• Title/Summary/Keyword: Machinery Industry

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Abnormal Vibration Diagnostics Algorithm of Rotating Machinery Using Self-Organizing Feature Map nad Learing Vector Quantization (자기조직화특징지도와 학습벡터양자화를 이용한 회전기계의 이상진동진단 알고리듬)

  • 양보석;서상윤;임동수;이수종
    • Journal of KSNVE
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    • v.10 no.2
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    • pp.331-337
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    • 2000
  • The necessity of diagnosis of the rotating machinery which is widely used in the industry is increasing. Many research has been conducted to manipulate field vibration signal data for diagnosing the fault of designated machinery. As the pattern recognition tool of that signal, neural network which use usually back-propagation algorithm was used in the diagnosis of rotating machinery. In this paper, self-organizing feature map(SOFM) which is unsupervised learning algorithm is used in the abnormal defect diagnosis of rotating machinery and then learning vector quantization(LVQ) which is supervised learning algorithm is used to improve the quality of the classifier decision regions.

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STATUS AND PROSPECTS OF AGRICULTURAL MECHANIZATION IN CHINA

  • Gao, Yuanen;Wei, Songling
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.76-92
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    • 1996
  • In China, agricultural mechanization has played a remarkable, role in development of agricultural economy. This paper introduces briefly the contribution of agricultural mechanization to agricultural production , the level of mechanization , sciences and research , industry of farm machinery etc., at present. From macro view , aim at year 2000 , the prospects based on estimation concerned with the developing tendency , market demands, research fields are presented . The development of agricultural mechanization in China depends on many factors, in coming years, chance and challenge are coexistent. It wall take a long time for China to realize farm mechanization.

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Abnormal Vibration Diagnosis of rotating Machinery Using Self-Organizing Feature Map (자기조직화 특징지도를 이용한 회전기계의 이상진동진단)

  • Seo, Sang-Yoon;Lim, Dong-Soo;Yang, Bo-Suk
    • 유체기계공업학회:학술대회논문집
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    • 1999.12a
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    • pp.317-323
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    • 1999
  • The necessity of diagnosis of the rotating machinery which is widely used in the industry is increasing. Many research has been conducted to manipulate field vibration signal data for diagnosing the fault of designated machinery. As the pattern recognition tool of that signal, neural network which use usually back-propagation algorithm was used in the diagnosis of rotating machinery. In this paper, self-organizing feature map(SOFM) which is unsupervised learning algorithm is used in the abnormal vibration diagnosis of rotating machinery and then learning vector quantization(LVQ) which is supervised teaming algorithm is used to improve the quality of the classifier decision regions.

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Characteristic of Makgeolli and Pine (Pinus koraiensis) Extract Fermentation (소나무 (Pinus koraiensis) 추출물과 결합 된 막걸리 발효의 특징)

  • Destiani, Supeno;Kwo, Soon Hong;Chung, Sung Won;Kwon, Soon Goo;Park, Jong Min;Kim, Jong Soon;Choi, Won Sik
    • Journal of the Korean Society of Industry Convergence
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    • v.20 no.5
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    • pp.377-383
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    • 2017
  • In this research, the improvement of Korean rice wine (makgeolli) with pine (Pinus koraiensis) extract addition was evaluated due to the increase in alcoholic Korean traditional beverage. Makgeolli fermentation was prepared using Korean rice and nuruk (traditional starter) supplemented by pine needle (MPN) and pine sprout (MPS) extract. The average of initial pH level for MPN was 3.95 and MPS was 4.55, the average of initial sugar content for MPN was 0.4% and MPS was 0.3%. The sugar content and pH level behavior were investigated every 24h during fermentation period. The observation of microbial colony was done at days 8 of fermentation period with three time sample dilution. Afterward, the physical appearance of fermentation solution and microbial development were investigated in the final of fermentation period. The number of yeast and LAB ($402{\times}103\;CFU/mL$) in MPN was greater than the yeast and LAB count in MPS ($224{\times}103\;CFU/mL$). The pH level obtained by addition pine sprout have value of R2 higher than addition of pine needles (leaf), the sugar content (%) behaviour was opposite with pH level behaviour.

Rotordynamic Characteristics of Floating Ring Seals in Rocket Turbopumps

  • Tokunaga, Yuichiro;Inoue, Hideyuki;Hiromatsu, Jun;Iguchi, Tetsuya;Kuroki, Yasuhiro;Uchiumi, Masaharu
    • International Journal of Fluid Machinery and Systems
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    • v.9 no.3
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    • pp.194-204
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    • 2016
  • Floating ring seals offer an opportunity to reduce leakage flows significantly in rotating machinery. Accordingly, they have been applied successfully to rotating machinery within the last several decades. For rocket turbopump applications, fundamental behavior and design philosophy have been revealed. However, further work is needed to explore the rotordynamic characteristics associated with rotor vibrations. In this study, rotordynamic forces for floating ring seals under rotor's whirling motions are calculated to elucidate rotordynamic characteristics. Comparisons between numerical simulation results and experiments demonstrated in our previous report are carried out. The three-dimensional Reynolds equation is solved by the finite-difference method to calculate hydrodynamic pressure distributions and the leakage flow rate. The entrance loss at the upstream inlet of the seal ring is calculated to estimate the Lomakin effect. The friction force at the secondary seal surface is also considered. Numerical simulation results showed that the rotordynamic forces of this type of floating ring seal are determined mainly by the friction force at the secondary seal surface. The seal ring is positioned almost concentrically relative to the rotor by the Lomakin effect. Numerical simulations agree quite well with the experimental results.

Research on unsupervised condition monitoring method of pump-type machinery in nuclear power plant

  • Jiyu Zhang;Hong Xia;Zhichao Wang;Yihu Zhu;Yin Fu
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2220-2238
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    • 2024
  • As a typical active equipment, pump machinery is widely used in nuclear power plants. Although the mechanism of pump machinery in nuclear power plants is similar to that of conventional pumps, the safety and reliability requirements of nuclear pumps are higher in complex operating environments. Once there is significant performance degradation or failure, it may cause huge security risks and economic losses. There are many pumps mechanical parameters, and it is very important to explore the correlation between multi-dimensional variables and condition. Therefore, a condition monitoring model based on Deep Denoising Autoencoder (DDAE) is constructed in this paper. This model not only ensures low false positive rate, but also realizes early abnormal monitoring and location. In order to alleviate the influence of parameter time-varying effect on the model in long-term monitoring, this paper combined equidistant sampling strategy and DDAE model to enhance the monitoring efficiency. By using the simulation data of reactor coolant pump and the actual centrifugal pump data, the monitoring and positioning capabilities of the proposed scheme under normal and abnormal conditions were verified. This paper has important reference significance for improving the intelligent operation and maintenance efficiency of nuclear power plants.