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"Novelized account of an engineer involved in to bring national satellite communication to Indonesia."

"Perencanaan tata ruang sebagai dasar pembangunan suatu wilayah, memerlukan informasi spasial yang akurat dan lengkap agar hasil perencanaan tata ruang yang dihasilkan tepat sasaran. Peta dasar rupa bumi sebagai informasi spasial utama di Indonesia pada umumnya menggunakan sumber data foto udara. Perkembangan teknologi penginderaan jauh akhir-akhir ini telah dapat mengasilkan citra satelit dengan resolusi spasial yang tinggi. Salah satunya adalah Citra ALOS PRISM dengan resolusi 2.5 m. Pemetaan rupa bumi skala 1:25.000 menggunakan Citra ALOS PRISM tersebut menghasilkan peta rupabumi dengan tingkat akurasi Horizontal (x,y) yang baik secara relatif terhadap peta RBI (Rupa Bumi Indonesia) skala 1:25.000 dan secara absolut terhadap hasil pengukuran di lapangan. Sementara tingkat akurasi vertikal-nya dapat memenuhi standar pemetaan nasional hanya pada wilayah topografi datar tetapi tidak dapat memenuhi standar pada wilayah topografi bergelombang dan bergunung.

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Spatial planning as the foundation of spatial development needs the accurate and complete spatial information so the results could meet the aim. Topographic map is one of the main spatial information that generally uses the source of the aerial photograph data. Recent development of remote sensing technology produce the satellite image with the high spatial resolution. One of them is ALOS PRISM with the spatial resolution 2.5 m. Topographic mapping at various topographic area using ALOS PRISM image has produced map at scale 1:25.000 with the level of the Horizontal accuracy (x,y) that was relatively good against the RBI map at the scale 1:25.000 and absolutely towards ground-surveyed reference points. While the level of it’s vertical accuracy could meet the standard of the national mapping only on the flat area but could not meet the standard on undulating and mountainous area."

"Kebutuhan analisa global terhadap variabilitas fresh water budget, evaporasi-presipitasi (E-P) dan salinitas sangat penting untuk memahami sistem iklim bumi secara lebih baik. Namun, sering terkendala oleh ketersediaan data evaporasi, presipitasi dan sea surface salinity (SSS) secara time series. Aquarius merupakan wahana satelit khusus untuk melakukan pengukuran salinitas permukaan laut, SSS. Variabilitas evaporasi-presipitasi (E-P) dan SSS secara spasial dan temporal di lautan Benua Maritim Indonesia (BMI), yaitu di Selat Karimata, Laut Jawa dan Laut Banda dapat diidentifikasi dari data re-analysis ERA INTERIM ECMWF dan satelit Aquarius secara bulanan selama periode 2011-2005 dapat menggambarkan variabilitas. Hasil estimasi menunjukkan nilai evaporasi di ketiga perairan sekitar sekitar -0,025 hingga -0,059 Sv. Hubungan antara SSS dan E-P terlihat nyata di perairan Indonesia. Variasi E-P dalam menjelaskan SSS hampir mencapai sekitar setengahnya (27-50%), sedangkan sisanya dijelaskan oleh faktor lainnya. Variasi SSS dapat dijelaskan oleh E-P dengan pengaruh dominan dari presipitasi. Hal ini terlihat dari tingginya SSS ketika presipitasi menurun di ketiga perairan. Hubungan antara perubahan naiknya gradien E-P dan SSS terhadap naiknya kecepatan angin zonal dan meridional juga terlihat pada ketiga perairan. Untuk mengetahui variabel lain yang mempengaruhi SSS dilakukan analisis regresi linier antara kecepatan angin dengan SSS. Kecepatan angin memberikan pengaruh signifikan pada SSS di lautan BMI. Di Selat Karimata, hasil koefisien determinasi (R2) antara kecepatan angin zonal dan meridional mendominasi sekitar hampir setengahnya (38-49%), sedangkan sisanya dijelaskan oleh faktor lainnya. Artinya angin dapat mempengaruhi SSS melalui proses evaporasi, peningkatan kecepatan angin akan menyebabkan meningkatnya evaporasi. Peningkatan evaporasi akan mempengaruhi kadar salinitas di perairan.

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Needs of analysis of oceanic fresh water flux evaporation-precipitation, (EP) and salinity variability is very important to better understand the Earth's climate system and global water cycle. The availability of evaporation-precipitation (E-P) and sea surface salinity (SSS) time series data still sparsely observed. Aquarius is the fist special satellites used to measure sea surface salinity (SSS). Variability of evaporation-precipitation (E-P) and SSS can be described spatially and temporally over Indonesian Maritime Continent (IMC) oceans using ECMWF ERA INTERIM re-analysis and Aquarius retrieval data during the period 2011-2005.

Estimation of oceanic evaporation over Karimata Strait, Java Sea and Banda Sea showed approximately of -0.025 to -0.059 Sv. Liner relationship between oceanic fresh water flux (E-P) and SSS significantly different over the Indonesian ocean and expressed in determination coefficient (R2). Variance of E-P explained SSS monthly period over the three ocean waters almost reached 27-53%, the rest of it caused by other variables. From the two primary components of the fresh water flux, precipitation (P) dominates the influence on SSS. The result showed that SSS increased when the precipitation was decreased. On the other hand, the wind speed also influences SSS over Indonesian oceans. This relationship also showed that the increasing of E-P and SSS gradient will be followed by the higher wind speed. Regression analysis also applied to identify the relationship between wind speed and SSS. In Karimata Strait, the wind speed of zonal and meridional dominates approximately 38-49% of SSS, while the rest was explained by other factors. Wind speed dominates the primary component of the fresh water flux through evaporation processing. The wind speed increased the evaporation, consequently the sea surface salinity variation will be changed."

"The book provides an introduction to differential geometry of curves and surfaces. The theory of curves starts with a discussion of possible definitions of the concept of curve, proving in particular the classification of 1-dimensional manifolds. We then present the classical local theory of parametrized plane and space curves (curves in n-dimensional space are discussed in the complementary material): curvature, torsion, Frenet’s formulas and the fundamental theorem of the local theory of curves. Then, after a self-contained presentation of degree theory for continuous self-maps of the circumference, we study the global theory of plane curves, introducing winding and rotation numbers, and proving the Jordan curve theorem for curves of class C2, and Hopf theorem on the rotation number of closed simple curves. The local theory of surfaces begins with a comparison of the concept of parametrized (i.e., immersed) surface with the concept of regular (i.e., embedded) surface. We then develop the basic differential geometry of surfaces in R3: definitions, examples, differentiable maps and functions, tangent vectors (presented both as vectors tangent to curves in the surface and as derivations on germs of differentiable functions; we shall consistently use both approaches in the whole book) and orientation. Next we study the several notions of curvature on a surface, stressing both the geometrical meaning of the objects introduced and the algebraic/analytical methods needed to study them via the Gauss map, up to the proof of Gauss’ Teorema Egregium. Then we introduce vector fields on a surface (flow, first integrals, integral curves) and geodesics (definition, basic properties, geodesic curvature, and, in the complementary material, a full proof of minimizing properties of geodesics and of the Hopf-Rinow theorem for surfaces). Then we shall present a proof of the celebrated Gauss-Bonnet theorem, both in its local and in its global form, using basic properties (fully proved in the complementary material) of triangulations of surfaces. As an application, we shall prove the Poincaré-Hopf theorem on zeroes of vector fields. Finally, the last chapter will be devoted to several important results on the global theory of surfaces, like for instance the characterization of surfaces with constant Gaussian curvature, and the orientability of compact surfaces in R3."