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2018

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Articles 331 - 360 of 1644

Full-Text Articles in Electrical and Computer Engineering

Research On Safety Management Of Maritime Autonomous Surface Ships, Kangqun Chen Aug 2018

Research On Safety Management Of Maritime Autonomous Surface Ships, Kangqun Chen

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.


A Study On Reduction Of Harmonic Distortion Caused By Ac Arc Furnaces, Venkata Mani Gadiraju Aug 2018

A Study On Reduction Of Harmonic Distortion Caused By Ac Arc Furnaces, Venkata Mani Gadiraju

LSU Master's Theses

In AC arc furnaces, arc ignition is stabilized by inductors which are connected across its supply lines. They cause power factor degradation in the system. When furnaces are modelled as linear RL load, the arc nonlinearity reduces the impact of this degradation to a significant extent. Furnace Power factor is improved by the DC voltage on the arc. In this research study, power factor of AC furnaces is estimated on the assumption that DC voltage on the arc is constant and furnace operates in steady state. Primary objective of this research was to determine the power factor of the furnace …


From E-911 To Ng-911: Overview And Challenges In Ecuador, Danilo Corral-De-Witt, Enrique V. Carrera, Jose A. Matamoros-Vargas, Sergio Munoz-Romero, Jose Luis Rojo-Alvarez, Kemal Tepe Aug 2018

From E-911 To Ng-911: Overview And Challenges In Ecuador, Danilo Corral-De-Witt, Enrique V. Carrera, Jose A. Matamoros-Vargas, Sergio Munoz-Romero, Jose Luis Rojo-Alvarez, Kemal Tepe

Department of Electrical and Computer Engineering: Faculty Publications

For years, emergency attendance institutions in Ecuador worked separately and not all of them had a 24/7 service, resulting in duplicated efforts, a waste of the scarce resources, and an absence of generalized technology. In 2012, Ecuador created an Integrated Security Service, called ECU 911, to address the need of an emergency service articulating all the first response institutions. The ECU 911 relies on the Enhanced 911 technology, having a countrywide presence. Since then, Ecuador has implemented 16 public-safety answering points and 11 decentralized operative rooms, covering all Ecuadorian territory and serving to a population of about 17 million people. …


Electrical & Computer Engineering News, Georgia Southern University Aug 2018

Electrical & Computer Engineering News, Georgia Southern University

Electrical & Computer Engineering: News & Publications (2014-2023)

  • NSF Funded Research: “Fully Integrated Power and Energy Systems with Multi- Infeed AC/DC Architecture”, By Dr. Masoud Davari


Electrical Characteristics Of Polypropylene Mixed With Natural Nanoclay, Huseyin R. Hiziroglu, Iosif E. Shkolnik Aug 2018

Electrical Characteristics Of Polypropylene Mixed With Natural Nanoclay, Huseyin R. Hiziroglu, Iosif E. Shkolnik

Electrical & Computer Engineering Publications

Polypropylene has been used in radio-frequency capacitors and has also started to be employed in cables as insulation. The objective of this study was to evaluate the electrical properties of polypropylene filled with natural clay as a nano-material. Polypropylene samples having 0%, 2% and 6% natural clay by weight were exposed to 60-Hz sinusoidal voltages at two different rates of rise. The breakdown voltage of each sample was recorded at these different ramp rates. Also, the Root-mean-squared (rms) current was measured as the voltage was increased across the test samples. The important findings of this study were (a) the breakdown …


Automating Variation And Repeater Analysis In Physical Design Of Integrated Circuits, Subrat Mahalik Aug 2018

Automating Variation And Repeater Analysis In Physical Design Of Integrated Circuits, Subrat Mahalik

Dissertations and Theses

Rapid advancement and innovation in semiconductor research have continuously helped in designing efficient and complex integrated circuits in miniature size. As the device technology, is aggressively scaling to improve the device performance, the issues related to device interconnects, power, and reliability have become a major concern for the designers. These challenges make the design and validation of ASIC extremely complicated.

