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IMPACT OF ICT USE ON TIME STRUCTURE OF ADVISORS WORK AT THE LITHUANIAN AGRICULTURAL ADVISORY SERVICE 全文
2024
Stabingis, Linas
Information and communication technologies (ICT) already several decades is an integral part of business management and accounting data processing. Scientific publications most cases deal with increase the efficiency of calculations and information processing, improvement the quality of accounting information systems, but very little attention is paid to changes in the behaviour of accounting staff resulted by the implementation of modern information processing technologies. Scientific problem is the measuring of impact of the modern information and communication technologies on behaviour of advisors in accounting. Paper provides the results of theoretical analysis of impact, made by ICT on changes in registration and processing of accounting transactions and competences are necessary for accounting specialist. Empirical investigation bases on analysis of the data received during questioning consultants in accounting and economics, working at the Lithuanian Agricultural Advisory Service about the structure of working time allocated for various tasks and on changes in the structure of working time due to the use of ICT.
显示更多 [+] 显示较少 [-]SIMULATION OF MANAGEMENT ENHANCEMENT SCENARIOS FOR THE JSC LATVIAN STATE FORESTS 全文
2024
Feldmanis, Rolands | Pilvere, Irina
The expansion of global economy and the rise of living standards are set to force the world’s consumption of raw material to nearly double by 2060, thus consumption of wood resources is forecasted to increase more than twofold. In Latvia, forests cover 52% of the total area. The total forest area in Latvia has continued to grow since the beginning of the 20th century – in 1923 the forests covered only 27% of the country’s area; accordingly, the question is whether the value of forests continues to grow proportionally. One of the criteria for determining the value of forest is forest capital. A higher economic value of forest reflects the forest’s capability to produce more wood, and this allows generating higher revenues from forestry. It is the value of plantations of certain tree species as well as the quality of wood produced that increase the price of wood and consequently result in higher revenues. The largest supplier of wood in Latvia is the state-owned joint stock company Latvian State Forests (JSC LSF), which managed 1.6 million hectares of forestland in 2018. In 2018, 12.8 million cubic metres of roundwood were harvested in Latvia, of which 6 million cubic metres were harvested by the JSC LSF. Therefore, the research aims to design and assess potential scenarios of increasing the value of forest capital for the JSC LSF. The authors simulated potential scenarios for the JSC LSF in order to identify changes to be made in the current forest management pattern with the aim of increasing the value of forest capital. A higher value of forest capital would also mean greater public attention to the future use of existing resources. Calculations of the economic value of forests were carried out to identify necessary changes to be made in the management of state-owned forests in Latvia and to compare several management enhancement scenarios. The potential scenarios were assessed by five qualified experts, academics, representatives of business and public administration by employing the Analytic Hierarchy Process (AHP). The experts rated the possible scenarios for enhancing forest management relatively equally, giving slightly higher ratings to the potential scenario of quotation of the national forest management company on the stock exchange. The value of forest capital was calculated for each of the potential scenarios using the most commonly used net present value method (NPV). It was concluded that the potential scenario of lowering the diameter threshold for felling trees by two centimetres would lead to the greatest increase in the value of forest capital.
显示更多 [+] 显示较少 [-]EFFECTS OF DIFFERENT CLIMATIC CONDITIONS ON BIRCH AND POPLAR SEEDLINGS 全文
2024
Gudynaitė-Franckevičienė, Valda | Araminienė, Valda | Varnagirytė-Kabašinskienė, Iveta
The effects of different climatic conditions on birch (Betula pendula Roth) and poplar (Populus) hybrids seedlings were studied. This study consists of two parts, firstly, an experiment with poplars and, secondly, the experiment with birch seedlings. The aim of this study was to evaluate the growth of birch and poplar seedlings under the current and modelled climatic conditions. Results showed that the simulation of short-term warmer weather conditions and higher CO2 concentration led to more intensive growth of silver birch saplings. Different climatic conditions did not significantly change photosynthetic and transpiration rate of one year old silver birch seedlings. Contrary the transpiration and photosynthesis rate of poplar seedlings significantly depended on drought and clone but not on hybrid. Drought altered the transpiration and photosynthesis intensity, water use efficiency, and correlation among most of the traits. The P. maximowiczii × P. trichocarpa, P. balsamifera × P. trichocarpa hybrids increased their water use efficiency under the drought conditions and were characterized by faster growth hybrids. The sensitivity of poplar hybrids to UV-B radiation varied and depended on the origin of their parental trees: poplar hybrids from the northern latitudes were more sensitive to the increased UV-B radiation than those of southern origin. The best growth after simulated warm winter was obtained for the P. deltoides × P. nigra and P. nigra × P. nigra hybrids, originating from the southern areas. The findings from this experiment are more applicable to young birch and poplar trees, but stress on young trees may be reflected in future tree growth.
