Large Time Gap Research Articles

Predictive and Near-Optimal Sampling for View Materialization in Video Databases

Scalable video query optimization has re-emerged as an attractive research topic in recent years. The OTIF system, a video database with cutting-edge efficiency, has introduced a new paradigm of utilizing view materialization to facilitate online query processing. Specifically, it stores the results of multi-object tracking queries to answer common video queries with sub-second latency. However, the cost associated with view materialization in OTIF is prohibitively high for supporting large-scale video streams. In this paper, we study efficient MOT-based view materialization in video databases. We first conduct a theoretical analysis and establish two types of optimality measures that serve as lower bounds for video frame sampling. In order to minimize the number of processed video frames, we propose a novel predictive sampling framework, namely LEAP, exhibits near-optimal sampling performance. Its efficacy relies on a data-driven motion manager that enables accurate trajectory prediction, a compact object detection model via knowledge distillation, and a robust cross-frame associator to connect moving objects in two frames with a large time gap. Extensive experiments are conducted in 7 real datasets, with 7 baselines and a comprehensive query set, including selection, aggregation and top-k queries. The results show that with comparable query accuracy to OTIF, our LEAP can reduce the number of processed video frames by up to 9× and achieve 5× speedup in query processing time. Moreover, LEAP demonstrates impressive throughput when handling large-scale video streams, as it leverages a single NVIDIA RTX 3090ti GPU to support real-time MOT-based view materialization from 160 video streams simultaneously.

Childhood adversity is associated with anxiety and depression in older adults: A cumulative risk and latent class analysis

BackgroundThe long-lasting influence of childhood adversity on mental health is well documented; however empirical research examining how this association extends into older adults is limited. This study operationalises adversity using cumulative risk and latent class analysis (LCA) models to assess how adversity exposure and typologies may predict anxiety and depression in older adults. MethodsData came from the Personality and Total Health (PATH) Through Life Project (N = 2551, age 60–66). Participants retrospectively reported their childhood experiences of domestic adversity on a 17-item scale. Mental health was measured using four validated questionnaires of depression and anxiety. ResultsLinear and generalised additive models (GAM) indicated a dose-response relationship, where a greater number of cumulative adversities were associated with poorer scores on all four mental health measures. LCA identified a four-class solution; with high adversity and high parental dysfunction being associated with poorer mental health outcomes while moderate parental dysfunction and low adversity groups scored at healthy levels. Women reported higher overall anxiety than men, but no notable interactions between ACEs and gender were observed. Patterns revealed by LCA were similar to patterns shown by the cumulative risk model. LimitationsThere is a large time gap from childhood to assessment, making our study susceptible to recall bias. Also, our findings were based on cross-sectional data, limiting causal inferences. ConclusionChildhood adversity had independent and additive contributions to depression and anxiety in older adulthood, and both cumulative risk and person-centred approaches captured this relationship.

CASES OF SEXUAL VIOLENCE IN THE TEMPORARILY OCCUPIED TERRITORIES OF THE KYIV REGION IN 2022 – CRIMINAL CONSEQUENCES OF RUSSIAN AGGRESSION

