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Integration Of Accounting-Based And Option-Based Models To Predict Construction Contractor Default, Lung-Ken Tsai, Hui-Ping Tserng, Hsien-Hsing Liao, Po-Cheng Chen, Wen-Pei Wang Oct 2012

Integration Of Accounting-Based And Option-Based Models To Predict Construction Contractor Default, Lung-Ken Tsai, Hui-Ping Tserng, Hsien-Hsing Liao, Po-Cheng Chen, Wen-Pei Wang

Journal of Marine Science and Technology

This paper aims to predict construction contractor default, which is excluded by most extant studies, due to the distinct characteristics of construction industry. Default predicting models developed in past literatures are mostly built by accounting information, yet accounting sheets have innate flaws. To calculate default probability, several recent studies applied the option pricing theory, which presumes that the stock market is efficient. This presumption isn't always true in real life. In this paper, a hybrid model is proposed. It combines information from both models by inputting the default probability from the option-based model into the accounting-based model. As the measure …


An Excited System Design For The Maximum Output Of Induction Generator Based On Vector Control, Ding-Tsair Su, Ying-Shing Shiao, Koan-Yuh Chang, Wen-Jer Chang Oct 2012

An Excited System Design For The Maximum Output Of Induction Generator Based On Vector Control, Ding-Tsair Su, Ying-Shing Shiao, Koan-Yuh Chang, Wen-Jer Chang

Journal of Marine Science and Technology

In this paper, without using the mechanical speed regulator, we propose a scheme that can control the output power of an induction generator by controlling the excited current. To attain this goal, an inverter is designed as a current controlled source, to supply an excited current for the induction generator. Furthermore, using the dq axes theory, a vector controller is designed by a digital signal processor (DSP) for controlling the inverter which supplies excited current appropriately in accordance with the wind speed to regulate the induction generator output power. Finally, the experimental results have shown good performances of the proposed …


Port Management Improvement Strategies Based On Simulation Model, Wen-Chih Huang, Tu-Cheng Kuo, Ching-Tsyr Wu, Cheng-Chen Kuo Oct 2012

Port Management Improvement Strategies Based On Simulation Model, Wen-Chih Huang, Tu-Cheng Kuo, Ching-Tsyr Wu, Cheng-Chen Kuo

Journal of Marine Science and Technology

Management performance of container terminal is an important factor of port competitiveness. In the past, ports had often increased performance by expanding the number of berths and equipment. However, recent global recession has significantly dampened the growth of the international trade. Thus, port authority must seek effective utilization of the capacities of its container terminals. Most ocean carriers in the Port of Kaohsiung in Taiwan rent multiple berths that are often dispersed to different container terminals, resulting in inefficient handling. Establishing terminal operators to optimize berth assignment may resolve this problem. The objective of this research is to construct a …


Behavior Of Regular Triangular Joints Under Cyclic Shearing, Shuh-Gi Chern, Tsu-Chiang Cheng, Wen-Ya Chen Oct 2012

Behavior Of Regular Triangular Joints Under Cyclic Shearing, Shuh-Gi Chern, Tsu-Chiang Cheng, Wen-Ya Chen

Journal of Marine Science and Technology

Synthetic regular triangular joints made of gypsum plaster were cyclicly sheared to measure asperity degradation and mathematical behavior of regular triangular joints. Laboratory cyclic shear tests were conducted for three joint types under three different normal stresses. Asperity degradation and shear strength of joints were found to be a function of joint roughness, normal stress, shearing displacement and number of loading cycles. Based on the experimental results, mathematical models were developed for evaluation of shear strength in cyclic loading conditions. Comparison of the test results with that of the proposed model, it was found a good agreement was observed.


