75,750 research outputs found

    The Community – Based Flood Disaster Risk Reduction (CBDRR) in Beringin Watershed in Semarang City

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    Population growth in Semarang city is certainly increasing land demand for settlement. Limited land and weak regulation enforcement of land control trigger the land use change including the watershed area. Semarang City Spatial Plan 2011-2031 has determined Beringin as a buffer area with limited physical development allocation but the citizens utilized the watershed area for settlement. Settlement developments in the area reduce the watershed ability to catch water and river capacity due to increased sedimentation. These two reasons are the main cause of the flash flood disaster (regularly in rainy season) in seven villages of Beringin watershed. The condition is exacerbated by the tidal flood occurred in two village lies in coastal. In 2012, Semarang City government developed Flood Forecasting and Warning System as one of Climate Change Adaptation Measures known as Flood Early Warning System (FEWS). One of important output of FEWS is community-based disaster risk reduction. Community participation process in the FEWS has made it possible for the community to identify disaster risk characteristics, to propose solution for reducing flood risk which is suitable to the local wisdom, to increase the community capacity and to organize one of themselves in a disaster preparedness group which run quite independently

    A research study on Hong Kong's building services engineering profession: a review of the building services engineering profession in the United Kingdom

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    A review of the building services engineering profession in the United Kingdom is considered in this document. It provides supporting information for a comprehensive study into the profession in Hong Kong which is being conducted by Hong Kong Polytechnic University on behalf of the Hong Kong Institution of Engineers. The overall aim of the work is to investigate mechanisms for raising the profile of building services engineers in Hong Kong

    Investigating use of space of pedestrians

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    Understanding use of space of pedestrian is important to plan/design street environments or large public transport facilities. The purpose of a series of our research is to investigate use of space of various pedestrians in a variety of environmental situations. The research is a part of PAMELA project designed to test existing and proposed pedestrian environments and street facilities (i.e. a bus stop) under controlled conditions. This paper is aimed at setting out the background of the research, and presenting a basic frame work for subsequent research. Strength of our approach is the microscopic heterogeneous approach, where each walking person is regarded different from others. Relations among characteristics of pedestrians, characteristics of facilities/ environments, and resulting actions of pedestrians are carefully examined. Conclusion suggests directions of further research

    Towards the Holy Grail: combining system dynamics and discrete-event simulation in healthcare

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    The idea of combining discrete-event simulation and system dynamics has been a topic of debate in theoperations research community for over a decade. Many authors have considered the potential benefits ofsuch an approach from a methodological or practical standpoint. However, despite numerous examples ofmodels with both discrete and continuous parameters in the computer science and engineering literature,nobody in the OR field has yet succeeded in developing a genuinely hybrid approach which truly integratesthe philosophical approach and technical merits of both DES and SD in a single model. In this paperwe consider some of the reasons for this and describe two practical healthcare examples of combinedDES/SD models, which nevertheless fall short of the “holy grail” which has been so widely discussed inthe literature over the past decade

    Modeling the growth of multicellular cancer spheroids in a\ud bioengineered 3D microenvironment and their treatment with an\ud anti-cancer drug

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    A critical step in the dissemination of ovarian cancer cells is the formation of multicellular spheroids from cells shed from the primary tumor. The objectives of this study were to establish and validate bioengineered three-dimensional (3D) microenvironments for culturing ovarian cancer cells in vitro and simultaneously to develop computational models describing the growth of multicellular spheroids in these bioengineered matrices. Cancer cells derived from human epithelial ovarian carcinoma were embedded within biomimetic hydrogels of varying stiffness and cultured for up to 4 weeks. Immunohistochemistry was used to quantify the dependence of cell proliferation and apoptosis on matrix stiffness, long-term culture and treatment with the anti-cancer drug paclitaxel.\ud \ud Two computational models were developed. In the first model, each spheroid was treated as an incompressible porous medium, whereas in the second model the concept of morphoelasticity was used to incorporate details about internal stresses and strains. Each model was formulated as a free boundary problem. Functional forms for cell proliferation and apoptosis motivated by the experimental work were applied and the predictions of both models compared with the output from the experiments. Both models simulated how the growth of cancer spheroids was influenced by mechanical and biochemical stimuli including matrix stiffness, culture time and treatment with paclitaxel. Our mathematical models provide new perspectives on previous experimental results and have informed the design of new 3D studies of multicellular cancer spheroids

    Modelling the positioning of single needle electrodes for the treatment of breast cancer in a clinical case

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    Background: Breast cancer is the most common cancer in women worldwide and is the second most common cause of cancer death in women. Electrochemotherapy (ECT) used in early-phase clinical trials for the treatment of primary breast cancer resulted in a not complete tumor necrosis in most cases. The present study was undertaken to analyze the feasibility to use ECT to treat patients with histologically proven unifocal ductal breast cancer. In particular, results of ECT treatment in a clinical case are compared with the ones of a simplified 3D dosimetric model. Methods: This clinical study was conducted with the pulse generator Cliniporator Vitae (IGEA, Carpi, Italy). ECT procedures were performed according to ESOPE standard operating procedures. Five single needle electrodes were used with one positioned in the center of the tumor, and the other four distributed around the nodule. Histological images of the resected tumor are compared with the maps of the electric field obtained with a simplified 3D model in Comsol Multiphysics v 4.3. Results: The results of the clinical case demonstrated a reduced efficacy of the ECT treatment described. The proposed simple numerical model of the breast tumor located in a low conductive tissue suggests that this is due to the reduced electric field induced inside the tumor with such 5 electrodes placement. However, where the electric field is predicted higher than the reversible electroporation threshold (E > 400 V/cm), also the histological images confirm the necrosis of the target with a good agreement between the modeled and clinical results. Conclusions: The results suggest the dependence of the effectiveness of the treatment on the careful placement of the electrodes. A detailed planned procedure for the tumor analysis after the treatment is also needed in order to better correlate the single electrode positions and the histological images. Simulation models could be used to identify better electrodes configuration in planning the experimental protocol for ECT treatment of breast tumors
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