• 제목/요약/키워드: Center Identification

검색결과 2,368건 처리시간 0.219초

Cavitation state identification of centrifugal pump based on CEEMD-DRSN

  • Cui Dai;Siyuan Hu;Yuhang Zhang;Zeyu Chen;Liang Dong
    • Nuclear Engineering and Technology
    • /
    • 제55권4호
    • /
    • pp.1507-1517
    • /
    • 2023
  • Centrifugal pumps are a crucial part of nuclear power plants, and their dependable and safe operation is crucial to the security of the entire facility. Cavitation will cause the centrifugal pump to violently vibration with the large number of vacuoles generated, which not only affect the hydraulic performance of the centrifugal pump but also cause structural damage to the impeller, seriously affecting the operational safety of nuclear power plants. A closed cavitation test bench of a centrifugal pump is constructed, and a method for precisely identifying the cavitation state is proposed based on Complementary Ensemble Empirical Mode Decomposition (CEEMD) and Deep Residual Shrinkage Network (DRSN). First, we compared the cavitation sensitivity of pressure fluctuation, vibration, and liquid-borne noise and decomposed the liquid-borne noise by CEEMD to capture cavitation characteristics. The decomposition results are sent into a 12-layer deep residual shrinkage network (DRSN) for cavitation identification training. The results demonstrate that the liquid-borne noise signal is the most cavitation-sensitive signal, and the accuracy of CEEMD-DRSN to identify cavitation at different stages of centrifugal pumps arrives at 94.61%

Preparation and Identification of Crystal Modification of Piroxicam

  • Suh, Jung-Jin;Kim, Bong-Hee;Ko, Jung-Gil
    • Journal of Pharmaceutical Investigation
    • /
    • 제15권1호
    • /
    • pp.8-14
    • /
    • 1985
  • Data obtained from X-ray diffractometry, thermal analysis, IR spectroscopy and microscopic observation were used for the identification and characterization of four crystalline modifications of piroxicam. form a was crystallized from sodium hydroxide-hydrochloric acid and from c was obtained by crystallization from toluene. Form b and d was crystallized from methanol under the different temperature conditions. Relative rates of dissolution and solubility of four crystal forms of piroxicam in distilled water were measured.

  • PDF

Pulmonary Tuberculosis Diagnosis: Where We Are?

  • Leylabadlo, Hamed Ebrahimzadeh;Kafil, Hossein Samadi;Yousefi, Mehdi;Aghazadeh, Mohammad;Asgharzadeh, Mohammad
    • Tuberculosis and Respiratory Diseases
    • /
    • 제79권3호
    • /
    • pp.134-142
    • /
    • 2016
  • In recent years, in spite of medical advancement, tuberculosis (TB) remains a worldwide health problem. Although many laboratory methods have been developed to expedite the diagnosis of TB, delays in diagnosis remain a major problem in the clinical practice. Because of the slow growth rate of the causative agent Mycobacterium tuberculosis, isolation, identification, and drug susceptibility testing of this organism and other clinically important mycobacteria can take several weeks or longer. During the past several years, many methods have been developed for direct detection, species identification, and drug susceptibility testing of TB. A good understanding of the effectiveness and practical limitations of these methods is important to improve diagnosis. This review summarizes the currently-used advances in non-molecular and molecular diagnostics.

홍채 인식을 위한 동공 중심점 탐색 알고리즘에 관한 연구 (The Study on Searching Algorithm of the center of Pupil for the Iris Recognition)

  • 조민환;허정연
    • 한국컴퓨터정보학회논문지
    • /
    • 제11권1호
    • /
    • pp.19-25
    • /
    • 2006
  • 홍채인식은 개인의 홍채 패턴을 이용한 인식시스템으로 정보보안 분야나 개인 인증에 최고의 인증시스템중 하나로 알려져 있다. 홍채 인식을 위해 가장 먼저 해결해야하는 문제는 동공중심점탐색 이 매우 중요하다. 지금까지 많은 탐색 알고리즘들이 개발되었으나 대부분 처리시간이 매우 많이 소요된다. 본 논문에서는 새로운 동공 중심점 탐색 방법을 제시하고, Hough 변환을 이용한 방법과 비교하였다. 그 결과 120개의 이미지를 대상으로 실험한 결과 약 30%의 처리 속도 개선의 결과를 얻었다.

