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Full-Text Articles in Physical Sciences and Mathematics

Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria, Wen-Cheng Lin, Hsin-Hung Cheng Jul 2021

Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria, Wen-Cheng Lin, Hsin-Hung Cheng

Journal of Marine Science and Technology

This study aims to improve maritime safety by enhancing administrative management based on human factors. This study used Fuzzy analytic hierarchy process to analyze the risks and threats regarding safety maritime criteria. Establishing administrative reform is given the highest priority. First, the current model for crew training system is explored. Second, the marine surveyor is examined to determine if it is professional enough for inspection work. Third, the investigation system used by maritime safety investigators should be inspected. The suggestions mentioned expect to establish a maritime administrative reform that could pave the way for the application of maritime safety around …


Experimental Study On Treatment Of Ballast Water By Inert Flue Gas Deoxidation, Guozhi Bao, Peng Yang, Rui Da, Junxia Li, Guanghui Zhao, Ning Chen Jul 2021

Experimental Study On Treatment Of Ballast Water By Inert Flue Gas Deoxidation, Guozhi Bao, Peng Yang, Rui Da, Junxia Li, Guanghui Zhao, Ning Chen

Journal of Marine Science and Technology

In this paper, the antimicrobial effect of inert flue gas on indicator microorganisms in ballast water was investigated based on a 265h test. The inert flue gas consists of nitrogen (N2) and carbon dioxide (CO2) the microorganisms include Chlorella and Escherichia coli. Within the scope of the test, the killing effect of the microbes treated by combining N2 and CO2 was higher than that of using only either N2 or CO2. When the dissolved oxygen concentration in the ballast water was 0.5 mg/L and the pH value was 6, the killing effect was the highest. At this time, the mortality …


Splitting The Scatter: Distinguishing Marine Organisms From Oceanographic Structures Using Acoustic Monitoring, Zhen Lu, Daisuke Hasegawa, Takahiro Tanaka, David M. Spencer, Yuji Okazaki, Takeshi Okunishi Jun 2021

Splitting The Scatter: Distinguishing Marine Organisms From Oceanographic Structures Using Acoustic Monitoring, Zhen Lu, Daisuke Hasegawa, Takahiro Tanaka, David M. Spencer, Yuji Okazaki, Takeshi Okunishi

Journal of Marine Science and Technology

In the northwest Pacific Ocean, off the Sanriku coast of Japan, convergence between the Tsugaru Warm Current (TWC) and the cold Oyashio Current (OC) results in the formation of highly dynamic oceanographic features that promote high biodiversity and generate hotspots for a range of commercially important fisheries. However, their effects on local biodiversity over much smaller spatiotemporal scales ( < 1 km) remains unclear. With the development of acoustic technology in recent years, echo-sounders are increasingly being used to conduct high-precision fishery resource assessments and detect small-scale variability in the oceanic thermohaline structure. In this study, we conducted a simultaneous hydrographic and dual-frequency echo-sounder survey to discriminate oceanographic features and marine organisms in the TWC-OC confluence zone. Echograms of acoustic backscatter measured at 38 kHz detected similar oceanographic features that were obtained from our hydrographic survey observations, but these features were less pronounced in the 120 kHz echograms. The dynamic oceanographic structure in the TWC-OC zone returned a large amount of backscatter, making it difficult to identify marine organisms from the scatter. The frequency differences of volume backscattering strength (SV) were, however, able to distinguish oceanographic structures from zooplankton detections. Outcomes from this study highlight the difficulty of distinguishing between hydrographic and biological detections in dynamic oceanographic environments. Further research into the acoustic frequency characteristics of heterogeneous hydrographic features will help better understand how species distributions are affected, so that the acoustic method can be used to provide more accurate estimates of species abundance.


Fine-Scale Vertical Movements And Behavior Of Immature Skipjack Tuna (Katsuwonus Pelamis) Off Eastern Taiwan, Wei-Chuan Chiang, Takayuki Matsumoto, Shian-Jhong Lin, Qi-Xuan Chang, Michael K. Musyl, Yuan-Shing Ho, Fumio Ohta Jun 2021

Fine-Scale Vertical Movements And Behavior Of Immature Skipjack Tuna (Katsuwonus Pelamis) Off Eastern Taiwan, Wei-Chuan Chiang, Takayuki Matsumoto, Shian-Jhong Lin, Qi-Xuan Chang, Michael K. Musyl, Yuan-Shing Ho, Fumio Ohta

