INFLUENCE OF DEFOCUS POSITION ON LASER CUTTING PROCESS IN SHEET STEEL

Some researches about influence of defocus position to carry out laser cutting technological process through melting when producing lamellae for electric motors are presented here. Experimental series at defocus position Δf in the range – 3, 5 mm to + 3, 5 mm with two grade electrical steels M250-35A and M530-50A are described, too. The experiments are performed with a technological laser system TruLaser 1030. Functional dependencies of cutting width from defocus position b = b (Δf) have been shown. Theoretical relationships connected to the change of impact on a unit of area working spot over power density qs of the laser radiation and interaction time tproz (respectively cutting speed v), are examined to

Laser Marking Methods

Different methods for laser marking are systematized and discussed in the paper. Today in the practice there are many different methods that could be used to realise high quality on the workpiece of various materials with various shapes. Some materials could be marked only by marking or engraving without special requirements and difficulty, while for other materials one can choose the concrete method about the kind of material, marking type, and the specific needs of the production process and the geometry of detail. This makes it necessary to know, to summarise and systematize in a database all methods for particular lasers and materials, in order to quickly and flexibly respond to the specific needs of each customer by the manufacturies on marking systems. The report studies the specific opportunities and fields of applications of different methods for marking with laser

LASER AS A DEVICE FOR MEASUREMENT OF THIN THREADS - A SCHOOL LABORATORY EXPERIMENT IN PHYSICS

The physics of the last century is included in all EU curricula and emphasis in education is shifted from content to the forms, methods and means of teaching and learning. Different kinds of lessons (including laboratory classes) and their didactic structure are subject to the understanding, adoption and creating conditions to build motivation to learn physics and astronomy, active utilization of physical knowledge and building cognitive and practical skills. Performance of demonstration and laboratory classes using a laser device is a type of teaching strategy to good education in physics. Properties of laser light as observation, classification, communication, drawing conclusions, planning, interpretation and forecasting, are particularly suitable when monitoring and studying the phenomena of interference and diffraction. Through both qualitative and quantitate ways, in this paper is presented a physical experiment for measurement of thin threads in a High school from students. Experimental skills will enhance interest in physics and especially to modern applications of laser devices, as well as career guidance of students

Factors influencing the color laser marking

In recent years, conventional techniques of marking on some parts of different work pieces, as well as on packages with color printing are increasingly being displaced by laser color marking. Colored marking of stainless steel could be realized by the process annealing. The advantages offered by the new technology are in greater accuracy, speed, flexibility and high amount of recorded information per unit area (bar and matrix codes).In the report are discussed and analyzed the factors influencing on the specific to the process of laser color marking at the products of CrNi steel.  The study was conducted using a commercially available industrial pulsed fiber laser. Presents the results of the measurements and analysis of the influence of laser process parameters on the color contrasting obtained. In this case, the relevant parameter, the field of high frequencies and low pulse energy were examined. The present thesis describes studies a properties of the laser radiation, such as, pulse width, average power, the intensity and beam diameter

STUDY OF AUXILIARY GAS PRESSURE ON LASER CUTTING TECHNOLOGY

Two types of electrical sheet steel M250-35A and M530-50A were used to cut by melting with a TruLaser 1030 technological system. It was observed that pressure of auxiliary gas had a major effect on kerf width b and cut angle deviation α. Nitrogen as an assisted gas has been taken. The basic parameters as laser power, cutting speed, focus position were constantly supported and the pressure was changed from 4 bar to 20 bar by step 2 bar. As well as the experimental results of gas pressure on entrance and exit kerf widths, have been analyzed and discussed in this study

Arquitectura y gastronomía

[ES] La arquitectura y la gastronomía a lo largo del tiempo, han ido evolucionando conjuntamente, proporcionando diferentes experiencias al comensal. Con este trabajo de Final de Grado, se pretende estudiar desde un punto arquitectónico las características de diferentes restaurantes con Estrellas Michelin. Se analizarán a partir de diferentes factores, influyentes en el diseño y en la configuración de estos espacios gastronómicos. De esta manera se intentará realizar una guía tipo que sirva de instrumento base, para un diseño óptimo, de restaurantes de alta gastronomía.[EN] Architecture and gastronomy over time have evolved together, providing different experiences for diners. With this Final Degree project, the aim is to study from an architectural point of view the characteristics of different Michelin Star restaurants. They will be analyzed based on different factors influencing the design and configuration of these gastronomic spaces. In this way an attempt will be made to create a type guide that will serve as a basic instrument, for optimal design, of fine dining restaurants.Boyuva Deneva, H. (2020). Arquitectura y gastronomía. http://hdl.handle.net/10251/150478TFG

A task for laser cutting of lamellae with TruLaser 1030

The growing development of manufacturing, automotive, aerospace and other sectors in the industry generates the necessity to continuously expanding on modifications of electrical machinery and equipments which are used in them, as well as to improve their performance and reliability. The report presents some results from a study to the process of laser cutting through melting on lamellae for rotor and stator packages by using the laser system TruLaser 1030. Some functional dependencies are offered between physical quantities describing the cutting process by melting and technological parameters aimed providing the quality requirements. With a software TruTops to optimize the cutting out are shown the results of studies to determine the technological working time for cutting of a concrete stator lamella.

