Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1231 - 1260 of 5926

Full-Text Articles in Mechanical Engineering

Effectiveness Against White Sharks Of The Rpela Personal Shark Deterrent Device Designed For Surfers, Craig Blount, Dan Pygas, Marcus P. Lincoln Smith, Daryl P. Mcphee, Colby Bignell, Ocean Ramsey Sep 2021

Effectiveness Against White Sharks Of The Rpela Personal Shark Deterrent Device Designed For Surfers, Craig Blount, Dan Pygas, Marcus P. Lincoln Smith, Daryl P. Mcphee, Colby Bignell, Ocean Ramsey

Journal of Marine Science and Technology–Taiwan

Many shark bites to humans, including fatalities, have involved surfers. Various personal shark deterrents are commercially available to surfers, including Rpela v2, which is a battery-powered device fitted to a surfboard. It produces an electric field around the surfer aimed at deterring sharks from approaching or biting by disrupting their electro-reception organs. The device was tested on white sharks (Carcharodon carcharias) at Salisbury Island, Western Australia. In total, 46 trials were done with the Rpela v2 either active or not active to determine the device’s effect on sharks’ response to a floating board with fish bait attached (to tempt a …


Inter-Annual Changes Of Water Temperature In The Southern South China Sea's Continental Shelf: The Influence Of Enso On Malaysian Waters, Afifi Johari, Mohd Fadzil Akhir, Muhammad Naim Satar, Zuraini Zainol, Guo Jingsong Sep 2021

Inter-Annual Changes Of Water Temperature In The Southern South China Sea's Continental Shelf: The Influence Of Enso On Malaysian Waters, Afifi Johari, Mohd Fadzil Akhir, Muhammad Naim Satar, Zuraini Zainol, Guo Jingsong

Journal of Marine Science and Technology–Taiwan

An extensive amount of data from the World Ocean Database (WOD) that covers the southern South China Sea (SSCS) were analysed to study the long-term trends and variations of the El-Nino Southern Oscillation (ENSO) event. The WOD data were selected from 1951 to 2010, which included the area within 0–10 °N and 100–117 °E. El-Nino and La-Nina anomaly results showed that the sea surface temperature anomalies (SSTa) trend of SSCS was higher during offset-El-Nino years and lower during offset-La-Nina years. Besides, the inter-annual vertical water temperature profile revealed that the deepening of the warmer water temperature occurred in February and …


The Eumedonine Genera Eumedonus H. Milne Edwards, 1834, And Gonatonotus White, 1847 (Crustacea: Brachyura: Pilumnidae) In Taiwan, Peter K. L Ng, Chia-Wei Lin Sep 2021

The Eumedonine Genera Eumedonus H. Milne Edwards, 1834, And Gonatonotus White, 1847 (Crustacea: Brachyura: Pilumnidae) In Taiwan, Peter K. L Ng, Chia-Wei Lin

Journal of Marine Science and Technology–Taiwan

Two species of eumedonine crabs, Eumedonus zebra Alcock, 1895, and Gonatonotus nasutus Chia & Ng, 2000, are recorded from Taiwan, the former for the first time. Both are also new genera records for the island. Notes on variation are noted and their taxonomy briefly treated. The number of eumedonine species, all of which are obligate symbionts on echinoderms, known from the island is now seven genera and seven species.


An Analysis Of Consumer Evaluations Of The “Tagonoura Shirasu” Certification Under The Japan Geographical Indication Protection System, Yu-Heng Lu, Takahiro Sajiki Sep 2021

An Analysis Of Consumer Evaluations Of The “Tagonoura Shirasu” Certification Under The Japan Geographical Indication Protection System, Yu-Heng Lu, Takahiro Sajiki

