Global ETD Search

1	Mechanical characterization of strain-hardening cement-based composites under impact loading Heravi, Ali Assadzadeh 01 December 2020 (has links) Strain hardening cement-based composites (SHCC) and textile reinforced concrete (TRC) are two types of novel cementitious materials which can be used for strengthening structural elements against impact loading. Under tensile loading, these composites exhibit a strain hardening behavior, accompanied with formation of multiple cracks. The multiple cracking and strain hardening behavior yield a high strain and energy absorption capacity, thus making SHCC and TRC suitable materials for impact resistant structures or protective layers. The design and optimization of such composites for impact resistant applications require a comprehensive characterization of their behavior under various impact loadings. Specifically, the rate dependent behavior of the composites and their constituents, i.e. matrix, reinforcement, and their bond, need to be described. In the context of dynamic testing, SHCC, TRC and their constituents require customized experimental setups. The geometry of the sample, ductility of the material, the need for adapters and their influence on the measurements, as well as the influence of inertia are the key aspects which should be considered in developing the impact testing setups. The thesis at hand deals with the development process of various impact testing setups for both composite scale and constituent scale. The crucial aspects to be taken into account are discussed extensively. As a result, a gravity driven split-Hopkinson tension bar was developed. The setup was used for performing impact tension experiments on SHCC, TRC and yarn-matrix bond. Moreover, its applicability for performing impact shear experiments was examined. Additionally, a mini split-Hopkinson tension bar for high speed micromechanical experiments was designed and built. In the case of compressive loading, the performance of SHCC was investigated in a split-Hopkinson pressure bar. The obtained results, with focus on tensile experiments, were evaluated concerning their accuracy, and susceptibility to inertia effects. Full-field displacement measurement obtained by digital image correlation (DIC) was used in all impact experiments as a tool for visualizing and explaining the fracture process of the material in conjunction with the standard wave analysis performed in the split-Hopkinson bars.Moreover, the rate dependent behaviors of the composites were clarified with respect to the rate dependent behavior of their constituents. info:eu-repo/classification/ddc/690 ddc:690
2	En bransch i lä? : En komparativ studie om fastighetsbolags innovationsarbete / An industry in the shelter? : A comparative study of real estate companies' innovation work Bergfeldt, Karl, Folkegård, Emma January 2021 (has links) Bakgrund: Fastighetsbranschen klassificeras som en stabil bransch med fastigheter som fortsatt kommer behöva driftas och förvaltas, vilket har lett till få incitament att driva innovation i branschen. Spridningen av innovationer i branschen utgör en brist, även om tillgänglighet av innovationsmöjligheter finns. Medvetenhet om nödvändigheten av innovation inom fastighetsbranschen har dock ökat under de senaste decennierna, vilket har lett till att fastighetsbolagen gjort satsningar på att driva innovation i högre grad. Innovationsarbetet i fastighetsbranschen påverkas av flera externa och interna faktorer. Här råder det en kunskapslucka, då innovationsprocessen i fastighetsbranschen inte är tillräckligt studerat. Syfte och Frågeställningar: Studiens syfte är att med hjälp av en komparativ studie utforska skillnader och likheter i olika fastighetsbolags innovationsarbete. För att besvara detta syfte har följande frågeställningar använts: “Vad är drivkraften till innovation för fastighetsbolagen inom branschen?” samt “Hur ser processen ut för innovationsskapande för aktörer inom fastighetsbranschen och finns det några skillnader samt likheter?” Metod: Denna kvalitativa studie har en abduktiv ansats eftersom studiens teoretiska ramverk har utformats utifrån förintervjuer och en litteraturstudie. Empiriska data har samlats in genom primärdata i form av semistrukturerade intervjuer med fem olika fastighetsbolag vilka sedan har analyserats med en tematisk analysmetod. Slutsats: Vad som driver innovation inom branschen visade sig vara följande områden: omvärldsanalys, hållbarhet, kunder, samarbeten samt intern vilja och drivkraft. Processen för innovationsskapande för de olika bolagen ser olika ut och processerna är individuella för bolagen. Bolagen har flertalet likheter i sina innovationsprocesser med tanke på medarbetarnas involvering, pilotprojekt och hur de mäter om en innovation har uppnått sitt syfte. Olikheter i processerna grundar sig ofta i initiativet till varför bolaget bedriver innovation och hur innovationsprocessen startas. Studien tyder på