• Survey Research
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• v.5 no.1
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• pp.93-101
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• 2004

In business survey, cut-off sampling is usual, The contribution from cut-off part of the population is at least small in comparison with the remaining population. In this case, part of the target population is excluded from the selection and parameter estimations are only based on Take-all and Take-some stratum. It may be tempting not to use resources on enterprises that contribute little to the overall results of the survey. And this reduces the response burden for these small enterprises. But, the size of cut-off stratum has been increased as a way to manage reduced budgets. This leads to additional bias. In this study, the population have been separated as three stratum, cut -off, take-some, take-all, and we will estimate cut-off part using auxiliary variable.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.7
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• pp.418-423
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• 2000

The fiber Fabry-Perot interferometric(FFPI) sensor is well known in the field of industrial diagnosis due to its outstanding properties such as tiny size, simple and rugged structure, and easy interrogation. As other fiber interferometric sensors, it also suffers from ambiguous output caused by highly periodic feature in its optical transfer function. In most cases, the ambiguity leads to relatively short dynamic operating range and long processing time during power-on reset, which limits its application to some specific fields requiring very high resolution. In this paper a method based on double sensing scheme was proposed to overcome the above difficulty. By employing a fringe selection auxiliary FFPI sensor the original FFPI sensor can identify its true position on the phase domain. The performance test with 10mm FFPI sensor and a thermocouple temperature sensor for reference shows wide dynamic range 0-900$\ell$ keeping a reasonable resolution of 0.1$\ell$ over the entire range.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.1
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• pp.151-163
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• 2013

Recently the attention on digital hologram that is regarded as to be the final goal of the 3-dimensional video technology has been increased. Digital hologram is calculated by modeling the interference phenomenon between an object wave and a reference wave. The modeling for digital holograms is called by computer generated hologram (CGH) Generally, CGH requires a very large amount of calculation. So if holograms are generated in real time, high-speed method should be needed. In this paper, we analyzed CGH equation, optimized it for mapping general purpose graphic processing unit (GPGPU), and proposed a optimized CGH calculation technique for GPGPU by resource allocation and various experiments which include block size changing, memory selection, and hologram tiling. The implemented results showed that a digital hologram that has $1,024{\times}1,024$ resolution can be generated during approximately 24ms, using 1K point clouds. In the experiment, we used two GTX 580 GPGPU of nVidia Inc.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.2
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• pp.258-264
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• 2010

Various kinds of ballast water treatment systems (BWTS) have been developed corresponding to reinforced IMO rules for marine environment. Some of them got the certificate of IMO and others are waiting for it. Selection of optimum BWTS is very important. Optimum BWTS means not only functional requirements but also economic efficiency. This paper presents economic analysis model for optimum BWTS according to ship type and size. In this study 10 kinds of BWTS whose initial installation cost and maintenance cost are known are analyzed based on present worth method. It is assumed that all BWTS satisfy minimum functional requirements and we need to consider different economical efficiency. Through the economic analysis we could select optimum BWTS.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.92-99
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• 2012

According to the scale of mobile applications has been expanded, the high coupled application combined mobile and web service are growing. The growth of mobile application's size means that predicting design for variability should be involved. If mobile application's change is occurred, application should be reinstalled totally. However this reinstallation can raise side-effects in case of high-coupling application. Therefore, this paper proposes a technique of customization for changing web service protocol as the mobile applications are connected with web service in android platform. Proposed protocol customization technique is consist of selection and plug-in technique.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.2
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• pp.123-150
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• 2004

The purpose of this study is to prove that the approprlate fit between service failure and recovery strategy can effciently maximize customer satisfaction and behavioral intention, by using prepared scenario through comprehensive approach concerning how the expectation level about service recovery has influences on perceived fairness, satisfaction and behavioral intention of servlce recovery based upon size in case of service failure. This study has been conducted by way of selection of filling-up type questionnaires for customers themselves who have experience in service failure out of customers who can easily visit family and hotel restaurants, that is, domestic restaurants in Seoul area, June ~ August 2004, by setting factorial design of 2(control, severeness) ${\times}$ 3(distributive fairness, procedural fairness, mutual relational fairness) ${\times}$ 2(customer satisfaction, customer behavior). The survey was performed on the customers who visited common restaurants, family restaurants, hotel restaurants, etc. mainly in Seoul, and total 600 sheets of questionnaires were distributed and 496 sheets of them were returned(82.67% of return ratio).

