Innovation hub organizations - or 'hubs' - have become a prevalent form of support for technology entrepreneurship in Africa. About 170 African hubs have been established, most since 2010. Practitioners have argued either that hubs are transformative network infra-structures for Africa's fledgling digital economy or that they are ineffective business incubators. This thesis steps back from this debate about whether hubs work. Instead, it asks how African hubs work, specifically how they shape relationships of technology entrepreneurs. Literature on intermediation and incubation is reviewed to establish a theoretical framework. The thesis then tests and extends the framework based on an extensive, grounded empirical inquiry. In-depth case study data (including 119 interviews with 133 participants) on six hubs were collected during field studies in Kigali, Harare, and Accra from September-December 2014. The thesis finds that the analyzed hub organizations were defined by nested, fluidly bounded entrepreneurial communities. Communities varied by their level of activation: mem-bers of active communities had concern for each other and recognized communities as social entities, while inactive community members only shared a loose purpose. The six hubs followed two distinct organizational patterns: the technology hub (depending on active core communities) and the entrepreneurship hub (relying on active peripheral communities). Based on these results, the thesis theorizes hubs as assemblers of technology entrepreneurs: hubs assemble previously distant and different actors into entrepreneurial communities. Assembly is unique to hubs: it is related to but different from incubation and most forms of intermediation. Assembly theory addresses important meso-level analytical gaps in prior research on the coordination and organization of entrepreneurship. The thesis underscores limitations in African technology entrepreneurship environments, advising hub practitioners to acknowledge that 'only what is there can be assembled.' Ultimately, it highlights that hubs have been critically misunderstood, and clarifies what hubs can and cannot do for technology entrepreneurs.

abstract: Food deserts are defined as regions with low average income, low accessibility to grocery stores, and high adverse health outcomes. Food deserts have thus become an important area of public health research, and many actions are being taken across the country to "solve" the variety of problems food deserts represent. Despite the many solutions promoted to improve food security, healthy food access, and health outcomes among individuals living in food desert areas, not all activities have been critically assessed for their potential for sustained impact. Further, little research has been conducted in the state of Arizona regarding food-related ‘assets’ available to employ in solutions to food desert problems. This analysis gives a glimpse into the complex nature of food deserts, which are impacted by a variety of factors, from economics to public policy to culture. It further provides a current assessment of available assets for potential use in ameliorating the negative impacts of food deserts on Arizona citizens. A graphical asset mapping analysis offers specific consideration of farmers markets and food hubs to possibly aid food deserts in the state. / Dissertation/Thesis / Masters Thesis Biology 2015

Food hubs, a new model of values-based agro-food enterprise, are promoted by their advocates as a means to simultaneously improve the livelihoods of small and mid-sized farmers, increase the social and environmental sustainability of the food system, and supply the ever increasing consumer demand for health, local food. Noting the contradictions embedded in the promise of simultaneously generating both social values and economic value, this study explores how goals of promoting positive social, economic, or environmental change are achieved and/or inhibited when implemented though marketbased activities. Through a series of three in-depth case studies of food hubs in the Southeastern United States, the three papers compiled in this dissertation investigate how food hubs work to realize abstract non-financial goals (e.g. ‘helping family farmers’, ‘promoting sustainable food systems’) through the mundane work of food aggregation and distribution. Particular attention is paid to the experiences of mid-sized farmers who participate in food hubs, and the historic, material, and subjective processes that influence the development of food hubs and their many stakeholders. Highlighting the tensions and negotiations inherent to the hybrid social-and-monetary work of food hubs, I assert the need for an analytical framework that can account for the more-than-financial dimensions of economic and ethical praxis. To that end, I draw on the theories of J.K. Gibson-Graham to suggest that food hubs are best understood as a form of post-capitalist enterprise situated within a community agro-food economy, wherein reciprocal and interdependent relationships are forged between new economic subjects through deliberate and ongoing negotiation of care via the process and outcomes of diverse economic activity.

