• Structural Engineering and Mechanics
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• v.59 no.4
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• pp.703-718
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• 2016

Masonry arch bridges present a large segment of Iranian railway bridge stock. The ever increasing trend in traffic requires constant health monitoring of such structures to determine their load carrying capacity and life expectancy. In this respect, the performance of one of the oldest masonry arch bridges of Iranian railway network is assessed through field tests. Having a total of 11 sensors mounted on the bridge, dynamic tests are carried out on the bridge to study the response of bridge to test train, which is consist of two 6-axle locomotives and two 4-axle freight wagons. Finite element model of the bridge is developed and calibrated by comparing experimental and analytical mid-span deflection, and verified by comparing experimental and analytical natural frequencies. Analytical model is then used to assess the possibility of increasing the allowable axle load of the bridge to 25 tons. Fatigue life expectancy of the bridge is also assessed in permissible limit state. Results of F.E. model suggest an adequacy factor of 3.57 for an axle load of 25 tons. Remaining fatigue life of Veresk is also calculated and shown that a 0.2% decrease will be experienced, if the axle load is increased from 20 tons to 25 tons.

• Journal of Forest and Environmental Science
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• v.30 no.3
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• pp.293-300
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• 2014

An explanatory survey was conducted to assess the contribution of palm species in carbon sequestration in the homegarden of the Sylhet Metropolitan City Corporation of Bangladesh. Assessment was done by means of two stage random sampling. A total of 10 housing area were selected randomly for the study and 4 common palm tree species were found abundantly. From the observations abundance of palm trees [Areca catechu (175/housing area), Cocos nucifera (145/housing area), Borassus flabellifer (124/housing area) and Phoenix sylvestris (27/housing area)] were found higher in all homesteads in comparison with other species. Study revealed that total organic carbon (MTOC mt/ha) was highest in Cocos nucifera (12.48 mt/ha), followed by Areca catechu (4.20 mt/ha), Borassus flabellifer (3.02 mt/ha) and Phoenix sylvestris (0.59 mt/ha). Total amount of organic carbon stored by palm trees in homestead areas was found 20.28 metric ton/ hector in the study area. Study revealed that palm trees of homestead forest accumulate a good amount of biomass and is a good sinker of organic carbon from the atmosphere. Proper management of palm trees will help to improve the local, national and international community through carbon sequestration.

• Earthquakes and Structures
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• v.4 no.3
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• pp.299-324
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• 2013

The current research focuses on the seismic vulnerability assessment of typical Southern Europe buildings, based on processing of a large set of observational damage data. The presented study constitutes a sequel of a previous research. The damage statistics have been enriched and a wider damage database (178578 buildings) is created compared to the one of the first presented paper (73468 buildings) with Damage Probability Matrices (DPMs) after the elaboration of the results from post-earthquake surveys carried out in the area struck by the 7-9-1999 near field Athens earthquake. The dataset comprises buildings which developed damage in several degree, type and extent. Two different parameters are estimated for the description of the seismic demand. After the classification of damaged buildings into structural types they are further categorized according to the level of damage and macroseismic intensity. The relative and the cumulative frequencies of the different damage states, for each structural type and each intensity level, are computed and presented, in terms of damage ratio. Damage Probability Matrices (DPMs) are obtained for typical structural types and they are compared to existing matrices derived from regions with similar building stock and soil conditions. A procedure is presented for the classification of those buildings which initially could not be discriminated into structural types due to restricted information and hence they had been disregarded. New proportional DPMs are developed and a correlation analysis is fulfilled with the existing vulnerability relations.

• Earthquakes and Structures
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• v.13 no.3
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• pp.323-335
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• 2017

A simplified framework for the probabilistic estimation of economic losses induced by the structural vulnerability in single-story and single-bay precast industrial buildings is presented. The simplifications introduced in the framework are oriented to the definition of an expeditious procedure adoptable by government agencies and insurance companies for preliminary risk assessment. The economic losses are evaluated considering seismic hazard, structural response, damage resulting from the structural vulnerability and only structural-vulnerability-induced e]conomic losses, i.e., structural repair or reconstruction costs (stock and flow costs) and content losses induced by structural collapse. The uncertainties associated with each step are accounted for via Monte Carlo simulations. The estimation results in a probabilistic description of the seismic risk of portal-like industrial buildings, expressed in terms of economic losses for each occurrence (i.e., seismic event) that owners (i.e., insured) and stakeholders can use to make risk management decisions. The outcome may also be useful for the definition of the insurance premiums and the evaluation of the risks and costs for the owner corresponding to the insurance industrial costs. A prototype of a precast concrete industrial building located in Mirandola, Italy, hit by the 2012 Emilia earthquake, is used as an example of the application of the procedure.

• Journal of Navigation and Port Research
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• v.36 no.9
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• pp.741-751
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• 2012

This article analyzes the interdependency between nonrenewable marine sand resources and renewable fishery resources by the developed dynamic bioeconomic model. The developed bioeconomic model is applied to a case study of efficient sustainable management for marine sand mining, which adversely affects a valuable blue crab fishery and its habitat in Korea. The socially-efficient extraction plan for marine sand and the time-variant environmental external costs to society in terms of diminished harvest rate of blue crab are determined. To take into account long-term effects from destroyed fishery habitat, a Beverton-Holt age structure model is integrated into the bioeconomic model. The illustrative results reveal that the efficient sand extraction plan is dynamically constrained by the stock size of the blue crab fishery over time. Thus, the dynamic environmental external cost is more realistic resource policy option than the classical fixed external cost for determining socially optimal extraction plans. Additionally, the economic value of bottom habitat, which supports the on- and off-site commercial blue crab fishery is estimated. The empirical results are interpreted with emphasis on guidelines for management policy for marine sand mining.

