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2020

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A New Complex Marine Unmanned Platform And Field Test, Jihyeong Lee, Han-Sol Jin, Hyunjoon Cho, Jiafeng Huang, Sang-Ki Jeong, Dae-Hyeong Ji, Hyeung-Sik Choi Dec 2020

A New Complex Marine Unmanned Platform And Field Test, Jihyeong Lee, Han-Sol Jin, Hyunjoon Cho, Jiafeng Huang, Sang-Ki Jeong, Dae-Hyeong Ji, Hyeung-Sik Choi

Journal of Marine Science and Technology–Taiwan

This paper presents the development of a new complex marine unmanned platform composed of an unmanned surface vehicle (USV) and a remotely operated vehicle (ROV), and the results of a sea test. The platform structure, control system, sensor system, and control algorithm were developed and are introduced. The complex platform collects information of the underwater structures, such as the wall, floor, and piers and harbors. Using a tether cable, the ROV is connected to the USV for power supply and to receive a large amount of underwater data obtained using a sonar scanner or a camera in real time. The …

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A Study On Hydrodynamic Forces Induced By Liquid Tank Of Lng Carrier In Waves Based On Experiment And Recurrent Neural Network, Van Minh Nguyen, Thi Thanh Diep Nguyen, Hyeon Kyu Yoon Dec 2020

A Study On Hydrodynamic Forces Induced By Liquid Tank Of Lng Carrier In Waves Based On Experiment And Recurrent Neural Network, Van Minh Nguyen, Thi Thanh Diep Nguyen, Hyeon Kyu Yoon

Journal of Marine Science and Technology–Taiwan

The sloshing of liquid in a partially filled tank is of great concern to aerospace vehicles, road vehicles and ships due to complex nonlinear motion involving the free surface of the liquid. Sloshing is a type of violent liquid motion that is created by forces such as an impact and breaking waves. Oscillation of the liquid in the vessel may threaten navigation safety. This paper attempts to predict the hydrodynamic forces induced by the motion of liquid inside a tank based on experiment and Recurrent Neural Network (RNN). The experiment of sloshing test is carried out using the Stewart platform …

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Collision Warning System For Small Maritime Autonomous Surface Ships, Won-Sik Kang, Young-Soo Park, Jeong-Bin Yim Dec 2020

Collision Warning System For Small Maritime Autonomous Surface Ships, Won-Sik Kang, Young-Soo Park, Jeong-Bin Yim

Journal of Marine Science and Technology–Taiwan

In this study, wireless communication technologies used in road and marine traffic are compared and analyzed to develop a collision warning system for small maritime autonomous surface ships based on sufficient testing and technologically advanced wireless access in vehicular environment (WAVE) communication technology. Outstanding communication technologies, such as WAVE, have been used as the core technology for the infrastructural development of an intelligent transport system (ITS) as well as autonomous vehicles in many countries and industries. In WAVE communication, information is transmitted in 100-ms intervals. Therefore, it is feasible to maintain control of ships by fully supplementing the update interval …

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Modeling Navigator Errors In Collisions Using Hidden Markov Models, Deuk-Jin Park, Jeong-Bin Yim, Chun-Ki Lee Dec 2020

Modeling Navigator Errors In Collisions Using Hidden Markov Models, Deuk-Jin Park, Jeong-Bin Yim, Chun-Ki Lee

Journal of Marine Science and Technology–Taiwan

Understanding navigator errors can be used as a basis for preventing collisions. Here, Hidden Markov Models (HMMs) are applied to navigator errors of fishing and merchant ships in collisions. Information on navigator errors providedin accident investigation reports issued by the Korean Maritime Safety Tribunal is surveyed. The surveyed information is converted into data using the framework of slips, lapses, and mistakes proposed in this study. The results of framework data states are inferred using the unsupervised learning of HMMs, with sequences of navigator errors contained in the error data. The expected errors learned using the navigator error models for fishing …

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Remote Sensing Analysis Of Cold Water Temporal And Spatial Variability In The East Sea, Suk Yoon, Hyun Yang Dec 2020

