87 research outputs found
SIMBA: scalable inversion in optical tomography using deep denoising priors
No full textTwo features desired in a three-dimensional (3D) optical tomographic image reconstruction algorithm are the ability to reduce imaging artifacts and to do fast processing of large data volumes. Traditional iterative inversion algorithms are impractical in this context due to their heavy computational and memory requirements. We propose and experimentally validate a novel scalable iterative mini-batch algorithm (SIMBA) for fast and high-quality optical tomographic imaging. SIMBA enables highquality imaging by combining two complementary information sources: the physics of the imaging system characterized by its forward model and the imaging prior characterized by a denoising deep neural net. SIMBA easily scales to very large 3D tomographic datasets by processing only a small subset of measurements at each iteration. We establish the theoretical fixedpoint convergence of SIMBA under nonexpansive denoisers for convex data-fidelity terms. We validate SIMBA on both simulated and experimentally collected intensity diffraction tomography (IDT) datasets. Our results show that SIMBA can significantly reduce the computational burden of 3D image formation without sacrificing the imaging quality.https://arxiv.org/abs/1911.13241First author draf
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The process of developing innovative capabilities in biotechnology: the case of UK firms
No full textThe advent of born-global bio-tech firms signal the genesis of a new business model that is emerging in the biotechnology sector. Born globals are small firms whose knowledge supply-chain includes global resources from multiple countries. Their innovation ‘ecosystems’ consists of experienced scientists, science parks, academics, well-established bio-pharmaceutical firms and government institutions. The firms plan their business based on global strategic perspectives and this significantly increases their productivity and innovativeness. But surprisingly, little is known about their capability development processes in the specialised networks of the biotechnology sector. As a result, this study explores the connectivity of various elements, within their knowledge supply-chain, and how they influence their capacity to generate new scientific knowledge and technical know-how. The study employs a multi-case approach. It examines five cases of bio-tech firms from the East Midlands region of the United Kingdom which have an entrepreneurial flair synonymous with born-global firms. The findings from within and across cases, secondary data analysis and results from a ‘pilot study’ led to the construction of a new conceptual framework of knowledge and innovative capability development. The model is created from the ideas of Freeman and others and it contributes to an understanding of the concepts of dynamic capabilities and network theories
Perancangan Website Sebagai Media Promosi Dan Penjualan Pada CV Simba Jaya Magelang
No full textABSTRACT - Simba CV Jaya is one of the few providers of goods of daily needs of society in general. Conventional sales methods still make the information less widely accessible. Making a website titled Designing Website As Media Promotion and Sales at Simba Jaya CV Magelang is expected to improve the promotion, sales and enable customers to order products. In making the website the author uses the method of data collection among others by observation, interviews, and literature. While the software development method uses four stages, with the waterfall method of software that includes analysis, design, code generation and testing program. The purpose of making a website is to enable customers to access information or transactions and increase the consumer appeal of the product is marketed.
Keywords: websites, e-commerce, promotion, sales, CV Simba Jaya
ABSTRAKSI - CV Simba Jaya merupakan salah satu dari beberapa perusahaan penyedia barang kebutuhan sehari-hari masyarakat pada umumnya. Metode penjualan yang masih konvensional menjadikan informasi kurang luas untuk diakses. Pembuatan website dengan judul Perancangan Website Sebagai Media Promosi dan Penjualan pada CV Simba Jaya Magelang diharapkan bisa meningkatkan promosi, penjualan serta memudahkan konsumen dalam melakukan pemesanan produk. Dalam pembuatan website penulis menggunakan metode pengumpulan data antara lain dengan cara observasi, wawancara dan studi pustaka. Sedangkan metode pengembangan perangkat lunak menggunakan empat tahap yaitu dengan metode waterfall yang meliputi analisa perangkat lunak, desain, pembuatan kode program dan pengujian. Tujuan pembuatan website ialah untuk memudahkan konsumen dalam mengakses informasi atau transaksi serta meningkatkan daya tarik konsumen terhadap produk yang di pasarkan.
