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- Publication3D SCANNERS. DIVERSITY AND OPERATING PRINCIPLES(2017)
;Aksjonovs, Artēmijs; Martinovs, AndrisThe paper deals with existing 3D scanners classification and types. Each 3D scanner given the principle of operation. It examines the scope of application of different type scanners advantages and disadvantages. The aim was based on this data to create a 3D scanner prototype, by means of which an ordinary user can conveniently and easily scan a small, straightforward form objects. - PublicationANALYSIS OF CONTACTLESS RADIO FREQUENCY IDENTIFICATION TECHNOLOGIES AND ITS USAGE IN REZEKNE CITY INFRASTRUCTURE OBJECTS(2016-04-20)
;Zalužinskis, ArtūrsAuthor made the analysis of usage of contactless radio frequency identification technologies in Rezekne city infrastructure objects. Author provides the main types of radio frequency hardware, working principles and worldwide usage statistics. In the conclusion of the paper, author describes the further development opportunities of the radio frequency identification technologies. - PublicationAS „OLAINFARM” SEWAGE TREATMENT PLANT EFFICIENCY IMPROVEMENT(2017)
;Grisone, AgneseResearched the problem is that during the manufacturing process mother liquor is fed to the sewers. Then the mother liquors into the biological treatment plant. Results and evaluation are reflected in the input and output samples of waste water results in which the sample results are not following the requirements laid down. Wastewater treatment plants have been built a long time ago and need to supplement existing equipment to clean up the quality of untreated wastewater. - PublicationASSESSMENT OF THE ENVIRONMENTAL ELEMENTS PERFOMANCE EFFECTIVENESS IN LAND DRAINAGE SYSTEMS(2018)
;Lomanovska, InitaViena no būtiskākajām problēmām saistībā ar ūdeņiem ir eitrofikācija. Eitrofikācija ir ūdens avotu pastiprināta aizaugšana. Lai samazinātu eitrofikācijas procesus ūdensnotekās izbūvē videi draudzīgus meliorācijas elementus: sedimentācijas baseinu, akmens krāvumu, divpakāpju meliorācijas grāvjus, meandrēšanu, kontrolēto drenāžu, mākslīgos mitrājus [5].Pēc videi draudzīgo meliorācijas elementu izveides, ūdensnotekā palielinās uzkrātās augu barības vielas, tāpēc ir jānodrošina to tālākais apsaimniekošanas process [2]. Raksts satur informāciju par Latgales reģionā pielietotajiem vides elementiem. Tiek veikta informācijas apkopošana, analīze un izvērtēšana par vides elementu efektivitāti. Sniegti priekšlikumi par veids elementu izbūvi un priekšrocībām. - PublicationCARBON DIOXIDE (CO2) LASER MARKING PROCESS PARAMETER IMPACT ON MARK QUALITY OF POLIVINILCHLORIDE (PVC) MATERIAL(2017-04-19)
;Riekstiņš, Jānis ;Sivenkovs, Artūrs; Narica, PāvelsLaser technologies nowadays are widely used in material processing. CO2 laser systems in most cases are used in metallic material manufacturing and processing, taking not so big part in processing of plastic materials. This research is dedicated to find advantages or disadvantages and ways to use CO2 laser systems in plastic material processing, by taking PVC material as sample for experiments. PVC plastics is widely used in manufacturing of electrical installation details and devices, it is durable, relatively light, and cheap material. To provide application of various symbols, on the surface of plastic materials, can be used laser systems, which in long term can be more efficient than conventional marking methods. The aim of this work is to find if CO2 laser is appropriate for marking PVC material and to relate the mark quality parameters and the marking process parameters. The research was conducted in the period of time from March 2017 till April 2017, in the Rēzekne Academy of Technology, Physical process and laser technology research center. - PublicationCARBON FIBER AND PLANT FIBER COMPOSITE TECHNOLOGY DEVELOPMENT IN HIGH STRENGH PARTS(2017)
