• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.34-34
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• 2014

We investigate the constraints on the matter density ${\Omega}m$ and the cosmological constant ${\Omega}{\Lambda}$ using the gravitational lensed QSO (Quasi Stellar Object) systems from the Sloan Digital Sky Survey (SDSS) by analyzing the distribution of image separation. The main sample consists of 16 QSO lens systems with measured source and lens redshifts. We use a lensing probability that is simply defined by the gaussian distribution. We perform the curvature test and the constraints on the cosmological parameters as the statistical tests. The statistical tests have considered well-defined selection effects and adopt parameter of velocity dispersion function. We also applied the same analysis to Monte-Carlo generated mock gravitational lens samples to assess the accuracy and limit of our approach. As the results of these statistical tests, we find that only the excessively positively curved universe (${\Omega}m+{\Omega}{\Lambda}$ > 1) are rejected at 95% confidence level. However, if the informations of the galaxy as play a lens are measured accurately, we confirm that the gravitational lensing statistics would be the most powerful tool.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.445-451
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• 2012

Visual changes and speed changes in curved sections of highways are more dangerous than straight sections According to the enquetes conducted by Coalition for Transportation Culture in 1999, about 78% of drivers are dissatisfied with traffic guide and safety signs, with lack of visibility being the largest reason with about 27.9% of respondents indicating it as reason for dissatisfaction. In particular, the lack of visibility during nighttime or bad weather not only threatens driver safety due to poor delivery of information, but also affects the service level of highways. Because of this a new delineation must be installed and managed to enhance driver visibility. In this research, an optimal delineation system to enhance traffic safety is presented. In this research drivers effectively obtained information on highway alignment on the curved sections using a retro-reflection type delineation system and a newly-developed internal lighting delineation system to improve safety on the highways. A statistical comparison was conducted and analysis was done for the delineation systems that enhanced visibility through primary and secondary enquaetes. As a result, inside-lighting delineator will be selected in terms of safety at the curve sections. The inside-lighting delineator was more effective than the retro-reflection delineator on visibility, the necessity of reduction of speed and will reduce the hazard at curve sections. It is anticipated that when a delineation system based on this research is installed, a reduction in the number the number and severity of traffic accidents on curved sections will be reduced. In addition this system will more effectively provide drivers with information about highway alignment.

• Tunnel and Underground Space
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• v.29 no.2
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• pp.89-107
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• 2019

Rock joints have an extremely important role in analyzing the mechanical stability and hydraulic characteristics of rock mass structures. Most rock joint parameters are generally indicated as a distribution by statistical techniques. In this research, calculation technique of Joint Center Volume (JCV) is analyzed, which is required for estimating the size distribution having the largest uncertainty among the joint parameters, then a new technique is proposed which is applicable regardless of the shape of survey window. The existing theoretical JCV calculation technique can be applied only to the plane window, and the complete enumeration techniques show the limitations in joint trace type and analysis time. This research aims to overcome the limitations in survey window shape and joint trace type through calculating JCV by using Monte Carlo simulation. The applicability of proposed technique is validated through the estimation results at non-planar survey windows such as curved surface and tunnel surface.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.6
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• pp.101-108
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• 2016

This study was initiated to minimize head injuries, which is the largest cause of increased external activity, traffic accident injuries, and death. We developed a low cost airbag that can be covered by a safety helmet based on consumer needs. The results of the survey showed that safety is the most important aspect of consumers' safety helmets. It also predicted that increasing the weight would present the biggest problem. Curved airbag cushion parts that can be attached to a helmet and the sensor part of a block type were designed. Impact analysis was performed by specifying the pressure inside the airbag and the volume of the airbag as variables.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.3
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• pp.301-312
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• 2000

This study conducted an analysis of the middle aged women whose ages are from 35 to 59 years old in order to give those ladies much external satisfaction and covered body lines. I have come to present a few characters of body types as silhouettes which resulted in the factors of the upper bodies of middle aged women. I have adopted SAS(statistical analysis system) as a data process method of this survey. The followings are the results analysis. 1. The item of height have decreased, but increased in the items of thickness among the late middle aged women. 2. The body componant factor of middle aged women are extracted as 10 items, and the rate of their cumulative contribution is 78.9%. The first is the thickness of upper body, the second is the thickness of side upper body, the third is the height of upper body, the fourth is the length of upper body the fifth is width of upper body, the sixth is the projected rate of back, the seventh is the projected rate of breast, the eighth is the squared rate of shoulder, the ninth is the crooked rate of neck, and the tenth is the upper from of breast. 3. The body types of middle aged women can be classified into 4 types, and the followings are their characters. Type 1 is a standard type as the most common body character of the middle aged women, showing the appearing rate of 42.4%. Type 2 is a semi-curved body type like the curved figure of side body, showing the appearing rate of 34.5%. Type 3 is a reverse body type with the projected breast feature of front body, showing the appearing rate of 20.9%. Type 4 is a crooked body type with a tall height and crooked neck, showing the appearing rate of 2.2%.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.476-480
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• 2020