显示更多 [+] 显示较少 [-]MAIN DEFECTS AND DETERIORATIONS OF REINFORCED CONCRETE STRUCTURES IN THE ABANDONED HYDRAULIC STRUCTURES OF LITHUANIA 全文
2024
Šadzevičius, Raimondas | Skominas, Rytis | Sankauskienė, Tatjana | Ramukevičius, Dainius
Many abandoned (term "hostless" by 2010) hydraulic structures have been exploited for over 30 years, so due to the aging of materials, the probability of failures and accidents increases. Due to the insufficient exploitation in several dams the breakdowns occurred, some ponds in damaged dams have been emptied. It is known that no comprehensive research on technical state evaluation of abandoned hydraulic structures in Lithuania has been carried out. It becomes clear that practical, scientifically based algorithms for the technical state evaluation of abandoned hydraulic structures are needed in order to assess the impact of environmental factors on the technical state, safety, reliability and durability of structures. This paper focuses on the presentation of investigation results of technical state evaluation of 4 abandoned hydroschemes in Raseiniai distr. Due to the noticed significant defects and deteriorations all 4 hydroschemes are in critical state, the pond in Gyliai IV is emptied, the demolition of reinforced concrete structures should be applied in this object.
显示更多 [+] 显示较少 [-]MASTERING AGTECH AGAIN: EMERGING OF NEW TRAINING OFFERS AND INTERMEDIATE PLAYERS 全文
2024
Rizzo, Davide | Ritz, Simon | Combaud, Anne
Agricultural machinery manufacturers historically referred to the intermediate players for selling, maintenance, customer service and/or training of equipment appear to interact with farmers and end-users. Intermediate players have therefore faced the burden to master the technology, in constant evolution, and the associated training needs at the interface between a sophisticated equipment and the end-user and its sociological characteristics (age, education, background, etc.). However, the effective deployment of agricultural technologies data augmented equipment demands well trained players. How to ensure that the intermediate players have the required skills to integrate the use of agtech in the farm? This paper will discuss the role of educational and ongoing vocational training for the mastery of agtech. We will start from a comparative review of some key national and European technical reports in the agricultural equipment and innovation domains. On these bases, we will focus on France to describe the role of intermediate players of the agricultural equipment sector to realize their agricultural and digital transitions.
显示更多 [+] 显示较少 [-]BIODEGRADABLE CHELANTS FOR HEAVY METAL REMOVAL FROM SLUDGE AND SOIL-SLUDGE MIXTURES 全文
2024
Paulauskas, Valdas | Zaleckas, Ernestas | Karnaukh, Oleksandr
Heavy metal extraction study was performed using five chelating agents with different biodegradability: EDTA, EDDS, MGDA, SCLC and citric acid. Aminopolycarboxylic acids EDDS and MGDA showed high heavy metal extraction capability from sewage sludge and sludge-soil mixtures. According to heavy metal removal efficiency investigated chelants can be ranked in the following order: EDTA≈ EDDS≈ MGDA> CA> SCLC. Extraction efficiency from sludge mixtures with clay soil was markedly lower than from the mixtures with sandy soil. Biodegradability of EDTA, MGDA, EDDS and CA was evaluated measuring BOD in water environment over 28 day period. According to the results of biodegradability test after 28 days the ranking order of the chelants was following: EDDS (99%)> CA (32.4%)> MGDA (29.2%)> EDTA (14.9%). Results showed that significantly easier than EDTA biodegradable chelating agents, such as EDDS and MGDA, can be successfully used for heavy metal removal from sewage sludge as well as metal-contaminated soil.
显示更多 [+] 显示较少 [-]METHOD OF DESIGNING FUZZY SYSTEM FOR PLANNING ROBOT MANIPULATOR REAL-TIME MOVEMENT IN A STATIC ENVIRONMENT: Method of designing fuzzy system for planning robot manipulator real-time movement in a static environment 全文
2024
Nemeikšytė, Daiva | Osadčuks, Vitalijs
Under rapid development of science and industry the industrial robots and robotic systems are more widely used in the field of industry. The robots and robotic systems help to manage and master new technological processes efficiently and effectively. In this article there was carried out the analysis of the two degree of freedom (DOF) robot arm, which is widely used in practice in order to reveal its functions and to identify its key dynamic parameters using fuzzy logic system. The mathematical model of robot arm dynamics is composed, which includes the mathematical models of the robot arm links twirling motors and the direct positions task model generating the end point of the robot. After the analysis of the robot model the expanded research was performed – after calculating the missing parameters of experimental 2DOF robot arm motors there was created the robot arm model with „V-REP“ and “MATLAB Simulink” software packages that allowed to set the control voltages and to observe the changing in time processes of link velocity trajectories. There is calculated designed planar robot end point trajectory deviation from the dynamic trajectory.
