This thesis describes two proposed schemes that could be used to secure mobile messaging (SMS/MMS) as well as one scheme that could be used to secure mobile content. The security services we considered in securing the mobile messages are confidentiality, authentication, non-repudiation and integrity. We used Identity Based Cryptography in order to secure the mobile messaging and Blowfish algorithm to secure the mobile content. Due to some of the disadvantages imposed by the Identity Based Cryptography, we recommended using it along with the RSA algorithm. The proposed schemes were implemented in java and tested on an actual device, Nokia N70. In addition, we measured the time required by each of the algorithms we used to encrypt/decrypt a certain number of bytes. We found that the time taken by RSA and Blowfish algorithms will not be noticeable by the user. However, since the implementation of the Identity Based Cryptography we used was not meant to run on mobile devices, we encountered a noticeable delay whenever encrypting/decrypting the data using this algorithm. Securing the SMS messages will make it to be considered as one of the proposed means that could be used to conduct m-commerce. In addition, securing the MMS messages and the mobile content will increase the usability and the reliability of the mobile phones especially to the users on the move. / Phone: +46735731360

This thesis is focused on IEC 61850 communication protocols SMV, GOOSE and MMS and their implementation in SCADA systems. There is a simulator, run on Raspberry Pi, that generates data according to IEC 61850 and transmits the data using protocols in question. The simulation consist of various virtual devices e.g. surge protection, undervoltage protection, circuit breaker, disconnector, HMI. The MMS protocol is used for station control. Simulation can be user-defined from textual configuration file.

No description available.

Electrons accelerating in shock events occur oftenin outer space, for example in supernovas and the poles of blackholes, and are of high interest to physicists and other researchers.The technology to take a closer look at events that far awaydoes not exist yet, but luckily we can observe similar events inplaces where the Earth’s magnetic fields and particle streamsfrom the Sun meet. Using data from NASA’s MMS mission thispaper aims to gather information about what variables affect theacceleration, under what conditions the most energetic eventsoccur and create a ranked list of several hundreds of theseevents. It did this by calculating the expected value of the electrondistribution function at different times to create a dimensionlessranking. The study showed that these events are highly complexand that it is difficult to assign a few variables which would affectthe acceleration. However it also showed that most accelerationoccurs after the most abrupt shock crossing and not exactly atthe location where the expected value is maximal, and that thereare some correlations with angle relative to the solar magneticfield and electron number density. / Elektroner som accelereras i shockar skerofta i yttre rymden, till exmepel i supernovor och vid polernahos svarta hål, och är därför av högt intresse hos fysikeroch andra forskare. Teknologin för att titta närmre på dessafjärran fenomen existerar inte ännu, men som tur är så kan viobservera liknande händelser på platser där Jordens magnetfältmöter partikelvindar från Solen. Med hjälp av data från NASAsMMS uppdrag har detta projekt önskat att samla informationom vilka variabler som påverkar accelerationen, under vilkaomständigheter de mest energirika händelserna sker och skapa enrankad lista av flera hundra av dessa händelser. Det gjorde dettagenom att beräkna det förväntade värdet på elektronernas distributionsfunktionvid flera tillfällen för att skapa en dimensionslösrank. Studien visade att dessa händelser är mycket komplexaoch att det är svårt att tilldela ett fåtal variabler som skullepåverka accelerationen. Dock så visade projektet att den störstaaccelerationen sker efter den mest abrubta shockkorsningen ochinte exakt vid det tillfälle då det förväntansvärdet är som högst,och att det finns någon korrelation med vinkeln relativt solensmagnetfält och elektronernas nummerdensitet. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm

