• Journal of Soil and Groundwater Environment
• /
• 제8권2호
• /
• pp.36-43
• /
• 2003

Feasibility of micellar-enhanced ultrafiltration far the removal of nitrate was investigated using cationic surfactants, cetylpyridinium chloride and octadecylamine acetate. The removal of nitrate increased as the molar ratio of surfactant increased. With the molar ratio of 3, at least 80% of nitrate was removed, while > 98% of nitrate was removed at the surfactant molar ratio of 10. Octadecylamine acetate showed higher removal efficiency of nitrate and higher rejection of surfactant than cetylpyridinium chloride because of the accessibility of nitrate to surfactant micelles due to head group of surfactant. Octadecylamine acetate turned out to be a better surfactant than cetylpyridinium chloride for micellar-enhanced ultrafiltration to remove nitrate from groundwater.

• Korean Journal of Microbiology
• /
• 제39권4호
• /
• pp.277-282
• /
• 2003

Bacteriophage P4 ost2 which is the P4 mutant suppressing sir mutations of Bacteriophage P2, was isolated as a plaque-former by plating P4 ash8 sid 71 kmr intS on the lawn of P2 sir3 lysogen. P4 ost2 turned out to be the P4 mutant suppressing sir mutations of P2 in one-step growth experiments.

• Transactions of the Korean Society of Automotive Engineers
• /
• 제20권2호
• /
• pp.64-69
• /
• 2012

Head injury is one of the most common cause of deaths in car-to-pedestrian collisions. To reduce the severity of such injuries, many international safety committees have performed headform impact test for pedestrian protection. In this paper, an adult headform impactor model is developed based on the finite element (FE) method and validated through the numerical simulation. The skin material of headform impactor is known as polyvinyl chloride skin (PVC) and its material was assumed as viscoelastic. The viscoelastic parameters of headform skin are identified by a series of trial and error methods. The new developed FE adult headform impactor is verified by the drop test and FE JARI adult headform impactor provided by Madymo program.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• 제5권4호
• /
• pp.53-58
• /
• 2006

IHRA Pedestrian Working Group has investigated and analyzed the current status of pedestrian-vehicle accidents in IHRA member countries. According to the results, European countries and Japan are working on new regulations to improve passive pedestrian protection on passenger cars significantly. Although IHRA proposed pedestrian test procedures, which may provide a basis of technical regulations in the future, further research and development are necessary to refine the procedures. In order to prepare and satisfy the pedestrian protection requirements, domestic passenger vehicles also should be tested. Among various safety-related studies based on accident data analysis, dealing with pedestrian head injury would be considered one of the keen interests. In this study, the pedestrian headform impact test system is developed. The developed system will be useful to carry out validation study of the test procedures through actual tests using sample vehicles, and to explore the car feasibility level prior to the use of the test methods in legislation.

• Transactions of the Korean Society of Automotive Engineers
• /
• 제15권1호
• /
• pp.106-115
• /
• 2007

In this study, first, child headform model was built up, satisfying requirement in the headform validation test. Also, for decreasing both acceleration peak and deformation, a new hood with dome shaped forming in inner panel was investigated. Next, headform impact, complying with draft of EEVC W/G 17, on the central portion of the newly proposed hood were simulated for a steel hood and three aluminum hoods with different thickness for examining the material and thickness effect on HIC value and inner panel deformation. The analysis results explained that aluminum hoods with dome shaped forming in inner panel were highly promising not only for meeting headform safety regulations but also for leading to weight savings. Finally, hood edge design technology in order to reduce pedestrian injury due to the high stiffness of beam type edge and the rigid support, was discussed. Various types of the foam filled edge were designed and their headform safety performance were evaluated. The edge structure with foam filled in upper one third of section exhibited excellent results.

• The Journal of the Acoustical Society of Korea
• /
• 제23권1호
• /
• pp.30-39
• /
• 2004

This study aims at establishing a digital signal processing technique to control 3-D sound localization, especially focusing our ores on the role of information provided by Head-Related Transfer Function (HRTF). In order to clarify the cues to control the auditory distance perception, two conventional models named Hirsch-Tahara model and auditory parallax model were examined. As a result, it was shown that both models have limitations to universally explain the auditory distance perception. Hence, the auditory parallax model was extended so as to apply in broader cases of auditory distance perception. The results of the experiment by simulating HRTFs based on the extended parallax model showed that the cues provided by the new model were almost sufficient to control the perception of auditory distance from an actual sound source located within about 2m.

