bluuebunny/crossref_metadata_2025 huggingface dataset:
A semitransparent particulate photoanode composed of SrTiO3 powder anchored on titania nanosheets
Authors: Kageshima Yosuke , Momose Haruka , Takagi Fumiaki , Fujisawa Sora , Yamada Tetsuya , Teshima Katsuya , Domen Kazunari , Nishikiori Hiromasa
Published: August 2021

A particulate semitransparent photoanode composed of SrTiO3 powder anchored on a titania nanosheets layer is developed. A tandem-type photoelectrochemical cell employing particulate photoanode and photocathode performed overall water splitting.
Fingering instability in spreading epithelial monolayers: roles of cell polarisation, substrate friction and contractile stresses
Authors: Trenado Carolina , Bonilla Luis L. , Martínez-Calvo Alejandro
Published: August 2021

Numerical simulations and linear stability analyses of expanding cellular monolayers suggest cell–substrate friction is responsible for fingers at the edge. A critical contractile stress characterises wetting-dewetting; dewetting inhibits fingering.
Soft nanoconfinement of ionic liquids in lyotropic liquid crystals
Authors: Bandegi Alireza , Marquez Garcia Maria , Bañuelos Jose L. , Firestone Millicent A. , Foudazi Reza
Published: August 2021

Nanoconfinement of ionic liquids (ILs) influences their physicochemical properties.
Active strain engineering of soft plasmene nanosheets by thermoresponsive hydrogels
Authors: Fu Runfang , Liu Siyuan , Shi Qianqian , Lu Yan , Yong Zijun , Cheng Wenlong
Published: August 2021

Integration of soft plasmene nanosheets with thermoresponsive hydrogel enables omnidirectional strain engineering that leads to the dynamic manipulation of their plasmonic property by programming temperature.
Local finite element approximation of Sobolev differential forms
Authors: Gawlik Evan , Holst Michael J. , Licht Martin W.
Published: August 2021

We address fundamental aspects in the approximation theory of vector-valued finite element methods, using finite element exterior calculus as a unifying framework. We generalize the Clément interpolant and the Scott-Zhang interpolant to finite element differential forms, and we derive a broken Bramble-Hilbert lemma. Our interpolants require only minimal smoothness assumptions and respect partial boundary conditions. This permits us to state local error estimates in terms of the mesh size. Our theoretical results apply to curl-conforming and divergence-conforming finite element methods over simplicial triangulations.
Computation of optimal transport with finite volumes
Authors: Natale Andrea , Todeschi Gabriele
Published: August 2021

We construct Two-Point Flux Approximation (TPFA) finite volume schemes to solve the quadratic optimal transport problem in its dynamic form, namely the problem originally introduced by Benamou and Brenier. We show numerically that these type of discretizations are prone to form instabilities in their more natural implementation, and we propose a variation based on nested meshes in order to overcome these issues. Despite the lack of strict convexity of the problem, we also derive quantitative estimates on the convergence of the method, at least for the discrete potential and the discrete cost. Finally, we introduce a strategy based on the barrier method to solve the discrete optimization problem.
Study on the influence of technological parameters on 3D printing with sla technology
Authors: Komjaty Andrei , Wisznovszky (Muncut) Elena Stela , Culda Lavinia Ioana
Published: August 2021

The influence of the technological parameters of the printing through the SLA (Stereolithography) technology is presented. This printing technology is based on the use of a photosensitive resin, which polymerizes in contact with UV rays with a wavelength of 405nm. An Anycubic Photon Mono printer is used, on which parts are printed, in which the dimensional accuracy and the condition of the resulting surfaces will be analyzed. It will study the influence of the polymerization time of the resin (5s - 10s), of the advance step between the successively deposited layers (0.05mm - 0.2mm), as well as the influence of the placement positioning of the reference mark for printing. A Black basic type, monomer with photo-initiator photosensitive resin will be used made by Anycubic,. A Sony alpha 37 DSLR camera with Sony SAL-100M28 100mm F / 2.8 AF Macro lens will be used to capture images for the resulting surfaces.
The influence of the cycloid disc bearing type on the cycloidal speed reducer efficiency
Authors: Vasic Milan , Blagojevic Mirko , Matejic Miloš , Cofaru Ileana Ioana
Published: August 2021

The robotics industry has experienced a rapid expansion in the last decade. As a result, the market of speed reducers with high gear ratios, high precision and a compact design is growing rapidly. In addition to these characteristics, it is very important for gear trains to have high efficiency. Because of their compact design, cycloidal speed reducers are not exposed to axial forces, which is their important characteristic. This means that radial bearings can be used in their supports. The bearing type has significant effects not only on the design and dimensions of the cycloid speed reducer but also on its efficiency. In this paper, an analysis of power losses for different types of rolling bearings of a cycloid disc has been performed. At the end of the paper, concrete conclusions are presented as well as directions for future research.
Modular milling cutter with inner-cooling network
Authors: Dragoi Mircea-Viorel , Rosca Dorin Mircea , Folea Milena Flavia , Oancea Gheorghe
Published: August 2021

