Civil Engineering Commons^™

Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis

Makara Journal of Technology

The needs of smaller size RF varactor is a must today, and MEMS comes to be the potential one. In this paper we proposed an adjustable resonance RF-MEMS varactor by using comb-drive actuators placing in each side of the square movable plate. In our preliminary simulation, we found that the device can work properly but some constraints comes such as the dominancies of harmonic resonance frequencies that influences into the nominal capacitances. Therefore for the next step of development we have to find out the window of the structural dimension for a certain spans and a certain operating frequencies.

Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari

Makara Journal of Technology

In a manufacturing company, manufacturing costs, or component prices, and tolerance will affect the price and the quality of a product. Companies must produce high-quality products with low manufacturing costs in order to keep their products competitive in the market; however, it is difficult to produce a high-quality product with a low manufacturing cost. Companies have difficulties in determining the components to be produced using their own manufacturing facilities (make) or outsourced to their suppliers (buy). Hence, a make or buy analysis is needed to minimize the manufacturing costs and quality loss and to determine the optimum alternative regarding make …

Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe

Makara Journal of Technology

As electronic device dimensions are continuously reduced, applied bias conditions significantly change and the transport mechanisms must be reconsidered. Tunneling devices are promising for scaled-down electronics because of expected high-speed operation and relatively low bias. In this work, we investigated the tunneling features in silicon-oninsulator lateral nanowire pn junction and pin junction devices. By controlling the substrate voltage, tunneling features can be observed in the electrical characteristics. We found that the minimum substrate voltage required for tunneling to occur in pn junctions is higher as compared with pin junctions. The main cause of these effects relies in the difference between …

Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto

Makara Journal of Technology

We studied the effect of Argon (Ar) ion irradiation on Fe-Al2O3 nanogranular thin film. X-ray diffraction (XRD) patterns show that the ion dose might promote the growth of the Fe2O3 phase from an amorphous phase to a crystalline phase. The magnetic and magnetoresistance properties were investigated using a vibrating sample magnetometer (VSM) and a four point probe (FPP). The results suggest that percolation concentration occurred at the 0.55 Fe volume fraction and with a maximum magnetoresistance (MR) ratio of 3%. The present MR ratio was lower than that of previous results, which might be related to the existence of the …

Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya

Makara Journal of Technology

This research evaluated the effect of fungal pretreatment of betung bamboo fibers and enzymatic- and microwaveassisted hydrolysis on the reducing sugar yield. The enzymatic hydrolysis of the pretreated biomass was carried out with cellulase and 10 and 20 FPU/g of substrate in a shaking incubator at 50 °C and 150 rpm for 48 h. The sulfuric acid concentration used in the microwave-assisted acid hydrolysis was 1.0, 2.5, and 5%, either with or without the addition of activated carbon. Microwave irradiation (330 Watt) was applied for 5–12.5 min. The yield of reducing sugar was better with the microwave-assisted acid hydrolysis, and …

Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao

Makara Journal of Technology

We have developed a multi-gated field emitter (FE) such as a quadruple-gated FE with a three-stacked electrode lens and a quintuple-gated FE with a four-stacked electrode lens. Both the FEs can focus the electron beam. However, the quintuple-gated FE has a stronger electron convergence than the quadruple-gated FE, and a beam crossover is clearly observed for the quintuple-gated FE.

Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani

Makara Journal of Technology

Lignin from lignocellulosic biomass is a potential biopolymer for wood adhesive. The aims of this study were to characterize lignin isolated from the black liquor of oil palm empty fruit bunch fiber pretreated with steam explosion in alkaline conditions and to examine the bond quality of aqueous polymer isocyanate (API) adhesive prepared from lignin, natural rubber latex (NRL), and polyvinyl alcohol (PVA) as base polymers with isocyanate crosslinkers. Lignin was precipitated from the black liquor by adding hydrochloric acid; then the precipitate was separated by filtration, thoroughly washed with water up to pH 2 and pH 5, and dried. The …

The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa

Makara Journal of Technology

Dimensionality reduction based on appearance has been interesting issue on the face image research fields. Eigenface and Fisherface are linear techniques based on full spectral features, for both Eigenface and Fisherface produce global manifold structure. Inability of them in yielding local manifold structure have been solved by Laplacianfaces and further improved by Orthogonal Laplacianfaces, so it can yield orthogonal feature vectors. However, they have also a weakness, when training set samples have non-linear distribution. To overcome this weakness, feature extraction through data mapping from input to feature space using Gaussian kernel function is proposed. To avoid singularity, the Eigenface decomposition …

Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto

Makara Journal of Technology

The aim of this research is to study dye-sensitized solar cells (DSSC). This was implemented on a flexible polyethylene terephthalate (PET) substrate using a mixture of transparent and scattered mesoporous anatase-titania as the electron transport layer for the photoelectrode. This mixture of anatase titania performed a dual function of light scattering and efficient dye absorption. In this study, a porous nano-TiO2 film was prepared on indium tin oxide (ITO) coated polyethylene terephthalate (PET) by using a binder-free titania paste; on it, a DSSC was fabricated. The paste which contained a mixture of TiO2 nanoparticles, acid chloride, and ethanol was printed …

Dynamic Testing Of An Elevated Water Tank, Alexander Michael Font

Graduate Theses and Dissertations

The objective of this thesis was to identify the modal properties of a pedesphere type, elevated water tank under different operating conditions relating to the water level in the tank. The research that was conducted included both numerical and experimental components. The numerical components consisted of a simple hand calculation to identify the fundamental frequency as well as numerical computer models to identify the natural frequencies and mode shapes for the first three bending modes. The experimental components consisted of characterizing the vibration of the elevated water tank in its current environment through ambient vibration testing.

Multiple Reference Impact Testing Of Bridges Using A Network Of Low-Cost Dynamic Exciters, James David Lindsey

Graduate Theses and Dissertations

Multiple Reference Impact Testing (MRIT) is a form of Experimental Modal Analysis (EMA) that can be used to identify the dynamic properties of full-scale bridges. These dynamic properties include natural frequencies, mode shapes, damping ratios, modal scaling and modal flexibility. Since these system properties that are directly related to the mass and stiffness characteristics of a structure, impact test measurements can be used to quantitatively characterize condition of a structure. Over time, changes in the properties can be monitored and evaluated as indicators of damage or deterioration. Instrumented hammers and drop masses are typically used to perform MRIT by providing …

Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe

Graduate Theses and Dissertations

A compacted clay liner (test pad) was constructed and instrumented with volumetric water content and soil matric potential sensors to determine soil water characteristic curves (SWCC) and hydraulic conductivity (k) functions. Specifically, the compacted clay liner was subjected to an infiltration cycle during a sealed double ring infiltrometer (SDRI) test followed by a drying cycle. After the drying cycle, Shelby tube samples were collected from the compacted clay liner and flexible wall permeability (FWP) tests were conducted on sub-samples to determine the saturated hydraulic conductivity. Moreover, two computer programs (RETC and UNSAT-H) were utilized to model the SWCCs and k-functions …

Modot Pavement Preservation Research Program, David Newton Richardson, Neil Lennart Anderson, John Bowders, Andrew Z. Boeckmann, Ronaldo Luna, S. Michael Lusher, Brent Rosenblad, Lesley Sneed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The following report documents a research project on pavement preservation performed by the Missouri University of Science and Technology (Missouri S&T) and the University of Missouri-Columbia (UMC) on behalf of the Missouri Department of Transportation (MoDOT). the report consists of a Summary Report followed by six detailed technical reports. to achieve the goal of reducing maintenance costs and improving minor road ratings, MoDOT has embarked upon a plan of formalizing its maintenance/preservation planning. to assist in developing the plan, MoDOT contracted with the Missouri S&T and UMC to conduct a research project, entitled "MoDOT Pavement Preservation Research Program". the product …

Assessment Of Nitrifying Bacteria In Massard Plant Using Molecular Tools, Jennifer Puanani Holmes-Smith

Civil Engineering Undergraduate Honors Theses

The discharge of nutrients (such as nitrogen and phosphorus) from wastewater treatment plants (WWTP) has become an increasingly important issue in the United States. Ammonia (NH3) is a common contaminant found in domestic wastewater and agricultural runoff. It can cause toxicity in fish if left untreated. The United States Environmental Protection Agency (EPA) recommends low national criteria for ammonia limits in freshwater. With these greater restrictions, ammonia-nitrogen limit compliance (5 mg/L) has become an issue at the Massard WWTP in Fort Smith, Arkansas. The purpose of this research is to assess the ammonia removal in the Massard WWTP in order …

Decentralized Water Systems For Sustainable And Reliable Supply, Suraj Goverdhanam

All Theses

The water industry is under enormous pressure to provide potable water in circumstances of increasing demands due to population growth, lifestyle change of people and depleting freshwater resources. Deteriorating infrastructure makes the task of meeting the human water consumption needs even more challenging. Distributed water supply systems are currently pursued as a sustainable alternative in arid regions of US to exploit the potential of water reclamation at community or district level to reduce the dependence on freshwater resources. An extension of such a distributed water supply alternative is a complete decentralized supply, which requires on-site water reclamation. The intention of …

Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.

Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station …

Anammox Polishing In Mainstream Wastewater Treatment To Meet Stringent Ammonia And Total Nitrogen Limits, Rebecca Mary Holgate

Civil & Environmental Engineering Theses & Dissertations

As nitrogen discharge limits are becoming more stringent there is a need for new processes that are sustainable and cost effective. Since anaerobic ammonia oxidizing bacteria (anammox) were discovered in the mid 1990s, there has been considerable success implementing anammox in many wastewater treatment plants to treat internally generated nitrogen rich waste streams (e.g. centrate). Recently, there has also been discussion of implementing anammox in mainstream wastewater treatment to exploit the benefits of autotrophic nitrogen removal.

A two stage A/B pilot study was conducted that included a high-rate activated sludge (HRAS) process followed by a two-stage de-ammonification process incorporating nitrite-shunt …

Evaluating The Impact Of Bridge Deck Removal Method On The Performance Of Precast/Prestressed Concrete I-Girders, Shaddi Assad

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Wide flange precast/prestressed concrete I-girders have been widely used by several State Departments of Transportation (DOTs) in the last two decades. These girders have many advantages over standard AASHTO I-girders. Their wide and thick bottom flange accommodates a large number of prestressing strands and their wide and thin top flange provides a shorter deck span, reduced girder weight, greater stability in construction, and adequate platform for workers. Despite these advantages, the wide and thin top flange might be disadvantageous when it comes to deck removal, as it is more susceptible to damage. Therefore there is a need to investigate the …

Learning From Earthquakes: 2014 Napa Valley Earthquake Reconnaissance Report, Erica Fischer

Lyles School of Civil Engineering Graduate Student Reports

Structural damage was observed during reconnaissance after the 2014 South Napa Earthquake, and included damage to wine storage and fermentation tanks, collapse of wine storage barrel racks, unreinforced masonry building partial or full collapse, and residential building damage. This type of damage is not unique to the South Napa Earthquake, and was observed after other earthquakes such as the 1977 San Juan Earthquake, and the 2010 Maule Earthquake. Previous research and earthquakes have demonstrated the seismic performance of cylindrical fluid-filled tanks is controlled by both the tank and the sloshing motion of the liquid inside. Unlike building structures, steel tanks …

Optimal Design Of Validation Experiments For Calibration And Validation Of Complex Numerical Models, Matthew Egeberg

All Theses

As prediction of the performance and behavior of complex engineering systems shifts from a primarily empirical-based approach to the use of complex physics-based numerical models, the role of experimentation is evolving to calibrate, validate, and quantify uncertainty of the numerical models. Oftentimes, these experiments are expensive, placing importance on selecting experimental settings to efficiently calibrate the numerical model with a limited number of experiments. The aim of this thesis is to reduce the experimental resources required to reach predictive maturity in complex numerical models by (i) aiding experimenters in determining the optimal settings for experiments, and (ii) aiding the model …

Dual-State Kalman Filter Forecasting And Control Theory Applications For Proactive Ramp Metering, Brian Richard Portugais

Boise State University Theses and Dissertations

Deterioration of freeway traffic flow condition due to bottlenecks can be ameliorated with ramp metering. A challenge in ramp metering is that it is not possible to process data in real-time and use the output in a control algorithm. This is due to the fact that by the time processing is completed and a control measure applied, the traffic state will have changed. A solution to this problem is to forecast the traffic state and implement a control measure based on the forecast.

A dual-state Kalman filter was used to forecast traffic data at two locations on a freeway (I-84). …

Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

This study examines connections between mean sea level (MSL) variability and diurnal and semidiurnal tidal constituent variations at 17 open-ocean and 9 continental shelf tide gauges in the western tropical Pacific Ocean, a region showing anomalous rise in MSL over the last 20 years and strong interannual variability. Detrended MSL fluctuations are correlated with detrended tidal amplitude and phase fluctuations, defined as tidal anomaly trends (TATs), to quantify the response of tidal properties to MSL variation. About 20 significant amplitude and phase TATs are found for each of the two strongest tidal constituents, K₁ (diurnal) and M₂ (semidiurnal). …

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a …

Transport Properties Of Nano-Silica Contained Self-Consolidating Concrete, Borhan Moradi

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this research study, transport properties of various self-consolidating concretes (SCCs) containing nano-particles (SiO2) were investigated. Nano-silica replaced a portion of the cementitious materials at different replacement levels ranging from 1.5 to 7.5% by weight. For the purpose of this investigation, flow, bulk, and transport properties of SCCs were studied. The investigated transport properties were absorption, water penetration, rapid chloride permeability, capillary absorption, rapid migration, and chloride diffusion. Transport properties of nano-silica SCCs were also compared to those of equivalent silica fume (micro silica) contained concretes, as well as those of control mixture (concrete without nano or micro silica).

