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متن کامل


اطلاعات دوره: 
  • سال: 

    1387
  • دوره: 

    19
  • شماره: 

    2-8 (ویژه نامه مهندسی عمران)
  • صفحات: 

    29-38
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    3979
  • دانلود: 

    1043
چکیده: 

مساله برنامه ریزی پرواز شرکتهای هوایی، به طور کلی شامل چهار مساله «زمان بندی پرواز»، «تخصیص ناوگان»، «مسیریابی و تعمیر و نگهداری هواپیما» و «زمان بندی و تخصیص خدمه پروازی» می باشد. در این پژوهش برای نخستین بار مدل ریاضی برنامه ریزی پرواز با ادغام چهار زیر مساله اخیر به طور پیوسته، ساخته و در این مقاله ارایه شده است. اما با توجه به بزرگی مقیاس مدل توسعه یافته، حل آن با بکارگیری روشهای متداول تحقیق در عملیات امکان پذیر نمی باشد، لذا در حل این مساله از روش ابتکاری الگوریتم ژنتیک استفاده شده است. مدل ارایه شده برای داده های واقعی یک شرکت هواپیمایی داخلی به کمک الگوریتم ژنتیک حل شده است. خروجی این مدل علاوه بر زمانهای ورود و خروج پرواز، برای هر مبدا - مقصد، نوع ناوگان تخصیص یافته، هواپیمای تخصیص یافته در هر ناوگان به پرواز مربوطه و خدمه پروازی مربوط به پرواز را تعیین می نماید.

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بازدید 3979

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اطلاعات دوره: 
  • سال: 

    1389
  • دوره: 

    7
  • شماره: 

    19
  • صفحات: 

    70-79
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    1216
  • دانلود: 

    330
چکیده: 

مساله برنامه ریزی تیم پرواز عبارتست از تعیین مجموعه پروازهای متوالی که یک تیم (شامل مهمانداران و کادر فنی) باید انجام دهد. در این مقاله فرض می شود تعداد و مشخصات کلیه پروازهایی که یک شرکت هواپیمایی باید پوشش دهد (شهرهای مبدا و مقصد و زمان پرواز) از پیش معلوم است و باید برنامه کاری هر تیم یا همان لیست و توالی پروازهایی که هر تیم باید انجام دهد را مشخص نمود. طبیعی است که برای پوشش دادن کل پروازهای یک شرکت، می توان مجموعه برنامه های متعددی را تدوین نمود که بابت هر یک هزینه متفاوتی به تیم پرواز پرداخت می شود. هدف این مقاله ارائه یک مدل ریاضی جدید است که قادر خواهد بود حالت پروازهای بدون بلیط را نیز پوشش دهد. مدلهای موجود با هدف کمینه شدن دستمزد پرداختی به تیم پرواز ارایه شده اند اما مدل پیشنهادی بدنبال کمینه کردن هزینه کل (دستمزد خلبانان و پروازهای بدون بلیط) است.

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اطلاعات دوره: 
  • سال: 

    1403
  • دوره: 

    13
  • شماره: 

    4
  • صفحات: 

    41-60
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    32
  • دانلود: 

    7
چکیده: 

in this research, their effects on the Flight of airplanes were investigated. The study area is the country of Iran, and the Flight routes of Kermanshah, Ahvaz and BandarAbbas to Tehran. The research data includes maps of the Vertical Transect (profile) of the jet stream, the daily average of the Zonal wind (U-Wind) and meridional wind (V-Wind) components for the winter period of 2018 through NOAA/NCEP environmental databases. Also, Flight route information was received from FlightRadar24 and Flightaware systems. First, by using Vertical Transect maps, the days containing strong U-Wind were extracted, and the average position of the core of the Jet Streams in the Zonal and meridional wind components, the Tropospheric level of 200 HP was detected. The list of Flights was prepared, and the Zonal Wind maps were produced. Finally, the height of the Flights was compared with the level of the currents of the Jet Streams, and the influence or lack of influence of the Jet Streams on the Flights was studied. According to the results of the research, all the Jet Streams caused turbulence for all Flights, and they caused a decrease in the speed of Flights between Ahvaz and BandarAbbas to Tehran and an increase in the speed of Flights between Kermanshah and Tehran according to the direction and type of Jet Streams. It was also found that all the Jet Streams had a speed of more than 90 knots, so the capacity to create tension and turbulence such as CAT was seen in them

