Academic literature on the topic 'Return-to-base model'
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Journal articles on the topic "Return-to-base model"
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Cooray, Vernon, Marcos Rubinstein, and Farhad Rachidi. "Modified Transmission Line Model with a Current Attenuation Function Derived from the Lightning Radiation Field—MTLD Model." Atmosphere 12, no. 2 (February 13, 2021): 249. http://dx.doi.org/10.3390/atmos12020249.
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In return strokes, the parameters that can be measured are the channel base current and the return stroke speed. For this reason, many return stroke models have been developed with these two parameters, among others, as inputs. Here, we concentrate on the current propagation type engineering return stroke models where the return stroke is represented by a current pulse propagating upwards along the leader channel. In the current propagation type return stroke models, in addition to the channel base current and the return stroke speed, the way in which the return stroke current attenuates along the return stroke channel is specified as an input parameter. The goal of this paper is to show that, within the confines of current propagation type models, once the channel base current and the return stroke speed are known, the measured radiation field can be used to evaluate how the return stroke current attenuates along the channel. After giving the mathematics necessary for this inverse transformation, the procedure is illustrated by extracting the current attenuation curve from the typical wave shape of the return stroke current and from the distant radiation field of subsequent return strokes. The derived attenuation curve is used to evaluate both the subsequent and first return stroke electromagnetic fields at different distances. It is shown that all the experimentally observed features can be reproduced by the derived attenuation curve, except for the subsidiary peak and long zero-crossing times. In order to obtain electromagnetic fields of subsequent return strokes that are in agreement with measurements, one has to incorporate the current dispersion into the model. In the case of first return strokes, both current dispersion and reduction in return stroke speed with height are needed to obtain the desired features.
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Kiky, Andreas. "Analisis Sektor Industri Pertanian pada Model CAPM." ULTIMA Management 7, no. 1 (June 1, 2015): 14–24. http://dx.doi.org/10.31937/manajemen.v7i1.921.
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The most popular Asset Pricing that has been known for long time was CAPM. This model offers very simple approach and strong fundamental theory for financial literature. Base of previous research using time-series data, this model show very good explanation in explain variation of portfolio return. Aim of this research is to find some pattern in different industrial sector, especially agriculture sector. Keywords: CAPM, Empirical Evidence, Abnormal Return, Stock Return
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Javor, V. "Modeling of Lightning Strokes Using Two-Peaked Channel-Base Currents." International Journal of Antennas and Propagation 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/318417.
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Lightning electromagnetic field is obtained by using “engineering” models of lightning return strokes and new channel-base current functions and the results are presented in this paper. Experimentally measured channel-base currents are approximated not only with functions having two-peaked waveshapes but also with the one-peaked function so as usually used in the literature. These functions are simple to be applied in any “engineering” or electromagnetic model as well. For the three “engineering” models: transmission line model (without the peak current decay), transmission line model with linear decay, and transmission line model with exponential decay with height, the comparison of electric and magnetic field components at different distances from the lightning channel-base is presented in the case of a perfectly conducting ground. Different heights of lightning channels are also considered. These results enable analysis of advantages/shortages of the used return stroke models according to the electromagnetic field features to be achieved, as obtained by measurements.
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Shaw, Lynn, and Helene Polatajko. "An Application of the Occupation Competence Model to Organizing Factors Associated with Return to Work." Canadian Journal of Occupational Therapy 69, no. 3 (June 2002): 158–67. http://dx.doi.org/10.1177/000841740206900306.
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The variations in return to work outcomes for ill or injured persons experiencing health leaves are complex. However, it is important to comprehend these variations in order to develop evidenced-based practice in work rehabilitation. Currently, a plethora of studies exist in the literature that have attempted to explain the variations in work outcomes. A 20-year review of the literature on work outcomes has revealed several limitations in using this knowledge in occupational therapy. The study of return to work outcomes is, for the most part, atheoretical and the knowledge base is fragmented and disorganized. In addition, the literature does not reflect a consistent understanding of the multidimensional nature of either work disability or the facilitators for return to work. In this paper, the Occupational Competence Model is presented as a framework for filling this gap. This model is used here to organize and synthesize the factors previously studied on work outcomes to foster an understanding of this literature from an occupational therapy perspective and the future study of work outcomes and work rehabilitation.
