Mobility Distribution Research Articles

School District Housing Buyers and Educational Investment Returns: A Case Study of X District in Shanghai

As a dual carrier of educational resources and economic assets, school district housing has become an important tool for family educational investment and social class reproduction. This paper takes Shanghai's X District as an example to explore, from a sociological perspective, the purchasing behaviors of different groups regarding school district housing and their educational investment returns. It reveals the key role of school district housing in the accumulation of cultural and social capital. The study finds that high-income families, the middle class, and the working class in X District exhibit different demand tendencies when purchasing school district housing, reflecting goals of obtaining high-quality educational resources, expanding social capital, and achieving upward social mobility, respectively. The phenomenon of school district housing exacerbates the imbalance in the distribution of educational resources and limits social mobility.

Comparison between carrier transport property and crystal quality of TlBr semiconductors

Thallium bromide (TlBr) semiconductor detectors are being developed as promising candidates for high-detection-efficiency, high-energy-resolution, and room-temperature gamma-ray spectrometers. This study presents methods for evaluating TlBr crystal quality and carrier transport characteristics using neutron Bragg-dip imaging and the time-of-flight method for pulsed-laser-induced carriers, respectively. Neutron Bragg-dip imaging effectively determines the crystal orientation distribution, revealing crystal imperfections and grain boundaries. Time-of-flight measurements provide a spatial distribution of carrier mobility. In this study, two samples obtained from both the upstream and downstream region in the crystal ingot were evaluated. Although both samples show similar crystal quality, the upstream sample showed high carrier mobility across all areas, whereas the downstream sample exhibits low mobility in some areas. These findings suggest that, at least within the range of carrier mobility currently obtained, the effect of crystal integrity on carrier mobility is less significant than that of impurities. In conclusion, combining neutron Bragg-dip imaging with carrier mobility measurements offers a comprehensive approach to evaluating and improving TlBr detectors.

Operando Decoding Ion-Conductive Switch in Stimuli-Responsive Hydrogel by Nanodiamond-Based Quantum Sensing.

Thermal-responsive hydrogels are developed as ion-conductive switchs for energy storage devices, however, the molecule mechanism of switch on/off remains unclear. Here, poly(N-isopropylacrylamide-co-acrylamide) hydrogel is synthesized as a model material and nanodiamond (ND) based quantum sensing for phase change study is developed. First, micro-scale phase separation with cross-linked mesh structure after sol-gel transition is visualized in situ and water molecules are trapped by polymer chains and on a chemically "frozen" state. Then, the nano-scale inhomogeneous distributions of viscosity, thermal conductivity and ionic mobility in hydrogel at high temperature are observed by measuring the rotation, translation and zero-field splitting of NDs. Besides, the ionic mobility of hydrogel is found to be dependent not only on temperature but also on polymer concentration. These observations suggested that the physical "wall" induced by inhomogeneous phase separation at microscopic scale blocked the ion conduction pathways, providing a potential intrinsic explanation for ion migration shut-down of ionic hydrogels at high temperature.

Quantifying spatial interaction centrality in urban population mobility: A mobility feature- and network topology-based locational measure

Spatial interaction centrality reflects the relative importance of population mobility within a location in urban population mobility. Population mobility networks visually represent urban population mobility, with mobility features and network topology contributing to the quantification of spatial interaction centrality of locations (i.e., geographical nodes). However, existing centrality measures rarely consider mobility features and network topology simultaneously. Centrality quantification also ignores the differences in distance effects between long- and short-distance trips. These factors have led to the inaccurate quantification of centrality. We propose an algorithm called k-dis-weight-shell that quantifies the spatial interaction centrality of geographical nodes at different spatiotemporal scales. Considering the different effects of distance on long- and short-distance trips, we use a spatial continuous wavelet transformation to estimate the radiation radius of geographical nodes. Then, by combining network topology with mobility features (mobility distance and flow), the algorithm transforms them into a ranked order of spatial interaction centrality. Tested in Wuhan and Chengdu, our algorithm outperforms six existing benchmarks. For cases in urban planning and epidemic management, results show that k-dis-weight-shell effectively distinguishes similarities and differences between the distribution of population mobility's spatial interaction centrality and the urban center hierarchy at a coarse spatiotemporal scale. Additionally, it reveals a double wave phenomenon of spatiotemporal correlation between population mobility and COVID-19 transmission before and after lockdown at a fine spatiotemporal scale.

