Papers by Justinas Rastenis
Remains of Gediminas Castle Hill (Vilnius, Lithuania): 3D Numerical Model Behaviour
Lecture notes in civil engineering, Oct 24, 2023
Identification of Gediminas Hill Possible Landslides Formations Zones
Rilem bookseries, Sep 1, 2023
Buildings
In this manuscript, we present the results of three-dimensional finite element analyses performed... more In this manuscript, we present the results of three-dimensional finite element analyses performed in the cloud of a large-scale model of the Gediminas Hill buildings and the construction remains of the Upper and Lower castles in Vilnius city. The greatest challenge associated with the simulated numerical model is the difficult geological layer surface inclinations and soil–structure interaction behavior prognosis, which require significant computational resources. The purpose of this research work is to present current and possible worst-case scenarios for Gediminas Hill, considering its buildings and construction remains, regarding the stability of its slopes through a safety analysis. The construction of a numerical three-dimensional model of Gediminas Hill allows for us to assess the soil–structure interaction behavior. The results of non-linear analysis on the created model are in agreement with the tendencies observed in direct geodetic measurements and the relevant landslide h...
Electronics, Mar 31, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Applied Sciences, 2020
The amount of fraud on the Internet is increasing along with the availability and the popularity ... more The amount of fraud on the Internet is increasing along with the availability and the popularity of the Internet around the world. One of the most common forms of Internet fraud is phishing. Phishing attacks seek to obtain a user’s personal or secret information. The variety of phishing attacks is very broad, and usage of novel, more sophisticated methods complicates its automated filtering. Therefore, it is important to form up-to-date and detailed phishing attack taxonomy, which could be used for both human education purposes as well as phishing attack discrete notation. In this paper, we propose an e-mail-based phishing attack taxonomy, which includes six phases of the attack. Each phase has at least one criterion for the attack categorization. Each category is described, and in some cases the categories have sub-classes to present the full variety of phishing attacks. The proposed taxonomy is compared to similar taxonomies. Our taxonomy outperforms other phishing attack taxonomi...
2019 Open Conference of Electrical, Electronic and Information Sciences (eStream), 2019
Wildfire is the dominant stand-renewing disturbance in the northwestern Canadian boreal forest. F... more Wildfire is the dominant stand-renewing disturbance in the northwestern Canadian boreal forest. Fires burn extensive areas in Canada, disturbing an average of 1.96 Mha yr −1 , primarily in the boreal zone. Fires generally occur every ~30-> 200 years in this region, due in part to a lack of fuel that allows young stands to resist reburning. Boreal understory plants and trees are adapted to stand-renewing wildfire through mechanisms such as serotiny, seed banking, and resprouting from roots and rhizomes of top-killed individuals. Such adaptations confer resilience to boreal forests, and post-fire vegetation communities generally resemble the pre-fire ones, following a stand self-replacement trajectory. Recently, the area burned, average fire size, and fire season length in northwestern Canada have increased. Severe fire weather has enabled reburning of young forests at very short intervals (sometimes ≤ 10 years between fires). Such changes in fire regime appear to be driven by anthropogenic climate change and increasingly severe fire weather. Furthermore, increasing moisture stress is implicated in simultaneous increases in fire activity, and worsening conditions for post-fire establishment of trees. Shifts in fire regime characteristics, such as burn severity and fire-free interval may lead to changes in vegetation composition following fire, thwarting stand self-replacement expectations. The 2014 and 2015 fire seasons in the Northwest Territories (NWT) and Northern Alberta (AB) were severe, with fires burning approximately 4 Mha, including instances of short-interval reburning. Inspired by these two fire years, in this dissertation I sought to understand the drivers of burn severity and the ecological outcomes of burn severity (biomass loss) and fire intervals, and how they interact with climate in this fire-adapted ecosystem. Specifically, my objectives iii were to: 1. characterize drivers and landscape patterns of burn severity, 2. describe the ecological outcomes of burn severity and fire history, and 3. examine the effects of post-fire moisture stress and fire regime on post-fire vegetation communities. These research objectives are contextualized in a methodological and ecological overview in Chapter 1. In Chapter 2 of this thesis I used remotely sensed multispectral imagery and field observations of burn severity to map landscape patterns of burn severity in six large wildfires. Fires were dominated by moderate-and high-severity patches. These patches