• The Korean Journal of Air & Space Law and Policy
• /
• v.25 no.2
• /
• pp.113-137
• /
• 2010

The international community has done a lot of effort to improve the aviation safety. The new high technologies, systems and development of navigation equipments considerably improved the level of aviation safety. However, the aviation accident rate has been showing unchanged status without the decline since 1980. It means it is difficult to secure enough safety by the existing efforts to improve the aviation safety, eventually needs new methods for the accident prevention. With this in mind, the nations interest new methods that can consider a countermeasure by realizing potential risk factors before fatal accidents. In other words, that is to analyze and share the safety information collected from accidents by establishing aviation safety information system. To establish international aviation safety information system, each country's aviation accident incident reporting systems are need to be established. Also aviation safety data taxonomy is need to be standardized. Then, aviation users will communicate the information efficiently. This study investigates and considers each country's aviation accident incident database taxonomy for the analysis of the aviation data and the necessary prevention activity. This will contribute to a better international aviation safety and strengthen the country's aviation diplomacy.

• Archives of design research
• /
• v.19 no.5 s.67
• /
• pp.55-64
• /
• 2006

As digital systems were introduced to automotive design in the mid 1980s, the design process has adopted many digital programs to save time compared to the conventional hand drafting. Digital technology was introduced not only to satisfy the reeds of the global environment, as the number of automobiles exported to many different parts of the world has increased, but also to save time and effort in developing several models of quality automobiles. Therefore, every automotive manufacturer in the world has expanded its virtual reality(VR) studio to establish visualization systems that visualize automobiles in the actual size and a co-operation system that enables simultaneous feedback from all of its design studios around the world. Unlike the existing design reviewing methos, the new improved feedback system is assessed as a reasonable method to evaluates and understand how the automobiles are actually manufactured in simulation. It is especially helpful when advanced products and concept cars require fast results. Other strengths of the new system include shorter development period, cost efficiency, no more manual labor, various designs within a short period of time, and realistic visualization of concepts. Large-scale products, including automobiles, need to be projected in the actual size and high clarity through the Power-wall System and are examined in a virtual space called a Cave. Therefore, it took much time to establish digital infrastructure. An infrastructure would constantly require system improvement and performance enhancement, but it is certain that now is the right time for the take-off to utilizing the strengths of digital design and improve the weaknesses. In this respect, this study provided an understanding of the importance of digital design based on digital reinforcements and examined an effective utilization of digital technology for an efficient development of automobiles in the future.

• KIISE Transactions on Computing Practices
• /
• v.22 no.11
• /
• pp.619-624
• /
• 2016

Social-aware video displays not only the relationships between characters but also diverse information on topics such as economics, politics and culture as a story unfolds. Particularly, the speaking habits and behavioral patterns of people in different situations are very important for the analysis of social relationships. However, when dealing with this dynamic multi-modal data, it is difficult for a computer to analyze the drama data effectively. To solve this problem, previous studies employed the deep concept hierarchy (DCH) model to automatically construct and analyze social networks in a TV drama. Nevertheless, since location knowledge was not included, they can only analyze the social network as a whole in stories. In this research, we include location knowledge and analyze the social relations in different locations. We adopt data from approximately 4400 minutes of a TV drama Friends as our dataset. We process face recognition on the characters by using a convolutional- recursive neural networks model and utilize a bag of features model to classify scenes. Then, in different scenes, we establish the social network between the characters by using a deep concept hierarchy model and analyze the change in the social network while the stories unfold.

