• Design & Manufacturing
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• 제15권1호
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• pp.48-56
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• 2021

The quality of products produced by injection molding process is greatly influenced by the process variables set on the injection molding machine during manufacturing. It is very difficult to predict the quality of injection molded product considering the stochastic nature of manufacturing process, because the process variables complexly affect the quality of the injection molded product. In the present study we predicted the quality of injection molded product using Artificial Neural Network (ANN) method specifically from Multiple Input Single Output (MISO) and Multiple Input Multiple Output (MIMO) perspectives. In order to train the ANN model a systematic plan was prepared based on a combination of orthogonal sampling and random sampling methods to represent various and robust patterns with small number of experiments. According to the plan the injection molding experiments were conducted to generate data that was separated into training, validation and test data groups to optimize the parameters of the ANN model and evaluate predicting performance of 4 structures (MISO1-2, MIMO1-2). Based on the predicting performance test, it was confirmed that as the number of output variables were decreased, the predicting performance was improved. The results indicated that it is effective to use single output model when we need to predict the quality of injection molded product with high accuracy.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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• pp.175-182
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• 2002

The cement injection technology on the purpose of ground reinforcement and cut-off has been used in construction sites until now. However, recently it is applied to prevent leakage of underground structure. In this study, applicability of the back side waterproof grouting method was verified through performing field model tests and reviewing case histories. From the results of this study, injection shape of the back side waterproof grouting method was appeared to be root type, and waterproof effect by injection of cement grout material was excellent because grout material infiltrated into boundary between wall of structure and back side ground to be waterproof layer. Components influencing infiltration of injection material are type of soil and degree of compaction. For effective injection, injection pressure has to vary gradually from high pressure to low pessure and small quantity of injection material has to be injected for long times. Also, spacing of injection hole must be designed considering condition of back side ground, injection area, W/C ratio, the number of injection and injection pattern properly.

• 대한기계학회논문집B
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• 제30권1호
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• pp.48-56
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• 2006

We investigated gas residence time and mixing characteristics due to various swirl numbers generated by normal injection of secondary air to a lab-scale cylinderical combustor. The residence time was estimated by measuring the temporal pressure difference which was caused by deposition of test particles on a filter media after the injection by a syringe. The mixing characteristics were evaluated by standard deviation value of test gas concentration at different measuring points. The test gas concentration was detected by a gas analyzer. The swirl number of $20{\sim}30$ for ${\theta}=5^{\circ}$ caused long residence time enough to improve mixing characteristics. Numerical calculations were also carried out to understand physical meanings of the experimental results.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 추계학술대회 논문집
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• pp.69-72
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• 2008

This paper presents the transient and conventional grounding impedance behaviors of large grid grounding system associated with the injection point of impulse current The measurement methods consider two possible errors in the grounding-system impedances: (1) ground mutual resistance due to current flow through ground from the ground electrode to be measured to the current auxiliary, (2) ac mutual coupling between the current test lead and the potential test lead The test circuit was set to reduce the error factors. The transient grounding impedance depends on the rise time and injection point of impulse current It is effective that grounding conductor is connected to the center of the large grid grounding system.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.611-618
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• 2002

In this study the CGS as an injection method by low slump mortar was performed the pilot test to confirm the applicability of this method and the effectiveness of settlement restraint. From the results, there has been concluded the construction control standard such as an institutional diameter, space, depth, injection materials, Infection pressure etc. Also, there has been estimated the ground improvement effectiveness which has resulted from the field investigation and consolidation test etc. From the results, in the adjacent ground the CGS, generally, has been confirmed to in-crease ground strength to improve the consolidation characteristic obtained from the field investigation and consolidation test. Especially, the CGS which performed the larger stiffness to the ground has been concluded that the settlement restraint to the ground complicates the ground effect which Increases the bearing capacity and stress assignment. So, the CGS can be considered as an effective method to increase the bearing capacity as well as the settlement restraint of soft ground.

• 자원환경지질
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• 제43권4호
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• pp.371-379
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• 2010

