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Implementace Digital Object Identifier na univerzitách v České republice: zkušenosti a doporučení / The implementation of Digital Object Identifier at the univerisities in Czech Republic: experience and recommendationsRumpíková, Kristina January 2019 (has links)
(in English): The aim of this thesis is to present persistent identification system of digital object identifier and analyze of use of DOI on a sample of public universities in the Czech Republic. The first part introduce the DOI system, its structure, advantages and examples of use in recent time. The second part is focused on analysis of current use of DOI in public univeristies. To fullfil this purpose researched questions were stated. Data was collected were determined in questionaire survey and semi structured interview. The conclusion of thesis proposes a direction of further reflection towards improvement of current situation.
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Algorithms for Multidimensional Persistence / Algoritmer för Multidimensionell PersistensGäfvert, Oliver January 2016 (has links)
The theory of multidimensional persistence was introduced in a paper by G. Carlsson and A. Zomorodian as an extension to persistent homology. The central object in multidimensional persistence is the persistence module, which represents the homology of a multi filtered space. In this thesis, a novel algorithm for computing the persistence module is described in the case where the homology is computed with coefficients in a field. An algorithm for computing the feature counting invariant, introduced by Chachólski et al., is investigated. It is shown that its computation is in general NP-hard, but some special cases for which it can be computed efficiently are presented. In addition, a generalization of the barcode for persistent homology is defined and conditions for when it can be constructed uniquely are studied. Finally, a new topology is investigated, defined for fields of characteristic zero which, via the feature counting invariant, leads to a unique denoising of a tame and compact functor. / Teorin om multidimensionell persistens introduserades i en artikel av G. Carlsson och A. Zomorodian som en generalisering av persistent homologi. Det centrala objektet i multidimensionell persistens är persistensmodulen, som representerar homologin av ett multifilterat rum. I denna uppsats beskrivs en ny algoritm för beräkning av persistensmodulen i fallet där homologin beräknas med koefficienter i en kropp. En algoritm för beräkning av karaktäristik-räknings-invarianten, som introducerade av Chachólski et al., utforskas och det visar sig att dess beräkning i allmänhet är NP-svår. Några specialfall för vilka den kan beräknas effektivt presenteras. Vidare definieras en generalisering av stäckkoden för persistent homologi och kraven för när den kan konstrueras unikt studeras. Slutligen undersöks en ny topologi, definierad för kroppar av karaktäristik noll, som via karaktäristik-räknings-invarianten leder till en unik avbränning.
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Persistentní identifikátory a jejich využití v digitálních knihovnách / Persistent identifiers and their use in digital librariesJílková, Marta January 2013 (has links)
The aim of this thesis is to present persistent identification systems and analysis of the use of persistent identifiers for digital objects on a sample of national digital libraries. The first part is a brief introduction to digital libraries. The second part describes selected permanent identification systems. The third part explains elements of selected national digital libraries. The last section is an analysis of the use of persistent identifiers in various national digital libraries. Keywords: persistent identifier, persistent identification system, URI, URN, PURL, Handle, DOI, ARK, digital library, national library, digital object
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Persistent Inward Currents Play a Role in Muscle Dysfunction Seen inMyotonia CongenitaHawash, Ahmed Alaa 28 July 2017 (has links)
No description available.
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The presence of persistent organic pollutants and heavy metals in sediment samples from rivers in the Kruger National Park / Annemarie van GessellenVan Gessellen, Annemarie January 2015 (has links)
Since 2008, large numbers of Nile crocodile (Crocodylus niloticus) carcasses were found in the
Kruger National Park (KNP), South Africa. Most of the crocodile carcasses were found in the Olifants
Gorge, which is situated below the Letaba and Olifants river confluence, before the Mozambique
border and Massingir Dam. The Massingir Dam is an important resource and it plays a significant
role in the welfare of the local Mozambican population.
Autopsies performed on the crocodiles indicated that the adipose tissue colour changed from normal
white to yellow and this is usually a sign of pansteatitis. Pansteatitis is caused by lipid peroxidation in
an organism and it is characterised by the lack of vitamin E. This disease is recognisable by the
hardening of the fatty tissue and yellow discolouration, and is mostly associated with aquatic
organisms from polluted ecosystems. There are speculations that the crocodile fatalities may be
associated with the Massingir Dam that backed up into the Olifants Gorge after flooding. After the
dam was reconstructed, it flooded the Olifants Gorge, causing it to act like a localised sediment trap
as the water flow slowed down and as a result, caused pollutants to build-up.
