Numerical Simulation of Piezoelectric Sensor Used in a New Pedestrian Protection System

Volume 3 ◽  
2004 ◽  
Author(s):  
Renzo Capitani ◽  
Tommaso Iacomelli ◽  
Enrico Gobetto
Keyword(s):  
Experimental Analysis ◽  
Structural Characteristics ◽  
Sensor System ◽  
Crash Test ◽  
Electric Signal ◽  
Pedestrian Protection ◽  
Fem Model ◽  
Front End ◽  
Pedestrian Impact ◽  
The Impact

In recent years, pedestrians have been involved in many accidents. Statistics show that in Europe pedestrians are involved in 12% of the accidents and 20% of road users who lose their life in accidents are pedestrians. Authorities and automobile manufacturers are interested to reduce the physical damages of these users. The EU requires a very accurate design of new car front-end, because this is the first part involved in the car-to-pedestrian impact. Some EU organisations as EEVC (European Enhanced Vehicle-Safety Committee- Working Group 17) and ACEA (Association des Constructeurs Europeens d’Automobiles) have decided the directives on the design of the new car front-end. These documents settle on the experimental methods and the biomechanical parameters that have to be considered combining the front-end aggressiveness with the crash test dummies damages. Moreover, many car and system manufacturers are studying new pedestrian protection systems as the active hood that raises instantly when a pedestrian is hit: a sensor system placed in the vehicle’s front bumper sends a signal a two steel pistons below which lift the rear part of the hood making the pedestrian’s head hit a deformable and flexible surface instead of a hard and rigid one. These systems will help car manufacturers to meet the new EU test requirements that the European car manufacturers accepted in 2001 and that will become effective in July 2005. This paper describes an activity on car-to-pedestrian impact carried on by the Universita` degli Studi di Firenze in co-operation with Centro Ricerche FIAT. This activity concerns the study of legform FEM model for LS-Dyna software and the numeric simulation of a sensor system placed in the vehicle’s front bumper. The sensors are piezoelectric stripes stuck on the bumper according to opportune geometries. These sensors were characterised through experimental analysis changing deflection and impact speed; the relationship between the numeric parameters and the electric signal was determined working on easy tests. It was subsequently simulated the impact between the bumper and a legform FEM model developed by Universita` degli Studi di Firenze working on LS-Dyna software. The legform model respect the structural characteristics required by EEVC WG17 report. The legform model was validated by experimental analysis carried on at Centro Sicurezza FIAT AUTO. Thanks to simulations it has been possible to optimise the position of the sensors on the bumper and also to judge the minimum number of sensors, which can distinguish between the different impacts.

scholarly journals An Empirical Study Based on the Impact of Smart Sensor System on Rural Relative Poverty

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Tian Luan ◽  
Xiaoyan Liu
Keyword(s):  
Experimental Analysis ◽  
Rural Areas ◽  
Rural Poverty ◽  
Difficult Problem ◽  
Sensor System ◽  
Poor People ◽  
Smart Sensor ◽  
Related Factors ◽  
Relative Poverty ◽  
The Impact

Solving the problem of rural poverty is a difficult problem for the country to enter a well-off society in an all-round way. Therefore, this paper conducts an experimental analysis based on the impact of smart sensor systems on the relative poverty in rural areas. This article is aimed at studying the related factors of rural poverty and improving relative poverty in rural areas. In this regard, this article proposes an intelligent processing function based on smart sensors. Multiple sensors work together to process relatively complex things. Then, through the experimental analysis of GH efficiency, the data collected in the experimental area is used as the data. Combining the Lorentz curve and Gini coefficient analysis to determine the influencing factors of rural relative poverty. This article also selected 10 areas for experimentation. The experimental results show that the proportion of middle school education from 2014 to 2020 is between 24.3% and 34%, and the number of poor people has also declined, indicating that education level is a factor affecting rural poverty. Therefore, based on the intelligent sensor system, the factors of relative poverty in rural areas can be found, and related measures can be analyzed. By implementing the rural poverty alleviation strategy, the relative poverty situation in rural areas can be effectively improved.

scholarly journals REDESIGN OF OUTER HOOD PANEL OF ESEMKA R2 CAR TO IMPROVE PEDESTRIAN PROTECTION USING FINITE ELEMENT MODELING