Remote Sensing Analysis Of Cold Water Temporal And Spatial Variability In The East Sea, Suk Yoon, Hyun Yang

Journal of Marine Science and Technology–Taiwan

In this study, we monitored temporal and spatial variability in summer cold water events in the East Sea of Korea. We defined cold water as seawater that is ≥ 5°C colder than the surrounding area. When cold water expands or changes in propagation direction, the National Institute of Fisheries Science (NIFS) of Korea issues a cold water upwelling warning to prevent aquafarm damage. To understand cold water effects, we analyzed the causes of continuous and strong cold water events, and propagation thereof, using satellite and in situ data for summer to autumn in the period 2011–2019. To investigate the cold …

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Short-Term Fatigue Damage Of Tethers Of Long-Span Floating Cable Supported Bridges Under Harsh Waves, Deokhee Won, Keesei Lee, Young-Jong Kang, Seungjun Kim Dec 2020

Short-Term Fatigue Damage Of Tethers Of Long-Span Floating Cable Supported Bridges Under Harsh Waves, Deokhee Won, Keesei Lee, Young-Jong Kang, Seungjun Kim

Journal of Marine Science and Technology–Taiwan

A floating bridge can be effectively used for sea-crossing in deep water. Because the superstructure of the bridge is supported by floating substructures with pontoons, the conventional fixed piers, towers, foundations, and piles are not required. Instead, a rational mooring system can be used to strictly maintain the target position of the floating substructures against environmental loads, including winds, waves, and currents. Recently, long-span cable-supported bridges with floating towers were investigated and found to overcome the limitations of conventional cable-supported bridges, when used as sea-crossing infrastructure. To design the moorings for very large floating structures, the structural safety should be …

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Seismic Attribute Recognition Technology Of Magmatic Rock Intrusive Coal Seam, Wu Bin, Meng Fanbin Dec 2020

Seismic Attribute Recognition Technology Of Magmatic Rock Intrusive Coal Seam, Wu Bin, Meng Fanbin

Coal Geology & Exploration

In order to increase the degree of production of CBM development blocks, when the production of a single well enters a decline period, the development plan needs to be adjusted, and the production increase and stability can be achieved through the measures such as layer adjustment or layer compensation. In terms of time, it is believed that the main coal seam should be developed first when it is put into production. After the decline period, the secondary main coal seam should be supplemented and combined; in space, combined with the development dynamics, the analytic hierarchy process is used to determine …

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Technology And Application Of High Efficiency Gas Extraction By Directional Long Borehole Hydraulic Fracturing In Coal Seams Of Medium Hardness And Low Permeability, Guo Chaoqi, Zhao Jizhan, Li Xiaojian, Zhang Jingfei, Wu Shengli, Chen Dongdong, Huang Xingli, Li Baojun Dec 2020

Technology And Application Of High Efficiency Gas Extraction By Directional Long Borehole Hydraulic Fracturing In Coal Seams Of Medium Hardness And Low Permeability, Guo Chaoqi, Zhao Jizhan, Li Xiaojian, Zhang Jingfei, Wu Shengli, Chen Dongdong, Huang Xingli, Li Baojun

Coal Geology & Exploration

Grouting quality test is the key technology for efficient development and utilization of waste land in the goaf of a coal mine, it is of great significance to evaluate the stability of the site and the safety of construction after goaf management. Based on many engineering practices, this paper summarizes the evaluation method of the qualified standards of the grouting quality and the errors existed in the testing work. The results proved that the quality inspection after grouting is a systematic work. The test method could be optimized according to the characteristics of the construction and grouting design requirements, following …

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Numerical Simulation Of Fractured Water-Conducting Zone By Considering Native Fractures In Overlying Rocks, Li Ruirui, Chen Luwang, Ou Qinghua, Chen Yifei, Wang Yingxin, Ge Rutao, Peng Zhihong Dec 2020

Numerical Simulation Of Fractured Water-Conducting Zone By Considering Native Fractures In Overlying Rocks, Li Ruirui, Chen Luwang, Ou Qinghua, Chen Yifei, Wang Yingxin, Ge Rutao, Peng Zhihong

