Effect Of Arc Plasma Sintering On The Structural And Microstructural Properties Of Fe-Cr-Ni Austenitic Stainless Steels,
2021
Center for Science and Technology of Advanced Materials, National Nuclear Energy Agency (BATAN), South Tangerang 15314, Indonesia
Effect Of Arc Plasma Sintering On The Structural And Microstructural Properties Of Fe-Cr-Ni Austenitic Stainless Steels, Parikin Parikin, M. Dani, A. Dimyati, N. D. Purnamasari, B. Sugeng, M. Panitra, A. Insani, T. H. Priyanto, S. Mustofa, Syahbuddin Syahbuddin, A. Huang
Makara Journal of Technology
X-ray diffraction techniques were performed to determine the actual crystal structure of A2 austenitic stainless steel (ASS) as-cast and A2 ASS after arc plasma sintering (APS) for 2 s. Computations were conducted on the basis of the Bragg arithmetic formula by comparing the S2 arithmetic with the interplanar spacing. The Bragg arithmetic formula is a simple series for the determination of the crystalline phase of materials based on the Miller indices of cubic shapes or other shapes. A2 ASS as-cast was identified to have a crystal structure of face-centered cubic with lattice parameter a = 3.58 Å. A similar crystal …
Trend Significance Levels Of Rain Onset And Cessation And Lengths Of The Wet And Dry Seasons In Epe, Lagos State, Nigeria,
2021
Department of Agricultural & Bio-Environmental Engineering, Yaba College of Technology, Yaba, Lagos, Nigeria
Trend Significance Levels Of Rain Onset And Cessation And Lengths Of The Wet And Dry Seasons In Epe, Lagos State, Nigeria, Adekunle Adedeji Alli, Olorunwa Eric Omofunmi
Makara Journal of Technology
This study aims to reduce crop failure resulting from a dry spell, which is the first occurrence of unsustainable rainfall that deceives farmers into planting. Thus, trends need to be tested using hypothesis, kurtosis, and other statistics to analyze the risks associated with unstable planting calendars and their possible mitigation strategies. The daily rainfall data from 1982 to 2018 were obtained from the archive of NASA/POWER SRB/FLASH, and the research location is Epe, Lagos State, Nigeria, which lies at latitude 6.585° N and longitude 3.962° E. Microsoft Excel was used to perform the tests. Results show that the null hypothesis …
Kinetic Modeling Study Of Laminar Burning Velocity Of Gasoline–Ethanol–Methanol Blends At Elevated Temperature And Pressure,
2021
Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
Kinetic Modeling Study Of Laminar Burning Velocity Of Gasoline–Ethanol–Methanol Blends At Elevated Temperature And Pressure, Ahmad Syihan Auzani, Cahyo Setyo Wibowo, Riesta Anggarani, Yulianto Sulistyo Nugroho, Bambang Sugiarto
Makara Journal of Technology
Gasoline–ethanol–methanol (GEM) blends have been considered to replace pure gasoline as spark ignition engine fuel. Their physical and chemical properties and performance and emission measurements from real engines have been reported previously. However, a fundamental study that can explain the unique results of GEM compared with those of pure gasoline is lacking. This study aims to compare the laminar burning velocity of GEM blends at different mixtures, equivalence ratios, temperatures, and pressures with that of pure gasoline. A laminar flame propagation model and reaction mechanisms from the literature were were for a numerical simulation. In this study, the chemical components …
Improvement Of Electrical Properties Of Cmc-Pva Doped With Various Contents Of Lino3 As An Application For Hybrid Polymer Electrolytes,
2021
Ionic Materials Team, Faculty of Industrial Science and Technology, Universiti Malaysia Pahang, Gambang 26300, Malaysia
Improvement Of Electrical Properties Of Cmc-Pva Doped With Various Contents Of Lino3 As An Application For Hybrid Polymer Electrolytes, Amalia Zulkifli, Norfatihah Mazuki, Ahmad Salihin Samsudin
Makara Journal of Technology
The present work was carried out with the development of hybrid polymer electrolytes (HPEs) by using carboxymethyl cellulose (CMC)–polyvinyl alcohol (PVA) doped with different contents of lithium nitrate (LiNO3) for the determination of their structural and conduction properties. The structural analysis was conducted by using Fourier transform infra-red spectroscopy and showed the interaction between the blend host polymer and ionic dopant, which formed via the coordinating site of CMC-PVA and Li+-NO3−. The complexes of CMC-PVA doped LiNO3 led to an increment in ionic conductivity, as observed by electrical impedance spectroscopy, and the sample containing 20 wt% LiNO3 obtained the highest …
Music Information Retrieval Based On Active Frequency,
2021
Informatic Engineering, Universitas Muhammadiyah Malang, Malang 65144, Indonesia
Music Information Retrieval Based On Active Frequency, Hardianto Wibowo, Wildan Suharso, Yufis Azhar, Galih Wasis Wicaksono, Agus Eko Minarno, Dani Harmanto
Makara Journal of Technology
Music is the art of combining frequencies. A balance of frequencies gives rise to a harmonious tone. Several features of music can be analyzed, and they include sociocultural background, lyrics, mood, tempo, rhythm, harmony, melody, timbre, and instrumentation. In this study, we use the frequency of instrumentation as a feature for classification because each instrument has a frequency range. To test this frequency range, we use five music genres and one music playing skill. The five genres are dangdut, electronic dance music (EDM), metal, pop/rock, and reggae. The music playing skill is acoustic. Active frequencies are tested using the k-nearest …
Predictive Delivery Man Assignment Problem Using Deep Learning,
2021
Agro-industrial Engineering Study Program, Institut Pertanian Bogor, Bogor 16680, Indonesia
Predictive Delivery Man Assignment Problem Using Deep Learning, Rahmadini Payla Juarsa, Taufik Djatna
Makara Journal of Technology
Dispatching is a critical part in current online shopping. It relates to how the delivery man assignment should minimize cost along with the service from a source to an end customer with an appropriate scheduled time. The problem arises as neither enough products to deliver nor delivery men are available for dispatch, resulting in suboptimal service and a waste of money. The study aimed to formulate the cost of restaurant dispatching for inducing a deep learning-based solution with the gated recurrent unit recurrent neural network to receive hourly order data and to engage the result for near feature delivery man …
Liner Sailing Speed Optimization Considering Wind And Waves,
2021
College of Transportation, Shandong University of Science and Technology, Qingdao, China
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,
2021
Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Hsinchu City, Taiwan
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,
2021
Department of Civil Engineering, National Central University, Taoyuan, Taiwan, R.O.C.