The big sized milling cutters are expensive tools and are not appropriate for small batches production. Making these tools more versatile, able to fit to different kinds of processes and shapes of the parts to be machined is a must. As well, cooling the cutting area is very important. The existing end-mill cutters are designed to feed internally with coolant only the teeth on the front side. The paper presents a concept of a modular tool, made of elementary disk cutters, able to be reconfigured to get different shapes and sizes. The main element of novelty the paper claims is the inner cooling system of the complex tool. The special design of the elementary milling cutters and of the shaft they are mounted on make the tool able to lead jets of coolant to every insert, no matter where they are placed, on the cylindrical or on the front side of the milling cutter. A network of channels drilled in the shaft and in the body of elementary milling cutters make this possible. The capability to splash with coolant under high pressure all the cutting edges do not depend on the number of teeth of the tool. Being delivered from inside the cutting tool, the coolant splashes directly on the contact surface between the inserts and workpiece, which makes cooling more efficient.
Research regarding assembly flow optimization of wiring harness in automotive industry
Authors: Stefan (Iorga) Ioana , Popescu Adrian Constantin , Popa Cicerone Laurentiu , Dobrescu Tiberiu Gabriel , Cotet Costel Emil
Published: August 2021

Considering the strong need for improvement of security and multimedia systems in the automotive industry, wiring harness production is becoming more and more important. Adapting to the integration of new technologies on the vehicle is a challenge for wiring harnesses manufacturers. Now the production of wiring harnesses is still quite dependent on human resources, the way of distributing the workload on the workstations having a large share in increasing productivity. Components such as terminals, connectors and seals are getting smaller and smaller, making the manual handling more difficult. A solution to this problem could be increasing the automation degree in wiring harness production. The objective of the research topic approached in this article is to identify solutions for optimizing the wiring assembly flow by partially automating the production flow. The concern for the application of automated processes in the production of car wiring is not new, but so far, the wiring manufacturers have been more focused on automating the prefabrication of the elements that compose the harness and not the wiring harness assembly line. From an economic point of view, the automation of the assembly flow would increase productivity by reducing fabrication time and the uncertainty given by the human resource dependence.
Solder joint reliability based on creep strain energy density for SAC305 and doped SAC solders
Authors: Vargas Cruz Ramiro Sebastian , Gonda Viktor
Published: August 2021

Parallel to the development of new lead-free solders, electronic packaging has gone through a considerable evolution. A redistribution of layers allows the increase of functionality by increasing the number of inputs/outputsin the packagewhile reducing the size. The reliability of the package is strongly influenced by the reliability of the interconnects. During production and service life, there are thermal processes involved that may lead to thermal fatigue. In this work, a two-dimensional finite elementmodel of a Fan-Out Wafer Level Packaging (FO-WLP) was built, and simulations of thermal test cycles were carried out varying the solder interconnect material: SAC305, SACQ, SACR, orInnoLot. A thermal oscillating load from –40°C to 125°C was applied to the packaging for three hours.State of the art concerning solder joint reliability models based on creep behavior reveals the benefit of using energy-based parameters, as cycles to failure are inversely proportional to the average creep strain energy density.Based on theaverage creep strain energy density simulation results, the reliability of the package withdifferent solderswas compared.The qualitative results suggestthat SACQ has a significant advantage in the operational lifetime compared toSACR, InnoLot, and SAC305.
Application of single minute exchange of die tool in a food industry company to eliminate waste
Authors: Kędziora Hubert , Trojanowska Justyna
Published: August 2021

Dynamically occurring changes in the economy and social environment require enterprises to monitor and improve the effectiveness of their production processes in order to remain competitive. The paper describes a research project aimed at improving the flow of materials by changing the organization of production and using Lean Manufacturing tool in a manufacturing company from the food industry, which is characterized by specific requirements and legal standards. Among others, a tool for organizing the workplace and a tool allowing to shorten the time of changeovers, taking into account the specific requirements of the food industry, were used in the research project. The effect of the implemented changes is an increase in production efficiency by 11% and obtaining annual financial benefits in excess of EUR 100,000. It should be noted that the implementation of the project did not require any capital expenditure. All tasks were completed within the working hours of the company’s employees.
Aspects regarding the organization of printing production in the context of Industry 4.0
Authors: Răcheru Răzvan-George , Adăscăliţa Lucia , Piţigoi Dorin-Vasile , Bălan Emilia
Published: August 2021

