• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.165-171
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• 2021

Vehicular Ad hoc Network (VANET) is an extension paradigm of moving vehicles to communicate with wireless transmission devices within a certain geographical limit without any fixed infrastructure. The vehicles have most important participation in this model is usually positioned quite dimly within the certain radio range. Fuzzy based multi-hop broadcast protocol is better than conventional message dissemination techniques in high-mobility VANETs, is proposed in this research work. Generally, in a transmission range the existing number of nodes is obstacle for rebroadcasting that can be improved by reducing number of intermediate forwarding points. The proposed protocol stresses on transmission of emergency message projection by utilization subset of surrounding nodes with consideration of three metrics: inter-vehicle distance, node density and signal strength. The proposed protocol is fuzzy MHB. The method assessment is accomplished in OMNeT++, SUMO and MATLAB environment to prove the efficiency of it.

• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.25-35
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• 2016

This paper is to classify subregions of Yeongnam region, to realize their core area, and to provide the basis on studying inherent cultural characteristics in Yeongnam region. To do so, I made a overlay human factors of administrative district and dialect with physical factors of drainage basin and climate area. The limit of subregion is the range of possessing environmental factors similar to provincial center. The parcels possessing a equivalent combination of environmental factors are 27, the size of parcel is various from one-city/county to six-city/county. These parcels are classified to six subregions(Andong, Sangju, Kyeongju, Daegu, Kimhae, Jinju). The boundary of subregion is high mountains and large river which are obstacle to communication between subregions, and in case of little obstacle exists transitional zone.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.3
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• pp.65-72
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• 2011

Extensive computer simulations to account for the randomness in the process of seismic demand estimation have been a serious obstacle to the adoption of probabilistic performance assessments for the decision of applying seismic intervention schemes. In this study, a method for rapid fragility assessments based on a response database and the fragility contour method are presented. By the comparison of response contours in different formats, it is shown that representing maximum responses in ductility demand is better for the investigation of the effect of structural parameter changes on seismic demands than representations in absolute values. The presented fragility contour enables designers to practically investigate the probabilistic performance level of every possible retrofit option in a convenient manner using visualized data sets. This example demonstrates the extreme efficiency of the proposed approach in performing fragility assessments and successful application to the seismic retrofit strategies based on limit state probabilities.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.491-494
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• 2002

The real-time industrial network often referred to as fieldbus, is an important element for building automated manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices such as sensors, actuators, and controllers. numerous standard organizations and vendors have developed various fieldbus protocols such as Profibus, WorldFIP and Foundation Fieldbus. However, the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. In order to solve these problems, the computer network technology, especially Ethernet (IEEE 802.3), is being adopted lo the industrial environment. The crucial technical obstacle for Ethernet is that its non-deterministic behavior makes it inadequate for industrial applications where real-time data such as control command and alarm signal hale to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet for industrial comm unications.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.115-122
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• 2008

Mostly used sensors have wired powering and two-way cable systems. It is difficult to employ wired sensor network in ubiquitous era because of a number of sensors and cables. Therefore, sensor networks move from wired systems to wireless systems for the future. However, the power source is a critical obstacle for wireless sensornodes. This research represents the new power source which supplies energy sensor node, maintains over 10 years, and thus replaces batteries with limit of lifetime. The system with piezo materials scavenges extra energies such as vibration and acceleration from the environment. Then it converts the scavenged mechanical energy to electrical energy for powering a sensor, a controller and a circuit for regulating voltage and transmitting sensor value. This study explains the properties of piezo material through theoretical analysis and experiments, and demonstrates powering sensor and transmitting data with stored energy (35mJ) for 14 sec. The developed system provides a solution to overcome the critical problem of making up wireless sensor networks.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.1
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• pp.90-98
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• 2003

The real-time industrial network, often referred to as fieldbus, is an important element for building automated manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices, numerous fieldbus protocols have been announced. But the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. Therefore, as an alternative to fieldbus, the computer network technology, especially Ethernet (IEEE 802.3), is being adapted to the industrial environment. However, the crucial technical obstacle for Ethernet is its non-deterministic behavior that makes it inadequate for industrial applications where real-time data have to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet for industrial communications. More specifically, this paper presents an analytical and experimental performance evaluation of the switched Ethernet and a case study about networked control system.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.8
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• pp.718-725
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• 2004

