Latvian Grammar

“Latvian Grammar” was written to make information about the Latvian language and its grammatical system more easily available not only within Latvia, but also beyond its borders. A modern grammar of Latvian written in English is as important for native speakers of Latvian as for those who have learned Latvian as a second language and also is of great value for anyone interested in the culture and history of Latvia or the Latvian language itself. The need for a reference grammar of Latvian written in English is especially important right now due to the existence of a large Latvian diaspora community abroad, particularly in English-speaking countries where children and young people are educated in the language of their home countries rather than in Latvian. A Latvian grammar written in English will also be useful for those who are learning Latvian as a foreign language and wish to learn more about its grammatical system and unique features. Likewise, “Latvian grammar” will be a useful reference and source for examples for teachers of Latvian – both those who teach it to speakers as a school or university subject and those who teach it as a foreign language. There is also considerable demand among linguists abroad for a systematic and dependable description of Latvian written by native speakers of Latvian. Latvian is a rather unique combination of ancient as well as relatively new features, which are of interest to researchers abroad and are important for the typological, cognitive, pragmatic, functional, and contrastive analysis of language.University of Latvia State research program “Letonika – the history, languages, culture, values of Latvia

Subject case alternation in negated existential, locative, and possessive clauses in Latvian

[full article and abstract in English] The goal of this article is to analyse the alternation between the genitive and nominative cases in Latvian. As the alternation between genitive and nominative cases is possible in all clauses in which the verb būt ‘to be’ is used as an independent verb, this article examines existential, locative, and also possessive clauses, while also demonstrating that distinguishing these clause types is problematic for Latvian utilising the criteria given in the linguistic literature. Clauses containing the negative form of būt ‘to be’, i.e. nebūt, form the foundation of those selected for this study, as only in these sentences the genitive/nominative alternation can be seen for the subject in Latvian. There are only fragmentary descriptions of existential clauses as a unique semantic type, primarily in connection with the function of the verb būt ‘to be’ and the problems associated with distinguishing its independent and auxiliary meanings. Word order in existential, locative, and possessive clauses has, until now, been examined in connection with typical clause expanders – adverbial modifiers and the dative of possession as well as the information structure of the clause. At the same time, case choice for objects in negative existential clauses has traditionally been one of the most studied themes regarding language standardisation. In order to determine which factors affect the choice of either the genitive or nominative case, a corpus study was done analysing 979 examples: 882 with a genitive subject and 97 with a nominative subject. It was found that a connection exists between the definiteness of the subject, word order, and case choice; however, this manifests only as a tendency rather than as a strict rule.[straipsnis ir santrauka anglų kalba

Conception optimale de l'anode d'une cellule de production de fer par voie électrochimique

En raison de l’importance de la problématique du réchauffement climatique, il est vital de trouver des procédés de substitution aux procédés actuellement utilisés. La production de fer par la réduction des oxydes de fer par le charbon est un des procédés qui émet de grandes quantités de CO2 : ce constat a suscité la recherche d’autres types de procédés. Parmi les différentes voies possibles, c’est le procédé électrochimique de réduction du minerai de fer qui a été retenu [1]. Dans le procédé pilote en écoulement continu, l’anode est constituée de lames parallèles perpendiculaires au plan de la cathode. Il est connu que, dans les réacteurs électrochimiques, la présence de gaz augmente la chute ohmique [2]. L’objectif de ce travail est de proposer une conception optimisée de l’anode, permettant de réduire au mieux le temps de séjour de gaz afin de réduire la consommation énergétique. Dans ce but, nous avons étudié le désengagement des bulles d’oxygène dans une cellule de laboratoire. Une cellule fonctionnant en discontinu vis-à-vis de la solution a été conçue dans un premier temps dans le but d’évaluer le taux de vide et la vitesse ascensionnelle des bulles. Les bulles d’oxygènes atteignent leur vitesse terminale au bout de 20mm d’hauteur de l’anode. Aucune coalescence n’a été observée. Ceci est expliqué par les forces de répulsion dû à l’existence des charges négatives auteur de la bulle électrogénérée. Ces résultats expérimentaux ont montré que seule une portion de l’anode était effectivement efficace. Ces résultats ont ensuite été utilisés pour la réalisation d’une deuxième cellule à lames plus courtes fonctionnant en continu. Les mesures des champs de vitesse des bulles et du liquide sont effectuées pour différentes configurations et conditions opératoires, dans le but de choisir une géométrie permettant d’avoir les meilleures conditions de circulation de liquide et des bulles électrogénérées. 1. A. Allanore et al. Electrochim. Acta 55 (2010) 4007–4013. 2. L.J.J. Janssen and E. Barendrecht, Electrochim. Acta 28 (1983) 341–346. Cette étude a été financée par l’Agence Nationale de la Recherche dans le cadre du projet ASCoPE (Acier Sans CO2 Par Électrolyse) (ANR-EESI-2009-02

