• 제목/요약/키워드: Tool Condition Monitoring

검색결과 179건 처리시간 0.026초

건설업 안전보건경영시스템 실행의 성숙도 분석 (The Analysis of Maturity on Implementation of Safety and Health Management System in a Construction Company)

  • 오병섭;권창희
    • 한국재난정보학회 논문집
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    • 제8권3호
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    • pp.310-318
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    • 2012
  • 본 연구의 목적은 국내 안전보건경영시스템의 올바른 정착과 지속적인 개선을 통한 산업재해를 줄이기 위한 시스템 성숙도평가를 제안하는데 있다. KOSHA 18001시스템 실행의 현재 수준파악과 성숙도 측정의 검증을 통한 결과로서 다음 내용으로 요약된다. 시스템의 지속적인 성숙도 등급 향상을 위해서는 경영층 인식부문(의사결정) 46.0%, 본사지원활동 32.0%, 현장실행참여 22.0%로 중요도 로 검증되었다. 본사/현장의 활동은 위험성평가, 안전보건 재해예방활동, 성과평가 및 모니터링, 자원관리 및 지원, 경영검토 및 개선 등 활동의 중요도 순으로 실행 우선순위가 결정되었다. 또한, 전문가 그룹은 시스템의 강점, 약점, 개선주제를 제시함으로써 지속적인 개선활동과 연계시켜야 시스템을 정착할 수 있다고 제시하였다. 셋째, 안전보건경영시스템 실행의 성숙도 등급을 관리할 수 있는 도구를 제시하였다.

축방향 누설자속 측정에 의한 유도전동기의 회전자 결함검출에 관한 연구 (A Study of Rotor Fault Detection for the Induction Motor Using Axial Leakage Magnetic Flux)

  • 신대철;김영환
    • 조명전기설비학회논문지
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    • 제20권1호
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    • pp.132-137
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    • 2006
  • 유도전동기에 대한 결함 검출의 도구로서 축방향 누설자속 측정 방법을 사용할 수 있는가를 평가하고 전동기고장 검출에 관한 진단 알고리즘을 개발하기 위한 회전자에 관한 2번째 논문이다. 결함 검출을 위해 운전 중인 전동기의 끝단에 설치된 자속코일 센서로 누설자속 신호를 수집하며 전동기의 각종 결함을 검출하기 위해 시간과 주파수 영역에서 신호를 분석하였다. 센서 신호 형상이 전동기 각각의 결함에 대해 시간과 주파수 영역에서 해석하였다. 전동기의 회전자 관련 격함인 회전자봉 파손, 단락환 파손 및 회전자 편심이 축방향에서 측정된 고해상도의 스펙트럼으로부터 검출할 수 있는 방법을 확인하였다. 누설자속 스펙트럼으로부터 특정 주파수와 회전자봉 통과주파수의 측파대를 분석함으로서 회전자 결함을 검출하는 방법을 알았다. 또 유도전동기에 대하여 축방향 누설자속 측정을 위한 최적의 자속코일센서 및 측정시스템을 검증하고 회전자 결함을 검출하기 위한 방법을 개발하였다.

젖소에서 유성분 분석을 통한 우군 건강관리프로그램의 개발 (Development of program for herd health management by milk components analysis of dairy cows)

  • 문진산;손창호;이보균;주이석;강현미;김종만;김병태;문현식
    • 대한수의학회지
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    • 제42권4호
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    • pp.485-493
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    • 2002
  • The purpose of this study was to develope a computer program to help with gross diagnosis of protein-energy balance and feeding management practice and with the prediction about the risk possibility of productive disease such as reproductive and metabolic disorders by evaluating fat, protein, and milk urea nitrogen (MUN) from individual cow milk in dairy herd Somatic cell counts also represent the condition of udder health. The principal flow charts of this program was to check on herd management, sampling the composite milk, analysis the milk composition, conversion of data from milking equipment to program, input and analysis of data in program, and report. This program is compatible with window 95/98 system. The major analytical elements of this program were presented as; the profile of herd lactation curve analysis of the test-day milk production level, the distribution of somatic cell count, the fat to protein ratio to evaluate body energy balance, and the interpretation of dietary protein-energy balance by milk protein and MUN contents for individual cows. This program using milk fat, protein, MUN, and somatic cell counts will serve as a monitoring tool for the protein-energy balance and the feeding management practice, and for distribution of mastitis in individual cows. It will also be used to manage the nutritional and reproductive disorders and mastitis at the farm level.