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Alabdulkader, A. M., A. I. Al-Amoud, and F. S. Awad. " Optimization of the cropping pattern in Saudi Arabia using a mathematical programming sector model." Agricultural Economics (Zemědělská ekonomika) 58, No. 2 (March 5, 2012): 56–60. http://dx.doi.org/10.17221/8/2011-agricecon.
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A mathematical sector model has been formulated to optimize the cropping pattern in Saudi Arabia aiming at maximizing the net annual return of the agricultural sector in Saudi Arabia and ensuring the efficient allocation of the scarce water resources and arable land among the competing crops. The results showed the potential for Saudi Arabia to optimize its cropping pattern and to generate an estimated net return equivalent to about 2.42 billion US$ per year. The optimized cropping pattern in Saudi Arabia has been coupled with about 53% saving in the water use and about 48% reduction in the arable land use compared to the base-year cropping pattern. Comparable weights was given to different crop groups by allocating about 48.4%, 35.4%, 13.1%, and 3.2% to grow cereals, fruits, forages, and vegetables, respectively. These findings were in line with the national strategy to rationalize the cultivation of water-intensive crops in favour of highly water-efficient crops.
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Li, Ong Sheue. "TESTING FOR LINEAR AND NONLINEAR GRANGER CAUSALITY IN THE STOCK RETURN AND STOCK TRADING VOLUME RELATION: MALAYSIA AND SINGAPORE CASES." Labuan Bulletin of International Business and Finance (LBIBF) 9 (April 16, 2014): 44–57. http://dx.doi.org/10.51200/lbibf.v9i.1345.
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This study aims at examining the short-run linear and nonlinear Granger causality between stock return and trading volume in Malaysia and Singapore cases based on the Vector Autoregression (VAR) model and Taylor expansion of the nonlinear model, proposed by PéguinFeissolle, et al. (2008), respectively. We find evidence of significant bidirectional nonlinear causality between returns and trading volume in Malaysia case while unidirectional nonlinear causality from trading volume to stock return in Singapore case, which may establish useful base for future empirical work in considering nonlinearity studies for the dynamic relationship of stock return and trading volume.
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Guo, Pan, Yanlin Jia, Junwei Gan, and Xiaofeng Li. "Optimal Pricing and Ordering Strategies with a Flexible Return Strategy under Uncertainty." Mathematics 9, no. 17 (August 30, 2021): 2097. http://dx.doi.org/10.3390/math9172097.
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To coordinate the supply chain risk caused by demand uncertainty, this paper proposed a flexible return strategy under demand uncertainty, in which the retailer can choose return quantity independently by put option after the selling season, while the return quantity is usually determined by the supplier in the classical return strategy. In our novel return strategy, the exercise price is not fixed, and we developed the base model of this strategy, named the selective buyback contracts model. We have solved the optimal pricing and ordering strategies of supply chain members. Numerical studies demonstrated that the contracts can coordinate a supply chain with one retailer and one supplier, and the supplier can adjust the profit distribution of the supply chain by adjusting the option exercise price. Compared with other return strategies, the selective buyback contracts give the retailer more power of choice, and the supplier receives risk compensation from the put options.
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Fu, Zheng Rong, Jia Xin Zhuang, and Liang Zhu Wang. "The Application of SWMM in the Analysis of a Campus Drainage System." Applied Mechanics and Materials 744-746 (March 2015): 1146–50. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.1146.
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The drainage system of a part of a university campus was tapped using SWMM (Storm Water Management Model). Local drainage discharge capacity was studied under different design storm return period. Results show that flooding and overload at some junctions and in some conduits are doubled with the increase of design rain return period from one year to five year, which may deteriorate the traffic and road base.
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Arsana, I. Nengah, Irianto Irianto, and Baiq Kisnawati. "ANALISIS PENGARUH FAKTOR-FAKTOR BASE LENDING RATE TERHADAP RETURN ON EQUITY PADA KSP. MADANI NTB." Jurnal Aplikasi Akuntansi 2, no. 2 (October 12, 2018): 032–58. http://dx.doi.org/10.29303/jaa.v2i2.23.
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This study entitled "Analysis of the Effects of Base Lending Rate Factors on Return On Equity On KSP. Madani NTB ". This study aims to measure the effect of partial and simultaneous variables factors Base Lending Rate (Cost of Laonable Fund, Overhead Cost, Risk Cost, Tax Rate) on Return On Equity on KSP. Madani NTB and analyze the variable Cost of Laonable Fund, Overhead Cost, Risk Cost, Tax Rate is the most dominant and significantly affect the Return On Equity on KSP. Madani NTB.
