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Articles 19921 - 19950 of 27539

Full-Text Articles in Engineering

Lamellar Directed Self Self-Assembly Using Ps-B-Pmma Block Copolymers, Jacob P. Kupernik May 2016

Lamellar Directed Self Self-Assembly Using Ps-B-Pmma Block Copolymers, Jacob P. Kupernik

Journal of the Microelectronic Engineering Conference

The goal of this senior design project was to develop a DSA process for the RIT SMFL and enable further research and teaching opportunities. The objective of this project was to achieve lamellar structure formation using a PS-b-PMMA BCP annealed thermally and in solvent vapor. Thermal annealing of the samples resulted in destructive film oxidation. SVA was carried out on the samples using both toluene and THF and the pattern was revealed using an oxygen RIE. No significant changes in pattern morphology were noted when comparing the toluene and THF SVA processes. Final patterns were observed using the RIT Nano-Imaging …

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Directed Self-Assembly Using Ps-B-Pmma Block Copolymers, Jacob Kupernik May 2016

Directed Self-Assembly Using Ps-B-Pmma Block Copolymers, Jacob Kupernik

Journal of the Microelectronic Engineering Conference

No abstract provided.

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Direct Write Optical Waveguide Fabrication In Organic Films Using A Heidelberg Laser Writer, Ryan Moss May 2016

Direct Write Optical Waveguide Fabrication In Organic Films Using A Heidelberg Laser Writer, Ryan Moss

Journal of the Microelectronic Engineering Conference

Fabrication and characterization of mr-DWL photoresist buried channel waveguides on glass is carried out using the Heidelberg DWL 66+ (a laser direct write system). Waveguides are formed of mr-DWL-5 on glass with a spun on cladding material Norland Optical Adhesive-65(NOA- 65). The optical waveguides are successfully coupled at 650nm, and resonance structures tested at 710nm. Ring resonators with nominal spacing of .9um and a radius of 350um have an approximate quality factor of 71k .

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Ferroelectric Hfo2 Thin Films For Fefet Memory Devices, Joe Mcglone May 2016

Ferroelectric Hfo2 Thin Films For Fefet Memory Devices, Joe Mcglone

Journal of the Microelectronic Engineering Conference

No abstract provided.

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Bs News May/June May 2016

Bs News May/June

Building Services Engineering

No abstract provided.

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Special Issue: Electrocatalyst And Electrocatalysis In Fuel Cells Preface, Zi-Dong Wei Apr 2016

Special Issue: Electrocatalyst And Electrocatalysis In Fuel Cells Preface, Zi-Dong Wei

Journal of Electrochemistry

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Recent Progress In Non-Precious Metal Oxygen Reduction Reaction Catalysts With An Encapsulation Structure, Mei-Ling Xiao, Jian-Bing Zhu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing Apr 2016

Recent Progress In Non-Precious Metal Oxygen Reduction Reaction Catalysts With An Encapsulation Structure, Mei-Ling Xiao, Jian-Bing Zhu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing

Journal of Electrochemistry

Platinum-based materials, the state-of-the-art catalysts for fuel cells, suffer from prohibitive costs, limited resources and insufficient durability. Accordingly, tremendous efforts were made in searching for efficient, durable and inexpensive alternatives to precious-metal electrocatalysts for the oxygen reduction reaction (ORR). Transition-metals (Fe, Co)/nitrogen co-doped hybrids, heteroatom (N, P, S, F, et al) doped carbons and composites with transition-metals encapsulated in graphitic layers are reported as the most efficient non-precious metal ORR catalysts. Among the various non-precious metal ORR catalysts, transition-metals encased in graphitic layer catalysts are a novel type of catalysts for ORR with high activity and durability, and thus, the …

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Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Shang Li, Fen Zhou, Lei Chen, Mu Pan Apr 2016

Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Shang Li, Fen Zhou, Lei Chen, Mu Pan

Journal of Electrochemistry

It is an urgent need to reduce the Pt loading in electrode for practical fuel cell applications worldwide. Herein, we theoretically investigate the oxygen distribution, generated current, and minimum Pt loading of Pt/C electrode for practical applications based on kinetic model of oxygen reduction reaction. The results indicate that with increasing electrode effective thickness to 40 mm, serious concentration polarization is expected for Pt/C electrode. To generate a power density of 1.4 W⋅cm-2 (2.1A⋅cm-2@0.67 V) for fuel cell, the cathode catalyst layer thickness in PEMFC should be as thin as 3 mm. The minimum Pt loading will …