Coal Geology & Exploration

The intelligent accurate coal mining needs to construct the high-precision and transparent 3D geological model, and the seismic data interpretation integrated into the dynamic roadway data provide data support for the model. The geological model of roadway is established and forward modeling is carried out to analyze the difference of seismic characteristics caused by a roadway. Based on curvature attribute principle, various seismic curvature attributes were applied to seismic data interpretation, guide the roadway recognition in the seismic data. The coal seam 2 of CJT coalfield was selected as the research object, and the high-quality seismic data and various attribute …

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Improvement And Optimization Of Permeability And Strength Properties Of Loess, Zhu Min, Ni Wankui, Yuan Kangze, Li Lan, Li Xiangning, Wang Haiman Dec 2020

Improvement And Optimization Of Permeability And Strength Properties Of Loess, Zhu Min, Ni Wankui, Yuan Kangze, Li Lan, Li Xiangning, Wang Haiman

Coal Geology & Exploration

In order to study the development of secondary faults and fracture, a boundary element method (BEM) combined with seismic interpretation of main faults and geo-mechanics is discussed. Firstly, with the Anderson's theory of faulting, the classification of secondary fault tectonic evolution events is improved under the combination of fault and stress; secondly, the stress tensor order reduction and linear superposition principle are applied to simplify the stress and displacement balance equation, and the Monte Carlo method is used to inverse the paleo-stress field. After all, the equilibrium equation of stress, strain and discontinuous displacement is solved to obtain the current …

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Dynamic Modelling And Experimental Results Of A Ray-Type Hybrid Underwater Glider With A Dualbuoyancy Engine, Ngoc-Duc Nguyen, Hyeung-Sik Choi, Sung-Wook Lee, Wen-Hsiang Hsieh, Sang-Ki Jeong, Dae-Hyeong Ji Dec 2020

Dynamic Modelling And Experimental Results Of A Ray-Type Hybrid Underwater Glider With A Dualbuoyancy Engine, Ngoc-Duc Nguyen, Hyeung-Sik Choi, Sung-Wook Lee, Wen-Hsiang Hsieh, Sang-Ki Jeong, Dae-Hyeong Ji

Journal of Marine Science and Technology–Taiwan

For ocean observation and exploration, underwater gliders (UG) have shown their efficient long-range operation with buoyancy propulsion. The current Torpedo-shape UGs have small buoyancy capacity and insufficient space for batteries and sensors. In this paper, a Ray-type hybrid underwater glider (RHUG) is developed with new hull design, dual-buoyancy engine, and thrusters. The control system of the RHUG is constructed for gliding motion. To understand the characteristic of the RHUG, dynamic modelling of the dual-buoyancy engine was established. To verify the proposed dynamics model, a navigation experiment using the developed RHUG platform was carried out. Through comparison between experiment and simulation …

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Penggunaan Neurodevelopmental Treatment Pada Kasus Dandy Walker Syndrome, Aditya Denny Dec 2020

Penggunaan Neurodevelopmental Treatment Pada Kasus Dandy Walker Syndrome, Aditya Denny

Jurnal Sosial Humaniora Terapan

Dandy Walker Syndrome (DWS) is a syndrome that occurs in a child due to a malformation that occurs during the development of the cerebellum and the fourth ventricle. One of the clinical manifestations of DWS is a balance disorder. The purpose of this case study was to determine the effectiveness of Neurodevelopmental Treatment (NDT) on standing balance in DWS cases with the Pediatric Balance Scale (PBS) parameter. The clinical question arises, how is the effectiveness of NDT to improve balance with the parameters of the pediatric balance scale in cases of dandy walker syndrome? To answer clinical problems, online literature …

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Diffusing New Media As Know-How Digital Communication In Troubleshoot Maintenance Of Pico Hydro Technology In Bengkulu, Indonesia Dec 2020

Diffusing New Media As Know-How Digital Communication In Troubleshoot Maintenance Of Pico Hydro Technology In Bengkulu, Indonesia

