In-orbit optical performance assessment of Geostationary Ocean Color Imager
After Geostationary Ocean Color Imager (GOCI) was launched at June 27th, 2010, it is operated to observe the Korean peninsula on the geostationary orbit as one of the three main payloads in COMS satellite. Generally, the performance indicators are Ground Sample Distance (GSD), Modulation Transfer Function (MTF), and Signal to Noise Ratio (SNR) that verify the optical performance of payload. Most of all, the MTF performance is widely used since it is closely related to reliability and accuracy of observational target information in aspects of satellite image application. Especially, in case of ocean color sensor, for confirming the ability of GOCI to separate the slight difference of ocean color information, on-orbit MTF performance test and SNR assessment should be performed.
Uzaktan Algılama Uydu Görüntüleme Sistemleri İçin Sinyal Gürültü Oranı Hesaplama Yöntemi
Sinyal Gurultu Orani (SGO) uydu goruntuleme sistemlerinde goruntu kalitesi ile radyometrik performansi birbirine baglayan bir olcut olarak kullanilir ve uzaktan algilama uydu goruntuleme sistemlerinde goruntu kalitesini gosteren parametrelerden birisidir. Uzaktan algilama uydu goruntu sistemi tasarim asamasinda SGO hesaplamalarinin ve analizlerinin yapilmasi gerekmektedir. Bu hesaplama ve analiz calismalari tasarima yon verilmesi ve tasarimin dogrulanmasi icin onem tasimaktadir. Tasarlanan optik goruntuleme sistemine kaliteli bir goruntu olusturabilecek isik akisinin ulastigi ve ulasan bu isik akisinin sensor uzerinde yeteri kadar elektron olusturdugu gosterilmelidir. Bu calismada alcak irtifa yorungesinde gorev alan yakin kizil otesi bantta calisan bir uydu goruntuleme sisteminin spektral ve toplam isik aki miktari hesaplamasi yapilarak SGO analizi sunulmustur. Optik sistemin goruntu kalitesinin tasarim asamasinda tahmin edilebilmesi ve optik giris aciklik capinin belirlenmesi icin sensore gelen isik miktarinin hesaplanmasi ve SGO analizinin yapilmasi gerekmektedir. Bu calismada uzaktan algilama uydu goruntuleme sistemleri icin yer yuzunden yansiyip atmosferi gecerek goruntuleme sensorunun bir pikseline olusan toplam elektron sinyal miktari hesaplama yontemi verilmis ve SGO analizi yapilmistir. Onerilen SGO analiziyle optik goruntuleme sisteminin 2,5 milisaniye goruntu alma suresince dusuk kapasitans modda calistirilmasiyla sensorun bir pikselinin %28,2'i elektronlarla doldugu, kazancin 0,56 V ve SGO'nin 861 oldugu tespit edilmistir.
Use of laser scanning confocal microscopy for morphological taxonomy and the potential for digital type specimens (e-types)
The use of laser scanning confocal microscopy (LSCM) for creating taxonomic descriptions of copepods is investigated. A new technique is described, which employs a contour filter to process digital LSCM images, allowing taxonomic information to be quickly and accu- rately distilled into a simple illustration. LSCM allows the imaging of whole specimens, which can be rotated and viewed from any angle—a major benefit over light microscopy. Using this tech- nique, it is suggested that taxonomic descriptions can be rapidly produced in a fraction of the time required to produce similar descriptions using traditional light microscopy and hand drawing techniques. Good staining of specimens is, however, essential to produce accurate descriptions and more research is required in this area. The use of LSCM for morphological taxonomy shows great potential, not only for producing taxonomic descriptions, but also providing a comple - mentary adjunct to traditional type specimens in the form of 3D digital 'e-types' deposited in recognised international databases.