Vilnius University Press Scholarly Journals
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Comparative approaches to solving the (2 + 1)-dimensional generalized coupled nonlinear Schrödinger equations with four-wave mixing
No full textThis paper extensively studies the propagation of optical solitons within the framework of (2 + 1)-dimensional generalized coupled nonlinear Schrödinger equations. The investigation employs three worldly integration techniques: the enhanced direct algebraic method, the enhanced Kudryashov method, and the new projective Riccati equation method. Through the application of these methods, a broad spectrum of soliton solutions has been uncovered, including bright, dark, singular, and straddled solitons. Additionally, this study reveals solutions characterized by Jacobi andWeierstrass elliptic functions, enriching the understanding of the dynamics underpinning optical solitons in complex systems. The diversity of the soliton solutions obtained demonstrates the versatility and efficacy of the employed integration techniques and contributes significantly to the theoretical and practical knowledge of nonlinear optical systems
Fixed point results for single and multivalued three-points contractions
No full textIn this paper, we are concerned with the study of the existence of fixed points for single and multivalued three-points contractions. Namely, we first introduce a new class of singlevalued mappings defined on a metric space equipped with three metrics. A fixed point theorem is established for such mappings. The obtained result recovers that established recently by the second author [E. Petrov, Fixed point theorem for mappings contracting perimeters of triangles, J. Fixed Point Theory Appl., 25(3):74, 2023] for the class of single-valued mappings contracting perimeters of triangles. We next extend our study by introducing the class of multivalued three points contractions. A fixed point theorem, which is a multivalued version of that obtained in the above reference, is established. Some examples showing the validity of our obtained results are provided
On a novel type of generalized simulation functions with fixed point results for wide Ws-contractions
No full textOne of the most significant hypotheses in fixed point theory is the nonexpansivity condition of contractive mappings. This property is crucial as operators that do not satisfy this criterion may lack fixed points. In this paper, we propose a novel condition that, within the appropriate framework, can obviate the necessity of imposing the nonexpansivity requirement in the initial hypotheses. By employing this new condition, we illustrate how innovative results can be derived in this area. Finally, we examine the existence and uniqueness of a solution for an elastic beam equation with nonlinear boundary conditions grounded in the introduced fixed point results
Control of the servo motor using feedback linearization and artificial gorilla troops optimizer
No full textThis paper establishes a nonlinear optimization strategy for position control of a direct current motor. When experimental evidence showed that the linear model does not sufficiently represent the system, the model is modified from linear to nonlinear, using friction-induced nonlinearity. In the course of the research, an analysis of the nonlinear feedback linearizing controller and the up to date gorilla troops optimization algorithm are carried out. The proposed algorithm is juxtapose with four others metaheuristic optimizations. Furthermore, performances with and without different types of disturbances are compared for individual desired output signals. The experimental results corroborate the nonlinear control’s robustness
Exploring the Religious Identity of Dalits through the Lens of Religious Conversion
