• Journal of Advanced Navigation Technology
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• v.19 no.1
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• pp.1-6
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• 2015

Due to the rapid increase in air traffic worldwide, ICAO has replaced the existing navigation equipment with equipment based on satellite navigation. As a part of that work, ICAO was planning to replace conventional takeoff and landing service using ILS with GBAS. Unlike ILS, GBAS which uses precision approach service inducing aircraft to airport and satellite based augmentation system providing precise position information service surrounding airport is capable of providing a required performance by only a system, regardless of the number of systems, and has an advantage that it is possible curved approach. In this paper, fuel reduction of ILS approach procedures and GBAS curved approach procedures is estimated and determined by flight test in Taean Airport.

• East Asian Journal of Business Economics (EAJBE)
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• v.9 no.4
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• pp.93-102
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• 2021

Purpose - Among the various pricing approaches used to set fares for express trains, this study explores a method of utilizing a customer-based pricing approach. The purpose of this study is to figure out how to apply the customer-based pricing approach to fares of new railway services using express trains. Research design, data, and methodology - This study was conducted through a literature review and case studies. In the literature review, we examined three approaches, focusing on the customer-based pricing approach and its application. In the case studies, we show how a customer-based pricing approach can be applied to determining the fares for railway services. Result - Some studies have used a customer-based pricing approach to set railway service rates, adapting the concepts of customer-based pricing such as demand, elasticity, value and willingness to pay. When setting fares of new railway services, it is recommended to use the customer-based approach in conjunction with other pricing approaches. Conclusion - This study demonstrates that a customer-based pricing approach is a promising tool in making decisions on railway fares. By applying a customer-based pricing approach to fares for new railway services using express trains, railway operators can utilize new service rates and increase the profitability of the railway business.

• Industrial Engineering and Management Systems
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• v.15 no.2
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• pp.156-172
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• 2016

Complex and uncertain issues in supply chain result in integrated decision making processes in supply chains. So decentralized (distributed) decision making (DDM) approach is considered as a crucial stage in supply chain planning. In this paper, an uncertain DDM through coordination mechanism is addressed for a multi-product supply chain planning problem. The main concern of this study is comparison of DDM approach with centralized decision making (CDM) approach while some parameters of decision making are assumed to be uncertain. The uncertain DDM problem is modeled through fuzzy mathematical programming in which products' demands are assumed to be uncertain and modeled using fuzzy sets. Moreover, a CDM approach is customized and developed in presence of fuzzy parameters. Both approaches are solved using three fuzzy mathematical optimization methods. Hence, the contribution of this paper can be summarized as follows: 1) proposing a DDM approach for a multi-product supply chain planning problem; 2) Introducing a coordination mechanism in the proposed DDM approach in order to utilize the benefits of a CDM approach while using DDM approach; 3) Modeling the aforementioned problem through fuzzy mathematical programming; 4) Comparing the performance of proposed DDM and a customized uncertain CDM approach on multi-product supply chain planning; 5) Applying three fuzzy mathematical optimization methods in order to address and compare the performance of both DDM and CDM approaches. The results of these fuzzy optimization methods are compared. Computational results illustrate that the proposed DDM approach closely approximates the optimal solutions generated by the CDM approach while the manufacturer's and retailers' decisions are optimized through a coordination mechanism making lasting relationship.

• Journal of Korean Neurosurgical Society
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• v.51 no.6
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• pp.334-337
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• 2012

Objective : The lateral supraorbital (LSO) approach is a modified method of the classic pterional approach and it has advantages of short skin incision and small craniotomy compared with the pterional approach. This study was designed to compare the two approaches in the surgical treatment of unruptured intracranial aneurysms. Methods : We retrospectively reviewed 122 patients with 137 unruptured intracranial aneurysms treated by clipping, from July 2009 to April 2011. Between August 2010 and April 2011, 61 patients were treated by clipping via the lateral supraorbital approach and the same number of patients treated by clipping via the pterional approach were retrospectively enrolled. We analyzed the two groups and compared demographic, radiologic and clinical variables. Results : The mean age of patients in the two groups was 54.6 years (LSO group) and 55.7 years (Pterion group). The mean duration of hospitalization was shorter in the LSO group than in the Pterion group (7.9 days vs. 9.0 days, p=0.125) and the mean operation time was also significantly shorter in the LSO group (117.1 minutes vs. 164.3 minutes, p<0.001). Furthermore, the mean craniotomy area was much smaller in the LSO group (1275.4 $mm^2$ vs. 2858.9 $mm^2$, p<0.001). The two groups showed similar distributions of aneurysm location and postoperative complications. Conclusion : The lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.6 s.107
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• pp.68-81
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• 2005

