Adsorption of Two Taste and Odor Compounds IPMP and IBMP by Granular Activated Carbon in Water

Granular activated carbon (GAC) adsorption of two representative taste and odor (T & O) compounds, 2‐isopropyl‐3‐methoxy pyrazine (IPMP), and 2‐isobutyl‐3‐methoxy pyrazine (IBMP), in drinking water was investigated. Results show that the modified Freundlich equation best fit the experimental data during the adsorption isotherm tests, and the pseudo first‐order kinetics and intra‐particle diffusion kinetics well described the adsorption kinetics pattern. The calculated thermodynamic parameters (ΔH⁰, ΔS⁰, and ΔG⁰) indicated a spontaneous and endothermic adsorption process. Factors affecting the treatment efficiency were carefully evaluated. Acidic and alkaline conditions both favored GAC adsorption of IPMP and IBMP, especially the former. With the GAC dosage increasing, the first order adsorption rates increased, while the intra‐particle adsorption rates decreased. Within 12 h, 200 mg/L GAC could remove >90% of 150 µg/L IPMP and IBMP via adsorption at pH 3–11. Therefore, GAC is a promising treatment technology to control the T & O compounds associated water pollution.     

On the ecohydrology of the Yucatan Peninsula: Evapotranspiration and carbon intake dynamics across an eco‐climatic gradient

The hydrology and productivity of the ecosystems of the Yucatan Peninsula (YP) are highly constrained by two factors: (a) the lack of surface drainage networks due to the existence of a highly permeable and connected karstic aquifer roughly the size of the peninsula and (b) a climatic gradient that leads to a transition from seasonally dry deciduous and sub‐deciduous tropical forests, in the north‐western and central parts of the Peninsula, to evergreen forests, in the southern and eastern parts. As a result, surface water fluxes of the YP are restricted to evapotranspiration (ET) that are tightly coupled to ecosystems health and gross primary productivity (GPP). The magnitude and seasonal variation of these fluxes are sensitive to climatic variability and perturbations caused by extreme events such as droughts and tropical storms that are frequent in the YP. In this study, we assess the spatio‐temporal dynamics of ET and GPP above average dry and wet conditions through time series analyses of 15 years of remotely sensed data from both Moderate Resolution Imaging Spectroradiometer and Tropical Rainfall Measuring Mission satellite products. Our results show that ET and GPP follow a regional moisture and temperature gradient that highly controls the distribution of ecosystems within the peninsula. We observe that ET and GPP are in phase with the rainy season in the deciduous forests, but for the evergreen forests, only the GPP is in phase. Additionally, and with the exception of droughts on deciduous ecosystems of the northern part of the YP, the productivity of these ecosystems shows a legacy effect, responding more to a defined trajectory (wetting or drying on the previous years), rather than to punctual extreme climatic events. This has implications on the resilience of these ecosystems to natural perturbations of climate. Comparisons between deciduous and evergreen forest indicate that both types of ecosystems have different plant water use strategies in response to hydrologic variability.     

Use of the Anion‐Exchange Resin Amberlite IRA‐93 for the Separation of Arsenite and Arsenate in Aqueous Samples

The method described uses the separation of As(III) and As(V) species in aqueous samples by means of the anion‐exchange resin Amberlite IRA‐93. The samples were acidified using acetic acid and passed through a glass column filled with pre‐treated Amberlite IRA‐93 resin. As(III) was poorly adsorbed on the anionic exchanger material, whereas As(V) was retained. The arsenic concentration was measured in the column effluent by graphite furnace AAS (GF‐AAS). The retained As(V) was eluted from the column using 1 M NaOH. Prior to the determination of the As(V) concentration in the NaOH eluate, the eluate was passed through a glass column filled with a cation‐exchange resin (Amberlite 200) to remove sodium ions and minimize the Na⁺ interference with the AAS determination. After calibration the method was applied to the separation of As(III) and As(V) species in two aqueous extracts of arsenic contaminated soils. The results were compared with those obtained from an on‐line separation and determination of As(III) and As(V) in the aqueous soil extracts using a state of the art HPLC‐ICP‐MS system.     

