Engineering Commons^™

Simple: System Automatic Essay Assessment For Indonesian Language Subject Examination, Anak Agung Putri Ratna, Bagio Budiardjo, Djoko Hartanto

Makara Journal of Technology

SIMPLE: System Automatic Essay Assessment for Indonesian Language Subject Examination. Evaluation of study of a student is a very important aspect of an educational process. Evaluation is aimed at measuring the level of student understanding of the given lecture materials. Measuring student understanding of the course material, using essay-type exam, is generally used as the evaluation tool. In this essay-type exam, the student has to answer questions using sentences, whereby choices of possible answers are not indicated. The student has to answer the questions with his/her sentences. The answers may vary, since it reflects the student’s best thoughts of the …

Utilization Of Bagasse Cellulose For Ethanol Production Through Simultaneous Saccharification And Fermentation By Xylanase, M. Samsuri, Misri Gozan, R. Mardias, M. Baiquni, Heri Hermansyah, Anondho Wijanarko, Bambang Prasetya, M. Nasikin

Makara Journal of Technology

Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase. Bagasse is a solid residue from sugar cane process, which is not many use it for some product which have more added value. Bagasse, which is a lignosellulosic material, be able to be use for alternative energy resources like bioethanol or biogas. With renewable energy resources a crisis of energy in Republic of Indonesia could be solved, especially in oil and gas. This research has done the conversion of bagasse to bioethanol with xylanase enzyme. The result show that bagasse contains of 52,7% cellulose, 20% hemicelluloses, …

Construction Of Short-Length High-Rates Ldpc Codes Using Difference Families, Deny Hamdani, Ery Safrianti

Makara Journal of Technology

Low-density parity-check (LDPC) code is linear-block error-correcting code defined by sparse parity-check matrix. It is decoded using the massage-passing algorithm, and in many cases, capable of outperforming turbo code. This paper presents a class of low-density parity-check (LDPC) codes showing good performance with low encoding complexity. The code is constructed using difference families from combinatorial design. The resulting code, which is designed to have short code length and high code rate, can be encoded with low complexity due to its quasi-cyclic structure, and performs well when it is iteratively decoded with the sum-product algorithm. These properties of LDPC code are …

Kinetic Model For Triglyceride Hydrolysis Using Lipase:Review, Heri Hermansyah, A. Wijanarko, Dianursanti Dianursanti, Misri Gozan, Praswasti P. D.K Wulan, Rita Arbianti, Roekmijati W. Soemantojo, Tania Surya Utami, Yuliusman Yuliusman, Momoji Kubo, Naomi Shibasaki Kitakawa, Toshiy Yonemoto

Makara Journal of Technology

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction …

Sulfonation Of Cptfe Film Grafted Styrene For Proton Exchange Membrane Fuel Cell, Yohan Yohan

Makara Journal of Technology

Sulfonation of cPTFE Film grafted Styrene for Proton Exchange Membrane Fuel Cell. Sulfonation of γ-ray iradiated and styrene-grafted crosslinked polytetrafluoroethylene film (cPTFE-g-S film) have been done. The aim of the research is to make hydropyl membrane as proton exchange membrane fuel cell. Sulfonation was prepared with chlorosulfonic acid in chloroethane under various conditions. The impact of the percent of grafting, the concentration of chlorosulfonic acid, the reaction time,and the reaction temperature on the properties of sulfonated film is examinated. The results show that sulfonation of surface-grafted films is incomplete at room temperature. The increasing of concentration of chlorosulfonic acid and …

A Bimodular Polyconvex Anisotropic Strain Energy Function For Articular Cartilage, Stephen M. Klisch

Mechanical Engineering

A strain energy function for finite deformations is developed that has the capability to describe the nonlinear, anisotropic, and asymmetric mechanical response that is typical of articular cartilage. In particular, the bimodular feature is employed by including strain energy terms that are only mechanically active when the corresponding fiber directions are in tension. Furthermore, the strain energy function is a polyconvex function of the deformation gradient tensor so that it meets material stability criteria. A novel feature of the model is the use of bimodular and polyconvex “strong interaction terms” for the strain invariants of orthotropic materials. Several regression analyses …