Journal of Marine Science and Technology–Taiwan

Over time, the Geographical Indication (GI) protection system has been independently adopted in more than 100 countries worldwide. In Japan, the GI protection system has been operating since 2015 in response to a growing interest in local brands. Therefore, based on a questionnaire survey, we econometrically analyze the consumer evaluation of Shizuoka Prefecture’s Shirasu “Tagonoura Shirasu,” which is registered under the GI protection system. Shirasu is a collective term for long and narrow larvae such as anchovy (Engraulis japonicus), sardine (Sardinops melanostictus), or red-eye round herring (Etrumeus sadina). Based on the contingent valuation method, we clarified that consumers' additional willingness …


A Two-Stage Approach To Integrate Vessel Geo-Tracking Data And Logbooks For Monitoring Fishing Activity Of Coastal Fisheries In Waters Off Northwestern Taiwan, Yi-Jou Lee, Nan-Jay Su, Cheng-Hsin Liao, Wei-Chuan Chiang, Chun-Huei Li Sep 2021

A Two-Stage Approach To Integrate Vessel Geo-Tracking Data And Logbooks For Monitoring Fishing Activity Of Coastal Fisheries In Waters Off Northwestern Taiwan, Yi-Jou Lee, Nan-Jay Su, Cheng-Hsin Liao, Wei-Chuan Chiang, Chun-Huei Li

Journal of Marine Science and Technology–Taiwan

Catch and fishing effort data are fundamental information to stock assessment and fisheries management, but difficult to obtain without the support of administration and sound fishery data collection system. This study integrated various sources of data from a simplified vessel geo-tracking system and logbooks from interviews with captains of coastal gillnet fisheries. We developed a two-step approach based on hierarchical cluster analysis to characterize the operation patterns and infer the fishing activities of the fishery. Results showed that the fishing effort in terms of operation duration could be estimated precisely for various vessel sizes, with catch composition and harvest information …


Effect Of Chlorine Dioxide On The Removal Of Sulfadimethoxine And Sulfamethoxazole In Freshwater And Seawater, Zhen-Hao Liao, Dai-Chee Ng, Yu-Sheng Wu, Fan Hua Nan Sep 2021

Effect Of Chlorine Dioxide On The Removal Of Sulfadimethoxine And Sulfamethoxazole In Freshwater And Seawater, Zhen-Hao Liao, Dai-Chee Ng, Yu-Sheng Wu, Fan Hua Nan

Journal of Marine Science and Technology–Taiwan

This study aimed to understand the fate of sulfonamides (SAs) under dark condition in a laboratory-scale aquatic system, and evaluate the removal of SAs by using Chlorine dioxide. Based on the mass spectrometry quantification, our results have shown that two sulfonamides were transformed at very slow rate in the dark. The 180 day degradation efficiencies (%) of sulfadimethoxine (SDM) in freshwater and seawater were 6.37 ± 2.56 and 4.38 ± 3.43, respectively, while those of sulfamethoxazole (SMX) in freshwater and seawater were 7.81 ± 2.15 and 6.60 ± 2.69, respectively. In the treatment of Chlorine dioxide for the removal of …


Long-Term Observations Of Interannual And Decadal Variation Of Sea Surface Temperature In The Taiwan Strait, Ming-An Lee, Wei-Po Huang, Yi-Lo Shen, Jinn-Shing Weng, Bambang Semedi, Yi-Chen Wang, Jui-Wen Chan Sep 2021

Long-Term Observations Of Interannual And Decadal Variation Of Sea Surface Temperature In The Taiwan Strait, Ming-An Lee, Wei-Po Huang, Yi-Lo Shen, Jinn-Shing Weng, Bambang Semedi, Yi-Chen Wang, Jui-Wen Chan

Journal of Marine Science and Technology–Taiwan

Long-term observations of interannual and decadal variation of sea surface temperature (SST) in the Taiwan Strait (TS) were studied for the period 1870–2018; the climatology data were obtained from the Met Office Hadley Centre, UK. In the study period, the highest annual mean and lowest SST observed were 25.3°C in 1998 and 22.4°C in 1919, respectively. Six distinct regimes were identified. The first regime of fairly stable or slightly cooling SST lasted through the 1920s. The two regime shifts of 1919 to 1945 and 1976–1977 to 1998 led to the two fast warming trends of 2.0°C in 26 years, from …