The aviation industry worldwide is changing dynamically in reaction to trends such as globalisation and with the need to increase market share to remain competitive. The African aviation industry still faces many problems in the institutional, technical and operational areas. Despite its potential for enhancing economic development, air travel to and from Africa remains a small percentage of world air travel. The African air route network is characterised by sparse demand, with long sector distances, low frequencies and high fares. This study investigates cost-effective hub-and-spoke (H&S) network design strategies for the African route network. An H&S network would minimise the cost of air transport and improve accessibility and connectivity. The study challenges the typical characteristics of H&S networks which are usually found in denser route networks. The design methodology used was the one most appropriate for the African region, using the datasets and tools available. As a first-cut analysis for Africa, the results of the research contribute to understanding the effectiveness of H&S networks in markets with sparse demand. A cost model previously developed by the author to calculate operating costs on a route was used. It eliminated the need to assume discount coefficients on links, as passenger demand increases, in a field with limited data. The cost indicators derived from the model were used as criteria for choosing the most efficient hubs within a cluster. These were compared with the hub location criteria in the literature which use distances and passengers. It was found that using the cost indicators gives a reasonably consistent method that lowers passenger travel time. The optimum number of clusters and hubs was found to be four. The geo-political network design method yielded the lowest network costs. The hubs are centrally located within the clusters: Morocco in the north, South Africa in the south, Kenya in the east and Nigeria in the west. They are characterised by high passenger demand and short node-hub sectors. There are significant benefits to be gained from using this hub network design, resulting from the economies of scale with higher passenger densities on routes. Furthermore, the benefits of higher service frequencies and better connectivity outweigh the extra travel time when routing through hubs. The study found that for sparse networks, the cheapest hub-location options have high passenger demand. The sector distance is crucial in lowering operating costs as smaller, more efficient short range aircraft can be operated. It is therefore more efficient to assign nodes to the closest hub to lower node-hub costs. The optimum number of hubs/clusters is thus determined by the distance threshold for the efficient aircraft. The effect of changing the cluster boundaries on network costs also depends on the change in node-hub distances between the clusters. As sparsity reduces, the economies-of-scale benefits outweigh the increasing operating costs of longer distances, allowing efficient operation of larger-capacity aircraft. This means that the location of the hubs and the number of clusters becomes more flexible, implying that node-hub links can become longer, reducing both the clusters and the number of hubs. / Thesis (PhD)--University of Pretoria, 2008. / Civil Engineering / PhD / Unrestricted

This dissertation investigates the evolution of Kenya’s Internet communication technology (ICT) ecosystem and explores the barriers and subsequent enabling processes encountered when growing an ICT ecosystem in a resource-scarce context. Drawing upon 12 in-depth case studies of Kenyan tech entrepreneurs and 45 interviews with technology experts this dissertation provides a holistic perspective on the barriers and enablers that Kenyan technology entrepreneurs encounter across the areas of culture, human capital, finance, policy, entrepreneurial support systems, and markets. Together with relevant theory on how ecosystems emerge and advance the thesis develops a model that explains how ICT ecosystems can emerge in resource-scarce contexts. The model shows how locally available enabling processes may be drawn on to substitute and establish missing condition factors. Furthermore, this