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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.
181

Disruptive innovation theory in the paper- and packaging industry : Applying Clayton Christensen in a new context

Strömberg, Joakim, Thorman, Philip January 2019 (has links)
The paper- and packaging industry has for a long time transitioned from a production-focused industry towards a customer-orientation – today the customers have become fundamental. Managers are searching for ways to create superior innovations in the industry which can compete against the oil-based solution, i.e. plastic. However, they face challenges as they attempt to launch products in the market. One exciting scholar who has researched much about the challenges of incumbent firms is Clayton Christensen and his theory of disruptive innovation. The theory has received much attention throughout the years and provides with a holistic literature framework to analyze the industry. The thesis aims to investigate Clayton Christensen’s disruptive innovation theory in order to problematize it in a new context, the paper- and packaging industry. This will be done by discussing how individuals argue, understand and use the term ‘disruptive innovation’ and also discuss Christensen’s Innovator’s Dilemma in relation to how incumbents tend to manage their innovation projects in the industry. The research used a qualitative research approach implementing one case study. Interviews with incumbent actors in the industry, one producer and two brand-owners, pertaining to an innovation project constituted for the empirical findings. The data analyzed through a theoretical lens of Christensen’s disruptive innovation theory. From an iterative process between theory and empirical findings the thesis has made the following contributions. First, we have problematized Christensen in a new context and identified an industry which is considered an anomaly in Christensen’s theory. The industry is unlikely to be subjected to the Innovator’s Dilemma due to its fundamentals as an industry, e.g. collaborations between actors and listening to customers. Second, our practical contribution is the importance of differentiating between sustaining and disruptive innovation, especially concerning radical and disruptive innovation. If an individual does not have a theoretical understanding of disruptive, it is common to be confused concerning the differences between radical and disruptive innovation. However, learning about the differences creates an opportunity to identify new ways of gaining value.
182

Identifying Sources of Disruption in the Context of Sustainability-Driven Innovation

Ottosson, Fredrik, Sevandersson, Rickard January 2019 (has links)
Introduction: Research shows that the lifespan of large companies gets shorter and shorter, the average age of companies on the list of fortune 500 is 33 years, the average age is expected to decline to 12 years by 2027 (Anthony et al., 2018). Innovations that are driven by social, environmental or sustainability issues are defined as sustainability-driven innovations (Metz, 2016). Not much is known when it comes to what sources can trigger a disruptive sustainability-driven innovation.    Problem background: There has been many troubling studies about the damage we as humans bring upon our blue planet, these studies are apocalyptic (Osborn 1948; Carson 1962; Meadows et al 1972; Cole et al 1973). To be able to meet the aspirations of millions rising from poverty, we need transformation and change throughout society, and disruptive innovations is the key to unlock this transformation (Sterman, 2015). The disruption literature is well developed when it comes to what sources can trigger a disruptive innovation. There does not exist literature on what sources that can trigger sustainability-driven innovations.   Purpose: The purpose of this thesis is to create a conceptual model that show possible sources of disruption for sustainability-driven innovations. The knowledge created by the conceptual model will be used at a later stage to develop a monitoring tool for TOMRA. To fulfill the purpose of this master thesis we have developed the following research question: what sources can trigger a disruptive sustainability-driven innovation?   Methodology: To answer the research question, this thesis used an exploratory research design, inductive research approach and the single case study with participants from four companies that acts in three different industries and five interviews with experts in the field of sustainability-driven innovations as the chosen research method. The primary data has been collected from 13 interviews from new entrants, incumbents, experts and governmental agencies. Secondary data were collected to support the analysis.   Findings: The key findings of this thesis are eight new sources of disruption; established technology, public value, public opinion, political decisions, political goals, legislations, subsidizations and demo-pilots    Conclusion: Our study showed that there was a gap in the disruption literature, especially when it comes to the source of disruption. Because the study found other sources that might trigger a disruption rather than only new technology and new BMs. Realizing that, the sources of disruption were expanded to have three subcategories that influence each other, technology and BM, citizen awareness and policy.
183

An investigation of two different modalities of language used in an educational setting and the behaviour of deaf learners.

