• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.58-65
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• 2015

This paper presents the design of an implantable stimulation IC intended for neural prosthetic devices using $0.18-{\mu}m$ standard CMOS technology. The proposed single-channel biphasic current stimulator prototype is designed to deliver up to 1 mA of current to the tissue-equivalent $10-k{\Omega}$ load using 12.8-V supply voltage. To utilize only low-voltage standard CMOS transistors in the design, transistor stacking with dynamic gate biasing technique is used for reliable operation at high-voltage. In addition, active charge balancing circuit is used to maintain zero net charge at the stimulation site over the complete stimulation cycle. The area of the total stimulator IC consisting of DAC, current stimulation output driver, level-shifters, digital logic, and active charge balancer is $0.13mm^2$ and is suitable to be applied for multi-channel neural prosthetic devices.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.744-749
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• 2016

This paper presents the design of a computer-generated hologram for beam control of an LCOS-based wavelength selective switch, which is the core technology for next-generation ROADM. By introducing a computer-generated hologram instead of general grating patterns to control the LCOS device, we contribute to building a more efficient wavelength selective switch. With the use of phase modulation properties of LCOS devices, we designed the hologram for five-port output and a 40-channel wavelength selective switch. We applied a multi-level phase modulation technique with the Gerchberg-Saxton algorithm to produce the hologram, which is easily scalable to any different type of wavelength selective switch. With an experimental setup, we verified the usability of the hologram designed for five-port output. We also suggest a hologram design technique for beam control of a 40-channel wavelength selective switch.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.1002-1008
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• 2001

The absorbing structure composed of multi-layered fiber reinforced composite materials was designed and microwave absorbing properties are investigated. On the basis of transmission line theory, the theoretical equations to predict the reflection loss and the appropriate composite material for each functional layer are suggested. The most significant result of this study is the successful design and fabrication of triple-layered composite laminates which has the superior microwave absorbing porperties (more than 10 dB in 4∼12 GHz range), without using the ferrite filler in the impedance transforming layer. In the two-layered composite laminate (absorber/substrate), however, the use of ferrite filler (about 40 wt %) in the absorbing layer is necessary to obtain the certain level of microwave absorbance. By combining the glass-fiber composite with ferrite filler and carbon-fiber composite substrate, the microwave absorbing properties more than 10 dB in 4∼12 GHz frequencies than be obtained.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.319-324
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• 2006

Although the sera used in animal cell culture media provide the macromolecules, nutrients, hormones, and growth factors necessary to support cell growth, it could also be an obstacle to the production of recombinant proteins in animal cell culture systems used in many sectors of the biotechnology industry. For this reason, many research groups, including our laboratory, have been trying to develop serum-free media (SFM) or serum-supplemented media (SSM) for special or multi-purpose cell lines. The Chinese hamster ovary (CHO) cell, for example, is frequently used to produce proteins and is especially valuable in the large-scale production of pharmaceutically important proteins, yet information about its genome is lacking. Also, SFMs have only been evaluated by comparing growth patterns for cells grown in SFMs with those grown in SSM or by measuring the titer of the target protein obtained from cells grown in each type of medium. These are not reliable methods of obtaining the type of information needed to determine whether an SFM should be replaced with an SSM. We carried out a cDNA microarray analysis to evaluate MED-3, an SFM developed in our laboratory, as a CHO culture medium When CHO cells were cultured in MED-3 instead of an SSM, several genes associated with cell growth were down-regulated, although this change diminished over time. We found that the insulin-like growth factor (IGF) gene was representative of the proteins that were down-regulated in cells cultured in MED-3. When several key supplements - including insulin, transferrin, ethanolamine, and selenium - were removed from MED-3, the IGF expression was consistently down- regulated and cell growth decreased proportionately. Based on these results, we concluded that when an SFM is used as a culture medium, it is important to supplement it with substances that can help the cells maintain a high level of IGF expression. The data presented in this study, therefore, might provide useful information for the design and development of SFM or SSM, as well as for the design of genome-based studies of CHO cells to determine how they can be used optimally for protein production in pharmaceutical and biomedical research.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.11
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• pp.921-930
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• 2013

Satrec Initiative successfully developed and verified a high-resolution electro-optical camera system, EOS-D Ver.1.0. We designed this system to give improved spatial and radiometric resolution compared with EOS-C series systems. The thermal control subsystem (TCS) of the EOS-D Ver.1.0 uses heaters to meet the opto-mechanical requirements during in-orbit operation and uses different thermal coatings and multi-layer insulation (MLI) blankets to minimize the heater power consumption. Also, we designed and verified a refocusing mechanism to compensate the misalignment caused by moisture desorption from the metering structure. We verified the design margin and workmanship by conducting the qualification level thermal vacuum test. We also performed the verification of thermal math model (TMM) by comparing with thermal balance test results. As a result, we concluded that it faithfully represents the thermal characteristics of the EOS-D Ver.1.0.

• The KIPS Transactions:PartB
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• v.11B no.6
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• pp.683-690
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• 2004

Garment modeling and simulation is now one of the important elements in broad range of digital contents. Though there have been recent products on garment simulation, general users do not know well enough how to design a virtual costume that meets some requirements about its specific clothing pattern. In particular, Hanbok - the Korean traditional costume - has many different characteristics against western ones in the aspect of its pattern design and of draping. This paper presents a knowledge-driven approach for virtual Hanbok modeling without knowing how to make real Hanbok. First, parameterized knowledge for several fabric types art solicited using visual similarity assessment from simulated and real cloth. Secondly, based on the analysis of designer's knowledge, we defined multi-level adjustment processes of Hanbok measurements with regard to body shape features for different virtual actors. An experimental system is developed as the form of a Maya plug-in and the result shows the applicability of the proposed method.

• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.443-454
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• 2001

Software design patterns are reusable solutions to recurring problems that occur during software development. As programmers gain experience, they recognize the similarity of new problems to problems they have solved before. With even more experience, they recognize that solutions for similar problems follow recurring patterns. In this paper, as one of these reusable design-patterns, the Intermediator pattern for the efficient communication between business component is designed and implemented. Existent business components were way that follow Facade pattern. But Facade pattern is almost like the existing Interface pattern in that the communication of all the object outside the set is done by only one representative object, and this causes the traffic system to be overloaded. Therefore, the Intermediator pattern supplements the traffic overloads by improving the inefficient system of business components' communication through multi-interface, and make all communication behavior between objects done by Intermediator object which controls all actual behavior by way of Intermediator method implementation. Consequently, the Intermediator pattern is designed and implemented in this paper can bring down the level of coupling and raise the cohesion among objects, and refer to many of other object flexibly through several interfaces.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.4
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• pp.1-14
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• 2011

This study is to analyze the image similarity and the preference for clothing stores in the 6 giant discount chains in Daejeon. The survey for this study was based on the questionnaires accomplished by 257 people through the multidimensional scaling. The results are as follows First, 6 clothing stores had 4 image groups located in 4 coordinates. CW(Costco Wholesale), NH(Nonghyup Hanaro-Mart), and SZ(Save Zone) had a similar distinct image, while HP(Home Plus) and EM(E-Mart), and LM(Lotte-Malt) also had similar differentiated images. Second, according to the preference analysis in terms of demographic characteristic, NH had the lowest preference from the people of all the different ages, while SZ had the highest. HP, EM, CW, and LM had their own preference in the following order: in the thirties, forties, and over fifties. Meanwhile, relatively, SZ is preferred by the people in their twenties and people over age fifty liked CW more. Third, according to the analysis of the preference for clothing stores in the giant discount chains in terms of educational background, clothing consumers who had high school degrees preferred NH and LM, people with 2 year college degrees liked HP and EM more, while 4-year college graduates and people with higher education had preference for SZ. Finally, according to the preference analysis in terms of income level, higher income groups preferred SZ and CW and lower income groups liked LH and LM more, while HP and EM had high preference from all kinds of income groups.

• Journal of Fashion Business
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• v.5 no.5
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• pp.49-64
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• 2001

Fur is conceived as a material signifier, not only with its commodity value as luxury goods but also as its symbolic value as objects invested by one's libidinal desire. In this study, complex meanings of fur as multi-layered signs of political and sexual power focusing on fetishism shall be explored, especially on the spectacle fetishism acted by mass media during the anti-fur movement in the 1980s. In conjuction herewith, a highlight shall also be made to the symbolic value in fashion design since 1990s. In this study, first, as a theoretical investigation, fetishism, that has been traditionally considered only as sexual fetishism in fashion discourse will be explored in socio-economic level. Second, in historical context, how the meanings and values of fur have become realized in various cultural spaces, such as literature, art, film and finally, fashion will be viewed. In fashion, fur is a product of desire and power influenced by commodity fetishism as well as sexual fetishism. During the anti-fur movement, mass media has developed the concept of spectacle fetishism. Fur is a sign of animal-victim, and fur-clad women is viewed with images full of imperialsm, sexism and racism, thus act as derisive spectacles of consumerism. Since 1990s as a reflection on anti-fur movement, fetishistic characteristics, which challenge traditional operation method, are expressed by disguise, parody, and returning to the nature. First, fur as disguise is intended to hide sexually perverse, decadent characteristics and expensiveness of fur by texturing or patterning techniques. Second, fur as parody uses fake fur or dyed fur in order to satirize erotically and ethnographically fetishized meanings of fur. Third, aboriginal design of fur is adapted to use symbolic values outside the West, which can potentially mobilize antagonistic oppositions out of their fetishistic regimes. In conclusion, fur as sign of female sexuality and its libidinal profits of exchange, has significant symbolic values expressed in fashion.

• Earthquakes and Structures
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• v.8 no.5
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• pp.1255-1276
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• 2015

The importance of considering soil-structure interaction effect in the analysis and design of RC frame buildings is increasingly recognized but still not penetrated to the grass root level owing to various complexities involved. It is well established fact that the soil-structure interaction effect considerably influence the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic lateral loads. In the present work, the linear soil-structure analysis of a G+5 storey RC shear wall building frame resting on isolated column footings and supported by deformable soil is presented. The finite element modelling and analysis is carried out using ANSYS software under normal loads as well as under seismic loads. Various load combinations are considered as per IS-1893 (Part-1):2002. The interaction analysis is carried out with and without shear wall to investigate the effect of inclusion of shear wall on the total and differential settlements in the footings due to deformations in the soil mass. The frame and soil mass both are considered to behave in linear elastic manner. It is observed that the soil-structure interaction effect causes significant total and differential settlements in the footings. Maximum total settlement in footings occurs under vertical loads and inner footings settle more than outer footings creating a saucer shaped settlement profile of the footings. Each combination of seismic loads causes maximum differential settlement in one or more footings. Presence of shear wall decreases pulling/pushing effect of seismic forces on footings resulting in more stability to the structures.