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The aim of this paper was to develop a mathematical model for the study of the kinematic parameters of an occupant and vehicle during a side impact crash. The proposed model has three bodies (the vehicle, the occupant torso and head) that are interconnected to each other by joints, springs and dampers. Also, the head-to-window contact force is taken into account in order to obtain accurate results for the occupant kinematic injury assessment. The model was designed using a CAD-CAE software, with a flexibility determined by a total of 63 input parameters and 10 selected output parameters. The model has shown positive results with a high degree of similarity to a crash test, overlapping with a margin of error within under 5 % for an impact simulation time of 300 ms. After validation, a number of parameters could be obtained from the model such as the linear and angular displacement of the torso, head and vehicle that can be used to study the side collision kinematics and dynamics. During the simulation, a displacement of 2 m for the vehicle was registered while a force of 3500 N was reached for the head-to-window contact, for a vehicle-to-vehicle initial collision velocity of 11.6 m/s.

In this paper we present an experimental study of SOI UTBB n-MOSFETs at cryogenic temperatures. The device employs fully silicided source/drain with dopant segregation formed by “Implantation Into Silicide” (IIS) process. The impact of the back-gate (Vback) on the device performance is systematically investigated. The results demonstrate that Vback is essential to tune the threshold voltage Vth. And optimization of Vback values can improve the subthreshold swing (SS), Drain-Induced Barrier Lowering (DIBL), transconductance Gm and mobility at cryogenic temperatures, providing a potential to fulfill the ultra-low power requirement for quantum computing application.

Phytosynthesis can certainly be considered next generation’s technology that enables the development of novel nanoparticles and nanomaterials with various applications in multidisciplinary scientific areas. Squash (Cucurbita maxima) is a fruit rich in beta-carotene, calcium, potassium and has numerous health benefits. This paper describes recent researches in the field of metallic nanoparticles, namely silver and gold, prepared via phytosynthesis from aqueous extracts of Waltham butternut squash. Silver and gold nanoparticles can be prepared using conventional routes that have numerous drawbacks. Phytosynthesis has multiple advantages: is cost effective, environmentally – friendly, doesn’t require high pressure and no hazardous chemicals are used. Aqueous extracts were prepared from different parts of Waltham butternut squash (e.g.: shell, core and seeds) and their phytochemical content was evaluated using standard qualitative and quantitative analyses. The metallic nanoparticles were phytosynthesized from the aqueous extracts and corresponding metallic salts using two different conditions: room temperature, no stirring, overnight and 500 C, under continuous stirring for 30 minutes. The phytosynthesized metallic nanoparticles were characterized by recording UV-Vis spectra at different time intervals in order to determine their stability in time. The characteristic absorptions maxima were recorded at 435 - 450 nm for silver nanoparticles and at 535 - 550 nm for gold nanoparticles. The antioxidant activity was recorded using DPPH (2,2 – diphenyl – 1 – picryl – hydrazyl – hydrate) assay and the calculated values were clearly higher for the phytosynthesized metallic nanoparticles compared to the aqueous extracts.

In this paper we present an experimental investigation on SOI UTBB n-MOSFETs at cryogenic temperatures. The device has a silicide source/drain with dopant segregation formed by "Implantation Into Silicide" (IIS) process. The controllability of the back-gate (V back ) on the device performance is characterized, showing that Vback is essential to tune the threshold voltage Vth and improve the subthreshold swing SS, Drain-Induced Barrier Lowering DIBL and mobility at cryogenic temperatures. The cryogenic effect on V th , SS and DIBL with different V back is also studied. Furthermore, using the V back and quantization effect at cryogenic temperature, we can optimize the SS to a lower value, providing a potential way to get ideal value of SS at cryogenic temperature.

