• Journal of Advanced Navigation Technology
• /
• v.20 no.2
• /
• pp.127-133
• /
• 2016

This paper proposes a case study of applying to DO-278A, which is a software development standard of ground aviation equipment in communication, navigation, surveillance/air traffic management (CNS/ATM) domain, in order to develop software of Advanced surface movement, guidance and control system (A-SMGCS). It explains considerations to application of DO-278A standard, discusses how to tailor processes or requirements specified in DO-278A in detail, and explain tailored results. And it also summary problems or issues occurred during application of DO-278A, which can be appeared when DO-278A is applied to for the first time by any development part. These are required considerations in order to reduce trial and error. To the conclusion, it explains lessons learned from application of DO-278A and suggest how to solve these problems or issues.

• Journal of the Korean Ceramic Society
• /
• v.53 no.6
• /
• pp.604-609
• /
• 2016

This study reports on wet-foam stability with respect to porous ceramics from a particle-stabilized colloidal suspension that is achieved through the addition of polymethyl methacrylate (PMMA) using a wet process. To stabilize the wet foam, an initial colloidal suspension of $Al_2O_3$ was partially hydrophobized by the surfactant propyl gallate (2 wt.%) and $SiO_2$ was added as a stabilizer. The influence of the PMMA content on the bubble size, pore size, and pore distribution in terms of the contact angle, surface tension, adsorption free energy, and Laplace pressure are described in this paper. The results show a wet-foam stability of more than 83%, which corresponds to a particle free energy of $2.7{\times}10^{-12}J$ and a pressure difference of 61.1 mPa for colloidal particles with 20 wt.% of PMMA beads. It was possible to control the uniform distribution of the open/closed pores by increasing the PMMA content and by adding thick struts, leading to the achievement of a higher-stability wet foam for use in porous ceramics.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.35 no.11
• /
• pp.1399-1408
• /
• 2011

This study analyzes the current educational curricula in the field of clothing construction to provide some fundamental information for developing more appropriate educational courses and to activate the fashion business. A total of 82 different departments related to fashion and apparel were selected from four-year domestic universities and the curricula recently posted on their internet websites were analyzed by descriptive statistics. More than half (53.7%) of the 82 departments were offering classes in the clothing construction field for 3 credits and 4 class hours. College affiliation of the departments that offered curricula in the clothing construction field was classified into 5 categories: the arts (34), human ecology (22), natural sciences (14), humanities/culture (9), and others (3). Human ecology category showed the highest results in the average class hours (3.9), the number of classes in the clothing construction field (7.6), and the percentage of the classes in the clothing construction field out of all major classes offered by the clothing department (19.9%). All 82 departments were classified into 3 categories of: fashion design (32), clothing (28), and fashion business (22). The clothing category showed the highest results in the average credits (2.8), class hours (3.8), the number of classes offered by the clothing construction field (7.6), and the percentage of the classes that offer clothing construction education out of all major classes offered by the clothing department (19.9%). The educational contents of clothing construction area were classified into 8 different categories of: basic theory and sewing, clothing construction, flat pattern, draping, tailoring and advanced clothing construction, pattern CAD, sewing science and apparel manufacturing process, and clothing construction for special needs. Among these categories, the draping category constituted 21.7% as the largest part. In addition, the distribution of classes offered by 4 academic years were analyzed into 8 different categories.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.21 no.6
• /
• pp.760-766
• /
• 2018

The present study investigates the effect of PMMA and BN content on microstructure, mechanical and dielectric properties of silicon nitride($Si_3N_4$) ceramics in $Y_2O_3-Al_2O_3$ additive system. The total additive content was fixed at 8 wt.% and the amount of PMMA varies from 0 to 40 wt.% and BN varies from 0 to 36 wt.%, respectively. The crystalline phases of the samples were determined by X-ray diffraction analysis. All the sintered sample shows complete transformation of ${\alpha}$ to ${\beta}-Si_3N_4$ during the sintering process indicated that the phase transformation was unaffected by the PMMA or BN content. However, the microstructure shows that the residual porosity increased with increasing PMMA and BN content. In addition, the flexural strength and the dielectric constant decrease with addition of PMMA and BN due to the residual porosity. This article provides empirical study of design parameters for $Si_3N_4$-based radome materials.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.45 no.1
• /
• pp.136-154
• /
• 2021

