• Journal of IKEEE
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• v.19 no.2
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• pp.142-147
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• 2015

In this paper, a Kalman filter-based sensor fusion filter that measures posture by calibrating and combining information obtained from acceleration and gyro sensors was proposed. Recent advancements in sensor network technology have required sensor fusion technology. In the proposed approach, the nonlinear system model of the filter is converted to a linear system model through a Jacobian matrix operation, and the measurement value predicted via Euler integration. The proposed filter was implemented at an operating frequency of 74 MHz using a Virtex-6 FPGA Board from Xilinx Inc. Further, the accuracy and reliability of the measured posture were validated by comparing the values obtained using the implemented filters with those from existing filters.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.561-579
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• 2014

This research estimates the necessity of a better governance plan on the purpose of fulfillment energy recovery by building resource recycling system for biomass resources and waste resources that derive from agricultural and mountain village areas. The utilization of new renewable energy technology which uses waste and biomass sources diverse as variety of resources, collecting method, operator etc. and is structurally complicated the formation of policy is also very difficult. There is failure because of the problems which occurs from the policy led by government. Biomass Town Development Project should be made through the central government and the local government integrated support system and should be formed a consultative group in order to process the project mutually with these two department including the experts from the related areas. This consultative group, while government organizations carry out the hub function of strategic knowledge management, should carry out the control tower function to be able to be net working transfer the information with the cooperation of private and government so vitalize the communication area among the related actors. And to be able to increase the participation rate of the local people the consistent and various educations should be given so a smooth business promotion progress will be desired through the change of perception and coactive participation of people.

• Journal of Hydrospace Technology
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• v.1 no.1
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• pp.29-40
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• 1995

This paper describes the procedure to predict steady and unsteady performances of a contrarotating propeller(CRP) by a mixed formulation of the boundary value problem(BVP) far the flow around a CRP. The blade BVP is treated by a classical vortex lattice method, whereas the hub BVP is solved by a potential-based panel method. Blades and trailing wakes are represented by a vortex and/or source lattice system, and hubs are represented by normal dipole and source distributions. Both forward and aft propellers are solved simultaneously, thus treating the interaction effect without iteration. The unsteady performance is computed directly in time domain. The new numerical procedure requires a large amount of storage and computing time, which is however no longer a limit in a modern computer system. Sample computations show that the steady performance compares very well with the experiments. The predicted unsteady behavior shows that the dominant harmonics of the total forces are multiples of not only the number of blades of the forward and aft propellers but also the product of both blade numbers. The magnitude of the latter harmonics, present also in uniform oncoming flow, may reach abort 50% of the mean torque for the aft propeller, which in turn may cause a serious vibration problem in the complicated contrarotating shafting system.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.758-766
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• 2023

Multi-copter of unmanned aerial vehicle (UAV) was initially developed as strategic technology in the only military field, but it is developing into an industrial field with a wide range of applications in the civil sector based on the development and convergence of aviation technology and information and communication technology. Currently, the degree of utilization of multi-copter is increasing in various industries for the purpose of performing classic tactical missions, logistics transportation, farm management, internet supply, video filming, weather management, life-saving, etc, and active technology development responding to market demand. Existing commercial multi-copter mainly use an electric energy propulsion system consisting of an electric battery and a brushless direct current (BLDC) motor. It is the limitations for usage in the flying time (up to 20 minutes) and payload (less than 20 kg). this study aims to overcome these limitations and expand the commercialization of engine-powered multi-copter of UAV in various industries in the futures.

• International Journal of Computer Science & Network Security
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• v.24 no.5
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• pp.191-197
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• 2024

Software reuse gives the meaning for rapid software development and the quality of the software. Most of the Java components/libraries open-source are available only in Java Archive (JAR) file format. When a software design enters into the development process, the developer needs to select necessary JAR files manually via analyzing the given software architecture and related JAR files. This paper proposes an automated approach, JarBot, to suggest all the necessary JAR files for given software architecture in the development process. All related JAR files will be downloaded from the internet based on the extracted information from the given software architecture (class diagram). Class names, method names, and attribute names will be extracted from the downloaded JAR files and matched with the information extracted from the given software architecture to identify the most relevant JAR files. For the result and evaluation of the proposed system, 05 software design was developed for 05 well-completed software project from GitHub. The proposed system suggested more than 95% of the JAR files among expected JAR files for the given 05 software design. The result indicated that the proposed system is suggesting almost all the necessary JAR files.