The GADD45 family of proteins consists of three small nuclear proteins, GADD45A, GADD45B, and GADD45G, which are implicated in modulating the cellular response to various types of genotoxic/physiological stress. This family of proteins has been shown to interact with and modulate the function of cell-cycle control proteins, such as p21 and cdc2/cyclin B1, the DNA repair protein, PCNA, key stress response MAP kinases, including MEKK4 (an upstream regulator of JNK kinase), and p38 kinase. Despite similarities in amino acid sequence, structure and function, each gadd45 gene is induced differentially, depending on the type of stress stimuli. For example, the alkylating agent, methylmethane sulfonate (MMS), rapidly induces all three genes, whereas hydrogen peroxide and sorbitol preferentially induce gadd45a and gadd45b, respectively. Studies of the mechanisms of the stress-mediated induction of the gadd45 genes have predominantly focused on gadd45a, with knowledge of gadd45b and gadd45g regulation lacking. Thus, in order to generate a more complete understanding of the collective regulation of the gadd45 genes, a comprehensive analysis of the stress-mediated induction of gadd45b has been carried out. Towards this end, a gadd45b promoter-reporter construct was generated, consisting of 3897bp sequence upstream of the transcription start site of gadd45b, fused to a luciferase reporter. In a human colorectal carcinoma cell line (RKO), in which gadd45b mRNA levels profoundly increase by various stress stimuli, we observe similar, high levels of induction of the gadd45b-luciferase construct with MMS or UVC treatments, but surprisingly not with sorbitol or anisomycin. Linker-scanning mutagenesis of the gadd45b promoter reveals several important MMS and UVC cis-acting responsive elements contained within the proximal promoter, including a GC-rich region and the CCAAT box. Furthermore, we have identified three constitutively bound transcription factors, Sp1, MZF1, and NFY, and one inducible factor, Egr1, which bind to these regions and which contribute to MMS-responsiveness. In contrast, a post-transcriptional mechanism appears to regulate gadd45b induction upon sorbitol treatment, as this treatment increases the gadd45b mRNA half-life, compared to MMS treatment. Interestingly, with the exception of a common cis-element, the stress-mediated induction of gadd45b appears to be mechanistically distinct from gadd45a. In conclusion, this study provides novel evidence that gadd45b induction by distinct stress agents, MMS and sorbitol, is regulated differentially at the level of mRNA transcription or mRNA stability, respectively. / Molecular Biology and Genetics

El control traduccional y la traducción selectiva de algunos mRNA representan un mecanismo regulador de las células para adaptarse a diversas condiciones fisiológicas y de estrés ambiental. En Saccharomyces cerevisiae la activación de la ruta de control traduccional GCN, cuyo transductor principal es la quinasa Gcn2p, favorece la adaptación a situaciones de estrés por falta de nutrientes. Gcn2p es activada por tRNA descargados durante condiciones de ayuno de aminoácidos. Gcn2p fosforila eIF2¿ (Sui2p) en ser51 y esto inhibe la traducción general de los mRNA, al mismo tiempo que permite la traducción selectiva de determinados mRNA que son necesarios para la supervivencia celular. Uno de ellos es el mRNA de GCN4, un factor de transcripción que regula genes de biosíntesis de amino ácidos entre otros. El pH intracelular modula la actividad de muchos sistemas celulares, pero los mecanismos de regulación y de percepción son en su mayoría desconocidos. Previamente en el grupo se ha identificado dos genes de S. cerevisiae importantes para la tolerancia a la acidificación intracelular causada por ácidos débiles permeables: LEU2 y GCN2. En la presente tesis se ha comprobado que LEU2, funciona eliminando la dependencia de la absorción de leucina extracelular en cepas con auxotrofia para este aminoácido. Además, se ha profundizado en los mecanismos moleculares por los cuales Gcn2p responde a pH ácido intracelular. La acidificación intracelular activa Gcn2p probablemente por la inhibición de las aminoacil-tRNA sintetasas porque se observa la acumulación de tRNAleu descargados en condiciones sin ayuno de leucina. Gcn2p es requerida para el transporte de leucina y un mutante nulo gcn2¿ es sensible al estrés ácido sí es auxótrofo para leucina y Gcn4p no se requiere para la tolerancia a ácido. Además un mutante ser51>ala en eIF2¿ es sensible a ácido, lo que sugiere que Gcn2p, mediante la fosforilación de eIF2¿, puede activar la traducción de un regulador desconocido de transportadores de aminoácidos distinto de Gcn4p. En relación al estrés genotóxico, evidencias previas muestran que Gcn2p está implicado en el control del ciclo celular en respuesta a daño al DNA regulando la transición de fase G1-S. Pero, ¿cómo ocurre esta respuesta de Gcn2p y qué efectores están implicados? Hemos descubierto que distintos agentes lesionantes del DNA activan la quinasa Gcn2p, entre ellos el agente alquilante MMS. Todos ellos de algún modo generan estrés replicativo. La caracterización genética con los mutantes de la ruta GCN muestra que Gcn1p/Gcn20p están implicados en la fosforilación de eIF2¿ por Gcn2p en respuesta a MMS. Además Gcn1p y Gcn2p puede tener un papel relacionado con la toxicidad por MMS independientemente del control traduccional. El rastreo de diversas proteínas de control de daño y/o de reparación del DNA muestra que las proteínas Xrs2p, Tel1p y Mag1p se requieren para la activación de Gcn2p provocada por MMS. Las dos primeras, actúan en una ruta de señalización y control de daño donde el complejo MRX es independiente del control traduccional. La