The primary idea of this work is to develop automation tools, to be used in the physical design flows to improve the efficiency of the design flow. The first tool named as variation analysis tool automates the on-chip variation modeling …


Chaos Firefly Algorithm With Self-Adaptation Mutation Mechanism For Solving Large-Scale Economic Dispatch With Valve-Point Effects And Multiple Fuel Options, Yude Yang, Bori Wei, Hui Liu, Yiyi Zhang, Junhui Zhao, Emad Manla Aug 2018

Chaos Firefly Algorithm With Self-Adaptation Mutation Mechanism For Solving Large-Scale Economic Dispatch With Valve-Point Effects And Multiple Fuel Options, Yude Yang, Bori Wei, Hui Liu, Yiyi Zhang, Junhui Zhao, Emad Manla

Electrical & Computer Engineering and Computer Science Faculty Publications

This paper presents a new metaheuristic optimization algorithm, the firefly algorithm (FA), and an enhanced version of it, called chaos mutation FA (CMFA), for solving power economic dispatch problems while considering various power constraints, such as valve-point effects, ramp rate limits, prohibited operating zones, and multiple generator fuel options. The algorithm is enhanced by adding a new mutation strategy using self-adaptation parameter selection while replacing the parameters with fixed values. The proposed algorithm is also enhanced by a self-adaptation mechanism that avoids challenges associated with tuning the algorithm parameters directed against characteristics of the optimization problem to be solved. The …


Obtaining Chemical Selectivity From A Single, Nonselective Sensing Film: Two-Stage Adaptive Estimation Scheme With Multiparameter Measurement To Quantify Mixture Components And Interferents, Karthick Sothivelr, Florian Bender, Fabien Josse, Edwin E. Yaz, Antonio J. Ricco Aug 2018

Obtaining Chemical Selectivity From A Single, Nonselective Sensing Film: Two-Stage Adaptive Estimation Scheme With Multiparameter Measurement To Quantify Mixture Components And Interferents, Karthick Sothivelr, Florian Bender, Fabien Josse, Edwin E. Yaz, Antonio J. Ricco

Electrical and Computer Engineering Faculty Research and Publications

A new approach is reported to detect and quantify the members of a group of small-aromatic-molecule target analytes: benzene, toluene, ethylbenzene, and xylenes (BTEX), dissolved in water, in the presence of interferents, using only the data collected from a single polymer-coated SH-SAW (shear horizontal surface acoustic wave) device and a two-stage adaptive estimation scheme. This technique is composed of exponentially weighted recursive least-squares estimation (EW-RLSE) and a bank of Kalman filters (BKFs) and does not require any prior knowledge of the initial concentration range of the target analytes. The proposed approach utilizes the transient sensor response to sorption and/or desorption …


Stator Resistance Estimation Using Adaptive Estimation Via A Bank Of Kalman Filters, Alia R. Strandt, Andrew Strandt, Susan C. Schneider, Edwin E. Yaz Aug 2018

Stator Resistance Estimation Using Adaptive Estimation Via A Bank Of Kalman Filters, Alia R. Strandt, Andrew Strandt, Susan C. Schneider, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Accurate and efficient control of electric motors is dependent on knowledge of motor parameters such as the resistance and the inductance of the winding. However, these parameters are often unavailable to the control designer because they are dependent on the motor design and may change due to environmental effects such as temperature. An accurate real-time method to determine the values of these unknown parameters can improve motor performance over the entire operating range. In this work, a parameter estimation technique based on a bank of Kalman filters is used to adaptively estimate the motor winding resistance. Simulation results for a …


Coupled State-Dependent Riccati Equation Control For Continuous Time Nonlinear Mechatronics Systems, Xin Wang, Edwin E. Yaz, Susan C. Schneider Aug 2018

Coupled State-Dependent Riccati Equation Control For Continuous Time Nonlinear Mechatronics Systems, Xin Wang, Edwin E. Yaz, Susan C. Schneider

Electrical and Computer Engineering Faculty Research and Publications

This manuscript considers the coupled state-dependent Riccati equation approach for systematically designing nonlinear quadratic regulator and H control of mechatronics systems. The state-dependent feedback control solutions can be obtained by solving a pair of coupled state-dependent Riccati equations, guaranteeing nonlinear quadratic optimality with inherent stability property in combination with robust ℓ 2 type of disturbance reduction. The derivation of this control strategy is based on Nash's game theory. Both of finite and infinite horizon control problems are discussed. An underactuated robotic system, Furuta rotary pendulum, is used to examine the effectiveness and robustness of this novel nonlinear control approach.


