Search

Skin burns are one of the most common injuries associated with increased morbidity and mortality, especially in the children and the elderlies. Severe burns, especially, result in a systemic immune and inflammatory response, which may reflect in multiple organ insufficiency, and a fast and effective local restorative process is essential for functionality recovering, as well as for interrupting the generalized systemic response. We have aimed here to assess the effect of different wound dressings in what it regards the morphology and clinical restoration after a skin burn. On a rat animal model, we have evaluated the macroscopic and histopathological features of controlled third degree skin burns in control animals versus treatments with local dressings of silver sulfadiazine (SDA) cream, simple gel (G), gel + silver nanoparticles (AgNPs) (G+NPS), gel + exosomes (G+EXO) and gel + AgNPs + exosomes (Gel+NPS+EXO), at 14 days and, respectively, 21 days after the lesion. Tissue fragments were harvested and processed for histopathology and immunohistochemistry. Immunofluorescence was utilized to evaluate the maturity of underlaying granulation tissue based on double stainings for smooth muscle actin (SMA) and cluster of differentiation 31 (CD31). Our study showed variability in what it regards the vessel density and immunoexpression of SMA between the treatments, and image analysis revealed that most SMA reduction and blood vessel density reduction in the maturing granulation tissue occurred for the G+NPS and G+NPS+EXO treatments. A complete re-epithelization was also observed for the G+NPS+EXO treatment. Overall, our results show that improved topic treatments promote faster re-epithelization and reparation of the dermis after skin burn lesions, providing thus an avenue for new treatments that aim both local recuperation and systemic infection prevention.

The objective of this paper is to investigate the fuel injection system in diesel engines by using inline pumps. In a diesel engines, the fuel injection pressure plays an important role in the combustion process in order to obtain high performance and low fuel consumption. The experiments in this paper are been performed on a 6 cylinder inline pump which is actioned by an electric motor with variable r.p.m.-s The quantity of the fuel injected by each injector is measured function of time and the speed of electric motor. The experiments show the degree of non-uniformity of the fuel delivered by the pump to injectors.

The current accelerated developments within the automotive sector have triggered a series of performance, comfort, safety and design-related issues. Hence, oftentimes manufacturers are challenged to combine various elements so as to achieve an attractive design, without diminishing the vehicle’s dynamic performance. In order to determine the vehicle dynamic performances we carried out an analysis by two methods. In the first part of the paper, we have used the analytical method to establish the dynamic performances of a vehicle. The second part of our study addresses another method to determine the star performances of the vehicle by means of computerized simulations. The first test aimed to determine vehicle starting performances for two vehicle models, with similar technical configuration, but with the same initial data. In the second test, we aimed at determining the start performance for the same car model, with the same initial data, but for different adhesion coefficients

Traumatic brain injury (TBI) represents a public healthcare problem and a major economic burden, all over the world. It is estimated that every year, on the globe, there occur about two million severe TBI and over 42 million mild TBI. The main causes of TBI in civil population are fallings, followed by car accidents. In the last decades, the accelerated development of car industry and the poor development of traffic infrastructure in low- and average-income countries led to an increasing number of brain injuries, this becoming a major problem for medical health systems. According to some studies, approximately 1.35 million people die every year because of car accidents. In the last four decades, these types of injuries started to be studied in order to understand the lesion mechanisms for developing new safety equipment that may be installed on vehicles. The device presented by us for causing a TBI in a lab rat (mechanical pendulum) allows the performance of several major types of TBI, according to the kinetic energy, exposure area, contact surface, etc. The impact energies obtained by the device we presented may vary on a large scale, from less than 1 J up to 10 J, according to its weight, launching angle and impact head shape, thus being obtained minor, moderate or severe TBI.

During the operation of internal combustion engines the air-fuel ratio (A/F) is an important parameter which affects fuel consumption and pollutant emissions. The automotive oxygen sensor (Lambda) measures the quantity of residual oxygen in the combustion gases. Sensor degradation in time due to the exposure to high temperatures causes a distortion in controlling the A/F with the increase in gas emissions. In this paper an experimental stand is designed to test oxygen sensor degradation in laboratory condition. Four oxygen sensors were tested function of temperature and time recording their variation in resistance and voltage. The results showed similar values in the curves for all sensors tested.

