• Journal of Biosystems Engineering
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• v.14 no.3
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• pp.207-214
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• 1989

In this study, impact force and angular displacement of the pendulum were measured by the load cell and potentiometer. Mechanical behavior of rough rice under impact loading was able to analyze precisely and efficiently, because measured data were accumulated and handled by the automatic data acquisition system making use of microcomputer system. Impact force and angular displacement were measured with a resolutiln of 1/1500 seconds in time. Mechanical behavior such as force and energy at rupture point of Japonica type and Indica type rough rice were measured with this system. After impact loading, the damage of rough rice was examined with the microphotograph and an allowable impact force was measured. The results obtained in this study are summarized as follows. 1. Machanical behavior of rough rice under impact loading was analyzed precisely and efficiently because measured data were accumulated and handled by this data acquisition system. 2. Rupture force and rupture energy of rough rice were appeared to be the lowest value in the range of 16 to 18 % moisture content, and rupture force and rupture energy of Japonica type were higher than those of Indica type in each level of moisture content. 3. From the result of the damage examined after the impact loading, allowable impact force was the lowest in the range of 16 to 18 % moisture content, and the value of the allowable impact force of Japonica type was higher than that of Indica type in each level of moisture content.

• Journal of Auto-vehicle Safety Association
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• v.4 no.1
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• pp.5-11
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• 2012

This paper discusses the evaluation of the safety impact of the Adaptive Cruise Control (ACC) system in Korea. To evaluate the safety impact, this paper suggests an analysis method by using the test scenario and field operational test data. The test scenario is composed to represent the main component factor of the ACC system and ACC related accident situation such as rear-end collision, lane-change, and road-curvature, etc. Also, from the field operation test data, the system's potential to increase the safety can be measured ideally. Besides, field operational testdata was used to revise the expected safety impact value as Korean road conditions. By using the proposed evaluation method, enhanced safety impact of the ACC system can be estimated scientifically.

• The Journal of the Acoustical Society of Korea
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• v.15 no.1E
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• pp.5-19
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• 1996

This paper proposes a loose part monitoring system (LPMS) design with a signal processing method based on fuzzy logic. Considering fuzzy characteristics of metallic impact waveform due to not only interferences from various types of noises in an operating nuclear power plant but also complex wave propagation paths within a monitored mechanical structure, the proposed LPMS design incorporates the comprehensive relation among impact signal features in the fuzzy rule bases for the purposes of alarm discrimination and impact diagnosis improvement. The impact signal features for the fuzzy rule bases include the rising time, the falling time, and the peak voltage values of the impact signal envelopes. Fuzzy inference results based on the fuzzy membership values of these impact signal features determine the confidence level data for each signal feature. The total integrated confidence level data is used for alarm discrimination and impact diagnosis purposes. Through the perpormance test of the proposed LPMS with mock-up structures and instrumentation facility, test results show that the system is effective in diagnosis of the loose part impact event(i.e., the evaluation of possible impacted area and degree of impact magnitude) as well as in suppressing false alarm generation.

• Land and Housing Review
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• v.5 no.2
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• pp.81-89
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• 2014

This paper presents various attempts to secure the floor impact sound insulation performance on the dry floor system of steel framed modular house that lately attracted domestic attention. Test results show that in the condition of using dry floor system of D31(D32), the light-weight impact noise performance records the top level in the floor impact sound insulation performance grading system. the heavy-weight floor impact noise performance meets the minimum sound level limit in the floor impact sound insulation performance grading system that enacted regulation on housing construction standards.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.7 s.112
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• pp.754-761
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• 2006

This paper presents the dynamic characteristics of MR impact damper for vehicle collision system. Various types of mechanism have been proposed to reduce force transmitted to the vehicle chassis and finally to protect occupants from injury. In the case of head-on collision, the bumper makes main role of isolation material for collision attenuation. In this study, the proposed bumper system consists of MR impact damper and structures. The MR impact damper utilizes MR fluid which has reversible properties with applied magnetic field. The MR fluid operates under flow mode. The bellows is used for generation of fluid flow. A mathematical model of the MR impact damper is derived incorporating with Bingham model of the MR fluid. Field dependent damping force is investigated with time and frequency domain. The MR impact damper is then incorporated with vehicle crash system. The governing equation of motion of vehicle model is formulated considering occupant model. Dynamic characteristics of vehicle collision system investigated with computer simulation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.147-152
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• 2006

