Life Sciences Commons^™

A Meshless Method With Radial Basis Function For Solving Unsaturated Flow In Heterogeneous Porous Media, Cheng-Yu Ku, Chih-Yu Liu, Wei-Po Huang, Jing-En Xiao

Journal of Marine Science and Technology

This paper presents a study for solving unsaturated flow in heterogeneous porous media using the meshless method with the radial basis function (RBF). For modeling the nonlinear hydrological process in unsaturated zone, an exponential model is introduced in the Richards equation such that we may obtain the linearized Richards equation. We adopt the multiquadric function as the RBF in the meshless method for solving the linearized Richards equation. For simulating the unsaturated flow problems in layered heterogeneous soils, the flux and the head must satisfy the continuity condition at the interface. Several examples are carried out for modeling the hydrological …

Dioxins Contamination In Sediment And Their Effect On Accumulation In The Portuguese Oyster (Crassostrea Angulata) And White Shrimp (Litopenaeus Vannamei), Yin-Yu Chen, Yu-Sheng Wu, Hsiang-Yin Chen, Zhen-Hao Liau, Fan-Hua Nan

Journal of Marine Science and Technology

This research aims to realize whether the dioxin accumulation in the oyster and white shrimp which were cultured in the dioxin pollutant sediment. This presented evidence indicated that dioxin was detected in all experimental groups with high concentration accumulated in experiment animals. Observation of the concentration, the PCDD/F, 2,3,7,8-T4CDD was with high concentration in the sediment and declined with the time elapsed. Detection of the dioxin accumulated in the animal, the accumulative maximum amounts was in the oyster as 3746.16 (pg-TEQ/g d.w.) and in the shrimp as 705.44 (pg-TEQ/g d.w.). The detected amount of dioxin in the supernatant was quite …

Catch Rates And Distribution Pattern Of The Silky Shark, Carcharhinus Falciformis, Caught By The Taiwanese Large-Scale Longline Fishery In The Indian Ocean, Chia Yun Li, Xing-Han Wu, Shang Yin Vanson Liu, Sheng-Ping Wang, Wen-Pei Tsai

Journal of Marine Science and Technology

The silky shark, Carcharhinus falciformis, is widely distributed in tropical and temperate waters, and it is a common bycatch species for tuna longline fisheries. This study examined the distribution of and presents relative abundance indices of the silky shark in the Indian Ocean by using logbook and observer data from the Taiwanese large-scale tuna longline fishery between 2005 and 2019. Due to the high zero catch rate, a zero-inflated negative binomial (ZINB) model was used to standardize catch per unit effort. Due to a lack of detailed targeting information, the fishery strategy was identified by using cluster analysis based on …

Accumulation And Bioavailability Of Heavy Metals (Cadmium, Chromium, Nickel, Lead And Zinc) In Water And Sediment Samples In The Musa Creek, Northwest Coasts Of The Persian Gulf, Saghafiankhoo Sedigheh, Battaleb-Looie Sedigheh, Amanipoor Hakimeh, Dravishi Khatooni Javad, Ghanemi Kamal

Journal of Marine Science and Technology

The current study aimed to investigate the total concentrations of heavy metals in water and sediment samples as well as their bioavailability in sediments of Musa Creek. Twenty samples including 10 sediments and 10 water samples were collected from 10 stations. The concentration of heavy metals was measured using inductively coupled plasma–mass spectrometry. The bioavailability of heavy metals was carried out by first step of Tessier sequential extraction method so called single extraction in the manuscript. The results showed that the mean concentrations of cadmium, chromium, nickel, and zinc in water samples was 0.17, 7.44, 43.80, and 8.85 µg/L, respectively. …

Using The Inverse Method To Investigate Flow Models For Mixed Convection Of Annular Finned Tube Heat Exchanger, Han-Taw Chen, Cheng-Hui You, Wei-Lun Hsu, Jiang-Ren Chang