The use of grain‐size distribution patterns to elucidate aeolian processes on a transverse dune of Thar Desert,India

The grain‐size distribution of aeolian dune sands in the Thar Desert, India was analyzed and compared with three model distributions – log‐normal, log‐hyberbolic and log‐skew‐Laplace – to determine the best‐fit statistical model. In total, 51 samples were collected along a single transect over a transverse dune, of which 15 were from the stoss side, 12 from the crest and 24 from the lee side. Samples were collected during a calm period in the afternoon of a winter's day. It was observed that of these 51 samples, 33 fit best to a log‐hyperbolic distribution, 14 fit best to a normal distribution and only four fit best to a Laplace distribution. However, it was further observed that of 24 samples from the lee side, 13 fit best to a normal distribution, eight fit best to a hyperbolic distribution, and three fit best to a Laplace distribution. Of 12 samples from the crest of the dune, 11 fit best to the log‐hyperbolic distribution, only one to the Laplace distribution but none to a normal distribution. Of 15 samples from the stoss side of the dune, only one sample best‐fits a normal distribution, 14 fit best to a log‐hyperbolic distribution, and none best fit to a Laplace distribution. During sample collection a calm period prevailed and there was no dusty wind. It was therefore assumed that in the initial stage a mixture of coarse, medium and fine sands was laid down on the stoss side of the dune. As wind speeds increased and saltation started, the coarser fractions were segregated and lagged behind on the stoss slope. In the final stage when the remaining intermediate and finer fractions reached the dune crest, the finer fractions were winnowed away to suspension from the crest of the dune. As a result, a narrow range of intermediate sized sediments was deposited by rolling down the lee side to explain the development of log‐normality. In such a situation, both the coarser and finer fractions, to which the skewed distributions can be attributed, are separated from the initial mixture of coarse, intermediate and fine fractions. Hence the main criteria for the development of a normal distribution is the lack of skewed fractions and the concentration of the narrow, intermediate size fractions in the final grain size distribution. This is also corroborated with the index of symmetry, which is a measure of the difference between the angle of two slopes of the hyperbolic distribution as represented by the coarser and finer fractions. Copyright © 2010 John Wiley & Sons, Ltd.     

Multi‐directional response of unreinforced masonry walls: experimental and computational investigations

This paper describes the results of an experimental and numerical study that focused on multi‐directional behavior of unreinforced masonry walls and established the requisite of the related proposed design equations. The tests were conducted following several sets of multi‐directional loading combinations imposed on the top plane of the wall along with considering monotonic and cyclic quasi‐static loading protocols. Various boundary conditions, representing possible wall–roof connections, were also considered for different walls to investigate the influence of rotation of the top plane of the wall on the failure modes. The results of the tests were recorded with a host of high precision data acquisition systems, showing three‐dimensional displacements of a grid on the surface of the wall. Finite element models of the walls are developed using the commercial software package ABAQUS/Explicit compiled with a FORTRAN subroutine (VUMAT) written by the authors. The experimental results were then used to validate the finite element models and the developed user‐defined material models. With the utility of validated models, a parametric study was performed on a set of parameters with dominant influence on the behavior of the wall system under in‐plane and out‐of‐plane loading combinations. The experimental and numerical results are finally used to investigate the adequacy of ASCE 41 empirical equations, and some insights and recommendations are made. Copyright © 2016 John Wiley & Sons, Ltd.     

Preconcentration by Coprecipitation of Copper and Nickel with Mo(VI)/Triazole Derivative System and Their Determinations by Flame Atomic Absorption Spectrometry in Food and Water Samples

A new separation and preconcentration technique based on coprecipitation of Cu(II) and Ni(II) ions by the aid of Mo(VI)/di‐tert‐butyl{methylenebis[5‐(chlorobenzyl)‐4H‐1,2,4‐triazol‐3,4‐diyl]}biscarbamate (BUMECTAC) precipitate has been established. The Mo(VI)/BUMECTAC precipitate was dissolved by concentrated HNO₃ and the solution was completed to 5.0 mL with distilled/deionized water. The levels of the analyte ions were determined by flame atomic absorption spectrometer. The effects of experimental conditions like HNO₃ concentration, amount of BUMECTAC and Mo(VI), sample volume, etc. and also the influences of some foreign ions were investigated in detail on the quantitative recoveries of analyte ions. The preconcentration factors were found to be 40 for Cu(II) and 100 for Ni(II) ions. The detection limits for Cu(II) and Ni(II) ions based on 3σ (N:10) were 0.43 and 0.70 µg L^?1, respectively. The relative standard deviations were found to be lower than 4.0% for both analyte ions. The accuracy of the method was checked by spiked/recovery tests and the analysis of two certified reference materials (Environment Canada TM‐25.3 and CRM‐SA‐C Sandy Soil C). The procedure was successfully applied to sea water and stream water as liquid samples and baby food as solid sample in order to determine the levels of Cu(II) and Ni(II) ions.     