Jurnal Sosial Humaniora Terapan

Communication has an important role for spreading messages and ideas through various mediums. This research explains the important role of new media in community engagement activities and the dissemination of new information, innovations and technologies that have been done in 2017, especially for the graphic design via the internet on Pico Hydros information technology in Batu Roto village, Bengkulu province, Indonesia. Community involvement itself is based on a special multidisciplinary perspective of communication and engineering. Pico Hydro is commonly used worldwide to generate electricity in rural areas, making it very useful for rural electrification. We conduct research to meet the …

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Literasi Akuntansi Dan Keuangan Untuk Meningkatkan Kapasitas Dan Kualitas Sumber Daya Manusia Pada Koperasi Simpan Pinjam, Titis Wahyuni Dec 2020

Literasi Akuntansi Dan Keuangan Untuk Meningkatkan Kapasitas Dan Kualitas Sumber Daya Manusia Pada Koperasi Simpan Pinjam, Titis Wahyuni

Jurnal Sosial Humaniora Terapan

Sharia savings and loan cooperatives provide benefits for Muslims who need fast funds to invest and develop business without being subject to usury. Improvement of accounting and financial skills is needed for cooperative managers to avoid financial failures that can lead to the closure of cooperatives. This can be achieved by providing a series of accounting and finance training to cooperative managers. The health condition of the savings and loan cooperatives has to be healthy so that they can continue to provide services to people in need. However, many savings and loan cooperatives find it difficult to carry out health …

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Pengaruh Asosiasi Merek Terhadap Keputusan Pembelian Konsumen Iphone (Studi Kasus Mahasiswa/I Program Pendidikan Vokasi Ui), Arius Krypton Dec 2020

Pengaruh Asosiasi Merek Terhadap Keputusan Pembelian Konsumen Iphone (Studi Kasus Mahasiswa/I Program Pendidikan Vokasi Ui), Arius Krypton

Jurnal Sosial Humaniora Terapan

No abstract provided.

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Strategi Kampanye Sosial Anti Stigma Dan Perilaku Hidup Sehat Terhadap Penderita Kusta Dan Orang Yang Pernah Mengalami Kusta (Oypmk) Dec 2020

Strategi Kampanye Sosial Anti Stigma Dan Perilaku Hidup Sehat Terhadap Penderita Kusta Dan Orang Yang Pernah Mengalami Kusta (Oypmk)

Jurnal Sosial Humaniora Terapan

This study describes a social campaign conducted by university academics. The social campaign that is being carried out is an anti-stigma campaign to counteract the negative stigma for people affected by leprosy (OYPMK) and a campaign for healthy living habits, especially for oral and dental health. The research was conducted descriptively to see what social campaign strategies were implemented in an effort to eliminate negative stigma and encourage healthy living behaviors. The data displayed is descriptive quantitative and qualitative from the observations and interviews result. The findings show that there are key messages that are used in the campaign to …

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Vokhum Fest: A Specialized Integrated Marketing Communication Event Towards Small Medium Enterprises Brand Management And Youth Social Welfare Dec 2020

Vokhum Fest: A Specialized Integrated Marketing Communication Event Towards Small Medium Enterprises Brand Management And Youth Social Welfare

Jurnal Sosial Humaniora Terapan

Integrated Marketing Communication is an essential concept in marketing field. It is used worldwide to marketing and communicating in vary kind of business both in big enterprise or small enterprise. This article describes the implementation of IMC on an event marketing called Vokhum Fest as a community engagement program. The event is a collaboration between Vocational Education Program Universitas Indonesia lecturers, assistant lecturers, students and 12 Small Medium Enterprises (SMEs) in Jakarta Greater Area ranging from products to services also for the most part organized by youth. The purpose and benefits of this research are to see the impact of …

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Late Pleistocene Sedimentary Features And The Palaeoclimatic Background In Hongsibao Basin, Li Zhenhong, Cui Jiawei, Li Chaozhu, Jiang Boyu, Huang Ting Dec 2020