'Slow fashion' has become a hot issue in the fashion world as fast fashion has caused environmental and ethical problems. This study synthesized the characteristics of slow fashion from preceding studies and organized them into four characteristics (craftsmanship, nature-friendly attitude, localism, and pursuit of exclusive value). This study compared designers, John Alexander Skelton and Geoffrey B. Small with four characteristics. First, both designers sought craftsmanship based on tailoring, but Skelton focused on the eco-friendliness of materials, and Small emphasized the development of high-quality fabrics. Second, we found a nature-friendly attitude in both designers, but unlike Skelton, which maintains nature-friendliness in the process of clothing production, Small showed this characteristic through presentations. Third, both designers revealed localism through their affection for the fabrics and culture of each country. Moreover, Small extended its meaning to respect minority tastes. Finally, both designers pursued exclusive values through collections under the themes of class problem, and gender conflicts. However, Skelton melted these topics into British culture and revealed them indirectly versus Small who showed sensitive topics directly in the collections. This study will provide the foundation for analyzing designers through the characteristics of slow fashion, and suggests directions that slow fashion designers should move towards.

• Journal of KIISE:Software and Applications
• /
• v.31 no.6
• /
• pp.716-727
• /
• 2004

Component-based software development (CBD) technology has been widely accepted as a new effective paradigm for building software systems with reusable components, consequently reducing efforts and shortening time-to-market. Hence, components should provide standard or common functionalities in a domain, yielding a higher level of reusability. Especially, micro-level variability within the commonality should also be modeled so that a product member-specific business logic or requirement can be supported through component tailoring or customization The importance of commonality and variability (C&V) analysis has been emphasized in several CBD methods, but they lack of well-defined systematic process, detailed instructions, and standard artifact templates. As the result, the development of components has been carried out in ad-hoc fashion, depending on developer's experience. In this paper, we propose a systematic process and work instructions to design components. The process consists of phases and their activities and each activity is specified with detailed instructions and artifact templates in order to facilitate effective development of components. To verify a feasibility of the propose method, a case study in a banking domain and comparison and assessment between the proposed method and other methods are additionally provided. With proposed processes and instructions, reusability and efficiency of developing components can be better supported.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.10
• /
• pp.89-100
• /
• 2018

The precedent study stage of defense programs is a project stage that is conducted to support the determination of an efficient acquisition method of the weapon system determined by the requirement. In this study, the FTA/FMEA technique was used in the safety analysis process to identify elements to be conducted in the precedent study stage and a methodology for deriving the key review elements through conceptualization and tailoring was suggested. To supplement the key elements derived from the existing research, it is necessary to analyze various events that may arise from key elements. To accomplish this, the HAZOP technique for safety analysis in other industrial fields was used to supplement the results of kdy element derivation. We analyzed and modeled the execution procedure by establishing input/output information and association with the key elements of the precedent study stage derived by linking HAZOP/FTA/FMEA techniques. In addition, performance maturity was evaluated for performance of precedent study, and a risk-based response manual was generated based on inter-working information with key elements with low maturity. Based on the results of this study, it is possible to meet the performance, cost, and schedule of the project implementation through application of the key elements and procedures and the risk management response manual in the precedent study stage of the defense program.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.4 no.1
• /
• pp.111-130
• /
• 2002

