• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.126-142
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• 2016

This paper presents a wide-frequency-range, low-power transceiver with an automatic impedance-matching calibration for TV-white-space (TVWS) application. The wide-range automatic impedance matching calibration (AIMC) is proposed for the Drive Amplifier (DA) and LNA. The optimal $S_{22}$ and $S_{11}$ matching capacitances are selected in the DA and LNA, respectively. Also, the Single Pole Double Throw (SPDT) switch is integrated to share the antenna and matching network between the transmitter and receiver, thereby minimizing the systemic cost. An N-path filter is proposed to reject the large interferers in the TVWS frequency band. The current-driven mixer with a 25% duty LO generator is designed to achieve the high-gain and low-noise figures; also, the frequency synthesizer is designed to generate the wide-range LO signals, and it is used to implement the FSK modulation with a programmable loop bandwidth for multi-rate communication. The TVWS transceiver is implemented in $0.13{\mu}m$, 1-poly, 6-metal CMOS technology. The die area of the transceiver is $4mm{\times}3mm$. The power consumption levels of the transmitter and receiver are 64.35 mW and 39.8 mW, respectively, when the output-power level of the transmitter is +10 dBm at a supply voltage of 3.3 V. The phase noise of the PLL output at Band 2 is -128.3 dBc/Hz with a 1 MHz offset.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.6
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• pp.80-88
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• 2008

In this paper, the block cipher algorithms, 3-DES(Triple Data Encryption Standard), AES(Advanced Encryption Standard), SEED, HASH(SHA-1), which are domestic and international standards, have been implemented as an integrated cryptographic engine for smart card applications. For small area and low power design which are essential requirements for portable devices, arithmetic resources are shared for iteration steps in each algorithm, and a two-level clock gating technique was used to reduce the dynamic power consumption. The integrated cryptographic engine was verified with ALTERA Excalbur EPXA10F1020C device, requiring 7,729 LEs(Logic Elements) and 512 Bytes ROM, and its maximum clock speed was 24.83 MHz. When designed by using Samsung 0.18 um STD130 standard cell library, the engine consisted of 44,452 gates and had up to 50 MHz operation clock speed. It was estimated to consume 2.96 mW, 3.03 mW, 2.63 mW, 7.06 mW power at 3-DES, AES, SEED, SHA-1 modes respectively when operating at 25 MHz clock. We found that it has better area-power optimized structure than other existing designs for smart cards and various embedded security systems.

• Journal of The Korean Association For Science Education
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• v.38 no.4
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• pp.587-598
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• 2018

In this study, we investigated the characteristics of pre-service science teachers' curriculum design for lessons using self-generated analogy. Three pre-service science teachers at a college of education in Seoul participated in this study. After a workshop on lessons using self-generated analogy, they planned and demonstrated lessons. All of the teaching-learning materials were collected, and their lessons were observed and videotaped. Semi-structured interviews were also conducted before and after their lessons. The characteristics of lessons using self-generated analogy were analyzed in the perspectives of PCK. The analyses of the results revealed that they used various strategies to promote students' generating analogies. They lacked understanding of the stages of the lessons and the role of teachers. Although all of them considered assessment, they used limited assessment methods and assessment dimensions. Some actively considered students' misconceptions, and specifically anticipated analogies that students could generate. They determined topics for lessons considering various aspects such as the level of self-generated analogy and the characteristics of scientific conceptions. On the bases of the results, we suggest some educational implications for pre-service science teacher education.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.11 s.353
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• pp.26-36
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• 2006

In this paper, we propose a cost-effective color filter may (CFA) demosaicing method for digital still cameras in which a single CCD or CMOS image sensor is used. Since a CFA is adopted, we must interpolate missing color values in the red, green and blue channels at each pixel location. While most state-of-the-art algorithms invest a great deal of computational effort in the enhancement of the reconstructed image to overcome the color artifacts, we focus on eliminating the color artifacts with low computational complexity. Using spatial correlation of the adjacent pixels, the edge-directional information of the neighbor pixels is used for determining the edge direction of the current pixel. We apply our method to the state-of-the-art algorithms which use edge-directed methods to interpolate the missing color channels. The experiment results show that the proposed method enhances the demosaiced image qualify from $0.09{\sim}0.47dB$ in PSNR depending on the basis algorithm by removing most of the color artifacts. The proposed method was implemented and verified successfully using verilog HDL and FPGA. It was synthesized to gate-level circuits using 0.25um CMOS standard cell library. The total logic gate count is 12K, and five line memories are used.

