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Full-Text Articles in Engineering

Determining The Cyclic Strength Of Geomaterials Under Low Frequency Cyclic Loading With Acoustic Emission, Helsin Wang, Ta-Peng Chang, Ju-Jiang Hung Dec 2010

Determining The Cyclic Strength Of Geomaterials Under Low Frequency Cyclic Loading With Acoustic Emission, Helsin Wang, Ta-Peng Chang, Ju-Jiang Hung

Journal of Marine Science and Technology

Acoustic emission is traditionally regarded as an explicit measurable index for microcracking in geomaterials. An accelerative cracking point is first introduced based on the different characteristics of acoustic emission at stable fracture propagation stage. Accelerative cracking point is located between the fracture initiation strength and critical energy release point, a point causing a fatal uncontrolled fracture in materials. Microcracking dominates the real mechanical characteristics in the materials, not reflected on the conventional mechanical experimental results as the stress level beyond the accelerative cracking point at the stable fracture propagation stage. At this stage, non-stress-controlled fracture in materials could arise as …


The Application Of E-Technology For Marine Information Service, Lien-Kwei Chien, Tsung-Shen Feng, Chieh-Cheng Yen, Beng-Chun Lee, Heng-Wen Chang Dec 2010

The Application Of E-Technology For Marine Information Service, Lien-Kwei Chien, Tsung-Shen Feng, Chieh-Cheng Yen, Beng-Chun Lee, Heng-Wen Chang

Journal of Marine Science and Technology

The purpose of this study is to establish the multi-function querying system by applying e-technology in marine data. Subjects tendency technology is new concept in system designing process of this study which originate from simulation language that was replace the structural technology. We also investigate the statistical characteristics of ocean waves and surges over Taiwan waters by cluster and return period analysis. Marine drifter track analysis and search area determination system were also analysis and import to GIS querying system. In order to make the locations of the near shore ships and sailing data could be easily convey through wireless …


Response Analysis Of Concrete Piles Subjected To Lateral Impact, Helsin Wang, Ta-Peng Chang, Jin-Jun Wang Dec 2010

Response Analysis Of Concrete Piles Subjected To Lateral Impact, Helsin Wang, Ta-Peng Chang, Jin-Jun Wang

Journal of Marine Science and Technology

One-dimensional wave theory is assumed to interpret longitudinal waves impulse response or impact echo testing results in concrete piles. Transient flexural waves tests are alternatively introduced to evaluate piles where the tops are inaccessible for conventional longitudinal wave testing. The resulting interpretation for flexural waves based on one-dimensional wave theory is improper due to various velocities at low frequencies. In this research, treating a pile as a waveguide, three-dimensional wave theory provides the dispersion relation between phase flexural velocity and frequency. Using the resonance solutions and first-mode flexural wave curve is a simple and efficient method to find the resonant …


Investigation On Vibration Energy Flow Characteristics In Coupled Plates By Visualizaiton Techniques, Kai Li, Sheng Li, De-You Zhao Dec 2010

Investigation On Vibration Energy Flow Characteristics In Coupled Plates By Visualizaiton Techniques, Kai Li, Sheng Li, De-You Zhao

Journal of Marine Science and Technology

The transmission and distribution of vibration energy flow in coupled plates are studied by the vibration intensity method together with visualization technique. Formulations for vibration intensity calculations and streamline representation, and the equations for energy flow are presented. The intensity vector, streamline map and energy distribution of coupled plates subject to a point force excitation are calculated and visualized to predict vibration energy transmission. The vibrational energy flows are very complex and dependent on the excitation frequencies, junction forms and boundaries. The energy sources, sinks, transmission paths and vortex fields are clearly shown with visualization technique. It is shown that …


Stability Assessment For The Undersea Gas Pipeline, Wen-Chien Tseng, Lien-Kwei Chien, Sheng-Tse Chuang, Pei-Chi Tsai, Ya-Ting Hsu, Ting-Ting Lu, Chu-Kuan Lin Dec 2010

