An Application of SMART Method in vendor selection of Satellite Systems Case study of Indonesia Remote Sensing Satellite Systems (InaRSSat)

The heritage of Lembah Bujang, Kedah is important as a starting point to understand the origins and history of civilization in Malaysia. This research is to analyze the spectral reflectance of shrines properties in an identified area by using remote sensing techniques in conserving this cultural heritage site. The remote sensing device (Spectroradiometer) was used to measure the spectral reflectance of the source of shrines in the study area. This tool was applied for reflectance’s test over properties such as ancient brick, granite, literates and iron in a different two study areas consist of Lembah Bujang and Kompleks Sungai Batu. Remote sensing test properties demonstrate that discrimination of properties types of each civilization is possible through reflection measurement, but that discrimination is complicated by surface conditions, such as weathering and lichen growth. Comparison between clays, granite and iron show that clays to be more reflective than granite and iron. This result will help more in our further study on detecting these properties direct through remote sensing imagery and will be helpful in developing new indexes and selection of threshold value on shrines material in the case study of Lembah Bujang.

Download Full-text

The Optimal Location of Ground-Based GNSS Augmentation Transceivers

Geosciences ◽

10.3390/geosciences9030107 ◽

2019 ◽

Vol 9 (3) ◽

pp. 107 ◽

Cited By ~ 2

Author(s):

Jacek Rapinski ◽

Artur Janowski

Keyword(s):

Wide Band ◽

Optimal Location ◽

Point Of View ◽

Global Navigation Satellite Systems ◽

Design Stage ◽

Shift Measurement ◽

Satellite Systems ◽

Global Navigation Satellite ◽

Selection Of

Modern Global Navigation Satellite Systems (GNSS) allow for positioning with accuracies ranging from tens of meters to single millimeters depending on user requirements and available equipment. A major disadvantage of these systems is their unavailability or limited availability when the sky is obstructed. One solution is to use additional range measurements from ground-based nodes located in the vicinity of the receiver. The highest accuracy of distance measurement can be achieved using ultra wide band (UWB) or ZigBee phase shift measurement. The position of the additional transmitter must be carefully selected in order to obtain the optimal improvement in the dilution of precision (DOP), which reflects the improvement in the geometry of solution. The presented case study depicts a method for selecting the optimal location of a ground-based ranging source. It is based on a search of a minimum DOP value as a transmitter location function. The parameters of objective function are the elevation and azimuth of the transceiver. The solution was based on a limited-memory Broyden–Fletcher–Goldfarb–Shanno with Box constraints (L-BFGS-B) method and a numerical optimization algorithm for parameter value estimation. The presented approach allows for the selection of the optimal location of a ground-based source of ranging signals in GNSS processing from a geometry of solution point of view. This can be useful at the design stage of an augmentation network of ground-based transceivers. This article presents a theoretical basis and a case study presenting the selection of the optimal location of a ground-based ranging source.

Download Full-text