Distributional equity impacts of automated vehicles: A disaggregated approach

Better understanding of the equity impacts of automated vehicles (AV) is needed to design equitable deployment plans for AV technology. The goal of this study was to develop and demonstrate a modeling framework to support distributional equity assessments of AV systems prior to their wide adoption. This modeling framework takes a disaggregated approach that integrates agent-based simulation, diverse transportation outcomes, and equity analyses. The framework uses individual-level data to capture detailed disparities in transportation outcomes, applies a state-of-the-art multi-agent traffic simulation model (MATSim) to simulate privately-owned and shared AVs simultaneously, and considers distributional equity from multiple perspectives. To test and demonstrate the framework, a case study was conducted for the Tampa Bay region. Five scenarios were considered with different AV market shares and integration strategies based on scenario planning by the U.S. Federal Highway Administration. Results reveal that high AV penetration rates were required for substantial reductions in inequality. The introduction of AVs led to a more even distribution of accessibility, but slightly more uneven distribution of traditional mobility and affordability. Impacts of disparities in outcomes for disadvantaged groups were mixed. These results suggest that AVs will likely perpetuate existing inequity in the transportation system as long as its fundamental structure remains the same as today. Results highlight the importance of planning and design strategies that directly address the distributional impacts to ensure that AV technology is deployed equitably.

Cascading consequences of structural interventions in a tropical wandering gravel‐bed river

AbstractRiverscapes are often modified and managed through ‘command and control’ structural engineering approaches. These structures not only alter flow and sediment transport patterns but also negatively affect riverscape biodiversity. These impacts are particularly acute for rivers that are characterised by high mobility and wide flow distribution during extreme events. We used hydrodynamic and geomorphological change assessment to appraise the impacts of existing flood structures and their potential for removal in a tropical wandering gravel‐bed river in the Philippines. Our approach informs a systematic decision‐making process to screen opportunities for channel reconnection. Two‐dimensional hydraulic modelling showed flood structures confine flood water within the active channel for more frequent flood events, but banks are overtopped during larger magnitude events (>50‐year recurrence interval). Incorporating modelling results, a multi‐criteria analysis was developed to appraise opportunities for river reconnection based on structure purpose, functionality, and local land‐use. We differentiate among four actions for each structure: removal, redesign, set back, or retention. One structure is recommended for removal because it cuts off an anabranch, reduces channel capacity, and increases main anabranch bed shear stress. Increased potential for bed and bank erosion due to the structure's presence had a cascading effect, resulting in further interventions downstream and on the opposite bank. We show how the use of system‐scale two‐dimensional hydraulic modelling alongside high‐resolution topographic mapping can support management of interventions to reconnect a river to its wider anabranch‐bar morphology. Such actions form part of proactive, adaptive, and nature‐based flood management plans with local and non‐local benefits.

Conflicts Resolution in Mobile Distributed Real-Time Database Systems: Issues and Challenges

Conflicts Resolution in Mobile Distributed Real-Time Database Systems: Issues and Challenges

Effect of chemical modification on the distribution of electrophoretic mobilities of individual molecules of E. coli β-galactosidase