Dissipative Resilient Observer, M. Sami Fadali, Edwin E. Yaz Aug 2018

Dissipative Resilient Observer, M. Sami Fadali, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Cybersecurity is a major concern for designers of control systems that can be directed against any of their components. Observers are an integral part of control systems that require state feedback. This paper considers an observer subject to errors in implementation or subject to cyberattacks. The errors and cyberattacks result in perturbations in the gain and in a finite-energy but unknown disturbance input. We obtain conditions for Q-S-R dissipativity and stability of the observer in the presence of the gain errors and disturbances in the form of linear matrix inequalities (LMIs). Three examples are presented to show how the LMIs …


Bio-Inspired Multi-Spectral Image Sensor And Augmented Reality Display For Near-Infrared Fluorescence Image-Guided Surgery, Nan Cui Aug 2018

Bio-Inspired Multi-Spectral Image Sensor And Augmented Reality Display For Near-Infrared Fluorescence Image-Guided Surgery, Nan Cui

McKelvey School of Engineering Graduate Student Theses & Dissertations

Background: Cancer remains a major public health problem worldwide and poses a huge economic burden. Near-infrared (NIR) fluorescence image-guided surgery (IGS) utilizes molecular markers and imaging instruments to identify and locate tumors during surgical resection. Unfortunately, current state-of-the-art NIR fluorescence imaging systems are bulky, costly, and lack both fluorescence sensitivity under surgical illumination and co-registration accuracy between multimodal images. Additionally, the monitor-based display units are disruptive to the surgical workflow and are suboptimal at indicating the 3-dimensional position of labeled tumors. These major obstacles have prevented the wide acceptance of NIR fluorescence imaging as the standard of care for cancer …


Multi-Gpu Acceleration Of Iterative X-Ray Ct Image Reconstruction, Ayan Mitra Aug 2018

Multi-Gpu Acceleration Of Iterative X-Ray Ct Image Reconstruction, Ayan Mitra

McKelvey School of Engineering Graduate Student Theses & Dissertations

X-ray computed tomography is a widely used medical imaging modality for screening and diagnosing diseases and for image-guided radiation therapy treatment planning. Statistical iterative reconstruction (SIR) algorithms have the potential to significantly reduce image artifacts by minimizing a cost function that models the physics and statistics of the data acquisition process in X-ray CT. SIR algorithms have superior performance compared to traditional analytical reconstructions for a wide range of applications including nonstandard geometries arising from irregular sampling, limited angular range, missing data, and low-dose CT. The main hurdle for the widespread adoption of SIR algorithms in multislice X-ray CT reconstruction …


Forward Electrophysiological Modeling And Inverse Problem For Uterine Contractions During Pregnancy, Mengxue Zhang Aug 2018

Forward Electrophysiological Modeling And Inverse Problem For Uterine Contractions During Pregnancy, Mengxue Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Uterine contractile dysfunction during pregnancy is a significant healthcare challenge that imposes heavy medical and financial burdens on both human beings and society. In the U.S., about 12% of babies are born prematurely each year, which is a leading cause of neonatal mortality and increases the possibility of having subsequent health problems. Post-term birth, in which a baby is born after 42 weeks of gestation, can cause risks for both the newborn and the mother. Currently, there is a limited understanding of how the uterus transitions from quiescence to excitation, which hampers our ability to detect labor and treat major …


Robust Engineering Of Dynamic Structures In Complex Networks, Walter Botongo Bomela Aug 2018

Robust Engineering Of Dynamic Structures In Complex Networks, Walter Botongo Bomela

McKelvey School of Engineering Graduate Student Theses & Dissertations

Populations of nearly identical dynamical systems are ubiquitous in natural and engineered systems, in which each unit plays a crucial role in determining the functioning of the ensemble. Robust and optimal control of such large collections of dynamical units remains a grand challenge, especially, when these units interact and form a complex network. Motivated by compelling practical problems in power systems, neural engineering and quantum control, where individual units often have to work in tandem to achieve a desired dynamic behavior, e.g., maintaining synchronization of generators in a power grid or conveying information in a neuronal network; in this dissertation, …


Self-Powered Time-Keeping And Time-Of-Occurrence Sensing, Liang Zhou Aug 2018

Self-Powered Time-Keeping And Time-Of-Occurrence Sensing, Liang Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

