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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.
41

A manufacturing company's approach to the 2030 UN SDGs affected by institutional differences and theory. : A master thesis within Engineering Management

Bikker, Robin, Chavush, Serkan January 2023 (has links)
Sustainability and sustainable production methods are becoming more important in the manufacturing industry all around the world. Within this trend, United Nations’ formulated 2030 Sustainable Development Goals are used as a target and guideline for developing a roadmap in manufacturing companies’ schedules. For this purpose, there are some existing methods used in practice such as Triple Bottom Line (TBL) management, which is based on the environmental, economic, and social aspects of sustainability. The purpose of this study is aiming to provide insights into the role of the TBL management approach in supporting companies to achieve the UN 2030 sustainability goals. As well as contributing to the ongoing discussions on the importance of sustainable practices in achieving the significance of the study. The findings of this study, gathered through a combination of qualitative primary and secondary data collection, show that there are some similarities and differences between the sustainability practices depending on the SDGs. Approaches of the companies vary with factors such as legislations, culture, and other formal and informal institutions of the country. It is found that most of the Dutch companies act more proactive regarding the SDGs whereas Turkish organisations are more reactive to change. It can be seen that Turkish organisations are very much still primarily focused on the economical perspective of TBL. Dutch organisations tend to prioritise the social and the environmental aspects more than their Turkish counterparts. It can also be identified that Turkish organisations tend to be incredibly focused on legislations, whereas Dutch organisations are more often moving towards their own visions and how they want to position themselves in the market. Even though there is a significant difference between the Dutch and Turkish organisations, it can be identified that the economical aspect plays a major role in both cases. Yet the way they work towards this differs strongly.
42

Exploring the influence of size and geography on SMEs’ and large corporations’ CSR practices in Hungary and in Sweden when facing financial shortage

Gaál, Bence, Vágó, Georgina January 2022 (has links)
Background: CSR has become an integral part of most businesses during the years, however, it has not necessarily happened by choice for every company. Stakeholders have become aware of the negative impact ofcorporations’ operations and actions on the planet and on society, consequently, they started to pressure companies to be more responsible when conducting business. However, facing financial shortages might interfere with the accomplishment of these practices and corresponding activities. Furthermore, as differently sized and differently located companies might practice CSR in a different way, size and geographical location might also have an influence on these CSR practices and activities. Purpose: The purpose of this research is to explore the influence of size and geography on CSR practices and activities adopted by SMEs and large corporations in Sweden and in Hungary when facing shortage in their financial resources. Method: In order to achieve the purpose, a qualitative research method has been used. Multiple case studies were conducted with two Hungarian SMEs, a Hungarian large enterprise, a Swedish SME and a Swedish large firm. The empirical data was collected with the help of semi-structured interviews as well as data from corporate websites, annual reports, sustainability reports and social media. Conclusion: The results of this thesis show that the approach each company takes to practicing CSR seems to influence all of their activities. The size of the company appears to influence fewer practices, while geography comes across as having the least influence among these factors.
43

Hållbarhetsrapporten: Tillräcklig eller bristfällig? : En kvalitativ studie om hållbarhetsrapportens tillräcklighet

Karlsson, Julia, Johnsson, Moa January 2023 (has links)
Thinking sustainably is becoming increasingly important among companies. Today, there are demands from both stakeholders and the law to conduct sustainable operations. Companies have a social and ethical responsibility to achieve competitive advantage and a good corporate reputation. This is one reason why more and more companies today establish sustainability reports for their operations. It can be questioned whether the sustainability report is sufficient or if it is deficient. This study describes and explains the content of the sustainability report by analyzing the adequacy of the report and how it may develop in the near future. The essay is based on interviews with eleven respondents who are divided into four professional groups, accountants, companies, investors and academics. These professional groups have contributed an external and internal perspective to the sustainability report, which has provided a deeper understanding of the subject. The essay is based on a qualitative method with a deductive approach. There, the data material has been analyzed with the help of the theory section in order to be able to answer the essay's purpose and questions. The conclusion of the study is that the sustainability report is deficient, which is due to a lack of framework and regulation. The new regulation and framework of the future is well needed, but there is a clear doubt about the implementation.
44