The development of information technologies has a strong impact on manufacturing systems, and the presence of the computer allows the efficient combination of various technologies needed for manufacturing into an integrated computer-controlled manufacturing system, which has also found utility in the printing field. The paper presents the results of the analysis of prepress, press (print) and postpress processes specific to printing companies in terms of integrated computer systems that make it possible to interconnect at the enterprise level. At the same time, were defined the stages, technological operations, procedures focused on the production structure through modern information and communication technologies. These represent goals of industrialization 4.0. Thus, functional and informational models, especially for prepress, were developed. The research methods involved in the study were observational, descriptive and correlational study. The results of the study indicate their usefulness to achieve high performance when raw printing materials are transformed into finished products.
The advantages of combining 3D printing with turning process. Case study
Authors: Negrău Dan Claudiu , Grebenisan Gavril , Gherghea Ion Cosmin , Anton Daniel
Published: August 2021

The paper presents a case study which the additive manufacturing technology is combined with finishing process by cutting operations (turning) for manufacturing a part. The part was manufactured through additive manufacturing, using a 3D printer and the and the finishing process is performed by a lathe, resulting in technological properties and the corresponding dimensional accuracy. The research paper also contains the analysis of the roughness and other properties of the material from which the final part will be made. The manufactured part will be used as a support for the blades of a fan during the assembly process, which emphasizes that a part obtained by additive manufacturing (3D printing) can replace a part obtained by casting or fabrication by total cutting. In conclusion, obtaining the manufactured part by combining the two manufacturing processes, the lead time and the production cost has been significantly reduced, while the quality of the obtained product also increased, obtaining a very good roughness.
Numerical-Experimental Study Regarding the Single Point Incremental Forming Process
Authors: Rosca Nicolae , Oleksik Mihaela , Rosca Liviu
Published: August 2021

The present paper proposes a numerical-experimental comparative study on the single point incremental forming process. A DC04 steel sheet with a thickness of 0.6 mm was used for both the numerical simulation using the finite element method and the experimental research. The type of trajectory used was a spiral trajectory and the finished part obtained was a truncated cone-shaped part. The analysis program used for simulation was Ls-Dyna. The simulations were performed in several variants: with a fixed mesh and with an adaptive mesh, using two different element formulations: 25 (Belytschko-Tsay formulation with thickness stretch) and -16 (fully integrated shell element modified for higher accuracy) and two contact types: automatic surface to surface (ASTS) and forming one way surface to surface (FOSS). The results of the numerical analysis and of the experimental research were focused on determining the major strain, minor strain, thickness reduction and forces at the end of the single point incremental forming process, as well as determining the processing time.
Changes of Structure and Physical-Mechanical Properties in Alloy Steels Thermochemically Treated by Plasma Nitriding
Authors: Ciofu Florin , Bibu Marius
Published: August 2021

Plasma nitriding is a method of surface modification using a glow discharge technology to introduce nitrogen into the surface of a metal, which subsequently diffuses into the material. The main advantages of plasma nitriding over conventional nitriding processes are: reduced cycle time, controlled growth of the surface layer, elimination of white layer, reduced distortion, no need of finishing, pore-free surfaces and mechanical masks instead of copper plating. The process is especially suitable for complex parts that are intensively solicited by wear, fatigue, contact pressure, shocks, possibly also to corrosion. It is applied in order to bring the metallic products in a state favourable from the point of view of structure, chemical composition and internal stress state. The paper presents an analysis of the structures and characteristics of a widely used structural steel 39 - CrAl6. As a result of plasma nitriding, a surface layer with high wear and fatigue resistance was created on the surface of the material. Also, between the surface layer and the base material was interposed a hard substrate with high wear resistance having a bainitic / martensitic structure.
Comparison of Artificial Neural Network Model and Response Surface Methodology for Springback Prediction
Authors: El Mrabti Iliass , Touache Abdelhamid , El Hakimi Abdelhadi , Chamat Abderahim
Published: August 2021

In sheet metal manufacturing, the ability to predict failures, such as springback, wrinkling and thinning, are of high importance. The objective of this study is to compare the response surface methodology (RSM) and the artificial neural network (ANN) model for predicting springback during the deep drawing process. In this investigation, friction coefficient, punch speed and blank holder force were considered as input variables. Sample data were planned by the complete factorial design and obtained via numerical simulation. To compare the RSM and ANN models, a goodness of-fit test was performed. The results of the two methods are promising and it is found that the ANN results are more accurate than the RSM results.
Optimization of automotive cooling systems characteristics using finite element analysis
Authors: Chiriac George Gabriel , Dumitras Catalin Gabriel
Published: August 2021