Agile Mpc System Linking Manufacturing And Market Strategies, Ahmed M. Deif, Waguih H. Elmaraghy

Industrial Technology and Packaging

Increasing complexity and interdependency in manufacturing enterprises require an agile manufacturing paradigm. This paper considers a dynamic control approach for linking manufacturing strategy with market strategy through a reconfigurable manufacturing planning and control (MPC) system to support agility in this context. A comprehensive MPC model capable of adopting different MPC strategies through distributed controllers of inventory, capacity, and WIP is presented. A hierarchical supervisory controller (referred to as decision logic unit, DLU) that intakes the high-level strategic market decisions and constraints together with feedback of the current manufacturing system state (WIP, production, and inventory levels) and optimally manages the distributed …

Maximizing Communication Concurrency Via Link-Layer Packet Salvaging In Mobile Ad Hoc Networks, Chansu Yu, Kang G. Shin, Lubo Song

Electrical and Computer Engineering Faculty Publications

Carrier-sense medium access control (MAC) protocols such as the IEEE 802.11 distributed coordination function (DCF) avoid collisions by holding up pending packet transmission requests when a carrier signal is observed above a certain threshold. However, this often results in unnecessarily conservative communication, thus making it difficult to maximize the utilization of the spatial spectral resource. This paper shows that a higher aggregate throughput can be achieved by allowing more concurrent communications and adjusting the communication distance on the fly, which needs provisions for the following two areas. On the one hand, carrier sense-based MAC protocols do not allow aggressive communication …

Regulating Waste Discharge With Fuzzy Effluent Limitations For Toxic Pollutants, Tong Yin, David King Stevens

Civil and Environmental Engineering Faculty Publications

Many traditional water quality standards are based on extreme percentiles; often, there is the risk of making wrong decisions with these standards because of high estimation uncertainty. Standards expressed as fuzzy intervals in the form of [trigger, enforcement limitation] make it possible to control the risks for the discharger and the consumer simul taneously. With fuzzy interval compliance, corrective action is initiated when the trigger is exceeded; noncompliance is declared when the en forcement limitation is exceeded. Fuzzy intervals would digest the risks that are inherent when a single enforcement limitation is used to determine compliance; the risks can be …

Social Network Structures In Open Source Software Development Teams, Y. Long, Keng Siau

Research Collection School Of Computing and Information Systems

Drawing on social network theories and previous studies, this research examines the dynamics of social network structures in open source software (OSS) teams. Three projects were selected from SourceForge.net in terms of their similarities as well as their differences. Monthly data were extracted from the bug tracking systems in order to achieve a longitudinal view of the interaction pattern of each project. Social network analysis was used to generate the indices of social structure. The finding suggests that the interaction pattern of OSS projects evolves from a single hub at the beginning to a corel periphery model as the projects …

Simulations Of Intracellular Calcium Release Dynamics In Response To A High-Intensity, Ultrashort Electric Pulse, R. P. Joshi, A. Nguyen, V. Sridhara, Q. Hu, R. Nuccitelli, Stephen J. Beebe, J. Kolb, Karl H. Schoenbach

Bioelectrics Publications

Numerical simulations for electrically induced, intracellular calcium release from the endoplasmic reticulum are reported. A two-step model is used for self-consistency. Distributed electrical circuit representation coupled with the Smoluchowski equation yields the ER membrane nanoporation for calcium outflow based on a numerical simulation. This is combined with the continuum Li-Rinzel model and drift diffusion for calcium dynamics. Our results are shown to be in agreement with reported calcium release data. A modest increase (rough doubling) of the cellular calcium is predicted in the absence of extra-cellular calcium. In particular, the applied field of 15 kV/cm with 60 ns pulse duration …

Effects Of Ocean Thermocline Variability On Noncoherent Underwater Acoustic Communications, Martin Siderius, Michael B. Porter, Paul Hursky, Vincent Mcdonald

Electrical and Computer Engineering Faculty Publications and Presentations

The performance of acoustic modems in the ocean is strongly affected by the oceanenvironment. A storm can drive up the ambient noise levels, eliminate a thermocline by wind mixing, and whip up violent waves and thereby break up the acoustic mirror formed by theocean surface. The combined effects of these and other processes on modem performance are not well understood. The authors have been conducting experiments to study these environmental effects on various modulation schemes. Here the focus is on the role of the thermocline on a widely used modulation scheme (frequency-shift keying). Using data from a recent experiment conducted …

