• IEMEK Journal of Embedded Systems and Applications
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• v.7 no.4
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• pp.187-191
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• 2012

In these days, there are huge increases of concerning underwater acoustic sensor networks (UWASNs) to explore marine resources and to monitor climate change. To collect information from sensor nodes which are randomly deployed in underwater, Multi-Dimensional Scaling (MDS) based locating methods have been recently introduced, which consider sound speed to be constant in underwater. However, underwater sound speed tends to vary depending on underwater environment factors, such as depth, temperature, and salinity. In this paper, we propose a method considering environment factors, can influence upon sound speed in underwater, and introduce experimental setup which can follow up environmental factors.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.2
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• pp.180-187
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• 2007

In this paper, we propose an automatic method which combines two or more images acquired by camera on the air-vehicle into a larger image mosaics. The shift, scaling, rotation factors between two images can be calculated by using the correspondences between the points of the images. In order to estimate these factors, we find the relative positions of two images with respect to each other by using the SIFT descriptor and the RANSAC algorithm. After estimating the factors, the images can be merged into a single image mosaic by warping the target image. To avoid seams when mosaics are constructed from overlapped images, we apply the average gray level value of points within a overlapped zone. We have tested our proposed method on various image sets and have confirmed that our method produced good result subjectively.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.109-111
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• 2003

Compared to the present clinical field strengths, MR at 47 and above promises to improve anatomic imaging quality by factors, and to bring metabolic and functional imaging to the forefront of research and diagnostic modalities. While human bore sized magnets as high as 9.4T are now installed, realization of the potential benefit of these magnets will require more of the MR system than a simple field, frequency or power scaling from technologies used at lower fields. New constraints on the high field MR studies, both physical and physiological, will require new technical developments to be considered for the highest field systems.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.77-78
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• 2012

To predict combustion instability in actual full-scale combustion chamber of rocket engines, air-injection test is proposed with scaling techniques. From the data, damping factors have been obtained as a function of hydraulic parameter and the data give us instability map. Two instability regions are presented and it is found that they coincide reasonably with them from hot-fire test with full-scale flow rates. Accordingly, the proposed approach can be applied cost-effectively to stability rating of jet injectors when mixing of fuel and oxidizer jets is the dominant process in instability triggering.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.12a
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• pp.213-216
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• 2000

퍼지제어기를 실제 플랜트에 적용할 경우, 모델링 오차와 플랜트에 대한 관련지식의 부족으로 만족할 만한 제어 결과를 기대하지 못한다. 이러한 경우 제어기 성능을 향상시키기 위해 제어인자를 다시 조정해야 하고, 이 조정과정은 시행착오방법으로 수행되기 때문에 많은 시간과 비용을 필요로 한다. 본 논문에서는 퍼지 논리를 사용하여 스케일링 계수를 자동조정하는 퍼지 레귤레이터를 제안하였다. 스케일 계수의 출력 범위와 오차, 오차 변화량 따라 퍼지 레귤레이터는 적절한 스케일링 계수값을 결정함으로써 퍼지제어기의 성능을 향상시키게 된다. 제안한 방법의 타당성을 확인하기 위해 2차 플랜트에 적용하여 모의실험을 수행하였다.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2702-2704
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• 2001

In this Letter, we propose a comprehensive design methodology of hybri'd Fuzzy controllers (HFC). The HFC comes as a form of a convex combination of a standard PID controller and a fuzzy controller. The design procedure dwells on the use of evolutionary computing (genetic algorithm) and an auto-tuning algorithm. The tuning of the scaling factors of the HFC is an essential component of the entire optimization process. A numerical study is presented and a detailed comparative analysis is also included.

• Journal of the Korean Mathematical Society
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• v.59 no.1
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• pp.35-51
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• 2022

We give secure parameter suggestions to use sparse secret vectors in LWE based encryption schemes. This should replace existing security parameters, because homomorphic encryption (HE) schemes use quite different variables from the existing parameters. In particular, HE schemes using sparse secrets should be supported by experimental analysis, here we summarize existing attacks to be considered and security levels for each attacks. Based on the analysis and experiments, we compute optimal scaling factors for CKKS.

• Journal of Fashion Business
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• v.6 no.4
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• pp.141-150
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• 2002

The purpose of this study was to investigate factors to influence on buying behavior of Chinese male consumers in regards to apparel types. Furthermore, this study provided fundamental data for marketing strategy in export apparel business to China from domestic apparel business. Returned 863 questionnaires from Chinese male consumers analyzed by factor analysis, and multidimensional scaling with SPSS10.0. The result of this study were as follows: Chinese male consumers bought formal wear with evaluating two groups of factors; one for functional (fitness, A/S, durability, and management), the other for external (brand, and trend). They bought casual wear with evaluating three groups of factors; functional/useful (price, A/S, and durability), aesthetic (color, and design), and external (brand and trend). Also they bought sports wear with evaluating three groups of factors; functional/useful(price, A/S, durability, and fabric), aesthetic(design and color), and external(brand and coordination).

• Journal of Technologic Dentistry
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• v.34 no.1
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• pp.25-36
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• 2012

Purpose: The purpose of this study is to investigate the status of oral health behaviors and oral health status, and to analysis the association between health behavior and chronic disease and oral health status of male workers. Methods: The survey used structured self administered questionnaires from September to October in 2009 in Daegu and Gyeongsangbuk-do province, randomize thirty workplace which work more than 50 workers and carry out a survey targeting 30 to 50 age male laborers who work selected workplace. Total of 1,532 replies were analysed. Results: Age, education, monthly income, job was significantly associated with number of toothbrushing, scaling experience, number of missing teeth. Smoking, amount of smoking, frequency of drinking, number of tooth brushing, unmet need and subjective oral health condition, HBP and DM was significantly associated with the number of missing teeth. In logistic regression, age(above 40), monthly income and DM were significant factors on loss of teeth. Conclusion: In conclusion, it is important to provide education on the teeth-brushing and DM management to workers engaged in a small or medium sized workplace with many tooth loss and low educational status, and to recommend a regular scaling as well as to establish policy for creating conditions upon an oral health check-up and a tooth scaling and allow the maintenance of an oral health.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.360-365
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• 2016

The purpose of this study is to provide the basic information for the early enforcement and extension of the improvement project of management scale of private forest land by understanding the characteristics of forest owners, who have an influence on the participation of the project as one of the private forest management vitalization plans. To achieve this goal, a questionnaire survey targeting 373 forest owners was conducted and analyzed by Binary-Logistic Regression. The variables for binary-logistic regression included gender, age, academic ability, occupation, income, residence, purpose of forest ownership, and status of cooperative membership. As a result of the analysis, 267 forest owners (71.6%) of total 373 forest owners have the intention to participate in the scaling project for private forest management. The rest of forest owners (106 forest owners, 28.4%) would not be willing to participate in the project. As a result of binary-logistic regression, the most important variables, which have an impact on the participation of private forest management scale improvement project, are age, job and forest own purpose.