were extensive, adjacent to similar patches, and had large core areas. Field measurements allowed me to demonstrate that burn severity was primarily a product of pre-fire vegetation structure (fuels) and hydrology (uplands and wetlands), providing a mechanism by which the severity of disturbance experienced is limited by the vegetation communities themselves. Similarly, field measurements of post-fire vegetation communities and shifts in tree species composition (Chapter 3) were largely explained by pre-fire forest structure, hydrology, and climate normals. The landscape of the NWT and AB was altered by the extensive area burned in 2014 and 2015, however, burn severity is highly variable. Post-fire ecological outcomes from these years are likely to be variable, as well. Although both site-and stand-level controls on burn severity and post-fire vegetation confer resilience, where fire activity and severity increase there is a possibility for forest change. I found evidence of post-fire shifts in tree species composition (Chapter 3). Black (Picea mariana) and white (P. glauca) spruce dominance declined in uplands following fire, whereas shifts in dominance of jack pine (Pinus banksiana) were variable, and trembling aspen (Populus tremuloides) dominance generally increased following fire. Where changes in tree species composition and density occurred, they were mediated by burn severity and fire frequency. iv Shortening of fire-free intervals due to drought is likely to accelerate climate-driven shifts from conifer-dominated boreal forests to open woodlands and grasslands. Paired sites that reburned at short fire-free intervals had significantly lower post-fire recruitment of trees than long-interval pair members, due to decreased establishment of conifers (Chapter 4). These differences were persistent and occurred in both uplands and wetlands. Increasing temperatures and aridity are likely to increase fire activity, and to reinforce the changes to forests caused by shifts in fire regimes. Post-fire moisture stress in both short-and long-interval sites interacted with burn severity, further reducing tree seedling density. This dissertation suggests that increasing wildfire activity and severity may alter the composition and structure of northwestern Canadian boreal forests, accelerating expected ecosystem changes as northern climates warm and dry. v Preface This thesis is the original work of Ellen Whitman. Ellen Whitman conducted the research for this dissertation as part of a collaboration between Natural Resources Canada and the government of the Northwest Territories department of Environment and Natural Resources, led by Marc-André Parisien at the Canadian Forest Service, Northern Forestry Centre. Ellen Whitman designed the field methods, and collected and processed all data. Those chapters (2 and 3) that are published works have been re-formatted for consistency, but the text has not been changed.
Electronics, 2021
Spamming and phishing are two types of emailing that are annoying and unwanted, differing by the ... more Spamming and phishing are two types of emailing that are annoying and unwanted, differing by the potential threat and impact to the user. Automated classification of these categories can increase the users’ awareness as well as to be used for incident investigation prioritization or automated fact gathering. However, currently there are no scientific papers focusing on email classification concerning these two categories of spam and phishing emails. Therefore this paper presents a solution, based on email message body text automated classification into spam and phishing emails. We apply the proposed solution for email classification, written in three languages: English, Russian, and Lithuanian. As most public email datasets almost exclusively collect English emails, we investigate the suitability of automated dataset translation to adapt it to email classification, written in other languages. Experiments on public dataset usage limitations for a specific organization are executed in...
Impact of Information Security Training on Recognition of Phishing Attacks: A Case Study of Vilnius Gediminas Technical University
Phishing attack is a type of social engineering attack and often used as the initial stage of a l... more Phishing attack is a type of social engineering attack and often used as the initial stage of a larger campaign. It is dangerous as users might inadvertently reveal to the attackers personal data or sensitive corporate information. Therefore, inability to recognize and properly react to phishing attacks must be treated as one of the main security risks in the enterprise. In this paper, we present a methodology for evaluating employees’ resistance to phishing attacks. We also analyze the changes to the situation after the employees participated in information security training. Experiments with employees of Vilnius Gediminas Technical University were carried out within a period of one year to gather information on how credulous they are to phishing attacks before and after security training. Results of the experiment reveal the benefit of security training, however there is still room for improvement and need to pay attention in the future.
