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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Functional investigation of arabidopsis long coiled-coil proteins and subcellular localization of plant rangap1

Jeong, Sun Yong 20 July 2004 (has links)
No description available.
82

Integrated Sensing and Communication in Cell-Free Massive MIMO / Integrerad avkänning och kommunikation i cellfri massiv MIMO

Behdad, Zinat January 2024 (has links)
Future mobile networks are anticipated to not only enhance communication performance but also facilitate new sensing-based applications. This highlights the essential role of integrated sensing and communication (ISAC) in sixth-generation (6G) and beyond mobile networks. The seamless integration of sensing and communication poses challenges in deployment and resource allocation. Cell-free massive multiple-input multiple-output (MIMO) networks, characterized by multiple distributed access points, offer a promising infrastructure for ISAC implementation. However, the effective realization of ISAC necessitates joint design and resource allocation optimization. In this thesis, we study ISAC within cell-free massive MIMO systems, with a particular emphasis on developing power allocation algorithms under various scenarios. In this thesis, we explore two scenarios: utilizing existing communication signals and incorporating additional sensing signals. We propose power allocation algorithms aiming to maximize the sensing performance while meeting communication and power constraints. In addition, we develop two maximum a posteriori ratio test (MAPRT) target detectors under clutter-free and cluttered scenarios. Results indicate that employing additional sensing signals enhances sensing performance, particularly in scenarios where the target has low reflectivity. Moreover, although the clutter-aware detector requires more advanced processing, it leads to better sensing performance. Furthermore, we introduced sensing spectral efficiency (SE) to measure the effect of resource block utilization, highlighting the integration advantages of ISAC over orthogonal resource sharing approaches.  In the next part of the thesis, we study the energy efficiency aspects of ISAC in cell-free massive MIMO systems with ultra-reliable low-latency communications (URLLC) users. We propose a power allocation algorithm aiming to maximize energy efficiency of the system while meeting communication and sensing requirements. We conduct a comparative analysis between the proposed power allocation algorithms and a URLLC-only approach which takes into account only URLLC and power requirements. The results reveal that while the URLLC-only algorithm excels in energy efficiency, it is not able to support sensing requirements.   Moreover, we study the impact of ISAC on end-to-end (including radio and processing) energy consumption. Particularly, we present giga-operations per second (GOPS) analysis for both communication and sensing tasks. Two optimization problems are formulated and solved to minimize transmission and end-to-end energy through blocklength and power optimization. Results indicate that while end-to-end energy minimization offers substantial energy savings, its efficacy diminishes with sensing integration due to processing energy requirements. / Framtida mobila nätverk förväntas inte bara förbättra kommunikations-prestanda utan även mögliggöra nya applikationer baserade på sensorer. Dettaunderstryker den avgörande rollen för Integrerad avkänning och kommunika-tion (ISAC) i sjätte generationens (6G) och efterföljande mobila nätverk. Densömlösa integrationen av sensorer och kommunikation medför utmaningar iutrullning och resursallokering. Cellfria massiva flerantennsystem (MIMO-nätverk), kännetecknade av flera distribuerade åtkomstpunkter, erbjuder enlovande infrastruktur för implementering av ISAC. Dock kräver den effektivarealiseringen av ISAC samverkande design och optimering av resursallokering.I denna avhandling studerar vi ISAC inom cellfria massiva MIMO-system,med särskild tonvikt på att utveckla effektallokeringsalgoritmer under olikascenarier.Vi utforskar två scenarier: att utnyttja befintliga kommunikationssignaleroch att inkludera ytterligare sensorssignaler. Vi föreslår effektallokeringsalgo-ritmer med målet att maximera sensorsprestandan samtidigt som kommunika-tions och effektbegränsningar uppfylls. Dessutom utvecklar vi två detektorerbaserade på maximum a posteriori ratio test (MAPRT) under störningsfriaoch störda scenarier. Resultaten visar att användning av ytterligare sensors-signaler förbättrar sensorsprestandan, särskilt i scenarier där målet har lågreflektivitet. Dessutom, även om den störkänsliga detektorn kräver mer avan-cerad bearbetning, leder den till bättre sensorsprestanda. Vidare introducerarvi sensorerspektral effektivitet (SE) för att mäta effekten av resursblocksan-vändning och framhäva integrationsfördelarna med ISAC över ortogonala re-sursdelningsmetoder.I den andra delen av avhandlingen studerar vi energieffektivitetsaspek-terna av ISAC i cellfria massiva MIMO-system med användare med ultra-tillförlitlig låg-latens (URLLC) kommunikation. Vi föreslår en effektalloke-ringsalgoritm med syfte att maximera systemets energieffektivitet samtidigtsom kommunikations- och sensorskraven uppfylls. Vi utför en jämförande ana-lys mellan de föreslagna effektallokeringsalgoritmerna och ett URLLC-ensamttillvägagångssätt som tar hänsyn enbart till URLLC- och effektkrav. Resul-taten avslöjar att medan URLLC-ensamma algoritmen utmärker sig i energi-effektivitet, kan den inte stödja sensorskraven. Dessutom studerar vi effektenav ISAC på slut till slut (inklusive radios och bearbetning) energiförbruk-ning. Särskilt presenterar vi giga-operationer per sekund (GOPS) analys förbåde kommunikations- och sensorsuppgifter. Två optimeringsproblem formu-leras och löses för att minimera överförings- och slut till slut energi genomblocklängd- och effektoptimering. Resultaten indikerar att medan slut till slutenergiminimering erbjuder betydande energibesparingar, minskar dess effek-tivitet med sensorintegrationen på grund av bearbetningsenergikrav. / <p>QC 20240513</p>
83

