• Title/Summary/Keyword: V/f control

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New Control Scheme for AC-DC-AC Converter Without DC Link Electrolytic Capacitor (직류링크 전해커패시터 없는 AC-DC-AC 컨버터 제어에 관한 연구)

  • Kim, Joohn-Sheok;Sul, Seung-Ki
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.695-697
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    • 1993
  • In this paper, a novel concept for a static three-phase to three-phase power converter for an AC drive with an unity power factor and reduced harmonics on the utility line is presented. The power circuit consists of two back-to-back connected six-pulse bridges having only a $5{\mu}F$ ceramic capacitor in the DC link. By controlling the active power balance between two bridges, the DC link voltage can be maintained within 20V deviation from the nominal value with the small ceramic capacitor regardless of the load variation even in the unbalanced source condition.

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A Study on Effect of Flex Additions for Selecting the Process Parameters in GMA Welding processes (GMA 용접공정에서 공정변수 선정을 위한 플럭스 첨가에 관한 연구)

  • Kim, In-Ju;Kim, Jun-Ki
    • Journal of the Korean Society of Mechanical Technology
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    • v.13 no.1
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    • pp.17-22
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    • 2011
  • As the quality of a weld joint is strongly influenced by process parameters the welding process, an intelligent algorithms that can predict the bead geometry and shape to accomplish the desired mechanical properties of the weldment should be developed. In this study, prepared by ${\Phi}1.6mm$ GMA welding of metal wire nose Advice jowelui 350A 600A grade level inverter welder and DAIHEN SCR's were carried out using welding. Welding conditions were 5.5m/min wire feed rate the welding current is rapidly transmit approximately 260A, welding voltage was about 30V. CTWD a 22mm, shielding gas was Ar 20L/min and the welding speed was a 240mm/min. Using data collected during welding equipment welding current and welding voltage waveform was analyzed by measuring the volume of the transition mode. Addition of $CaCO_3$ as a loss of the spread of the weld bead dilution rate decreased, suggesting that, GMA in the overlay welding bead shape control, dilution control and may be used as a welding flux is considered. Stabilizing effect of the arc by the Ca-containing $CaF_2$, $CaCO_3$, $CaMg(CO_3)_2$, respectively, welding flux 0.1wt.% added GMA welding and weld overlay were evaluated with dilution, $CaF_2$, and $CaMg(CO_3)_2$ added to the dilution of Seemed to increase.

Patient Exposure Dose Reduction in Coronary Angiography & Intervention (심혈관조영술 및 중재술 시 환자 선량 감소방안)

  • Lim, Do-Hyung;Ahn, Sung-Min
    • Journal of radiological science and technology
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    • v.45 no.1
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    • pp.69-76
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    • 2022
  • This study, the method of reducing the exposure dose by changing the geometrical requirements among the preceding studies and the method of directly wearing a protector on the patient were used to expose the patient. A comparative experiment was conducted on the method of reducing the dose and the most effective method for reducing the exposure dose was investigated. Using the phantom, the dose of the lens, thyroid gland, and gonad gland in the 5 views most used in coronary angiography and intervention accumulated 5 times for 10 seconds at 60~70 kV, 200~250 mA as an automatic controller of the angiography system, and measured by Optically Stimulated Luminescent Dosimeter(OSLD). SID 100 cm and Cine 15 f/s as a control group the experiment was conducted by dividing the experimental group into 3 groups: a group lowered to Cine 7.5 f/s, a phantom protector, and a group lowered to 95 cm SID. As a result of the experiment, showing decrease in exposure dose compared to the control group. Lowering the cine frame may be the simplest and most effective method to reduce the exposure dose, but there is a limit that it cannot be applied if the operator judges that the diagnostic value is small or feels uncomfortable with the procedure. Conclusion as fallow reducing the exposure dose by directly wearing protector is the next best solution, and it is hoped that the conclusions obtained through this study will help reduce the exposure dose to unnecessary organ.

