Community dance and youth empowerment in Uganda

This study documented the ideologies and strategies used by community dance organization to empower youth and revealed youth experience in such project. The whole research employed a qualitative approach. The Breakdance Project Uganda (BPU), which had provided free breakdance classes to disfranchised youth for more than 10 years, was selected as the study case. Thirteen youth aged from 15-30 who had been participated in BPU for more than 1 year were recruited in in-depth interviews and focus group discussions using a purposive sampling approach, one BPU facilitator was interviewed about the strategies and ideologies of the project. Recordings of interviews and focus group were transcribed in a denaturalized way and analyzed in a thematic approach. The participant observation note also worked to compensate the data of the research. In general, the study revealed that community dance project had a positive impact on lives of youth, especially those who had stayed longer. Dancing as an expressive performing art improved their self-esteem. The dance community provided a safe and resourceful place for youth to explore and develop themselves. Thus community dance project provided chance for youth to be empowered socially and economically. Besides the youth also gained potent sense of self, developed more skills and competences, and raised critical awareness about themselves and the environment. Eventually youth were more able to control over their lives. However there were also challenges in terms of time and transportation expense for youth to attend the dance session, also there could be sub-groups in such project that brought negative impact on youth. Moreover the society especially parents usually held negative image of such dance group thus stopped their children from participation

CadiBack: Extracting Backbones with CaDiCaL

The backbone of a satisfiable formula is the set of literals that are true in all its satisfying assignments. Backbone computation can improve a wide range of SAT-based applications, such as verification, fault localization and product configuration. In this tool paper, we introduce a new backbone extraction tool called CadiBack. It takes advantage of unique features available in our state-of-the-art SAT solver CaDiCaL including transparent inprocessing and single clause assumptions, which have not been evaluated in this context before. In addition, CaDiCaL is enhanced with an improved algorithm to support model rotation by utilizing watched literal data structures. In our comprehensive experiments with a large number of benchmarks, CadiBack solves 60% more instances than the state-of-the-art backbone extraction tool MiniBones. Our tool is thoroughly tested with fuzzing, internal correctness checking and cross-checking on a large benchmark set. It is publicly available as open source, well documented and easy to extend

Toxicity Assessment of PAHs and Metals to Bacteria and the Roles of Soil Bacteria in Phytoremediation of Petroleum Hydrocarbons

Petroleum hydrocarbons (PHCs) are a class of ubiquitous contaminants in the environment. PHCs impact to soil and water occur at well sites, refineries, service stations, and other facilities. Petroleum processing and consumption of petroleum products lead to the further release of other PHC pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) as well as metals. PHCs are causing serious environmental problems due to their widespread use. Hence, the central theme of this thesis addresses hydrocarbon pollutants and co-contaminating metals: their occurrence in environment, their mechanism of toxicity and their remediation via biological processes. This thesis is divided into two parts including seven chapters. The first part includes chapters 2, 3 and 4. Using bioluminescent bacterium Vibrio fischeri, a widely used bioindacator in environmental toxicology, the individual and mixture toxicities of phenanthrenequinone (PHQ), an oxyPAH, combined with copper and cadmium were assessed. PHQ is a main photoproduct of phenanthrene (PHE), a dominant PAH in the environment. Results showed that PHQ is much more toxic than its parent PAH. PHQ, alone or as mixtures with Cu and Cd, damages bacterial cells via enhancing production of reactive oxygen species (ROS). The mixture toxicity of Cu/PHQ was found to be dependent on the ratio of each chemical in the mixture. Two up-regulated genes, protein translocase subunit SecY gene and putative polysaccharide export protein YccZ precursor, were identified to be possibly response to PHQ exposure. Both genes are related to the detoxification of ROS. The second part of this thesis includes chapters 5, 6, and 7. Culture-dependent and -independent approaches were employed to evaluate the roles of bacteria as biodegraders or/and plant growth promoters during phytoremediation at a petroleum land farm (PLF) with a PHC concentration of ~130 g Kg-1. A plant growth promoting rhizobacteria (PGPR) enhanced phytoremediation system (PEP) was applied to remediate PLF soil. PEP promotes plant growth to establish dense vegetative cover. Results of both culturing and molecular methods showed that the enhanced populations and activities of soil microbes due to vigorous plant growth is a key factor in the success of PEP. Introduced PGPR could quickly establish significant populations by utilizing root exudates and dominate the PGPR population on seed coat and root surfaces at the early seedling stage of plant development, and thus modestly affected bacterial community structures at this time; thereafter, with plant growth, the effect of seed treatment on soil microbial community was masked by enhanced indigeneous microbial population. Therefore, the introduced PGPR did not exert significant influence on the indigenous microbial ecosystem. It does dramatically improve plant growth and PHC remediation. Thus, the PEP should be considered as an environmentally safe and effective approach for removing PHCs from impacted soils