Free Vibration Analysis Of A Hybrid Beam Composed Of Multiple Elastic Beam Segments And Elastic-Supported Rigid Bodies, Hsien-Yuan Lin, Chin-Yu Wang Oct 2012

Free Vibration Analysis Of A Hybrid Beam Composed Of Multiple Elastic Beam Segments And Elastic-Supported Rigid Bodies, Hsien-Yuan Lin, Chin-Yu Wang

Journal of Marine Science and Technology

This paper aims at presenting a method to determine the “exact” natural frequencies and mode shapes of a hybrid beam composed of multiple elastic beam segments and multiple rigid bodies with each rigid body connected with two adjacent elastic beam segments. Furthermore, each rigid body has its own mass and rotary inertia, and is supported by a translational spring and/or a rotational spring. First, based on the equations of the continuity of deformations and the equilibrium of moments and forces for each of the intermediate rigid bodies and boundary conditions, the coefficient matrices of the entire hybrid beam are derived. …


Performance Comparison Of The Stbc-Ofdm Decoders In A Fast Fading Channel, Chi-Min Li, Guo-Wei Li, Han-Yi Liu Oct 2012

Performance Comparison Of The Stbc-Ofdm Decoders In A Fast Fading Channel, Chi-Min Li, Guo-Wei Li, Han-Yi Liu

Journal of Marine Science and Technology

In a fast fading channel, the orthogonality of the two consecutive STBC-OFDM symbols will be destroyed and the received signals can not be perfectly separated. As a result, the bit error rate (BER) performance will be degraded seriously. In this paper, we analyze several co-channel interference (CCI) cancellation decoders for the STBC-OFDM in a fast fading channel including the Alamouti method, SIC method, ML method, DMLD method, and a proposed DZFD method. The proposed DZFD method has the advantage of reducing the computational complexity for the DMLD method. We also conduct the outdoor channel measurements to verify the CCI cancellation …


A Partition Dummy Sequence Insertion Papr Reduction Method Of The Ofdm System, Chi-Min Li, Jia-Chyi Wu, Chao-Chin Tseng Oct 2012

A Partition Dummy Sequence Insertion Papr Reduction Method Of The Ofdm System, Chi-Min Li, Jia-Chyi Wu, Chao-Chin Tseng

Journal of Marine Science and Technology

OFDM (Orthogonal Frequency Division Multiplexing) technique has been widely adopted in many wireless communication systems due to its high data-rate transmission ability and robustness to the multipath fading channel. One major drawback of the OFDM signal is the high peak-toaverage power ratio (PAPR) problem. The high PAPR results in the in-band distortion and out-of-band radiation when the OFDM signal is fed into a nonlinear power amplifier (PA). In this paper, we propose a partition dummy sequence insertion (PDSI) method to reduce the PAPR problem. Simulation results of the PAPR reduction and bit error rate (BER) performance for the proposed method …


Effects Of Non-Newtonian Couple Stresses On The Dynamic Characteristics Of Wide Rayleigh Step Slider Bearings, Jaw-Ren Lin, Li-Ming Chu, Wei-Liang Liaw Oct 2012

Effects Of Non-Newtonian Couple Stresses On The Dynamic Characteristics Of Wide Rayleigh Step Slider Bearings, Jaw-Ren Lin, Li-Ming Chu, Wei-Liang Liaw

Journal of Marine Science and Technology

To provide more information in fluid-film lubricated bearings, the effects of non-Newtonian couple stresses on the dynamic characteristics of Rayleigh step slider bearings have been presented in this paper. According to the results, the effects of non-Newtonian couple stresses signify an improvement in the bearing characteristics. Comparing with the Newtonian-lubricant Rayleigh step bearing, the nonNewtonian couple stress effects provide an increase in the steady load-carrying capacity, the dynamic stiffness coefficient and the dynamic damping coefficient, as well as a reduction in the steady volume flow rate required. In order to guide the use of the present study, a numerical example …


Optimal Dynamic Temporal-Spatial Paramter Inversion Methods For The Marine Integrated Element Water Quality Model Using A Data-Driven Neural Network, Ming-Chang Li, Shu-Xiu Liang, Zhao-Chen Sun, Guang-Yu Zhang Oct 2012

Optimal Dynamic Temporal-Spatial Paramter Inversion Methods For The Marine Integrated Element Water Quality Model Using A Data-Driven Neural Network, Ming-Chang Li, Shu-Xiu Liang, Zhao-Chen Sun, Guang-Yu Zhang