An analysis of cases of sexual violence in the temporarily occupied territories of the Kyiv region in 2022 is given, an assessment of the criminal consequences of russian aggression is made, and the role of forensic medical examination in the investigation of such cases is determined.
 Aim of the work. An analysis of cases of sexual violence, including rape, that took place in the temporarily occupied territory of the Kyiv region in 2022 and the determination of the role of forensic medical examination during the investigation of these crimes.
 Materials and methods. The material of the research was 6 archival "Conclusions of expert research" of the Kyiv Regional Bureau of Forensic Medical Examination), which related to cases of sexual violence in the temporarily occupied territories of the Kyiv Region in 2022. For statistical processing of quantitative data, standard methods of variational statistics were used.
 Results. In all cases of sexual violence in the temporarily occupied territories of the Kyiv region during February-March 2022, the victims were women, including minors. They were subjected to sexual torture, including rape, with the use of physical violence and threats by Russian servicemen who, according to the victims, were in an intoxicated state, threatened with firearms, fired shots into the ceiling and floor of the living space, and forced the victim to perform actions contrary to her will. The forms of sexual violence were – verbal violation of a person's dignity, sexual intercourse in a natural (vaginal) and unnatural way (oral, anal) without the use of contraceptives. The violent sexual acts lasted about one hour. Immediately or in the shortest possible time after the indicated violent acts, the victims did not go to medical institutions for medical help and examination. After the deoccupation in June 2022, the victims turned to law enforcement agencies for facts of sexual violence and were examined in medical and diagnostic institutions of the city of Kyiv and in the Kyiv Regional Bureau of Forensic Medical Examination. During their examination, no visible injuries were found on the skin in the areas of the genitals and anus or on the mucous membranes that could be examined. At the time of the inspection, the victims did not make any complaints. In connection with the considerable time that passed from the events in February-March 2022 to the performance of forensic medical examinations in June 2022, the selection of the contents of the vagina, oral cavity and rectum for forensic immunological examination for the presence of spermatozoa – was inappropriate.
 Conclusions. In all cases, the victims were women, including minors, who were subjected to sexual torture, including rape with the use of physical violence and threats. These criminal actions correspond to both the Criminal Code of Ukraine and the "Convention against Torture and Other Cruel, Inhuman or Degrading Treatment and Punishment", the "Istanbul Convention", the "Istanbul Protocol" and the "Rome Statute". Since the facts of sexual violence against women by Russian servicemen during the occupation took place in March-April 2022, and the forensic medical examination of the victims - in June 2022, due to the large time gap between these events and the absence of physical manifestations of sexual torture, including rape, it was possible to establish only the fact of past sexual acts and the circumstances of their commission. Therefore, establishing the fact of rape belongs to law enforcement agencies. An important condition for the performance of a forensic medical examination in cases of rape as the basis of the evidence base in criminal proceedings is its timeliness, taking into account physical evidence and materials documenting bodily injuries.

Urdu Ghazal’s Initial and practiced forms in Baluchistan

In Baluchistan, the inception of Urdu poetry was delayed compared to other major literary centers of Urdu. There are several important reasons for this, which, along with the unfamiliarity of this remote region with Urdu as a language, the unavailability of chronological links from a research point of view bears specific importance. According to the known facts, the first voice of Urdu poetry was Mulla Muhammad Hassan Brahui; even after him, this region's poetic journey seems to have been divided into large time gaps. This paper presents an analytical study of Urdu Ghazal, which was created in Baluchistan until the establishment of Pakistan. These initial relics of Urdu Ghazal in Baluchistan are not more than practiced forms, so they mostly fail to present a high specimen of creativity. However, under the influence of this poetic capital, this tradition of Urdu Ghazal got strengthened here in Baluchistan, and afterward, through this route, high and unique features of Urdu Ghazal appeared here, which can be proudly compared to the overall Urdu Ghazal.

A coordination failure between EU climate policies exemplified by the North Sea energy island

ABSTRACT We highlight a coordination problem between the EU Emissions Trading System (ETS) and the EU's offshore renewable energy strategy. We exemplify this coordination failure by analyzing carbon leakage effects associated with Denmark's planned North Sea energy island. The Danish energy island project will not start production before 2033, implying a long interval between project announcement and production. Using a dynamic model of the EU ETS, we show that the large time gap between announcement and production likely results in a ‘Green Paradox’, where the energy island increases aggregate EU ETS emissions. The mechanism leading to the emission increase is complicated and works through the Market Stability Reserve (MSR). The estimated 2050 leakage rate is 145 percent in our main scenario and not below 100 percent in any alternative scenario. We discuss how to improve the climate benefits of the energy island or similar large-scale renewable energy projects. This includes possible revisions to the EU ETS and the role of Power-to-X technologies.

