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A Study of Arrow Performance using Artificial Neural Network (Artificial Neural Network를 이용한 화살 성능에 대한 연구)

  • Jeong, Yeongsang;Kim, Sungshin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.5
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    • pp.548-553
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    • 2014
  • In order to evaluate the performance of arrow that manufactures through production process, it is used that personal experiences such as hunters who have been using bow and arrow for a long time, technicians who produces leisure and sports equipment, and experts related with this industries. Also, the intensity of arrow's impact point which obtains from repeated shooting experiments is an important indicator for evaluating the performance of arrow. There are some ongoing researches for evaluating performance of arrow using intensity of the arrow's impact point and the arrow's flying image that obtained from high-speed camera. However, the research that deals with mutual relation between distribution of the arrow's impact point and characteristics of the arrow (length, weight, spine, overlap, straightness) is not enough. Therefore, this paper suggests both the system that could describes the distribution of the arrow's impact point into numerical representation and the correlation model between characteristics of arrow and impact points. The inputs of the model are characteristics of arrow (spine, straightness). And the output is MAD (mean absolute distance) of triangular shaped coordinates that could be obtained from 3 times repeated shooting by changing knock degree 120. The input-output data is collected for learning the correlation model, and ANN (artificial neural network) is used for implementing the model.

Measuring System for Impact Point of Arrow using Mamdani Fuzzy Inference System (Mamdani 퍼지추론을 이용한 화살의 탄착점 측정 시스템)

  • Yu, Jung-Won;Lee, Han-Soo;Jeong, Yeong-Sang;Kim, Sung-Shin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.4
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    • pp.521-526
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    • 2012
  • The performance of arrow from a manufacturing process depends on arrow's trajectory(archer's paradox) and intensity of an impact points. Especially, when conducting a shooting experiment over and over in the same experiment condition, the intensity of impact point is an objective standard to judge the performance of the arrow. However, the analysis method for the impact point is not enough, a previous research of the arrow's performance has been focused on a skill to optimize a manufacturing variables(feathers of an arrow, barb of an arrow, arrow's shaft, weight, external diameter, spine). In this paper, We propose measurement system of arrow's impact point with Mamdani fuzzy inference system and similarity of polygon for automation of impact point's measurement. Measuring the impact point data of the arrow moving with a high speed(approximately 275km/h) by using line laser and photo diode array, then the measured data are mapped to arrow's impact point with fuzzy inference and similarity of polygon.

Quality standard of Pleurotus ostreatus in a market and changes of mushroom quality during storage (유통 느타리버섯의 등급별 품질규격 및 저장기간별 품질 변화)

  • Lee, Chan-Jung;Oh, Jin-A;Cheong, Jong-Chun;Jhune, Chang-Sung;Moon, Ji-Won;Kong, Won-Sik;Suh, Jang-Sun
    • Journal of Mushroom
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    • v.11 no.4
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    • pp.287-291
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    • 2013
  • This study was carried out to improve standardization of agricultural products and investigate quality changes during storage at different treatments. The standardization does much to improve merchantable quality, distribution efficiency and fair dealings by shipping of the standard agricultural products. Therefore, modification of these standards is required to fit farmhouse situations. Average pileus diameter and thickness of A grades was 38.9 mm and 4.5 mm at shelf culture and 22.2 mm and 3.9 mm at bottle culture. Average stipe length of A grades was 49.6 mm at shelf culture and 66.7 mm at bottle culture, and stipes thick was the highest in A grades of shelf culture. The diameter of pileus of Pleurotus ostreatus stored for 14 days at $4^{\circ}C$ and $10^{\circ}C$ showed no significant difference. but the thickness of pileus decreased rapidly after 7 days. L-value and hardness of stipes and pileus were higher at shelf culture than bottle culture.