Stator Current Processing-Based Technique for Bearing Damage Detection in Induction Motors

  • Hong, Won-Pyo;Yoon, Chung-Sup;Kim, Dong-Hwa
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1439-1444
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    • 2005
  • Induction motors are the most commonly used electrical drives because they are rugged, mechanically simple, adaptable to widely different operating conditions, and simple to control. The most common faults in squirrel-cage induction motors are bearing, stator and rotor faults. Surveys conducted by the IEEE and EPRI show that the most common fault in induction motor is bearing failure (${\sim}$40% of failure). Thence, this paper addresses experimental results for diagnosing faults with different rolling element bearing damage via motor current spectral analysis. Rolling element bearings generally consist of two rings, an inner and outer, between which a set of balls or rollers rotate in raceways. We set the experimental test bed to detect the rolling-element bearing misalignment of 3 type induction motors with normal condition bearing system, shaft deflection system by external force and a hole drilled through the outer race of the shaft end bearing of the four pole test motor. This paper takes the initial step of investigating the efficacy of current monitoring for bearing fault detection by incipient bearing failure. The failure modes are reviewed and the characteristics of bearing frequency associated with the physical construction of the bearings are defined. The effects on the stator current spectrum are described and related frequencies are also determined. This is an important result in the formulation of a fault detection scheme that monitors the stator currents. We utilized the FFT, Wavelet analysis and averaging signal pattern by inner product tool to analyze stator current components. The test results clearly illustrate that the stator signature can be used to identify the presence of a bearing fault.

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NDVI와 기온자료를 이용한 광역증발산량의 추정 (Estimation of Areal Evapotranspiration Using NDVI and Temperature Data)

  • 신사철;안태용
    • 한국지리정보학회지
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    • 제7권3호
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    • pp.79-89
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    • 2004
  • 원격탐사 기법은 식생 및 토지이용과 같은 지형조건과 관련된 증발산량을 산정하기 위한 하나의 수단으로 효과적으로 이용될 수 있다. 지표면에서 발생되는 증발산량을 지배하는 인자는 기온, 습도, 바람, 일사량 및 토양조건 둥 매우 복잡하게 구성된다. 식생은 그 지점의 증발산량에 영향을 주고 있으며, 증발산량을 지배하는 복잡한 인자는 식생의 성장조건에 직접적으로 영향을 미친다. 결국 증발산량과 식생조건 사이에는 강한 상관관계가 성립될 수 있음을 예상할 수 있다. 비교적 넓은 지점에 대한 식생상태를 파악을 위해서는 NOAA/AVHRR 자료가 효과적으로 이용될 수 있으며, 이로부터 얻어지는 식생지수(NDVI)를 이용함으로서 증발산량과 NDVI 사이의 강한 상관관계를 생각할 수 있다. 본 연구에서는 이러한 점을 근거로 하여 NDVI와 기상자료를 조합하는 간편한 방법에 의한 실제증발산량 산정방법을 제안한다.

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Delamination and concrete quality assessment of concrete bridge decks using a fully autonomous RABIT platform

  • Gucunski, Nenad;Kee, Seong-Hoon;La, Hung;Basily, Basily;Maher, Ali
    • Structural Monitoring and Maintenance
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    • 제2권1호
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    • pp.19-34
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    • 2015
  • One of the main causes of a limited use of nondestructive evaluation (NDE) technologies in bridge deck assessment is the speed of data collection and analysis. The paper describes development and implementation of the RABIT (Robotics Assisted Bridge Inspection Tool) for data collection using multiple NDE technologies. The system is designed to characterize three most common deterioration types in concrete bridge decks: rebar corrosion, delamination, and concrete degradation. It implements four NDE technologies: electrical resistivity (ER), impact echo (IE), ground-penetrating radar (GPR), and ultrasonic surface waves (USW) method. The technologies are used in a complementary way to enhance the interpretation. In addition, the system utilizes advanced vision to complement traditional visual inspection. Finally, the RABIT collects data at a significantly higher speed than it is done using traditional NDE equipment. The robotic system is complemented by an advanced data interpretation. The associated platform for the enhanced interpretation of condition assessment in concrete bridge decks utilizes data integration, fusion, and deterioration and defect visualization. This paper concentrates on the validation and field implementation of two NDE technologies. The first one is IE used in the delamination detection and characterization, while the second one is the USW method used in the assessment of concrete quality. The validation of performance of the two methods was conducted on a 9 m long and 3.6 m wide fabricated bridge structure with numerous artificial defects embedded in the deck.

CFD 해석을 적용한 18650 리튬-이온 배터리 팩의 열 해석 신뢰도 기초 분석 (Basic Investigation into the Validity of Thermal Analysis of 18650 Li-ion Battery Pack Using CFD Simulation)

  • 심창휘;김한상
    • 한국수소및신에너지학회논문집
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    • 제31권5호
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    • pp.489-497
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    • 2020
  • The Li-ion battery is considered to be one of the potential power sources for electric vehicles. In fact, the efficiency, reliability, and cycle life of Li-ion batteries are highly influenced by their thermal conditions. Therefore, a novel thermal management system is highly required to simultaneously achieve high performance and long life of the battery pack. Basically, thermal modeling is a key issue for the novel thermal management of Li-ion battery systems. In this paper, as a basic study for battery thermal modeling, temperature distributions inside the simple Li-ion battery pack (comprises of nine 18650 Li-ion batteries) under a 1C discharging condition were investigated using measurement and computational fluid dynamics (CFD) simulation approaches. The heat flux boundary conditions of battery cells for the CFD thermal analysis of battery pack were provided by the measurement of single battery cell temperature. The temperature distribution inside the battery pack were compared at six monitoring locations. Results show that the accurate estimation of heat flux at the surface of single cylindrical battery is paramount to the prediction of temperature distributions inside the Li-ion battery under various discharging conditions (C-rates). It is considered that the research approach for the estimation of temperature distribution used in this study can be used as a basic tool to understand the thermal behavior of Li-ion battery pack for the construction of effective battery thermal management systems.

