• Journal of Institute of Control, Robotics and Systems
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• v.6 no.11
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• pp.943-954
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• 2000

Fieldbus is the lowest level industrial network in the communication hierarchy of factory automation and distributed process control systems. Data generated from field devices are largely divided into three categories : time-critical, periodic and time-available data. Because these data share one fieldbus medium, it needs a method that allocates these data to the bandwidth-limited fieldbus medium. This paper introduces an implementation method of bandwidth allocation scheme on PROFIBUS. In order to implement bandwidth allocation scheme on PROFIBUS, the following functions need to be supplemented on the FDL(Fieldbus Datalink Layer) protocol: (i) separation of medium bandwidth into periodic and non-periodic intervals, (ii) synchronization of node timers over a local link. In order to examine the validity of bandwidth allocation scheme on PROFIBUS, this paper develops an experimental model of a network system. The results obtained from the experimental model show that the bandwidth allocation scheme satisfies the performance requirement of time-critical, periodic and time-available data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.10
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• pp.60-66
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• 2004

Redundant thrusters are generally adopted to satellite designs for a highly reliable attitude control system. So efficient redundancy management is required to take advantage of these redundant thrusters. In this paper, control allocation method is proposed as a method for controlling redundant thrusters. Control allocation is a method to calculate optimal distribution on redundant controls for realizing desired forces/torques. It is shown that a control allocation problem for redundant thrusters is formulated as a linear programming problem which minimizes fuel consumptions with thrusters, constraints. We also show that the proposed method is more efficient than an existing method by numerical examples.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.1
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• pp.16-22
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• 2015

This paper proposes a power allocation method for multiple node beamforming with uniform circular array antennas to increase SIR of nodes in wireless mesh network. The proposed method calculates beamforming power allocation vectors that maximizes SIR satisfied with power constraint of HPA. The simulation results demonstrate the proposed method achieves the enhanced SIR of nodes than that of beamforming method.

• Journal of Digital Convergence
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• v.10 no.8
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• pp.91-96
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• 2012

The purpose of this study is to examine the rationality for public organizations' cost allocation method through the case of special post offices. The proper use of allocation method is crucial to promote and nurture the public organization sector. On that note, this paper presents how to apply the proper estimation method. The cost allocation method is to split the total expense into appropriate services and departments. Using the basic expense rate and the standard depreciation rate and area at each post office, the total cost is calculated into the cost per person and area. As a result, the correct cost can be assigned through allocation per according service unit.

• Journal of Korean Library and Information Science Society
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• v.46 no.4
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• pp.191-205
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• 2015

As the first step in developing the optimal co-authorship allocation method, this study investigated the co-authorship allocation standards of Korean Universities on journal publications. The study compared the standards of 27 Korean universities with Library and Information Science (LIS) departments, and analyzed author rankings generated by applying inflated, fractional, harmonic, and university standard method of co-authorship allocation to 189 Korean LIS faculty publications from 2001 to 2014. The university standards most similar to the standard co-authorship allocation method in bibliometrics(i.e. Vinkler) were those whose co-author credits summed up to 1. However, the university standards differed from Vinkler's in allocating author credits based on primary and secondary author classification instead of allocation based on author ranks. The statistical analysis of author rankings showed that the harmonic method was most similar to the university standards. However, the correlation between the university standards whose co-author credits summed up to greater than 1 and harmonic method was lower. The study results also suggested that middle-level authors are most sensitive to co-authorship allocation methods. However, even the most generous university standards of co-authorship allocation still penalizes collaborative research by reducing each co-authors credit below those of single authors. Follow-up studies will be needed to investigate the optimal method of co-authorship credit allocation.

• Journal of Korean Society for Quality Management
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• v.28 no.3
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• pp.91-103
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• 2000

It is very important to rationally allocate manufacturing processes because customer's needs are being various, and product life cycle in the market Is being shortened. The process allocation is needed before making process control plan and is mostly being done by the field experience or intuition of machine operator, process engineer and/or maintenance technician. Therefore, a modified allocation method using the process variation is proposed. This paper presents the result of comparative studies between current method and the proposed one.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.980-981
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• 2013

This paper introduces a new allocation method of unused bandwidth for TWDM PON and explains the performance evaluation results. Using computer simulations, we compare the mean delay and the frame delay variance of the proposed method with those of the existing method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.978-979
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• 2013

This paper introduces a dynamic wavelength and bandwidth allocation method for TWDM PON and describes the performance evaluation results. Using computer simulations, we compare the frame delay variance and the frame loss rate of the introduced method with those of the existing method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1471-1488
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• 2018

Interference mitigation is a significant issue in the cognitive heterogeneous networks, this paper studied how to reduce the interference to macrocell users (MU) and improve system throughput. Establish the interference model with imperfect spectrum sensing by analyzing the source of interference complexity. Based on the user topology, the optimize problem was built to maximize the downlink throughput under given interference constraint and the total power constraint. We decompose the resource allocation problem into subcarrier allocation and power allocation. In the subcarrier assignment step, the allocated number of subcarriers satisfies the requirement of the femtocell users (FU).Then, we designed the power allocation algorithm based on the Lagrange multiplier method and the improved water filling method. Simulation results and performance analyses show that the proposed algorithm causes less interference to MU than the algorithm without considering imperfect spectrum sensing, and the system achieves better throughput performance.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.131-134
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• 2009

The MOST network, which is a network for vehicle infotainment network, requires efficient channel allocation to provide multimedia service effectively. Though there is a study on channel allocation according to network traffic as studies on channel allocation for MOST network, there have scarcely been studies on channel allocation according to bandwidth of multimedia for transferring. Therefore, in this paper, we propose the channel allocation method which calculates the number of channels by analyzing multimedia data for transferring and assigns the optimal number of channels for the given data. The proposed method reduces wasting of channels by optimally allocating channels and prevents initializing network due to change of Boundary Descriptor.