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مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
نویسنده: 

Moghadas Nian Seyyed Abdol Hojjat | Ataei Aghdam Mahisa

اطلاعات دوره: 
  • سال: 

    2024
  • دوره: 

    8
تعامل: 
  • بازدید: 

    74
  • دانلود: 

    0
چکیده: 

This study delves into the pivotal role of Key Performance Indicators (KPIs) in optimizing Flight planning and management within the airline industry. By employing a mixed-methods approach, combining quantitative and qualitative analyses, the research investigates how KPI-driven strategies impact operational efficiency, safety compliance, cost management, and customer satisfaction. The findings reveal that meticulously selected and managed KPIs significantly enhance operational outcomes, guiding strategic decisions and fostering a culture of continuous improvement. Comparative and case study analyses further illustrate the tangible benefits of successful KPI implementation in real-world settings, providing valuable insights for Flight planning managers and airline executives. This research underscores the necessity of adopting a holistic, KPI-driven approach to navigate the complexities of the contemporary aviation environment effectively. It offers strategic recommendations for integrating technology, prioritizing safety, and enhancing customer experiences. The study contributes to the theoretical and practical discourse on airline operations, highlighting the enduring value of KPIs in achieving operational excellence and strategic success in a rapidly evolving industry.

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نویسنده: 

HEIDARI A.A. | ABBASPOUR R.ALI

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    13
تعامل: 
  • بازدید: 

    136
  • دانلود: 

    0
چکیده: 

THIS ARTICLE ADDRESSES A NEW APPROACH TO 3D PATH planning OF UCAVS. TO SOLVE THIS NP-HARD PROBLEM, IMPERIALIST COMPETITIVE ALGORITHM (ICA) WAS EXTENDED FOR PATH planning PROBLEM. THIS RESEARCH IS RELATED TO FINDING OPTIMAL TRAJECTORIES BEFORE UCAV MISSIONS. DEVELOPED PLANNER PROVIDES 3D OPTIMAL PATHS FOR UCAV Flight WITH REAL DTM OF TEHRAN ENVIRONMENT. IN UCAV MISSION, FINAL COMPUTED PATHS SHOULD BE SMOOTH THAT MADE THE PATH planning PROBLEMS CONSTRAINED. THIS PLANNER CAN OFFER FLYABLE 3D PATHS BASED ON MISSION REQUIREMENTS. IT’S A COMPREHENSIVE STUDY FOR EFFICIENCY EVALUATION OF EA PLANNERS, AND THEN NOVEL APPROACH WILL BE PROPOSED AND COMPARED TO ICA, GA, ABC AND PSO ALGORITHMS. THEN PATH planning TASK OF UCAV IS PERFORMED. SIMULATIONS SHOW ADVANTAGE OF PROPOSED METHODOLOGY.

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نویسنده: 

HAKIMI A. | BINAZADEH T. | Shafiei M.H.

اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    14
تعامل: 
  • بازدید: 

    153
  • دانلود: 

    0
چکیده: 

