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<p> Design and optimization of aircraft thermal management systems (TMS) is typically conducted by considering a single system architecture at steady-state conditions, using per?formance metrics such as bleed air flow rate, fuel burn flow rate, or total system mass. However, when trying to increase the overall performance of a legacy system or analyzing new system architectures, it can be difficult to identify how individual component or sub?system changes will propagate throughout the overall TMS. In this thesis, new knowledge and tools are presented that will advance the use of exergy-based design techniques for next generation aircraft thermal management systems (TMS). This is motivated by the fact that exergy destruction is a quantity that can be calculated for any subsystem or component, regardless of energy domain or function. The relationship between exergy destruction min?imization (EDM) and conventional design metrics is investigated and quantified. This is performed through the use of a steady-state analysis and by leveraging a high fidelity model of a complex TMS. It is shown that exergy destruction is not only sensitive to individual component parameters in a manner consistent with conventional performance metrics, but that due to its generalizability, it also captures how changes in one subsystem propagate throughout the overall TMS. Specifically, through a design case study, it is shown that minimizing system-wide exergy destruction rate (without an engine model) yields a similar engine fuel burn rate as when fuel burn is minimized directly, but also results in a signif?icantly lower system mass. Building on these results, a transient design and analysis tool for TMS is developed using a graph theoretic approach. The tool is used on a case study of an air cycle machine (ACM) and on an architecture enumeration case study for a notional TMS. The transient exergy-based analysis is shown to provide insight into how efficiently energy is used at a component level, and captures the differences in thermal performance between architectures. </p>

E-handelslösningar tillhandahåller inköpsfunktioner för användare på produkter online, men Internetanvändare är känsliga för förseningar. Användare ser webbplatsens laddningstid egenskap. Användarna är även känsliga för kognitiv laddningstid, vilket har att göra med upplevda estetik av en webbplats och mentala modeller som skapas från tidigare interaktion med webbplatser. Omfattningen av examensarbetet är att fyra e-handels content management system (CMSs) jämförs i denna avhandling att se vilka utför med den lägsta sidan laddningstid. dessa är Magento, Drupal med commerce, Wordpress med woocommerce och Joomla med Hikashop. Alla CMS förvandlas till liknande design baserat på en universell tema, med hjälp av twitter bootstrap ramverket. Designen är baserad på tidigare forskning för användarnas mentala modeller för e-handel webbplatser. En fullt fungerande fiktiv plats Fastcommerce utvecklas på dessa fyra CMS. CMSn är fyllda med en kategori sida identiska prov elektroniska produkter (12 artiklar). Produkterna har bilder och lorem ipsum text. Metoden för examensarbetet är experiment. Experimenten utförs för att hitta den sida laddningstid på en lokal miljö. Resultaten visar tydliga resultatförbättringar på alla fyra CMSs efter tillämpade optimeringar. Men några av de optimeringar orsakar negativakonsekvenser prestanda. / E-commerce solutions are providing purchasing capabilities to users on products online, but Internet users are sensitive to delays. In-fact users see page load time as a website feature. Users are also sensitive to cognitive load time, which has to do with perceived aesthetics of a website and mental models which are created from previous interaction with websites.The scope of the thesis is that four commerce content management systems (CMSs) are compared in this thesis to find out which performs with the lowest page load time. These are Magento, Drupal with commerce, Wordpress with woocommerce and Joomla with Hikashop. The CMSs are all pushed to a very similar website design based on one universal theme, using the twitter bootstrap mobile first responsive framework. The design is based on previousresearch of users mental models for e-commerce websites. A fully functional fictional site Fastcommerce is developed on the four CMSs. The CMSs are filled with one category page of identical sample electronic products (12 items). The products have images and lorem ipsum text. The method of the thesis are experiments. The experiments are conducted to find the page load time on a local environment. The results show clear performance improvements on all four CMSs after applied optimizations. But some of the optimizations cause negative performance consequences.

