• Journal of Korean Society of Steel Construction
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• v.14 no.5 s.60
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• pp.657-664
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• 2002

This paper described the ultimate strength and deformation limit of the new uniplanar T-joints in cold-formed square hollow sections. In the configuration of the new T-joint, only a branch member is orientated to a chord member at 45 degrees in the plane of the truss. This study focused on the branch-rotated T-joints that were governed by chord flange failure in previous studies. Test results of the T-joint in cold-formed square hollow sections revealed a deformation limit of 3%B for $16.7{\leq}2{\gamma}(=B/T){\leq}33.3$ and $0.27{\leq}{\beta}(=b1/B){\leq}0.6$. The existing strength formulae for traditional T-joint were determined and a new yield-line model for the branch-rotated T-joint proposed. Finally, the strength formula on the yield-line analysis was compared with test results and the application range of the proposed formula recommended.

• Journal of Korean Society of Steel Construction
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• v.17 no.5 s.78
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• pp.581-591
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• 2005

This paper proposes a design formulae that evaluates the design strength of T-joints made of cold-formed square hollow steel sections with longitudinal branch plate. The T-joints had a configuration that a branch member used to longitudinal plate to the main chord in the plane. This study focused on the branch plate T-joints governed by the main chord flange failure mode among the experimental results. Based on the test results of the longitudinal branch plate T-joint in the square hollow sections, the ultimate strength on the T-joints was defined as 1.5 times the load at 1% B the strength of joints that governed the serviceability in control for $16.7{\leq}2\gamma(B/T){\leq}31.3$ and $0.20{\leq}{\beta}(b1/B){\leq}0.75$. Existing yield line models for normal T-joints were investigated to be the main chord flange failure for the branch plate T-joint, and this proposal design formula was based on the theory of the yield line model. Finally, the value of the finite element method compared with the value of the test and theory for the T-joints verified the validity of the design formulae.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.245-250
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• 2011

In the present study, we carried out a seropositive survey of Neospora (N) caninum and Toxoplasma (T) gondii in cattle at northern area of Gyeongnam province, Korea. Serum sample was obtained from Holstein cattle (n=248, 44 farms in 5 counties) and Korean indigenous cattle (n=120, 23 farms in 4 counties). All 368 sera were tested for antibodies to N. caninum and T. gondii by an enzyme-linked immunosorbent assay (ELISA). Seropositive of N. caninum at farm and heads were 41.8% (28/67) and 12.8% (47/368), respectively. Twenty-five cattle (6.8%) were seropositive to T. gondii, and eighteen (26.9%) of 67 studied farms had cows seropositive to T. gondii. The seroprevalence of Holstein cattle was much higher than that of Korean indigenous cattle. There was no apparent association of T. gondii seropositivity with age, while the seropositivity for N. caninum was associated with cattle age. The farm of cattle above the age of 5 years (16.8%) was more infective than less than 4 years (9.3%). This is the first report on seroprevalence of N. canium and T. gondii in Holstein and Korean indigenous cattle in Gyeongnam, Korea.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.251-258
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• 2011

This study was performed to determine the prevalence of Theileria sergenti (T. sergenti) in cattle reared in eastern areas of Gyeongbuk province by PCR. Among 443 samples collected from 42 cattle farms, 96 (21.7%) samples from 13 (31.0%) farms were positive for T. sergenti. By regions, 87 (26.6%) out of 327 cattle in Gyeongju, 8 (9.5%) out of 84 cattle in Pohang, and 1 (3.1%) out of 32 cattle in Ulleung were positive for T. sergenti. T. sergenti infection in dairy cattle (27.9%) was significantly higher than that in Korean cattle (9.4%, P<0.0001). Accordingly, Korean cattle were more resistant to T. sergenti infection. Prevalence of T. sergenti in cattle was increased with age (P<0.0001). The infection rate in cows (23.3%) was significantly higher than that in bulls (5.0%, P<0.01). Seasonally, prevalence of T. sergenti in cattle was highest in autumn (32.7%, P<0.01). Prevalence of T. sergenti in grazing cattle (66.7%) was significantly higher than that in non-grazing cattle (15.8%, P<0.0001). Since prevalence of T. sergenti infection is high in cattle reared in eastern areas of Gyeongbuk province, survey on other hemoparasites and appropriate control programs need to be established in this region.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1813-1817
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• 2007

