The Surface energy Balance System (SEBS) was utilised for evaluating the spatial and temporal variation of the actual evapotranspiration (ETa) over the Gumara basin, using satellite images from Moderate-resolution Imaging Spectroradiometer (MODIS) in combination with meteorological data of the study area, for 12 days of 2006, 6 corresponding to the dry season, and 6 corresponding to the rainy season. The daily ETa was estimated for these days, and then a simple extrapolation of ETa proportionally to the ETp was used to compute the monthly and annual ETa. SEBS estimated an average ETa of 0.84 mm/day for the 6 dates of January, and an average of 4.24 mm/day for the 6 dates of the rainy season. The lowest value was obtained in Jan 2nd, with 0.73 mm/day, and the highest was observed in Sep 21st. Monthly ETa showed the lowest value of 34.20 mm in February; whereas the highest was observed in June with 115.67 mm. The annual ETa was about 847.12 mm, for the 2006. The average ETp estimated for the 12 analysed dates by Pan Evaporation method was about 4.15 mm/day, whereas for the Penman Monteith method was approximately 4.22 mm/day. Particularly for the rainy dates, the daily ETa was very similar to the ETp, with an average difference of 0.16 mm/day. In the water balance method, the difference between the estimated runoff with the ETa by SEBS, and the measured runoff at the station was of approximately 175.60 mm/year. According to these results and, although there are uncertainties associated with the model and the inputs utilised, the SEBS seemed to estimate reasonable values of ETa for the study area.

The classical job-shop problem is among the most studied scheduling models because it can model a variety of real-life applications. This problem can be reinforced by integrating the operation flexibility to obtain a more realistic model, called Flexible-Job shop Scheduling Problem (FJSP), that capture the salient features of modern systems. To consider both productivity and customer service in the FJSP, objective function such as regular criteria that consider an increasing function of the completion times of the jobs are needed. Makespan consists of minimizing the maximal completion time of all jobs, and it is the most studied criterion in the FJSP. However, minimizing other regular criteria are better suited to capture critical factors that affect the profit of manufacturing and service systems and thus their competitiveness; in particular the importance of jobs(customers) with weighted criteria. This thesis presents innovative general local search approaches to minimize regular criteria in the FJSP in two ways: Single criterion and multi-criteria called Multi-Objective Flexible Job-shop Scheduling Problem (MOFJSP). The local search approaches make use of a generalization of the disjunctive graph model, iteratively progress from one solution to another using two neighborhood structures (N1 and N2). N1 consists of moving all critical operations that belong to critical paths of jobs which affect the criterion being optimized and N2 is a subset of N1 where only operations which belong to blocks. New, efficient and fast sufficient feasibility conditions to obtain moves of the neighborhoods and evaluation functions that assess the quality of the feasible moves are proposed.

A review of the main issues that affect the livelihoods of non timber forest products (NTFP) focusing on the commercialisation issues of gatherers/producers and traders, was made for Colombia. It aimed to investigate broadly which are some of the cultural, economic, social, environmental, marketing and legislative issues that affect the outcomes for NTFP livelihoods. The sustainable rural livelihood framework was used to understand the main issues affecting NTFP livelihoods and to propose alternatives to improve the constraints found in NTFP development and commercialisation. The study identify the great importance of NTFP local and regional markets for rural development, and some data was given for international markets in order to understand the magnitude of the commerce and the possibilities that might arise for some promissory products. The review of some institutional and organisation incentives influencing NTFP production and commercialisation was undertaken by reviewing the forestry policies and some of its instruments. The study used secondary data of reports made mainly in Latin-America. The report concludes that the policies and norms that influence NTFP, such as the forestry policy and plans do not consider the importance of NTFP for social and environmental objectives. For NTFP research, the analysis of the commercialisation process is strongly co-related to social networks, ecology, cultural taboos, norms for management of NTFP and effectiveness of support organisations. NTFP livelihoods can be seriously affected by government organisations and NGO’s if they are treated as traditional commodities because of the fragility and uniqueness of their ecology, economy and social structures. The report gives some recommendations to government agencies and researchers that wish to mend the constraints found for NTFP successful development.

