An Efficient Solution for Water Oxygenation

The paper presents a new constructive solution for fine bubble generator, used for water oxygenation. The novelty is the fact that the air entering nozzles in water (Ø0.5•10-3 m) were performed by spark erosion. The advantages of this constructive solution that generate a pressure loss much lower than that which appears at porous diffusers, are revealed. Therefore, there is an economy of electricity at the compressor station that provides the compressed air required for water oxygenation

Research Regarding the Determination of the Power Consumed By Viscous Friction between the Rotors and the Case at a Rotating Volumetric Pump

In the first part of the paper the power consumed to overcome the viscous friction between the rotors and the case in case of a rotating volumetric pump is calculated. An experimental stand used to test this new type of volumetric pump with rotors profiled is presented; the power at the working machine couple is determined and an energy balance of the installation is issued

Increasing the energy conversion efficiency for shrouded hydrokinetic turbines using experimental analysis on a scale model

The objective of the paper is to study the influence of certain shroud types suitable for horizontal axis hydrokinetic turbines using experimental testing in order to increase the energy conversion efficiency. The scale model of the shrouded hydrokinetic turbine is tested on a dedicated experimental bench for axial hydraulic turbine models. Two types of shrouds were tested in order to be compared: convergent shroud and divergent shroud. The rotor and shroud were made using 3D printer technology and were tested at a water velocity of 0.9 m/s on the closed-circuit testing bench. The testing facility allows the determination of the power extracted for each shroud at five distinct positions. Thus, the rotor can be moved within the shroud from inlet to outlet in order to establish the proper operating position. The mechanical power is measured using a torque transducer and an electromagnetic particle brake. The testing results will be analysed based on the variation of power curves obtained for different shroud types and operating positions. The optimum design and the best operating position will be recommended by comparing the testing result with the data collected from the bare turbine using the same rotor placed directly in free flow

Quo Vadis „Living Human Treasures”?

„Living Human Treasures” (LHT) is a program supported by the United Nations Educational, Scientific and Cultural Organization (UNESCO). According to the Regulation of the Ministry of Culture in Bucharest, the title „Living Human Treasures” is the life contingency, personal and in transmissible. The person „must, simultaneously fulfill bearing, preserving and creating qualities of intangible heritage, be able to transmit traditional cultural models and be recognized as so by other LHT and the scientific community”. In six years, between 2010 and 2015 in Romania were granted 45 titles: half to craftsmen (weavers, carpenters, iconographers, furriers, builders of musical instruments, pottery etc.) and half to performers of folklore (folk interpreter, rhapsodists, dancers etc.). Most distinctions, eight and seven, were awarded in Cluj and Alba county, followed by Brașov, Suceava county, each with five distinctions. Discussions are held about the possibilities of granting life annuity, following the model of athletes and some artists and writers. It is clear however that the title holders and their performance can be assimilated to tourism assets, as attractions of itself, transforming communities they belong to genuine tourist destinations. Furthermore, it would avoid the exhausting movements of artisans at the various trade fairs, being preferable to receive the audience in their personal household tranquility. A series of semi structured personal interviews with some LHT confirm this hypothesis. Strong promotion of those tourist destinations should no longer delay. At the central level it would require that the Tourism Authority take the „dossiers” for those LHT and promote them in a centralized manner, dedicating them an advertising brochure and a map

A straightforward x-ray on applying the ecolabel to the hotel business area

The ecolabel is a voluntary European initiative for certifying products and services. This study focuses on identifying the perception of persons benefiting of hotel services by designing a research and applying it to the clients of a hotel that acquired the license to use the ecolabel. Identifying the reaction of clients to the ecolabel and the manner it influences the purchase behavior as part of the objectives pursued, were implemented by drafting and applying a questionnaire to the clients of that hotel. Processing the acquired responses was made by the specific applications for data processing, the results confirming only in part the initial assumptions. At a general level, most clients believe that acquiring the ecolabel should be seen in prices, but most of them are unwilling to pay extra for hotel services holding this certificate. Considering that only three accommodation facilities hold this certification in Romania, the research we initiated can be the starting point for developing other more detailed studies concerning the opinion, reasons and purchase behavior of the clients

Perception About Business Education in the Tourism Domain and the Hospitality Industry

The research aimed at the importance of a well-structured business education, with a view to preparing the future employees for the requirements of the labour market, has become the central point in many key-sectors of the economy. This paper is based on having identified a gap in scientific research in Romania, that of the need to link the skills offered by the higher education system to the needs of the employers from the tourism and hospitality industry. Therefore, the following question arouses: „What is the perception of both employers and future employees on the training system for the tourism and hospitality industry domain?”. With a view towards obtaining an answer, the authors have chosen a descriptive type of research, i.e. a survey among students enrolled in the professional masters program Business Administration in Tourism, as well as among managers of representative hotels in Bucharest. The results show that the perception of students and professionals, respectively, are distributed comparatively, - on many aspects, such as the vocational character of the profession, the importance of attitude, of the theoretical and practical grounding -, but also that the profile of the graduate of an economic faculty of tourism, in the posture of candidate on the labour market, is quite controversial. Developing the curriculum, accordingly to the needs of the employers, will reduce the gap between the academic environment, as a supplier of professional formation, and the labour market, as a place where the labour force demand and supply meet

Multi-Response Optimization Analysis of the Milling Process of Asphalt Layer Based on the Numerical Evaluation of Cutting Regime Parameters

The present study aimed to optimize the process parameters (milling depth and advanced speed) for an asphalt milling operation using a multi-response approach based on Taguchi design of experiments (DOE) and Grey Relational Analysis (GRA). Nine simulations tests were conducted using Discrete Element Method (DEM) in order to determine the forces acting on the cutting tooth support and tip. The considered performance characteristics were cutting forces (smaller is better category) and chip section area (larger is better category). A Grey Relational Grade (GRG) was determined from GRA, allowing to identify the optimal parameter levels for the asphalt milling process with multiple performance characteristics. It was found that that the optimal milling parameters for multi-response analysis are a milling depth of 200 mm and an advanced speed of 30 mm/min. Furthermore, analysis of variance (ANOVA) was used to determine the most significant factor influencing the performance characteristics. The analysis results revealed that the dominant factor affecting the resultant cutting force was milling depth, while the main factor affecting chip section area was the advanced speed. Optimizing milling efficiency is essential in machining operations. A key factor in this direction is comprehending the interplay between chip removal and cutting forces. This understanding is fundamental for achieving increased productivity, cost-effectiveness, and extended tool lifespan during the milling process

Increasing the energy conversion efficiency for shrouded hydrokinetic turbines using experimental analysis on a scale model

The objective of the paper is to study the influence of certain shroud types suitable for horizontal axis hydrokinetic turbines using experimental testing in order to increase the energy conversion efficiency. The scale model of the shrouded hydrokinetic turbine is tested on a dedicated experimental bench for axial hydraulic turbine models. Two types of shrouds were tested in order to be compared: convergent shroud and divergent shroud. The rotor and shroud were made using 3D printer technology and were tested at a water velocity of 0.9 m/s on the closed-circuit testing bench. The testing facility allows the determination of the power extracted for each shroud at five distinct positions. Thus, the rotor can be moved within the shroud from inlet to outlet in order to establish the proper operating position. The mechanical power is measured using a torque transducer and an electromagnetic particle brake. The testing results will be analysed based on the variation of power curves obtained for different shroud types and operating positions. The optimum design and the best operating position will be recommended by comparing the testing result with the data collected from the bare turbine using the same rotor placed directly in free flow