Stability Assessment For The Undersea Gas Pipeline, Wen-Chien Tseng, Lien-Kwei Chien, Sheng-Tse Chuang, Pei-Chi Tsai, Ya-Ting Hsu, Ting-Ting Lu, Chu-Kuan Lin

Journal of Marine Science and Technology

In general, the activities of harbour district, coastal construction and re-transportation of tide and current are all possible to influence the stability of research area and sediment environment in nearshore area. It indicates that status of deposit property of seabed and variability of sediment environment are important factors to stability and safety for the path of undersea gas pipeline. An assessment procedure and approach for the prediction of the wave-induced and earthquake-induced liquefaction potential and erosion potential are proposed for marine engineering practice. The soil sample of this study is obtained from deposit zone of gas pipeline of seabed in …


A Time-Domain Analysis Of Wave Force On Small-Scale Cylinders Of Offshore Structures, Bao-Lei Geng, Bin Teng, De-Zhi Ning Dec 2010

A Time-Domain Analysis Of Wave Force On Small-Scale Cylinders Of Offshore Structures, Bao-Lei Geng, Bin Teng, De-Zhi Ning

Journal of Marine Science and Technology

To get the accurate wave loads on the small-scale cylinders on the platforms, not only the incident wave but also the diffraction and radiation wave should be considered. By taking the wave diffraction from a fixed large-scale cylinder as an example, wave loads on small-diameter cylinders in the diffraction wave field are calculated by Morison formula in this paper. A time-domain numerical model on wave diffraction from large-scale structures is developed with a higher-order boundary element method (HOBEM). Then the velocity and acceleration of any water particle in the fluid domain can be produced from the solved diffraction potential. Results …


Cooperation-Competition Model Of Transportation Construction Project From The Viewpoint Of Budget Allocation, Maw-Cherng Lin, Edward Ming-Yang Wu, Junn-Yuan Teng, Wen-Chih Huang Dec 2010

Cooperation-Competition Model Of Transportation Construction Project From The Viewpoint Of Budget Allocation, Maw-Cherng Lin, Edward Ming-Yang Wu, Junn-Yuan Teng, Wen-Chih Huang

Journal of Marine Science and Technology

Department of Marine Engineering, National Taiwan Ocean University, Keelung 202, Taiwan.


A Study Of Identifying Success Variables For Construction Partnering Via Sem Framework, Tung-Tsan Chen, Chih-Han Kao Oct 2010

A Study Of Identifying Success Variables For Construction Partnering Via Sem Framework, Tung-Tsan Chen, Chih-Han Kao

Journal of Marine Science and Technology

Owners and contractors in construction partnerships cooperate to quickly achieve results with reduced start-up costs, achieve a win-win result for both parties, increase efficiency, and reduce the possibility of conflict in construction projects. This study explored success variables (SVs) in construction partnerships via a novel framework. A questionnaire survey was distributed to experienced practitioners in the Taiwan construction industry. Factor analysis was applied to extract SVs based on the questionnaire results. Structural equation modeling (SEM) was then used to verify the relationships between the SVs identified in construction partnership. The analytical results showed that four success factors (SFs) in construction …


Optimal Estimation For Key Parameters Of The Marine Quality Model Using Data-Driven Neural Network, Ming-Chang Li, Shu-Xiu Liang, Zhao-Chen Sun, Guang-Yu Zhang Oct 2010

Optimal Estimation For Key Parameters Of The Marine Quality Model Using Data-Driven Neural Network, Ming-Chang Li, Shu-Xiu Liang, Zhao-Chen Sun, Guang-Yu Zhang

Journal of Marine Science and Technology

Marine water quality models are complicated because of their multi-parameter and multi-response characteristics. One major difficulty with water quality models is the accurate estimation of model parameters. In this paper, a new method based on a data-driven model (DDM) is developed to retrieve the value of model parameters. All training data are calculated by numerical water quality models from results of multiparameter matching design cases so the physical properties are not disturbed. The concept is to find the relationship between model parameters and the pollution concentration values of interior stations. Field data are imported into the relationship for inversing optimal …


