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.
Impact of a visual decision support tool in project control: A comparative study using eye tracking
تأثیر یک ابزار پشتیبانی از تصمیم بصری در کنترل پروژه: یک مطالعه مقایسه ای با استفاده از ردیابی چشم-2020
This paper presents the results of a comparative study where two decision support tools in project control have been selected: the S-Curve and Activity Gazer. The objective of the research is to characterize the impact of the visual decision-support tool in project control on the project planners decision. Using eye tracking, a withinsubject experiment was conducted with 17 participants where they were asked to make a diagnostic on a project portfolio. Results show that, despite the fact that a representation using the S-Curve helps reduce the time of diagnostics, both tools seem to have the same effect on the quality of the diagnostic by the participant. Also, we find that a representation where Activity Gazer is present is less mentally demanding than a representation where the S-Curve is present. These results suggest that the S-Curve could be improved to reduce the mental charge needed to analyze it and that new visualization tools could help project planners in their daily work.
Keywords: Project control | Visualization | Eye tracking | Activity Gazer | Project management | Decision support
MapReduce based tipping point scheduler for parallel image processing
مانبندی نقطه اوج بر اساس MapReduce برای پردازش تصویر موازی-2020
Nowadays, Big Data image processing is very much in need due to its proven success in the field of business information system, medical science and social media. However, as the days are passing by, the computation of Big Data images is becoming more complex which ultimately results in complex resource management and higher task execution time. Researchers have been using a combination of CPU and GPU based computing to cut down the execution time, however, when it comes to scaling of compute nodes, then the combination of CPU and GPU based computing still remains a challenge due to the high commu- nication cost factor. In order to tackle this issue, the Map-Reduce framework has come out to be a viable option as its workflow optimization could be enhanced by changing its underlying job scheduling mech- anism. This paper presents a comparative study of job scheduling algorithms which could be deployed over various Big Data based image processing application and also proposes a tipping point scheduling algorithm to optimize the workflow for job execution on multiple nodes. The evaluation of the proposed scheduling algorithm is done by implementing parallel image segmentation algorithm to detect lung tu- mor for up to 3GB size of image dataset. In terms of performance comprising of task execution time and throughput, the proposed tipping point scheduler has come out to be the best scheduler followed by the Map-Reduce based Fair scheduler. The proposed tipping point scheduler is 1.14 times better than Map- Reduce based Fair scheduler and 1.33 times better than Map-Reduced based FIFO scheduler in terms of task execution time and throughput. In terms of speedup comparison between single node and multiple nodes, the proposed tipping point scheduler attained a speedup of 4.5 X for multi-node architecture.
Keywords: Job scheduler | Workflow optimization | Map-Reduce | Tipping point scheduler | Parallel image segmentation | Lung tumor
How does urban expansion impact people’s exposure to green environments? A comparative study of 290 Chinese cities
توسعه شهری چه تأثیری در مواجهه افراد با محیط های سبز دارد؟ مطالعه تطبیقی 290 شهر چین-2020
Understanding the difference of greenspace in different urban areas is a critical requirement for maintaining urban natural environment and lessening environmental inequality. However, how urban expansion impacts on people’s exposure to ambient green environments has been limitedly addressed. Here we integrated multi-source geospatial big data including mobile-phone location-based service (LBS) data, Sentinel-2, and nighttime light satellite imageries to quantitatively estimate changes in people’s exposure to green environments for 290 cities in China from 1992 to 2015. Results showed that the urban expansion process directly led to differences in green environments between old and new urban areas. These differences were not only observed by the green coverage rate but also captured using a dynamic assessment of people’s exposure to greenspace. For most of China’s large cities, people could enjoy more greenspace in new urban areas than the old ones. A significant day-to-night variation of people’s exposure to greenspace was identified between old and new urban areas. Our results also revealed that urbanization did bring some positive effects to improve green environments for cities located in harsh natural conditions (e.g., semiarid/arid and desert regions).