Journal of Marine Science and Technology

The inverse heat conduction method (IHCM) and three-dimensional (3D) computational fluid dynamic (CFD) in combination with are used to select the appropriate flow model and near-wall treatment for the mixed convection of the annular finned tube heat exchanger. Thus, the numerical results obtained by all k-ε models and near-wall treatments are yielded for 4 m/s ≤ Va ≤ 5 m/s. First, IHCM combined with is applied to estimate and Q values. The obtained estimates of and Q are used as reference values for CFD. The results show that the Tk and results obtained by the standard (STD) k-ε model with …

Parametric Analyses Of The Dynamic Response And Fatigue Life Of A Compliant Vertical Access Riser With Internal Flow, Fuheng Li, Haiyan Guo, Xiaomin Li, Zhen Liu, Honglu Gu, Peng Cui

Journal of Marine Science and Technology

Subsea interventions on wellheads can be directly performed from a platform using a compliant vertical access riser (CVAR), thereby incurring tremendous economic benefits. The dynamic response and the fatigue damage of a CVAR subjected to regular waves are important for assessing its application feasibility. Therefore, a reasonable numerical model is presented for assessing the damage to a CVAR considering the internal flow using the slender rod theory. The finite element method combined with a Newmark-β scheme is employed to discretize the equations and update the time integration. The Palmgren-Miner rule is applied for fatigue life prediction, focusing on the wave-induced …

Prediction Of Remaining Useful Life Of Wind Turbine Shaft Bearings Using Machine Learning, Jinsiang Shaw, Bingjie Wu

Journal of Marine Science and Technology

Wind turbines are a major trend in the current green energy market. Wind energy is abundant, and if utilized properly, can result in significant reductions in carbon emissions. Therefore, the development of wind power systems is urgently required. However, wind turbines are mainly built in unmanned areas. Regular inspections require substantial manpower and material resources, and doubts regarding the accuracy of the inspected data may occur. Therefore, it is necessary to establish an automatic diagnostic method for determining the remaining useful life (RUL) of a wind turbine to facilitate predictive maintenance. In this study, a multi-class support vector machine (SVM) …

Supply Chain Management For Superyacht Construction In Taiwan, Chun Pong Wong

Journal of Marine Science and Technology

In the last 20 years, Taiwan’s superyacht construction industry has performed well in the global market; however, numerous yacht builders still practice traditional supply chain management (SCM), which is often inefficient and regularly leads to time and cost overruns. This study aimed to answer two research questions: 1) what SCM challenges does the superyacht construction industry face? and 2) what SCM strategies and practices should be adopted to improve the efficacy and profitability of superyacht construction companies?

Numerous studies have explored supply chains (SCs) and SCM, but few have focused on the superyacht construction industry. Superyacht construction projects are highly …

The Impact Of Variable Curing Conditions On The Properties And Microstructures Of Mixtures Of Ground Granulated Blast Furnace Slag And Circulating Q1 Fluidized Bed Combustion Ash, Shao-Heng Hsieh, Wei-Chung Yeih, Ran Huang

Journal of Marine Science and Technology

The use of Portland cement, an important construction material, is encountering growing challenges because of its adverse environmental impacts. In this study, a new hydration system without Portland cement, which blends ground granulated blast furnace slag (GGBFS) and circulating fluidized bed combustion (CFBC) ash, was developed and tested. The variables included the effect of different types of CFBC ash, the mass ratios between CFBC ash and GGBFS, and different curing temperatures. The mortar properties were determined through the compressive strength test, absorption test, shrinkage test, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The main results were as follows: …

A Marine Gis-Based Alert System To Prevent Vessels Collision With Offshore Platforms, Sheng-Long Kao, Ki-Yin Chang, Tai-Wen Hsu

Journal of Marine Science and Technology

How to effectively use an intelligent aid-to-navigation (AtoN) to prevent ships from accidentally colliding with offshore marine platforms (OMPs) is an important issue for maritime environment. This study proposes a novel collision alert system with three components to process Automatic Identification System (AIS) data in the cloud and broadcast AtoNs to ships in order to avoid collision with OMPs. The first component receives as input fuzzy linguistic variables (vessel size, relative speed, and approach distance) from the AIS data and calculates the radius of the guarding ring. The second component serves a Marine GIS (MGIS), where the system simulates the …

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

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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 …

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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

Journal of Marine Science and Technology

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 …