• Title/Summary/Keyword: Low specific speed

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A Study on Prevention of Explosion Accidents (폭발재해 예방대책에 관한 소고)

  • Kim In Sung
    • Explosives and Blasting
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    • v.12 no.3
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    • pp.32-41
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    • 1994
  • The specific characters in recent Chemical processing and industrial plants are the handling of severe limit conditions such as high pressure, high and low temperature, high speed production and transportation plant automation and appearance of many new hazardous materials in numbers and quantity. The possibilities of these characters causing the accident and environmental pollution in industrial activities become very high. This paper describes the concrete policy In prevent the explosion accident out of the many accidents which are the safety of the safety engineering.

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Operating Characteristics Analysis of Disk type Single-phase SRM (디스크형 단상 SRM의 동작 특성 해석)

  • Lee, Jong-Han;Oh, Young-Woong;Lee, Eun-Woong
    • Proceedings of the KIEE Conference
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    • 1999.07a
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    • pp.191-193
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    • 1999
  • The various advantages of DSPSRM lie in constructional simplicity, robustness and low cost. Also it has a specific characteristic of axial flux machine and radial flux machine simultaneously. In this paper, we designed and manufactured its operating drive and measured the characteristics of torque, efficiency, current to speed.

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Collision Response of Bow Structure and Its Affected Collision Bulkhead in Bow Collision (선수 충돌시 구조거동과 충돌격벽에 미치는 영향)

  • 신영식;박명규
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.04a
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    • pp.195-204
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    • 2000
  • In this paper a complicated structural behavior in collision and its effect of energy translation to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against head on collision. In the present the bow structure is normally designed in consideration of its specific structural arrangements and internal and external loads in these area such as hydrostatic and dynamic pressure, wave impact and bottom slamming in accordance with the Classification rules, and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits, and by the result of these simulation it provides the optimal design concept for the low construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

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A Study on Surface roughness in High speed face milling machining of Al2024 (Al2024의 고속 정면밀링 가공에서 표면 거칠기에 관한 연구)

  • Jang, Sung-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.603-608
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    • 2014
  • In many manufacturing such as the components of airplane and automobile, aluminum alloys(Al2024) which remarkable in low specific gravity and high strength have been utilized effectively. Face milling machining technology for surface roughness quality of workpiece has been applied in these fields. A face milling machining with chamfered throw away type insert tip can produce a perfect flat surface only in theory. But It is impossible because of many unwanted factors, namely, cutting temperature, plastic deformation, dynamic effect, etc. In this paper, experimental investigations are performed to improve surface roughness after high speed machining of Al2024 using qualified face milling cutter body for high speed machining.

Distinctive Point Extraction and Recognition Algorithm for Various Kinds of Euro Banknotes

  • Lee, Jae-Kang;Jeon, Seong-Goo;Kim, Il-Hwan
    • International Journal of Control, Automation, and Systems
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    • v.2 no.2
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    • pp.201-206
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    • 2004
  • Counters for the various kinds of banknotes require high-speed distinctive point extraction and recognition. In this paper we propose a new point extraction and recognition algorithm for Euro banknotes. For distinctive point extraction we use a coordinate data extraction method from specific parts of a banknote representing the same color. To recognize banknotes, we trained 5 neural networks. One is used for inserting direction and the others are used for face value. The algorithm is designed to minimize recognition time by using a minimal amount of recognition data. The simulated results show a high recognition rate and a low training period. The proposed method can be applied to high speed banknote counting machines.

Vibration Analysis of Driveline with Propeller Shaft Supported by Center Bearing when the Vehicle Starts (추진축이 센터베어링으로 지지된 차량 구동계의 출발시 진동해석)

  • 이창노;김효준
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.1043-1048
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    • 2002
  • This paper considers the vibration problem of vehicle driveline which consists of two propeller shafts and the center bearing. The excessive vibration occurs at the center bearing when the vehicle starts to run. Using the kinematic constraints at the universal joint between two propeller shafts, we develop an one d.o.f model which describes the radial motion of the center bearing. We find out the vibration occurs at the specific vehicle speed corresponding to the natural frequency of the model. Comparing the simulation results with test results we also show that the vibration at low vehicle speed is caused primarily by the joint angle and secondarily by the mis-aligned yoke flange rather than by the unbalance.