This paper presents the dynamic characteristics of MR impact damper for vehicle collision system. Various types of mechanism have been proposed for reduce transmitted force to vehicle chassis and finally protect occupants from injury. In the case of frontal collision, the bumper make main role of isolation material for collision attenuation. In this study, proposed bumper system composed of MR impact damper and structures. The MR impact damper is to adopted MR fluid which has reversible properties with applied magnetic field. MR fluid operates under flow mode with Bingham flow and bellows is used for generation of fluid flow. Mathematical model of MR impact damper incorporated with MR fluid is established. Field dependent damping force is investigated with time and frequency domain. The MR impact damper is then incorporated with vehicle crash system. The governing equation of motion of vehicle model is formulated considering occupant model. Dynamic characteristics of vehicle collision system investigated with computer simulation.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.127-133
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• 2013

PURPOSES : The impact performance of flexible barrier system such as structural response, vehicular motion and occupant safety vary depending on the impact point. Thus, to properly evaluate the performance of a flexible barrier system, impact should be made to a point which will lead to the worst possible results. This point is called the Critical Impact Point (CIP). This paper presents the way to determine the CIP for a SB2 class flexible barrier system which is consisted of Thrie-Beam rail and circular hollow tube post of 2m span. METHODS: Barrier VII simulations were made for impact points; Case 1 at a post, Case 2 at 1/3 span downstream from a post, Case 3 at middle of the span, Case 4 at 2/3 span downstream from a post. For the structural performance (deflections), impact simulation of 8000kg-65km/h-15degree was used, and for vehicle motion and occupant safety, simulation of 1300kg-80km/h-20degree impact was made and analysed. RESULTS: Case 1 gave the largest dynamic deflection of 75.72cm and also gave the largest snag value of 44.3cm. Occupant safety and exit angle of the vehicle after the impact were not sensitive to the impact point and were all below the allowable limit. CONCLUSIONS : For the SB2 class flexible barrier system's CIP can be regarded as a post which is sufficiently away from the end of Length of Need in order to avoid the end-effect of the barrier system. It can be more economic in the long run because the normal concrete pavement material is likely to cost more due to higher probability of maintenance and repair and higher social cost due to traffic accident, etc.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.425-428
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• 2000

In this paper the impact force which occurs on each tooth of jaw-bones while masticating is calculated through the rigid body dynamic analysis. This analysis is done by ADAMS. The impact force calculated in this paper is required for the structural stress analysis of implant system which is needed for the implant system design. The analysis results show that the impact time decreases as the impact force increases, the largest impact force occurs on the front tooth and the impact force is almost normal to the tooth surface together with slight tangential force.

• Journal of Environmental Impact Assessment
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• v.12 no.5
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• pp.359-367
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• 2003

The total pollution load management system of watershed has been implemented upon Special Law pertaining to the Han River Watershed Water Quality Improvement and Residents Support, Special Law pertaining to the Nakdong River Watershed Water Management and Residents Support, Special Law pertaining to the Youngsan River Watershed Water Management and Residents Support, and Special Law pertaining to the Seomjin River Watershed Water Management and Residents Support in Korea since 2002. But many other similar systems with total pollution load management system of watershed are being operated separately or independently, even though its purpose is nearly same with those of the total maximum pollutants load management in Law on Water Quality Environmental Protection, environmental impact assessment(EIA) in Law of Impact Assessment on Environment, Transportation and Disaster and Pre-environmental assessment of Environmental Policy Act. Therefore the contents of total pollution load management system of watershed and many other related systems could be overlapped and at some times have inconsistency among them. This study suggests first the integrated operation of total pollution load management system of watershed, EIA, pre-environmental assessment, urban planning, and sewage planning and secondly EIA system development by integration of EIA and pre-environmental assessment and strategic environmental assessment(SEA).

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.255-264
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• 2013

This paper diagnosed the assessment problems and development types of the simple statement of the Sea Area Utilization Consultation System. and suggested the key assessment items for system improvement. The major types of Public Water occupation and use, and distribution characteristic of regional and coastal were analyzed by evaluate 529 review items during 2010-2012. The artificial structure installation including harbor and fishing port facilities in the South and West coast, and seawater supply and drainage for land-based aquaculture and power plant were dominated. The checklists considering each types of occupation and use in Public Water were suggested. In addition, policy proposals for system improvement were suggested.