Engineering Commons^™

Describing Landscape Structure Improvement According To Experimental Results, Fu-Ming Chang, Ning-Chien Tung

Journal of Marine Science and Technology–Taiwan

This study investigated silt movement and the influence of fine sand on downstream ecology during movement by using a small indoor physical model for simulating onsite conditions. The obtained data were analyzed to determine the impact of silt on ecological habitats and can serve as a reference for future onsite and ecology investigations. Before a dam was removed to allow a downstream riverway to restore the initial environment, the riverway stabilized at approximately 960 s, and the dam was removed at approximately 1140 s. After the dam was removed, the silt in each channel section evidently increased, and after a …

Composite Coastal Protection Methods Used At Cijin Coast, Taiwan, Hong-Mo Wu, Shao-Gu Kuo, Yen-Ting Lai, Li-An Kuo, Chia-Yan Cheng, Jyh-Cheng Chu, Yang-Yih Chen, John R. C. Hsu

Journal of Marine Science and Technology–Taiwan

Cijin Coast has suffered from severe beach erosion and a consequent coastline retreat. To analyze the trend of topographic evolution of Cijin Coast, bathymetric data from field investigation were used and both numerical simulation and physical modeling were implemented in the wave basin to obtain the corresponding parameters that replicate similar phenomena. To protect Cijin Coast, composite coastal protection methods, such as submerged detached breakwaters accompanied with artificial nourishments, were proposed. Parameters used in previous studies were employed to test the proposed protection methods, and the results showed that the methods were effective in preventing the consequent retreat of the …

Improving Detection Technique For Flight Recorders Of The Distress Airplanes Crashed Into Ocean By Integrating Inertial Navigation System Into Underwater Locator Beacon, Sheng-Shih Wang, Hsien-Sen Hung, Jyh-Jier Ho, Jie-Xian Lin, Chi-Hsiao Yeh

Journal of Marine Science and Technology–Taiwan

Flight recorder, used to analyze distress reasons, is equipped with underwater locator beacon (ULB) for being detected and recovered easily in sea. According to the recovery report for the Air France flight no. AF447 distress airplane, it nearly took two years and cost 40 million US dollars to search and recover the flight recorders. Apparently, future aviation safety could be greatly improved if earlier recovery of the flight recorders would reveal the crash reasons sooner. Therefore, this paper is aimed to develop an enhanced ULB, which integrates inexpensive inertial navigation system (INS) into ULB, for a cost-effective and time-saving operation …

Effects Of Generator Parameters And Transformer Disposal On Dynamics Of A High-Penetration No-Storage Wind-Diesel System, Chi-Hsiang Lin

Journal of Marine Science and Technology–Taiwan

In this paper, dynamics of a high-penetration, no-storage wind-diesel (HPNSWD) system subjected to line faults are studied. It is found that the effect of induction generator electrical parameters on generator electromagnetic torque, system frequency and generator terminal voltage is significant, especially for the rotor resistance, which is able to significantly affect all the three target performances. Therefore, it will be the most effective way to improve the system dynamics by controlling the rotor resistance. It is also found that the system dynamics would be significantly improved by disposing a distribution transformer. However, the effectiveness depends on the installation position. A …

Coupling Vof/Plic And Embedding Method For Simulating Wave Breaking On A Sloping Beach, Tai-Wen Hsu, Chih-Min Hsieh, Chin-Yen Tsai, Shan-Hwei Ou

Journal of Marine Science and Technology–Taiwan

A 2-D numerical model was developed to simulate wave breaking on a sloping beach. The model solves the Reynolds Averaged Navier-Stokes (RANS) equations coupled with the k-ε turbulence closure model. To track free surface configurations, the volume of fluid with piecewise linear interface calculation (VOF/PLIC) is employed. An embedding method (EB) is also used to treat complex bottom topography. Coupling these two methods for simulating wave breaking on a sloping beach, good agreement between numerical results and laboratory observations is found for spilling breaker. Wave breaking characteristics is in terms of free surface profiles, mean velocities and wave heights based …