Analysis of whole genome sequencing and virulence factors of Vibrio vulnificus 1908-10 isolated from sea water at Gadeok island coast

  • Hee-kyung Oh;Nameun Kim;Do-Hyung Kim;Hye-Young Shin;Eun-Woo Lee;Sung-Hwan Eom;Young-Mog Kim
    • Fisheries and Aquatic Sciences
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    • v.26 no.9
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    • pp.558-568
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    • 2023
  • Vibrio vulnificus is an aquatic bacterium causing septicemia and wound infection in humans. To understand this pathogen at the genomic level, it was performed whole genome sequencing of a cefoxitin-resistant strain, V. vulnificus 1908-10 possessing virulence-related genes (vvhA, viuB, and vcgC) isolated from Gadeok island coastal seawater in South Korea. The genome of V. vulnificus 1908-10 consisted of two circular contigs and no plasmid. The total genome size was estimated to be 5,018,425 bp with a guanine-cytosine (GC) content of 46.9%. We found 119 tRNA and 34 rRNA genes respectively in the genome, along with 4,352 predicted protein sequences. Virulence factor (VF) analysis further revealed that V. vulnificus 1908-10 possess various virulence genes in classes of adherence, antiphagocytosis, chemotaxis and motility, iron uptake, quorum sensing, secretion system, and toxin. In the comparison of the presence/absence of virulence genes, V. vulnificus 1908-10 had fur, hlyU, luxS, ompU, pilA, pilF, rtxA, rtxC, and vvhA. Of the 30 V. vulnificus comparative strains, 80% of the C-genotype strains have all of these genes, whereas 40% of the E-genotype strains have all of them. In particular, pilA were identified in 80% of the C-type strains and 40% of the E-type strains, showing more difference than other genes. Therefore, V. vulnificus 1908-10 had similar VF characteristics to those of type C strains. Multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin of V. vulnificus 1908-10 contained 8 A-type repeats (GXXGXXXXXG), 25 B.1-type repeats (TXVGXGXX), 18 B2-type repeats (GGXGXDXXX), and 7 C-type repeats (GGXGXDXXX). The National Center for Biotechnology Information (NCBI) Basic Local Alignment Search Tool (BLAST) showed that the RtxA protein of V. vulnificus 1908-10 had the effector domain in the order of cross-liking domain (ACD)-C58_PaToxP-like domain- α/β hydrolase-C58_PaToxP-like domain.

Ingestive Behavior of Heifers Supplemented with Glycerin in Substitution of Corn on Brachiaria brizantha Pasture

  • Facuri, L.M.A.M.;Silva, Roberio Rodrigues;da Silva, F.F.;de Carvalho, G.G.P.;Sampaio, C.B.;Mendes, F.B.L.;Lisboa, M.M.;Barroso, D.S.;Carvalho, V.M.;Pereira, M.M.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.11
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    • pp.1584-1592
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    • 2014
  • The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of $264.83{\pm}3.83kg$ and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p<0.05), whereas the time spent on activities like rumination, idleness, trough and total chewing time were quadratically affected (p<0.05). Bite rate and number of bites/day were quadratically influenced (p<0.05). The number of bites/swallowed cud and the number of bites/minute, however, increased linearly (p<0.05). Although the time spent on each cud and number of chews per cud were not affected (p>0.05).The number of rumination periods reduced linearly (p<0.05), whereas the number of grazing, idle and trough periods, and the times per grazing, idle, rumination and trough periods were quadratically affected (p<0.05). The feed and rumination efficiencies of the dry matter, non-fibrous carbohydrates, pasture dry matter and concentrate were quadratically affected (p>0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p<0.05). Addition of glycerin in substitution of corn in supplements for animals managed on pastures does not influenced feed intake, but reduces the grazing time and increases the idle time. The supplementation also improves feed and rumination efficiencies.

Effect of Feed Additives in Growing Lambs Fed Diets Containing Wet Brewers Grains