Swanepoel, Brandon 06 September 2012 (has links)
Research conducted on the prevalence of behavioural adjustment in Deaf children and adolescents, in erstwhile countries, points towards an appreciably elevated percentage of emotional and behavioural problems amongst this population group when compared to hearing normative groups. Studies specify that the prevalence of behaviour and emotional problems in Deaf children and adolescents varies from 4.8% to 50.3%. From existing research conducted, it is ambiguous as to why the reported prevalence rates of maladjustment are higher amongst Deaf children and adolescents. This pioneering study is the first of its kind to research dissimilar modalities of language used as the language of learning and teaching (LoLT) in schools for Deaf learners and how this could possibly correlate to learner behaviour in the classroom. Taking into consideration the reported pervasiveness of maladjustment in Deaf children and adolescents; this study uses the Teacher Report Form (TRF) to investigate the types of behaviour problems displayed by Deaf learners in the classroom. It further investigates whether Deaf learners display certain types of behaviour problems when dissimilar modalities of language are used as the language of learning and teaching. The overall findings of this study suggest that teachers who use manually coded spoken language report an elevated prevalence of behaviour problems on the TRF compared to teachers who use South African Sign Language (SASL). Results further suggest that the group of teachers who use SASL report somatic complaints and attention problems as the most frequently encountered behaviour problems in their classrooms. In comparison the group of teachers who use manually coded spoken English (MCE) report social problems and attention problems as the most frequently encountered behaviour problems in their classrooms. Limitations of this study and suggestions for future research are discussed.
184

Comportamentos de indisciplina: um estudo com a 4a. série do ensino fundamental / Misbehavior in classroom: a study with the 4th grade of basic education

Yasumaru, Vital Toshio 06 June 2006 (has links)
Made available in DSpace on 2016-04-28T20:57:01Z (GMT). No. of bitstreams: 1 Dissertacao VITAL TOSHIO YASUMARU.pdf: 473360 bytes, checksum: 83064cf39ed00040ea184374eeef6507 (MD5) Previous issue date: 2006-06-06 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / As regards to the problems faced by the teachers, misbehavior in classroom is today one of the most boarded subjects. Although it is considerable the amount of works of reflection on the subject, is scarce the number of empirical research that aims to study this phenomenon as it occurs in the classroom. This research, which has as main purpose the understanding of the occurrence of misbehaviors in classroom, aims to comprehend why they occur, identifying the more recurrent ones, the antecedent situations and how teachers act ahead of these behaviors. We work with teachers and students of five classes at Basic Education of two public schools at São Paulo. In the data collection, we made use of the observation in classroom, with cursive register of the occurrence. Our analysis of data is based on the Functional Analysis of the teachers and students interaction. Therefore, the relations between the behaviors of indiscipline with its antecedents and consequences were identified. It was verified that student s most recurrent behavior, in all the groups, was talking and walking in classroom. The occurrence of violent or aggressive behaviors is practically inexistent. Also was verified that teachers propose small quantity of lessons in a long period of time, lessons which showed up repetitive (copy-exercise-correction at the blackboard) and that didn t demand students active involvement. Such situations promote the misbehavior occurrence. It was noticed that two of the teachers excessively demand the silence of the students in classroom, while the other three had revealed more permissive. All of them, however, had presented a coercitive intervention model, what is not effective at misbehavior decrease or elimination. The occurrence of misbehaviors is related to the didactic-pedagogical performance of the teachers. If the teachers do not demand suitable activities in order to keep the students engaged in academic activities to the available time, misbehaviors occur. Nevertheless, the teachers need act in function of the student learning instead of being acting constantly in function of discipline maintenance in classroom / A indisciplina em sala de aula é hoje um dos principais temas abordados no que diz respeito aos problemas enfrentados pelos professores, sejam eles do Ensino Médio ou do Ensino Fundamental. Apesar de ser considerável a quantidade de trabalhos de reflexão sobre o tema, é escasso o número de pesquisas empíricas que buscam estudar este fenômeno tal como ocorre na sala de aula. Este trabalho, que tem por objeto de estudo os comportamentos de indisciplina em sala de aula, visa compreender porque ocorrem, identificando os mais recorrentes, as situações que lhe são antecedentes e as formas de atuação do professor diante de sua ocorrência. Os sujeitos desta pesquisa foram professores e alunos de cinco turmas da 4ª série do Ensino Fundamental de duas escolas estaduais de São Paulo. Foi utilizada, na coleta dos dados, a observação em sala de aula, com registro cursivo do ocorrido. Nossa proposta de análise do ocorrido baseia-se na Análise Funcional da interação entre professores e alunos. Para tanto, identificam-se as relações entre os comportamentos de indisciplina com seus antecedentes e conseqüentes. Como resultados verificou-se que os comportamentos mais recorrentes dos alunos, em todas as turmas, foram conversar e andar em sala de aula. É praticamente inexistente a ocorrência de comportamentos violentos ou agressivos. Verificou-se que os professores propõem poucas atividades para o tempo disponível, atividades que apresentam um padrão repetitivo (cópia-exercício individual-correção na lousa) e que não exigem a participação ativa do aluno, situações estas favorecedoras da ocorrência de comportamentos de indisciplina. Quanto à forma como os professores atuam, notou-se que dois professores exigem excessivamente o silêncio dos alunos em sala de aula, sendo que os outros três mostraram-se mais permissivos. Todos eles, no entanto, apresentaram um padrão de intervenção que é coercitivo, e que é pouco eficaz na diminuição e na eliminação de comportamentos indisciplinados. Diante dos dados analisados, há indicadores de que a emergência de comportamentos de indisciplina está relacionada à atuação didático-pedagógica dos professores. Se o professor não apresenta atividades adequadas ao tempo de aula disponível de modo a manter o aluno engajado em atividades acadêmicas, há emergência dos comportamentos indisciplinados. Ainda, a exigência de silêncio indica que os professores, em vez de estarem agindo constantemente em função do aprendizado do aluno, agem em função da manutenção da disciplina em sala de aula
185