Determination Of Interfaces In Soil Layers By Sound Wave Analysis With Cone Penetration Tests, Huei-Wen Chang, Tseng-Hung Chang, Viet-Tuong Nguyen, Chih-Wei Wang Oct 2010

Determination Of Interfaces In Soil Layers By Sound Wave Analysis With Cone Penetration Tests, Huei-Wen Chang, Tseng-Hung Chang, Viet-Tuong Nguyen, Chih-Wei Wang

Journal of Marine Science and Technology

This experimental study precisely identifies the soil layer interface using sound signals collected during cone penetration tests (CPTs). Using the high sensitivity of the sound sensor at the cone tip, this study effectively increases the accuracy in identifying the soil interface location. Shiluo sand and Jhongda Lateritic soil were used to construct large-scale soil layers. An acoustic CPT was applied to determine sound pressure and its root mean square (RMS). The Fourier spectrum and Hilbert-Huang transform (HHT) method were utilized and compared in their ability to analyze sound signals. The HHT method with a local energy-instantaneous frequencytime distribution performed well. …


Corrosion Behaviour Of Brass In The Vembanad Estuary, India, Andy Mathiazhagan, Rani Joseph, Kanjiramparayil Puthilon Narayanan, Palaniandy Seralathan Oct 2010

Corrosion Behaviour Of Brass In The Vembanad Estuary, India, Andy Mathiazhagan, Rani Joseph, Kanjiramparayil Puthilon Narayanan, Palaniandy Seralathan

Journal of Marine Science and Technology

Corrosion characteristics of brass panels were investigated in the Vembanad estuarine water (Cochin Harbor), India over a period of one year. The corrosion rate of brass samples during exposure was determined by gravimetric method and fouling on panels was assessed, exposure-wise, in terms of biomass. Corrosion products were identified by X-Ray diffraction. The results of the study were discussed in the light of the seawater characteristics.


A Wide Speed Range Sensorless Control Technique Of Brushless Dc Motors For Electric Propulsors, Min-Fu Hsieh, Hung-Ju Liao Oct 2010

A Wide Speed Range Sensorless Control Technique Of Brushless Dc Motors For Electric Propulsors, Min-Fu Hsieh, Hung-Ju Liao

Journal of Marine Science and Technology

This paper presents a sensorless drive technique for permanent-magnet brushless DC motors applied to electric propulsors of small ships or underwater vehicles. Propulsors enveloping electric motors (e.g., POD or subsea thrusters) have been increasingly applied due to their advantages of excellent maneuverability, high efficiency and low maintenance costs. To secure reliable operation under water, sensorless control is considered as an appropriate technique. However, conventional sensorless techniques often suffer problems of narrow speed range and low efficiency, particularly when the propulsors sustain heavy load at high speed operation. Hence, a sensorless technique with a wide speed range is developed in this …


The Study Of Ship Collision Avoidance Route Planning By Ant Colony Algorithm, Ming-Cheng Tsou, Chao-Kuang Hsueh Oct 2010

The Study Of Ship Collision Avoidance Route Planning By Ant Colony Algorithm, Ming-Cheng Tsou, Chao-Kuang Hsueh

Journal of Marine Science and Technology

Maritime traffic is becoming more complex every day. At present, due to technological advances and to new maritime regulations, there is increasing demand for new nautical marine instruments to be installed into the bridge, and the breadth of navigational information complicates on-duty officers’ decisions. Therefore, if decision support tools can be used to help deal with navigational decision-making, human errors arising from subjective judgments can be reduced, and sea transport safety improved. This research uses the concept of e-navigation as a framework, positioning collision avoidance path planning as the main theme, and applies an Ant Colony Algorithm (ACA) in the …


