• Journal of Power Electronics
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• v.18 no.6
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• pp.1720-1728
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• 2018

This paper proposes a novel soft starting algorithm by using PWM inverter technique to control an amplitude of the motor starting current at a single-phase induction motor (SPIM). Traditional SPIM starting methods such as a Split-Phase, Capacitor-Start, Permanent-Split Capacitor (PSC), Capacitor-Start Capacitor-Run (CSCR), basically cannot control the magnitude of starting current due to the fixed system structures. Therefore, in this paper, a soft starting algorithm based on a proportional resonant (PR) control with a variable and constant frequency is proposed to reduce the inrush current and starting up time. In addition, a transition algorithm for operation modes is devised to generate a constant voltage and constant frequency (CVCF). The validity and effectiveness of the proposed soft starting method and transition algorithm are verified through experimental results.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.12
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• pp.1742-1750
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• 2015

As a novel approach for disease control and prevention, nutritional modulation of the intestinal health has been proved. However, It is still unknown whether branched-chain amino acid (BCAA) is needed to maintain intestinal immune-related function. The objective of this study was to determine whether BCAA supplementation in protein restricted diet affects growth performance, intestinal barrier function and modulates post-weaning gut disorders. One hundred and eight weaned piglets ($7.96{\pm}0.26kg$) were randomly fed one of the three diets including a control diet (21% crude protein [CP], CON), a protein restricted diet (17% CP, PR) and a BCAA diet (BCAA supplementation in the PR diet) for 14 d. The growth performance, plasma amino acid concentrations, small intestinal morphology and intestinal immunoglobulins were tested. First, average daily gain (ADG) (p<0.05) and average daily feed intake (ADFI) (p<0.05) of weaned pigs in PR group were lower, while gain:feed ratio was lower than the CON group (p<0.05). Compared with PR group, BCAA group improved ADG (p<0.05), ADFI (p<0.05) and feed:gain ratio (p<0.05) of piglets. The growth performance data between CON and BCAA groups was not different (p>0.05). The PR and BCAA treatments had a higher (p<0.05) plasma concentration of methionine and threonine than the CON treatment. The level of some essential and functional amino acids (such as arginine, phenylalanine, histidine, glutamine etc.) in plasma of the PR group was lower (p<0.05) than that of the CON group. Compared with CON group, BCAA supplementation significantly increased BCAA concentrations (p<0.01) and decreased urea concentration (p<0.01) in pig plasma indicating that the efficiency of dietary nitrogen utilization was increased. Compared with CON group, the small intestine of piglets fed PR diet showed villous atrophy, increasing of intra-epithelial lymphocytes (IELs) number (p<0.05) and declining of the immunoglobulin concentration, including jejunal immunoglobulin A (IgA) (p = 0.04), secreted IgA (sIgA) (p = 0.03) and immunoglobulin M (p = 0.08), and ileal IgA (p = 0.01) and immunoglobulin G (p = 0.08). The BCAA supplementation increased villous height in the duodenum (p<0.01), reversed the trend of an increasing IELs number. Notably, BCAA supplementation increased levels of jejunal and ileal immunoglobulin mentioned above. In conclusion, BCAA supplementation to protein restricted diet improved intestinal immune defense function by protecting villous morphology and by increasing levels of intestinal immunoglobulins in weaned piglets. Our finding has the important implication that BCAA may be used to reduce the negative effects of a protein restricted diet on growth performance and intestinal immunity in weaned piglets.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2968-2974
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• 2010

Nowadays, the PV systems have been focused on the grid connection between the power source and the grid. The PV inverter can be considered as the core of the whole system because of an important role in the grid-interfacing operation. An important issue in the inverter control is the load current regulation. In the literature, Proportional Integral (PI) controller, which is normally used in the current-controlled Voltage Source Inverter (VSI), cannot be a satisfactory controller for an AC system because of the steady-sate error and the poor disturbance rejection, especially in high-frequency range. Compared with conventional PI controller, Proportional Resonant (PR) controller can introduce an infinite gain at the fundamental frequency of the AC source; hence it can achieve the zero steady-state error without requiring the complex transformation and the de-coupling technique. Theoretical analyses of both PI and PR controller are presented and verified by simulation and experiment. Both controller are implemented in a 32-bit fixed-point TMS320F2812 DSP processor and evaluated on a 3kW experimental prototype PV Power Conditioning System (PCS). Simulation and experimental results are shown to verify the controller performances.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1110-1121
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• 2016