Journal of Marine Science and Technology

Skipjack tuna are globally distributed in tropical and temperate seas but little is known about their fine-scale diving patterns and how fish size and (or) maturity influences patterns off eastern Taiwan. A total of 211 immature skipjack (36 e 47 FL cm) in the study were caught by trolling near subsurface fish aggregating devices (FADs) near Green Island (southeastern Taiwan) and were tagged with Lotek LAT-2910 archival tags. The low rate of recovery (2.4%) suggests a high post-release mortality but this low rate could also be consistent with large population sizes, dispersal, tag loss or uncooperative fishers. Five individuals were …


Evaluating The Fish Aggregation Effect Of Wind Turbine Facilities By Using Scientific Echo Sounder In Nanlong Wind Farm Area, Western Taiwan, Ting-Chieh Huang, Hsueh-Jung Lu, Jia-Rong Lin, Shih-Hsuan Sun, Kou-Wei Yen, Jing-Yi Chen Jun 2021

Evaluating The Fish Aggregation Effect Of Wind Turbine Facilities By Using Scientific Echo Sounder In Nanlong Wind Farm Area, Western Taiwan, Ting-Chieh Huang, Hsueh-Jung Lu, Jia-Rong Lin, Shih-Hsuan Sun, Kou-Wei Yen, Jing-Yi Chen

Journal of Marine Science and Technology

During the stages of construction and operation of the wind power facilities, fishery and fishery resources in the wind farm areas will certainly be changed greatly. One of the major concern is the aggregation effect of wind turbines facility. We use scientific echo sounder together with scuba diving to survey fish aggregations in the wind farm areas. In order to obtain echoes very near the facility, we use tilt beam angle instead of traditional vertical one. Variation of target strength varies while using tilted beam angle were discussed both by ex-situ and in-situ experiment. In ex-situ experiment, we measured TS …


Site Fidelity And Return Trips Of Visually And Olfactorily Inhibited Black Rockfish (Sebastes Schlegelii) Individuals Tracked By Acoustic Telemetry, Mitsuki Kuroda, Yoshinori Tatsu, Yuya Ueda, Hokuto Shirakawa, Kenji Minami, Kazushi Miyashita, Makoto Tomiyasu Jun 2021

Site Fidelity And Return Trips Of Visually And Olfactorily Inhibited Black Rockfish (Sebastes Schlegelii) Individuals Tracked By Acoustic Telemetry, Mitsuki Kuroda, Yoshinori Tatsu, Yuya Ueda, Hokuto Shirakawa, Kenji Minami, Kazushi Miyashita, Makoto Tomiyasu

Journal of Marine Science and Technology

For fish of the genus Sebastes, which have strong site fidelity, understanding the characteristics of their return trips and how their sensory cues influence behavior will be useful for conservation and resource management. Here, we conducted a behavioral tracking study for the black rockfish Sebastes schlegelii using acoustic telemetry and sensory inhibition. We compared aspects of the return process for individuals in a control group (CNT), and fish in blind (BLD) and olfactory inhibition (OLF) conditions. Nine individuals were released 850 m from the fishing site, and all of them returned. However, the time taken to complete the return varied, …


Geospatial And Acoustic Application In An Artificial Reef Site Of South Korea, Myounghee Kang, Rina Fajaryanti, Kyounghoon Lee, Eun-A Yoon, Woo-Seok Oh, Eunbi Min, Young-Jae Shin, Yong-Suk Choi, Byung-Ho Yi, Hui Zhang, Doojin Hwang Jun 2021

Geospatial And Acoustic Application In An Artificial Reef Site Of South Korea, Myounghee Kang, Rina Fajaryanti, Kyounghoon Lee, Eun-A Yoon, Woo-Seok Oh, Eunbi Min, Young-Jae Shin, Yong-Suk Choi, Byung-Ho Yi, Hui Zhang, Doojin Hwang

Journal of Marine Science and Technology

Artificial reefs are important since they provide additional habitat leading to increasing abundance and biomass of marine biota. In a Bukchon artificial reef, Jeju Island, South Korea, environment data, artificial reef properties, and acoustic data in four seasons were integrated to visualize and examine their connections using a geographic information system (GIS). As a result, regarding the spatial and temporal distributions of fishes, January had the lowest Nautical Area Scattering Coefficient (NASC, m2/nm2) and June had the highest NASC, and relatively high NASC was observed from 5 to 30 m deep throughout seasons. The influential circle (effective distance from reef) …