No full textThe paper examines the role of religion among Dalits in India, especially focusing on Dalit religious conversion from Hinduism to Buddhism. It is based on a case study of Dalit conversion in Shabbirpur village in the Northern Indian state of Uttar Pradesh. In line with the existing research on Dalit conversions, this paper shows that Dalit conversion in Shabbirpur serves not merely as a religious but also as a political and social strategy of Dalits through which they try to negotiate their caste identity. For Dalits, conversion means a resistance to caste oppression as well as assertion of divergent religious identity from the majoritarian Hindu identity. While exploring the Dalit religious identity following their conversion in Shabbirpur, the paper challenges the prevailing notion that religious conversion simply denotes a transfer of religious affiliation. Instead, it elucidates that Dalit religious conversion is a social process wherein Dalits’ transition from one religion to another devoid of a fundamental spiritual transformation. Through this case study, I argue that there exists a continuation of the past and present spiritual affiliation which involves hybridization of religious practice, fusing worship of Ravidas with a new Buddhist identity. Interestingly, this syncretization is not unintentional. It is a conscious attempt to keep both pre-and post-converted religious traits as part of their re-invented socio-religious identity
Rethinking a Better Life – (Im)mobility Experiences of Vilnius Roma Families
No full textMost of the Vilnius Roma families are actively engaged in transnational family networks shaping their everyday life, their social imaginations and life trajectories. When discussing the migratory experiences and the meaning of a better life, there is a constant comparison between ‘here’ and ‘there’, or between lives in Lithuania and abroad. ‘Here’ is a place where Roma are always spotted and stigmatised, while ‘there’ assures invisibility and, hence, more opportunities. The circulating ideals about the ‘abroad’ can be read as a disappointment with a life ‘here’ – what is idealised, fantasised and seen as a goal ‘out there’, it is what people would wish to have in Lithuania. This comparison and lived experiences are becoming a collective community knowledge that is shared among all generations – one does not have to really experience life abroad to know that there is a place where everyone “can feel a human being.” But can the imagined paradise be also criticised and questioned? Can a better life be related only to some geographical space and socio-economic experiences? This chapter is based on a long-term ethnographic fieldwork among Vilnius Roma families
Sekėjų požiūris į socialinių medijų nuomonės formuotojo savęs atskleidimo reklamoje poveikį nuomonės formuotojui sekti ir sekėjų sprendimui pirkti reklamuojamus prekių ženklus
No full textInfluencers are intermediaries between the consumer and the brand who can influence the consumer’s purchasing decisions. Research suggests that influencers’ self-disclosure can have an impact. In the absence of a deeper insight into consumers’ attitudes towards the impact of this information on their purchase decision, the present study aims to identify the attitudes of the followers of influencer X in the study towards the impact of X’s different self-disclosures on X’s following, and on the decision to buy the brands X promotes. Interview participants revealed that self-disclosure information from all personality backgrounds is important for their X-following. The overlap between the self-disclosure information in the advertisement and in the profile is important for the participants. The importance of peripheral and intermediate personality layer information was related to trust in X. X’s attractiveness. They felt that X’s self-disclosure did not ensure X’s expertise. The positive effect of X’s self-disclosure in advertising on the purchase decision of the participants in the study was, in their view, related to the reproduction of peripheral personality information; the effect of intermediate personality information on the purchase decision was recognized in the interaction with X’s other profile information. It was found that if the participants in the study have a skeptical attitude towards influencer advertising, self-disclosure in advertising does not influence their purchase decision.Socialinių medijų nuomonės formuotojai yra tarpininkai tarp vartotojo ir prekių ženklo, galintys daryti poveikį vartotojų sprendimui pirkti. Moksliniuose tyrimuose teigiama, kad tam poveikį gali turėti nuomonės formuotojų savęs atskleidimas. Trūkstant gilesnio žvilgsnio į vartotojų požiūrį dėl šios informacijos poveikio