• 한국기계가공학회지
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• 제20권12호
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• pp.71-77
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• 2021

An impeller identification technique that is essential for adding viscosity measurement functions to overhead stirrers is presented in this study. Previous studies have revealed that using magnets facing the same poles arranged in a row can aid in distinguishing the types of impellers by detecting the number of magnets in a non-contact manner. However, as these previous studies measured the magnetic fields using analog Hall sensors, a converting circuit for the digital signals is required that can interface with the MCU. In this study, it was demonstrated that the number of magnets can be distinguished without using a separate conversion circuit by using a Hall sensor with a digital output. Owing to the unique hysteresis characteristics of digital Hall sensors, it was confirmed through experiments that the complex and diverse outputs appear depending on the direction of the magnetic field, the arrangement of magnetic poles, and the moving direction of the magnet. The measurement of the magnetic field showed that an edge signal equal to the number of magnets inserted into the impeller was detected when the radial direction was used, and the south pole was first approached.

• 임산에너지
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• 제19권1호
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• pp.30-37
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• 2000

This study was to analyze the chamical components of the pollens of Pinus rigida and P. koraensis and to investigate the optimal conditions for pollen pulverization. The results are as follow: (1) The contents of moisture, crude ash, crude protein, crude fat, crude filber and carbohydrate in the pollen of P. rigida were 9.9%, 2.5%, 13.1% 2.9% 7.5% 64.1% respectively, while those of P. koraiensis were 9.8%, 2.1%, 11.1% 2.8% 8.1% 66.1% respectively. All the contents of P. rigida and P. koraiensis were much higher than those of general crop grains. (2) Eighteen different amino acids were detected in the pollen of P. rigida and P. koraiensis. Among them, ten essential amino acids were indentified, which showed high nutritions values. (3) The contents of vitamin A, B1, B2, C, and E in the pollen of P. rigida were 8.7 mg, 10.1 mg, 15.9 mg, 32.9 mg, 1.9 mg, respectively, while those of in the pollen of P. koraiensis were 7.9 mg, 9.7 mg, 14.5 mg, 34.2 mg, and 2.5 mg respectively. Vitamin C among them was abundant. (4)When the pollen grains of P. prigida was pulverized for 50minutes at 5,000rpm and P. koraiensis for 40 minutes at 5,000rpm by Overhead stirrer, the 100% of pollen was pulverized.

• 한국기계가공학회지
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• 제18권2호
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• pp.52-57
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• 2019

To develop a stirring device that can automatically measure the viscosity of a fluid, the impeller type of the device must be recognized without making contact. In this study, we propose a method to discriminate the type of impellers using the changes in the magnetic field. Permanent magnets are inserted into a hollow hole of the impellers, and the change of the magnetic field is measured by a hall sensor. All experimental results are compared with the FEM analysis results. The results show that with the increase in diameter and length of the magnet inserted into the impeller, the magnitude of the magnetic flux density increases. The magnetic field is more sensitive to the change in the magnet diameter than to the change in magnet length. In order to reduce the machining costs, however, it is advantageous to change the magnet length instead of the magnet diameter.

• 임산에너지
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• 제18권2호
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• pp.47-54
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• 1999

소나무와 해송 화분에 대하여 화학적 성분을 분석하고 화분 파쇄 최적 조건을 구명하였던 바 다음과 같은 결과를 얻었다. (1)소나무 화분의 일반성분 함량은 수분 9.8%, 조회분 2.3%, 조단백질 11.9%, 조지방 2.9%, 조섬유 7.7%, 당질 65.4%이었으며, 해송 화분은 수분 10.5%, 조회분 2.2%, 조단백질 13.5%, 조지방 3.5%, 조섬유 8.5%, 당질 61.8%로서 일반곡류보다 높게 나타났다. (2)소나무와 해송 화분에서 각각 18종의 아미노산이 확인되었으며, 특히 10종의 필수아미노산을 포함하고 있어 영양원으로서 가치가 높은 것으로 나타났다. (3)소나무 화분은 비탄민 A 7.9㎎, B1 8.7㎎, B2 19.2㎎, C 31.5㎎, E 2.0㎎, 해송 화분은 비타민 A 8.5㎎, B1 9.4㎎, B2 15.7㎎, C 35.3㎎, E 1.8㎎ 함유하고 있었으며, 특히 비타민 C가 풍부하였다. (4)소나무 화분립은 5,000rpm으로 40분간, 해송 화분립은 5,000rpm으로 50분간 파쇄함으로써 100% 화분 파쇄가 가능하였다.