New trends in environmental and socially responsible management in the cement manufacturing

Verma, Mangleshwar N. January 2011 (has links)
This thesis explores the environmental and social responsibilities being increasingly shouldered by cement manufacturing sector and outlines a new approach for these companies to accept their responsibilities and to utilise professional approaches to address the economic, environmental and social dimensions of sustainable business. Managing these three dimensions in business translates corporate responsibility into an integrated responsibility for doing business profitably, ethically and in sustainable manner. This three-pronged approach is sometimes called the Triple Bottom Line. It helps companies to fulfil their more holistic Corporate Social Responsibility. A critical review of the literature led the thesis author to develop the theoretical framework for environmental and social reporting to proceed on TBL/CSR journey within the cement industry. Data were collected from TBL/CSR reports from cement companies on key environmental and social performances. Based upon those data, a questionnaire was developed to obtain more information from the leading worldwide cement companies. The combined results of the responses to the questionnaire and the quantitative data derived from the TBL/CSR reports were used to establish best practice benchmarks to serve as performance targets for the author's case study company, Oman Cement Company (OCC). The contribution to knowledge of this research is the summarisation and prioritisation of the cement industry's implementation of TBL/CSR management systems, which integrate the elements of TBL/CSR into their strategic plans and daily operational procedures. Guidelines were derived from the Global Reporting Initiative, the United Nations Global Compact and the new ISO 26000 standard, which promotes a new way of working towards innovation, value creation and incremental actions for transforming businesses to become more responsible. The contributions to practice of this research are the practical and procedural insights, gained by quantitative analysis of environmental and social indicators, into how cement companies are making improvements in their processes and products in response to climate change, economic, governmental regulations and social pressures for improvement. Based upon the findings, recommendations and timetables were developed and are being implemented within the OCC as it progresses on its TBL/CSR journey.
45

Moral (de)coupling : moral disengagement and supply chain management

Eriksson, David January 2014 (has links)
This research aims to fill an important gap in focusing on why individuals are able to take part in and/or support activities that have effects on economic, environmental, and social dimensions that are not consistent with their sense of right and wrong. The research focuses on the relationship between supply chain management and moral disengagement, and how this relation affects social responsibility. After observing individuals avoiding responsibility for misconduct an explanatory concept, moral decoupling, was proposed. Moral decoupling considers moral responsibility a flow in the supply chain. Moral decoupling occurs when the flow is restricted. If moral decoupling occurs at an identifiable point it is called a moral decoupling point. The concept was developed by identifying and linking specific supply chain activities and structures with moral disengagement, a theory that explains the deactivation of self regulation. Moral decoupling was able to suggest how to reduce moral disengagement and improve social responsibility. To validate the suggestions a literature review on social responsibility was conducted and identified sixteen elements of social responsibility in supply chain management. The suggestions based on moral disengagement were compared with elements of social responsibility and a large overlap was found. Lastly, suggestions on how to reduce moral disengagement and map moral responsibility in a supply network are proposed, links between elements of social responsibility are presented, and moral coupling is added as a complementary term to moral decoupling. A model explaining the relationship between ethical guidelines, moral responsibility, moral decoupling, and social responsibility is proposed. In relation to current theoretical knowledge the thesis has contributed to the field of socially responsible supply chain management with an application of a new theoretical lens that gives one explanation as to why identifed elements of social responsibility are important. The understanding of social responsibility has reached an increased explanatory depth following the identification of moral disengagement as a generative mechanism, subject to conditions in supply chain management. The research has also applied moral disengagement in a context not identified in earlier research, and shows some of the complexity of applying it to a real-world global context. The elements of social responsibility and moral (de)coupling help practitioners identify what they should focus on to increase social responsibility and also offer an explanation for `why?'. The findings can be used to construct supply chains that are less prone to misconduct and to identify where in the chain it is important to be aware of immoral behavior. The value and originality of this research is centered on the application of a new theoretical lens for socially responsible supply chain management. It is the only identified research in the area which identifies mechanisms on a generative level that explains human behavior and conditions to which those mechanisms are subject. This is also in itself a novel application of moral disengagement in a new research context. / <p>Doctoral thesis for the degree of Doctor of Philosophy in Textile Management at the University of Borås to be publicly defended on Wednesday, December 10, 2014, at 1:00 p.m.,in room M404, University of Bor as, Allégatan 1, Borås</p>
46