Impact of vehicle arrangement in mixed autonomy traffic on emissions

The environmental impact of the driving behaviour of autonomous vehicles (AVs) is not yet well-understood due to the scarcity of empirical mixed autonomy trajectory data. This study utilizes the Waymo Open Dataset to assess the environmental impact of mixed autonomy traffic considering different vehicle arrangements in a platoon: Human-driven Vehicle (HV) following AV, AV following HV, and HV following HV. Findings suggest that vehicle arrangements in a platoon have a significant impact on the AVs’ driving behavior and, consequently, on traffic emissions. The largest environmental benefits were found when an AV is in the lead position. However, when an AV is following an HV, the AVs were observed to drive more conservatively for safety purposes, with a larger time gap and deceleration, resulting in higher emissions compared to when an HV is following another HV. The results provide insights into the complexity of the environmental assessment of AVs in mixed autonomy traffic.

Intermittent social media usage: An empirical examination on the temporary discontinuance of blogging and its impact on subsequent user behavior

Social media usage is largely intermittent since users often temporarily pause the usage and resume after a while. However, the pattern of such Temporary Discontinuances (TD) has not been empirically quantified, and its impact on users’ subsequent behavior is still unclear. Tracing all blogs of more than 11 K users over an extended period of twelve years, the study adopts computational approaches to analyze the intermittent pattern of blogging activities. According to large time gaps between consecutive blogs, each user's lifecycle is divided into sessions of continued produsage and gap periods of TD. Results reveal that 57.37% of users experienced at least one TD, while 10.47% experienced more than five times of TD. Such TDs induce significant modifications in subsequent behavioral patterns. After the first TD, the readopted session lasts 46.46% shorter and contains 58.68% fewer blogs. TD also leads to modifications in the timing and content topics of blog posts. The longer the TD lasts, the more significant changes would be made in the readopted session. The empirical evidence provided in the study has the potential to enrich the theoretical understanding of post-adoption and discontinuance behavior, thereby offering novel insights into the practice of social media management.

Receptivity and Remating Propensity in Female Spodoptera litura (Fabricius) after Mating with an Irradiated Male or Its F1 Male Progeny.

The 'Inherited or F1 sterility technique' (IS), using sub-sterilized male moths, is a widely proposed pest management tool for Lepidoptera pests in general, and the tobacco cutworm Spodoptera litura (Fabr.) in particular. However, the multiple mating tendency of female moths and the ejaculate quality of male moths might influence the efficiency of this technique. Reduced ejaculate quality was observed in irradiated males, as evidenced by radiation's impact on certain bio-parameters, such as the weight of the spermatophores and their protein content, sperm count, the molecular expression of the sex peptide receptor (SPR) and egg fertility, with a greater impact in F1 male progeny. During the remating of females with untreated males, irrespective of the irradiation status of the first male, there was an increase in calling behavior, remating propensity and fertility in females, with a larger time gap between consecutive matings. The ability of F1 male progeny to check remating propensity in females 24 h after the initial mating was lower than that of unirradiated males. Partially sterile (130 Gy) males were as successful as unirradiated males in inducing the level of mating refractoriness in females. Decreased ejaculate quality in F1 male progeny could be associated with increased female receptivity during remating. Understanding the influence of male moth irradiation, insemination quality and post (initial)-mating intervals on the remating behavior of normal female moths and induced sterility might help in simulation modeling and optimizing IS insect programs.

High Minimum Inter-Execution Time Sigmoid Event-Triggered Control for Spacecraft Attitude Tracking With Actuator Saturation