; Natural abundance, low density, high strength per unit weight, and biodegradability of natural materials, specifically natural fibres, render them attractive for other reinforcements. In order to clarify the effect of natural fibers as reinforcments upon the tensile strength of polyacrylonitrile (PAN)-based carbon fibres, experimental as well as theoretical studies have been performed. A new material developing has been made in combining different fiber materials and testing them for strengh. - PublicationCLEANED WATER QUALITY IN THE EXPERIMENTAL CIRCUIT LABORATORY(2016)
;Grisone, AgneseFor the moment there is no problem, because the clean water complies with the following requirements. But it is the nature of the mechanical problems, where technical and cleaned water in the production process increased conductivity indicators and the pH value is less than the soft water after legislative dossier. Materials and methods are described in the clean water sampling physical – chemical testing, as well as describes the methods used. And you are prompted to create the electricity supply system, which, in addition to the accidental or unplanned power off position. It will depend on the results of a number of indicators. You can view a version of the technology, if not improving, the ability to create an automatic power supply system. - PublicationCONSOLIDATED FINANCIAL STATEMENTS AS THE BASIS OF RELIABLE INFORMATION ON THE ACTIVITY OF INTEGRATED CORPORATE STRUCTURES OF UKRAINE(2017-12-28)
;Aija CerpinskaTetyana YakymchukThe research presents an algorithm for comparative analysis of the integrated corporate structure reporting including three stages. The proposed algorithm for comparative analysis has been tested on the example of the consolidated financial statements of sub-holding of the industrial and financial group, the financial statements of one of the main asset parent companies in Ukraine and a subsidiary of the sub-holding. It has been established that users cannot make proper conclusions and take decisions in a comprehensive way basing upon information provided in public financial reports. - PublicationDETERMINATION OF WATER POLLUTION USING SATELLITE DATA(2017)
;Kaļva, LilitaOne of the major eutrophication - causing substances are all elements - phosphorus and nitrogen, which enters the surface water from agricultural areas, sewage treatment plants and other sources. Therefore, the more attention focused on the nutrient elements –phosphorus and nitrogen effects on algal growth and weight gain. In Rezekne Technology academy laboratory experiments were carried out under laboratory conditions, the algae, grown in weight gain, depending on the water temperature and nutrient concentration. Lake Burtnieks is analyzed with satellite data. The results shows that satellite data can be used for remote monitoring of bodies of water quality change and water quality forecasting. - PublicationENERGY EFFICIENCY IMPROVEMENT PLAN(2018)
;Matulis, JānisAs climate change issues and increasing CO2 emissions are rising, "green energy" or renewable energy sources include solar, wind power, biomass, geothermal energy, etc. One of the most important sectors of the economy is energy. Its main tasks are energy recovery, its processing in all types of energy and delivery to consumers. No energy development is possible without the development of any economic sector. Energy is mainly used for energy production - PublicationFACTORS AFFECTING CEREAL GROWTH IN A FARM RATNIEKI(2018)
;Sprinģe, ZaigaCrop production is the most important crop production, since grain production contributes to the economic and political stability of any country, and the well-being of its citizens. The scientific paper summarizes information on the soil's chemical properties. Performed soil samples of the farm "Ratinieki" in the amount of soil, pH and electrical conductivity analysis of soil. On the basis of the research carried out, conclusions were made on the conditions of cereal cultivation on the holding. - PublicationFOREST QUALITY RESEARCH IN MALTA MUNICIPALITY(2018)