Supplier Development for TBL Outcomes: a survey on Brazilian based organizations / Desenvolvimento de fornecedores sustentáveis: uma pesquisa survey com organizações brasileiras

Pedroso, Carolina Belotti 03 April 2019 (has links)
Supply chains are increasingly incorporating sustainable elements as mean to meet intensified TBL awareness in the market and to promote competitiveness. Suppliers play a key role in enhancing Triple Bottom Line (TBL) outcomes in supply chain since they are responsible for raw materials that will be incorporated in the final product. Supplier Development (SD) can improve suppliers\' TBL capabilities, improving TBL outcomes throughout the supply chain. This research aims to explore Triple Bottom Line Supplier Development (TBL SD) for an improved TBL performance at supply chain level. To address the research general purpose a systematic literature review was conducted, followed by a basic literature review, in order to identify TBL SD practices, enablers and barriers. The systematic literature analysis was performed with support of QDA Miner software. A survey was performed involving Brazilian buying organizations to investigate the impact of TBL Supplier Development on the organizations\' performance at the operational, environmental and social dimensions. Data were analyzed using Partial Least Square Structural Equation Modeling (PLS SEM) through Smart PLS 3 software. The results obtained point that practices adopted by organizations are in accordance to what literature suggests, highlighting the role of training and resources sharing as important practices adopted. The most impactful enablers to enable TBL SD are supplier evaluation, resources availability, and TBL culture at organizational level. Surprisingly, barriers appeared to be only slightly negatively correlated to TBL SD Adoption. It can be concluded that TBL SD adoption leads to improvements in all TBL legs (Operational, Environmental, and Social) although the impact on environmental performance is stronger. In turn, it was found that enhanced environmental performance can lead to improvements in both social and operational performance. Another interesting finding is that organizations in the Brazilian context are adopting TBL SD for internal reasons, and not due to pressures coming from the local market and community. / As cadeias de suprimentos estão incorporando cada vez mais elementos sustentáveis como meio de atender à crescente conscientização do mercado e promover competitividade. Fornecedores desempenham um papel fundamental no aprimoramento dos resultados sustentáveis na cadeia de fornecimento, uma vez que são responsáveis pelas matérias-primas que serão incorporadas no produto final. Nesse contexto, o desenvolvimento de fornecedores pode melhorar as capabilidades sustentáveis dos fornecedores, entregando melhores resultados a toda a cadeia de suprimentos. Esta pesquisa tem como objetivo explorar o Desenvolvimento de Fornecedores Sustentáveis para um melhor desempenho sustentável no nível da cadeia de suprimentos. Para atingir o objetivo geral da pesquisa, foi realizada uma revisão sistemática de literatura, seguida de uma revisão básica da literatura, a fim de identificar as práticas de desenvolvimento sustentáveis, fatores influenciadores e barreiras. A análise da revisão sistemática da literatura foi realizada com o apoio do software QDA Miner. Uma survey envolvendo organizações brasileiras foi realizada para investigar o impacto da adoção do Desenvolvimento de Fornecedores Sustentáveis no desempenho das organizações pesquisadas, tanto nos aspectos operacionais, ambientais e sociais. Os dados foram analisados usando a Modelagem de Equações Estruturais por Mínimos Quadrados Parciais através do software Smart PLS 3. Os resultados obtidos apontam que as práticas adotadas pelas organizações estão de acordo com o que sugere a literatura, destacando o papel do treinamento e compartilhamento de recursos como práticas importantes adotadas. Os fatores influenciadores mais impactantes para a adoção do Desenvolvimento de Fornecedores Sustentáveis são avaliação de fornecedores, a disponibilidade de recursos e a cultura sustentável no nível organizacional. Surpreendentemente, as barreiras parecem estar ligeiramente correlacionadas de forma negativa com adoção do Desenvolvimento de Fornecedores Sustentáveis. Pode-se concluir que a adoção do Desenvolvimento de Fornecedores Sustentáveis leva a melhorias em todas as dimensões da Sustentabilidade (Operacional, Ambiental e Social), embora o impacto no desempenho ambiental seja mais forte. Por sua vez, o desempenho ambiental pode levar a melhorias no desempenho social e operacional. Outra constatação interessante é que as organizações no contexto brasileiro estão adotando o Desenvolvimento de Fornecedores Sustentáveis por motivos internos, e não devido a pressões vindas do mercado e da comunidade local.
47

