En nuestro país no es común el uso de la escoria de acero como sub producto para la elaboración de concreto, por este motivo el objetivo de esta investigación es mejorar la resistencia del concreto y la atenuación del paso de radiaciones ionizantes en los ambientes donde se hace uso de equipos que emiten radiación. El blindaje de los muros en los ambientes de radio diagnóstico esta normado por la Comisión Internacional de Protección Radiológica (ICRP) y el Instituto Peruano de Energía Nuclear (IPEN). Nuestra investigación es de tipo cuasi experimental, para lo cual se utilizó escoria de acero como agregado fino y grueso, fabricamos bloques cuadrados de concreto normal y concreto reemplazado en 30% y 50 % a los agregados fino y grueso por escoria de acero, las dimensiones de los bloques fueron de 30cm x30cm x10cm y 30cm x 30cm x5cm, los cuales fueron sometidos a exposición de rayos x. Los resultados demostraron que el concreto con el 30% con escoria y con 10 cm de espesor atenúa mejor el paso de los rayos X a una distancia de 5 cm del foco al bloque de concreto. Para los ensayos de resistencia a la compresión se elaboraron especímenes cilíndricos de 15cm de diámetro por 30cm de alto. En el desarrollo de la investigación se utilizó un concreto patrón de f’c = 280 kg/cm2 lográndose al final una resistencia a la compresión de 306.46 kg/cm2 con el concreto reemplazado al 30% de los agregados fino y grueso. / In our country it is not common to use steel slag as a by-product for the manufacture of concrete, for this reason the objective of this research is to improve the resistance of concrete and the attenuation of the passage of ionizing radiation in the environments where it is made. use of equipment that emits radiation. The shielding of the walls in radiodiagnosis environments is regulated by the International Commission for Radiological Protection (ICRP) and the Peruvian Institute of Nuclear Energy (IPEN). Our research is quasi-experimental, for which steel slag was used as fine and coarse aggregate, we manufacture square blocks of normal concrete and concrete replaced in 30% and 50% of fine and coarse aggregates by steel slag, the dimensions of the blocks were 30cm x30cm x10cm and 30cm x 30cm x5cm, which were subjected to x-ray exposure. The results showed that concrete with 30% slag and 10 cm thick better attenuates the passage of X-rays at a distance of 5 cm from the focus to the concrete block. For the compressive strength tests, cylindrical specimens of 15cm in diameter by 30cm high were made. In the development of the research, a standard concrete of f'c = 280 kg / cm2 was used, achieving at the end a compressive strength of 306.46 kg / cm2 with the concrete replaced at 30% of the fine and coarse aggregates. / Tesis

<p>U ovoj doktorskoj tezi razvijen je postupak za ispitivanje uticaja<br />oklopa na merni transformator bez jezgra sa stanovišta<br />linearnosti transformatora i zaštite transformatora od<br />uticaja elektromagnetske smetnje. Formiran je parametarski model<br />oklopa i mernog transformatora bez jezgra. Izvedena su merenja<br />magnetskih karakteristika feromagnetskih materijala, dat je novi<br />analitički model histerezisa i određene su krive magnetisanja i<br />permeabilnosti materijala. Na osnovu numeričkih i<br />eksperimentalnih rezultata, a u skladu sa definisanim<br />kriterijumom, izvršena je analiza kvaliteta oklapanja za<br />razmatrane tipove oklopa.</p> / <p>In this thesis a method for examining the effects of shielding on a coreless<br />measuring transformer from the standpoint of transformer linearity and EM<br />radiation shielding is developed. A parametric model of the shield and the<br />coreless measuring transformer is constructed. Measurements of magnetic<br />properties of ferromagnetic materials were performed; a new analytical model<br />of hysteresis is developed; magnetization curves and permeability of the<br />materials are determined. Based on numerical and experimental results, and<br />using the defined criterion, the analysis of shielding quality of the considered<br />shield types was performed.</p>

