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- PublicationDAŽI DIELEKTRISKĀS CAURLAIDĪBAS PĒTĪJUMU ASPEKTI GUMIJAS MĀKSLĪGĀS NOVECOŠANAS PROCESOS(1999)Gumija ekspluatācijas laikā ir pakļauta ilgstošai dabiskai novecošanai, kuras rezultātā izmainās gumijas struktūra, pasliktinās elastīgās īpašības un mehāniskā izturība. Konstruktoram ir nepieciešams zināt, cik ilgi konkrētais gumijas izstrādājums dotajos apstākļos spēs kalpot. To var prognozēt uz paātrināto eksperimentu pamata. Šie eksperimenti ir saistīti ar gumijas mākslīgo novecošanu, kad pētāmajam paraugam papildus tiek pievadīta enerģija, iedarbojoties uz to ar temperatūras lauku, radiāciju, ķīmiski aktīvām vielām, vibrācijām vai kā citādi. Mākslīgajā novecošanā straujāk izmainās gumiju raksturojošie parametri un īsākā laikā sasniedz savas kritiskās vērtības, pie kurām gumijas izstrādājums vairs nav lietojams. Dotajā darbā kā viens no šādiem parametriem ir izvēlēta dielektriskā caurlaidība, mākslīgā novecošana tiek veikta paaugstinātā temperatūrā.
- PublicationGRUNTS STIPRINĀŠANA AR ELEKTROOSMOTISKĀS METODES PALĪDZĪBU(1999)
; Gunrads VaļģisDaudzos gadījumos nepietiekoši nostiprinātas grunts dēļ notiek nogruvumi, kuri izraisa ēku, būvju daļēju vai pilnīgu sagraušanu. Šī problēma pastāvēja jau ļoti sen, bet asāk tā sāka izpausties tieši mūsu gadsimtā, sakarā ar ļoti straujo industrializāciju, kurai vajag gan daudz būvmateriālu, tādējādi izveidojas karjeri, gan arī nostiprināt tās platības, uz kurām tiks veikta ēku celtniecība.Lai gan pastāv ļoti daudzas grunts nostiprināšanas metodes, savā darbā mēs apskatījām tikai vienu - grunts masīva nostiprināšanas metodi ar elektroosmozes palīdzību, kurai tika veikti arī praktiskie eksperimenti. Metode balstās uz elektriskās strāvas izmantošanu grunts stiprināšanai, tas ir, uz to, ka ūdens virzās no pozitīvā elektroda uz negatīvo elektrodu, papildus veicot ūdens atsūknēšanu no šī elektroda.Elektroosmoze - tā ir šķīduma kustība attiecībā pret cietu sienu, elektropotenciālu starpības ietekmē jeb šeit šķidrums pārvietojas cietā vidē. - PublicationZĪDAIŅU MIRSTĪBA KĀ VIDES KVALITĀTES INDIKATORS LATGALĒ(1999)Zīdaiņu mirstība atšķiras no kopējās iedzīvotāju mirstības problēmas ar savu īpašo sociālo, demogrāfisko un medicīnisko nozīmību. Tā ir viens no jūtīgākajiem jebkuras teritorijas vispārējā sociāli ekonomiskā, sanitārā un ekoloģiskā stāvokļa indikatoriem. Tādējādi zīdaiņu mirstību var uzskatīt par kompleksu vides kvalitātes indikatoru, ar vidi šajā gadījumā saprotot visu sociālo, ekonomisko un dabas faktoru un parādību kopumu, kas tiešā vai netiešā veidā ietekmē iedzīvotāju dzīves kvalitāti.
- PublicationSlēpto neironu loma tiešās izplatības tīklos(1999)Parādīta slēpto neironu loma tiešās izplatības mākslīgajos neironu tīklos. Slēpto neironu skaita izteiksme parasti tiek noteikta katrā atsevišķā gadījumā empīriski. Aprakstītas metodikas slēpto neironu skaita noteikšanai.