Sustainable drivers and performance in Corporate Social Responsibility

De Jong, Stefan, Svensson, Peter January 2014 (has links)
Purpose To determine sustainable Resource Based View drivers (RBV) (i.e. resources, capabilities) and motivation for the successful (i.e. positive Financial (FP) / Social Performance (SP)) implementation of Corporate Social Responsibility (CSR) in the strategies of top performing companies in regards to CSR. In addition to find out how these drivers are being nourished, developed and utilized in order to contribute to the sustainable development in companies. Design/ Methodology/ Approach Interviews are held with CSR-managers from top performing companies based on their engagement and performance in CSR. In addition, their Corporate Responsibility (CR) reports are observed in order to apply triangulation on the company’s engagement in CSR. Furthermore shall reports by third party organizations be observed to get multiple perspectives on the concept of CSR and Sustainability? Lastly an exclusive guest lecture at Linnaeus University is attended which provided insight on corporate partnership in regards to CSR from the point of view of a charitable organization. Findings The most important non-financial drivers of CSR and Sustainability are; knowledge flow, capabilities and competence. Knowledge can be acquired through active engagement with all the company’s stakeholders, especially by collaborating with universities and for example charitable organizations. Companies have invested in the training of top level management in their understanding of the importance of CSR and Sustainability. This is because the top level management is seen as the driving and deciding force within the company to engage in CSR and Sustainability. Some companies have invested research in the understanding of their stakeholders’ perceptions on Sustainability issues which they deem as most important. Delimitations/ Limitations This research investigates the non-financial drivers (i.e. sources and antecedents) of CSR and Suitability in order to invest in and develop the drivers with the purpose of further developing Sustainability. This research is primarily focussed on Swedish companies as they seem to be further advanced in this subject due to for example legislation and the fact that Sweden is one of the most prosperous countries in the world. The purpose of this research is not to generalize the findings, but to provide insight so other companies could learn and develop themselves further in their pursuit for Sustainability.  Implications In order to develop Sustainability further companies need to create tighter collaborations with especially universities as the managers and business leaders for the future, but also other employees, are the students of today. Especially business students complain about the way their subject is being taught as it fails to thoroughly address current and future business problems. Furthermore the concept of Sustainability should be taught not only at universities but at high schools as well, because the society as a whole needs to collaborate to deal with the mega forces that await us in the not too distant future.  Originality/ Value CSR finds itself in a cross-section in academic literature between different affecting disciplines. By combining the different disciplines the authors want to contribute to sustainable development and competitive advantage in CSR-strategies by examining top performing companies who are (perceived to be) well advanced in this subject. Previous research has primarily focussed on proving the relationship between implementing CSR and positive Financial Performance (FP) as the driver of CSR. Much less have other antecedents to CSR been investigated with purpose of further improving sustainable development.
48

Lite snack och mycket verkstad : En studie om vilka verktyg som kan hjälpa restauranger att bli mer hållbara