Sollicitations sismiques dues aux exploitations minières : amplification des ondes en surface (et vibrations des structures)

National audienceL'objectif de ce travail est d'analyser l'impact des secousses induites par les exploitations minières sur les structures situées en surface. Du fait des conditions géologiques locales, le mouvement créé par les secousses peut parfois être amplifié de façon importante en surface (effet de site). A partir d'une modélisation numérique du problème, l'amplification du mouvement est analysée pour différentes formes de remplissages sédimentaires et des contrastes de propriétés entre couches variables. Les valeurs de fréquences fondamentales (i.e amplification maximale) sont comparées à des résultats antérieurs

Developing a grid-connected DFIG strategy for the integration of wind power with harmonic current mitigation

The aim of this paper is to present a study of the efficiency of the electrical part of a wind generation system. Two back-to-back PWM voltage-fed inverters connected between the stator and the rotor are used to allow bidirectional power flow. The second inverter grid side, has a role of a power active filter, to eliminate the harmonic generated by the non linear load, in the same time gives an active and reactive power needed by the rotor of DFIG. The harmonics of switching frequency in the current stator, pose a major problem in the moment where commutations in the diode bridge, to solve this problem, we introduce a small-sized passive LC filter for the purpose of eliminating high-frequency shaft voltage and grid current from a DFIG driven by a voltage-source pulse width-modulation rotor inverter controlled with SVM. The control theory is discussed, and the controller implementation is described. Design criteria are also given. The results of simulation tests show excellent static and dynamic performances

An effective control of an isolated induction generator supplying DC load for wind power converting applications

The aim of this paper is to perform a simple and robust control method based on the well-known sliding control approach for a self-excited induction generator supplying an isolated DC load; this adopted technique does not require much computation and could be easily implemented in practice. In this context, the present work will begin with a mathematical development of this control technique and its application to the self-excited induction generator case. For this purpose, the machine provides the produced active power to the load through a static PWM converter equipped with a single capacitor on the DC side. In order to insure the output DC-bus voltage regulation with respect to the load-power demands and the rotor speed fluctuations, the required stator currents references are computed by considering the reactive power required for the machine core magnetization, the induced voltages through the stator windings and the active power set value obtained from the corresponding sliding mode DC-bus voltage controller. Regarding the nonlinearity of the DC-bus voltage mathematical model and the discontinuity characterizing the converter-machine behavior association, the sliding mode strategy will constitute a perfect tool to sizing the controller structure with high control performances. Results of simulation carried out to demonstrate the proposed control validity are presented.Целью данной статьи является разработка простого и надежного метода управления, основанного на хорошо известном подходе к управлению скольжением для асинхронного генератора с самовозбуждением, питающего изолированную нагрузку постоянного тока; данный принятый метод не требует больших объемов вычислений и может быть легко реализован на практике. В этом контексте данная работа начинается с развития математических основ этого метода управления и его применения в случае асинхронного генератора с самовозбуждением. Для этого машина подает произведенную активную мощность в нагрузку через статический ШИМ-преобразователь, оснащенный единственным конденсатором на стороне постоянного тока. Чтобы обеспечить регулирование выходного напряжения шины постоянного тока с учетом требований к нагрузке и колебаниям скорости вращения ротора, требуемые токи статора рассчитываются с учетом реактивной мощности, необходимой для намагничивания сердечника машины, наведенных напряжений в обмотках статора и заданного значения активной мощности, полученного из соответствующего контроллера напряжения шины постоянного тока в режиме скольжения. Что касается нелинейности математической модели напряжения шины постоянного тока и неоднородности, характеризующей поведение системы «преобразователь-машина», стратегия скользящего режима будет представлять собой идеальный инструмент для определения размеров конструкции контроллера с высокими характеристиками управления. Для демонстрации обоснованности предлагаемого метода контроля, приведены результаты выполненного моделирования