2016 ◽  
Vol 17 (2) ◽  
Author(s):  
Binyamin Binyamin
Keyword(s):  
Finite Element ◽  
Impact Energy ◽  
Traffic Accidents ◽  
Head Impact ◽  
Pedestrian Protection ◽  
Element Analysis ◽  
Impact Performance ◽  
Head Injury Criterion ◽  
Pedestrian Impact ◽  
The Impact

Traffic accidents are terrible scourge that occur in many countries, specially for developing countries where transportation affairs like tangled yarn. Besides functioning as an engine compartment cover, the hood of modern compact SUV can also help to manage the impact energy of a pedestrian’s head in a vehicle-pedestrian impact. This paper presents outer hood design of Esemka R2 that has a potential to improve hood’s ability and also to absorb the impact energy of a pedestrian’s head. The developed method for the design of an outer hood configuration aims to provide a robust design and homogeneous of Head Injury Criterion (HIC) for impact position at WAD 1000 and three different thicknesses (1.25 mm, 1.35 mm & 1.50 mm) of outer hood panel of Esemka R2 compact SUV, taking into consideration the limited space available for deformation. The non-linear Finite Element Analysis (FEA) software (Explicit Dynamics) was used in this research to simulate the testing procedurs of head impact for child pedestrian. The results show that the average of comparison dimensional of outer hood panel of Esemka R2 was 4.89 mm. The minimum of deformation space meet the requirement for HIC value which required obtaining robust and homogeneous head impact performance. Outer hood thickness and materials were identified as the factors to influence the stress and HIC value of the hood. By comparing all outer hood panels, aluminium alloy as the best selected material which has the lowest value is 32.78% for the pedestrian protection.

scholarly journals A Study on Influence of Minivan Front-End Design and Impact Velocity on Pedestrian Thorax Kinematics and Injury Risk

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Fang Wang ◽  
Chao Yu ◽  
Guibing Li ◽  
Yong Han ◽  
Bingyu Wang ◽  
...  
Keyword(s):  
Impact Velocity ◽  
Injury Risk ◽  
Research Work ◽  
Thoracic Injury ◽  
Chinese Market ◽  
Computational Biomechanics ◽  
Front End ◽  
Vehicle Impact ◽  
Pedestrian Impact ◽  
The Impact

Thoracic injuries occur frequently in minivan-to-pedestrian impact accidents and can cause substantial fatalities. The present research work investigates the human thoracic responses and injury risks in minivan-to-pedestrian impacts, when changing the minivan front-end design and the impact velocity, by using computational biomechanics model. We employed three typical types of minivan model of different front-end designs that are quite popular in Chinese market and considered four impact velocities (20, 30, 40, and 50 km/h). The contact time of car to thorax region (CTCTR), thorax impact velocity, chest deformation, and thoracic injury risks were extracted for the investigation. The results indicate that the predicted pedestrian kinematics, injury responses, and thoracic injury risks are strongly affected by the variation of the minivan front-end design and impact velocity. The pedestrian thoracic injury risks increase with the increasing vehicle impact velocity. It is also revealed that the application of the extra front bumper is beneficial for reducing the thoracic injury risk, and a relatively flatter minivan front-end design gives rise to a higher thoracic injury risk. This study is expected to be served as theoretical references for pedestrian protection design of minivans.

scholarly journals Aberrant Bcl-x splicing in cancer: from molecular mechanism to therapeutic modulation

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Zhihui Dou ◽  
Dapeng Zhao ◽  
Xiaohua Chen ◽  
Caipeng Xu ◽  
Xiaodong Jin ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Human Cancer ◽  
Structural Characteristics ◽  
Therapy Resistance ◽  
Regulatory Elements ◽  
Aberrant Splicing ◽  
Clinical Role ◽  
Splicing Isoforms ◽  
The Impact ◽  
Splicing Patterns