  • PDF

The Influence of Internet Use on Interpersonal Interaction among Chinese Urban Residents: The Mediating Effect of Social Identification

  • Chen, Hong;Qin, Jing;Li, Jing;Zheng, Guangjia
    • Asian Journal for Public Opinion Research
    • /
    • 제3권2호
    • /
    • pp.84-105
    • /
    • 2016
  • The instability of social norms on the Internet causes the diversity of social identification. Meanwhile, the anonymity of online social identity and the chaos of the role-playing among the interacting participants cause an ambiguity of identity recognition, which intensifies anxiety about interpersonal interaction. Methods that promote face-to-face interpersonal interaction through the reconstruction of the identification to the social system and intergroup trust is worth further research. Based on a telephone survey of urban residents in thirty-six cities in China (N=1080), the study focuses on the influence of Internet use on interpersonal interaction of urban residents and the mediation effect of social identification. The results show that Internet use has a negative effect on the interpersonal interactions of urban residents, and social identification plays a mediating effect between Internet use and interpersonal interaction. Implications of the results are discussed.

Comparative study on modal identification methods using output-only information

  • Yi, Jin-Hak;Yun, Chung-Bang
    • Structural Engineering and Mechanics
    • /
    • 제17권3_4호
    • /
    • pp.445-466
    • /
    • 2004
  • In this paper, several modal identification techniques for output-only structural systems are extensively investigated. The methods considered are the power spectral method, the frequency domain decomposition method, the Ibrahim time domain method, the eigensystem realization algorithm, and the stochastic subspace identification method. Generally, the power spectral method is most widely used in practical area, however, the other methods may give better estimates particularly for the cases with closed modes and/or with large measurement noise. Example analyses were carried out on typical structural systems under three different loading cases, and the identification performances were examined throught the comparisons between the estimates by various methods.

A comprehensive study on active Lamb wave-based damage identification for plate-type structures

  • Wang, Zijian;Qiao, Pizhong;Shi, Binkai
    • Smart Structures and Systems
    • /
    • 제20권6호
    • /
    • pp.759-767
    • /
    • 2017
  • Wear and aging associated damage is a severe problem for safety and maintenance of engineering structures. To acquire structural operational state and provide warning about different types of damage, research on damage identification has gained increasing popularity in recent years. Among various damage identification methods, the Lamb wave-based methods have shown promising suitability and potential for damage identification of plate-type structures. In this paper, a comprehensive study was presented to elaborate four remarkable aspects regarding the Lamb wave-based damage identification method for plate-type structures, including wave velocity, signal denoising, image reconstruction, and sensor layout. Conclusions and path forward were summarized and classified serving as a starting point for research and application in this area.

Molecular Identification of Korean Mountain Ginseng Using an Amplification Refractory Mutation System (ARMS)