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,
2021
Department of Systems and Naval Mechatronic Engineering, National Cheng Kung University, Tainan, Taiwan
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,
2021
Department of Shipping and Transportation Management, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan, R.O.C.
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),
2021
Department of Mechanical and Energy Engineering, National Chia-Yi University, Chia-Yi, Taiwan
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,
2021
Department of Naval Architecture and Ocean Engineering, Seoul National University, Seoul, Republic of Korea
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,
2021
Dept. of Shipping and Transportation Management, National Taiwan Ocean University, Taiwan
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 …
3d Numerical Simulation Of Kuroshio-Induced Wake Near Green Island, Taiwan,
2021
epartment of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
3d Numerical Simulation Of Kuroshio-Induced Wake Near Green Island, Taiwan, Tien-Hung Hou, Jen-Yi Chang, Chia-Cheng Tsai, Tai-Wen Hsu
Journal of Marine Science and Technology–Taiwan
In this research, Kuroshio-induced vortex shedding in the lee of Green Island was numerically studied using the three-dimensional Princeton Ocean Model. The temporal and spatial characteristics of the vortex street were analyzed at different tidal levels, wind fields and water depths. The nu-merical results were validated by comparing with in-situ measurements from the Green Island tidal station, shipboard acoustic doppler current profiler (ADCP), conductivi-ty-temperature-depth (CTD) profiler, and moderate resolution imaging spectroradiometer (MODIS) satellite image datasets. Also, the three-dimensional results of velocity, temperature, and salinity fields were compared well with observational data. Furthermore, the influence depths of the wind effect and …
Intelligent Fuzzy Control With State-Derivative Feedback For Takagi-Sugeno Fuzzy Stochastic Singular Systems,
2021
Department of Marine Engineering, National Taiwan Ocean University, Keelung, Taiwan, R. O. C.
Intelligent Fuzzy Control With State-Derivative Feedback For Takagi-Sugeno Fuzzy Stochastic Singular Systems, Wen-Jer Chang, Kuang-Yow Lian, Cheung-Chieh Ku, Che-Lun Su
Journal of Marine Science and Technology–Taiwan
This document deals with the problem of passive fuzzy controller design with the state-derivative feedback approach for the nonlinear stochastic singular systems. Recently, the singular systems have a greater focus on literature because they can keep more physical system characteristics than conventional systems. At first, the Takagi-Sugeno fuzzy stochastic singular models are used to represent the nonlinear stochastic singular systems. Then, the state-derivative feedback approach and parallel distributed compensation method are employed to design the passive fuzzy controllers. In the design process, the Lyapunov stability conditions are developed subject to multiple performance constraints, including the passivity constraint and decay rate …
Sea Ice Warning Visualization And Path Planning For Ice Navigation Based On Radar Image Recognition,
2021
Merchant Marine College, Shanghai Maritime University, Shanghai, China
Sea Ice Warning Visualization And Path Planning For Ice Navigation Based On Radar Image Recognition, Tsung-Hsuan Hsieh, Shengzheng Wang, Huijia Gong, Wei Liu, Ning Xu
Journal of Marine Science and Technology–Taiwan
Ice navigation is currently one of the important issues in path planning studies. Most studies are using sea ice models or ice charts for large-scale path planning, but the weather and ice conditions in the polar waters usually change quickly and are not easy to predict. Under these conditions, small-scale path planning that can be adjusted in time for sea ice collision avoidance is needed. This study uses marine radar imaging to reconstruct the ice navigation scene, and establishes a visual-ization function of sea ice warning on the radar image. We combine the bidirectional rapidly-exploring random tree (B-RRT) algorithm and …
Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria,
2021
Department of Business Administration, National Taipei University of Business
Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria, Wen-Cheng Lin, Hsin-Hung Cheng
Journal of Marine Science and Technology–Taiwan
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,
2021
School of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, China
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–Taiwan
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 …
Near-Shore Sediment Transport Under Cnoidal Waves Using Particle Image Velocimetry,
2021
Florida Institute of Technology
Near-Shore Sediment Transport Under Cnoidal Waves Using Particle Image Velocimetry, Jenna Rose Katrina
Theses and Dissertations
With future trends showing a higher percentage of the human population living along the coast, coastal resilience is a significant topic of concern for many researchers. The purpose of this research was to analyze near-shore sediment transport under different wave parameters using the technique of Particle Image Velocimetry (PIV) and laboratory studies for linear and nonlinear cnoidal waves. At the deeper extent of the nearshore profile, waves will tend to be linear, having an Ursell number less than 40, with little or no net sediment transport due to orbital velocities. The velocities are the same under the crest and trough …