Journal of Marine Science and Technology

Certain marine water quality or ecosystem model parameters vary in space and time because of different plankton taxonomic compositions over a large domain. The same parameter vectors can result in suboptimal calibration. In the present paper, a data-driven model based on an artificial neural network is developed to inverse the values of model parameters dynamically. All training data used are calculated using numerical water quality models from the results of multiparameter matching design cases such that physical properties are not disturbed. The aim is to determine the relationship between the model parameters and the pollution concentration values of interior stations. …


Technology Forecasting Via Published Patent Applications And Patent Grants, Dar-Zen Chen, Chang-Pin Lin, Mu-Hsuan Huang, Yi-Tung Chan Aug 2012

Technology Forecasting Via Published Patent Applications And Patent Grants, Dar-Zen Chen, Chang-Pin Lin, Mu-Hsuan Huang, Yi-Tung Chan

Journal of Marine Science and Technology

The objective of this research is to study and establish the relationships between published patent applications and patent grants for exploring the technology development trend on a specific technology since more and more patents have their applications published before they are granted. Two modeling algorithms based on the patent grant/publish ratio as well as one long-term modeling algorithm based on the average publish-to-grant lag, were developed accordingly. The relationships between patent grants and published patent applications were constructed through two case studies on Magnetic Random Access Memory and Organic Light-Emitting Diode technologies and corresponding forecasts were then conducted. Comparing to …


Experimental Study Of The Electrochromic Properties Of Wo3 Thin Films Derived By Electrochemical Method, Chin-Guo Kuo, Chih-Yin Chou, Ya-Chieh Tung, Jung-Hsuan Chen Aug 2012

Experimental Study Of The Electrochromic Properties Of Wo3 Thin Films Derived By Electrochemical Method, Chin-Guo Kuo, Chih-Yin Chou, Ya-Chieh Tung, Jung-Hsuan Chen

Journal of Marine Science and Technology

This study aimed at the effect of electrolyte filled volume on transmittance and coloration efficiency of the electrochromic device. The device mainly consisted of ITO, WO3 template and electrolyte (PC + LiClO4). The experimental results showed the transmittance of visible light reduced with increasing the electrolyte filled volume. In addition, when the electrolyte filled volume was 100 mm3 , the coloration efficiency could reach the maximum CE, 15.2 cm2 /C.


Optimum Design Of Mufflers Hybridized With One-Connected Curved Tube Using The Boundary Element Method, Neural Networks, And The Genetic Algorithm, Ying-Chun Chang, Min-Chie Chiu, Ching-Chung Hsieh Aug 2012

Optimum Design Of Mufflers Hybridized With One-Connected Curved Tube Using The Boundary Element Method, Neural Networks, And The Genetic Algorithm, Ying-Chun Chang, Min-Chie Chiu, Ching-Chung Hsieh

Journal of Marine Science and Technology

Recently, research on new techniques for an economical muffler, which is hybridized with a single-connected curved tube, has been applied in the industrial field. Most researchers have explored noise reduction effects based on the transfer matrix method and the stiffness matrix method. However, the maximum noise reduction of a silencer within a constrained space, which frequently occurs in engineering problems, has been neglected. Therefore, the optimum design of mufflers becomes an essential issue. In this paper the shape optimization of a one-connected tube muffler with a fixed length is examined. In order to speed up the optimization assessment, a simplified …


Study On The Seismic Behavior Of Self-Anchored Suspension Bridges, Wen-Liang Qiu, Chang-Huan Kou, Chin-Sheng Kao, Shih-Wei Ma, Jiun Yang Aug 2012

Study On The Seismic Behavior Of Self-Anchored Suspension Bridges, Wen-Liang Qiu, Chang-Huan Kou, Chin-Sheng Kao, Shih-Wei Ma, Jiun Yang

Journal of Marine Science and Technology

The suspension bridge has a beautiful structural shape and an excellent spanning ability. The self-anchored suspension bridge has its main cables anchored directly on the two ends of the main girders, saving construction costs and time incurred during the anchorage construction of an earth-anchored suspension bridge. However, the feasibility of a self-anchored suspension bridge in a strong earthquake zone and the use of dampers to reduce seismic responses have yet to be fully investigated. Using the Yellow-River Road Bridge in Mainland as an example, this study sets out to analyze and investigate a series of seismic responses of a self-anchored …