This paper investigates the attitude tracking problem for spacecraft with limited communication, network congestion, unknown model parameters, actuator saturation, and external disturbances. To alleviate communication load, a novel sigmoid event-triggered mechanism is proposed with the special ability to guarantee a high minimum inter-execution time to avoid network congestion like package loss or time delay effectively. A neural network-based adaptive control algorithm is designed to deal with unknown model parameters. Besides, the problem of actuator saturation is tackled by introducing a dynamic loop gain function-based approach. System stability is proved by Lyapunov stability analysis and the high minimum inter-event time is substantiated by Zeno Behavior analysis with explanatory remarks. Numerical simulation results also show that a high minimum inter-event time and a high average inter-event time can be realized on the premise of high attitude tracking accuracy. Compared with all the previous studies, the ratio of the minimum inter-execution time to the average minimum inter-execution time has been improved by nearly 10 times with the proposed approach. Note to Practitioners—This paper was motivated by the problem of spacecraft attitude takeover control, but it also applies to other aperiodic discrete-time control systems. Existing event-triggered control methods have solved the problem of limited communication for attitude takeover control of spacecraft by reducing the number of times wireless communication is required. This paper proposes a new method for realizing quasi-periodic control with a large time gap between any two consistent control impulses using a hyperbolic tangent function or another sigmoid function in an event-triggered mechanism. The proposed sigmoid event-triggered mechanism (ETM) can magnify the event-triggered threshold dozens of times in a short time to avoid unnecessary frequent triggering without decreasing the precision of control. It’s feasible to employ the proposed sigmoid ETM to deal with limited communication and network congestion in other network control systems that are constructed with similar dynamic structures. Furthermore, it would be marvelous if we could transform this sigmoid ETM into a high-efficiency decision-making mechanism in some control systems without using a wireless network. Now we are studying how to realize orbital-attitude (maneuver) control with a relatively average time interval and fewer times of orbit transfer by using the proposed sigmoid ETM. Besides, to further improve the system performance, we are also seeking to further increase the ratio of the minimum inter-execution time to the average inter-execution time. For the purpose of a more even distribution of the triggering events on the time axis, we may modify the proposed sigmoid event-triggered method or associate it with other methods.

Evaluation of the success rate of various inpatient alcohol addiction treatment programs in the Czech Republic and their comparison

IntroductionHarmful alcohol use far exceeds other mental disorders in the proportion of patients who do not receive adequate treatment. Despite the long history of anti-alcohol treatment in Czech Republic, there is no published prospective study to this day, in which patients that underwent inpatient addiction treatment are compared to patients on the waiting list and only one prospective randomized study comparing two different medium-term inpatient programs was published.Almost all the studies published so far only bring results of particular hospitals. Differences in methodology, differences between cohorts of patients, absence of profiling and differences in therapeutic programs and historical changes makes comparison of results of those studies very difficult.ObjectivesThis work seeks to present and compare the data from studies that evaluate the success of medium-term inpatient treatment of alcohol dependent patients in the Czech Republic. Another aim was to identify problems that make such comparison difficult.MethodsBibliographia Medica Čechoslovaca and Pubmed was used to find studies published in professional medical journals since 1970, in which abstinence of patients who voluntarily completed medium-term inpatient treatment of alcohol dependence is evaluated.ResultsMedium-term inpatient treatment of alcohol addiction leads to one year abstinence in 34 to 76 % of patients. Such variance value is largely caused by different methodology of compared studies. In compared studies there are differences:1. in definition of abstinence2. if abstinence rate is assessed in all patients who have entered the treatment or only in those who have completed the treatment properly3. if abstinence rate is calculated using number of patients entering treatment or the number of patients who have been obtained by valid information (outpatient clinic, questionnaires)4. in the way the data was collected5. in the composition of patients6. in societal background, because there is large time gap present between compared studiesConclusionsThe comparison of individual studies presented many problems. Further steps should be taken to help compare treatment programs in the future, as they provide different therapeutic interventions in different intensity and length to different patients. Adequate patient profiling, detailed description of therapeutic interventions and identification of effective components of the therapeutic program is a way to support further research in this area, optimize existing programs and increase the overall efficiency of treatment.Disclosure of InterestNone Declared

Evaluating episodicity of high-temperature venting within seafloor hydrothermal vent fields

Hydrothermal episodicity refers to the cycle of cessation and reactivation of hydrothermal venting at the seafloor and is often considered a common characteristic of high-temperature seafloor hydrothermal systems. With few exceptions, evidence for episodicity at the vent field scale and at timescales of hydrothermal systems (1000s to 100,000s of years) is primarily derived from interpretation of the age distribution of rock samples collected from hydrothermal vent fields and dated using U-series disequilibrium techniques. Using this approach, significant age gaps between dated samples have been interpreted as hiatuses in the venting of fluids that form the deposits that accumulate at the vent fields. Here, we use Monte Carlo simulations to show that the maximum time gaps in the observed age distributions are similar to those predicted by modeling random sampling of a logarithmic age distribution. These simulation results indicate that large time gaps between dated samples do not indicate episodic venting, and/or the numbers of dated samples are not high enough to confidently distinguish between continuous and episodic venting. The lack of geochronological evidence for episodicity suggests that, although fluid temperature and composition within a vent field can vary over time, hydrothermal fluid circulation may be continuous over the lifespans of vent fields.