Grain‐size distribution patterns of a point bar system in the Usri River,India

Grain‐size distribution patterns in a point bar system of the Usri River, India, were critically analysed in the light of log‐normal, log‐hyperbolic and log‐skew‐Laplace distribution models. Sand samples were collected from the cross‐bedding foreset of different sizes of bedform; the objectives were to (i) study whether bedform heights have any role in grain‐size distribution patterns, (ii) offer a best‐fit statistical model, (iii) study the downstream variation of size‐sorting in a point bar system, and (iv) study the mechanism of grain sorting. The results indicate that the bedform heights have no role in grain‐size distribution patterns. Quantitatively when the errors in three distribution models were analysed, it was observed that the log‐normal distribution is the best‐fit statistical model and the next one is the log‐skew‐Laplace. However, in the upper reaches of the river, log‐normal distribution is the best‐fit model in the case of large bedforms, whereas in the lower reaches the log‐normal model is the best‐fit one in the case of small bed forms. It is also observed that within a point bar, for large and small bedforms, there is a tendency for mean grain size to decrease downstream. Between point bars for large bedforms there is no consistency in decreasing grain size downstream, whereas for small bed forms the decrease of grain size downstream is observed except near the confluence at Palkia. With distance of transport, the coarser and finer fractions of sediments are gradually chopped off. The coarser fractions are buried below the advancing bedforms on the lee sides and the finer ones are transported further downstream. Thus the finer admixture giving rise to the fining‐upward sequence overlies a carpet of coarser materials. This mechanism provides a clue to the process of grain sorting in the fluvial environment. An interpretation has been offered for the log‐normality of the grain‐size distribution pattern. During prolonged transportation in a fluvial environment, the larger grain‐size fractions are gradually chopped off and buried below the advancing bedforms on their lee sides. On the other hand, the finer fractions are transported further downstream in suspension. Thus the narrow, intermediate size fraction takes active part in the distribution patterns leading to the generation of unimodality and a symmetric distribution pattern downstream, which are the main criteria for log‐normality. Similarly, increase of bedform size is the effect of increase of stream power and Froude number leading to the selective segregation of bed materials. Thus the intermediate size fractions take a more active part than the coarser and the finer size fractions in developing log‐normality. Besides the hydrodynamic parameters of the Usri, coarsening of grain size downstream has been attributed to (i) the aggrading nature of the Usri downstream, and (ii) the contribution of coarser materials to the Usri by its tributaries and bank erosion. Copyright © 2006 John Wiley & Sons, Ltd.     

Sub‐optimal control of structures

It is well known that the classical optimal control method requires all the state variables of the controlled system to be measurable and available for control feedback. However, for a high‐order or complex system some state variables are possibly unmeasurable in practice. In addition, the control cost will be higher if more sensors are used, because it is expensive to install sensors. On the other hand, when using the optimal control method with full‐state feedback, some state variables in control feedback have only a small effect on control performance. Neglecting these state variables does not affect the control performance greatly. Good control effectiveness can be obtained by using only the state variables that have a big effect on the control performance. So the questions become how to determine those state variables which have a big effect on the control performance? and how to design the optimal controller using only the determined state variables? The discrete sub‐optimal control method with partial‐state feedback is investigated in this paper. Firstly, the continuous control system and performance index are both transformed into discrete forms. Then the state variables, which have a big effect on the control performance, are determined using the second‐order sensitivity which is the second‐order derivative of the performance index with respect to control gain. The sub‐optimal controller is finally designed using only the determined state variables. Numerical examples are worked out to demonstrate the application of the proposed control algorithm. It is shown that the relative importance of each state variable can be indicated clearly by the second‐order sensitivity. The sub‐optimal control method presented is effective in reducing maximum responses of the structure. Copyright © 2003 John Wiley & Sons, Ltd.     