After more than 50 years of internal armed conflict, the peace agreement between the Colombian Government and the Revolutionary Armed Forces of Colombia- People’s Army (FARC-EP) raises both hope and concern. There are several opportunities for people, derived from wealth and land redistribution. However, the environmental sustainability of the mechanisms to implement the agreements represent the biggest challenges facing the future. Constructing future scenarios with indigenous peoples living in Forest Reserves and external agents working in La Pedrera, Amazonas Department, is a good case example to define what kind of futures they can envision. For this research project, I designed and served as facilitator during six scenario construction exercises, with 40 Forest Reserve dwellers. Additionally, I conducted six semi-structured formal interviews with relevant actors. The process of synthesising participants’ views, the current state of the territory, and perceived future opportunities and threats, lead me to a baseline and three future scenarios: Utopian, Business as Usual, and Dystopian. Furthermore, I used the capabilities approach, and Political Ecology, to understand the kinds of conflicts present in the area, to explore real possibilities of peace for the territory, and to expand the roles participants described as more conducive to achieve desirable futures.

Based on ethnographic fieldwork, this dissertation investigates borderscaping processes faced by irregular migrants and their living conditions in Madrid. It aims to study how borders/social boundaries are constructed in the city as irregular migrants move around living their lives -and how they deal to work, to live, to access to healthcare, etc. in a context of borderscapes that are present in the everyday life. This paper also attempts to determine how irregular migrants navigate the city and find ways to contest those borders. Through the case study of irregular migrants, this research examines their social interactions, their experiences with borderscapes surrounding them in different scenarios, and the tactics they implement to make use of the public space. In doing so, it sheds light on the dynamics which link their motivations and ways of getting around in a context of invisible borders. This paper highlights the practices that irregular migrants use to overcome borderscapes in an urban context of precariousness while performing different tactics trying to find a room for maneuver for negotiating their place in the city. This study aims to contribute to broadening the literature on the relation between irregular migration and its impact on multi-ethnic cities. Therefore, the research provides insights to the scholarships of borderscapes, a theoretical approach to the concept of borders as analytical entities that follow the migrant, particularly the one in an administrative irregular situation.

Face recognition is a specific case of object recognition. It has received special attention in the recent years due to a great variety of applications such as robot-human interaction, control by gesture, surveillance, security, and people tracking. The idea of face recognition is to give a computer system the ability of finding and recognizing human faces fast and precisely in images or videos. Face recognition aspires to work similar to human perception. Humans identify a big number of known faces, even after years of separation, or under extreme occlusion conditions, e.g. just by looking at a small part of a face. It is a complex task since faces can have different colors, poses, expressions, and sizes or they can be affected by illumination variations or occlusion conditions. Today, there are different methods of face recognition: feature-based approaches (low-level analysis, feature analysis, active shape models) that make explicit use of facial-features such as skin color, facial landmarks or face geometry, and image-based approaches (linear subspace models, neural networks, statistical approaches). The recent increase in the volume of data and computational resources has led to the need for fast and scalable recognition techniques. These techniques should be robust to non-rigid deformations, clutter, occlusion and illumination variations, but, at the same time, they must be sensitive to variations among faces from different persons. For these reasons, neural networks have become a surge of interest Initially, shallow regular neural networks could be used for small image sizes, but they would not scale to deeper networks since a huge amount of parameters would be necessary to be learnt, which can easily cause overfitting. As a result, Convolutional neural networks (CNNs) were proposed. In a CNN, neurons in a layer are connected to small regions of previous layers, which is different to regular neural networks, where all neurons are connected in a full manner. Besides, CNNs make correct assumptions about the nature of the images, for example locality of pixel dependencies \cite{ImageNet}. In general, CNNs have fewer connections and parameters, they are easier to train, and they present similar or better performance than the regular neural networks \cite{ImageNet}. As an extension of the CNNs, deep CNNs were introduced by Imagenet authors because a big number of high-resolution images and powerful GPUs are now available. The authors increased the number of convolutional layers, and they use large receptive fields in the first convolutional layer. As a result, overfitting, which is inherent to the large size of the model, is avoided and effective results are achieved. In addition, the authors of the VGGnet continued adding convolutional layers, but they keep the size of the receptive fields very small (3x3 convolutions) with a stride of 1, throughout the whole network, which decreases the amount of parameters.