Detecting Isolated Stellar-mass Black Holes with the Roman Telescope

Isolated stellar-mass black holes (ISMBHs) are potentially discernible through microlensing observations, because they are expected to be long-duration microlensing events. In this work, we study the detection and characterization of ISMBHs using Roman observations. We simulate a large ensemble of such events, as they will be seen by Roman, and estimate the errors in the physical parameters of the lens objects, including their masses, distances, and proper motions, by calculating Fisher and covariance matrices. Since the ∼2.3 yr time gap between Roman’s first three observing seasons and its latter three seasons may lower the efficiency of its realization of microlensing events and characterization of ISMBHs, we additionally consider a scenario where we add a small number of additional observations—1 hr of observations, every 10 days, when the Bulge is observable during the large time gap—which is equivalent to a total of an additional day of observations with the Roman telescope. These extra observations increase Roman’s efficiency in terms of characterizing ISMBHs by ∼1%–2%, and, more importantly, they improve the robustness of the results, by avoiding possible degenerate solutions. By considering uniform and power-law mass functions (, α = 2, 1, 0.5) for ISMBHs in the range of [2, 50]M ⊙, we conclude that the Roman telescope will determine the physical parameters of the lenses (the mass, distance, and relative lens–source angular velocity) within <5% uncertainty, with efficiencies of 21% and 16%–18%, respectively. By considering these mass functions, we expect that during its mission the Roman telescope will detect and characterize 3–4, 15–17, and 22–24 ISMBHs through astrometric microlensing, with the relative errors for all physical parameters being less than 1%, 5%, and 10%, respectively. Microlensing events due to ISMBHs with masses ≃10–25M ⊙ that are located close to the observer, with D l ≲ 0.5D s, while the source is inside the Galactic disk, can be characterized with the fewest errors.

Memory-Anticipation Strategy to Compensate for Communication and Actuation Delays for Strings-Stable Platooning

Cooperative Adaptive Cruise Control (CACC) has the potential to significantly improve traffic throughput by reducing inter-vehicle following gap. However, communication and actuation delays in CACC systems are detrimental to string stability. A much larger time gap than the lump sum of the two delays is often required for CACC to guarantee string stability, which compromises their benefits on traffic throughput. It remains as a challenge to design string-stable CACC controllers that operate at small time gaps under delays. In this paper, we design a memory-anticipation CACC to explicitly handle communication and actuation delays to fulfill string stability specifications. The proposed controller employs a novel memory-anticipation spacing policy to address communication and actuation delays and is applicable to heterogeneous platoons. Unlike existing CACC controllers, our proposal utilizes past information of the preceding vehicle (i.e. the memory) instead of its current state/control information, which makes the controller robust to communication delay. Furthermore, a Smith predictor (i.e. the anticipation) is designed to compensate for the actuation delay. Both individual vehicle stability and string stability can be guaranteed with the minimum time gap as small as the summation of communication delay and actuation delay. Controller analysis and simulation verify the enhancement of the stability performance with respect to existing studies.