Design of store‐release covers to minimize deep drainage in the mining and waste‐disposal industries: results from a modelling analyses based on ecophysiological principles

Sustainable long‐term storage of municipal waste and waste rock from mining activities in waste dumps (either above or below the land surface) requires minimization of percolation of rainwater into and then through stored waste material. There has been increasing attention given to the use of store‐release covers (transpirational covers) to achieve this. However, the design of such covers remains problematic because of the unique combinations of weather, vegetation composition, soils and their interactions that determine the efficacy of each design that could be available for the construction of the covers. The aim of the work described here was to use ecophysiological knowledge of soil‐plant‐atmosphere (SPA) interactions through the application of a detailed mechanistic model of the SPA continuum. We examined the relative influence of soil depth, soil texture, leaf area index and rainfall as determinants of rates of evapotranspiration and water budget for several different theoretical cover designs. We show that minimizing deep drainage requires a cover that has the following attributes: (i) a water storage capacity that is large enough to store the volume of water that is received as rainfall in above‐average wet months/seasons; (ii) a root distribution that explores the entire depth of the cover; (iii) a leaf area index that is present all year sufficient to evapotranspire monthly rainfall; and (iv) takes into account the intra‐annual and inter‐annual variability in rainfall and other climatic variables that drive ET. Copyright © 2012 John Wiley & Sons, Ltd.     

Handling dip discrimination phenomenon in common‐reflection‐surface stack via combination of output‐imaging‐scheme and migration/demigration

In the application of a conventional common‐reflection‐surface (CRS) stack, it is well‐known that only one optimum stacking operator is determined for each zero‐offset sample to be simulated. As a result, the conflicting dip situations are not taken into account and only the most prominent event contributes to any a particular stack sample. In this paper, we name this phenomenon caused by conflicting dip problems as ‘dip discrimination phenomenon’. This phenomenon is not welcome because it not only leads to the loss of weak reflections and tips of diffractions in the final zero‐offset‐CRS stacked section but also to a deteriorated quality in subsequent migration. The common‐reflection‐surface stack with the output imaging scheme (CRS‐OIS) is a novel technique to implement a CRS stack based on a unified Kirchhoff imaging approach. As far as dealing with conflicting dip problems is concerned, the CRS‐OIS is a better option than a conventional CRS stack. However, we think the CRS‐OIS can do more in this aspect. In this paper, we propose a workflow to handle the dip discrimination phenomenon based on a cascaded implementation of prestack time migration, CRS‐OIS and prestack time demigration. Firstly, a common offset prestack time migration is implemented. Then, a CRS‐OIS is applied to the time‐migrated common offset gather. Afterwards, a prestack time demigration is performed to reconstruct each unmigrated common offset gather with its reflections being greatly enhanced and diffractions being well preserved. Compared with existing techniques dealing with conflicting dip problems, the technique presented in this paper preserves most of the diffractions and accounts for reflections from all possible dips properly. More importantly, both the post‐stacked data set and prestacked data set can be of much better quality after the implementation of the presented scheme. It serves as a promising alternative to other techniques except that it cannot provide the typical CRS wavefield attributes. The numerical tests on a synthetic Marmousi data set and a real 2D marine data set demonstrated its effectiveness and robustness.     

Bioassay‐directed fractionation for analyzing estrogens in surface waters of the German Baltic Sea

A reversed‐phase fractionation method with subsequent biological and chemical analysis has been developed to estimate the contributions of the most potent estrogens to observed estrogenic effect potentials. Surface water samples were taken in the German Baltic Sea (Inner Wismar Bay and Darss Peninsula, sampling campaign July 2003) and were separated into seven individual fractions. Three fractions showed significant estrogenic activities and clear dose‐dependant responses were obtained in the yeast estrogen screen (YES). In the 2nd fractions liquid chromatographic‐electrospray‐tandem mass spectrometric (LC‐ESI‐MS‐MS) analyses showed the presence of bisphenol A (Inner Wismar Bay: 4.8 ng L^–1 and 6 ng L^–1; Darss Peninsula: 0.91 ng L^–1 and 1.7 ng L^–1) and ethinylestradiol (Inner Wismar Bay: 2.0 ng L^–1 and 6.0 ng L^–1; Darss Peninsula: < MDL and 1.7 ng L^–1), whereas estrogenic activities in the YES were only around 10% of the positive control E2. Although not identified prior in the total extract the natural hormones estradiol (Inner Wismar Bay: 0.13 ng L^–1 and 0.19 ng L^–1; Darss Peninsula: 0.12 ng L^–1 and 0.16 ng L^–1) and estriol (Inner Wismar Bay: < MDL and 0.33 ng L^–1; Darss Peninsula: < MDL) could be detected in the 3rd fractions, where high estrogenic potentials could be observed. The 4th fractions showed high responses as well and estrone were herein quantified with concentrations of 0.16 ng L^–1 and 0.18 ng L^–1 (Darss Peninsula) up to 0.37 ng L^–1 (Inner Wismar Bay). Measured and calculated estradiol equivalents for individual fractions correlated very well (R² = 0.78), when disregarding results of the 2nd fraction, where high deviations occurred.     

