A Regional Classification-Based Framework for Building Stock Forecasting in China’s Mainland for Seismic Risk Assessment

The flood of economic information from China in recent years has permitted reassessment of the "Chinese model of development" and the extent to which China's own development experience has conformed to it. The prevailing consensus of the 1970s concerning the substance of the model itself-typically characterized in terms of the Chinese leadership's objectives and priorities and its strategy for pursuing them-has stood up quite well. The same cannot be said about past appraisals of the extent to which China's economic reality has been reshaped to accord with the model's prescriptions. One of the most widely remarked elements of the Chinese model is the high priority assigned to regional objectives and, more specifically, to "balance" in the distribution of productive capacity and equity in the distribution of income and, hence, consumption. During the Maoist era (i.e., prior to 1979), the central government pursued regional objectives through such measures as interregional transfers of investment resources (effected via the planning system), subsidization of health and education expenditures in poor regions, and attempts to maintain a safety net of state relief (effected largely via control of grain surpluses). In short, there is little doubt that prior to 1979 the Chinese leadership placed an unusually high value on the spread of modern growth and the improvements in welfare associated with it and persistently acted to limit the emergence or widening of interregional disparities.' Although China's post-Mao leaders have shown greater concern with efficiency and with the potential trade-offs between efficiency and such goals as balance and equity, their continuation of many redistributive policies indicates that they have not abandoned regional objectives. But how successful has China been in achieving these objectives?

Since the reform and opening policy carried out in the 1980s, and after China joined the WTO, foreign trade becomes an important part of China’s national income. Some regions have gained great benefits from foreign trade and developed in a dramatic speed while many other regions have not caught up with the high speed of development. The present work investigates whether (and how) the development of foreign trade in China is related to the ever-increasing economic disparity across different regions. After discussing the evolutions of regional economic disparity and regional foreign trade in China, this paper, by using a linear regression method, attempts to investigate the relationship between regional foreign trade disparity and regional income disparity. Our regression results show that there exists a positive relationship between the two.

Regional development problems in China have been focused on by many analysts and policy makers. From the viewpoint of regional development policy, it is highly important to consider the spatial interactions among different regions. Most of the approaches have focused on certain specific regions, without taking into account interregional interdependency. The aim of this book is to analyze regional development in China from the viewpoint of spatial interaction by using inter-regional input-output model for China

This paper describes a new concept to automatically characterize building types in urban areas based on publicly available image databases, making parts of seismic risk assessment more time and cost-effective, and improving the reliability of seismic risk assessment, especially in regions where building stock information is currently not documented. One of the main steps in evaluating potential human and economic losses in a seismic risk assessment, is the development of inventory databases for existing building stocks in terms of load-resisting structural systems and material characteristics (building typologies classification). The common approach for building stock model classification is to perform extensive fieldwork and walk-down surveys in representative areas of a city, and in some cases using random sample surveys of geounits. This procedure is time and cost consuming, and subject to personal interpretation: to mitigate these costs, we have introduced a machine learning methodology to automate this classification based on publicly available image databases. We here use a Convolutional Neural Network (CNN) to automatically identify the different building typologies in the city of Oslo, Norway, based on facade images taken fromin-situfieldwork and from Google Street View. We use transfer learning of state-of-the-art pretrained CNNs to predict the Model Building Typology. The present article attempts to categorize Oslo’s building stock in five main building typologies: timber, unreinforced masonry, reinforced concrete, composite (steel-reinforced concrete) and steel. This method results in 89% accuracy score for timber buildings, though only 35% success score for steel-reinforced concrete buildings. We here classify and define for the first time a relevant set of five typologies for the Norwegian building typologies as observed in Oslo and applicable at national level. In addition, this study shows that CNNs can significantly contribute in terms of developing a cost-effective building stock model.