An Arc Code To Predict The Thermal Crack Of Welded Sample, Je-Ee Ho Aug 2012

An Arc Code To Predict The Thermal Crack Of Welded Sample, Je-Ee Ho

Journal of Marine Science and Technology

In this study, a numerical code with enthalpy method in upwind scheme is proposed to estimate the distribution of thermal stress in the molten pool, which is primarily determined by the type of the input power and travel speed of heating source. To predict the cracker deficit inside the workpiece, a simulated program satisfying the diagonal domination and Scarborough criterion provides a stable iteration. Meanwhile, an experimental performance, operated by robot arm “DR-400” to provide a steady and continuous arc welding, was also conducted to verify the simulated result. By surveying the consistence of molten pool bounded by contrast shade …


Rust-Expansion-Crack Service Life Prediction Of Existing Reinforced Concrete Bridge/Viaduct Using Time-Dependent Reliability Analysis, Ming-Te Liang, Jiang-Jhy Chang, Han-Tung Chang, Chi-Jang Yeh Aug 2012

Rust-Expansion-Crack Service Life Prediction Of Existing Reinforced Concrete Bridge/Viaduct Using Time-Dependent Reliability Analysis, Ming-Te Liang, Jiang-Jhy Chang, Han-Tung Chang, Chi-Jang Yeh

Journal of Marine Science and Technology

It is necessary to develop a calculation method to help in the making of feasible, reliable, and serviceable predictions for the service lives of bridge or viaduct structures. This article presents the basis for doing rust-expansion-crack service life predictions for existing reinforced concrete (RC) bridges and viaducts in chloride-laden environments based on timedependant reliability modeling due to the corrosion of steel in concrete. The corrosion process has three stages, the initiation (diffusion or carbonation) time (ti = tc), the depassivation time (tp), and the propagation (corrosion) time (tcorr). The rustexpansion-crack service lives (tcr) of existing RC bridges or viaducts can …


Fuzzy Statistical Refinement For The Forecasting Of Tenders For Roadway Construction, Jeng-Wen Lin, Cheng-Wu Chen, Ting-Chang Hsu Aug 2012

Fuzzy Statistical Refinement For The Forecasting Of Tenders For Roadway Construction, Jeng-Wen Lin, Cheng-Wu Chen, Ting-Chang Hsu

Journal of Marine Science and Technology

Due to market competition, construction companies often place low bids when tenders are invited for domestic public construction projects. Over-competition can lead to vicious price wars to win a tender, which can in turn seriously affect the quality of construction. This study aims to establish an accurate Taiwan based model for the forecasting of the tendered price for roadway construction. This model is designed to assist the public sector to determine what would be a reasonable reserve price or award price. In order to ensure accurate predictions, a data classification system is established using fuzzy set theory. For each category …


Studies Of The Effect Of Diffusion-Induced Chloride Binding On Chlorination Life Predictions For Existing Reinforced Concrete Bridges, Ming-Te Liang, Jiang-Jhy Chang, Tung-Wei Yu Aug 2012

Studies Of The Effect Of Diffusion-Induced Chloride Binding On Chlorination Life Predictions For Existing Reinforced Concrete Bridges, Ming-Te Liang, Jiang-Jhy Chang, Tung-Wei Yu

Journal of Marine Science and Technology

The chloride ions diffusion is one of important factors of corrosion of reinforced concrete (RC) structures. The total chloride concentration penetrated into concrete can be expressed as the sum of bound and free chloride concentrations. The principal purpose of this paper is to study the chlorination life prediction of existing RC bridges due to chloride binding effect. The investigation method is that the no binding, linear binding, Langmuir and Freundlich adsorption isotherms are substituted into the analytical solutions of linear (diffusivity D = constant) and non-linear (D ≠ constant) diffusion equations associated with initial and boundary conditions, respectively. The chlorination …