This study performed a structural questionnaire survey and non-structural interview of the ladies apparel manufacturers in Daegu on the qualification for the employees, skills required for job performance, job training, automatic manufacturing systems, and the use of computer. The results are as follows. 1. Almost all of the apparel manufacturing systems were Pair System, except one Line System in one company. In terms of outsourcing, most of the manufacturers answered “yes,” and in 1998 the outsourcing process was sewing, but in the year 2002, outsourcing has been increased :12 manufacturers(57.1%) outsourcing most of the processes except patterning, 3(14.3%) outsourcing the finish of sewing. 2. The workforce of 1998 and that of 2002 shows a significant difference(P＜. 01) between office work and management. The number of office workers has decreased from 15 down to 5.3 people. On the other hand, that of the management has slightly increased from 5.3 to 9.2 people. The number of the manual workers has decreased from 32.2 to 28.7 people. And the number of tailoring and patterning workers has slightly decreased, but the number has increased in sewing from 3.7 to 7.0 people. 3. The wage of an employee shows a significant difference between a sewing assistant(P＜. 01) and a production manager(P＜. 05), and the wage of a sewing assistant, in particular, has slightly raised from ￦905,000 to ￦1,054,000. 4. The qualifications required of employees are “cooperative human relations”(30.8％), “diligence,” and “ability for job analysis”(26.9％), and “positive thinking” (15.4％) in 1998, and “ability for job analysis”(38.5％), “cooperative human relations”(34.6％), and “positive thinking” (15.4％) in 2002. The areas for job openings are significantly different(P＜. 01) depending on the year. Job openings in the design section has increased from 1(3.8％) to 16 manufacturers (61.5％), and decreased in tailoring section from 22(84.6％) to 2 manufacturers(7.7％). Job openings in the sewing section have increased form 2(7.7％) to 6 manufacturers (23.1％). In terms of sex of the employees, there is a significant difference(P＜. 001). 19 companies(73.1％) wanted “male” in 1998, but 8 companies(30.8％) answered that they want “female” and 17 companies(65.4％) answered that “it does not matter.” About the educational background, there was a significant difference between the years. The number of the companies that want junior college graduates with an associate degree has increased(15 companies(57.7％). There was a significant difference(P＜. 05) in major of the employee. The number of the companies that want fashion majors has increased from 5(19.2％) to 20(76.9％). 5. In terms of job skills required, there was no significant difference. In 1998, “production skills” (46.2％) and “ability for job analysis” (26.9％) were required, and in 2002, “ability for job analysis” (42.3％) and “emotional skills” (26.9％). 6. In regard to training for job skills, “fashion professional training” has slightly decreased from 65.4％ in 1998 to 46.2％ in 2002, however, “training for job analysis” has slightly increased from 30.8％ in 1998 to 46.2％ in 2002, which indicates the fact that “fashion professional training” and “ability for job analysis” have been emphasized. 7. The number of the manufacturers purchased apparel CAD has increased from 1(3.8％) to 3(11.5％), and the number of the manufacturers that have no plan for purchase has increased from 16(61.5％) in 1998 to 15(57.7％), still taking up a big proportion. 8. About the use of computers in manufacturing, there is a significant difference(P＜. 05). The number of the manufacturers using computer has increased from 5(19.2％) to 15(57.7％) and that of the manufacturers which do not use computers has decreased from 17(57.7％) to 8(30.8％). 9. In the interviews with the owners of the manufacturers, they pointed that schools should give more weight on practical training courses, the invitation of experts in the specific field, complex production systems, training courses for sewing, field trip courses, and furthering specialty education, personality and vocational education.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.154-155
• /
• 2012

