• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.415-418
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• 2007

This paper presents the design and analysis of LNA-Mixer for 2.45GHz RFID reader. The LNA is implemented by PCSNIM method for low power consumption. The Mixer is implemented by using the Gilbert-type configuration, current bleeding technique, and the resonating technique for the tail capacitance. The connection between the two designed circuits is made by active balun. This LNA-Mixer has about 35dB for -40dBm input RF power, LO power is 0dBm and RF frequency is 2.45 GHz and IIP3 is -4dBm. The layout of LNA-Mixer for one-chip design in a $0.18-{\mu}m$ TSMC process has 2.6mm ${\times}$ 1.3mm size.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.11
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• pp.1982-1987
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• 2007

This paper presents the design and analysis of LNA-Mixer for 2.45GHz RFID reader. The LNA is implemented by PCSNIM method for low power consumption. The Mixer is implemented by using the Gilbert-type configuration, current bleeding technique and the resonating technique for the tail capacitance. The connection between the two designed circuits is made by active balun. This LNA-Mixer has about 22dB gain and 8.5dB Noise Figure for -50dBm input RF power, LO power is 0dBm, RF frequency is 2.45 GHz and IF frequency is 100kHz. The layout of LNA-Mixer for one-chip design in a 0.18-um TSMC process has $2.5mm{\times}1.0mm$ size.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1157-1160
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• 1998

This paper describes the design of a block data flow architecture(BDFA) which implements 2-D discrete wavelet transform(DWT)/inverse discrete wavelet transform(IDWT) for real time image processing applications. The BDFA uses 2-D product separable filters for DWT/IDWT. It consists of an input module, a processor array, and an output module. It use both data partitioning and algorithm partitioning to achieve high efficiency and high throughput. The 2-D DWT/IDWT algorithm for 256$\times$256 lenna image has been simulated using IDL(Interactive Data Language). The 2-D array structured BDFA for the 2-D filter has been modeled and simulated using VHDL.

• Korean Journal of Computational Design and Engineering
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• v.11 no.6
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• pp.412-421
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• 2006

Recently, the needs for sharing and exchanging drawing information between 2D and 3D data in complex facilities are well recognized throughout the construction industries. The purpose of this study is to propose an information framework to represent 3D IFC (Industry Foundation Classes) -based drawing of building services in complex facilities as 2D drawing. In this study, 1) attributes of building service objects which are used in 3D CAD system are analyzed and present drawing standards are analyzed, 2) based on the analysis, an information framework is developed to represent 3D model in 2D representation, and 3) further more, to test a compatibility of the information sharing framework, number of standardized APIs and an IFC2Dbrowser are developed during the study.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.203-207
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• 2008

The production process of the 3D-animation roughly consists of the pre-production, the main-production and the post-production. The pre-production, which is not only the outset of whole procedure among them but also the process to predict and design overall plan collectively is the most important step. A much more specific and perfect pre-production structure is needed to produce a high quality 3D-animation. Moreover, the standard 3D efficient lighting model is gathering strength as 2D and 3D artworks which are completed in this step maintain colors and looks in the main as well as post-production consistently. This study will make up for the weak points and help both to predict the color range of the overall 3D-animation product and to promote the application range of the 3D lighting system on the pre-production stage by developing the standard 3D lighting model applicable on the early step and calculating its lighting parameter properties.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.2
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• pp.9-16
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• 2008

To assess the preference and efficacy of empirical fitting methods with spheric and aspheric RGP lenses. Methods: Healthy 37 subjects were fitted with spheric design (diameter 9.3 mm) on right eye and aspheric design (dia 9.6 mm) on the left eye. Base curves which were fitted empirically (using on-K, Kavg-0.50D (or 1.00D) and manufacturer's recommended fitting guide) were compared with another base curve which obtained the best diagnostic fit with spheric and aspheric RGP lenses. The preference and fitting type (lid attachment or interpalpebral) for two design lenses were investigated 2 weeks after fitting RGP lenses. Results: Of 33 successful RGP lens-wearing subjects, 76% preferred spheric design compared with 24% of aspheric RGP lens wearers. Sixty seven percent were fitted with lid-attachment in spheric lenses, whereas 64% were fitted with lid-attachment in aspheric lenses. The acceptable fit success rates within ${\pm}$0.50D of base curves were 97% for the on-K fit, 100% for the Kavg-0.50D fit and 100% of the manufacturer's guide fit compared with the diagnostic fit in spheric design, whereas 91%, 79% and 94% reported on-K, Kavg-1.00D and manufacturer's guide, respectively, in aspheric design. Conclusions: Although aspheric RGP lenses are more popular in the Korean market, it is still preferable to fit subjects with spheric RGP lenses. Empirical fitting may be best accomplished with the spheric lenses using Kavg-0.50D fit and the manufacturer's fitting guide, whereas aspheric RGP lens designs are unacceptable lens fit based on empirical fitting.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.3
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• pp.33-47
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• 2017

