• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.4
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• pp.457-466
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• 2005

In this paper, we propose a wavelet neural network(WNN) based predictive control method for path tracking of mobile robots with multi-input and multi-output. In our control method, we use a WNN as a state predictor which combines the capability of artificial neural networks in learning processes and the capability of wavelet decomposition. A WNN predictor is tuned to minimize errors between the WNN outputs and the states of mobile robot using the gradient descent rule. And control signals, linear velocity and angular velocity, are calculated to minimize the predefined cost function using errors between the reference states and the predicted states. Through a computer simulation for the tracking performance according to varied track, we demonstrate the efficiency and the feasibility of our predictive control system.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.9 s.339
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• pp.71-84
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• 2005

A 'VPN over Intemet' has the benefit of being cost-effective and flexible. However, it has difficulties providing sufficient QoS and adequate transmission capacity for high bandwidth service. Given the increasing demand for high bandwidth Internet and QoS assurances in a 'VPN over Internet', IP/GMPLS based on a control plane combined with a high bandwidth, DWDM optical network is seen as a very favorable anroach for realizing the future 'OVPN over IP/GMPLS over DWDM'. Within this architecture, providing QoS guaranteed multimedia services with a differentiated QoS guaranteed protocol framework with QoS recovery is one of the key issues to implement. Therefore, in this paper, we suggest the entire interoperability procedure of control protocols based on differentiated optical QoS service (DOQOS) classes for providing end-to-end QoS in an 'OVPN over IP/GMPLS over DWDM' architecture.

• Journal of Arbitration Studies
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• v.23 no.1
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• pp.55-84
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• 2013

There should be an arbitration agreement between concerned parties in order to resolve a dispute through arbitration. The arbitration procedures, including the selection of the arbitrator and the adjudicative rights of the arbitrator, are based on the arbitration agreement. In other words, the arbitration procedure and adjudication can be carried out within the boundaries of the arbitration agreement. Traditionally, the Doctrine of Separability of the arbitration agreement has been acknowledged in order to emphasize its importance and to clearly separate it from the contract. Today, when the Doctrine of Separability of the arbitration agreement is well established, overemphasizing this separability could hamper its effectiveness and the autonomy of the parties. Moreover, arbitration agreements in the past were required to be written, clarifying the existence of the agreement and determining the scope of its validity. Further, an arbitration agreement was considered as narrowly as possible. However, since arbitration has become a generalized resolution for disputes, the formal or content requirements should be reconsidered. In terms of validity, the subjective and objective scope should necessarily be extended as a means to resolve disputes related to an arbitration agreement and reduce the resolution cost and duration. Under this perspective, the arbitration theory should now focus on arbitration agreements rather than the place of arbitration. We should break from the nationalistic view, which understands that the arbitration system is a part of the national legal system and that arbitration is allowed solely by permission of the nation. Instead, we should extensively reinterpret the subject of arbitration agreement and its range of effects so that disputes can be resolved between the concerned parties under a single procedure and norm, a necessary step forward. Moreover, in spite of the positive contribution and role of the New York Convention toward the establishment and development of the international arbitration system, there should be an effort to overcome its deterioration. As mentioned in the recommendations regarding the interpretation of the arbitration agreement in the New York Convention in 2006, we should begin by striving to match the Convention as a means of interpretation with the changes of the twenty-first century. Ultimately, we should meet the demands of the new era through amendments to the Convention.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.6
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• pp.698-706
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• 2016

Orthogonal frequency division multiplexing (OFDM) has high peak to power ratio (PAPR). High PAPR makes problems such as signal distortion and circuit cost increasing. To solve the problemsm several PAPR reduction methods have been proposed. However, synchronization and orthogonality in OFDM systems may be a limitation to reduce latency for 5G networks. Generalized frequency division multiplexing (GFDM) is one of the possible solutions for asynchronous and non-orthogonal systems, which are more preferable to reduce the latency. However, multiple subsymbols in GFDM result in more superposition in time domain, GFDM has higher PAPR. Selective mapping (SLM) is one of PAPR reduction techniques in OFDM, which uses phase shift. The PAPR of GFDM SLM is compared to conventional GFDM and OFDM SLM in terms of PAPR reduction enhancement via numerical simulations. In addition, the out-of-band performance is analyzed in the aspect of asynchronous condition interference.

• The KIPS Transactions:PartB
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• v.12B no.4 s.100
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• pp.479-486
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• 2005

The ontology was proposed to construct the logical basis of semantic web. Ontology represents domain knowledge in the formal form and it enables that machine understand domain knowledge and provide appropriate intelligent service for user request. However, the construction and the maintenance of ontology requires large amount of cost and human efforts. This paper proposes an automatic ontology construction method for defining relation between concepts in the documents. The Proposed method works as following steps. First we find concept pairs which compose association rule based on the concepts in domain specific documents. Next, we find pattern that describes the relation between concepts by clustering the context between two concepts composing association rule. Last, find generalized pattern name by clustering the clustered patterns. To verify the proposed method, we extract relation between concepts and evaluate the result using documents set provide by TREC(Text Retrieval Conference). The result shows that proposed method cant provide useful information that describes relation between concepts.

