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The use of liquefied natural gas (LNG) in the transportation sector is increasing, and boil-off gas (BOG) management systems are considered viable options to increase economic efficiency and reduce greenhouse gas emissions at LNG refueling stations. The present study proposed an economically optimized method by investigating four refueling station scenarios, including different BOG management systems. Among the four scenarios, the scenario in which compressed natural gas was produced from BOG had the lowest minimum selling price (MSP) and was the most economical. Sensitivity and uncertainty analyses were conducted for the economically optimal scenario, which identified the factors with the most influential impact and their uncertainties on the MSP. Finally, to determine the feasibility of the business through profitability analysis, the net present value, discounted payback period, and present value ratio due to changes in the discount rate were presented, and the discounted cash flow rate of return was found to be 13.22%. As a result of this study, a BOG management system can contribute to improving the economic feasibility for LNG refueling stations by reliquefying BOG and re-selling it (the most efficient way is scenario 4) and will provide an economical guide for countries with much demand for LNG in the transport sector.

In the present work, the global wind and wave climate is studied on the basis of two well-known reanalysis products, namely ERA5 and CFSR-W (WW3 hereafter). Several statistical features of the datasets are assessed, such as seasonal variability, quantiles of the probability distribution, monthly, annual and inter-annual variability, and several error metrics. The time span covers a period of 31 years (1979–2009), a fact that assures that most of the long-scale features are equally present in both datasets. The analysis performed is depicted both on a global and regional scale. The results are also assessed by means of a global satellite altimeter dataset.

As the impact factors of the waste Not-In-My-Back Yard (NIMBY) crisis are complex, and the scenario evolution path of it is diverse. Once the crisis is not handled properly, it will bring adverse effects on the construction of waste NIMBY facilities, economic development and social stability. Consequently, based on ground theory, this paper takes the waste NIMBY crisis in China from 2006 to 2019 as typical cases, through coding analysis, scenario evolution factors of waste NIMBY crisis are established. Furtherly, three key scenarios were obtained, namely, external situation (E), situation state (S), emergency management (M), what is more, scenario evolution law of waste NIMBY crisis is revealed. Then, the dynamic Bayesian network theory is used to construct the dynamic scenario evolution network of waste NIMBY crisis. Finally, based on the above models, Xiantao waste NIMBY crisis is taken as a case study, and the dynamic process of scenario evolution network is visually displayed by using Netica. The simulation results show that the scenario evolution network of Xiantao waste NIMBY crisis is basically consistent with the actual incident development process, which confirms the effectiveness and feasibility of the model.

This paper develops a new practical framework of high-cycle fatigue (HCF) probability analysis of local welded plate joints considering the uncertainty in Arctic areas. The framework includes 1) a meta-model of the local energy concentration factor relying on the genetic algorithm and neural network (GA-NN) approach, 2) the identification of uncertainties in the fatigue assessment procedure, and 3) the probability analysis relying on the Monte Carlo simulation with Latin hypercube sampling method. The GA-NN determines the interactive relationship among the geometrical properties for a good estimation of the energy-based indicator concentration factor. The probability analysis considers the uncertainty caused by the meat-model, the local welding geometry, the Young modulus under different temperatures, and the combination of the ice and wave loadings. To determine the uncertainties involved in probability analysis, this study conducts a series of experimental measurements and high-cycle fatigue tests of cruciform welded plate joints. Furthermore, this study discusses the effect of the ice loading, maximum wave stress, and main plate thickness of welded plate joints on the expected fatigue life. The additional ice loading on the welded plate joints can almost cut the expected fatigue life in 33% in comparison with that only under wave loadings, implying the necessity of considering ice loading in Arctic areas. This study also proposes a probability S-N curve with the cumulative probability of 50% based on the maximum local energy-based indicator to estimate the expected fatigue life. Ministry of Education (MOE) Nanyang Technological University The Ministry of Education Tier 1 Grants, Singapore (No. 04MNP000279C120, No. 04MNP002126C120) and the Start-Up Grant at Nanyang Technological University, Singapore (No. 04INS000423C120) are acknowledged for their financial support of this research

