• Title/Summary/Keyword: Multiple injection

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A Study on the Diesel DI-HCCI Combustion Characteristics using 2-stage Injection Method (2단 분사 방식을 적용한 디젤 DI-HCCI 연소특성에 관한 연구)

  • Chung, Jae-Woo;Kang, Jung-Ho;Kim, Byoung-Soo;Kang, Woo;Kim, Hyun-Chul
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.6
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    • pp.66-73
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    • 2004
  • In this study, combustion characteristics and various performances of a Diesel fuel DI-HCCI engine using 2-stage injection method were investigated. From these researches, application ability of 2-stage injection strategy to a DI-HCCI engine was confirmed and improvement methods of performances were considered. As the results, Using 2-stage injection method, without change of engine specifications and loss of IMEP, exhaust of NOx and Smoke emissions could be reduced to about 1/3 (at 1400rpm, IMEP 6bar) compared to conventional Diesel combustion.

Comparisons between fresh and cryopreserved fat injections in facial lipofilling

  • Yang, Hyee Jae;Kang, Sang Yoon
    • Archives of Craniofacial Surgery
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    • v.21 no.1
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    • pp.15-21
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    • 2020
  • Background: Autologous fat is considered an ideal filler material, and the use of cryopreserved fat grafts is promising in terms of flexibility and efficiency. Therefore, cryopreserved fat grafts have become more common in recent years; however, their complications require further consideration. Methods: We evaluated 53 patients who underwent facial lipofilling at our institution to confirm the clinical usefulness and safety of cryopreserved fat. Fresh fat injections with or without cryopreserved fat were administered. At one or more sites, 22 patients had a single fresh fat injection, four patients had two or more fresh fat injections, 16 patients had one fresh fat injection followed by one cryopreserved fat injection, six patients had one fresh fat injection followed by two cryopreserved fat injections, and five patients had two fresh fat injections and one or more cryopreserved fat injections. Results: In total, 281 sets of injection procedures were performed at various sites, of which 170 involved one fresh fat injection, 89 involved one fresh fat injection and one cryopreserved fat injection, and 11 involved one fresh fat injection and two cryopreserved fat injections. One patient experienced self-resolving inflammation as a complication after the second injection in the right cheek. No statistically significant differences were found between the fresh and cryopreserved fat injections. Conclusion: We suggest that cryopreserved fat is a useful and safe resource for multiple fat injections, with advantages including aseptic fat handling and the delicacy of the technique.

Effect of Gonadotropin Treatments on Ovarian Response, Ovulation and Embryo Production in Rabbits (토끼에서 선성자극호르몬 처리법에 따른 난소 반응, 배란 및 수정란 생산효율에 관한 연구)

  • 최창용;노규진;최상용
    • Journal of Embryo Transfer
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    • v.13 no.2
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    • pp.127-137
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    • 1998
  • This experiment was carried out to investigate the factors affecting superovulation in rabbits and to determine the effect of pFSH and PMSG on ovarian superovulatory responses and embryo production, and the effect of superovulation treatment with a single injection of pFSH dissolved in polyvinylpyrrolidone on the ovarian responses and the embryo quality. The results obtained were suonmerized as follows: Superovulatory response resulted in significantly (P<0.05) higher ovulation rates and more embryos in spring or autumn, compared with summer or winter. Repeated superovulatory treatments with PMSG leaded to a significantly(P<0.05) decreased number of total follicles and recovered ova. Superovulation with pFSH resulted in the higher number of ovulated follicles and recovered ova than with PMSG. A single subcutaneous injection of pFSH dissolved in 25% PVP resulted in the more ovulation points(33.2) and recovered embryos(30.2), which were comparable to the multiple injections of pFSH(44.8 vs 37.7).These results indicated that the treatment with a single injection of FSH dissolved in PVP was an efficient and simple alternative method to the conventional multiple FSH injections for superovulation in rabbits.

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Effects of Multiple Exposures to Pesticides on Plasma Cholinesterase Activity and p-nitrophenol Excretion in Rats (농약의 복합투여가 백서의 혈장 콜린에스테라제 활성도 및 요중 파라-니트로페놀 배설에 미치는 영향)

  • Cha, Bong-Suk;Park, Jung-Gyun;Park, Jong-Ku;Chang, Sei-Jin
    • Journal of Preventive Medicine and Public Health
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    • v.25 no.2 s.38
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    • pp.180-188
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    • 1992
  • The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with $LD_{50}/100(mg/kg)$ of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth Injection were delayed in comparision with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.

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Optoelectronics Properties of In0.27Ga0.73N/GaN Multi-Quantum-Well Structure (In0.27Ga0.73N/GaN 다중 양자우물 구조에 대한 광전기적 특성)

  • Park, Hun-Bo;Bae, In-Ho;Kim, Ki-Hong
    • Korean Journal of Materials Research
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    • v.17 no.9
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    • pp.489-492
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    • 2007
  • Temperature and injection current dependence of elctroluminescence(EL) spectral intensity of the $In_{0.27}Ga_{0.73}N/GaN$ multi-quantum-well(MQW) have been studied over a wide temperature and as a function of injection current level. EL peaks also show significant broadening into higher photon energy region with the increase of injection current. This is explained by the band-filling effect. When temperature is slightly increased to 300 from 15 K, the EL emission peak showed red-blue-red shift. It can be explained by the carrier localization by potential fluctuation of multiple quantum well and band-gap shrinkage as temperature increase. It is found that a temperature-dependent variation pattern of the EL efficiency under very low and high injection currents show a drastic difference. This unique EL efficiency variation pattern with temperature and current is explained field effects due to the driving forward bias in presence of internal(piezo and spontaneous polarization) fields.