显示更多 [+] 显示较少 [-]POP-UP RURAL SOCIALLY-INNOVATIVE HUBS – CASE STUDY FROM CROATIA 全文
2024
Kantar, Sandra | Svržnjak, Kristina
This paper presents formation of the first pop-up rural socially-innovative hubs in Croatia through the cooperation of higher education institutions, civil society organizations, students, alumni and local people in the specific rural communities of Međimurje and Split-Dalmatia County. The main purpose of the hubs is to develop, test and validate an inclusive and participative program of service learning in the field of sustainable rural development. Pop-up rural hubs are mobile model of service learning that functions as an occasional event in the local community, to which all interested initiators are invited to join. From the sociological perspective, the most important aim of this project is to strenghten rural local communities through the launch of socio-innovative sustainable micro-entrepreneurial activities by using local resources. Through pop-up rural hubs, business ideas and plans are tested, and through additional mentoring and business plan, initiators were able to send the product or service on the market. Although the project is not over yet, the preliminary results show that pop-up rural socially-innovative hubs, within a period of one year project duration, stress the differencies and similarities between local communities in different parts of rural Croatia, enhance human capital and have a social impact on higher education institutions, civil society organizations, students, alumni and local people.
显示更多 [+] 显示较少 [-]THE RESEARCH WAYS TO INCREASE THE ENERGY EFFICIENCY OF GROUND HEAT EXCHANGERS BY MEANS OF MATHEMATICAL SIMULATION 全文
2024
Mikhailutsa, Olena | Koviazin, Oleksiy | Pozhuyev, Andriy | Poliakova, Nataliia | Melikhova, Tatiana
The scientific and methodological basis for increasing the efficiency of geothermal ventilation, making it possible to use thermal energy of the Earth’s surface layers for cooling (heating) an incoming air stream are created. Mathematical modeling is performed based on the equations of hydrodynamics, heat transfer and thermal conductivity, along with a computational experiment carried out using the finite volume method. A mathematical model of the process of heat exchange between the flow of air in a heat exchanger and a soil mass is developed. This model describes a relationship between efficiency indicators of the horizontal ground heat exchanger and its performance parameters, and also natural climatic conditions. The determination of thermal fields in incoming cooled air and a soil mass at various depth locations of the horizontal ground heat exchanger is performed. The relationship between thermal efficiency and operation time of the horizontal heat exchanger, located at different depths, is proved. The energy comparison of a horizontal ground heat exchanger, located at different depths, with a vertical one, is made. he depth of the horizontal heat exchanger has been established, for which the loss of thermal energy in comparison with the vertical is insignificant (less than 7.5%). The operating time was determined, starting from which there are practically no differences in the level of thermal energy for all the studied models (> 107 s). The developed mathematical model allows to predict the energy efficiency indicators of a horizontal ground heat exchanger on the basis of its performance parameters and natural climatic conditions, that makes possible determining the economically optimal depth of the heat exchanger location under specific conditions.
显示更多 [+] 显示较少 [-]TECHNOLOGICAL DESCRIPTION FOR AUTOMATING THE CULTIVATION OF BLUEBERRIES IN BLUEBERRY PLANTATIONS ESTABLISHED ON DEPLETED PEAT MILLING FIELDS 全文
2024
Arak, Margus | Olt, Jüri
In order to increase the cost-effectiveness of blueberry (Vaccinium) cultivation in blueberry plantations, all of its technological operations should be automatized. It is reasonable to start the automation of blueberry cultivation from the technological operation of fertilising the blueberries as the main purpose of this operation is to dose a prescribed amount of fertiliser under the plant’s crown. When a new blueberry plantation is established on depleted peat milling fields, then the plants are set at pre-determined steps into parallel rows. Fertilisation of the plants in the first years of growth must be performed individually, i.e. each plant is fertilised separately. This is called precision fertilisation. In order to design the technological devices for blueberry cultivation, including the fertiliser robot, we must know the location of plants on the field or, more precisely, their position in the row. The goal of this study is to determine the position of blueberry plants in the plantation. In order to meet the goal, measurements were performed in the blueberry plantation and the position of plants in randomly chosen row was measured. It became clear from the study that plants are not positioned regularly at equal intervals in a straight line; therefore, the fertiliser robot to be designed must include the functions of plant identification and control of fertiliser jet to ensure individual or precision fertilisation of plants.
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