Orientação de pais como estratégia de prevenção de problemas de comportamento infantis: revisão da literatura e proposta de intervenção segundo princípios da análise do comportamento

Abbud, Gabriella 08 April 2016 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-09-02T14:30:33Z No. of bitstreams: 1 Gabriella Abbud.pdf: 1143616 bytes, checksum: b6641b533b9c025ce7ebfd2a8db1c26e (MD5) / Made available in DSpace on 2016-09-02T14:30:33Z (GMT). No. of bitstreams: 1 Gabriella Abbud.pdf: 1143616 bytes, checksum: b6641b533b9c025ce7ebfd2a8db1c26e (MD5) Previous issue date: 2016-04-08 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Although several studies point out to the need of preventing behavioral problems in children, there are, in pertinent literature, few studies that have their focus on primary prevention of these problems, especially in Brazil. This paper presents: a review of literature on interventions with caregivers who had preventing behavioral problems in children as their goal; a critical analysis of this production and characterization of basic features that should be present in an effective and preventive behavior analytic intervention. Based on 34 descriptors, a search was conducted on the bases Science Direct and PsycINFO, which resulted in 274 articles. Subsequent analysis reduced this total to 37 articles, which are characterized, for the most part, by: describing risk factors inherent to the studied children; having conducted interventions in selective or indicated level; describing as major educational practices to be taught to caregivers the use of positive reinforcement and non-punitive procedures; being conducted in clinical setting; managing some measurement of follow-up; using the verbal report and direct observation as behavioral measure and employing group design. Based on the analysis of these studies, some important aspects to a prevention program are proposed, as regards the objectives, pre-intervention, procedures, consequences provided for parent participation and program evaluation. Finally, given a shortage of empirical research on primary prevention application programs was found, more researches on the subject are suggested / Embora diversos estudos apontem para a necessidade de se prevenir problemas de comportamento em crianças, são escassos os trabalhos publicados que têm seu foco na prevenção primária desses problemas, especialmente no Brasil. O presente trabalho apresenta: uma revisão da literatura de intervenções com cuidadores que tiveram como objetivo prevenir problemas de comportamento em crianças; uma análise crítica desta produção e a operacionalização das características que deveriam estar presentes em uma intervenção preventiva eficaz e analítico-comportamental. A busca foi realizada com 34 descritores nas bases Science Direct e PsycINFO e obteve 274 resultados. Foram selecionados para análise 37 artigos, os quais caracterizam-se, em sua maioria, por: descreverem fatores de risco inerentes às crianças; realizarem intervenções em nível indicado ou seletivo; descreverem como principais práticas educativas a serem ensinadas aos cuidadores o aumento do uso de reforçamento positivo e a não utilização da punição; serem realizados no consultório; administrarem alguma medida de follow-up; utilizarem o relato e observação direta como medida do comportamento e empregam delineamento de grupo. Com base na análise desses resultados, são propostos alguns aspectos importantes para um programa de prevenção, no que diz respeito a objetivos, pré-intervenção, procedimentos, consequências previstas para a participação dos pais e avaliação do programa. Por fim, verificou-se escassez de pesquisas empíricas com aplicação de programas de prevenção primária, de forma que se fazem necessárias mais pesquisas do tipo
186