With increased demand for housing in Sweden's metropolitan regions, it is of greatimportance to meet the need and build more. The supply of housing is governed byaccess to land and what it costs to build apartment houses. In Sweden, there is ahistory of cartel formation of contractors and at the turn of the millennium, thegovernment invested funds to create increased price transparency in theconstruction sector. Based on this, the purpose of this project is to investigate how itis possible to today produce housing more economically, while maintaining quality.The study is limited to the purchase of prefabricated hollow core and load-bearingwall elements in both concrete and wood. The goal is to be able to compare prices ofthese construction parts between Swedish and foreign suppliers. The foreignsuppliers are limited to the ones operating in the Baltic countries and Poland. Thus, itmust be investigated which of the wooden or concrete frames is most economicallyprofitable, what opportunities there are with international purchases of frameelements and what should be taken into account in international purchases. / I och med ökad efterfrågan på bostäder i Sveriges storstadsregioner är det av vikt atti samma takt öka utbudet. Utbudet styrs av tillgång till mark samt vad det kostar attbygga. I Sverige finns en historia av kartellbildning av byggföretag och regeringensatte vid millennieskiftet in medel för att skapa ökad pristransparens inombyggsektorn. Med bakgrund i detta är syftet med examensarbetet att undersöka hurdet idag går att producera bostäder mer ekonomiskt, med bibehållen kvalitet iåtanke. Studien avgränsas till inköp av prefabricerade håldäck och bärandeväggelement i betong respektive trä. Målet är att kunna jämföra priser av dessakonstruktionsdelar mellan svenska och utländska leverantörer. De utländskaleverantörerna avgränsas till att verka inom baltikum och Polen. Således ska detutredas vad utav trä- eller betongstomme som är mest ekonomiskt lönsamt, vilkamöjligheter som finns med internationella inköp av stomelement samt vad som börtas hänsyn till vid internationella inköp.De risker som finns kopplade till just internationella inköp är bland andra risk attprodukten inte stämmer överens med vad som avtalats och leveransförseningar.Logistikrisker begränsas med hjälp av avtal reglerade utifrån det internationellaregelverket Incoterms. Det finns även politiska och valutarelaterade risker medinternationell handel.ISO 9000 är ett kvalitetsledningssystem som ligger till grund för att företag ochorganisationer ska kunna säkerställa att kvaliteten i deras arbete svarar upp motkundens behov och krav. ISO 14000 samlar standarder inom miljöledningssystem.Intervjuer av sex svenska och fem utländska leverantörer om pris och kvalitetsarbetegav intressanta resultat för studien. Samtliga utländska leverantörer är certifierademed ISO 9001 samt ISO 14001. Två av sex svenska bolag har ISO9001-certifieringen och hälften ISO 14001-certifieringen. Att köpa prefabriceradebetongelement är enligt studien inte ekonomiskt lönsammare i utlandet, det är detdäremot att köpa träelement.