;Šembele, InaThe scientific article contains information about forest stands in the territory of the Malta parish. In the field studies in the plots, the quality of black alder, birch, pine and fir trees has been assessed according to the height, the average, basement area and the number of trees in the plot, and the tree stock is estimated. In general, the quality of forests in the territory of the Malta parish is considered to be good. Problems were detected in the furrows, since after removing the part of valuable materials, the furrows have left branches that are a place of pest control and a potential threat to forest stands. Areas without forest restoration were found. - PublicationGaisa enerģētiskā stāvokļa ietekme uz pilsētu infrastruktūru(2010)
;Skromulis, AGrigorjeva, JRakstā aktualizēta atmosfēras gaisa kvalitātes problēma, īsumā raksturotas gaisu piesārņojošās ķīmiskās, mehāniskās un enerģētiskās komponentes, īpašu uzmanību pievēršot gaisa enerģētiskajam stāvoklim kā savdabīgam gaisa kvalitātes indikatoram. Rakstā sniegts ieskats pozitīvo un negatīvo aerojonu klasifikācijā un struktūrā. Īsumā izklāstīta gaisa jonizācijas teorijas būtība un jonizācijas ietekme uz dabas vides abiotisko un biotisko komponenti, īpašu uzmanību pievēršot pozitīvo un negatīvo vieglo aerojonu fizioloģiskajai ietekmei uz cilvēka organismu. Tajā atspoguļoti Rēzeknes pilsētas dažādos mikrorajonos veiktie vieglo aerojonu koncentrācijas un dažu meteoroloģisko faktoru mērījumi, kas veikti 2009. gada jūlijā – augustā. Analizējot iegūtos datus, izdarīti secinājumi, ka vispārējais gaisa jonizācijas līmenis pilsētā ir vidējs, atklāta vispārēja tendence negatīvo aerojonu koncentrācijai dienas laikā samazināties, bet pozitīvo aerojonu koncentrācijai pēcpusdienā pieaugt. Īsumā raksturots, kā pilsētas infrastruktūra ietekmē gaisa kvalitāti tajā, un sniegti priekšlikumi iespējamai pilsētas tālākai attīstībai. - PublicationLASER ABLATION OF PAINT COATINGS IN INDUSTRY(2021-06-17)
; ; ;Nikolay Angelov; ; A comparison is made between the laser and sandblasting methods for removing paint from industrial facilities. The advantages of laser ablation are discussed. The possibilities of laser paint removal systems - stationary and moving - are shown. The main factors influencing the laser ablation process and the indicators that determine the quality of the obtained surface are systematized. Researchers' publications on this technological process are analyzed. - PublicationLASER HARDENING USE FEATURES ON STEEL C45(2019-01-01)
; ;Teirumnieks, N.The paper investigates and describes laser hardening of steels, types of lasers, important parameters of laser hardening, as well as steels that are suitable for laser hardening process. The laser hardening process of steel C45 samples is described, the analysis of the results is described and the result is summarized. The results of the experiments show that laser hardening is capable of meeting the relevant requirements and quality parameters in steel C45 hardening. - PublicationLEGAL FRAMEWORK CONCERNING EMERGENCY REGIMES IN THE CONTEXT OF STATE BORDER SECURITY(2020-02-02)Arturs Gaveika
- PublicationNew device for air disinfection with a shielded UV radiation and ozone(2021)
; ;Mezule, L.; ;Pizica, V. ;Denisova, V. ;Skudra, A.; ; Juhna, T.Indoor air disinfection has become particularly relevant recently because of the Covid-19 pandemics. A shielded device for air and surface disinfection with UV radiation and ozone has been developed. It contains 28 low intensity (11 W) UV lamps (254 nm) in a specially designed three-dimensional grid to provide a large flow cross-sectional area and long path for the air particles to be irradiated. The device can be used in medical institutions, veterinary clinics, manufacturing plants, public premises, poultry, and livestock farms. It does not generate air-ions and ozone concentrations do not exceed the allowed 8-hour average values. The large number of UV lamps and powerful fans ensure air disinfection in large rooms in a relatively short time (400 m3 h -1 ). Simultaneously, the floor surface under the appliance is disinfected. Disinfection efficiency tests demonstrated 99.9999% reduction for Escherichia coli, Staphylococcus aureus and Pseudomonas phage Φ6 aerosols within a single