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Full-Text Articles in Engineering

Alkali-Silica Reactivity Of Mortars Containing Natural Pozzolan, Arash Kian Dec 2019

Alkali-Silica Reactivity Of Mortars Containing Natural Pozzolan, Arash Kian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali-silica reactivity is one of the most recognized deleterious phenomena in Portland cement concrete resulting in cracks, spalling, and other deleterious mechanisms.

The aim of this study was (i) to assess the extent of reactivity of the aggregates, quarried from seven different sources, suspected of being conducive to ASR, and (ii) to compare the effectiveness of industrial (Class F fly ash) and natural pozzolans in mitigation of alkali-silica reactivity of the studied aggregates. To this end, seven aggregate sources, four natural pozzolan sources, and one source of Class F fly ash were used. ASTM Type V Portland cement was replaced …


Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena Dec 2019

Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena

UNLV Theses, Dissertations, Professional Papers, and Capstones

The strategic planning objectives for a novel Bike Sharing Systems (BSS) are to locate the BSS stations, size the stations, and determine the bicycle fleet size, among others. Current guidelines to design BSS programs are tailored to city centers with large coverage areas and high bicycle to population ratios, and thus not directly transferable to a university setting. An ordered probit model was created using data from a university online stated preference survey to determine the key factors that affect the uptake rates for the UNLV BSS program and to estimate the potential demand. The demand analysis was incorporated into …


Impact Of Design Cost Percentage On Cost Growth, Schedule Growth, And Construction Intensity Of Road Construction Projects, Elina Prajapati Dec 2019

Impact Of Design Cost Percentage On Cost Growth, Schedule Growth, And Construction Intensity Of Road Construction Projects, Elina Prajapati

UNLV Theses, Dissertations, Professional Papers, and Capstones

The performance of construction projects is measured in terms of cost and schedule variation. Studies have identified that such variations are mainly due to design changes, which are more frequent on projects executed through the design-bid-build (DBB) delivery method. Thus, the design factor is identified as one of the major parameters affecting the performance of DBB projects. Despite the majority of road projects being constructed following the DBB method, the impact of design cost on the performance of road projects has not been sufficiently studied yet. Therefore, this study focuses on determining the effect of design cost on the performance …


Application Of Data-Driven And Process-Based Modeling Approaches For Water Quality Simulation In Lakes And Freshwater Reservoirs, Ali Saber Sichani Dec 2019

Application Of Data-Driven And Process-Based Modeling Approaches For Water Quality Simulation In Lakes And Freshwater Reservoirs, Ali Saber Sichani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lakes and freshwater reservoirs often serve as the primary drinking and irrigation water sources for surrounding communities. They provide recreational and tourism opportunities, thereby promoting the prosperity of neighboring communities. Reliable estimates of water quality in lakes and reservoirs can improve management practices to protect water resources.

Seasonal water temperature and solar shortwave radiation variations, and their subsequent interactions with water column aquatic life, combined with seasonal variations of mixing intensity throughout the water column, result in variations of water quality constituents with depth during the annual cycle. The complexity of these variations entails the use of advanced water quality …


Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer Dec 2019

Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Structural health monitoring (SHM) of an instrumented structure provides numerous benefits when assessing the long-term condition of the structure against degradation, or the short-term condition after an extreme event, such as an earthquake. The Nevada Department of Transportation (NDOT) has an interest in expanding the use of SHM for such assessments. Accordingly, the objective of the current study is to develop and implement a permanent SHM system for the Galena Creek Bridge, the largest concrete cathedral arch bridge in the world, to monitor its response to routine traffic and seismic activity. Completed in 2012, the bridge connects Reno and Carson …


Examining The Effectiveness Of A 4d Schedule And A Virtual Reality Model On A Modular Project: Unlv Solar Decathlon Case, Rajarshi Ghimire Dec 2019

Examining The Effectiveness Of A 4d Schedule And A Virtual Reality Model On A Modular Project: Unlv Solar Decathlon Case, Rajarshi Ghimire

