Time Distance: A Novel Collision Prediction and Path Planning Method

Motion planning is an active field of research in robot navigation and autonomous driving. There are plenty of classical and heuristic motion planning methods applicable to mobile robots and ground vehicles. This paper is dedicated to introducing a novel method for collision prediction and path planning. The method is called Time Distance (TD), and its basis returns to the swept volume idea. However, there are considerable differences between the TD method and existing methods associated with the swept volume concept. In this method, time is obtained as a dependent variable in TD functions. TD functions are functions of location, velocity, and geometry of objects, determining the TD of objects with respect to any location. Known as a relative concept, TD is defined as the time interval that must be spent in order for an object to reach a certain location. It is firstly defined for the one-dimensional case and then generalized to 2D space. The collision prediction algorithm consists of obtaining the TD of different points of an object (the vehicle) with respect to all objects of the environment using an explicit function which is a function of TD functions. The path planning algorithm uses TD functions and two other functions called Z-Infinity and Route Function to create the collision-free path in a dynamic environment. Both the collision prediction and the path planning algorithms are evaluated in simulations. Comparisons indicate the capability of the method to generate length optimal paths as the most effective methods do

Towards a Decision-Making Algorithm for Automatic Lane Change Manoeuvre Considering Traffic Dynamics

This paper proposes a novel algorithm for decision-making on autonomous lane change manoeuvre in vehicles. The proposed approach defines a number of constraints, based on the vehicle’s dynamics and environmental conditions, which must be satisfied for a safe and comfortable lane change manoeuvre. Inclusion of the lateral position of other vehicles on the road and the tyre-road friction are the main advantages of the proposed algorithm. To develop the lane change manoeuvre decision-making algorithm, first, the equations for the lateral movement of the vehicle in terms of manoeuvre time are produced. Then, the critical manoeuvring time is calculated on the basis of the constraints. Finally, the decision is made on the feasibility of carrying out the manoeuvre by comparing the critical times. Numerous simulations, taking into account the tyre-road friction and vehicles’ inertia and velocity, are conducted to compute thecritical times and a model named TUG-LCA is presented based on the corresponding results

Estimation of adjacent building settlement during drilling of urban tunnels

Recent urbanization developments in big cities with limited available land for construction, have led the public transportation systems to go underground areas. The occurrences of unexpected damages due to wrong predictions on the behavior of the tunnel lining, the surrounding soil and the improper designing of the tunnel emphasizes the importance of the study and in addition the prediction of possible changes in form throughout the tunnel excavation. Studying the rate of a structure's settlement designed within the vicinity of these tunnels is therefore of great importance. In this paper, employing the Finite Element Method (FEM), optimizing settlement of the structure is considered throughout tunnel excavating. What have to be carefully considered are the horizontal distances between the tunnel and buildings with different stories, the diameter of the tunnel, and the relation between the settlements of buildings in any given direction. In addition, the vertical distance between tunnel and buildings is a crucial issue taken into account in this research. The result of this research can be useful to optimize the construction and implementation of underground structures

Student’s characteristics and fast food consumption

BACKGROUND: Fast food consumption is one of the risk factors for human health. The present study was conducted with the objective to investigate how students’ characteristics (attitude, control beliefs, and normative beliefs) motivate the consumption of fast food.METHODS: In this cross-sectional study, a total number of 401 students of Kurdistan University of Medical Sciences, Sanandaj, Iran, were randomly selected and studied in 2015. A questionnaire was administered to collect information about student’s demographic characteristics as well as their attitudes and beliefs towards using fast food. Correlation analysis and multivariate analysis of variance (MANOVA) followed by univariate ANOVA were used to interpret the results.RESULTS: The mean age of participants was 21.20 ± 2.80 years and 254 (67.20%) of them were female. Furthermore, 60.54% of the students were found with tendency to use fast food. The MANOVA analysis showed that the effect of gender on students’ characteristics was significant (P = 0.005), however the effect of grade was marginally insignificant (P = 0.053). Post-hoc univariate ANOVA showed that the gender was highly associated with control beliefs (P = 0.030) and normative beliefs (P = 0.004). No significant association was found between gender and student’s attitude (P = 0.610).CONCLUSION: A training program for medical students in Kurdistan University of Medical Sciences is recommended to encourage students to reduce the consumption of fast food

The relationship between religiosity with stress, anxiety, and depression among the students in Kurdistan University of Medical Sciences, Iran, 2017

BACKGROUND: Religion affects all aspects of the life. One of the most important aspects of human health is its mental health, and how it gets affected by stress, anxiety, and depression. The purpose of this study was to evaluate whether there was any relationship between religiosity with stress, anxiety, and depression among the students of Kurdistan University of Medical Sciences, Iran.METHODS: This cross-sectional study was conducted at Kurdistan University of Medical Sciences in 2017. The total number of 282 students were selected using a two-stage stratified sampling method to fulfill univariate religiosity questionnaire and Depression, Anxiety and Stress Scale-21 (DASS-21). All statistical analysis was performed using SPSS software.RESULTS: The mean age of participants was 22.34 ± 3.05 years. 70.9% of participants were women, and 92.2% were single. Out of four dimensions of religiosity, only ritual dimension was found to have a significant correlation with stress (P = 0.030). The correlation between other dimensions of religiosity (belief, emotional, and consequential (and aspects of mental health found to be not statistically significant (P > 0.050).CONCLUSION: Based on the findings of this study, religious activities can reduce the stress of individuals. Designing non-syllabus interventions is recommended in order to increase religious activities in order to improve students’ mental health

