• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.6
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• pp.706-715
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• 2012

Electro-optical sigma-delta modulators are the core module of digital receiver to digitize wideband radio-frequency signals directly at an antenna. Electro-optical sigma-delta modulators use a pulsed laser to oversample an input radio-frequency signals at two Mach-Zehnder Interferometer(MZI) and shape the quantization noise using a fiber-lattice accumulator. Decimation filtering is applied to the quantizer output to construct the input signal with high resolution. The jitter affects greatly on reconstructing the original input signal of modulator. This paper analyzes the performance of first order single bit electro-optical sigma-delta modulator in the time domain and the frequency domain. The performance of modulator is analyzed by using asynchronous spectral averaging of the reconstructed signal's spectrum in the frequency domain. The reference value of time jitter is presented by analyzing the performance of jitter effects. This kind of jitter value can be used as a reference value on the design of modulators.

• Journal of the Korean Society of Radiology
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• v.11 no.4
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• pp.213-219
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• 2017

The purpose of study is provide the basic data for set up proper illuminance of examination room that put purpose of an empirical study basic data about examination environment setting of the ultrasonic examination on design the examination environment of a new ultrasonic examination. As a method, to investigate the ultrasonic environment related to illumination to take a survey on the ultrasonic examination about test object to 48 parts of six units of general hospital in Busan. As a result, All Door + Curtain showed high scores in analyzing the gender, age, examination part in the case of ultrasonic examination room shielding and LED and light source control is required in the case of kind of light source. In the ultrasonic examination environment survey, the illuminance brightness is average 10 Lux which is included illuminance brightness range recommended the WHO and CEC and illuminance brightness of ultrasonic examination waiting room(ultrasonic examination waiting room, corridor) indicate average 300~800 Lux and it satisfied hospital illumination environment more than 300 Lux recommended by KSA 3011. In conclusion, Basic data suggested that improved future ultrasonic examination environment or designed new examination room on the basis of analysis result of general background and ultrasonic examination related to environment factor.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.510-518
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• 2018

Recently, lots of interests have been concentrated on the scrubber system that abates waste gases produced from semiconductor manufacturing processes. An effective design of the thermal decomposition reactor inside a scrubber system is significantly important since it is directly related to the removal performance of pollutants and overall stabilities. In the present study, a computational fluid dynamics (CFD) analysis was conducted to figure out the thermal and flow characteristics inside the reactor of wet scrubber. In order to verify the numerical method, the temperature at several monitoring points was compared to that of experimental results. Average error rates of 1.27~2.27% between both the results were achieved, and numerical results of the temperature distribution were in good agreement with the experimental data. By using the validated numerical method, the effect of the reactor geometry on the heat transfer rate was also taken into consideration. From the result, it was observed that the flow and temperature uniformity were significantly improved. Overall, our current study could provide useful information to identify the fluid behavior and thermal performance for various scrubber systems.

• Food Science and Preservation
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• v.13 no.2
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• pp.252-258
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• 2006

To find the optimum extraction condition of dried omija, central composite experimental design having three independent variable (extraction temperature, extraction time and water ratio) with five levels was conducted for response surface analysis. The maximum of soluble solid was predicted to the extraction conditions of over 25 fold water ratio, $7{\sim}8hr$ and $75^{\circ}C$. Total acid, total phenol, reducing sugar and vitamin C were predicted to respectively 30 fold water ratio, 6 hr, $70^{\circ}C$, 30 fold water ratio, $6{\sim}7\;hrs,\;80^{\circ}C$ and 30 fold water ratio, $6{\sim}8\;hr,\;80^{\circ}C$, 25 fold water ratio, $5{\sim}6hr,\;80^{\circ}C$ extraction condition. Turbidity of extraction condition. Turbidity of extraction condition was 7 over 25 ford water ratio and over $60^{\circ}C$. From the superimposing results of response variables, the optimum extraction condition was predicted 25 folds water ratio, 6 hr and $65{\sim}70^{\circ}C$.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.197-206
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• 2010

For an emotion retrieval system implementation to support pedestrian navigation, coordinating the pedestrian emotion model with the system user's emotion is considered a key component. This study proposes a new method for capturing the user's model that corresponds to the pedestrian emotion model and examines the validity of the method. In the first phase, a database comprising a set of interior images that represent hypothetical destinations was developed. In the second phase, 10 subjects were recruited and asked to evaluate on navigation and satisfaction toward each interior image in five rounds of navigation experiments. In the last phase, the subjects' feedback data was used for of the pedestrian emotion model, which is called ‘learning' in this study. After evaluations by the subjects, the learning effect was analyzed by the following aspects: recall ratio, precision ratio, retrieval ranking, and satisfaction. Findings of the analysis verify that all four aspects significantly were improved after the learning. This study demonstrates the effectiveness of the learning algorithm for the proposed pedestrian emotion model. Furthermore, this study demonstrates the potential of such pedestrian emotion model to be well applicable in the development of various mobile contents service systems dealing with visual images such as commercial interiors in the future.

