• 한국분무공학회지
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• 제13권2호
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• pp.85-90
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• 2008

This paper presents the performance and emissions characteristics of a small spark-ignited gasoline engine. The engine used in this paper is a single cylinder, diaphragm carburetor, two-stroke, air-cooled 26cc SI engine for brush cutter. For the performance of the engine, RPM, torque, and fuel consumption were measured and HC, CO, and NOx measured for the emissions according to the change of the dynamometer load at wide open throttle (WOT) position. The results showed that the excess air ratio decreased and torque increased with increasing loads, the torque and brake specific fuel consumption were the optimum driving condition at the 7000 rpm, HC and CO emissions increased with increasing loads and with an decrease in excess air ratio over 7000 rpm.

• 한국산학기술학회논문지
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• 제17권4호
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• pp.100-105
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• 2016

3D 프린터의 증가에 따라 대량 생산이 아닌 소량 제품의 빠른 개발 시간을 고려하여 3D 스캐너의 활용도 점차 증가하고 있다. 소량 생산 개발 트렌드뿐만 아니라 최근 자동차 및 전자부품의 제조업에 있어서도 정밀 부품의 개발 및 검사, 측정 등의 품질 문제가 중요한 이슈로 떠오르고 있다. 최근 3D 스캐너 장비 효율성 및 인식기술은 지속적으로 향상되었지만, 이에 반해, 이를 준비하는 스프레이 작업은 시간이 많이 걸리고 환경문제가 유발되기 때문에 제조업 제품 개발자들은 자동스프레이 도포 시스템 개발에 대해 지속적으로 요구해 왔다. 본 연구를 통해서 3D 스캔 준비 작업으로 필요한 스프레이 자동 도포 장비를 개발하였으며, 스프레이 도포 시 균일하게 미세 분말이 도포 될 수 있도록 파라미터 세팅에 대해 실험적으로 연구하였다. 결과적으로 빠르고 쉬운 자동 스프레이 도포 장비가 개발 되었고, 이를 활용해서 3D 측정을 위한 준비 시간이 기존 대비 1/10수준으로 단축되었다. 또한 다양한 조건에 대한 비교를 통해 최적의 도포 조건을 실험적으로 제시하였다.

• 한국분무공학회지
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• 제14권1호
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• pp.28-33
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• 2009

This paper presents the performance and emissions characteristics of a small spark-ignited 2-stroke gasoline and LPG engine. The engine used in this paper is a single cylinder, two-stroke, air-cooled SI engine for brush cutter. We measured the rpm, torque, fuel consumption and HC, CO, NOx emissions in associated with the dynamometer load at WOT. The results showed that as engine revolution speed decreased, the excess air ratio of gasoline engine kept going about 0.9 and that of LPG engine increased 0.83 to 1.05. Torque and power of gasoline engine was higher than LPG engine. In exhaust emissions, HC emissions of gasoline engine was lower than LPG engine. In low speed area, CO emissions of LPG engine was lower than gasoline engine. Both gasoline engine and LPG engine emitted little NOx emissions.

• 한국분무공학회지
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• 제14권1호
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• pp.34-38
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• 2009

This paper presents the pulsation of carburetor inlet and outlet pressure of a small SI gasoline engine. The engine used in this paper is a 23cc, single cylinder, diaphragm carburetor, two-stroke, air-cooled for brush cutter. The rpm and pressure wave pulsation at the inlet and the outlet of carburetor were measured and analysed for the understand of the internal air flow into the barrel on the diaphragm carburetor. These data should be used for the development of the duel fuel injection system for gasoline and LPG. The results showed that the carburetor inlet pressure variations were very steady, but the pressure variations at carburetor outlet were very sensitive to the pressure variation into the crank case and were to similar independently to the engine speed on partial opened throttle conditions. According to increasing engine speed, the pressure waves started to come out and be developed after closing the intake port of the engine at carburetor outlet. Reverse flow occurred on the WOT (wide open throttle) condition.

• 한국산업보건학회지
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• 제26권2호
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• pp.139-146
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• 2016

Objectives: This study aimed to confirm the optimal processing conditions of the asbestos stabilizer by considering various actual environments at the time of stabilization treatment of the ceiling materials containing asbestos with asbestos stabilizer. Methods: The anti-scattering performances of the asbestos stabilizer were confirmed by considering the method and quantity of the asbestos stabilizer treated, comparing the loss weight by measuring the weight of ceiling materials prior to and after having treated 30, 50, 100, 200, and 400 of stabilizer using the brush and spray. The effects of backside dust and steel frame structure on the performances of the stabilizer was also confirmed by comparing samples with and without the dust on the rear surface removed by wiping the ceiling material specimens and the blinding treatment simulated by using tape. Results: The asbestos stabilization treatment using the brush method in comparison with the use of a spray has reduced stabilizer loss, resulting in better anti-scattering performance. In addition, the stabilizer loss is increased with increasing treatment quantity; as a result, treating a larger quantity of stabilizer does not improve the performance. For the conditions related to ceiling materials, the anti-scattering performance is enhanced by removing the backside dust and spreading the stabilizer evenly on the masking portion by steel frame structures. Conclusions: Based on these results, it is determined that the appropriate choice of the tool used for the treatment of the asbestos stabilizer and the appropriate quantity of asbestos stabilizer were needed at the time of actual stabilization processing of the ceiling materials containing asbestos. Moreover, this study confirmed that preliminary processing and verification of the structure at which the ceiling materials are installed can enhance the effectiveness of prevention of the scattering of asbestos into the air.

• Journal of the Korean Wood Science and Technology
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• 제36권6호
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• pp.113-120
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• 2008

본 연구는 포름알데히드와 같은 유해화학물질을 저감하고, 인체에 무해한 친환경 건축마감재를 개발하기 위하여 대나무숯분말, 편백추출수 및 바인더를 원료로 이용하여 실내 건축마감재용 액상코팅제를 제조하였다. 편백추출수의 함유량에 따른 액상코팅제의 유해화학물질에 대한 탈취율, 원적외선방사율, 음이온방출량, 항균성 및 실제 소요량을 조사하였다. 액상코팅제의 포름알데히드 탈취율은 60.0~98.6%, 암모니아 탈취율은 76.7~86.2%였다. 편백추출수의 혼합량이 증가함에 따라 탈취율도 증가하는 경향을 보였다. 액상코팅제의 원적외선방사율은 91.7%, 음이온 방출량은 77개/cc 였으며, 세균감소율은 99.4%로 항균력이 우수하였으나, 편백추출수의 혼합량 증가에 따른 이들 값에는 차이가 인정되지 않았다. 액상코팅제의 소요량은 스프레이건을 사용할 경우 $0.66kg/m^2$, 붓칠의 경우 $0.94kg/m^2$로 스프레이건을 이용할 경우가 더 효율적이었다.