Experimental Investigation And Modeling Of The Response Surface Methodology For The Optimization Of A Multiloop Heat Pipe, Dar-Sun Liou Sep 2021

Experimental Investigation And Modeling Of The Response Surface Methodology For The Optimization Of A Multiloop Heat Pipe, Dar-Sun Liou

Journal of Marine Science and Technology–Taiwan

Considering thermohydrodynamic instabilities in the design of cooling systems has become a trend, which has led to the evolution of thermal management. However, such instabilities, which cause flow perturbations, are difficult to explain by using physical theories. The aim of this study was to use a parameter-based modeling technique, namely the response surface methodology (RSM), to characterize the dynamics of multiloop heat pipes (MLHPs) under various heat loads. The RSM, which is based on statistics, was used to determine the relationship between the design parameters and thermal responses of MLHPs, which are represented using polynomials. Th aim of our RSM …


Supply Chain Inventory Model With Markov Chain Demand, Zhi-Ping Lin, Su-Ping Ho Sep 2021

Supply Chain Inventory Model With Markov Chain Demand, Zhi-Ping Lin, Su-Ping Ho

Journal of Marine Science and Technology–Taiwan

This study aims to develop a new one-vendor multiple-buyers integrated inventory model. We believe that our proposed model can forecast the demand of all buyers in the coming future by using data that have already existed and to minimize the total cost-for both buyers and vendors. In recent days, the Markov chain approach has played one of the critical methods of demand forecasting in the Supply Chain Management (SCM) field. The proposed model of this study is to analysis the demand of all buyers in one specific season that was impacted by the demand in the same season from last …


Fire Resistance Of Steel Connectors Of Precast Lightweight Concrete Walls, Jen-Hao Chi, Maochieh Chi, Yue-Lin Huang Sep 2021

Fire Resistance Of Steel Connectors Of Precast Lightweight Concrete Walls, Jen-Hao Chi, Maochieh Chi, Yue-Lin Huang

Journal of Marine Science and Technology–Taiwan

In this study the fire test was performed to investigate the mechanic behaviors and failure patterns of precast normal weight concrete (NWC) and lightweight concrete (LWC) walls with three types of commonly used steel connectors, namely dry (61), wet (81), and bearing (56E) connectors. For the LWC wall specimens, on lateral application of tension, the cracking load values of the dry, wet, and bearing-type connectors were 95.1%, 86.3%, and 83.0%, respectively, of the original loads, and their ultimate load values were 81.6%, 90.7%, and 85.0%, respectively, of the original. In the shearing test after the fire resistance test, the cracking …


Differential Evolution Algorithm For Ship Path Planning In Open Waters, Yu-Tao Kang, Wei-Jiong Chen, Jin-Hui Wang Sep 2021

Differential Evolution Algorithm For Ship Path Planning In Open Waters, Yu-Tao Kang, Wei-Jiong Chen, Jin-Hui Wang

Journal of Marine Science and Technology–Taiwan

A general approach to the derivation of simple yet accurate formulas for identifying bandpass nonlinear channels in or-thogonal frequency-division multiplexing (OFDM) systems is proposed in this paper. The OFDM is an widely adopted tech-nique for wideband communication applications. An OFDM signal could be highly vulnerable to nonlinearities in a com-munication link. This makes proper estimation of the nonlin-ear channel essential for an OFDM system. A nonlinear bandpass communication channel is commonly described by a complex Voletrra series, in which the task of nonlinear channel identification is to determine the Volterra kernels. This task can become very difficult when the order …


Integrated Simulation Of Virtual Prototypes And Control Algorithms Of Unmanned Surface Vehicles Based On A Robot Operating System, Hye-Won Lee, Joo-Hyun Woo, Myung-Il Roh, Seung-Ho Ham, Luman Zhao, Sol Ha, Nak-Wan Kim, Chan-Woo Yu Sep 2021

