Life cycle cost analysis of alternative vehicles and fuels in Thailand

High crude oil prices and pollution problems have drawn attention to alternative vehicle technologies and fuels for the transportation sector. The question is: What are the benefits/costs of these technologies for society? To answer this question in a quantitative way, a web-based model (http://vehiclesandfuels.memebot.com) has been developed to calculate the societal life cycle costs, the consumer life cycle costs and the tax for different vehicle technologies. By comparing these costs it is possible to draw conclusions about the social benefit and the related tax structure. The model should help to guide decisions toward optimality, which refers to maximum social benefit. The model was applied to the case of Thailand. The life cycle cost of 13 different alternative vehicle technologies in Thailand have been calculated and the tax structure analyzed.     

Bioenergy,food security and poverty reduction: trade-offs and synergies along the water–energy–food security nexus

This article provides a review of trade-offs and synergies of bioenergy within the water–energy–food security nexus, with emphasis on developing countries. It explores the links of bioenergy with food security, poverty reduction, environmental sustainability, health, and gender equity. It concludes that applying the nexus perspective to analyses of bioenergy widens the scope for achieving multiple-win outcomes along the above aspects.     

Optimal setpoint chasing in dynamic positioning of deep‐water drilling and intervention vessels

Conventional controller designs for dynamic positioning of ships and floating marine structures have so far been based on the principle on automatic positioning in the horizontal‐plane about desired position and heading co‐ordinates defined by the operator. A three degrees‐of‐freedom multivariable controller either of linear or nonlinear type, normally with feedback signals from surge, sway and yaw position and velocities, has been regarded as adequate for the control objective. For floating structures with small waterplane area such as semi‐submersibles, feedback from roll and pitch angular rotation velocity may also be included to avoid thrust‐induced roll and pitch motions that are caused by the hydrodynamic and the geometrical couplings between the horizontal and vertical planes. However, for certain marine operations this control philosophy may not be the most appropriate approach ensuring safety and cost effectiveness. For drilling and work‐over operations the main positioning objective is to minimize the bending stresses along the riser and the riser angle magnitudes at the well head on the subsea structure, and at the top joint as well. A positioning control strategy solely based on manual setting of the desired position co‐ordinates may not be the most optimal solution for these applications. In this paper a new hybrid dynamic positioning controller, that also accounts for riser angle offsets and bending stresses is proposed. It is shown that a significant reduction in riser angle magnitude can be achieved. Simulations with a drilling semi‐submersible demonstrate the effect of the proposed control strategy. Copyright © 2001 John Wiley & Sons, Ltd.     

Identification of Parametric Variations of Structures Based on Least Squares Estimation and Adaptive Tracking Technique

An important objective of health monitoring systems for civil infrastructures is to identify the state of the structure and to detect the damage when it occurs. System identification and damage detection, based on measured vibration data, have received considerable attention recently. Frequently, the damage of a structure may be reflected by a change of some parameters in structural elements, such as a degradation of the stiffness. Hence it is important to develop data analysis techniques that are capable of detecting the parametric changes of structural elements during a severe event, such as the earthquake. In this paper, we propose a new adaptive tracking technique, based on the least-squares estimation approach, to identify the time-varying structural parameters. In particular, the new technique proposed is capable of tracking the abrupt changes of system parameters from which the event and the severity of the structural damage may be detected. The proposed technique is applied to linear structures, including the Phase I ASCE structural health monitoring benchmark building, and a nonlinear elastic structure to demonstrate its performance and advantages. Simulation results demonstrate that the proposed technique is capable of tracking the parametric change of structures due to damages.     

The Internal Pressure Test in Experiment and Simulation—Influence of the Wall Thickness Variation and the Change of the Packaging Behavior after the Impact of Standard Liquids

The effect of the wall thickness variation of blow‐moulded bodies made of high‐density polyethylene on an internal pressure test after prestoring the packaging with standard liquids was evaluated in experiments and simulations. The objects of the investigation were jerrycans used for the transportation and storage of dangerous goods. The wall thickness was determined using two alternative methods to the magnetostatic measurement. These alternative methods are used for research purpose to get a volumetric model of the jerrycan wall as a geometric model for the simulation. The comparison of the experiments and the simulations of the internal pressure test were performed using the digital image correlation method. The integral strain and deformation of the whole jerrycan was detected by measuring the total mass of the jerrycan being filled with water during the internal pressure test. This is a suitable alternative to the optical measurements of local deformation by the digital image correlation method. Prestorage at 40 °C without the influence of chemicals strengthens the jerrycan, whereas the swelling effect of butyl acetate and hydrocarbon mixture softens the jerrycan. The comparison with the experiment is necessary to verify the accuracy of the simulation. It shows that the deformation can be simulated more precisely by using the actual measured geometry. The weakening of the high‐density polyethylene caused by a hydrocarbon mixture can be simulated using the Arrhenius equation. The aim of the simulation was to discover whether it is possible to use specimens to predict the behaviour of a packaging both after the influence of standard liquids. Copyright © 2012 John Wiley & Sons, Ltd.     