PurposeThe purpose of this paper is to investigate determinants of regional disparities in China's agricultural labor productivity growth.Design/methodology/approachThis paper first decomposes the regional disparity in China's agricultural productivity growth into its components: technical change, efficiency change and input accumulation per worker. The convergence test is also used to analyze the determinants of regional disparity.FindingsThe paper finds that during 1987 and 2005, although the growth of China's agricultural labor productivity mainly depended on the accumulation of inputs, technical changes contributed more to regional disparities in agricultural productivity growth.Originality/valueThis paper, which studies the determinants of regional disparities in China's agricultural labor productivity growth, contributes to a better understanding of China's agricultural growth and how to reduce the regional inequality. It is indicated that improving efficiency to promote total factor productivity growth is important for agricultural labor productivity growth for the three regions – Eastern, Central and Western – of China. The increase in inputs for Western China, and the improvement in technical change for Central and Western China are significant aspects to promote the growth of agricultural productivity and narrow the gap with Eastern China.

A Rapid Seismic Risk Assessment Method for Existing Building Stock in Urban Areas

Seismic risk in the form of impending disaster has been seen from past records that moderate-to-large earthquakes have caused the loss of life and property in all parts of Nepal. Despite the availability of new data, and methodological improvements, the available seismic hazard map of Nepal is about two decades old. So an updated seismic hazard model at the country level is imperative and logical. The seismic hazard and risk model constitute important tools for framing public policies toward land-use planning, building regulations, insurance, and emergency preparedness. In fact, the reliable estimation of seismic hazard and risk eventually minimizes social and economic disruption caused by earthquakes. In this frame of reference, the seismic risk assessment at a country level is elementary in reducing potential losses stemming from future earthquakes. Thus, this study investigates structural vulnerability, seismic risk, and the resulting possible economic losses owing to future earthquakes in Nepal. To this end, seismic risk assessment in Nepal is done using an existing probabilistic seismic hazard, a newly developed structural vulnerability, and recently released exposure data. The OpenQuake-engine, the open-source platform for seismic hazard and risk assessment from the Global Earthquake Model initiative, was used to calculate the seismic hazard and risk in Nepal. The seismic hazard and mean economic loss map were formulated for the 1, 2, 5, and 10 % probability of exceedance in 50 years. Finally, the distribution of building damage and corresponding economic losses due to the recurrence of the historical 1934 earthquake was presented in this study.

The assessment of the vulnerability of the building stock of an urban center is an essential prerequisite to its seismic risk assessment. The other two ingredients are the expected hazard over given return periods and the distribution and values of the assets constituting the building stock. All three elements of the seismic risk assessment are affected by uncertainties of aleatory nature, related to the spatial variability of the parameters involved in the assessment, and epistemic nature, related to the limited capacity of the models used to capture all aspects of the seismic behavior of buildings and to describe them in simple terms, suitable for this type of analysis. Hence it should always be kept in mind that the computation of a risk level is highly probabilistic and that to accurately represent the risk, the expected values should always be accompanied by a measure of the associated dispersion. A very preliminary estimate of the seismic capacity of the local building stock can be obtained by consulting requirements included in seismic standards and code of practices in force at the time of construction of such buildings. This information together with a temporal and spatial record of the growth of the urban center can provide a definition of classes of buildings assumed to have different capacities. This information can be obtained by looking at past and present cadastral maps with ages of buildings and knowing the historical development and enforcement of codes at the site. In general however for a correct assessment of the seismic risk, a more detailed inventory and classification should be considered, the extent of which is a function of the economic and technical resources available and of the dimensions and building density of the area under investigation, as well as the diversity within the building stock. Seismic vulnerability analysis of masonry structures has traditionally been carried out using “empirical” (or statistical) methods. These can be divided in categorization methods, which classify buildings into typologies characterized by propensity to damage, or inspection and rating methods, wherein scores are attributed to each significant characteristic of the buildings thought to have a bearing on its overall vulnerability (UNDP/UNIDO 1985). Several of these methods have been developed in the past 30 years, and the more robust and commonly used are reviewed in section “Empirical Methods.” Recent dramatic increase in computational powers and consequent improvement and refinement in numerical modelling of relatively complex structures, using either static or dynamic approaches (e.g., Fajfar and Gaspersic 1996; Vamvatsikos and Cornell 2005), has facilitated greater exploitation of analytical approaches for vulnerability assessment purposes. Analytical methods need experimental validation of the various parameters used to define the vulnerability, and so far relatively little experimental work on the behavior of masonry structures has been undertaken by the international community, albeit a wide variety of existing unreinforced masonry typologies, both historic and modern, exists. The framework within which analytical methods can be applied and their limitation are presented in section “Analytical Methods.”