  • In, Jun-Gyo;Kim, Min-Kyeoung;Lee, Ok-Ran;Kim, Yu-Jin;Lee, Beom-Soo;Kim, Se-Young;Kwon, Woo-Seang;Yang, Deok-Chun
    • Journal of Ginseng Research
    • /
    • 제34권1호
    • /
    • pp.41-46
    • /
    • 2010
  • Expensive herbs such as ginseng are always a possible target for fraudulent labeling. New mountain ginseng strains have occasionally been found deep within mountain areas and commercially traded at exorbitant prices. However, until now, no scientific basis has existed to distinguish such ginseng from commonly cultivated ginseng species other than by virtue of being found within deep mountain areas. Polymerase chain reaction (PCR) analysis of the internal transcribed spacer has been shown to be an appropriate method for the identification of the most popular species (Panax ginseng) in the Panax ginseng genus. A single nucleotide polymorphism (SNP) has been identified between three newly found mountain ginseng (KGD4, KGD5, and KW1) and already established Panax species. Specific PCR primers were designed from this SNP site within the sequence data and used to detect the mountain ginseng strains via multiplex PCR. The established multiplex-PCR method for the simultaneous detection of newly found mountain ginseng strains, Korean ginseng, and foreign ginseng in a single reaction was determined to be effective. This study is the first report of scientific discrimination of "mountain ginsengs" and describes an effective method of identification for fraud prevention and for uncovering the possible presence of other, cheaper ginseng species on the market.

Basic Tongue Diagnosis Indicators for Pattern Identification in Stroke Using a Decision Tree Method

  • Lee, Ju Ah;Lee, Jungsup;Ko, Mi Mi;Kang, Byoung-Kab;Lee, Myeong Soo
    • 대한한의학회지
    • /
    • 제33권4호
    • /
    • pp.1-8
    • /
    • 2012
  • Objectives: The purpose of this study was to specify major tongue diagnostic indicators and evaluate their significance in discriminating pattern identification subtypes in stroke patients. Methods: This study used a community based multi-center observational design. Participants (n=1,502) were stroke patients admitted to 11 oriental medical university hospitals between December 2006 and February 2010. To determine which tongue indicator affected each pattern identification, a decision tree analysis of the chi-square automatic interaction detector (CHAID) algorithm was performed. The chi-squared test was used as the criterion in splitting data with a p-value less than 0.05 for division, which is the main procedure for developing a decision tree. The minimum sample size for each node was specified as n =10, and branching was limited to two levels. Results: From the 9 tongue diagnostic indicators, 6 major tongue indicators (red tongue, pale tongue, yellow fur, white fur, thick fur, and teeth-marked tongue) were identified through the decision tree analysis. Furthermore, each pattern identification was composed of specific combinations of the 6 major tongue indicators. Conclusions: This study suggests that the 6 tongue indicators identified through the decision tree analysis can be used to discriminate pattern identification subtypes in stroke patients. However, it is still necessary to re-evaluate other pattern identification indicators to further the objectivity and reliability of traditional Korean medicine.

변증 설문지 문항을 통해 살펴 본 알레르기 비염 환자의 특성 (Characteristics of Patients with Allergic Rhinitis through the Pattern Questionnaire Items)

  • 손재웅;이규진;장보형;장수빈;고성규;최인화
    • 대한예방한의학회지
    • /
    • 제18권3호
    • /
    • pp.81-90
    • /
    • 2014
  • Objective : We performed a clinical study to investigate pattern characteristics in persistent allergic rhinitis depending on Korean Medicine pattern questionnaire items as a pattern identification diagnostic tool. Method : 32 patients with persistent allergic rhinitis were asked to interview with doctor of Korean Medicine and perform the 4 pattern questionnaires(Cold-Heat Pattern, Phlegm Pattern, Yin Deficiency pattern, bloodstasis pattern). Then, we analyzed the response rate of each pattern questionnaires. Results : After diagnosis of Korean Medicine Doctor's pattern identification, 17 individual items have higher response rate, 7 of 17 items have a common tendency in allergic rhinitis. The other 8 of 10 items belong to Lung qi deficiency cold and Lung-spleen qi deficiency group, these have higher tendency of deficiency. In bloodstasis pattern questionnaires, we don't decide the tendency of patients with allergic rhinitis. Conclusion : The result may provide that we don't use Korean Medicine pattern questionnaires as a major tool in the pattern identification of allergic rhinitis. Continuous studies are needed to develop the standardized pattern identification diagnostic tool.