THIS PAPER PROPOSES A METHOD TO GENERATE A UNIFORM Flight PATH FOR SURVEILLANCE OF A REGION, USING THE LIMIT CYCLE CONCEPT. THE PROPOSED METHOD IS BASED ON THE LIMIT CYCLE CHARACTERISTIC OF SECOND ORDER NONLINEAR SYSTEMS FOR REAL-TIME Flight PATH planning FOR UAVS. THE GENERATED Flight PATH COVERS WHOLE AREA OF A CIRCLE WITH ARBITRARY RADIUS AND DENSITY OF THE TRAJECTORIES. UAVS BY TRACKING SUCH TRAJECTORIES ARE ABLE TO GET THE PRECISE AERIAL PHOTOS OR MOVIES (OR ANOTHER TASK WHICH NEEDS SUCH A TRAJECTORY). THE PROPOSED REAL-TIME Flight PATH IS DIVIDED TO THREE MAIN PHASES; IN THE FIRST PHASE, THE UAV TAKES OFF FROM THE LAUNCH STATION AND MOVES TO THE NEAR OF THE CENTER OF THE CONSIDERED CIRCULAR SIGHTLY AREA FOR GETTING THE AERIAL PHOTOS OR MOVIES. THIS PHASE IS ALSO DONE BASED ON THE LIMIT CYCLE NAVIGATION METHOD TO GENERATE THE SAFE TRAJECTORY AGAINST THE OBSTACLES (OBSTACLE AVOIDANCE USING LIMIT CYCLE NAVIGATION). IN THE SECOND PHASE, THE FLYING OBJECT TRACKS A UNIFORM HELICOIDAL TRAJECTORY TO REACH THE CIRCULAR LIMIT CYCLE, TO SCAN A CIRCULAR SIGHTLY AREA, COMPLETELY. IN THE LAST PHASE, WHEN THE SCANNING OF THE SIGHTLY AREA HAS BEEN ACCOMPLISHED, THE UAV COMES BACK TO THE LAUNCH STATION ON THE TRAJECTORY THAT PRODUCED BY A SIMILAR PROCEDURE OF THE FIRST PHASE. FINALLY, SOME SIMULATIONS ARE CARRIED OUT TO SHOW THE Flight PATH GENERATED BY THIS IDEA.

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بازدید 153

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نویسندگان: 

HADADPOUR H.

نشریه: 

ESTEGHLAL

اطلاعات دوره: 
  • سال: 

    2006
  • دوره: 

    25
  • شماره: 

    1
  • صفحات: 

    217-226
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    269
  • دانلود: 

    0
چکیده: 

A method is presented for the stress analysis of Flight vehicles under different Flight conditions including gust and control surface deflection (or maneuver) using the governing equations of rigid-body motions and elastic deformations. The Lagrangian approach is used to derive the governing equations of motions. For this purpose, the basic equations of motions are derived in terms of potential energy, kinetic energy and generalized forces, which are, in turn, computed in terms of rigid-body motion variables, elastic mode shapes and cla(x) distribution for aerodynamic forces. By replacing them into the relations obtained, the governing equations for aeroelastic behavior of the vehicle are derived. The system of aeroelastic equations of motions is solved in time domain using numerical methods. The stress distribution is determined using the relation between modal variables and strain at each point. Finally, the prepared code is verified through comparison of the results obtained from the proposed method for the stability of a rocket and the same results reported by other studies. Also additional information such as maximum stress in the body is presented for various Flight conditions.

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بازدید 269

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اطلاعات دوره: 
  • سال: 

    1399
  • دوره: 

    9
  • شماره: 

    1
  • صفحات: 

    23-38
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    125
  • دانلود: 

    55
چکیده: 

مکانیزم پرواز یک پرنده تا حد زیادی مشابه یک هواپیما است؛ چرا که هر دو از قوانین آیرودینامیکی یکسانی تبعیت می کنند. برای پرندگان مهاجر که دارای عدد رینولدز نسبتا بالاتری در هنگام پرواز هستند، این تشابه بسیار زیاد است. هدف این مقاله، تحلیل عملکرد پروازی پرندگان به کمک معادلات مکانیک پرواز و مقایسه این مدل با نتایج پرواز آنها است تا به کمک آن بتوان روش های مورد استفاده را اعتبارسنجی نمود و در آینده مشخصات عملکردی پهپادهای بالزن را بدست آورد. برای این منظور، به بررسی عملکرد پروازی غاز شمالی (گونه ای از پرندگان مهاجر) پرداخته می شود: ابتدا پرواز پرندگان مهاجر مدلسازی می شود. پس از آن، توان شیمیایی و مکانیکی پرنده بدست آمده و تحلیل می گردد. سپس، ضمن استخراج روابط مناسب عملکرد پرواز، چندین متغیر عملکردی مهم همچون ضریب بازدهی آیرودینامیکی، نرخ اوج گیری، گرادیان اوج گیری، محدوده ی بهینه سرعت پرواز و برد پروازی کسب می شود. در نهایت، اثر تغییر ارتفاع و وزن پرنده و همچنین اثر تغییرات دما بر این متغیرهای عملکردی مورد مطالعه قرار می گیرد.

