Analisis Kinerja dan Kualitas Hasil Kompresi pada Citra Medis Sinar-X Menggunakan Algoritma Huffman, Lempel Ziv Welch dan Run Length Encoding

Technological progress in the medical area made medical images like X-rays stored in digital files. The medical image file is relatively large so that the image needs to be compressed. The lossless compression technique is an image compression where the decompression results are the same as the original or no information lost in the compression process. The existing algorithms on lossless compression techniques are Run Length Encoding (RLE), Huffman, and Lempel Ziv Welch (LZW). This study compared the performance of the three algorithms in compressing medical images. The result of image decompression will be compared to its performance in the objective assessment such as ratio, compression time, MSE (Mean Square Error) and PNSR (Peak Signal to Noise Ratio). MSE and PSNR are used for quantitative image quality measurement for subjective assessment assisted by three experts who will compare the original image with the decompression image. Based on the results obtained from the objective assessment of compression performance of RLE algorithm showed the best performance by yielding ratio, time, MSE and PSNR respectively 86,92%, 3,11ms, 0 and 0db. For Huffman, the results can be 12.26%, 96.94ms, 0, and 0db respectively. While LZW results can be in sequence -63.79%, 160ms, 0.3 and 58.955db. For the results of the subjective assessment, the experts argued that all images can be analyzed well

Geology and the effect of compaction on base material disposal for the stability of coal disposal slopes in South Kalimantan, Indonesia

A mining activity generally removes overburden to extract minerals. Therefore, a certain area is needed to place the overburden material. One of the parameters that can affect the stability of the disposal is the base or the foundation of the disposal area which will later be stockpiled. This study is observe influence of base disposal to the stability of slope. Based on the lithological characteristics and observations of the outcrop, the writer arranges the stratigraphy of the study area in order to determine the stratigraphic arrangement and the distribution of the rock units laterally. In general, the study area is dominated by quartz sandstone, claystone, conglomerate and loose material from older rocks. The stratigraphic sequence of the study area from old to young includes Warukin Sandstone Unit (Tmw), Dahor Layang Member Conglomerate (TQdt) and Dahor Sandstone Unit (TQd). In general, the research area is included in the structural landform unit with geomorphological control that influences the tectonic process (endogenous). Based on the results of the study, there was a significant increase related to the stability of the coal disposal slope with compaction efforts carried out on the base material

Hydraulic conductivity of compacted clay liners moisture-conditioned and permeated with saline coal seam gas water

The effects on the hydraulic conductivity of compacted clays, commonly used for lining coal seam gas (CSG) water storage ponds, of moisture conditioning and permeating with CSG water are investigated. Four kaolinite-dominant clays were mixed with CSG and deionised waters, compacted to varying degrees at different gravimetric moisture contents. The compacted specimens were subjected to 100 kPa hydraulic loading with CSG or deionised waters in compaction mould permeameters, and 100 kPa applied stress in oedometers, with the specimens placed in a bath of CSG or deionised water to match the water used to prepare the specimens. The 100 kPa loading represented the expected maximum pond water depth. The test results show that the hydraulic conductivity of clay specimens moisture-conditioned and permeated with both CSG and deionised waters decreased with time due to rearrangement of the clay particles. At the end of the tests with CSG and deionised waters, the clay specimens were found to have very low hydraulic conductivities of the order of 1E-11 m/s. The hydraulic conductivity values measured using the compaction mould permeameters were found to be reasonably comparable to those calculated from oedometer test data

Effects of saline coal seam gas water on consistency limits, compaction characteristics and hydraulic conductivities of clays used for liners

Four kaolinite-dominant clays were moisture-conditioned with coal seam gas (CSG) water (CW) and deionized water (DW) and their consistency limits and compaction characteristics were compared. Further, two of the four clay samples were moisture-conditioned with CW, compacted in compaction mould permeameters and permeated with DW, CW and brine water (BW) under a 100 kPa hydraulic loading, simulating a pond water depth of 10 m in the field. The test results show that CW tended to increase the liquid and plastic limits and decrease the compaction densities of the clay samples. The hydraulic conductivities of the clay samples tended to decrease with decreasing concentration of salt and increasing pH value of the permeating waters. The hydraulic conductivities of the clay samples that were permeated with DW and CW were about one order of magnitude lower than those permeated with BW. At pH values above the isoelectric point of the edges (IEP) of the clay particles, the hydraulic conductivities of the clay samples tended to increase with increasing concentration of salt of the permeating water. The changes in the index and hydraulic parameters of the clay samples were attributed to changes in the net interparticle forces and in the associated clay structure

Understanding the stability of Samanea saman trees through tree pulling, analytical calculations and numerical models

There have been several cases of tree failure in Singapore. Many studies have shown that soil properties and root architecture of trees are important factors that govern tree stability. Twenty Samanea saman trees were planted in different soil media, which were original in-situ soil, top soil, mixture of 50% granite chips and 50% top soil, and mixture of 80% granite chips and 20% top soil. The objectives of this study were to investigate tree overturning processes and also to compare the results of tree pulling tests with results from an analytical calculation and numerical modeling for different soil types. The results showed that stability of the trees were not governed by the shear strength of the soil. Factors that affected tree stability included cross-sectional area of the roots and root plate area. Tree pulling test and numerical modeling results showed that there were two modes of failure which occurred when a tree was overturned. The first mode was the shear failure of soil and the second was a combination of shear failure of soil and root breakage. The maximum overturning force obtained from the tree pulling test was in the same order of magnitude as the maximum overturning forces obtained from the analytical calculation and numerical modeling.Accepted versio

CO2CRC CCS Cost Reduction Project: Solvent Precipitation System

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A Review on Adaptive Methods for Structural Control

Adaptive control algorithms are widely used in many technical fields like aeronautics and robotics for controlling systems whose characteristics vary with time or are uncertain. In the last decades, with the diffusion of active and semiactive control applications in civil engineering, adaptive methods started to be adopted for structural control. This paper provides an up-to-date survey on strategies currently available for adaptive control and a literature overview of solutions examined until today for structural applications