Papers by Keyword: Depth

Abstract: The development of remote sensing technology based on cloud computing is an important concern, especially in providing convenience in processing and storing images for various importance. This can be utilized in hydrographic activities in terms of determining depth values using the Satellite Derived Bathymetry (SDB) method. This research focuses on the utilization of Google Earth Engine (GEE) technology in obtaining depth values using the SDB method with Stumpf and Lyzenga algorithms. The area used in this research is on the island of Bangka Belitung which has different characteristics of waters such water depth, water clarity, and water bottom cover. The results of the research conducted were evaluated with the Indonesian National Standard (SNI) 8202 in 2015 regarding the accuracy of the base map. Depth extraction using 2,662 depth sample data. The results of this study show that the Stumpf model provides a better accuracy value compared to the Lyzenga model at 0 - 10 meters. But at 10-25 meters the Lyzenga model produces a better accuracy value than the Stumpf model. The best correlation value was obtained with the Lyzenga model, which is equal to 0.841 while the correlation value of the Stumpf model is 0.753. The best RMSE was obtained at 1.7 m with a depth range of 0 - 5 m with the Stumpf method. The results of the accuracy evaluation of the two empirical bathymetry models pass the requirements of SNI 8202 of 2015 regarding the Accuracy of the Base Map for making Lingkungan Pantai Indonesia (LPI) and Lingkungan Laut Nasional (LLN) maps at a scale of 1: 50,000 with a 20 m contour interval.

Abstract: The basic facilities in a port consist of shipping channels, berthing area, and turning basins. Those facilities will also be built at Branta Harbor so large ships can enter and dock. Those basic facilities are not yet available due to the lack of appropriate data. The port planning activities require bathymetric data, seabed imageries, tides, and topographic conditions of the port area. It is essential in port planning, which can guarantee the safety of maritime shipping. The depth of Branta Harbor ranges from 0.7 m to 25.2 m. The condition of the seabed is mostly sand, and several submarine pipes, trawl nets, and fishing nets were found in the area, although there were no endangered shipping objects. The shipping channels is designed as a two-way lane with a length of 1,550 m and a width of 200 m. The berthing area is 23 hectares, the emergency area is 11.56 hectares, and the turning basin is 7.06 hectares. The main facilities are designed with a depth of 8 m and must be dredged in the turning basin area and shipping channel. By this planning, it is hoped that the draft of ships that can enter Branta Harbor up to 7 m.

Abstract: CO₂ levels in the world are constantly increasing and have generated a great impact on reinforced concrete structures causing increased carbonation. The phenomenon of carbonation causes corrosion of the reinforcing steel, therefore, reinforced concrete structures present a high risk of corrosion of its reinforcing steel causing the reduction of the useful life of the structure, or in extreme cases, a demolition must be carried out. The objective of the present study is to propose a prediction model for carbonation depth in pure concretes which are not designed for durability (w/c<0.50), but when they are designed for resistance (w/c>0.55). CEB-FIP model presents the limit of serving only for concrete with w/c<0.50, due to this, the present study proposes a model that will help as a reference to estimate the useful life of structures that are built and designed in cities where they do not are exposed to these durability conditions. The modified model for predicting the carbonation depth based on CEB-FIP in pure concrete with high w/c (0.60 and 0.72) uses the parameters of temperature, relative humidity, CO₂ concentration, and water/cement ratio. The objective is to obtain the accuracy of the modified model for predicting the carbonation depth in concrete over the years. For the results, the theoretical data obtained from the modified model was used and a comparison was made with the experimental results obtained from concrete specimens tested inside an accelerated carbonation chamber to find the model's accuracy.

Abstract: The integral-differential equation of the cascade process for ions was solved using the Laplace transform and the method of successive approximations, taking into account the energy loss during the formation of primary-knocked-on atoms (PKA) in a one-dimensional model of an elementary atom. It is shown that the solution includes a cascade-probability function (CPF) for these particles. The main properties of CPF are considered and its graphical dependencies on the depth of registration are presented. It is shown that with the specific ionization loss coefficient k = 0, the FQM turns into the simplest cascade-probability function. When λ₀→ 0, λ₀→∞ and n→∞, the KV-function is equal to 0. The sum of the probabilities for all possible collisions from 0 to ∞ is 1. As the detection depth h increases, for all values of n, the CRF increases, reaches a maximum and then decreases . With increasing n, the curves shift to the right.

Abstract: The use of magnetic Barkhausen noise (MBN) signal to non-destructively characterize the in-depth residual stress state of machined steel was investigated. The effect of the frequency of the magnetic field applied and of analysing the resulting MBN signal in different frequency bands for an in-depth residual stress characterisation is discussed. The effect of the residual stress on each of the parameters derived from the MBN signal is analysed comparing with the result of the XRD method.

Abstract: At present, there are not enough research for the initial collapse pressure and collapsible coefficient of the loess in the country; There are tests for the Jinnan collapsible loess, to study the collapsible coefficient and the initial collapse pressure changes with the depth. The results showed that: When the vertical pressure is 200 kPa , the collapsible coefficient is the largest. The collapsible coefficient decreases with the depth increase. The initial collapse pressure increases with the depth increase.

Abstract: This paper takes the following measures to solve the problem of 3D reconstruction. Camera calibration is based on chessboard, taking several different attitude images. Use corner point coordinates by corner detection to process camera calibration. The calibration result is important to be used to correct the distorted image. Next, the left and right images should be matched to find out the object surface points’ imaging position respectively so that the object depth can be calculated by triangulation. According to the inverse process of projection mapping, we can project the object depth and disparity information into 3D space. As a result, we can obtain dense point cloud, which is ready for 3D reconstruction.

Abstract: In order to maintain the existing concrete structures in a safe and usable state, an overall maintenance management is necessary regarding structure aging from quality management of new construction. Thus, non-destructive testing is needed to estimate the structure damage, defect, or proper construction without damaging the structure. In U.S., there is a standard for non-destructive test (ACI 228.2R-98), and also in Japan, the non-destructive test method and compressive strength estimation manual was prepared by the Architectural Institute of Japan in 1983, and there are active researches in the ground field, but it lacks verification in architecture field. Thus, in this study, a technique that can estimate the depth of concrete column member using the Impact Echo method which is one of the non-destructive test methods shall be reviewed and evaluated for applicability to the architecture field. The specimen was mixed with design strength of 30MPa. The equipment used in testing is Freedom Date Pc Platform Win.TFS 2.5.2 by company Olson of U.S., and the experiment involved leveling the top surface of the concrete member, installing the equipment and applying impact 9 times, and taking the average of the reverberation values obtained. The estimated average depth of concrete column member using Impact Echo method was 304mm for IEC-300, 398mm for IEC-400, and 484mm for IEC-500, and the relative error rate compared to the actual size was 1%~3%. Through this study, the applicability of estimation of depth in concrete column members using impact echo method could be confirmed.

Abstract: An non-vertical stereoscopic 3-D display method by changing the parallax value of the parallax images is proposed. This method is capable of displaying virtual reality with high-immersion sense because the observing depth only depends on the parallax value. An experimental 3-D display system capable of producing high-immersion and virtual reality video images at 45 degree is developed. Furthermore, the effectiveness of the method is demonstrated by using this system.

Abstract: Present situation and guidance ammunition weapon equipment in maintenance system is analyzed, From the strengthening of technical knowledge the existing problems of guidance ammunition support operating system and repair depth are put forward, a complete theoretical system is established, security concept is established in perfect communication platform, a new repair system is established including overall planning of the test and support evaluation of guidance ammunition , to strengthen and improve the guidance ammunition support maintenance work.