In the Gondang area, Bojonegoro, East Java, there were manifestations of hot springs and mud pools. This research will use several variations of the value in the continuation-up filter and one of them will be selected to continue as a model. Based on the data processing results, it is known that the upward continuation value used is 100mdatum with the magnetic strength value in the regional anomaly from 106.5 nT to 509.0.
This picture can be seen through variations in the distribution of rocks' sensitivity, namely the ability to accept the magnetic properties of the Earth's magnetic field. The physiography of the study area is the Kendeng zone in the south, which consists of rugged hills with steep slopes. Low intensity values (usually blue) are found in the manifestation areas such as mud pools, Selogajah and also Banyukuning.
It is clear that the attenuation of shallow source anomalies in the upward continuation process enables a clearer or improved view of deeper anomalous sources (Blakely, 1996). In the model above (figure 10), it is assumed that the susceptibility value of the upper layer is breccia volcanic rock, which can be found in the upper layer at the study site (Kendeng zone) marked in blue. The green color or inversion model can be interpreted as a Kalibeng formation with susceptibility value of -0.0061 to 0.0012.
Likewise, the Kerek Formation as the oldest formation in the study area can be seen more clearly in the geological section by comparing the inversion model at the susceptibility value of -0.0033 SI.
THE APPLICATION OF COMBINATION OF SOLID BOXES AND AIR BAGS TO SUPPORT THE
UNSINKABLE SMALL PASSENGER BOAT
During the sea trial, fifteen passengers and equipment were placed on board and water was filled in the boat. The use of side floats will increase the buoyancy and stability of the boat. Other massive boxes are enclosed spaces attached to the bow and stern of the boat.
The airbags are formed from expanded bags installed on board and outside the boat. The airbags are stored in small boxes on board and outside the boat. METHODOLOGY. The boat model was built in three phases, namely the inner template, the model template and the model.
The general arrangement of the boat In addition, the floats were attached to the side outside the boat (Figure 5). The compressed tanks carry the air into the plastic bags inside and outside the boat. The boat components include the weight and volume of the boat, sturdy boxes and airbags.
Six scenarios were run to find the configuration of solid boxes and airbags to prevent the boat from sinking. The first scenario presented for the boat was at the designed draft due to normal loading condition. In scenario 2, the boat is provided with solid boxes and loaded with passengers and incoming water.
Similar to scenario 2, scenario 3 added internal airbags, but cannot avoid sinking the boat. Choosing the correct configuration of rigid boxes and airbags will provide buoyancy and righting moment to prevent the boat from sinking and capsizing. 2010), Intact Stability - The Principles of Naval Architecture Series, The Society of Naval Architects, SNAME, Jersey City, New Jersey Parametric Design - Ship Design and Construction, Chapter 11, Vol.
GNSS METEOROLOGY AND LAND SUBSIDENCE OF HEAVY RAINFALL IN JAKARTA ON JANUARY 1, 2020
DATA AND METHODS 1 GNNS data set
- Software goGPS
- Land Subsidence in Jakarta
The primary GNSS data format used in this study is the Receiver Independent Exchange (RINEX) format. Then, the RINEX files were processed to estimate tropospheric parameters using a sophisticated open source GNSS software called goGPS, version 1.0 Beta, from Geomatics Research and Development s.r.l. There were at least 5 GNSS stations in the flood area identified and operated by BIG in the INACORS network.
Data were used for 7 days, from December 29, 2019 to January 4, 2020 to capture the phenomenon including changes in several days before and after the flood and heavy rain. High PWV brings intense rainfall and record rainfall data from BMKG on January 1, 2020 has been associated with high PWV values. Vertical crustal motions were also analyzed using coordinates obtained from RINEX data analysis of the goGPS software.
Realini (with contributions from various thesis works of master students) since 2007 at the Geomatics Laboratory of the Polytechnic of Milan, Como Campus. It is specifically designed to improve the positioning accuracy of low-cost GNSS devices through relative positioning and the Kalman filtering technique. The project has been open for collaborations since its release and has received support and code contributions from users working in both academia and business companies in various countries (including Italy, Japan, Switzerland, Spain and Germany).
Jakarta is vulnerable to further land subsidence, especially when heavy rains occur and rainwater pools cause a flood. This study discussed the temporary land subsidence related to the occurrence of heavy rain on January 1, 2020 using GNSS data analyzed with the open source software goGPS. Figure 2, Land subsidence in several coastal cities in different countries, including Jakarta, Indonesia, from 1920 to recent years (Andreas et al., 2019).
