• 제목/요약/키워드: process diagnostics

검색결과 176건 처리시간 0.028초

저널베어링 상태 진단을 위한 최적의 데이터 분석 기준 설정 (Optimal Datum Unit Definition for Diagnostics of Journal Bearing System)

  • 윤병동;정준하;전병철;김연환;배용채
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.84-89
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    • 2014
  • Data-driven method for fault diagnostics system often use machine learning technique. To use such technique proper signal processing should be implemented such as time synchronous averaging (TSA) for ball bearing systems. However, for journal bearing diagnostics systems not much has been researched, and yet a proper signal processing method has not been studied. Therefore, in this research an optimal datum unit for a reliable journal bearing diagnostics system along with angular resampling process is being suggested. Before extracting time and frequency domain features, angular resampling is applied to each cycle of vibration data. As to preserve the characteristics of vibration signal, averaging method is replaced by finding the optimal datum unit which strengthens statistical characteristics of vibration signal. Then 20 features were extracted for various cases, and those features are being evaluated by two criteria, separability and classification accuracy.

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고도정수처리 과정에서 퍼클로레이트 이온의 농도 변화 (Perchlorate in Advanced Drinking Water Treatment Process)

  • 김현구;김정화;이연희;이재호;김산
    • 한국물환경학회지
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    • 제24권2호
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    • pp.164-168
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    • 2008
  • Perchlorate, which is still unregulated, is found in tap water, posing a threat to public health. In and out of Korea, there is no clear standard for drinking water quality or discharge. To make matters worse, Perchlorate study is in its infancy in Korea. This research tracked fresh water and purified water of water purification facility A and B located at the city of D, where Nak-dong River is being utilized as the purified water. And it was found that purified water shows no particular pattern in Perchlorate concentrations but represented a higher level of concentration compared to fresh water. With utilizing the research results, the study sought the impact of activated-carbon treatment process on Perchlorate elimination and found out that Perchlorate concentrations increased 38% after the process. The result proves that conventional water purification process can't eliminate Perchlorate. Therefore, it is reasonable that Perchlorate discharge from sources should be minimized.

Tribological diagnostics of machinery

  • Myshkin, N.K.
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1990년도 제11회 학술강연회초록집
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    • pp.7-31
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    • 1990
  • Tribologicsl diagnostics as the ensemble of means and methods of continuous monitoring of the state of friction characteristics of moving junctions is playing an ever important part in the development of friction, lubrication, and wear theory end practice. The scheme presenting the main areas of tribological diagnostics is given in Fig. I. This growing part of TD is determined by the general tendency of modern technology, expressed in an attempt to organically combine the functions of measuring, evaluating,and predicting the parameters and characteristics of the processee taking place in the operating device. The logical result of this integration in future is the closed system correcting its operation in accordance with sn established program. Unfortunately, tribotechnicsl devices are still very far from such an ideal system at the present time. While in the friction assemblies with hydrodynamic lubrication it is possible in the first approximation to realize feed-backs in the lubricant circulation system with the aid of monitoring of the pressure, temperature and filtration, in the systems operating without lubrication and with boundary lubricetion even the process of selection of the diagnostic parameters has not been completed.

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변증이론 선택을 위한 진단적 과정 (Steps Of Deciding ByunZheng(辨證))

  • 김태희
    • 대한한의진단학회지
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    • 제19권2호
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    • pp.109-113
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    • 2015
  • Byunzheng(辨證), 'Identification of Patterns' implies the process of identifying the original cause from symptoms and signs. Each symptom and sign has a meaning that manifests. But in Clinic, it is difficult to recognize the main cause through symptoms and signs by itself, because the patients complaint their symptoms differently. When considering Byunzheng, not only one symptom of one cause but relationship of manifested symptoms and causes are necessary. The object of Byunzheng is to diagnose Illness and disease through symptoms and signs and to coordinate Therapeutic Methods by Byunzheng. In Byunzheng, there are patterns according to the function of Internal Organs(臟腑), the Channels, the Eight Principles, the Five Elements and etc. Process to Diagnose Byunzheng is the most important. Until present, it is not clear to conclude the Byunzheng process or criteria. In certain case of Byunzheng is recognized by doctor's intuition, but most case is needed for conscious reasoning. Therefore, in this statement, process of conclude Byunzheng is reviewed rather than describing each character of Byunzheng.

ARMA 모델링과 스펙트럼분석법에 의한 가공시스템의 진단에 관한 연구 (A Study on Diagnostics of Machining System with ARMA Modeling and Spectrum Analysis)

  • 윤문철;조현덕;김성근
    • 한국생산제조학회지
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    • 제8권3호
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    • pp.42-51
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    • 1999
  • An experimental modeling of cutting and structural dynamics and the on-line detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics of cutting process but also for the analytic realization of diagnostic systems. In this regard, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision round shape machining such as turning, drilling and boring in mold and die making. In this study, simulation and experimental work were performed to show the malfunctioned behaviors. For this purpose, two new recursive approach (REIVM, RLSM) were adopted fur the on-line system identification and monitoring of a machining process, we can apply these new algorithm in real process for the detection of abnormal machining behaviors such as chipping, chatter, wear and round shape lobe waviness.

