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Articles 23251 - 23280 of 27385

Full-Text Articles in Engineering

Vector Quantization Based On Steady-State Memetic Algorithm, Chien-Min Ou Aug 2010

Vector Quantization Based On Steady-State Memetic Algorithm, Chien-Min Ou

Journal of Marine Science and Technology–Taiwan

A novel memetic algorithm (MA) for the design of vector quantizers (VQs) is presented in this paper. The algorithm uses steady-state genetic algorithm (GA) for the global search and K-means algorithm for the local improvement. As compared with the usual MA using the generational GA for global search, the proposed MA dramatically reduces the computational time for VQ training. In addition, it attains a near global optimal solution, and its performance is insensitive to the selection of initial codewords. Numerical results show that it can save more than 70% of computation time while maintaining a comparable performance as previous MA

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Experimental Study On The Influence Of Geometrical Configuration Of Porous Floating Breakwater On Performance, Huan-Yu Wang, Zhao-Chen Sun Aug 2010

Experimental Study On The Influence Of Geometrical Configuration Of Porous Floating Breakwater On Performance, Huan-Yu Wang, Zhao-Chen Sun

Journal of Marine Science and Technology–Taiwan

The general aims of this paper were to present a novel floating breakwater fabricated with large numbers of diamondshaped blocks and find out the favorable characteristics of geometrical configurations basing on wave attenuation and mooring force debasement. The research are expected to offer a little of information for the design of floating breakwater. Four sorts (with equal number of blocks) of geometrical configurations had been involved in the contrasting analyses. Various factors including water depth, relative width of the floating body and wave steepness were considered. The results had shown that the proposed porous floating breakwater revealed favorable performance and …

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52nd Rocky Mountain Conference On Analytical Chemistry Aug 2010

52nd Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 52nd annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Snowmass, Colorado, August 1-5, 2010.

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Effect Of K2o/Sio2 Ratio On The Crystallization Of Leucite In Silicate-Based Glasses, P Sooksaen, J Boonmee, C Witpathomwong, S Likhitlert Jul 2010

Effect Of K2o/Sio2 Ratio On The Crystallization Of Leucite In Silicate-Based Glasses, P Sooksaen, J Boonmee, C Witpathomwong, S Likhitlert

Journal of Metals, Materials and Minerals

Leucite-based glass-ceramics were prepared by controlled crystallization of suitable glass compositions to give required crystalline phase/s. Three glass batches in the system SiO2 - K2O - NaO2 - Al2O3 - TiO2 - CaO were prepared by varying K2O/SiO2 ratio, then melted and quenched. Glasses were characterized for onset of crystallization temperatures by differential thermal analysis (DTA), and heat treatments were carried out from 850 - 1000°C for 4 hours for controlled crystallization of leucite phase. Physical, chemical and crystal structure characterizations were carried out using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). XRD found …

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Effect Of Chitosan's Molecular Weights On Mangosteen Dye Fixation On Cotton Fabric, C Suitcharit, F Awae, W Sengmama, K Srikulkit Jul 2010

Effect Of Chitosan's Molecular Weights On Mangosteen Dye Fixation On Cotton Fabric, C Suitcharit, F Awae, W Sengmama, K Srikulkit

Journal of Metals, Materials and Minerals

The effect of chitosan's molecular weights (Mw) on mangosteen dye fixation on cotton was studied using chitosans with Mw of 226 kDa (CTS-Mw I; native chitosan), 10.8 kDa (CTS-Mw II), and 7.2 kDa (CTS-Mw III). The preparation of chitosan with different Mws was carried out using sodium nitrite in acid media (depolymerization process). The obtained chitosans were applied onto cotton fabric. The effect of chitosan concentrations on fixation and fastness properties of mangosteen dye extract was studied. The results showed that an increase in concentrations of depolymerized chitosans (CTS-Mw II and III) yielded an increase in N% contents. Nonetheless, the …

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Bs News July/August Jul 2010

Bs News July/August

Building Services Engineering

No abstract provided.