Dahrén, Adam, Streijffert, Märta January 2018 (has links)
Klimatkrisen är en svår utmaning som alla på planeten tillsammans måste försöka att lösa. En av de branscher som idag har en stor negativ påverkan på klimatet är restaurangbranschen där verksamheterna främst arbetar med livsmedel, vilket har påvisats bidra till en stor mängd växthusgasutsläpp. Restaurangbranschens verksamheter behöver därmed ställa om till att bli mer hållbara när det kommer till såväl ekonomisk som social och ekologisk hållbarhet. Det finns en efterfrågan från restauranger som vill ha hjälp med att ställa om sina verksamheter till att bli mer hållbara, då de har svårt att veta vart och hur de påbörjar detta arbete. En genomlysning av aktuell forskning har visat på att det finns ett behov av att ta fram konkreta verktyg som underlättar hållbarhetsarbetet för verksamheter.Denna studie har därför haft som avsikt att besvara problemformuleringen:Vilka verktyg är praktiskt tillämpbara för att uppnå en hållbar restaurangverksamhet?Vi författare till denna studie valde att genomföra en explorativ studie då detta ansågs ge bättre möjligheter till att skapa en djupare förståelse inom vårt valda problemområde. För att ta reda på vilka verktyg som kan anses vara lämpliga för restaurangverksamheter har teorier, kopplat till förutsättningar och hinder, presenterats för att skapa en förståelse för vad som kan påverka valet av lämpliga hållbarhetshanteringsverktyg. De verktyg som har valts ut till denna studie är: hållbarhetsredovisningar, livscykelanalys, kvalitetsledningssystem, nätverk, utbildning samt grön nudging.Semi-strukturerade intervjuer genomfördes där respondenternas svar tyder på att det finns förutsättningar inom restaurangbranschen för att arbeta med hållbarhet. Intervjuerna visade även på att det finns hinder för detta, främst i form av tid, pengar och snäv kunskap om hållbarhet. Som komplement till intervjuerna framtogs en enkät för att undersöka respondenternas attityd till de utvalda verktygen. Det som anses vara det bäst lämpade verktyget för restauranger att implementera är utbildning, då kunskap är grundläggande för ett framgångsrikt hållbarhetsarbete. Även verktygen nätverk och grön nudging har visat sig vara väl lämpade för restaurangverksamheter.Studien har även bidragit med framtagandet av en modell, vars syfte är att bidra med struktur till studien, som visar de olika steg som restauranger bör genomgå innan implementering av ett verktyg på den operativa nivån av verksamheten. Vidare visas även vilka förutsättningar som är väsentliga och vilka hinder som kan uppstå, för att kunna arbeta med hållbarhet i verksamheten. De verktyg som anses vara mest praktiskt tillämpbara för restauranger är också de verktyg som har bäst förutsättningar och minst hinder för att kunna implementeras i verksamheternas dagliga drift.
49

Joining Forces: A Study of Multinational Corporations' Sustainability Contributions to a Cross-Sector Social Partnership

Backman, Malin, Jangsell, Klas, Lönnqvist, Josephine January 2017 (has links)
Background: Cross-sector social partnership (CSSP) is a joint effort that utilizes resources from different sectors to solve social issues, such as poverty, pandemics and environmental degradation. According to the United Nations, the environmental tipping point of global warming is soon reached, and to avoid this irreversible situation, the collaboration between state and non-state actors is a requirement. With extended resources gained from different sectors, the outcome of the CSSP is greater than if the actors were handling issues by themselves. Problem: There is a growing trend of CSSPs that strive to mitigate climate change, and the Climate Council of Jönköping is a practical example of this phenomenon. Multinational corporations (MNCs) have a large environmental impact and therefore they have a special responsibility to contribute to communities’ efforts to tackle climate change. Furthermore, within CSSP literature, additional research of corporations’ roles in CSSPs has been suggested. Purpose: Considering the increased focus on partnership practices, along with research gaps and complex CSSP elements, the purpose of this thesis is to investigate how MNCs contribute to the CSSP, the Climate Council of Jönköping. Method: Descriptive research was used to describe how MNCs contribute to a CSSP. With an abductive approach, deeper knowledge about the Climate Council of Jönköping as a phenomenon was gained. Empirical data was collected through a qualitative study, consisting of observational research and in-depth interviews, which was analyzed by making use of template analysis. The MNCs of the Climate Council of Jönköping are Castellum, GARO, Husqvarna Group, IKEA, and Skanska. Conclusion: The major conclusion of this study is that the MNCs perceive that their task within the Climate Council of Jönköping is to be a role model and to exchange ideas and knowledge regarding sustainability with other actors. Within CSSP literature, trust among actors, clearly-defined roles, and bridging each other’s weaknesses, are central concepts. The findings about the MNCs deviate from this, as all these factors are not identified. This suggests that the Climate Council of Jönköping and the MNCs do not contribute to public value and mitigating climate change as much as they possibly could.
50