Optimizing the Fronthaul in C-RAN by Deep Reinforcement Learning : Latency Constrained Fronthaul optimization with Deep Reinforment Learning / Optimering av Fronthaul i C-RAN med Djup Förstärknings Inlärning : Latens begränsad Fronthaul Optimering med Djup Förstärknings Inlärning

Grönland, Axel January 2023 (has links)
Centralized Radio Access Networks or C-RAN for short is a type of network that aims to centralize perform some of it's computation at centralized locations. Since a lot of functionality is centralized we can show from multiplexing that the centralization leads to lower operating costs. The drawback with C-RAN are the huge bandwidth requirements over the fronthaul. We know that scenarios where all cells experience high load is a very low probability scenario. Since functions are centralized this also allows more adaptability, we can choose to change the communication standard for each cell depending on the load scenario. In this thesis we set out to create such a controller with the use of Deep Reinforcement Learning. The problem overall is difficult due to the complexity of modelling the problem, but also since C-RAN is a relatively new concept in the telecom world. We solved this problem with two traditional reinforcement learning algorithms, DQN and SAC. We define a constraint optimization problem and phrase it in such a way that the problem can be solved with a deep reinforcement learning algorithm. We found that the learning worked pretty well and we can show that our trained policies satisfy the constraint. With these results one could show that resource allocations problems can be solved pretty well by a deep reinforcement learning controller. / Centralized Radio Access Networks eller C-RAN som förkortning är en kommunications nätverk som siktar på att centralisera vissa funktioner i centrala platser. Eftersom mmånga funktioner är centraliserade så kan vi visa från statistisk multiplexing att hög trafik scenarion över många celler är av låg sannolikhet vilket leder till lägre service kostnader. Nackdelen med C-RAN är den höga bandbredds kravet över fronthaulen. Trafik scenarion där alla celler utsäts för hög last är väldigt låg sannolikhet så kan vi dimensionera fronthaulen för att klara mindre än det värsta trafik scenariot. Eftersom funktioner är centralizerade så tillåter det även att vi kan adaptivt anpassa resurser för trafiken. I denna uppsats så kommer vi att skapa en sådan kontroller med djup reinforcement learning. Problemet är komplext att modellera och C-RAN är ett relativt nytt concept i telecom världen. Vi löser detta problem med två traditionella algoritmer, deep Q networks(DQN) och soft actor critic(SAC). Vi definierar ett vilkorligt optimerings problem och visar hur det kan formuleras som ett inlärnings problem. Vi visar att denna metod funkar rätt bra som en lösning till problemet och att den uppfyller bivilkoren. Våra resultat visar att resurs allokerings problem kan lösas nära optimalitet med reinforcement learning.
84

Strukturně- a sekvenčně-závislá identifikace funkčně významných aminokyselin v proteinové rodině. / Structure- and sequence-based identification of functionally important amino acids in a protein family

Peclinovská, Iveta January 2015 (has links)
A group of small GTPases consist of over twenty protein families in the super class P-loop. It has a very diverse cell functions. Small GTPases regulate the formation of vesicular follicles, cytoskeleton and nuclear transport. They participate also on cell proliferation and signaling. The aim of my work is to find important amino acids that define family and distinguish each other. I focus on families Arf, Rab, Ran, Ras and Rho. At the Rho family I am also devoted to classes Rho, Rac and Cdc42. Amino acids are identified using bioinformatic programs selected Consurf and Sca5. The objective is also to test P2RANK specialized tool developed at the Charles University in Prague that predict ligand binding sites from protein structure in different families. Founding amino acids can have a big role in the functional divergence of individual families and classes of small GTPases and can be the basis for future study example for the proliferation of cancerous cells. 1.1 Keywords Powered by TCPDF (www.tcpdf.org)
85