Elastohydrodynamic Lubrication Of Circular Contacts At Pure Squeeze Motion Involving The Mixture Of Two Lubricants, Li-Ming Chu, Yuh-Ping Chang, Jer-Jia Sheu

Journal of Marine Science and Technology–Taiwan

This study investigated the pure squeeze elastohydrodynamic lubrication (EHL) motion of circular contacts by using mixed rheology fluid models under constant load conditions. The lubricant was a homogeneous mixture of a Newtonian base oil and couple stress fluid at various volume fractions. The simulation results revealed that the effect of the couple stress fluid was equivalent to enhancing the viscosity of the lubricant. Therefore, the central film thickness and minimum film thickness increased with the volume fraction of the couple stress fluid (ν). The central pressure decreased as ν increased. In addition, the normal squeeze velocity followed the ensuing order: …

The New Method To Evaluate The Uplift Capacity Of Belled Piles In Sandy Soil, Jaw-Guei Lin, Shih-Yu Hsu, San-Shyan Lin

Journal of Marine Science and Technology–Taiwan

In conventional geotechnical engineering, the pull out of pile is always blamed only on the shear failure of the soil caused by the uplift force developed from the tip of the pile. For the belled pile, however, the enlarged foundation plays an important role to against the compression/uplift load, and the current theories for estimating the uplift capacities of the pile were found more than 50% relative error from measured. In this study, a new method for estimating the ultimate uplift capacity of the belled pile embedded in sandy soil was developed by taking into account the elastic/plastic behavior of …

The Kriging Cloud Computing Framework: Interpolation Of Topography By Cloud Computing With The Kriging Algorithm, Cheng-Tsan Lai, Sung-Shan Hsiao, Hui-Ming Fang, Edward H. Wang

Journal of Marine Science and Technology–Taiwan

Spatial information surveyed by photogrammetry, airborne LiDAR and Mobile Measurement System (MMS) above ground level can be analyzed by scientists using standard geostatistical methodologies such as ordinary Kriging and sequential Gaussian simulation to interpolate heterogeneities of profiles from sparse sample data. Proven effective by researchers, the Kriging algorithm model is used by commercial data analysis packages for instant interpolation. However, meaningful and reliable results only come with a comprehensive understanding of the variogram associated with valid mathematical functions. To capture spatial landscape variations from massive sample grids of satellite images, this paper presents a cloud computing-based automation approach to improve …

Effects Of Battery Energy Storage System On The Operating Schedule Of A Renewable Energy Based Tou Rate Industrial User Under Competitive Environment, Chun-Lung Chen, Yu-Liang Lin, Wen-Yu Fu

Journal of Marine Science and Technology–Taiwan

With increasing development of smart grid and restructuring of the power industry, the problem of operating schedule for a time-of-use (TOU) rate industrial customer may become a more important issue due to the inclusion of the variations in the TOU rate structures. This paper develops a new algorithm, named intelligent particle swarm optimization (INPSO), to solve the operating schedule of a renewable energy based TOU rate industrial user with battery energy storage system (BESS). Adding another particle best (Pbestap) item with a diversity based judgment mechanism, proposed INPSO algorithm can give a good direction to enhance its search capacity that …

Unraveling The Formation Of Continental Crust : A Review And Outlook, Eason Hong, Wei-Ting Kao

Journal of Marine Science and Technology–Taiwan

The early Earth is generally believed to be a hot planet with a primitive basaltic oceanic crust. However, the question of how a batholiths-bearing continent was formed is still unresolved. Although many hypothetical interpretations seem appealing, the origin and volume dilemma of the batholiths is still under debate. According to recent literature, the Hadean Ocean is characterized by heat, acidity and reduction, significantly unlike its counterparts in Earth's history. We have found that this crucial marine setting, favoring the chemical weathering of basaltic rocks, is the key element for forming and stabilizing the primitive continents through convergent tectonics and the …

Book Review: High G Flight - Physiological Effects And Countermeasures, Stefan Kleinke

International Journal of Aviation, Aeronautics, and Aerospace

This review provides insight on the content and a review of the quality of the recent release of High G Flight - Physiological Effects and Countermeasures from Ashgate Publications.