RESULT AND DISCUSSIONS
- Determination of PWV values at 5 INACORS stations
- Comparison of PWV INACORS with Jakarta Radiosonde Station
- Crustal movement analysis, GNSS station (INACORS-BIG)
3, the PWV values at the five GNSS stations show similar patterns, despite the inter-station average of ~30 km. The PWV values appear to increase in the middle of the day on December 30, 2019 and the peak occurred at the end of the day on December 31, 2019. At the end of the day the PWV increased again, but not as high as the first peak .
Next, this information was compared with the hourly PWV values at GNSS stations shown in Fig. This suggests that monitoring GNSS meteorology data from INACORS is useful as a meteorological observation. Hourly PWV values at 4 INACORS GNSS stations, BAKO, CTGR, CJKT and CBTU stations during the day on 31 December 2019.
To compare GNSS-PWV values with those from other sensors, PWV data were obtained from radiosondes at BMKG, Jakarta. BMKG serves not only as a GNSS station, but also as a radiosonde station in Jakarta under the name station WIII. The correlation between the two PWV values is not that high, probably due to the distance between the two stations.
Nevertheless, the PWV of GNSS stations can complement the radiosonde data with their high spatial and temporal resolution. Comparison of PWV values between GNSS-PWV at CJKT stations estimated every 30 seconds (orange curve) and radiosonde PWV recorded every 6 hours at the WIII station. Figure 7, Vertical position time series over a period spanning 20 days for the 5 GNSS stations in the region flooded by the January.
The vertical positions of GNSS stations were estimated to study the vertical crustal displacements between the floods on 1 January 2020 and the heavy rains on 31 December 2019. This study used GNSS data in RINEX format with supporting satellite ephemeris data. From the 5 GNSS-INACORS stations located in the flood area of Jakarta, the data from the BAKO station on January 1, 2020 could not be processed because there was an interruption during the data acquisition process.
CONCLUSION
On the other hand, CJKT was close to the coast and not included in the flooded area. These results suggest that subsidence due to floodwater loading is quite nonuniform in space, and a dense network will be needed to fully understand the crustal response to the surface stormwater loading in Indonesia. Vapor inhomogeneity using the Japanese nationwide GPS array and its potential for convective precipitation prediction.
COMPUTATIONAL ANALYSIS ON HEAVE AND PITCH MOTIONS PERFORMANCE OF A HYDROFOIL SHIP
CHARACTERISTIC OF SPENT BLEACHING EARTH SUBSTITUTION IN LIMESTONE
AS LANDFILL MATERIAL
CBR (California Bearing Ratio) Laboratory Testing
The test method of replacement of SBE in limestone was carried out for several variations in the composition of SBE - limestone mixture. The test methods are intended to obtain physical and mechanical properties of the material based on 4 test methods i.e. the sieve test, Atterberg test, Proctor test and CBR test. The result of the sieve test showed that the distribution of SBE grain sizes (more than 90%) passes from sieve number 200.
Because the SBE acts as a filler in the mix, replacement in the limestone does not affect the gradation of the limestone. Even replacement of SBE up to 50% in the mixed composition does not change the size distribution of limestone grains. For landfill applications, in terms of grain size distribution, SBE replacement can be used in limestone up to 50% of its weight, but the best gradation is shown at 30% SBE replacement.
Compaction is intended to improve soil quality by increasing soil shear strength, reducing settlement, reducing permeability, and controlling changes in relative volume due to soil shrinkage-swelling. Based on the test results (Table 3), the substitution of SBE in limestone shows a value that has a tendency to decrease compared to the initial value of the material (LM 100%), but the quality of the material is still in the category of good for landfills. The SBE substitution CBR value of the resulting limestone is greater than the CBR value of the initial limestone, but this condition is inversely proportional to the maximum dry weight value and the optimum water content is much lower than the initial limestone (Figure 3). ).
As shown in Figure 3, the best CBR value is obtained at 30% SBE substitution in limestone, resulting in a CBR value of 43.20. SBE replacement in limestone as a landfill material can be used up to 30% by weight based on the test result. Substitution of SBE in limestone does not change the grain size of the composite material even up to 50% mass substitution.
However, substitution of SBE up to 50 wt. % in limestone only reduces the dry density value of the limestone by 16%, which is not a significant change in use. Thus, SBE substitution in limestone up to 50% does not significantly change the properties of a limestone-based landfill with moderate efficiency. SBE replacement can increase the CBR value of the mixture by up to 200% or 2 times the original CBR value of the limestone.