The current high-geared developments within the automotive sector have triggered a series of performance, comfort, safety and design-related issues. Hence, oftentimes manufacturers are challenged to combine various elements so as to achieve an attractive design, without diminishing the vehicle’s dynamic performance. Under the circumstances, the shape of the vehicle body becomes the key element that connects the design component with the performance requirement, since it directly influences the value of the resistance forces, and, respectively the air resistance. Aerodynamics is the branch of mechanical engineering that deals with the movement of gases (especially the air) and their effects on fluids. As far as the automotive sector is concerned, aerodynamics focuses mainly on the flow of the air currents over the vehicle body. When designing vehicle, the positive or negative displacement of the airflow is studied in aerodynamic tunnels. It is preferable for the negative displacement to push the vehicle as close to the ground as possible. In what follows we set out to study the influence of the drag coefficient and, implicitly, of the air resistance on vehicle performance. Hence, we will carry out comparative analysis of two vehicles with similar technical characteristics, but with different bodies, i.e. a hatchback and a sedan. The results obtained are then compared both by means of the analytical determination of the air resistance and via a simulation performed within the Virtual Crash software platform. The results recorded show that of the two vehicles, with the considered aerodynamic coefficients, hatchback type vehicle displays lower values in terms of air resistance.

The aim of the paper is to study the opportunities offered by an on-board data acquisition system (DAQ) in collecting, monitoring and controlling vehicle operating parameters. The testing system is able to obtain information concerning the energetic and dynamic parameters. It also has a built-in GPS system that allows the correlation between the information acquired with the route traveled. The data is collected from the vehicle in real-driving conditions and is processed with the aim of analyze it.

The purpose of this paper is to design and develop a formula student frame, according to the SAE regulation. The content of the paper contains a series of results obtained from frame loads at torsion and bending, using FEA (Finite Element Analysis). It should be mentioned that this design is a preliminary one, a prototype. After its construction, we will perform laboratory tests and begin the optimization processes. The ultimate goal is to get a frame that meets all the technical-economic requirements and to obtain competiton frame.

In the last 40 years CAD engineering has taken a considerable advantage in all domains. This has been imposed by the changes that have occurred in most of the environments with which engineering interacts in general, as well as by the technological advancement that has made the use of computers that have become increasingly efficient and are now indispensable to the technology [1]. The tendency of this period was consumer because prices fell as a consequence of globalization, the technique evolved, the standards became very rigorous, and the laws began to protect the consumer more.

The solid waste of Rapana thomasiana seashells both from domestic activities and natural waste on seashore can be used to obtain viable products for medical applications. However, conventional technologies applied for sintering the materials require massive energy consumption due to the resistance heating. Microwave heating represents an advanced technology for sintering, but the stability of the process, in terms of thermal runaway and microwave plasma arc discharge, jeopardizes the quality of the sintered products. This paper aims to present the results of research focused on viable heating technology and the mechanical properties of the final products. A comparative analysis, in terms of energy efficiency vs. mechanical properties, has been performed for three different heating technologies: direct microwave heating, hybrid microwave heating and resistance heating. The results obtained concluded that the hybrid microwave heating led to final products from Rapana thomasiana solid waste with similar mechanical properties compared with resistance heating. In terms of energy efficiency, the hybrid microwave heating was 20 times better than resistance heating.

The inland navigation sector makes a significant contribution to the growth of the global economy as well as to climate change due to pollutants emitted by diesel engines. NOx emissions are very high in port areas where, due to traffic, the ships run at idling regimes. Selective catalytic reduction (SCR) represents one of the most suitable technologies, in terms of cost effectiveness, but does not perform well if the temperature during vessel operation is lower than 180 °C. Microwave technology can support preheating of the ceramic core of SCR in order to increase the temperature towards the optimal interval for the best NOx reduction. Research has focused on coupling a magnetron head to a SCR device in order to evaluate to what extent the technology can meet the requirements of Stage V of the European Directive related to NOx emissions. Measurements of NOx emitted have been performed on engines with 603.5 kW nominal power and 1500 rpm that operate at a lower engine speed (700–1200 rpm) and output power (58–418 kW). The values recorded for emissions using microwave heating of ceramic core of SCR have decreased by 89% for a constant load of engine and idling engine speed.