The type of research used in this study is associative research. Data collection techniques conducted in this study are observation, interview and documentation. The type of data used is quantitative data. The procedure of data analysis using multiple regression model analysis.
The results of this study indicate that the Cost of Laonable Fund, Overhead Cost, Risk Cost, Tax Rate is not entirely partially have a significant effect on Return on Equity on KSP.Madani NTB, caused by 1 (one) variable Tax Rate partially has no influence significant to the Return on Equity variable (Y), and all independent variables (Cost of Laonable Fund, Overhead Cost, Risk Cost, Tax Rate) simultaneously give a significant influence on the Return on Equity variable (Y). In addition, Risk Cost variable has the most dominant influence on Return on Equity in KSP.Madani NTB.
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Petropoulos, Theofanis, Konstantinos Liapis, and Eleftherios Thalassinos. "Optimal Structure of Real Estate Portfolio Using EVA: A Stochastic Markowitz Model Using Data from Greek Real Estate Market." Risks 11, no. 2 (February 12, 2023): 43. http://dx.doi.org/10.3390/risks11020043.
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The purpose of this paper is to examine the issue of portfolio optimization. Optimization consists of minimizing the risk for a given rate of return or achieving a bigger return for a given level of risk. We use historical data from the Bank of Greece to calculate the net return and the standard deviation (std) for each type of property that is available. The objective is to maximize the economic value added (EVA) of a property’s assets portfolio under a specific rate of standard deviation, following the classic Markowitz model (M-V). The stochastic procedure entry in the model uses the Monte Carlo Simulation method with debt to equity (DTE) following PERT distribution for the portfolio’s invested budget, and the net return for the normal distribution with the mean of the expected return and std are taken from historical data, correspondingly. The returns verify that they follow the base assumption of normality through the Lilliefors test in the Greek real estate market. We observe the maximization of EVA and the expected return maximizing concurrently, but the minimizing risk of EVA is diversified with the minimization of portfolio risk. We observe that the max weight that a residential asset takes is 22.7% because a bigger percent reduces both mean and std. The study provides an explicit portfolio optimization procedure under uncertainty in the real estate market and enriches the academic debate about EVA and revenue.
Books on the topic "Return-to-base model"
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Kagen, Melissa. Wandering Games. The MIT Press, 2022. http://dx.doi.org/10.7551/mitpress/13856.001.0001.
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An analysis of wandering within different game worlds, viewed through the lenses of work, colonialism, gender, and death. Wandering in games can be a theme, a formal mode, an aesthetic metaphor, or a player action. It can mean walking, escaping, traversing, meandering, or returning. In this book, game studies scholar Melissa Kagen introduces the concept of “wandering games,” exploring the uses of wandering in a variety of game worlds. She shows how the much-derided Walking Simulator—a term that began as an insult, a denigration of games that are less violent, less task-oriented, or less difficult to complete—semi-accidentally tapped into something brilliant: the vast heritage and intellectual history of the concept of walking in fiction, philosophy, pilgrimage, performance, and protest. Kagen examines wandering in a series of games that vary widely in terms of genre, mechanics, themes, player base, studio size, and funding, giving close readings to Return of the Obra Dinn, Eastshade, Ritual of the Moon, 80 Days, Heaven's Vault, Death Stranding, and The Last of Us Part II. Exploring the connotations of wandering within these different game worlds, she considers how ideologies of work, gender, colonialism, and death inflect the ways we wander through digital spaces. Overlapping and intersecting, each provides a multifaceted lens through which to understand what wandering does, lacks, implies, and offers. Kagen's account will attune game designers, players, and scholars to the myriad possibilities of the wandering ludic body.
Book chapters on the topic "Return-to-base model"
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Heidler, Fridolin. "Return Stroke Process Simulation Using TCS Model." In Electromagnetic Compatibility [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98898.