This review does not reflect the views of IJAAA or ERAU. This work was not peer reviewed.

High G Flight - Physiological Effects and Countermeasures

Aviation Bird Hazard In Nexrad Dual Polarization Weather Radar Confirmed By Visual Observations, Bradley M. Muller, Frederick R. Mosher, Christopher G. Herbster, Anthony T. Brickhouse

International Journal of Aviation, Aeronautics, and Aerospace

Birds represent a significant hazard to flying aircraft as illustrated by the “Miracle on the Hudson” encounter in 2009 between U.S. Airways Flight 1549 and a flock of Canada Geese, forcing the flight to ditch in the river. Birds are common in the skies over Florida during the spring migration season, and often appear in the National Weather Service’s (NWS) NEXRAD weather radar imagery as an easily recognizable signature known as a “roost ring.” This paper presents a NEXRAD roost ring case in central Florida in a rare instance where the signatures were confirmed by visual observations of the birds. …

Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D.,

International Journal of Aviation, Aeronautics, and Aerospace

Both, a global isothermal temperature model and a nonlinear quadratic temperature model of the ISA was developed and presented here. Constrained optimization techniques in conjunction with the least-square-root approximations were used to design best-fit isothermal models for ISA pressure and density changes up to 47 geopotential km for NLPAM, and 86 orthometric km for ISOAM respectively. The mass of the dry atmosphere and the relevant fractional-mass scale heights have been computed utilizing the very accurate eight-point Gauss-Legendre numerical quadrature for both ISOAM and NLPAM. Both, the ISOAM and the NLPAM represent viable alternatives to ISA in many practical applications and …

Application Of Fiscal Incentives For Development Of East Natuna Gas Field For Long-Term National Natural Gas Demand, Marwan Batubara, Widodo Wahyu Purwanto, Akhmad Fauzi

Makara Journal of Technology

East Natuna gas field, which has proven reserves of 46 trillion cubic feet, is projected to meet long-term natural gas needs. However, CO2-content of the gas reserves reaches 71%, leading to expensive development costs. This research investigates the feasibility of the field based on several fiscal incentives. Firstly, gas supply-demand until year 2040 was analyzed. Then, based on the analysis, the field was developed using high CO2 gas separation technology to produce gas of 1300 MMSCFD in 2023, 2600 MMSCFD in 2031, and 3900 MMSCFD in 2039. Finally, the economic feasibility was assessed using cash flow analysis in accordance with …

Thermodynamic Analysis Of Irreversible Heat-Transformers, Niccolo` Giannetti, Arnas Arnas, Andrea Rocchetti, Kiyoshi Saito

Makara Journal of Technology

Absorption heat transformers extend the possibilities for efficient and environment-friendly energy conversion processes. Based on a general thermodynamic model of three-thermal cycles with finite thermal capacity of the heat sources, this paper is intent upon analyzing and optimizing the performance of absorption heat transformers, by including the influence of irreversibility in the analytical expression of the system efficiency. Dimensionless parameters for an overall optimization are defined and a first screening is performed to clarify their influence. Dependence on the main factors is highlighted to suggest how to change them in order to enhance the whole system performance. Under this point …

A New Method For Simulating Power Flow Density Focused By A Silicon Lens Antenna Irradiated With Linearly Polarized Thz Wave, Catur Apriono, Eko Tjipto Rahardjo, Norihisa Hiromoto

