با سلام خدمت کاربران عزیز، به اطلاع می رساند ترجمه مقالاتی که سال انتشار آن ها زیر 2008 می باشد رایگان بوده و میتوانید با وارد شدن در صفحه جزییات مقاله به رایگان ترجمه را دانلود نمایید.
Zero-net energy management for the monitoring and control of dynamically-partitioned smart water systems
مدیریت انرژی صفر خالص برای نظارت و کنترل سیستم های اب هوشمند تقسیم شده -2020
The optimal and sustainable management of water distribution systems still represent an arduous task. In many instances, especially in aging water net-works, pressure management is imperative for reducing breakages and leakages. Therefore, optimal District Metered Areas represent an effective solution to decreasing the overall energy input without performance compromise. Within this context, this paper proposes a novel adaptive management framework for water distribution systems by reconfiguring the original network layout into (dynamic) district metered areas. It utilises a multiscale clustering algorithm to schedule district aggregation/desegregation, whilst delivering energy and supply management goals. The resulting framework was tested in a water utility network for the simultaneously production of energy during the day (by means of the installation of micro-hydropower systems) and for the reduction of water leakage during the night. From computational viewpoint, this was found to significantly reduce the time and complexity during the clustering and the dividing phase. In addition, in this case, a recovered energy potential of 19 MWh per year and leakage reduction of up to 16% was found. The addition of pump-as-turbines was also found to reduce investment and maintenance costs, giving improved reliability to the monitoring stations. The financial analyses to define the optimal period in which to invest also showed the economic feasibility of the proposed solution, which assures, in the analysed case study, a positive annual net income in just five years. This study demonstrates that the combined optimisation, energy recovery and creation of optimized multiple-task district stations lead to an efficient, resilient, sustainable, and low-cost management strategy for water distribution networks.
Keywords: Water distribution systems | Micro-hydropower systems | Sustainable and smart cities | Water-energy nexus | Water leakage reduction | Financial return-on-investment
Factors influencing the adoption of mHealth services in a developing country: A patient-centric study
عوامل مؤثر بر اتخاذ خدمات بهداشتی و درمانی در یک کشور در حال توسعه: یک مطالعه بیمار محور-2020
mHealth under the umbrella of eHealth has become an essential tool for providing quality, accessible and equal health care services at an affordable cost. Despite the potential benefits of mHealth, its adoption remains a big challenge in developing countries such as Bangladesh. This study aims to examine the factors affecting the adoption of mHealth services in Bangladesh by using the extended Unified Theory of Acceptance and Use of Technology (UTAUT) model with perceived reliability and price value factors. It also examines the moderating effect of gender on the intention to use and on the actual usage behavior of users of mHealth services. A wellstructured face-to-face survey was employed to collect the data. Structural equation modeling (SEM) with a partial least squares method was used to analyze the data collected from 296 generation Y participants. The results confirmed that performance expectancy, social influence, facilitating conditions and perceived reliability positively influence the behavioral intention to adopt mHealth services. However, effort expectancy and price value did not have a significance influence on the behavioral intention. Moreover, Gender has a significant moderating effect on mHealth services adoption in certain cases. Finally, the theoretical and practical implications of this study are also discussed.
Keywords: mHealth | Developing countries | UTAUT model | Generation Y | Bangladesh
Online adaptive water management fault diagnosis of PEMFC based on orthogonal linear discriminant analysis and relevance vector machine
تشخیص خطای مدیریت آب انطباقی آنلاین PEMFC بر اساس تجزیه و تحلیل تمایز خطی متعامد و دستگاه بردار ارتباط-2020
A data-driven strategy for characterizing the water management failure in a Proton Exchange Membrane Fuel Cell (PEMFC) is presented in this paper. To carry out the diagnosis of water management failure, first the original single cell voltages are projected into lowerdimension features by applying orthogonal linear discriminant analysis (OLDA). Then, a classification methodology termed relevance vector machine (RVM) is employed to classify the lower-dimension features into different categories that indicate the respective health states of the system. The initially trained projecting vectors and classifiers lose their efficiency gradually the characteristics of PEMFC system change, such as the cell voltages decaying with time due to the normal degradation due to aging. An online adaptive diagnostic strategy based on the posterior probability of RVM is proposed, so as to keep the diagnostic accuracy over time. The efficiency and reliability of this online adaptive diagnostic strategy is validated using an experimental database from a 90-cell PEMFC stack.
