• The Journal of the Petrological Society of Korea
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• v.17 no.1
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• pp.1-15
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• 2008

The metasedimentary rocks of the Nampo Croup consisting of metaconglomerates, metasandstones, phyllites are exposed in the area of the Daechcon beach and Maryangri, Seocheon-gun. Their typical metamorphic assemblages of Bt-Mus-Grt-Qtz (${\pm}Pl{\pm}Chl$) and Bt-Mus-Qtz (${\pm}Pl{\pm}Chl$) indicate that they have been under intermediate P/T type metamorphism and were metamorphosed to garnet zone grade of amphibolite-facies during the Daebo Orogeny. Pressure-temperature conditions of peak metamorphism estimated from geothermobarometries are $560{\sim}595^{\circ}C$, $6.9{\sim}8.2\;kb$ respectively. The results of K-Ar biotite age determination are $143.2{\pm}3.6\;Ma$, $122.6{\pm}2.4\;Ma$ and $124.8{\pm}2.4\;Ma$ and the last two ages are considered as the results of later-stage thermal perturbation. On the bases of the formation age of Daedong Supergroup of $187{\sim}172\;Ma$ (Han et al., 2006; Jeon et al., 2007) combined with the results of this study, the hypothetical model of tectonometamorphic evolution of the study area during Daebo Orogeny is proposed. Crustal thickening resulted from folding and duplexing of thrusts in the area initiated at around 175 Ma just after sedimentation of Nampo Croup. And then rapid cooling by normal faulting due to crustal extention followed immediately after the peak metamorphism to the closure temperature of biotite.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.339-344
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• 2006

The aim of this study was to examine the timing and magnitude of growth spurt in skinfold, body musle and bone related variables aligned on peak height velocity in boys and girls. In the study design, the subjects and the method were used by the cross-sectional investigation. The subjects participated in this study were 7 through 18 years of age belonged to typical primary, junior, senior high school students, and about 250 males and 250 females in each age group. The total subjects were 2,798 males and 2,762 females. All subjects of this study were lived in Pusan metropolitan city, Korea. The growth velocity magnitudes of sum of the four sites sknfold thickness, body musle and bone related variables. Velocity curve chart of physique was the smoothed according to an approximation of splines by the Sigma Plot-2001 graphic program. In this study, age at PHV of girls occurred eariler about 2 years than boys. In sum of four sites skinfold thickness, PV occurred -2 years from PHV in boys, and PV occurred +2 years from PHV in girls, respectively. In humerus breadth, two PV occurred before and after PHV in boys, whereas PV occurred -1 year from PHV in girls, respectively. In femur breadth, PFV and PHV appeared to occure the same time in boys, PV occurred -2 years from PHV in girls, respectively, In arm circumference, PV occurred after PHV in both sexes. In calf circumference, PV occurred +2 years from PHV in boys, PCCV and PHV appeared to occure the same time in girls, respectively. In magnitudes of peak velocity of body height, humerus breadth, femur breadth, arm circumference and calf circumfence, boys obtained higher than girls, on the other hand, girls obtained higher than boys in sum of four sites skinfold variable. we need to longitudinal and scientific investigation by Korean government level in adolescent growth spurt study, because childhood and adolescence achive higher positive physical education effect than the other ages.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.416-421
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• 1998

The objective of this study was to investigate the responsiveness of hypophysis and gonads to synthetic GnRH among noncycling Murrah buffalo heifers at 24 months of age. The plasma FSH, LH, estradiol and progesterone levels were measured in blood samples collected at 1 hour before and upto 18th day subsequent to the administration of GnRH ($(200 {\mu}g)$) or saline (2 ml). The pretreatment levels of plasma FSH, LH estradiol and progesterone among GnRH treated heifers (N = 6) were $11.55{\pm}0.57ng/ml$, $0.68{\pm}0.06ng/ml$, $19.84{\pm}0.82pg/ml$ and $0.45{\pm}0.07ng/ml$ respectively. A quick elevation of FSH (p < 0.01) and LH (p < 0.05) within 5 min of GnRH administration was observed in all the heifers. The peak FSH ($74.97{\pm}18.63ng/ml$) and LH ($3.09{\pm}0.54ng/ml$) level was obtained at 30 min of GnRH administration. The elevated level of plasma estradiol on 5th to 18th day, FSH on 7th to 9th day (n = 3) and the progesterone on 13th to 18th day (n = 2) of GnRH injection was obtained. The study indicates that gonads of buffalo heifers at 24 months of age are responsive of GnRH induced gonadotropin release for folliculogenesis and luteal tissue formation

• International Journal of Concrete Structures and Materials
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• v.4 no.2
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• pp.89-96
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• 2010

This paper focuses on the effect of creep on the critical compressive strain (CCS) of concrete. The strain of concrete corresponding to the peak compressive stress is crucial in the selection of the ultimate yield strength of the reinforcing bar used in reinforced concrete columns. Among the various influencing factors, such as the creep, shrinkage, loading rate and confinement, the effect of creep and shrinkage is the most significant. So far, investigations into how these factors can affect the CCS of concrete have been rare. Therefore, to investigate the effect of creep and shrinkage on CCS, an experimental (part I) and a parametric study (part II) were conducted, as presented in these papers (part I considers creep effect, part II considers effect of creep and shrinkage). In part I, experiments pertaining to the loading age, loading rate, loading duration and loading and creep levels were conducted to study the effect of these variables on the CCS of concrete. It was found that the effects of the loading rate, loading age, and level and duration on the CCS of concrete were negligible. However, it is very important to consider the effect of creep.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.128-131
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• 2004

This paper is to investigate the mock up test results of mass concrete for transfer girder using setting time difference with super retarding agent(SRA) to reduce hydration heat. According to test results, the temperature history of plain concrete without placing lift had a steep rising curvature, and plain concrete had a big temperature difference between surface and middle section of mass concrete, which may result in occurrence of temperature crack. However, considering placing method B, because setting time of middle section concrete was retarded with an increase in SRA contents, higher hydration heat temperature was observed at surface section concrete compared with that at middle section concrete at early age, which can lower the possibility of hydration heat crack. In case of placing method C, although peak temperature of hydration heat was much lower, at early age, high crack occurrence possibility of the hydration heat attributable to the big temperature difference between middle section and bottom section of concrete was expected at bottom section concrete. Therefore, the structure above the ground like transfer girder is not applicable to consider the placing method C.