Nowadays, the high quality of available building materials, powerful machinery and high precision construction techniques allow us to build bridges with very long spans at efficient costs. Depending on the site and the spans, the most common solutions for these types of structures are arch bridges, cable stayed bridges, suspension bridges and even variations among the three. Because of their size and the nature of the crossed obstacles, these types of structures can be very difficult to access outside the carriageways or the pavements and so, inspection maintenance works are very difficult and costly. One critical structural element which is common for all these bridges are the cables. They are out in the open, exposed to a wide variety of phenomena which can cause them damage. Although they perform exceptionally well under tensile forces in longitudinal directions, they are very weak and prone to take damage under transverse loads. For example, it has been observed, that long cable stays tend to vibrate uncontrollably. If left uncheck, these vibrations can resonate and cause damage to the protective sheath, anchorages and even the cables themselves, eventually leading to their collapse. In order to prevent this, engineers must take into account the various mechanisms that can cause vibrations, determine their effect on the stays, and find ways to mitigate them in order to reduce the amplitudes under acceptable levels. Cable vibration simulation using numerical models is very difficult to do, due to the high degree of uncertainty, large volume of processing to be done and lack of validation methods for the results. This paper presents a scaled model analysis of a cable stay in a wind tunnel where vibrations are measured under different wind speeds. Finite element models of the cable are then done, using the measurements to correct certain design parameters in order to improve the precision of the calculated results

Taking into consideration the importance of a bridge structure from economic and social point of view, the experimental testing of bridges before commissioning is mandatory for almost all the bridges. The analyzed bridge is a very important route for road vehicles and pedestrians to overpass the Danube – Black Sea Channel near the Agigea Port. The paper presents the dynamic tests of the bridge and the experimental results commented from two points of view. The results are related to the dynamic characteristics of the bridge and to the comfort of the pedestrians subjected to the vibrations induced by road traffic.

The past few years have witnessed major developments in nanotechnology with great potential in powering new therapeutic tools for cancer management. Our goal in this study was to develop a biocompatible nanoshuttle for the efficient delivery of 5FU in colorectal cancer patients. Silk fibroin/Poly(ethylene glycol) nanoparticles (SF/PEG NPs) were obtained and further loaded with 5FU. These nanoshuttles were characterized in terms of: morphological properties, size and size-distribution, drug uptake and release potential as well as in vitro cytotoxicity potential screening. The SF/PEG + 5FU NPs cytotoxicity was determined on HT-29 cells after determination of the lethal dose 50 and targeted the evaluation of the cells viability, proliferation potential and migration and invasion potential. The inflammatory profile of RAW 264.7 macrophage cells was also detrmined by flowcytometry. The basic cytotoxicity screening revealed that the pristine SF/PEG NPs displayed a good biocompatibility while the 5FU loaded NPs induced cytotoxic effects on HT-29 cells. More, the 5FU loaded SF/PEG NPs significantly reduced the migration and invasion processes as compared with the unloaded NPs. Lastly, we observed that the cytokines inflammatory profile was significantly altered after the treatment with the 5FU loaded SF/PEG NPs as compared with the unloaded nanoshuttles.

In this presentation transient absorption, steady-state and time-resolved fluorescence spectroscopy were used to investigate and characterize the photophysical properties of lanthanide complexes, as well as for applications by studying fluorescence quenching process. Also, we used different mechanisms such as dynamic quenching, ground-state complex formation, excited-state reactions, molecular rearrangements, and energy transfer.We chose to approach the characterization and investigation of lanthanide complexes for the theoretical information, and also sensors for applications resulting from this study.In order to better characterize the intermediate that appears at longer times, the metal complexes were studied by flash photolysis, with excitation at 355 nm. The lifetime, around 0.0001 s for each metal complexes was calculated by the analysis of the decays with and without oxygen. The measurements for quantum yield and lifetime were in powders, solution and film. The lifetime and quantum yield are dependent on the substitution on metal ions.Also, a new application of the compounds investigated for the detection of heavy metals from water was obtain. AcknowledgementsThanks CNCS-UEFISCDI, PN-III-P1-1.1-MC-2019-0285 for financial support.