The present work presents plastic limit load solutions for piping branch junctions with local wall-thinning, based on detailed three-dimensional (3-D) and small strain FE limit analyses using elastic-perfectly plastic materials. Three types of loading are considered; internal pressure, in-plane bending on the branch pipe and in-plane bending on the run pipe. The wall-tinning located on variable area of the piping branch junction is considered. A wide range of piping branch junction and wall-thinning geometries are considered. Comparison of the proposed solutions with FE results shows good agreement

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.3
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• pp.21-24
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• 1981

A simple optial fiber Y-branch is fabricated using micro - torch and fusion splicer. Tapered end of two fibers - in -contact is spliced with another fiber. Total insertion loss is 26dB and optical power branchi ng ratio is 0.98. Using fiber Y-branch, an UTDR with simple optical system is realized The resolution of the OTDR is $\pm$ 5m in length and t 0.5 dB/km in loss coefficient.

• Fire Science and Engineering
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• v.21 no.1 s.65
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• pp.98-105
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• 2007

On this study, we verified the possibilities of making T-branch pipe forming with carbon steel pipes and stainless steel pipes used by common FEM Program(ABAQUS) which are widely used in the fire protection and building construction fields. In this kind of T-branch pipe forming works, in principle, the seamless pipe is used. If the pipe has the seam, the forming face must be the opposite side of the seam. The forming works are carried out by a truncated cone shaped plug. We found that the face slope and the length of plug are the most important factor in pipe forming. Based on the results of forming analyses, we proposed the minimum height and thickness of pipe branch forming.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.251-255
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• 2009

TThis survey was carried out to investigate the prevalence of the antibody for bovine paratuberculosis (Johne's disease) in dairy cattle in Seosan-Taean area. From February to August in 2009, 254 M.RT. samples were collected from 57 farms in the regions and enzyme immuno-sorbent assay (ELISA) was conducted. Among 254 samples, 13 (5.1%) M.R.T. samples of 3 (5.2%) farms were positive by ELISA. In regional analysis, 1 (3.1%) of 34 farms in Seasan and 2 (8.6%) of 23 farms in Taean were positive in ELISA. According to the raising scale of dairy farms, the farm with below 30 heads showed the higher positive rate (2 out of 3 positive farms) than the farms with over 30 heads (1 out of 3 positive farms).

• Fire Science and Engineering
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• v.21 no.2 s.66
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• pp.36-41
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• 2007

In this study, we determined TBP(T-branched pipe) would be available in Fire Safety Codes with strength analyses. A common FEM Program(ABAQUS) was used as analyses method, and the analyses results were confirmed by strength tests of the T-branch pipe. As a result, we concluded that the T-branch pipe can be used safely. Further more, we determined what kind of stainless steel pipe can be used in place of carbon steel pipe(KS D 3507). The stainless steel pipe name Is KS D 3576(stainless steel pipe) 10S, so they can be applied for piping in fire protection system.

• Journal of Mechanical Science and Technology
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• v.20 no.5
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• pp.717-727
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• 2006

The present study experimentally investigated the effect of flow direction and other flow parameters on two-phase flow distribution of refrigerants at a T-junction, and also suggested a prediction model for refrigerant in a T-junction by modifying previous model for air-water flow. R-22, R-134a, and R-410A were used as test refrigerants. As geometric parameters, the direction of the inlet or branch tube and the tube diameter ratio of branch to inlet tube were chosen. The measured data were compared with the values predicted by the models developed for air-water or steam-water mixture in the literature. We propose a modified model for application to the reduced T-junction and vertical tube orientation. Among the geometric parameters, the branch tube direction showed the biggest sensitivity to the mass flow rate ratio for the gas phase, while the inlet quality showed the biggest sensitivity to the mass flow rate ratio among the inlet flow parameters.