• Journal of Navigation and Port Research
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• v.40 no.1
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• pp.43-50
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• 2016

Amid of the logistics hub center competition is going to intensifying between the world major port, it is essential to pre-occupied the base in the logistics hub world take advantage of advanced technology of logistics equipment than other ports. In existing container terminal, when container moves the terminal use the omnidirectional and directional antenna in order to exchange data information on the basis of 802.11 wireless network system. Case of loading height of exceeding, the blind sport will occur and a limited frequency channel can't help using in the area. A limited frequency channel usage and nested areas happen to use the closed terminal, it has a great influence to operate the terminal working. In this paper, LTE network is configured provided by the specified company ('L' Corp,.Ltd) and terminal data extracted through LBO (Local Breakout) in the cell site which is configured directly with container terminal operation server. Using this method, container terminal yard equipment operate without overlapping arises with uninterrupted data presented for ways to efficiently. I would suggest both the existing wireless AP LAN configuration of container terminal and new LTE system and applied to the real yard operating devices situations. Through these methods presented comparative the existing network traffic with new constructed LTE configuration. I admired to suggest that wireless network LTE introduction is fundamental factors to get rid of the blind spot, the problem of limited frequency channel and overlapping arises. These essential points can be a continual improving terminal services and more efficient terminal operational management.

• Maritime Security
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• v.7 no.1
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• pp.1-29
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• 2023

For the last 70 years, the U.S.-led bilateral security system, or "Hub-and-Spokes" system, has been applied to Northeast Asia, and the system has been successfully settled in terms of stability and economic achievements of the region. Given the increasing complexity of the security environment of East Asia, it is plausible to consider the possibility of a security system shift from bilateral alliances to collective security. In order to analyze the driver of collective security system, this study developed three factors of formation and development of collective security system - main threat, intensity of the threat, and confidence among countries in the system - by reviewing international political theories related to security cooperation. Comparing the formation, development, and achievements of NATO and SEATO, the study figures out that the existence of the main threat, the high intensity of the threat, and the strong confidence among countries in the security system are the primary drivers for a successful collective security system. Based on the result, the study also analyzed the possibility of a security system shift in East Asia. Considering contemporary international conflicts such as U.S.-China strategic competition, Russia-Ukraine War, and growing threats posed by North Korean nuclear and missiles, the study anticipates that the necessity of a collective security system that will replace the current security system of the region would arise. Still, although some issues between countries should be overcome, the growing intensity of the threats will promote cooperation among countries by improving their confidence.

• International Commerce and Information Review
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• v.11 no.3
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• pp.47-71
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• 2009

In order to implement e-trade infrastructure through the radical innovation of trade process, e-trade platform which is called 'uTradehub' has been developed for three years. After pilot operation of this platform in 2007, the formal service of e-trade such as logistics, customs and foreign exchanges had been provided in 2008. However, the usage of e-Trade platform is not the level of users' satisfaction because trade-related communities have not actively participated into e-trade platform and several functions with users requirements are necessary to develop additionally. In this regard, there are strong demands to suggest some strategies for application and usage proliferation of e-trade platform. Therefore, this paper would like to evaluate the current status of e-trade platform service and usage by the theoretical consideration of preceding researches and practical analysis of statistical data. Then, it will explore several service improvement ideas in terms of system supplementation and integration, electronic documents standardization, radical change of using fee, global connection, user oriented education and advertisement.

• Genomics & Informatics
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• v.18 no.2
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• pp.13.1-13.6
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• 2020

The prototype version of the full-text corpus of Genomics & Informatics has recently been archived in a GitHub repository. The full-text publications of volumes 10 through 17 are also directly downloadable from PubMed Central (PMC) as XML files. During the Biomedical Linked Annotation Hackathon 6 (BLAH6), we experimented with converting, annotating, and updating 301 PMC full-text articles of Genomics & Informatics using PubAnnotation, a system that provides a convenient way to add PMC publications based on PMCID. Thus, this review aims to provide a tutorial overview of practicing the iterative task of named entity recognition with the PubAnnotation/PubDictionaries/TextAE ecosystem. We also describe developing a conversion tool between the Genia tagger output and the JSON format of PubAnnotation during the hackathon.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1371-1381
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• 1995

A novel hybrid control scheme to actively control the endpoint position of a very flexible single-link manipulator is proposed. The control scheme consists of a motor mounted at the beam hub and a piezofilm actuator bonded to the surface of the flexible link. The control torque of the motor to produce a desired motion is firstly determined by employing the sliding mode control theory on the equation of motion of the rigid link having the same mass as that of the proposed flexible link. The torque is then applied to the flexible manipulator in order to activate the commanded motion. During the motion, undesirable oscillation is actively suppressed by applying a feedback control voltage to the piezofilm actuator. Consequently, the imposed desired position is accomplished. In order to demonstrate high control performances accrued from the proposed method, computer simulations are undertaken by treating both regulating and tracking control problems.