간행물
한국기계기술학회지 KCI 등재 Journal of the Korean Society of Mechanical Technology 韓國機械技術學會誌
- 발행기관 한국기계기술학회
- 자료유형 학술지
- 간기 격월간
- ISSN 1229-604X (Print)2092-0385 (Online)
- 수록기간 1999 ~ 2024
- 주제분류 공학 > 기계공학 공학 분류의 다른 간행물
- 십진분류KDC 550DDC 620
권호리스트/논문검색
제12권 제1호 (2010년 3월) 13건
<학술연구>
1.
2010.03
구독 인증기관 무료, 개인회원 유료
A hierarchical computational method has been developed and used with finite element method based on dislocation density multiple-slip crystalline formulation to predict how nanoindentation affects behavior in face-centered cubic crystalline aggregates. Using displacement profiles which were obtained from molecular dynamics(MD) nanoindentation simulation, scaling relations based on indentation depths, grain-sizes, and grain aggregate distributions were obtained. These relations then applied to coarsen grains in micros- tructurally based FE formulation which accounts for dislocation density evolution, crystalline structures. This computational regime was validated with a several experimental results related to single gold crystals. This hierarchical model provides a tool to link nanosacle level with a microstructurally based FEM formulation that can be to ascertain inelastic effects such as dislocation density evolution. With the above certainty temperature distribution during the nanoindentation simulation also was investigated along with the different indentation depth.
4,000원
2.
2010.03
구독 인증기관 무료, 개인회원 유료
Over the past years, many research works have been carried out to investigate the factors which govern the performance of diesel engine. The air pollutant emission from the diesel engine is still a significant environmental concern in many countries. In the present study, new system of smoke reduction of diesel engine is proposed. This new system is using vacuum equipment and STS filter for capture smoke. To confirm new system experiments were performed at engine dynamometer. As a result of this experiment, the smoke reduction ratio of this system was identified high reduction ratio than PDPF. But the power of this system application was measured 10% decrease than base engine performance. There were improvement effects of using STS filter than ceramic filter.
4,000원
3.
2010.03
구독 인증기관 무료, 개인회원 유료
Domestic SUV were evaluated for rating the ability of seat and head restraints to prevent neck injury in low speed rear-end crashes. The dynamic test criteria are divided into two groups-seat design parameters(Initial evaluation) and test dummy response parameters(Dynamic evaluation). Head restraint designs with initial geometric ratings of “acceptable" or “good" will be tested in a simulated 16 km/h rear impact to assess whether they provide effective dynamic support for the torso, neck and head. In the measurement and rating of static head restraint geometry, the initial static geometric rating of the domestic SUV cars were “good" except the A-car. In the final rating of the seat and head restraints, W-Car was “good", the other cars were “poor". The performance of dynamic test for the most part of the domestic SUV cars were “poor" and it is necessary to improve.
4,000원
4.
2010.03
구독 인증기관 무료, 개인회원 유료
The Effects of cooled and hot EGR(exhaust gas recirculation) on the characteristics of smoke and NOx emission have been investigated using a single cylinder, water-cooled, four cycle, DI diesel engine at several loads and speeds. In this study, a manually controlled EGR system was installed on a agricultural diesel engine which was operated at various operating system. And, the effects of hot EGR and cooled EGR on smoke and NOx emission were compared. The results showed that cooled EGR method was more effective than hot EGR method on smoke and NOx emission.
4,000원
5.
2010.03
구독 인증기관 무료, 개인회원 유료
This study was experimentally analyzed to search the swirl characteristics of helical intake port for the performance improvement in direct injection diesel engine. The intake port flow is important factor which has influence on the engine performance because the properties in the injected fuel depend on the combustion characteristics. In order to analyze the characteristics of swirl in the helical intake port of cylinder head, flow coefficient and swirl ratio were measured by an impulse swirl torque meter at position of 1.75 cylinder diameter for different valve lifts at the steady flow condition with intake port of the in-line and V type engine. Each intake ports were established swirl ratio 1.70, 2.13, 2.25, 2.38 and 2.43 by hand working. The results of steady flow test showed that flow coefficient and swirl intensity increased as valve lift increased, while the increase of swirl ratio according to the change of intake port geometry decreased mean flow coefficient and increased Gulf factor.
4,000원
6.