Vertical Integration of Teaching–Learning Methods for Clinical Tests of Hearing with the Physiology of Hearing: A Proposed Curriculum Improvisation Model for Undergraduate Medical Students

Introduction: Early clinical exposure (ECE) is a tried and tested attempt in teaching-learning methods (TLMs) to achieve the goal of integrating basic sciences with clinical methods and helps in creating competent clinicians for health-care delivery system. Vertical integration of basic sciences with clinical subjects, which improves problem-based learning, has met with considerable success. However, there is no ECE module for otology in the 1st-year physiology curriculum at present. Clinical skills training in otology is conventionally imparted only during the initial phase of final MBBS. Hence, there is a large time gap between learning the physiology of hearing and the actual implementation of that knowledge during learning clinical of assessment of hearing. The present study tested vertical integration of knowledge of physiology of hearing with clinical knowledge of assessment of hearing with the intention to achieve certain expected outcomes like better clinical skills in students, faculty development, overall improvement in the quality of management of patients with hearing loss, and the long-term and far-reaching positive impact on the community as a whole. Materials and Methods: 150 undergraduate 3rd year students of a medical college participated in the study. They were divided into two groups of 75 each. Pilot tested validated pretest questionnaires were offered to both the groups before intervening with the TLM. Group “A” was exposed to the vertical integration module, while Group “B” served as a control. Thereafter, Group “A” and “B” were further subdivided into five smaller groups each and a 60-min tutorial on tests of hearing was conducted for each of the small groups. Pilot tested validated posttest questionnaires were then offered to both the groups. Finally, feedback on the intervention was obtained through a pilot tested validated feedback form based on a five-point Likert scale from all participants. Results: The results showed that vertical integration promotes interaction among faculty from different departments and improves decision making abilities when designing and implementing appropriate TLM. It also improves learning outcomes among students by identifying the exact need for curriculum development and designing and testing an appropriate module for a particular task at hand. Conclusion: Competency-based medical education is the need of the hour and ECE is the most important step toward this. Appropriate vertical integration of various topics across all subjects is a long drawn out and time consuming task. However, by consistent inter-departmental faculty interaction and enthusiastic approach toward curriculum designing and development, the overall goal of training a medical graduate for transiting into an asset to the society seems achievable.

Comparing methods to estimate cloud cover over the Baikal Natural Territory in December 2020

The paper addresses the issue of how much cloud cover data obtained using satellite and model-interpolation techniques are suitable for monitoring the transparency of the atmosphere and determining conditions for airglow observations at a local geophysical observatory. For this purpose, we compared the temporal dynamics of cloud cover from ECMWF’s ERA5 reanalysis and NOAA satellites with the night atmosphere transparency according to a digital camera. We considered the dynamics of the addressed parameters at the Geophysical Observatory of the Institute of Solar-Terrestrial Physics, located in the Baikal Natural Territory near the village of Tory (Republic of Buryatia, Russia), during December 2020. The comparative analysis showed a generally good agreement between cloud cover data from ECMWF’s ERA5 climate reanalysis and those observed with the camera. Disadvantages are the lack of information on rapid variations in cloud cover in the reanalysis and positive and negative delays in the dynamics of cloud fields that last about two hours. Due to irregular satellite data, large time gaps between passes and difficulties in estimating cloud cover at night, we could not come to reliable conclusions concerning the applicability of satellite data.

Сопоставление методов определения облачного покрова над Байкальской природной территорией в декабре 2020 г.

The paper addresses the issue of how much cloud cover data obtained using satellite and model-interpolation techniques are suitable for monitoring the transparency of the atmosphere and determining conditions for airglow observations at a local geophysical observatory. For this purpose, we compared the temporal dynamics of cloud cover from ECMWF’s ERA5 reanalysis and NOAA satellites with the night atmosphere transparency according to a digital camera. We considered the dynamics of the addressed parameters at the Geophysical Observatory of the Institute of Solar-Terrestrial Physics, located in the Baikal Natural Territory near the village of Tory (Republic of Buryatia, Russia), during December 2020. The comparative analysis showed a generally good agreement between cloud cover data from ECMWF’s ERA5 climate reanalysis and those observed with the camera. Disadvantages are the lack of information on rapid variations in cloud cover in the reanalysis and positive and negative delays in the dynamics of cloud fields that last about two hours. Due to irregular satellite data, large time gaps between passes and difficulties in estimating cloud cover at night, we could not come to reliable conclusions concerning the applicability of satellite data.

Automated Cognitive Health Assessment Using Partially Complete Time Series Sensor Data.