Hazard mapping is essential for risk assessment and mitigation measurement design in flood prone areas. In Europe, long-term fluvial stage data, acquired since the 18th century, represent a resource of fundamental importance in this perspective, especially where rivers monitoring is completed by multiple stations distributed along the course. In these conditions, a major challenge is represented by the possibility of incorporating multiple probability models, representative of river dynamics at different distance from the mouth, in flood hazard estimation over so large areas. In this paper, we propose a new procedure of hazard estimation based on LiDAR derived flood inundation model and multiple hydrometric time series that, using a specifically developed algorithm/code of interpolation/assignation of multiple probability models, has the potential to work at local to national scale providing reliable estimation also in presence of urban areas. We applied the developed procedure and associated algorithm/code to a selected study area in southern Italy, recently hit by a destructive flood event, and quantitatively evaluate model performance. Confidence interval computation provides an overview of uncertainty related to flood magnitude estimation by extreme value analysis, indicating a substantial uncertainty related to 500 years flood magnitude estimation. Sensitivity analysis indicates a high degree of robustness of the developed procedure. Result validation through comparison against the observed 2015 flood event indicates that the method has the potential to support flood hazard analysis at regional to national scale. Limits of method application are related to the basic assumption of stationarity of hydrologic time series that might be considered too “simplicistic” in a changing climate also related to the limited length of some time series that only in few cases have no discontinuities. The absence of propagation modelling as part of the estimation procedure might be considered as an additional limit since in complex topographic and hydrological conditions it might provide a better evaluation of flood hazard. However, comparison of the 500 years flood derived from our procedure and 500 years flood scenarios derived by 2D hydraulic simulations indicate the capabilities of our procedure in identifying area floodable by specific events with only local overestimation that generally increase safety in human life protection perspective. This confirms the potential of considering multiple probability models distributed along the river course in flood hazard estimation perspective and indicate that our procedure can be a valid alternative to simulation based flood hazard estimation procedures.

The environmental impact potentials of producing bioethanol from corn stover were systematically assessed by life cycle assessment using datasets reported in the literature. The 15% best datasets with respect to global warming potential for seven different technological configurations were extracted from a published database reviewing 474 publications on converting corn stover to bioethanol. A total of 10 impact categories were evaluated. The impacts included both environmental loads and savings, and generally ranged from −0.1 to 0.1 person-equivalent per ton of dry corn stover for most non-toxic impacts and −0.2 to 0.5 person-equivalent for toxic impacts. Fossil fuel substitution with bioethanol provided savings in most impact categories, and so did the energy recovered from the residues, while enzyme production was a significant load. The treatment and discharge of effluent from the liquid residues may constitute a significant load to the environment. Based on the cumulative probabilities of overall environmental performance together with the bioethanol amount produced, the prioritisation of technologies for further development should be as follows: steam explosion (S4) and ammonia-based (S6) technologies as the highest priorities with approximately 100% and 40% probabilities to have savings in non-toxic and toxic impacts, respectively; acid (S1), alkaline (S2) and fungi (S7) technologies as medium priorities and solvent-based (S3) and liquid hot water (S5) technologies have the lowest priorities. We suggest the integration of life cycle assessment modelling to the research and development of biofuel production from biomass waste to ensure that the technologies being developed for full-scale applications are sustainable.

Conventional standard procedure used to determine the design value of a headed stud shear resistance in composite steel-concrete beams is very simple but, in fact, mathematically incorrect, particularly in the case when such connector is automatically welded and when it is working in a solid slab. According to this approach the considered value is specified as a minimum of two separate design values. One of them is related to the resistance of the stud itself while the other is associated with the failure of the surrounding concrete. In the paper presented by the authors a new algorithm which allow to evaluate this value is recommended and discussed in detail. It seems to be more accurate because it is based on the fully probabilistic inference. In such approach a new random variable is introduced, being a minimum of two other, statistically independent, random variables. Analogously as it is in the concept previously mentioned, the first random variable quantifies now the steel stud shear resistance whereas the second one – the resistance of the adjacent concrete. Consequently, the sought design value is determined as a suitable quantile of this new random variable, characterized by log-normal probability distribution. It is shown that the design value of a headed stud shear resistance, calculated in this manner, strongly depends on the variability of strength parameters, relating both to the steel of which the connecting stud is made and to the concrete of the slab. In addition, it is found that in the case when the variability of concrete strength is too high, the safety factor recommended to use in European standards is not able to provide the required safety level, acceptable by the building users. The considerations presented in the article are illustrated by a detailed computational example.

On 15 October 2015, a storm-induced flood hit the central sector of Benevento Province (southern Italy) causing two deaths and severe damage to infrastructure, buildings and local agriculture. This area has a long history of similar events and since 1924 its major river segments have been monitored with several hydrometric stations. We used data from two of these stations and a LiDAR derived high-resolution topography to develop a flood hazard map. For map computation, we first derived a flood inundation map from topography. Subsequently we estimated the probability of exceedance of each specific fluvial stage from the combination of a Generalized Extreme Value and a Gamma fits of available hydrometric data. As boundary condition, we considered a reference scenario corresponding to an estimated 500 year flood. The hazard maps provide an overview of the flood hazard in the central sector of Benevento Province and floodplains zonation in flood perspective. © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps.