Due to a continuous evolving automotive industry, car manufacturers continuously develop new technologies to stay competitive on the market. Most of the modern cars are equipped with electronic devices used for functional or multimedia purposes. Electric cars have additional components used for charging and battery management. All the electronic components used in cars dissipate heat during functioning and all of them need cooling in order to keep a proper functioning temperature. Cold plates are a very efficient cooling solution used in most of the cars. The advantage of the cold plates is that it can dissipate a high amount of heat, have a small volume and can be placed in closed or tight areas. In order to enhance the thermal transfer between the cold plate and the cooling fluid, turbulence enhancement geometries are used inside the cold plate. The purpose of this paper is to use finite element analysis to compare different positions of one protrusion in the cooling channel to enhance the cooling process. The goal is to see if the protrusion position influences the cooling and which placement is more efficient. The second evaluation criteria of the efficiency is to keep a low-pressure drop inside the system.
Sizing and shape optimization material use in 10 bar trusses
Authors: Petrović Nenad , Kostić Nenad , Marjanović Vesna , Cofaru Ileana Ioana , Marjanović Nenad
Published: August 2021

Truss optimization has the goal of achieving savings in costs and material while maintaining structural characteristics. In this research a 10 bar truss was structurally optimized in Rhino 6 using genetic algorithm optimization method. Results from previous research where sizing optimization was limited to using only three different cross-sections were compared to a sizing and shape optimization model which uses only those three cross-sections. Significant savings in mass have been found when using this approach. An analysis was conducted of the necessary bill of materials for these solutions. This research indicates practical effects which optimization can achieve in truss design.
The Topological Optimization and the Design for Additive Manufacturing of a Steering Knuckle for Formula SAE Electric Vehicle
Authors: Zach Theodor-Florian , Dudescu Mircea-Cristian
Published: August 2021

Formula Student represents the main motorsport activity for future professionals during their academic preparation. There is intensive migration from the prototypes with an internal combustion engine to electrical vehicles. The challenge of electric vehicles is the weight of the batteries which has to be compensated. The Topological Optimization process represents a method of removing volume and mass of the component (elements of mesh) with the aid of the discretization allowed by the finite element method (FEM) until a mass or stress constraint is attained. The results come in a complex shape, the material being kept only in the stressstrain directions. The manufacturing process is usually as complex, being employed high complexity technologies such as Selective Laser Melting (SLM). Improved strength-to-weight ratio materials are to be considered to obtain the most performant design of a specific component. The present paper presents the topological optimization process of the steering knuckle for the Formula Student electric vehicle of ART-TU Team of Technical University of Cluj-Napoca. It means that the part is simulated and optimized through Ansys Static Structural and there is done post-processing of the component along with Data Validation. The conclusions consist of the viability of the Topological Optimization process when designing complex components for performance automotive.
Development of Brasov SMEs through public financing of innovative products or services
Authors: Stelea Nicoleta , Calefariu Gavrilă
Published: August 2021

The profit of organizations can be increased by the approach to existing funding for the private actors (SMEs/Micro-enterprises), namely those through the Regional Operational Program (ROP) 2014-2020 and the various projects financed and implemented in Braşov County. This analyze was performed according to the efficient systematization of the services and innovative products obtained; the way how they apply and use the funding to achieve the overall objectives of the financed project and the indicators provided in the projects. Following these, a number of 10 projects implemented in Braşov were chosen, examples of good practice, with a final report as deliverable. It includes the results obtained and the efficiency solutions, as well as certain mistakes that should not be repeated. This paper makes, for the first time, a synthesis of the issues in the field of microenterprises financing in Braşov and then an analysis of the phenomena that occurred during the implementation of the projects. Taken in consideration the new funding for SMEs in the period 2021-2027, we need as many successful projects and beneficiaries as possible, for accessing and using existing public funds in Braşov City and County.
Assessment of process stability and capability in a manufacturing organization: a case study
Authors: Simion Carmen
Published: August 2021

Quality is considered asthe principal factor that determines the long-termsuccess or failure of any organization. Organizations perform quality control by monitoring process output using Statistical Quality Control, performed as part of the production process (Statistical Process Control, SPC) or as a final quality control check (Acceptance Sampling).SPC is a major quality management statistical tool and its instruments (control charts and capability analysis) are applied to virtually any type of organization (manufacturing, services or transactions - for example, those involving data, communications, software, or movement of materials). The aim of this paper is to present a case study, realized in a manufacturing organizationfrom Sibiu, for a new product used in the automotive industry to check its conformance to designed requirements. The output data were analyzed using statistical analysis software Minitab.
Technical Considerations on the Management of Coastal Areas Rehabilitation Projects
Authors: Grigoras Georgiana , Mihalache Ionuţ Cristian , Edelhauser Eduard
Published: August 2021

Coastal erosion contributes to the loss of particularly valuable land, which can damage coastal ecosystems and cause economic and social damage to the area where they occur. Coastal erosion is a natural process that affects shores around the world. The article present aspects of coastal erosion in Romania as well as some solutions proposed to reduce this phenomenon. Submerged structures are exposed to erosion therefore a close monitoring is necessary. A malfunction will result in the damage of the structure as well as endangering marine wildlife. The proposed solutions are meant to protect the coastal area against erosion, protecting the shore, adjacent land and ecosystems. These solutions will also protect the economic infrastructure and social objectives endangered by marine erosion. A monitoring program will be implemented for a medium and long term, supporting the maintenance operations.
A Validation Model for Ethical Decisions in Artificial Intelligence Systems using Personal Data
Authors: Stefan Radu , Carutasu George
Published: August 2021