Comparison Of Fish Assemblages Aggregated By Artificial Reefs Using Scuba Diving And Acoustic Surveys, Hsueh-Jung Lu, Jia-Rong Lin, Ting-Chieh Huang, Sunarti Sinaga May 2021

Comparison Of Fish Assemblages Aggregated By Artificial Reefs Using Scuba Diving And Acoustic Surveys, Hsueh-Jung Lu, Jia-Rong Lin, Ting-Chieh Huang, Sunarti Sinaga

Journal of Marine Science and Technology

To determine the aggregation effect of artificial reefs (ARs), we conducted surveys in 16 artificial reefs in Taiwan by using the scientific echo sounder, Simrad EY-60 (200 KHz), along with sighting by scuba divers. Scuba diving was conducted within the reef structures (r ¼ 20 m), whereas acoustic surveys were conducted over a wider range (r ¼ 100 m), with five repeating transects over the ARs. We compared the results obtained from the two methods among 16 artificial reefs in the coastal waters of Taiwan to determine the consistency of the quantitative information between the two methods and to investigate …


Study On The Behavior Of Peled (Coregonus Peled ) Around A Set Net By Ultrasonic Biotelemetry System In A Plateau Lake, China, Jing Liu, Keiichi Uchida, Leiming Yin, Yong Tang, Yoshinori Miyamoto, Binbin Xing May 2021

Study On The Behavior Of Peled (Coregonus Peled ) Around A Set Net By Ultrasonic Biotelemetry System In A Plateau Lake, China, Jing Liu, Keiichi Uchida, Leiming Yin, Yong Tang, Yoshinori Miyamoto, Binbin Xing

Journal of Marine Science and Technology

Sayram Lake is a plateau cold-water lake located in northwestern China. Peled (Coregonus peled ) was introduced to Sayram Lake from Russia in 1998. The behavior characteristics of peled in Sayram Lake are important for fishery resource proliferation, effective fishing, and sustainable development. In this study, we used an ultrasonic biotelemetry system to track the fish around a large-scale set net in Sayram Lake. The purpose of this study is to study the behavior characteristics of the peled and to provide suggestions for the improvement of the set net. The results showed that the fish released in the playground of …


Seasonal Dynamics In Fish Distribution And Abundance Revealed By An Acoustic Survey In Coastal Waters Of The Suzu Area, Kochi Prefecture, Japan, Yanhui Zhu, Kenji Minami, Yuka Iwahara, Kentaro Oda, Koichi Hidaka, Osamu Hoson, Koji Morishita, Sentaro Tsuru, Masahito Hirota, Hokuto Shirakawa, Kazushi Miyashita May 2021

Seasonal Dynamics In Fish Distribution And Abundance Revealed By An Acoustic Survey In Coastal Waters Of The Suzu Area, Kochi Prefecture, Japan, Yanhui Zhu, Kenji Minami, Yuka Iwahara, Kentaro Oda, Koichi Hidaka, Osamu Hoson, Koji Morishita, Sentaro Tsuru, Masahito Hirota, Hokuto Shirakawa, Kazushi Miyashita

Journal of Marine Science and Technology

For Japan's fishery, it is essential to conduct sustainable and efficient fishery owing to the decline in fish catch as well as the fisher population. To obtain information that contributes to sustainable and efficient fishery, we researched appropriate set-net locations with regard to fish distribution, abundance, and environmental characteristics. We conducted surveys from 2017/5 to 2018/2 in the Suzu coastal area, Kochi Prefecture, where the only main industry is set-net fishery. We investigated the seasonal relationships between fish school characteristics, including distribution and size, and marine environmental conditions in the Suzu coastal area, using a quantitative echo sounder (KSE300 SONIC, …


Development Of A Biomass Assessment Method Using Fisheries Echo Sounder For Monitoring Whitebait Fishery In Shizuoka Prefecture, Japan, Kenichi Kobayashi, Yanhui Zhu, Daichi Oshiyama, Kenji Minami, Hokuto Shirakawa, Kazushi Miyashita May 2021

Development Of A Biomass Assessment Method Using Fisheries Echo Sounder For Monitoring Whitebait Fishery In Shizuoka Prefecture, Japan, Kenichi Kobayashi, Yanhui Zhu, Daichi Oshiyama, Kenji Minami, Hokuto Shirakawa, Kazushi Miyashita