Keywords: Proton exchange membrane fuel cell | (PEMFC) | Orthogonal linear discriminant | analysis (OLDA) | Relevance vector machine (RVM) | Water management failure | Online adaptive diagnostics
A contingency based energy management strategy for multi-microgrids considering battery energy storage systems and electric vehicles
یک استراتژی مدیریت انرژی مبتنی بر شرایط احتمالی برای چند میکروگرید با توجه به سیستم های ذخیره انرژی باتری و وسایل نقلیه الکتریکی-2020
The emergence of microgrids along with extending the use of new energy resources, energy storage systems and electric vehicles at distribution level has changed traditional distribution systems into multi-microgrids (MMGs) which are usually more stable and reliable. For an MMG system, the probability of a fault occurrence at each time period makes the system operation process more complex. From this point of view, this paper aims at proposing a coordinated energy management strategy for optimal operation of MMG systems using a variable weighted multi-objective function. Based on this method, in the case of occurrence of a contingency problem, multiple operators are able to change the weight of functions depending on contingencies and are responsible for the proper use of energy storage systems and other distributed energy resources. Moreover, an efficient optimization algorithm called targeted search shuffled complex evolution is proposed to quickly optimize decision parameters during faulted and normal operation modes. Finally, a unified framework is presented to implement the proposed energy management strategy along with the reliability study of the intended test system, and the ability of the proposed approach is investigated in a modified reliability-based case study by considering different scenarios
Keywords: Energy management strategy | Energy storage systems | Electric vehicles (EVs) | Multi-microgrid (MMG) | Optimization | Shuffled complex evolution
Z-number based earned value management (ZEVM): A novel pragmatic contribution towards a possibilistic cost-duration assessment
مدیریت ارزش به دست آمده مبتنی بر عدد Z (ZEVM): سهم عملگرا جدید نسبت به ارزیابی هزینه تمام شده احتمالی-2020
The Earned value management (EVM) is one of the simplified analytical cost-duration assessment tools which assist project managers in monitoring the status of the project undertaken. The EVM has been elaborated by both deterministic and uncertain numbers such as fuzzy logic in the light of time. Even though cost-duration analysis is so sensitive and fluctuating in projects, the adopted approaches were unable to consider the conspicuous unreliability which is always involving the decision-making data. This problem impedes project managers to trust the foreseen inferences. To help in overcoming this critical deficiency, Z-numbers were proposed to take possibilities and reliabilities into account. Applying Z-numbers and possibilistic modeling in the EVM is a challenging topic which causes the accuracy of cost-duration tracing results to be significantly enhanced. This paper presents the application of z-numbers for modeling the earned value indicators and proves the superiority of the ZEVM against traditional fuzzy EVM. This work originally adds to the state-of-the-art literature on earned value management by presenting a proposal and applications of a new as Z-Earned Value Management (ZEVM). An illustrative case is resolved to magnify the capability of the proposed framework in dealing with higher levels of uncertainty associated with decision-making data.
