43 research outputs found
Cybersecurity in Critical Infrastructure Systems: Emulated Protection Relay
Cyber-attacks on Critical Systems Infrastructure have been steadily increasing across the world as the capabilities of and reliance on technology have grown throughout the 21st century, and despite the influx of new cybersecurity practices and technologies, the industry faces challenges in its cooperation between the government that regulates law practices and the private sector that owns and operates critical infrastructure and security, which has directly led to an absence of eas- ily accessible information and learning resources on cybersecurity for use in public environments and educational settings. This honors research thesis addresses these challenges by submitting the development of an openly available learning resource for use as an introduction to standard cybersecurity processes and vulnerabilities. The primary objective of the development system is a portable, entirely virtual simulated microgrid for research, study, and outreach, which can be hosted in a fully cloud-based environment and accessible anywhere. This simulated microgrid is realized through the Typhoon HIL Control Center software, interfacing with physical Typhoon HIL hardware and a Raspberry Pi microcontroller running OpenPLC protection relay software and hosting a Modbus TCP server. Data simulation is securely transmitted to another virtual machine housing the Ignition Automation client software through a Modbus TCP connection, showcasing a user-end Supervisory Control and Data Acquisition (SCADA) system. This research project uti- lizes a realistic cyber-attack with and without the implemented preventive measures to demonstrate the instrumental role of proper cybersecurity protections for safely maintaining vital infrastructure frameworks
Expansion of water chestnut in a small dam reservoir: from pioneering colony to dense floating mat
Background and Purpose: This manuscript reports on the rapid spread of water chestnut in a shallow dam reservoir. The water chestnut is a critically endangered plant in Poland. Materials and Methods: From 2008 to 2016 during the vegetation season we investigated the distribution of water chestnut in the Rzeszów dam reservoir.Results: The colony has grown from sparse individual plants which probably appeared around 2005, to a dense floating mat of plants with the total area of over 14 ha today. Recently water chestnut has also appeared in all shallow parts of the reservoir with weak water flow. Conclusions: Taking into consideration the dynamic expansion of the water chestnut, it can be assumed that in the near future this species may control many parts of the Rzeszów reservoir, while in others it can be displaced by reeds. It is highly probable then that the total area of water chestnut patches will decrease, rather than increase.</p
Biomechanical responses to changes in friction on a clay court surface
Objectives: To examine the influence of clay court frictional properties on tennis players’ biomechanical response.
Design: Repeated measures
Methods: Lower limb kinematic and force data were collected on sixteen university tennis players during 10 x 180° turns (running approach speed 3.9 ± 0.20 m.s-1) on a synthetic clay surface of varying friction levels. To adjust friction levels the volume of sand infill above the force plate was altered (kg per m2 surface area; 12, 16 and 20 kg.m-2). Repeated measures ANOVA and Bonferroni’s corrected alpha post-hoc analyses were conducted to identify significant differences in lower limb biomechanics between friction levels.
Results: Greater sliding distances (ŋp2= 0.355, p = 0.008) were observed for the lowest friction condition (20 kg.m-2) compared to the 12 and 16 kg.m-2 conditions. No differences in ankle joint kinematics and knee flexion angles were observed. Later peak knee flexion occurred on the 20 kg.m-2 condition compared to the 12 kg.m-2 (ŋp2 = 0.270, p = 0.023). Lower vertical (ŋp2 = 0.345, p = 0.027) and shear (ŋp2 = 0.396, p = 0.016) loading rates occurred for the 20 kg.m2 condition compared to the 16 kg.m2.