Safety Stock Estimation Of Unit Load Devices For International Airline Operations, Hua-An Lu, Chien-Yi Chen Aug 2012

Safety Stock Estimation Of Unit Load Devices For International Airline Operations, Hua-An Lu, Chien-Yi Chen

Journal of Marine Science and Technology

Unit load devices (ULDs) are used to load air cargo and passengers’ checked baggage for wide-bodied aircraft operations. Since ULDs are reusable at the destination, airlines can invest in an appropriate fleet size for their requirements. The estimation of safety stock levels for every operating airport is a premeditated task because airlines must prepare enough devices for the outbound consignments of each flight. The variance of the number of used devices for each arrival and departure flight will influence the stock level of an airport. For scheduled international services, this study proposes an analytic method based on a cyclically time-sequenced …


A Manifold-Based Exponentially Convergent Algorithm For Solving Non-Linear Partial Differential Equations, Chein-Shan Liu Aug 2012

A Manifold-Based Exponentially Convergent Algorithm For Solving Non-Linear Partial Differential Equations, Chein-Shan Liu

Journal of Marine Science and Technology

For solving a non-linear system of algebraic equations of the type: Fi(xj) = 0, i, j = 1, …, n, a Newton-like algorithm is still the most popular one; however, it had some drawbacks as being locally convergent, sensitive to initial guess, and time consumption in finding the inversion of the Jacobian matrix ∂Fi /∂xj. Based-on a manifold defined in the space of (xi, t) we can derive a system of non-linear Ordinary Differential Equations (ODEs) in terms of the fictitious time-like variable t, and the residual error is exponentially decreased to zero along the path of x(t) by solving …


A Proposal On Standard Rudder Device Design Procedure By Investigation Of Rudder Design Process At Major Korean Shipyards, Hyun-Jun Kim, Sang-Hyun Kim, Jung-Keun Oh, Dae-Won Seo Aug 2012

A Proposal On Standard Rudder Device Design Procedure By Investigation Of Rudder Design Process At Major Korean Shipyards, Hyun-Jun Kim, Sang-Hyun Kim, Jung-Keun Oh, Dae-Won Seo

Journal of Marine Science and Technology

Recently, a very large vessel’s maneuvering performance, rudder performance and rudder design’s importance are considered to be an important subject. However, there have been few studies on the design process of rudder device before. The aim of this paper is to investigate a design process of rudder device and to propose a generalized design process of rudder device. Firstly, we investigated the rudder device design process of Korean major shipyards. And the differences of a torque calculation method, rudder section design, maneuvering performance examination method, etc. were analyzed theoretically. Secondly, the design process of rudder device was divided into concept …


Design Of Planning Level Ship Product Model For Ship Initial Design, Sungchul Shin, Soon-Sup Lee, Jong-Kap Lee, Kyung-Ho Lee Aug 2012

Design Of Planning Level Ship Product Model For Ship Initial Design, Sungchul Shin, Soon-Sup Lee, Jong-Kap Lee, Kyung-Ho Lee

Journal of Marine Science and Technology

This paper introduces a design of planning level ship product model (called SPPM hereinafter) based on ISO 10303 Standard for The Exchange of Product Model data (STEP). For the design of this model, the information modeling methodologies such as Integration Definition (IDEF) methods and Unified Modeling Language (UML) were reviewed, and a hybrid method was established. By using this method, ship initial design process was analyzed, and STEP-based information model and class libraries for SPPM were defined. For the data structure of this model, the shipbuilding Application Protocols (AP215, AP216 and Ship Common Model) of STEP were investigated and utilized …


Effective Asr Inhibiting Length And Applied Electrical Field Under Accelerated Lithium Migration Technique, Wei-Chien Wang, Chih-Chien Liu, Chau Lee Jun 2012

Effective Asr Inhibiting Length And Applied Electrical Field Under Accelerated Lithium Migration Technique, Wei-Chien Wang, Chih-Chien Liu, Chau Lee