  • Aguilera-Soto, J.I.;Ramirez, R.G.;Arechiga, C.F.;Mendez-Llorente, F.;Lopez-Carlos, M.A.;Silva-Ramos, J.M.;Rincon-Delgado, R.M.;Duran-Roldan, F.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.10
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    • pp.1425-1434
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    • 2008
  • The study was conducted to evaluate and compare the effects of feed additives on ruminal fermentation, nutrient digestibility and performance of lambs fed diets containing 60% wet brewers grains (WBG). In Experiment 1, two simultaneous trials were conducted. Fifty intact ($20.2{\pm}0.8kg\;BW$) lambs were used in a feedlot trial and 10 (rumen cannulated; $32{\pm}1kg\;BW$) in a digestion trial. The pH, volatile fatty acids (VFA) and ammonia-N in lambs were also estimated. Lambs were randomly assigned to one of five diets: i) without additives (Con), ii) with 1% bicarbonate (Bic), iii) with 1% bentonite (Ben), iv) with 33 mg/kg monensin (Mon) and v) with 200 mg/kg fibrolityc enzymes (Enz). In Experiment 2, 120 RambouilletPelibuey intact male lambs ($19.5{\pm}1.5kg\;BW$) were used in a feedlot trial and randomly assigned to four diets: i) without additives (control), ii) with 1% Bic, iii) with 33 mg/kg Mon and iv) with 1% Bic and 33 mg/kg Mon. In Experiment 1, lambs fed diets containing Bic or Mon had significantly higher final weight, DMI, ADG than other lambs. However, apparent DM, OM, CP, NDF and ADF digestibilities and ruminal individual VFA content were similar (p>0.05) among treatments. Conversely, treatmentcollection period interaction was significant for ruminal pH and NH3. In Experiment 2, lambs fed diets containing a Bic and Mon combination had significantly higher final weight, DMI and ADG. It is concluded lambs fed Bic or Mon or Bic and Mon combination had better performance characteristics than lambs on Ben or Enz.

Effect of Polyherbal Feed Supplement "Growell" during Induced Aflatoxicosis, Ochratoxicosis and Combined Mycotoxicoses in Broilers

  • Kalorey, D.R.;Kurkure, N.V.;Ramgaonkar, J.S.;Sakhare, P.S.;Warke, Shubhangi;Nigot, N.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.3
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    • pp.375-383
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    • 2005
  • An experiment was conducted to study the protective role of polyherbal feed supplement (Growell) during induced mycotoxicosis in broilers. A total of 240 Vencobb broilers were divided at day old stage into eight equal groups. Group A served as control and was given plain feed, group B, D, F and H were given Growell at 0.35 g/kg of feed. Group C, D, G and H were given dietary aflatoxin $B_1$ at 0.2 ppm and groups E, F, G and H were given ochratoxin A at 0.2 ppm in feed to study effect of Growell on individual aflatoxicosis, ochratoxicosis and combined mycotoxicosis of broilers. The chicks were given their respective feeds from 1st day to 6th week of age and were vaccinated at 7th and 28th day of age with Lasota strain of Newcastle disease virus. There was no statistically significant effect of mycotoxins individually or in combination on body weight of broilers. However, body weights were highest in group B and lowest in co-mycotoxicated group G. Feed conversion ratio was best in group B followed by A, D, F, E, H and G. Significant improvement in haemoglobin values was observed in broilers due to feeding of Growell in ochratoxin and co-mycotoxicated groups. There was no significant effect of mycotoxin treatment on PCV, TEC and TLC of broilers. Due to single and combined mycotoxicosis, there was reduction in serum total protein, albumin, cholesterol and triglyceride and rise in alkaline phosphatase, creatinine and uric acid levels. Supplementation of diets with Growell reduced the alterations induced due to mycotoxins. There was a significant rise in per cent organ weight of liver and reduction of that of spleen, bursa of Fabricius and thymus of broilers fed mycotoxins. Protection from alteration in per cent organ weight of these organ by supplementation of Growell was recorded. The observed impaired immune response and histopathological changes in liver, kidney, spleen, bursa of Fabricius and thymus of broilers given mycotoxins were protected by supplementation of Growell.