Virtual avatars rising : the social impact based on a content analysis and a questionnaire in the context of fashion industry

Leinatamm, Kirke, Bilali, Stamatoula January 2019 (has links)
Innovative technologies and their ability to grow rapidly are known to be a great source of controversy and paranoid reactions amongst people. The aim of this research is to examine the acceptance and perception of the technology of digital supermodels and influencers. This will be done in the global market of end-users where this technology has proliferated or has the potential to emerge. Digital supermodels and influencers were regarded specifically in a marketing context for this research, since the whole essence of their existence is for marketing purposes, and was approached as a new innovative technology. The research was divided into two parts, first was about conducting a questionnaire to analyse people’s acceptance of the technology, more specifically to examine the possible change in their purchasing behaviour. The purpose of the second part of given research was to examine people’s reactions and perception towards this technology through a content analysis of Instagram comments for the Instagram accounts of digital supermodels and influencers. The addressed innovative technology of digital influencers and supermodels is mostly perceived positively or neutrally. The significant amount of neutral positions in both parts of given research states the presence of confusion and the need for answers rather than lack of interest, which is to be addressed by the creators and users of digital avatars in marketing in the fashion industry.
187

Neuropsychological and cognitive deficits in children with disruptive behaviour disorders

Shikwambana, Bob Thomas January 2006 (has links)
Thesis (M.A. (Clinical Psychology) --University of Limpopo, 2007 / Disruptive Behaviour Disorders are often associated with high rates of school drop outs, academic skills deficits and low achievement, drug abuse, low self esteem, depression, delinquency and incarceration. The main aim of the study was to establish whether children with DBDs are cognitively and/or neurologically impaired. The study investigated (1) whether children with DBDs show deficiencies in cognitive and motor functions and (2) whether gender and subtype influence cognitive and motor functions. Method: The sample of 137 children with DBDs (ADHD, ODD and CD) and those without a diagnosis of DBDs was drawn from children aged between 8 and 15 years. They were assessed using instruments that were selected to be measures of Executive Functions, cognitive functioning, and motor functions. The scores obtained from the administration of these measures were compared for significant differences between the DBD subtypes and a non-DBD control group as a possible function of gender. Results: The findings indicate that children with symptoms of DBDs performed poorer than the control group on all tests with the exception of the Digits backward. EF and motor impairments are associated with ADHD-C and ADHD-PI, and not with ADHD-HI, ODD and CD. Although among the DBDs, neuropsychological and cognitive impairments have been found to be severe in children with ADHD-PI and ADHD-C, the ADHD-C subtype showed qualitatively larger differences with the normal control group on most measures. There were no differences found between the genders in the performance on all tests that were administered. Conclusion Children of the ADHD-C and ADHD-PI subtypes are significantly more impaired on measures of Executive, cognitive and motor functions than those with ADHD-HI, ODD and CD and those without externalising disorders. However, the ADHD-C subtype found to be more severely impaired when compared with the ADHD-PI subtype.
188

破壞性創新技術的擴散模式- 以E-ink反射式顯示技術為例 / Diffusion model of a disruptive innovation technology-A case study of E-ink reflective display technology