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of a 4D schedule as technological advancement has brought significant improvement to the planning and execution of construction projects, through visualizing stepwise construction progress, following a sequence of pre-planned activities, and finalizing a baseline schedule with necessary changes. Moreover, the application of virtual reality (VR) to create interactive 3D models of a planned structure has made it possible to make a detailed planning of any construction project. Because of these benefits, the use of 4D schedules and VR in the construction industry has increased drastically, leading to improved planning and execution. However, past studies have given little attention …


Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier Dec 2019

Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this work was to evaluate the utility of bench scale sand tank experiments at assessing permeable reactive barrier (PRB) design. Our criteria for meeting this goal was that differences between PRB designs could be identified solely by measuring concentration in outflow from the sand tank models. For our PRB designs (funnel-and-gate, staggered wells, and parallel bars), numerical simulations clearly showed that PRB design had a quantifiable effect on outflow concentration, provided that the solute reacted with the PRB materials. Conversely, use of a conservative (non-reactive) solute did not allow us to discern between PRB design alternatives. Employing …


Development Of Natural Perlite Based Concrete For Sustainable Construction, Seyedmahmoud Motaharikarein Dec 2019

Development Of Natural Perlite Based Concrete For Sustainable Construction, Seyedmahmoud Motaharikarein

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study aimed to partially replace Portland Cement (PC) with environmentally friendly binders capable of improving the longevity of concrete. The new binders consisted of different proportions of natural pozzolan (perlite) with various fineness and particle size distributions. A step-by-step research program was designed to: (1) discover the optimum fineness of perlite powder and its optimum replacement level with cement; (2) investigate the rheological properties of the perlite-containing mixtures, and examine whether this binder can be used in selfconsolidating concrete; and (3) assess the weaknesses of the new binder, and improve its deficiencies by using nanomaterials such as nano-silica. The …


Design Of Efficient Carbon-Based Adsorbents For The Removal Of Organic And Inorganic Water Contaminants, Sayedeh Soroosh Mortazavian Dehkordi Dec 2019

Design Of Efficient Carbon-Based Adsorbents For The Removal Of Organic And Inorganic Water Contaminants, Sayedeh Soroosh Mortazavian Dehkordi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Granular activated carbon (AC) and biochar (BC) are two carbon-based adsorbents commonly used for water and wastewater treatment. However, these adsorbents have drawbacks that suppress their aqueous contaminants removal efficiency. Their major disadvantages are that AC has low selectivity and reusability potential, and BC has a hydrophobic nature.

The scope of this dissertation is to enhance the performance of commonly-used carbon-based adsorbents for the removal of organic and inorganic water contaminants and to understand the interactive mechanism of contaminants’ ions/molecules with adsorbents. Hexavalent chromium (Cr(VI)) and trichloroethylene (TCE) are two types of inorganic and organic water contaminants, respectively, which are …


Evaluation Of Titanosilicate Materials For The Sorption Of Cesium And Strontium From High Level Wastes, Matheus Tolentino Lauar Dec 2019

Evaluation Of Titanosilicate Materials For The Sorption Of Cesium And Strontium From High Level Wastes, Matheus Tolentino Lauar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Treatment of high-level waste (HLW) stored in the U.S. Department of Energy (U.S. DOE) sites of Hanford and Savannah River involves the separation of radioactive cesium (137Cs) and strontium (90Sr). Challenges in treating the liquid HLW includes high alkalinity or acidity, and high salt content, many orders of magnitude above Cs and Sr concentrations. Ion exchange is the preferred process for removing these compounds, due to the availability of selective media and large volume-processing capacity by column operations. The crystalline silicotitanate (Na2Ti2O3SiO4·2H2O), i.e. CST, which structure is analog to the mineral sitinakite, is considered the reference material for this application. …


Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy Dec 2019

Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy

Civil Engineering ETDs

Culverts are water conveyance structures, typically used to allow water flow and maintain a balance between the flow streams without interrupting structures such as highways and bridges. Corrugated metal pipes (CMPs) have been used as culverts in North America since the 1950s because of their low cost and simple construction method. Today, the corrosion of CMPs is a major problem faced by all U.S. Departments of Transportation. There is an urgent need to provide an efficient solution, one that is corrosion-resistant, to retrofit thousands of corroded CMPs across the country. High specific strength, high strength to weight ratio, corrosion resistance, …


Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol Dec 2019

Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol

Electronic Thesis and Dissertation Repository

Urban building arrangements such as packing density, orientation and size are known to influence the microclimate surrounding each building. Studies on the impact of urban microclimatic changes on convective heat transfer coefficient (CHTC) from a stock of buildings, however, have been rare in surveyed literature. The present study focuses on numerical and analytical investigation of CHTC from building-like models with homogeneous set of equal and unequal planar and frontal densities. Consequently, the study discusses the CHTC response in relation to broader changes in the urban surface form. Part of the process involves the development of a simplified one-dimensional semi-analytical CHTC …


Spatial And Temporal Characteristics Of Temperature-Precipitation Covariability Across Canada In A Changing Climate, Harsimrenjit Singh Dec 2019

Spatial And Temporal Characteristics Of Temperature-Precipitation Covariability Across Canada In A Changing Climate, Harsimrenjit Singh

Electronic Thesis and Dissertation Repository

Changes in the regional characteristics of temperature and precipitation can intensify the occurrence and severity of extreme events such as rain-on-snow induced flooding, droughts and wildfires. Analyzing these climate variables in isolation without considering their interdependencies might result in severe underestimation of their combined effects. In this study, copula functions are used to describe the joint behaviour of temperature and precipitation across Canada over a historical period of 1910-present using observations and further till the end of the 21st century using three large ensembles of regional climate models. Moreover, given the lack of observation data over Canada, gridded datasets are …


Rapid Characterization Of Dissolved Organic Matter And Precursors To Disinfection By-Products By Fluorescence Technique, Taha Marhaba Dec 2019

Rapid Characterization Of Dissolved Organic Matter And Precursors To Disinfection By-Products By Fluorescence Technique, Taha Marhaba

Sustainability Seminar Series

Natural organic matter (NOM) in the environment today does not only come from humic sources, but also from non-humic or synthetic sources. The typical total organic carbon (TOC) analysis has been typically used as an aggregate measure of NOM in water. NOM from surface water sources were isolated and fractionated by resin adsorption techniques into hydrophobic acid, hydrophobic neutral, hydrophobic base, hydrophilic acid, hydrophilic neutral and hydrophilic base. The Spectral Fluorescent Signatures (SFS) technique through a database of spectral characteristics specific to each fraction was developed for the identification of the six NOM fractions. Among the main advantages of the …


High Strain Dynamic Test On Helical Piles: Analytical And Numerical Investigations, Mohammed Fahad Alwalan Dec 2019

High Strain Dynamic Test On Helical Piles: Analytical And Numerical Investigations, Mohammed Fahad Alwalan

Electronic Thesis and Dissertation Repository

Helical piles are currently considered a preferred foundation option in a wide range of engineering projects to provide high compressive and uplift resistance to static and dynamic loads. In view of the large capacity of large diameter helical piles, there is a need to determine their capacity using accurate and economically feasible testing techniques. The capacity of piles is usually determined by conducting a Static Load Test (SLT). However, the SLT can be costly and time consuming, especially for large capacity piles. The High Strain Dynamic Load Test (HSDT) evaluates the pile capacity using dynamic measurements generated through subjecting the …


Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi Dec 2019

Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi

Civil and Environmental Engineering and Construction Faculty Research

Study region: Sacramento San Joaquin River Basin, California Study focus: The study forecasts the streamflow at a regional scale within SSJ river basin with largescale climate variables. The proposed approach eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962–2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors …


Application Of Bayesian Networks To Integrity Management Of Energy Pipelines, Wei Xiang Dec 2019

Application Of Bayesian Networks To Integrity Management Of Energy Pipelines, Wei Xiang

