• Bulletin of the Korean Mathematical Society
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• v.49 no.2
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• pp.285-293
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• 2012

In this paper, we investigate the hypersurface M in a unit sphere with constant k-th mean curvature and two distinct principal curvatures, and characterize such a hypersurface.

• Bulletin of the Korean Mathematical Society
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• v.39 no.4
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• pp.681-685
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• 2002

It is shown that, an immersion of n-dimensional compact manifold without boundary into (n + 1)-dimensional Euclidean space, hyperbolic space or the open half spheres, is a totally umbilic immersion if for some r, r =2, 3, …, n the r-th mean curvature Hr does not vanish and there are nonnegative constants $C_1$, $C_2$, …, $C_{r}$ such that (equation omitted)d)

• Journal of the Korean Mathematical Society
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• v.61 no.1
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• pp.183-205
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• 2024

In this paper, for an m-dimensional (m ≥ 5) complete non-compact submanifold M immersed in an n-dimensional (n ≥ 6) simply connected Riemannian manifold N with negative sectional curvature, under suitable constraints on the squared norm of the second fundamental form of M, the norm of its weighted mean curvature vector |H_f| and the weighted real-valued function f, we can obtain: • several one-end theorems for M; • two Liouville theorems for harmonic maps from M to complete Riemannian manifolds with nonpositive sectional curvature.

• Clinics in Shoulder and Elbow
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• v.11 no.1
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• pp.37-40
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• 2008

Purpose: We wanted to evaluate the normal glenoid size of Koreans in their 7th and 8th decades by conducting Computed tomographic (CT) studies. Materials and Methods: The CT images were obtained from the normal scapulae of the patients (mean age: 68.8) who had humeral fracture. A display workstation version 2.0.73.315 was used to measure the scans to determine the maximal superoinferior (SI) and anteroposterior (AP) diameters of the glenoid vault. Results: The average diameters of curvature of the glenoid were 31.2 mm (range: 27 to 34 mm) in the superior-inferior direction and 26.1mm (range: 22 to 31mm) in the anterior-posterior direction. Conclusion: This study showed the normal glenoid size of Koreans and it is different from the size that the international literature reported. It should be an important factor for the treatment of fracture or in designing arthroplasty implants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.474-482
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• 2015

This study aims to investigate the patterns and incidence rates of morphological deformities during artificial fingerling production of blackhead seabream (BSB, Acanthopagrus schlegeli) juveniles by visual and soft X-ray observations of BSB juveniles (n=881) collected from four industrial hatcheries. Using both methods, we observed seven types of external deformity ($11.2{\pm}4.4%$) and eight types of skeletal deformity ($53.4{\pm}5.1%$). Lordosis occurred in all hatcheries with the highest frequency and the mean frequency was $13.1{\pm}4.4%$ (24.5% in total abnormal) by soft X-ray. Although they had a similar standard length (SL), juveniles with lordosis had a significantly lower condition factor and body weight than normally developed juveniles (P<0.05); normal distribution curves of histogram of body proportions, i.e., body height (BH)/head length (HL) and trunk (=SL-HL)/BH, indicated differences between normally developed juveniles and those with lordosis. In addition, 59% of juveniles with lordosis had vertebral curvature of less than $20^{\circ}$, generally at the $17^{th}$ vertebrae. It is expected that the above results will be used as basic data necessary for determining the cause of lordosis and for developing techniques to prevent this symptom in the fingering production industry of BSB juveniles.

• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.217-223
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• 1988

A cross-sectional survey was conducted to determine the prevalence rate of scoliosis in elementary, middle and high school boys in May 1988. The study population included 1,393 male students in Pusan ; 463 students of 4th grade in two elementary schools, 543 students of 1st grade in one middle school and 387 students of 1st grade in one high school. The students of elementary school were screened with inspection by two physicians at the same time and the students of middle and high schools were screened with both inspection by the same physicians and 70mm chest X-ray. Positive students in any one of the two screening tests were measured for height and body weight and asked for the shoulder side on which he carries the school bag. The angle of curvature on X-ray film was measured by Cobb's method. The number of positive students in any one of the two screening tests were 15(3.2%) in elementary schools, 174(32.0%) in middle school and 92(23.8%) in high school. However, positive rates in both tests were only 2.2% for the middle school students and 2.6% for the high school students and among these students 1.1% out of total middle school students and 2.3% of high school students had a curvature equal to or greater than $5^{\circ}$ of Cobb's angle on 70mm chest X-ray film. There was a statistically significant association between the direction of spinal curve and the shoulder side on which one carries school bag among positive students in both screening 1.sts (p<0.05) Mean height and body weight of 281 positive students in any one of two screening tests were compared with the Korean standard for the same age. Mean weight of elementary school students was nearly the same as the standard weight but the height was slightly shorter than the standard. However, both mean height and weight of the middle school students were lower than the standard while those of the high school students were higher. The prevalence rate of scoliosis for the 2nd and 3rd grades of high school is presumed to be higher than that of the 1st grade of high school and the rate for girls will be even higher than the rate for boys of the same age. Thus, scoliosis seems to be an important school health problem. To prevent scoliosis, it is recommeded to reduce the weight of school bag, educate the students to keep a right posture and exercise periodically.