Kata Kunci: website, e-commerce, promosi, penjualan, CV Simba Jay
A matter of entrepreneurial decisions: Dairibord Holdings Limited (DHL) in Zimbabwe, Emerald Emerging Markets Case Studies, Vol. 8 Issue: 3
No full textNumerical estimation of EMI impact on implantable cardiac pacemakers in elevator using EMF distributions inside human body
No full text© 2010 IEEE. Reprinted, with permission, from Hikage, T., Nojima, T., Simba, A.Y., Watanabe, S., Numerical estimation of EMI impact on implantable cardiac pacemakers in elevator using EMF distributions inside human body, 2010 IEEE Antennas and Propagation Society International Symposium (APSURSI), Jul. 2010. This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of Hokkaido University products or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it
Measuring and Creating Cognitive-Behavioural Associations: Testing a Social Identity Model of Behavioural Associations (SIMBA)
No full textIn 2014, author and speaker Tom Asacker presented the popular TED talk entitled “Why TED Talks don't change people's behaviors”—arguing that lasting behavioural change is only truly achievable by appealing to an individual’s identity and self-concept. His message, that “who we think we are, is why we do what we do” is fundamental to Social Identity Theory (Tajfel, 1978; Tajfel & Turner, 1979, 1986)—which posits that we derive an essential part of our self-concept from our group memberships. Rather than being external to the self, our group memberships and their content—including the consensual perceptions of what is normative for a given group—are internalised within the self-concept in the form of social identities (Tajfel, 1981; Turner, 1982, 1985). Properties of the social group, such as group norms, become subjectively interchangeable with personal norms and stereotypes—influencing thought and guiding action. Our social identities therefore provide some insight into who we are, what we think, and what we do (Abrams et al., 1990; Oakes et al., 1994; Reicher, 2001). Social identities are not only important in describing where we sit within our perceived social reality, but also in predicting what we will become; identities have the power to shape and change our future behaviour (Reicher, 2001).
Implicit in both this messaging and social identity theorising is the suggestion that this relationship between social identity and behaviour may not be so straight forward; while it is true who we think we are contributes to how we behave, equally, the way we behave—and the extent to which it is seen to be normative for a given group—guides the groups we identify with. Therefore, our behaviour has implications for our self-concept. The acquisition of self-knowledge in this fashion is fundamental to theories of cognitive consistency—such as self-perception theory (Bem, 1972)—which posit that individuals infer their own attitudes, beliefs, and other internal states from observing their own behaviours and the circumstances under which they occur (Bem, 1972). For example, when a university student repeatedly engages in behaviours seen to be normative of the student identity—such as drinking (Davoren et al., 2016; John & Alwyn, 2014)—they may begin to reflect on this congruency between their own behaviour and the behaviour of other students. Over time, this individual may begin to identify more strongly as a student, as they perceive their behaviour to align with what it means to be a student. Failing to engage in such behaviours might (over time) even lead to disidentification from the group. This reciprocal causality is consistent with theories and research that examine the wider associative network of the self-concept (Greenwald & Pratkanis, 1984; Koffka, 1935), and has been modelled in relation to other social psychological constructs such a attitudes and self-esteem (e.g., the balanced identity design; Greenwald, Banaji, Rudman, et al., 2002, Dunham, 2013).
While traditional and contemporary theories of social identity have focused primarily on different bivariate relationships among social identity, group norms and behaviour, these relationships are yet to be unified in a single, dynamic model that theorises how the interrelations among these self-relevant constructs emerge and are maintained. This thesis presents, and comprehensively tests, a Social Identity Model of Behavioural Associations (SIMBA)—a theoretical and methodological integration of both social (Tajfel, 1978; Tajfel & Turner, 1979; Turner et al., 1987) and balanced identity theorising (Greenwald, Banaji, Rudman, et al., 2002)—which models the relationships among social identification, group norms, and individual-level behaviour as reciprocal associative links in a triangular constellation.