Keywords: Urban greenspace | Urban sprawl | Exposure assessment | Old and new urban area | Human mobility
Comparative study on the annual performance between loop thermosyphon solar water heating system and conventional solar water heating system
بررسی مقایسه ای عملکرد سالانه بین سیستم گرمایش آب خورشیدی حلقه ترموسیفون و سیستم گرمایش آب خورشیدی معمولی-2020
Loop thermosyphon (LT) is usually introduced to overcome the freezing and corrosion problems associated with the conventional solar water heating (SWH) system. Compared with the conventional SWH system, the LT-SWH system possesses a lower nighttime heat loss because of the thermal diode property of loop thermpsyphon but bigger daytime heat loss because of the secondary heat exchange. However, the effect of above interaction to the system performance is rarely reported based on long-term running. In this study, based on the typical meteorological year data of Fuzhou city, annual performances of above two systems, including the effective number of supplying days, effective heat gain and nighttime heat loss, are comparatively analyzed under two different operational modes. Variations of above mentioned variables with the increment in the set temperature are discussed. The results indicate that, under the discontinuous heating mode, the effective numbers of supplying days of SWH system and LT-SWH system are 139 and 153, respectively. While the numbers of days are respectively 168 and 173 under the continuous heating mode. The SWH system possesses an expected bigger nighttime heat loss ratio with an average annual value of 15.07% corresponding to 6.15% for the LT-SWH system. Particularly, for the LT-SWH system, the different relative magnitudes of heat loss coefficients functioning at different times leads to a smaller temperature drop at night and also a smaller temperature rise at the subsequent day. It generates an unanticipated results that corresponds to the same month from November to April, the two systems have the approximate effective heat gain. The set temperature significantly influences the relative magnitudes of annual effective number of supplying days and annual effective heat gain, the superiority of LT-SWH system gradually diminishes and even reverses with the increment in the set temperature. The bigger daytime heat loss dominating the dominance is responsible for that transition. Combining with a longer static payback period, it is conditional to substitute the conventional SWH system with the LT-SWH system, especially when the water temperature on demand is high.
Keywords: Solar water heating system | Loop thermosyphon solar water heating system | Typical meteorological year | Effective heat gain | Nighttime heat loss
Optimized energy management strategy for grid connected double storage (pumped storage-battery) system powered by renewable energy resources
استراتژی مدیریت انرژی بهینه سازی شده برای سیستم ذخیره دوگانه متصل به شبکه (پمپ باتری ذخیره شده) که از منابع انرژی تجدید پذیر استفاده می شود-2020
This paper presents a grid-connected double storage system (DSS) consisting of pumped-storage hydropower (PSH) and battery. The system is supplied by photovoltaics and wind turbines. In the proposed hybrid system, batteries absorb excess renewable energy that cannot be stored in PSH and they cover loads that cannot be supplied from the water turbine. To improve the system performance, a novel energy management strategy for the DSS is proposed. The strategy is based on an optimized factor that governs the charging process of the DSS. The problem of the optimal system design is solved by a nondominated sorting genetic algorithm (NSGA-II). The multi-objective function considers simultaneously the minimal investment cost and minimal CO2 emissions. A comparative study of photovoltaic/wind/ pumped-storage hydropower and photovoltaic/wind/double storage system is performed to show the effectiveness of the proposed strategy in terms of system economic and environmental performance. The considered location of the PSH station is on Attaqa Mountain at Suez (Egypt). The results indicate the effectiveness of the proposed energy management strategy for the storage system from economic and environmental perspectives. Coupling the battery with the PSH reduces the electricity cost by 22.2% and results in minimal energy exchange with the national grid (5% of the annual demand). A sensitivity analysis shows the largest variation of the electricity cost with changing the capital cost of the solar and wind generators. Also, it is observed that when the load increases, the optimal size of the system components increases, but it isn’t proportional with the demand increase as could be expected.