The styles of contemporary landscape design have diversified since the emergence of Postmodernism in landscape architecture. The diversification was mostly influenced by contemporary fine arts and architecture. This study examines the pluralistic development of Postmodern landscape design through the investigation of the influences from those sister arts. In this point of view, the main approaches of Postmodern landscape design are thought to be classified into three categories;'the formal abstract approach', 'the figurative approach' and 'the new picturesque approach'. The first category of the formal abstract approach was formulated with the concepts and vocabulary of Minimal Art and Installation Art. Its representative icons such as 'point grids' and 'stripes', and the main concepts such as the sense of 'flahess', 'expansion' and 'materiality' are mostly thought to be originated from these art forms. The second category of the figurative approach is characterised by the concepts and vocabulary of Pop Art and New Image Paintings. Its representative icons such as 'map' or 'figurative forms' and main concepts like the sense of 'reality', 'context' and 'symbolism' are mostly thought to be originated from these art forms. The third category of the new picturesque approach was formulated with the concepts and vocabulary of Land Art and Late Deconstructive Architecture. Its representative icons such as 'hybrid', 'layer' and 'fold', and the main concepts such as the sense of 'complexity', 'continuity' and 'reversibility' are thought to be originated from these art forms. The research shows that the main stream of contemporary landscape design seems to be gradually moving toward the second and third approach above, in step with the cultural orientation and the dynamism of contemporary urban life. Therefore, the study focused especially on the new picturesque approach which would be in greater need for coping with the hybrid culture today.

• Journal of Chest Surgery
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• v.50 no.1
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• pp.36-40
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• 2017

Background: Surgical treatment of thoracic outlet syndrome (TOS) is necessary when non-surgical treatments fail. Complications of surgical procedures vary from short-term post-surgical pain to permanent disability. The outcome of TOS surgery is affected by the visibility during the operation. In this study, we have compared the complications arising during the supraclavicular and the transaxillary approaches to determine the appropriate approach for TOS surgery. Methods: In this study, 448 patients with symptoms of TOS were assessed. The male-to-female ratio was approximately 1:4, and the mean age was 34.5 years. Overall, 102 operations were performed, including unilateral, bilateral, and reoperations, and the patients were retrospectively evaluated. Of the 102 patients, 63 underwent the supraclavicular approach, 32 underwent the transaxillary approach, and 7 underwent the transaxillary approach followed by the supraclavicular approach. Complications were evaluated over 24 months. Results: The prevalence of pneumothorax, hemothorax, and vessel injuries in the transaxillary and the supraclavicular approaches was equal. We found more permanent and transient brachial plexus injuries in the case of the transaxillary approach than in the case of the supraclavicular approach, but the difference was not statistically significant. Persistent pain and symptoms were significantly more common in patients who underwent the transaxillary approach (p<0.05). Conclusion: The supraclavicular approach seems to be the more effective technique of the two because it offers the surgeon better access to the brachial plexus and a direct view. This approach for a TOS operation offers a better surgical outcome and lower reoperation rates than the transaxillary method. Our results showed the supraclavicular approach to be the preferred method for TOS operations.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 1999.10a
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• pp.337-346
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• 1999

In this paper, we propose the rough set approach to extract trading rules able to discriminate between bullish and bearish markets in stock market. The rough set approach is very valuable to extract trading rules. First, it does not make any assumption about the distribution of the data. Second, it not only handles noise well, but also eliminates irrelevant factors. In addition, the rough set approach appropriate for detecting stock market timing because this approach does not generate the signal for trade when the pattern of market is uncertain. The experimental results are encouraging and prove the usefulness of the rough set approach for stock market analysis with respect to profitability.

• The Journal of Korea Robotics Society
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• v.4 no.2
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• pp.88-96
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• 2009

In this paper, we present a linear controller for attitude of aircraft. We use a rotational matrix in one approach and a quaternion in the other approach. We also find some interesting mathematical properties concerning a symmetric rotational matrix and we use these properties to analyze the stability of the proposed control law. We find that the quaternion approach is better than rotational matrix approach because there exists no singular region problem in quaternion approach. On the other hand, singular region problem may happens in rotational matrix approach. The controller structure of the quaternion is also very simple compared with the one proposed by using a rotational matrix approach. We make use Matlab Simulink to simulate and illustrate the theoretical claims. The graphic animation program is developed based on Open-GL for the computer simulation of the proposed control algorithm.

• Structural Engineering and Mechanics
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• v.7 no.2
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• pp.127-145
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• 1999

This paper deals with the development of an approach for evaluating the squash load and rigidity of unprotected concrete filled steel columns at elevated temperatures. The current approach of evaluating these properties is reviewed. It is shown that with a non-uniform temperature distribution, over the composite cross-section, the calculations for the squash load and rigidity are tedious in the current method. A simplified approach is proposed to evaluate the temperature distribution, squash load, and rigidity of composite columns. This approach is based on the model in Eurocode 4 and can conveniently be used to calculate the resistance to axial compression of a concrete filled steel column for any fire resistance time. The accuracy of the proposed approach is assessed by comparing the predicted strengths against the results of fire tests on concrete filled circular and square steel columns. The applicability of the proposed approach to a design situation is illustrated through a numerical example.

• Industrial Engineering and Management Systems
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• v.6 no.1
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• pp.28-39
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• 2007

The issue of customer-centric enterprise focusing on realizing customer needs has recently received considerable attention in the corporate world. However, little research has yet been reported on developing Information Systems (IS) supporting the customer-centric enterprises. This research proposes an integrated approach of IS development that supports organizations aiming to become customer-centric enterprises using various customer profiles. In this paper, we propose an integrated approach unifying goal modeling, business process modeling, and information systems modeling. The approach is expected to be seamlessly linked with the object-oriented systems development approach. Finally, we apply this approach to the real case of a securities company in Japan.