In this presentation, absorption (transient absorption) and emission (steady state and time-resolved fluorescence) spectroscopy were used to study, investigate and characterize the mechanisms of fluorescence quenching and obtain new sensors with which to detect toxic environments: heavy metals from water. For this purpose, new compounds were synthesized in order to have a good fluorescence (high quantum yield), stability and selective sensibility. The study of fluorescence quenching by different metal ions, such as Ni2+, Cu2+, Co2+, Zn2+, Fe3+, Mn2+, Ca2+, Pb2+, Cr3+, Cd2+, Sr2+, and Mg2+, will be conducted in solution and film at different temperatures and variations in time to demonstrate that these samples have good stability and can be used as fluorescence sensors for the selective detection of metal ions. For fundamental study, the theory of dynamic quenching, theory of static quenching and combined dynamic and static quenching were used, and the constants of the process, lifetime in excited state, quantum yield and non-radiative and radiative rate constants were estimated. The lifetime, around 0.0001 s for each of the metal complexes, was calculated by the analysis of the decay with and without oxygen. Emission from singlet oxygen was observed at 1275 nm in all samples, and the lifetime and quantum yield are dependent on the substitution on metal ions. In addition, a new application of the compounds investigated for detection of toxic environments (heavy metals—Fe) was found: a sensor to detect Fe from water.

The increasing number of RF, microwave and analog-intensive-mixed-signal IC applications had led, over the two last decades, to the emergence of engineered substrate technologies that have helped to increase the adoption of the specialty foundry model for the semiconductor supply chain. In this paper we will review engineered substrate technologies with a special focus on 5G and its use case scenarios. We will also discuss how using 100% standard toolset and agile rampup techniques, engineered substrates could be manufactured to meet the stringent time-to-market and yield requirements of a semiconductor market in constant evolution

The objective of the paper was to assess the pedestrian’s head injury risk, in case of vehicle’s post-impact braking. In order to reach the established objective, two crash-tests were carried, using a crash-test dummy, equipped with tri-axial accelerometers, mounted in its head. In the first test, the vehicle was braked before the collision, while in the case of the second experiment, the braking occurred in the post-impact phase. Using the data collected from the crash-test, we were able to calculate HIC values in both cases, and assess the head injury risk. At the same time, we were able to determine the influence of the vehicle’s post-impact braking with respect to head injury severity risk.

Bicycle fatalities make up 8% of the total number of road accident fatalities in 2016 in the EU countries. In these countries, 2.015 people riding bicycles were killed in road accidents in 2016. During the night, the number of accidents involving cyclists is 26% higher than the number of accidents during the day. This work shows the influence of the reflective elements worn by cyclists on their visibility during the night. The tests were carried out on a public road, with cyclists wearing reflective vests of different colors (orange, yellow and white). The measurements were made using the low beam and the high beams for vehicles equipped with different types of bulbs.

As the development of the textile industry has progressed, intense concerns have been focusedon the contamination of the environment caused by dye pollutants [...]

The main objective of the paper was to analyze the degree of injury of the vehicle occupants by using virtual accident reconstruction software and calculating the HIC value. The injury level was calculated for the back-seat passengers in the case where the seatbelts were not used. One case study was analyzed where the drivers were racing and caused a collision with a turning vehicle at 130 km/h. The results expected are represented by the injury level probability and to observe if the survival limit was passed. The HIC value was correlated with the AIS injury scale and the acceleration level of the occupants head are compared to the tolerance limit of the human body. The novelty of the paper is that this is a new perspective to study real accidents and correlate them with the injury criterion (HIC) by the means of using virtual reconstruction software.

Recently, numerous studies have been carried out on various. [...]

Corrosion represents the transformation process of metallic surfaces, caused by the influence of the contact medium. Coins are not exempt from the undesired effect of corrosion. [...]