The non‐stationary cross‐correlation coefficients in the seismic analysis of MDOF structural systems

A method concerning the evaluation, in a very compact form, of the non‐stationary modal cross‐correlation coefficients of MDOF structural systems subjected to seismic excitations is presented. It is available both in the case when the excitation is considered as a white‐noise process and when it is considered as a filtered process. The evaluation of these coefficients is required when a transient seismic analysis is performed by the use of the modal response spectrum approach. This is necessary when the strong‐motion phase of the earthquake is significantly short with respect to the fundamental period of the structure. Copyright © 2003 John Wiley & Sons, Ltd.     

Residual displacement ratios for assessment of existing structures

Results of an analytical study aimed at evaluating residual displacement ratios, C_r, which allow the estimation of residual displacement demands from maximum elastic displacement demands is presented. Residual displacement ratios were computed using response time‐history analyses of single‐degree‐of‐freedom systems having 6 levels of relative lateral strength when subjected to an ensemble of 240 earthquake ground motions recorded in stations placed on firm sites. The results were statistically organized to evaluate the influence of the following parameters: period of vibration, level of relative lateral strength, site conditions, earthquake magnitude, and distance to the source. In addition, the influence of post‐yield stiffness ratio in bilinear systems and of the unloading stiffness in stiffness‐degrading systems was also investigated. A special emphasis is given to the uncertainty of these ratios. From this study, it is concluded that mean residual displacement ratios are more sensitive to changes in local site conditions, earthquake magnitude, distance to the source range and hysteretic behaviour than mean inelastic displacement ratios. In particular, residual displacement ratios exhibit large levels of record‐to‐record variability and, therefore, this dispersion should be taken into account when estimating residual displacements. A simplified expression is presented to estimate mean residual displacements ratios for elastoplastic systems during the evaluation of existing structures built on firm soil sites. Copyright © 2005 John Wiley & Sons, Ltd.     

Response of nonlinear soil‐MDOF structure systems subjected to distinct frequency‐content components of near‐fault ground motions

This paper is devoted to investigate the effects of near‐fault ground motions on the seismic responses of nonlinear MDOF structures considering soil‐structure interaction (SSI). Attempts are made to take into account the effects of different frequency‐content components of near‐fault records including pulse‐type (PT) and high‐frequency (HF) components via adopting an ensemble of 54 near‐fault ground motions. A deep sensitivity analysis is implemented based on the main parameters of the soil‐structure system. The soil is simulated based on the Cone model concept, and the superstructure is idealized as a nonlinear shear building. The results elucidate that SSI has approximately increasing and mitigating effects on structural responses to the PT and HF components, respectively. Also, a threshold period exists above which the HF component governs the structural responses. As the fundamental period of the structure becomes shorter and structural target ductility reduces, the contribution of the HF component to the structural responses increases, elaborately. Soil flexibility makes the threshold period increase, and the effect of the PT component becomes more significant than the HF one. In the case of soil‐structure system, slenderizing the structure also increases this threshold period and causes the PT component to be dominant. Copyright © 2013 John Wiley & Sons, Ltd.     

Fate of Lignin in the Process of Aerobic Biological Treatment of Paper Mill Wastewater

Although lignin is known to be not readily biodegradable the concentration of dissolved lignin decreased during aerobic biological treatment of paper mill wastewater performed in sequencing batch reactors (SBR). Systematic lab scale batch tests were conducted to clarify whether the observed removal of lignin was the result of biodegradation or adsorption onto the activated sludge. For the batch tests, sludge samples were taken from sequencing batch reactors operated at solid retention times (SRT) of 10, 15, 20, 30, and 40 days, respectively. The amount of lignin present in the bulk liquid and in the sludge samples was quantified by an analytical procedure comprising pyrolysis, gas chromatography and mass spectrometry (py‐GC/MS analysis). It was found that lignin adsorbs onto the activated sludge by up to 30%[TH]w/w. This demonstrates the sludge excellent adsorption properties. The ultimate removal of lignin is achieved by sludge wasting. The highest overall removal rate was found when sludge was used from the SBR run at SRT of 20 days.     