- PublicationEAST LATGALE SAA PROJECT(2001)
; Aigars MetlānsEast - Latgale Region including Rezekne city and district and Ludza City and disrtict. East - Latgale region occupies 5241 km2 (about 8% o f Latvia). There are 120273 inhabitants (4,9% o f Latvia's population). Registration of waste volume in region is formal, because waste going to dumpsites as a matter of fact is not controlled exept dumpsites used by largest towns. In East - Latgale region in year 2000 was 46 dumpsites and total waste volume 64700 m3. National Municipal Solid Waste Management Strategy foreseeing establish 10-12 new solid waste landfills in Latvia. The overall strategy in searching for a location of a new landfill includes three principal aspects: 1. The environmental impact o f a landfill has to be as low as possible. 2. The waste disposal interests should not conflict with other interests. 3. The selected site should be reasonable from economic viewpoint. Taking into consideration the above aspects, the division of the land in areas suitable and non-suitable for location of a new landfill was based on the following criteria: Geological structure and hydrogeological conditions; Distance to urban areas; Location o f particularly protected nature objects; Distance to surface water bodies. - PublicationAPPLICATION OF CLUSTERING METHOD IN THE RBF NEURAL NETWORKS(2001)This paper describes one of classification algorithms, cluster analysis, that plays a significant role in the implementation of learning algorithm as applied to RBF-type artificial mural networks. The mathematical description of the K-means clustering algorithm is given and its implementation is demonstrated by experiment.
- PublicationUsing grid-clustering methods in data classification(2002)
; A. BorisovThis paper examines grid-clustering method. Unlike the conventional methods, this method organizes the space surrounding the patterns. It uses a multidimensional grid data structure. The resulting block partitioning of the value space is clustered via a neighbor search. The mathematical description of the algorithms employed is given. Some case studies and ideas on how to use the algorithms are described.Scopus© Citations 25 - PublicationAnalyze of Leachate Composition in the Dumpsites of East-Latgale Region(2003)
; There are are 28 working or closed but not recultivated municipal solid waste dumpsites in East-Latgale now. A number of these dumpsites are situated near lakes, rivers, in old mineral quarries etc [3, 6]. All these dumpsites pollute groundwater, soil and present danger for human health. One of the dangerous factors is leachate which is generated in these dumpsites and which pollutes groundwate, soil and drinking water. The analysis of leachate sample chemical content in the biggest East-Latgale dumpsites “Ritini”, “Zvirgzdene”, “Zelceva” and “Mostovaja” has been done in 2002. The content of leachate depends on content of waste, dumpsite management etc. The most polluted leachate is in the biggest dumpsites of region – “Ritini” and “Zvirgzdene”. These are city dumpsites (Rezekne and Ludza). Significantly less polluted leachate is found in the dumpsites “Zelceva” and “Mostovaja”. This is valid for all analyzed parameters – COD, conductivity, Ntot., NH4 + and Cl. - PublicationEXTRACTING RULES FROM TRAINED RBF NEURAL NETWORKS(2005)This paper describes a method of rule extraction from trained artificial neural networks. The statement of the problem is given. The aim of rule extraction procedure and suitable neural networks for rule extraction are outlined. The RULEX rule extraction algorithm is discussed that is based on the radial basis function (RBF) neural network. The extracted rules can help discover and analyze the rule set hidden in data sets. The paper contains an implementation example, which is shown through standalone IRIS data set.
- PublicationGROUNDWATER, SURFACE WATER AND LEACHATE MONITORING IN HOUSEHOLD WASTE LANDFILL „GETLINI”(2005)
; - PublicationFINANCIAL FORECASTING USING NEURAL NETWORKS(2006)This paper presents an application of neural networks to financial time-series forecasting. No additional indicators, but only the information contained in the sales time series was used to model and forecast stock exchange index. The forecasting is carried out by two different neural network learning algorithms – error backpropagation and Kohonen self-organising maps. The results are presented and their comparative analysis is performed in this article.