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Multi-Scaled Carbon Supported Platinum As A Stable Electrocatalyst For Oxygen Reduction Reaction, Yu-Ping Li, Lu-Hua Jiang, Su-Li Wang, Gong-Quan Sun Apr 2016

Multi-Scaled Carbon Supported Platinum As A Stable Electrocatalyst For Oxygen Reduction Reaction, Yu-Ping Li, Lu-Hua Jiang, Su-Li Wang, Gong-Quan Sun

Journal of Electrochemistry

The stability of carbon supports is essential for electrocatalysts of fuel cells. Herein, the mesoporous carbon with the high graphitic degree (highly graphitic mesoporous carbon, HGMC) was synthesized by using resorcinol as the carbon precursor, SiO2 as the templates and urea as the reducing agent. The as-prepared HGMC was characterized by XRD, Raman spectroscopy, TEM, N2 adsorption. The stability of HGMC was evaluated by mimicking the start-up/shut-down conditions of fuel cells in a three-electrode system referring to the NREL standard. The obtained HGMC is of moderate surface area (187.4 m2•g-1) and is chemically stable under …

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Recycling Mf Solid Waste Into Mesoporous Nitrogen-Doped Carbon With Iron Carbide Complex In Graphitic Layers As An Efficient Catalyst For Oxygen Reduction Reaction, Can-Yun Zhao, Lin Huang, Yong You, Ying-Fang Yao, Xiao-Gang Su, Hong Wan, Jian-Guo Liu, Cong-Ping Wu Apr 2016

Recycling Mf Solid Waste Into Mesoporous Nitrogen-Doped Carbon With Iron Carbide Complex In Graphitic Layers As An Efficient Catalyst For Oxygen Reduction Reaction, Can-Yun Zhao, Lin Huang, Yong You, Ying-Fang Yao, Xiao-Gang Su, Hong Wan, Jian-Guo Liu, Cong-Ping Wu

Journal of Electrochemistry

Nitrogen-doped carbon materials with iron ions are known as catalytic growth agents for the oxygen reduction reaction (ORR) in fuel cells, but the design and synthesis of high-performance and low-cost catalysts still remain a significant challenge. Herein, we present a cost-effective approach to dispose of MF solid waste as the precursor for the synthesis of MCFes catalyst with the favorable structure features such as the high specific surface area, abundant active sites and suitable pore structure. The results showed that the MCFe-10/10/2 had specific surface area as high as 780.7 m2•g-1 and high efficient catalytic activity comparable …

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Recent Progresses In Molybdenum-Based Electrocatalysts For The Hydrogen Evolution Reaction, Ze-Xing Wu, Jie Wang, Jun-Po Guo, Jing Zhu, De-Li Wang Apr 2016

Recent Progresses In Molybdenum-Based Electrocatalysts For The Hydrogen Evolution Reaction, Ze-Xing Wu, Jie Wang, Jun-Po Guo, Jing Zhu, De-Li Wang

Journal of Electrochemistry

Electrochemical catalytic production of hydrogen has been considered as a promising and sustainable strategy for clean and renewable energy technologies. Molybdenum-based non noble metal catalysts for the hydrogen evolution reaction have attracted extensive attention due to its effective catalytic performance. In this review, the recent progresses in molybdenum-carbide, phosphide, nitride and sulfide electrocatalysts are presented. In addition, the strategies to improve the catalytic performance are analyzed and the prospects for the future development trends are expected.

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Rambling Between "Zhong Yong" And "Catalysis", Zi-Dong Wei Apr 2016

Rambling Between "Zhong Yong" And "Catalysis", Zi-Dong Wei

Journal of Electrochemistry

“Zhong Yong” represents a traditional Chinese wisdom, which was first proposed by Confucius and continuously richened by his followers. “Zhong Yong” pursues the balances among all kinds of contradictions, and insists that neither “too much” nor “not enough” is good. For a successful catalyst, on which the adsorption of reactants must be not so strong and not so weak either. On this point of view, there are the same pursuits for “Zhong Yong” and catalysis. In this paper, the author starts his story with a conversation between Confucius and his student, followed by 3 interesting stories happening in the ancient …

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Synthesis Of Structurally Ordered Platinum-Iron Catalysts With Enhanced Oxygen Reduction Reaction Activity, Ye-Zheng Cai, Ming-Chuan Luo, Fang-Hui Wang, Zhao-Nan Sun, Hong Zhu Apr 2016

