• Journal of Drive and Control
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• v.10 no.4
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• pp.22-28
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• 2013

Mechanical and electrical properties of a DDV(Direct Drive servo Valve) with electric feedback are analysed via reverse analysis technique in this work. The DDV is disassembled and mechanical parameters, such as spool mass, spring stiffness and port size are identified. The servo amplifier, which is built in the valve, is reversely analysed and the control scheme and gains for several control actions are also identified. The electrical feedback for spool displacement improves much better the valve performance, such as hysteresis and dynamic bandwidth frequency, than an ordinary mechanical feedback valve. Integrating control action with very large gain was adopted in the valve amplifier, and it seemed to give high performance.

• Journal of the Korea Society of Computer and Information
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• v.24 no.5
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• pp.131-137
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• 2019

This study was aimed to identify a study on risk perception and safety knowledge and awareness of scuba diver. In order to achieve this purpose, a total of 310 customers over the age of 20 were selected as study participants form diving pools and dive resort in Seoul, Gyeonggi, Gangwon, Gyeongsang area using the convenience sampling method. However, only data from 295 customers were used after screening the data for reliability. The instrument for data collection was a questionnaire, and descriptive statistics, inter-item consistency reliability, t-test, ANOVA, post hoc test, correlation analysis, pearson chi-square test were conducted on the data using the SPSS 21.0 version statistical package program. The followings are the results: First, risk perception differs significantly according to age, education level, occupation and participation period. Second, participation period and safety knowledge have positive correlation.

• Journal of the Korea Society of Computer and Information
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• v.24 no.4
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• pp.161-167
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• 2019

In this paper, we propose a study on awareness of first aid of scuba diver. In order to achieve this purpose, a total of 310 customers over the age of 20 were selected as study participants form diving pools and dive resort in Seoul, Gyeonggi, Gangwon, Gyeongsang province area using the convenience sampling method However, only data from 295 customers were used after screening the data for reliability. The instrument for data collection was a questionnaire, and descriptive statistics, inter-item consistency reliability, pearson chi-square test were conducted on the data using the SPSS 21.0 version statistical package program. The followings are the results: The level differ significantly according hemorrhage, abrasion, sprain, fracture, fever, arrest, airway obstruction. As a result of analyzing the difference of first aid recognition according to the level of scuba diver, we found bleeding patients, abrasions, sprains, fractures, high heat exposure patients, cardiac arrest patients. There was a statistically significant difference in the level of airway obstruction due to food.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.3
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• pp.152-160
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• 2024

In the event of a maritime accident, search plans have traditionally been planned using experiential methods. However, these approaches cannot guarantee safety when the scale of a maritime accident increases. Therefore, this study proposes a model utilizing discrete event simulation (DES) to predict the diving time for compartment searches of a ship located on the seabed. The discrete event simulation model was created by applying the DEVS formalism. The M/V Sewol sinking was used as an example to simulate how to effectively navigate compartments of different sizes. The simulation results showed the optimal dive time with the number of decompression chambers needed to navigate the compartment as a variable. Based on this, we propose a methodology for efficient navigation planning while ensuring diver safety.

• International journal of advanced smart convergence
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• v.13 no.1
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• pp.122-128
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• 2024

This study delves into the unique transformation of South Korea's elderly population, distinctively termed 'Nomad Silver'. Characterized by individuals aged 65 and above who actively seek novel experiences and embrace new activities, this demographic shift signifies a departure from traditional perceptions of the elderly. The Nomad Silver cohort, distinguished by their significant economic influence and evolving needs, necessitates a tailored approach to healthcare services. This paper underscores the importance of comprehending both the fundamental biological needs and the personalized desires of the Nomad Silver, aiming to enhance their satisfaction and overall well-being. Hospitals, in response, should innovate their services to resonate with the emotional, psychological, and social facets of this age group. Consequently, the paper proposes a four-pronged strategy for hospitals to adapt: comprehensive healthcare provision, patient-centric service development, senior health education coupled with community engagement, and establishing a generational bridge hub. Furthermore, the paper posits that catering to the Nomad Silver not only promises substantial financial gains for hospitals but also fosters new business opportunities across various sectors.