분만 후 첫 번째 번식검진시 난소 및 자궁 질환에 따른 유성분 수준 비교 (The relationship between milk composition and conditions of ovary and uterus with reproductive fresh check in early lactating cows)

  • 문진산;신종봉;손창호;주이석;강현미;김종만
    • 대한수의학회지
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    • 제42권2호
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    • pp.163-170
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    • 2002
  • The relationship between level of milk composition and conditions of ovary and uterus were analyzed in Holstein cows at seven farms participating in a reproductive herd health management program. Milk data were taken from 503 early lactating cows between 30 and 60 days in milk with reproductive examination with ultrasonography from september 1999 to August 2000. Milk fat, protein and solid-not-fat concentration in the herds were $3.70{\pm}1.08%$, $2.97{\pm}0.35$, and $8.41{\pm}0.61%$, respectively. The reproductive disorder relative to normal cows had higher risk in the cows that the level of protein was lower than 2.70%. Also, the higher milk fat than 4.50% were associated with a higher risks in the uterine disease and follicular cysts. Therefore, the cows with the fat to protein ratio of > 1.30 had higher risks for reproductive disorder such as cystic ovarian diseases, inactive ovaries and endometritis. These results indicated that cows diagnosed with reproductive disorder were energy deficient prior to reproductive disorder diagnosis. Consequently, milk fat and protein analyses may be used serve as a monitoring tool for condition of ovary and uterus in early lactating cows

Impact of Prognostic Factors on Survival Rates in Patients with Ovarian Carcinoma

  • Arikan, Sevim Kalsen;Kasap, Burcu;Yetimalar, Hakan;Yildiz, Askin;Sakarya, Derya Kilic;Tatar, Sumeyra
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권15호
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    • pp.6087-6094
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    • 2014
  • Purpose: The aim of the present study was to invesitigate the impact of significant clinico-pathological prognostic factors on survival rates and to identify factors predictive of poor outcome in patients with ovarian carcinoma. Materials and Methods: A retrospective chart review of 74 women with pathologically proven ovarian carcinoma who were treated between January 2006 and April 2011 was performed. Patients were investigated with respect to survival to find the possible effects of age, gravida, parity, menstruel condition, pre-operative Ca-125, treatment period, cytologic washings, presence of ascites, tumor histology, stage and grade, maximal tumor diameter, adjuvan chemotherapy and cytoreductive success. Also 55 ovarian carcinoma patients were investigated with respect to prognostic factors for early 2-year survival. Results: The two-year survival rate was 69% and the 5-year survival rate was 25.5% for the whole study population. Significant factors for 2-year survival were preoperative CA-125 level, malignant cytology and FIGO clinical stage. Significant factors for 5-year survival were age, preoperative CA-125 level, residual tumor, lymph node metastases, histologic type of tumor, malignant cytology and FIGO clinical stage. Logistic regression revealed that independent prognostic factors of 5-year survival were patient age, lymph node metastasis and malignant cytology. Conclusions: We consider quality registries with prospectively collected data to be one important tool in monitoring treatment effects in population-based cancer research.

감기 환자와 건강대조군 간의 설 특성 비교연구 (Comparative Study of Tongue Color in Common Cold Patients and Controls)

  • 김지혜;주종천;박수정;김근호
    • 동의생리병리학회지
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    • 제30권5호
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    • pp.320-326
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    • 2016
  • Tongue diagnosis is convenient and non-invasive method to examine the body's functional condition, and it has been frequently used in traditional Korean Medicine (KM). The aim of this study was to investigate the difference of the tongue color assessed by computerized tongue image analysis system (CTIS) between the common cold (CC) patients and healthy subjects. A total of 85 participants, including 45 CC patients without organic diseases and 40 healthy subjects, were asked to complete the CC symptom questionnaire. A tongue image was acquired by using CTIS. Color differences in Commission Internationale de l'Eclairage (CIE) L*, a* and b* between the CC patient group and the control group were analyzes by using paired t-test analysis. The variable CIE b* of the tongue body was significantly lower in CC than that in controls (P=0.019). The variable CIE L* of the tongue coating was significantly higher in CC than that in controls (P=0.032). In CC, the color of the tongue body seems to be changed to intense red color. The color of the tongue coating seems to be changed to thick fur. The present study demonstrated that the CTIS can be used as a diagnostic and monitoring tool for the objective and standardized evaluation of common cold in clinics.