• Korea-Australia Rheology Journal
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• v.15 no.2
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• pp.91-96
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• 2003

The sensitivity of the product to the ongoing sinusoidal disturbances of the process has been investigated in the film casting of viscoelastic polymer fluids using frequency response analysis. As demonstrated for fiber spinning process (Jung et al., 2002; Devereux and Denn, 1994), this frequency response analysis is useful for examining the process sensitivity and the stability of extensional deformation processes including film casting. The results of the present study reveal that the amplification ratios or gains of the process/product variables such as the cross-sectional area at the take-up to disturbances exhibit resonant peaks along the frequency regime as expected for the systems having hyperbolic characteristics with spilt boundary conditions (Friedly, 1972). The effects on the sensitivity results of two important parameters of film casting, i.e., the fluid viscoelasticity and the aspect ratio of the casting equipment have been scrutinized. It turns out that depending on the extension thinning or thickening nature of the fluid, increasing viscoelasticity results in enlargement or reduction of the sensitivity, respectively. As regards the aspect ratio, it has been found that an optimum value exists making the system least sensitive. The present study also confirms that the frequency response method produces results that corroborate well those by other methods like linear stability Analysis and transient solutions response. (Iyengar and Co, 1996; Silagy et al., 1996; Lee and Hyun, 2001).

• Journal of Veterinary Clinics
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• v.38 no.5
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• pp.221-224
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• 2021

A 8-year-old male Golden Retriever dog with bilateral cryptorchidism presented for evaluation of symmetric alopecia and gynecomastia. Abdominal radiography and computed tomography revealed bilateral enlargement of the testicles in the abdominal cavity. The concentrations of estradiol and testosterone in the blood were evaluated, and the results revealed a low testosterone/estradiol ratio despite a normal concentration of estradiol. For correction, cryptorchid testicles were surgically removed. Grossly, the bilateral retroperitoneal cryptorchid testicles were enlarged, firm, and spherical. On histopathologic examination, the right abdominal cryptorchid testicle was diagnosed as a Sertoli cell tumor (SCT)-Seminoma (SEM) combination. The contralateral testicle in the abdomen was diagnosed as a Sertoli cell tumor. The clinical signs of feminization were improved after surgery. To our knowledge, this is the first report of a case of simultaneous SCT on one side and SCT-SEM combination on the other side with sex hormone profiles in a dog.

• Journal of Families and Better Life
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• v.18 no.1
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• pp.231-242
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• 2000

The purpose of this study is to evaluate the trend of studies in family resource management and the contribution to family and society trough the studies since the establishment of The Korean Home Management Association. For this purpose this study analized 363 articles published in 4 journals relating to family resource management for 2 decades,. The contents are 1) an analysis to the trend of the studies classified by subject and period 2) an analysis to the ratio and trend of practical studies 3) a critic to the problems which this field of studies contains of 4) the suggestions for the future-enlargement of the information and practical education enrichment of education through the field study development of methods and contents for the study.

• Journal of Korea Multimedia Society
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• v.4 no.3
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• pp.222-229
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• 2001

Many techniques have been proposed for digital image enlargement, which use spatially neighbored pixels information in a still image. In this paper, we propose the digital image interpolation method that improves edge characteristics by selectively transposing the sub-windows of pseudomedian filter, which results in relatively better performance than others. We have simulated the proposed algorithm using Visual C++ and verified performance of the algorithm by PSNR(Peak signal Noise Ratio) and edge characteristics. Finally, we have designed the adaptive pseudomedian by using synopsys VHDL(Very high speed integrated circuit Hardware Description Language).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.2
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• pp.50-57
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• 2004

Mercurous Bromide ($Hg_2Br_2$) crystals hold promise for many acousto-optic and opto-electronic applications. This material is prepared in closed ampoules by the physical vapor transport (PVT) growth method. We investigate the effects of solutal convection on the crystal growth rate in a horizontal configuration for diffusive-convection conditions and purely diffusion conditions achievable in a low gravity environment. Our results show that the growth rate is decreased by a factor of one-fourth with a ten reduction of gravitational acceleration near y = 2.0 cm. For 0.1 $g_O$ the growth rate pattern exhibits relatively flat which is intimately related to diffusion-dominated processes. The growth rate nonuniformity is regardless of aspect ratio across the interfacial positions from 0 to 1.5. Also, the effect of a factor of the ten reduction in the gravitational acceleration is same to both Ar = 5 and 2. The enlargement in the molecular weight of B from 50 to 500 by a factor 4 causes a decrease in the maximum growth rate by the same factor, indicative of the effect of solutal gradients.

