• 한국환경과학회지
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• 제7권6호
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• pp.793-801
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• 1998

In this study, the Dilution Method is used to measure river discharge through the hydraulic model test. the dilution method is divided into Constant-Rate-Infection Method and Slug-Injection Method in the river discharge measurement techniques. When the dilution method is applied in the hydraulic model flume, it is analyzed that the estimated error of constant-rate-injection method is less than that of the slug-in-jection method, and the result shows that floodflow analysis is more efficient than lowflow analysis as compared observed discharge with calculated discharge. The result of statistical error analysis shows that the constant-rate-injection method is appropriate technique for the measurement of the river discharge. Therefore, the dilution method among the river discharge measurement techniques can be applied for the river basin which can't be measured with current meter or unsteady-flow regime in the urban-small drainage or hydraulic structure equipment area and can be obtained more exact results than any other discharge measurement techniques.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.240-243
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• 2008

회전식 연료 노즐의 분무특성을 알기 위해서 고속회전 시험장치를 이용하여 실험적 연구를 수행하였다. 시험장치는 연료공급장치, 고속 회전장치 그리고 아크릴 케이스로 구성되어있다. Injection orifice의 직경 및 개수를 변화시켜가며 분무실험을 수행하였다. 액적의 크기 및 속도는 PDPA(Phase Doppler Particle Analyzer)시스템을 이용하여 측정하였다. 실험결과로부터 Injection orifice의 직경 및 개수변화에 따른 회전식 노즐의 분무특성을 이해 할 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.347-354
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• 2002

In this paper, when structures are constructed in the soft ground with poor bearing capacity at Incheon International Airport(railroad area), as for the grouting columns built In soft ground by high pressure jet grouting with Triple tube rod(super injection grouting), the effects on reinforcement and bearing capacity of ground are investigated. A unconfined compressive strength tests has been performed on the specimens sampled from the grouting columns and a mass plate bearing test has been performed on a grouting column. The test results show that super injection grouting has a sufficient effect on composite ground improved of foundation ground and reatraint of settlement of structure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.41-42
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• 2017

In this study, an investigation was made to study the chemical resistance performance of epoxy resin injection type leakage repair material used in the Korean construction market in accordance to the test method outlined in "ISO TS 16774, Part 2; Test Method for Chemical Resistance." This is a new standard document used for quality control method of injection type repair material used for leakage cracking of underground concrete structures. The results of this study can be expected to be utilized as reference data that can be used for quality improvement of the maintenance methods for future construction.

• Toxicological Research
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• 제12권1호
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• pp.101-111
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• 1996

The local irritation studies of DA-3285, recombinant human erytropoietin(rHu-EPO), were carried out in rabbits after the following treatment; single application into the conjunctival sac of the eye, single subcutaneous injection, 7-day repeated subcutaneous injection and 8-day repeated infusion into the ear vein. Also, the local irritancy of DA-3285 leaked around vein was studied in mice by single perivascular injection. The results obtained were as follows. In the result of ocular irritation test, DA-3285 could be considered as a non-irritating material. In single and 7-day repeated subcutaneous irritation test, the irritancy of DA-3285 was not so much different from that of saline. The vascular irritancy of DA3285 by 8-day repeated infusion was negligible and similar to that of saline. And the irritancy of DA3285 by perivascular injection was comparable to that of saline. These results indicate that DA-3285 has no irritating activity when injected through subcutaneous or intravenous route for clinical practice as 3.5% solution.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.1-5
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• 2008

An experimental study was performed to develop the rotational fuel injection system of the micro turbojet engine. In this system, fuel is sprayed by centrifugal forces of engine shaft. The test rig was designed and manufactured to get droplet information on combustion space. This experimental apparatus consist of a high speed rotational device(Air-Spindle), fuel feeder, rotational fuel injector and acrylic case. To understand spray characteristics, spray droplet size, velocity and distribution were measured by PDPA (Phase Doppler Particle Analyzer) and spray was visualized by using Nd-Yag laser-based flash photography. From the test results, the length of liquid column from injection orifice is controlled by the rotational speeds and Sauter Mean Diameter(SMD) is decreased with rotational speed. Also, Sauter Mean Diameter is increased as increasing mass flow rate at same rotational speeds.