The real-time industrial network, often referred to as fieldbus, is an important element for intelligent manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices, numerous fieldbus protocols have been announced. But, the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. Therefore, as an alternative to fieldbus, the computer network technology, especially Ethernet (IEEE 802.3), is being adapted to the industrial environment. However, the crucial technical obstacle for Ethernet is its non-deterministic behavior that makes it inadequate for industrial applications where real-time data have to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet with cascade structure for industrial communications. More specifically, this paper presents an analytical performance evaluation of switched Ethernet with cascade structure, and a case study about networked control system.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.9
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• pp.946-951
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• 2009

The small multi-jointed robots for most education are developed with the way of firmware. But the firmware may be very difficult to develop as gradually increasing throughputs and control routines. Due to limit of firmware we try to use on RTOS, but hard to adapt on the small multi-jointed robots. It would be hard to install RTOS into the small multi-jointed robots because of the size capacity of RTOS, and lack of libraries for control of the particular hardware. Moreover, even its RTOS with many functions causes its to make overheads scheduling, TCB (Task Control Block), and task states. Also to keep maintenance of RTOS, it is composed of components for the whole structure of my proposed RTOS. Additionally, We provided with libraries of servo motor and sensor control and developed RMS (Rate Montonic scheduler) to handle tasks on real time and reduce overheads. Therefore, It is possible to work the fixed priority and task preemptive way. We show one example of the multi-jointed robot installed with my proposed RTOS, which shows to obstacle avoidance and climbing up the slope.

• KDI Journal of Economic Policy
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• v.45 no.2
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• pp.1-20
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• 2023

Carbon pricing is in the spotlight as an economically efficient policy to limit global warming and reduce greenhouse gas emissions. We examine how policymakers can improve social acceptance of a carbon tax, which is the main obstacle in implementing the policy. We conduct a survey experiment to analyze this topic and adopt two different interventions focusing on the use of revenue from a carbon tax and types of information to be provided. Regarding revenue use, we consider 1) tax reductions, 2) lump-sum transfers, and 3) green project investments. For information types, we focus on 1) the economic value of a carbon tax, and 2) the environmental value of a carbon tax. We find that lump-sum transfers have negative impacts on social acceptance of a carbon tax. For those who perceive climate change as a serious issue, moreover, both lump-sum transfers and tax reductions have negative impacts on acceptability. Regardless of the type of information provided, on the other hand, the social acceptance of a carbon tax is increased after the provision of information. Furthermore, the impact of information provision on the social acceptance interacts with the revenue use impacts. When the revenue use and the type of information are consistent with the aim of the policy, the effects of these strategies can be amplified.

• Archives of design research
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• v.17 no.2
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• pp.279-288
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• 2004

Corporate design activities have expanded from being exclusive and passive responsibilities to active participation in planning, marketing, technology and corporate brand image differentiation for successful business. Thus the communications between designers and other functions come to include critical decision making, information sharing, and objective reasoning. Given that design activities now have to involve various functions in product development, the styling-related design process, which is still developed by designer's intuition and experience, poses as an obstacle not just between various functions involved, but even within the design function. To overcome this obstacle and to lead more effective design decision process, a means for product form development assessment and management is necessary. This research proposes a foundation for managing and assessing product form based on the hypothesis and demonstration of discovering a system of formative factor and order a product form expresses that can be shared as an objective and logical system. As a result of this demonstration, the form as a unique visual expression and the factors related to the form and its co-relationship are examined. The factors are called formative parameters and the system is named as the product form alignment method. Based on the logic derived from the system, the process for developing an image that aligns with the predefined goal is explained. The method defines a balance between a designer's intuitive creativity and the extracted logic, which can act as a basis for designers to share design language among themselves and for communication between design and other functions. Based on this system, designers are able to align design work with the set goal, and focus and limit the range of form development, which is anticipated to result in lead-time reduction and minimizing unnecessary obstacles and mistakes.