• Journal of Nutrition and Health
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• v.29 no.7
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• pp.778-787
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• 1996

The purpose of present study was to assess the change of bone mineral density(BMD) and the influences of anthroopometric indices and body composition on BMD in Korean women in Taegu. Subjects were 242 healthy female in the range of 7-67 years old, were divided into 4 age groups in order to assess the influence o factors on BMD according to age. Body composition and BMD measurements of lumbar spine, femur(neck, ward's triangle, trochanter) and total body were performed by dual energy X-ray absorptiometry. The analysis indicated that BMD of most region was positively related to body weight, BMI in all groups 4(50-67years), and closely related to femurs than lumbar spine. This study found correlations between BMD and both total fat body mass and total lean body mass in group 1, 2, 3, and correlations between BMD and only total fat body mass and in group 4. But on regression models the most significant prediction of BMD throughout the skeleton was total lean body mass in group 1(7-16years)and 2(17-34years, and total fat body mass in group 3 and 4. It is concluded that the our data can be used to screen early women of low bone mass. This study confirms that one of the most effective way to prevent osteoporosis and the fractures is to maximize peak bone mass in early life and to minimize bone loss through maintaining adequate weight.

• Computers and Concrete
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• v.17 no.2
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• pp.271-280
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• 2016

This study examined the mechanical properties and adiabatic temperature rise of low-heat concrete developed based on ternary blended cement using ASTM type IV (LHC) cement, ground fly ash (GFA) and limestone powder (LSP). To enhance reactivity of fly ash, especially at an early age, the grassy membrane was scratched through the additional vibrator milling process. The targeted 28-day strength of concrete was selected to be 42 MPa for application to high-strength mass concrete including nuclear plant structures. The concrete mixes prepared were cured under the isothermal conditions of $5^{\circ}C$, $20^{\circ}C$, and $40^{\circ}C$. Most concrete specimens gained a relatively high strength exceeding 10 MPa at an early age, achieving the targeted 28-day strength. All concrete specimens had higher moduli of elasticity and rupture than the predictions using ACI 318-11 equations, regardless of the curing temperature. The peak temperature rise and the ascending rate of the adiabatic temperature curve measured from the prepared concrete mixes were lower by 12% and 32%, respectively, in average than those of the control specimen made using 80% ordinary Portland cement and 20% conventional fly ash.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.3
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• pp.293-296
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• 2000

The purpose of this study is to find the histopathological pattern of cysts. We reviewed the hospital chart, out-patient chart, roentgenogram, histopathologic report and operation report of 152 patients who had been diagnosed as cyst and treated at the department of Oral and Maxillofacial Surgery of Korea university hospital between Jan. 1, 1995 and Dec. 31, 1998. And then we studied clinically with regard to pathological classification, age and sex distribution, anatomical distribution and so on. The results were as follows : 1. In pathologic classification, radicular cyst (97cases, 64%), dentigerous cyst (35cases, 23%), odontogenic keratocyst (8cases, 5.3%) were dominant among cases of cyst. 2. The pattern of age distribution in cases of radicular cyst, dentigerous cyst and odontogenic keratocyst was similar to that found in previous studies. The peak incidence was in the second decade (27%) and third decade (29%) in overall cases. 3. The male-to-female ratio was 1.9 : 1. 4. Radicular cyst occured most frequently in the maxillary incisor teeth area, dentigerous cyst in mandibular wisdom teeth area, and odontogenic keratocyst in mandibular molar area.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.2
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• pp.278-286
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• 2009

Restaurants have two strategic levers for revenue management: duration control and demand-based pricing. Reducing dining times, especially during peak periods, can add considerable revenue for restaurants. Managing meal duration, however, can be far more complex than manipulating the price. This paper examines dining duration expectations for restaurants types(Family, Korean, Quick service restaurant), customers characteristics(gender, age, occupation, meal period, visiting frequency, dining occasion, dining companions) using an a adaptation of a price sensitivity measurement tool, naming it 'Time Sensitivity measurement tool' or TSM. The TSM is then used to derive the optimal time points, and the range of acceptable times. The results demonstrate that there is a relatively wide spread of acceptable dining duration times in family restaurant. Furthermore, the optimal time points was shorter than the mean expected dining times, which suggests that many restaurants may be able to shorten dining duration without compromising customer satisfaction. The paper explores whether demographic and dining variables have an impact on time preferences, and finds whether gender, age, meal periods, visiting frequency, and dining companion effects are significant. Specifically, women in their thirties tended to prefer a significantly longer dining times for dinner.

• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.417-424
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• 2004

Polycarboxylate type superplasticizers (PCA) with different graft chain (Polyethylene oxide) length were synthesized by Methoxypoly (ethyleneglycol)monomethacrylate (MPEGMAA) and methacrylic acid (MAA). The effects of PCA on the hydration of Ordinary Portland Cement (OPC) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. The effect of graft chain length of PCA on the hydration of OPC was different at early age, but, at long age, was similar. The ratio of relative peak intensity, (I［001］/I［101］), of Ca(OH)$_2$ compared with OPC also was reduced by PCA addition.