تاثیر عدم اطمینان بر معیارهای مخاطره در مدیریت مخزن

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار/ گروه مهندسی آب، دانشکده کشاورزی دانشگاه شیراز، ایران

2 دانشجوی کارشناسی ارشد/گروه مهندسی آب، دانشکده کشاورزی دانشگاه شیراز، ایران.

چکیده

در شرایطی که یک سیستم پیچیده مورد مطالعه قرار می‌گیرد یا در مورد آن اطلاعات زیادی در دسترس نیست، طراحی، پیش‌بینی و ارزیابی راندمانها، نتیجه نهایی اجرای پروژه و سود و زیانهای حاصله از آن چندان دقیق نخواهند بود. در چنین شرایطی ارزیابی تاثیر عدم اطمینان، حتی بر شاخصهای خطرپذیری که خود زیر مجموعه‌ای از عدم اطمینان به حساب می‌آیند، ضروری است. هدف اصلی از این مقاله معرفی و بررسی تاثیر دو عامل بروز عدم اطمینان (عدم اطمینان آماری و عدم اطمینان پارامتری) بر معیارهای مخاطره مورد استفاده در شبیه‌سازی و بهینه‌سازی مخزن می‌باشد. در قسمت شبیه‌سازی، تاثیر عدم اطمینان آماری و پارامتری بر معیارهای متداول مخاطره (معیار اعتمادپذیری حجمی و معیار اعتمادپذیری شمارشی) و همچنین دو معیار دیگر مخاطره (آسیب‌پذیری و برگشت‌پذیری) بررسی می‌گردد. در قسمت بهینه‌سازی تاثیر وارد کردن عدم اطمینان بر کارایی قانون کاربری مخزن بررسی می‌شود. در این خصوص تاثیر عدم اطمینان آماری بر دو معیار مخاطره (قابلیت اعتماد پذیری شمارشی و هدرروی) مورد ارزیابی قرار می‌گیرد. برای این منظور دو مخزن در حال ساخت استان فارس برای مطالعه انتخاب می‌شوند. نتایج حاصل از این مطالعه نشان خواهد داد که وارد کردن عدم اطمینان (آماری یا پارامتری) بسته به واریانس جریانهای ورودی به مخزن سد و مدیریت مخزن و آب رها شده از آن، تاثیرات و نتایج متفاوتی را بر شاخصهای مخاطره ایجاد می‌کند. نتایج چنین تحقیقاتی می‌تواند طراحان را در انتخاب شاخصهای مناسب مخاطره برای مدیریت مخزن یاری دهد.

کلیدواژه‌ها


عنوان مقاله [English]

Impact of Uncertainty on Risk indices in Reservoir Operation

نویسندگان [English]

  • A Ganji 1
  • D Khalili 1
  • M Homayoun-far 2
1 Assistant Professor, Department of Water Engineering, Shiraz University, Shiraz, Iran
2 Graduate student, Department of Water Engineering, Shiraz University, Shiraz, Iran
چکیده [English]

As a result of system complexity and incomplete information, the planning process, the  “with” and “without” conditions, the project's performance and impacts, and the benefits and costs are never certain. Accordingly, the valuation of uncertainty is a “must”, even on the risk indices as a sub set of uncertainty. This paper focuses on the effects of two main sources of uncertainty; i.e. data and parameter uncertainty, on the risk indices in reservoir simulation and optimization. In reservoir simulation, the effects of uncertainties in simple/disaggregated time series models are studied on the well-known reservoir efficiency indices; i.e. volumetric and occurrence reliabilities. Two additional risk indices; i.e. vulnerability and resilience are also studied. A stochastic dynamic programming model (DPR) is used to study the effects of data continuity uncertainty on reservoir operation rule. In this case the effects of data continuity uncertainty on two indices of Reliability and Losses have been evaluated. Two reservoirs under construction in Fars province, IRAN, have been selected for case study. The results show that the incorporation of uncertainty (i.e. data/parameter uncertainty) in simulation and optimization impact the risk indices differently as the flow variability condition and reservoir storage and  operation changes. These results can help the designer to select the appropriate risk indices for reservoir operation.

کلیدواژه‌ها [English]

  • risk
  • Uncertainty
  • Reservoir management
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