Throughout the thesis, the SIMBA is used explore two overarching research questions. First, we determine whether identity, norms, and behaviour can be measured—not only directly (i.e., via self-report), but also indirectly (i.e., via implicit measures) as cognitive associations among self-group, group-behaviour, and self-behaviour concepts. We also establish whether the three constructs demonstrate a mutually interactive relationship; that is, whether any one of the constructs may be explained by the interaction between the remaining two. Second, we aim to demonstrate reciprocal causality; beyond describing interactive relations among concepts, the SIMBA assumes that each construct is not only explained, but predicted by the remaining two. Therefore, we explore the cognitive processes through which identity, norms and behaviour are created, and determine whether cognitive balance emerges among them. Ultimately, the thesis tests the utility of the SIMBA as a theoretical framework for understanding the relation between, and the formation of, social identity, group norms, and individual-level behaviour.
In Chapter 1, we review the relevant theories that underpin the theoretical and methodological assumptions of the SIMBA, that is, the theories relevant to the social identity approach (i.e., social identity theory and self-categorisation theory) and cognitive consistency (i.e., balance theory and balanced identity theory). These theories are discussed in terms of their origins and fundamental principles, while also highlighting the ways in which they have inspired and contributed to the development of contemporary theories in their respective fields. With regards to the social identity approach, we discuss how traditional social identity theorising has advanced through the development of models that consider social identity and group norms to be mutually interactive and influential in the formation of one another. Regarding theories of cognitive consistency, we discuss the way in which these theories have become increasingly broad in their applicability and explanatory potential—explaining cognitive balance in a variety of contexts such as interpersonal relations, social identity, and intergroup attitudes.
In Chapter 2, we provide a theoretical overview of the SIMBA. The theory’s key predictions regarding measuring associations, creating associations, and changing associations are outlined, alongside the supporting literature that aided in their development. This chapter also discusses the ways in which the SIMBA theoretically and methodologically advances both SIT and BIT by drawing direct comparisons between the theories. This chapter ends with an overview of the thesis, which highlights the specific research questions that will be addressed in each empirical chapter, and the progression of ideas across chapters.
Chapters 3 and 4 focus on testing the utility of the SIMBA for the measurement of self-group-behaviour associations. Across these chapters, we investigate the primary assumption of the SIMBA (i.e., the balance-congruity principle; that the strength of any one association in the SIMBA can be predicted by the interactive strength of the remaining two) in relation to a variety of group memberships and behaviours—establishing the generalisability of the SIMBA.
In Chapter 3, we tested the SIMBA in the context of drinking behaviour in relation to student (Studies 1 and 2) and British national (Study 3) identities. These studies identified good support for the balance-congruity principle on implicit measures of social identity, group norms, and behaviour. Evidence for this prediction was weaker on explicit scale measures; we argue that this difference may be dependent on the explicit measures possessing theoretically meaningful zero-points.
In Chapter 4, we tested the SIMBA in the context of social distancing behaviour in relation to the British national identity. Study 4 included two different types of explicit measure (e.g., traditional Likert-type scales and visual analogue scales); confirming that support on explicit measures was strong, and equal to that on implicit measures, when using visual analogue scales (i.e., measures that possess a zero-point indicative of associative indifference). We also assessed balance-congruity across two timepoints during the COVID-19 pandemic—finding cognitive balance to be stable over time.
In Chapter 5, we step back from directly testing the assumptions of the SIMBA and adopt a network analytic approach to understanding the different social identities found to co-occur within individuals, and the behaviours thought to correspond with specific identities. This research was initially developed to help identify associated groups and behaviours to feature in future tests of the SIMBA—particularly for the measurement of associations, following on from Chapters 3 and 4—but the co-occurrences identified also serve as a meaningful resource for those conducting research into identities and their associated behaviours more generally. Therefore, while the chapter may appear to divert from the SIMBA narrative, it has an important function in progressing the theory (e.g., establishing its wider generalisability to multiple groups and behaviours), and social identity research more broadly. In Study 5, we generated three different network-types—identity-by-identity, behaviour-by-identity, and identity-by-behaviour—where we identified several identities and behaviours to significantly co-occur at a rate both higher and lower than chance. Although the overall structure of the networks was found to be significantly different than expected by chance, networks were low in modularity (i.e., there was no evidence of clustering within the data).