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The Traveling Current Source (TCS) model describes the electrical processes during the lightning return stroke phase. The TCS model assumes that the lightning current is injected at the top of the increasing return stroke channel represented by a transmission line. The electric and magnetic field is calculated based on the spatial and temporal distribution of the lightning current along the return stroke channel. It is shown that the main characteristics of the measured electric and magnetic fields can be reproduced with the TCS model. These are the Initial Peak of the electric and magnetic fields for near intermediate and far distances, the Ramp (up to the maximum) of the near electric field, the Hump of the near magnetic field after the initial peak, and the Zero Crossing of the far distant electric and magnetic fields. The fundamentals of the model are presented, and the model is extended to consider the current reflections occurring at the ground and the upper end of the return stroke channel. To this end, the ground reflection factor ρ and the top reflection factor R are introduced. Due to the increasing return stroke channel, the top reflection factor is a function of the return stroke velocity. The total current is composed of the source current according to the TCS model and the reflected currents. It is shown that the ground reflection causes significant variation in the waveform of the channel-base current and the electric and magnetic fields.
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Li, Shuang, and Jun Sasaki. "A Kansei Model of One-Day Circular Tour Considering Satisfaction and Tired Condition of Transportation." In Knowledge Innovation Through Intelligent Software Methodologies, Tools and Techniques. IOS Press, 2020. http://dx.doi.org/10.3233/faia200580.
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The number of Foreign Independent Tour (FIT) is increasing rapidly in the world. The FIT tourists usually leave from one hotel as a base, travel around multiple sightseeing areas and return to the same hotel by using some public transportation methods in one day (we call it “one-day circular tour (OCT)”). However, due to the restriction on the public transport schedule, it is difficult to travel around multiple sightseeing areas efficiently with high satisfaction within a limited time. In our previous research, we proposed a planning algorithm for OCT to obtain high satisfaction using such public transportations. But, the satisfaction and tired condition of transportation was not considered there. In this paper, we propose a Kansei model for OCT including the satisfaction and tired condition of transportation and shows the evaluation results in a case study using persona method on travelers in Iwate Prefecture, Japan.
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Shukla, Jagrat, Numburi Rishikha, Janhavi Chaturvedi, Sumathi Gokulanathan, Sriharipriya Krishnan Chandrasekaran, Konguvel Elango, and SathishKumar Selvaperumal. "Strategies for Automated Bike-Sharing Systems Leveraging ML and VLSI Approaches." In Advances in Systems Analysis, Software Engineering, and High Performance Computing, 172–203. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6596-7.ch007.
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Machine learning has had an impact in the area of microchip design and was initially used in automation. This development could result in a tremendous change in the realm of hardware computation and AI's powerful analysis tools. Traffic is a pressing issue in densely populated cities. Governments worldwide are attempting to address this problem by introducing various forms of public transportation, including metro. However, these solutions require significant investment and implementation time. Despite the high cost and inherent flaws of the system, many people still prefer to use their personal vehicles rather than public transportation. To address this issue, the authors propose a bike-sharing solution in which all processes from membership registration to bike rental and return are automated. Bagging is an ensemble learning method that can be used for base models with a low bias and high variance. It uses randomization of the dataset to reduce the variance of the base models, while keeping the bias low.
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Aronczyk, Melissa, and Maria I. Espinoza. "Conclusion." In A Strategic Nature, 210–17. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780190055349.003.0009.
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The conclusion, We’re Supposed to Be Engaging, acknowledges that public relations creates, shapes and promotes a politics that is embedded in our major institutions, our common practices of mediated debate, and the way we collectively think about what “the public” is and what it ought to do. This conception of democratic politics is so deeply engrained in our habits of action that even when we fight for better representation of those voices that are continually left unheard or denied participation or the right to engage, we retain its premises instead of attempting to challenge it at its base. Rather than turn to publicity to inform, engage, and mobilize, we call for a return to the authority of scientific models of inquiry in the fields of culture and politics.
Conference papers on the topic "Return-to-base model"
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Laface, Valentina, Elzbieta M. Bitner-Gregersen, Felice Arena, and Alessandra Romolo. "A Parameterization of DNV GL Storm Profile for Long-Term Analysis of Ocean Storms: Trapezoidal Storm Model." In ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-95880.