Current research on automated vehicles focuses mainly on the drivers of automated vehicles, on its potential to improve the efficiency of traffic operations, safety, congestion and societal benefits, public’s acceptance of automated vehicles as a transport system and the willingness to buy automated vehicles. Nevertheless, there is a research gap in an equally important topic of research; the interactions of the automated vehicles with Vulnerable Road Users (VRU), i.e., cyclists and pedestrians. The WEpods (shuttle buses) are the first automated pods on public roads amidst other traffic, for an extended period of time in the province of Gelderland, in the Netherlands. The main research question revolves around the safety perception of vulnerable road users (VRUs) when interacting with automated vehicles, specifically at unsignalised intersections, and their crossing behaviour in comparison with traditional motor vehicles. The data on road users’ perception was gathered through face-to-face interviews (𝑁=22), a focus group (𝑁=8), and an online survey (𝑁=198). The results of this research showed that in terms of perceived safety, in general, VRUs (pedestrians and cyclists) feel significantly safer when sharing the road with the WEpods (max. speed of 15 𝑘𝑚/ℎ) compared to traditional motor vehicles (max. speed of 30 𝑘𝑚/ℎ). However, cyclists reported feeling less safe when interacting at unsignalised intersections with the automated vehicles, while there was not significant effect on pedestrians. Similarly, pedestrians more often opted for crossing facilities in the presence of the WEpods than in the presence of traditional motor vehicles (this can be interpreted as the result of perhaps feeling less safe), while no significant difference was reported for cyclists. Some of the reasons that could explain the trust in the WEpods are its low operational speed and the trust of most (81.1%) of the VRUs in the automated technology. This makes them expect the WEpods will stop in all possible instances, even when other traffic participants violate traffic rules. Surprisingly, a significant proportion (63.2%) of the participants was not aware of the presence of the steward on board of the WEpods. On the other hand, variables such as the awareness of the steward and having interacted with the WEpods increased the perceived safety amongst VRUs. Moreover, eye contact and gestures use as part of the actual interaction with human drivers of traditional motor vehicles particularly when crossing, was reported to be of importance by the respondents and has also been previously reported in the literature. The VRUs who said that they rely on cues given by drivers, more often indicated a preference to cross at dedicated facilities in the presence of the WEpods than those who stated not to depend on this type of communication. In order to substitute this lack of “real” interaction, information about the WEpods’ operations appeared to be desired by most of the participants in the form of visual information or a mix of auditory and visual. Finally, it was found that individual characteristics of the VRUs, such as their gender and other demographic variables could also have an impact on their perceived safety of VRUs interacting with the WEpods. The findings of the current research appear to point at a prudent attitude of cyclists and pedestrians in their interaction with automated vehicles. Nevertheless, this conservative mindset could be balanced by informing other road users about both, the features (e.g., the presence of a steward on board) and the limitations (e.g., the technology unable to respond to unexpected conditions) of the WEpods. It is considered that this information, along with a suitable communication of intentions of the vehicle to its surroundings are adequate tools to achieve a safe interaction between VRUs and automated vehicles.

