• Title/Summary/Keyword: Final speed

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A study on the estimation of impact velocity of crashed vehicles in tunnel using computer simulation(PC-CRASH) (컴퓨터 시뮬레이션(PC-CRASH)을 이용한 터널 내 피추돌 차량의 충돌 속도 추정에 관한 연구)

  • Han, Chang-Pyoung;Choi, Hong-Ju
    • Design & Manufacturing
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    • v.14 no.4
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    • pp.40-45
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    • 2020
  • In a vehicle-to-vehicle accident, the impact posture, braking status, final stopping position, collision point and collision speed are important factors for accident reconstruction. In particular, the speed of collision is the most important issue. In this study, the collision speed and the final stopping position in the tunnel were estimated using PC-CRASH, a vehicle crash analysis program used for traffic accident analysis, and the final stopping position of the simulation and the final stopping position of the traffic accident report were compared. When the Pride speed was 0km/h or 30km/h and the Sorento speed was 100m/h, the simulation results and reports matched the final stopping positions and posture of the two vehicles. As a result of the simulation, it can be estimated that Pride was collided in an almost stationary state.

Improvement of Productivity for the high carbon steel wire(0.75wt%C) through the Superhigh Speed Drawing (초고속 신선을 통한 고탄소강(0.75wt%C) 선재의 생산성 향상에 관한 연구)

  • Lee, Sang-Kon;Kim, Byung-Min;Lee, Sang-Jin
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1632-1636
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    • 2007
  • Generally, fine high carbon steel wire is produced using a multi-pass drawing process with speeds over 1000 m/min. The productivity of the wire drawing mainly depends on achieving the highest drawing speed without breaking the wire. In the multi-pass drawing, as the final drawing speed increases, the temperature rises several hundred Celsius. High temperature of wire increases the brittleness and leads to breaks. The objective of this study is to design pass schedule and wire drawing machine for superhigh speed. In the drawing experiment, it was possible to increase the productivity through the increase in final speed from 1100 m/min to 2000 m/min.

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Load Characteristics of Rotary Operation Using a Cage Wheel in Wet Paddy Fields (케이지 휠을 이용한 습답 로터리 작업의 부하 특성)

  • 오영근;김경욱;박금숙
    • Journal of Biosystems Engineering
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    • v.26 no.3
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    • pp.229-236
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    • 2001
  • The torque loads acting on the input shaft of the transmission and final driving shaft of the tractor having a cage wheel attached to the driving tries as a traction aid were measured during the rotavating operations in a poorly drained paddy field. Using the measured load data load spectra were constructed. Effects of the design parameters of the cage wheel on the load characteristics were also analyzed. The torque load exerted on the input shaft decreased as the diameter of the cage wheel increased and increased as the rotavator speed increased. The torque load exerted on the final driving shaft increased as the working speed of the tractor increased and decreased as the rotavator speed increased. The torque load on the final driving shaft with the cage wheel were greater than those without the cage wheel.

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A Study on the Calculation of the FPM for the Descent Angle (강하각 유지를 위한 강하율 산정 연구)

  • Kyung-Han Lee;Sung-Yeob Kim;Ji-Hun Choi
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.31 no.2
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    • pp.1-6
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    • 2023
  • When landing an aircraft descent-speed, wind around the airport, and regulations are important indicators for the pilot to decide whether to land in the Final Approach. In this study, in order to maintain a decent angle accessible to the airport, the pilot predicts an appropriate decent rate suitable for wind direction, wind speed, and speed to make a stable landing. To confirm this, the decent rate according to the speed and speed of wind was calculated using the information actually measured on the B737NG aircraft and compared with the theoretical figures. The purpose of this study is to ensure that the pilot can make a stable landing at a given FPM (Feet Per Minute) when a visual approach and non-normal approach is required at an airport designed with a somewhat higher descent angle.

A Study on the Prediction of the Final Weight for the Injection Molded Rectangular Plates (사각판 사출성형품의 최종무게 예측에 관한 연구)

  • Lee, Chang-Hoon;Yoon, Kyunghwan
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.9
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    • pp.130-137
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    • 1996
  • In the present paper the effect of various process conditions on the final weight of injection molded rectangular plates has been investigated in detail. The main parameters involved in the simulations were melt temperature, mold temperature, injection speed and packing pressure. The dimensions of the plate used were 100mm long, 2mm of width and polystyrene was used as a molding material. The shear viscosity of the polymeric material was treated as a function of shear rate, temperature and pressure through the whole processes including packing and cooling stages. By increasing a packing pressure the final weight of sample increased linearly. Furthermore, as the melt temperature, the mold temperature and the injection speed increased, the final weight of the injection molded plate decreased within the molding window.