The purpose of this study is to provide fundamental data for the development of new course on 3D printing in the fashion design department. In order to investigate the perception of and educational needs in 3D printing, the data were collected from 266 students (female 68.8%, male 31.2%) majoring in fashion design aged 18-25 living in the capital area. The results of this survey showed that when investigating perceptions of 3D printing, it was found that 68.8% of answerers had indeed heard of 3D printing. Regarding the path they came to know about 3D printing, mass media such TV was the most frequent answer (54.6%). On the other hand, to the question asking about their intention to take the subject if given, approximately 71% said "Yes". Also, if a modeling class were given, the division that they wanted to explore most in the fashion industry was fashion jewelry. Finally, to the question asking interest in starting a business, 71.1% answered that they had interest. Out of those that answered that they had interest, when questioned about in which field they wanted to start a business, the most frequent answer was fashion online shopping mall. Finally, NCS-based 3D printing courses were suggested in the Fashion Design area. As 3D printing techniques are actively applied to the fashion industry overseas, creative education is needed through the integration of fashion and 3D printing technology by introducing 3D printing related programs in colleges.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.130-135
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• 2008

An aerodynamic optimization design process of multistage axial turbine is presented in this article: first, applying quasi-three dimensional(Q3D) design methods to conduct preliminary design and then adopting modern optimization design methods to implement multistage local optimization. Quasi-three dimensional(Q3D) design methods, which mainly refer to S2 flow surface direct problem calculation, adopt the S2 flow surface direct problem calculation program of Harbin Institute of Technology. Multistage local optimization adopts the software of Numeca/Design3D, which jointly adopts genetic algorithm and artificial neural network. The major principle of the methodology is that the successive design evaluation is performed by using an artificial neural network instead of a flow solver and the genetic algorithms may be used in an efficient way. Flow computation applies three-dimensional viscosity Navier Stokes(N-S) equation solver. Such optimization process has three features: (i) local optimization based on aerodynamic performance of every cascade; (ii) several times of optimizations being performed to every cascade; and (iii) alternate use of coarse grid and fine grid. Such process was applied to optimize a three-stage axial turbine. During the optimization, blade shape and meridional channel were respectively optimized. Through optimization, the total efficiency increased 1.3% and total power increased 2.4% while total flow rate only slightly changed. Therefore, the total performance was improved and the design objective was achieved. The preliminary design makes use of quasi-three dimensional(Q3D) design methods to achieve most reasonable parameter distribution so as to preliminarily enhance total performance. Then total performance will be further improved by adopting multistage local optimization design. Thus the design objective will be successfully achieved without huge expenditure of manpower and calculation time. Therefore, such optimization design process may be efficiently applied to the aerodynamic design optimization of multistage axial turbine.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.5 s.164
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• pp.692-704
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• 2007

Recently, Basic patterns with excellent body fitness and automation availability are required to be developed in order to automate the patterns of women's clothes. In this study, this reference points, reference lines and segments were fixed onto 3D scan data for the lower body the women in their twenties, they were directly spread out to be 2D flat pattern to facilitate development into the design of slacks adhered closely to the human body such as special and highly-functional clothes, and then slacks 2D pattern was developed for the purpose of seeking scientific approach to the development into basic form slacks and 3d emotional pattern. For conversion of 3D pattern into 2D flat pattern, reference points and segments were created by using Rapid Form of 3D shape analysis software, and triangle mesh of the body surface of the created shape was developed with Auto CAD 2005. The correspondence between slacks and human body was examined by the fixation of major reference lines. Specially, the wearing characteristics of slacks were considered by the fixation of side lines in consideration of posture. As a result of using the way of development to constantly maintain the length while 3D triangle mesh is converted into 2D flat mesh, the shape was shown to be excellently reproduced, and the area of flat pattern was increased compared to the shape of parting plane. Also, the sunk-in curve like the brief line of front crotch length needed a cutting line when it was closely adhered, when mesh was overlapped, and the pattern area was smaller compared to the actual shape.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1940-1946
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• 2006

The influence of environmental conditions on the ganoderic acid (GA) content in the fungus Ganoderma lucidum was investigated using a one-factor-at-a-time design and orthogonal design. Among the various medium components examined, sucrose, soybean powder or peptone, ferrous sulfate, and pH 6.0 were the most suitable carbon source (factor A), nitrogen source (factor B), mineral source (factor C), and initial pH (factor D), respectively, for the GA content in the one-factor-at-a-time design. According to the orthogonal design, the order of effect for the four factors on the GA content was A>C>D>B. The best level of factor A was $A_2$ (sucrose) with a value of +0.34 mg/100 mg DW. The optimal treatment combination was $A_2B_1C_3D_1$ with which the GA content reached up to 2.63$\pm$0.011 mg/100 mg DW. The interactions between the mineral ion and the nitrogen source, and the mineral ion and the pH were both highly significant (P<0.01). The highest interaction effect was ($B_2{\times}D_2$) with a value of +0.19 mg/100 mg DW, which was higher than the level effect value for $B_2$ (peptone) and D$_2$ (pH 5.0). Therefore, the results proved that interactions between factors cannot be ignored. The results also indicated the importance of the interactions between the factors, which may help to understand the metabolic pathway leading to triterpene biosynthesis and the expression and regulation of the key enzymes involved.