Deaths caused by traumatic brain injury (TBI) increase in incidence every year worldwidely, mainly in developing countries. Thus, World Health Organization (WHO) estimates that in 2020, TBI will become the third main cause of death. In our study, we evaluated the deaths caused by TBI recorded within the Institute of Forensic Medicine of Craiova, Romania, between 2011 and 2017. Therefore, according to age, the cases were divided into two groups: people aged 0-18 years old (including 18 years old) and people aged over 18 years old (a total of 1005 cases, of which 971 were adults and 34 included in the age group 0-18 years old). In both groups, most patients were males from the rural area. In adults, falling was the main legal entity of the cases, followed by car accidents (which were the most common in children). In both groups, in car accidents, most of them were pedestrians and car occupants. Various aggressions (human, animal, self-injury) were found in 94 (9.68%) of the adult cases and in four (11.76%) cases of children. Another parameter under study was the blood alcohol concentration, being observed that most of the subjects with positive blood alcohol content died from car accidents. By evaluating the Glasgow Coma Scale (GCS) score as a prognostic factor, most of the subjects presented third and fourth degree coma at admission; still, 5.14% of the adult patients who deceased had GCS score 15 at admission, death occurring probably by developing some intracranial hematomas in time. Regarding the morphology of the lesions, most patients presented various forms of cranial fractures, 185 (19.05%) adults in association with extradural hemorrhages∕hematomas, but also there were four cases with extradural hematomas without any cranial fractures. In children, there was highlighted a single case of extradural hemorrhage under the fracture line. Seventy-eight percent of the adults and 44.12% of children presented subdural hematomas associated with other meningo-cerebral lesions. Also, 83.63% of the adults and 97% of children presented brain contusions. In both groups, brain laceration was observed in approximately 50% of the cases.

Temperature sensors are widely used in different industrial and scientific applications. These sensors commercially available in various type and configurations allow the enhancement of automotive systems. The manufactures need to improve and upgrade the technology by research activities regarding the accuracy of temperature measuring using sensors. In this paper will analyze the trends, applications and technologies in automotive temperature sensors. PTC/NTC thermistors are measured and characteristics curves are determined as expression of mathematical functions.

The objective of this study is to analyze and predict the flow through the intake manifold using a computational fluid dynamics program (CFD). The performance of internal combustion engine depends of the intake manifold and its components. Three model of the intake manifold flap was created and analyzed by using the commercially available ANSYS software. The volumetric efficiency which affects the engine power and torque is affected by the flow of air in the intake manifold. These paper reviews the work realized by various researchers in the field of variable intake manifold. The CFD plots offers valuable information’s of the flow field and tension distribution in the various part of intake manifold flap mechanism. The results show that the CFD model can be used as a tool for improve and optimize various part of the intake manifold flap.

The ever-growing demand for transportation and the need to carry both people and goods has led to increased congestions of road traffic networks. Subsequently, the main negative effect is the multiplication of serious road accidents. Of the total number of serious road accidents, a significant increase has been registered among cyclists, with 13.9% in 2014 of total vehicles involved in traffic accidents, compared to 6.6% in 2010. The present paper underpins a close analysis of the kinematic and dynamic parameters in the event of a vehicle - bicycle – cyclist assembly – collision type. To study the vehicle-bicycle-collision type, we carried out a comparative analysis with regard to the distance the cyclist is thrown away following the collision, the speed variation of the vehicle and of the bicycle, and the speed variation in the cyclist’s head area, as well as the variation of the acceleration recorded on the vehicle, the bicycle and the cyclist’s head area. Hence, we modelled and simulated the vehicle – bicycle collision for two distinct instances, i.e. a frontal vehicle – rear bicycle collision and a frontal vehicle - frontal bicycle collision.

The objective of this study is to analyze the flow filed in the intake manifold using Computational Fluid Dynamics (CFD). The main function of the intake manifold flap is to regulate the air flow and to uniformly distribute in the cylinders. If the air is distributed uneven to the engine the volumetric efficiency, power and fuel consumption is reduced. The finite element method can be used to optimize the throttle flap. The results in the simulation offer valuable information’s of the flow field in the throttle assembly. The results show that the CFD model can be used as a tool for improve and optimize various part of the intake manifold flap.