Decision making, a fundamental human process, has been more and more supported by computer systems in the second part of the last century. In the 21st century, intelligent decision support systems utilize Artificial Intelligence (AI) techniques to enhance and improve support for decision makers. Often decisions suggested by an AI system are based on personal data, such as credit scoring in financial institutions or purchase behavior in online shops and the like. Beyond the protection or personal data by the General Data Protection Regulation (GDPR), developers and operators of decisional AI systems need to ensure ethical standards are met. In respect to individuals, arguably the most relevant ethical aspect is the fairness principle, to ensure individuals are treated fairly.

In this paper we present an evaluation model for decision ethicality of AI systems in respect to the fairness principle. The presented model treats any AI system as a “black-box”. It separates sensitive from general attributes in the input matrix. The model measures the distance between predicted values on altering inputs for sensitive attributes. The variance of the outputs is interpreted as individual fairness, that is treating similar individuals similarly. In addition, the model also informs about the group fairness. The validation model helps to determine to what extent an AI System, decides fairly in general for individuals and groups, thus can be used as a test tool in development and operation of AI Systems using personal data.
New approach of designing robotics production systems using immersive virtual reality environment
Authors: Holubek Radovan , Bočák Róbert , Prajová Vanessa
Published: August 2021

Production requirements are growing and companies needs to adapt to the latest trends with state-of-art technologies. Virtual reality (VR) technology promises big changes in Industry sector, even this technology is still evolving. This immersive technology allows to visualization and interaction of complex engineering data in virtual environment, provide various inspection of 3D objects and allows to communicate changes on objects or process between production teams and customers. This paper discus about potential of VR systems in Industry and purpose of usage to improve development process and the use of this technology in the design of future robotic systems. The goal is to compare causal designing methods of robotic work station and method with using VR environment and their possibilities. Development supported by VR systems shortens preproduction phase and brings to user immersive experience with designing product or process without creating physical prototype or real production systems.
Mechatronic Design of a Four-Wheel drive mobile robot and differential steering
Authors: Crenganis Mihai , Biris Cristina , Girjob Claudia
Published: August 2021

This paper presents, the development of an autonomous mobile robot with a four-wheel drive and differential locomotion. The mobile robot was developed in the Machines and Industrial Equipment Department from the Engineering Faculty of Sibiu. The main purpose of developing this type of mobile platform was the ability to transport different types of cargo either in industrial spaces or on rough terrain. Another important objective was that this platform could be driven in confined or tight spaces where a high degree of manoeuvrability is necessary. The great advantage of this type of mobile platform is the ability to navigate through narrow spaces due to the type of locomotion implemented. The fact that the robot has four driving wheels gives it the ability to travel on rough surfaces and easily bypass obstacles. Another great advantage of the developed mobile robot is that it has a reconfigurable structure. The drivetrain is interchangeable, it can adopt both classic wheels and Mecanum wheels. The first part of the paper presents some general aspects concerning mobile robots and two types of traction wheels used in mobile robotic structures. Subsequently, the paper presents the steps taken in the development of the mobile wheeled platform. At the end of the paper, the electronic part that will be implemented in the structure of the robot is described. The command and control of the entire mobile platform will be described in some future work.
Incremental forming using KUKA KR210-2 industrial robot - research regarding design rules and process modelling
Authors: Bârsan Alexandru , Racz Sever-Gabriel , Breaz Radu
Published: August 2021

Incremental sheet forming (ISF) process show a great potential in the manufacturing of small series production or prototype development parts. One of the sheet metal forming process, where the contact between punch and metal sheet is in a single point, is known as single point incremental forming (SPIF). The part is manufacture with a simple tool, known as punch, that performs a series of combined movements on the vertically and horizontally directions. The paper introduces a study regarding the design rules and process modelling of this unconventional process, by means of a KUKA KR210-2 industrial robot as technological equipment able to control the correlated movement of the punch. Supplementary, the design of the experimental layout, the process simulations and the singularity problems are considered.
Position control for hybrid infinite-continuous hyper-redundant robot
Authors: Pană Cristina , Vladu Cristian , Pătraşcu-Pană Daniela , Besnea (Petcu) Florina , Cismaru Çtefan , Trăşculescu Andrei , Reşceanu Ionuţ , Bîzdoacă Nicu
Published: August 2021