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اطلاعات دوره: 
  • سال: 

    1384
  • دوره: 

    1
  • شماره: 

    2
  • صفحات: 

    31-46
تعامل: 
  • استنادات: 

    1
  • بازدید: 

    1805
  • دانلود: 

    307
چکیده: 

اغلب شبیه سازی پرواز برای تحلیل رفتار هواپیما مورد استفاده قرار می گیرد و داده های خروجی آن با داده های تست پرواز مقایسه می شود. در این مقاله از روش های پیشرفته آماری و آنالیز طیفی، اعتبار مدل های ریاضی به کار گرفته شده در شبیه سازی ارزیابی شده است. همچنین، برای تایید این متدولوژی مقایسه ای بین نتایج شبیه سازی و تست پروازی سه نمونه پرواز واقعی به عمل آمده است. این مقایسه توافق های نسبتا نزدیکی را نشان می دهد.

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نویسندگان: 

Hanaee Toktam | Farhangdoust Hadi

اطلاعات دوره: 
  • سال: 

    1402
  • دوره: 

    11
  • شماره: 

    2
  • صفحات: 

    133-152
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    202
  • دانلود: 

    30
چکیده: 

ABSTRACT The attention of contemporary planners to environmental factors and increasing awareness and communication of man with his surrounding environment has increased the layers and defining factors of design and planning concepts. In such a way, a common problem with the issue of environmental capabilities to respond was put in front of the planners. The collection of ideas presented in this era was in the form of responsive planning, focusing on the maximum use of environmental capabilities. The necessity of the emergence of a comprehensive discourse to overcome the plurality of factors, definitions and design methods in the environmental fields has been given less attention. Based on this, the current research aims to organize the leading theories in this field in a targeted manner and seeks to improve them based on their synergy. The structural question of this research is the meanings, examples and meaningful contexts of flexibility in various aspects and scales of urban planning. The research method used is qualitative thematic analysis with the help of artificial intelligence in MAXQDA software in a 6-step processing process. The important application of this research is to structure the minds of the planners of this field to reduce the scattered and interdisciplinary problems of the resources. The results of this research revealed dimensions such as identification and recognizability, diversity and changeability, adaptability and expandability, distribution, separation and continuity, organization and compatibility in the field of flexibility and related to the corresponding parts in urban planning   Extended Abstract Introduction Responsiveness-based design and planning emphasizing the maximum use of environmental capacities to meet users' needs implicitly cause a targeted improvement of environmental quality. As the environmental awareness of contemporary man has expanded and the platforms have become more diverse, many challenges are raised in the field of environment-oriented in the field of infrastructure quality and service provision. Urban developments and new developments in cities should be interpreted with integrated conceptualization. The conceptualization of interpretive flexibility in the planning and designing of public spaces in the city is used as an interdisciplinary perspective in urban space design to open and discuss its connection and potential as an approach to strengthening social cohesion and inclusion. The general definition of flexibility is that it can create places with new forms of meaning and be used for different groups to strengthen its coherence and multidisciplinary inclusion in terms of design and planning of space and body. On this basis, the concept of flexibility is proposed as a principle in the context of design and planning due to its wide range of effects on background phenomena. The history of such a role can be seen in the diversity of users' needs. In such a way, it is impossible to express the specific time and area of the need to pay attention to this concept. This is in line with Oldenburg's theory of "social public spaces," in which being in public space, communicating with people and the environment through observing the streets, sidewalks, squares, and parks of the city is a necessary step for people as a part of their social life. The meaningfulness of the design of the artificial environment was considered. In any case, in the contemporary era, on the one hand, at the same time as the quantitative and qualitative increase of human environmental awareness, there is no longer any phenomenon in the eyes of contemporary man arising from a unique aspect and range of factors. On the other hand, his life needs in the individual and collective dimensions have seen a high diversity, which has led to the formation of multiple semantic domains of past flexibility. The meaning of flexibility in such an