Integrated Simulation Of Virtual Prototypes And Control Algorithms Of Unmanned Surface Vehicles Based On A Robot Operating System, Hye-Won Lee, Joo-Hyun Woo, Myung-Il Roh, Seung-Ho Ham, Luman Zhao, Sol Ha, Nak-Wan Kim, Chan-Woo Yu

Journal of Marine Science and Technology–Taiwan

Unmanned surface vehicles (USVs) require autonomous software with a high level of liberalization and automation to complete various missions. Therefore, experimental verification and validation of this software at the initial design stage are essential. However, such experiments are impossible before the actual hardware is developed, and the creation of an external environment for the mission requires substantial cost and time. In this study, virtual prototypes of the mission environment and hardware for the USV are developed. Then, a simulation environment for testing the control algorithms in the autonomous software is constructed. Data communication with the USV hardware is necessary for …


Identification Of Nonlinear Channels In Bandpass Communication Systems With Ofdm Inputs, Jen-Ho Cheng, Ching-Hsiang Tseng Sep 2021

Identification Of Nonlinear Channels In Bandpass Communication Systems With Ofdm Inputs, Jen-Ho Cheng, Ching-Hsiang Tseng

Journal of Marine Science and Technology–Taiwan

A general approach to the derivation of simple yet accurate formulas for identifying bandpass nonlinear channels in or-thogonal frequency-division multiplexing (OFDM) systems is proposed in this paper. The OFDM is an widely adopted tech-nique for wideband communication applications. An OFDM signal could be highly vulnerable to nonlinearities in a com-munication link. This makes proper estimation of the nonlin-ear channel essential for an OFDM system. A nonlinear bandpass communication channel is commonly described by a complex Voletrra series, in which the task of nonlinear channel identification is to determine the Volterra kernels. This task can become very difficult when the order …


Molecular Interfaces And Heterogeneous Bubble Nucleation From Heated Surfaces At Nanoscale, Manish Gupta Aug 2021

Molecular Interfaces And Heterogeneous Bubble Nucleation From Heated Surfaces At Nanoscale, Manish Gupta

Dissertations - ALL

Heat transfer from a solid surface to fluid occurs in numerous applications, such as boilers, refrigerators, power electronics, etc., and include various underlying phenomena of thin-film evaporation, boiling, condensation, surface wetting, and droplet evaporation. Several studies show that heat transfer can be enhanced significantly by incorporating micro and nanoscale features onto surfaces. Phase change heat transfer plays an important role in dissipating energy from hot surfaces and distributing it to bulk liquid due to high latent heat of liquids. Boiling, a phase change heat transfer phenomenon, happens when the surface is heated to a temperature above the saturation temperature of …


Creation Of A Cip Method For The Heat Exchangers At Rolls-Royce, Melanie Howe, Austin Williams, Caroline Dempsey, Bethany Fralick Aug 2021

Creation Of A Cip Method For The Heat Exchangers At Rolls-Royce, Melanie Howe, Austin Williams, Caroline Dempsey, Bethany Fralick

Journal of the South Carolina Academy of Science

Rolls-Royce produces various engines which must be tested prior to their distribution to ensure a high-quality product. The manufacturing plant contains four test cells where the engines can be subjected to high levels of torque and extreme temperatures. A heat exchanger is necessary in this testing system and over time, unwanted waste accumulates on the system’s plates. The team is tasked with developing and implementing a system mounted on a mobile cart which can provide data to determine whether the plates need to be cleaned. For this cleaning system to work, it must fully saturate the heat exchanger in cleaning …


The Effect Of Noise-Reducing Acoustic Panels On The Noise Levels And Overall Safety Of Infant Sleep Machines, Pranav Poola Aug 2021

The Effect Of Noise-Reducing Acoustic Panels On The Noise Levels And Overall Safety Of Infant Sleep Machines, Pranav Poola