In the automotive field, the application of Lean Manufacturing principles has become a common practice in recent decades. One of the basic methodologies of Lean philosophy is the Total Productive Maintenance (TPM). The TPM includes a number of methods initially designed to ensure the continuous operation of the machines involved in the production process so that production is never interrupted. In this paper some of the most important steps in quality improvement by implementation of TPM in an automotive company are presented. It is described the monthly implementation extent of TPM indicators starting from 2014 until now, especially on the production lines of the factory. Finally, the major benefits of TPM principles implementation in the company are highlighted.

Smarty city is a current topic, growing very fast in the last years. This concept is linked as a winning strategy to solve some major problems of big cities, like pollution, traffic jams, energy consumption, etc. Smart city is the next level, a more complex concept of the much restrictive green city, being an extension of this one, involving a better urban zone, a smaller environmental footprint, a higher penetration of ICT in the city life. A very important component of a smart city is the urban mobility, a smart mobility in a smart city. The aim of the paper is the presentation of the first step in this direction, because a smart mobility involve a smart signalization first. To reduce the traffic jam in an cross junction, an adaptive signal master plan of the intersection are used, with the help of a dedicated software.

In this paper an experimental setup was designed and realized in laboratory to test and measure the engine mass air flow sensor used in engine applications. The MAF sensor is installed usually between air filter and the intake manifold of the engine and measure the amount of air entering the engine or the air flow. A contaminated and failed mass air flow sensor shows a lower or higher air flow readings causing various drivability problems. The stand simulates the condition of function of MAF sensor by various air flows and temperature recording the flow by a pitot tube.

The purpose of the paper is to build a 3D frame with of a kart with the opportunity to make it physically. The starting point, consists in analyzing an already existing kart chassis so that the key points and elements can be found in the final model. The methods in which this can be done are multiple, but the most efficient in terms of time, is the 3D scanning of the chassis and passing through the re-verse engineering methods, then following the 3D reconstruction with some specialized software.

The paper aims to determine the solicitation in the rear axle support of a karting type structure, which are used in karting competitions. The analysis was made analytically and with the help of specialized software, with a good approximation between the two methods of analysis. These methods can also be extended to compute others solicitations in areas considered dangerous for the karting type structure.

One of the consequences of the ever-increasing demand of transport needs is reflected in traffic accident statistics and the recorded number of road accident victims. In case of motorcycle accidents, the highest and most serious injuries are caused following a car crash.

The second part of the paper aims to resolve the reconstruction process of the chassis. The method by which the 3D scanned chassis will be reconstructed is through the utilization of the reverse engineering methods with the help of specialized software. The base point of the reverse engineering is to utilize a discretized 3D model, which in this case was created by 3D scanning. Typically, reverse engineering it is used to analyzing in detail the model, in order to create a new device or similar system, which does not copy anything from the original one.

For this study with high originality, some aspects about the sintering behaviour of Titanium based alloy used for automotive components are presented. This paper presents the experimental results concerning the processing of Ti based alloy by Powder Metallurgy (PM) technology. The initial powder mixture consists in TiH2 micrometric powder particles that have been combined with some metallic powders for improving the final mechanic-chemicals and functional properties for using in the automotive industry. The classical PM route have been applied for obtaining a low-cost Ti- alloy.As a result it was compulsory to study the parameters that influence the densification process and the sintered properties, depending on the sintering temperature. The experimental test results were processed using the STATISTICA program. Therefore the influence of these sintering temperatures on the height and diameter shrinkages, density and hardness for the alloys based on Ti micrometric powders has been studied.

The internal combustion engine that equips a vehicle is a complex assembly of mechanical parts and electronics that controls almost every system. The electronic part of the vehicle gives the opportunity to observe and control what happens with the engine during function. The present paper follows the evolution of the pollutant emissions in relation with some transitory regimes of the car.

The author’s present concerns about the study opportunities offered by the control unit (which allow experimental programming) related to viewing, adjusting and recording certain engine operating parameters. For a dedicated power supply solution (in which we find an own admission variant of route) functional enhancements the related to the settings type of injection, number of injections, injection time and air mixture – fuel, are proposed. Performance evaluation, approached in a sequence type identification system was done using a testing methodology specific to the chassis dynamometer bench to highlight the targeted optimizations.

The paper presents a possible practical application based on two 6R overconstrained mechanism, more precisely 6R Wohlhart overconstrained mechanism. Two of these mechanisms are put in a mirror position, in order to obtain a car jack. The mechanisms are disposed in other position than the original one, three non-adjacent joints being constrained to remain in a fixed plane.