Electronic Thesis and Dissertation Repository

Metal-loss corrosion and third-party damage (TPD) are the leading threats to the integrity of buried oil and natural gas pipelines. This thesis employs Bayesian networks (BNs) and non-parametric Bayesian networks (NPBNs) to deal with four issues with regard to the reliability-based management program of corrosion and TPD. The first study integrates the quantification of measurement errors of the ILI tools, corrosion growth modeling and reliability analysis in a single dynamic Bayesian network (DBN) model, and employs the parameter learning technique to learn the parameters of the DBN model from the ILI-reported and filed-measured corrosion depths. The second study develops the …


Effect Of Incorporating Pottery And Bottom Ash As Partial Replacement Of Cement, Bassam A. Tayeh, Doha M. Alsaffar, Lawend K. Askar, Asmahan Issa Jubeh Dec 2019

Effect Of Incorporating Pottery And Bottom Ash As Partial Replacement Of Cement, Bassam A. Tayeh, Doha M. Alsaffar, Lawend K. Askar, Asmahan Issa Jubeh

Karbala International Journal of Modern Science

This study addressed the environmental constraints in cement produc­tion. Ordinary Portland cement (OPC) was replaced with pottery powder (PP, produced by grinding locally available pottery) and bottom ash (BA) at 10%, 20% and 30% of cement mass. Moreover, 4% calcium chloride solution (CaCl2.2H2O) was used as mixing water. Material properties, such as standard consistency, setting time and compressive strength, were measured with different percentages of OPC replacement with PP and BA. Results indicated that the replacement with PP and BA increased the water demand to achieve the standard consistency. These results revealed that the strength evolution …


Lidar Assessment To Monitor Bridge Response Under Live And Dead Loads, Daniel Watson Dec 2019

Lidar Assessment To Monitor Bridge Response Under Live And Dead Loads, Daniel Watson

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Understanding how a bridge structure responds to various loads in a time and resource-efficient approach is vital in characterizing bridge health. Bridge health monitoring is an evaluation of the structural condition and performance, which optimizes limited transportation budgets by prioritizing the bridges that are in the most need for retrofit or replacement. Identifying and remedying issues will mitigate long-term problems and ensure that the bridge remains open to service for all legal loads. In contrast, health monitoring and load rating will determine if a bridge can only carry traffic up to a certain weight or speed, requiring a bridge load …


College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas Dec 2019

College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …


Numerical Simulations Of The Hall–Petch Relationship In Aluminium Using Gradient-Enhanced Plasticity Model, Yooseob Song, Jaeheum Yeon, Byoungjoon Na Dec 2019

Numerical Simulations Of The Hall–Petch Relationship In Aluminium Using Gradient-Enhanced Plasticity Model, Yooseob Song, Jaeheum Yeon, Byoungjoon Na

Civil Engineering Faculty Publications and Presentations

+e Hall-Petch relation in aluminium is discussed based on the strain gradient plasticity framework. +e thermodynamically consistent gradient-enhanced flow rules for bulk and grain boundaries are developed using the concepts of thermal activation energy and dislocation interaction mechanisms. It is assumed that the thermodynamic microstresses for bulk and grain boundaries have dissipative and energetic contributions, and in turn, both dissipative and energetic material length scale parameters are existent. Accordingly, two-dimensional finite element simulations are performed to analyse characteristics of the Hall–Petch strengthening and the Hall–Petch constants. +e proposed flow rules for the grain boundary are validated using the existing experimental …


Diffusion And Uniformity Of Recycled Asphalt In Pavements, Baoshan Huang Dec 2019

Diffusion And Uniformity Of Recycled Asphalt In Pavements, Baoshan Huang

Abbett Distinguished Seminar Series

Asphalt pavements covers over 93 percent of the paved roads in the United States. The use of recycled asphalt into pavement maintenance and construction has been a common practice. However the lack of understanding of the interaction between recycled and virgin asphalt poses a change on the efficient use of recycled asphalt, and often causes pavement premature failures. The present study addressed some fundamental aspects associated with the beneficial use of recycled asphalt into asphalt paving mixtures: 1) how much recycled asphalt can be mobilized into a uniform asphalt coating in the mixture? and 2) will the mobilized old asphalt …