Journal of the South Carolina Academy of Science

Infant sleep machines (ISMs) are devices used to help infants fall asleep faster and stay asleep for longer amounts of time, yet they can often be too loud for infantile ears, which could potentially be dangerous. This research aimed to minimize the risks of infant sleep machines without reducing the effectiveness of the infant sleep machines themselves through the use of acoustic panels. Based on previous studies, it was hypothesized that the acoustic panels would reduce the noise levels of the ISM to less than recommended limits of 50 dB-A. A specific corner of a designated room was prepared with …


Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen Aug 2021

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …


Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen Aug 2021

Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen

Journal of Sustainable Mining

In axial ventilation fans, the generation of a uniform flow velocity is desirable for better efficiency. To that end, different fan blade types have been developed to achieve better flow uniformity. This article aimed to characterize the flow distribution and its uniformity in four blade designs, namely constant chord, tapered blade, skewed blade, and tapered skewed blade, using Computational Fluid Dynamics (CFD). The study employs an iterative study where key study decisions are made as the study progresses. The study began with the selection of a blade profile for the study. A comparative study between the NACA seven-digit and four-digit …


Socio-Technical Perspective For Electronic Tax Information System In Tanzania, Lucas Ngowi, Ellen Kalinga Jul 2021

Socio-Technical Perspective For Electronic Tax Information System In Tanzania, Lucas Ngowi, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Socio-technical systems theory has rarely been used by system architects in setting up computing systems. However, the role of socio-technical concepts in computing, which is becoming social in nature, has made the concepts more relevant and commercial. Tax information systems are examples of such systems because they are influenced by external variables such as the political environment, technological trends, and social environment, introducing complexity in their deployment and determining the type of e-services and their delivery to a diverse group of people. It was observed that in Tanzania there is resistance, reluctance and minimal use of electronic tax system because …


Fully Coupled Internal Radiative Heat Transfer For The 3d Material Response Of Heat Shield, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin Jul 2021

Fully Coupled Internal Radiative Heat Transfer For The 3d Material Response Of Heat Shield, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

The radiative transfer equation (RTE) is strongly coupled to the material response code KATS. A P-1 approximation model of RTE is used to account for radiation heat transfer within the material. First, the verification of the RTE model is performed by comparing the numerical and analytical solutions. Next, the coupling scheme is validated by comparing the temperature profiles of pure conduction and conduction coupled with radiative emission. The validation study is conducted on Marschall et al. cases (radiant heating, arc-jet heating, and space shuttle entry), 3D Block, 2D IsoQ sample, and Stardust Return Capsule. The validation results agree well for …


Lagrangian And Eulerian Accelerations In Turbulent Stratified Shear Flows, Frank G. Jacobitz, Kai Schneider Jul 2021

Lagrangian And Eulerian Accelerations In Turbulent Stratified Shear Flows, Frank G. Jacobitz, Kai Schneider

School of Engineering: Faculty Scholarship

The Lagrangian and Eulerian acceleration properties of fluid particles in homogeneous turbulence with uniform shear and uniform stable stratification are studied using direct numerical simulations. The Richardson number is varied from Ri=0, corresponding to unstratified shear flow, to Ri=1, corresponding to strongly stratified shear flow. The probability density functions (pdfs) of both Lagrangian and Eulerian accelerations have a stretched-exponential shape and they show a strong and similar influence on the Richardson number. The extreme values of the Eulerian acceleration are stronger than those observed for the Lagrangian acceleration. Geometrical statistics explain that the magnitude of the Eulerian acceleration is larger …


An Economical Method For Securely Disintegrating Solid-State Drives Using Blenders, Brandon J. Hopkins Phd, Kevin A. Riggle Jul 2021

An Economical Method For Securely Disintegrating Solid-State Drives Using Blenders, Brandon J. Hopkins Phd, Kevin A. Riggle