Journal of Marine Science and Technology

This study investigates the effective concrete length and electric field strength during Accelerated Lithium Migration Technique (ALMT) application for the inhibition of the alkali-silica reaction (ASR). Concrete specimens measuring 10 cm in diameter and 5, 7, 9, 11, 14, 17, 20 and 23 cm in length are fabricated. Specimens with 5, 7, and 9 cm in length are applied 9 A/m2 constant current density, and the rest specimens are applied 60 V constant voltage. After the ALMT process, the specimen is cut every 0.5 cm and analyzed its cation content. Experimental results shows that if the aim of ASR inhibition …


Impact Abrasion Of Hydraulic Structures Concrete, Yu-Wen Liu, Shi-Wei Cho, Tsao-Hua Hsu Jun 2012

Impact Abrasion Of Hydraulic Structures Concrete, Yu-Wen Liu, Shi-Wei Cho, Tsao-Hua Hsu

Journal of Marine Science and Technology

Most of the abrasion damage is caused by the action of water-borne particles (silt, sand, gravel, and other solid) impacting and rolling against the concrete surface during hydraulic structure operation. In this paper solid-particle abrasion of concrete containing slag was studied. Experiments included use of river sand abrade of mean diameter ~ 0.6, 1.2, 2.5 and 5 mm, and sand content was 110, 230 and 340 kg per 1 m3 of water, impacting at 30°, 45° and 90° to the concrete surface. And the waterborne sand flow impact test method was used. Test results show that the abrasion rate to …


Prediction Model Of Air-Borne Salt Distribution In The Coastal Region Of Northern Taiwan, Yu-Sheng Chen, Hui-Jen Chiu, Yi-Wen Chan, Yung-Chang Chang, Chung-Chia Yang Jun 2012

Prediction Model Of Air-Borne Salt Distribution In The Coastal Region Of Northern Taiwan, Yu-Sheng Chen, Hui-Jen Chiu, Yi-Wen Chan, Yung-Chang Chang, Chung-Chia Yang

Journal of Marine Science and Technology

Taiwan is located in subtropical region, where temperature and humidity are relatively high all year round. Besides, the island is surrounded by ocean that the air-borne salt (ABS) attack is one of the major concerns for concrete structures. In this paper, a prediction model for the distribution of air-borne salt in the coastal region of northern Taiwan is proposed based on the result of ABS measurement at 38 sites near a period of four years. The ABS content was calculated monthly based on the salt concentration, water amount, time, and area of entrance. The monthly measured ABS of the entire …


Using Mercury Intrusion Porosimetry To Study The Interfacial Properties Of Cement-Based Materials, Shih-Wei Cho Jun 2012

Using Mercury Intrusion Porosimetry To Study The Interfacial Properties Of Cement-Based Materials, Shih-Wei Cho

Journal of Marine Science and Technology

Cement-based material is a typical porous composite material. Pore structures and interfacial properties of cementbased materials are influenced properties of ion transport behavior and durability. This study determines pore structure by employing mercury intrusion porosimetry (MIP), with mortar specimens manufactured with three different watercement (w/c) ratios and five volume proportions of fine aggregate to investigate interfacial properties. The experimental results show that total mercury intrusion decreases with an increase in sand volume proportion when comparing the same w/c ratio. The calculated mercury intrusion of interfacial transition zone increases with w/c and the volume proportion of fine aggregate.


Mechanical Properties Of Recycled Aggregate Concrete With Deformed Steel Re-Bar, Yongjae Kim, Jongsung Sim, Cheolwoo Park Jun 2012

Mechanical Properties Of Recycled Aggregate Concrete With Deformed Steel Re-Bar, Yongjae Kim, Jongsung Sim, Cheolwoo Park

Journal of Marine Science and Technology

This study investigates fundamental properties of the recycled aggregate which was produced through recent hi-technique of recycling. In addition, the mechanical properties of the concrete that was made by the recycled aggregate were compared to the concrete made of natural aggregate. The primary objective of this study was to characterize the concrete-rebar bonding properties of the recycled aggregate concrete. The recycled aggregate concrete showed about 18% decreased bond strength as compared to the natural aggregate concrete. The current prediction equation of bond strength suggested by the design specification does not consider this decreased bond strength by the use of the …