• The Korean Journal of Ecology
• /
• 제4권3_4호
• /
• pp.80-92
• /
• 1981

The vegetation of Saeng-il Island was surveyed over four times from July, 1979 to May, 1981. The results obtained are summarized as follows: Plants of this island consisted of 3 foma, 28 varieties, 211 species, 203 genera, and 89 families. Evergreen broad-leaved trees consisted of 24 species, including Camellia japonica and Castanopsis cuspidata var. sieboldii. The vegetatiion of the southwest slope was more favorable than that of the northeast slope and the vegetation of other areas were negligible. Pueraria thunbergiana and Clerodendron trichotomum were predominant in the area between Yucheon-ri and Geummo-ri. Evergreen broad-leaved trees, such as Camellia Japonica, Neolitsea sencea, Castanopsis cuspidata var. sieboldii, etc. were predominated in the areas of Gulzeon-ri, Yongchul-ri and Geummo-ri. However, artificial succession to pinus thunbergii presently dominating the areas has taken place due to human interferences (for charcaol, building materials, grazing etc.). It seems to be worthy of conserving the community of Camellia japonica on the back slope of Geummo-ri and that of Castanopsis cuspidata var. sieboldii between Gulzeon-ri and Hangdo-dong. It is notceable, in particular, that Damnacanthus indicus distributed in Jeju and Dolsan islands was also discovered in this island.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• 제38권9호
• /
• pp.1019-1027
• /
• 2014

Vehicle-into-pedestrian traffic accidents show a very high mortality rate compared to their frequency of occurrence. Throughout the world, governments and insurance companies tend to establish and implement new safety standards for pedestrian protection. In order to improve the performance of pedestrian protection, the Korean government has evaluated the pedestrian safety of vehicles under the Korea New Car Assessment Program (K-NCAP) since 2007. The pedestrian protection performance has improved gradually, but it remains insufficient. A pedestrian protection system consisting of a hood lift system and a pedestrian airbag can be a solution to pedestrian safety. A pedestrian airbag design procedure based on a newly defined design scenario is introduced to reduce the head injury criterion of pedestrians. The proposed design scenario is discussed from a practical viewpoint and applied to manufacture pedestrian protection systems.

• Applied Microscopy
• /
• 제31권3호
• /
• pp.245-256
• /
• 2001

The morphological characteristics of spermatogenic cells during the spermiogenesis of Paradoxornis webbiana were studied by transmission electron microscope. Spermiogenesis of P. webbiana was divided into ten phase. The chromatin granules became fibrous granules at the Golgi phase, gradually condensed at the cap phases, condensed as a stick at the acrosomal phase, and finally, a perfect nucleus was formed at the maturation phase. The formation of sperm tail began at the early Golgi phase, and completed at the late maturation phase. In particular, the dense materials existed in the sperm neck, which is wedged between the tip of segmented columns and the first mitochondria of the middle piece. The axone in the neck were surrounded by the dense materials. The axonema in spermatozoon contains a 9+2 arrangement of microtubules: 9 doublets, and 2 central single microtubules. Mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the $15^{\circ}$ angled-helical structure. The outer membrane of mitochondria were surrounded by microtubules in plasma membrane of the sperm. The undulating membrane had a helical structure, and the sperm plasma membrane was surrounded by undulating membrane.

• The Journal of the Korea Contents Association
• /
• 제8권11호
• /
• pp.85-93
• /
• 2008

For music score recognition, several approaches have been proposed including shape matching, statistical methods, neural network based methods and structural methods. In this paper, we deal with recognition for low resolution images which are captured by the digital camera of a mobile phone. Considerable distortions are included in these low resolution images, so when existing technology is used, many problems appear. First, captured images are not stable in the sense that they contain lots of distortions or non-uniform illumination changes. Therefore, notes or symbols in the music score are damaged and recognition process gets difficult. This paper presents recognition technology to overcome these problems. First, musical note to head, stick, tail part are separated. Then template matching on head part of musical note, and remainder part is applied. Experimental results show nearly 100% recognition rate for music scores with single musical notes.