• Korean Journal of Bronchoesophagology
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• v.5 no.1
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• pp.22-29
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• 1999

Background： Infectious mononucleosis is a disease precipitated by Epstein-Barr virus(EBV) in mostly children, some seronegative adolescents and young adults comprising clinical symptoms such as fever, lymphadenopathy, and pharyngitis as well as laboratory findings such as hetero-phil antibodies and atypical lymphocytosis. It is confirmed by serologic test for EBV. Materials and Methods： A retrospective evaluation of 26 patients who diagnosed with infectious mononucleosis was peformed through the analysis of typical symptom, sign and laboratory findings. Results : Infectious mononucleosis occurs mostly at 3 to 10 years (74.9%), common symptoms and signs are fever, cervical lymphadenopathy, tonsillar enlargement and exudate. Positive ratio of atypical Lymphocyte(>10%) and hetrophil antibodies are 61.5%, 35.2% respectively, it is less diagnostic. EBV-viral capsid antigen(VCA) IgM are positive in all cases, so it is most diagnostic findings. Conclusion： Infectious mononucleosis should be considered as a cause of cervical lymphadenopathy and pharyngotonsillitis in children and young adults, the assessment of EBV-VCA IgM is necessary for the diagnosis.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.11
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• pp.960-966
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• 2016

This paper proposes a new concept of a soft and wearable upper-limb exoskeleton. A novel actuation principle, called the twisted string actuation principle, is implemented to make it lightweight, soft, and therefore easily wearable. Its power transmission mechanism and harness are designed to be soft and wearable, yet have enough control accuracy for rehabilitation. In addition to force transmission optimization, a speed enlargement mechanism is newly introduced in order to increase the contraction speed of the twisted string actuation mechanism by sacrificing the unnecessarily large gear reduction ratio of the twisted string mechanism. A prototype has been tested for mirroring therapy, and the feasibility of the proposed mechanism has been shown through a sufficiently accurate tracking performance.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.3
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• pp.213-222
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• 1999

On condition that opening located at high shear strength position in H-shaped steel beams with web opening, beams are structurally to be frailed so necessity and efficiency of vertical reinforcement to add horizontal reinforcement already published ahead study. Up to the present study of web opening beams, limited one opening which located in comparatively small shear strength position. But frequently opening area is enlargement by necessity, so width of opening is larger by limit of depth or increasing number of opening. This study carry out experiment to make efficient reinforcing method about strength and deformation of steel beams with web openings. Parameters of this study are openings location, ratio of opening width within opening height and various reinforcing types.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.82-91
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• 2003

Experiments to investigate the mixing performance of unlike doublet impinging jets are conducted. Reynolds number of simulants used in this study rages from 1.0 to 1.5 Cold flow test is performed to investigate the hydrodynamic effect and spray of the impinging jets are collected locally and calculated by using Rupe's mixing efficiency equation. Momentum exchanges and relative velocity ratio between two jets are taken as the main parameter to represent the effect of enlargement of the orifice diameter. As diameter ratio increases, the corresponding momentum ratio where maximum mixing efficiency occurs and relative velocity at the maximum mixing efficiency ranges 0.6 to 0.7, respectively. Penetration depth can be taken as a prominent parameter to estimate the mixing efficiency.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.37-43
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• 1999

The image analyser was used for the measurement of the morphological changes of the spermatogenic cells and seminiferous tubules in the pheasant during the breeding and non breeding season. 1. The seminiferous tubules were enlarged 2.57 times during the breeding season than during the non breeding season. Only Sertoli cells and spermatogonia in the seminiferous tubules can be found during the non breeding season. 2. There is no significantly difference in the ratio of nucleus area against that of cell size in the spermatogonium between breeding and non breeding season. The ratio of area was 28.71% and 29.11%, respectively. However, the enlargement of spermatogonium was noticed during the non breeding season. 3. The highest value of the ratio of the nucleus area against that of cell size among the germ cells was measured 37.40% in the pachytene phase of the spermatocyte during the breeding season. 4. The ratio of nucleus area against that of cell size in the spermatid was 22.53%.