517 research outputs found
Development of a Counter-Flow Thermal Gradient Microfluidic Device
This work presents a novel counter-flow design for thermal stabilization of microfluidic thermal reactors. In these reactors, precise control of temperature of the liquid sample is achieved by moving the liquid sample through the thermal zones established ideally through the conduction in the solid material of the device. The goal here is to establish a linear thermal distribution when there is no flow and to minimize the temperature change at flow condition. External convection as well as internal flowinduced effects influence the prescribed thermal distribution. The counter-flow thermal gradient device developed in this study is capable of both stabilizing the thermal disturbance caused by the flow as well as establishing a significantly linear distribution. A temperature ramp rate of up to 102 ºC/sec was achieved for a 30 ml/hr flow rate. This configuration removes the obstacles in the way of performing temperature sensitive biological processes such as PCR and DNA melt analysis at remarkably shorter time.
Mathematical modeling including the analytical models as well as simulations was performed for a better understanding of the transport phenomena occurring in the designed microfluidic devices. External convection impact on the uniformity and linearity of the thermal distribution and the ways for minimizing it were investigated experimentally, analytically, and numerically. Also, the dissipation of a small thermal event generated from an exothermic mixing in a continuous flow thermal sensing system was investigated, and a novel numerical model was developed for suggesting the optimum location for sensing the heat using a thermoelectric sensor
Doctor of Philosophy
dissertationControlling combined sewer overflows (CSOs) is one of the greatest urban drainage challenges in more than 700 communities in the United States. Traditional drainage design typically leads to centralized, costly and energy-intensive infrastructure solutions. Recently, however, application of decentralized techniques to reduce the costs and environmental impacts is gaining popularity. Rainwater harvesting (RWH) is a decentralized technique being used more often today, but its sustainability evaluation has been limited to a building scale, without considering hydrologic implications at the watershed scale. Therefore, the goal of this research is to study watershed-scale life cycle effects of RWH on controlling CSOs. To achieve this goal, (i) the life cycle costs (LCC) and long-term hydrologic performance are combined to evaluate the cost-effectiveness of control plans, (ii) the life cycle assessment (LCA) and hydrologic analysis were integrated into a framework to evaluate environmental sustainability of control plans, and (iii) the major sources of uncertainty in the integrated framework with relative impacts were identified and quantified, respectively. A case study of the City of Toledo, Ohio serves as the platform to investigate these approaches and to compare RWH with centralized infrastructure strategies. LCC evaluation shows that incorporating RWH into centralized control plans could noticeably improve the cost-effectiveness over the life cycle of drainage infrastructure. According to the results of the integrated framework, incorporating RWH could reduce Eco-toxicity Water (ETW) impacts, but caused an increase in the Global Warming Potential (GWP). In fact, incorporating RWH contributes to avoidance of untreated discharges into water bodies (thus reducing ETW) and additional combined sewage delivered to treatment facilities (thus increasing GWP). The uncertainty analysis suggests that rainfall data (as a hydrologic parameter) could be a significant source of the uncertainty in outputs of the integrated framework. Conversely, parameters of LCIA (life cycle impact assessment) could have trivial impacts on the outputs. This supports the need for robust hydrologic data and associated analyses to increase the reliability of LCA-based urban drainage design. In addition, results suggest that such an uncertainty analysis is capable of rendering optimal RWH system capacity as a function of annual rainfall depth to lead to minimized life cycle impacts. Capacities smaller than the optimal size would likely result in loss of RWH potable water savings and CSO control benefits, while capacities larger than optimal would probably incur excessive wastewater treatment burden and construction phase impacts
Design Of Computer Vision Systems For Optimizing The Threat Detection Accuracy
This dissertation considers computer vision (CV) systems in which a central monitoring station receives and analyzes the video streams captured and delivered wirelessly by multiple cameras. It addresses how the bandwidth can be allocated to various cameras by presenting a cross-layer solution that optimizes the overall detection or recognition accuracy. The dissertation presents and develops a real CV system and subsequently provides a detailed experimental analysis of cross-layer optimization. Other unique features of the developed solution include employing the popular HTTP streaming approach, utilizing homogeneous cameras as well as heterogeneous ones with varying capabilities and limitations, and including a new algorithm for estimating the effective medium airtime. The results show that the proposed solution significantly improves the CV accuracy.
Additionally, the dissertation features an improved neural network system for object detection. The proposed system considers inherent video characteristics and employs different motion detection and clustering algorithms to focus on the areas of importance in consecutive frames, allowing the system to dynamically and efficiently distribute the detection task among multiple deployments of object detection neural networks. Our experimental results indicate that our proposed method can enhance the mAP (mean average precision), execution time, and required data transmissions to object detection networks.
Finally, as recognizing an activity provides significant automation prospects in CV systems, the dissertation presents an efficient activity-detection recurrent neural network that utilizes fast pose/limbs estimation approaches. By combining object detection with pose estimation, the domain of activity detection is shifted from a volume of RGB (Red, Green, and Blue) pixel values to a time-series of relatively small one-dimensional arrays, thereby allowing the activity detection system to take advantage of highly capable neural networks that have been trained on large GPU clusters for thousands of hours. Consequently, capable activity detection systems with considerably fewer training sets and processing hours can be built
Treatment of the Prominent Mandibular Angle by Using a Custom Made Surgical Splint
In this case report, we would like to present an alternative surgical technique for the treatment of the bilateral prominent mandibular angles by using a custom-made resin splint (template). The prefabricated template provided a precise outline for the osteotomy, which alleviated the uncertainty of the osseous cut. Furthermore, masseter muscle myomectomy was not necessary in this case which decreased morbidity, and procedure and recovery time, while assuring a more symmetric outcome
Gestione operativa e strategica di un progetto di ricerca mediante la componente Project System di mySAP ERP
La presente tesi si pone lo scopo di illustrare la gestione operativa e strategica di un progetto di ricerca mediante la componente Project System di mySAP ERP.
La tesi è strutturata in quattro capitoli.
Nel primo capitolo è descritta la situazione attuale della ricerca in Italia, quali sono gli strumenti, le attività , i luoghi e gli attori; sono esaminate le politiche europee, nazionali e regionali di ricerca e descritti i sistemi di valutazione e di finanziamento della ricerca.
Nel secondo capitolo è esposta la soluzione Project System di mySAP ERP, uno strumento che permette un miglior monitoraggio del progetto e consente di effettuare analisi sullo stato di avanzamento del progetto, soprattutto dal punto di vista tempi e costi. È un sistema che permette di mantenere le caratteristiche di flessibilità e snellezza, guadagnando però un maggior rigore nella gestione del processo ed assicurandosi qualità e tempestività delle informazioni.
Nel terzo capitolo è descritto l’EuBorderConf, sigla che indica "L'Unione Europea ed i conflitti di confine: l'impatto dell’integrazione ed associazione", che è un progetto finanziato nell'ambito del Quinto Programma Quadro dell'Unione Europea. Il progetto tenta di capire se e come l'UE, tramite integrazione e associazione, possa essere d'aiuto nel trasformare la natura dei confini da linee di conflitto a linee di cooperazione.
Il quarto capitolo espone l’implementazione del progetto di ricerca EuBorderConf mediante l’applicazione Project System di mySAP ERP.
Infine, si presentano le conclusioni ed i possibili sviluppi futuri sulla tesi svolta e sul tipo di esperienza maturata durante il lavoro svolto in azienda nel periodo di stesura della tesi
- …