Late Pleistocene Sedimentary Features And The Palaeoclimatic Background In Hongsibao Basin, Li Zhenhong, Cui Jiawei, Li Chaozhu, Jiang Boyu, Huang Ting

Coal Geology & Exploration

The chuck is an important part of the coal mine tunnel drilling rig. The performance of the chuck directly affects the efficiency and quality of drilling. Aiming at the problems of the rubber cylinder hydraulic chuck. a new radial piston hydraulic chuck is studied. The objective of this paper is to devise a new radial piston hydraulic chuck instead of rubber-sleeve hydraulic chuck. Then, the motion mathematical model of radial piston hydraulic chuck was established based on the radial piston chuck clamping and loosening of system structure and working principle. At the same time, a dynamic co-simulation of chuck hydraulic …

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Development Of Collision Avoidance Algorithm Based On Consciousness Of Ship Operator, Eunkyu Lee, Young-Soo Park, Minjeong Park, Myoung-Ki Lee, Eunbi Park, In-Young Gong Dec 2020

Development Of Collision Avoidance Algorithm Based On Consciousness Of Ship Operator, Eunkyu Lee, Young-Soo Park, Minjeong Park, Myoung-Ki Lee, Eunbi Park, In-Young Gong

Journal of Marine Science and Technology–Taiwan

Several collision avoidance algorithms employing various methods have been developed to date. In this paper, a collision avoidance algorithm is proposed based on the potential assessment of risk (PARK) model, which is a maritime traffic risk assessment model based on the characteristics of the Korean coastal regions and the consciousness of a ship’s operator. The proposed collision avoidance algorithm is intended to be used in the transition period during which autonomous and human-operated ships sail simultaneously. The algorithm avoids collisions using the PARK model that reflects the International Regulations for Preventing Collisions at Sea. Situations such as head-on, crossing, overtaking, …

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Significance Of Reagents Addition Sequence On Iron Anionic Reverse Flotation And Their Adsorption Characteristics Using Qcm-D, Ying Hou, Ahmed Sobhy, Yue Wang Dec 2020

Significance Of Reagents Addition Sequence On Iron Anionic Reverse Flotation And Their Adsorption Characteristics Using Qcm-D, Ying Hou, Ahmed Sobhy, Yue Wang

Mining Engineering Faculty Research & Creative Works

To explore the influence of reagents addition sequence of the pH regulator and the starch depressant on the anionic reverse flotation of iron oxide, flotation conditional experiments were performed on mixed low-intensity and high-gradient magnetic concentrates which is the flotation feed acquired from the iron processing plant. Besides, quartz crystal micro-balance with dissipative (QCMD) was conducted to detect the adsorption phenomena of the flotation reagent on iron oxide sensors at different addition orders. The outcomes showed that the flotation performance using the pH regulator prior to the depressant was the best. For example, at 1.6 kg/Mg starch dosage, the recovery …

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Identifying High-Collision Potential Vessel-Bridge Pairs In Vessel Traffic Service, Jeong-Bin Yim, Chun-Ki Lee Dec 2020

Identifying High-Collision Potential Vessel-Bridge Pairs In Vessel Traffic Service, Jeong-Bin Yim, Chun-Ki Lee

Journal of Marine Science and Technology–Taiwan

Collision risk assessment for maritime traffic monitoring in vessel traffic service (VTS) is a key technology for ensuring the safety of both vessels and bridges. This study proposes a risk assessment methodology using a single measure of collision risk ratio that could assist in reducing the cognitive load of VTS operators. To explain the proposed method, we first define the semantic and mathematical relationship of vessel– bridge pier collisions; then, we establish the risk assessment framework using the collision risk ratio by combining deviation angle and stopping distance probabilities. To validate the proposed method, we conducted an experiment in the …

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We Are All Gig Workers Now: Online Platforms, Freelancers & The Battles Over Employment Status & Rights During The Covid-19 Pandemic, Orly Lobel Dec 2020

We Are All Gig Workers Now: Online Platforms, Freelancers & The Battles Over Employment Status & Rights During The Covid-19 Pandemic, Orly Lobel