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Utilization Of Fly Ash From Power Plant For Adsorption Of Hydrocarbon Contamination In Water, J Sasithorn, D Wiwattanadate, S Sangsuk Jul 2010

Utilization Of Fly Ash From Power Plant For Adsorption Of Hydrocarbon Contamination In Water, J Sasithorn, D Wiwattanadate, S Sangsuk

Journal of Metals, Materials and Minerals

Adsorption efficiency of polycyclic aromatic hydrocarbons (PAHs) contamination in water with rice husk fly ash from a power plant was investigated in comparison with coal fly ash and silica from rice husk fly ash, with and without surface treatment. Naphthalene was used as a representative for PAHs, and Cethyltrimethylammoniumbromide (CTAB) was used as surface treating agent for the present study. Various factors, such as shaking rate, shaking time, pH of naphthalene aqueous solution, and adsorbentnaphthalene weight ratio, were investigated to identify the optimum condition for each adsorbent. Upon using 0.3 g adsorbent in 100 ml of 10 mg/l naphthalene solution, …

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An Investigation Of Microstructural Change Of Low Alloy Steel Aisi 4150 By Seebeck Coefficient, T Samran, P Termsuksawad Jul 2010

An Investigation Of Microstructural Change Of Low Alloy Steel Aisi 4150 By Seebeck Coefficient, T Samran, P Termsuksawad

Journal of Metals, Materials and Minerals

Low alloyed steels, whose hardness can be modified by heat treatment, have been widely used in various applications. After heat treatment, they are normally destructively characterized and tested by many approaches via optical microscope and hardness testing. It is useful to develop a non-destructive method relating to its properties and microstructures. The proposed non-destructive approach in this study is the Seebeck coefficient measurement. The materials in this study were carbon steels AISI 4150 rod with a diameter of 1.3 cm and length of 3 cm. The specimens were heat-treated at 900ºC for 1 hour and were then cooled to room …

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Adhesion Behavior In Sliding Test Of Austenitic Stainless Steel On Vc Coated By Trd Process, R Piewnim, P Sricharoenchai Jul 2010

Adhesion Behavior In Sliding Test Of Austenitic Stainless Steel On Vc Coated By Trd Process, R Piewnim, P Sricharoenchai

Journal of Metals, Materials and Minerals

Austenitic stainless steel is prone to adhere to tool steels which are used as forming tools. This causes difficulties in the formation of stainless steels.(1) Hard coating on forming tools is a method to diminish adhesion problems. In this work, adhesive behavior of stainless steel was tested against VC coated by thermo-reactive deposition and diffusion (TRD) process. Sliding wear test was conducted under unlubricated condition at room temperature by a ring-on-disc tester. AISI 304 was used as a ring for sliding couple with VC coating layer. DC 53 steel was used as a disc on which VC with a thickness …

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Pickling Kinetics Of Tertiary Oxide Scale Formed On Hot-Rolled Steel Strip, Y Jatuphaksamphan, N Phinichka, K Prapakorn, M Supradist Jul 2010

Pickling Kinetics Of Tertiary Oxide Scale Formed On Hot-Rolled Steel Strip, Y Jatuphaksamphan, N Phinichka, K Prapakorn, M Supradist

Journal of Metals, Materials and Minerals

During hot rolling process a steel strip covers with oxide scales. These scales have to be removed by acid pickling process. This work focuses on the study of the scale removing rate of a hot-rolled steel strip in order to find an expression explaining the rate of reaction in hydrochloric acid. The study of scale removal is accomplished by utilizing the pickling simulator with different acid concentrations and pickling temperatures. There are two approaches that can be used to find a scale removing rate; the measurement of weight change and the iron concentration change after the pickling process. In this …

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Preparation Of Hydrophobic Chitosan Using Complexation Method For Pla/Chitosan Blend, P Chouwatat, P Polsana, P Noknoi, K Siralertmukul, K Srikulkit Jul 2010

Preparation Of Hydrophobic Chitosan Using Complexation Method For Pla/Chitosan Blend, P Chouwatat, P Polsana, P Noknoi, K Siralertmukul, K Srikulkit

Journal of Metals, Materials and Minerals

In this study, dioctyl sulfosuccinate-chitosan complex was prepared by a mechanical mixing of aqueous chitosan with sodium dioctyl sulfosuccinate. As a result, hydrophobic chitosan was achieved. Characterizations of the complex were carried out including XRD, TGA, and FT-IR in order to follow changes in the chitosan structure. Thus produced chitosan complex was hydrophobic and anticipated to be compatible with PLA. Solution blending of PLA and hydrophobic chitosan was then conducted. Characterization techniques including XRD and FT-IR were employed to investigate the structure of the polymer blend. FTIR spectra showed that changes in the fingerprint of the chitosan amide band in …

