• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.81-88
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• 2008

It is important to study the energy efficient MAC protocol in sensor networks. We propose a new protocol named as ELM?MAC (Energy efficient Link Management MAC) to increase energy efficiency in sensor networks. ELM-MAC protocol operates, uses, and manages the optimized transmission power level to increase energy efficiency in MAC layer. It includes mechanism that uses the adaptive method in change of surround environment for guarantee of link quality. In this paper we implement ELM-MAC and evaluate its performance.

• Journal of Advanced Navigation Technology
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• v.13 no.3
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• pp.344-350
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• 2009

In this paper, interference effect given from non-geostationary orbit link into geostationary orbit link is analyzed by BER performance. To analyze the interference effect with the angle between satellites, the angular separation is changed from $1^{\circ}$ to $8^{\circ}$, and the number of the satellite is also changed from 1 to 4 for analyzing it. From the results, the interference effect into the geostationary orbit service from non-geostationary orbit link is more increased according to the angular separation that is decreased. Especially, the small angle gives more interference effects to the geostationary orbit link. Furthermore, more number of interfering satellites gives more interference effect to the geostationary orbit link. However, the angle between the interference orbit and geostationary orbit gives more effect to the system performance then the number of the interference orbit.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.spc
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• pp.61-67
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• 2023

Special equipment used for snow removal is only used in the winter and must be moved into storage during non-winter seasons. However, when moving heavy equipment using a forklift within a limited space, safety accidents may occur due to deformation and damage due to the worker's limited visibility and excessive loading of heavy objects. In this study, the scissors boom of the developed heavy load transporter was conducted in two cases: link structural analysis and position-based structural analysis. In detail, the link structural analysis covers four cases of stress and safety factor according to material and thickness to optimize the specifications of the material selected during development, and the structural analysis according to position covers two cases before and after the lift, when maximum stress concentration is achieved. Safety was evaluated through finite element analysis. As a result of the study, when manufacturing a scissors boom type heavy load transporter that can withstand a load of 10 tons, the link showed safety at SS400 4.5mm or higher, and reinforcement is needed in the upper and lower structures, so it is judged to be useful in applying materials according to the load.

• Journal of Industrial Convergence
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• v.6 no.2
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• pp.93-108
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• 2008

The central contribution of this paper is a model that integrates and extends two established frameworks in the management literature to propose a theoretical link between two previously disconnected constructs: transformational and transactional leadership and organizational learning.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.6
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• pp.1208-1216
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• 2015

In this paper, we use WiMedia WLP-based networks to meet the demand for IT services of a ship. If a mobile node moves to a congested base station of a new subnetwork, we will propose a scheme for improving performance of radio link of existing communicating mobile nodes. An old base station denotes packets stored during a handover. And, a proposed buffer management determines to discard the buffered packets in accordance with congestion degree at the congested new base station. Simulation results show that the proposed buffer management scheme improves link utilization in congested wireless links.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.103-113
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• 1985

This is the first part of the four-part paper describing the development of a packet-switched computer network named the KORNET In this paper, we present the overview of the KORNET, and discuss various aspects on the development of the netwo management center (NMC). The NMC acts as a nerve center of the network, performing such functions as network monitoring, subscriber and network management and routing manage-ment using operator dialogues. In the implementation of the NMC, we have developed various application softwares that include operator interface, primary/srcondary pan, session layer and packet level adaptor. As for packet, link and physical level protocols, we have modified the XODIAC X.25 originally developed by Data General, Inc. All the net-work protocols we have developed comply completely with the CCITT recommendations.

• Journal of Distribution Science
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• v.20 no.10
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• pp.11-17
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• 2022

Purpose: This research aims to find the link between public service Distribution and individual job performance in the provincial municipality. Research design, data, and methodology: This is a quantitative approach study with a non-experimental and correlational design. The sample consisted of 140 employees appointed and hired by the provincial municipality of Huaraz. For data collection, Two questionnaires with an ordinal Likert-type scale and the Rho Spearman correlation coefficient were used to assess the link between the research variables., For Analysis: two questionnaires with an ordinal Likert-type scale and the Rho Spearman correlation coefficient were used to determine the connection between the research variables. Results: It was determined that both variables have a high degree of correlation (0.725), indicating a direct and significant relationship between the Distribution of public service and skill performance in the provincial municipality (0.614). Conclusion: Finally, this allows us to conclude that the institutional context is essential; that is, there is a significant correlation between the PSM and contextual performance in the provincial municipality of Huaraz, which has a Rho Spearman value of 0.723.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.303-309
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• 2013

This paper analyzed about operation environment and policy for US military tactical communication, and security policy and transmission performance of tactical link. It is presented operation communication message and framework, which is supported semi automated force, SINCGARS specification of link layer in operation environment, and analyzed COMSEC policy and application layer security in tactical security policy. Also it analyzed in respect to transmission performance and crypto synchronization detection. Security policy of tactical link and COMSEC is analyzed in respect of crypto device such as AFKDMS, AKMS, RBECS, KIV-7/HSB.

• Journal of Korean Society of Transportation
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• v.13 no.4
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• pp.79-103
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• 1995

The elasticity of a model is considered most important. Without showing the proper elasticity any model cannot provide useful information for decision making. This paper demonstrates a macro model which can generate dynamic transport informations every 15 minutes. Without the Wardrop principles and the monotonicity assumptions for the link travel time and link volume relationship, the basic elements of this new modeling approache are composed of link density simulation, stochastic incremental route choice, departure time choice, destination choice and mode choice. The elasticity of the proposed model is examined based on elasticity equations and simulation results. Also the transferability from a mega city like Seoul to a big city like Daejon is demonstrated for the choice model. The issues centering around the dynamic relations among density(k), speed(u), and flow rate(v) are also discussed for the modeling of highly congested situations.

• Journal of Digital Contents Society
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• v.3 no.2
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• pp.143-152
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• 2002

In this paper, we present the general interface, label-switched path structure and link bundling in GMPLS to improve the scalability. The LMP protocol is also introduced to efficiently manage the internal link, and the signaling protocol, hierarchical path setup, hi-directional LSP setup and suggested label method are presented. Finally, the techniques of protection and restoration are presented. In specific, various applicable restoration techniques in GMPLS are discussed.