• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.7
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• pp.296-303
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• 1986

The active filter of current injection type is the device which eliminates the harmonics in ac line by injecting the harmonic compensating current into the ac side. And its harmonic reduction performance is entirely dependent on the control scheme of the current-fed inverter and the harmonic compensating current becomes the PWM wave by the inverter. This PWM compensating current can be determined by selecting the switching function properly which eliminates the harmonics up to any order with using no independent sources. The new injection current model is derived by the proposed method which is called the optimized injection method. The overall characteristics of the proposed method are investigated through digital computation and the feasibility is proved with experimental results obtained from the Z-80 microcomputer control of the active filter.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.2
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• pp.32-42
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• 1998

Lean burn gasoline engine is recognized as a promising way to meet better fuel economy. Lean burn engine is classified into port injection and direct injection(DI), DI is more active technique for improving fuel economy with ultra-lean operation, Nowadays, port injected lean burn engine has been produced by many Japan maker. Also, DI engine is also possible for production owing to improvement in control technique of spray, flow air fuel ratio. DI engine uses either homogeneous stoichiometric mixture or stratified mixture by controlling injection timing to be early or late respectively. HM(homogeneous mixture) is worse than SM(stratified mixture) in view of ultra-lean operation in partical load and Nox reducion by using EGR control. But, HM has advanteges in cold starting and emission reduction during transient operation, This paper describes experimental variables and bench test results of HM GDI engine.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.114-122
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• 1997

Nowadays, gasoline direct injection engines are being commercialized by virtue of improvement in control technology of spray, flow, air fuel ratio. The stratified charge type has the advantage of improving lean limit. The homogeneous type has the advantage of reducing engine-out hydrocabon emissions in the first 30 seconds after a cold start, in addition, improving transient air fuel ratio control. The vaporization and mixing if injected fuel with air has to e completed in a short time and the fuel film in cylinder and on piston has to be minimized. So, the flow and injection should be well controlled. This paper surveyed the spray characteristics of gasoline direct injection by using laser equipment and the combustion characteristics of the single cylinder engine using homogeneousas-mixture type gasoline direct injection.

• Journal of ILASS-Korea
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• v.20 no.3
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• pp.195-201
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• 2015

This study discusses a fuel injector test bench containing a mechanical type fuel supply system for heavy duty diesel engine. The main focus of this study was to evaluate the design stability of the test bench, which basically measures the injector durability of a multi-hole heavy duty injector by using pure diesel as a test fuel. In this experiment, diesel spray was controlled by a specially designed control box and all the experiments were carried out to measure e.g. fuel injection pressure and fuel injection quantity to understand the injection status which is interlinked with the stability factor of total test bench design. Also, the durability test was performed to understand the heavy duty operation lastingness of the designed system and the flow rate of the installed distributor pump in the fuel supply system of this studying test bench was compared with LO-1 and LO-2 pump. The results of the above mention tests revealed that the injector test bench design and control system can serve the purpose for heavy duty injector.

• Journal of Ginseng Research
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• v.17 no.1
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• pp.29-34
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• 1993

This study was undertaken to investigate the effect of red ginseng extract (5.5 mg/mouse ip) on the activities of superoxide dismutase (SOD), peroxidase and catalase in the liver of the gamma ray irradiated male mice. The experimental groups consisted of control, red ginseng extract injection group, irradiation (8 $Gy^{60}$Co) group and red ginseng extract injection after irradiation group. in red ginseng extract injection group, SOD, peroxidase and catalase activities were similar to that in the control group. In irradiation group SOD, peroxidase and catalase activities increased progressively until the 2nd day after the treatment and then decreased thereafter, whereas red ginseng extract injection after irradiation group recovered more rapidly than irradiation group. The above results suggested that red ginseng extract injection after irradiation group have the recovery effects on the activities of SOD, peroxidase and catalase after radiation injury in the liver of male mice.

• Journal of Pharmacopuncture
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• v.15 no.4
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• pp.7-14
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• 2012

Objectives: The purpose of this study is to compare the effects of bee venom pharmacopuncture (BVP) therapy according to the methods used to treat knee osteoarthritis (OA): intra-acupoint combined with intra-articular injection, intra-acupoint injection, and intra-articular injection. Methods: A total of 69 patients were recruited by the Department of Acupuncture & Moxibustion at Dong-Eui Oriental University Hospital from February 1 to July 23, 2012. The patients were assigned to 3 groups: the first group with intra-acupoint combined with intra-articular BVP Injection (the experimental group), the 2nd group with intra-acupoint BVP injection (control group II), and the 3rd group with intra-articular BVP injection (control group II). The participants were assigned in the order in which they were recruited. Treatments were done twice a week, for a total of 9 times. The effectiveness was assessed by using the visual analouge scale (VAS) and the Korea Western Ontario and McMaster Universities Osteoarthritis Index (KWOMAC). Results: All three groups exhibited significant VAS and KWOMAC effects. Moreover, the 4 week follow-up after the final treatment showed a persistence of BVP effects. However, when the groups were compared, no statistically significant differences in VAS and KWOMAC were noted, but when improvement was considered, the results showed that intra-articular injection was more effective than intra-acupoint injection. Especially, intra-acupoint combined with intra-articular injection was the most effective among the three treatments. Conclusions: Combining intra-acupoint with intra-articular injection, depending on the patient's symptoms, may produce better results when conservatively treating knee OA.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5597-5600
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• 2014