연안지역 염수와 담수가 혼재하는 전이대에서 해수침투 피해개선을 목적으로 균열암반을 통한 담수주입시험을 수행하고 그 효과를 모니터링하였다. 담수주입은 절대적으로 그 지역의 지질학적, 수리학적 특성에 따라 좌우되며, 특히 파쇄대나 투수성 미고결 지층 등의 특성 파악이 중요하다. 연구 지역의 염담수 분포특성을 고려하여 두 개의 주요 연안 대수층인 충적층과 균열암반 구간을 통한 담수주입이 가능하도록 시추공을 설계 및 굴착하였으며, 균열암반 대수층 내 담수주입을 위하여 현장에서의 시험 준비, 이동, 조립 및 장비의 유지보수가 간단하도록 착탈식인 모듈화되어 있는 주입시스템을 제작하여 적용하였다. 시추공영상화검층을 통해 전체적인 균열의 특성을 파악하였고, 이를 바탕으로 주입공 및 관측공 간 투수성 파쇄대의 확인을 위한 구간별 담수주입 및 모니터링을 실시하여 담수주입 구간을 선정하였다. 담수주입시험 결과, 관측공의 일정 심도에서 담수가 유입되어 시간이 경과함에 따라 상부 구간의 전기전도도도 점진적으로 감소함을 보였으며, 담수주입 중단 및 패커를 해지한 후에도 유입된 심도에서 점진적으로 전기전도도값이 증가하기는 하지만 그 증가폭이 전체적으로 낮아 담수주입의 효과가 있음을 확인하였다. 또한 장기적으로 전기전도도값을 모니터링함으로써 담수주입의 효과가 수개월 후에도 지속됨을 확인하였으며, 이는 담수주입에 의해 일정 정도의 해수침투 피해에 대한 개선효과를 기대할 수 있음을 시사한다.

• 대한전기학회논문지:전력기술부문A
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• 제50권6호
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• pp.287-292
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• 2001

This paper deals with the configuration, operating principles, systematic calculation method of parameter and optimization method of test circuit for parallel current injection method, series voltage injection method and hybrid synthetic test method as the method for performance test of circuit breaker with extra high interrupting capacity. The test method depicted above is applied to short-circuit making and breaking test (operating sequence :Os CdOs, Od-CdOs) and out-of-phase tests(operating sequence :Os, CdOs) for performance test of the newly-developed 420kV, 50kA and 800kV 50kV puffer-type gas circuit-breaker according to IEC 60056 and IEC 60427. The testing results, evaluation of equivalence for test and analyzed results are also presented in this paper.

• 대한수의학회지
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• 제32권4호
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• pp.677-681
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• 1992

This experiment was carried out to establish a proper method of indocyanine green(ICG) excrection test for a applicable liver function test in three Korean native cattle average weighing about 450kg and dairy cattle parity of 3~5. The results obtained the half life($T^1/_2$), fractional clearance rate(KICG), retention rate and plasma enzyme activities before or after injection of ICG were as follows. 1. The maximum absorbance of ICG in plasma was at 805nm. 2. Average half life and fractional clearance rate following the injection of ICG 0.25mg/kg body weight were $5.53{\pm}1.27$ minute and $0.131{\pm}0.031$/minute in Korean native cattle, $4.55{\pm}0.68$ minute and $0.156{\pm}0.031$/minute in dairy cattle, respectively. The ICG removal rate was exponentially liner for the first 15 minutes after injection both of Korean native cattle and dairy cattle. 3. Average plasma retention rate when 10, 15, 30 minutes after injection was $35.7{\pm}13.9$, $23.2{\pm}7.1$, $10.8{\pm}3.5%$ in Korean native cattle, $26.8{\pm}3.3$, $14.2{\pm}1.2$, $5.5{\pm}2.2%$ in dairy cattle, respectively. 4. Plasma enzyme activities(AST, ALT, r-GTP) were no variation among the before, during and after injection of ICG. From these results, ICG excretion test to cattle is applicable to evaluation of liver funtion in both clinical and research, and adopted the 15 minutes plasma sample as the sample taken at the ideal time for comparative purposes.

• 한국기계가공학회지
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• 제13권4호
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• pp.69-74
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• 2014

A waste gate valve (WGV) assembly for a gasoline turbocharger is typically manufactured by means of precision casting. In this study, however, it was newly manufactured in a more innovative way, metal injection molding (MIM) using Inconel 713C alloy, and its performance was tested in a 1.6L direct injection gasoline engine by a thermal shock durability test that lasted 300 hours, after which the results were compared to those of a precision-cast WGV assembly with regard to the engine intake boost pressure, turbine wheel speed, and transient intake pressure. It was found that the two WGV assemblies showed similar performance levels throughout the durability test.

• 한국분무공학회지
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• 제10권1호
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• pp.24-34
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• 2005

Injection technology is one of the important technologies in a diesel engine. Many studies have done on the injection system. In this study, the fuel chamber geometry, the orifice ratio and the needle lift of the injection valve for a marine diesel engine are varied, and simulated. The result shows that the nozzle hole size has influence on the rail pressure and injection duration sensitively. The decrease of the static pressure at the nozzle hole entrance and the increase of the dynamic pressure on the outlet surface are occurred with the increase of the nozzle hole diameter. The highest dynamic pressure of the outlet was occurred at the needle lift of 0.4mm and the nozzle hole diameter of 0.328mm in this test nozzle.