Beam position monitoring in the clic drive beam decelerator using stripline technology

Benot Morell, Alfonso 16 May 2016 (has links)
[EN] The Compact Linear Collider (CLIC) is an electron-positron collider conceived for the study of High-Energy Physics in the TeV center of mass energy region, is based on a two-beam operation principle: instead of using active elements (klystrons), the necessary RF power to accelerate the Main Beam (MB) is obtained from the deceleration of a high-current, moderate energy Drive Beam (DB) in the so-called Power Extraction and Transfer Structures (PETS). These structures emit an RF signal of about 130 MW power at 12 GHz. As this frequency is above the cut-o ff frequency of the fundamental mode for the specified beam pipe dimensions (7.6 GHz), the inference propagates from the PETS to the neighboring devices, including the Beam Position Monitors (BPM). According to the CLIC Conceptual Design Report (CDR), an ef ficient beam position monitoring system for the CLIC DB decelerator needs to meet the following requirements: - It should be as simple and economic as possible, as 41580 units are required, amounting to 75% of all CLIC BPMs. - The signal processing scheme should not be a ffected by the PETS interference. This rules out processing the signals at the beam bunching frequency (12 GHz). - The resulting position signal should detect changes in the beam position whose duration is 10 ns or longer. - The required spatial resolution is 2 um for a 23 mm diameter vacuum pipe. - Wide dynamic range: the electronic acquisition system must be able to process signals with extreme levels, induced by either very high (100 A) or very low (3 A) current beams. This PhD thesis describes the electromagnetic and mechanical design of the first prototype BPM developed for the CLIC Drive Beam and its characterization tests in laboratory and with beam. The first two chapters introduce the CLIC project and review the state-of-the-art beam position monitoring techniques. Chapter 3 presents the design of the BPM. The stripline technology has been selected, as it is the only one among the most commonly used BPM techniques to present a suitable frequency response to filter out the RF interference caused by the PETS. Choosing an appropriate length for the electrodes, it is possible to tune one the periodic notches in the stripline frequency response to 12 GHz. The influence of di erent electromagnetic and geometrical aspects is also studied, such as beam coupling impedance or the ratio between longitudinal and transverse dimensions. The design of the electronic acquisition system is presented in Chapter 4, considering the project requirements in terms of resolution (2 u m), accuracy (20 um) and time resolution (10 ns). Due to the high amount of units required, the number of electronics components has been minimized. As the designed signal processing scheme is based on charge integration, it can be adapted to di erent stripline pick-ups by simply modifying the attenuator settings according to the required output signal levels. The laboratory characterization tests of the prototype stripline BPM, in the low and the high frequency ranges, performed with a thin wire and a coaxial waveguide, respectively, are described in Chapter 5. The measurement results are compared with the theoretical estimation and the electromagnetic field simulations. In addition, the high-frequency test reveals that the first prototype stripline BPM does not provide su cient suppression of the 12 GHz PETS RF interference. An additional study proposed several modifications and guidelines for a second prototype stripline BPM. Finally, Chapter 6 presents the beam tests of the prototype stripline BPM at the CLIC Test Facility 3 (CTF3) in the Test Beam Line (TBL), a scaled version of the CLIC Drive Beam decelerator. Two types of tests were performed: linearity/sensivity and resolution. These results are compared to the ones in the laboratory characterization tests. An upper bound of the resolution is estimated performing a Singular Value Decomposition (SVD) analysis. / [ES] El Colisionador Lineal Compacto (Compact Linear Collider, CLIC), un colisionador de electrones y positrones concebido en el CERN para el estudio de la Física de Altas Energías en la región de los