Objectives: To assess side effects on Cantharidin sodium and Shenmai injection combined with chemotherapy in treating patients with breast cancer postoperatively. Method: Patients with breast cancer receiving postoperative chemotherapy were retrospectively collected, and divided into four groups: group A with cantharidin sodium injection combined with chemotherapy; group B with Shenmai injection combined with chemotherapy; group C with both cantharidin sodium and Shenmai injection combined with chemotherapy; while group D (control group) received chemotherapy alone. All patients were administered docetaxel at a dose of $75mg/m^2$ on day 1, epirubicin hydrochloride at a dose of $60mg/m^2$ on day 1, and cyclophosphamide at a dose of $500mg/m^2$ on day 1 for 3 cycles (repeated at 21 day intervals). After ${\geq}$ three courses of treatment, quality of life and side effects were evaluated. Results: There were a total of 78 patients in this study, and the incidence of leukopenia and gastrointestinal reactions in groups A and B were lower than those in the control group and lowest in group C (p<0.05). Conclusions: Thus cantharidin sodium and Shenmai injection combined with chemotherapy reduce side effects and deserve to be further investigated in randomized clinical control trials.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.4
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• pp.247-252
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• 2016

Objective: Heparin can modulate proteins, and influence processes involved in implantation and trophoblastic development. This study aimed to assess the improvement of clinical pregnancy and implantation rates after local intrauterine injection of low-molecular-weight heparin (LMWH) in patients undergoing intracytoplasmic sperm injection (ICSI). Methods: A randomised case/control design was followed in women scheduled for ICSI. The study arm was injected with intrauterine LMWH during mock embryo transfer immediately following the ovum pickup procedure, while the control arm was given an intrauterine injection with a similar volume of tissue culture media. Side effects, the clinical pregnancy rate, and the implantation rate were recorded. Results: The pregnancy rate was acceptable (33.9%) in the LMWH arm with no significant reported side effects, confirming the safety of the intervention. No statistically significant differences were found in the clinical pregnancy and implantation rates between both groups (p= 0.182 and p= 0.096, respectively). The odds ratio of being pregnant after intrauterine injection with LMWH compared to the control group was 0.572 (95% confidence interval [CI], 0.27-1.22), while the risk ratio was 0.717 (95% CI, 0.46-1.13; p= 0.146). No statistical significance was found between the two groups in other factors affecting implantation, such as day of transfer (p= 0.726), number of embryos transferred (p= 0.362), or embryo quality. Conclusion: Intrauterine injection of LMWH is a safe intervention, but the dose used in this study failed to improve the outcome of ICSI. Based on its safety, further research involving modification of the dosage and/or the timing of administration could result in improved ICSI success rates.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.725-732
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• 2018

The vaccination for foot-and-mouth disease (FMD) is an effective way to control FMD. However, the injection of FMD vaccine causes abnormalities in pork meat by the incidence of lesions at the injection site. This study was conducted to investigate the inhibition effects of dietary bromelain, a natural protease derived from pineapple stems, on the incidence of lesions at the vaccination site on pigs. A total of 335 pigs (LYD [Landrace ${\times}$ Yorkshire ${\times}$ Duroc]; 7-week-old) were randomly allotted to two dietary treatments: control (basic diet) and bromelain treatment (diet supplemented with bromelain 1 kg/ton). The injection of FMD vaccine was conducted on 56- and 84-day-old pigs. Pigs with the bromelain treatment were fed a diet supplemented with bromelain for 14 days from 5 days before the vaccine injection. After slaughtering the pigs, the number of carcasses that had abnormal meat at the injection site of the vaccine and the amount of abnormal meat, discarded meat, and trimmings were recorded. Pork from the bromelain treated pigs had a lower incidence of abnormal meat caused by vaccine injection as well as a lower amount of abnormal meat, discarded meat, and trimmings than those of the control (p < 0.05). Our result suggests that dietary bromelain could improve the quality of pork meat by inhibiting incidence of lesions at the vaccine injection site.

• The Journal of the Acoustical Society of Korea
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• v.42 no.3
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• pp.233-242
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• 2023

In this paper, the effect of mass injection on the control of tip vortex cavitation was studied experimentally. A mass injection system for a 3D hydrofoil was designed to control the location of injection as well as the injection rate. A series of cavitation tests were carried out in a cavitation tunnel for different injection locations and rates. The cavitation behaviour was observed using a high-speed camera and the corresponding noise was measured using a hydrophone installed in the observation window. The results showed that the tip vortex cavitation was suppressed under certain conditions and the noise was reduced in some frequency bands. It was also found that there is a location where the effect of mass injection could be maximized and hence the noise reduction.