This paper presents a new conception and analyzes a hyperredundant continuous robot (continuous style manipulator), drive system, and control strategy. The robot includes ten flexible segments and can be extended to several components as needed. The chosen hyper-redundant robot has a continuous infinite hybrid structure (HHRIC), based on hydraulic control with a rheological element. This system combines the advantage of a joint-level drive with a lightweight construction similar to the base-driven robots. It is suitable for tasks such as wiring in hard-toreach areas (caves, subaccounts, steep areas), transportation of fluids or food to areas affected by natural disasters (people buried under ruins), exploration in difficult areas (speleological research). Generally, the control algorithms for hyper-redundant robots are specific to the robots’ constructive particularities to which they have applied and the environment in which they operate. Experimental results validate the proposal robot design and control strategies in virtual reality. As a result, it is concluded that hyper-redundant robots and immersive technologies should play an essential role soon in automated and teleoperation applications.
Case studies - Research and technological solutions to prevent sand production in the gas wells from the Getic Depression
Authors: Lupu Diana-Andreea
Published: August 2021

A frequent challenge encountered in the exploitation of mature gas fields located in the Getic Depression is sand production. Causes of sand production are mainly related to degree of rock consolidation, lithology, increasing water production and production rates. The effects of sand production are multiple such us low productivity of the gas wells, accumulation into the surface equipment, erosion of downhole and surface equipment, plugging the perforation zone and casing damage. The current paper will address the sand production- challenges and new perspectives in remedial work of wells which are producing from gas reservoirs located in Getic Depression. The article presents through some case studies the research performed for the implementation of the frac-pack technology in some gas wells.
Natural gas hydrates vs. induced dysfunctions in the hydrocarbon extraction process
Authors: Lupu Diana-Andreea , Stefanescu Dan-Paul
Published: August 2021

Cantoned fluids in porous-permeable or fractured media of reservoirs have acquired during the geological time special properties. The fluids from the reservoir could be or not a mixture of reservoir water, liquid hydrocarbons and gaseous hydrocarbons. Considering if inside of a reservoir there are two types of substances like natural gas and reservoir water which may be in the form of vaporous than the condition of saturation of gases with water vaporous is fulfilled. This process is taking place due to thermodynamic equilibrium resulting the so-called gas humidity. This state corroborated with a certain chemical composition plus favourable values of pressure and temperature may be decisive in the appearance of hydrates. In this scientific paper they will be presented from a theoretical and practical point of view the favourable conditions of gas hydrates appearance and the specific ways of inhibiting the formation of this compounds. A case study in which through modelling and numerical simulation of the behaviour of a productive natural gas well will provide a series of data related to this phenomenon. The specific modelling and numerical simulation was adapted to the conditions of formation and subsequently the elimination of the appearance of hydrates.
The Petroleum Systems from the Western Black Sea Basin, Romania
Authors: Mitrea (Rosu) Ioana-Cornelia , Batistatu Valentin-Mihail , Lungu Ionut
Published: August 2021

Although oil production has a long history in Romania, the offshore discoveries from the Western part of the Black Sea are still relatively newly developed and with further potential to be revealed. To find the best places for new wells, as well as making new oil field discoveries, it is very important to understand the petroleum system of the area. If the elements of the petroleum system are well understood, then the potential of the Black Sea will become bigger, as the complexity of the area will be acknowledged. Two major petroleum systems were discovered in the area, the thermogenic system, and the biogenic system. The thermogenic system is corresponding to the shallow area of the Black Sea, where current productive fields are, while the biogenic system is corresponding to the deeper area, currently being in the exploration stage. The purpose of this article is to present both petroleum systems from the Black Sea Romania, their elements, the evolution they had, and the major differences between the two.
Greenhouse Gases Assessment in the Context of the Covid-19 Pandemic
Authors: Stoica Monica Emanuela
Published: August 2021

Greenhouse gases are: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride. In December 2020, the European Council approved a new target for reducing greenhouse gas emissions by 2030 and a net domestic emission reduction of at least 55% compared to 1990, and climate neutrality for 2050. Careful monitoring of emissions is needed to achieve these goals. The paper aims to evaluate and compare the carbon dioxide emission coefficient, in the case of burning different fuels: petroleum fuels and biofuels. The calculation model was developed based on the mathematical relationships taken from specific publications. Kerosene, Liquiefied Petroleum Gas, Gasoline COR 95 Euro 5 and Diesel Euro 5 are the petroleum fuels used in the study. The used biofuels are: Bioethanol, Biobuthanol, Biodiesel (soybean) and Biodiesel (rapeseed). The results provide data on the amount of CO2 that reaches into the atmosphere. Based on the information obtained, a fuel ranking can be made and decisions can be taken regarding their choice.
Considerations on Ergonomic Issues in Physiotherapy Activity
Authors: Darabont Vlad Andrei , Darabont Doru Costin
Published: August 2021