Keywords: Pumped-storage hydropower | Battery | Double storage system | Renewable energy sources | NSGA-II | Hybrid energy system
Energy management strategy for plug-in hybrid electric vehicle integrated with vehicle-environment cooperation control
استراتژی مدیریت انرژی برای پلاگین در خودروهای برقی هیبریدی یکپارچه با کنترل همکاری خودرو-محیط-2020
Energy management strategies have been proven to be instrumental in fully realizing the potential of plug-in hybrid electric vehicles (PHEVs). This paper proposes an improved adaptive equivalent consumption minimization strategy (IA-ECMS). In an IA-ECMS, the equivalence factor (EF) can be tuned in real time due to integration with the results of the vehicle-environment cooperative control. This study’s main contributions are twofold. First, a novel A-ECMS is developed, in which the EF tuning method is carefully designed based on the results of a correlation study. The study results reveal that EF is determined by the future driving behaviour and the current component status. To ascertain the future driving behaviour, a method based on participatory sensing data (PSD) is used to implement the vehicleenvironment cooperative control. Second, a comparative study of the IA-ECMS and the energy management strategy based on the existing model of predictive control (MPC) is performed. The comparison results show that the application process of the IA-ECMS is similar to that of the MPC-based method except for two main differences. The simulation results demonstrate that the presented IA-ECMS approach could outperform in fuel economy the conventional A-ECMS (CA-ECMS) method.
Keywords: Plug-in hybrid electric vehicles | Adaptive equivalent consumption | minimization strategy | Equivalence factor | Model predictive control | Vehicle-environment cooperative control
Comparative study of energy management strategies for hybrid proton exchange membrane fuel cell four wheel drive electric vehicle
مطالعه تطبیقی استراتژی های مدیریت انرژی برای سلول های سوختی چهار چرخ محرک تبادل پروتون ترکیبی-2020
Nowadays, many researchers have found that the output performance of a hybrid power system is an important reason to determine fuel cell life. Therefore, the energy management strategy for a hybrid power system is the solution to guarantee the normal operation of the system. In this paper, a comparative study of the most commonly used energy management techniques in fuel-cell vehicle applications in a proposed hybrid four-wheeldrive electric vehicle, these schemes include the following: the classical PI, Fuzzy-logic, State machine and frequency decoupling schemes, to ameliorate the dynamic behaviour of the electric vehicle during transients such as the dynamic response and the electric vehicle stability, and to select the best between those techniques based on many criteria which are the hydrogen consumption, the overall efficiency, the state of charge and the stability of DC bus voltage. The general topology of the electric vehicle is composed with three distributed energy resources, the proton exchange membrane Fuel Cell as the main source and a hybrid energy storage system includes batteries and supercapacitor devices as the auxiliary source, this hybrid power sources system driven the four-wheel-drive electric vehicle composed by four induction motors controlled by a direct torque control with space vector modulation.