Keywords: Earned value management | Fuzzy sets | Project evaluation | Uncertainty | Z-number
الگوریتم تکاملی چند هدفه مبتنی بر شبکه عصبی برای زمانبندی گردش کار پویا در محاسبات ابری
سال انتشار: 2020 - تعداد صفحات فایل pdf انگلیسی: 16 - تعداد صفحات فایل doc فارسی: 45
زمانبندی گردشکار یک موضوع پژوهشی است که به طور گسترده در محاسبات ابری مورد مطالعه قرار گرفته است و از منابع ابری برای کارهای گردش کار استفاده می¬شود و برای این منظور اهداف مشخص شده در QoS را لحاظ می¬کند. در این مقاله، مسئله زمانبندی گردش کار پویا را به عنوان یک مسئله بهینه سازی چند هدفه پویا (DMOP) مدل می¬کنیم که در آن منبع پویایی سازی بر اساس خرابی منابع و تعداد اهداف است که ممکن است با گذر زمان تغییر کنند. خطاهای نرم افزاری و یا نقص سخت افزاری ممکن است باعث ایجاد پویایی نوع اول شوند. از سوی دیگر مواجهه با سناریوهای زندگی واقعی در محاسبات ابری ممکن است تعداد اهداف را در طی اجرای گردش کار تغییر دهد. در این مطالعه یک الگوریتم تکاملی چند هدفه پویا مبتنی بر پیش بینی را به نام الگوریتم NN-DNSGA-II ارائه می¬دهیم و برای این منظور شبکه عصبی مصنوعی را با الگوریتم NGSA-II ترکیب می¬کنیم. علاوه بر این پنج الگوریتم پویای مبتنی بر غیرپیش بینی از ادبیات موضوعی برای مسئله زمانبندی گردش کار پویا ارائه می¬شوند. راه¬حل¬های زمانبندی با در نظر گرفتن شش هدف یافت می¬شوند: حداقل سازی هزینه ساخت، انرژی و درجه عدم تعادل و حداکثر سازی قابلیت اطمینان و کاربرد. مطالعات تجربی مبتنی بر کاربردهای دنیای واقعی از سیستم مدیریت گردش کار Pegasus نشان می¬دهد که الگوریتم NN-DNSGA-II ما به طور قابل توجهی از الگوریتم¬های جایگزین خود در بیشتر موارد بهتر کار می¬کند با توجه به معیارهایی که برای DMOP با مورد واقعی پارتو بهینه در نظر گرفته می¬شود از جمله تعداد راه¬حل¬های غیرغالب، فاصله¬گذاری Schott و شاخص Hypervolume.
|مقاله ترجمه شده|
An efficient interactive framework for improving resilience of power-water distribution systems with multiple privately-owned microgrids
یک چارچوب تعاملی کارآمد برای بهبود مقاومت در برابر سیستم های توزیع آب و انرژی با چندین میکروگرید متعلق به بخش خصوصی-2020
Resilience improvement of power distribution networks against natural disasters is an important problem. Water network similar to other important infrastructures depends on power networks. In this paper, resilience improvement is defined as increasing the users’ accessibility to water and power after natural disasters. Microgrids with appropriate operation can provide energy to restore disconnected loads in distribution networks. In the proposed interactive framework, a stochastic energy management program for microgrids is designed that not only determines the amount of energy can be delivered to distribution systems, but also considers the reliability of local loads during emergency conditions. Each microgrid provides a list of bid-quantity energy blocks to the distribution system operator (DSO) during the emergency period. Then, the DSO chooses the best plan to restore disconnected loads considering inaccessibility values to power and water and also the damage of power and water distribution networks. Demand response actions in microgrids are also considered as effective tools for the energy management program, and their impact on the distribution system resilience is investigated. The proposed model is tested on the modified IEEE 33-bus distribution system with multiple microgrids, and the effectiveness of the proposed method is validated accordingly.