Maintenance Algorithm And Management System Of Sidewalk Facility, Lee-Kuo Lin, Chen-You Jian Oct 2010

Maintenance Algorithm And Management System Of Sidewalk Facility, Lee-Kuo Lin, Chen-You Jian

Journal of Marine Science and Technology

Sidewalk is one kind of infrastructure systems in each city, because every sidewalk facility is used by pedestrians, so the maintenance algorithm should be evaluated and worked with users’ role. To echo this reasonable concept, this research investigates several using influence factors, which were collected and evaluated from pedestrians. For statistical analysis, scientific tools including Delphi method, analytic hierarchy process (AHP), and fuzzy theory were used to analyze and establish a preliminary evaluation model of sidewalk maintenance system. In order to use this model pragmatically, this research also establishes a portable prototype system at PDA hardware. With this portable system, …


Risk Evaluation Of Ship Dynamic Stability In Regular Waves, Zhan-Jun Long, Seung-Keon Lee, Han-Suk Choi Aug 2010

Risk Evaluation Of Ship Dynamic Stability In Regular Waves, Zhan-Jun Long, Seung-Keon Lee, Han-Suk Choi

Journal of Marine Science and Technology

In this paper, a method combined with the existing approaches is proposed for evaluating and predicting the safety of ship rolling in regular waves. Based on the uncoupled equation of a single degree of freedom, the nonlinear ship rolling in waves is presented and the differential equation is integrated in the time domain by the fourth order Runge-Kutta algorithm. The erosion of the safe basins of a ship roll equation is simulated and the survival probability of a typical ship is studied according to the statistical and simulation results. The numerical results show that the survival probabilities of ship excited …


Reuse The Bed Ash From Circulating Fluidized Bed Combustion On Mortar Mixture, Hui-Mi Hsu, An Cheng, Sao-Jeng Chao Aug 2010

Reuse The Bed Ash From Circulating Fluidized Bed Combustion On Mortar Mixture, Hui-Mi Hsu, An Cheng, Sao-Jeng Chao

Journal of Marine Science and Technology

This paper investigates mortars consisting of various circulating fluidized bed combustion (CFBC) bed ash contents. The CFBC bed ash used in this study was obtained from Taiwan’s petroleum industry. This study presents experimental results on the flowability, compressive strength, drying shrinkage, scanning electronic microscopy (SEM) and mercury intrusion porosimetry (MIP) of mortar samples containing CFBC bed ash. The initial surface absorption tests (ISAT) and rapid chloride penetration test (RCPT) of mortar were used to measure water absorption and the ability to resist chloride ion characteristics for different mortar samples containing CFBC bed ash. CFBC bed ash is X-ray amorphous and …


Siphoning Sea Water Back Into The Engine In Fast Boats, Osman Azmi Ozsoysal Aug 2010

Siphoning Sea Water Back Into The Engine In Fast Boats, Osman Azmi Ozsoysal

Journal of Marine Science and Technology

A failure investigation has been conducted on the exhaust system of a high speed marine diesel engine in Turkish ambulance boats. Premature failures were reported on the poor starting, on the loss of power, on the lubricating oil leakage and on the engine overload. It was observed some significant tracks of sea water found its way into the exhaust passages from condensation of the salt water vapour and also from entering some sea water into the exhaust system. In order to initiate a more accurate cause investigation, the engine went through an overhaul inspection, in which it was determined that …


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

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 …


An Analytical Solution To The Modified Mild-Slope Equation For Waves Propagating Around A Circular Conical Island, Sung-Shan Hsiao, Chun-Ming Chang, Chih-Chung Wen Aug 2010

An Analytical Solution To The Modified Mild-Slope Equation For Waves Propagating Around A Circular Conical Island, Sung-Shan Hsiao, Chun-Ming Chang, Chih-Chung Wen

Journal of Marine Science and Technology

There are many analytical solutions to the mild-slope equation that employ Hunt’s direct solution of linear dispersion [7] to solve wave-scattering problems involving varying quiescent depths. The advantage of Hunt’s direct solution of linear dispersion is that it can extend the range of applicability of the mild-slope equation from long-wave to deep-wave conditions. However, because the bottom curvature and slope-squared terms are neglected, the mild-slope equation cannot preserve mass conservation. In this investigation, we derived an analytic solution of the modified mild-slope equation for a conical island by adopting Hunt’s direct solution of linear dispersion to be applicable to intermediate …


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

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 …


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

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 …


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

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 …


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

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 …


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

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 …


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

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 …


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

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.


