NGA-Subduction research program

This article summarizes the Next Generation Attenuation (NGA) Subduction (NGA-Sub) project, a major research program to develop a database and ground motion models (GMMs) for subduction regions. A comprehensive database of subduction earthquakes recorded worldwide was developed. The database includes a total of 214,020 individual records from 1,880 subduction events, which is by far the largest database of all the NGA programs. As part of the NGA-Sub program, four GMMs were developed. Three of them are global subduction GMMs with adjustment factors for up to seven worldwide regions: Alaska, Cascadia, Central America and Mexico, Japan, New Zealand, South America, and Taiwan. The fourth GMM is a new Japan-specific model. The GMMs provide median predictions, and the associated aleatory variability, of RotD50 horizontal components of peak ground acceleration, peak ground velocity, and 5%-damped pseudo-spectral acceleration (PSA) at oscillator periods ranging from 0.01 to 10 s. Three GMMs also quantified “within-model” epistemic uncertainty of the median prediction, which is important in regions with sparse ground motion data, such as Cascadia. In addition, a damping scaling model was developed to scale the predicted 5%-damped PSA of horizontal components to other damping ratios ranging from 0.5% to 30%. The NGA-Sub flatfile, which was used for the development of the NGA-Sub GMMs, and the NGA-Sub GMMs coded on various software platforms, have been posted for public use.

Psychometric characteristics of the Portuguese version of the Preschool Pediatric Symptom Checklist for children aged 18 to 60 months

Early detection of social-emotional and behavioral problems in children is important, because this anticipation allows for more effective intervention. Therefore, this quantitative, cross-sectional and instrumental study examined the factor structure, internal consistency, and various other psychometric properties of the Portuguese version of the Preschool Pediatric Symptom Checklist (PPSC). The participants were 398 Portuguese parents who completed the PPSC and a sociodemographic questionnaire. The PPSC, consisting of 18 items, measures the social-emotional statuses of children from the ages of 18 to 60 months. Three competing models (the unifactorial, 3-factorial and 4-factorial models) were tested as regards the PPSC’s factor structure using a confirmatory factor analysis. Our findings suggest that the original unifactorial scale of the PPSC is the most suitable in terms of the Portuguese version of this measure. The use of the PPSC in primary healthcare, its diagnostic accuracy, and children’s related social-emotional adjustment factors are then discussed.

Advances in pedestrian travel monitoring: Temporal patterns and spatial characteristics using pedestrian push-button data from Utah traffic signals

In this study, we advanced pedestrian travel monitoring using a novel data source: pedestrian push-button presses obtained from archived traffic signal controller logs at more than 1,500 signalized intersections in Utah over one year. The purposes of this study were to: (1) quantify pedestrian activity patterns; (2) create factor groups and expansion/adjustment factors from these temporal patterns; and (3) explore relationships between patterns and spatial characteristics. Using empirical clustering, we classified signals into five groups, based on normalized hourly/weekly counts (each hour’s proportion of weekly totals, or the inverse of the expansion factors), and three clusters with similar monthly adjustment factors. We also used multinomial logit models to identify spatial characteristics (land use, built environment, socio-economic characteristics, and climatic regions) associated with different temporal patterns. For example, we found that signals near schools were much more likely to have bimodal daily peak hours and lower pedestrian activity during out-of-school months. Despite these good results, our hourly/weekday patterns differed less than in past research, highlighting the limits of existing infrastructure for capturing all kinds of activity patterns. Nevertheless, we demonstrated that signals with push-button data are a useful supplement to existing permanent counters within a broader pedestrian traffic monitoring program.

GMPE-Consistent Hard-Rock Site Adjustment Factors for Western North America

Developing of site amplification factors for hard-rock conditions that are consistent with GMPE models at lower velocities.

Subnational Purchasing Power Parities as a Tool for the Interarea Comparison

The author describes the key characteristics of domestic and foreign experience in the development of conceptual and methodological foundations for the construction of subnational purchasing power parities. The relevance of the topic is explained, in particular, by the fact that subnational purchasing power parities are one of the key tools of the interarea comparison analysis. This causes the expanding attention paid by the national statistical ofces to its compilation and the development of the corresponding methodology. Thus, in July 2021, the World Bank as the Global ICP coordinator published two important guides presenting the international standards for producing purchasing power parities – for developing subnational PPPs and for integrating PPPs and CPI production activities.The international standards recommend considering the sum of expenditures on fnal consumption and gross fxed capital formation as the aggregated regional indicator in interarea PPP-based comparisons. A narrower indicator – household fnal consumption – can also be used depending on the purposes of further analysis; household budget survey data provide weights in comparing the consumer prices. Producing subnational PPPs is closely linked with assessing the spatial adjustment factors, which can provide an important tool in computing the national PPPs.Bearing in mind that producing subnational PPPs is a labor-intensive process, which includes all work stages (price data collection and validation, forming the weights system, computations, ensuring a balanced presentation of regions), the international standards suggest focusing on the annual frequency of works.Integrating the production of subnational PPPs with the CPI calculations system is one of the key factors for ensuring the efciency of the whole work.