In the final empirical chapter (i.e., Chapter 6) we focus on testing the utility of the SIMBA for the creation of novel self-group-behaviour associations. In two pilot studies, we established the initial efficacy of both the partial-IAT and probabilistic learning tasks for generating associations among concepts. After refining these methodologies, Study 6 directly compared them, and conducte
Diaspora networks: a social capital source for entrepreneurship in low-income and emerging economies in Africa
No full textTrust-building mechanisms in group-based microfinance: a Cameroonian perspective
No full textWhile trust is critical to microlending groups, much less is known about the vital factors and mechanisms that foster its emergence in microlending groups. This paper examines the practices of trust building and use in microlending groups. The results suggest that trust is produced and developed in microlending groups through a combination of calculative, prediction, intentionality, capability and transference mechanisms. These mechanisms are not mutually exclusive but act together to build trust. Though trust has general characteristics, whether and how it is formed and developed in microlending groups depends on contextspecific factors such as informal debt relations. Trust among group members is bolstered by multiplex relations of social events, neighbourhood, and friendship. The paper suggests that the unbanked population has a rich informal credit history
Fostering micro-entrepreneurs' structural and relational social capital through microfinance
No full textThis paper uses a multi-dimensional perspective on social capital to investigate how a microfinance institution can enhance the social capital of poor entrepreneurs. Findings show that by creating an environment that encourages frequent meetings and interactions between borrowers, group-based microfinance facilitates the development of relational trust and expansion of the network size of micro-entrepreneurs. An increase in levels of structural and relational social capital, in turn, leads to numerous advantages in terms of the flow of a diversity of resources. Ensuring access to financial capital, creating an enabling environment that fosters structural and relational social capital, and providing training would constitute a much better approach to helping poor entrepreneurs
Engaged scholarship: encouraging interactionism in entrepreneurship and small-to-medium enterprise (SME) research
No full textPurpose: The purpose of this paper is to introduce a multi-layered theoretical framework to enable engaged scholarship to develop as a practice in entrepreneurship and small business research. To do so, it illuminates the salient features of engaged scholarship, collaborative learning and actor-network theory (ANT).
Design/methodology/approach: The paper follows a narrative or traditional literature review design. Specifically, it adopts a thematic approach for summarising and synthesising a body of literature on engaged scholarship, collaborative learning and ANT with the view to develop a new multi-layered theoretical framework.
Findings: Applying the theory of engaged scholarship to pivot entrepreneurship/SME research provides scholars with an opportunity to unlock the theory vs practice paradox. Moreover, engaged scholarship offers valuable instructions for encouraging interactionism between entrepreneurship researchers and practitioners as well as reconcile their polarised views. Co-production and co-creation of knowledge addresses the concerns often raised by the practitioner community regarding the relevance and applicability of academic research to practice.
Practical implications: The proposed multi-layered framework provides entrepreneurship researchers, and the practitioner community with a taxonomy to use to encourage a joint approach to research. Developing deep partnerships between academics and practitioners can produce outcomes that satisfy the twin imperatives of scholarship that can be of high quality as well as a value to society.
Originality/value: The paper advances the theory and practice of engaged scholarship in new ways that are not common in entrepreneurship/SME research. This enables engaged scholarship to develop as a practice in entrepreneurship and small firms’ research. Through applying the proposed multi-layered framework in research, academics can deliver fully developed solutions for practical problems. The framework is useful in the theory vs practice and entrepreneurship researchers vs practitioner debates
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