The purpose of this paper is to design a mechanism mounted on the occupant’s seat to control the recline of the backseat in the case of rear-end collisions to reduce the effects of whiplash upon the occupant’s neck and head using a virtual model of an occupant and seat. The design of the system is modeled in SolidWorks and simulated in this software by using the Adams physics model included in SolidWorks. The system will function similarly to a real sled; it is composed of a car’s seat, a multibody occupant and a surface along which the seat may slide. This system will be validated by comparing two real sled tests and a seat normally functioning. Once validated, the mechanism is enabled to make simulations which are conducted to analyze the differences in kinematics of the occupant’s neck and the various key parameters such as head accelerations, contact forces and T1 vertebrae acceleration. The multibody occupant is composed of multiple bodies inter-connected with joints and it will simulate a real occupant. As for the evaluation of injury potential for the neck, the neck injury criteria (NIC) are calculated for the comparisons of the two situations: when the backseat has normal rigidity and when the recline mechanism is activated. It was observed that, by using this recline mechanism, the key parameters were reduced. This paper presents the new developed mechanism with the obtained parameter reductions.

The goal of this paper is to determine how the geometry of the vehicle’s frontal profile is influencing the pedestrian’s head accelerations (linear and angular) in car-to-pedestrian accidents. In order to achieve this goal, a virtual multibody dummy of the pedestrian was developed and multiple simulations of accidents were performed using vehicles with different frontal profile geometry, from different classes. The type of accidents considered is characteristic for urban areas and occur at relatively low speed (around 30 km/h) when an adult pedestrian is struck from the rear and the head acceleration variation are the measurement of the accident severity. In the accident simulation 3D meshes were applied on the geometry of the vehicles, in order to define the contact surface with the virtual dummy, similar with real vehicles. The validation of the virtual pedestrian dummy was made by performing two crash-tests with a real dummy, using the same conditions as in the simulations. The measured accelerations in the tests were the linear and angular accelerations of the head during the impact, and these were compared with the ones from the simulations. After validating the virtual model of the car-to-pedestrian accident, we were able to perform multiple simulations with different vehicle shapes. These simulations are revealing how the geometric parameters of the vehicle’s frontal profile are influencing the head acceleration. This paper highlights the main geometric parameters of the frontal profile design that influence the head injury severity and the way that the vehicles can be improved by modifying these parameters. The paper presents an approach to determine the “friendliness” of the vehicle’s frontal profile in the car-to-pedestrian collision.

This paper describes a new generation of composite substrates dedicated to advanced surface acoustic wave (SAW) devices. For very long years, SAW applications (filtering, resonators, sensing) have been developed on single crystal materials. A competition was still existing with layered substrates using poly-crystals which were never able to overcome standard solutions. The Piezoelectric-On-Insulator (POI) structure which combines highly coupled single crystals with Silicon offers today unique properties to revitalize SAW industry and to give it a major push towards the modern telecommunication competition. This paper resumes the main steps that yields the technique to this edge and puts in perspective the potential of this breakthrough technology.

Carbonated hydroxyapatite derivatives (CHAp) and its metallic derivatives (Ag, Sr, Ba, K, Zn) have been prepared and characterized in this paper and their coating capacity on some model stone samples have been evaluated and discussed. These compounds were characterized by using several analytical tools, including X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), to determine the purity of the CHAp sample. The XRD and FTIR results confirmed the presence of AB-carbonated type CHAp. The thermal analysis (TGA) established two stages of weight loss that occured during the heating process: The first weight loss between 30&ndash, 225 &deg, C corresponding to the partial carbonate release from OH-channel and the second one between 226&ndash, 700 &deg, C, corresponding to some thermal reactions, possibly to the generation of calcium phosphate. The efficiency and suitability of these products on model stone samples were evaluated by monitoring the resistance to artificial weather (freeze&ndash, thaw), and pore structure changes (surface area, pore volume, pore diameter). Meanwhile, optical microscopy (OM) and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM&ndash, EDS) techniques showed the particles size and surface morphology of the samples, as well as information on its chemical composition. Also, the compressive strength of these new compounds as coatings revealed a homogeneity and strengthen of these model stone samples.