• Corrosion Science and Technology
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• 제20권3호
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• pp.143-151
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• 2021

In this study, optimal shot peening process conditions were investigated for improving the cavitation erosion resistance of gray cast iron under a marine environment. Shot peening was performed with variables of injection pressure and injection time. The durability was then evaluated through cavitation erosion test which was conducted according to the modified ASTM G-32 standard. The tendency of cavitation erosion damage according to shot peening process condition was investigated through weight loss rate, surface and cross-sectional analysis of the specimen before and after the test. As a result, the shot peening process condition that could minimize cavitation erosion was when the injection pressure was the lowest and when the injection time was the shortest. This was because the flake graphite exposed on the gray cast iron surface could be easily removed under such condition. Therefore, the notch effect can be prevented by surface modification. In addition, the cavitation erosion damage mechanism of gray cast iron was discussed in detail.

• The Korean Journal of Physiology and Pharmacology
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• 제9권1호
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• pp.23-27
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• 2005

The present study was performed to investigate the effects of intra-articular injection of interleukin-1${\beta}$ (IL-1${\beta}$) on the formalin-induced temporomandibular joint (TMJ) pain. Under anesthesia, a 30-gauge needle was introduced into the right TMJ region for injection of formalin. Microinjection of 50 ${\mu}l$ of 5% formalin significantly produced noxious scratching behavioral response, and the scratching behavior lasted for 40 min. Although the responses produced by formalin injection were divided into two phases, the response of 1st phase did not significantly differ from the scratching behavior response in the saline-treated group. We examined the effects of intra-articular injection of IL-1${\beta}$ on the number of noxious behavioral responses produced by 50${\mu}l$ of 5% formalin injection. Intra-articular injection of 100 pg and 1 ng of IL-1${\beta}$ significantly increased the number of behavioral responses of the 2nd phase, while 10 pg of IL-1${\beta}$ did not change the formalin-induced behavioral responses. To investigate whether IL-1 receptor was involved in the intra-articular administration of IL-1${\beta}$-induced hyperalgesic response, IL-1 receptor antagonist (IL- ra, 50 ng) was administrated together with IL-1${\beta}$ injection. IL-1${\beta}$ receptor antagonist blocked IL-1${\beta}$- induced hyperalgesic response in the TMJ formalin test. These results suggest that intra-articular injection of IL-1${\beta}$ facilitated the transmission of nociceptive information in the TMJ area.

• 동서간호학연구지
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• 제11권2호
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• pp.137-145
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• 2005

Purpose: This study has been attempted as one of the Quality Improvement activities in order to provide with intravenous injection control and to confirm the evaluation from the patients and their guardians, and also from nurses themselves. Method: The subject of this intravenous injection control was a control group of 239 patients and 176 nurses, a comparison group of 128 patients and 146 nurses. The tool consisted of hospitality (towards patients), explanation, and infection prevention activities. The collected data were analysed using SPSS Windows 11.0 program for percentage, $X^2$-test and t-test. Result: 1) The nurses who were instructed in standardised intravenous injection control received more satisfactory evaluation from the patients(t=-2.89, p=.004) than the nurses who were not. However, in the subdivisions, the explanation field was the only one to receive a more satisfactory evaluation(t=-1.14, p=.255). 2) The nurses who were instructed in standardised intravenous injection control showed higher performances in intravenous injection control (t=-4.21, p=.000) than the nurses who were not. In the subdivisions, hospitality, explanation, and infection prevention activities all showed effectiveness ($t=-2.35{\sim}3.90$, $p=.020{\sim}.000$). Conclusion: From the results stated above, it can be concluded that standardised intravenous injection control instruction for nurses brought out better evaluation, i.e. satisfaction, from the patients and their guardians, and the nurses who received the instruction showed better performances in intravenous injection control.

• 한국음향학회지
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• 제40권1호
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• pp.38-45
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• 2021

본 연구는 함정 추진기에 적용되고 있는 공기분사에 의한 수중방사소음 저감기술에 대한 연구기반을 마련하고자 캐비테이션 터널에서 단순화된 모형을 이용하여 공기분사에 의한 캐비테이션과 소음의 변화에 대하여 연구하였다. 추진기 날개와 유사한 특성을 나타내는 3차원 타원형 수중익에 공기분사 위치와 분사량을 조절할 수 있는 공기분사시스템을 제작하였으며 캐비테이션 터널 시험조건을 조절하여 수중익에 다양한 형태의 캐비테이션을 모사하고 공기분사에 따른 캐비테이션과 소음특성의 변화를 실험적으로 분석하였다. 공기분사 위치 및 분사량에 따라 캐비테이션 및 소음특성이 달라짐을 확인하였다. 이는 추진기에 공기분사 기술을 적용하기 위해서는 캐비테이션의 발생위치, 거동에 따른 공기 분사위치 및 분사량의 최적화가 필요함을 의미한다.