• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.9-12
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• 2005

In this study, to investigate shrinkage and cracking behavior of 120MPa UHSC, free and restrained drying shrinkage test were performed. Three strength levels(50MPa, 80MPa, 120MPa) were used and the effect of mineral admixtures(fly ash, slag) on free and restrained shrinkage was investigated. From comparing the result of pin -penetration test with the result of ring test, Time-Zero was determined as initial set. Shrinkage test results show that autogenous shrinkage of UHSC was much higher than that of HSC, VHSC and fly ash delayed cracking age in UHSC by decreasing autogenous shrinkage. Additional free concrete rings(with restraint removed) were also tested to check the influence of the geometry of the specimens on free shrinkage. And then the relationship between free shrinkage and restrained shrinkage was investigated.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.6.1-6
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• 1983

Foreign bodies in esophagus occur unexpectedly in environment, and in most cases they get removed without delay. However, because of patron's ignorance, patient's age and lack of physician's eagerness in examination, the possible presence of the foreign body is overlooked. Recently the authors had experienced a case (5 months aged male infant) of the foreign body which had been lodged at a level of the second esophageal constriction portion for 2 months.

• The Korean Journal of Ecology
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• v.8 no.4
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• pp.215-223
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• 1985

The fluctuation of old climate was studied by the analysis of radial growth in trees, since 1782. For the effects of environmental factors on the radial growth, the authors proposed the relative radial growth(Rg) concept modified the emperical equation of Fritts (1969) as follow: Yt=aebt Yt: theoretical annual ring width time t a and b: constants in different tree species Rg=Yt/Yt Rg: ratio of real radial growth to theoretical growth with age Yt: real annual radial growth Used the Rg value, the relationship between climatic conditions and the radial growth during 70 years was investigated, and the fluctuations in climate during the last 200 years with the historical records was detected.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.217-224
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• 2007

This study was to investigate the effects of enslaving on finger-tip force of other fingers on finger pressing speed. We hypothesized that the effects depend on finger pressing speed, and the fingers proximity and are larger for fingers that are closer to each other. Six healthy, right-handed subjects(age: $27.1{\pm}4.3yr$, height: $175.4{\pm}7.2cm$, weight $71.3{\pm}5.8kg$) participated in the experiment. Each finger showed no significant on task finger speed. In the tasks with two neighboring fingers (e.g. middle and ring finger tasks), the index and middle fingers showed larger forces than the other neighboring fingers. During the index and little finger tasks, the enslaving force magnitude decreased with distance to the task finger (i.e. index finger enslaving force was the smallest during the little finger task).

• Journal of the Korean Wood Science and Technology
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• v.26 no.4
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• pp.20-25
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• 1998

Radial variation of crystalline state in a stem of Chamaecyparis obtusa E. was examined by x-ray diffraction analyses. Relative crystallinity and degree of crystallite orientation showed significant differences between juvenile and adult wood. That is, Relative crystallinity increased with increasing the age from pith to about 20th annual ring, after which it reached a more or less constant value. On the other hand, degree of crystallite orientation decreased outward from pith to about 10 years and presented almost a constant value thereafter. Crystal width by Scherrer's equation did not show any significant differences between juvenile and adult wood. Therefore, it was considered that crystallinity index and degree of crystallite orientation by x-ray diffraction method could be used for evaluating wood quality.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.133-141
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• 2015

Age and growth of redlip mullet, Chelon haematocheilus were determined using samples collected in Han River estuary of Korea from June, 2013 to May, 2014. Age was determined from sagital otoliths and Annul marks were formed in January once a year. In addition, spawning season was estimated in May, thus first ring was formed 8 months. The mullets were principally composed of 0 to 3 years old and the oldest was 9 years old. Relationship between standard length (SL) and total weight (TW) were $TW=0.0124SL^{3.0133}$($r^2=0.9931$). The Von Bertalanffy growth parameters estimated were $L_{\infty}$ 61.3, $W_{\infty}$ 3,230.6, K 0.29/year, $t_0$ - 0.05 year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.302-308
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• 1998