dissertation analyzes mobile technology's potential to tackle unemployment in Kenya and provides a critical evaluation of the embedded economic and developmental opportunity.:1. Introduction 1 1.1 The potential of mobile technology to tackle unemployment in Kenya 1.2 Kenya’s emerging “Silicon Savannah” 1.3 Introduction to the research context 1.3.1 Country Context: Kenya the East-African economic hub and its unemployment challenge 1.3.2 The “Silicon Savannah”: Kenya’s ICT entrepreneurship ecosystem 2. Literature chapter 2.1 Basic theoretical concepts 2.2 Mobile for development 2.2.1 Mobile for development fields 2.2.2 Critics of the M4D stream 2.2.3 Contextual challenges faced by M4D initiatives 2.3 Mobile for work (mWork) 2.3.1 The Virtual Economy: A market for virtually traded scarcities 2.3.2 Mobile Micro Work 2.3.3 Mobile for Recruitment 2.4 The ecosystem view on entrepreneruship 2.4.1 Theoretical basis: Cluster Theory and Regional Innovation Systems Theory 2.4.2 Distinguishing features of Entrepreneurship Ecosystem functioning 2.4.3 Emergence and development of ICT entrepreneurship ecosystems over time 2.4.4 The role of Policy in fostering EE growth 2.5 The context for entrepreneurship in Kenya 2.6 Technology entrepreneurship in Kenya: Challenges faced in the Silicon Savannah 3. Methodology Chapter 3.1 Research Design 3.2 Data collection and access 3.2.1 mWork sample selection 3.2.2 Interview conduct with mWork and other local ICT entrepreneurs 3.2.3 Sample selection and interview conduct with “Silicon Savannah” experts 3.3 Data Analysis 3.3.1 Interview data analysis 3.3.2 Case analysis: within case and cross case analysis 3.3.3 Development of the Model of Ecosystem Emergence 3.4 Measurement of mWork development impact 3.5 Other Methodological Considerations 3.5.1 Researcher‘s Role 3.5.2 Ethical Considerations 3.5.3 Credibility of findings 4. mWork in Kenya 4.1 Introduction: mWork in Kenya 4.2 Case presentation 4.2.1 mWork segment: Market Research 4.1.2 mWork Segment: Recruiting 4.2.3 mWork Segment: Mobile Micro Work 4.2.4 mWork segment: Market intermediaries 4.2.5 Overview of mWork Cases 4.3 Cross-case analysis 4.3.1 Feasibility of mWork approaches and challenges faced 4.3.2 Feasibility of business models suggested by literature in a Kenyan context 4.3.3 Overcoming challenges to mWork in Kenya: Four successful examples 4.4 Development impact of mWork 4.4.1 Development impact of mWork Segment Mobile Micro Work 4.4.2 Development impact of mWork segment market research 4.4.3 Development impact of mWork segment recruiting 4.4.4 (Potential) development impact of mWork segment: Market intermediary 5. The Kenyan “Silicon Savannah” 5.1 Empirical Findings: Barriers and enablers to technology entrepreneurship in Kenya 5.5.1 Ecosystem dimension: Culture 5.1.2 Ecosystem dimension: Supports 5.1.3 Ecosystem dimension: Human capital 5.1.4 Ecosystem dimension: Finance 5.1.5 Ecosystem dimension: Policy 5.1.6 Ecosystem dimension: Markets 5.2 Discussion of findings in the wider discourse of the Silicon Savannah 5.3 The unique nature of the phenomenon of technology entrepreneurship in Kenya 5.4 Main growth barriers in the “Silicon Savannah” and ICT EE s in the GS 5.5 Main growth enablers in the “Silicon Savannah” and early ICT EE s in the GS 5.6 Development trajectory of ICT EE s in resource-scarce contexts 6. Conclusion 6.1 Conclusion on the opportunity of mWork in Kenya 6.1.1 Summary of main findings 6.1.2 Theoretical implications 6.1.3 Practical implications 6.1.4 Limitations and further research 6.2 Conclusion on Kenyas “Silicon Savannah” 6.2.1 Summary of main findings 6.2.2 Theoretical implications 6.2.3 Practical implications and recommendations 6.2.4 Limitations and further research References Appendix