Journal of Marine Science and Technology

Coastal fisheries constitute the second most important sector in fishery production in Japan, following offshore fisheries. Thus, spatial evaluation of coastal fishing grounds and understanding of the changes in biomass are important for the sustainable use of fishing resources. For the assessment of spatial fish biomass, a quantitative echo sounder is used, but such a device is not mass produced and involves a high cost. In the present study, we examined the feasibility of biomass assessment using typical commercial fisheries echo sounders that are widely used and cheaper than quantitative echo sounders. Therefore, we aimed to verify the validity of …


Acoustic Survey For Estimating Density Of Anchovy Schools In The South Sea Of Korea, Eunbi Min, Eun-A Yoon, Sung-Tae Kim, Seong Yong Moon, Hyun Woo Kim, Shelly Salim, Taejong Kang, Doo-Jin Hwang May 2021

Acoustic Survey For Estimating Density Of Anchovy Schools In The South Sea Of Korea, Eunbi Min, Eun-A Yoon, Sung-Tae Kim, Seong Yong Moon, Hyun Woo Kim, Shelly Salim, Taejong Kang, Doo-Jin Hwang

Journal of Marine Science and Technology

No abstract provided.


Estimating The Sampling Efficiencies Of A Framed Midwater Trawl And Ring Net For Zooplankton Using An Acoustic Method, Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida May 2021

Estimating The Sampling Efficiencies Of A Framed Midwater Trawl And Ring Net For Zooplankton Using An Acoustic Method, Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida

Journal of Marine Science and Technology

It is well known that there is bias using different sampling gear, such as a framed midwater trawl (FMT) and a ring net, when measuring the density and length distribution of target species. This limit is characterized by the sampling efficiency of the gear. Acoustic monitoring can be used to determine the sampling efficiencies of this gear, as its noninvasive, wide-range sweeps provide more reliable estimates of absolute abundance of the target species. The density measured by the gear can then be standardized by multiplying the initial density measurement by the derived sampling efficiency. In this study, we compared the …


In Situ Broadband Acoustic Measurements Of Age-0 Walleye Pollock And Pointhead Flounder In Funka Bay, Hokkaido, Japan, Kohei Hasegawa, Naizheng Yan, Tohru Mukai May 2021

In Situ Broadband Acoustic Measurements Of Age-0 Walleye Pollock And Pointhead Flounder In Funka Bay, Hokkaido, Japan, Kohei Hasegawa, Naizheng Yan, Tohru Mukai

Journal of Marine Science and Technology

Measurements of the broadband acoustic backscattering from fish should improve acoustic discrimination between species. The pulse compression processing of broadband systems can be used to measure acoustic backscattering with high range resolution and improve signal-to-noise ratio. This may increase opportunities for in situ target strength (TS) measurements, the preferred method of collecting TS data. To evaluate the availability of TS spectra for acoustic discrimination, three Simrad EK80 wideband transceivers and split-beam transducers of 70, 120, and 200 kHz were used to collect in situ frequency responses of TS from age-0 juvenile walleye pollock and pointhead flounder, a swimbladderless flat-fish, distributed …


Volume Scattering And Echo Integration In Fisheries Acoustics Revisited, Masahiko Furusawa May 2021

Volume Scattering And Echo Integration In Fisheries Acoustics Revisited, Masahiko Furusawa

Journal of Marine Science and Technology

Echo integration is the most important method in fisheries acoustics. The basis of the method is volume scattering theory, and the theory assumes that many fish are randomly and homogeneously distributed broader than a beam spread. In actual acoustic surveys, however, we encounter various distributions for which these assumptions do not hold. It is the echo integration method that hypothetically fulfills these assumptions. In this paper, we review the volume scattering theory and the echo integration method historically and theoretically and confirm their bases. We then point out some misunderstandings affected by historical constraints such as the persistence of time …


Thermoelectric Generation And Thermophysical Properties Of Metal Oxide Nanofluids, Xinran Hou, Rong-Tsu Wang, Shaowen Huang, Jung-Chang Wang Mar 2021

Thermoelectric Generation And Thermophysical Properties Of Metal Oxide Nanofluids, Xinran Hou, Rong-Tsu Wang, Shaowen Huang, Jung-Chang Wang

Journal of Marine Science and Technology

This study describes the comprehensive characterization of the diverse water-based nanofluids involving aluminum oxide, titanium dioxide, and zinc oxide nanoparticles, which were prepared through the two-step synthesis method assisted by a microemulsion ultrasound skill with effects of both weight-percent concentration (wt.%) in the range of 1.0% and 5.0% and between 20 oC and 40 0C. The mean cluster size, zeta potential, pH value, viscosity, thermal conductivity, absorbance, light absorption, and electrical charge density of the various nanofluids were surveyed by relative experiments. The results showed that the 2 wt.% Al2O3, 2 wt.% TiO2 …