Sequential or monolithic 3D integration requires a combination of advanced manufacturing processes and highly reliable integration scheme at both device and substrate level. In order to achieve this, front-end layer transfer technology looks as key element of 3D integration flow. In this paper, we will bring an insight on technology challenges as well as solutions to enable sequential 3D device integration. We will also exhibit successful demonstration of low temperature device stacking using junctionless top devices.

This paper investigates advanced piezoelectric-on-insulator (POI) substrates elaborated using the Smart Cut™ technology to transfer a thin, high uniformity, single-crystal LiTaO 3 layer on top of a silicon handle wafer. These POI substrates enable the development of high quality surface acoustic wave (SAW) devices. Single-port test resonator have been built on such wafers, reaching Bode Q in excess of 1700 and coupling factors above 8 %, as the result of guided mode propagation. Resonance frequency dispersion was measured as low as 0.64 %. The thin layer stack also improves TCF down to 5.8 ppm/°C compared with conventional bulk LiTaO 3 technology and can be further reduced at desired frequencies by optimizing the multi-layer stack thicknesses.

The aim of the paper was to design, assemble and test a stand used to analyse various crash scenarios for a crash test dummy head. This stand can be used to test the head impact with different surfaces, with or without a helmet, on soft or hard surfaces at different impact angles. The idea was to design the stand in the CAD software SolidWorks because this particular software has the feature of dynamic simulation of assemblies known as Motion Analysis. The results show that designing the stand was a success and the simulations show a good behaviour of the assembly with direct results generated in term of acceleration and force values obtained from the drop test of the head on a surface. Also, the surface can be adjusted for different impact angles and with different contact surfaces properties to extend the usability of the assembly.

The objective of this paper was to determine the braking distance of a passenger vehicle when traveling at the speeds of 30, 50 and 70 km/h, on low friction surfaces (snow, deep snow) and also on asphalt. A number of tests were conducted on different surfaces. The vehicle was accelerated and then braked completely. Based on the braking distance values obtained by GPS, the adhesion coefficient was calculated for each surface for every velocity value tested.

This paper reports on recent advances in material innovation and substrate technologies enabling 5G. In particular, key requirements of 5G standards such as substrate linearity, power efficiency and RF/Analog performance are discussed. The characteristics of the initial substrate define the performance and architecture of the 5G devices and circuits. The results presented in this work summarize close cooperation between RF design, device technologies and advanced substrate manufacturing.

The aim of this paper was to analyse the influence of airbag deployment delay upon the head of the occupant in the case of frontal collision using simulations in PC Crash and MADYMO dummy as the occupant. The study will also take into account the pretension delay of the seat-belt which is activated along with the airbag. Frontal airbags on both the passenger and the driver were analysed including the occupant kinematics during the collision. Also, to validate the simulation, a comparison was done with a real crash test. We predict that by increasing the delay of deployment, the head acceleration will increase due to the fact the head travels close to the instrument panel/steering wheel, and the force of the airbag will generate a significant acceleration upon the head. To better assess the potential injury of the occupant, the head injury criteria (HIC) will be calculated and correlated with the Abbreviated injury scale (AIS) code.

Due to the increasing number of heavy trucks, the number of the overweight trucks have increased, and most of them, were recorded with axle overweight. This may lead to fines for the transportation companies, and to the road damage. One of the main reasons of axle over-weight is the COG displacement, which is influenced by several factors. The main objective of this paper is to determine the way that a suspension setting can influence the cargo load distribution inside a truck-semi-trailer assembly. In order to achieve the proposed objective, a calculation principle in regarding to the influence of the suspension setting upon the axle weight distribution for heavy trucks is presented. This calculation method was validated through experimental tests. The results indicates that the suspension setting plays a great role in the uniformly distribution of the cargo load, and using a wrong suspension setting, overloading on a certain axle may appear.