att de finns olika samarbets-nätverk kopplat till innovation. Samarbetet inom branschen är en viktig komponent i bolagens innovationsprocess och driver innovation i branschen. Ur intervjudatan framkommer det att hinder för branschen framför allt är den stora kapitalintensiteten och att incitament till innovation saknas på grund av den stabila konjunkturen i branschen. / Introduction: The real estate industry classifies as a stable industry with properties that will still need to be operated and managed, which led to few incentives to drive innovation in the industry. The spread of innovations in the industry constitutes a deficiency, even though there is an availability of innovation opportunities. Awareness of the necessity of innovation in the real estate industry has increased in recent decades which has led real estate companies to make efforts in pursuing innovation to a greater degree. The innovation work in the real estate industry is affected by several external and internal factors. There is a knowledge gap here because the innovation process in the real estate industry has not been sufficiently studied. Purpose and research questions: The purpose of the thesis is to explore differences and similarities in the innovation work of different real estate companies through a comparative study. To answer this purpose, the research questions used are: “What are the driving forces for innovation for real estate companies in the industry?” and “What does the process look like for innovation creation for players in the real estate industry and are there any differences and similarities?”. Method: This qualitative study has an abductive approach, which has meant that the study has designed a theoretical frame of reference based on preliminary interviews and a literature review. This qualitative study has an abductive approach. The empirical data has been collected through primary data in the form of semi-structured interviews with five different real estate companies which then have been analysed using a thematic analysis method. Conclusion: What drives innovation in the industry turned out to be the following areas: external analysis, sustainability, customers, collaborations, and internal will and drive. The process of creating innovation for the different companies looks different and the processes are individual for the companies. The companies have several similarities in their innovation processes in terms of employee involvement, pilot projects, and how they measure whether an innovation has achieved its purpose. Differences in the processes are often based on the initiative for why the company conducts innovation and how the innovation process is started. The study indicates that there are various collaborative networks linked to innovation. Collaboration in the industry is an important component in the companies' innovation process and drives innovation in the industry. The interview data shows that obstacles for the industry are primarily the large capital intensity and that incentives for innovation are lacking due to the stable economic situation in the industry. Real estate industry Innovation Innovation work Innovation process Driving forces Innovation systems Product innovation Business process innovation Structural inertia Exploitation Exploration Incremental innovation. Fastighetsbranschen Innovation Innovationsarbete Innovationsprocess Drivkrafter Innovationssystem Produktinnovation Affärsprocessinnovation Strukturell tröghet Exploatering Utforskning Inkrementell innovation Business Administration Företagsekonomi
3	Disruptive Transformations in Health Care: Technological Innovation and the Acute Care General Hospital Lucas, D. Pulane 24 April 2013 (has links) Advances in medical technology have altered the need for certain types of surgery to be performed in traditional inpatient hospital settings. Less invasive surgical procedures allow a growing number of medical treatments to take place on an outpatient basis. Hospitals face growing competition from ambulatory surgery centers (ASCs). The competitive threats posed by ASCs are important, given that inpatient surgery has been the cornerstone of hospital services for over a century. Additional research is needed to understand how surgical volume shifts between and within acute care general hospitals (ACGHs) and ASCs. This study investigates how medical technology within the hospital industry is changing medical services delivery. The main purposes of this study are to (1) test Clayton M. Christensen’s theory of disruptive innovation in health care, and (2) examine the effects of disruptive innovation on appendectomy, cholecystectomy, and bariatric surgery (ACBS) utilization. Disruptive innovation theory contends that advanced technology combined with innovative business models—located outside of traditional product markets or delivery systems—will produce simplified, quality products and services at lower costs with broader