Information Security Journal: A Global Perspective, 2018
Modern organizations strongly rely on various forms of data, ranging from communication technolog... more Modern organizations strongly rely on various forms of data, ranging from communication technologies to bookkeeping and manufacturing. It is a crucial asset of any enterprise, requiring special attention security-wise. One of the data security areas currently in focus is data leakage. It may occur due to malicious attacks, human error, unintentional data sharing, etc. Therefore it is important to predict all data leakage possibilities and prevent them. This paper proposes an Enterprise Management Structure (EMS) model for information flow data leakage probability estimation. The model evaluates the probability of data leakage according to possible human error and summarized security properties for data processing and transfer. Four different versions of small EMS are analyzed using the proposed model. The study concludes that its results meet expert evaluation tendencies and correlate with Bell-LaPadula confidentiality model.
Programinės įrangos integraciniai sprendimai
Disertacijoje nagrinėjama duomenų viliojimo elektroniniais laiškai problema ir galimi jos sprendi... more Disertacijoje nagrinėjama duomenų viliojimo elektroniniais laiškai problema ir galimi jos sprendimo būdai. Pagrindinis tyrimo objektas-duomenų viliojimo elektroniniais laiškais atakos. Šio tipo atakos priskiriamos socialinės inžinerijos atakoms ir yra vienas pagrindinių saugumui jautrių duomenų išgavimo būdų. Disertacijos tikslaspadidinti organizacijoms skirtų apsaugos priemonių kovoje su duomenų viliojimo elektroniniais laiškais gausą ir tikslingumą. Disertaciją sudaro įvadas, keturi skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai ir trys priedai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas ir uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pateikiamas autoriaus publikacijų ir pranešimų konferencijose disertacijos tematika sąrašas. Taip pat pateikta disertacijos struktūra. Pirmasis skyrius skirtas literatūros analizei. Čia pateikta nepageidaujamų elektroninių laiškų įvairovė, elektroniniais laiškais vykdomų atakų principai. Apžvelgiami galimi kovos būdai su elektroniniais laiškais vykdomomis atakomis. Skyriaus pabaigoje formuluojamos skyriaus išvados ir tikslinami disertacijos uždaviniai. Antrajame skyriuje gilinamasi į šiuo metu esamas duomenų viliojimo elektroniniais laiškais taksonomijas, jų vaizdavimo būdais. Nustačius esamų taksonomijų trūkumus, siūloma nauja duomenų viliojimo elektroniniais laiškais taksonomija. Pasiūlyta taksonomija lyginama su kitomis egzistuojančiomis taksonomijomis, vertinama, kaip taksonomijos naudojimas leidžia padidinti atakų aprašymo detalumą. Trečiame skyriuje gilinamasi į naudotojų pažeidžiamumą duomenų viliojimo atakoms ir saugos tema vykdomų mokymų efektyvumą naudotojų atsparumui didinti. Ketvirtame skyriuose pristatomi elektroninių laiškų, parašytų keliomis kalbomis, klasifikavimo modeliai. Šiame skyriuje pateikiamas teisėtų ir nepageidaujamų laiškų klasifikavimo modelis ir nepageidaujamų laiškų klasifikavimas į brukalo ir duomenų viliojimo laiškus. Disertacijos tema paskelbti 4 straipsniai: 2 straipsniai žurnaluose, įtrauktuose į Clarivate Analytics WoS duomenų bazę, abu turi citavimo rodiklį; 1 straipsnis publikuotas konferencijų straipsnių rinkinyje, referuotame Clarivate Analytics WoS duomenų bazėje; 1tarptautinių konferencijų straipsnių rinkinyje. Disertacijos tema skaityti 2 pranešimai Lietuvos ir tarptautinėse konferencijose.
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Papers by Justinas Rastenis