• Journal of Korean Neurosurgical Society
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• v.52 no.4
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• pp.306-311
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• 2012

Objective : A superciliary keyhole approach is an attractive, minimally invasive surgical technique, yet the procedure is limited due to a small cranial opening. Nonetheless, an unruptured supraclinoid internal carotid artery (ICA) aneurysm can be an optimal surgical target of a superciliary approach as it is located in the center of the surgical view and field. Therefore, this study evaluated the feasibility and surgical outcomes of a superciliary keyhole approach for unruptured ICA aneurysms. Methods : The authors report on a consecutive series of patients who underwent a superciliary approach for clipping unruptured ICA aneurysms between January 2007 and February 2012. The data were compared with a historical control group who underwent a pterional approach between January 2003 and December 2006. Results : In the superciliary group, a total of 71 aneurysms were successfully clipped without a residual sac in 70 patients with a mean age of 57 years (range, 37-75 years). The maximum diameter of the aneurysms ranged from 4 mm to 14 mm (mean${\pm}$standard deviation, $6.6{\pm}2.3$ mm). No direct mortality or permanent morbidity was related to the surgery. The superciliary approach demonstrated statistically significant advantages over the pterional approach, including a shorter operative duration (mean, 100 min), no intraoperative blood transfusions, and no postoperative epidural hemorrhages. Conclusion : A superciliary keyhole approach provides a sufficient surgical corridor to clip most unruptured supraclinoid ICA aneurysms in a minimally invasive manner.

• Computers and Concrete
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• v.12 no.2
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• pp.109-129
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• 2013

This work presents an approach to model concrete shrinkage. The goal is to permit the concrete industry's experts to develop independent prediction models based on a reduced number of experimental data. The proposed approach combines fuzzy logic and genetic algorithm to optimize the fuzzy decision-making, thereby reducing data collection time. Such an approach was implemented for an experimental data set related to self-compacting concrete. The obtained prediction model was compared against published experimental data (not used in model development) and well-known shrinkage prediction models. The predicted results were verified by statistical analysis, which confirmed the reliability of the developed model. Although the range of application of the developed model is limited, the genetic-fuzzy approach introduced in this work proved suitable for adjusting the prediction model once additional training data are provided. This can be highly inviting for the concrete industry's experts, since they would be able to fine-tune their models depending on the boundary conditions of their production processes.

• Journal of Mechanical Science and Technology
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• v.19 no.5
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• pp.1087-1094
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• 2005

This paper presents the validity and limitation of the thin-shell approach for the analysis of elastic wave propagation in a pipe with nonviscous liquid. The phase velocities calculated by the thin-shell approach were compared with those calculated by the thick-cylinder approach. In contrast to the case of the empty pipe, where only two modes were obtained and the first mode was calculated in a limited frequency range, the results for the liquid-filled pipe exhibits a large number of modes due to the large number of branches of the apparent liquid mass. Several of the lowest modes of the waves in a liquid-filled pipe were calculated for various pipe thicknesses in a low frequency range. The thin-shell approach was valid for a reasonable range of pipe thicknesses.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.1
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• pp.112-120
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• 2003

This paper reports the development work carried out in respect of a proposed application of Neural Network approach for the Korean Next generation Reactor (KNGR) now referred as APR-1400. The emphasis is on establishing the methodology and the approach to be adopted towards realizing this application in the next generation reactors. Keeping in view the advantages and limitation of Artificial Neural Network Approach, the role of ANN has been limited to plant status or to be more precise plant transient monitoring. The simulation work carried out so far and the results obtained shows that artificial neural network approach caters to the requirements of plant status monitoring and qualifies to be incorporated as a part of proposed operator support systems of the referenced nuclear power plant.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2004.11a
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• pp.176-179
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• 2004

Arthroscopy of the stiff elbow joint is a technically difficult procedure because of the decreased joint space of the elbow joint. even to experienced surgeons. Problems encountered include limited access of instrument to the intra-articular ,pace and an increased risk of cartilage injury in the contracted elbow joint. This study describes a novel transarticular approach for elbow arthroscopy that allow, the safe and effective creation of the proximal medial and lateral portals.

• Research in Mathematical Education
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• v.10 no.1 s.25
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• pp.33-47
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• 2006

Finding good ways to support the further development of mathematically gifted students is a challenge for all mathematics educators. Simply moving able students on more rapidly to the next level of traditional mathematical instruction seems to be a limited approach, while providing supplementary enrichment material or specialized mathematical software requires us to ensure that doing so is truly worthwhile for the students. This paper presents an approach that the author has used with students of diverse capabilities in both technologically advanced and developing nations investigating mathematical ideas using a spreadsheet.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.997-1000
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• 1999

Conventional rule-based approaches have some problems caused by rule maintenance. Also they have some limitations to get the high quality translation results. This paper presents new English-Korean transfer approach that uses patterns and examples on limited domains. The use of patterns and examples can resolve the ambiguities and give high quality of MT Proposed approach can be applied in various NLP related area. Experimental results with a test corpus are discussed.

• Smart Structures and Systems
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• v.5 no.6
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• pp.681-697
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• 2009

Limited, noisy data in vibration testing is a hindrance to the development of structural damage detection. This paper presents a method for optimizing sensor placement and performing damage detection using finite element model updating. Sensitivity analysis of the modal flexibility matrix determines the optimal sensor locations for collecting information on structural damage. The optimal sensor locations require the instrumentation of only a limited number of degrees of freedom. Using noisy modal data from only these limited sensor locations, a method based on model updating and changes in the flexibility matrix successfully determines the location and severity of the imposed damage in numerical simulations. In addition, a steel cantilever beam experiment performed in the laboratory that considered the effects of model error and noise tested the validity of the method. The results show that the proposed approach effectively and robustly detects structural damage using limited, optimal sensor information.

• The Journal of Information Systems
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• v.31 no.4
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• pp.209-232
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• 2022

Purpose In the current environment of online shopping, the cost for consumers to obtain the information they need is decreasing, and the price of products is becoming more transparent, leading to increased price competition among enterprises for similar products. Given the widespread usage of limited-time promotion as a marketing method for enterprises in the context of e-commerce, it is great meaning to study and reveal the internal influence mechanism of limited-time promotion on consumers' impulsive consumption. Design/methodology/approach Based on the S-O-R theory, this study constructs a model of consumers' impulsive consumption in the context of e-commerce from the perspective of perceived price discount, with evoking sense and pleasure as mediating variables and perceived time pressure as moderating variables. Findings The results show that perceived price discount has a significant positive impact on evoking sense and pleasure. Evoking sense has a significant positive impact on pleasure. Both evoking sense and pleasure have a significant positive impact on consumers' impulsive consumption. Meanwhile, perceived time pressure plays a significant moderating role between perceived price discount and evoking sense, between perceived price discount and pleasure, and between evoking sense and consumers' impulsive consumption. Finally, based on the above findings, this study provides effective suggestions for e-commerce participants in the formulation of limited-time promotion strategies.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.88-91
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• 2004

The multiphase flow simulator, MPS, is developed based on the fractional flow approach considering tile fully three phase flow with general initial and boundary condition. Most existing fractional flow-based models are limited to two-phase flow and specific boundary conditions. Although there appears a number of three-phase flow models, they were mostly developed using pressure based approaches. As a result, these models require cumbersome variable-switch techniques to deal with phase appearance and disappearance. The use of fractional flow based approach in MPS makes it unnecessary to use variable-switch to handle the change of phase configurations. Also most existing fractional flow based models consider only specific boundary conditions. However, the present model considers general boundary conditions of most possible and plausible cases which consists of ten cases.