Self-powered and passive Internet-of-Things (IoT) devices (e.g. RFID tags, financial assets, wireless sensors and surface-mount devices) have been widely deployed in our everyday and industrial applications. While diverse functionalities have been implemented in passive systems, the lack of a reference clock limits the design space of such devices used for applications such as time-stamping sensing, recording and dynamic authentication. Self-powered time-keeping in passive systems has been challenging because they do not have access to continuous power sources. While energy transducers can harvest power from ambient environment, the intermittent power cannot support continuous operation for reference clocks. The thesis of this …


Statistical Performance Analysis Of Sparse Linear Arrays, Mianzhi Wang Aug 2018

Statistical Performance Analysis Of Sparse Linear Arrays, Mianzhi Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Direction-of-arrival (DOA) estimation remains an important topic in array signal processing. With uniform linear arrays (ULAs), traditional subspace-based methods can resolve only up to M-1 sources using M sensors. On the other hand, by exploiting their so-called difference coarray model, sparse linear arrays, such as co-prime and nested arrays, can resolve up to O(M^2) sources using only O(M) sensors. Various new sparse linear array geometries were proposed and many direction-finding algorithms were developed based on sparse linear arrays. However, the statistical performance of such arrays has not been analytically conducted. In this dissertation, we (i) study the asymptotic performance of …


Development Of Boron Calibration Via Hybrid Comparator Method In Prompt Gamma Activation Analysis, E. J. Artnak, S. R. Biegalski, S. Landsberger, Natale Lanno, Dennis Alexander, M. F. Byers Aug 2018

Development Of Boron Calibration Via Hybrid Comparator Method In Prompt Gamma Activation Analysis, E. J. Artnak, S. R. Biegalski, S. Landsberger, Natale Lanno, Dennis Alexander, M. F. Byers

Department of Electrical and Computer Engineering: Faculty Publications

The prompt gamma activation analysis (PGAA) facility at the Nuclear Engineering Teaching Laboratory at The University of Texas at Austin was utilized to quantify boron concentrations in boron carbide semiconductor films deposited on silicon substrates. Calibration was complicated by the unique and varying sample geometries analyzed. In addition, there was a dearth of solid materials available with quantified boron concentrations having comparable or readily modifiable dimensions to exploit for calibration purposes. Therefore, a novel hybrid comparator method was developed for the quantification of boron utilizing aluminum as an inexpensive and easily machinable reference material. Aluminum samples were manufactured with high …


Combined Use Of Oscillating Means And Ellipsometry To Determine Uncorrelated Effective Thickness And Optical Constants Of Material Deposited At Or Etched From A Working Electrode That Preferrably Comprises Non - Normal Oriented Nanofibers, Mathias M. Schubert, Tino Hofmann, John A. Woollam, Rebecca Y. Lai Aug 2018

Combined Use Of Oscillating Means And Ellipsometry To Determine Uncorrelated Effective Thickness And Optical Constants Of Material Deposited At Or Etched From A Working Electrode That Preferrably Comprises Non - Normal Oriented Nanofibers, Mathias M. Schubert, Tino Hofmann, John A. Woollam, Rebecca Y. Lai

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are systems and methods that enable determination of uncorrelated thickness of a working electrode and surface region optical constants in settings involving electrochemical processing at a working electrodes in a Piezo electric Balance system , by simultaneous application of an Ellipsometer system , the working electrode optionally having a multiplicity of nanofibers that are oriented non normally to a surface of said working electrode . Further disclosed is , simultaneous with said determinations , the monitoring of electrochemical processes at a piezoelectric balance working electrode driven by electrical energy applied between said working electrode and counter electrode .


Introducing The Boise State Bangla Handwriting Dataset And An Efficient Offline Recognizer Of Isolated Bangla Characters, Nishatul Majid, Elisa H. Barney Smith Aug 2018

Introducing The Boise State Bangla Handwriting Dataset And An Efficient Offline Recognizer Of Isolated Bangla Characters, Nishatul Majid, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

This introduces the Boise State Bangla Handwriting Dataset, a publicly accessible offline handwriting dataset of Bangla script. This can be found at https://scholarworks.boisestate.edu/saipl/1/

A basic character recognition method is presented where the features are extracted based on zonal pixel counts, structural strokes and grid points with U-SURF descriptors modeled with bag of features.

Benchmarking with this approach on 3 other publicly available Bangla datasets is reported. The highest classification accuracy obtained with an SVM classifier based on a cubic kernel is 96.8%.