• Land and Housing Review
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• v.5 no.3
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• pp.131-136
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• 2014

The Hong Kong Housing Authority (HKHA) develops and implements a public housing programme to meet the housing needs of people who cannot afford private rental housing. The HKHA has an existing stock of about 740,000 public rental flats (PRH). According to the 2014 Policy Address, the Government aims to provide an average of about 20,000 PRH units and about 8,000 Home Ownership Scheme (HOS) units per year. We care for the environment. In developing new housing estates, we conduct thorough environmental studies such as microclimate studies and air ventilation assessment, and use passive design to harness the natural characteristics of our sites. We employ environment-friendly design and construction methods, using modular flat design, pre-cast and pre-fabricated construction techniques as well as recycled, green construction materials. We conduct Carbon Emission Estimation for all our projects, conserve the use of natural resources and reduce wastes throughout the life cycle of buildings. We care for people. We adopt the principles of Universal Design and Barrier Free Access for the convenience and welfare of people of all ages and abilities. We carry out Community Engagement to collect stakeholders' views and aspirations, and incorporate them in the design of our projects. We also carry out surveys of residents' views after the occupation of new estates to gauge our success and identify areas for improvement.

• Information Systems Review
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• v.3 no.1
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• pp.19-30
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• 2001

With the e-business paradigm emerging, the website became a critical resource for most corporations. However, the amount of value creation through internet is still in question. This paper shows the result of an exploratory study on website assessment, following the tradition of Technology Acceptance Model (TAM). We viewed the intended usage as the value of the website and added such factors as playfulness, commitment, system quality, and information security as external variables of the model. Website types, visiting purposes, and the user system quality were included as moderators. The website value could differ depending on website types, purposes of the use and system quality. In the case of internet shopping malls, playfulness, compatibility, website quality were identified as key influencers, while for stock trading users, however, commitment and security factors are more important. In terms of user purposes, information search requires both the compatibility and the website quality. Also the website quality was strongly affected by the user system quality. In other words, any investment of upgrading the website system quality can be meaningless unless the user system quality is improved as well. For each variable considered, empirical results are discussed and practical implications are provided.

• Wind and Structures
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• v.29 no.3
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• pp.177-194
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• 2019

While establishing adequate load paths in the light-frame wood structures is critical to maintain the overall structural integrity and avoid significant damage under extreme wind events, the understanding of the load paths is limited by the high redundant nature of this building type. The objective of the current study is to evaluate the system effects and investigate the load paths in the wood structures especially the older buildings for a better performance assessment of the existing building stock under high winds, which will provide guidance for building constructions in the future. This is done by developing building models with configurations that are suspicious to induce failure per post damage reconnaissance. The effect of each configuration to the structural integrity is evaluated by the first failure wind speed, amajor indicator beyond the linear to the nonlinear range. A 3D finite-element (FE) building model is adopted as a control case that is modeled using a validated methodology in a highly-detailed fashion where the nonlinearity of connections is explicitly simulated. This model is then altered systematically to analyze the effects of configuration variations in the model such as the gable end sheathing continuity and the gable end truss stiffness, etc. The resolution of the wind loads from scaled wind tunnel tests is also discussed by comparing the effects to wind loads derived from large-scale wind tests.

• Journal of Information Science Theory and Practice
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• v.11 no.2
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• pp.37-66
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• 2023

Scientometrics and research evaluation describe and analyze research publications when conducting publication, citation, and topic analyses. However, what exactly is a (scientific, academic, scholarly or research) publication? This article demonstrates that there are many problems when it comes to looking in detail at quantitative publication analyses, citation analyses, altmetric analyses, and topic analyses. When is a document a publication and when is it not? We discuss authorship and contribution, formally and informally published documents, as well as documents in between (preprints, research data) and the characteristics of references, citations, and topics. What is a research publication? Is there a commonly accepted criterion for distinguishing between research and non-research? How complete and unbiased are data sources for research publications and sources for altmetrics? What is one research publication? What is the unit of a publication that causes us to count it as "1?" In this regard, we report problems related to multi-author publications and their counting, weighted document types, the unit and weighting of citations and references, the unit of topics, and counting problems-not only at the article and individual researcher level (micro-level), but also at the meso-level (e.g., institutions) and macro-level (e.g., countries). Our results suggest that scientometric counting units are not reliable and clear. Many scientometric and research evaluation studies must therefore be used with the utmost caution.

• Geomechanics and Engineering
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• v.37 no.6
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• pp.565-576
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• 2024

In this study, the earthquake risk assessment of single-story RC precast buildings in Turkey was carried out using loss curves. In this regard, Kocaeli, a seismically active city in the Marmara region, and this building class, which is preferred intensively, were considered. Quality and period parameters were defined based on structural and geometric properties. Depending on these parameters, nine main sub-classes were defined to represent the building stock in the region. First, considering the mean fragility curves and four different central damage ratio models, vulnerability curves for each sub-class were computed as a function of spectral acceleration. Then, probabilistic seismic hazard analyses were performed for stiff and soft soil conditions for different earthquake probabilities of exceedance in 50 years. In the last step, 90 loss curves were derived based on vulnerability and hazard results. Within the scope of the study, the comparative parametric evaluations for three different earthquake intensity levels showed that the structural damage ratio values for nine sub-classes changed significantly. In addition, the quality parameter was found to be more effective on a structure's damage state than the period parameter. It is evident that since loss curves allow direct loss ratio calculation for any hazard level without needing seismic hazard and damage analysis, they are considered essential tools in rapid earthquake risk estimation and mitigation initiatives.