Effects of the environmental degradation in the last century rose awareness on the need to manage natural resources in a more sustainable manner. The role of the private sector in greenhouse gases emissions and resources use is significant and hence encompasses huge potential to mitigate the environmental impact of human activities. Environmental Management Systems (EMS) has been regarded as an effective way to manage the environmental impact of enterprises. Factors impacting the performance of EMS in French enterprises are investigated. Three aspects of EMS are studied: managerial processes, policy-making process and tools used to monitor environmental impact. Influence of sectorial activity on EMS is studied. In the first phase, a qualitative research approach is used, and twenty-one French enterprises from different sectors are interviewed. Two types of employees are surveyed: employees in charge of the environmental policy within the enterprise, and employees not related to environmental policies. In the second phase, exploratory factor analysis is employed to identify practices leading to best environmental performance. Results from the exploratory analysis reveal that firms with the highest environmental performance tend to have a long-term agenda and consult external stakeholders, namely their customers, to elaborate their environmental policy. Regarding communication channels to educate employees on sustainable practices, it is found that executives are often more informed on sustainable practices and are not responsive to same channels. Results from the qualitative analysis show lack of financial support is still the first obstacle to EMS implementation, and business strategy is rarely aligned with the environmental strategy of the company. Therefore, there is a strong need to create a compelling business case for EMS. / Effekterna av miljöförstöring under förra seklet ökade medvetenheten om behovet av att hantera resurser på ett mer hållbart sätt. Den privata sektorns roll i utsläpp av växthusgaser och resursanvändning är betydande och omfattar därför en enorm potential för att påverka miljöns hållbarhet. Environmental Management Systems (EMS) har betraktats som ett effektivt sätt att hantera företagens miljöpåverkan. Faktorer som påverkar resultatet av EMS i franska företag undersöks. Tre aspekter av EMS studeras: ledningsprocesser, beslutsfattande och verktyg som används för att övervaka miljöpåverkan. Påverkan av sektoraktivitet på EMS studeras. I den första fasen används en kvalitativ forskningsmetod och 21 franska företag från olika sektorer intervjuas. Två typer av anställda undersöks: anställda som ansvarar för miljöpolitiken inom företaget och anställda som inte är relaterade till miljöpolitiken. I den andra fasen används undersökande faktoranalys för att identifiera metoder som leder till bästa miljöprestanda. Resultat från den undersökande analysen visar att företag med högsta miljöprestanda tenderar att ha en långsiktig agenda och konsultera externa intressenter, nämligen deras kunder, för att utarbeta sin miljöpolicy. Beträffande kommunikationskanaler för att utbilda anställda om hållbar praxis, konstateras att chefer ofta är mer informerade om hållbara metoder och inte svarar på samma kanaler. Resultat från den kvalitativa analysen visar att bristen på ekonomiskt stöd fortfarande är det första hinderet för implementering av EMS, och affärsstrategi är sällan i linje med företagets miljöstrategi. Därför finns det ett starkt behov av att skapa ett övertygande affärsfall för EMS.

Yes / Energy consumption (EC) of consumers primarily depends on comfort level (CL) affirmed by brain sensations of the central nervous system. Environmental parameters such as surroundings, relative humidity, air temperature, solar irradiance, air pressure, and cloud cover directly influence consumer body temperature that in return affect blood dynamics perturbing brain comfort sensations. This CL (either in summer, winter, autumn, or spring season) is a function of external environment and internal body variations that force a consumer toward EC. To develop a new concept of consumer's EC, first the authors described environment parameters in detail with relation to surroundings and EC. Considering this, they tabulated a generic relation of consumer's CL with EC and environment temperature. Second, to build an inter-related bond between the environmental effects on consumer body dynamics, they analysed theoretically and mathematically above mutual relations between medical and environmental sciences. Finally, they present their conceptual EC model based on a closed-loop feedback system. This model is a complex non-linear adaptive system with environmental and surrounding parameters as input to the system resulting in an optimised EC, considering consumer CL as a key parameter for the system.

This research presents a two-part study on a fuel cell electric van (FCEV), focusing on vehicle modelling and developing different control strategies for the modelled vehicle. The modelling phase accounts for the aging effects on the fuel cell (FC) and battery, analyzing FCEV behavior over time. This includes estimating and integrating the degradation impacts on characteristic curves, such as the FC’s polarization and efficiency curves, the battery’s charging and discharging resistance curves, and the open-circuit voltage curve. A simplified fuel cell system (FCS) model is designed to consider power losses in multiple components, including the FC stack, air compressor, and others. The dynamic limits of the FC are also included to yield more realistic results. The model is based on the vehicle Opel Vivaro FC specifications, incorporating parameters like maximum FC power, battery capacity, vehicle weight, and tire dimensions. Subsequently, various control strategies are applied to analyze their effectiveness in FC and battery State-of-Health (SOH) degradation and hydrogen consumption. A rule-based energy management system (EMS) is implemented first, which operates with five different operational modes dependent on the vehicle’s state. This is followed by a look-up table (LUT) based strategy, which uses two two-dimensional tables generated by a Neural Network (NN). The network is trained with discretized optimal / Thesis / Master of Applied Science (MASc)