Wireless Sensor Network-Based Monitoring Of Bridge Pile Foundations For Detecting Scouring Depth, Han-Tang Huang, H. Ping Tserng, Ruei-Yu Hou, Mirosław Skibniewski Mar 2021

Wireless Sensor Network-Based Monitoring Of Bridge Pile Foundations For Detecting Scouring Depth, Han-Tang Huang, H. Ping Tserng, Ruei-Yu Hou, Mirosław Skibniewski

Journal of Marine Science and Technology

Climate change brings about unprecedented increases in the occurrence of storms and flooding. In response to increased risk of bridge pier scouring, there is a need for increased safety monitoring of bridges. This paper presents a wireless sensor network (WSN) - based solution developed to measure micro-vibrations of a bridge pier. Test measurement values are converted with the use of the Fast Fourier Transform (FFT) method to obtain natural frequencies. Scouring depth of the pier is estimated with the use of a Finite Element Method model. WSN is used to collect the signal and to test data transmission stability in …


A New Fuzzy Dea Model For Solving The Mcdm Problems In Supplier Selection, Chi-Mao Tsai, Hsuan-Shih Lee, Guo-Ya Gan Mar 2021

A New Fuzzy Dea Model For Solving The Mcdm Problems In Supplier Selection, Chi-Mao Tsai, Hsuan-Shih Lee, Guo-Ya Gan

Journal of Marine Science and Technology

Supplier selection is a crucial task in supply chain management, and good supply chain management is essential to a company's ability to develop sustainably and gain the trust and satisfaction of its customers. In modern supply chain management, supplier selection often takes the form of a multi-criteria decision-making (MCDM) problem. Thus, to solve this problem, this study formulated a novel fuzzy MCDM model, which is based on the fuzzy data envelopment analysis model. This novel approach can transform the linguistic variables of assessment criteria into well-founded quantitative data for calculation. Moreover, our approach can effectively discriminate between decision-making units (both …


Evaluation Of The Human Discomfort Caused By Ship Vibrations, Laurentiu Picu, Eugen Rusu Mar 2021

Evaluation Of The Human Discomfort Caused By Ship Vibrations, Laurentiu Picu, Eugen Rusu

Journal of Marine Science and Technology

The present work analyzes the subjective responses of people exposed to transient vibrations caused by systems with a single degree of freedom. In this context, the main objective of the research was to identify the main effect of vibrations on people's well-being at work (in particular on vessels crew) and to discover those frequencies that lead to the greatest discomfort. In order to achieve this goal, 12 laboratory experiments were carried out involving ten male subjects in good health, aged between 28 and 42. The variables of the vibratory system considered are: acceleration (4.8 ÷ 8.6 m/s¡2), amplitude (1 ÷ …


Application Of Physically Based Semi-Distributed Hec-Hms Model For Flow Simulation In Tributary Catchments Of Kaohsiung Area Taiwan, Fiaz Hussain, Ray-Shyan Wu, Kai-Chun Yu Mar 2021

Application Of Physically Based Semi-Distributed Hec-Hms Model For Flow Simulation In Tributary Catchments Of Kaohsiung Area Taiwan, Fiaz Hussain, Ray-Shyan Wu, Kai-Chun Yu

Journal of Marine Science and Technology

Hydrologic modeling is a commonly used tool to understand the rainfallerunoff processes of gauged and ungauged catchments for proper quantitative estimation of water resources availability. In the present study, an attempt is made to simulate surface runoff using a physically based semi-distributed hydrological (HEC-HMS) model for four local-scale tributary catchments of Kaohsiung area Taiwan. The input physical parameters of the model were calculated and preprocessed in HEC-GeoHMS based on digital elevation model (DEM), land use, soil and hydro-meteorological data. The model performance was satisfactory with Nash Sutcliffe Efficiency (NSE) ¼ 0.51 to 0.86 and the coefficient of determination (R2) ¼ …


Evaluating Key Factors Of Container Shipping Lines From The Perspective Of High-Tech Industry Shippers, Chien-Lung Hsu, Tien-Chun Ho Mar 2021

Evaluating Key Factors Of Container Shipping Lines From The Perspective Of High-Tech Industry Shippers, Chien-Lung Hsu, Tien-Chun Ho