2010.03
구독 인증기관 무료, 개인회원 유료
The small catamaran leisure boat which is 4.1m length, 1.9m breadth and 0.7 ton displacement was designed. To decide optimum breadth, four sets of distances between hulls were considered. CFD analysis using FLUENT was performed to examine flow patterns, pressure distribution and wave height between two hulls. Model test at CWC in INHA Technical College was also carried out to get the resistance for final hull form at design speed 5 knots. The feature of flow pattern among four different distances between hulls were compared and discussed. The optimum breadth of design vessel was decided depending on the CFD results and comments of expertise that has experience on board the small demihull. The design procedure to choose optimum breadth, especially small change of the hull distance, using CFD was described in this paper
4,000원
7.
2010.03
구독 인증기관 무료, 개인회원 유료
This study investigated tensile deformation of the stress aging heat-treated SM45C steel which are aging temperature at 250℃ and 300℃; aging time at 1 hour and, 3 hours; applied load at 300N and 400N by using an acoustic emission techniques (AEs). A signal processing technology is applied to evaluate an AE source characterization of different AE measurement systems DiSP & PCI-2. In this study, most suitable aging condition appeared at 250℃, 3 hours and 300N. But in cases of 250℃, 3 hours, 400N and 300℃, 3 hours, 400N conditions, yield load decreased compare to other conditions according to the over-aging phenomena. On the other hand, when arranged via AE amplitude results by K-means clustering pattern recognition of AE raw signals, tendency of signal strength appeared non-heat treatment condition, 'Class 1 < Class 2 < Class 3'; optimal condition, 'Class 3 < Class 2'; over-aging condition, 'Class 3 < Class 2 < Class 1'. This is judged by emitting a lot of AE energy when material causes plastic deformation because ductility increases on factor by over-aging phenomenon.
4,000원
8.
2010.03
구독 인증기관 무료, 개인회원 유료
Stainless steel sheets are widely used as the structure material for the railroad cars and the commercial vehicles. These kinds structures used stainless steel sheets are commonly fabricated by using the gas welding. For fatigue design of gas welded joints such as fillet and plug and ring type joint, it is important to obtain optimum design parameter information on gas welded joints. In this paper, analysis approach for fatigue test using experimental design are evaluated optimum factor in gas welded joint type and geometrical parameters of materials. Using these results, that factors applied to fundamental information for fatigue design.
4,000원
9.
2010.03
구독 인증기관 무료, 개인회원 유료
In general, electric powered wheelchair is used for handicapped persons as a means of movement. Electric powered wheelchair is controlled via joystick, which means that seriously handicapped person as vertebra damaged person can not use the general electric powered wheelchair. In this paper, a new navigation method for an intelligent electric powered wheelchair is proposed, which is very simple to implement by using the robotic technology. Two cameras are used in the system. The one is used for detecting obstacles in front of the wheelchair, and the other is used for detecting the intention of the user by measuring the movement of the head. A series of experiments are performed to evaluate the proposed method and the experimental results show that the proposed method can be applicable to the navigation of an intelligent electric powered wheelchair for seriously handicapped person of vertebra damage.
4,000원
<생산기술>
10.
2010.03
구독 인증기관 무료, 개인회원 유료
On cold start operation of an SI engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of spark timing and exhaust valve timing. Combustion stability is also considered at the same time. Experiments showed that retarded spark timing promotes the combustion at the end of expansion stroke and increases exhaust gas temperature during cold start.An advance of exhaust valve timing decreases residual gas in cylinders due to decrease of valve overlap period. It helps improvement combustion stability by virtue of reduced residual gas. A control strategy of proper valve timing and spark timing is suggested in order to achieve fast light-off of the catalyst and stable operation of the engine in a cold start and idle operation
4,000원
11.
2010.03
구독 인증기관 무료, 개인회원 유료
Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has the centrifugal roller and a ramp plate in the flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important claim which has an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study proposed an improved design of ramp plate reducing the wear of the centrifugal roller in order to provide some design guidelines.
4,000원
12.
2010.03
구독 인증기관 무료, 개인회원 유료
The developed network CAD system in this work has the sharing of functions, which consist of client and server. In recent years, distributed system has been applied to many industry to make a work cooperated. The developed system which consists of client and server as P2P type is implemented by COM/DCOM and CAD kernel technology to share the functions on network. Here, Requester is a client and provider is server. Developed system in this study is to share the functions among the systems with P2P structure. All systems which are linked on local network can use the functions of the other systems. The important things to construct this kind of distributed CAD system are transferring the 3D model data and accessing the location of providers. This system can perform many operations by using other systems multiply. Some of the operations performed and tested by the developed CAD system are Boolean operation, getting properties, triangulation and tessellation.
4,000원