Synthesis Of Structurally Ordered Platinum-Iron Catalysts With Enhanced Oxygen Reduction Reaction Activity, Ye-Zheng Cai, Ming-Chuan Luo, Fang-Hui Wang, Zhao-Nan Sun, Hong Zhu

Journal of Electrochemistry

To improve oxygen reduction reaction catalytic activity of the precious metals platinum for fuel cell, the precursors of carbon-supported structurally disordered platinum-iron alloy (D-Pt3Fe/C and D-PtFe/C) catalysts with different compositions were synthesized via a modified polyol reduction method. Then, by optimizing the annealing conditions in the inert gas, we turned the structurally disordered platinum-iron alloy to the structurally ordered platinum-iron alloy (O-Pt3Fe/C and O-PtFe/C) catalysts. The structural characterizations of the as-prepared catalysts were performed by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS). The results …

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Mini-Review: Possible Applications Of Scanning Electrochemical Microscopy (Secm) In Characterizations Of Oxygen Reduction Reaction And Oxygen Evolution Reaction, Xing-Xing Chen Apr 2016

Mini-Review: Possible Applications Of Scanning Electrochemical Microscopy (Secm) In Characterizations Of Oxygen Reduction Reaction And Oxygen Evolution Reaction, Xing-Xing Chen

Journal of Electrochemistry

Scanning electrochemical microscopy (SECM) has been proved to be a unique technique for combinatorial screening of localized phenomena for different electrocatalysts potentially used in new energy conversion and storage systems. This mini-review provides a brief summary of different SECM working modes, such as direct mode, feedback mode, generation-collection mode, redox competition mode and noise mode, which are especially applied for characterizing the oxygen reactions. Particularly, a series of important development in SECM screening of electrocatalysts for oxygen reduction reaction and oxygen evolution reaction from the author and W. Schuhmann’s group in Germany has been highlighted and overviewed. Finally, some prospects …

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Syntheses Of Carbon Paper Supported High-Index Faceted Pt Nanoparticles And Their Performance In Direct Formic Acid Fuel Cells, Long Huang, Mei Zhan, Yu-Cheng Wang, Yan-Fen Lin, Shuo Liu, Ting Yuan, Hui Yang, Shi-Gang Sun Apr 2016

Syntheses Of Carbon Paper Supported High-Index Faceted Pt Nanoparticles And Their Performance In Direct Formic Acid Fuel Cells, Long Huang, Mei Zhan, Yu-Cheng Wang, Yan-Fen Lin, Shuo Liu, Ting Yuan, Hui Yang, Shi-Gang Sun

Journal of Electrochemistry

Direct formic acid fuel fuels (DFAFCs) are promising energy source for portable electronic devices. Palladium (Pd) is more active than platinum (Pt) for the formic acid electrooxidation. However, the stability of Pd is much poorer than that of Pt. Unfortunately, the ultra-low natural abundance of the Pt makes it extremely expensive and limits its application as a fuel cell catalyst. Boosting both the activity and stability of Pt nanoparticles to enhance their efficiency is urgent. As previous works illustrated, nanoparticles enclosed with high-index facets usually bare a higher activity toward fuel cell related reactions than those nanoparticles with low-index facet. …

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Preparation Parameters Optimization And Electrocatalytic Properties Of Supported Au Nanoparticles, Rui Yao, Yu-Jiang Song, Huan-Qiao Li, Jia Li, Jian-Guo Liu Apr 2016

Preparation Parameters Optimization And Electrocatalytic Properties Of Supported Au Nanoparticles, Rui Yao, Yu-Jiang Song, Huan-Qiao Li, Jia Li, Jian-Guo Liu

Journal of Electrochemistry

Due to interesting size effect, physical and chemical properties, nano-scale gold materials have been commonly used to catalytic reactions. However, the application of gold nanomaterials in the field of electrocatalysis is limited. Herein, we report the synthesis of gold nanparticles supported on carbon through chemical reduction of HAuCl4 by NaBH4 under mild conditions in the presence of surfactants as soft templates, carbon black or graphene as a support. We investigated a series of key reaction parameters, including reagent concentration, temperature, the types of carbon supports and surfactants. With the optimum synthetic parameters, we successfully obtained supported 1 ~ …