Radio resource management techniques for multi-tier cellular wireless networks

Abdelnasser, Amr Adel Nasr 06 1900 (has links)
There is a prolific increase in the penetration of user devices such as smartphones and tablets. In addition, user expectations for higher Quality of Service (QoS), enhanced data rates and lower latencies are relentless. In this context, network densification through the dense deployment of small cell networks, underlaying the currently existing macrocell networks, is the most appealing approach to handle the aforementioned requirements. Small cell networks are capable of reusing the spectrum locally and providing most of the capacity while macrocell networks provide a blanket coverage for mobile user equipment (UEs). However, such setup imposes a lot of issues, among which, co-tier and cross-tier interference are the most challenging. To handle co-tier interference, I have proposed a semi-distributed (hierarchical) interference management scheme based on joint clustering and resource allocation (RA) for small cells. I have formulated the problem as a Mixed Integer Non-Linear Program (MINLP), whose solution was obtained by dividing the problem into two sub-problems, where the related tasks were shared between the Femto Gateway (FGW) and small cells. As for cross-tier interference, I have formulated RA problems for both the macrocell and small cells as optimization problems. In particular, I have introduced the idea of ``Tier-Awareness'' and studied the impact of the different RA policies in the macrocell tier on the small cells performance. I have shown that the RA policy in one tier should be carefully selected. In addition, I have formulated the RA problem for small cells as an optimization problem with an objective function that accounts for both RA and admission control (AC). Finally, I have studied cloud radio access network (C-RAN) of small cells which has been considered as a typical realization of a mobile network which is capable of supporting soft and green technologies in Fifth Generation (5G) networks, as well as a platform for the practical implementation of network multiple-input multiple-output (MIMO) and coordinated multi-point (CoMP) transmission concepts. / February 2016
86

Ošetřovatelská péče o rány v Namibii, Irsku a České republice / Wound care in Namibia, Ireland and the Czech republic

FRANKOVÁ, Šárka January 2015 (has links)
Wound care is an important part of the daily work of nurses in all facilities like hospitals, institutes for long-term patients, social care institutions, or ambulances. In recent years, the treatment of wounds puts more and more emphasis on modern methods, mainly in the Czech Republic (CR) and Ireland. As already mentioned, nursing is constantly evolving, and possibilities for wound treatment are wide. Our aim will be to compare the ways and methods of wound treatment in three different countries. We will focus on the General Nurse, as a nursing care provider. In the theoretical part, the work was focused on characteristic of wounds, their distribution, general healing as well as concrete treatment in the countries concerned, specifically according to the competence of nurses. A major part was devoted to the education of nurses The main purpose of the research was focused on the way nurses treat wounds in Namibia, Ireland and the Czech Republic. Based on the research subject the following research questions and goals were set: Identify and describe how nurses treat wounds in the selected countries. How are wounds healed in Namibia, Ireland and the Czech Republic? How is the wound care in Namibia, Ireland and the Czech Republic? What kind of education does a nurse have to have in the countries concerned, in connection with the wound care? For the empirical part of the thesis, a qualitative approach was selected. A semi-structured interview with nurses from the selected countries was used. Further records of the wound treatment were used. These were obtained during the internship in Namibia, a personal visit to Ireland and my experience during my studies in the Czech Republic. Respondents were recruited by purposive sampling, the condition of which was wound care requiring hospital treatment. The interviews were conducted using a range of questions addressing nurses in those countries during their working hours and if needed, supplementing the required information via Skype. The research sample consisted of nine respondents - nurses from Namibia, Ireland and the Czech Republic and then records of the wound treatment of 9 patients from Namibia, the Czech Republic and Ireland were drawn. The countries have their competencies relating to this issue. In Ireland, Czech Republic there is a re-bandaging nurse, who creates a nursing plan and, if needed, consults everything with the physician. In Namibia, due to lack of nurses and physicians, only competences of local nurses which they acquired during their university studies, are sufficient. These competences lead to decisions and choice of care and wound treatment. In the Czech Republic, nurses shall consult the healing process and the course of treatment with the physician. In the area of education of nurses from the surveyed countries in connection with wound care the research investigation showed that university education is required in Namibia, in the Czech Republic as well as in Ireland. The third mentioned research question related to methods of care with clients suffering from acute or chronic wounds. Wound care in Namibia, Ireland, and in the Czech Republic does not differ in some specific procedures; however, in most cases it is very different. In severe cases of wounds, for many patients it is an unforgettable memory, which requires a professional approach, consisting of knowledge and experience. The nurse provides a unique support to the patient, education is therefore very important and unconditional in order to enable the patient coping with the situation. The results of this thesis can serve as information and study material to other grades of the surgical block and for further research on a similar topic.
87