The mathematical model of a three phase PWM converter under the stationary αβ reference frame is deduced and constructed based on a Proportional-Resonant (PR) regulator, which can replace trigonometric function calculation, Park transformation, real-time detection of a Phase Locked Loop and feed-forward decoupling with the proposed accurate calculation of the inductance voltage vector. To avoid the parallel resonance of the LCL topology, the active damping method of the proportional capacitor-current feedback is employed. As to current vector error elimination, an optimized PR controller of the inner current loop is proposed with the zero-pole matching (ZPM) and cancellation method to configure the regulator. The impacts on system's characteristics and stability margin caused by the PR controller and control parameter variations in the inner-current loop are analyzed, and the correlations among active damping feedback coefficient, sampling and transport delay, and system robustness have been established. An equivalent model of the inner current loop is studied via the pole-zero locus along with the pole placement method and frequency response characteristics. Then, the parameter values of the control system are chosen according to their decisive roles and performance indicators. Finally, simulation and experimental results obtained while adopting the proposed method illustrated its feasibility and effectiveness, and the inner current loop achieved zero static error tracking with a good dynamic response and steady-state performance.

• Reproductive and Developmental Biology
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• v.32 no.1
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• pp.21-25
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• 2008

Bone marrow mesenchymal stem cells (BMMSCs) have the capacity for self-renewal and differentiation into a variety of cell types. They represent an attractive source of cells for gene and cell therapy. The purpose of this study is to direct the specific expression of the DsRed reporter gene in $Sca-1^+$ BMMSCs differentiated into a cardiomyogenic lineage. We constructed the prMLC-2v-DsRed vector expressing DsRed under the control of the 309 tp fragment of the rat MLC-2v 5'-flanking region. The specific expression of the DsRed reporter gene under the transcriptional control of the 309 bp fragment of the rat MLC-2v promoter was tested in 5-azacytidine healed-$Sca-1^+$ BMMSCs over 2 weeks after the prMLC-2v-DsRed transfection. The prMLC-2v-DsRed was specifically expressed in the $Sca-1^+$ BMMSCs with cardiomyogenic lineage differentiation and it demonstrates that the 309 bp sequences of the rat MLC-2v 5'-flanking region is sufficient to confer cardiac specific expression on a DsRed reporter gene. The cardiac-specific promoter-driven reporter vector provides an important tool for the study of stem cell differentiation and cell replacement therapy in ischemic cardiomyopathy.

• Journal of The Korean Dental Society of Anesthesiology
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• v.12 no.1
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• pp.17-23
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• 2012

Background: This study evaluated pulp vitality of anterior permanent teeth using pulse oximetry (PO), which is already used for monitoring of patient's $SpO_2$ and pulse rates (PR). Also we compared with ice tests and electric pulp test (EPT). Methods: 9 teeth, endodontic treated, were selected as non-vital teeth group. 17 vital teeth were selected as control group. Our aim is to compare sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ice test, electric pulp test and pulse oximetry, respectively. Pulse oximetry has two test results, $SpO_2$ and pulse rates. Also we calculated correlation and statistical significances by Pearson's test between EPT and pulse oximetry. Results: Sensitivity, specificity, PPV, NPV were calculated on each tests. Ice test has results of 1.00, 0.89, 0.94 and 1.00, respectively. EPT has results of 0.94, 0.78, 0.89 and 0.88 respectively. $SpO_2$ has results of 0.94, 1.00, 1.00 and 0.90, respectively. PR has results of all 1.00. Conclusions: PO showed relatively accurate, stable and objective results on both $SpO_2$ and PR. Percentage of ability of accurate diagnosis for vital teeth is 94% for ice test, 89% for EPT, 100% for $SpO_2$ and PR. Percentage of ability of accurate diagnosis for non-vital teeth is 100% for ice test, 88% for EPT, 90% for $SpO_2$ and 100% for PR. In additions, PR could be more accurate and significant tests than $SpO_2$.

• Toxicological Research
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• v.22 no.4
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• pp.431-438
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• 2006

The object of this study was to obtain acute toxicity information (single oral dose toxicity) of lyophilized water extract of Puerariae Radix (PR) in both male and female mice. In order to investigate the 50% lethal dose $(LD_{50})$, approximate lethal dosage (ALD), test substances were once orally administered to female and male ICR mice at dose levels of 2000 and 0 (control) mg/kg (body wt.) according to the recommendation of KFDA Guidelines [2005-60, 2005]. The mortality and body weight changes, clinical signs and gross observation were monitored during 14 days after dosing. Organ weight and histopathology of 12 principal organs were measured. As the results, we could not find any mortality, clinical signs, body weight changes and gross findings except for PR extracts unrelated sporadic findings. In addition, no abnormal changes related PR extracts treatment on the organ weight and histopathology of principal organs were detected except for some sporadic findings including hyperplasia of lymphoid follicles in the popliteal lymph nodes and spleen as pharmacological effects of PR extracts. The results obtained in this study suggest that the PR extracts does not cause any toxicological signs except for pharmacological effects of enhancement of Immune system. The $LD_{50}$ and ALD of PR extracts in both female and male mice were considered as over 2000 mg/kg because no mortalities were detected up to 2000mg/kg that was the highest dose recommended by KFDA and Organization for Economic Co-Operation and Development.