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Preparation And Performance Of 3d Graphene Type Porous Carbon Employing Nano Fe(Oh)3 As Template For Oxygen Reduction Catalyst, Chong-Yun Sun, Zhong-Fang Li, Xue-Wei Lu, Xi-Zhan Zhong, Yu-Rong Liu Apr 2016

Preparation And Performance Of 3d Graphene Type Porous Carbon Employing Nano Fe(Oh)3 As Template For Oxygen Reduction Catalyst, Chong-Yun Sun, Zhong-Fang Li, Xue-Wei Lu, Xi-Zhan Zhong, Yu-Rong Liu

Journal of Electrochemistry

The 3D graphene type porous carbon was prepared using coal tar pitch as carbon source and nano Fe(OH)3 as template. Optimal conditions for the catalytic oxygen reduction performance were determined as: the mass ratio of coal tar, nano Fe(OH)3 and KOH is 6:8:4; the pyrolysis temperature is 800 oC. SEM images show that the products have uniformly porous structure. TEM images demonstrate that the products are porous with foam shapes. HRTEM images further indicate that the products have formed several-layers 3D graphene structure, which are also supported by XRD and Raman data, and the pore size mainly …

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Nitrogen, Fluorine Co-Doped Silk-Derived Carbon For Electrochemical Oxygen Reduction With High Performance In Alkaline Solution, Fang-Fang Liu, Hong-Liang Peng, Shi-Jun Liao Apr 2016

Nitrogen, Fluorine Co-Doped Silk-Derived Carbon For Electrochemical Oxygen Reduction With High Performance In Alkaline Solution, Fang-Fang Liu, Hong-Liang Peng, Shi-Jun Liao

Journal of Electrochemistry

A high-performance, doped carbon-based catalyst was synthesized by pyrolyzing hydrothermally treated silkworm cocoon. The effects of preparation conditions and fluorine promotion on various catalysts’ performance were investigated. The catalyst prepared under optimal conditions and doped with nitrogen and fluorine possessed the high specific surface area of more than 1000 m2⋅g-1 and contained 3.5 and 7.3% (by mass, the same below) N and F, respectively. The activity of the catalyst toward oxygen reduction reaction in an alkaline medium was comparable to that of commercial Pt/C, showing both superior tolerance to methanol poisoning and better durability. Doping with fluorine …

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Engineering Students Attend International Summit: Engineers Without Borders On Un Sustainable Development Goals, Sarah Brockett Apr 2016

Engineering Students Attend International Summit: Engineers Without Borders On Un Sustainable Development Goals, Sarah Brockett

Andrews Agenda: Campus News

No abstract provided.

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Pilot Source Study 2015: Us Regional Airline Pilot Hiring Background Characteristic Changes Consequent To Public Law 111-216 And The Faa First Officer Qualifications Rule, Elizabeth Bjerke, Guy Smith, Maryjo Smith, Cody Christensen, Thomas Carney, Paul Craig, Mary Niemczyk Apr 2016

Pilot Source Study 2015: Us Regional Airline Pilot Hiring Background Characteristic Changes Consequent To Public Law 111-216 And The Faa First Officer Qualifications Rule, Elizabeth Bjerke, Guy Smith, Maryjo Smith, Cody Christensen, Thomas Carney, Paul Craig, Mary Niemczyk

Journal of Aviation Technology and Engineering

This report is the first article in a series called Pilot Source Study 2015. Public Law (PL) 111-216, passed by the US Congress in 2010, and the subsequent FAA Regulation, Pilot Certification and Qualification Requirements for Air Carrier Operations Rule, abruptly changed the pilot hiring situation for US air carriers operating under 14 CFR Part 121. PL 111-216 became effective on August 1, 2013; thereafter, pilots were not eligible to be first officers in Part 121 air carriers unless they were certificated as Air Transport Pilots (ATP) with 1,500 hours of flight time, with some flight hour reductions for …

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Corrosion Of Rebar Under Carbonation And Salt Environment, Wei-Chung Yeih, Jiang-Jhy Chang, Yu-Ping Huang, Ran Huang Apr 2016

Corrosion Of Rebar Under Carbonation And Salt Environment, Wei-Chung Yeih, Jiang-Jhy Chang, Yu-Ping Huang, Ran Huang