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Remote sensing and photogrammetry techniques in diagnostics of concrete structures

  • Janowski, Artur;Nagrodzka-Godycka, Krystyna;Szulwic, Jakub;Ziolkowski, Patryk
    • Computers and Concrete
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    • 제18권3호
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    • pp.405-420
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    • 2016
  • Recently laser scanning technologies become widely used in many areas of the modern economy. In the following paper authors show a potential spectrum of use Terrestrial Laser Scanning (TLS) in diagnostics of reinforced concrete elements. Based on modes of failure analysis of reinforcement concrete beam authors describe downsides and advantages of adaptation of terrestrial laser scanning to this purpose, moreover reveal under which condition this technology might be used. Research studies were conducted by Faculty of Civil and Environmental Engineering at Gdansk University of Technology. An experiment involved bending of reinforced concrete beam, the process was registered by the terrestrial laser scanner. Reinforced concrete beam was deliberately overloaded and eventually failed by shear. Whole failure process was tracing and recording by scanner Leica ScanStation C10 and verified by synchronous photographic registration supported by digital photogrammetry methods. Obtained data were post-processed in Leica Cyclone (dedicated software) and MeshLab (program on GPL license). The main goal of this paper is to prove the effectiveness of TLS in diagnostics of reinforced concrete elements. Authors propose few methods and procedures to virtually reconstruct failure process, measure geometry and assess a condition of structure.

온도 변화에 따른 압전체 센서 자가진단법 및 접합제의 영향에 대한 실험적 고찰 (The Effect of Temperature Variations and Bonding Agents on Piezoelectric Sensor Diagnostics)

  • 조혜진;박통일;박규해
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 추계학술대회 논문집
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    • pp.799-804
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    • 2013
  • The sensor/actuator active sensor diagnostics procedure, where the sensors/actuators are confirmed to be functioning properly during operation, is a critical component to successfully complete the structural health monitoring (SHM) process with large numbers of active sensors typically installed in a structure. The basis of this process is to track the changes in the capacitive value of piezoelectric materials, which shows up in measured admittance. Due to the temperature dependent nature of piezoelectric materials, we investigated the effects of temperature variations on sensor diagnostic process. The effect of temperature variations found to be remarkable, modifying the measured capacitive values significantly. In addition we analyzed the effect of bonding agents between a PZT patch and a host structure. This paper summarizes considerations needed to develop such sensor diagnostic processes, experimental procedures and results, and additional issues that can be used as guidelines for future investigations.

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채터모델링과 진단법에 관한 연구 (A Study on the Modeling and Diagnostics on Chatter in Endmilling Operation)

  • 김영국;윤문철;하만경;심성보
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.971-974
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    • 2001
  • In this study, the static and dynamic characteristics of endmilling process was modelled and the analytic realization of chatter mechanism was discussed. In this regard, We have discussed on the comparative assessment of recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision endmilling operation. In this study, simulation and experimental work were performed to show the malfunctional behaviors. For this purpose, new recursive(RLSM) were adopted for the on-line system identification and monitoring of a machining process, we can apply these new algorithms in real process for detection of abnormal chatter. Also, the stability lobe of chatter was analysed by varying parameter of cutting dynamices in regenerative chatter mechanics.

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Applications of DNA Microarray in Disease Diagnostics

  • Yoo, Seung-Min;Choi, Jong-Hyun;Lee, Sang-Yup;Yoo, Nae-Choon
    • Journal of Microbiology and Biotechnology
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    • 제19권7호
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    • pp.635-646
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    • 2009
  • Rapid and accurate diagnosis of diseases is very important for appropriate treatment of patients. Recent advances in molecular-level interaction and detection technologies are upgrading the clinical diagnostics by providing new ways of diagnosis, with higher speed and accuracy. In particular, DNA microarrays can be efficiently used in clinical diagnostics which span from discovery of diseaserelevant genes to diagnosis using its biomarkers. Diagnostic DNA microarrays have been used for genotyping and determination of disease-relevant genes or agents causing diseases, mutation analysis, screening of single nucleotide polymorphisms (SNPs), detection of chromosome abnormalities, and global determination of posttranslational modification. The performance of DNA-microarray-based diagnosis is continuously improving by the integration of other tools. Thus, DNA microarrays will play a central role in clinical diagnostics and will become a gold standard method for disease diagnosis. In this paper, various applications of DNA microarrays in disease diagnosis are reviewed. Special effort was made to cover the information disclosed in the patents so that recent trends and missing applications can be revealed.