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Thermal Analysis Of Fe-Carbide And Fe-C Mixtures, R Tongsri, B Vetayanugul Jul 2010

Thermal Analysis Of Fe-Carbide And Fe-C Mixtures, R Tongsri, B Vetayanugul

Journal of Metals, Materials and Minerals

Differential thermal analysis (DTA) was employed to monitor changes which occurred during heating of Fe-carbide and Fe-C mixtures. The DTA curves showed a relationship between endothermic peaks and phase transformations given in the Fe-C phase diagram. The transformations included (i) magnetic Fe to non-magnetic Fe, (ii) pure α-Fe to pure γ-Fe, (iii) γ + Fe3C → Liquid and (iv) pure γ-Fe to pure δ-Fe. Melting of the Fe-SiC powder compacts when sintered at temperatures higher than 1200°C was revealed and indicated by the endothermic peak of 1230°C. This peak corresponded to the transformation of γ + Fe3C → Liquid. That …

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Study Of Process Parameters In Conventional Powder Metallurgy Of Silver, S Amaranan, A Manonukul Jul 2010

Study Of Process Parameters In Conventional Powder Metallurgy Of Silver, S Amaranan, A Manonukul

Journal of Metals, Materials and Minerals

Compaction, sintering and physical properties of silver powder were investigated. The silver powder was uniaxially compacted into a cylindrical specimen using compaction pressures of 13.79, 27.58, 41.37 and 55.16 MPa. Compacted parts were sintered at 700, 800 and 900°C in argon atmospheres. In addition, compacted parts were also sintered in vacuum at 900°C. For the sintering temperatures of 700 and 800°C, it was found that the sintered density increased as the compaction pressure increased below 40 MPa, while the sintered density decreased at a compaction pressure above 40 MPa. At the sintering temperature of 900°C, the sintered density decreased with …

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Effects Of Replacing Binder With Powder Space Holder On Properties Of Metal Injection Moulded Foam, U Koikul, A Manonukul, S Suranuntchai Jul 2010

Effects Of Replacing Binder With Powder Space Holder On Properties Of Metal Injection Moulded Foam, U Koikul, A Manonukul, S Suranuntchai

Journal of Metals, Materials and Minerals

Metal foam can be produced using metal injection moulding with powder space holder. In this study, the effects of volume fraction of spacer holder on the foam properties were studied. Spherical poly (methyl methacrylate) (PMMA) particles were used as a space holder material. The 30% volume fraction of stainless steel 316L powder was mixed with varied volume fractions of binder and PMMA. There were five volume fractions of PMMA, namely 30% to 50%, with an increment of 5%. The results showed that the volume fraction of PMMA affected the properties. As the volume fraction of PMMA increased, the number of …

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Study Of Covering Conditions For Sintering Of Metal Injection Moulded Commercially Pure Titanium, N Muenya, A Manonukul Jul 2010

Study Of Covering Conditions For Sintering Of Metal Injection Moulded Commercially Pure Titanium, N Muenya, A Manonukul

Journal of Metals, Materials and Minerals

In metal injection moulding process, sintering for some specific materials is different from general materials. Titanium is a material that is not easy to sinter because it is a very reactive metal at high temperature. The high quality of the titanium component is difficult to control, especially so in point of the levels of carbon and oxygen, which have large effects on the mechanical properties. Commercially pure titanium was injected, debinded and sintered at 1150°C and 1250°C in high vacuum without a cover, and with a quartz cover, a mullite cover and an alumina cover, respectively. From the physical and …

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Comparison Of The Properties Of Portland Cement And Portland-Limestone Cement, Alex Lyatonga Mrema Jun 2010

Comparison Of The Properties Of Portland Cement And Portland-Limestone Cement, Alex Lyatonga Mrema

Tanzania Journal of Engineering and Technology (TJET)

A study was made in a cement factory in Dar es Salaam, Tanzania, where Ordinary Portland Cement (CEM I 42.5N) and Portland-limestone cement (PLC) which has the brand name Twiga Cement Extra (CEM II/A-L/32.5R) are produced and conforming to the Tanzania Standard TZS 727 (Part1): 2002, which is equivalent to EN 197 published by the committee for European normalization (CEN). A comparison was made between the two types of cements in terms of physical, chemical and mechanical properties. It was found out that they all complied with the standards, that there was no significant difference in their setting times and …

