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The RISA (Research of Ionospheric Scintillation in Asia) project advanced Ionospheric studies in South-East Asia using space-geodetic systems, in particular by analyzing data acquired using dedicated or available GNSS (Global Navigation Satellite Systems) networks. This project also used activities carried out in the framework of the SCINDA (Scintillation Network Decision Aid) project, which is being implemented by Air Force Research Laboratory in South- East Asia. RISA has investigated the effects of ionospheric scintillation in distributed GNSS networks in Thailand and vicinity and the potential correlation with extreme space weather events. New stations in Asian Institute of Technology, Bangkok; Chiang Mai University, and Phuket have been installed and connected to main SCINDA network. RISA collaborated with International Civil Aviation Organization (ICAO), Boston College, University of California Los Angeles and AMBER projects. This has given an opportunity to develop an intensive research base on impact of solar radiations on Ionosphere as well as Geomagnetism.

Indirect reuse of wastewaters in drinking water supplies is common practice in industrialized states today. The investigations reported upon have been directed towards improvements upon existing techniques more applicable to the tropical and savanna developing country. High costs and technical difficulties have been encountered in the removal of nitrogen and low level organics. In this study, investigations have been conducted into nitrogen stripping by photosynthetic algal growth, using the nitrogen as a nutrient with subsequent algae harvest from ponds, and low level organics reduction by (a) powdered activated carbon treatment and (b) semi-rapid filtration. Several processes including high rate treatment oxidation ponds, dissolved air flotation, roughing filtration, photosynthetic nitrogen stripping ponds, powdered activated carbon adsorption, dual-media filtration and chlorination were developed and specifically applied to domestic wastewater reclamation for drinking water. These were incorporated into two process streams, one using activated carbon for low level organics removal and the other semi-rapid filtration.

The effect of deformation rate on cone index value, plate sinkage parameters, cohesion and internal friction angle was measured in a dry, sandy loam soil and in a saturated, puddled clay soil. The effect on normal pressure on calculated values of cohesion and internal friction angle in the sandy loam soil was also investigated. Deformation rate did not greatly affect any of the soil properties in the sandy loam soil but significantly affected almost all of them in the puddled clay soil. In the sandy loam soil it is shown that normal pressure in the ring shear test must be close to that exerted by the vehicle on the soil otherwise large errors can occur in calculating cohesion and internal friction angle., This article is from 'Proceedings of the International Conference on the Performance of Off-Road Vehicles and Machines (8th). Volume 3. Held at Cambridge England, on August 5-11, 1984,' AD-A150 653, p1135-1148.

Water quality standards were reviewed and tentative stream standards proposed for use in developing countries of Southeast Asia on the basis of legitimate water uses and adaptation of available data to local conditions. A survey of stream standards and water uses applied in the Southeast Asian region indicated that few countries had adopted standards and practically no attempt had been made to adjust to suit local conditions. Experimental studies suggested that oxidation pond effluent would have a beneficial effect on the oxygen balance of a stream under tropical conditions provided that the algal concentration was not more than 10,000 cells/ml after dilution in the stream. Oxidation ponds were assessed as being more attractive than either trickling filter or activated sludge treatment plants for populations less than 175,000 and land rental costs of U.S. $0.10 per square meter per year or less. (Author)

A water treatment filter capable of supplying drinking water to small units in the field has been developed and successfully tested over a limited range of field conditions in Thailand. The filter unit contained shredded coconut fiber and burnt rice husks as filter media, two readily available and inexpensive materials found throughout most of Southeast Asia. The clarity of the treated water was generally less than five units of turbidity (JTU) and color free. Disinfection with one mg/l chlorine or less is necessary to insure USPHS Drinking Water Standards. A water treatment canister, designed for the individual soldier in the field and using the same filter media, was built and tested in the laboratory. Using the canister intermittently wet-dry-wet-dry appears to be workable and produces a satisfactory water quality. (Modified author abstract)