• Journal of Power Electronics
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• v.13 no.1
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• pp.77-85
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• 2013

This paper proposes a new dead time compensation method of independent six-phase permanent magnet synchronous motors (IS-PMSM). The current of the independent phase machines contains odd-numbered harmonics because of the dead time and the nonlinear characteristics of the switching devices. By using the d-q-n three-dimensional vector analysis, these harmonics can be extracted at the n-axis current. Thus, the current distortion can be compensated by controlling the n-axis current of the IS-PMSM to zero. The proposed method is simple and can be easily implemented without additional hardware setup. The validity of the proposed compensation method is verified with simulations and several experiments.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.473-479
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• 2023

In this study, the dose of photoneutrons generated during radiotherapy of prostate cancer using high energy was measured using a photo-stimulated luminescence dosimeter. In addition, this study was intended to study the probability of side effects occurring in the abdomen. A medical linear accelerator capable of generating 15 MV energy, True Beam STx (Varian Medical Systems, USA) and a radiation treatment planning system (Eclipse, Varian Medical Systems, USA) were used. A human body phantom was installed on the couch of the linear accelerator, and an Albedo Neutron Optical Stimulation Luminescence Neutron Detector (Landauer Inc., IL, USA) was used to measure the photoneutron dose. The photoneutron dose value in the abdomen of VMAT and 3C-CRT was 52.8 mSv, more than twice as high as VMAT compared to 3D-CRT. During radiotherapy of prostate cancer, the probability of causing side effects in the abdomen due to light neutron dose was calculated to be 3.2 per 1,000 for VMAT and 1.4 for 3D-CRT. By studying the abdomen, which has a major side effect that can occur during radiotherapy of prostate cancer, it is expected that it will be used as a meaningful study to study the quality of life and stochastic effect of prostate cancer patients

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.387-394
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• 2022

Verotoxin-1 (VT-1) or Shiga-like toxin 1 (Stx-1) is produced by enterohemorrhagic Escherichia coli (EHEC) and is an AB5 holotoxin with a strong inhibitor of protein synthesis. VT-1 is a type 2 ribosome-inactivating protein (RIP) that has been shown to have cytotoxic and anticancer potential by inducing necrosis, apoptosis, and cell cycle arrest, making it a promising antitumor candidate. Here, we tested the cytotoxicity of VT-1 on CaCo2 and NCM425 cell lines and the results showed that VT-1 was more potent on CaCo2. Morphological changes were also evaluated on the cellular level and the results showed that VT-1 caused a decrease in viable cell count, altered cell membrane permeability, and an increase in total nuclear intensity. On the other hand, VT-1 displayed a lesser impact on mitochondrial membrane potential (MMP) and cytochrome c release. On the expression of caspases 3 and 9, VT-1 exhibited an insignificant effect on both which alongside the mitochondrial membrane potential (MMP) and cytochrome c results, might indicate that CaCo2 suffered from the necrosis process as a mechanism of cell death after exposure to VT-1.

• Journal of Ship and Ocean Technology
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• v.6 no.3
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• pp.1-12
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• 2002

In this paper the results are reported of sixty-nine lateral collision tests, which were performed to investigate the collision resistance of plates. For the tests a collision testing machine of spring-roller conveyer type was designed and fabricated. Using this machine, various plates were tested with different masses and velocities and various headers of the striker. A simple analytical method has also been developed to predict the extent of damage of struck plates due to lateral collision. In the method, it is assumed that the kinetic energy of the striker can be dissipated by the formation of yield lines and membrane tensions in the impacted plate. The calculated predictions of extent of damage using the developed method have been substantiated with the test results, which shows reasonably acceptable correlations.

• Journal of Ocean Engineering and Technology
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• v.25 no.3
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• pp.1-10
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• 2011

This paper estimates the residual longitudinal strength of a damaged double hull VLCC (Very Large Crude Carrier) under combined vertical and horizontal bending moments using Smith's method. The damage estimated in this study occurred due to collision or grounding accidents. The effects of the randomness of the yield stress, plate thickness, extent of damage, and the combination of these three parameters on the ultimate hull girder strength were investigated. Random variables were generated by a Monte Carlo simulation and applied to the double hull VLCC described by the ISSC (International Ship and Offshore Structures Congress) 2000 report.

• Journal of Genetic Medicine
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• v.20 no.2
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• pp.46-51
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• 2023

Exonic copy number variation (CNV), involving deletions and duplications at the gene's exon level, presents challenges in detection due to their variable impact on gene function. The study delves into the complexities of identifying large CNVs and investigates less familiar but recurrent exonic CNVs, notably enriched in East Asian populations. Examining specific cases like DRC1, STX16, LAMA2, and CFTR highlights the clinical implications and prevalence of exonic CNVs in diverse populations. The review addresses diagnostic challenges, particularly for single exon alterations, advocating for a strategic, multi-method approach. Diagnostic methods, including multiplex ligation-dependent probe amplification, droplet digital PCR, and CNV screening using next-generation sequencing data, are discussed, with whole genome sequencing emerging as a powerful tool. The study underscores the crucial role of ethnic considerations in understanding specific CNV prevalence and ongoing efforts to unravel subtle variations. The ultimate goal is to advance rare disease diagnosis and treatment through ethnically-specific therapeutic interventions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.550-553
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• 2000