interdisciplinary platform and basic design refers to the concept of understanding and responding quickly and efficiently to environmental changes. Such a holistic definition for this broad field of environmental design means the implicit acceptance of the role of scale in the meaningful domain of these concepts. On a macro scale, it means making design options to increase the presence, participation, and power of choices of users of the environment in participatory urban planning and design methods, and on a small scale, it means making design options to increase spatial quality and, as a result, the quality of activities. The daily activities of environmental users are through selection against the "dominant space." Flexibility at different scales is crucial for dimensional optimization, shaping, and structuring spatial features, leading to improved performance of space components and spaces. The development of the concept of "flexibility" from various studies in metropolitan to micro scales, such as interior architecture, allows it to pass the discourse of responsiveness to provide a broad approach to environmental design in which different values, interests, and priorities are prioritized. As a result, the issue of flexibility in environmental design has been raised as a multi-dimensional field in the design and planning of the basic environment. The breadth and complexity of this concept have made the researchers of this field deal with it in one or more ways, and it has been avoided to provide a comprehensive framework about the nature and structuring processes. The current research presents a structured view of flexibility in architecture and urban planning with an environmental approach.   Methodology The methodology to achieve this goal is to use the macro research method and achieve a comprehensive framework by combining categorized interpretations. In such a way that by sorting and categorizing these concepts and bases in a new way, he has found a new level of theoretical findings, which will be a suitable answer for the gaps in scientific knowledge and scientific methods created in this field. In this context, the research method "thematic analysis" has been used with a qualitative approach and the use of library resources. Also, to overcome the breadth and complexity of these concepts and the multi-layer networking of concepts in this research method, artificial intelligence has been used in MAXQDA research assistance software.   Results and discussion In the meantime, attention should also be paid to the fields of influence and application of the results of this research because designers refer to flexibility as the creator of environmental qualities, including dynamism. Also, since flexibility, along with the principles of readability and adaptability, affect the lifestyle and behavioral patterns of the audience of environmental design in architecture and urban planning, it will also be effective in dealing with the challenge of complexity in environmental design factors. One of the key questions for achieving research goals on this issue is how flexibility in environmental design impacts the relationship between flexibility and scale.   Conclusion The most important finding of this research suggests that first, it requires a focus on the conditions under which the processes of perceiving human abilities and discovering the needs of the human audience can manifest. The theoretical framework arises from a comparative approach between design disciplines. These conditions are independent of the final state of the design product, and strengthening the environmental capacities will lead to a direction and an area that includes environmental flexibility. By responding to new situations, the construction of the space and the body within a space building can be adapted to various configurations. Even though the environment may remain constant, the designed place will continue functioning as a strong living system over time.  It also seems that the nature of issues related to flexibility has complexity. Considering that the quality of flexibility in urban planning and architecture is significant in multilevel and multifaceted scales from micro to macro, it is important to pay attention to the scale of different variables. In order to reduce this problem, the consistency and adjustment of the scale of the variables measured in a specific analysis should be considered in the first step.   Funding There is no funding support.   Authors’ Contribution All of the authors approved the content of the manuscript and agreed on all aspects of the work.   Conflict of Interest Authors declared no conflict of interest.   Acknowledgments We are grateful to all the scientific.

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email sharing button
email sharing button
sharethis sharing button