Behavior and health are inextricably linked. As a result, continuous wearable sensor data offer the potential to predict clinical measures. However, interruptions in the data collection occur, which create a need for strategic data imputation. The objective of this work is to adapt a data generation algorithm to impute multivariate time series data. This will allow us to create digital behavior markers that can predict clinical health measures. We created a bidirectional time series generative adversarial network to impute missing sensor readings. Values are imputed based on relationships between multiple fields and multiple points in time, for single time points or larger time gaps. From the complete data, digital behavior markers are extracted and are mapped to predicted clinical measures. We validate our approach using continuous smartwatch data for n = 14 participants. When reconstructing omitted data, we observe an average normalized mean absolute error of 0.0197. We then create machine learning models to predict clinical measures from the reconstructed, complete data with correlations ranging from r = 0.1230 to r = 0.7623. This work indicates that wearable sensor data collected in the wild can be used to offer insights on a person's health in natural settings.

SDG Adherence of Social Performance Indicators Used by Brazilian Mining, and Oil and Gas Extraction Companies

This study aimed to examine whether the social performance indicators used by mining companies participating in the BM &amp;amp; FBOVESPA Corporate Sustainability Index (indice de sustentabilidade empresarial [ISE]) during 2005–2021 were aligned with United Nations’ Sustainable Development Goals (SDGs). Content analysis was conducted after collecting key information from voluntary sustainability reports presented by the companies. The results uncovered 423 social indicators and revealed repeated discontinuity and large time gaps of as many as 6 years in the disclosure of sustainability information. Among the SDGs investigated, the most discussed were (in order): SDGs 4, 3, 5, 1, 10, and 2. Thus, it is recommended that even though SDGs have been implemented since 2015, the desired social impact can be created only when companies in the mining and extraction sectors make a formal commitment to continuously disseminate sustainability reports and work equitably on SDG goals.

Investigating relationships among perceptions of yielding, safety, and comfort for pedestrians in unsignalized crosswalks

Interactions with other road users influence the perceived safety and comfort of pedestrians. Yet the relationships among perceptions of yielding, safety, and comfort are poorly understood. To enhance understanding of these key concepts, the objectives of this study are to determine how perception of pedestrian safety at unsignalized crosswalks differs from perception of comfort, and the relationship of each with perception of yielding. A generalized structural equations model is developed using data from an online survey in which 366 participants (i.e., “perceivers”) rated yielding, safety, and comfort for sample videos of pedestrian interactions with motor vehicles and bicycles. Results show that an individual’s perception of yielding plays a crucial role in mediating the effects of interaction attributes (e.g., vehicle speed, proximity) and perceiver attributes (e.g., travel habits) on their perceptions of pedestrian safety and comfort. For example, people who bicycle more frequently perceive pedestrians as more comfortable than people who walk more frequently, rooted in misalignment on what constitutes adequate yielding. Strategies to address pedestrian comfort can focus on a set of key yielding behaviors by drivers and cyclists – particularly allowing the pedestrian to cross first. Motor vehicle drivers must exhibit stronger yielding behavior (e.g., allow a larger time gap) than bicycles to achieve the same level of perceived pedestrian safety and comfort. Although perceptions of safety and comfort are strongly related and similarly impacted by yielding, researchers should be cautious about using the concepts interchangeably because they are differently impacted by attributes of the interaction and perceiver.

Laboratory testing of cross-country skis – Investigating tribometer precision on laboratory-grown dendritic snow

Small differences in ski-snow friction results in large time gaps, and glide testing is therefore an important part of racing. To test ski-snow friction without the influence of changing weather, snow conditions and skier position is therefore valuable. In this study, a full-scale ski-snow tribometer was developed and we investigated the degree of precision obtainable for different snow types, speeds, between separate ski tracks and snow surface preparations. The precision within new snow test tracks was 1.45%, and changing between parallel tracks added another 1.03% to the precision. Measurements across several dendritic snow testbeds were associated with a further 2.39% contribution to the precision. On aged snow, better precision was obtained within and between tracks on the same snow surface.