The promise of nano-crystalites (nc) as a technological material, for applications including display backplane, and solar cells, may ultimately depend on tailoring their behavior through doping and crystallinity. Impurities can strongly modify electronic and optical properties of bulk and nc semiconductors. Highly doped dopant also effect structural properties (both grain size, crystal fraction) of nc-Si thin film. As discussed in several literatures, P atoms or radicals have the tendency to reside on the surface of nc. The P-radical segregation on the nano-grain surfaces that called self-purification may reduce the possibility of new nucleation because of the five-coordination of P. In addition, the P doping levels of ${\sim}2{\times}10^{21}\;at/cm^3$ is the solubility limitation of P in Si; the solubility of nc thin film should be smaller. Therefore, the non-activated P tends to segregate on the grain boundaries and the surface of nc. These mechanisms could prevent new nucleation on the existing grain surface. Therefore, most researches shown that highly doped nc-thin film by using conventional PECVD deposition system tended to have low crystallinity, where the formation energy of nucleation should be higher than the nc surface in the intrinsic materials. If the deposition technology that can make highly doped and simultaneously highly crystallized nc at low temperature, it can lead processes of next generation flexible devices. Recently, we are developing a novel CVD technology with a neutral particle beam (NPB) source, named as neutral beam assisted CVD (NBaCVD), which controls the energy of incident neutral particles in the range of 1~300eV in order to enhance the atomic activation and crystalline of thin films at low temperatures. During the formation of the nc-/pm-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. In the case of phosphorous doped Si thin films, the doping efficiency also increased as increasing the reflector bias (i.e. increasing NPB energy). At 330V of reflector bias, activation energy of the doped nc-Si thin film reduced as low as 0.001 eV. This means dopants are fully occupied as substitutional site, even though the Si thin film has nano-sized grain structure. And activated dopant concentration is recorded as high as up to 1020 #/$cm^3$ at very low process temperature (＜ $80^{\circ}C$) process without any post annealing. Theoretical solubility for the higher dopant concentration in Si thin film for order of 1020 #/$cm^3$ can be done only high temperature process or post annealing over $650^{\circ}C$. In general, as decreasing the grain size, the dopant binding energy increases as ratio of 1 of diameter of grain and the dopant hardly be activated. The highly doped nc-Si thin film by low-temperature NBaCVD process had smaller average grain size under 10 nm (measured by GIWAXS, GISAXS and TEM analysis), but achieved very higher activation of phosphorous dopant; NB energy sufficiently transports its energy to doping and crystallization even though without supplying additional thermal energy. TEM image shows that incubation layer does not formed between nc-Si film and SiO2 under later and highly crystallized nc-Si film is constructed with uniformly distributed nano-grains in polymorphous tissues. The nucleation should be start at the first layer on the SiO2 later, but it hardly growth to be cone-shaped micro-size grains. The nc-grain evenly embedded pm-Si thin film can be formatted by competition of the nucleation and the crystal growing, which depend on the NPB energies. In the evaluation of the light soaking degradation of photoconductivity, while conventional intrinsic and n-type doped a-Si thin films appeared typical degradation of photoconductivity, all of the nc-Si thin films processed by the NBaCVD show only a few % of degradation of it. From FTIR and RAMAN spectra, the energetic hydrogen NB atoms passivate nano-grain boundaries during the NBaCVD process because of the high diffusivity and chemical potential of hydrogen atoms.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.320-320
• /
• 2016

Nanocrystalline Carbon thin films have numerous applications in different areas such as mechanical, biotechnology and optoelectronic devices due to attractive properties like high excellent hardness, low friction coefficient, good chemical inertness, low surface roughness, non-toxic and biocompatibility. In this work, we studied the comparison of pure DC power and pulsed DC power in plasma sputtering process of carbon thin films synthesis. Using a close field unbalanced magnetron sputtering system, films were deposited on glass and Si wafer substrates by varying the power density and pulsed DC frequency variations. The plasma characteristics has been studied using the I-V discharge characteristics and optical emission spectroscopy. The films properties were studied using Raman spectroscopy, Hall effect measurement, contact angle measurement. Through the Raman results, ID/IG ratio was found to be increased by increasing either of DC power density and pulsed DC frequency. Film deposition rate, measured by Alpha step measurement, increased with increasing DC power density and decreased with pulsed DC frequency. The electrical resistivity results show that the resistivity increased with increasing DC power density and pulsed DC frequency. The film surface energy was estimated using the calculated values of contact angle of DI water and di-iodo-methane. Our results exhibit a tailoring of surface energies from 52.69 to $55.42mJ/m^2$ by controlling the plasma parameters.