周志豪, Chou, Chinhao Unknown Date (has links)
2007年11月全球網路書局巨擘Amazon正式宣布進軍電子書事業,發表一款名為「Kindle」的電子書以及相關營運服務,旋即造成搶購風潮。 此電子書使用E-ink公司研發的電子墨顯示技術,讓使用者的使用彷彿覺得是閱讀印刷物,而電子墨技術已存在四十餘年,最早發明於Xerox Palo Alto Research Center,此技術以使用黑白的電子墨形成可反射環境光顯示方式,有別於主流使用於筆記型電腦或桌上監視器的彩色顯示器,電子書以採反射式,能在有環境照明時清晰可視,不須要一般顯示器的背光源,所以有較低的耗電,同時也可以有較輕與薄的設計。 此差異化的顯示技術與產品定位讓E-ink創新技術花費將近十年均只有極小衆的需求,直到2008年才見有起飛的成長。 本論文透過分析E-ink個案之創新技術擴散歷程,並佐證先前相關創新技術擴散理論之文獻,闡述擴散模式、影響因素、與創新採用過程來明瞭E-ink創新擴散的驅動力。 E-ink創新技術之應用與其他創新技術的最大差異,它不僅是個破壞式創新技術,它的應用是需要改變採用者使用方式。 此類的創新技術不像其他大多數的創新技術是新增使用方式或察覺不出使用方式須改變。 所以研究其技術擴散歷程可幫助我們明瞭此類較不易擴散的創新技術如何能加速其市場擴散。此研究同時比較應用E-ink電子墨顯示技術的電子書與其他新技術與產品市場擴散之差異,包括應用高密度積體電路記憶體設計與製造技術的數位音訊播放器(MP3 player)、應用薄膜電晶體液晶顯示器技術的大尺寸液晶平面電視與應用投射式電容觸控技術的平板電腦。 本研究我們發現,E-ink創新技術的應用驅動採用者改變其以往的使用方式,而此驅動力的來源就是使用創新技術的新產品價值主張。 在此個案中更進一步發現擴散模式的兩股驅動力可改變產品擴散市場的強度,首先是技術發展達到產品可滿足客戶最低的價值主張期望,第二是此價值主張讓使用者選擇此新技術帶來創新產品的需求滿足。 延伸觀察使用方式改變的擴散主要為兩個因素的函數,一為內部推動力- 包括新技術的技術發展力、供應力。另一為外部拉引力- 包括市場對產品價值主張的吸引力、其他創新技術使用的協同效果、銷售模式與經營模式對產品的推廣能力。 創新技術是一個高科技公司維持營運與成長的重要資產,但如何能將創新技術應用於產品成功的擴散市場,若能掌握重要的驅動因子,方可將此資產較快速地轉變為倍數的財源。 本研究分析改變使用方式的破壞性創新E-ink電子墨顯示技術的擴散模式,發現初期的擴散以內部技術力與供應能力驅動為主,建議企業在此時期應思考如何應用創新技術定位產品,同時定位於最核心的價值位置建立商業模式。 在此能力逐漸增強之後,其擴散則以外部市場吸引力驅動為主,必須在市場推出所謂「殺手級應用」產品,即應用此破壞性創新技術突顯差異的產品價值主張,而能跨越採用者鴻溝。 同時建議企業在此時應著力於產品開發策略,市場推出的產品必須滿足多層次採用者不同的需求,適當的規劃產品直到技術漸趨成熟而衰退。 / It has became one of the most popular consumer electronics since Amazon, the world leading bookstore, announced to enter eBook business and launched a reading device, called “Kindle” in November 2007. This eBook device applies a simple electronic ink display technology from E-ink and let readers to view the display just like to view a printed book. This electronic ink display have been developed more than 40 years and invented in Xerox Palo Alto Research Center. This technology applies dark and white electronic ink which could reflect ambient light to display black and white image on the screen. The display don't need a backlight as conventional LCD screens, and can also be viewed under sunlight as printed paper. In the same time, it has a less power consumption and could have a slim and light design for easy carry. But, it has spent more than 10 years to only gain a small population of customers to use this differentiating display and product which apply this E-ink innovative technology. After Amazon launched “Kindle” in late 2007, we observed this technology fast diffuse to the mass market. This thesis is to study a diffusion model of E-ink disruptive technology. Review prior articles of technology diffusion theory, model of innovation diffusion, factors of innovation diffusion and adoption of innovation to understand driving forces of E-ink technology diffusion. The major difference of E-ink technology from others is to require changing the user usage method when it appy to an electroic paper. It is not only a disruptive change, but requires changing user usage experience. Most of other new technologies are to add new or be easy usage, won’t feel a change of usage method and experience. Research the diffusion model of this disruptive technology help us to understand how we could expedite this type of new technology to the market. In this study, we also compare other similar applications of new technologies, such as MP3 player which apply high density of integrated circuit memory design and manufacturing; Large sized TFT LCD TV which using TFT LCD technology; and Tablet computer which adopt capacitive touch technology. To compare those technologies market diffusion with E-ink display technology. We have found the driving force to adopt E-ink technology and make change of user usage is the value proposition of products which adapt this innovative technology. Furthermore, we conclude two driving forces to enhance diffuse into mass market. First one is to meet the minimum expectations of the value proposition from this new technology. Second is to meet the needs of users who select this new technology. In addition to, it observed two important factors to change usage adoption, one is internal push force, and the other is external pull force. Internal push forces include technology development; and capability of supply chain. External pull forces include market attraction of product value propositions; synergy for using other technologies in the products; sales and business models to promote products. Innovative technology is an important asset to sustain company growth in a high- tech company. But how it could successfully apply the innovative technology to a product and diffuse into the market? It is important to know key driving forces, so this asset is able to turn into cash for continuous funding new innovation. This study analyzes the diffusion model of a disruptive E-ink display technology. We have found early diffusion forces are depended on technology and supply chain capability. It suggests company to focus how to initiate the product position with technology capability for meeting expectation of value proposition. In the mean time, it needs to build the supply chain infrastructure to position core value of new technology. Once company has built the technology capability, diffusion forces move to market pull. It starts to launch a “killer application” product to apply this technology and underline differentiating product value proposition, so it is able to cross the “chasm”. It also suggests company to adjust strategy on product development and requires having a broader product portfolio to meet a variety of customer needs. Finally, plan product development for mainstream applications utill technology is gradually slowdown.
189