• Culinary science and hospitality research
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• v.23 no.7
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• pp.140-148
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• 2017

The purpose of this study was to provide basic data for the development of stir-fried rice cake (Tteok-bokki) products which are suitable for the organoleptic property of Chinese people based on the analysis results of the important considerations in choosing stir-fried rice cake (Tteok-bokki) for Chinese students. As a result of analysis, it was found that the texture of stir-fried rice cake (Tteok-bokki), smell, the harmony of the rice cake and sauce, the harmony of the rice cake and ingredients, the plate of food, the size of rice cake, the shape of rice cake, the color of sauce, and the sanitary condition of the food, ingredients, and cookware have significant influence. As a result of the IPA analysis, the texture of food, the sanitary condition of the food, ingredients, cookware, and a cook were included in the first quadrant, which indicates that it is batter to maintain a good quality. Smell of stir-fried rice cake (Tteok-bokki), temperature, rice cake and ingredients were included in the second quadrant, which suggests that the importance is high, but the satisfaction level is low.

• Computers and Concrete
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• v.10 no.4
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• pp.331-347
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• 2012

This paper describes the varying material model, the analysis method and the software development for reinforced concrete circular columns confined by spiral or hoop transverse steel reinforcement and subjected to eccentric loading. The widely used Mander model of concentric loading is adapted here to eccentric loading by developing an auto-adjustable stress-strain curve based on the eccentricity of the axial load or the size of the compression zone to generate more accurate interaction diagrams. The prediction of the ultimate unconfined capacity is straight forward. On the other hand, the prediction of the actual ultimate capacity of confined concrete columns requires specialized nonlinear analysis. This nonlinear procedure is programmed using C-Sharp to build efficient software that can be used for design, analysis, extreme event evaluation and forensic engineering. The software is equipped with an elegant graphics interface that assimilates input data, detail drawings, capacity diagrams and demand point mapping in a single sheet. Options for preliminary design, section and reinforcement selection are seamlessly integrated as well. Improvements to KDOT Bridge Design Manual using this software with reference to AASHTO LRFD are made.

• Journal of Information Processing Systems
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• v.11 no.3
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• pp.465-482
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• 2015

IEEE 802.11p is a standard MAC protocol for wireless access in vehicular environments (WAVEs). If a packet collision happens when a safety message is sent out, IEEE 802.11p chooses a random back-off counter value in a fixed-size contention window. However, depending on the random choice of back-off counter value, it is still possible that less important messages are sent out first while more important messages are delayed longer until sent out. In this paper, we present a new scheme for safety message scheduling, called the enhanced message priority mechanism (EMPM). It consists of the following two components: the benefit-value algorithm, which calculates the priority of the messages depending on the speed, deceleration, and message lifetime; and the back-off counter selection algorithm, which chooses the non-uniform back-off counter value in order to reduce the collision probability and to enhance the throughput of the highly beneficial messages. Numerical results show that the EMPM can significantly improve the throughput and delay of messages with high benefits when compared with existing MAC protocols. Consequently, the EMPM can provide better QoS support for the more important and urgent messages.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.808-814
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• 2010

Purpose: The sunken chest deformity without breast asymmetry is not a rare condition encountered in augmentation mammaplasty. Therefore, failure to recognize the deformity and improper surgical plan will lead to a suboptimal result. The authors review the experience of breast augmentation in simple sunken chest patient based on retrospectively collected data. Methods: From January, 2008 to January, 2009, patients with simple sunken chest underwent endoscopic submuscular augmentation mammaplasty through axilla, using silicone implants. Patient demographics were queried and outcomes were assessed. Results: Eleven patients (22 breasts) were followed up for 8.2 months after surgery. Sunken chests were augmented with implant size of approximately 248.9 cc (range: 213~286 cc) and contralateral chest with 211.4 cc (range: 180~235 cc). Simultaneous camouflaging the chest wall depression with breast augmentation resulted in good aesthetic outcome. All of the patients were satisfied with the surgery. There were no complications among all patients. Conclusion: We have demonstrated proper surgical planning with precise implant selection to optimize results in patients with small breast and simple sunken chest. Even though asymmetry still remains after the operation, it is still considered as acceptable.