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The Effect Of Service Installations On Structural Integrity Of Slabs In Buildings, Ladislaus Lwambuka Jun 2010

The Effect Of Service Installations On Structural Integrity Of Slabs In Buildings, Ladislaus Lwambuka

Tanzania Journal of Engineering and Technology (TJET)

In building construction industry service installations, usually housed in conduit pipes, are commonly mounted inside reinforced concrete structural elements. This practice is adopted to attain aesthetical outlook at both interior and exterior surfaces of the buildings. Depending on the extent of service installations, the cross sectional area of the load bearing structural member is substantially reduced. However, the current structural design guidelines have no provision to accommodate the extent to which the existence of conduit pipes impairs the load bearing capacity of the structural element though reduced cross sectional area. This study has attempted to address this gap in structural …

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Development Of Pilot Plant For Bio-Ethanol Processing, Emrod Elisante Jun 2010

Development Of Pilot Plant For Bio-Ethanol Processing, Emrod Elisante

Tanzania Journal of Engineering and Technology (TJET)

The paper outlines achievements obtained in developing a pilot bio-ethanol plant at the Department of Chemical and Mining Engineering (CME), University of Dar es Salaam. The pilot plant consists of: 30 L inoculums tank; 1,700 L fermenter; 1,500 L/day distillation column; and ancillary equipment. The prototype is a platform intended to be used for technology demonstration and research by graduate and undergraduate students studying the production of bio-ethanol using traditional and non-traditional raw materials like coffee mash, cashew fruit, and sisal inulin. The equipment has been developed using locally available engineering resources and the distillation column with 18 sieve tray …

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A Study On Repairing Internal Defects Inside Concrete Using The Electrochemical Deposition Method, Weichung Yeih, Hui-Mi Hsu, Jiang-Jhy Chang, Chi-Che Hung, Rang Huang Jun 2010

A Study On Repairing Internal Defects Inside Concrete Using The Electrochemical Deposition Method, Weichung Yeih, Hui-Mi Hsu, Jiang-Jhy Chang, Chi-Che Hung, Rang Huang

Journal of Marine Science and Technology–Taiwan

In this paper, the feasibility of repairing internal defects inside concrete using the electrochemical deposition method is investigated. Various amounts of the air entrance agent (AEA) were added into fresh concrete to produce small air bubbles. Zinc sulfate was used as the electrolyte for the electrochemical deposition method. The dry unit-weight test, compressive strength test, splitting tensile strength test, four-probe electric resistivity, water absorption percentage test, open circuit potential test, scanning electronic microscope (SEM) and X-ray diffraction are carried out to investigate the repair results. Results show that the electrochemical deposition method is a promising rehabilitation method when internal defects …

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Developing An Analytical Model For The Optimal Capital Structure Of The Building Company, Lung-Ken Tsai, Hui-Ping Tserng, S. Ping Ho, Chiu-Wei Sung, Yeh-Shou Chou Jun 2010

Developing An Analytical Model For The Optimal Capital Structure Of The Building Company, Lung-Ken Tsai, Hui-Ping Tserng, S. Ping Ho, Chiu-Wei Sung, Yeh-Shou Chou

Journal of Marine Science and Technology–Taiwan

The characteristics and accounting principles of the building industry is different from those of other industries, so few studies have discussed the capital structure of the building industry. In this paper, the grey system theory and Pearson correlation analysis are used to study the capital structure (debt ratio) of building companies and its relationship with the company’s tax rate, non-debt tax shield, and operational risk, respectively. The results show that for building companies, non-debt tax shield has a positive correlation with the capital structure, whereas the operational risk has a very low correlation with the capital structure. The aforementioned results …

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Relative Importance Of Fire Resistance Performance Of Partition Walls, Ming-Chin Ho, Ming-Ju Tsai Jun 2010

Relative Importance Of Fire Resistance Performance Of Partition Walls, Ming-Chin Ho, Ming-Ju Tsai

Journal of Marine Science and Technology–Taiwan

The fire performance of partitions is influenced by the thickness, type, combustibility level of panel material, type of filling material and frame. However, realizing the importance of these parameters is not of enough help for interior designers. They need more quantitative information of the relative importance of the parameters so that they can select materials with cost consideration. Experiments were thus designed and analyzed by the Taguchi experimental design analysis method for it is good to determine the effect of each parameter especially as the number of parameters is large. Our data and analysis show that the thickness of panel …