Measurement of Helium Leakage Rates through Closures of Dangerous Goods Packagings for the Assessment of Potentially Explosive Mixtures in Freight Containers

The objective was to find out whether an explosive atmosphere can be created in a freight container by gaseous leakage flow of vapour‐air‐mixture through leaks in the closures of dangerous goods packagings filled with hazardous liquids. Because of high temperatures during intercontinental carriage, there is a gauge pressure in the free vapour phase inside the packagings which can cause a gaseous leakage flow. Two different methods were applied: Helium limit leakage rates for 23 quantitatively important hazardous liquids concerning their lower explosion limit (LEL) were calculated for a worst case transport scenario (Method 1). Helium leakage rates of five closure types of dangerous goods packagings with volumes of approximately 6 l were measured using the pressure technique by accumulation (Method 2). All types of closures of steel packagings were uncritical. The maximum measured leakage was 33% of the limit leakage rate. The leakage rates of screw closures of plastic jerricans can exceed the LEL if there are production‐related patterns such as non‐concentricity of the closures and flashes on the neck. Especially for plastic packagings it is important to minimize gaseous leakage flow, because an explosive atmosphere can also be reached by permeation of the individual filling substance or by a combination of both effects. For the assessment of potentially explosive mixtures in freight containers, both mass transfer mechanisms have to be taken into account. Copyright © 2015 John Wiley & Sons, Ltd.     

Determination of radon exhalation from construction materials using VOC emission test chambers

The inhalation of ²²²Rn (radon) decay products is one of the most important reasons for lung cancer after smoking. Stony building materials are an important source of indoor radon. This article describes the determination of the exhalation rate of stony construction materials by the use of commercially available measuring devices in combination with VOC emission test chambers. Five materials – two types of clay brick, clinker brick, light‐weight concrete brick, and honeycomb brick – generally used for wall constructions were used for the experiments. Their contribution to real room concentrations was estimated by applying room model parameters given in ISO 16000‐9, RP 112, and AgBB. This knowledge can be relevant, if for instance indoor radon concentration is limited by law. The test set‐up used here is well suited for application in test laboratories dealing with VOC emission testing.     

Multiple change-point detection with a genetic algorithm

 A common change-point problem is considered where the population mean of a random variable is suspected of undergoing abrupt changes in course of a time series. It is usual in practice that no information on positions or number of such shifts is available beforehand. Finding the change points, i.e. the positions of the shifts, in such a situation is a delicate statistical problem since any considered sample may actually represent a mixture of two or more populations where values from both sides of a yet unrecognized change point are unconsciously assembled. If this is the case, underlying assumptions of an employed statistical two-sample test are usually violated. Consequently, no definite decision should be based on just one value of the test statistic. Such a value is rather, as a precaution, to be regarded as an only approximate indicator of the quality of a hypothesis about change-point positions. Given these conclusions, it is found imperative to treat the problem of multiple change-point detection as one of global optimization. A cost function is constructed in such a manner that the change-point configuration yielding the global optimum is compliant with statistical-theoretical requirements to the utmost extent. The used advanced optimization tool, a genetic algorithm, is both efficient – as it takes advantage of the information about promising change-point positions encountered in previously investigated trial configurations – and flexible (as it is open to any modification of the change-point configuration at any time). Experiments using numerical simulation confirm adequate performance of the method in an application where a common change-point detection procedure based on Student's two-sample t-test is used to detect an arbitrary number of shifts in the mean of a normally distributed random variable.     

Attention capture by novel stimuli.

In several experiments, observers were given glimpses of 4-word arrays. Accuracy of word localization was tested after each array. Some words, called familiar, appeared many times across the series of arrays; others, called novel, appeared only once. The ratio of novel to familiar words in an array ranged from 0:4 to 4:0. When familiar and novel words were not intermixed (in 0:4 and 4:0 arrays), localization accuracy was higher for familiar words. However, when they were intermixed, especially in 1:3 arrays, accuracy tended to be higher for the novel words. This novel popout effect was the outcome of the suppressed localizability of the familiar words (relative to the 0:4 baseline) and the enhanced localizability of the novel words (relative to the 4:0 baseline). Novel popout may reflect an automatic orientation of attention away from more fluently unfolding regions of the perceptual field (familiar objects) and toward less fluently unfolding regions (novel objects). (PsycINFO Database Record (c) 2010 APA, all rights reserved)