During the last decades, fluorescence spectroscopy has emerged as a powerful tool in the fields of biophysics, biotechnology, biochemistry, cellular biology and the medical sciences. These techniques are highly sensitive, and allow us to study the structure and dynamics of (bio)molecular systems (Valeur 2001). A significant advantage of fluorescence techniques is that they can often be non-invasive and measurements can be performed in real time. In this thesis different advanced fluorescence methods will be used to study two important biological processes: (1) DNA dynamics and (2) plant photosynthesis. The first part aims at improving the smFRET technique for the analysis of DNA dynamics and other fast conformational changes. This improvement is made by combining and developing instrumentation and data evaluation tools. The second part is the continuous development of time-resolved fluorescence spectroscopy methods, as well their application in the field of photosynthesis to study ultrafast processes in thylakoid membranes and leaves. The two fluorescence techniques are technically and conceptually very different, but they are both designed for analysis of biomolecular systems. In this thesis, the techniques are applied to study energy transfer and dynamical changes in DNAs, thylakoid membranes and leaves. REFERENCE: VALEUR B 2001. Molecular Fluorescence: Principles and Applications. 1 ed: Wiley-VCH.

Marine operators are confronted with the new air emissions regulations that determine the limits of sulfur content in marine fuels. The low-sulfur (LS) marine fuels have a higher price, and their fluctuation is almost similar to the fluctuation of high-sulfur (HS) fuels. The price difference between HS and LS might also determine the decision of operators for alternative technical means, such as scrubbers, in order to comply with the new limits. This paper aims to provide a thorough statistical analysis of the currently available LS and HS marine fuels time series, as well as to present the analysis of the differential of the HS and LS fuel prices. The paper concludes with suggestions for further research.

In this paper, a procedure for the probabilistic treatment of solar irradiance and wind speed data is reported as a method of evaluating, at a given site, the electric energy generated by both a photovoltaic system and a wind system. The aim of the proposed approach is twofold: first, to check if the real probability distribution functions (PDFs) of both clearness index and wind speed overlap with Hollands and Huget and Weibull PDFs, respectively; and then to find the parameters of these two distributions that best fit the real data. Further, using goodness-of-fit tests, these PDFs are compared with another set of very common PDFs, namely the Gordon and Reddy and Lognormal functions, respectively. The results inform the design of a pre-processing stage for the input of an algorithm that probabilistically optimizes the design of hybrid solar wind power systems. In this paper, the validity of the proposed procedure was tested using long-term meteorological data from Acireale (Italy). Copyright © 2010 John Wiley & Sons, Ltd.

Continuous circuit miniaturization and increased process variability point to a future with diminishing returns from dynamic voltage scaling. Operation below Vcc-min has been proposed recently as a mean to reverse this trend. The goal of this paper is to minimize the performance loss due to reduced cache capacity when operating below Vcc-min. A simple method is proposed: disable faulty blocks at low voltage. The method is based on observations regarding the distributions of faults in an array according to probability theory. The key lesson, from the probability analysis, is that as the number of uniformly distributed random faulty cells in an array increases the faults increasingly occur in already faulty blocks. The probability analysis is also shown to be useful for obtaining insight about the reliability implications of other cache techniques. For one configuration used in this paper, block disabling is shown to have on the average 6.6% and up to 29% better performance than a previously proposed scheme for low voltage cache operation. Furthermore, block-disabling is simple and less costly to implement and does not degrade performance at or above Vcc-min operation. Finally, it is shown that a victim-cache enables higher and more deterministic performance for a block-disabled cache. ©2010 IEEE. 223 234 Sponsors: IEEE Computer Society NSF Intel Conference code: 80374 Cited By :13

For third generation systems and ultrawideband systems, RAKE receivers have been introduced due to the advantage of RAKE receivers which is their ability to combine different replicas of the transmitted signal arriving at different delays in a rich multipath environment. In principle, RAKE receivers combine all resolvable paths which gives the best performance in a rich diversity environment. However, this is usually costly in terms of hardware required as the number of RAKE fingers increases. Therefore, generalized selection combining (GSC) RAKE reception was proposed and has been studied by many researcher as an alternative to the classical two fundamental diversity schemes: maximal ratio combining and selection combining. Previous work on performance analyses of GSC RAKE receivers based on the signal to noise ratio focused on the development of methodologies to derive exact closedform expressions for various performance measures. However, the remaining set of uncombined paths affect the overall performance both in terms of loss in power. Therefore, to have a full understanding of the performance of GSC RAKE receivers, we introduce in this paper the notion of capture probability, which is defined as the ratio of the captured power (essentially combined paths power) to that of the total available power. The major difficulty in these problems is to derive some joint statistics of ordered exponential variates. With this motivation in mind, we capitalize in this paper on some new order statistics results to derive exact closed-form expressions for the capture probability over independent and identically distributed Rayleigh fading channels. Scopus