Time Distance: A Novel Collision Prediction and Path Planning Method

In this paper, a new fast algorithm for path planning and a collision prediction framework for two dimensional dynamically changing environments are introduced. The method is called Time Distance (TD) and benefits from the space-time space idea. First, the TD concept is defined as the time interval that must be spent in order for an object to reach another object or a location. Next, TD functions are derived as a function of location, velocity and geometry of objects. To construct the configuration-time space, TD functions in conjunction with another function named "Z-Infinity" are exploited. Finally, an explicit formula for creating the length optimal collision free path is presented. Length optimization in this formula is achieved using a function named "Route Function" which minimizes a cost function. Performance of the path planning algorithm is evaluated in simulations. Comparisons indicate that the algorithm is fast enough and capable to generate length optimal paths as the most effective methods do. Finally, as another usage of the TD functions, a collision prediction framework is presented. This framework consists of an explicit function which is a function of TD functions and calculates the TD of the vehicle with respect to all objects of the environment

A comparative study on the fatigue life of the vehicle body spot welds using different numerical techniques: Inertia relief and Modal dynamic analyses

Among different parts of a vehicle, the body is the main load-bearing component and as a result, its durability is critical. Fatigue analyses are typically divided into different categories, the quasi-static methods and the dynamic methods. The aim of this paper was to compare the inertia relief and modal dynamic approaches for their formulation, accuracy and computation time. The chosen case study is the fatigue life of the vehicle body. By utilizing multi-body dynamics model and driving the vehicle on different standardized roads and by different velocities, the force and moment time histories which act on the body were calculated and later used by the finite element model for the stress analysis. Then, by using the structural stress method, the fatigue life of the vehicle spot welds were calculated and the results were compared for both quasi-static and dynamic approaches. The findings reveal that the modal dynamic method is almost 37 times more time-consuming than the inertia relief approach, but if accuracy is desired, it can be up to 96% more accurate. Also as predicted, at low frequency loading (less than 10% of the first nonzero frequency of the structure), there is no difference between the results of both methods

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Dairy wastewater treatment plant in removal of organic pollution: a case study in Sanandaj, Iran

Background: Wastewater produced by a dairy in Sanandaj is a major source of environmental pollution threatening the city. The dairy uses activated sludge treatment to remove organic pollution from the wastewater. The present study evaluated the performance of this process and its compliance with national requirements for chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solids (TSS) remaining in the plant effluent. Methods: A total of 48 samples were obtained from the dairy inflow and outflow. The COD, BOD, and TSS were measured for each sample. The statistical sign test was used to assess the standards. Results: The results showed that the average BOD, COD and TSS in the input wastewater was 292.25, 422.92, and 198.33 mg/l, respectively. The ratio of BOD/COD was 0.69, which indicates the capacity of biological treatment was high. The BOD decreased to 64.22 mg/l (92% removal), COD to 33.74 mg/l (92% removal), and TSS to 43.11 mg/l (94% removal) in the effluent, indicating significant removal of water contaminants. The statistical sign test showed that TSS (P < 0.0001) and BOD (P = 0.031) were incompliance with national standards, but COD exceeded standard threshold (P = 0.076). Conclusion: Activated sludge treatment showed a good performance for TSS removal, but was not reliable for removal of BOD and COD pollutants

Evaluation of noise level at intensive care units in selected hospitals of Sanandaj

Background: One of the critical unit in each hospital is intensive care unit (ICU). The United States’ Environmental Protection Agency (EPA) recommends to control the noise level of this unit in order to not exceed 45 decibels (dBA) during the day and 35 dBA at night. In this study, our goal was to evaluate the noise level at adult and neonatal ICUs at some Sanandaj’s hospitals, Iran. Methods: This cross-sectional study was conducted from May 4th to June 4th 2012 in adult and neonatal intensive care units at three major hospitals in Sanandaj (Besat, Tohid and Tamin-Ejtemaei). In order to assess the noise level properly, measurements obtained during the days and nights. At a given day, a unit was selected randomly and measurement of sound levels obtained successively within two-hour periods. The noise levels were measured in decibels using a sound level meter (SLM). This process took four weeks to be completed (one week per unit). In the end of study, the total of 336 records of noise levels were obtained. Descriptive analysis as well as fitting a mixed effect models were used to interpret collected observations. All statistical analysis performed using R developed by R core team. Results: The preliminary analysis of observations showed that mean level of noise varied from 65 to 71 dBA among ICUs under study. Noise levels during the day were slightly higher than that of were observed during the night. Descriptive analysis of observations showed no major differences between the noise levels over the time and between the days/nights. Fitting a mixed-effects model showed significant differences of the noise levels between ICUs (P< 0.001). Conclusion: We found the noise levels were always above the EPA thresholds at all three hospitals both during the day and night. It is recommended to train hospital officials and staffs for keeping noise levels to an acceptable level