Test …

Evaluation Of Earthquake Hazard For Las Vegas Valley, Nevada Incorporating Probabilistic Hazard Assessment And Non--Linear Site Response, Suchan Lamichhane

UNLV Theses, Dissertations, Professional Papers, and Capstones

Abstract from Manuscript 1, "An alternative analysis of the probabilistic seismic hazard for Las Vegas Valley, Nevada": Probabilistic seismic hazard calculations relevant for rock-site conditions in the Las Vegas Valley, Nevada (LVV) have been computed that account for seismic sources that are not included in the current (2008) USGS national seismic hazard model (NSHM) because of insufficient knowledge or documentation, using the commercial software package EZ-FRISK. The LVV is underlain by a system of mapped, active normal faults that comprise the Las Vegas Valley Fault System (LVVFS), with maximum potential earthquakes to M6.8. The 2008 NSHM explicitly includes only one …

Application Of Bamboo For Flexural And Shear Reinforcement In Concrete Beams, Nathan Schneider

All Theses

As the developing world is industrializing and people migrate to cities, the need for infrastructure is growing quickly and concrete has become one of the most widely used construction materials. One poor construction practice observed widely across the developing world is the minimal use of reinforcement for concrete structures due to the high cost of steel. As a low-cost, high-performance material with good mechanical properties, bamboo has been investigated as an alternative to steel for reinforcing concrete. The goal of this research is to add to the knowledge base of bamboo reinforced concrete (BRC) by investigating a unique stirrup design …

Building Envelope Failure Assessment Of Residential Developments Subjected To Hurricane Wind Hazards, James Grayson

All Dissertations

An unfortunate global precedent has been set by hurricane wind hazard events that illustrate the importance of building resilient coastal communities. Although community resilience is heavily dependent upon the socioeconomic response of the community before, during, and after a hazard event, it is also dependent on the vulnerability of the community to a disaster. Therefore, one way that structural engineers can assist communities in becoming more resilient is to investigate and implement methods that mitigate the 'initial shock' experienced by a residential development subjected to a hazard event. The focus of this research was to develop a mechanics-based building envelope …

Projections Of Future Us Design Wind Speeds Due To Climate Change For Estimating Hurricane Losses, Fangqian Liu

All Dissertations

Hurricane is among the most dangerous and costliest natural hazards that affect the coastal environment of the United States (U.S.) every year. Hurricane activities have been observed to change in many aspects since the last century including the changes in both intensity and annual storm frequency. The extent to which aspect of climate change contributes to the variation in hurricane activities from long-term historical statistics is still not clearly understood at this point. This study examines the impacts of two climate change effects (change in annual storm frequency and sea surface temperature) on future U.S. design wind speeds for the …

Fluid Mud Gravity Currents Through Emergent Aquatic Vegetation, Nazli Yilmaz

All Dissertations

In this theoretical and experimental investigation, the propagation dynamics of the fluid-mud underflows form in pipeline dredge disposal operations in the designated areas are studied. These areas such as wetlands, nearshore waters are typically covered with stiff, cylindrical, emergent aquatic vegetation. The main goals of this study are to propose mathematical formulations for the bottom shear force and drag force of emergent stiff aquatic vegetation acting on the gravity current, and to present novel propagation modeling approaches. To be able to predict these forces, a friction coefficient (for the bottom shear force), and a drag coefficient (for vegetation skin friction …

Increased Span Length For The Mgs Long-Span Guardrail System, Nicholas A. Weiland

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Long-span guardrail systems have been recognized as an effective means of shielding low-fill culverts while minimizing construction efforts and limiting culvert damage and repair. The current MGS long-span design provided the capability to span unsupported lengths up to 25 ft (7.6 m) without the use of nested guardrail. The excellent performance of the MGS long-span system in full-scale crash tests suggested that longer span lengths may be possible with the current design.

A detailed analysis of the MGS long-span guardrail system was performed using the finite element software program LS-DYNA^®. It was shown that the MGS long-span design …