• Journal of the korean Society of Automotive Engineers
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• v.6 no.3
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• pp.45-54
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• 1984

Bending strength of an internal gear tooth is discussed as tooth form factor taking into account the actual stress magnitude. Stress analysis was carried out by the finite element method(FEM) for the calculation of tooth form factor of an internal gear. This paper also investigated the influences of number of teeth and addendum modification coefficient of the internal gear and the influences of number of teeth, addendum modification coefficient, pressure angle, radius of rounding of tooth tip, and bottom clearance coefficient of the pinion-shaped cutter on tooth form factor of internal gear. Generalizing the resultant data, a simple formula for the tooth form factor of an internal gear was derived for the calculation of tooth bending strength of an internal gear.

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.66-78
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• 2010

Objective : This study was designed to investigate the possibility of AR for chronic renal injury. Methods : The author first investigated the expression levels of DNA by inducing of chronic renal injury. Then, the author investigated the effects of AR on chronic renal injury induced by combination treatment with Adriamycin and cisplatin in terms of changes in body weights and renal tissues, urine volume, BUN and creatinine levels, creatinine clearance and histopathological changes in renal tissues. Total expression levels of 546 genes were elevated or lowered by induction of chronic renal injury. Genes of which whose expression levels were elevated by induction of chronic renal injury were related to the PPAR signaling pathway and fatty acid mechanism, etc. Genes of which expression levels were lowered by induction of chronic renal injury were related to the neuroactive ligand-receptor signaling pathway. Results : Oral administration of AR restored renal mass which was reduced by induction of chronic renal injury. AR also restored creatinine clearance and lowered serum BUN level. In histopathological observation, the AR group has a tendency to prevent tissue damages as shown in the chronic renal injury group. Conclusions : AR can be used to treat patients with chronic renal injury although further study will be needed to elucidate the exact mechanisms in the efficacy of AR on chronic renal injury.

• The Journal of Internal Korean Medicine
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• v.41 no.6
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• pp.1191-1199
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• 2020

We studied the effect of Korean medicine treatment on the clearance of vancomycin-resistant enterococcus (VRE) colonization and on improvement in symptoms in a stroke patient. The patient was continuously followed up with stool VRE cultures while being treated with herbal medicine, Chunglijagam-tang, acupuncture, and oxygen therapy. We also checked the coccygeal pressure sore condition and the oxygen levels during therapy. No VRE colonization was found after treatment and the oxygen levels and pressure sores had improved. This study proved that Korean medicine treatment could be effective for the clearance of VRE colonization and improvement of symptoms.

• Fire Science and Engineering
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• v.29 no.2
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• pp.33-38
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• 2015

For the purpose of high-pressure and suction of fixed amount, the development of ultra-high pressure rotating helical gear positive displacement pump with no clearance had been proceeded. The CFD analysis was performed to verify the internal pressure and the discharge flow velocity of the pump. Accordingly, a flow analysis were performed by FVM technique and we were unable to obtain a successful result since the fluid domain is separated because the grid is not configured in a row in FVM flow analysis of the fully enclosed type without clearance. Because of these problems, the flow analysis was performed by MPS method which grid configuration is not needed and the internal pressure and the discharge flow velocity of the pump were confirmed through the MPS flow analysis. At 1,000 rpm rotation speed of the rotor, the minimum internal pressure of the pump was 19.5 bar, maximum pressure was 44.6 bar and average pressure was 33.9 bar. And the minimum discharge flow velocity was 64.5 m/s, maximum discharge flow velocity was 84.8 m/s and average discharge flow velocity was 76.1 m/s. Through this study, we could confirm that MPS method was more suitable than FVM method in terms of flow analysis with no clearance. In addition, the relationship of the flow velocity according to the change of ultra-high pressure rotating helical gear positive displacement pump could be identified through this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.575-576
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.571-572
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• 2011

• The Korean Journal of Nuclear Medicine
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• v.22 no.1
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• pp.33-37
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• 1988

Salivary scan and stimulated salivary clearance of $^{99m}Tc-pertechnetate$ was performed in 11 pateients with $Sj\"{o}gren$ syndrome (group I), 4 patients with rheumatoid arthritis (group II), 8 patients with non-connective tissue diseases (group III) and 9 normal controls. Stimulated salivary clearances of pertechnetate of normal controls, group II and group III were in normal range (over 16.5 ml/min) and that of patients with $Sj\"{o}gren's$ syndrome was significantly reduced (11.1 ml/min).

• Genomics & Informatics
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• v.8 no.1
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• pp.1-8
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• 2010

Serpin peptidase inhibitor, Clade B (ovalbumin), Member 5 (SERPINB5), also known as maspin, is a potent tumor suppressor gene. It has correlations with many tumor cells, from pancreas cancer to breast cancer, so it is possible that it may also affect liver cancer. There has also been a report that SERPINB12, a gene placed right next to SERPINB5, is expressed in liver. For this study, 32 polymorphisms were identified in SERPINB5 by direct DNA sequencing, and 11 of them were selected to be tested with a larger scale subjects. The association of the 11 SERPINB5 polymorphisms with Hepatitis B virus (HBV) clearance, hepatocellular carcinoma (HCC) occurrence and the onset age of HCC were analyzed. There were no significant associations found between 11 SERPINB5 polymorphisms and HBV clearance. In the case of HCC occurrence, one of the haplotypes (ht) showed association with HCC occurrence (OR=2.26, p=0.005, $P^{Cor}=0.05$), albeit with a low statistical power (40.8%) and haplotype frequency (0.052). Further study with a bigger sample size will be needed to clearly verify the association between ht5 and HCC occurrence.

• Genomics & Informatics
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• v.7 no.4
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• pp.195-202
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• 2009

BIRC5 (Survivin) belongs to the inhibitor of apoptosis gene family. The BIRC5 protein inhibits caspases and consequently blocks apoptosis. Thus, BIRC5 contributes to the progression of cancer allowing for continued cell proliferation and survival. In this study, we identified eight sequence variants of BIRC5 through direct DNA sequencing. Among the eight single nucleotide polymorphisms (SNPs), six common variants with frequencies higher than 0.05 were selected for larger-scale genotyping (n=1,066). Results of the study did not show any association between the promoter region polymorphisms and the clearance of hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) occurrence. This is in line with a previous study in which polymorphisms in the promoter region does not influence the function of BIRC5. Initially, we were able to detect a signal with the ＋9194A>G, which disappeared after multiple corrections but led to a change in amino acid. Similarly, we were also able to detect an association signal between two haplotypes (haplotype-2 and haplotype-5) on the onset age of HCC and/or HCC occurrence, but the signals also disappeared after multiple corrections. As a result, we concluded that there was no association between BIRC5 polymorphisms and the clearance HBV infection and/or HCC occurrence. However, our results might useful to future studies.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.238-249
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• 1995

The gas pressure acting on the rings in internal combustion engine influences the friction and wear characteristics. Inter-ring pressure variation during engine operation results from cylinder gas flow through a piston-ring pack. The flow passages consist of ring end gaps and clearances between the ring and the piston groove. The gas flow in the clearance between the ring and the groove is directly affected by the axial motion of the ring in the groove. In this paper the asperity contact force is newly considered in the prediction of the clearence between the ring and the groove surface. This term must be taken into account physically in case that the clearance get narrow rather than asperity height between the ring and the groove surface. Finally, comparisons of calculated inter-ring gas pressures based on the analytical method are made with the measured ones. The agereement was found to be good below midium engine speed, 3000rpm. In order to obtain accurate analytical results to the extend of high rpm range, it is recommended to include oil ring motion as well as top and second ring in analytical model.