Spontaneous Mode Locking In Mixed-Broadened Laser Oscillators, Pitak Chenkosol, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

A theoretical model is reported for spontaneous mode locking in mixed-broadened laser oscillators. Experimental observations of this effect have been available for many years, but no rigorous interpretation has been given. Numerical calculations emphasize the case of a high-gain xenon laser, for which extensive experimental data have been published. Complex pulsation characteristics are observed as the cavity length and pumping rate are varied, and the theoretical results are in good agreement with the experimental data.

Potentiality Of Biogas And The Role Of Substrates In Biogas Formation Potential, Scott Shealy

Independent Study Project (ISP) Collection

Biogas infrastructure development, particularly in countries such as Vietnam, has the potential to provide great benefits to people living agrarian lifestyles in rural areas. Decentralized wastewater treatment facilities that utilize anaerobic technologies to digest organic waste for the purpose of collecting methane provide a number of benefits to centralized use as well. In both cases, users benefit from the production of methane gas, wastewater treatment, nutrient recycling, and organic fertilizers. In the case of decentralized use, as is most prevalent in Vietnam, integrated farming methods, such as the VACB model, allow farmers to reap the benefits of a wide array …

Predicting The Impacts Of Serra Leste: A Case Study In Companhia Vale Do Rio Doce’S Influence On Southern Pará, Jason Hayes

Independent Study Project (ISP) Collection

This project analyzes the possible environmental and socioeconomic impacts of Serra Leste, a newly proposed iron mine by the Companhia Vale do Rio Doce (CVRD). However, Serra Leste is also part of a much larger system of CVRD projects which has recently had a profound influence on the micro-region surrounding Curionópolis, the future cite of the operation. Interviews, CVRD studies, and secondary sources were used and contrasted to evaluate the situation from several angles. Environmentally, Serra Leste will have profound impacts on the water, air, and soil. Specifically, the mine will probably have the largest influence on regional water tables, …

Micro Synthetic Jets As Effective Actuator, Mehti Koklu

Mechanical & Aerospace Engineering Theses & Dissertations

Synthetic jets have previously been studied as actuators for external macroflow control and recently been proposed for internal microflow applications. Despite the wide variety of the potential applications of synthetic jet actuators, the majority of the studies have been done at macro scales. Furthermore, there has not been any design methodology that addresses the effectiveness of the micro synthetic jet actuators. Bearing these needs in mind, a micro synthetic jet configuration is considered in a microscale environment where Kn number is less than 0.1 and more than 0.001. Flowfields are simulated by solving the compressible Navier-Stokes equations. The wall boundary …

A Resolution Enhancement Technique In Digital Images, Mehmet R. Ormanoglu

Electrical & Computer Engineering Theses & Dissertations

Image enhancement is the processing of images to increase their usefulness. The image enhancement methods and objectives vary with the application. When images are enhanced for human viewers, as in television, the objective is mostly to improve perceptual aspects: image quality, intelligibility, or visual appearance. The aim of this research work is to make the processed image better in the visual sense than the unprocessed image. An image can often be enhanced by modifying its contrast or dynamic range, increasing the sharpness of edges, reducing the noise, or reducing the blurring. The most commonly used contrast enhancement technique is histogram …

Derivation And Application Of A Conserved Orbital Energy For The Inverted Pendulum Bipedal Walking Model, Jerry E. Pratt, Sergey V. Drakunov

Publications

We present an analysis of a point mass, point foot, planar inverted pendulum model for bipedal walking. Using this model, we derive expressions for a conserved quantity, the “Orbital Energy”, given a smooth Center of Mass trajectory. Given a closed form Center of Mass Trajectory, the equation for the Orbital Energy is a closed form expression except for an integral term, which we show to be the first moment of area under the Center of Mass path. Hence, given a Center of Mass trajectory, it is straightforward and computationally simple to compute phase portraits for the system. In fact, for …

Band Gap Engineering Of Two Dimensional Silicon Photonic Crystals By Oxidation And Oxide Etching, Makhin Thitsa

Electrical & Computer Engineering Theses & Dissertations

In this thesis a thorough analysis is presented on the effects of oxidation and oxide etching on the band structure of two dimensional silicon photonic crystals (2 D Si PC's). By using the plane wave expansion method (PWM), two structures of triangular lattice, namely, air cylinders embedded in a silicon background and silicon cylinders embedded in an air background are modeled. The thesis focuses on triangular lattice arrangement because for certain parameter values such a lattice can give rise to absolute band gap, which prohibits the propagation of either transverse electric (TE) or transverse magnetic (TM) polarizations.

