Home About us Contact
|
Home About us Contact | ||
|
|
||
Engineering Project (engineering + project)
Selected AbstractsStudies on seismic reduction of story-incresed buildings with friction layer and energy-dissipated devicesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 14 2003Hong-Nan Li Abstract A new type of energy-dissipated structural system for existing buildings with story-increased frames is presented and investigated in this paper. In this system the sliding-friction layer between the lowest increased floor of the outer frame structure and the roof of the original building is applied, and energy-dissipated dampers are used for the connections between the columns of the outer frame and each floor of the original building. A shaking table test is performed on the model of the system and the simplified structural model of this system is given. The theory of the non-classical damping approach is introduced to the calculation analyses and compared with test results. The results show that friction and energy-dissipated devices are very effective in reducing the seismic response and dissipating the input energy of the model structure. Finally, the design scheme and dynamic time-history analyses of an existing engineering project are investigated to illustrate the application and advantages of the given method. Copyright © 2003 John Wiley & Sons, Ltd. [source] The Anticipated Capitalisation Effect of a New Metro Line on Housing Prices,FISCAL STUDIES, Issue 2 2008Claudio A. Agostini H54; R21; R53 Abstract Housing units with closer access to public transportation enjoy a higher market value than those with similar characteristics but poorer access. This difference can be explained by the lower cost of transport to the main workplaces and shopping areas in town. For this reason, investments in public transport infrastructure, such as building a new metro line, are capitalised totally or partially into land and housing prices. This work empirically analyses the degree of capitalisation into housing prices of the benefits of the new Line 4 of the Santiago metro system, which began operating in December 2005. We focus on anticipated capitalisation into housing prices at the moment construction of Line 4 was announced and at the moment information on the basic engineering project was unveiled, identifying the location of the future stations. We use a unique database containing all home buying and selling transactions in the Greater Santiago area between December 2000 and March 2004. The results show that the average apartment price rose by between 4.2 per cent and 7.9 per cent after construction was announced and by between 3.1 per cent and 5.5 per cent after the location of the stations was identified. These increases were not distributed evenly, but depended on the distance from the apartment to the nearest station. An indirect effect of this kind of capitalization is that property tax collections will increase if property is reappraised following the price rise. This effect is not negligible in magnitude and could represent 11 to 17 per cent of investment in the new metro line. This raises and interesting discussion on how the metro network extension is financed. [source] Identification of a class of non-linear parametrically varying modelsINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 1 2003F. Previdi The aim of this paper is to propose a novel class of non-linear, possibly parameter-varying models suitable for system identification purposes. These models are given in the form of a linear fractional transformation (LFT) where the ,forward' part is represented by a conventional linear regression and the ,feedback' part is given by a non-linear dynamic map parameterized by a neural network (NN) which can take into account scheduling variables available for measurement. For this specific model structure a parameter estimation procedure has been set up, which turns out to be particularly efficient from the computational point of view. Also, it is possible to establish a connection between this model class and the well known class of local model networks (LMNs): this aspect is investigated in the paper. Finally, we have applied the proposed identification procedure to the problem of determining accurate non-linear models for knee joint dynamics in paraplegic patients, within the framework of a functional electrical stimulation (FES) rehabilitation engineering project. Copyright © 2002 John Wiley & Sons, Ltd. [source] Estimating survival and movements using both live and dead recoveries: a case study of oystercatchers confronted with habitat changeJOURNAL OF APPLIED ECOLOGY, Issue 1 2009Olivier Duriez Summary 1Animals facing partial habitat loss can try to survive in the remaining habitat or emigrate. Effects on survival and movements should be studied simultaneously since survival rates may be underestimated if emigrants are not considered, and since emigrants may experience reduced survival. 2We analysed movements and survival of adult wintering oystercatcher Haematopus ostralegus in response to the 1986,1987 partial closure of the Oosterschelde in the Dutch Delta. This reduced by one-third the tidal area of this major European wintering area for waders. 3We developed a novel variant of a multistate capture,recapture model allowing simultaneous estimation of survival and movement between sites using a mixture of data (live recaptures and dead recoveries). We used a two-step process, first estimating movements between sites followed by site-specific survival rates. 4Most birds were faithful to their ringing site. Winter survival was negatively affected by winter severity and was lowest among birds changing wintering site (i.e. moving outside of the Oosterschelde). 5During mild winters, survival rates were very high, and similar to before the closure in both changed and unchanged sectors of the Oosterschelde. However, the combined effect of habitat loss with severe winters decreased the survival of birds from changed sectors and induced emigration. 6The coastal engineering project coincided with three severe winters and high food stock, making assessment of its effects difficult. However, the habitat loss seems to have had less impact on adult survival and movements than did winter severity. 7 Synthesis and applications. Human-induced habitat change may result in population decline through costly emigration or reduced survival or reproduction of individuals that stay. Long-term monitoring of marked individuals helps to understand how populations respond to environmental change, but site-specific survival and movement rates should be integrated in the same model in order to maximize the information yield. Our modelling approach facilitates this because it allows the inclusion of recoveries from outside the study area. [source] A brief study of applications of the generalized reciprocal method and of some limitations of the methodGEOPHYSICAL PROSPECTING, Issue 5 2000Bengt Sjögren An analysis of the generalized reciprocal method (GRM), developed by Palmer for the interpretation of seismic refraction investigations, has been carried out. The aim of the present study is to evaluate the usefulness of the method for geotechnical investigations in connection with engineering projects. Practical application of the GRM is the main object of this study rather than the theoretical/mathematical aspects of the method. The studies are partly based on the models and field examples presented by Palmer. For comparison, some other refraction interpretation methods and techniques have been employed, namely the ABC method, the ABEM correction method, the mean-minus-T method and Hales' method. The comparisons showed that the results, i.e. the depths and velocities determined by Palmer, are partly incorrect due to some errors and misinterpretations when analysing the data from field examples. Due to the limitations of the GRM, some of which are mentioned here, stated by Palmer in his various publications, and other shortcomings of the method (e.g. the erasing of valuable information), the GRM must be regarded as being of limited use for detailed and accurate interpretations of refraction seismics for engineering purposes. [source] | ||||||||||