Makara Journal of Technology

A terahertz system uses dielectric lens antennas for focusing and collimating beams of terahertz wave radiation. Linearly polarized terahertz wave radiation has been widely applied in the terahertz system. Therefore, an accurate method for analyzing the power flow density in the dielectric lens antenna irradiated with the linearly polarized terahertz wave radiation is important to design the terahertz systems. In optics, ray-tracing method has been used to calculate the power flow density by a number density of rays. In this study, we propose a method of ray-tracing combined with Fresnel’s transmission, including transmittance and polarization of the terahertz wave radiation …

High Temperature Corrosion Of Aluminized Aisi 4130 Steel With The Different Composition Of Nacl/Na2so4 Deposits, Mohammad Badaruddin, Chaur Jeng Wang, Yudhistyra Saputra, Abu Khalid Rivai

Makara Journal of Technology

The high temperature corrosion of AISI 4130 steel can be increased by hot-dip aluminizing coating. The aluminized steel specimens with the deposit composition of 100/0, 30/70, 50/50, 70/30, and 0/100 (wt.%) NaCl/Na2SO4 were oxidized at 750 °C for 1-49 h periods. According to a parabolic rate constant (kp) value, the aluminized steel with deposit composition of 70/30 NaCl/Na2SO4 shows the highest kp value (3.71 × 10-11 g2cm- 4s-1), later followed by the kp value of 3.35 × 10-11 g2cm-4s-1 for 100/0 and the lowest kp value is 7.731 × 10-12 g2cm-4s-1 for 0/100. Whereas, the kp value for the aluminized …

Effects Of Supplier-Manufacturer Relationships On Supply-Chain Performance Of Manufacturing Industries In Indonesia, Rachmad Hidayat, Khisbullah Hudha, Sabarudin Akhmad

Makara Journal of Technology

The present study describes the relationships between commitment, communication, satisfaction, trust, relationship quality with suppliers, and supply-chain performance. The population of the study was manufacturing companies in Indonesia. Respondents were the chief executive officers or corporate secretaries or the designated managers involved in strategic decision making. Samples were taken by using a proportional area random sampling technique. Structural Equation Modeling (SEM) was used for analysis. Results of both direct and indirect testing of hypothesis indicated two hypotheses of positive and significant effects and nine hypotheses of positive but insignificant effects. Those hypotheses of positive and significant effects were the direct …

Stochastic Optimization Of Supply Chain Risk Measures –A Methodology For Improving Supply Security Of Subsidized Fuel Oil In Indonesia, Adinda Yuanita, Andi Noorsaman Sommeng, Anondho Wijonarko

Makara Journal of Technology

Monte Carlo simulation-based methods for stochastic optimization of risk measures is required to solve complex problems in supply security of subsidized fuel oil in Indonesia. In order to overcome constraints in distribution of subsidized fuel in Indonesia, which has the fourth largest population in the world—more than 250,000,000 people with 66.5% of productive population, and has more than 17,000 islands with its population centered around the nation's capital only—it is necessary to have a measurable and integrated risk analysis with monitoring system for the purpose of supply security of subsidized fuel. In consideration of this complex issue, uncertainty and probability …

Transmission Electron Microscopy Characterization Of High-Temperatur Oxidation Of Fe-20cr-5al Alloy Prepared By Focused Ion Beam Technique, Mohammad Dani, Pudji Untoro, Teguh Yulius Surya Panca Putra, Parikin Parikin, Joachim Mayer, Arbi Dimyati

Makara Journal of Technology

The Focused Ion Beam (FIB) technique was applied for cross section preparation of the oxidized alloy for Transmission Electron Microscopy (TEM) study. Prior to preparation, the specimens of Fe-20Cr-5Al alloy sheet were oxidized in air at 1200 oC for 2 minutes, 10 minutes, 2 hours, and 100 hours. The microstructure and elemental composition of the samples were characterized using TEM equipped with an Energy Dispersive X-Ray Spectroscopy (EDX). The Electron Energy Loss Spectroscopy (EELS) was used to determine of the light elements. The TEM investigation reveals remarkable microstructure evolution of the specimens during oxidation which generally exhibit a typical multi-layer …