In vivo kinetics and biodistribution of a HIV-1 DNA vaccine after administration in mice

  • Kim, Byong-Moon;Lee, Dong-Sop;Kim, Chae-Young;Son, Mi-Won;Sung, Young-Chul;Kim, Won-Bae
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.423.2-424
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    • 2002
  • The present study evaluates the pharmacokinetics and tissue distribution of GX-12, a multiple plasmid DNA vaccine for the treatment of HIV-1 infection. PCR analysis after i.v. injection in mice showed that plasmid DNA was rapidly degraded in blood with a half-life of 1.34 min and was no longer detectable at 90 min post-injection. Plasmid DNA concentration also rapidly declined at the injection site after i.m. injection. with less than 1 % of the initial concentration remaining at 90 min post-injection. (omitted)

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Superovulation in Korea Cattle with a Single Subcutaneous Injection of Folltropin-V Dissolved in Polyethyleneglycol (한우에 있어서 PEG에 용해시킨 Folltropin-V의 1회 피하주사에 의한 다배란 유기)

  • 임석기;우제석;전기준;장선식;강수원;윤상기;손동수
    • Journal of Embryo Transfer
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    • v.13 no.3
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    • pp.207-212
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    • 1998
  • This study was conducted to determined if single subcutaneous (s.c.) injection of Folltropin-V dissolved in polyethyleneglycol (PEG) can replace as the standard multiple intramuscular (i.m.) injection. The results suggest that the s.c. treatment produced more corpora lutea, embryos recovered and transferable embryos as compared to the i.m. treatment (p<0.05). This study indicates that a single s.c. injection of Folltropin-V dissolved in PEG was effective for superovulatory response and embryo yield in Korean cattle.

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A New All-optical Flip-flop Based on Absorption Nulls of an Injection-locked FP-LD

  • Lee, Hyuek Jae
    • Current Optics and Photonics
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    • v.4 no.5
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    • pp.405-410
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    • 2020
  • A new all-optical flip-flop (AOFF) method based on the absorption nulls of an injection-locked Fabry-Perot laser diode (FP-LD) in transverse magnetic (TM) mode is proposed and experimentally demonstrated. For the set and reset operations of the AOFF, injection locking and the destructive minus of beating in transverse electric (TE) mode are used. The absorption nulls on the TM mode are modulated according to the operations, and then non-inverted (Q) and inverted (${\bar{Q}}$) outputs can be obtained simultaneously. Thanks to the use of several absorption nulls, the proposed AOFF can achieve multiple outputs with extinction ratios of more than 15 dB. Even though the experiment is demonstrated at 100 Mbit/s, the results of previous experiments using the injection of a CW holding beam imply that the operation speed can increase to 10 Gbit/s.

Effects of Pilot Injection Method Following the Main Injection on Ignition Promotion and Exhaust Gas Reduction in a Diesel-Fueled HCCI Engine (디젤 예혼합압축착화엔진에서 주연료 분사 후 점화 연료 분사 방법을 통한 점화 촉진과 배기가스 개선 효과)

  • Kook, Sang-Hoon;Bae, Choong-Sik
    • 한국연소학회:학술대회논문집
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    • 2003.05a
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    • pp.27-32
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    • 2003
  • Diesel-Fueled HCCI(Homogeneous Charge Compression Ignition) Engine is an advanced combustion process explained as a premixed charge of diesel fuel and air is admitted into the cylinder and compression ignited. It has possibility to reduce NOx by spontaneous auto-ignition at multiple points that allows very lean combustion resulting in low combustion temperatures. Also PM could be reduced by the premixed combustion and no fuel-rich zones. But HCCI couldn't be realized because of the difficulties in vaporizing the diesel, control of combustion phase directly. To solve these problems, new fuel injection strategy, explained as the pilot fuel injection to promote ignition near TDC following the main fuel injection at the extremely advanced timing, is applied during the compression ratio is varied from 18.9:1 to 27.7:1 This is not a pilot fuel to promote the ignition but also the direct control method of the combustion phase. Experimental result shows the pilot fuel injection promote the ignition and the compression ignition of the HCCI engine is achieved as compression ratio becomes higher. Also there is an optimal pilot fuel injection timing for the HCCI combustion. NOx is reduced more than 90% compared to DI-Diesel case but PM and THC emission needs more investigation.

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New Core-Layer Soft Decoding Method for ATSC3.0 LDM-MIMO Broadcasting Systems (ATSC3.0 LDM-MIMO 방송 시스템을 위한 새로운 Core-Layer 연판정 기법)

  • Baek, Hyeonguk;Kim, Seunghyeon;Kim, Hojun;Jung, Taejin
    • Journal of Broadcast Engineering
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    • v.24 no.6
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    • pp.1072-1075
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    • 2019
  • In this letter, we propose a new soft decoding method for a Core-Layer(CL) signal in ATSC3.0 Layered-Division-Multiplexing Multiple-Inputs-Multiple-Outputs broadcasting systems. Unlike a conventional Gaussian-Approximation(GA) method, the proposed method decodes the CL signal by reducing a Enhanced-Layer signal simply to a QPSK signal, and thus exhibits greatly improved performance compared to the GA method especially for a lower CL injection-level.