• Journal of Korean Library and Information Science Society
• /
• v.48 no.4
• /
• pp.429-448
• /
• 2017

The purpose of this study is to present the development direction of future reading education by examining the characteristics of reading materials within the high school textbook developed as the 2015 revised curriculum. For this purpose, reading materials of high school textbooks were analyzed in Korean language, mathematics, English, integrated science, and integrated social studies. The analysis criteria of reading materials were subject type, purpose, and student activities. As a result of the study, reading materials on various themes such as humanity, liberty, culture, environment, and district were presented in the integrated society and integrated science textbook of the 2015 revised curriculum. In particular, the Korean language curriculum was composed of a unit called "reading one book in one semester". However, most reading materials have no guidance on reading effective or reading direction, and lack of reading materials and information for extended reading. The reader's reading of the textbook was found to be simply supplementing the learning content of each unit or presenting fragmentary cues for conceptual purposes. This suggests that there is a lack of awareness of students' interest in reading, internalization of reading, and extension of reading. In this paper, we suggest supplementary materials of reading materials for expanding the high school textbooks, and explore the developmental relationship between textbooks and reading education through suggestions on aspects of textbook composition and teaching methods.

• Journal of Nutrition and Health
• /
• v.23 no.2
• /
• pp.135-147
• /
• 1990

This study was devised to observe the cytotoxic activities of garlic extracts against various cancer cells, that is, murine leukemic lymphocyte(L1210 and P388) and human rectal(HRT-18) and colon cancer cells(HCT-48 and HT-29) in vitro, and murine ascitic tumor cell(S-180) in vivo. Each cell-line except S-180 was cultured in medium containing serial concentration of the garlic extract in vitro. Inhibitory effect n the growth rate of the cancer cells was stronger in extracts of petroleum ether than that of ethanol. A lipid soluble compound in the extracts of garlic was cytocidal to murine leukemic cells, human rectal and colon cancer cells in vitro. The growth rates of the cancer cells in medium containing garlic extracts were inhibited gradually to a significant degree in proportion to the increase of the extract concentration. The cytotoxic activity of garlic active fraction from TLC was about 2.3 times more potent than that of crude garlic extract, one unit of cytotoxic activity against L1210 cells being equivalent to 4.2$\mu\textrm{g}$ and 1.8$\mu\textrm{g}$ from the crude garlic and active fraction, respectively. The Rf value of the active fraction on silica-gel TLC was 0.18 in condition that petroleum ether/ethyl ether/acetic acid mixture(90:10:1, v/v/v) was used as a developing solvent. The survival times of mice inoculated with S-180 cells were extended about 1.5 to 2 times in the groups treated with garlic extract(through i.p. and oral administration) compared with their control group(no garlic extract treatment). Observations were carried out on S-180. Ethanol extracts of garlic injured markedly tumor cells within 3 hours after injection.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.7
• /
• pp.86-91
• /
• 2016

To solve the problem of the excessive error caused by using a single value for the shielding effect of the neutral line of an electric power distribution line in the calculation of the voltage it induces in a telecommunication line, the general expression that was previously developed to reflect the mechanism of voltage induction by a distribution line with multiple grounds is employed in this paper to represent the relationship between the leakage current rates at each ground pole. In this way, the formula for calculating the shielding effect of the neutral line can be factorized against the unbalanced current flowing in the neutral line, which is the root current of induction. This shielding coefficient of the neutral line is not constant, but can vary when a range of induced voltages is generated in the whole power distribution line. The calculation method developed herein reduces the error rate to one tenth of that of the existing calculation result in the case of overestimation and increases it by 14% in the case of underestimation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.9 no.1
• /
• pp.13-18
• /
• 1976

1) The variation of the reef knot strength $T_r$ and the trawler knot strength $T_\varrho$ with the angle $\varphi$ between the adjacent bars are given by $$T_r=T_{ro}-k_{r\varphi}$$ and $$T_\varrho=T_{{\varrho}o}+k_{\varrho\varphi}$$ where $T_{ro}$ and $T_{{\varrho}o}$ are values of $T_r$ and $T_\varrho$ at $\varphi=0^{\circ}$ respectively, and $k_r$ and $k_\varrho$ constants decided by the fibre materials of netting twines ($\varphi\;is\;0^{\circ}$ when the knot is pulled lengthwise). 2) The variation of the reef knot strength $T_r'$ and the trawler knot strength $T_\varrho'$ with the angle $\varphi'$ between any one bar and the plane made by the other three bars may be expressed by $$T_r'=T_{ro}{'}\varrho^{-c\varphi'}$$ and $$T_\varrho'=T_{{\varrho}o}{'}\varrho^{-c\varphi'}$$ where $T_{ro}{'}$ and $T_{\varrho}o{'}$ are values of $T_r{'}$ and $T_\varrho{'}$ at $\varphi'=0^{\circ}\;{(\varphi=45^{\circ})}$ respectively, and o is the coefficient of attenuation. 3) Knot strength of knotted netting may be expressed by the expression derived in the preyious paper, disregarding its shape and the direction of tensile loads acting on it.