Journal of Digital Forensics, Security and Law

Pulverizing solid-state drives (SSDs) down to particles no larger than 2 mm is required by the United States National Security Agency (NSA) to ensure the highest level of data security, but commercial disintegrators that achieve this standard are large, heavy, costly, and often difficult to access globally. Here, we present a portable, inexpensive, and accessible method of pulverizing SSDs using a household blender and other readily available materials. We verify this approach by pulverizing SSDs with a variety of household blenders for fixed periods of time and sieve the resulting powder to ensure appropriate particle size. Among the 6 household …


Liner Sailing Speed Optimization Considering Wind And Waves, Zhaokun Wei, Xinlian Xie, Tiantian Bao Jul 2021

Liner Sailing Speed Optimization Considering Wind And Waves, Zhaokun Wei, Xinlian Xie, Tiantian Bao

Journal of Marine Science and Technology–Taiwan

This paper proposes a new sailing speed optimization problem considering sea conditions such as wind and waves for a container shipping company. Since wind and waves, as exterior factors, can reduce speed, more power is employed as compensation to maintain regular service frequency and avoid delay, resulting in additional bunker consumption and higher cost. Hence, it is necessary to optimize the sailing speed according to the wind and waves. A power model was built to determine the reduced speed caused by the wind and waves for quantifying the speed reduction. On the basis of the proposed model, we developed a …


A Bilevel Mathematical Approach For The Empty Container Repositioning Proble With A Sharing And Exchanging Strategy In Liner Shipping, Dung-Ying Lin, Chieh-Ju Juan Jul 2021

A Bilevel Mathematical Approach For The Empty Container Repositioning Proble With A Sharing And Exchanging Strategy In Liner Shipping, Dung-Ying Lin, Chieh-Ju Juan

Journal of Marine Science and Technology–Taiwan

In the maritime industry, the management of empty containers is a significant issue whose costs account for a large proportion of the total world fleet running costs. To reduce repositioning activities and increase cost effectiveness, this paper proposes a solution framework considering empty container sharing and exchanging strategies to coordinate the shipping lines in a maritime transportation network. The proposed solution framework considers an empty container matching platform company and a group of shipping lines in a given shipping network. Because of the interactive relationship between the two parties, the proposed problem is formulated as a bilevel programming problem, and …


Investigating Model Solution Correctness For Parameter Uncertainty In Both Objective Function And Constraints, Shangyao Yan, Sin-Siang Wang, Chun-Yi Wang Jul 2021

Investigating Model Solution Correctness For Parameter Uncertainty In Both Objective Function And Constraints, Shangyao Yan, Sin-Siang Wang, Chun-Yi Wang

Journal of Marine Science and Technology–Taiwan

To resolve engineering management problems encountered in the real world, optimization models are usually formulated with some parameter assumptions. Parameter uncertainty, which may arise due to changes in the environment or human error, may thus be incorporated into the objective function and the constraints. However, to simplify the modeling, the values of these parameters are usually set or projected as deterministic values. It is no wonder that the modelling results based on these inaccurate parameters are neither correct nor reliable. Thus, it is important to examine the correctness of the model results in relation to parameter uncertainty. This study aims …


Modular Design And Implementation Of An Automatic Power Factor Regulator For Energy Savings On Fishing Vessels, Chien-Hsing Lee, Shih-Hsien Hsu, Joe-Air Jiang Jul 2021

Modular Design And Implementation Of An Automatic Power Factor Regulator For Energy Savings On Fishing Vessels, Chien-Hsing Lee, Shih-Hsien Hsu, Joe-Air Jiang

Journal of Marine Science and Technology–Taiwan

This study describes the experiences of modular design and implementation of an automatic power factor regulator for improving energy efficiency on Taiwanese longline fishing vessels. The load capacities of such vessels are typically divided into three categories, depending on the gross tonnage or fish carrying capacity: less than 100 kW, from 100 kW to less than 250 kW, and larger than 250 kW. For attaining proper power factor improvement, a compensation unit with a total of 30 kVar, 60 kVar and 90 kVar was sized and assembled with capacitors of 10, 15 and 20 kVar to enable control within 12 …


