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Improving the designing of mechanical technologies through optimized dimensional structures
Get PDFModern trends in technological development related to the use of numerical control machine tools are manifested by minimizing the number of technological operations, installations, operation elements. One of the most effective ways to improve the design of mechanical processing technologies is to create optimal technological dimensional structures. In the paper, optimality requirements are formulated in relation to the elementary dimensional structures and the entire structure. It is shown that a technological dimensional structure is optimal if it is similar to the constructive dimensional structure. Real constructive dimensional structures are very complex and varied, so that the optimality of some sequences of the structure excludes ensuring the optimality of other sequences. Reciprocal structural adaptations are required, which can be done by constructively resizing the equivalent part. As a criterion for the resizing, the non-admission of the increase in the tolerance of the machining allowance is manifested
PROCESSING OF VIBRO - ACOUSTIC SIGNALS OF PRECESSIONAL PLANETARY TRANSMISSIONS
Get PDFThe operation of working machines is accompanied by the constant occurrence of vibrations and shocks, generated by various constructive, kinematic and dynamic factors. The study of the vibro-acoustic aspect of mechanical transmissions and, in particular, of precessional planetary ones is a primary concern for engineers in the field of machine building technologies. The paper presents the research of precessional planetary transmissions under the vibro-acoustic aspect in the anechoic chamber, which is a room, insulated with sound-absorbing material against external noises and isolated anti-vibration. To process the vibro-acoustic signals received as a result of the measurements, the Fourier harmonic series will be applied, a mathematical function that can be used to find the basic frequencies that make up a wave. The final result is the detection of vibration and noise generating sources, the decoding of signals by means of Fourier series and the advancement of constructive-technological solutions to minimize the vibro-acoustic level
National and international experience regarding development of bicycle infrastructure
Get PDFCyclists, together with pedestrians, as traffic participants, are the most vulnerable. Every year in the world over 40000 cyclists die on the roads, which represents approximately 3% of the number of people who died in road accidents. Ensuring the safety, including of these road users, must be part of the basic priorities of any country.The development of bicycle infrastructure brings social, economic and ecological benefits. The article presents a brief description and analysis of state programs in some countries and in Republic of Moldova (the city of Chisinau) regarding the development of cycling in urban road traffic
A new concept regarding the selection of sewerage systems and natural treatment of municipal wastewaters
Get PDFThe article contains a review of methods and procedures of the municipal wastewater treatment, with the discussion of their specifics. A new concept is proposed related to the selection of municipal sewerage and wastewater treatment systems, considering the local/decentralized, semicentralized or centralized systems, especially those suitable to rural and suburban localities, in dependence on the advantages and disadvantages of these systems and local specifics. The concept of phytofilters is proposed for the biological treatment of wastewater in small towns. This technology is simple, inexpensive and requires relatively little maintenance. Biological ponds in the Republic of Moldova have proven to be very suitable for advanced wastewater treatment, being a cheap and natural purification system with a good potential for implementation. When choosing a sewer system, priority must be given to its functionality and practical considerations
THE INFLUENCE OF THE HEATING AGENT TEMPERATURE ON THE KINETICS OF THE CONVECTIVE DRYING PROCESS AND THE CONTENT OF BIOACTIVE COMPOUNDS IN APPLE POMACE
Get PDFAn environmentally ecological approach to the reuse of agro-industrial products in the food industry involves extracting biologically active substances or using them as supplementary products rich in dietary fibers. Apple pomace obtained after juice extraction presents a product rich in biologically active substances, soluble and insoluble fibers, organic acids, and minerals. Convective drying of apple pomace is an alternative method for long-term preservation by maintaining the biologically active substances. The research aimed to study the influence of temperature in the range of 60-80 °C on the drying of apple pomace to a final moisture content of 12.0±0.13% using the convective method, and the effect of temperature on the yield of bioactive compounds and antioxidant activity in Gold Delicious apple pomace. Changing the air temperature during convective drying from 60 to 80 °C reduced the drying time by 1.6 times and demonstrated a 1.4-fold increase in drying rate. The increase in the thermal agent's temperature led to an increase in the kinetic characteristic values; KI values increased by 4%, and KII values increased by 44%. Spectrophotometric analysis demonstrated that apple pomace dried at a temperature of 70 °C had the highest total content of polyphenols, tannins, and carotenoids. Thus, the convective drying method of apple pomace in the temperature range of 60-80 °C exerts a significant influence on the composition of biologically active compounds in the apple pomace composition
Interior design in the renovation, modernization and aesthetic editing of the Museum of History and Ethnography in Ungheni
Get PDFThe present paper deals with a scientific analysis of the interior design within the licensing process concerned with the renovation, modernization and aesthetic editing of the Museum of History and Ethnography in Ungheni, carried out in 2022. In the context, the historical course of formation and evolution of the museum is described, prominent personalities who contributed to the development of the museum, museum pieces and categories of exhibits in the museum's possession. All these have been used in value through the vision of interior design which is researched through the historical, ethnographic and artistic prism. Through the research, the role and responsibility of interior design in the process of consolidation and valorization of the national cultural heritage is highlighted. The given study presents the result of the interior design project, concerned with the correspondence or synchronization of the new modern implementations with the ethnographic data inherited from the historical period