Escherichia coli β-galactosidase was labelled with 1 mmol/L fluorescein 5-carbamoylmethylthiopropanoic N-hydroxysuccinimidyl ester for 1 and 3 min. The samples were separated by capillary electrophoresis and peak areas compared to that of labelled BSA for the purpose of quantification of the concentration of attached label. Enzyme concentration in the samples was determined by single molecule counting. The average number of labels attached to each molecule of enzyme was found to be 3.1 and 4.5 when labelled for 1 and 3 min, respectively. The distribution of single enzyme molecule electrophoretic mobilities for the unlabelled enzyme and that labelled for 1 and 3 min were measured using capillary electrophoresis. The average mobilities were found determined to be −(1.99 ± 0.13) × 10–8 m2 V−1 s−1 ( N = 39), −(2.16 ± 0.19) × 10–8 m2 V−1 s−1 ( N = 46), and –(2.18 ± 0.21) × 10–8 m2 V−1 s−1 ( N = 39), respectively. A protein electrophoresis model was applied and predicted that the differences in average mobilities could be explained through relatively minor changes in overall charge, Stokes radius, and shape. This difference was similar to the range in mobilities observed in the unlabelled protein. This is consistent with the electrophoretic heterogeneity of the unmodified enzyme being caused by relatively small differences in charge, size, and shape of the individual molecules in the population.

Marangoni Droplets of Dextran in PEG Solution and Its Motile Change Due to Coil-Globule Transition of Coexisting DNA.

Motile droplets using Marangoni convection are attracting attention for their potential as cell-mimicking small robots. However, the motion of droplets relative to the internal and external environments that generate Marangoni convection has not been quantitatively described. In this study, we used an aqueous two-phase system [poly(ethylene glycol) (PEG) and dextran] in an elongated chamber to generate motile dextran droplets in a constant PEG concentration gradient. We demonstrated that dextran droplets move by Marangoni convection, resulting from the PEG concentration gradient and the active transport of PEG and dextran into and out of the motile dextran droplet. Furthermore, by spontaneously incorporating long DNA into the dextran droplets, we achieved cell-like motility changes controlled by coexisting environment-sensing molecules. The DNA changes its position within the droplet and motile speed in response to external conditions. In the presence of Mg2+, the coil-globule transition of DNA inside the droplet accelerates the motile speed due to the decrease in the droplet's dynamic viscosity. Globule DNA condenses at the rear part of the droplet along the convection, while coil DNA moves away from the droplet's central axis, separating the dipole convections. These results provide a blueprint for designing autonomous small robots using phase-separated droplets, which change the mobility and molecular distribution within the droplet in reaction with the environment. It will also open unexplored areas of self-assembly mechanisms through phase separation under convections, such as intracellular phase separation.

Documenting Community Health Worker Compensation Schemes and Their Perceived Effectiveness in Seven sub-Saharan African Countries: A Qualitative Study.

Community health worker (CHW) incentives and remuneration are core issues affecting the performance of CHWs and health programs. There is limited documentation on the implementation details of CHW financial compensation schemes used in sub-Saharan African countries, including their mechanisms of delivery and effectiveness. We aimed to document CHW financial compensation schemes and understand CHW, government, and other stakeholder perceptions of their effectiveness. A total of 68 semistructured interviews were conducted with a range of purposefully selected key informants in 7 countries: Benin, Burkina Faso, Ghana, Malawi, Mali, Niger, and Zambia. Thematic analysis of coded interview data was conducted, and relevant country documentation was reviewed, including any documents referenced by key informants, to provide contextual background for qualitative interpretation. Key informants described compensation schemes as effective when payments are regular, distributions are consistent, and amounts are sufficient to support health worker performance and continuity of service delivery. CHW compensation schemes associated with an employed worker status and government payroll mechanisms were most often perceived as effective by stakeholders. Compensation schemes associated with a volunteer status were found to vary widely in their delivery mechanisms (e.g., cash or mobile phone distribution) and were perceived as less effective. Lessons learned in implementing CHW compensation schemes involved the need for government leadership, ministerial coordination, community engagement, partner harmonization, and realistic transitional financing plans. Policymakers should consider these findings in designing compensation schemes for CHWs engaged in routine, continuous health service delivery within the context of their country's health service delivery model. Systematic documentation of the tasks and time commitment of volunteer status CHWs could support more recognition of their health system contributions and better determination of commensurate compensation as recommended by the 2018 World Health Organization Guidelines on Health Policy and System Support to Optimize Community Health Worker Programs.