transfer through the system (10 seconds of treatment). The housing of the device protects from direct UV radiation; therefore, people can be in the room during the operation of the device. - PublicationNO LATGALES LATVIEŠU KONGRESA LĪDZ LATVIJAS SUVERENITĀTEI(2017-07-22)Artūrs Gaveika1917. gada maijā Latgales latviešu kongresā pieņēma lēmumu: „Latgales, Vidzemes un Kurzemes latvieši ir viena tauta ar vienu valodu, un visiem ir jāapvienojas vienā valstī“ (Vītiņš, 1993), ko varētu uzskatīt par vienu no pirmajiem nozīmīgākajiem Latvijas suverenitātes paziņojumiem teritoriālā kontekstā. Tautu pašnoteikšanās tiesībās svarīgs ir teritoriālās jurisdikcijas princips, kuru tā laika perioda tiesību zinātnieks Verners Vītiņš raksturo tā: „Teritoriālās jurisdikcijas princips dod valstīm tiesības nepieļaut savā teritorijā tādus aktus, kas varētu radīt kaitējumu otrai valstij. Valsts vara ir nedalāma, t. i., visas valsts teritorijas robežās un daļās iedarbojas tikai viena augstākā valsts vara bez kādas citas valsts iejaukšanās“. 1919. gadā Latvija vēl netika atzīta „de jure“ Rietumu lielvalstu starpā, jo pat pēc Tautu Savienības izveidošanās tika cerēts, ka tiks atjaunota boļševistiskā Krievija un Latvija tiks inkorporēta Krievijā. Sākotnējo Latvijas valsts austrumu robežu noteica pēc Latvijas Brīvības cīņām (1918–1920), kad Padomju Krievijas karaspēku atspieda uz austrumiem Latvijai vēlamā attālumā. 1920. gada 30. janvārī Maskavā starp karojošām pusēm tika noslēgts pamiera līgums, kas noteica, ka abu valstu karaspēki ieņem līgumā noteiktās demarkācijas līnijas. Pēc šo līniju apraksta redzams, ka Latvija jau noteikusi aptuveno valsts austrumu robežu, kura galvenokārt iet pa lielākām un mazākām upēm, purviem, kā arī šķērso ezerus. Šķiet, ka Latvija, slēdzot šo pamiera līgumu, paredzēja, kādas grūtības tai sagādās sargāt austrumu robežu, un tādēļ noteica demarkācijas līniju pa dabas veidotiem šķēršļiem. Pirmā starptautiskā vienošanās par Latvijas robežu ar Padomju Krieviju bija 1920. gada 11. augusta miera līgums. Tāpēc tikai pēc Miera līguma noslēgšanas ar Krieviju zuda formālais šķērslis tam, lai Rietumu lielvalstis Tautu Savienībā atzītu Latviju „de jure“, kas arī notika 1921. gadā. Miera līguma ar Krieviju 2. pantā teikts: „Izejot no Krievijas Sociālistiskās Federatīvās Padomju Republiku pasludinātajām visu tautu tiesībām uz brīvu pašnoteikšanos, neizņemot pat pilnīgu atdalīšanos no valsts, kuras sastāvā tās ietilpst, un ievērojot Latvijas tautas noteikti izsacīto gribu uz patstāvīgu valsts dzīvi, Krievija bez ierunām atzīst Latvijas valsts neatkarību, patstāvību un suverenitāti un labprātīgi un uz mūžīgiem laikiem atsakās no visām suverēnajām tiesībām, kuras piederēja Krievijai attiecībā uz Latvijas tautu un zemi“. Šī līguma 3. pants noteica valsts robežu ar Krieviju, pēc kura Latvijā ietilpa arī Abrenes apgabals. Līgums faktiski bija kompromiss, kurš kopumā iezīmēja etnogrāfiskam principam atbilstošu robežu, izņemot nelielo Pitalovas iecirkni, kur latvieši jau sen bija mazākumā, bet uz kuru Latvija uzstāja ekonomisko (dzelzceļa mezgls) un, kā toreiz teica, stratēģisku (robežas iztaisnošana) motīvu dēļ.
- PublicationRESEARCH OF CARBON FIBER MATERIAL LASERCUT OPTIMIZATION(2019-01-01)
; ; ; Okunevs, A.The report considers the possibility of using laser technology for cutting products from carbon fiber. The study uses a fiber laser with a wavelength of 1080 ±10nm. The dependences of the width b of the cutting lines on power density q and processing speed v are considered. As a result of experimental studies, power density and speed parameters were optimized for high-quality cutting of the carbon fiber. - PublicationRESERCH OF LASER MARKING CHANEL GEOMETRICAL DIMENSIONS DEPENDENCE OF CHANGE OF LASER RADIATION PARAMETERS ON STAINLESS STEEL(2016-04-20)
;Dunkins, Vitālijs ;Komkovs, Jurijs ;Narica, Pavels ;Valiniks, Jānis; ; Publication describes results of the stainless steel laser marking, which shows relationship between geometry of the treated surface and parameters of the laser radiation, such as power, pulse frequency, and processing speed.