The responsive optical properties of some poly(siloxane–azomethine)s incorporating 1,8-dihydroxyanthraquinone units (PSA1 and PSA2) toward various metal ions (nickel (Ni2+), copper (Cu2+), silver, zinc, ferric, manganese, calcium (Ca2+), chromium, cadmium, barium, magnesium, lead, mercury, strontium, and cobalt) were investigated by steady-state and time-resolved fluorescence techniques. The fluorescence quenching has shown a significant deviation from the Stern–Volmer linearity due to the effect of combination of dynamic and static quenching for PSA1 in the presence of metal ions. Generally, the fluorescence decay is described by a two-exponential relation. The fluorescence of these PSAs was efficiently quenched by Cu2+ and Ni2+ ions, and these derivatives could be investigated as a promising system for the development of new sensors for the detection of Cu2+.

Absorption and fluorescence spectra of a polyquinoneimine, PQI, built on 1,4-dihydroxyanthraquinone and a siloxane diamine, 1,3-bis(amino-phenylene-ester-methylene)tetramethyldisiloxane, have been investigated in solvents of different polarities. The effect of solvents on the spectral properties was investigated using Lippert–Mataga and Bakhshiev polarity functions and Catalan’s multiple linear regression approach. Absorption and fluorescence spectra in studied solvents exhibit hypsochromic and bathochromic shifts, respectively. The polarity of the solvent was the main parameter which changes the spectral properties of PQI. Also, the binary mixtures of chloroform with methanol and dimethyl sulfoxide were used to analyze the intermolecular interactions and preferential solvation. The preferential solvation parameters (local mole fraction ( X 2 L ) , excess function (δs2) and preferential solvation constant (KPS)) were calculated from spectral data and discussed as a function of cosolvent content. The values of quantum yield, decreased linearly with increasing solvent polarity (for non-polar and polar solvents).

Considering on one hand the calculation model of the bridge, simplifying assumptions and design criteria and on the other hand the inherent differences between the project and final structure, the real structure behaviour under traffic loads can be different from that one considered in the design stage. Therefore the need of experimental tests before commissioning of bridges arises and this task is generally conditioned by complexity of the structure, the technologies used in construction and the requirements of the relevant stakeholders. The paper presents the test conditions for a reinforced concrete road bridge in Romania and the results obtained following the experimental tests. The experimentally determined dynamic characteristics of the bridge and the peek vertical accelerations are compared with those obtained by performing numerical analyses of the bridge. Due to the fact that the bridge is provided with walkways, it is appropriate to presume that the vibrations induced by road traffic will affect the pedestrians walking on the bridge. Same experimental data presented above can provide a view into how traffic induced vibrations can affect pedestrians on the bridge. For this reason, in the paper are presented the results in terms of human perception and the comparison between the resulting values and some generally accepted values

The main goal of this paper is to determine the differences regarding the head injury risk of a pedestrian in comparison with a cyclist which is not wearing a helmet. The secondary objective is to study the kinematics behavior for both pedestrian respectively the cyclist during the collision. In order to obtain accurate results, two crash-tests were performed using a dummy which had mounted a tri-axial accelerometer in the head. Using head acceleration values we were able to determine the head injury risk.

This paper studies the effect of a failed automotive front seat in the case of a rear-end collision and its effects on the occupants. Also, a comparison is made between a normal seat and a failed one. Two collision tests are conducted on the same conditions to analyze the similarities of the two. The occupants used are biofidelic crash test dummies. The occupant kinematics is analyzed and also the head acceleration is measured. The data is obtained from equipment mounted in the vehicles and occupants but also obtained from a high-speed video recording.