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Abstract The paper introduces a parameterization of the DNV GL storm profile for developing an analytical model for calculations of the return period of a storm whose peak exceeds a given threshold. The DNV GL storm evolution is represented via an isosceles trapezoidal shape in which the minor base represents the storm peak duration, the major base the total storm duration and the height is half of the highest significant wave height in the actual storm. In this representation, the storm duration is not related to the storm intensity and it is fixed constant and equal to 42 hours, while the peak duration is assumed to be 6 hours. The parameterization proposed in the paper consists in expressing the peak duration as a fraction of the total storm duration allowing to investigate the effects of storm peak duration on long term estimates. The analytical solution for the return period is derived by following the classical approach of Equivalent Storm Models that is referring to the equivalent storm sequence, with the only difference that all the Trapezoidal Storm durations are identical whatever the storm intensity is. This assumption leads to significant simplification on the model development and potential employment as well. Further, a closed form solution is achieved for the return period which is also a generalization of the triangular shape. Finally, data analysis with NDBC buoys data is carried out for validating the model and elucidating analogies and differences with respect to classical Equivalent Storm approach. Results have shown that the Trapezoidal Model can be thought as a triangular one with a prudential factor on the storm peak duration which results in a reasonable overestimation of maximum expected wave height and return values.
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Dong, Sheng, and Jinjin Ning. "Applications of a Compound Distribution on Estimating Wind and Wave Parameters for Fixed Platforms Design." In 25th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/omae2006-92189.
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Based on the hindcast data of 21 storm processes, a Poisson bivariate Logistic extreme value distribution is proposed to estimate the joint probability of extreme wind speed and extreme significant wave height in the storms, the frequency of which can be described by a Poisson distribution. In order to calculate the structural response of an ocean platform, such as base shear, three methods are utilized, namely (I) traditional univariate frequency analysis method; (II) base shear return value method; (III) wind-wave joint probability method. Calculation results show that the proposed statistical model is suitable for the design of fixed platforms in the storm-influenced area.
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Ponce de León, Sonia, João H. Bettencourt, Joseph Brennan, and Frederic Dias. "Evolution of the Extreme Wave Region in the North Atlantic Using a 23 Year Hindcast." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41438.
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The IOWAGA data base for the North Atlantic region was used to identify the region where extreme values of significant wave height are more likely to occur. The IOWAGA database [1] was obtained from the WAVEWATCH III model [2] hindcast using the CFSR (Climate Forecast System Reanalysis) from NOAA [3,4]. The period of the study covers 1990 up to 2012 (23 years). The variability of the significant wave height was assessed by computing return periods for sea storms where the significant wave height exceeds a given threshold. The return periods of sea storms where the Hs exceeds extreme values for the north Atlantic region were computed allowing for the identification of the extreme wave regions which show that extreme waves are more likely to occur in the storm track regions of the tropical and extratropical north Atlantic cyclones.
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Tao, Shanshan, Sheng Dong, and Yinghui Xu. "Design Parameter Estimation of Wave Height and Wind Speed With Bivariate Copulas." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-10519.
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The data of annual extreme wave height and corresponding wind speed at a platform in Bohai Bay is hindcasted by a numerical model from 1970 to 1993. Common-used design probability distributions, such as Gumbel distribution, Weibull distribution, and lognormal distribution are applied to fit the data of extreme wave height and concomitant wind speed, respectively. Then the best-fitted marginal distributions of annual extreme wave height and wind speed can be selected. Bivariate normal copula and Frank copula are utilized to construct joint distribution of these two random variables. Based on empirical base shear equation of the on-site fixed jacket platform, the maximum base shear can be calculated under the same joint return period of the wave height and wind speed. The results show that the proposed joint probability models constructed by bivariate copulas result in lower the design environmental parameters because of the consideration of correlation between random variables. Eventually the investment cost of marginal oil fields could be relatively reduced.
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Bush, Erica, and Lance Manuel. "The Influence of Foundation Modeling Assumptions on Long-Term Load Prediction for Offshore Wind Turbines." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80050.
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The objective of this study is to investigate the effect of alternative monopile foundation models for shallow-water offshore wind turbines on extreme loads associated with 20-year return periods. Foundation models with tower base fixed at the mudline, with apparent fixity points below the mudline, with coupled transverse and lateral springs at the mudline, and with distributed springs over the entire penetration depth of the monopile are compared. We employ a utility-scale 5 MW offshore wind turbine model with a 90-meter hub height in stochastic simulations; the turbine is sited in 20 meters of water. Selected 20-year wind speed and wave height combinations are employed as we study comparative response statistics, power spectra, and probability distributions of extreme loads for the fixed-base and the three different flexible foundation models. A discussion on the varying dynamics, on short-term response statistics, and on extrapolated long-term loads from limited simulation is presented. Sea states involving wind speeds close to the turbine’s rated wind speed are found to control 20-year loads, and the flexible foundation models are found to experience higher extreme loads than the fixed-based case. Overall, the three flexible foundation models appear to yield similar long-term loads based on an Inverse FORM (First-Order Reliability Method) approach for the selected turbine and soil profile used in this study.