Optimum temperature for paralytic shellfish poison (PSP) detoxofication of Enterobacter sp. CW-6 isolated from sea water and changes of contents and ingredients composition of PSP during bacterial detoxification process were investigated. Enterobacter sp. CW-6 detoxicated $61.5{\~}67.7{\%}\;and\;87.4{\~}96.8{\%}$ of initial PSP toxicity ($25.0{\~}28.5\;nmole/g$) after $5{\~}12$ days at 30 and $35^{\circ}C$, identified as optimal growth temperature, respectively. The detoxification rate of Enterobacter sp. CW-6 for crude PSP with initial concentration of 38.2 nmole/g after 8 and 12 days at $30^{\circ}C$ in the Marine broth was 88.4 and $92.7{\%}$, respectively. During bacterial detoxification process using crude toxin solution, temporary increasement of STX group was detected and identified that was derived from GTX2, 3 group. The detoxification rate of Enterobaoter sp. CW-6 on purified GTX1 and 4 with initial concentration 47 nmole/g and 37 nmole/g were more than $90{\%}$ after 12 days in the marine broth at $30^{\circ}C$. Enterobacter sp. CW-6 also showed a detoxification activity on purified GTX2 and 3, and the detoxification rate for the initial concentration 25.6 nmole/g after 12 days was $66.4{\%}$.

• Korean Journal of Veterinary Service
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• v.42 no.2
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• pp.93-112
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• 2019

Calf diarrhea is a common disease in young claves and is still a major cause of productivity and economic loss in livestock farms. Fecal samples from Korean native cattle (n=100) with diarrhea from 64 farms in Gwangju area, Korea from september 2017 to December 2018 were examined for shedding of important protozoan parasitic, viral and bacterial pathogens using culture, rapid test kit and PCR methods. Of 57 (89.1%) of the 64 Korean native cattle farms examined had samples infected with at least one of the investigated pathogens. Among 100 fecal samples, 88 samples were positive for at least one the twelve pathogens and 51 samples were simultaneously positive for two or more pathogens by culture and PCR assay. Bovine group A rotavirus (BRV) was the most common pathogen, found in 43/100 (43.0%) samples on 32/64 (50.0%) farms. Subsequently, kobuvirus (30.0%), pathogenic E. coli (29.0%), bovine parvovirus (17.0%), Giardia spp. (13.0%), Eimeria spp. (10.0%), Clostridium perfringens type A (8.0%), bovine torovirus (8.0%), bovine viral diarrhea virus (6.0%), bovine coronavirus (5.0%), bovine norovirus (2.0%) and Cryptosporidium spp. (2.0%) were detected. Nebovirus, kırklareli virus, bovine adenovirus, Salmonella spp. and intestinal parasites were not detected. Of the 72 calves sampled in this age group, 64 (88.9%) samples were positive for at least one enteropathogen. BRV was identified in 34/72 (47.2%) samples from 27/48 (56.3%) farms. Subsequently, pathogenic E. coli (30.6%), kobuvirus (29.2%), BPaV (22.2%), Giardia spp. (15.3%), Eimeria spp. (9.7%), BVDV (6.9%), Cl. perfringens type A (6.9%), BCoV (4.6%) and Cryptosporidium spp. (2.8%) were detected in fecal samples. A total of ninety-six strains of E. coli were isolated from one hundred fecal samples collected from Korean native cattle with diarrhea. The presence of stx1, stx2, eaeA, LT, STa, STb, ehxA, saa, F4, F5(K99), F6, F17, F18 and F41 genes in the isolates was investigated by PCR. Out of ninety-six E. coli isolates screened for specific genes, 30 strains E. coli were identified to harbor shiga toxin-producing E. coli (STEC) 7 (7.3%), enterohemorrhagic E. coli (EHEC) 8 (8.3%), enteropathogenic E. coli (EPEC) 6 (6.3%), enterotoxigenic E. coli (ETEC) 2 (2.1%) and STEC/ETEC hybrid 7 (7.3%). This study provides epidemiological estimates of the prevalence of Korean native cattle's enteropathogens in Gwangju area, Korea, which would be used for cattle farmers and veterinarians to select appropriate therapeutic method.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.1
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• pp.26-33
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• 2014

In this study, Non-load-carrying EH Grade steels in fillet welded joints were evaluated with both the hot spot stress method and the 1mm stress method. The thickness effect criterion for fatigue strength evaluation of welded of welded steel structures recommendations of the IIW was used to evaluate the fatigue strength of EH40 and EH36 and Both EH40 and EH36 have been compared with FAT 125 curve recommended in the IIW. Furthermore, fatigue strength of the welded tow and the ground conditions for Non-load-carrying EH36 based on the 1mm stress method has been discussed.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.541-546
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• 1997

There are two conserved regions with a significantly high amino acid sequence homology among the A subunits of STX, SLTs and ricin. To produce an inactive Verotoxin-2 (VT-2), two different mutants, pE167D and pDE5A, were constructed by site-directed mutagenesis, respectively, on the basis of the previous reports that two regions lie within the active-site clefts of the A subunits of ricin and STX family. The cytotoxicity ($10^3$ $CD_{50}/ml$) of VT-2 holotoxin with E167D mutation was reduced by $10^3$-fold compared with wild-type level. In addition, VT-2 with DE5A ($Trp_{202}GlyArgIleSer_{206}$) deletion mutation showed a significantly low cytotoxicity ($10^1$ $CD_{50}/ml$), resulting in $10^5$- and $10^2$-fold reductions, respectively, compared with the wild-type and E167D mutatant. SDS-PAGE for protein samples showed a 33-kDa band corresponding to the A subunit of VT-2. These results indicate that reduction in cytotoxic activity was affected not by amount of VT-2 protein produced but by mutation.