The original study on which this study was based on was conducted by Jacob Goldenberg, Sangman Han, Donald R.Lehmann, and Jae Weon Hong and published in 2009. In a slight contrast to Goldenberg et al (2009), this study was conducted among a bottom of the pyramid (BOP) network in South Africa using one non discretionary product whilst the original study was conducted on multiple high tech products in Korea This study explores the role of hubs (people with an outstanding number of social ties) in diffusion and adoption of products. The study was conducted using data on a large network and its adoption of a product (electricity) to identify two types of hubs – innovative and follower hubs and their role in influencing adoption ala Goldenberg et al (2009). Even though hubs are not necessarily opinion leaders nor are they necessarily innovators (as described by Rogers, (1962)) they tend to adopt earlier in the diffusion process. Innovator hubs have a greater impact on speed of adoption whilst Follower hubs have greater impact on the size of the market or total number of adoptions. Interestingly and crucially this early adoption behaviour of hubs can be a useful predictor of future product success. Among BOP network nodes, relationships and trust are important in determining the amount or degree of influence one can exert on a fellow network member. Homogeneity increases trust which in turn impacts the role of a hub as a force of influence. The centrality of hubs to networks is also a factor behind their role as information to the rest of the network passes through them, to a degree giving them control over the dissemination of information. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted

The concept of a hub airport has evolved widening its scope as a national civil aviation policy-making tool, due to the ability to deliver wider socio-economic benefits to a country. However, not all airports can be converted into hubs. This research proposes a methodological approach to structural analysis of the airport industry, that could be applied to determine the competitive position of an airport in a given aviation network and devise airport strategies and national policy measures to improve the current position of the airport. This study presents a twelve-group taxonomy of airports, which analyses the changing geography of the airport industry in the East (Asia and The Middle East). Multivariate data have been used in a two-step Agglomerative Hierarchical Clustering exercise which represents three airport strategies: namely, degree-of-airport-activity (size and intensity of operations), network strategies (international and domestic hub), and the market segmentation strategies (service and destination orientation). Principal Component Analysis has been utilised as a data reduction tool. The study confirms the general hypothesis that a sound macro environment and liberalised approach to economic regulation in the air transport industry are important for successful hub operations. In addition, it sheds light on the fact that while the factors of geographical advantage, economic development, urbanisation, tourism and business attractiveness, physical and intellectual infrastructure, and political and administrative frameworks, are all basic prerequisites (qualifiers) for successful hubbing in the region, those factors would not necessarily guarantee a hub status unless the governments are also committed to develop the sector and take timely decisions (differentiators) to allow airports to benefit from the first mover advantage. Application of the proposed taxonomy was tested on a case study of the major international airport of Sri Lanka, to provide policy inputs to develop the airport that is currently identified as being overshadowed by the mega hubs in the region.

人脈理論相關的文獻,尤以 Granovetter(1973)提出非常優雅的「弱連結 (weak tie)」一詞最為經典,他的論文發現經由弱連結介紹新工作的成功率高於 強連結,同時提出弱連結相較於強連結(strong tie)更多元,因此弱連結對宏觀世 界的效益必大於強連結。而後 Rogers(2006)也在創新的擴散中提出弱連結應 該屬於異質性連結,強連結則屬於同質性的連結,異質性不容易連結卻對擴散的 影響更大。因此本研究的動機將以弱勢的創業家為研究對象,探討弱連結擴散的 動機與擴散方法,並回答研究問題弱連結的擴散效益為何? 本研究發現弱連結的脆弱並不全然是異質性不易溝通之故,因為弱連結與強連結最大的不同是強連結靠關係遠近產生連結,弱連結則是自願性的連結居多,因此創業家的創夢才是真正點燃連結的起源,此外弱連結的橋樑特質是喜好轉介稀有性消息,產生消息經濟的效益而達到更廣泛的連結,因此研究者認為弱連結應用於創新擴散將有三點效益,第一點是弱連結因為自發性動機與可被信任的第三方而提高傳遞意願,第二點是弱連結以泛泛之交居多,他們喜好轉介稀有性消息,因此提高傳送廣度,最後發現所謂的六度分隔除了代表差異性人脈將造成平 均為六的結果外,也代表著六個人脈圈,本研究因此發現第一度的人脈差異將影 響網際網路時代的小世界接受率。 而對於創業家以弱連結來進行創新擴散,研究者認為實務上建立異質性創業 團隊將有助於進入不同特質的弱連結樞紐區,此外創業家勇於發表創夢的想法, 其心態越開放也有助於凝聚弱連結,因此創業家可以藉由社群網站或部落格等媒 體建立自行發聲的管道,將有助於幫助創業家位於樞紐中心,強化擴散的能力。 研究者在回顧文獻後也發現,弱連結在開放式網絡下的橋樑特質與效益被後來學 者忽略,同時隨著網際網路興起帶來多元的媒體與開放式人際關係,研究者認為 將更有助於觀察弱連結對創新擴散的幫助,本研究觀察 Apps 產業裡 Bonnie’s Brunch 個案後,經由八位訪談者與半年的網路社群媒體追蹤的結果,發現弱連 結的橋樑功能是資訊的聚集處,也是連結的捷徑,因此擁有對的連結的確是很重要的事,但是弱連結卻未必時常擔任善意的陌生人,因此弱連結的連結困難在於弱連結的自願性動機,因此研究者在理論貢獻部分提出弱連結的力量來源為自願性的動機,這股隱性的力量唯有受到單純動機的點燃才能爆發出來,因此創業家成功的方程式還有一項無法被操控的弱連結影響力,唯有創業家經過長期的耕耘,持續提供資訊交換,才能與弱聯結維繫關係。 / Among the personal network theory related literatures, the elegant term “weak tie” proposed by Granovetter(1973) is the most classic theory. His thesis paper finding shows that the success rate of introducing new jobs through a weak tie is higher than that of a strong tie. Hence, he believes that as the macroscopic view of the world’s weak tie is more diverse than the strong tie, the benefits produced after creating the tie are definitely greater than the strong tie. Rogers (2006) later proposed in diffusion of innovation that the weak tie is the tie of heterogeneity, while the strong tie is the tie of homogeneity. Heterogeneity does not easily produce a tie, but it has a greater impact on diffusion. Therefore, the weak tie diffusion motivation and diffusion method were explored in this study, and the research problem, i.e., the diffusion benefits of the weak tie, was answered. It was found in this study that the vulnerability of the weak tie is not entirely due to the communication difficulty of heterogeneity, because the greatest difference between the weak tie and strong tie lies in the fact that strong ties produce ties depending on the distance of a relationship, while weak ties are generally voluntary ties. Hence, entre- preneurs’ building of dreams is the actual source that triggers ties. In addition, the weak tie bridge is characterized by a preference to prefer rare news, Newsonomics, and achieve more extensive links. Thus, the researcher believes that there are three benefits when the weak tie is applied in diffusion of innovation. First, the weak tie enhances the willingness to convey messages due to its own voluntary motivation and trustworthy third party. Second, weak ties are generally formed by acquaintances. They prefer to refer rare news, thus the broader conveyance. Lastly, it was found that the so-called six degrees not only represents differential personal networks that result in the outcome of six on average, but also represents six network circles. It was therefore found in this study that the first-degree personal network will affect the small world acceptance rate in the Internet age. As for entrepreneurs, they engaged in diffusion of innovation through weak ties. The researcher believes that, in practice, the establishment of the entrepreneurial team of homogeneity is conducive to entry into weak tie hubs of different characteristics. In addition, entrepreneurs had the courage to express their ideas about building dreams, and their open-mindedness also contributed to the gathering of weak ties. Hence, it is suggested that entrepreneurs establish channels to voice themselves through communi- ty networks, BLOG, and other medias, which will help them stay in the hub and strengthen their ability to diffuse. Through literature review, the researcher found that the bridging characteristics and benefits of the weak tie in the open-type network had been neglected by subsequent researchers. At the same time, the rise of the Internet has brought about a diversity of media and open-type interpersonal relationships, which is believed to be more helpful for weak ties to contribute to diffusion of innovation. Through observations made on the entrepreneurs of Bonnie’s Brunch in the App industry, the results of interviews with 8 individuals, and long-term tracking of Internet community media, it was found that the bridge of the weak tie is a gathering place of information and it is also a shortcut of ties. Therefore, having the right links is indeed important. However, the weak tie is not always willing to serve as the stranger that displays goodwill. The difficulty in linking weak ties therefore lies in the voluntary motivation of the weak tie. In the researcher’s theoretical contributions, it was mentioned that the source of the weak tie force is the voluntary motivation, and this implicit force can only explode after igniting pure mo- tive. Therefore, the successful equation still possesses the influence of the weak tie that cannot be manipulated. Only through long-term cultivation of entrepreneurs and con- tinuous provision of information exchanges to maintain the relationships with weak ties.