Sediment samples were collected from selected rivers and ponds within the KNP. These samples
were analysed for selected elements, persistent organic pollutants (POPs), and polycyclic aromatic
hydrocarbons (PAHs). The sediment samples were analysed in Norway for POPs and PAHs with the
use of a high-resolution gas chromatography/mass spectrometry (GC/MS) and the heavy metals were
analysed in South Africa with the use of inductively-coupled plasma mass spectrometry (ICP/MS).
In order to identify which elements may have affected the health of the crocodiles, a series of
sediment quality indices were used. These indices made it possible to determine which elements
may have been involved. The order of probability of heavy metals causing harm was
Se>As>Ni>Cr>Cu>I>V>Mn>Co>Fe>Cd>Hg>Zn>Pb>Ba>U.
The data was compared to selected international guidelines. All the information was used to
determine which of the sampled sites had the highest contamination. The sites sampled with the
highest concentrations were in the Crocodile, Nkomati, Olifants, and Letaba Rivers. Concentrations
of the elements, POPs, and PAHs were also quantifiable in the Olifants Gorge.
The following elements (Fe, Co, Cu, Cr, Pb, V, As, and Ni) were quantified at elevated levels and may
therefore have caused negative effects on the crocodiles in the Olifants Gorge. These elevated
concentrations, in combination with the dramatic change in the physical environment due to the dam,
could have added additional stress that may have contributed to the observed crocodile mortalities in
the Olifants Gorge. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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The presence of persistent organic pollutants and heavy metals in sediment samples from rivers in the Kruger National Park / Annemarie van GessellenVan Gessellen, Annemarie January 2015 (has links)
Since 2008, large numbers of Nile crocodile (Crocodylus niloticus) carcasses were found in the
Kruger National Park (KNP), South Africa. Most of the crocodile carcasses were found in the Olifants
Gorge, which is situated below the Letaba and Olifants river confluence, before the Mozambique
border and Massingir Dam. The Massingir Dam is an important resource and it plays a significant
role in the welfare of the local Mozambican population.
Autopsies performed on the crocodiles indicated that the adipose tissue colour changed from normal
white to yellow and this is usually a sign of pansteatitis. Pansteatitis is caused by lipid peroxidation in
an organism and it is characterised by the lack of vitamin E. This disease is recognisable by the
hardening of the fatty tissue and yellow discolouration, and is mostly associated with aquatic
organisms from polluted ecosystems. There are speculations that the crocodile fatalities may be
associated with the Massingir Dam that backed up into the Olifants Gorge after flooding. After the
dam was reconstructed, it flooded the Olifants Gorge, causing it to act like a localised sediment trap
as the water flow slowed down and as a result, caused pollutants to build-up.
Sediment samples were collected from selected rivers and ponds within the KNP. These samples
were analysed for selected elements, persistent organic pollutants (POPs), and polycyclic aromatic
hydrocarbons (PAHs). The sediment samples were analysed in Norway for POPs and PAHs with the
use of a high-resolution gas chromatography/mass spectrometry (GC/MS) and the heavy metals were
analysed in South Africa with the use of inductively-coupled plasma mass spectrometry (ICP/MS).
In order to identify which elements may have affected the health of the crocodiles, a series of
sediment quality indices were used. These indices made it possible to determine which elements
may have been involved. The order of probability of heavy metals causing harm was
Se>As>Ni>Cr>Cu>I>V>Mn>Co>Fe>Cd>Hg>Zn>Pb>Ba>U.
The data was compared to selected international guidelines. All the information was used to
determine which of the sampled sites had the highest contamination. The sites sampled with the
highest concentrations were in the Crocodile, Nkomati, Olifants, and Letaba Rivers. Concentrations
of the elements, POPs, and PAHs were also quantifiable in the Olifants Gorge.
