For optical images, cloud and cloud shadow is always a problem during image processing and interpretation. Landsat ETM+ images, as a kind of optical images, are affected by cloud too. On the other hand, microwave images such as ALOS PALSAR images, which depend on microwave, is not affected by cloud, thus they are cloud-free. The aim of this study is to develop a semi-automatic method for removi...

Landsat, first placed in orbit in 1972, established the U.S. as the world leader in land remote sensing. The Landsat system has contributed significantly to the understanding of the Earth’s environment, spawned revolutionary uses of spacebased data by the commercial value-added industry, and encouraged a new generation of commercial satellites that provide regional, high-resolution spatial imag...

The launch of Landsat 7 on April 15, 1999 ushered in a new era of managing global survey missions. For the first time (for Landsat or any similar mission) an automated Long-Term Acquisition Plan (LTAP) was employed to populate the US Archive at the USGS EROS Data Center. The automated LTAP system was designed to globally collect sunlit, essentially cloud-free, and seasonally refreshed Landsat a...

The Operational Land Imager (OLI) on Landsat-8 represents a generational change from heritage Landsat instruments in its design, while it maintains data continuity with the 40+ year Landsat data archive. It preserves the 30-m ground sample distance, 185-km swath width and VIS/NIR/SWIR spectral bands. Furthermore, data continuity resulted from extensive pre-launch and on-orbit calibration and ch...

Fractional vegetation cover (FVC) is an essential land surface parameter for Earth surface process simulations and global change studies. The currently existing FVC products are mostly obtained from low or medium resolution remotely sensed data, while many applications require the fine spatial resolution FVC product. The availability of well-calibrated coverage of Landsat imagery over large are...

In this paper, we perform multi-sensor multi-resolution data fusion of Landsat-5 TM bands (at 30 m spatial resolution) and multispectral bands of World View-2 (WV-2 at 2 m spatial resolution) through linear spectral unmixing model. The advantages of fusing Landsat and WV-2 data are two fold: first, spatial resolution of the Landsat bands increases to WV-2 resolution. Second, integration of data...

The National Aeronautics and Space Administration (NASA) Landsat program has been dedicated to sustaining data continuity over the 20-year period during which Landsat Thematic Mapper (TM) and Enhanced TM Plus (ETM+) sensors have been acquiring images of the earth's surface. In 2000, NASA launched the Earth Observing-1 (EO-1) Advanced Land Imager (ALI) to test new technology that could improve t...

هدف: این پژوهش با هدف ارائه مدل چالش‌های پرورش کودکان کم‌شنوای پیش‌دبستانی از دیدگاه مادران و متخصصان بر اساس نظریه داده‌بنیاد انجام ‌شده است. روش: نمونه 15 مادر کودک کم‌شنوا 4 تا 6 ساله انجمن والدین شهر تهران 5 متخصص حوزه ناشنوا بودند که در سال 1400 استفاده روش نمونه‌گیری هدفمند انتخاب شدند. چالش ­های طریق مصاحبه نیمه ساختاریافته عمیق رسیدن به اشباع نظری جمع‌آوری کدگذاری (کدگذاری باز، محوری ان...

سابقه و هدف: ورود گونه­­ های ماهی مهاجم دراکوسیستم ­های آبی، سبب بروز انواع اثرات منفی اکولوژیکی اقتصادی-اجتماعی می ­­شود. اولین گام در تجزیه تحلیل مخاطرات ناشی از گونه­ غیر­بومی، شناسایی خطر است بر این اساس ابزارهای متعددی برای ارزیابی خطرات تهاجمی غیربومی به منظور پشتیبانی تصمیم گیرندگان گونه ­­ها ایجاد شده است. هدف پژوهش قدرت تیلاپیای شکم قرمز (Coptodon zillii) حوضه آبریز تالاب شادگان (حوضه‌...