• Journal of the HCI Society of Korea
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• v.1 no.1
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• pp.73-80
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• 2006

Mitologia is about visualizing relations of information in user-oriented method. Most information given in life has invisible relations with each other. By analyzing the common characters and relations of information, we can not only measure the importance of the information but also grasp the overall properties of the information. Especially human relations are the major concerns of social network having several visualization methodologies shown by analyzing relations of each individual in society. We applied social network theory to grasp relationships between characters in Greek mythology representing a limited society. But the current tools of social network analysis have limits that they show the information one-sided way because of the ignorance of user-oriented design. Mitologia attempts to suggest the visual structure model more effective and easy to understand in analyzing data. We extracted connections among myth characters by evaluating classes, frequencies of appearance and emotional links they have. And we raised the understanding of users with furnishing the proper interaction to the information. The initial interface offers 4 kinds of indexes helping to access character nodes easily, while zoom-in function can be used for the detailed relations. The Zoom-in is quite different from usual filtering methods. It makes the irrelative information invisible so that users can find out the characters' relation more easily and quickly. This project suggests the layout to show overall information relationships and the appropriate interactions to present detailed information at the same time.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1298-1305
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• 2020

Objective: The study aimed to understand the degree of improvement in damaged hair by applying mink oil. Methods: The agent used to improve hair texture is mink oil, which was applied in varying dosages (0, 1, 2, and 3 g). Hair characteristics were measured before and after applying mink oil to bleached hair for comparative analysis. To understand the effects of mink oil on hair texture, tensile strength, absorbance, and gloss were measured. Results: The results indicate a decrease in the tensile strength of damaged hair compared with healthy hair. Tensile strength at level 7 was achieved with high dosages of mink oil. Furthermore, the experimental group demonstrated an increase in absorbance compared with control. Compared to 0g for the control group, the absorbance values for the experimental group with mink oil dosages of 1, 2, and 3 g at level 7 decreased with the increased in mink oil dose. In terms of gloss, an increase was observed for bleached hair compared with healthy hair. At level 7, gloss decreased with the increase in mink oil dose. Conclusions: The results verified the improvement in hair texture after the application of mink oil to damaged hair. Future research should explore the effects of various oil ingredients on hair texture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.283-290
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• 2020

In this study, a floater was developed for a frame-type solar power plant. The floater supports the frame and the solar panels. A finite element analysis was performed to design its shape and thickness, and the floater was manufactured by a rotational molding method using linear low-density polyethylene. It was found that the floater did not cause collapse and it maintained its stiffness even at 4 times the maximum load of 322.7 kgf. To perform a long-term compression test, a weight-type load application device that uses gravity was designed and manufactured. The amount of compressive deformation was measured for 7 days, and a long-term deformation equation was obtained. Even under small loads, continuous deformation was observed. However, the 10-year deformation amount for a constant load of 100 kgf was predicted to be small at about 4.64 mm. As a result, it was found that the developed floater could be used in a solar power plant on a body of water.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1557-1565
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• 2014

The purpose of this study was to identify the factors influencing learning flow of nursing student. Design of this study was a descriptive research. The participants for this study were 283 nursing college students with four-years curriculum in D city from June 14th to June 24th, 2013. Data were analyzed using descriptive statistics, t-test, one way ANOVA, Pearson's correlation and multiple regression with SPSS 18.0 Program. There were significant correlations among self-leadership, academic self-efficacy, major satisfaction, and the learning flow. As a multiple regression analysis, factors that have an effect on learning flow were self-leadership, and academic self-efficacy. These factors explain 58.2% of the variance in learning flow. Self-leadership, academic self-efficacy, and learning flow relationship were positive relevant. To enhance learning flow ability for nursing students, it is necessary to develop training program and academic environment for increasing self-leadership and academic self-efficacy.

• The KIPS Transactions:PartD
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• v.12D no.4 s.100
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• pp.583-588
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• 2005

Being able to resolve huge problems deriving from integration of information systems in-house or business to business, the web service that uses the XML standard technology has recently taken a quick dominance the next generation e-business bases. It's one constant concern how to integrate, change, and maintain such systems as based on certain technologies according to the changes to information technology, which is on the ongoing process of evolution. To help solve those problems, OMG suggested a new software architecture called MDA(Model Driven Architecture). MDA runs a process that establishes a platform independent model(PIM), which is an analysis model used as part of the existing development procedures, and automatically converts it into a platform specific model(PSM), a design model, based on the established PIM. Such automatic conversion has lots of benefits including easy support for diverse platforms, reducing the coding time that usually consume a great deal of the developer's effort, and facilitating quality control in the aspect of development processes. By applying the MDA development process to a new web service development, you can choose web service as the target platform at the PIM of MDA and express PSM with a web service model, WSDL. This study set out to classify the web service development or integration processes by the provider md requester to identify the types of web service development processes, and to apply the MDA development process to web service development, thus suggesting a new kind of web service development process that can be referred to by both the web service provider and requester.