- PublicationDATA PREPROCESSING METHODS FOR INTERVAL BASED NEURAL NETWORK PREDICTION(2007)The paper examines a task of forecasting stock prices of Riga Stock exchange by the use of interval value prediction approach, which is carried out by modified Kohonen neural network learning algorithm. The data preprocessing methods are analyzed and implemented here to solve stock prices prediction task. The proposed data preprocessing methods has been experimentally tested with two types of artificial neural networks.
- PublicationINVESTIGATIONS OF MUNICIPAL SOLID WASLE LANDFILLS LEACHALE TREATMENT(2007)
; - PublicationTRANSFORMATION OF URBAN LANDSCAPEIN LATGALE REGION ON CHANGE OF 20- 21 CENTURIES(2007)The paper deals with transformation of urban landscape in the 2 cities and 12 towns of Latgale region on change of 20-21 centuries, in the period from 1990 to 2007. Article provides information about factors and social economics processes that have influence on urban landscape structure and quality. The paper have a look at changes of land use structure, demographical processes, urban environmental quality, dynamics of urban transportation system and intensity of construction works in the cities and towns of Latgale region. The results establish disparities between scopes and directions of urban landscape transformation among different ranks of urban settlements.
- PublicationECOLOGICAL EXPEDITION AS EFFECTIVE FORM OF ENVIRONMENTAL RESEARCH AND ECOLOGICAL EDUCATION(2007)The paper deals with ecological expedition as effective form of environmental research and ecological education. Since 1997 Rēzekne Higher education institution organizes ecological expeditions for study programme “Environmental engineering” students in the Eastern Latvia region. Students realize integrated assessment of environmental quality with different methods. Article summarize experience of 10- years long period. Also show main goals and tasks of ecological expeditions, describe field research methods and cameral processing of data.
- PublicationConstruction Methods of the Decision Trees for Genetic Programming(2008)Mūsdienās ģenētiskās programmēšanas iespējas tiek plaši izmantotas daudzos optimizācijas un klasifikācijas uzdevumos. Lai ģenētiskās programmēšanas metodes varētu tikt veiksmīgi pielietotas, ir nepieciešams konstruēt attiecīgus lēmumu kokus. Lēmumu koki un likumi uz to pamata ir intelektuālās datu analīzes sastāvdaļa un veiksmīgi tiek pielietoti klasifikācijas problēmu risināšanā. Pastāv vesela virkne dažādu paņēmienu, kas dod iespēju konstruēt lēmumu kokus ģenētiskās programmēšanas iespēju izmantošanai. Literatūras analīze liecina, ka optimālākā metode lēmumu koku konstruēšanā sastāv no diviem etapiem. Sākotnēji tiek veidots lēmumu koks, izmantojot C4.5 algoritmu, kas turpmāk tiek izvērsts ar ģenētiskās programmēšanas operatoru palīdzību. Šajā gadījumā ģenētiskā programmēšana tiek lietota kā globāla meklēšanas stratēģija precīza lēmumu koka atrašanā. Rakstā analizētas mūsdienu pieejas lēmumu koku konstruēšanā un izskatītas ģenētiskās programmēšanas iespējas, kas tiks izmantotas turpmākajā pētnieciskajā darbībā.
- PublicationTHE SITUATION IN THE LATGALIAN COUNTRYSIDE AT THE BEGINNING OF THE AGRARIAN REFORM IN THE 1920s(2008)Malahovskis, VladislavsDuring the first independence of the Latvian Republic, the radical agrarian reform between 1920 and 1937 was the most important attempt to solve the agrarian problem. At the core of the reform was the nationalization of the estates, the buildings, the interior inventory and the cattle, and the distribution of the land which had become property of the National Land Fund (NLF) among landless peasants and small farmers. The objective of the paper is to identify the different factors that cumbered the beginning of the agrarian reform in Latgale and made it more complicated.