TeV, se basa en un principio de funcionamiento de doble haz: en lugar de emplear elementos activos (klystrons) para proporcionar la potencia RF requerida para acelerar el haz principal (Main Beam, MB), ésta se obtiene de la deceleración de un haz secundario (Drive Beam, DB), de alta corriente y energía moderada, en las llamadas estructuras de extracción y transferencia de potencia (Power Extraction and Transfer Structures, PETS). Estas estructuras emiten una señal interferente RF de más de 130 MW de potencia a 12 GHz, que, por estar localizada en una frecuencia superior a la de corte del modo fundamental en el tubo de vacío del haz (7.6 GHz), se propaga por éste hacia los dispositivos adyacentes, entre los cuales se encuentran los sistemas de monitorización de la posición (Beam Position Monitor, BPM). De acuerdo con el informe conceptual de diseño de CLIC (Conceptual Design Report, CDR) , un sistema eficiente de monitorización de la posición del haz en el decelerador del haz secundario deberá cumplir los siguientes requisitos: - Debe ser lo más sencillo y económico posible, ya que se precisan 41580 unidades: el 75% de todos los BPMs de CLIC. - El procesado de señal en el sistema de adquisición deberá ser inmune a la interferencia generada en las PETS. Esto excluye la solución habitual de procesar las señales del BPM a la frecuencia de pulsado del haz (12 GHz). - La señal de posición resultante del procesado debe ser capaz de detectar cambios en la posición del haz de duración igual o mayor a 10 ns (resolución temporal). - La resolución espacial requerida es de 2 um para un tubo de vacío de 23 mm de diámetro, con una calibración precisa. - Amplio rango dinámico: el sistema electrónico de adquisición del BPM debe poder resistir los altos valores de señal provocados por los casos de desviación extrema del haz nominal (se contempla una desviación máxima de la mitad del radio del tubo), así como detectar las señales inducidas por las configuraciones de haz con menor carga de todas las previstas, cuyos niveles serán muy débiles. / [CAT] El Col·lisionador Lineal Compacte (Compact Linear Collider, CLIC), un col·lisionador d'electrons i positrons concebut per l'estudi de la Física d'Altes Energies a la regió dels TeV (energía del centre de massa), es basa en un principi de funcionament de doble feix:en lloc de fer servir elements actius (klystrons) per proporcionar la potència RF requerida per accelerar el feix principal (Main Beam, MB), aquesta s'obtè de la desacceleració d'un feix secundari (Drive Beam, DB), d'alt corrent i energia moderada, a les anomenades estructures d'extracció i transferència de potència (Power Extraction and Transfer Structures, PETS). Aquestes estructures emeten una senyal interferent RF de més de 130 MW de potència a 12 GHz, que, pel fet d'estar localitzada a una freqüència superior a la de tall del mode fonamental al tub de buit del feix (7.6 GHz), es propaga a través d'aquest fins els dispositius adjacents, entre els quals trobem els sistemes de monitorització de la posició (Beam Position Monitor, BPM). D'acord amb l'informe conceptual de disseny de CLIC (Conceptual Design Report, CDR), un sistema eficient de monitorització de la posició del feix al desaccelerador del feix secundari haurà de complir els següents requisits: ¿ - Ha de ser el més senzill i econòmic possible, ja que es necessiten 41580 unitats: el 75% de tots els BPMs de CLIC. ¿ - El processat de la senyal al sistema d'adquisició haurà de ser inmune a la interferència generada als PETS. Això exclou la solució habitual de processar les senyals del BPM a la freqüència de pulsacions del feix (12 GHz). ¿- La senyal de posició resultant del processat ha de ser capaç de detectar canvis a la posició del feix de durada igual o més gran que 10 ns (resolució temporal). ¿- La resolució espaial necessària és de 2 um per a un tub de buit de 23 mm de diàmetre. ¿- Ampli rang dinàmic: el sistema electrònic d'adquisició del BPM ha de poder processar senyals amb nivells extrems, induïdes per feixos de molt alt (100 A) i molt baix (3 A) corrent. / Benot Morell, A. (2016). Beam position monitoring in the clic drive beam decelerator using stripline technology [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64067 / TESIS

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