Keywords: PEM fuel Cell | Electric vehicle | Power management | 4WDEV | DTC-SVM | DC-DC converter
مطالعهی تطبیقی بر روی یک مدل ویک توربین بادی سهبعدی تازه توسعهیافته
سال انتشار: 2019 - تعداد صفحات فایل pdf انگلیسی: 6 - تعداد صفحات فایل doc فارسی: 10
در این پژوهش، یک مدل ویک سهبعدی تحلیلی جهت بررسی اثر ویک توربین بادی توسعه پیدا کرده است و مدل با مدل ویک یکبعدی موجود مقایسه شده است. با توسعهی سریع انرژی بادی فراساحلی و انرژی بادی واقع در ساحل، اندازهی توربینهای بادی بهسرعت افزایش پیدا میکند و فرض سادهی مدل ویک یکبعدی برای توربینهای بادی بزرگ مناسب نمیباشد. مدل ویک یکبعدی که بهصورت متداول مورد استفاده قرار میگیرد، نمیتواند بهصورت دقیق توزیع فضایی را توصیف کند، چون در این مدل فرض میگردد که کمبود باد در مسیر وزش باد بهصورت خطی توزیع میشود. در صورتیکه مدل ویک سهبعدی یک روش مؤثر برای حل این مشکل محسوب میشود. این مدل ویک، کمبود ویک را بهعنوان شکل گوسی فرض میکند و تغییر سرعت باد را در راستای جهت ارتفاع نیز در نظر میگیرد. در این پژوهش، صحت اندازهگیری تونل بادی مدل ویک سهبعدی تعیین شده است که جهت محاسبهی کمبود باد در موقعیت مسیر وزش باد مورد استفاده قرار میگیرد. سپس نتایج با نتایج مدل ویک یکبعدی مقایسه شده است. خطا تحلیل شده است و سپس براساس مقایسهها بحث انجام گرفته است. با توجه به نتایج این پژوهش، مدل ویک سهبعدی جدیدی جهت مطالعهی توزیع ویک برای محققین بهوجود آمده است و یک مدل ویک مناسب میتواند به طرحهای توسعهی مزرعهی بادی بهینهشده کمک کند.
کلمات کلیدی: مدلهای ویک | مدل ویک سهبعدی | تحلیل عددی.
|مقاله ترجمه شده|
Mobile banking use: A comparative study with Brazilian and U:S: participants
استفاده از بانکداری همراه: یک مطالعه مقایسه ای با شرکت کنندگان برزیل و ایالات متحده-2019
As we can see in recent studies on mobile banking, there is an increasing number of papers addressing this new technology. Mobile banking contributes to the quality of life of people living in both developed countries, and also in emerging economies. In this context, we develop this paper in order to compare the determinants of mobile banking use between respondents from two countries with different levels of development: Brazil and the United States. Our theoretical model includes six variables as determinant factors of mobile banking use. In order to analyze path coefficients and test the six hypotheses, we employed a structural equation model. We also employed a quantitative test (multi-group analysis) to analyze the difference of path coefficients between the models of the two countries. The main results indicate similarities among the perceptions of the respondents that participated in the survey, but differences in coefficient magnitude
Keywords: Mobile banking | Emerging economy | Trust | Social influence | Structural equation model
A survey on internet of vehicles: Applications, security issues & solutions
بررسی اینترنت وسایل نقلیه: برنامه ها ، مسائل امنیتی و راه حل ها-2019
Internet of Vehicles (IoV) is an emerging concept in intelligent transportation systems (ITS) to enhance the existing capabilities of VANETs by integrating with the Internet of Things (IoT). IoV has dominated the transportation systems due to numerous special traits like dynamic topological structures, huge network scale, reliable internet connection, compatibility with personal devices and high processing capability, etc. In this review, an in-depth survey of IoV is carried out by discussing the applications of IoV in different areas, as well as the comparative study of IoV and VANETs, is being done. Intelligent transportation system involves a huge amount of dynamic real-time critical data so its security is a major concern. Different security aspects of IoV are studied in this review which includes security requirements, security challenges, and security attacks. After this, existing security solutions of all attacks are elaborated and discussion section is provided to highlight the drawbacks of security solutions deployed for each attack as well as it emphasizes on the attacks for which no security solutions are available. Based on the extensive study conducted on this, it has been found that existing security solutions use conventional cryptographic techniques that affect the performance of the delay sensitive network i.e. IoV and VANETs. So, a lightweight authentication protocol for RFID (Radio-Frequency Identification devices) has also been proposed to overcome the drawbacks of existing solutions and to provide better performance in terms of low detection time, low CPU and memory consumption to strengthen the existing IoV environment.
Keywords: Attacks | Applications | Cryptography | Internet of Vehicles (IoV) | Security | VANETs