• Korean Journal of Acupuncture
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• v.23 no.2
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• pp.137-154
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• 2006

Results: 1. In the AlPR-HA group, the incidence of arthritis and arthritis index were significantly decreased. 2. In the AlPR-HA group, the levels of $IL-6,\;IFN-{\gamma},\;TNF-{\alpha},\;IL-1{\beta},\;IgG,\;IgM,\;Anti-collagen\;II$ in serum of the CIA mouse were significantly decreased. 3. In the AlPR-HA group, the levels of $IFN-{\gamma:,\;IFN-{\gamma}\;/IL-4$ in spleen cell culture of the CIA mouse were significantly decreased. 4. In the Hematoxylin and eosin stain, the cartilage destruction and synovial cell proliferation were decreased in the AIPR-HA group. 5. In the Masson's trichrome stain, the collagen fiber expressions were similar with that of the Normal group. 6. In the AlPR-HA group, the expression ratio of $CD3e^+$ to $CD19^+$ cell and $CD4^+$ to $CD8^+$ cell were similarly maintained as Normal group in the CIA mouse lymph nodes. 7. In the AlPR-HA group, $CD3e^+/CD69^+$ cells in the CIA mouse joint and $CD11a^+/CD19^+$ cells and $CD11b^+/Gr-1^+$ cells in the CIA mouse lymph nodes were significantly decreased. 8. In the AIPR-HA group, $CD4^+/CD25^+$ cells were significantly decreased in the CIA mouse spleen cell and were similarly maintained as Normal group in the CIA mouse lymph nodes. Conclusions: These results suggest that AlPR-HA at 51'36 has an effect to control synovial cell proliferation and cartilage destruction in rheumatoid arthritis.

• The Journal of Korean Medicine
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• v.36 no.2
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• pp.21-35
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• 2015

Objectives: The purpose of this study was to examine the efficacy of Picrorrhizae Rhizoma (PR) aqueous extracts on the formalin-induced paw chronic inflammation in mice. Methods: PR extracts (500, 250 and 125mg/kg) or distilled water (DW) were orally administered once a day for 10 days to formalin-injected chronic inflammatory mice. The paw thicknesses and volumes were measured daily and the paw wet-weight and histological profiles were conducted at termination with paw tumor necrosis factor (TNF)-${\alpha}$ contents measurement. The anti-inflammatory effects of PR extracts were compared with dexamethasone. Results: In DW treated control group, the paw thickness, paw wet-weights and paw TNF-${\alpha}$ contents were markedly increased. Severe chronic inflammation signs such as severe fibrosis, the formation of necrotic debris, and infiltration of inflammatory cells were detected in histopathological observations. However, these formalin-induced changes were dramatically decreased by treatment of dexamethasone and all three different dosages of PR extracts. The anti-inflammatory effects of PR at highest dose were slighter than that of dexamethasone, but it did not show any harmful effects on the body weight contrary to dexamethasone. Conclusion: These results suggest that PR extracts have safe and favorable effects on formalin-induced chronic inflammation.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.2
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• pp.66-77
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• 2012

Objectives: This study was designed to investigate the effects of PR on ovarian tissue in PCOS rats through measurement of morphological and histo-pathological observations, ovarian size. In addition, effects on expression levels of Insulin like Growth Factor Receptor(IGFR) were also investigated to elucidate related mechanisms. Methods: PCOS was induced by single intermuscular injection with ${\beta}$-Estradiol 17-Valerate(EV) in female rats. Normal group(NOR, n=8) were injected with sesame oil and administrated hard food for five weeks. Control group(CTL, n=8) were injected with EV and administrated hard food for five weeks. CR group(n=8) were injected with EV and administrated hard food mixed CR for five weeks. Then, we measured weights of body and ovary, uptakes of food and water. And we observed morphological and histo-pathological changes of ovary, levels of IGFR. Results: In this experiments, single injection of Estradiol Valerate(EV) induced suppression of weight gain, formation of cysts, increase of IGFR expression. Oral administration of PR prevent decrease of ovarian size significantly. Further more, formation of cystic follicles induced by EV injection is suppressed by PR treatment. Conclusions: These results suggest PR can be used for patients with PCOS to prevent formation of cystic follicles and malfunction of ovary.