Simulation Training And Route Optimization For Bridge Inspection, Sushil Louis Dec 2019

Simulation Training And Route Optimization For Bridge Inspection, Sushil Louis

INSPIRE Archived Webinars

Since the 1970s, simulation training has developed opera­tional trainers for a variety of complex systems from pilot flight simulations to cultural awareness training simulations. When connected to the real world, such simulation training interfaces can drive real vehicles and systems. We have been building a Simulation Training And Control System (STACS) for autonomous bridge inspection that uses a simulated world to train inspectors to control a heterogeneous group of robots. The objective is that, once trained, inspectors can use the same STACS interface used in training to control multiple real robots simultaneously during a bridge inspection task. We first built …


Modeling The Effects Of Distribution System Topology On Water Quality, Chun-Ying Chao Dec 2019

Modeling The Effects Of Distribution System Topology On Water Quality, Chun-Ying Chao

McKelvey School of Engineering Theses & Dissertations

Inadequate treatment of drinking water causes the formation of disinfection by-products and the regrowth of harmful microbial species. Various studies have addressed the problem of water quality monitoring, but very few have employed topological analysis, a valuable mathematical tool widely applied in biological, business, and social research. This thesis examines the relationship between the topological properties of water distribution systems and water-quality models. In particular, the research proposes a novel framework for mapping network topological attributes to water-quality models. This research adopts topological metrics to assess the accuracy of the predictions of chlorine concentrations in dead ends. It examines four …


Energy & Carbon Neutral Nyc, Evan Banks, Elena Zimareva, Elena Malysheva Dec 2019

Energy & Carbon Neutral Nyc, Evan Banks, Elena Zimareva, Elena Malysheva

Publications and Research

In 2016, the world's leading countries signed the Paris Agreement which focused on reducing anthropogenic climate change on the planet. On May 2019, New York State and New York City declared its own ambitious goals aimed at decarbonizing the city and restricting the state’s energy use to relying completely on renewables.

Some of these goals specifically target infrastructure in the city since estimates cite buildings as accounting for nearly 70% of New York’s energy use. The main law of New York’s Climate Policy, Local Law 97, requires all buildings over 25,000 sq ft to reduce their CO2 footprint by 40% …


Optimizing On-Street Parking Supply With Analytical Models, Chawalit Tipagornwong Dec 2019

Optimizing On-Street Parking Supply With Analytical Models, Chawalit Tipagornwong

Dissertations and Theses

Commercial vehicles are crucial for the urban economy, but they generate negative impacts as well. This leads to restrictions such as a reduction in the number of loading zones. The result is that commercial drivers spend a significant amount of time searching for available loading zones. To avoid searching for parking, some commercial drivers double park, which causes traffic congestion. Therefore, the number of loading zones should be set properly. Since a curb is allocated between both loading zones and parking spaces, both parking types have to be considered. Many on-street parking management strategies have been implemented, including pricing meter …


Comprehensive Inspection On The Experimental Ferritic Stainless Steel By Means Of Transmission Electron Microscopy And Neutron Diffraction Techniques, Parikin Parikin, Mohammad Dani, Riza Iskandar, Aziz Khan Jahja, Andon Insani, Joachim Mayer Dec 2019

Comprehensive Inspection On The Experimental Ferritic Stainless Steel By Means Of Transmission Electron Microscopy And Neutron Diffraction Techniques, Parikin Parikin, Mohammad Dani, Riza Iskandar, Aziz Khan Jahja, Andon Insani, Joachim Mayer