accessibility. Consequently, new markets will emerge, and conventional industry leaders will experience a loss of market share to “non-traditional” new entrants into the marketplace. The underlying assumption of this work is that ASCs (innovative business models) have adopted laparoscopy (innovative technology) and their unification has initiated disruptive innovation within the hospital industry. The disruptive effects have spawned shifts in surgical volumes from open to laparoscopic procedures, from inpatient to ambulatory settings, and from hospitals to ASCs. The research hypothesizes that: (1) there will be larger increases in the percentage of laparoscopic ACBS performed than open ACBS procedures; (2) ambulatory ACBS will experience larger percent increases than inpatient ACBS procedures; and (3) ASCs will experience larger percent increases than ACGHs. The study tracks the utilization of open, laparoscopic, inpatient and ambulatory ACBS. The research questions that guide the inquiry are: 1. How has ACBS utilization changed over this time? 2. Do ACGHs and ASCs differ in the utilization of ACBS? 3. How do states differ in the utilization of ACBS? 4. Do study findings support disruptive innovation theory in the hospital industry? The quantitative study employs a panel design using hospital discharge data from 2004 and 2009. The unit of analysis is the facility. The sampling frame is comprised of ACGHs and ASCs in Florida and Wisconsin. The study employs exploratory and confirmatory data analysis. This work finds that disruptive innovation theory is an effective model for assessing the hospital industry. The model provides a useful framework for analyzing the interplay between ACGHs and ASCs. While study findings did not support the stated hypotheses, the impact of government interventions into the competitive marketplace supports the claims of disruptive innovation theory. Regulations that intervened in the hospital industry facilitated interactions between ASCs and ACGHs, reducing the number of ASCs performing ACBS and altering the trajectory of ACBS volume by shifting surgeries from ASCs to ACGHs. Disruptive Disruptive Innovation Theory Disruptive Transformations Disruptive Innovation Innovation Technology Technological Innovation Medical Innovation Medical Technology Medical Advancement Laparoscopy Laparoscopic Surgery open surgery appendectomy cholecystectomy bariatric surgery weight loss surgery appendectomies cholecystectomies inpatient outpatient ambulatory ambulatory surgery ambulatory surgery center acute care general hospital hospital acute care hospital general hospital health care healthcare hospital industry health care industry Clayton Christensen Clayton M Christensen Michael Porter Harvard Business School Virginia Commonwealth University CMS Health policy public policy public administration organizational theory organization theory Population Ecology Theory Competitive Strategy policy analysis John Kimberly Organization Size Structural Inertia liability of smallness health spending health care cost specialty medical facility open system niche width dynamic outpatient department technology shift surgical setting surgical setting shift medical facility shift substitution threat health system system level analysis Ecological Approach hospital trends ambulatory surgery trends reimbursement rate Medicare CMS coverage decision P J DiMaggio DiMaggio and Powell w w Powell Hannan and Freeman M T Hannan Organizational change minimally invasive surgery less invasive surgery Prospective Payment System Outpatient Prospective Payment System entreprenuerial physician health care organization health care management Roice Luke Carl Ameringer new technology surgical utilization elective surgery Medicare Payment Advisory Commission MedPAC coverage decision trends in surgery abdominal surgery surgical variation physician-owned physician ownership physician autonomy outpatient clinic utilization trends unnecessary surgery Pfeffer Salancik technology diffusion redefining health care interdisciplinary research health care delivery panel design diffusion of hospital technology state variation regional variation local health care market government intervention medical facility health care capacity focused factory advances in health care physician organization relationship hospital competition medical specialization hospital expansion medical arms race integrated care integrated health system J E Wennberg health care transformation reimbursement scheme surgical volume Florida Wisconsin policy making health policy analysis competitive dynamics center of excellence intervening factor service line competition service-line competition surgical reimbursement innovative business model innovative technology environmental influence established firm new market entrant patient safety sophisticated technology Harvard Divinity School Social and Behavioral Sciences

1

Page generated in 0.0535 seconds