Examining How Breakdowns In Pilot Monitoring Of The Aircraft Flight Path, Robert Sumwalt, David Cross, Dennis Lessard

International Journal of Aviation, Aeronautics, and Aerospace

Aircraft accident and incident data reveal that serious safety consequences can arise when flight crewmembers fail to properly monitor the aircraft flight path. This research study reviewed human factors literature to better understand why pilots fail to properly monitor, and analyzed accident and incident data. Recommendations for improving monitoring performance were formulated, which may be useful to air carriers in implementing a new Federal Aviation Administration requirement that calls for specific training in monitoring.

Comparison Of Accuracies In Techniques For Evaluating Wind Power Density, Reuben Kainkwa, John Kumwenda

Tanzania Journal of Science

Wind power is among important renewable sources of energy. In order to know the magnitude of wind power, appropriate techniques for evaluating it need to be investigated. Apart from the standard formula that can be used to evaluate wind power density at a site there are two more techniques namely power law exponent and Weibull two-parameter density function. However the accuracy of the latter two methods relative to the standard one has not yet been investigated. The main objective of this paper is to compare accuracies of these techniques. The wind power densities were calculated using standard formula, Weibull model …

Effects Of Target Composition On The Optical Constants Of Dc Sputtered Zno:Al Thin Films, B. Samwel, M. E. Samiji, N.R. Mlyuka

Tanzania Journal of Science

Al-doped ZnO thin films were deposited from ZnO:Al ceramic and Zn:Al metal alloy targets in Ar and Ar + O2 atmospheres respectively, using Direct Current (DC) magnetron sputtering. The samples exhibited transmittance T > 80% in visible region with good NIR shielding.  The results indicated that, band gap energy ranged from 3.34 to 3.44 eV and 3.39 to 3.46 eV for films prepared from alloy and ceramic targets, respectively. Films obtained from alloy target at a substrate temperature of 200 oC showed low electrical sheet resistance of 10 Ω/sq, and highest values of mobility (15.9 cm2/Vs) and carrier concentration (2.98 × …

Novelty Wins, “Straight Toward Objective” Loses! Or Book Review: Why Greatness Cannot Be Planned: The Myth Of The Objective, By Kenneth O. Stanley And Joel Lehman, Reuben Hersh

Journal of Humanistic Mathematics

Experiments in evolutionary artificial intelligence demonstrate that progress toward an important, difficult goal is not best achieved by attempting to go directly toward that goal, but rather, by rewarding novelty.

57th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 57th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Snowbird, Utah, July 26-31, 2015.

Shooting For The Sky: Martin Tengler Is Part Of A Team That Wants To Use Drones To Plant A Billion Trees A Year, Gerry Boyle

Colby Magazine

Martin Tengler '12 can picture a time when aerial drones fan out to map vast reaches of deforested land and then plant thousands of seed pods that will turn wasteland into new forest.

Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall

International Journal of Nuclear Security

The ability to determine the age of seized nuclear material—that is, the time that has passed since it was formed— would provide crucial data to be used in its investigation. This paper reviews the methods and mathematical reasoning behind the use of diffusion theory, as previously applied to analysis of metals in ancient artifacts and other objects, to modern investigations in nuclear science. We here examine the time-dependent processes of diffusion, including grain boundary diffusion and discontinuous precipitation, and we assess the utility of examining the profiles of impurity and alloying element concentrations for use as a tool in pre-detonation …

Student Writing Competition

International Journal of Nuclear Security

No abstract provided.

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International Journal of Nuclear Security

No abstract provided.

Masthead

International Journal of Nuclear Security

No abstract provided.