AbstractBcl-x pre-mRNA splicing serves as a typical example to study the impact of alternative splicing in the modulation of cell death. Dysregulation of Bcl-x apoptotic isoforms caused by precarious equilibrium splicing is implicated in genesis and development of multiple human diseases, especially cancers. Exploring the mechanism of Bcl-x splicing and regulation has provided insight into the development of drugs that could contribute to sensitivity of cancer cells to death. On this basis, we review the multiple splicing patterns and structural characteristics of Bcl-x. Additionally, we outline the cis-regulatory elements, trans-acting factors as well as epigenetic modifications involved in the splicing regulation of Bcl-x. Furthermore, this review highlights aberrant splicing of Bcl-x involved in apoptosis evade, autophagy, metastasis, and therapy resistance of various cancer cells. Last, emphasis is given to the clinical role of targeting Bcl-x splicing correction in human cancer based on the splice-switching oligonucleotides, small molecular modulators and BH3 mimetics. Thus, it is highlighting significance of aberrant splicing isoforms of Bcl-x as targets for cancer therapy.

scholarly journals Simulation of Energy Absorption Performance of the Couplers in Urban Railway Vehicles during a Heavy Collision

Machines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 91
Author(s):  
Sunghyun Lim ◽  
Yong-hyeon Ji ◽  
Yeong-il Park
Keyword(s):  
Reaction Force ◽  
Crash Test ◽  
Railway Vehicle ◽  
Buffer System ◽  
Railway Vehicles ◽  
Hydraulic Shock Absorber ◽  
Coupling Buffer ◽  
Absorption Performance ◽  
Different Characteristics ◽  
The Impact

Railway vehicles are generally operated by connecting several vehicles in a row. Mechanisms connecting railway vehicles must also absorb front and rear shock loads that occur during a train’s operation. To minimize damage, rail car couplers are equipped with a buffer system that absorbs the impact of energy. It is difficult to perform a crash test and evaluate performance by applying a buffer to an actual railway vehicle. In this study, a simulation technique using a mathematical buffer model was introduced to overcome these difficulties. For this, a model of each element of the buffer was built based on the experimental data for each element of the coupling buffer system and a collision simulation program was developed. The buffering characteristics of a 10-car train colliding at 25 km/h were analyzed using a developed simulator. The results of the heavy collision simulation showed that the rubber buffer was directly connected to the hydraulic shock absorber in a solid contact state, and displacement of the hydraulic buffer hardly occurred despite the increase in reaction force due to the high impact speed. Since the impact force is concentrated on the vehicle to which the collision is applied, it may be appropriate to apply a deformation tube with different characteristics depending on the vehicle location.

scholarly journals Flexible Potentiometric Sensor System for Non-Invasive Determination of Antioxidant Activity of Human Skin: Application for Evaluating the Effectiveness of Phytocosmetic Products

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 76
Author(s):  
Aleksey V. Tarasov ◽  
Ekaterina I. Khamzina ◽  
Maria A. Bukharinova ◽  
Natalia Yu. Stozhko
Keyword(s):  
Antioxidant Activity ◽  
Human Skin ◽  
Skin Diseases ◽  
Silver Chloride ◽  
Potentiometric Sensor ◽  
Sensor System ◽  
Non Invasive ◽  
Pet Film ◽  
The Impact

In contemporary bioanalysis, monitoring the antioxidant activity (AOA) of the human skin is used to assess stresses, nutrition, cosmetics, and certain skin diseases. Non-invasive methods for skin AOA monitoring have certain advantages over invasive methods, namely cost-effectiveness, lower labor intensity, reduced risk of infection, and obtaining results in the real-time mode. This study presents a new flexible potentiometric sensor system (FPSS) for non-invasive determination of the human skin AOA, which is based on flexible film electrodes (FFEs) and membrane containing a mediator ([Fe(CN)6]3–/4–). Low-cost available materials and scalable technologies were used for FFEs manufacturing. The indicator FFE was fabricated based on polyethylene terephthalate (PET) film and carbon veil (CV) by single-sided hot lamination. The reference FFE was fabricated based on PET film and silver paint by using screen printing, which was followed by the electrodeposition of precipitate containing a mixture of silver chloride and silver ferricyanide (SCSF). The three-electrode configuration of the FPSS, including two indicator FFEs (CV/PET) and one reference FFE (SCSF/Ag/PET), has been successfully used for measuring the skin AOA and evaluating the impact of phytocosmetic products. FPSS provides reproducible (RSD ≤ 7%) and accurate (recovery of antioxidants is almost 100%) results, which allows forecasting its broad applicability in human skin AOA monitoring as well as for evaluating the effectiveness of topically and orally applied antioxidants.