This thesis deals with the engineering of novel nanomaterials, particularly nanocomposites and nanostructured surfaces with enhanced functionalities. The study includes two parts; in the first part, an in situ sol-gel polymerization approach is used for the synthesis of polymer-inorganic hybrid material and its exceptional transparent UV-shielding effect has been investigated. In the second part, electrodeposition process has been adapted to engineer surfaces and the boiling performance of the fabricated nanostructured surfaces is evaluated. In the first part of the work, polymer-inorganic hybrid materials composed of poly(methylmethacrylate) (PMMA) and zinc compounds were prepared by in situ sol-gel transition polymerization of zinc complex in PMMA matrix. The immiscibility of heterophase of solid organic and inorganic constituents was significantly resolved by an in situ sol-gel transition polymerization of ZnO nanofillers within PMMA in the presence of dual functional agent, monoethanolamine, which provided strong secondary interfacial interactions for both complexing and crosslinking of constituents. In the second part of the work, nanoengineering on the surface of copper plates has been performed in order to enhance the boiling heat transfer coefficient. Micro-porous surfaces with dendritic network of copper nanoparticles have been obtained by electrodeposition with dynamic templates. To further alter the grain size of the dendritic branches, the nanostructured surfaces underwent a high temperature annealing treatment. Comprehensive characterization methods of the polymer-inorganic hybrid materials and nanoengineered surfaces have been undertaken. XRD, 1H NMR, FT-IR, TGA, DSC, UV-Vis, ED, SEM, TEM and HRTEM have been used for basic physical properties. Pool boiling tests were performed to evaluate the boiling performance of the electrodeposited nanostructured micro-porous structures. The homogeneous PZHM exhibited enhanced UV-shielding effects in the entire UV range even at very low ZnO content of 0.02 wt%. Moreover, the relationship between band gap and particle size of incorporated ZnO by sol-gel process was in good agreement with the results calculated from the effective mass model between bandgap and particle size. The fabricated enhanced surface has shown an excellent performance in nucleate boiling. At heat flux of 1 W/cm2, the heat transfer coefficient is enhanced over 15 times compared to a plain reference surface. A model has been presented to explain the enhancement based on the structure characteristics. / QC 20101118

The diploma thesis deals with shielding elements in the theoretical, project and experimental level. The theoretical part describes the variants of building shading and compares individual shading elements. It explains several concepts from the field of environmental technology, which are related to the topic. The design part deals with the air conditioning of the showroom space with a specific indoor environment. The space has a flush facade, so it has a high heat load. This is a showroom for veterans, where it is necessary to maintain optimal constant hu-midity throughout the year. An air conditioning unit was designed for these needs. The experimental part describes the measurement of the values of the shielding factor of external blinds for individual slopes of slats. The measurement results are applied to the reference room and the dependence between the inclination of the slats and the energy demand for space cooling is evaluated by the software.

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Achieving appropriate and natural backchanneling behavior in social robots remains a challenge in Human-Robot Interaction (HRI). This thesis addresses this issue by utilizing methods from Safe Reinforcement Learning in particular shielding to improve social robot backchanneling behavior. The aim of the study is to develop and implement a safety shield that guarantees appropriate backchanneling. In order to achieve that, a Recurrent Neural Network (RNN) is trained on a human-human conversational dataset. Two agents are built; one uses a random algorithm to backchannel and another uses shields on top of its algorithm. The two agents are tested using a recorded human audio, and later evaluated in a between-subject user study with 41 participants. The results did not show any statistical significance between the two conditions, for the chosen significance level of α &lt; 0.05. However, we observe that the agent with shield had a better listening behavior, more appropriate backchanneling behavior and missed less backchanneling opportunities than the agent without shields. This could indicate that shields have a positive impact on the robot’s behavior. We discuss potential explanations for why we did not obtain statistical significance and shed light on the potential for further exploration. / Att uppnå lämpligt och naturligt upbbackningsbeteende i sociala robotar är fortfarande en utmaning i Människa-Robot Interaktion (MRI). Den här avhandlingen tar upp detta problem genom att använda metoder från säker förstärkningsinlärning i synnerhet avskärmning för att förbättra sociala robotars upbbackningsbeteende. Syftet med studien är att utveckla och implementera en säkerhetsavskärmning som garanterar lämplig upbbackning. För att uppnå det, tränas ett återkommande neuralt nätverk på en människa-människa konversationsdatamängd. Två agenter byggs; en använder en slumpmässig algoritm för att upbbacka och en annan använder avskärmninng ovanpå sin algoritm. De två agenterna testas med hjälp av ett inspelat mänskligt ljud och utvärderas senare i en användarstudie med 41 deltagare. Resultaten visade inte någon statistisk signifikans mellan de två skicken, för den valda signifikansnivån &lt; 0, 05. Vi observerar dock att agenten med avskärmning hade ett bättre lyssningsbeteende, mer lämplig upbbackningsbeteende och missade mindre upbbacknings-möjligheter än agenten utan avskärmning. Detta kan indikera att avskärmning har en positiv inverkan på robotarnas beteende. Vi diskuterar potentiella förklaringar till varför vi inte fick statistisk signifikans och belyser potentialen för ytterligare utforskning.