Nowadays, the ergonomic issues become more and more important in all economic activity domains. Work-related Musculoskeletal Disorders (MSDs) represent the main problem generated by the poor ergonomic design of the workplaces. The healthcare domain involves high level ergonomic risks related to physical and mental load of the work which could lead to MSDs. The paper presents an analysis of these ergonomic risks for physiotherapy activity and identifies potential measures to improve the health and safety in this domain. The physical load of the physiotherapist’s work is generated by the risk factors such as awkward postures, repetitive movement or working with patients with motor disabilities. The mental load of the physiotherapist’s work depends on risk factors such as working with patients with cognitive impairment and daily or weekly patient flows. The proposed preventive measures are organisational and technical. The organisational measures are based on the requirements of the occupational health and safety (OHS) legislation and on the good practice examples. The technical measures are based on the analysing the documentation of physiotherapy modern equipment. The results of the study can be used to improve the ergonomics and the health and safety of any workplace in physiotherapy activity.
How to keep your staff healthy in the educational sector?
Authors: Rotaru Mihaela
Published: August 2021

The purpose of the paper is to identify risks and challenges for alternative forms of work during online classes for teaching personnel. Musculoskeletal disorders (MSD) affect the body’s bones, muscles, joints, ligaments/tendons, and nerves. Musculoskeletal health risk in the educational sector should be taken into consideration to ensure the safety and healthy employees, especially when online classes require a physical inactivity and a prolonged sitting in front of the computer. MSD management requires an integrated approach integrating wellbeing with a focus on prevention, recognizing physical, social and emotional influences and early intervention. Workplace wellness has been a valuable tool and technique for maximizing employee health and workplace efficiency.
Aspects regarding skills and education related to Industry 4.0
Authors: Banciu Felicia Veronica , Feier Anamaria Ioana
Published: August 2021

People is changing. Technology is changing. Economy is changing. Society is changing. Education is changig. In the Industry 4.0 the digitalization and VR, AR, CPS, IoT, ICT, AI assures higher precisions, higher productivity, mass customisation, less waste, and less pollution and contributes to the society change. All the applied and ready to apply technologies receive digital component, as result of the rapid development of information and communication technology. The main objective of the paper is to see in specialized literature what are the skills required by Industry 4.0 (I.4.0), what are the means associated with the concept of Education 4.0 (E.4.0) to obtain them, and to what extent education systems are adapting to these new requirements, which are constantly changing. In addition, it is presented the current situation regarding education perspective and some directions of action, and at the end, a number of conclusions focused on what we could do to all benefit from technological progress in industry as well as in education.
Mixing control in a continuous-flow microreactor using electro-osmotic flow
Authors: Siraev Ramil , Ilyushin Pavel , Bratsun Dmitry
Published: August 2021

In recent years, pharmaceutical production has been stimulating the gradual miniaturization of continuous-flow chemical reactors. This process eventually resulted in the emergence of a new generation of microreactors. The advantages of these new reactor types are the flexible production that allows us to quickly reconfigure the scheme, small reactant quantities used for the synthesis, the control of the main reaction parameters with high accuracy. Nevertheless, a decrease in the thickness of the channels where the species contact and react forces us to search for new non-mechanical mechanisms for mixing. This problem is relevant for the slow reaction occurring in a slot where diffusion alone cannot provide mixing at reasonable distances from the entrance. It is also true for the fast reaction that takes place in a frontal manner. In this work, we consider the efficiency of mixing the reactants induced by electro-osmotic flow in a Hele-Shaw configuration with non-uniform zeta potential distribution. As a test reaction, we take the neutralization reaction with simple albeit non-linear kinetics. The reaction occurs between two miscible solutions, which are initially separated in space and come into contact in a continuous-flow microreactor. The reaction proceeds frontally, which prevents the efficient mixing of the reactants due to diffusion. Using direct numerical simulations of 2D and 3D flows, we demonstrate that the zeta potential applied to boundaries can effectively control the mixing rate of fluids by lengthening the front of the reaction. This approach makes it possible to increase the yield of the reaction product.
A Fileira da Cortiça em Portugal – Posicionamento e Competitividade
Authors: Coelho Inocêncio Seita , Pestana Miguel
Published: August 2021

Portugal é o principal produtor e transformador mundial de cortiça. Esta posição foi assumida após a Guerra Civil de Espanha, em que Portugal ultrapassou aquele país na liderança mundial (DIAS, 2005).

A área ocupada pelo sobreiro, a nível mundial, situa-se próxima de 2,7 milhões de hectares (correspondendo a 350 mil toneladas de cortiça), distribuída essencialmente na zona Mediterrânea com influência atlântica. A Península Ibérica detém 56% da área total, Portugal com 33% e Espanha com 23% (PESTANA, 2005).

Portugal possui uma área com sobreiros de 713 mil hectares (DGRF, 2006). Em 83% desta área, os povoamentos têm um estado de vitalidade bastante bom ou bom, com um apreciável potencial produtivo de cortiça amadia. Exportou 128.465 toneladas em 2001, com um valor de 880,8 milhões de euros. O país produz 54% da produção mundial de cortiça (em 2001 chegou a 340.000 toneladas), o peso da exportação desta matéria-prima é, aproximadamente, um quarto do total exportado pelo sector florestal e representa quase 3% do cômputo das exportações totais (INE, 2006).

