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Volume XIV |

Seismic loss estimates for buildings in Bucharest’s historic centre in case of another 1977 Vrancea earthquake

Abstract: As past seismic events showed, Bucharest (capital of Romania) can be significantly affected by another intermediate depth (or subcrustal) Vrancea earthquake. The 1940 (Mw 7.7) and 1977 (Mw 7.4) earthquakes put the number of casualties in Bucharest over 1600. Although most people and authorities are aware of the exposure, the mitigation actions are still improper and there is actually a very uncertain image of the current damage extent. The paper provides scientifically based answers, through quantitative earthquake loss estimation based on recently developed analytical methods, applied for buildings in the historic centre of Bucharest. The approach offers a relevant picture of the actual possible damage distribution after an earthquake similar to the 1977 event, in an area with heavy traffic and a high number of tourists. The Improved Displacement Coefficient Method used in this study relies on the description of structural behaviour within different limits due to specific ground motion parameters like spectral acceleration. The 358 buildings in the study area are assessed individually and specific vulnerability curves are assigned to each typology, based on height, construction year and material. The same classification as in the Near Real-Time System for Estimating the Seismic Damage in Romania is used. The results are evaluated in order to be further included in the system. In addition, an empirical loss assessment procedure reflecting the economic impact of the previously calculated situation was employed. Relevant maps for mean damage ratio and economic losses are presented and interpreted.

Volume XIV |

An object based building extraction method and classification using high resolution remote sensing data

Abstract: The increasing availability of the high spatial resolution satellite images has provided a new data source for building extraction. This paper proves the concept of object oriented classification using high-resolution satellite data (Cartosat-1 satellite data fused with IRS-1C, LISS IV data) for automatic building extraction using eCognition software. In this study, the overall accuracy of classified image is 0.94 and Kappa accuracy is 0.92. The producer accuracy for building, vegetation and shadow are 0.9745, 1.0 and 0.8999, respectively, whereas user accuracy for building, vegetation and shadow are 1.0, 0.9475 and 1.0 respectively. The classification overall accuracy is based on TTA mask (training and test area mask) and it is 0.98 and Kappa accuracy is 0.96. The producer accuracy for building, forest and shadow are 1.0, 1.0 and 0.7344, respectively and user accuracy for building, vegetation and shadow are 1.0, 0.9475 and 1.0, respectively.

Volume XIV |

Potential usage of met mast datasets for climatic parameters monitoring in Tulcea County, Romania

Abstract: In order to evaluate the potential usage of high-accuracy climatic data measured continuously in the frame of newly developed renewable energy facilities in Romania for real-time local scale monitoring of climatic parameters, we used 2 years (May 2009 – May 2011) of in-situ climatic datasets measured at 7 met masts locations in Tulcea County. Realization of detailed thematic climatic maps afforded a more focused view of the spatial distribution and of the local patterns for air temperature, relative humidity and pressure, wind speed, direction and energy in the frame of the study site. On the basis of these preliminary results, we emphasize the great potential of similar in-situ real-time measured data to be integrated in the future, together with the data provided by meteorological stations, into complex databases. Their usefulness emerges from their capabilities of being integrated in specialized web-GIS platforms for real-time or near-real-time monitoring of small spatial scale climatic parameters and of contributing to climatic models calibration, weather forecasting, feeding early warning systems for local climatic hazards or to rapid small spatial scale assessment of air pollutants dispersal following different scenarios of wind speed and direction. Further research and initiatives are necessary in the near future for the creation and implementation of these databases in order to become operational.

Volume XIV |

Biourbanism – a solution for mitigation of urban climate. Case study Bucharest city

Abstract: As a living environment or biotope of the human species, urban structures must meet not only the economic, social and political rights of the people, but also their biological and neurophysiologic requirements. A new scientific approach to urban planning is biourbanism or organic urbanism, which considers the urban environment as being a hyper-complex living thing. From the scientific point of view, this approach opens the way to new scenarios for urban planning research. The aim of the study is to promote this modern concept of urban planning for Bucharest City in the context of its climate vulnerability. The objectives of our investigation are the following: analyzing the dynamic of climate conditions of the city, highlighting the weather risks for the population and devising scenarios for implementing the concept in Bucharest. The research methodology focused on the following: the discussion of conceptual framework based on specialty literature, the calculation of bioclimatic indices in order to assess the city’s vulnerability to climate conditions and the presentation of “biourban” improvement models applicable to urban fabric samples. The study reveals the vulnerability of Bucharest City in relation to the specific risks associated to the weather phenomena of the summer season (high temperatures and moisture deficit), as argument in favour of preparing implementation scenarios for biourbanism ideas.

Volume XIV |

Considerations on the influence of micro urban heat islands to the temperature – humidity index in Craiova

Abstract: According to National Administration of Meteorology, July month of 2015, will represent one of the longest periods with canicular temperatures in the last decades. In Oltenia region and in Craiova city, too, yellow or orange code warning, had to be declared. To determine thermal discomfort sensation felt by the population of Craiova, experimental research concerning micrometeorological measurements of the real temperature and relative humidity that contribute to the local Temperature – Humidity Index (THI) value was performed. According to the experimental research results, con-firmed by using thermovision too, within Craiova, four micro urban heat islands were identified. Despite the low mean value of relative humidity, due to the temperature’s high mean value, in these hot spots the THI average was 94.93, and the thermal discomfort sensation would have made necessary special protection measures. The same air micrometeorological parameters in these four hot spots were compared with the ones recorded in English Park where due to vegetation and trees’ shadow, the THI average was 84.87, thus the thermal discomfort sensation would have made necessary adequate protection measures. The paper proposes several practical methods that would be utilized in order to decrease the pavements’ and buildings’ walls temperatures, or to increase the vegetation surfaces that contribute to the THI de-creasing in the micro urban heat islands of Craiova city.