Makara Journal of Technology

The field of physical metallurgy is one of the primary beacons that guide alloy developments for multipurpose materials such as the in-core structure materials for pressure vessel components and heat exchangers. The surface microstructure of new ferritic steel with significant local constituent materials was characterized by high resolution powder neutron diffractometer (HRPD) and transmission electron microscope (TEM), combined with the energy dispersive X-ray spectroscopy (EDX). The alloy contains73% Fe, 24% Cr, 2% Si, 0.8% Mn, and 0.1% Ni, in %wt. The charge materials were melted by the casting techniques. The neutron diffractograms obtained shows five dominant diffraction peaks at (110), …


Acute Toxicitystudy Of Choline Based Ionic Liquids Towards Danio Rerio Fish And The Aggregation Behavior Of Their Binary Mixtures, Mansoor Ul Hassan Shah, Nasruddin Nasruddin, Suzana Bt Yusup, Muhammad Moniruzzaman Dec 2019

Acute Toxicitystudy Of Choline Based Ionic Liquids Towards Danio Rerio Fish And The Aggregation Behavior Of Their Binary Mixtures, Mansoor Ul Hassan Shah, Nasruddin Nasruddin, Suzana Bt Yusup, Muhammad Moniruzzaman

Makara Journal of Technology

Marine oil spills are effectively controlled by chemical dispersants. However, the toxicity associated with it reduce its employment in marine environment. To overcome this limitation, the acute toxicity of choline based ionic liquids was evaluated as a potential low toxic variant for oil spill remediation. Further, the aggregation behavior of the individual as well as their binary mixtures was also evaluated by employing tensiometry technique. The half-lethal concentration, LC50on zebrafish (Danio rerio) of three choline based ionic liquids showed that the studied ionic liquids (ILs) fall in the range of “practically nontoxic” ( 100-1000 mg L-1).Various micellar properties showed that …


Study On Antibacterial Of Chitosan/Hydroxyapatite Doped Magnesium Composite As A Material For Bone Graft Applications, Andromeda Dwi Laksono, Teodoro A. Amatosa, Jr., Hilda Pebrianti Octaviana Sitorus, Wentika Putri Kusuma Asih, Sulistijono Sulistijono Dec 2019

Study On Antibacterial Of Chitosan/Hydroxyapatite Doped Magnesium Composite As A Material For Bone Graft Applications, Andromeda Dwi Laksono, Teodoro A. Amatosa, Jr., Hilda Pebrianti Octaviana Sitorus, Wentika Putri Kusuma Asih, Sulistijono Sulistijono

Makara Journal of Technology

Hydroxyapatite (HAp) is one of the constituent minerals of bone and teeth, that has been widely used for synthesizing bone graft. Due to the limitation on properties of the hydroxyapatite, it is doping with Magnesium (HAp-Mg). The addition of Chitosan (Chi) was expected to improve the antibacterial properties of HAp-Mg. The present research aims to study the influence of Chitosan with 0, 5, 15, and 25 wt% addition on biocompatibility properties of Chi/HAp-Mg composite. HAp-Mg was synthesized using the sol-gel method; meanwhile, Chi/HAp-Mg composite was manufactured by mixing Chitosan in acetic acid, and HAp-Mg was added into the mixture. The …


Evaluation Of Primal-Dual Splitting Algorithm For Mri Reconstruction Using Spatio-Temporal Structure Tensor And L1-2 Norm, Mia Rizkinia, Masahiro Okuda Dec 2019

Evaluation Of Primal-Dual Splitting Algorithm For Mri Reconstruction Using Spatio-Temporal Structure Tensor And L1-2 Norm, Mia Rizkinia, Masahiro Okuda

Makara Journal of Technology

Magnetic resonance imaging (MRI) is an essential medical imaging technique which is widely used for medical research and diagnosis. Dynamic MRI provides the observed object visualization through time and results in a spatiotemporal signal. The image sequences often contain redundant information in both spatial and temporal domains. To utilize this characteristic, we propose a spatio-temporal reconstruction approach based on compressive sensing theory. We apply spatio-temporal structure tensor using nuclear norm, in addition to the wavelet sparsity regularization. The spatio-temporal structure tensor is a matrix that consists of gradient components of the MRI data w.r.t the spatial and temporal domains. For …