passenger flows redistribution over the transport network in the event of a change in its characteristics. Specifically, what changes is the speed of transit in certain areas due to inclusion of the area in a BRT corridor when the area reaches the threshold of economically viable passenger flow. A threshold value of passenger flow for different cities, grouped by population size, is determined on the basis of passenger flow statistics in globally operated BRT systems. The condition for exiting the iterative algorithm can be either the absence of new network areas where an economically viable passenger flow is achieved, or the achievement of 90% of the labor commuting share in the city during the time specified in the urban planning standard. This method can be used to identify new and extend existing BRT corridors in cities with populations from 100 to 2000 thousand people.

Using minimal clinically important differences to measure long-term transitions of osteosarcopenia: The New Mexico Aging Process Study

Background/objectiveBy having a better understanding of transitions in osteosarcopenia, interventions to reduce morbidity and mortality can be better targeted. The aim of this study was to show the rationale and method of using minimal clinically important differences (MCID's) to classify transitions, and the effects of demographic variables on transitions in a 9-year follow-up data from the New Mexico Aging Process Study (NMAPS). MethodsTransitions were identified in four aspects of osteosarcopenia: bone mineral density (BMD), appendicular skeletal muscle mass/body mass index ratio (ASM/BMI), grip strength and gait speed. Transitions were identified using a MCID score. As there is currently no available MCID for BMD and ASM/BMI, those were determined using a distribution-based and an anchor-based method. Total transitions were calculated for all four measures of osteosarcopenia in all transition categories (maintaining a health status, beneficial transition, harmful transitions). Poisson regression was used to test for effects of demographic variables, including age, sex, physical activity, medication, and health status, on transitions. ResultsOver the 9-year follow-up, a total of 2163 MCID-derived BMD transitions were reported, 1689 ASM/BMI transitions, 2339 grip strength transitions, and 2151 gait speed transitions. Additionally, some MCID-derived transition categories were associated with sex, age, and health status. ConclusionUse of MCID-derived transitions reflected the fluctuation and the dynamic nature of health in older adults. Future research should focus on transitions of modifiable markers in osteosarcopenia to design intervention trials.

Microscopic dynamics and Bose–Einstein condensation in liquid helium

We review fundamental problems involved in liquid theory including both classical and quantum liquids. Understanding classical liquids involves exploring details of their microscopic dynamics and its consequences. Here, we apply the same general idea to quantum liquids. We discuss momentum condensation in liquid helium which is consistent with microscopic dynamics in liquids and high mobility of liquid atoms. We propose that mobile transit atoms accumulate in the finite-energy state where the transit speed is close to the speed of sound. In this state, the transit energy is close to the oscillatory zero-point energy. In momentum space, the accumulation operates on a sphere with the radius set by interatomic spacing and corresponds to zero net momentum. We show that this picture is supported by experiments, including the measured kinetic energy of helium atoms below the superfluid transition and sharp peaks of scattered intensity at predicted energy. We discuss the implications of this picture including the macroscopic wave function and superfluidity.

Game-Theory-Based Mode Switch Control Schedule Design for Variable Cycle Engine

The variable cycle engine selects the appropriate working mode through mode switch to meet the requirements of low specific fuel consumption and high unit thrust. When the variable cycle engine switches between different modes, it should ensure the smooth transition of working modes and obtain the expected performance at the same time. Consequently, a general control schedule design method for mode switch is investigated in this paper. The feasible switching domains of single-bypass working mode and double-bypass working modes are obtained based on multifurcating tree traversal, and the switching point in the feasible switching domain is determined by solving the collaboration-game optimization problem based on sequential quadratic programming (SQP). Finally, the schedule of control variables is designed to realize smooth and fast switching between different working modes of variable cycle engine. The simulations show that based on the general control schedule of mode switch proposed in this paper, smooth transition of thrust and rotor speed can be achieved under the premise of safe engine operation, with small fluctuations and a short switching time, which is about 2.5 s.

1326 IMPROVING THE QUALITY OF BOWEL CARE ON GERIATRIC WARDS BY INCREASING COMPLIANCE OF DAILY DOCUMENTATION OF BOWEL MOTIONS

Abstract Introduction Bowel health is affected in acutely admitted patients due to illness, change in diet, dehydration, and reduced mobility. Constipation is common and older patients are particularly at risk of constipation due to reduced bowel transit speed. Bowel motion monitoring can help improve bowel health and reduce complications including delirium, which can prolong hospital admission. To increase detection of constipation, a quality improvement project was carried out in the Department of Medicine for the Elderly at Southend Hospital, with aims to increase compliance of daily stool chart entries. Early detection will prompt patient review, investigation, and treatment of constipation, thereby managing symptoms and preventing complications. Method Stool charts of patients across the geriatric wards were reviewed weekly for daily entries up to the last 7 days of their admission. Baseline compliance was determined on day 0 by dividing total days of stool chart entries over total days of admission (up to 7 days). Patients newly admitted or transferred to the ward on the day of stool chart review were excluded from the data. Interventions included verbal reminders to stakeholders (nurses, HCAs, doctors) at morning handovers, an electronic reminder with emails to stakeholders, and lastly a visual reminder with copies of a poster around the ward. The interventions were implemented separately on a weekly basis to quantify their effectiveness on compliance through further stool charts reviews on days 7, 14 and 21, and compared to baseline data. Results Overall compliance increased by 16.9%, and the largest improvement was in response to the poster strategically placed next to all patient charts. Conclusion The QIP was time and resource efficient, helping to identify constipation early and flag patients at risk for or for treatment of constipation. It is also easily repeatable and similar principles can be applied across other wards and specialties.

The role of pore fluids in supershear earthquake ruptures

The intensity and damage potential of earthquakes are linked to the speed at which rupture propagates along sliding crustal faults. Most earthquakes are sub-Rayleigh, with ruptures that are slower than the surface Rayleigh waves. In supershear earthquakes, ruptures are faster than the shear waves, leading to sharp pressure concentrations and larger intensities compared with the more common sub-Rayleigh ones. Despite significant theoretical and experimental advances over the past two decades, the geological and geomechanical controls on rupture speed transitions remain poorly understood. Here we propose that pore fluids play an important role in explaining earthquake rupture speed: the pore pressure may increase sharply at the compressional front during rupture propagation, promoting shear failure ahead of the rupture front and accelerating its propagation into the supershear range. We characterize the transition from sub-Rayleigh to supershear rupture in fluid-saturated rock, and show that the proposed poroelastic weakening mechanism may be a controlling factor for intersonic earthquake ruptures.