Influence of Child and Adolescent Psychopathology on Adult Personality Disorder

Ramklint, Mia January 2002 (has links)
<p>Individuals afflicted with childhood and adolescent mental disorders have an increased risk for poor outcome in adulthood. The progression of psychopathology from childhood to adult life may be influenced by a multitude of interacting variables, both biological and psychosocial. There is limited information on the relationships between child psychopathology and adult personality and personality disorders. The main aim of this thesis was therefore to gain better knowledge concerning adult personality outcome in patients with early onset of mental disorders. </p><p>Former child psychiatric patients as compared to controls had a significantly higher prevalence of all DSM-IV personality disorders (38.0 vs. 10.9 percent, p<0.001) and also a considerably higher personality disorder co-morbidity. They also had more psychosocial and environmental problems. This was exaggerated in those diagnosed with a personality disorder. Major depression, disruptive disorders and substance use disorders at a young age were strong predictors for adult personality disorder.</p><p>Patients with an early onset major depression had more personality disorders and more deviant personality traits than those with a late onset. </p><p>Forensic psychiatric male patients diagnosed with a previous conduct disorder as compared to those without had more cluster B personality disorders, and more repeated violent criminality and mixed abuse. They also exhibited more deviant personality traits and higher psychopathy scores.</p><p>The instrument "Child and Adolescent Psychiatric Screening Inventory-Retrospect" had acceptable sensitivity and specificity for assessment of child psychiatric disorders. Subscales demonstrated good internal reliability (Crohnbach´s alpha = 0.76-0.93).</p><p>The results suggest that adult personality disturbances are prevalent in individuals affected with mental problems at young ages. A better understanding of the transition of psychopathology from childhood to adulthood and a better identification of those at risk will be of help in attempts to prevent permanent impact on the adult personality.</p>
190

Life at stake when playing hide and seek : Concealing effects of prey colouration and visual backgrounds

Dimitrova, Marina January 2009 (has links)
A prey animal can use different strategies to avoid becoming eaten by predators. One such widely recognised strategy is the use of body colouration to decrease the risk of becoming detected, i.e. cryptic colouration. The principles of crypsis that I have studied are background matching, disruptive colouration and distractive markings. Further, I also studied the concealing effect of the visual background habitats. I used artificial prey items and backgrounds, and blue tits (Cyanistes caeruleus) as predators, to investigate prey concealment. In Paper I, I tested if high-contrast markings in prey coloration or in the background would result in a distracting effect. I found that such markings did increase prey search time, even when the prey markings were lighter or darker than the background. In Paper II, I studied the use of chromatic cues by predators when searching for prey. The birds easily detected prey that chromatically deviated from its background. Interestingly, background-matching prey was more difficult to detect when the colour scheme had low ultraviolet and high shortwave reflectance compared to when the reflectance bands were even. In Paper III, I studied optimisation of achromatic contrast within prey colour pattern and also the effect of shape diversity of background pattern elements on prey detection. I found that all prey types were more difficult to detect on the diverse background, but the level of contrast within prey pattern did not influence search times. In Paper IV, I further investigated how a prey should optimise its patterning with respect to background matching. I found that prey with repeated pattern elements was equally hard to detect as prey with more variable pattern. However, prey with a spatially regular pattern (aligned pattern elements) was easier to detect than prey with a spatially irregular pattern. In this paper I also found that high complexity of element shapes in the background, made the search task more difficult. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Accepted

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