• Quality Improvement in Health Care
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• v.25 no.2
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• pp.44-55
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• 2019

Purpose: To investigate whether changes in Medical Aid (MA) status are associated with unmet need and catastrophic health expenditure (CHE). Methods: Data from the 2010 to 2014 Korea Health Panel (KHP) were used. The impact of changes in annual MA status ('MA to MA,' 'MA to MA Exit,' 'MA Exit to MA,' and 'MA Exit to MA Exit') on unmet need (all-cause and financial) and CHE (10% and 40% of household capacity to pay) were examined using the generalized estimating equation (GEE) model. Analysis was conducted separately for MA type I and II individuals. Results: In 1,164 Medical Aid type I individuals, compared to the 'MA to MA' group, the 'MA to MA Exit' group had increased likelihoods of all-cause and financial unmet need. This group also showed higher likelihoods of CHE at the 10% standard. The 'MA Exit to MA Exit' group showed increased likelihoods at the 10% and 40% CHE standards. In 852 type II recipients, the 'MA to MA Exit' group had higher likelihoods of CHE at the 10% standard. Conclusions: Type 1 MA exit beneficiaries had higher likelihoods of all-cause and financial unmet need, along CHE at the 10% standard. Type I 'MA Exit to MA Exit' beneficiaries also showed higher likelihoods of CHE at the 10% and 40% standards. In type II recipients, MA exit beneficiaries had higher likelihoods of CHE at the 10% standard. The results infer the importance of monitoring MA exit beneficiaries as they may be vulnerable to unmet need and CHE.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1473-1479
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• 2009

This study have been carried out as a part of R&D project to develop a low cost high efficiency combined grain drying & storage system. The design of sweeping auger must meet the various conditions : capacity and dimensions of silo, discharging capacity of auger, operation conditions of auger such as revolution and rotation and density of grains and even the first-in & first-out of grains in the system. Through the experimental observations with the apparatus which enables the direct observation of discharging behavior of grains, the limitations of the performance of existing straight type auger was observed. Generalized mathematical model for the profile of new variable section sweeping auger was obtained, which ensures the uniform descending of grains and also meets various operating conditions. The experimental results with a prototype sweeping auger showed that the mathematical model for the variable section sweeping auger was quitely correct.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.3
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• pp.86-93
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• 2011

Recently, development and application of condition monitoring and diagnostic system for improvement of durability and reliability and reduction of operating cost is generalized in the aircraft propulsion system. Expecially, for reliable operation of the high altitude and a long time and condition monitoring system to identify faults and degradations of its propulsion system should be needed. This work proposed a GUI-based On-line condition monitoring program using LabVIEW by PT6A-67 turboprop engine. The proposed on-line condition program can monitor the real engine performance as well as the trend through precise comparison between performance results calculated by the base performance simulation program and measuring engine performance signals. In the development phase of this monitoring system, a signal generation module is proposed to evaluate the proposed on-line monitoring system.

• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.93-108
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• 2016

Electric vehicle car sharing (EV-sharing) system is noted as an eco-friendly system of transportation in global warming crisis and has been practically implemented in some cities around the world. However, methodologies to find the efficient operation conditions of EV-sharing systems reflecting a typical characteristic 'charging' have not been fully investigated yet. In the paper a generalized model has been developed to identify optimal level of infrastructure for EV-sharing system which provides the optimum operation efficiency under service level constraints. From the simulation analysis based on the developed model the relationships between the operational variables to describe EV-sharing system have been identified and optimal capacity to maximize the operational efficiency have been found. From the analysis of simulation results it has been found that increases in the number of vehicles and chargers improve the service level until certain value beyond which increasing rate and the efficiency have been reduced. From the cost-revenue analysis the optimal numbers of vehicles and chargers have been identified which maximizes the annual operational profit.

• Journal of the Korean Society for Railway
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• v.11 no.6
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• pp.550-561
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• 2008

The purpose of this paper is to propose a new transit assignment model for intercity rail networks. The characteristics of intercity rail are different from that of public transit in urban area. Line selection probability on route section is introduced to include the characteristics of intercity rail into transit assignment model. Network expansion is more simplified by a assumption line selection probability is externally given. The generalized cost is used to decide the volume of each transit line in most of existing transit assignment models. But, many variables have influence on the volume of each line such as time schedule of transit lines, inter-station distance, passengers' income, seasonal variation of demand and regional characteristics. The influence of these variables can be considered to decide the volume of each line by introducing line selection probability on route section. The tests on a small scale network show that the model proposed in this paper is superior to existing models for predicting intercity rail demand. Proposed model is suitable to consider the complicated fare structure of intercity rail and to draw inter-station demand directly as a result of assignment procedure.