The following elements (Fe, Co, Cu, Cr, Pb, V, As, and Ni) were quantified at elevated levels and may
therefore have caused negative effects on the crocodiles in the Olifants Gorge. These elevated
concentrations, in combination with the dramatic change in the physical environment due to the dam,
could have added additional stress that may have contributed to the observed crocodile mortalities in
the Olifants Gorge. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Dioxins and dioxin-like compounds in thermochemical conversion of biomass : formation, distribution and fingerprintsGao, Qiuju January 2016 (has links)
In the transition to a sustainable energy supply there is an increasing need to use biomass for replacement of fossil fuel. A key challenge is to utilize biomass conversion technologies in an environmentally sound manner. Important aspects are to minimize potential formation of persistent organic pollutants (POPs) such as dioxins and dioxin-like compounds. This thesis involves studies of formation characteristics of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and naphthalenes (PCNs) in microwave-assisted pyrolysis (MAP) and torrefaction using biomass as feedstock. The research focuses are on their levels, distributions, fingerprints (homologue profiles and isomer patterns) and the underlying formation pathways. The study also included efforts to optimize methods for extracting chlorinated aromatic compounds from thermally treated biomass. The overall objective was to contribute better understanding on the formation of dioxins and dioxin-like compounds in low temperature thermal processes. The main findings include the following: Pressurized liquid extraction (PLE) is applicable for simultaneous extraction of PCDDs, PCDFs, PCNs, polychlorinated phenols and benzenes from thermally treated wood. The choice of solvent for PLE is critical, and the extraction efficiency depends on the degrees of biomass carbonization. In MAP experiments PCDDs, PCDFs and PCNs were predominantly found in pyrolysis oils, while in torrefaction experiments they were mainly retained in solid chars with minor fractions in volatiles. In both cases, highly chlorinated congeners with low volatility tended to retain on particles whereas the less chlorinated congeners tended to volatize into the gas phase. Isomer patterns of PCDDs, PCDFs and PCNs generated in MAP were more selective than those reported in combustion processes. The presence of isomers with low thermodynamic stability suggests that the pathway of POPs formation in MAP may be governed not only by thermodynamic stabilities but also by kinetic factors. Formation of PCDDs, PCDFs and PCNs depends not only on the chlorine contents in biomass but also the presence of metal catalysts and organic/metal-based preservatives. Overall, the results provide information on the formation characteristics of PCDDs, PCDFs and PCNs in MAP and torrefaction. The obtained knowledge is useful regarding management and utilization of thermally treated biomass with minimum environmental impact.
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Constructing a Cyber Preparedness Framework (CPF): The Lockheed Martin Case StudyBeyer, Dawn Marie 01 January 2014 (has links)
The protection of sensitive data and technologies is critical in preserving United States (U.S.) national security and minimizing economic losses. However, during a cyber attack, the operational capability to constrain the exfiltrations of sensitive data and technologies may not be available. A cyber preparedness methodology (CPM) can improve operational capability and cyber security. The CPM enables a corporation to (a) characterize cyber threats; (b) determine the level of preparedness necessary to ensure mission success; (c) facilitate strategic planning for cyber security (CS); and (d) establish priorities for CS investment planning and management decisions. The cyber preparedness framework (CPF) underlies the CPM. A corporation's leadership articulates its fundamental approach to risk management (RM) and mission assurance, and determines its target level of preparedness. Typically, corporations utilize the CPF to (a) characterize the caliber of the threat; (b) assess the technical and operational capabilities to counter the threat; and (c) develop the governance and processes necessary to achieve its cyber preparedness level.
The problem that was investigated in this case study was how to construct a CPF for Lockheed Martin (LM) that works in conjunction with a risk management process (RMP). The goal was to extend the CPF into an RMP to construct a risk management framework (RMF) paradigm that can aid similarly large-sized private sector U.S. Government (USG) contractors in implementing the CPM. In this investigation, the author identified the corporate (a) security categorization, (b) cyber threats, (c) cyber threat level, (d) cyber preparedness level, (e) capabilities the corporation should utilize to counter cyber threats, and (f) governance and processes necessary to achieve the cyber preparedness level for a large-sized private sector USG contractor. The results of this investigation were organized in terms of RMP phases. Based on the results, the author constructed an RMF paradigm that can aid similarly large-sized USG contractors in implementing a CPM.
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Systems and applications for persistent memoryDulloor, Subramanya R. 07 January 2016 (has links)
Performance-hungry data center applications demand increasingly higher performance from their storage in addition to larger capacity memory at lower cost. While the existing storage technologies (e.g., HDD and flash-based SSD) are limited in their performance, the most prevalent memory technology (DRAM) is unable to address the capacity and cost requirements of these applications. Emerging byte-addressable, non-volatile memory technologies (such as PCM and RRAM) offer performance within an order of magnitude of DRAM, prompting their inclusion in the processor memory subsystem. Such load/store accessible non-volatile or persistent memory (referred to as NVM or PM) introduces an interesting new tier that bridges the performance gap between DRAM and PM, and serves the role of fast storage or slower memory. However, PM has several implications on system design, both hardware and software: (i) the hardware caching mechanisms, while necessary for acceptable performance, complicate the ordering and durability of stores to PM, (ii) the high performance of PM (compared to NAND) and the fact that it is byte-addressable necessitate rethinking of the system software to manage PM and the interfaces to expose PM to the applications, and (iii) the future memory-based applications that will likely employ systems coupling PM with DRAM (for cost and capacity reasons) must be extremely conscious of the performance characteristics of PM and the challenges of using fast vs. slow memory in ways that best meet their performance demands.