During oxidation three …

Numerical Study Of Flow In Three-Dimensional Fiber Networks And Sedimentation Of Curved Fiber By Lattice Boltzmann Method, Xiaoying Rong

Dissertations

Fiber network is modeled as a three-dimensional random cylindrical fiber network. Nonlinear behavior of fluid flowing through the fiber network is numerically simulated by using the lattice Boltzmann (LB) method. Nonlinear relationship between the friction factor and the modified Reynolds number is simulated and analyzed by using the Fochheimer equation, which includes the quadratic term of velocity. There is a transition from linear to nonlinear region when the Reynolds numbers are sufficiently high, reflecting the inertial effect of the flows. The simulated permeability of such fiber network is compared to the experimental results and the finite element simulations.

Dynamic motions …

Steganalysis Feature Improvement Using Expectation Maximization, Benjamin M. Rodriguez, Gilbert L. Peterson, Sos S. Agaian

Faculty Publications

No abstract provided.

Uncertainty Assessment In High-Risk Environments Using Probability, Evidence Theory And Expert Judgment Elicitation, Stella Barberis Bondi

Engineering Management & Systems Engineering Theses & Dissertations

The level of uncertainty in advanced system design is assessed by comparing the results of expert judgment elicitation to probability and evidence theory. This research shows how one type of monotone measure, namely Dempster-Shafer Theory of Evidence can expand the framework of uncertainty to provide decision makers a more robust solution space. The issues imbedded in this research are focused on how the relevant predictive uncertainty produced by similar action is measured.

This methodology uses the established approach from traditional probability theory and Dempster-Shafer evidence theory to combine two classes of uncertainty, aleatory and epistemic. Probability theory provides the mathematical …

A Risk- And Fuzzy Set-Based Methodology For Advanced Concept Technology Demonstration Military Utility Assessment Design, Thomas James Meyers

Engineering Management & Systems Engineering Theses & Dissertations

The U.S. Department of Defense Advanced Concept Technology Demonstration (ACTD) and derivative, rapid acquisition programs offer timely solutions to critical military needs by assessing the utility of technologies mature enough to be fielded without application of traditional, defense system development processes. Military utility assessments (MUA) are ACTDs' most critical features, but the lack of a standard for identifying assessment criteria tailored to specific demonstrations risks poorly informed acquisition decisions and the military operations those decisions are intended to support.

The purpose of this research was to develop and deploy a methodology for identifying measures of effectiveness integral to advanced concept …

The Distributed Independent-Platform Event-Driven Simulation Engine Library (Diesel), Reejo Mathew

Electrical & Computer Engineering Theses & Dissertations

The Distributed, Independent-Platform, Event-Driven Simulation Engine Library (DIESEL) is a simulation executive, capable of supporting both sequential and distributed discrete-event simulations. A system level specification is provided along with the expected behavior of each component within DIESEL. This behavioral specification of each component, along with the interconnection and interaction between the different components, provides a complete description of the DIESEL behavioral model. The model provides a considerable amount of freedom for an application developer to partition the simulation model, when building sequential and distributed applications with respect to balancing the number of events generated across different components. It also allows …

Detecting Compromised Nodes In Wireless Sensor Networks, Mary Lisa Mathews

Electrical & Computer Engineering Theses & Dissertations

While wireless sensor networks are proving to be a versatile tool, many of the applications in which they are utilized have sensitive data. Therefore, security is crucial in many of these applications. Once a sensor node has been compromised, the security of the network degrades quickly if measures are not taken to deal with this event. There have been many approaches researched to tackle the issue. In this thesis, an anomaly-based intrusion detection protocol is developed to detect compromised nodes in wireless sensor networks.