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Gainer, John J., Levi D. DeVries, and Michael D. Kutzer. "Persistent Target Detection and Tracking by an Autonomous Swarm." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85573.
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This paper presents an autonomous multivehicle control algorithm capable of persistently searching and tracking targets in a defined search area subject to operational endurance constraints of individual agents. The algorithm development is modular to allow scalability and a control architecture that can be modified to any type of autonomous vehicle, search area, or target. In practical application, a target can be anything from heat signatures to radioactive material; therefore, this work employs a generic emitter-detector pair as a placeholder relationship for real world applications. The control strategy accounts for the appearance, motion, and disappearance of multiple targets in the search space constituting the utility of creating a team of multiple search agents. When agent battery level drops below a predetermined threshold, the agent returns to a base station to recharge and be relaunched into the mission. Remaining agents must account for this loss and gain of other team members as they exit the search environment. The contributions of this work are 1) the design of search trajectories for autonomous vehicles with limited endurance, 2) incorporation of return-to-base and recharge time requirements, and 3) coordination of multiple vehicles by developing a decision-making model to and assign agents to operational modes. We have run an extensive number of experimental trials to collect and analyze performance data for further development and testing.
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Newborn, David, Nels Sultan, Pierre Beynet, Tim Maddux, Sungwon Shin, and Dan Cox. "Experimental Observations and Numerical Simulations of Wave Impact Forces on Recurved Parapets Mounted Above a Vertical Wall." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79183.
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Large-scale hydraulic model tests and detail numerical model investigations were conducted on recurved wave deflecting structures to aid in the design of wave overtopping mitigation for vertical walls in shallow water. The incident wave and storm surge conditions were characteristic return period events for an offshore island on the North Slope of Alaska. During large storm events, despite depth-limited wave heights, a proposed vertical wall extension was susceptible to wave overtopping, which could potentially cause damage to equipment. Numeric calculations were conducted prior to the experimental tests and were used to establish the relative effectiveness of several recurved parapet concepts. The numerical simulations utilized the COrnell BReaking waves and Structures (COBRAS) fluid modeling program, which is a Volume-of-Fluid (VOF) model based on Reynolds Averaged Navier-Stokes equations [1] [2]. The experimental testing was conducted in the Large Wave Flume (LWF) at Oregon State University, O.H. Hinsdale Wave Research Laboratory. The experimental test directly measured the base shear force, vertical force, and overturning moment applied to the recurved parapets due to wave forcing. Wave impact pressure on the parapet and water particle velocities seaward of the wall were also measured. Results from the experimental testing include probability of exceedance curves for the base shear force, vertical force, and overturning moment for each storm condition. Qualitative comparisons between the experimental tests and the COBRAS simulations show that the numerical model provides realistic flow on and over the parapet.
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Lim, Choong Heng, Temmy Harianto Dharmadji, Azrin Kassim, Muhammad Usman Ul Haq Sethi, and Muhammad Kamran Qureshi. "Competitive Evaluation of Malaysia Enhanced Profitability Terms with Southeast Asia Fiscal Terms." In International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-22162-ms.