Seismic response analysis of adjacent liquid‐storage tanks

A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank‐liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross‐interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell‐liquid‐soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock. Copyright © 2016 John Wiley & Sons, Ltd.     

Out‐of‐plane effects in 2D borehole‐to‐surface resistivity tomography and applications in mineral exploration

In this paper, we discuss the effects of anomalous out‐of‐plane bodies in two‐dimensional (2D) borehole‐to‐surface electrical resistivity tomography with numerical resistivity modelling and synthetic inversion tests. The results of the two groups of synthetic resistivity model tests illustrate that anomalous bodies out of the plane of interest have an effect on two‐dimensional inversion and that the degree of influence of out‐of‐plane body on inverted images varies. The different influences are derived from two cases. One case is different resistivity models with the same electrode array, and the other case is the same resistivity model with different electrode arrays. Qualitative interpretation based on the inversion tests shows that we cannot find a reasonable electrode array to determine the best inverse solution and reveal the subsurface resistivity distribution for all types of geoelectrical models. Because of the three‐dimensional effect arising from neighbouring anomalous bodies, the qualitative interpretation of inverted images from the two‐dimensional inversion of electrical resistivity tomography data without prior information can be misleading. Two‐dimensional inversion with drilling data can decrease the three‐dimensional effect. We employed two‐ and three‐dimensional borehole‐to‐surface electrical resistivity tomography methods with a pole–pole array and a bipole–bipole array for mineral exploration at Abag Banner and Hexigten Banner in Inner Mongolia, China. Different inverse schemes were carried out for different cases. The subsurface resistivity distribution obtained from the two‐dimensional inversion of the field electrical resistivity tomography data with sufficient prior information, such as drilling data and other non‐electrical data, can better describe the actual geological situation. When there is not enough prior information to carry out constrained two‐dimensional inversion, the three‐dimensional electrical resistivity tomography survey is the better choice.     

Seismic resistance capacity of beam–column connections in high‐rise buildings: E‐Defense shaking table test

A series of E‐Defense shaking table tests are conducted on a large‐scale test specimen that represents a high‐rise steel building. Two types of connections featuring the connection details commonly used in 1970s, in the early days of high‐rise construction in Japan, are adopted: the field‐welded connection consisting of welded unreinforced flanges and a bolted web type, and the shop‐welded connection in which the flanges and web are all‐welded to the column flange in the shop. To examine the seismic capacity of a total of 24 beam‐to‐column connections of the specimen, particularly when it is subjected to long‐period ground motion characterized not so much by large amplitude as by very many cycles of repeated loading, the test specimen is shaken repeatedly until the connections fractured. The test results indicate that a few of the field‐welded connections fractured from the bottom flange weld boundary in a relatively small cumulative rotation primarily due to the difficulties in ensuring the welding and inspection performance in the actual field welding. The shop‐welded connections are able to sustain many cycles of plastic rotation, with an averaged cumulative plastic rotation of 0.86 rad. Two shop‐welded connections exhibit ductile fractures but only after experiencing many cycles. The presence of RC floor slabs promotes the strain concentration at the toe of the weld access hole in the bottom flange by at least twice compared with the case without the slab, which had resulted in a decrease in the cumulative plastic rotation by about 50%. Copyright © 2010 John Wiley & Sons, Ltd.     

Geostatistical interpolation of space–time rainfall on Tamshui River basin,Taiwan

Taiwan suffers from heavy storm rainfall during the typhoon season. This usually causes large river runoff, overland flow, erosion, landslides, debris flows, loss of power, etc. In order to evaluate storm impacts on the downstream basin, a real‐time hydrological modelling is used to estimate potential hazard areas. This can be used as a decision‐support system for the Emergency Response Center, National Fire Agency Ministry, to make ‘real‐time’ responses and minimize possible damage to human life and property. This study used 34 observed events from 14 telemetered rain‐gauges in the Tamshui River basin, Taiwan, to study the spatial–temporal characteristics of typhoon rainfall. In the study, regionalized theory and cross‐semi‐variograms were used to identify the spatial‐temporal structure of typhoon rainfall. The power form and parameters of the cross‐semi‐variogram were derived through analysis of the observed data. In the end, cross‐validation was used to evaluate the performance of the interpolated rainfall on the river basin. The results show the derived rainfall interpolator represents the observed events well, which indicates the rainfall interpolator can be used as a spatial‐temporal rainfall input for real‐time hydrological modelling. Copyright © 2007 John Wiley & Sons, Ltd.