Revisited To The Relationship Between The Free And Total Chloride Diffusivity In Concrete, Ming-Te Liang, Ran Huang, Hao-Yuan Jheng Jun 2010

Revisited To The Relationship Between The Free And Total Chloride Diffusivity In Concrete, Ming-Te Liang, Ran Huang, Hao-Yuan Jheng

Journal of Marine Science and Technology

The main purpose of this paper is provided the theoretical elucidation and parameter investigation for the experimental results performed by Lu et al. [Relationship between the free and total chloride diffusivity in concrete, Cement and Concrete Research, 32(2) 323~326 (2002)]. The analytical solution of Fick’s second law of linear diffusion in a semi-infinite quasi-homogeneous and isotropic concrete with initial and boundary conditions is used to curve fitting the experimental results and to find the relevant parameters such as the total and free chloride concentrations and diffusivities. The total chloride diffusivity is 2.8 times the free one. It seems plausible to …


A Risk Analysis Of Stevedoring Operations In Seaport Container Terminals, Kuo-Chung Shang, Wen-Jui Tseng Apr 2010

A Risk Analysis Of Stevedoring Operations In Seaport Container Terminals, Kuo-Chung Shang, Wen-Jui Tseng

Journal of Marine Science and Technology

This research is a study of container terminals in Kaohsiung Harbor and investigates risk management in the loading and unloading of container terminals. The study shows that the top three factors associated with severity of accident risk are: “Moving the crane without raising the lifting arm of the gantry crane, resulting in damage to the pilot’s compartment,” “Transferring containers direct to the trailers,” and, “As a result of climatic factors (typhoons), the facility takes no action to prevent collisions.” The top three factors associated with frequency of accident risk are, “Ships go by and waves cause a declined-body, raised prow …


Ahp Model For The Container Port Choice In The Multiple-Ports Region, Chien-Chang Chou Apr 2010

Ahp Model For The Container Port Choice In The Multiple-Ports Region, Chien-Chang Chou

Journal of Marine Science and Technology

In this paper, a theoretical analysis of the effect of surface roughness on the lubrication characteristics of inclined stepped composite bearings with micropolar fluid is examined. A generalized form of surface roughness is mathematically modeled by a stochastic random variable with non-zero mean, variance and skewness. The generalized average Reynolds type equation is derived for the rough inclined stepped composite bearings with micropolar fluid. The closed form expressions are obtained for the fluid film pressure, load carrying capacity, frictional force. These expressions can be utilized to obtain the performance characteristics of four different types of bearing system viz; rough plane …


Shape Optimization Of One-Chamber Mufflers With Reverse-Flow Ducts Using A Genetic Algorithm, Min-Chie Chiu Feb 2010

Shape Optimization Of One-Chamber Mufflers With Reverse-Flow Ducts Using A Genetic Algorithm, Min-Chie Chiu

Journal of Marine Science and Technology

Shape optimization on mufflers within a limited space is essential for industry where the equipment layout is occasionally tight and the available space for a muffler is limited for maintenance and operation purposes. To proficiently enhance the acoustical performance within a constrained space, the selection of an appropriate acoustical mechanism and optimizer becomes crucial. A one-chamber muffler hybridized with reverse-flow ducts which can visibly increase the acoustical performance is rarely addressed; therefore, the main purpose of this paper is to numerically analyze and maximize the acoustical performance of this muffler within a limited space. In this paper, the four-pole system …