The key contribution of our research is a set of technologies that addresses these challenges in a bottom-up fashion. Since the real hardware is not yet available, we first implement a hardware emulator that can faithfully emulate the relative performance characteristics of DRAM and PM in a system with separate DRAM and emulated PM regions. We use this emulator to perform all of our evaluations. Next we explore system software support to enable low-overhead PM access by new and legacy applications. Towards this end, we implement PMFS, an optimized light-weight POSIX file system that exploits PM's byte-addressability to avoid overheads of block-oriented storage and enable direct PM access by applications (with memory-mapped I/O). To provide strong consistency guarantees, PMFS requires only a simple hardware primitive that provides software enforceable guarantees of durability and ordering of stores to PM. We demonstrate that PMFS achieves significant (up to an order of magnitude) gains over traditional file systems (such as ext4) on a RAMDISK-like PM block device.
Finally, we address the problem of designing memory-based applications for systems with both DRAM and PM by extending our system software to manage both the tiers. We demonstrate for several representative large in-memory applications that it is possible to use a small amount of fast DRAM and large amounts of slower PM without a proportional impact to an application's performance, provided the placement of data structures is done in a careful fashion. To simplify the application programming, we implement a set of libraries and automatic tools (called X-Mem) that enables programmers to achieve optimal data placement with minimal effort on their part. Finally, we demonstrate the potentially large benefits of application-driven memory tiering with X-Mem across a range of applications.
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Investigating the Role of Social Support, Cardiovascular Reactivity, and Self-Regulation Skills Training in Response to Thermal StimuliKniffin, Tracey Christine 01 January 2016 (has links)
Persistent pain conditions are a major health problem throughout the world and are one of the primary reasons that people seek medical treatment (Gureje, Von Korff, Simon, & Gater, 1998; Verhaak, Kerssens, Dekker, Sorbi, & Bensing, 1998). These conditions are characterized by complex interactions between cognitive, emotional, and physiological disturbances and are often associated with comorbid psychological disorders (Gatchel, 2004). Though previous studies have examined the effect of interventions targeting persistent pain, such as physical self-regulation interventions, few studies have examined the complex interaction between such interventions and other variables such as psychological and physiological functioning and presence of social support. The current study was designed to evaluate the effect of a physical self-regulation intervention (i.e. diaphragmatic breathing entrainment) on response to a brief physical stressor (i.e., mild thermal stimulation) as well as to evaluate whether presence or absence of a supportive partner influenced this relationship. Participant response was measured via self-report of pain intensity and unpleasantness and via physiological measures of respiration rate, blood pressure, heart rate, and heart rate variability. The study consisted of 154 female participants who participated in pairs (i.e., 77 pairs). Each participant was randomly assigned to training in diaphragmatic breathing or a control condition as well as being randomly assigned to complete the study with or without their supportive partner present. Analyses revealed that breathing entrainment resulted in significantly slower breathing rate during the thermal stressor task (p < .01). Presence of a supportive partner interacted with breathing entrainment to influence heart rate during the thermal stressor task (p < .05) such that participants who completed the study with a support person present had a lower heart rate when trained in diaphragmatic breathing than when trained in a control protocol and participants who did not have a support person present showed the opposite effect. Presence of a supportive partner also interacted with breathing entrainment to influence ratings of task unpleasantness (p < .05) such that participants who were trained in diaphragmatic breathing rated the task similarly regardless of presence or absence of a supportive partner, whereas participants who were trained in a control protocol rated the task as more unpleasant when accompanied by a supportive partner. In conclusion, the present study demonstrates the impact of training in diaphragmatic breathing and presence of social support on response to thermal stimuli as measured by both self-report (i.e., ratings of task unpleasantness) and physiological (i.e., respiration rate and heart rate) measures. This study highlights the usefulness of implementing a self-regulatory training strategy for treatment of pain and in considering the efficacy of incorporating a supportive partner into such training.
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