Impinging Jet Flow and Hydraulic Jump of Newtonian and Viscoplastic Liquids

The steady laminar incompressible flow of an axisymmetric impinging jet of either a Newtonian fluid or a viscoplastic fluid of the Heschel-Bulkley type and the hydraulic jump of either a circular or polygonal shape on a solid disk is analyzed. The polygonal jump is induced by azimuthal dependence edge conditions: a non-circular disk or a circular disk with a variable edge film thickness. The thin-film and Kármán–Pohlhausen approaches are utilized as theoretical tools. To cross the jump smoothly, a composite mean-field thin-film approach is proposed. The stress singularity for a film freely draining at the disk edge is found to be equivalent to an infinite film slope. The flow in the supercritical region is insensitive to the gravity strength, but is greatly affected by the viscosity. The existence of the jump is not necessarily commensurate with the presence of recirculation. The disk size is found to can affect the film thickness in the subcritical region, vortex size and jump length significantly. The jump is relatively steeper with a stronger recirculation zone for a higher obstacle. Scaling laws for the jump properties, such as the jump radius and length, and edge film thickness, are proposed. The surface scaling separating the regions of existence/non-existence of the recirculation is found through numerical results. The non-circular jump originated from the disk non-circularity or periodic edge film thickness is found. The balance of mass and momentum is established in the radial and azimuthal directions. The geometry of a non-circular disk has little influence on the jump shape. A small azimuthal variation in the edge thickness for a circular disk leads to a significant loss of axial symmetry. An increase in the number of peaks and valleys appears as the disk radius decreases. The viscoplastic jump is found to occur closer to impingement, with growing height, as the yield stress increases; the subcritical region becomes invaded by the pseudo-plug layer. The viscosity does not influence sensibly the jump location and height except for small yield stress; only the yielded layer is found to remain sensitive to the power-law rheology for any yield stress

Democratizing Chatbot Debugging: A Computational Framework for Evaluating and Explaining Inappropriate Chatbot Responses

Evaluating and understanding the inappropriateness of chatbot behaviors can be challenging, particularly for chatbot designers without technical backgrounds. To democratize the debugging process of chatbot misbehaviors for non-technical designers, we propose a framework that leverages dialogue act (DA) modeling to automate the evaluation and explanation of chatbot response inappropriateness. The framework first produces characterizations of context-aware DAs based on discourse analysis theory and real-world human-chatbot transcripts. It then automatically extracts features to identify the appropriateness level of a response and can explain the causes of the inappropriate response by examining the DA mismatch between the response and its conversational context. Using interview chatbots as a testbed, our framework achieves comparable classification accuracy with higher explainability and fewer computational resources than the deep learning baseline, making it the first step in utilizing DAs for chatbot response appropriateness evaluation and explanation.Comment: 7 pages, 4 figures, accepted to CUI 2023 poster trac

Exemplar-AMMs: Recognizing Crowd Movements From Pedestrian Trajectories

In this paper, we present a novel method to recognize the types of crowd movement from crowd trajectories using agent-based motion models (AMMs). Our idea is to apply a number of AMMs, referred to as exemplar-AMMs, to describe the crowd movement. Specifically, we propose an optimization framework that filters out the unknown noise in the crowd trajectories and measures their similarity to the exemplar-AMMs to produce a crowd motion feature. We then address our real-world crowd movement recognition problem as a multi-label classification problem. Our experiments show that the proposed feature outperforms the state-of-the-art methods in recognizing both simulated and real-world crowd movements from their trajectories. Finally, we have created a synthetic dataset, SynCrowd, which contains 2D crowd trajectories in various scenarios, generated by various crowd simulators. This dataset can serve as a training set or benchmark for crowd analysis work

Design of a portable low-power wearable heart rate and blood oxygen monitoring system

Heart rate, blood oxygen and body temperature are all important physiological information of human body, and designing a small and portable system measurement device will have a large social and clinical economic benefit. An attempt was made to design a portable monitoring device with STM32F103C8T6 as the controller. The heart rate, blood oxygen and body temperature data are collected by MAX30102 and GYMCU90615 modules and the data are sent to an Android smart phone via Bluetooth module for analysis and display, realizing an Android-based heart rate, blood oxygen and body temperature monitoring system. The system has been tested and verified to be stable and reliable