• Spatial Information Research
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• v.21 no.2
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• pp.35-43
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• 2013

The aim of this research is to analyze the priority to functions of the U-city Service Aid Organization(USAO), which is to support invigorating U-City industry. This research analyzes the relative importance and the priority about the functional area and components of UASO based on AHP. This research also performs a sensitivity analysis. The research result shows that relative importance of functional area is like following orders: 1) distribution of U-City service-related information, 2) quality certification of U-City-related products and services, 3) R&D of U-City technology, 4) standardization of U-City, 5) U-City human resource development. The relative importance order of functional components is 1) establishment of U-City information distribution organization, 2) construction and management of U-City information distribution network, 3) supporting U-City information distribution and price policy, 4) providing U-City information list for distribution, 5) preparation and application of quality certification standard of U-City products and services, 6) research on legal system of U-City items, targets, and procedures for quality certification, 7) research, analysis, and provision of U-City information distribution situation, 8) level examination of constructed infrastructures and services in U-City, 9) U-City core technology development and localization of technology, 10) standardization of collected U-City information, service classification, distribution system. This research result can be applied directly to design functions of USAO. The result also can be used for duty management, human resource planning, or resource allocation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.5
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• pp.486-492
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• 2004

In this paper, we newly propose the binary CA-CDMA(constant amplitude CDMA) system using pre-coding method to solve the high PAPR problem caused by multi-user signal transmission in the CDMA system. 4-user CA-CDMA, the basis of proposed binary CA-CDMA system, makes binary output signal for 4 input users. It produces the output of binary(${\pm}$2) amplitude by using a parity signal resulting from the XOR operation of 4 users data. Another sub-channel or more bandwidth is not necessary because it is transmitted together with user data and can be easily recovered in the receiver. The extension of the number of users can be possible by the simple repetition of the basic binary 4-user CA-CDMA. For example, binary 16-user CA-CDMA is made easily by allocating the four 4-user CA-CDMA systems in parallel and leading the four outputs to the fifth 4-user CA-CDMA system as input, because the output signal of each 4-user CA-CDMA is also binary. By the same extension procedure, binary 64 and 256-user CA-CDMA systems can be made with the constant amplitude. As a result, the code rate of this proposed CA-CDMA system is just 1 and binary CA-CDMA does not change the transmission rate with the constant output signal(PAPR = 0 ㏈). Therefore, the power efficiency of the HPA can be maximized without the nonlinear distortion. From the simulation results, it is verified that the conventional CDMA system has multi-level output signal, but the proposed binary CA-CDMA system always produces binary output. And it is also found that the BER of conventional CDMA system is increased by nonlinear HPA, but the BER of proposed binary CA-CDMA system is not changed.

• Journal of the Korean Home Economics Association
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• v.32 no.5
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• pp.165-182
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• 1994

Korea's clothing industry which has been country's leading export industry and basic strategical industry is now faced with many difficulties both domestically and internationally. Domestically it is faced with continuing shortage of manpower in both production line and management high labour cost causing increase in price putting more weight on behavior of consumers resulting in change of industrial environment and continuing structural problems of industry itself. Internationally it is faced with strengthening of import regulations and protectionism of developed countries and rapid emergence of underdeveloped countries as leading exporting nations. In reality export plays the most essential role in our economy and is especially sensitive to the external environmental factors. Already economic bloc phonomenon can be seen everywhere and is continuing to accelerate in place such as E. U in Europ, North & South America as NAFTA, and South East Asian contries which recent tendency of economic unity effort is present. These countries of such economic blocs are imposing heavy custom duties reinforcing provision of country origin and acting out strict inspection regulations in order to protect the interest of their own industry. Therefore it is vital to manufacture excellent quality goods For these reasons study in this area has brought attention in Korea as well as worldwide in the recent years. Apparel industry which requires professional technology and ability is the most competitive international business. In order to challenge the international market the high level of intelligence is most required to produce high quality goods. The purpose of this study is to analyze the relationship between functions and roles of marketing and to approach problems in more efficient manner. Apparel industry is composed of various programs such as design pattern making merchandising and textile science. To succeed in the business is to give the highest satisfaction to the targeted market. Hence this study will example the factors that determine the Cost Quality and Performance of apparel products. The study will involve following steps; firstly establish relationship between the quality concept and productivity of apparel products Secondly inquire in to marketing strategy laying stress on apparel production related factors focusing on merchandising marketing production and operations Thirdly prospect 21st century apparel industry focusing on garment production and trade and also other countries structural improvement Fourthly establish the new dimension of competitive factors by grasping the actual circumstance of Korea's apparel industry in the international market. The research method will include; First reality approach method by analysing the present state of industry Second literal analysis such as marketing comparisons between leading apparel exporting countries.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.1
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• pp.199-210
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• 2015

