Utjecaj projektnih parametara uređaja za horizontalno cijepanje drva na silu cijepanja

The article deals with the influence of the shape of the splitting wedge on the size and course of splitting force. Today maximum effort is made to search for and use of energy saving solutions in every industry. Such solutions can include a change of the form of the longitudinal splitting wedge for splitting logs. The core of this problem is the experimental detection of powers, followed by analising the individual effects. For this purpose, an experimental device was designed. The base of equipment consists of a mobile horizontal splitter, which is well adapted to capture the process of splitting force in splitting logs. According to the results, the type of wood was the most influencal factor, followed by wood diameter and splitting wedge. When comparing the average values that were generated from repeated measurements, it is possible to follow the reduction of splitting force. The results showed that the splitting force was reduced by approximately 13 % when comparing splitting wedge No. 1 (simple) and No. 2 (refracted). When comparing splitting wedges No. 1 (simple) and No. 3 (concave), it can be observed that the splitting force was reduced by more than 50 %. The experiment also confirmed the effect of different anatomical structures of different species of wood on various physical and mechanical properties of such wood and hence also on the splitting force in splitting wood.U članku se govori o utjecaju oblika klina za cijepanje drva na veličinu i smjer sile cijepanja. U današnje vrijeme ulažu se veliki napori u pronalaženje i primjenu novih riješenja za uštedu energije u svim industrijama. Jedno od takvih rješenja može predviđati i promjenu oblika klina za uzdužno cijepanje trupaca. Za taj problem važno je eksperimentalno odrediti snagu te analizirati pojedinačne utjecajne parametre. Za tu svrhu izrađen je eksperimentalni uređaj za cijepanje drva. Baza opreme sastoji se od mobilnoga horizontalnog razdjelnika, koji je dobro prilagođen praćenju procesa cijepanja i sile za cijepanje trupaca. Rezultati su pokazali da najveći utjecaj na silu cijepanja ima vrsta drva, zatim promjer drva i, na kraju, oblik klina za cijepanje. Usporedbom prosječnih vrijednosti dobivenih ponovljenim mjerenjima može se pratiti smanjenje sile cijepanja. Rezultati su pokazali smanjenje sile cijepanja za oko 13 % ako usporedimo cijepanje uz pomoć klina 1 (jednostavni) i klina 2 (slomljeni). Usporedimo li klinove za cijepanje broj 1 (jednostavni) i broj 3 (konkavni), može se uočiti smanjenje sile cijepanja za više od 50 %. Eksperiment je također potvrdio utjecaj anatomske građe različitih vrsta drva na fizikalna i mehanička svojstva drva, a time i na silu cijepanja pri obradi drva cijepanjem

Information technology for intellectual analysis of item descriptions in e-commerce

E-commerce is experiencing a robust surge, propelled by the worldwide digital transformation and the mutual advantages accrued by both consumers and merchants. The integration of information technologies has markedly augmented the efficacy of digital enterprise, ushering in novel prospects and shaping innovative business paradigms. Nonetheless, adopting information technology is concomitant with risks, notably concerning safeguarding personal data. This substantiates the significance of research within the domain of artificial intelligence for e-commerce, with particular emphasis on the realm of recommender systems. This paper is dedicated to the discourse surrounding the construction of information technology tailored for processing textual descriptions pertaining to commodities within the e-commerce landscape. Through a qualitative analysis, we elucidate factors that mitigate the risks inherent in unauthorized data access. The cardinal insight discerned is that the apt utilization of product matching technologies empowers the formulation of recommendations devoid of entailing customers' personal data or vendors' proprietary information. A meticulously devised structural model of this information technology is proffered, delineating the principal functional components essential for processing textual data found within electronic trading platforms. Central to our exposition is the exploration of the product comparison predicated on textual depictions. The resolution of this challenge stands to enhance the efficiency of product searches and facilitate product juxtaposition and categorization. The prospective implementation of the propounded information technology, either in its entirety or through its constituent elements, augurs well for sellers, enabling them to improve a pricing strategy and heightened responsiveness to market sales trends. Concurrently, it streamlines the procurement journey for buyers by expediting the identification of requisite goods within the intricate milieu of e-commerce platforms

Špecifické aspekty spracovania geodetických sietí použitím programu SoNet

Článok je zameraný na popis programu na spracovanie geodetických sietí s analyticky definovanýmm matematickým modelom (observačné rovnice definované v programe v symbolickom tvare), čo je najvýraznejšia črta, ktorou sa program odlišuje od súčasných programov na spracovanie geodetických sietí.Univerzálnost’ programu demonštrujeme na príklade spracovania viacepochovej geodetickej siete. Spracovanie bolo uskutočnené vo forme prípadových štúdií od elementárnej kombinácie meraní GPS s uvážením kovariančných matíc, až po spoločné spracovanie terestrických observácí a GPS s uvážením časových zmien a transformačných parametrov v spoločnom matematickom modeli.</p

Presné určovanie absolútnej polohy pomocou globálnych družicových navigačných systémov - súčasné možnosti, obmedzenia a perspektívy =Precise point positioning using global navigation satellite systems - present-day potential, limitations and perspectives

Principles of Precise Point Positioning using code and phase GNSS observations. Mathematical model, correction of systematic biases, main steps of measurements processing. An example of demonstration of the method using the GPS observations. Discussion about perspectives of the method of Precise Point Positioning20921