activación de Gcn2p también es dependiente de la proteína de reparación codificada por MAG1 (3-metiladenina DNA glicosilasa), la cuál es necesaria para la reparación del DNA debido a daño causado por agentes alquilantes como MMS. En la respuesta a MMS mediada por el control traduccional parece estar implicado el complejo epistático RAD52. Por lo tanto, Gcn2p está conectado funcionalmente con la maquinaria de reparación y/o control de daño en el DNA. La activación de Gcn2p por MMS está mediada por la inhibición de ciertas aminoacil-tRNA sintetasas. De ellas, parece tener un papel relevante Frs2p, la subunidad ¿ de la fenilalanil-tRNA sintetasa citosólica. / Aparicio Sanchis, R. (2014). Nuevas funciones de Gcn2p en respuesta a estrés ácido y genotóxico [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/36067

Animal agriculture is a climate-exposed industry, creating the need to implement climate-smart manure management practices to alleviate manure's pollutive potential through greenhouse gas emissions (GHGe) and excess nutrient management. Manure management systems (MMS) require high initial investment for implementation and are often incentivized by cost-share programs that assume part of the implementation cost. The objective of Chapter 3 was to quantitatively summarize the literature on GHGe and manure nutrient composition in response to MMS use. Included studies provided data on the following: system size (L), species type, days stored, manure type (i.e. whole slurry, digestate, fractions, etc.), MMS type (anaerobic digestion, solid-liquid separation, covered and uncovered storage, composting systems, or mixed MMS use), and manure emissions and nutrient composition pre- and -post MMS use. The data were used to derive emissions coefficients and explore pollution reduction correlations between MMS with different pollution targets. A key takeaway is that there is inadequate data for MMS efficacy when used across species and location. This limits the accuracy of predictions made with the derived coefficients and limits the accuracy of which cost-share programs can be designed to achieve pollution reductions. Chapter 2 had the objective of exploring the strengths and weaknesses of cost-share programs. The complimentary analysis of historical cost-share data coupled with a stated-preference survey identified prioritization of MMS targeting GHGe as the most efficient and effective use of cost-share funding. The analysis also revealed that producer willingness to pay (WTP) has not changed over the decade, but that cost-share program structure should be equipped to account for higher pollution reduction prices while promoting MMS longevity. The pursuit of sustainability relies on the continuation of cost-share programs and MMS that focus on all facets of pollution reduction. / Master of Science / Livestock contribute to climate change by emitting greenhouse gas emissions (GHGe) and excess nutrients from their manure, impacting air and water quality. Manure management systems (MMS) further process manure for alternative uses while minimizing environmental harm. These systems are expensive and often require incentives for farmers to integrate them into their operations. Cost-share programs provide incentive by sharing a portion of MMS implementation cost. To ensure these programs utilize funding efficiently, agencies must be informed on the efficacy of each MMS and understand the influence different species manure and location can have on its performance. In response, our work aimed to identify the strengths and gaps within MMS literature and determine MMS ability to reduce pollution. Furthermore, we explored opportunities to improve existing cost-share programs, gauged the ability of MMS to maintain co-benefits between air and water quality reductions, and used current farmer perspectives to inform cost-share program structure. Towards that goal, a literature search of MMS efficacy was conducted, and studies were included if they provided data regarding MMS type (anaerobic digester, solid-liquid separation, composting, covered/uncovered storage, and mixed-system use), system size (L), species type, manure type (i.e. manure consistency and state), days stored, and the emissions or nutrient composition of manure before and after MMS use. A key finding from this work was that there is not enough data on MMS as they are used across species and location to accurately inform cost-share programs. Additionally, an analysis of historical cost-share data from the Department of Conservation and Recreation (DCR) and a survey gauging producer attitude about cost-share programs was also conducted. This work highlighted that MMS targeting GHGe or both pollution types should be implemented, and incentivizing those MMS may require more funding than before. To continue to combat climate change, current and accurate estimates of MMS capabilities are needed, and cost-share programs need to reorient focus towards implementing GHGe focused MMS or those addressing all areas of manure pollution.