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Probabilistic Assessment Of Seismic Drift Demands For Frame Structures In Near-Fault Regions, Jan Tysh-Shang, Lin Chiung-Yueh, Wu Chun-Wei Jun 2010

Probabilistic Assessment Of Seismic Drift Demands For Frame Structures In Near-Fault Regions, Jan Tysh-Shang, Lin Chiung-Yueh, Wu Chun-Wei

Journal of Marine Science and Technology–Taiwan

The purpose of this paper is to provide engineers with a rapid procedure to assess the maximum inter-story drift for generic moment-resisting frame (GMRF) structures in nearfault regions. In this procedure, the maximum inter-story drift demand of a structure can be evaluated by starting from the median value of elastic spectral displacement at the first period of the structure, and then amplifying it with some modification factors. Statistical parameters (medians and dispersions) of the distributions of these factors are obtained by performing linear, and nonlinear, dynamic simulations on codecompliant steel GMRF structures, to near-fault ground motions during Taiwan’s Chi-Chi earthquake …

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The Influence Of Broken Cables On The Structural Behavior Of Long-Span Cable-Stayed Bridges, Chin-Sheng Kao, Chang-Huan Kou Jun 2010

The Influence Of Broken Cables On The Structural Behavior Of Long-Span Cable-Stayed Bridges, Chin-Sheng Kao, Chang-Huan Kou

Journal of Marine Science and Technology–Taiwan

The influence of broken cables on the structural behavior of long-span cable-stayed bridges is examined considering all the nonlinear characteristics of a long-span cable-stayed bridge. The results show the influences of the broken cable on the structural behavior, such as the internal force, displacement, and the ultimate load-bearing capacity, are clear when an outside cable breaks. The results of the present study should assist in deciding when to replace cables in long-span cablestayed bridges.

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Direct Mapping Ovsf-Based Transmission Scheme For Underwater Acoustic Multimedia Communication, Chin-Feng Lin, Jiang-Yao Chen, Ya-Ju Yu, Jung-Ting Yan, Shung-Hyung Chang Jun 2010

Direct Mapping Ovsf-Based Transmission Scheme For Underwater Acoustic Multimedia Communication, Chin-Feng Lin, Jiang-Yao Chen, Ya-Ju Yu, Jung-Ting Yan, Shung-Hyung Chang

Journal of Marine Science and Technology–Taiwan

We would like to express our appreciation to the people that provided their help during this study. We also extend our appreciation to Dr. Chang-tai Shih, Visiting Professor of National Taiwan Ocean University from the Canadian Mu- seum of Nature, for his critical review and comments on the manuscript. This study was financially supported by a grant (NSC94-2313-B-019-018 and 94AS-14.1.1-FA-F1(16)) from the National Science Council of the Republic of China and the Fisheries Agency, Council of Agriculture, Taiwan, R.O.C.

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Genetic Algorithm-Based Chaos Clustering Approach For Nonlinear Optimization, Min-Yuan Cheng, Kuo-Yu Huang Jun 2010

Genetic Algorithm-Based Chaos Clustering Approach For Nonlinear Optimization, Min-Yuan Cheng, Kuo-Yu Huang

Journal of Marine Science and Technology–Taiwan

In this paper, a n-dimension convergence algorithm was employed to track the potential trend of evolution in traditional genetic algorithm (GA) by K-means clustering technique. And, chaotic algorithm was exploited to prevent the new approach from premature. By means of the proposed approach, not only the basic search capability was maintained but also the flexibility and efficiency of parametric modeling were improved. The main purpose of the paper is to demonstrate how the GA optimizer can be improved by incorporating a hybridization strategy. Experimental studies revealed that the hybrid chaotic approach with genetic algorithm (CGA) procedure could produce much more …

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Numerical Assessment Of A Space-Constrained Venting System With Multi-Chamber Plug Mufflers By Ga Method, Chiu Min-Chie, Chang Ying-Chun Jun 2010

Numerical Assessment Of A Space-Constrained Venting System With Multi-Chamber Plug Mufflers By Ga Method, Chiu Min-Chie, Chang Ying-Chun