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Abstract Malaysia has introduced a shallow-water enhanced profitability term (EPT) production sharing contract (PSC) in the year 2021 to reward a PSC contractor with equitable returns reflecting the business risk and the opportunity to accelerate development and monetization. This study evaluates the attractiveness of the EPT against several fiscal terms adopted in southeast Asia, including Indonesia, Vietnam, Thailand, and Myanmar. This paper established an offshore shallow-water field development analogue project with a total production volume of 68 MMbbl, capital expenditure (Capex) of USD 530 million, predevelopment operating expenditure (Opex) of USD 36 million, variable Opex of USD 12.5/bbl, floating production storage and offloading (FPSO) rental of USD 61 million/year, and abandonment capital of USD 101 million. High, base, and low scenarios are considered for oil price per barrel as USD 70, 60, and 50, respectively, and production volume scenarios as 78, 68, and 58 MMbbl, respectively. These values with certain fiscal assumptions are input into a fiscal model engine for economic indicators [net present value (NPV), rate of return (ROR), and payback], revenue take, after-tax cashflow, and variables sensitivity calculations to evaluate base, optimistic, and pessimistic cases. In the base case, the attractiveness order of countries based on a higher-positive NPV at 10% and ROR are Malaysia EPT (NPV at 10% = USD 198 million, ROR = 30.4%), Indonesia PSC (2017) (NPV at 10% = USD 149 million, ROR = 28.3%), and Thailand Royalty and Tax (R/T; 1991) (NPV at 10% = USD 32 million, ROR = 14.5%). In the optimistic case, the NPVs at 10% are improved, ranging from Thailand (+271%), Myanmar (+247%), Malaysia (+151%), and Indonesia and Vietnam (+141%) as compared to the base case. In the pessimistic case, all the fiscal terms are unfeasible for ROR at 10%. Myanmar PSC (1993) yields above 10% ROR only when the production is at the base or high scenario with oil price at USD 70/bbl. Vietnam PSC (2013) is unfeasible for positive NPV at 10% even with high oil price under various taxes, including the windfall profit tax. Indonesia has a better NPV at 10% at a low oil price because of the progressive split that subsidizes the operator. Oil price and production volume are the top two sensitive variables except for Vietnam, where capital is the highest. The contractor take is higher in Malaysia, followed by Indonesia, Thailand, Myanmar, and Vietnam at base and high oil price. When the oil price is low, Indonesia generated a higher contractor take than Malaysia. Malaysia EPT is the only fiscal regime that can generate a contractor take that is higher than government take and stagnant around 55% against the 40% in Indonesia. In conclusion, Malaysia EPT provides a better investment return when the oil price is USD 60/bbl and above, while Indonesia gross split is more profitable when the oil price is low. This study provides insights on the potential investment returns by new EPT fiscal terms. The attractiveness and potential margin upside when the oil price is on the rebound paves the way for other southeast Asia fiscal terms.
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Sequeiros, Octavio, and Sergio Jaramillo. "Extreme Coastal Inundation Under Different Climate Scenarios: Fourchon Junction Case Study." In Offshore Technology Conference. OTC, 2021. http://dx.doi.org/10.4043/30940-ms.
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Abstract Port Fourchon Junction is located within Chevron's Fourchon Terminal, just south of Port Fourchon and is operated by Shell Pipeline Company LP. This manifold metering station is a critical junction for the Mars Corridor oil, as oil production from Mars (MC-807), Ursa (MC-809), Titan (MC-941), Who Dat (MC-547), Medusa (MC-582), and Olympus (MC-807B) flows through this station via a 24" pipeline. Port Fourchon is at the edge of the Mississippi delta facing the sea, one of the world's most vulnerable low-elevation coastal zones. It is highly exposed to storm surge and wave-induced inundation under hurricanes which regularly visit the Gulf of Mexico. In addition, it experiences one of the largest rates of subsidence in the world, which combined with sea level rise, will increase the site vulnerability in the coming decades. This study assesses present and future scenarios of subsidence and sea level rise under extreme metocean conditions induced by hurricanes and their impact on Port Fourchon Junction. Local effects such as the differential settlement of the barrier beach have been also considered. Using results from the numerical model XBeach, a set of different present and future scenarios are modelled under extreme metocean conditions. These conditions and the subsequent design parameters calculated, are not obtained through traditional extreme value analysis methods, instead, they are estimated through the influence of boundary conditions forced with the corresponding return period values of the parameters. Boundary conditions for the simulations are extracted from Grand Isle and Port Fourchon sea level observations, and from FEMA and the Water Institute of the Gulf simulations. Port Fourchon site should be subject to flooding for 10-year return period conditions based on Grand Isle observations. For 5-6 years return period conditions some degree of milder partial flood should also be expected. This is well captured by the model. While the highest inundating level is mostly dependent on winds, waves and surge acting together, surge is the single most critical parameter that defines the asset's base inundation level. Design future conditions based on surge extreme from FEMA simulations are recommended over surge extremes derived from Grand Isle observations. The barrier beach and the breakwaters play a key factor in sheltering site from waves and surge. Even when submerged under extreme high return period conditions they dissipate the waves ensuring that the maximum water level (wave crest elevation) on site is lower than would otherwise be without them. It is then important to maintain them fit for purpose during the entire lifespan of the asset. Both Grand Isle and Port Fourchon subsidence scenarios yield similar results. Based on the importance of Port Fourchon Junction facilities, the design criteria obtained, and the higher subsidence level observed at Port Fourchon (compared to Grand Isle), it is recommended that a 1000-year return period and future scenario based on FEMA surge level and Port Fourchon Relative Sea Level Rise (RSLR) is adopted for design. The subsidence associated to this scenario is 9.8 mm/year. The sea level rise associated to this scenario is 2 mm/year.