5G Simulation Framework

Olsson, Joel, Asante, Junior January 2018 (has links)
From the first generation, 1G, to the fourth generation, 4G, the development and technological advancements in telecommunications network systems have been remarkable. Faster and better connections have opened up for new markets, ideas and possibilities, to that extent that there now is a demand that surpasses the supply. Despite all these advancements made in the mobile communications field most of the concept of how the technology works and its infrastructure has remained the same. This however, is about to change with the introduction of the fifth generation (5G) mobile communication. With the introduction of 5G much of the technology introduced will be different from that of previous generations. This change extends to include the entire infrastructure of the mobile communications system. With these major changes, many of the tools available today for telecommunications network evaluation do not really suffice to include the 5G network standard. For this reason, there is a need to develop a new kind of tool that will be able to include the changes brought by this new network standard. In this thesis a simulation framework adapted for the next generation telecommunication standard 5G is set to be developed. This framework should include many of the characteristics that set 5G aside from previous generations.
88

Nutriční stav pacientů trpících hlubokou dehiscencí sternotomické rány / Nutritional status in patients suffering from deep sternal wound infection

Štroblová, Petra January 2017 (has links)
Introduction: The procedure of longitudinal median sternotomy is the most commonly used approach in cardiac surgery with the necessary complex postoperative treatment. A multifactorial approach is particularly important to prevent later complications, which can be very serious or fatal. The theoretical part of the thesis is not just about the risk factors that may interfere with the healing process but also about nutritional measures that could reduce the risk or completely prevent the profound dehiscence of the sternotomic wound. Methodology: The research method consisted of a retrospective analysis of the risk factors of deep sternal dehiscence in 22 patients who underwent cardiac surgery using the technique of longitudinal median sternotomy over a ten-year interval. 11 patients with sternal healing disorder were selected and included in group 1. Subsequently, an additional 11 patients were selected without sternal dehiscence. These patients were selected in such a way that their characteristics corresponded to the characteristics of patients of the first group in terms of statistical evaluation and comparison of both groups (type of exercise, length of operation, use of extracorporeal circulation, LIMA / BIMA, etc.). In the selection of patients in the control group 2, the laboratory nutrition...
89

Vývoj a příprava antimikrobiálních nanostrukturních biomateriálů / Development and preparation of antimcrobial nanostructure biomaterials

Drabíková, Nela January 2021 (has links)
The presented diploma thesis deals with the optimalisation of preparation and the preparation of combined nanostructured antimicrobial biomaterials itself. In the theoretical part, a review focused on used materials and consequently preparation of nanoparticles and nanofibers was elaborated. Furthermore, the used antimicrobial substances – curcumin and ampicillin, and the principle of cytotoxicity assay were described.In practical part the optimalisation process is described. Furthermore the safety of prepared materials and used antimicrobial substances on HaCaT cell line was tested, in order to confirm their possible further use in cosmetic and pharmaceutical industry. Great part of the thesis deals with evaluation of the antimicrobial activity of used substances and prepared combined nanomaterials on multiple microorganisms from grampositive bacteria, gramnegative bacteria and yeasts. Also the release speed of antimicrobial substances from prepared nanomaterials was determined by spectrophotometer. The amount of released ampicillin from prepared nanomaterials was determined by liquid chromatography.
90

Slice-Aware Radio Resource Management for Future Mobile Networks

Khodapanah, Behnam 05 June 2023 (has links)
The concept of network slicing has been introduced in order to enable mobile networks to accommodate multiple heterogeneous use cases that are anticipated to be served within a single physical infrastructure. The slices are end-to-end virtual networks that share the resources of a physical network, spanning the core network (CN) and the radio access network (RAN). RAN slicing can be more challenging than CN slicing as the former deals with the distribution of radio resources, where the capacity is not constant over time and is hard to extend. The main challenge in RAN slicing is to simultaneously improve multiplexing gains while assuring enough isolation between slices, meaning one of the slices cannot negatively influence other slices. In this work, a flexible and configurable framework for RAN slicing is provided, where diverse requirements of slices are taken into account, and slice management algorithms adjust the control parameters of different radio resource management (RRM) mechanisms to satisfy the slices' service level agreements (SLAs). A new entity that translates the key performance indicator (KPI) targets of the SLAs to the control parameters is introduced and is called RAN slice orchestrator. Diverse algorithms governing this entity are introduced, which range from heuristics-based to model-free methods. Besides, a protection mechanism is constructed to prevent the negative influences of slices on each other's performances. The simulation-based analysis demonstrates the feasibility of slicing the RAN with multiplexing gains and slice isolation.

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