Journal of Marine Science and Technology–Taiwan

Recently, research on new techniques of single-chamber plug silencers has been addressed. However, the assessment of a multi-chamber plug muffler’s optimal shape design within a constrained space as well as a pressure-drop limit which are mostly concerned with the necessity of operation and system venting in practical engineering work was rarely tackled. Therefore, this paper will not only analyze the sound transmission loss (STL) of a space-constrained multi-chamber plug muffler but also optimize the best design shape under a specified pressure drop. In this paper, the generalized decoupling technique and plane wave theory used to solve the coupled acoustical problem …

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Numerical Solutions Of Coastal Morphodynamic Evolution For Complex Topography, Chiang Yun-Chih, Hsiao Sung-Shan, Lin Ming-Chung Jun 2010

Numerical Solutions Of Coastal Morphodynamic Evolution For Complex Topography, Chiang Yun-Chih, Hsiao Sung-Shan, Lin Ming-Chung

Journal of Marine Science and Technology–Taiwan

Numerical modeling of coastal morphodynamic evolution is a powerful tool for the planning and design of coastal engineering. The coastal morphological modeling system is based on the sediment conservation law, which couples modules for waves, wave-driven currents, and sediment transport rates. The numerical scheme for the sediment conservation law and nonlinear coupling between these modules can lead to dispersions, diffusions, spurious oscillations and stability problems that are still not well developed. In this paper, the bedslope updating techniques, oscillation removal schemes, and 2-step, 3-time-level temporal discretization are employed to avoid oscillations and improve the stability of the coastal morphological model …

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Prediction Of Nonlinear System By Chaotic Modular, Wang Chin-Tsan, Chen Ji-Cong, Shaw Cheng-Kuang Jun 2010

Prediction Of Nonlinear System By Chaotic Modular, Wang Chin-Tsan, Chen Ji-Cong, Shaw Cheng-Kuang

Journal of Marine Science and Technology–Taiwan

Determining a suitable method of adequately predicting different nonlinear systems is necessary for instantaneous signal control. A chaotic modular found for realizing the prediction of signal control was applied to three different physical models: the Lorenz attractor, Chua’s circuit, and chaotic wake flow. Testing results from the three cases show that the behaviors of the nonlinear systems are predicted for instant signal control successfully. This evidence confirms that the chaotic module found by the authors is very useful for instant signal control and can be utilized as a tool for instantaneous prediction of nonlinear systems

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Laminar Flow Past An Oscillating Circular Cylinder In Cross Flow, Pham Anh-Hung, Lee Chang-Yeol, Seo Jang-Hoon, Chun Ho-Hwan, Kim Hee-Jung, Hyun-Sik Yoon, Dong-Woo Park, Il-Ryong Park Jun 2010

Laminar Flow Past An Oscillating Circular Cylinder In Cross Flow, Pham Anh-Hung, Lee Chang-Yeol, Seo Jang-Hoon, Chun Ho-Hwan, Kim Hee-Jung, Hyun-Sik Yoon, Dong-Woo Park, Il-Ryong Park

Journal of Marine Science and Technology–Taiwan

The present study numerically investigates the twodimensional laminar flow past a circular cylinder forced to oscillate transverse to the free-stream. The numerical simulations are performed at a various range of cylinder oscillation frequency ranged between 0.8 and 1.2 of the natural vortex shedding frequency, and the oscillation amplitude extended up to 50% of the cylinder diameter at one Reynolds number of 185 showing the typical two-dimensional vortex shedding. The immersed boundary method is used to handle the oscillating cylinder in a rectangular grid system using the finite volume method. The primary vortex shedding frequency has the same value with the …

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Navigation On A Great Ellipse, Tseng Wei-Kuo, Lee Hsuan-Shih Jun 2010

Navigation On A Great Ellipse, Tseng Wei-Kuo, Lee Hsuan-Shih

Journal of Marine Science and Technology–Taiwan

This paper presents contact formulae for the computation of the position, the distance, and the azimuth along a great ellipse. The proposed alternative formulae are to be primarily used for accurate sailing calculations on the ellipsoid in a GIS environment as in ECDIS and other ECS. Among the ECDIS Requirements is the need for a continuous system with a degree of accuracy consistent with the requirements of safe navigation. At present, this requirement is best fulfilled by the Global Positioning System (GPS). The GPS system is referenced to World Geodetic System 1984 (WGS 84) Datum. Using the ellipsoid model for …

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