Radiation shielding is a central part of the design of treatment rooms for radiation therapy systems. The dose levels that medical staff and members of the public can be exposed to outside the treatment rooms are regulated by authorities and influence the required wall thicknesses and possible locations for the systems. Several standard methods exist for performing shielding calculations, but they are not well adapted to the stereotactic radiosurgery system Leksell Gamma Knife because of its self-shielding properties. The built-in shielding makes the leakage radiation anisotropic and generally have lower energy than the primary radiation from the Gamma Knife's cobalt sources. Oversimplifications made in the standard shielding calculation methods regarding the field can lead to excessively thick shielding and limit the number of suitable locations for the system.  In this thesis project, a simulation-based dose calculation algorithm was developed, that uses Monte Carlo-generated data in two steps. The algorithm uses a phase space to accurately describe the radiation field around the Gamma Knife. Information about individual photons in the field is then combined with a generated library of data describing the resulting dose outside a wall depending on the wall thickness and the photon energy. The dose calculation algorithm is fast enough to be integrated into optimization processes, in which the algorithm is used iteratively while varying room design parameters. Demonstrated in this report is a case with a room of fixed size, in which the Gamma Knife's position and the walls' thicknesses are varied, with the aim to find the room design resulting in the minimum wall thicknesses needed to achieve acceptable dose levels outside. The results in this thesis indicate that the dose calculation algorithm performs well and could likely be used in more complex optimizations with more design variables and more advanced design goals. / Strålsäkerhet är en viktig aspekt vid uppförandet av behandlingsrum för strål-terapisystem. Strålningsnivåerna som sjukvårdspersonal och allmänheten kan exponeras för utanför behandlingsrummet regleras av myndigheter och påverkar vilken väggtjocklek som behövs och vilka platser som är lämpliga att placera systemen på. Flertalet metoder för strålskyddsberäkning existerar, men de är inte väl anpassade till det stereotaktiska radiokirurgiska systemet Leksell Gamma Knife, eftersom det har ett inbyggt strålskydd. Det inbyggda strålskyddet gör att strålfältet runt Gamma Knife är anisotropt och generellt har lägre energi än primärstrålningen från systemets koboltkällor. Förenklingar som görs rörande strålfältet i flera existerande metoder för strålskyddsberäkning kan leda till att överdrivet tjocka strålskydd används eller begränsa antalet lämpliga platser att placera systemet på. I detta projekt utvecklades en dosberäkningsalgoritm, som i två steg använder data genererad genom Monte Carlo-simuleringar. Algoritmen använder ett fasrum för att detaljerat beskriva strålfältet runt Gamma Knife. Information om enskilda fotoner i fältet används sen i kombination med ett genererat bibliotek av data som beskriver det dosbidrag som en foton bidrar med utanför behandlingsrummet, baserat på fotonens energi och väggarnas tjocklek. Dosberäkningsalgoritmen är snabb nog att integreras i optimeringsprocesser där den används iterativt samtidigt som rumsdesignparametrar varieras. I denna rapport demonstreras ett fall med ett rum av bestämd storlek, där positionen av Gamma Knife i rummet och väggarnas tjocklekar varieras. Optimeringens syfte i exemplet är att hitta den rumsdesign som med de minsta väggtjocklekarna resulterar i acceptabla strålningsnivåer utanför rummet. Resultaten tyder på att dosberäkningsalgoritmen sannolikt kan användas i mer komplexa optimeringar med fler designvariabler och mer avancerade designmål.

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In recent years, the enthalpy raise hot channel factor limit has decreased significantly due to the power upgrade of Ringhals 4 and the use of shielding fuel assemblies. The shielding fuel assemblies task are to reduce the neutron leakage to the reactor vessel and in that way extend the reactor lifetime. This is achieved by replacing a few fuel rods with steel rods. Experiences from the last fuel cycles show that the core design procedure has been hampered because of this and that it’s hard to stay under the design limit. A way to overcome this problem and to improve the fuel economy is to introduce the use of radial enrichment distribution in the fuel assembly. This master thesis shows, through a case study of three fuel cycles at Ringhals 4,  that the internal peaking factor can be improved by roughly 2–3 % and that the maximum enthalpy raise hot channel factor can be improved by about 2.0–2.5 % if the fuel assemblies contain three different levels of enrichments instead of currently one. This can be achieved without any noticeable decrease in cycle length. / Genom en fallstudie av tre driftcykler för Ringhals 4 visar den här rapporten att max FΔH under cykeln kan sänkas med 2,0–2,5 % om bränsleknippena radiellt anrikningsoptimeras med minst tre delanrikningar. Totalt under cykeln kan FΔH sänkas med upp till 4 %. Om radiell anrikningsoptimering införs för Vattenfalls PWR:er skulle arbetet med att designa härdarna förenklas och utrymme ges för att ladda reaktorerna på ett mer ekonomiskt sätt.