Keywords: Microgrids | Natural disasters | Resilience | Stochastic linear programming | Water network
Energy management in multi-microgrids considering point of common coupling constraint
مدیریت انرژی در چند میکروگرید با توجه به محدودیت اتصال مشترک-2020
There are different models for Energy Management of Multi-Microgrids (MMGs). Generally, the owners of microgrids are not identical. In this case, due to privacy concerns and overcomes drawbacks of conventional decentralized systems, hybrid energy management system is proposed. Unlike other energy management models, in hybrid model, multi-microgrids are connected to the grid through the common line entitled Point of Common Coupling (PCC). Energy management in hybrid multi-microgrids considering optimal utilization of PCC capacity is a critical issue that has been less taken into account. In this paper, a new bi-level method is proposed for optimal energy management in hybrid MMG systems taking into account the PCC line capacity. In the first level, each microgrid implements its day-ahead scheduling based on different quantities of PCC line capacity and extracts its profit-quantity curve. This novel curve shows the variations of microgrid profits versus different PCC limits. Subsequently, a two-stage optimization problem is presented in the second level, in which in the first stage an introduced microgrid aggregator (MGA) maximizes microgrids aggregated profit and determines optimal quota of each microgrid from PCC line based on corresponding profit-quantity curves while in the second stage, this profit is fairly divided among microgrids via Shapely value. Numerical results demonstrate the efficiency and reliability of the proposed method.
Keywords: Energy management | Multi microgrid | Aggregator | Congestion | Common line
Average rates of return, working capital, and NPV-consistency in project appraisal: A sensitivity analysis approach
میانگین نرخ بازده ، سرمایه در گردش و سازگاری NPV در ارزیابی پروژه: یک رویکرد تحلیل حساسیت-2020
In project appraisal under uncertainty, the economic reliability of a measure of financial efficiency such as a rate of return depends on its strong NPV-consistency, meaning that the performance metric (i) supplies the same recommendation in accept–reject decisions as the NPV, (ii) ranks competing projects in the same way as the NPV, (iii) has the same sensitivity to perturbations in the input data as the NPV. In real-life projects, financial efficiency is greatly affected by the management of the working capital. Using a sensitivity analysis approach and taking into explicit account the role of working capital, we show that the average return on investment (ROI) is not strongly NPV-consistent in accept–reject decisions if the working capital is uncertain and changes under changes in revenues and costs. Also, it is not strongly NPV-consistent in project ranking. We also show that the internal rate of return (IRR) is not strongly NPV-consistent and economic analysis may even turn out to be impossible, owing to possible nonexistence and multiplicity caused by perturbations in the input data, as well as to possible shifts in the financial meaning of IRR under changes in the project’s value drivers. We introduce the straight-line rate of return (SLRR), based on the notion of average rate of change, which overcomes all the problems encountered by average ROI and IRR: It always exists, is unique, strongly NPV-consistent for both accept–reject decisions and project ranking, and has an unambiguous financial nature.
Keywords: Finance | Project-based evaluation | Working capital | ROI | IRR | Sensitivity analysis | Net present value | Straight-line | Project ranking
An experimental contingent valuation of users’ attitudes towards a Crowd Management System
یک ارزیابی تجربی از نگرش کاربران نسبت به یک سیستم مدیریت جمعیت-2020
Smart city projects are being launched globally to enhance the well-being of citizens. Meanwhile, the valueadded of the projects is not easy to evaluate due to the non-market nature of the public services provided. This study intends to investigate the attitudes of potential users of a Crowd Management System (CMS) to help with the decision-making on smart city projects. The CMS studied in this paper is applied in large-scale events to enable safe and efficient dissipation of event participants as one of the pilot Smart City projects in Hong Kong. It does so by providing real-time information on public transport for their return journeys when a large number of participants all finish their activities within a short time span. Reducing injuries of pedestrians can be achieved in major gatherings to improve safety. This paper presents an experimental analysis of users’ attitudes towards the CMS with the Contingent Valuation (CV) method. A marathon event in Hong Kong was chosen for an on-thespot survey of actual users as part of an experimental study. Subsequently a similar survey was carried out offsite among marathon runners not participating in that event (as a control group) for data reliability comparison. The Willingness-to-Pay value is also derived from the pooled samples to evaluate users’ attitudes. Besides, the results indicate that runners’ perceived usefulness and online payment habit significantly influence the stated Willingness-to-Pay (WTP) for the CMS in question.
Keywords: Crowd Management System | Contingent Valuation method | Willingness-to-pay | Information and Communication Technology | Smart city