INCENTIVES AND DISINCENTIVES IMPACT ON MANAGERIAL COMMUNICATION - A SYSTEMIC-CYBERNETIC TREATMENT
Get PDFThe purpose of this article is to research the issue of managerial communication, being a part of a complex and larger research related to the impact of managerial communication on the development of small and medium-sized enterprises in the Republic of Moldova, having as the object of research the SMEs in the wine sector. One of the many concerns of a modern manager is improving managerial performance. In the daily challenge, they have to better achieve the proposed objectives, and the set tasks - to have better results, to form a stronger team and a more favourable organisational climate in the enterprise, to ensure better results, the manager can succeed even by improving internal managerial communication. Through internal managerial communication, the manager not only transmits and receives information from subordinates, but establishes constructive relationships with them and forms an organizational climate favourable to the growth and development of the company's performance. The organizational climate in the enterprise, as an inclusive result of the managerial communication style, can be defensive or cooperative, the specifics of these types of organizational climate being analysed in the respective article. The present article comes with a scientific novelty and more precisely a systemic-cybernetic perspective on the problem of subordinates' reaction to incentives and disincentives in managerial communication. At the same time, it is demonstrated the probability of balance of success in achieving tasks and objectives proposed to subordinates by the manager, to achieve the desired results depending on the use of incentives and disincentives in internal managerial communication
ANALYSIS AND IMPACT OF APIA ACTIVITY ON DEVELOPMENT AND SUPPORT OF AGRICULTURAL SECTOR IN ROMANIA
Get PDFAgriculture is a very important sector for Romania, providing food and products of vegetable and animal origin, jobs for people in villages and business opportunities for enterprises and investors. Romania's agricultural area is in permanent change, influenced by European money that was attracted through support measures and community policies, and environmental protection and the need to ensure a sustainable development of agriculture in Romania made the activity of the Agency for Payments and Intervention for Agriculture (APIA) stands out as an important factor in aligning modern agriculture with the environment. Through this study, we aim to analyze the way in which APIA promotes sustainable agricultural practices and provides support to farmers to protect the environment and whether the agency's activity has brought benefits to the economic development of Romania and Neamț County. We thus demonstrate the important role that the agency has for the economy, for supporting farmers and agricultural producers in Romania, but also for the country's agricultural policy, the institution participating in the development and implementation of national agricultural policies and strategies, as well as in the process of negotiating subsidies and projects within the European Union (EU) agricultural financing system
Rolul inciziilor la formarea coroanei prin garnisirea axului pomilor de cireș din soiul Grace star pe portaltoiul Gisela 6
Get PDFThe study was carried out in a cherry plantation established in the spring of 2020 in the north of the country. The object of the research was the variety Grace Star at 4.2x1.8 m spacing and grafted on the rootstock Gisela 6. In order to study different secondary technical operations in cherry cultivation, an experiment was organized in spring 2021 with the following gradation: 1. Trees trained as a slender spindle (control); 2. Solitary incision above the buds and treatment of the cut with water; 3. Solitary incision above the buds and treatment of the cut with the growth regulator Progerbalin LG; 4. Circular incisions on the leader at 25-30 cm from each other and treatment of the cut with Progerbalin LG growth regulator; 5. Extirpation of 4-5 axillary buds from top to bottom of the leader while keeping a bud intact. Tree parameters, the number of branches, average and summed branch length, leaf area, branching angle of branches, the number of solitary flower buds and bunches of may were studied during the research. It was established that to increase the branching potential of the leader, when training cherry trees, solitary incisions above the buds and circular incisions at a distance of 25-30 cm on the leader should be applied and treatments of the cut should be performed with the growth regulator Progerbalin LG in the ratio one part of product to 8-10 parts of latex paint
Влияние регуляторов роста растений на формирование эмбриональной плодоносности почек зимующих глазков по длине однолетнего вызревшего побега технического сорта винограда Бианка
Get PDFThe influence of the plant growth regulators gibberellin and mycephyt on the embryonic inflorescence initiation along the length of the annual shoot of the Bianca grape variety, taking into account the climatic conditions of the year, was the purpose of our research. A treatment of plants was carried out before flowering with gibberellin at a concentration of 100 mg/l and mycephyt at three concentrations of 1, 10 and 100 mg/l. Fruiting coefficient and fruitfulness coefficient of the central buds of overwintering compound buds (eyes) along the length of the annual shoot were calculated, as well as the portion of fruitful eyes with 2-3 embryonic inflorescences was determined based on the obtained results.It was established that the treatment of plants with gibberellin stimulated the initiation of embryonic inflorescences at the level of the 7th node, which exceeds the control by 1,4 times. An increase in the portion of embryonic inflorescences at the level of the 2nd, 4th and 7th nodes by 12,8, 31,0 and 15,3 % was detected in comparison with the control when using mycephyt at a concentration of 1 mg/l. Also, an increase in the fruitfulness coefficient (ratio of the number of embryonic inflorescences to the number of fruitful eyes) at the level of the 7th node (1,77), which is 1,2 times higher than the control (1,46) in mychephyt (1 mg/l) treatment version was noted. The maximum value of fruitfulness coefficient was established in gibberellin and mycephyt (1 mg/l) treatment versions at the level of 8-10th (1,71) and 4-7th node (1,47), accordingly