San Diego Law Review

Since the early days of the Coronavirus pandemic, unemployment rates leapt to the highest they have been since 1975. Congress passed the Coronavirus Aid, Relief, and Economic Security (CARES) Act in March 2020, a $2 trillion relief package, offering augmented unemployment relief not only to employees but also to the self-employed, including gig workers. The Families First Coronavirus Response Act (FFCRA) was passed to provide sick leave in the form of tax credits that also extended to the self-employed. Beyond the governmental responses, platform companies offered new limited relief to their workers in the form of sick leave, even as …

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Crisis Standards Of Care And State Liability Shields, Valerie Gutmann Koch Dec 2020

Crisis Standards Of Care And State Liability Shields, Valerie Gutmann Koch

San Diego Law Review

The COVID-19 pandemic has overwhelmed many U.S. systems—including the already-strained medical system—intended to protect and care for its citizens. In the United States, New York became the first epicenter of the pandemic, accounting for approximately five percent of global COVID-19 cases by March 2020. Hospitals, health care providers, and policymakers soon recognized that, in New York and beyond, they faced a bleak reality that—if the spread of the virus could not be controlled—there would soon not be enough ventilators for all patients who needed them, despite hospitals practicing “surge capacity” to reduce the need for ventilators by canceling or postponing …

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Prisons And Pandemics, Camila Strassle, Benjamin E. Berkman Dec 2020

Prisons And Pandemics, Camila Strassle, Benjamin E. Berkman

San Diego Law Review

This Article focuses on how to balance public health, public safety, and incarcerated people’s legal rights when implementing a program for early release from confinement. Ethical, epidemiological, and legal arguments all point to a need for an immediate reduction in the incarcerated population. However, this leaves open several points of reasonable disagreement about how to manage early release. These include how to set priorities for processing and releasing individuals across the country. For example, officials could prioritize screening individuals who are housed in facilities that have been hit hard by infection; or by screening individuals who have a safe place …

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Experimental And Numerical Investigations On The Hydrodynamic Characteristics Of The Planar Motion Of An Open-Frame Remotely Operated Vehicle, Ying-Fei Zan, Rui-Nan Guo, Li-Hao Yuan, Shi-Peng Wang, Da-Zhong Zhang, Shi-Jing Xu, Zhao-Hui Wu Dec 2020

Experimental And Numerical Investigations On The Hydrodynamic Characteristics Of The Planar Motion Of An Open-Frame Remotely Operated Vehicle, Ying-Fei Zan, Rui-Nan Guo, Li-Hao Yuan, Shi-Peng Wang, Da-Zhong Zhang, Shi-Jing Xu, Zhao-Hui Wu

Journal of Marine Science and Technology–Taiwan

In this study, the longitudinal, sideways, vertical, and sideslip motions of an open-frame remotely operated vehicle (ROV) were experimentally and numerically investigated. The open-frame ROV was designed to be asymmetric in both the longitudinal and vertical directions to achieve special functionalities. A physical ROV model was tested in a towing tank with different velocities and sideslip angles in the horizontal and vertical planes. A numerical simulation was conducted with the same working conditions used in the scaled model tests by using a segregated flow solver based on Reynolds-averaged Navier–Stokes equations. This study investigated the effect of the hydrodynamic forces (moments) …

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An Enhanced Sliding Mode Control Method For Wave Compensation System Of Ship-Mounted Cranes With Roll Motions And Parametric Uncertainties, Hai-Yan Qiang, Si Xie, Zhi-Qiang Xu, You-Gang Sun Dec 2020

An Enhanced Sliding Mode Control Method For Wave Compensation System Of Ship-Mounted Cranes With Roll Motions And Parametric Uncertainties, Hai-Yan Qiang, Si Xie, Zhi-Qiang Xu, You-Gang Sun