Key Risk Factors Influencing Harbor Tugboat Operations For Kaohsiung Port, Wen-Jui Tseng, Ji-Feng Ding, Chia-Ming Liu, Liou-Yuan Li Jul 2021

Key Risk Factors Influencing Harbor Tugboat Operations For Kaohsiung Port, Wen-Jui Tseng, Ji-Feng Ding, Chia-Ming Liu, Liou-Yuan Li

Journal of Marine Science and Technology–Taiwan

The harbor tugboat operation is a very important business and process of Kaohsiung port. To ensure the safety of harbor tugboat operations and to reduce the occurrence of accidents, it is an important issue to conduct a risk assessment of tugboat operations for Kaohsiung port. Hence, the main purpose of this paper is employ the analytic hierarchy process (AHP) method to evaluate key risk factors influencing the harbor tugboat operations for Kaohsiung port. At first, a total of three evalu-ation dimensions with 14 preliminary risk factors are gener-ated from literature and interviews of tugboat captains. We then applied the steps …


Free Vibration Analysis Of A Free-Free Single-Tapered Beam Carrying Arbitrary Concentrated Elements Using Modified Mode-Superposition Method (Mmsm), Chia-Chin Wu Jul 2021

Free Vibration Analysis Of A Free-Free Single-Tapered Beam Carrying Arbitrary Concentrated Elements Using Modified Mode-Superposition Method (Mmsm), Chia-Chin Wu

Journal of Marine Science and Technology–Taiwan

The literature contains scant information on the free vibration analyses of the loaded single-tapered beams (STBs) (i.e., STBs carrying concentrated elements (CEs)) Furthermore, even when such studies have been performed, they generally only consider the case of constrained (e.g., free-clamped (F-C)) beams. In other words, the problem of unconstrained (e.g., free-free (F-F)) loaded STBs has not yet to be addressed. Thus, the present study employs the modified mode-superposition method (MMSM) to investigate the free vibration characteristics of the F-F loaded STB carrying arbitrary various CEs. The investigation focuses particularly on the natural frequencies and mode shapes of the rigid-body motions …


Optimum Design Of The Underwater Discharge System Based On Surrogate Modeling, Jisang Ha, Myung-Il Roh, Seung-Ho Ham, Sung-Jun Lee Jul 2021

Optimum Design Of The Underwater Discharge System Based On Surrogate Modeling, Jisang Ha, Myung-Il Roh, Seung-Ho Ham, Sung-Jun Lee

Journal of Marine Science and Technology–Taiwan

Underwater vehicles are equipped with a device for discharging projectiles, called the underwater discharge system. Because these vehicles have limited space, many studies have attempted to reduce the volume of the underwater discharge system while improving its performance. However, owing to the characteristics of the system, the occupied volume and performance conflict with each other. Therefore, minimizing the occupied volume while satisfying the required performance criteria is the most significant requirement in the design stage. To address this, an optimization problem for the underwater discharge system was mathematically formulated and solved using multi-objective genetic algorithms. Additionally, we proposed a method …


An Analysis Of Key Influencing Factors On Island Tourism Revisit Intentions – Evidence From The Matsu Islands, Chun-Chieh Wang, Hsiao-Chuan Liu, Hsuan-Shih Lee, Cheng-Chi Chung Jul 2021

An Analysis Of Key Influencing Factors On Island Tourism Revisit Intentions – Evidence From The Matsu Islands, Chun-Chieh Wang, Hsiao-Chuan Liu, Hsuan-Shih Lee, Cheng-Chi Chung

Journal of Marine Science and Technology–Taiwan

Sightseeing and tourism not only brings economic benefits to the local community but also drive the development of related industries. In 1992, when the Matsu’s battlefield mission was dissolved, tourism became one of the key development strategies to boom the region. Although the number of visitors to Matsu Islands has risen significantly in recent years, how to increase the island’s willingness to revisit the island has been an important issue. Since local tourism has its own characteristics, island tourism marketing strategies should be different. Many previous studies have quantified the relationship between tourism area satisfaction and willingness to revisit, but …