LASER TECHNOLOGIES – MASTER’S PROGRAM BETWEEN TWO EUROPEAN UNIVERSITIES OF APPLIED SCIENCES FROM LATVIA AND GERMANY

Laser equipment and laser technologies are among the most modern, fastest growing and most promising branches of science and technology in the 21st century. The first laser was created in 1960 and for about 55 years, today there is hardly any area of our lives in which lasers and related technologies are not applied. Laser systems and related innovative technologies ensuring high precision, productivity and quality of production have been developed and proposed worldwide from hundreds of scientific research institutes and companies. The Master's program is accredited in two European universities in Germany and Latvia and allows for the production of double diplomas. The course is based on international experience and reflects the most recent advances in laser techniques and technologies. The program examines the physical fundamentals and technical realization of various types of laser systems and their specific characteristics. First the necessary foundations of the laser physics, optics and the interaction of radiation with matter are presented, followed by more detailed examination of the problems of laser technology in various fields of science, technology and industrial production. Basic physical and technical solutions of the building blocks of lasers are presented in details, such as: optical resonators, active environments, excitation systems, management systems, laser generation. As well as specific issues and practical examples of industrial applications are described

Centro Gastronómico Ruzafa.

[ES] Como es común el crecimiento de las grandes ciudades supone la absorción de pequeños pueblos periféricos, que se acaban convirtiendo en barrios muy particulares. Tal es el caso del pueblo de Ruzafa, convertido en uno de los barrios más emblemáticos de Valencia como resultado de la fusión del núcleo histórico de esté con el denominado Ensanche valenciano. Su reciente auge lo ha llevado a una situación de gentrificación, es decir, se origina una amenaza al pequeño comercio y a los habitantes del barrio por la llegada del ocio y turismo masivo. Es por ello que se propone una actuación que potencie la actividad del Mercado de Ruzafa conectándolo al Mercado Central y la Huerta Sur, generando un eje gastronómico-cultural. El edificio planteado pretende fomentar la gastro-cultura del barrio a través de actividades colectivas enfocadas hacia la gastronomía, la agricultura y la artesanía. De manera que se produzca una sinergia entre las diferentes generaciones y culturas que conviven en él, con el apoyo de personal especializado.[EN] As it is common, the growth of big cities supposes the absorption of small peripheral towns, which end up becoming very particular neighborhoods. Such is the case of the town of Ruzafa, which has become one of the most emblematic neighborhoods of Valencia as a result of the fusion of the historic nucleus of this with the so-called Valencian Ensanche. Its recent peak has led it to a situation of gentrification, that is, a threat to small businesses and the inhabitants of the neighborhood is created by the arrival of leisure and mass tourism. That is why it is proposed that enhances the activity of the Ruzafa Market by connecting it to the Central Market and the Huerta Sur, generating a gastronomic-cultural axis. The proposed building aims to promote the neighborhood's gastro-culture through collective activities focused on gastronomy, agriculture and crafts. In such a way that there is a synergy between the different generations and cultures that coexist in it, with the support of specialized personnel.Boyuva Deneva, H. (2022). Centro Gastronómico Ruzafa. Universitat Politècnica de València. http://hdl.handle.net/10251/182002TFG

A single-center study of bone mineral density in adult patients with severe hemophilia A in correlation with markers of bone metabolism

Introduction: Osteopenia and osteoporosis are well-known hemophilia A comorbidities. The pathogenesis of bone turnover alteration resulting in reduced bone mass includes impaired osteoblastic differentiation and disinhibition of RANKL-induced osteoclastogenesis as a result of a low FVIII level. Aim: To evaluate the bone mineral density (BMD) in adult patients with severe hemophilia A and assess a possible correlation with the bone remodeling biomarkers OPG/RANKL, CTX-1, osteocalcin, and Vit D. Materials and methods: 28 male subjects with severe hemophilia A and 33 age-matched controls were recruited. The biomarkers were tested with the ELISA assay and BMD with DEXA of the lumbar spine (LS) and total hip (TH). Results: The patients had lower LS-BMD (−0.955±0.145 vs. 1.118±0.079, p=0.05) and TH-BMD (−0.840±0.147 vs. 0.951±0.075, p=0.05) than those of the controls. The TH T-scores were −1.41±0.91 vs. 0.4±0.49 (p=0.05) and the LS T-scores −1.16±1.046 vs. 0.14±0.72 (p=0.05). 66.6% of patients under 50 years had osteopenia and 8.3% had osteoporosis. Fifty percent of those over 50 years old had osteopenia and 20% had osteoporosis. We found significantly higher OPG levels (123.69±107.05 vs. 41.98±18.95, p=0.05) than that in controls and lower sRANKL levels (23.49±29.39 vs. 131.32±201.27, p=0.05) and sRANKL/OPG ratio (0.27±0.35 vs. 5.28±10.01, p=0.05) than those in controls. A positive correlation was found between sRANKL and the BMD T-score of lumbar spine (p=0.001) in the patient group. Conclusions: sRANKL level and ratio can be used as predictors of low BMD