Study on Antitumor Activity and Immunomodulatory effects of Seoleosojong-tang (활어소종탕이 항종역반응에 미치는 영향)

  • Son Ki Jeong;Park Yang Chun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.1
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    • pp.137-147
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    • 2004
  • In order to evaluate the antitumor activity and immunomodulatory effects of Seoleosojong-tang(SST), studies were done. We measured the cytotoxic activity for various kinds of cancer cells, inhibitory effect on activity of DNA topoisomerase I, cell adhesion to complex extracellular matrix, survival time in ICR bearing S-180, pulmonary colonization and histological changes of lung in C57BL/6 injected i.v. with B16-F10, CAM assay, expression of CD4/sup +/, CD8/sup +/, B220/sup +/, cytokine gene in spleen cell. The results were obtained as follows: 1. In cytotoxicity against A549, HT1080, 816-F10, NCL-H661 was showed cytotoxicity as compared with control. 2. The inhibitory effect on adhesion of A549, 816-F10 to complex extracellular matrix was over 40% at 100 ㎍/㎖ of SST. 3. In DNA topoisomerase I assay, SST has inhibitory effect. 4. The T/C% was 120.8 in SST treated group in S-180 bearing ICR mice. 5. In pulmonary colonization assay, a number of colonies were decreased significantly and histological changes were showed that infiltration area of cancer cells were inhibited effectively in SST treated group. 6. In CAM Assay, SST has antiangiogenic effect. 7. On the expression of positive cell to CD4/sup +/, CD8/sup +/ and 8220/sup +/ in spleen cells, CD4/sup +/ cells were increased significantly in SST treated group. 8. Effect of SST on IL-1β gene expression in splenic cell was significantly increased as function of whole concentration. 9. The gene expression of IL-4, IL-6, IL-10, IL-12, IFN-γ, TNF-α were increased in SST treated group. From above results SST could be usefully applied for antitumor activity and immunomodulatory effects, but further research of SST should be required.

HYBRID LIGHT DUTY VEHICLES EVALUATION PROGRAM

  • Trigui, R.;Badin, F.;Jeanneret, B.;Harel, F.;Coquery, G.;Lallemand, R.;Ousten, JP.;Castagne, M.;Debest, M.;Gittard, E.;Vangraefshepe, F.;Morel, V.;Baghli, L.;Rezzoug, A.;Labbe, J.;Biscalia, S.
    • International Journal of Automotive Technology
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    • v.4 no.2
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    • pp.65-75
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    • 2003
  • A HEV evaluation program, funded by ADEME, was carried out by a group of Laboratories of different specialties in order to evaluate and compare consumption, emission and component technologies of the three first HEVs put on the market (Toyota Prius, Nissan Tino and Honda Insight). This paper presents the results obtained until now. These results show good consumption and emission performance of the tested vehicles compared to conventional ones. The energy management seems to be globally the same for the three vehicles excepting for cold stans where the Insight allows a very earlier stop of the engine compared to the Tino and especially to the Prius. A mapping of the engine consumption of the Prius and the Insight was performed in order to furnish data for the simulation models. The Permanent Magnet motors of the Prius and Tino have different number of pair poles and then different emf at a given speed. The low emf values of the Prius allow operation at high speed with less field weakening control than for the Tino. The inverters of the Prius and the Tino, controlled by a PWM at respectively 5 kHz and 7 kHz switching frequency, are made of IGBTs with high commutation performances.

The Effects of KABHANGBANG(KHB) on the Hyperthyroidism of Rats (갑항방이 백서의 갑상선기능항진증에 미치는 영향)

  • Kim, Min-Seok;Kim, Cheol-Jung;Cho, Chung-Sik
    • The Korea Journal of Herbology
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    • v.21 no.4
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    • pp.19-25
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    • 2006
  • Objectives : The aim was to study experimentally the effects of KABHANG-BANG(갑항방) on the hyperthyroidism of rats induced by sodium levothyroxine. Methods : Spargue-Dawley rats were separated into four groups. Except normal group, the other three groups were treated with sodium levothyroxine $32{\mu}g$/200g/days for 5 days by oral administration. Among the three groups, two except one(as control) were treated KHB extract 225mg/200g/days(sample A), 450mg/200g/days(sample B) for 3 days separately. T3-uptake, T3, T4, r-TSH, total cholesterol, total protein change in the Serum of rats were measured after medication of solid extract of KHB. Results : As a result of this study, in the serum T3 and T4 level were decreased in sample A and B compared to controls. The serum r-TSH, total cholesterol and total protein were increase in sample A and B compared to controls. In the serum T3-uptake content, Smple B showed significant decrease in comparison with control group, but Sample A did not show significant decrease. Conclusion : According to the above results, it is suggested that KHB is effective to cure hyperthyroidism.

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