- PublicationA Meta-Model Based Approach to UML Modelling(2008)
; Scopus© Citations 5 - PublicationTHE ETHNOLINGUISTIC SITUATION IN INDRA MUNICIPALITY IN THE RURAL PART OF KRĀSLAVA REGION(2008)The research is based on the processed questionnaire data gathered during the ethnolinguistic expedition to Indra municipality in the rural part of the region of Kraslava in June, 2007 (120 respondents). The paper analyzes the answers of the respondents regarding the ethnic self-identification of the people, their knowledge of languages, the dominance of languages,, and their functions in the micro and macro environments of Indra municipality. The most important conclusions are: There is a noticeable difference between the official statistical data and the notions of ethnic belonging of the respondents: the official statistics state that the dominant ethnic group in Indra municipality are Belorussians; however, the major part of respondents consider themselves to be Russians. The Russian language dominates in verbal and written communication in both the micro and the macro environment. Many respondents admit that they speak „their own” language in the municipality - Russian with lexical, morphological and phonetical elements of Belorussian and Polish. The role of the Latgalian language in the rural municipality is not important; the respondents do not see any perspectives for its use in the future. The Latvian language as the official language is respected in the administration of the municipality; however, there is a wish to recognize both Latvian and Russian as official languages. The roles of the school (for the acquisition of the Latvian language) and of the Church (the language of praying is Polish, but masses are held in Russian and Latgalian) are important for the formation of the linguistic scenery of Indra municipality. In the polyethnic and multilingual environment of Indra municipality, there is a predominantly tolerant attitude towards different languages and ethnic groups.
- PublicationTHE NOTION OF HAPPINESS IN LATGALIAN FAIRY TALES(2008)Happiness as an ethical category and as one of the most universal dimensions of human world views has been recognized as one of the most important concepts in the specification of ethnic culture within the paradigm of humanitities. The objective of this paper is therefore to reveal the notion of happiness in Latgalian fairy tales. For this purpose, one hundred Latgalian fairy tales were selected in which the word ‘happiness’ was used in different forms and combinations. Taking into consideration the specifics of a folklore text, a linguoculturological approach was used to determine the notion of happiness in Latgalian folklore, and to observe the concept of happiness in folklore texts in the discourses of language and culture and of language and ethnic mentality (Маслова 2001: 28). This concept is interpreted in this paper as a body of collective knowledge, which expresses itself through language and which shows the specifics of an ethnic culture (Воркачев 2002: 22). Three components are distinguished in the structure of the concept – a notional, a figurative, and an axiological component. Of these, the notional component is considered to be the most important one by the majority of researchers (Карасик 1999: 39). It is disclosed in the semantics of the language of folklore when studying the lexemes that happiness is connected with, in the analysis of semantic and pragmatic aspects of the word ‘happiness’, regarding word combinations where happiness is described specifically along the most typical components, and from a contrastive view which allows to identify happiness in comparison to unhappiness. Contextual semantics of the notion of happiness reveals one of the most common theories of the notion of happiness – happiness as luck or as a coincidence of favorable circumstances. A lucky situation can in Latgalian fairy tales also be defined according to the importance of the task which has to be accomplished by a hero and when it is particularly difficult or even impossible to fulfil. In such cases, happiness is denoted with the use of adjectives and as an accomplishment, thereby changing the emphasis from chance to the lucky hero. In the end of the fairy tales, the adverb ‘laimeigi’ (‘happily’) or the adjective ‘laimeigs/-a’ (‘happy’) appears most often in combination with the word ‘dzeivuoja’ (‘lived’), thereby suggesting that there is a special awareness of the word combination „happy life” in Latgalian consciousness. Final formulas of fairy tales relating to the basic elements of happiness distinguish social well-being from the well-being of a family. In addition, fragments of other values contribute to elements of happiness in the final formulas, for example, life/health, harmony, and