The growth of the purple sea urchin, Anthocidaris crassispina, has been investigated using reproduction plates as a chararter of the age determination. The samples were collected on the coast of Daepo, in the southern part of Cheju Island from August, 1995 to July, 1996. Monthly growth of test diameter mainly occurred from December to March. The obvious growth, however, were not observed between April and June which seemed to be the resting period. This resting period well corresponded to the time of annual ring formation which was estimated from the analysis of the marginal growth rate. The growth curve fitted well with Bertalanffy equation: $$L_t=46.65 (1-e^{-0.283(t+9.210)}),\;W_t=44.90 (1-e^{-0.283(t+9.210)})^3$$

• Archives of Plastic Surgery
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• v.42 no.6
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• pp.753-760
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• 2015

Background A number of conditions can alter a person's fingernail configuration. The ratio between fingernail width and length (W/L) is an important aesthetic criterion, and some underlying diseases can alter the size of the fingernail. Fingernail curvature can be altered by systemic disorders or disorders of the fingernail itself. Although the shape and curvature of the fingernail can provide diagnostic clues for various diseases, few studies have precisely characterized normal fingernail configuration. Methods We measured the W/L ratio of the fingernail, transverse fingernail curvature, hand length, hand breadth, and distal interphalangeal joint width in 300 volunteers with healthy fingernails. We also investigated whether age, sex, height, and handedness influenced the fingernail W/L ratio and transverse fingernail curvature. Results In women, fingernail W/L ratios were similar across all five fingers, and were lower than those in men. The highest value of transverse fingernail curvature was found in the thumb, followed by the index, middle, ring, and little fingers. Handedness and aging influenced transverse fingernail curvature, but not the fingernail W/L ratio. Fingernails were flatter on the dominant hand than on the non-dominant hand. The radius of transverse fingernail curvature increased with age, indicating that fingernails tended to flatten with age. Conclusions Our quantitative data on fingernail configuration can be used as a reference range for diagnosing various diseases and deformities of the fingernail, and for performing reconstructive or aesthetic fingernail surgery.

• Journal of Conservation Science
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• v.9 no.1
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• pp.48-52
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• 2000

A hundred wooden foundation piles were found underground during reconstruction for Heungreamun after removing ex-Chosunchongdokbu (ex-Government General of Chosun) building, which was built in 1916, at Kyungbok Palace in Seoul. It is known that larch piles had been collected from the Yaru area near Mt. Baekdu (Changbai). in North Korea. We examined 15 piles for identification of the species and their tree-ring structure. The species is identified as Larix gmelini by microscopic observation. Average diameter of the piles was 27 cm and average age 103 years. We obtained 151 year tree-ring chronology. However, we could not date the exact cutting years because there was no reference chronology yet. When we can obtain chronologies from living trees near the Yaru area, we could make a absolute and longer chronology for studying past history and environments around Mt. Baekdu.

• Mycobiology
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• v.38 no.4
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• pp.249-255
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• 2010

We identified Lacrymaria velutina of the Coprinaceae in Korea. The unusually large and sturdy fruiting body, fibrillose to fibrillose-scaly cap and stalk without a volva with an obscure superior hairy ring zone or hairy annulus, and blackish brown, warted spores distinguished this species from closely related Psathyrella species. An illustrated account of the microscopic traits is presented. Fruiting bodies with obtusely hemispherical caps, 2.5~6 cm, becoming convex with age; surface dry, densely fibrillose-scaly with split margin; stipe, 4.5~6 cm, equal, hollow, fibrillose, dry, whitish above the superior ring zone, light brown below; crowded gills, adnexed, dark black at maturity. Pileipellis typically cellular with the gill edge appearing white and beaded. Blackish brown basidiospores that discolor in concentrated sulfuric acid. Spores elliptical, warted, $9\sim11{\times}6\sim8{\mu}m$, with prominent snout-like germpores. Cheilocystidia abundant, $57\sim68{\times}19\sim25{\mu}m$, and narrowly elongated clavate, often clustered in threes or fours. Pleurocystidia rarely present, $45\sim47.5{\times}12\sim13{\mu}m$, and clavate to utriform. This trait distinguishes our sample as L. velutina from other Psathyrella spp. of the Coprinaceae, which have smooth spores. This taxon was clarified by the observation that Psathyrella spores fade in concentrated sulfuric acid. A molecular phylogenetic study revealed that our specimen was Lacrymria velutipes, which is closely related to Lacrymaria lacrymabunda. Moreover, those two species are clearly distinguishable from other Psathyrella species, which agreed with the morphologically distinctive traits described above. We believe that this is the first report of this taxon, which has not been described in Korea.