Application of Alkali-Activated Palm Oil Fuel Ash Reinforced with Glass Fibers in Soil Stabilization

The feasibility of using palm oil fuel ash (POFA) as a precursor for alkali activation reactions, in combination with glass fibers as a discrete reinforcement, has been investigated. The experimental work was focused on the shear strength (using unconfined compression tests) and the tensile strength (using indirect tensile tests and flexural tests). According to the results, it was found that the peak stress increased and the post-peak behavior was modified from a brittle to a more ductile response depending on the amount of fiber reinforcement in the alkali-activated mixtures. An analysis of the microstructures revealed that the most significant factor contributing to the enhanced behavior of the reinforced mixtures was the interaction between the geo-polymeric matrix and the fiber surface. The present work brings new insights to the soil stabilization industry by providing an effective method for enhancing the properties of soil treated by the alkali activation of POFA (a low-value agro-waste by-product) through the inclusion of glass fibers. This brings advantages over the traditional calcium-based binders (i.e., lime and cement) as their production involves the emission of carbon dioxide, one of the factors significantly contributing to global warming

The reflections of urbanization on the cultural identity of Algerian youth a field study on a sample of the youth of Laghouat

تهدف الدراسة إلى تسليط الضوء على البيئة الحضرية بمدينة الأغواط، ومعرفة تأثير التحضر الحاصل بالمدينة على فئة الشباب من ناحية الهوية الثقافية، وكذلك معرفة العادات والقيم التي يكتسبها الشباب من الوسط الحضري بمدينة الأغواط، ومدى التفاعلات الاجتماعية التي تكسب هوية ثقافية معينة،ومن جهة أخرى معرفة تأثير التحضر على الانتماء القبلي لدى الشباب، وقد تم الاعتماد على المنهج الوصفي، حيث تم تصميم استبيان وُزع الكترونيا على عينة قصدية من الشباب بمدينة الأغواط.  وقد كشفت نتائج الدراسة أن هناك علاقة بين جنس المبحوثين وإتباع الموضة في اللباس حيث أن معظم الشباب من أفراد العينة يواكبون التطور الحاصل نتيجة للتحضر بنسبة 54.54% ، فقد غير طريقة لباسه التقليدي بما يناسب الموضة الجديدة بغض النظر عن هويته الثقافية السائدة، كما أشارت النتائج أن التحضر أثر على الانتماء القبلي نسبيا داخل المدينة مقارنة بالانتماء القبلي داخل القرى أو البادية حيث أكد المبحوثين بنسبة%  55 أن المدينة تساعد نسبيا فقط على الانتماء القبلي، في حين توجد علاقة بين المستوى التعليمي للمبحوثين  ومن يختارون لمشاركة مشاريعهم بنسبة قدرت بـ  54.54% .The study aims to shed light on the urban environment in the city of Laghouat, and to know the impact of urbanization in the city on the youth category in terms of cultural identity, as well as the recognition of the customs and principles ​​that young people acquire from the urban center in Laghouat, and the extent of social interactions that earn a certain cultural identity, and on the other hand knowledge The upshot of urbanization on the tribal affiliation of young people. The descriptive approach was relied on, where a questionnaire was designed and distributed automatically to an intentional sample of young people in Laghouat. The results of the study exposed that there is a relationship between the gender of the respondents and following the fashion in dress, as most of the young people in the sample keep pace with the development that is taking place as a result of urbanization by 54.54%. Urbanization affected the tribal affiliation relatively within the city compared to the tribal affiliation within the villages or the Badia, where 55% of the respondents confirmed that the city only helps relatively to tribal affiliation, while there is a relationship between the educational level of the respondents and those who choose to participate in their projects, at a rate estimated at 54.54%