The proposed protocol is implemented after the sensors are deployed into the environment in which they …

Molecular Dynamics Simulations To Probe Effects Of Ultra-Short, Very-High Voltage Pulses On Cells, Viswanadham Sridhara

Electrical & Computer Engineering Theses & Dissertations

The use of very high electric fields (∼ 100kV/cm or higher) with pulse durations in the nanosecond range (Ultra-short) has been a very recent development in bioelectrics. Traditionally, the electric field effects have mostly been confined to: (a) low field, long-duration pulses, and (b) focused mainly on electroporation studies. Thus, aspects such as possible field-induced DNA damage, calcium release, alterations in neuro-transmitters, or voltage-gating have generally been overlooked.

Ultra-short, high-field pulses open the way to targeted and deliberate apoptotic cell killing (e.g., of tumor cells). Though experimental data is very useful, it usually yields information on macroscopic variables that is …

Production Of Hydrogen And Sulfur From Hydrogen Sulfide In A Nonthermal-Plasma Pulsed Corona Discharge Reactor, Morris D. Argyle, Gui-Bing Zhao, Sanil John, Ji-Jun Zhang, Jerry C. Hamann, Suresh S. Muknahallipatna, Stanislaw Legowski, John F. Ackerman

Faculty Publications

Hydrogen Sulfide (H2S) dissociation into hydrogen and sulfur has been studied in a pulsed corona discharge reactor (PCDR). Due to the high dielectric strength of pure H2S (~2.9 times higher than air), a non-thermal plasma could not be sustained in pure H2S at discharge voltages up to 30kV with our reactor geometry. Therefore, H2S was diluted with another gas with lower dielectric strength to reduce the breakdown voltage. Breakdown voltages of H2S in four balance gases (Ar, He, N2 and H2) have been measured at different H2S concentrations and pressures. Breakdown voltages are proportional to the partial pressure of H2S …

Adsorption Of Lead (Ii) Ions By Organosilicate Nanoporous Materials, Larry Keith Isaacs

Civil & Environmental Engineering Theses & Dissertations

As-synthesized organosilicate nanoporous (OSNP) materials HMS (hexagonal mesoporous structure) and MCM-41 were used as adsorbents for removal of lead (II) ions in laboratory batch and column studies. Mesoporous organosilicates were prepared from tetraethylorthosilicate (TEOS) and either an ionic (cetyltrimethyl-ammonium) or neutral (dodecylamine) surfactant. Batch reaction distribution coefficients for MCM-41 were K_D = 51.5 L/g (SD = 26.3) at 24 h and K_D = 73.7 L/g (SD = 40.5) at 7 d. OSNP lead (II) ion adsorption increased from pH = 3 until pH ca. 7.5 after which a sharp decrease in adsorption was noted. OSNP materials reflected a …

Reach Adaptation And Final Position Control Amid Environmental Uncertainty After Stroke, Robert A. Scheidt, Tina M. Stoeckmann

Biomedical Engineering Faculty Research and Publications

We characterized how hemiparetic stroke survivors and neurologically intact individuals adapt reaching movements to compensate for unpredictable environmental perturbations. We tested the hypotheses that like unimpaired subjects, hemiparetic stroke survivors adapt using sensory information obtained during only the most recent movements and that the reliability of target acquisition decreases as the degree of sensorimotor impairment increases. Subjects held the handle of a two-joint robotic arm that applied forces to the hand while reaching between targets in a horizontal plane. The robot simulated a dynamic environment that varied randomly in strength from one trial to the next. The trial sequence of …

A Wavelet Based Complementary Approach For Image Enhancement, Ismail Kosum

Electrical & Computer Engineering Theses & Dissertations

Detail in an image means more meaningful information that is very important in many computer vision and pattern recognition applications. The object region visibility in an image plays an important role in obtaining accurate and desired information from the original image. In particular, image processing techniques developed for region segmentation and object classification have better results depending on the visibility in images. There are several enhancement techniques available which are capable of obtaining clear images with balanced lighting and contrast. In this thesis, a completely image dependent approach to enhance the luminance of images under extreme lighting conditions and a …