• Korean Journal of Optics and Photonics
• /
• v.31 no.5
• /
• pp.213-217
• /
• 2020

In this study we report a wet-etching-based fabrication method for adiabatic optical-fiber tapers (OFTs), and describe their adiabaticity and HE₁₁ mode evolution at a wavelength of 1550 nm. The profile of the fabricated system satisfies the adiabaticity properties well, and the far-field pattern from the etched OFT shows that the fundamental HE₁₁ mode is maintained without a higher-order mode coupling throughout the tapers. In addition, the measured far-field pattern agrees well with the simulated result. The proposed adiabatic OFTs can be applied to a number of photonic applications, especially fiber-chip packages. Based on the fabricated adiabatic OFT structures, the optical transmission to the inversely tapered silicon waveguide shows large spatial-dimensional tolerances for 1 dB excess loss of ~60 ㎛ (silicon waveguide angle of 1°) and insertion loss of less than 0.4 dB (silicon waveguide angle of 4°), from the numerical simulation. The proposed adiabatic coupler shows the ultrabroadband coupling efficiency over the O- and C-bands.

• The KIPS Transactions:PartC
• /
• v.11C no.6 s.95
• /
• pp.835-842
• /
• 2004

In this paper, we have analyzed the MC-DS/CDMA system with input signal synchronized completely through adjustment of the gain in the PLL loop, by using the hybrid SC/MRC-(2/3) technique, which is said to one of the optimal diversity techniques under the multi-path fading environment, assuming that phase error is defined to the phase difference between the received signal from the multi-path and the reference signal in the PLL of the receiver. Also, assuming that the regarded radio channel model for the mobile communication is subject to the Nakagami-m fading channel, we have developed the expressions and performed the simulation under the consideration of various factor, in the MC/DS-CDMA system with the hybrid SC.MRC-(2/3) diversity method, such as the Nakagami fading index(m), $the\;number\;of\;paths\;(L_p),$ the number of hybrid SC.MRC-(2/3) $diversity\;branches\;(L,\;L_c),$ the number of users (K), the number of subcarriers (U), and the gain in the PLL loop. As a result of the simulation, it has been confirmed that the performance improvement of the system can be achieved by adjusting properly the PLL loop in order for the MC/DS-CDMA system with the hybrid SC/MRC-(2/3) diversity method to receive a fully synchronized signal. And the value of the gain in the PLL loop should exceed 7dB in order for the system to receive the signal with prefect synchronization, even though there might be a slight difference according to the values of the fading index and the spread processing gain of the subcarrier.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.4
• /
• pp.509-517
• /
• 2020

This study evaluated the importance of technical characteristics in manufacturing street furniture using 3D printing technology to suggest the direction of development of high priority 3D printing technology. The importance was analyzed by the QFD, quantified by scores and the priority of the items was summarized. As a result, the 'output size', 'shrinkage of material', and 'output angle' were derived as technical elements that should be prioritized in development and research. For verification, the design of atypical street furniture was made into a large 3D printed output and the development direction was suggested by applying the technical elements of priority during the manufacturing process. Street furniture should be designed based on functionality and stability, as well as economic efficiency, productivity, and aesthetics. Therefore, the 'output size' ensured stability by minimizing the division of parts, and the 'contractability of materials' satisfied the aesthetic and productivity by minimizing the error of form. Finally, the 'output angle' was verified by improving the quality of the output and selecting an angle with efficient and structural stability through various output angles.