scholarly journals Being a Gambler during the COVID-19 Pandemic: A Study with Italian Patients and the Effects of Reduced Exposition

2021 ◽  
Vol 18 (2) ◽  
pp. 424
Author(s):  
Maria Anna Donati ◽  
Silvia Cabrini ◽  
Daniela Capitanucci ◽  
Caterina Primi ◽  
Roberta Smaniotto ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Gambling Behavior ◽  
Online Gambling ◽  
Problem Gamblers ◽  
Electronic Gambling Machines ◽  
Electronic Gambling ◽  
Gambling Market ◽  
The Impact ◽  
Gambling Activities

The COVID-19 pandemic, with the consequent lockdown of about 3 months, can be viewed as an experimental model to observe the impact of the depletion of environmental factors that stimulate gambling, particularly electronic gambling machines (EGMs) that were set to zero. The effects of some structural characteristics of gambling activities that increase gambling behavior were studied among disordered gamblers in treatment in this unique scenario. In fact, studies investigating the effects of the lockdown on problem gamblers (PGs) under treatment are missing. The aims of this study were to analyze patients’ gambling behavior and craving during the lockdown and to conduct a comparison between gambling disorder (GD) symptoms at the beginning of the treatment and during lockdown. The study was conducted in Italy, the European country with the largest gambling market and the first to be affected by the virus. Data were collected through a semi-structured telephone interview conducted by healthcare professionals. Participants were 135 PGs under treatment (109 males, mean age = 50.07). Results showed that most PGs achieved a significant improvement in their quality of life, with less gambling behavior, GD symptoms, and lower craving. No shift toward online gambling and very limited shift towards other potential addictive and excessive behaviors occurred. The longer the treatment, the more monitoring is present and the better the results in terms of symptoms reduction. Individual and environmental characteristics during the lockdown favored the reduction in symptoms. Consideration for prevention and treatment are discussed.

A Study on Structural Characteristics of Biomass Briquette Boiler

2012 ◽  
Vol 197 ◽  
pp. 211-215 ◽  
Author(s):  
Ji Sheng Sheng ◽  
Biao Bing Wang ◽  
Wen Jian Li
Keyword(s):  
Thermal Efficiency ◽  
Experimental Analysis ◽  
Thermodynamic Calculation ◽  
Structural Characteristics

According to the experimental analysis on characteristics and combustion law of the biomass briquette, it designs the biomass briquette boiler based on the detailed thermodynamic calculation to promote the boiler’s combustion and thermal efficiency. The boiler adopts the chain grate stoker which strengthens the combustion intensity of the hearth. The longer the hearth becomes, the more intense the combustion of the biomass briquette is, so that the biomass briquette boiler of thermo performance design has helped realize such goals.

Numerical Simulation of the Impact between the Front-End-Coated Projectile and the Substrate Coated by Ceramic Film

2012 ◽  
Vol 226-228 ◽  
pp. 2198-2202
Author(s):  
Zhi Lin Wu ◽  
Xiao Mei Wang
Keyword(s):  
Normal Stress ◽  
Tangential Stress ◽  
Stress Wave ◽  
Acoustic Impedance ◽  
Axial Direction ◽  
Interfacial Stress ◽  
Ceramic Film ◽  
Front End ◽  
Ceramic Films ◽  
The Impact

The propagation of the stress wave in axial direction during the impact between the front-end-coated projectile and the substrate coated by ceramic films is described by the stress wave theorem. The impact process is numerically simulated by ANSYS/LS-DYNA, where the shell unit is used for precision. The effects of thickness of the front-end coating on the interfacial stress are discussed in detail. Dependence of different ceramic films are also considered. Simulation results show that interfacial normal stress is much greater than tangential stress. The interfacial normal stress is greatest when the thickness of the projectile coating is 0.2 mm. The interfacial tangential stress increases slightly as the thickness of coating increases. Similar stress history in the interface occurs when the acoustic impedance of the films are close. Greater acoustic impedance results in smaller stress.

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