A mobility pilot development process experimented through a MaaS pilot in Budapest

Recently, several new concepts and innovative technologies have emerged to overcome the problems of urbanization, which can be hardly solved with using exclusively private vehicles or conventional public transport services. One of the new solutions is the Mobility-as-a-Service (MaaS) concept, a user-centric mobility distribution scheme, in which the user needs are satisfied via a single platform, and multiple transport options are offered by one MaaS operator (MO). In the last years, a couple of MaaS pilots were performed, but previous papers fail to focus on the pilot development and the proper description of the minimum viable product. A pilot of MaaS in Budapest has been developed by using the innovative Scrum methodology successfully involving six mobility service providers, such as public transport, shared mobility, and taxi, in the live demonstration. Current article provides detailed information about the pilot development including technical, legal, and business use cases for all service providers. The results of the recruitment and the characterization of the early-bird users are presented, too. The iterative pilot development process can be utilized by those MOs and governmental organizations that would like to initiate a new mobility project based on the MaaS concept.

Photoexcited Polaron Relaxation as a Structurally Sensitive Reporter of Charge Trapping in a Conducting Polymer

AbstractConjugated polymers (CPs) play a central role in electronic applications due to their easily tuned electronic and ionic conductivities via chemical or electrochemical doping. Although doping improves charge conduction by introducing high densities of carriers into the CP, the accompanying structural changes and their impact on carrier mobility remain elusive. Methods capable of probing carrier distributions and their dependence on polymer morphology are needed to better understand how to improve conductivity. Here, a transient absorption (TA) spectroscopy approach is demonstrated, capable of directly probing mobile and trapped carriers in doped CPs and that is also sensitive to polymer nanostructure by using a model polythiophene system with tuned crystallinity. Exciting polarons in the polymer films produces distinct photoinduced absorption signals in the near‐infrared spectrum that decay during the picosecond timescale in the form of biphasic, stretched exponential kinetics, which reflect a distribution of mobile (free) and trapped polarons. The kinetic analysis provides evidence for mobile polarons irrespective of polymer film crystallinity, whereas polarons located in impure amorphous phases with reduced chain ordering exist within a deeper distribution of trap states. Altogether, these observations suggest a stronger correlation of carrier trapping with local chain ordering (planarity or aggregation) rather than polymer crystallinity.

The interplay between soy proteins and dietary fiber in determining the structure and texture of high moisture extrudates

The (joint) contribution of soy proteins and dietary fibers (DFs) in determining the structure and texture of high moisture extrudates remains largely unclear. Blends of soy protein isolate (SPI) and a soy DF-enriched fraction (SDF) were prepared in different ratios, and their bulk rheology and water mobility distribution when hydrated to 60% moisture were related to the structure, texture, and protein extractability of high moisture extrudates prepared at the same moisture level. Increasing the DF proportion in hydrated SPI-SDF blends resulted in higher storage and loss moduli in linear region. In the non-linear region, however, higher DF levels resulted in more viscous behavior. The mobility of weakly interacting water protons decreased in samples with more DF. High moisture extrudates made from SPI had a layered microstructure consisting of V-shaped lamellae. Extrudates prepared from a blend containing 25% DF had more fibrous appearance with thin, branched protein-rich lamellae. Extrudates containing 52% DF exhibited a macrostructure without the presence of distinct layers or fibers and lacked a continuous protein network in their microstructure. The contribution of disulfide bonds to sustaining the protein network increased in extrudates containing more DF. Extrudates containing more DFs had lower cutting strengths and anisotropic indices. Strong negative correlations were found between the phase angle (obtained at 95 °C) in the non-linear region of the hydrated blends (indicating the relative importance of the viscous response) and the cutting strength of the extrudates in both longitudinal (R = −0.759) and perpendicular (R = −0.883) directions to the flow. In conclusion, the ratio of soy protein to DF had a significant impact on the characteristics of high moisture extrudates, which were associated with alterations in rheological properties, water mobility distribution and protein extractability.