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Sheng, Chenguang, George Nnanna, and Chandramouli Viswanathan. "Lake Michigan Water Resources Study." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38369.
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This paper contains an analysis of withdrawal data for North West Indiana to compute consumptive-use coefficients and to describe monthly variability of withdrawals and consumptive use. Concurrent data were available for most water-use categories from 1990 through 2008. Average monthly water withdrawals are discussed for a variety of water-use categories, and average water use per month is depicted graphically. Water quality analysis is presented and historic water quality data of Northwest Indiana, (Lake, Porter and LaPort Counties) were downloaded from USEPA website and they were examined for the trends in different water quality constituents. Individual station based analysis and regional analysis were conducted using MK Test. Water quality data indicated an improvement trend. Water withdrawals data were analyzed using regression and Artificial Neural Network (ANN) models. The ANN model performed a better forecasting while compared to a linear regression model. For most water-use categories, the summer months were those of highest withdrawal and highest consumptive use. For public supply, average monthly withdrawals ranged from 2,193 million gallons per day (Mgal/d) (February) to 3,092 Mgal/d (July). North West Indiana energy production had large increases in average monthly withdrawals in the summer months (17,551 Mgal/d in February to 26,236 Mgal/d in July, possibly because of increased electricity production in the summer, a need for additional cooling-water withdrawals when intake-water temperature is high, or use of different types of cooling methods during different times of the year. Average industrial withdrawals ranged from 31,553 Mgal/d (February) to 36,934 Mgal/d (August). The North West Indiana irrigation data showed that most withdrawals were in May through October for golf courses, nurseries, and crop irrigation. Miscellaneous water withdrawals ranged from 12.2 Mgal/d (January) to 416.3 Mgal/d (October), commercial facilities that have high water demand in Indiana are medical facilities, schools, amusement facilities, wildlife facilities, large stores, colleges, correctional institutions, and national security facilities. Consumptive use and consumptive-use coefficients were computed by two principal methods in this study: the return-flow and withdrawal method and the winter-base-rate method (WBR). The WBR method was not suitable for the industrial and miscellaneous water-use categories. The RW method was not used for public-supply facilities. The public-supply annual average consumptive-use coefficient derived by use of the WBR methods is 8 percent from 1990 to 2008 for North West Indiana; the summer average consumptive-use coefficient was considerably higher with the amount of 20 percent. The energy production annual consumptive-use coefficient was 13 percent by the WBR method, which increased to 28 percent for summer. In terms of maximum accuracy and minimal uncertainty, use of available withdrawal, return-flow, and consumptive-use data reported by facilities and data estimated from similar facilities are preferable over estimates based on data for a particular water-use category or groups of water-use categories. If monthly withdrawal, return flow, and consumptive use data are few and limited, monthly patterns described in this report may be used as a basis of estimation, but the level of uncertainty may be a greater than for the other estimation methods.
Reports on the topic "Return-to-base model"
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Gouel, Christophe, and Thomas Hertel. Introducing Forest Access Cost Functions into a General Equilibrium Model. GTAP Research Memoranda, November 2006. http://dx.doi.org/10.21642/gtap.rm08.
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Abstract The purpose of this Research Memorandum is to propose an approach to incorporating forest access cost functions into global general equilibrium models such as GTAP. Towards this end, we develop a long run access cost function which can be calibrated to national data on total forest land, currently inaccessible forest land, forest land rents, and expected rates of return on investment. This is illustrated for an 11 region aggregation of the GTAP-AEZ data base. We find that this long run function generates far too high a rate of annual access, and so we introduce a short run component which introduces a quadratic term into the cost function. This can be chosen to target current rates of forest access as reported by the FAO. Finally, we discuss the treatment of this new type of investment in the general equilibrium model. Keywords: Deforestation, inaccessible forests, cost function, investment. JEL codes: Q23, Q24, Q27