This study analyzes various aspects of the successful overseas expansion of SMEs that export consumer goods with their own brands. Through in-depth interviews with CEOs and marketing practitioners of fifteen SMEs that export consumer goods of their own brands, researchers examined the determinants of the decisions to export own-brand products, forms of expansion into foreign markets, firms' distribution networks, firms' technological and marketing capabilities, export barriers, and export support services offered by the government. The results indicate that these companies obtained competitiveness in the design and quality of their products through steady R&D investment, with a focus on niche markets. This study also shows that they established foreign branches, participated in overseas trade fairs, and tapped into foreign markets with Korean home shopping channels and department stores to build distribution channels and to find new buyers. However, the findings of this study reveal that many of those companies export both OEM/OEM products as well as their own-brand products due to the low level of brand awareness in foreign markets. Thus, efforts to improve their brand awareness in the global market are much needed. In addition, this paper demonstrates that the programs and services provided by state-run organizations need improvement in credibility and expertise. This research suggests recommendations for successful export programs, and provides meaningful insights for consumer-goods SMEs establishing foreign market entry strategies with their own brands.

• Journal of the Korean Society of Costume
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• v.57 no.2 s.111
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• pp.69-85
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• 2007

Despite the recovery of consumer expenditure and retailing in the Korean economy after 2001, the domestic apparel industry has been aggravated by negative growth in both productivity and production. The purpose of the stud? is to diagnose the develop competitive of the Korean apparel industry and derive implications for this after estimating the efficiency of the Korean apparel companies with Data Envelopment Analysis. Data Envelopment Analysis(DEA) is a methodology based in non-parametric analysis and linear programming. It was developed for measuring the relative efficiency of a set of firms that use inputs to produce outputs. Data used fer input and output variables in the analysis are drawn from financial statement recorded by the Korean Financial Supervisory Service. The initial input data comprise the number fo the employees, fixed assets, general management and selling expenses, and cost of sales. The initial outputs are the operating profit and the gross margin. To summary the results, the efficiencies of the Korean apparel companies has increased yearly in spite of being overabundance of investment in Labour and Capital. According to correlation between input and output variables, the Korean apparel industry has been revamping gradually from labor intensive industries to the capital. The companies need to reduce costs in the results from the number of employees, fixed asset and cost of sales to transform into an efficiently enterprise. The companies owning or obtaining a brand had bitter establish an outsourcing strategic in production, while OEM corporations are called far setting up a manufactory in domestic or abroad. Although the paper is derived some implications with production efficiencies, the relation between apparel companies and brand power, consumption level of consumer, and social trend is remained on a limitation to the study. The next research necessitates a topic with Fashion industry or examining the correlation between brand value, social propensity and profit margin.

• Journal of the Korean Society of Costume
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• v.44
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• pp.181-199
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• 1999

The industry of modern clothing has deviated from the overflow of commercialism and the standardization and nowadays is going toward pursuing art, creativity, and high added value. This trend brings the return of the natural materials from the synthetic textiles and increases the value of old and handmade fabrics. Finally, the handmade-paper, which is a natural material, comes to be reconsidered as a new material for the clothing. Therefore, as the natural materials and the manufacture of handmade clothing are rising again, the qualitative improvement and globalization of clothing industry should be first realized through the developments of creative and various clothing materials and new expressing techniques. The above investigation and study have been synthesized and analyzed as follows: First, through the study on the origin of the paper clothing, its historical background and the process of its development, we've learned these two facts following : the paper clothing of the East in the past mostly had practiced meanings. On the other hand, in the West it had meanings which were raised the artist's emotions and beauty-consciousness to the artistic level by the various kinds of expressing methods. Second, handmade-paper was manufactured by the embedding method, which mixed mulberry pulp, gauze, corn, hair, sisal, silk and so on. It was found that handmade-paper had the affluent and proper texture as the clothing material and was be able to control the clarity through the variation of thickness. It was also confirmed that the creative and original texture with hand-worked molding beauty was obtained by the use of handmade-paper. Third, when the handmade-paper is used, the molding beauty of plane, relievo, and solid can be freely pursued, and various and effective molding conformation can be constructed by the effect of superposition and repetition. Also, because the maximum discretion from the various optional manufacturing methods is allowed, the molding beauty can be maximized when the clothes are manufactured with handmade-paper. Fourth, the gauze with strong drape was combined to overcome the stiffness and the tearing of the paper. As a result, the durability and the wearability of the paper were strengthened and thus the thus the applications as the clothing material were enlarged. In conclusion, in order to enhance the value, creativity, practicality, and artistic sense of the design for modern clothing, the clothes made of handmade-paper should be more studied. Moreover, for the generalization of paper clothes, the studies on the development of practical paper with paper with water resistance, post-treatment after dyeing, flexibility, and durability should be done. I really hope that this study will be the motive to provoke the possibility of handmade-paper as new clothing material in not only practical sense but also artistic sense.