jų sprendimui pirkti, pristatomame tyrime užsibrėžiama nustatyti tyrime dalyvaujančių X sekėjų požiūrį į socialinių medijų nuomonės formuotojo X savęs atskleidimo skirtingos informacijos poveikį šiam nuomonės formuotojui sekti ir sprendimui pirkti jo reklamuojamus prekių ženklus. Interviu su tyrimo dalyviais atskleidė, kad socialinių medijų nuomonės formuotojui X sekti aktuali visų šios asmenybės sluoksnių savęs atskleidimo informacija. Tyrimo dalyviams svarbi savęs atskleidimo informacijos reklamoje ir profilyje sutaptis. Periferinės ir tarpinės asmenybės sluoksnių informacijos svarbą respondentai sieja su pasitikėjimu X, patrauklumu. Tyrime dalyvavusiųjų manymu, X savęs atskleidimas neužtikrina jo ekspertiškumo. Teigiamas X savęs atskleidimo reklamoje poveikis tyrimo dalyvių sprendimui pirkti sietinas su periferinės asmenybės informacijos atkleidimu, o tarpinės asmenybės informacijos poveikis sprendimui pirkti pripažįstamas šiai informacijai sąveikaujant su kita X profilio informacija. Jei tyrimo dalyvių požiūris į socialinių medijų nuomonės formuotojų reklamą skeptiškas, savęs atskleidimas reklamoje nedaro poveikio respondentų sprendimui pirkti
Revoliucinė dora: Maximilieno Robespierre’o išpažinta (anti)religija Prancūzijos revoliucijos metu
No full textThe aim of this paper is to gain insight into Maximilien Robespierre’s (1758–1794) religious consciousness. He, like his fellow and enemy revolutionaries, lived in a world where it was more understandable to be religious than to not to be. With the outbreak of the French Revolution, it can be seen that Robespierre used religious or religiously subtextual signs in his rhetoric. While scholars have noted that Robespierre established the Cult of Supreme Being, it is evident that his faith was prominently more multifaceted and nuanced. An analysis of his rhetoric reveals the presence of an authentic personal faith, which he leveraged to combat his political enemies, justify revolutionary violence, and advance the goals of the French Revolution.Pagrindinis šio teksto rūpestis – bandyti suprasti Maximilieno Robespierre’o (1758–1794) religinę sąmonę Prancūzijos revoliucijos metu. Jis, kaip ir jo bendražygiai bei priešai revoliucionieriai, gyveno pasaulyje, kuriame buvo suprantamiau būti religingam nei nebūti. Robespierre’o retorikoje nuo Prancūzijos revoliucijos pradžios galima aptikti religinius simbolius ar religines potekstes atspindinčių motyvų. Nors dauguma tyrėjų pažymi, kad Robespierre’as įsteigia Aukščiausiosios Būtybės tikėjimą, atliekant tyrimą tampa akivaizdu, kad Robespierre’o tikėjimas buvo daug įvairiapusiškesnis ir niuansuotesnis. Išanalizavus jo retoriką, galima identifikuoti autentišką asmens tikėjimą, kuriuo jis naudojosi kovodamas su politiniais priešais, legitimizuojant revoliucinį smurtą ir nurodant Prancūzijos revoliucijos tikslą
Vietinių turistų skaičiaus Lietuvos apgyvendinimo įstaigose prognozavimas naudojant „Google Trends“ duomenis
No full textŠiame darbe į laiko eilučių prognozavimo modelius – sezoninį ARIMA modelį su egzogeniniais kintamaisiais (SARIMAX) ir atraminių vektorių regresiją (AVR) – įtraukiami internetinės paieškos sistemos „Google“ duomenys, siekiant pagerinti modelių tikslumą vietinių turistų skaičiaus Lietuvos apgyvendinimo įstaigose prognozavimui. Nustatyta, jog modeliai, sudaryti naudojant „Google Trends“ duomenis, pasižymi mažesnėmis paklaidomis.Šiame darbe į laiko eilučių prognozavimo modelius – sezoninį ARIMA modelį su egzogeniniais kintamaisiais (SARIMAX) ir atraminių vektorių regresiją (AVR) – įtraukiami internetinės paieškos sistemos „Google“ duomenys, siekiant pagerinti modelių tikslumą vietinių turistų skaičiaus Lietuvos apgyvendinimo įstaigose prognozavimui. Nustatyta, jog modeliai, sudaryti naudojant „Google Trends“ duomenis, pasižymi mažesnėmis paklaidomis
Decoding An Automobile’s Technical Specification From Its Identification Number
No full textWe propose a method for decoding technical vehicle‘s parameters (make, model name, body type etc.) from its identification number. Classification is done for the entire specification at once, thus utilising the underlying dependencies between labels. To achieve the goal, several models were used – nearest neighbours, decision tree, extra trees and random forest classifiers