Journal of Marine Science and Technology–Taiwan

In this study, the behavior of reinforced concrete under carbonation and in a salt environment was investigated. Three types of cements- Type I cement, Type II cement and highalumina cement (HAC) - were used to study the influence of cement on reinforced concrete behavior. To simulate chloridecontaminated concrete, 1% NaCl (by cement weight) was added to some groups of specimens. Results revealed that the carbonation released chloride ions from Friedel's salt, which increased the chloride content near the carbonation front. The carbonation rate of HAC concrete was higher than that of Type I and Type II cement concrete. The corrosion …

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Effect Of Battery Energy Storage Systems On The Value Of An Intermittent Wind Energy Source In Isolated Systems, Chun-Lung Chen Apr 2016

Effect Of Battery Energy Storage Systems On The Value Of An Intermittent Wind Energy Source In Isolated Systems, Chun-Lung Chen

Journal of Marine Science and Technology–Taiwan

The increase in environmental protection awareness and the progressive exhaustion of conventional fossil energy sources have increased interests in integrating wind energy sources into existing power systems. Despite the various benefits of wind power, the intermittency and unpredictability of wind power generation cause operational concerns and waste usable capacity as the installation of the wind generation sources increases. To enhance the value of an intermittent wind energy source by using a battery energy storage system (BESS), an iterative algorithm that combines improved dynamic programming and a hybrid direct search method were developed for solving the optimal wind-thermal-battery coordination scheduling (WTBCS) …

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Hydraulic System Design And Structural Analysis Of A Bop Gantry Crane, Hyun-Ji Kim, Gwi-Nam Kim, Chang-Kweon Jeong, Young-Hwan Yoon, Yong-Gil Jung, Sun-Chul Huh Apr 2016

Hydraulic System Design And Structural Analysis Of A Bop Gantry Crane, Hyun-Ji Kim, Gwi-Nam Kim, Chang-Kweon Jeong, Young-Hwan Yoon, Yong-Gil Jung, Sun-Chul Huh

Journal of Marine Science and Technology–Taiwan

A blowout preventer (BOP) gantry crane is an offshore plant that moves a BOP stack located on a drilling platform to a BOP trolley. However, such a plant has yet to be developed in Korea. Because BOP gantry cranes produced overseas are expensive, developing such cranes domestically is imperative. In this study, ANSYS was used to conduct a structural analysis on a BOP gantry crane model to simulate the roll and pitch motions of a drillship that were induced by waves and wind load as well as the weight of the crane. Moreover, Simulation X was used for implementing control-system …

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Using Principal Component Analysis With A Back-Propagation Neural Network To Predict Industrial Building Construction Duration, Sou-Sen Leu, Chi-Min Liu Apr 2016

Using Principal Component Analysis With A Back-Propagation Neural Network To Predict Industrial Building Construction Duration, Sou-Sen Leu, Chi-Min Liu

Journal of Marine Science and Technology–Taiwan

Industrial businesses must respond efficiently to market demands; therefore, industrial construction must accurately predict the project duration at the pre-investment stage. In practice, project duration predictions rely on the experience of project managers. To provide impartial expertise and quantitative estimate the predicted duration of constructing an industrial building, an extensive history of industrial building cases were collected to form a database. Principal component analysis was applied to the database to identify key factors to serve as input data for a back-propagation neural network (BP-NN) that was used to estimate the project duration. Three prediction models were identified and developed separately …

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Carbonation Resistance Of Concrete With Mortar Coating, Wen-Hu Tsao, Ming-Te Liang, Nai-Ming Huang, Ke-Hung Liao Apr 2016

Carbonation Resistance Of Concrete With Mortar Coating, Wen-Hu Tsao, Ming-Te Liang, Nai-Ming Huang, Ke-Hung Liao

Journal of Marine Science and Technology–Taiwan

The principal purpose of this paper was theoretically to study the carbonation resistance of a semi-infinite medium which concrete has a mortar coating having diffusion properties different from those of the rest of the medium. The analytical solution of a semi-infinite composite medium was used to predict the time required for subsidence due to concrete with mortar coating. The inaccurate analytical solution was published in previous books. Thus, the analytical solution of a semi-infinite composite medium is re-derived in this article. The governing equations without initial and boundary conditions in the previous books are also pointed out. In order to …

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Effect Of Cooling Rate During Solution Heat Treatment On The Microstructure And Mechanical Properties Of Sp-700 Titanium Alloys, Jo-Kuang Nieh, Chih-Ting Wu, Yen-Lin Chen, Chao-Nan Wei, Sheng-Long Lee Apr 2016