Journal of Marine Science and Technology

Because of the changes in customers' needs and demands created by the development of container transport in the 1960s, the global container transport business has become increasingly competitive. With the high-tech industry ranged with one of the few competitive industries in Taiwan from 2002, container shipping lines have been forced to implement innovative operating patterns to meet the evolving demands of the high-tech industry shippers. This study conducts a survey questionnaire of domestic high-tech industry shippers to explore the different factors affecting their selection of container shipping lines, evaluating the key influencing factors by maritime marketing's 4C framework: customer needs, …


Beach Topography Surveying Using Unmanned Aerial Vehicle Photogrammetry Technology, Hui-Ming Fang, Kuan-Tsung Chang, Sung-Shan Hsiao, Shih-Peng Chiang Mar 2021

Beach Topography Surveying Using Unmanned Aerial Vehicle Photogrammetry Technology, Hui-Ming Fang, Kuan-Tsung Chang, Sung-Shan Hsiao, Shih-Peng Chiang

Journal of Marine Science and Technology

The mechanisms of in situ topography changes must be identified for spatial planning in coastal areas. In this study, the authors used in situ direct measurement methods and indirect remote-sensing technologies to develop a method for beach topography surveillance. Unmanned aerial vehicles (UAVs) have advantages of high portability and mobility and low operating altitude. Therefore, a UAV was equipped with a lightweight camera and a positioning system that comprised a global positioning system and an inertial measurement unit. Aerial photogrammetry and aerial triangu-lation methods were adopted for matching image feature points to obtain the corresponding topographic points in the sand. …


Flame And Flow Characteristics Of A Plane-Jet Flame Modulated By A V-Shaped Fluidic Oscillator, Ching Min Hsu, Hsiu Feng Yang, Yuan Xu Zhang Apr 2019

Flame And Flow Characteristics Of A Plane-Jet Flame Modulated By A V-Shaped Fluidic Oscillator, Ching Min Hsu, Hsiu Feng Yang, Yuan Xu Zhang

Journal of Marine Science and Technology

The characteristic flame behaviors and velocity fields of a plane-jet flame modulated by a fluidic oscillator were experimentally studied. The flame behaviors were observed by the traditional photographic technique. The time-averaged velocity fields of the jet flame were measured by a high-speed particle image velocimeter. The temperature distributions of the jet flame were measured by an R-type thermocouple. The pulsating reacting jets issued from the side slots of the fluidic-oscillator burner formed two diffusion flames. By observing the flame behavior at around burner exit, three characteristic flame modes: attached flame, transitional flame, and lifted flame, were identified in the domain …


Due-Date Assignment And Optional Maintenance Activity Scheduling Problem With Linear Deterioreting Jobs, Chou-Jung Hsu, Suh-Jenq Yang, Dar-Li Yang Feb 2011

Due-Date Assignment And Optional Maintenance Activity Scheduling Problem With Linear Deterioreting Jobs, Chou-Jung Hsu, Suh-Jenq Yang, Dar-Li Yang

Journal of Marine Science and Technology

The focus of this work is to analyze linear deteriorating jobs in a single-machine scheduling problem with due-date assignment and maintenance activity. The linear deteriorating jobs means its processing time is an increasing function of their starting time. The objective is to minimize the total of earliness, tardiness and due-date cost. To solve the scheduling problem addressed in this work, we have to determine the job sequence, the common due-date, and the location of a maintenance activity. We show that the problem can be solved optimally in O(n2 log n) time.


Numerical Solutions Of Differential-Algebraic Equations And Its Applications In Solving Tppc Problems, He-Sheng Wang, Wei-Lun Jhu, Chee-Fai Yung, Ping-Feng Wang Feb 2011

Numerical Solutions Of Differential-Algebraic Equations And Its Applications In Solving Tppc Problems, He-Sheng Wang, Wei-Lun Jhu, Chee-Fai Yung, Ping-Feng Wang

Journal of Marine Science and Technology

In this paper, we present a numerical method for solving nonlinear differential algebraic equations (DAE’s) based on the backward differential formulas (BDF) and the Pade series. Usefulness of the method is then illustrated by a numerical example, which is concerned with the derivation of the optimal guidance law for spacecraft. This kind of problems is called trajectory-prescribed path control (TPPC) in the literature. We reformulate the problem as a Hamiltonian DAE system (usually with a higher index). After establishing the system of spacecraft dynamics, we can derive the optimal guidance law of the system by the proposed numerical method.