Generally studies about identity and consumption have assumed that individuals are immersed in a context of abundance, in which their possibilities to fulfil their needs and desires to purposefully construct a consumption lifestyle are granted. Within this context, studies from the Consumer Culture Theory perspective have described how individuals navigate consumer culture by developing enduring relationships with possessions that help them to build identities and a sense of self. However, this is not always possible during every individual’s life. Certain situational factors not only provoke the individual’s loss of what they have already built, but also lead them to a restricted consumption context. The present study focuses on forced and uncertain changing events, those whose severity and/or rapid change disrupts an individual’s entire life. Through a phenomenological approach of the homeless experience, this study attempts to understand individuals’ transition into a restricted consumption context. The empirical data obtained from a twenty two month ethnographic study evidences that experiencing homelessness, individuals’ loss of possessions and the perceived uncertainty that characterizes life on the streets, trigger not only a self-transformation process, but also alter their relationship with the material world. The findings are contrasted with the current literature extending previous work about transition and consumption by: a) Proposing a new transformational routine to describe the forced self-transformations and how consumption (or the lack of it) becomes an element that influences the deconstruction and construction of a new self. b) Identifying how in a restricted consumption context, individuals develop a different relationship with the material world, and how this changes their modes of consumption.

In many cultures palms offer a vast number of products, especially Non-Timber-Forest Products (NTFPs), which have been traditionally used by indigenous and mestizo groups in Latin America. Some species have gone beyond the domestic use and their commercialization has reached local, national and international markets. Among the palm products that are widely commercialized in South America are palm heart (Euterpe oleracea), extracted from the young unfolded spear leaves of the palms, and the handicraft woven from fibers (Astrocaryum chambira, A. malybo and A. standleyanum), all extracted from the leaflets. In Colombia, these four palm species are economically important for the harvesting communities as well as for wholesalers and retailers. However, commercialization has been based on the extraction of raw material from wild palm stands up to the point that several palm species are threatened by developing markets for their products, and the need of income for the harvest communities and industry. The general objective of this thesis is to describe the value chains of palm products from E. oleracea, A. chambira, A. malybo and A. standleyanum in different Colombian regional markets, as well as national and international markets, and to analyze the economic importance, potentials and implications of this trade. Data on the four value chains was gathered through interviewing all actors of the value chain and revising the literature about the commercialization of these palm products. This study assesses the main actors or organizations in the commercialization chains, their specific activities, different routes to trade products, and how well the chains currently work by conducting a qualitative and quantitative value chain analysis.Major results involve particular dynamics and distributions of the profits along each value chain, as well as common aspects: the value chains are short, simple, the commercialization channels need to be strengthened, the scarcity of the raw material is a crucial constraint for the commercialization of the products. Unsustainable harvest practices are common. Moreover, the marketing potential of each group of palm products as well as promised target markets are characterized. The principal contribution of this thesis consists in shedding light on the current status of the value chains of these four palm species in Colombia, and proposing possible routes of development to strive for sustainability in each of the value chains analysed. Moreover, this study provides information about the economic importance of the palm products to the local communities and the need to upgrade the commercialization channels, products and communal incentives to assign equitable incomes along the chain.

In earlier decades, a number of authors have been looking at how commuters value the usefulness of travel time and at which point it is still considered to be a disutility to minimize. This document presents the results of a survey which was carried out on different transportation modes in Northern California. The results of this study show how the utility of travel time may change from one person to another, unveiling the latent relationship between several factors (i.e. Attitudinal factors, primary mode of transportation, age, gender, etc.) and what we consider the usefulness of travel time. This study included several considerations made from different approaches, including linear regression analysis and ordered probit models. The dependent variable was always considered to be the usefulness of travel time represented in the final survey by an ordinal variable. Moreover, the study comprised data segmentation (i.e. primary mode of transportation) which explained some conceptual differences between a pooled model and “active-passive” models. Finally, the outcome of this study shows how active travel modes (i.e. Car driving) are usually the most unattractive, for the reason that the possibility of engaging in different activities while traveling is very limited. Similarly, how the activity itself may change the perception of travel from a disutility to minimize to a transition or mostly useful time.