Conclusions: Lower loading rates and greater sliding distances when clay surface friction was reduced suggests load was more evenly distributed over time reducing players’ injury risks. The greater sliding distances reported were accompanied with later occurrence of peak knee flexion, suggesting longer time spent braking and a greater requirement for muscular control increasing the likelihood of fatigue
Reakcje bezkręgowców bentosowych na akumulację drobnoziarnistego osadu w potoku górskim
Gospodarka leśna często wiąże się z niszczeniem pokrywy glebowej, a drogi leśne ułatwiają dopływ wyerodowanej gleby do potoków i ich zamulanie. Celem pracy była ocena stanu ekologicznego potoku narażonego na zamulanie na podstawie składu zespołu bezkręgowców bentosowych. Badaniami objęto potok Tym (Pogórze Przemyskie), mający charakter cieku górskiego, z dość dużym spadkiem koryta i kamienisto-żwirowym dnem. Zmiany w korycie potoku związane były z wynikającą z prac leśnych akumulacją drobnoziarnistego osadu na dnie. Wyznaczono 4 stanowiska badawcze: dwa w strefie akumulacji osadów i dwa na odcinkach niezamulonych. Oceniano parametry morfologiczne koryta, fizyko-chemiczne wody oraz pobierano próby makrozoobentosu. Dopływ drobnoziarnistego osadu, który pokrywał dno potoku, skutkował wyraźnym zaburzeniem składu fauny bezkręgowej. Pogorszyły się warunki siedliskowe dla bezkręgowców związanych z podłożem kamienistym i szybko płynącą wodą, tj. dla widelnic, jętek i chruścików. Natomiast na dnie pokrytym osadem mineralnym licznie były larwy Chironomidae i skąposzczety
The effects of brown trout on salamander larvae habitat selection: a predator-avoidance strategy
Predatory fish can have a major impact on aquatic amphibian assemblages. Knowledge on the influence of habitat heterogeneity on predator-prey dynamics is extensive, but not much is published on how the habitat structure influences the co-occurrence of brown trout (Salmo trutta m. fario L., 1758) and fire salamander (Salamandra salamandra (L., 1758)). I examined the microhabitat distribution of salamander larvae in relation to the presence of brown trout and stream morphology, hypothesizing that larval salamanders will increase their habitat use in the presence of trout to avoid predation. Fish and salamanders were sampled with a electroshocker, in 62 instream habitat patches. In the stream zone populated by brown trout, larval salamanders avoided high quality habitats such as pools, whereas they strongly preferred them in the fishless zone (in pools their densities were ~10 times lower than in riffles). Brown trout mainly occupied deeper pools. The co-occurrence of fire salamander larvae with trout suggests the presence of an effective predator-avoidance strategy. The predator-avoidance response and habitat use pattern decreased interspecific overlap, leading to the use of different instream spaces. Heterogeneous habitats enable habitat partitioning between salamander larvae and brown trout, which means that the natural characteristics of streams promote coexistence between fish and amphibians.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
The relationship between video games and literature in modern visual culture
Praca skupia się na zależnościach między grami wideo a literaturą. Przedstawiono możliwe źródła rozwijającej się współcześnie kultury wizualnej. Omówiono rolę gier wideo w obecnych czasach. Skupiono się na zjawiskach łączących gry z literaturą, takie jak literatura grywalna czy zjawisko novelization, a także opisane zostały modele narracyjne wykorzystywane w grach wideo.The main concern of this thesis is the relationship between video games and literature. The sources of developing modern visual culture have been described as well as the role of video games nowadays. Phenomena of video games being connected to literature such as playable poetry or novelization have beed discussed. Narrative models that are used in video games have been enumerated
Correspondence between Krystyna Skwarko and Krystyna and Czeslaw Bednarczyk
Praca zawiera korespondencję prowadzoną w latach 1971–1982 przez Krystynę Skwarko, przebywającą na emigracji w Nowej Zelandii nauczycielkę i pisarkę, oraz Krystynę i Czesława Bednarczyków, właścicieli emigracyjnego wydawnictwa Oficyna Poetów i Malarzy. Korespondencja opatrzona jest wstępem omawiającym najważniejsze zagadnienia, takie jak życiorys i twórczość Skwarko czy działalność Bednarczyków, a także notą edytorską i przypisami.This thesis contains correspondence from 1971–1982 between Krystyna Skwarko, emigrant teacher and writer residing in New Zealand after World War II, and Krystyna and Czeslaw Bednarczyk, owners of emigrant publishing house Poets’ and Painters’ Press. The correspondence is provided with an introduction describing the most important issues, such as Skwarko’s biography and work and Bednarczyks’ activity, and also with an editorial note and footnotes
Beaver impact on stream fish life histories : the role of landscape and local attributes
The Eurasian beaver (Castor fiber) has been reintroduced into the Carpathian Mountains and has once again become an important factor for modifying streams. Forty-three sampling sites were compared with 10 reference sites in streams not settled by beavers. Models related to the impacts of beavers on various fish life history stages and a model presenting attributes influencing the ichthyofauna structure in streams with and without beavers were generated. Significant differences in the fish species composition were found between beaver ponds versus the running sections of streams. The changes associated with pond aging caused decrease of Siberian bullhead (Cottus poecilopus) density. For brown trout (Salmo trutta), beaver ponds were the only location where large individuals were found, while the upstream parts of the beaver complexes provided spawning habitat and an area for fry growth. Common minnow (Phoxinus phoxinus) and stone loach (Barbatula barbatula) had higher density in ponds than in streams. The decisive factors for the ichthyofauna in the mountain streams settled by beavers were local attributes related to beaver activity. Our results illustrate interactions among beaver, landscape context, and fish life history in influencing the response of the stream fish assemblages to beaver recolonization. It also helps answer the question of how Eurasian beaver influence stream fish assemblages, at a much larger scale than previous studies. </jats:p