La reconnexion magnétique est un processus omniprésent et fondamental dans la physique des plasmas spatiaux. La "Magnetospheric multiscale mission" (MMS) de la NASA, lancée le 12 mars 2015, a été conçue pour fournir des mesures in-situ permettant d'analyser le processus de reconnexion dans la magnétosphère terrestre. Dans ce but, quatre satellites identiquement instrumentés mesurent les champs électromagnétiques et les particules chargées dans les régions de reconnexion, avec une résolution temporelle cent fois meilleure que celle des missions précédentes. MMS permet, pour la première fois, d'étudier les structures microscopiques associées à la reconnexion magnétique et, en particulier, la région de diffusion électronique. Au niveau de la magnétopause terrestre, la reconnexion magnétique a un rôle chef dans le transport de l'énergie du vent solaire vers la magnétosphère terrestre, en convertissant l'énergie magnétique en énergie cinétique et thermique. Les événements à transfert de flux (FTEs) sont considérés comme l'un des produits principaux et les plus typiques de la reconnexion magnétique à la magnétopause terrestre. Cependant, des structures magnétiques 3D plus complexes, avec des signatures similaires à celles des FTEs, peuvent également exister à la magnétopause. On retrouve, par exemple, des tubes de flux entrelacés qui résultent de reconnexions magnétiques ayant eues lieu à des sites différents. La première partie de cette thèse étudie l'un de ces événements, qui a été observé dans des conditions de vent solaire inhabituelles, au voisinage de la magnétopause terrestre par MMS. Malgré des signatures qui, à première vue, semblaient cohérentes avec un FTE classique, cet événement a été interprété comme étant le résultat de l'interaction de deux tubes de flux avec des connectivités magnétiques différentes. La haute résolution temporelle des données MMS a permis d'étudier en détail une fine couche de courant observée à l'interface entre les deux tubes de flux. La couche de courant était associée à un jet d'ions, suggérant ainsi que la couche de courant était soumise à une compression qui a entraîné une reconnexion magnétique à l'origine du jet d'ions. La direction, la vitesse de propagation et la taille de différentes structures ont été déduites en utilisant des techniques d'analyse de données de plusieurs satellites. La deuxième partie de la thèse fournit une étude complémentaire à la précédente et s'intéresse aux ondes observées autour de la couche de courant. / Magnetic reconnection is a ubiquitous and fundamental process in space plasma physics. The NASA's Magnetospheric Multiscale mission (MMS) launched on 12 March 2015 was designed to provide in-situ measurements for analyzing the reconnection process at the Earth's magnetosphere. In this aim, four identically instrumented spacecraft measure fields and particles in the reconnection regions with a time resolution which is one hundred times faster than previous missions. MMS allows for the first time to study the microscopic structures associated with magnetic reconnection and, in particular, the thin electron diffusion region. At the Earth's magnetopause, magnetic reconnection governs the transport of energy and momentum from the solar wind plasma into the Earth's magnetosphere through conversion of magnetic energy into kinetic and thermal energies after a rearrangement of magnetic field lines. Flux Transfer Events (FTEs) are considered to be one of the main and most typical products of magnetic reconnection at the Earth's magnetopause. However, more complex 3D magnetic structures with signatures akin to those of FTEs might also occur at the magnetopause like interlaced flux tubes resulting from magnetic reconnection at multiple sites. The first part of the work presented in this thesis consisted of the investigation of one of these events that was observed, under unusual and extreme solar wind conditions, in the vicinity of the Earth's magnetopause by MMS. Despite signatures that, at first glance, appeared consistent with a classic FTE, this event was interpreted to be the result of the interaction of two separate sets of magnetic field lines with different connectivities. The high time resolution of MMS data allowed to resolve a thin current sheet that was observed at the interface between the two sets of field lines. The current sheet was associated with a large ion jet suggesting that the current sheet was submitted to a compression which drove magnetic reconnection and led to the formation of the ion jet. The direction, velocity and scale of different structures were inferred using multi-spacecraft data analysis techniques. This study was completed with a plasma wave analysis that focused on the reconnecting current sheet.