even loneliness. Under the influence of Christianity, wealth looses importance as a subject of happiness, and its place is taken by the combination of poverty and happiness. A perspective of action of the characters regarding happiness in fairy tales is also created by verbs, which allow to divide characters into three groups: those who look for happiness for themselves, those who give happiness to others, and those who try to deprive others of happiness. Traditionally, protagonists of fairy tales fall into the first group. Their actions are described by using the verbs ‘to look for’, ‘to get’, ‘to meet’, ‘to catch’, or ‘to inquire’, which all imply an active behaviour. In the second group there are so called magic helpers, whose actions are characterized by the verbs ‘to wish’, ‘to make’, ‘to give’, ‘to promise’, or ‘to enchant’. In the third group there are the antagonists of a hero who are best described with the word ‘to envy’. Verbs as a characterization of an attitude towards happiness attest an active position of the characters in the Latgalian fairy tales. Even when happiness is predetermined, the characters do not remain static but actively participate in securing happiness. According to the logic of mythological thinking, happiness is made understandable and organized in recognizable artistic images and positioned in the local environment in equivalence to humans. Two of the most popular artistic techniques of substantiating happiness are anthropomorphization and objectification, which evolve along demythologization. There are two ways of interpreting happiness as an anthropomorphic image. First, the characterization of happiness emphasizes elements symbolizing prosperity and wealth: happiness is dressed in gold and silver (12.A.735.), it appears as a corpulent woman (11.A.735.) or a beautiful girl whose wreath shines like the sun (7.), etc. The second technique is to describe the appearance of happiness in correspondence to the hero’s psychological notion of happiness – when a hero is unhappy, happiness is a black old maid (7.), pale or exhausted (15.A.735.567.). Typical of a hero’s attitude towards happiness are persistence and even superiority. Additional features in the anthropomorphic image of happiness are revealed in those fairy tales where happiness tries its strength against the personifications of other moral values, such as wisdom (8.A.736.). In the end of these fairy tales, wisdom has to admit that wisdom without happiness is not possible. Equally great significance of both moral values (also in reversed priority) is revealed in the paroemiac folk foundation: Laima bez gudreibas ir caurojs maiss. (LSD, 1940 2971) (Happiness without wisdom is like a sack full of holes). An objectification of happiness appears in fairy tales where the idea of happiness is immanently part of the idea of money as a source and a content of happiness. In these fairy tales money can appear to people in the form of a wolf, a bird, a midge, etc. Such an interpretation of happiness was probably determined by the human belief in happiness and the possibility of finding it. Happiness can appear in different unexpected ways, and humans shall only be prepared to recognize it and grasp it. The analyzed material of fairy tales shows how the Latgalians see, understand and evaluate happiness. To sum up the conclusions made in the paper, it shall be noted that happiness is one of the highest moral values of the Latgalians. It is interpreted as both luck and destiny. The Latgalians are active regarding happiness – they look for happiness and they find it. If necessary, they remind happiness of their existence and are not afraid of changing their lives. Regarding the content of values of happiness, the most important parts are well-being (different ways of wealth/prosperity) and family happiness (with a spouse or parents). However, under the influence of Christianity, fairy tales introduced also philosophical contemplation about the problem – whether happiness really is about wealth, whether a poor person can be happy, and whether happiness is possible in this world at all. Folklore does not give the one and only correct answer to what happiness is. Folklore shows where happiness could possibly be and how one can obtain it. Specific aspects of the interpretation of happiness in Latgalian folklore can also be found in other genres of folklore, for instance in folk songs and brahilogisms. It is very well possible that other ethnic groups emphasize different aspects in the interpretation of happiness which should be studied separately. However, as studies of the concept of happiness point out, due to the influence of globalization ethnic differences in the interpretation of happiness could be evened out (Veenhoven 1995: 5).