The Relationship Between Migration Time In Acmt And Ponding Time In Ponding Test For Cementitious Materials, Chung-Chia Yang, Yu-Ming Tsai, Kuo-Cheng Yang Jun 2012

The Relationship Between Migration Time In Acmt And Ponding Time In Ponding Test For Cementitious Materials, Chung-Chia Yang, Yu-Ming Tsai, Kuo-Cheng Yang

Journal of Marine Science and Technology

The objective of this study is to investigate the relationship between the diffusion behaviors of chloride ions and the migration of chloride ions in the cementitious materials. Different kinds of mortars with different binder combination (fly ash, slag and fly ash plus slag) and w/b ratios (w/b = 0.35, 0.45, 0.55, and 0.65) were used. In this study, the diffusion test and the migration test were carried out with the ponding test (AASHTO T259) and the accelerated chloride migration test (ACMT), respectively. The chloride profiles were obtained under different ponding time with ponding test and different migration time with ACMT. …


The Study Of Chloride Ion Transport Behavior Of Mortar Under Different Storing Environment Temperatures, Shih-Han Weng, Chung-Chia Yang, Shih-Wei Cho, Kuo-Cheng Yang Jun 2012

The Study Of Chloride Ion Transport Behavior Of Mortar Under Different Storing Environment Temperatures, Shih-Han Weng, Chung-Chia Yang, Shih-Wei Cho, Kuo-Cheng Yang

Journal of Marine Science and Technology

This study presents the chloride ion transport behavior of mortar from accelerated chloride migration test (ACMT). The water/cement ratio of mortars is 0.45, and the five volume fractions of fine aggregates (0%, 15%, 30%, 50% and 60%) were evaluated. After stored under different environment temperatures (25°C, 40°C, 60°Cand 80°C), the chloride ion passing through specimens was carried out with ACMT. From the Nernest-Planck equation and modified Fick’s second law, test data could be calculate the chloride migration coefficient of non-steady-state and steady-state. For mortar structure, dilution and tortuosity effects are positive effect to resist the penetration of Chloride ion. On …


Effect Of Water Soluble Polymer And Fiber On The Early-Age Shrinkage Cracking Of Cementitious Composites, Shih-Tang Lin, Ran Huang, Tsai-Lung Weng Jun 2012

Effect Of Water Soluble Polymer And Fiber On The Early-Age Shrinkage Cracking Of Cementitious Composites, Shih-Tang Lin, Ran Huang, Tsai-Lung Weng

Journal of Marine Science and Technology

Both polymeric fiber and water soluble polymer (WSP) have been reported effective in reducing early-age shrinkage cracking. The synergistic effect of cellulose based WSP and fiber on reducing early-age shrinkage cracking of cementitious composite exposed to a constant evaporation rate of 1 kg/(h.m2) environment was investigated in this paper. A fixed ratio of WSP was employed in the poly-acrylic fiber reinforced cementitious composites with various fiber content and aspect ratios. Results indicate that the addition of polymeric fibers reduced plastic shrinkage cracking, such as the total crack area, the average crack width and cracks wider than 1.5 mm. Further reductions …


Performance-Based Plastic Design And Energy-Based Evaluation Of Seismic Resistant Rc Moment Frame, Wen-Cheng Liao, Subhash C. Goel Jun 2012

Performance-Based Plastic Design And Energy-Based Evaluation Of Seismic Resistant Rc Moment Frame, Wen-Cheng Liao, Subhash C. Goel

Journal of Marine Science and Technology

This paper presents first time application of the Performance-Based Plastic Design (PBPD) approach to seismic resistant reinforced concrete special moment frames (RC SMF). Four baseline RC SMF (4, 8, 12 and 20-story) as used in the FEMA P695 were selected for this study. Those frames were redesigned by the PBPD approach. The baseline code designed frames and the PBPD frames were subjected to extensive inelastic pushover and time-history analyses. It turns out that the work-energy equation in PBPD to determine design base shear can also be used to estimate seismic demands, herein called the energy spectrum method. In summary, this …