Indirect Imaging Using Heterodyne Remote Digital Holography, Muralidhar Madabhushi Balaji Aug 2018

Indirect Imaging Using Heterodyne Remote Digital Holography, Muralidhar Madabhushi Balaji

Electrical Engineering Theses and Dissertations

Conventional line-of-sight imaging techniques rely on detecting light paths bouncing from the object and reaching directly to the detector. Absence of any such direct light paths from object to detector results in a failure to recover any useful information using conventional techniques. The absence of direct light paths from object to detector can be observed in several real-world scenarios such as looking around a corner, imaging through turbid media, imaging through tissue etc.

The focus of this thesis is pertaining to the problem of looking around corners (or) imaging object hidden from line of sight at macroscopic scales. This thesis …


Quadrotor Swarm Arena (Quasar) Development Of A Swarm Control Testbed, Shane T. Stebler, William Mackunis Aug 2018

Quadrotor Swarm Arena (Quasar) Development Of A Swarm Control Testbed, Shane T. Stebler, William Mackunis

Beyond: Undergraduate Research Journal

Swarm control systems are increasingly popular in the robotics industry and academia due to their many potential applications. The goal of the Quadrotor Swarm Arena (QuaSAr) project is to construct a quadrotor swarm control testbed to provide researchers with the tools needed to experimentally investigate this emerging science. This testbed is equipped with a motion capture system, test control station, and numerous quadrotor UAVs. MATLAB-Simulink is utilized for control law development, data processing, and test control. This configuration allows researchers to test developing control law in a 'plug and play' manner as control development and test control are all completed …


Forensic Analysis Of Immersive Virtual Reality Social Applications: A Primary Account, Ananya Yarramreddy, Peter Gromkowski, Ibrahim Baggili Aug 2018

Forensic Analysis Of Immersive Virtual Reality Social Applications: A Primary Account, Ananya Yarramreddy, Peter Gromkowski, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Our work presents the primary account for exploring the forensics of immersive Virtual Reality (VR) systems and their social applications. The Social VR applications studied in this work include Bigscreen, Altspace VR, Rec Room and Facebook Spaces. We explored the two most widely adopted consumer VR systems: the HTC Vive and the Oculus Rift. Our tests examined the efficacy of reconstructing evidence from network traffic as well as the systems themselves. The results showed that a significant amount of forensically relevant data such as user names, user profile pictures, events, and system details may be recovered. We anticipate that this …


Improved Iterative Truncated Arithmetic Mean Filter, Prathyusha Surampudi Venkata Aug 2018

Improved Iterative Truncated Arithmetic Mean Filter, Prathyusha Surampudi Venkata

LSU New Orleans Theses and Dissertations

This thesis discusses image processing and filtering techniques with emphasis on Mean filter, Median filter, and different versions of the Iterative Truncated Arithmetic Mean (ITM) filter. Specifically, we review in detail the ITM algorithms (ITM1 and ITM2) proposed by Xudong Jiang. Although filtering is capable of reducing noise in an image, it usually also results in smoothening or some other form of distortion of image edges and file details. Therefore, maintaining a proper trade off between noise reduction and edge/detail distortion is key. In this thesis, an improvement over Xudong Jiang’s ITM filters, namely ITM3, has been proposed and tested …


Node-Based Resilience Measure Clustering With Applications To Noisy And Overlapping Communities In Complex Networks, John Matta, Tayo Obafemi-Ajayi, Jeffrey Borwey, Koushik Sinha, Donald C. Wunsch, Gunes Ercal Aug 2018

Node-Based Resilience Measure Clustering With Applications To Noisy And Overlapping Communities In Complex Networks, John Matta, Tayo Obafemi-Ajayi, Jeffrey Borwey, Koushik Sinha, Donald C. Wunsch, Gunes Ercal

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines a schema for graph-theoretic clustering using node-based resilience measures. Node-based resilience measures optimize an objective based on a critical set of nodes whose removal causes some severity of disconnection in the network. Beyond presenting a general framework for the usage of node-based resilience measures for variations of clustering problems, we experimentally validate the usefulness of such methods in accomplishing the following: (i) clustering a graph in one step without knowing the number of clusters a priori; (ii) removing noise from noisy data; and (iii) detecting overlapping communities. We demonstrate that this clustering schema can be applied successfully …


Relationship Between Time-Constants And 3db Cutoff Of High-Order Damped Lti Systems, Vladimir I. Prodanov, Katherina Prodanov Aug 2018

Relationship Between Time-Constants And 3db Cutoff Of High-Order Damped Lti Systems, Vladimir I. Prodanov, Katherina Prodanov

Electrical Engineering

This paper deals with linear time-invariant (LTI) systems and examines the link between the 3dB cutoff and time-constants. It shows that the cutoff frequency of a low-pass damped network can be estimated from the reciprocal of a p-norm calculated from the system's time-constants. Furthermore, to achieve good accuracy the p factor must have a fractional value, for example, p=1.7. Two formulas are derived, and their performance evaluated using Monte Carlo simulations which reveal a sub-3% error for most cases.