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Test for Lubricity Evaluation by Cold Rolling Tribosimulator (냉간압연Tribo-Simulator에 의한 냉간압연유 윤활성 평가시험)

  • Kim Chul-Hee
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2003.11a
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    • pp.158-163
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    • 2003
  • Several simulation techniques have been developed which are not practical deformation processes but are designed to embody specific tribological aspects. Sliding rolling type friction test machine (Cold rolling tribosimulator) was developed to simulate the tribological phenomena at the roll bite in real mill by laboratory scale. A rolled material is fed at a low speed of Max. 1/20 to that of roll speed, so as to obtain simultaneous plastic deformation in the material during rotation of the rolls in simulator. New cold rolling tribe-simulator is effective for evaluation of the lubricity of lubricant in cold rolling process.

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Vibration Analysis of Driveline with Propeller Shaft Supported by Center Bearing when the Vehicle Starts Up (센터 베어링으로 지지된 추진축을 갖는 구동계의 차량 출발시 진동해석)

  • Lee, Chang-Ro;Kim, Hyo-Jun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.12
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    • pp.929-934
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    • 2002
  • This paper considers the vibration Problem of vehicle driveline which consists of two propeller shafts and the center bearing. The excessive vibration occurs at the center bearing when the vehicle starts to run. Using the kinematic constraints at the universal joint between two propeller shafts, we developed an one d.o.f model which describes the radial motion of the center bearing. We found out that the vibration occurs at the specific vehicle speed corresponding to the natural frequency of the model. Comparing the simulation results with test results we also show that the vibration at low vehicle speed is caused primarily by the feint angle and secondarily by the mis-aligned yoke flange rather than by the unbalance.

A Study on Engine Performance Characteristics with Variation of Operating Condition in Diesel Engine (디젤엔진의 운전인자 변화에 따른 엔진의 성능특성에 관한 연구)

  • Kim, GiBok
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.4_2
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    • pp.645-651
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    • 2020
  • In this study, It is necessary that we should study on more effective use about reciprocating engines because there are huge increase of air pollution. Diesel Engine is operated by injecting fuel directly to combustion chamber with high pressure. Diesel Engine has greater thermal efficiency and durability than Gasoline Engine. Also, Diesel Engine emitted low harmful exhaust witch caused by Gasoline Engine. There are many ways to improve of performance and decrease of harmful exhaust by controlling injection timing, changing amount of fuel and engine speed and so on. Especially, development and application of common rail direct injection Engine cause the increase of thermal efficiency by controlling a various of operating conditions. In this study we analyze characteristics of performance by changing a various of operating conditions.

Low energy and area efficient quaternary multiplier with carbon nanotube field effect transistors

  • Rahmati, Saeed;Farshidi, Ebrahim;Ganji, Jabbar
    • ETRI Journal
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    • v.43 no.4
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    • pp.717-727
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    • 2021
  • In this study, new multiplier and adder method designs with multiplexers are proposed. The designs are based on quaternary logic and a carbon nanotube field-effect transistor (CNTFET). The design utilizes 4 × 4 multiplier blocks. Applying specific rotational functions and unary operators to the quaternary logic reduced the power delay produced (PDP) circuit by 54% and 17.5% in the CNTFETs used in the adder block and by 98.4% and 43.62% in the transistors in the multiplier block, respectively. The proposed 4 × 4 multiplier also reduced the occupied area by 66.05% and increased the speed circuit by 55.59%. The proposed designs are simulated using HSPICE software and 32 nm technology in the Stanford Compact SPICE model for CNTFETs. The simulated results display a significant improvement in the fabrication, average power consumption, speed, and PDP compared to the current bestperforming techniques in the literature. The proposed operators and circuits are evaluated under various operating conditions, and the results demonstrate the stability of the proposed circuits.