En el presente estudio se propone el diseño de un sistema de SST para reducir los riesgos laborales en la empresa Casa Blanca SRL. Para ello, se diagnosticó la situación actual de toda la empresa, en el que se identificó un total de 200 días por ausentismo del personal durante el periodo 2019-2021 a causa de accidentes laborales, generando costos directos de S/ 23 275, así como el cumplimiento de solo el 11% en relación a los requisitos de la Ley 29783 y por medio de la matriz Ishikawa se determinó las causales de mano de obra, medio, método y maquinaria. Luego, a través de la Matriz IPER se identificaron un total de 14 riesgos en las actividades de la empresa, de los cuales el 79 % son del tipo moderado y el 21 % son altos. Posteriormente, para el diseño del sistema de SST se terminaron los controles operacionales para las causales antes mencionadas, midiendo el impacto por medio de una matriz IPERC, obteniendo la reducción de riesgos a 86% tolerables y 14% a moderados. Para el diseño de sistema propuesto se tomó en cuenta los documentos y registros obligatorios que establece la ley 29783, proyectándose al cumplimiento de los requisitos en un 86%. Finalmente, con la evaluación económica, se demostró la viabilidad de la propuesta de diseño, obteniendo un VAN de S/ 37 265, TIR de 88% y un B/C de 1,61. / In the present study, the design of an OSH system is proposed to reduce occupational risks in the company Casa Blanca SRL. For this, the current situation of the entire company was diagnosed, in which a total of 200 days due to staff absenteeism during the 2019-2021 period due to work accidents were identified, generating direct costs of S/ 23,275, as well as compliance of only 11% in relation to the requirements of Law 29783 and through the Ishikawa matrix, the causes of labor, means, method and machinery were determined. Then, through the IPER Matrix, a total of 14 risks were identified in the company's activities, of which 79% are of the moderate type and 21% are high. Subsequently, for the design of the SST system, the operational controls for the aforementioned causes were completed, measuring the impact through an IPERC matrix, obtaining a risk reduction of 86% tolerable and 14% moderate. For the proposed system design, the mandatory documents and records established by Law 29783 were taken into account, projecting 86% of the requirements to be met. Finally, with the economic evaluation, the feasibility of the design proposal was demonstrated, obtaining a NPV of S/ 36,436, an IRR of 96% and a B/C of 1.66.

The field of technical consultancy is centered around the value that each individual consultant can provide. This value has its ground in the set of skills and knowledge which the consultant possesses, and from an organizational standpoint, must be probably managed as to be fully utilized within the organization. The knowledge that consultants acquire during project missions is not every fully utilized within the base organization, due to the restrictions of knowledge barriers, prohibiting the transfer and retention of knowledge.    Knowledge management therefore becomes an important aspect to consider in the technical consultancy field, as technology is constantly changing at a higher pace. This are of knowledge management has been neglected in the past, as most research regard knowledge management focus on more linear organization and management consultancy. This report aims to identify what and how knowledge barriers are created within the technical consultancy field and how the barriers affect knowledge acquisitions, transfer, and retention. This report follows a qualitative study approach, with semi structured interviews of 12 managers in key positions at 9 consulting firms, ranging from senior consultancy managers to senior consultants.    The results of the empirical study identified 19 knowledge barriers affecting knowledge acquisition, transfer, and retention. The aspect of knowledge and organizational culture was found to be a foundational part of KM affecting the entire cycle of KM. The major barriers related to technical consultancy holding specialized and diverse knowledge, a lack of adequate knowledge management systems implemented, economic factors affecting KM utilization, market drivers creating barriers and internal as well as external cultural factors affecting the KM cycle.