A marine red algal species was collected from Uljin, located on the eastern coast of Korea, during a survey of marine algal flora. This alga shares the generic features of Plocamium, and is characterized by linear, flat and thin thalli with narrow axes, branches developing in alternating pairs from margins of the axes, two to four times alternately pinnately branching, linear or occasionally adaxially curved lowermost branchlets and distinctly and compactly clustered stichidia. In a phylogenetic tree based on rbcL sequences, the Korean alga nests in the same clade as P. serrulatum. The genetic distance between both sequences within the clade was calculated as 0.0-0.2%. Based on the morphological and molecular data, this Korean species is identified as P. serrulatum described originally from Taiwan. This is the first record of P. serrulatum in Korean marine algal flora.

• Journal of the Korean Home Economics Association
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• v.43 no.6 s.208
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• pp.27-35
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• 2005

The purpose of this study was to develop motorcycle wear with built-in airbag protection for enhanced comfort and fit. Based on the survey results, a motorcycle jacket was designed using. Aauto CAD. This study concentrated on the wearing comfort comparison of the motorcycle jacket developed from this research with that of and foreign goods. To evaluate the wearing comfort, 3 types of motorcycle jackets were used. The results of this study were as follows. : From an Analysis of the differences in wearing comfort, the motorcycle jacket developed proved to be more convenient than the 2 types of foreign motorcycle jackets in terms of the standing and handle grip posture. This effect was due to the curved pattern of the neckline part of the airbag. The air pressure of the airbag must be improved.

• Journal of Species Research
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• v.11 no.2
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• pp.108-116
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• 2022

During a field survey to report unrecorded Korean ciliates, we collected five anaerobic ciliate species in two samples from freshwater and marine environments. These species belong to the classes Armophorea and Plagiopylea. The morphology of these species was studied based on live observations, protargol impregnation, and scanning electron microscope. Brachonella contorta is characterized by a size of 80-100×40-60 ㎛ in vivo, a bullet-shaped body, and about 60 oral polykinetids making 360° spiral around long axis. Brachonella pulchra is characterized by a size of 80-110×50-70 ㎛ in vivo and adoral zone composed of about 40 oral polykinetids with minimal spiralization. Metopus setosus is characterized by a size of 45-70×20-30 ㎛ in vivo, about 22 ciliary rows, very long caudal cilia, and 20 oral polykinetids. Plagiopyla nasuta is a freshwater species characterized by a size of 80-120×50-60 ㎛ in vivo, striated band present, straight extrusomes, and about 70 somatic ciliary rows. The marine Plagiopyla frontata is characterized by a size of 80-120×40-60 ㎛ in vivo, an oval to ellipsoid body shape, 50-60 somatic ciliary rows, and curved extrusomes.

• Animal Systematics, Evolution and Diversity
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• v.39 no.1
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• pp.53-57
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• 2023

During a survey for the southern sea of Korea, an iphiculid crab, Pariphiculus coronatus, was newly recorded from Korea. Specimens were obtained at a depth of 109-120 m near Jejudo Island. Pariphiculus coronatus can be distinguished from congeners by the following characters: the carapace length and the carapace width subequal, the surface of carapace covered with round granules, the medial tubercles of the intestinal and cardiac region of the carapace, and the first gonopod curved in the half region and straight in the distal portion. The Korean leucosiods have 16 genera and 20 species so far. Here we provide the diagnosis and illustration of Pariphiculus coronatus.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2D
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• pp.127-134
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• 2010

Tunnel sections on the highway are different from rest of sections on the highway in terms of velocity, the number of passing cars, and vehicle density which, in particular, affect drivers' behavior before and after drivers pass through the tunnel. However, literature review reveals that former studies are too focused on quantitative indicator to consider qualitative aspects. Therefore, this paper conducts survey questionnaire and IPA (Importance Performance Analysis) to find out qualitative improvements on velocity drop on the tunnel sections. The results show as follows: First, drivers require improvements of tunnel form (length and curved form inside tunnel) which is derived from long distance tunnel. Second, experts primarily ask for amendment of geometric characteristics. With comparison of requirements of both drivers and experts, there are many differences in length of tunnel and form of curved tunnel. This also presents that drivers don't satisfy with both length of tunnel and form of curved tunnel that are provided as a part of highway design factors.