Changes in global air pollutant emissions during the COVID-19 pandemic: a dataset for atmospheric modeling

In order to fight the spread of the global COVID-19 pandemic, most of the world's countries have taken control measures such as lockdowns during a few weeks to a few months. These lockdowns had significant impacts on economic and personal activities in many countries. Several studies using satellite and surface observations have reported important changes in the spatial and temporal distributions of atmospheric pollutants and greenhouse gases. Global and regional chemistry-transport model studies are being performed in order to analyze the impact of these lockdowns on the distribution of atmospheric compounds. These modeling studies aim at evaluating the impact of the regional lockdowns at the global scale. In order to provide input for the global and regional model simulations, a dataset providing adjustment factors (AFs) that can easily be applied to current global and regional emission inventories has been developed. This dataset provides, for the January–August 2020 period, gridded AFs at a 0.1×0.1 latitude–longitude degree resolution on a daily or monthly basis for the transportation (road, air and ship traffic), power generation, industry and residential sectors. The quantification of AFs is based on activity data collected from different databases and previously published studies. A range of AFs are provided at each grid point for model sensitivity studies. The emission AFs developed in this study are applied to the CAMS global inventory (CAMS-GLOB-ANT_v4.2_R1.1), and the changes in emissions of the main pollutants are discussed for different regions of the world and the first 6 months of 2020. Maximum decreases in the total emissions are found in February in eastern China, with an average reduction of 20 %–30 % in NOx, NMVOCs (non-methane volatile organic compounds) and SO2 relative to the reference emissions. In the other regions, the maximum changes occur in April, with average reductions of 20 %–30 % for NOx, NMVOCs and CO in Europe and North America and larger decreases (30 %–50 %) in South America. In India and African regions, NOx and NMVOC emissions are reduced on average by 15 %–30 %. For the other species, the maximum reductions are generally less than 15 %, except in South America, where large decreases in CO and BC (black carbon) are estimated. As discussed in the paper, reductions vary highly across regions and sectors due to the differences in the duration of the lockdowns before partial or complete recovery. The dataset providing a range of AFs (average and average ± standard deviation) is called CONFORM (COvid-19 adjustmeNt Factors fOR eMissions) (https://doi.org/10.25326/88; Doumbia et al., 2020). It is distributed by the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) database (https://eccad.aeris-data.fr/, last access: 23 August 2021).

Change in the self-reported health status of residents associated with the reduced aircraft noise around Tan Son Nhat Airport after the epidemic outbreak

The change in the self-reported health status of residents associated with the reduced aircraft noise around Tan Son Nhat airport (TSN) after the epidemic outbreak in early 2020 was investigated in three stages. Stage 1 is pre-outbreak when the airport was operating at its highest capacity. Phases 2 and 3 are three months and six months after the stop of international flight operation implemented in March 2020. Data on the residents' health status was obtained from face-to-face interviews. The questionnaire items were composed of Noise annoyance questions using the 11-point ICBEN scale, the Total Health Index, Health and lifestyle questionnaire, Depression Scale revised questionnaire, and questionnaires to identify insomnia, hypertension, and hearing loss. Other factors related to living conditions such as education, income, or housing were also collected as health adjustment factors. The noise levels of phases 2 and 3 were estimated by updating the noise contour map of phase 1 using the TSN airport's operation data in corresponding periods in 2020. This study provided evidence relating to variation of the residents' health status due to the noise situation change.

Water Quality Trading Framework with Uncertainty for River Systems Due to Climate and Population Characteristics

Climate change and population growth serve as fundamental problems in assessing potential impacts on future surface water quality. In addition to uncertainties in climate depicted in various representative concentration pathway (RCP) scenarios, futuristic population growth mimicking historical conditions is subject to uncertainties related to changing development patterns. The combination of climate change and population characteristics exacerbates concerns regarding the future water quality performance of river systems. Previous studies have established linkages among future climate, population impacts and watershed water quality performance. However, these linkages have not been specifically incorporated into water quality trading programs. Rather than temporally-variant adjustment factors, WQT programs use constant margins of safety for pollutant reduction credits resulting in trade ratios that do not explicitly account for futuristic climate and population uncertainties. Hence, this study proposes a conceptual framework for water quality trading establishing adjustment factors as margins of safety on trade ratios for pollutant reduction credits examining climate and population characteristics separately followed by evaluating them combined. This new framework is demonstrated using a programming script that calculates the margins of safety based on simulation results conducted through a water quality model of the Jordan River in Salt Lake City, UT, USA over a 3-year timeframe. With margins of safety over magnitudes of ±2 over the Jordan River simulations, this research introduces the framework as a foundation for developing adjustment factors for addressing climatic and population characteristics upon river systems.

Estimation of Optimal Speed Limits for Urban Roads Using Traffic Information Big Data

The use of an inconsistent speed limit determination method can cause low speed limit compliance. Therefore, we developed an objective methodology based on engineering judgment considering the traffic accident rate in road sections, the degree of roadside development, and the geometric characteristics of road sections in urban roads. The scope of this study is one-way roads with two or more lanes in cities, and appropriate sections were selected among all roads in Seoul. These roads have speed limits of the statutory maximum speed of 80 km/h or lower and are characterized by various speeds according to the function of the road, the roadside development, and traffic conditions. The optimal speed limits of urban roads were estimated by applying the characteristics of variables as adjustment factors based on the statutory maximum speed limit. As a result of investigating and testing various influence variables, the function of roads, the existence of median, the level of curbside parking, the number of roadside access points, and the number of traffic breaks were selected as optional variables that influence the operating speed. The speed limit of one-way roads with two or more lanes in Seoul was approximately 10 km/h lower than the current speed limit. The existing speed limits of the roads were applied uniformly considering only the functional road class. However, considering the road environment, the speed limit should be applied differently for each road. In the future, if the collection scope and real-time collection of road environment information can be determined, the GIS visualization of traffic safety information will be possible for all road sections and the safety of road users can be ensured.