Effect Of Cooling Rate During Solution Heat Treatment On The Microstructure And Mechanical Properties Of Sp-700 Titanium Alloys, Jo-Kuang Nieh, Chih-Ting Wu, Yen-Lin Chen, Chao-Nan Wei, Sheng-Long Lee

Journal of Marine Science and Technology–Taiwan

The relationship between the microstructures and the mechanical properties of solution-treated SP-700 titanium alloys, as obtained with different cooling rates, was investigated. The results indicate that the water-quenched alloy contains the primary  (p), ”-martensite and residual  (r) phases. Aging heat treatment can convert both ”-martensite and the r phases to the fine-grained  +  equilibrium phases, resulting in a significant increase in tensile strength and hardness. Both the air-cooled and furnace-cooled alloys consist of the p,  and  phases. The air-cooled alloy containing the fine-grained  phase has relatively higher hardness. Aging heat treatment causes only …

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Side Friction Of Drilled Piles In Cobble Layers, Tien-Kuen Huang, Chih-Yi Yang Apr 2016

Side Friction Of Drilled Piles In Cobble Layers, Tien-Kuen Huang, Chih-Yi Yang

Journal of Marine Science and Technology–Taiwan

Full scale vertical load tests have been carried out on drilled piles in cobble layers to evaluate side friction capacity. In the finite element analysis, firstly the property of pile is assumed linear elastic and the elastic-plastic Mohr-Coulomb model is used for the cobble layer. Interface elements are introduced to model interface interaction between pile and cobble layer. The measured data obtained from the field tests are compared with the finite element simulation results using PLAXIS 2D. It shows reasonable agreement between field test data and simulation results. A preliminary evaluation of side friction of drilled piles in cobble layers …

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Maximum-Likelihood Directivity For Depicting Perceptual Contours, Chun-Shun Tseng, Jung-Hua Wang, Ren-Jie Huang Apr 2016

Maximum-Likelihood Directivity For Depicting Perceptual Contours, Chun-Shun Tseng, Jung-Hua Wang, Ren-Jie Huang

Journal of Marine Science and Technology–Taiwan

This paper presents a novel method based on MaximumLikelihood Estimation (MLE) to evaluate pixel directivity for depicting image contours of objects as perceived by human eyes. The method is characterized by employing discrete masks with different shapes centered at a target pixel to sample gradient orientations of neighboring pixels for evaluating directivity of the target pixel, and applying MLE to determine one of these discrete sampling masks that best fits the orientation similarity of the target pixel. We show that such a fitting process in effect fulfils the similarity and proximity laws in Gestalt theory, and a salient alignment location …

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Efficiently Mining Frequent Itemsets In Transactional Databases, Salah Alghyaline, Jun-Wei Hsieh, Jim Z. C Lai Apr 2016

Efficiently Mining Frequent Itemsets In Transactional Databases, Salah Alghyaline, Jun-Wei Hsieh, Jim Z. C Lai

Journal of Marine Science and Technology–Taiwan

Discovering frequent itemsets is an essential task in association rules mining and it is considered to be computationally expensive. To find the frequent itemsets, the algorithm of frequent pattern growth (FP-growth) is one of the best algorithms for mining frequent patterns. However, many experimental results have shown that building conditional FP-trees during mining data using this FP-growth method will consume most of CPU time. In addition, it requires a lot of space to save the FP-trees. This paper presents a new approach for mining frequent item sets from a transactional database without building the conditional FP-trees. Thus, lots of computing …

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The Study On The Non-Linear Dynamic Causal Relationships Between Construction Index And Its Materials Indexes, Yih-Chang Wang, Ran Huang, Chien-Chung Nieh, Tsai-Lung Weng Apr 2016

The Study On The Non-Linear Dynamic Causal Relationships Between Construction Index And Its Materials Indexes, Yih-Chang Wang, Ran Huang, Chien-Chung Nieh, Tsai-Lung Weng

Journal of Marine Science and Technology–Taiwan

This paper aims to examine the short-run and long-run nonlinear dynamic relationship between indexes of construction and cement or steel in the Taiwan stock markets over the 1995- 2011 periods. In addition to traditional linear co-integration tests, the threshold co-integration and asymmetric threshold error-corrrection models (TECM) suggested by Enders and Siklos (2001) are used. Linear co-integration tests reveal no co-integration between the construction index and either of the cement and steel indexes, while threshold co-integration tests show existence of the co-integration relationship and asymmetric adjustment. Further analysis from TECM Granger causality tests finds evidence of a bi-directional causality between cement …

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