• Journal of Navigation and Port Research
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• v.32 no.1
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• pp.109-114
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• 2008

This study is about the status and comparison of recreational scuba diving certification system in Southeast Asia countries. For the collection of the information, the contents of the numerous corresponding Internet sites were utilized, related documents were surveyed. And to supplement the information extensive interviews were held with the representatives of tourism department of many countries as well as staffs of diving associations, resort operators and diving instructors during various 2007 Dive Expos held in Southeast countries. In this paper, the relation between scuba certification and international standards were introduced for better understanding of the certification system. The research result shows that the scuba diving industry plays an important role in their country's tourism and the certification market of the Southeast Asia has grown to be greater than 30% of the world total market. However due to the facts that the scuba activity is originated from the western world and the controlling headquarters of the most certification agency are also located there, Southeast countries cannot take any leading roles in the scuba diving policies and systematic issues. Accordingly any modifications or improvements are expected to be very difficult. Also while Europeans and Americans have launched the programs and organizations for the quality assurance by cooperating with the international standards, but no such activity has yet appeared on the surface in Southeast Asia. According to the investigation the necessity will become bigger in near future.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.735-742
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• 2010

This paper reviewed the diving standards for underwater work in hostile environment and analyzed applied Navy diving technique, diving equipments and procedure for rescue operation of Navy ship Cheonan's missing crew occurred near Bak Ryung Do in March 2010. The operation was done beyond the international standards and safety practice, and by considering the nature of the mission, urgency and effectiveness as well as the detailed facts such as duration and depth of the dive, type of work to be performed, environmental conditions, time constraints of early rescue operation, it is analyzed that using air scuba diving system was adequate.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.529-542
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• 2017

Control of plant diseases is largely dependent on use of agrochemicals. However, there are widening gaps between our knowledge on plant diseases gained from genetic/mechanistic studies and rapid translation of the knowledge into target-oriented development of effective agrochemicals. Here we propose that the time is ripe for computer-aided drug discovery/design (CADD) in molecular plant pathology. CADD has played a pivotal role in development of medically important molecules over the last three decades. Now, explosive increase in information on genome sequences and three dimensional structures of biological molecules, in combination with advances in computational and informational technologies, opens up exciting possibilities for application of CADD in discovery and development of agrochemicals. In this review, we outline two categories of the drug discovery strategies: structure- and ligand-based CADD, and relevant computational approaches that are being employed in modern drug discovery. In order to help readers to dive into CADD, we explain concepts of homology modelling, molecular docking, virtual screening, and de novo ligand design in structure-based CADD, and pharmacophore modelling, ligand-based virtual screening, quantitative structure activity relationship modelling and de novo ligand design for ligand-based CADD. We also provide the important resources available to carry out CADD. Finally, we present a case study showing how CADD approach can be implemented in reality for identification of potent chemical compounds against the important plant pathogens, Pseudomonas syringae and Colletotrichum gloeosporioides.

• Smart Structures and Systems
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• v.8 no.1
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• pp.39-52
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• 2011

We are developing a biomimetic robot based on the Sea Lamprey. The robot consists of a cylindrical electronics bay propelled by an undulatory body axis. Shape memory alloy (SMA) actuators generate propagating flexion waves in five undulatory segments of a polyurethane strip. The behavior of the robot is controlled by an electronic nervous system (ENS) composed of networks of discrete-time map-based neurons and synapses that execute on a digital signal processing chip. Motor neuron action potentials gate power transistors that apply current to the SMA actuators. The ENS consists of a set of segmental central pattern generators (CPGs), modulated by layered command and coordinating neuron networks, that integrate input from exteroceptive sensors including a compass, accelerometers, inclinometers and a short baseline sonar array (SBA). The CPGs instantiate the 3-element hemi-segmental network model established from physiological studies. Anterior and posterior propagating pathways between CPGs mediate intersegmental coordination to generate flexion waves for forward and backward swimming. The command network mediates layered exteroceptive reflexes for homing, primary orientation, and impediment compensation. The SBA allows homing on a sonar beacon by indicating deviations in azimuth and inclination. Inclinometers actuate a bending segment between the hull and undulator to allow climb and dive. Accelerometers can distinguish collisions from impediment to allow compensatory reflexes. Modulatory commands mediate speed control and turning. A SBA communications interface is being developed to allow supervised reactive autonomy.

• Journal of Korea Multimedia Society
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• v.16 no.11
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• pp.1348-1356
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• 2013

Disney Animation has showed not only artistic excellence but also technological innovations through a lot of animation films that they released. Especially with the unique concept that free-willed game characters dive into different worlds of games in animation film, received both critical and commercial acclaim for its stunning visuals and outstanding CG (computer graphics) effects. The purpose of this study is to analyze different styles of game worlds, Disney's layout pipeline, and in-house camera capture system used in . This paper analyzes that three game worlds in this film such as Fix-It Felix Jr., Sugar Rush, and Hero's Duty express different styles by using appropriate character animation and camera movements. Especially Hero's Duty game which new in-house camera capture system is extensively used maximizes unseen visuals by perfectly making realistic and believable game world. Disney's newly developed in-house camera capture system, which is used in this film for the first time, allows real camera's motion and shake and real-time camera's movement and correction within animation set. Result of this study proves that this system improves directing of feature animation and enhance efficiency of the layout department's production process. Therefore, it contributes to a great extent to development of animation films' business.