Wood Crosscutting Process Analysis for Circular Saws

This article deals with the influence of some cutting parameters (geometry of cutting edge, wood species, and circular saw type) and cutting conditions on the wood crosscutting process carried out with circular saws. The establishment of torque values and feeding power for the crosswise wood cutting process has significant implications for designers of crosscutting lines. The conditions of the experiments are similar to the working conditions of real machines, and the results of individual experiments can be compared with the results obtained via similar experimental workstations. Knowledge of the wood crosscutting process, as well as the choice of suitable cutting conditions and tools could decrease wood production costs and save energy. Changing circular saw type was found to have the biggest influence on cutting power of all factors tested

UKRAINOS ŽEMĖS IŠTEKLIŲ EROZIJOS DINAMIKOS VERTINIMAS

Soils are considered as the main and most powerful in the territorial plane component of the environment. In agriculture, productivity largely depends on the soil condition. Due to excessive tillage, deficit balance of humus and nutrients, lack of organic matter and mineral fertilizers, chemical meliorants, pollution, soil Ukraine under current conditions continues to degrade. On the decline of soil fertility also shows a negative balance of humus and nutrients. The problem protection of land, the struggle against degradation now rose to the level of major, global. To protect land measures in regions of Ukraine is very actual in our time.&nbsp; The purpose: analysis of changes in the state of Ukraine land resources for recent years, estimation the processes of droughts and desertification, that generate water and wind erosion, which causes degradation of soil fertility and reduces the productivity of agroecosystems. Methodology: for determining the sources of the negative processes of water and wind erosion, used comparisons and analysis of statistical data for recent years by choosing the main agrosystem parameters. In the article used a structural analysis, based on the dynamics of the distribution of Ukraine land resources for the estimation of economic use by using the coefficients of economic stability and anthropogenic load. Findings. Due to the large-scale intensification of agriculture production, the land area with various types of degradation has increased significantly. Factors, that deterioration of land quality, and hence increase their degradation, are excessive moisturizing, waterlogging, salinity, acidification, deflation, water erosion, and alkalization. To prevention the process of soil degradation and economic losses, to improving the environment as a whole, it is necessary to realize the complex measures of ecologization of agriculture. &nbsp;Žemės ūkyje produktyvumas labai priklauso nuo dirvožemio būklės. Dėl per didelio žemės dirbimo, humuso ir maistinių medžiagų deficito, organinių medžiagų ir mineralinių trąšų trūkumo, cheminių meliorantų, taršos, dirvožemis Ukraina dabartinėmis sąlygomis ir toliau blogėja. Mažėjant dirvožemio derlingumui, taip pat pastebimas neigiamas humuso ir maistinių medžiagų balansas. Probleminė žemės apsauga, kova su degradacija dabar pakilo į pagrindinį, globalų, lygį. Mūsų laikais labai aktualu apsaugoti sausumos priemones Ukrainos regionuose. Tikslas: pastarųjų metų Ukrainos žemės išteklių pokyčių analizė, sausrų ir dykumėjimo procesų, sukeliančių vandens ir vėjo eroziją, sukelianti dirvožemio derlingumo blogėjimą ir mažinanti agroekosistemų produktyvumą, įvertinimas. Metodika: neigiamiems vandens ir vėjo erozijos procesų šaltiniams nustatyti, naudoti paskutinių metų statistinių duomenų palyginimai ir analizė, pasirenkant pagrindinius agrosistemos parametrus. Straipsnyje naudota struktūrinė analizė, pagrįsta Ukrainos žemės išteklių pasiskirstymo dinamika, siekiant įvertinti ekonominį naudojimą, naudojant ekonominio stabilumo ir antropogeninės apkrovos koeficientus. Išvados. Dėl didelio masto žemės ūkio gamybos suintensyvėjimo labai padidėjo žemės plotas su įvairiais degradacijos būdais. Veiksniai, dėl kurių blogėja žemės kokybė ir dėl to padidėja jų blogėjimas, yra per didelis drėkinimas, vandens nutekėjimas, druskingumas, rūgštėjimas, defliacija, vandens erozija ir šarminimas. Norint užkirsti kelią dirvožemio degradacijai ir ekonominiams nuostoliams, pagerinti aplinką kaip visumą, būtina įgyvendinti sudėtingas žemės ūkio ekologijos priemones

Testing of Cutting Tools on a Pneumatic Experimental Device and Evaluation of Cutting Edge Wear Using a Non-Contact 3D Method

This research is focused on the evaluation of cutting edge wear of the delimbing knife by contactless methods. Delimbing knives were tested in an experimental device constructed in our laboratory, which operates on the principle of a forest harvester head. The greatest wear of the cutting edge was manifested in knife no. 1 with a blade angle of ∢ 7°. The research was focused on the wear of delimbing knives made of DIN 58SiCr8/WNr material when changing the angular geometry of the tool and using a constant delimbing speed of 2.0 m.s−1 while delimbing spruce wood of various wood diameters. The Alicona Infinite Focus device, which functions as a non-contact 3D optical device, was used to determine the amount of wear on the cutting edge of the knife. The size of cutting edge wear significantly affects chipless cutting wood, which can be observed in an increase in the cutting force during the delimbing process. The use of harvester technology in forestry is a highly topical issue today. From this point of view, it is necessary to focus on increasing the efficiency and reducing the energy consumption of the machine, which economically benefits its delimbing operation