Regional disparities in China have recently attracted the attention of economists both inside and outside China. In particular, researchers and policy makers are concerned with how economic reforms have affected regional disparities in China. As a result, there has been a boom in the literature. However, the exploding literature has so far presented conflicting results. The aim of this paper is to review the literature in this field and to present new evidence on income disparities in China’s regional economies. This study is based on the application of regional GDP figures covering the period of 1953‐1997. It attempts to assess and consolidate the findings from previous studies and hence contributes to the current debate.

Regional Disparities in China’s Mainland at Provincial Level Between 2000 and 2005

In transboundary areas, harmonizing risk assessment across borders is essential for effective risk management. However, differing methodologies for seismic risk assessment used by different countries can yield unequal results on either side of the border. This study presents a framework for harmonized cross-border time-based risk assessment, built upon established seismic risk assessment practices at the national level. The framework considers cross-border hazard, exposure, fragility, and consequence models, aiming to harmonize different data sources, methodologies, and models. An emphasis is given to a heuristic approach for the harmonization of fragility curves defined in the national fragility models. The proposed framework is implemented for the Italian-Slovenian cross-border region defined by municipalities near Gorizia and Nova Gorica. The results reveal differences in seismic risk levels between the building stocks on the Slovenian and Italian sides, primarily due to higher building density, seismic hazard, and vulnerability in Italy, while the seismic risk to people was observed to be nearly equal for urban centers like Gorizia and Nova Gorica. These findings can be used to design joint strategies for long-term risk management of the analysed cross-border region. However, further research is needed, particularly to overcome limitations related to the data sources of the exposure models and methodologies for fragility and consequence models, which can be addressed over a long period through systematic standardization of cross-border seismic risk assessment.

SummaryAn efficient computational framework is presented for seismic risk assessment within a modeling approach that utilizes stochastic ground motion models to describe the seismic hazard. The framework is based on the use of a kriging surrogate model (metamodel) to provide an approximate relationship between the structural response and the structural and ground motion parameters that are considered as uncertain. The stochastic character of the excitation is addressed by assuming that under the influence of the white noise (used within the ground motion model) the response follows a lognormal distribution. Once the surrogate model is established, a task that involves the formulation of an initial database to inform the metamodel development, it is then directly used for all response evaluations required to estimate seismic risk. The model prediction error stemming from the metamodel is directly incorporated within the seismic risk quantification and assessment, whereas an adaptive approach is developed to refine the database that informs the metamodel development. The ability to efficiently obtain derivative information through the kriging metamodel and its utility for various tasks within the probabilistic seismic risk assessment is also discussed. As an illustrative example, the assessment of seismic risk for a benchmark four‐story concrete office building is presented. The potential that ground motions include near‐fault characteristics is explicitly addressed within the context of this example. The implementation of the framework for the same structure equipped with fluid viscous dampers is also demonstrated. Copyright © 2015 John Wiley & Sons, Ltd.

By comparison of the traditional seismic risk theory and the 2nd-generation Performance-Based Earthquake Engineering (PBEE) method, the two seismic risk assessment methods are unified in a new theoretical framework by expounding the meaning of seismic vulnerability and the definition of forward and backward analysis of PBEE. By use of both experimental and analytical fragility data, a hybrid fragility approach is proposed for continuous damage states of bridges under the 2nd-generation PBEE framework, and the theoretical framework is applied to seismic risk assessment of steel-concrete composite girder bridges commonly used in highway systems. The seismic functionality loss estimation model for bridges based on the vertical carrying capacity and a theoretical framework for seismic risk assessment based on functionality loss are further proposed. Considering the ability of functional recovery for bridges after earthquake events, a method for evaluating the seismic resilience of composite girder bridges considering functional loss is put forward. The framework and the method are applied to a bridge in Italy as a case study.

Quantifying and communicating uncertainty in seismic risk assessment

Optimization-based stacked machine-learning method for seismic probability and risk assessment of reinforced concrete shear walls