Subject case alternation in Latvian and Estonian existential clauses

In Latvian and Estonian existential clauses, the subject’s case form alternates between nominative vs. genitive (in Latvian) and nominative vs. partitive (in Estonian). This article is a study of the case-alternation systems of existential clauses and related clause types, locative and possessive clauses in these languages. It includes a corpusbased analysis of Latvian existential clauses that is being compared with Estonian corpus-based findings on similar clause types in Estonian. *** "Subjekti käändevaheldus läti ja eesti keele eksistentsiaallausetes" Nii eesti kui ka läti keeles esineb subjekti käändevaheldust. Läti keeles saab subjekt olla lisaks nominatiivile ka genitiivis, eesti keeles lisaks nominatiivile ka partitiivis. Artiklis võrreldakse subjekti käändevaheldust mõlema keele kirjaliku variandi eksistentsiaallauses, lisaks vaadeldakse ka eksistentsiaallausega seostuvaid lausetüüpe: lokatiiv- ja possessiivlauset. Läti keele subjekti käändevaheldus leiab aset eitavates lausetes verbiga nebut ‘mitte olema’, mida nimetame tinglikult eksistentsiaal-, possessiiv- ja lokatiivlauseteks. Kõigis lausetüüpides domineerib genitiivsubjekt mõjukalt nominatiivsubjekti üle. Eesti keele subjektikäände varieerumine ilmneb kõige produktiivsemalt eksistentsiaal- ja possessiivlausetes, seejuures on olulisemateks käändevaliku mõjuriteks lause polaarsus ja subjekti referendi kvantitatiivne määratletus. Esitame tänapäeva läti keele korpusematerjalil põhinevaid uuringutulemusi ning kõrvutame neid seniste uuringutega läti ja eesti keele kohta. Erinevalt varasematest seisukohtadest ilmneb, et lausetüübil peaaegu puudub mõju läti keele subjektikäändele. Uurime seetõttu peamisi subjekti käänet mõjutavate muutujate klastreid, keskendudes nende erinevatele realiseerumisvõimalustele. Peamised muutujad on subjekti referendi definiitsus, subjekti sõnaliik, subjektifraasi raskus ning subjekti paiknemine predikaadi ja määruse suhtes. Andmetest ei ilmne tugevaid reegleid, vaid ainult eelistuste tendentsid. Kõigis vaadeldavates lausestruktuuritüüpides on sagedasem genitiivsubjekt, kuid ülekaalukuse määr varieerub. Korpusematerjali suurim rühm subjekte on verbijärgsed indefiniitsed genitiivsubjektid. Nominatiivi kasutus on kõige sagedasem verbijärgsete definiitsete subjektide puhul, ületades kahekordselt nominatiivsubjektide osakaalu kogu uuritud korpusematerjalis. Teatud puhkudel on ka lausetüüp subjektikäände osaliseks mõjutajaks. Näiteks on eitavas lokatiivlauses, mille sõnajärg meenutab jaatavat lokatiivlauset, definiitne subjekt just nominatiivis. Artikkel esitab läti keele uuringutulemuste kõrvale tänapäeva eesti keele korpusematerjalil põhinevaid kvalitatiivseid ja arvulisi andmeid eesti keele võrreldavate subjektikäände tegurite ja tingimuste kohta