Many diseases, such as cardiovascular diseases, cancer and diabetes, originate from several malfunctions in biological systems. The human body is regulated by a wide range of biological systems, composed of biological entities interacting in complex networks, responsible for carrying out specific functions. Some parts of the networks, such as hubs serving as master regulators, are more important for maintaining a function. To find the cause of diseases, where hubs are possible disease regulators, it is critical to know the structure of these biological systems. Such structures can be reverse engineered from high-throughput data with measured levels of biological entities. However, the complexity of biological systems makes inferring their structure a complicated task, demanding the use of computational methods, called network inference methods. Today, many network inference methods have been developed, that predicts the interactions of biological networks, with varying degree of success. In the DREAM5 challenge 35 network inference methods were evaluated on how well interactions in gene regulatory networks (GRNs) were predicted. Herein, in contrast to the DREAM5 challenge, we have evaluated network inference methods’ ability to predict hubs in GRNs. In accordance with the DREAM5 challenge, different methods performed the best on different data sets. Moreover, we discovered that network inference methods were not able to identify hubs from groups of similarly expressed genes. Also, we noticed that hubs in GRNs had a distinct expression in the data, leading to the development of a new method (the PCA method) for the prediction of hubs. Furthermore, the DREAM5 challenge showed that community predictions, combining the predictions from many network inference methods, resulted in more robust predictions of interactions. Herein, the community approach was applied on predicting hubs, with the conclusion that community predictions is the more robust approach. However, we also concluded that it was enough to combine 6-7 network inference methods to achieve robust predictions of hubs.

Shared mobility is considered a more sustainable alternative to private modes. Nonetheless, its sudden and sometimes “out of control” emergence poses issues that need to be addressed. Lack of regulations and public space mismanagement cause sidewalks and city roads to be overcrowded with shared vehicles (especially in the case of micromobility). This causes nuisance and safety concerns and hinders the societal benefits shared mobility may provide. Shared mobility hubs have the potential to address these issues. The research was carried out within the context of the SmartHubs project, an EIT Urban Mobility project initiated in 2021 by a diverse consortium of 7 cities, companies, and universities to develop and validate effective and economically viable mobility hub solutions. This degree project aims to improve the Decision-Support-Tool (DST) developed by SmartHubs to identify locations of shared-mobility hubs having high potential in driving sustainable travel usage. To achieve that, the thesis proposes a methodology for determining smart hub locations and their corresponding utilities based on the combination of GIS cluster analysis of free-floating shared mobility parking patterns and a stated-preference study. The potential hub locations were determined from the cluster analysis of free-floating trip characteristics. Using the stated preference survey data, the thesis develops a model to estimate the probability of parking at the hub as a function of explanatory variables, including walking distance, reward policies and the parking situation. The model testing results showed that the proposed methodology can well predict the hub (usage) demand and improve the current DST originally developed in the SmartHubs project.