Prior Day Effect In Forecasting Daily Natural Gas Flow From Monthly Data, Maral Fakoor, George F. Corliss, Ronald H. Brown Aug 2018

Prior Day Effect In Forecasting Daily Natural Gas Flow From Monthly Data, Maral Fakoor, George F. Corliss, Ronald H. Brown

Electrical and Computer Engineering Faculty Research and Publications

Many needs exist in the energy industry where measurement is monthly yet daily values are required. The process of disaggregation of low frequency measurement to higher frequency values has been presented in this literature. Also, a novel method that accounts for prior-day weather impacts in the disaggregation process is presented, even though prior-day impacts are not directly recoverable from monthly data. Having initial daily weather and gas flow data, the weather and flow data are aggregated to generate simulated monthly weather and consumption data. Linear regression models can be powerful tools for parametrization of monthly/daily consumption models and will enable …


Internet Traffic Forecasting Model Using Self Organizing Map And Support Vector Regression Method, Enrico Laoh, Fakhrul Agustriwan, Chyntia Megawati, Isti Surjandari Aug 2018

Internet Traffic Forecasting Model Using Self Organizing Map And Support Vector Regression Method, Enrico Laoh, Fakhrul Agustriwan, Chyntia Megawati, Isti Surjandari

Makara Journal of Technology

Internet traffic forecasting is one of important aspect in order to fulfill the customer demand. So, the service quality of internet service provider (ISP) can be maintained at the good level. In this study self-organizing map (SOM) and support vector regression (SVR) algorithm are used as forecasting method. SOM is first used to decompose the whole historical data of traffic internet into clusters, while SVR is used to build a forecasting model in each cluster. This method is used to forecast ISPs traffic internet in Jakarta and surrounding areas. The result of this study shows that SOM-SVR method gives more …


Effects Of The Preheating Temperature On The Crystal Structure And Texture Of Martensitic Stainless Steel, Tri Hardi Priyanto, Rifai Muslih, Herry Mugirahardjo, Bharoto Bharoto, Andon Insani, Muzzakiy Muzzakiy Aug 2018

Effects Of The Preheating Temperature On The Crystal Structure And Texture Of Martensitic Stainless Steel, Tri Hardi Priyanto, Rifai Muslih, Herry Mugirahardjo, Bharoto Bharoto, Andon Insani, Muzzakiy Muzzakiy

Makara Journal of Technology

Theoretically, the preheating temperature refers to the start martensite temperature (Ms), and the martensite transformation can be considered as the conservation of the invariant habit-plane in the lattice structure. The habit-plane is the interface plane between austenite and martensite as measured on a macroscopic scale. From the calculation, Ms = 252 °C. The martensite formation can be affected by temperature or stress treatment. In this experiment, temperature treatment was conducted. The sample was treated at 250 °C ± 10 °C. Before and after the pre-heat treatment, the sample was characterized using the neutron diffraction method. BATAN’s Texture Diffractometer (DN2) with …


Investigation Of Ship Hull Girder Strength With Grounding Damage, Muhammad Zubair Muis Alie, Ristiyanto Adiputra Aug 2018

Investigation Of Ship Hull Girder Strength With Grounding Damage, Muhammad Zubair Muis Alie, Ristiyanto Adiputra

Makara Journal of Technology

The objective of the present study is to investigate ship hull girder strength as a result of grounding damage upon longitudinal bending. A bulk carrier and tanker are analyzed and Smith’s Method is adopted and implemented in the analysis program. An efficient solution procedure is performed by assuming the cross-section remains plane and the vertical bending moment is applied to the cross section. As a fundamental case, the damage is simply created by removing the elements from the cross section. Welding residual stress, initial imperfections, and crack extensions are not considered. The grounding damage is made by two conditions, namely …