Journal of Marine Science and Technology–Taiwan

Ship-mounted cranes are widely used in offshore constructions, resource exploitation and marine salvages, to transfer payloads. Due to serious sea conditions, unexpected motions of the ships caused by the wave will probably pose serious efficiency and security issues. Thus, the wave compensation system has become necessary equipment for the shipmounted crane. But wave-induced motions of the ship, parametric uncertainties and nonlinearities remain challenges for control of wave compensation systems, which needs to be solved urgently. In this paper, the mathematical model of the wave compensation system is established firstly. Then, a sliding mode controller is presented and the stability is …

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Study On Underwater Navigation For Underwater Track Vehicle, Dae-Hyeong Ji, Hyeung-Sik Choi, Sang-Ki Jeong, Hyun-Joon Cho, Ji-Hyeong Lee, Wen-Hsiang Hsieh Dec 2020

Study On Underwater Navigation For Underwater Track Vehicle, Dae-Hyeong Ji, Hyeung-Sik Choi, Sang-Ki Jeong, Hyun-Joon Cho, Ji-Hyeong Lee, Wen-Hsiang Hsieh

Journal of Marine Science and Technology–Taiwan

In this study, an underwater navigation algorithm was developed to apply a navigation system to an underwater track vehicle (UTV). Generally, a Doppler velocity log (DVL) is used to obtain the velocity information of underwater vehicles. However, a DVL cannot be used in a UTV owing to vehicle vibration and limited sensing distance. Hence, dead reckoning navigation is typically used, which results in severe errors in altitude and position values over long periods of operation. To address these problems, in this study, we developed a new underwater navigation system for a UTV using navigation sensors comprising an inertial navigation system, …

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A Study On The Analysis Of Minimum Speed Control Effect Using Queue Model Focused On Busan Port, Sangwon Park, Won-Sik Kang, Young-Soo Park Dec 2020

A Study On The Analysis Of Minimum Speed Control Effect Using Queue Model Focused On Busan Port, Sangwon Park, Won-Sik Kang, Young-Soo Park

Journal of Marine Science and Technology–Taiwan

VTS aims to increase the efficiency of maritime traffic in two ways. The first is a decrease in marine accidents, and the second is an increase in the utilization rate of infrastructure such as waterways and port facilities. This means that, if safety is guaranteed, efficiency must also be considered in the VTS. The purpose of this study is to quantitatively analyze the effects of speed regulation under safe conditions for an efficient use of waterways. A model was developed using a queue approach, and the effect of the waiting time according to the minimum speed proposal was analyzed through …

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Does Gender Difference Matter In Job Satisfaction? A Case Of Academicians In Karnataka, Shreemathi S. Mayya, Maxie Martis, P. Sureshramana Mayya Dec 2020

Does Gender Difference Matter In Job Satisfaction? A Case Of Academicians In Karnataka, Shreemathi S. Mayya, Maxie Martis, P. Sureshramana Mayya

Open Access archive

Learning organizations are the hubs of knowledge generation and dissemination. Academicians need organizational support to accomplish these time-consuming tasks effectively. The academician, when satisfied with his or her own work, is committed to the organization and demonstrates higher work productivity and work quality. The present study, with a cross-sectional design, was aimed to assess the level of job satisfaction (gender-wise) and its determinants, among academicians, in the institutions of higher education in Karnataka. The study used a validated job satisfaction questionnaire developed by the researchers. The overall job satisfaction was satisfactory and did not differ between the male and female …

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Methods To Analyze Likert-Type Data In Educational Technology Research, Li-Ting Chen, Leping Liu Dec 2020

Methods To Analyze Likert-Type Data In Educational Technology Research, Li-Ting Chen, Leping Liu

Journal of Educational Technology Development and Exchange (JETDE)

Likert-type items are commonly used in education and related fields to measure attitudes and opinions. Yet there is no consensus on how to analyze data collected from these items. In this paper, we first synthesized literature on strategies for analyzing Likert-type data and provided computing tools for these strategies. Secondly, to examine the use and analysis of Likert-type data in the field of educational technology, we reviewed 424 articles that were published in the journal Educational Technology Research and Development between 2016 and 2020. Our review showed that about 50% of the articles reported Likert-type data. A total of 139 …

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