Track Consensus-Based Labeled Multi-Target Tracking in Mobile Distributed Sensor Network

Track Consensus-Based Labeled Multi-Target Tracking in Mobile Distributed Sensor Network

Effects of Homologous instrument assisted mobilization (HIM) on ankle movement, gait-related muscle activation, and plantar pressure distribution in ankle dorsiflexion syndrome: A randomized single control trial.

While the limited ankle dorsiflexion syndrome (ADS) is common in neuro-musculoskeletal conditions, the instrument-assisted mobilization focused on the shortened gastro-soleus myofascial structure (IMI) rather than the homologous structure (both gastrosoleus and tibiliais anterior muscles, HIM). We aimed to compare the immediate therapeutic effects between IMH and IMI treatment groups on the ankle dorsiflexion angle, muscle activation and foot pressure distribution during dynamic gait in ADS. Neuromechanical tests including kinematics (ankle mobility), kinetics (center of pressure distribution), and electromyography were used to determine the immediate therapeutic effects between HIM and IMI treatment groups in 24 participants with ADS. The ankle joint angle analysis demonstrated a more improved active DF angle in the group who received HIM intervention when compared to the group who received IMI intervention. (11.26% and 3.58%, respectively) EMG analysis showed more decreased mean and peak TA activation amplitudes in the group who received HIM intervention (9.1% and 9%) when compared to the group who received IMI intervention (11.48% and 1.48%). Plantar pressure distribution analysis showed difference that the forefoot/area decreased in the group who received HIM intervention (8.1%), but rather increased in the group who received IMI intervention (14.3%). Our neuromechanical results demonstrated promising positive effects on ankle joint mobility, muscle activation and foot pressure distribution during gait in ADS.

Rancang Bangun Sistem Controlling Rpm Pada Main Engine Berbasis Arduino Uno Guna Mencegah Terjadinya Overspeed

As an important means of sea transportation for the distribution of goods and human mobility between islands, ships require a reliable prime mover to avoid wear or damage, especially when overspeeding occurs which can result in fire. Therefore, a prototype was created that uses an IR Obstacle sensor to monitor the RPM speed of the rotating engine. By using Arduino Uno as a processor, this prototype is able to display the RPM value on the LCD and provide a signal in the form of a green light if the speed is below 4000 Rpm, as well as a red light and buzzer sound if overspeed occurs above 4000 Rpm, followed by the engine turning off after 15 seconds. Testing shows that this prototype has a high level of accuracy, with a difference between 0.08% to 2.73% and an average difference of 1.003%.

Investigating advection–dispersion behavior for simulation of HTO and 238Pu transport in argillaceous shale with different varying degrees of weathering

Abstract Exploring the migration behavior of radioactive nuclides in the surrounding rock media of the disposal site is the basis for the safety evaluation of radioactive waste disposal sites. In this study, the column experiment was employed to evaluate the nuclide migration behavior in the surrounding rock medium of a near-surface disposal site in China and to investigate the advection–dispersion behavior of tritium (HTO) and plutonium-238 (238Pu) in highly weathered argillaceous shale with different degree of weathering. A reasonable numerical model was selected to fit the experimental breakthrough curves (BTCs) and obtain relevant migration parameters. The results showed that: (1) the breakthrough curves of HTO and 238Pu in fractured media with varying degrees of weathering exhibited clear “peak forward” and “tail dragging” phenomena; (2) the stream tube model can better fit the BTCs of the nuclides in the highly weathered fractures and obtain the average dispersion coefficient <D>, average distribution coefficient <K d>, and other parameters; (3) the two-region non-equilibrium model can better fit the BTCs of the nuclides in the penetrating fractures and weak weathering fractures and obtain the volumetric water content of the mobile liquid region (θ m), distribution coefficient (K d), and other parameters.

