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Obtaining an accurate whole program path (WPP) that captures a program’s runtime behaviour in terms of a control-flow trace has a number of well-known benefits, including opportunities for code optimization, bug detection, program analysis refinement, etc. Existing techniques to compute WPPs perform sub-optimal instrumentation resulting in significant space and time overheads. Our goal in this thesis is to minimize these overheads without losing precision. To do so, we design a novel and scalable whole program analysis to determine instrumentation points used to obtain WPPs. Our approach is divided into three components: (a) an efficient summarization technique for inter-procedural path reconstruction, (b) specialized data structures called conflict sets that serve to effectively distinguish between pairs of paths, and (c) an instrumentation algorithm that computes the minimum number of edges to describe a path based on these conflict sets. We show that the overall problem is a variant of the minimum hitting set problem, which is NP-hard, and employ various sound approximation strategies to yield a practical solution. We have implemented our approach and performed elaborate experimentation on Java programs from the DaCapo benchmark suite to demonstrate the efficacy of our approach across multiple dimensions. On average, our approach necessitates instrumenting only 9% of the total number of CFG edges in the program. The average runtime overhead incurred by our approach to collect WPPs is 1.97x, which is only 26% greater than the overhead induced by only instrumenting edges guaranteed to exist in an optimal solution. Furthermore, compared to the state-of-the-art, we observe a reduction in runtime overhead by an average and maximum factor of 2.8 and 5.4, respectively.

In eubacteria, ribosome stalling on broken messenger RNA transcripts can lead to cell death. The trans-translation quality control mechanism rescues many of these stalled ribosomes. In this process, tmRNA enters stalled ribosomes by mimicking a transfer RNA, accepting the stalled nascent peptide. The ribosome then releases the broken mRNA and resumes translation on a coding region within tmRNA itself. Translation of tmRNA marks the nascent peptide for destruction by the addition of a short proteolysis tag and the ribosome is released at a stop codon within the tmRNA open reading frame. An intriguing aspect of trans-translation is that the ribosome synthesizes one protein from two RNA templates. How is the proper site chosen on tmRNA to resume translation? Do the conserved pseudoknot structures help set the reading frame? Using a genetic selection to assay libraries of tmRNA mutants, we found that stable hairpin structures can functionally replace pseudoknot 1. We conclude that the role of pseudoknot 1 in tmRNA function is purely structural. Our results demonstrate that the inactivity of an RNA mutant designed to destroy a given structure should not be interpreted as proof that the structure is necessary for RNA function. Such mutations may only destabilize a global fold that could be formed equally well by an entirely different, stable structure. Broken mRNAs are not the only cause of ribosome stalling; stalling can also result from nascent peptide interactions with the ribosomal exit tunnel that inhibit peptidyl-transferase activity. SecM, TnaC, and ErmCL all stall ribosomes to regulate the expression of downstream genes. What other peptide sequences can cause ribosome stalling? We modified our tmRNA-based selection to screen libraries of random peptides and identified a number of novel stalling peptides, including the sequence FxxYxIWPP. This sequence interacts with the exit tunnel differently than SecM and TnaC as seen in studies using mutant ribosomes. Like SecM, stalling occurs on this sequence with the next aminoacyl tRNA trapped in the A site but unable to react with the nascent peptide. These results show that a variety of peptides can interact in the exit tunnel and peptidyl-transferase center to regulate ribosome activity.

This thesis examines a gender quota in Algeria to determine if signs can be found that it was adopted to improve the regime’s image, rather than to empower women. Such symbolic gender reforms are also known as autocratic gender-washing and are problematic as they are generally viewed as democratisation efforts but have no such effect. In the case of autocratic gender-washing neither democracy nor women benefit as it only serves to legitimate an authoritarian regime. This thesis has a feminist institutionalist analytical perspective which serves to understand the gendered nature of institutions, the relationship between formal and informal institutions, and how they undergo change. There is also an assumption that descriptive representation should lead to substantive representation for gender quotas to be successful. The case of Algeria is chosen as it is considered an authoritarian regime but implemented a relatively drastic gender quota at 30% reserved seats, which they abolished after only ten years, in 2021. Women’s issues in Algeria are examined to better understand what benefits women as a group prioritised. This contextualisation reveals what topics to analyse to reveal genuine gender reform or autocratic gender-washing. A critical discourse analysis is conducted to find signs of whether the quota benefitted women as well as if the regime was given credit for it. The thesis finds that there are signs of autocratic gender-washing but also cautious suggestions of women benefitting from reform through adjusted policy design.

The thesis deals with the principle functions of low-temperature fuel cells with proton exchange membrane (PEMFC), photovoltaic sources (PVPP) and wind energy sources (WPP), along with solving their detailed mathematical expressions. In this work, the individual sources and their simulated models are analyzed in depth. The actual simulation is preceded by familiarization with important historical milestones in the development of fuel cells. Furthermore there is a basic classification of fuel cells and the characteristics of the cells used in the energy sectors. The text also provides information on projects that address the implementation of PEMFC as a primary or supplementary source of energy. Along with outlining the options for PEMFC as a perspective hydrogen technologies in the near future, the basic methods of hydrogen production and storage options are presented for the complexity. The work is exclusively focused on improving PEMFC mathematical models that under the hybrid system cooperate with renewable energy sources (RES). Part of the theses contains a short review of run or modeled concepts of hybrid systems in the energy sector. Using these models the main deficiencies of the models or of the whole PEMFC system can be identify. Specifications of the deficiencies lead to the creation of a new advanced dynamic PEMFC model that allows an analysis of the development of electrical and non-electrical quantities using long term tests. Furthermore, the thesis presents results of the experiments of thermal and dynamic behavior PEMFC, which were obtained from the additionally extended model with a reformer and the DC/DC converter. In this text there is a model of a photovoltaic module created, which is based on the nominal values parameterization. The model is subjected to basic experiments in which measured hydrometeorological data are used. If the hybrid system utilizes renewable energy sources, it is good to know the evolution of atmospheric conditions in the installation of these resources. Specifically for PVPP, publicly available databases containing information about solar radiation levels can be used for the selected location. Public databases are often used for initial design and manufacturing options for PVPP. An evaluation of the relevancy of public databases is performed based on a long-term observation of real measured data. Furthermore, these data are used for experiments on the photovoltaic module. Partially the text addresses the issue of the wind energy sources, however, it is simulated only on a simplified model of WPP. Created models of subsystems can be generally implemented as partial inputs hybrid systems in the future work. The thesis was developed at Centre for Research and Utilization of Renewable Energy (CVVOZE) with the financial support of the National Programme for Sustainability and the Ministry of Education, Youth and Sports of the Czech Republic under the project no. LO1210 - Energy for Sustainable Development and the project no. FEKT-S-14-2520 - New Technologies for Sustainable Development of Electrical Power Systems. The thesis was also generated under the project no. TA03020523 - Dynamic model of distribution network with the financial support of Technology Agency of the Czech Republic.