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Speed Control of D.C Motor based on Deadbeat Response (직류 전동기의 유한 시간 정정 응답 제어)

  • Kim, Young-Seok;You, Wan-Sik
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.371-374
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    • 1990
  • This paper presents the speed control of dc motor based on deadbeat response. The deadbeat response is that the output reaches the final value in the minimum possible settling time and stays there. This results demonstrate that the output reaches final value in one sampling time for the unsaturated region, and in one sampling time after getting free from the saturation state for the saturated region.

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Development of Continuous Cross-Flow Rice Drying Model and Drying Speed Control System Using Fuzzy Logic(II) - Drying Speed Control - (벼의 횡류 연속식 건조 모델 개발과 퍼지논리를 이용한 건조 속도 제어에 관한 연구(II) - 건조속도제어 -)

  • 송대빈;고학균;조성인
    • Journal of Biosystems Engineering
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    • v.23 no.5
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    • pp.457-464
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    • 1998
  • A drying speed control system using fuzzy logic was developed in order to minimize the damage of rice quality for a large capacity continuous dryer. The performance of the system was tested at two object moisture content of 17% and 25% on a wet basis. For object moisture content of 17% on a wet basis, the final output moisture contents from 20.46%, 20.96%, 18.98% on a wet basis were 17.99%, 17.6% and 17.23% on a wet basis, respectively. For object moisture content of 25% on a wet basis, the final output moisture contents from 28.85%, 26.95%, 28.11%, 27.8% on a wet basis were 25.24%, 24.9%, 25.23% and 25.09% on a wet basis, respectively.

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High Speed Character Recognition by Multiprocessor System (멀티 프로세서 시스템에 의한 고속 문자인식)

  • 최동혁;류성원;최성남;김학수;이용균;박규태
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.2
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    • pp.8-18
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    • 1993
  • A multi-font, multi-size and high speed character recognition system is designed. The design principles are simpilcity of algorithm, adaptibility, learnability, hierachical data processing and attention by feed back. For the multi-size character recognition, the extracted character images are normalized. A hierachical classifier classifies the feature vectors. Feature is extracted by applying the directional receptive field after the directional dege filter processing. The hierachical classifier is consist of two pre-classifiers and one decision making classifier. The effect of two pre-classifiers is prediction to the final decision making classifier. With the pre-classifiers, the time to compute the distance of the final classifier is reduced. Recognition rate is 95% for the three documents printed in three kinds of fonts, total 1,700 characters. For high speed implemention, a multiprocessor system with the ring structure of four transputers is implemented, and the recognition speed of 30 characters per second is aquired.

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Extrusion Puffing of Pork Meat-Defatted Soy Flour-Corn Starch Blends to Produce Snack-like Products

  • Jennifer J. Jamora;Rhee, Ki-Soon;Rhee, Khee-Choon
    • Preventive Nutrition and Food Science
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    • v.6 no.3
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    • pp.163-169
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    • 2001
  • To produce expanded, minimally hard extrudates from blends of raw pork meat (20%), defatted soy flour (25%), and corn starch using a single-screw extruder, various combinations of feed moisture, process temperature, and screw speed were evaluated. First series of extrusion runs were conducted according to a central composite rotatable design/response surface methodology (RSM). Upon assessing the full model for each response, insignificant terms were eliminated to determine final response surface models. Screw speed within the range evaluated was found to have no significant effect on expansion ratio (ER) or shear force (SF) of extrudates. Since examinations of the response surfaces and their generated grids of predicted values indicated that maximum ER and minimum SF were likely to be attained with a moisture-temperature combination outside the RSM experimental range, the second series of extrusion runs were conducted with several selected combinations of moisture and temperature to determine a practical optimum extrusion condition. The combination of 22.78% feed moisture, 16$0^{\circ}C$ process temperature, and 170 rpm screw speed was chosen as such a condition, and used in the final extrusion. The final product required less force to break than did commercial pretzel sticks.

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Pass Schedule Design for Improvement of Drawing Speed in the Dry Wire Drawing Process (신선 속도 향상을 위한 건식 신선 공정의 패스스케줄 설계)

  • 김영식;김동환;김병민;김민안;박용민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.600-603
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    • 2000
  • In the high carbon steel wire drawing process, the wire temperature increases as the drawing speed is faster in order to increase the production rate in the shop floor. The rapid temperature rise causes the wire fracture in the dry wire drawing process. So, in this paper, the isothermal pass schedule program, which includes the calculation method of wire temperature at each pass, is proposed to prevent the wire fracture due to the temperature rise. Using the isothermal pass schedule program, it is newly proposed the pass schedule design system that prevents the cup-cone defects, improves the elongation of the final products and assures further deformation. As a result, the temperature rise of the wire was decreased and the production rate of the final product is remarkably grown up according to the increase of the final drawing speed than that of the conventional process. Also, the proposed pass schedule design system could give a useful information to the process designer who would design the high carbon steel wire drawing process.

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