Using Capillary Electrophoresis to Investigate Protein Conformational and Compositional Heterogeneity.

Detailed insights into protein structure/function relationships require robust characterization methodologies. Free-solution capillary electrophoresis (CE) is a unique separation technique which is sensitive to the conformation and/or composition of proteins, and therefore provides information on the heterogeneity of these properties. Three unrelated, conformationally/compositionally-altered proteins were separated by CE. An electrophoretic mobility distribution was determined for each protein along with its conformational and/or compositional heterogeneity. The CE results were compared with molar mass distributions obtained from size-exclusion chromatography coupled to light scattering (SEC-MALS). Bovine serum albumin multimers and two monomeric species were separated, highlighting variations in conformational/compositional heterogeneity among the multimers. Analysis of yeast alcohol dehydrogenase resolved two monomeric conformers and various tetrameric species, illustrating the impact of zinc ion removal and disulfide bond reduction on the protein's heterogeneity. The apo (calcium-free) and holo forms of bovine α-lactalbumin were separated and differences in the species' heterogeneity were measured; by contrast, the SEC-MALS profiles were identical. Comparative analysis of these structurally unrelated proteins provided novel insights into the interplay between molar mass and conformational/compositional heterogeneity. Overall, this study expands the utility of CE by demonstrating its capacity to discern protein species and their heterogeneity, properties which are not readily accessible by other analytical techniques.

How big is a boulder? The importance of boulder definition choice in earth science research and river management

AbstractBoulders are globally widespread and influence processes across many landscapes including hillslopes, coasts, rivers and extra‐terrestrial settings. Boulders are described as particles, sufficiently large, that they have a disproportionate effect on the surrounding landscape. Moving beyond this conceptual definition, however, requires a somewhat arbitrary decision of how to define a minimum boulder size. The implications of boulder definition on study findings are rarely considered. We investigate the suitability of five boulder definitions, two based on fixed sizes: (1) 0.26 m and (2) 1 m, and three definitions which vary based on system characteristics: (3) grain mobility, (4) grain protrusion and (5) surface grain size distribution (> 84th percentile, D84). We consider the impact of definition on calculated boulder metrics, and, for the >1m and >D84 definitions, their association with channel and catchment characteristics across 20 boulder‐bed streams in northern Sweden. We also surveyed river managers responsible for restoring these rivers, to gain a practitioner insight on boulder size definition. We found that boulder definition matters; for metrics relating to the number or density of boulders, the >D84 and >1m size definitions were negatively correlated. Surveys indicated the importance of communicating boulder definition. We conclude that, whilst the best choice of boulder size definition will vary based on the questions of interest and techniques employed, evaluating the implications of the chosen boulder size definition and communicating the reasoning behind boulder definition choice is crucial.

Quantification of grain boundary mobilities in natural olivine by annealing experiments and full-field modelling

We investigate olivine grain boundary (GB) migration in natural peridotites experimentally annealed at high pressure and high temperature, and couple the experimental observations to full-field grain growth models to provide the distribution of GB mobilities in natural olivine polycrystals. A stack of four slices of natural mylonitic peridotite (Oman ophiolite) was annealed at 1473 K for 5 h under a confining pressure of 300 MPa of argon in a Paterson press. The three sintered interfaces of the stack are characterized using scanning electron microscopy and electron backscatter diffraction (EBSD) to extract a distribution of apparent (2D) GB displacements. Full-field simulations of numerically sintered interfaces are then used to infer the GB mean mobility and distribution in olivine polycrystal allowing forward modelling exercise to reproduce the experimental GB displacement distribution.This yields widely dispersed mobilities, which can be approximated by a log-normal distribution of 10−15.85±2.58m4.J−1.s−1. Both the average and the dispersion of GB mobilities can be explained by silicon grain boundary diffusion. Finally, we demonstrate that the high variability of GB mobilities in olivine implies a decrease of the mean growth rate with time. This elucidates the difficulties of extrapolating experimental grain growth rates to geological timescales and observed microstructures in peridotites.