A importância estratégica do sobreiro e da cortiça, para Portugal, está reconhecida na Estratégia Nacional para as Florestas (DGRF, 2007).

Três países da União Europeia (Portugal, Espanha e Itália) são líderes na produção, transformação e comércio de cortiça. Portugal transforma quase 37% do total mundial. As pequenas empresas são responsáveis pela transformação de 70% da produção nacional.

Por tudo isto, é fácil de entender a importância estratégica desta fileira para o nosso país, pelo que faremos um diagnóstico e uma análise prospectivos deste sector económico e utilizaremos uma análise SWOT para aferir a competitividade do mesmo.
Genusstherapie statt Stigmatisierung bei Adipositas
Authors: Arnold Christopher , Linden Michael , Warnke Max Holger
Published: August 2021

Von Adipositas wird nach medizinischen Kriterien bei einem Body-Mass-Index über 30 kg/m2 gesprochen. Adipositas ist mit einer erhöhten Rate an somatischen und psychischen Krankheiten assoziiert. Gesellschaftliche Normen in westlich geprägten Ländern sind durch eine Ablehnung von "fett sein" und eine Tendenz zur Diskriminierung von Adipösen geprägt, was auch einer Selbstdiskriminierung und subjektivem Leiden der Betroffenen Vorschub leistet. Technischer Fortschritt und die heutige Arbeitsgestaltung erlauben jedoch adipösen Menschen, unbeeinträchtigt am Leben in der Gesellschaft und dem Arbeitsleben teilzunehmen.

Therapiemaßnahmen dürfen nicht nur auf Diäten und eine Gewichtsreduktion abzielen, sondern müssen vorrangig auch das Selbstwertgefühl und die Lebensqualität der Betroffenen zum Gegenstand haben. Interessante Therapieansätze lassen sich aus der positiven Psychologie, der Well-being-Therapie und der Genusstherapie ableiten.
Allenes in Diels–Alder Cycloadditions
Authors: Hopf Henning , Sherburn Michael S.
Published: August 2021

For a long time, allenes—and cumulenic systems in general—played a relatively minor role in Diels–Alder cycloadditions. This situation has changed, since allenes are more readily available and as their unique stereochemical features in [4+2]cycloadditions are more widely recognized. This review presents a comprehensive overview of allenes in Diels–Alder processes using selected examples. Allenes in dienes, dienophiles and cycloadducts are covered, inter- and intramolecular Diels–Alder cycloadditions are discussed, and stereochemical features of the addition process are described. Areas of emerging importance are also covered, including allenic components in dehydro-Diels–Alder processes, and dendralenic allenes in Diels–Alder sequences for the rapid generation of target-relevant molecular complexity. Preparatively useful methods for allenic precursor synthesis are also discussed.

1 Introduction

2 Allenic Dienes

2.1 Vinylallenes

2.2 Bisallenes

2.3 Cross-conjugated Allenes

3 Allenic Dienophiles

4 Intramolecular Diels–Alder Cycloadditions

5 Allenic Cycloadducts

6 Conclusions and Outlook
Unplanned Hospital Readmission and Visit to the Emergency Room in the First Thirty Days after Head and Neck Surgery: A Prospective, Single-center Study
Authors: Chiesa-Estomba Carlos Miguel , Sistiaga-Suárez Jon Alexander , González-García José Ángel , Sarasola Ekhiñe Larruscain , Vilanova Ariadna Valldeperes , Altuna Xabier
Published: August 2021

Introduction Head and neck surgery remains a complex field; the patients can suffer important functional or life-threating complications after treatment that need unplanned readmissions, increasing the cost related to the treatment.

Objective To evaluate the incidence risk factors and causes associated with 30-day unplanned hospital readmission and visit to the emergency room (ER) after surgery for head and neck cancer.

Methods Prospective, longitudinal, nonrandomized study.

Results A total of 834 patients were included, 726 in the major surgery group and 108 in the minor surgery group. The 30-day readmission rate for all causes was of 7,9% for the patients treated by a major surgery and of 0% for the patients treated in the outpatient clinic for minor procedures, to a total readmission rate of 6,8%. The rate of visit to the emergency room for all causes in the first 30 days was of 14% for the patients treated by a major surgery and of 2,7% for the patients treated in the outpatient clinic.

Conclusion Major surgery, the American Society of Anesthesiologists (ASA) status and type of wound are conditions related to unplanned readmission or visit to the ER in the first 30 day after discharge. The most commonly associated causes are infections or wound complications. An evidence-based risk stratification of the patients can be important to improve decision-making and resource utilization. An educational strategy can provide possible ways to improve the rate of readmission and reduce the amount of money expended by healthcare systems.