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-04T19:04:18Z No. of bitstreams: 1 felipegomesduque.pdf: 1280593 bytes, checksum: 1f3d9c0ec3a41fa23d8f1844be3efc5c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T01:56:12Z (GMT) No. of bitstreams: 1 felipegomesduque.pdf: 1280593 bytes, checksum: 1f3d9c0ec3a41fa23d8f1844be3efc5c (MD5) / Made available in DSpace on 2016-04-24T01:56:12Z (GMT). No. of bitstreams: 1 felipegomesduque.pdf: 1280593 bytes, checksum: 1f3d9c0ec3a41fa23d8f1844be3efc5c (MD5) Previous issue date: 2016-07-19 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta um algoritmo baseado na técnica de otimização bio-inspirada denominada Monkey Search (MS) para alocação ótima de bancos de capacitores em sistemas de distribuição. O método proposto apresenta modificações e aprimoramentos da técnica MS para representar de forma adequada às características e restrições do problema de alocação de capacitores resultando em um novo algoritmo denominado Modified Monkey Search (MMS). O programa desenvolvido em MATLAB é utilizado para teste em diversos sistemas de distribuição. Os resultados obtidos apontam para um algoritmo com boa eficiência computacional. / This paper presents an algorithm based on bio-inspired optimization technique called Monkey Search (MS) for optimal allocation of capacitors in distribution systems. The proposed method presents modifications and enhancements of the MS technique to represent the characteristics and constraints of the problem related with capacitor allocation resulting in a new algorithm called Modified Monkey Search (MMS). The program developed in MATLAB is used to test multiple distribution systems. The results point to a computational efficient algorithm.

Collisionless shocks are widespread phenomena in the universe, and understanding the mechanisms behind their energy dissipation, with a rare number of collisions between particles, remains a significant unresolved question. The Earth’s bow shock provides an excellent opportunity to study this phenomena in situ. For high Mach number shocks, the shock cannot be sustained without partial reflection of the incoming ions. At higher Mach numbers, the shock surface starts to exhibit non-stationary behaviours, meaning that the shock surface starts evolving. One such behaviour is known as shock reformation, where a new shock forms upstream of an existing one. This study aims to investigate shock reformation using data obtained from NASA’s MMS mission, which offers precise measurements with high spatial and temporal resolutions through its constellation of four spacecraft. Using the MMS shocks database (Lalti et al., 2022), the gradient of the magnetic field magnitude is computed to infer non-stationary behaviour and identify potential instances of shock reformation and other shock behaviours. Through the analysis of the MMS measurements, some insight into the non-stationary characteristics of shocks is obtained using the gradient of the magnetic field. However, further analysis is needed in order to refine the method of identifying non-stationary behaviour of shocks, for future applications. / Kollisionsfria chocker är ett vanligt fenomen som förekommer i universum, och att förstå hur energidissipation inträffar i chocker med ett fåtal kollisioner mellan partikar är ett olöst problem. Jordens bogchock utger en bra möjlighet att studera detta på plats med mätningar från rymdfarkoster. Detta projekt försöker studera delar av jordens bogchock och undersöka dess dynamic. För chocker med högt machtal, måste en del av jonerna från solvinden reflekteras för att chocken ska skunna upprätthållas. Vid högre machtal kan chockytan visa icke-stationära beteenden, vilket innebär att den börjar förändras. Ett exempel på sådant beteende är chockreformation, där en ny chock formas framför en befintlig chock. Denna studie har som mål att undersöka chockreformation med hjälp av data som erhållits från NASA:s MMS-uppdrag, vilket erbjuder precisa mätningar med hög rumslig och tidsmässig upplösning genom sin konstellation av fyra rymdfarkoster. Genom användning av MMS-shockdatabasen (Lalti et al., 2022) beräknades gradienten av magnetfältets magnitud för att härleda icke-stationärt beteende och identifierade potentiella fall av chockreformation och andra beteenden. Genom analys av MMS-mätningarna erhölls viss insikt i de icke-stationära egenskaperna hos chocker med hjälp av gradienten av magnetfältet, men ytterligare analys krävs för att förbättra metoden för framtida tillämpningar.