• 제목/요약/키워드: Inspection Period

검색결과 432건 처리시간 0.024초

이종금속 용접부 축방향 결함 검출을 위한 초음파 탐촉자 설계 (Ultrasonic Transducer Design for the Axial Flaw Detection of Dissimilar Metal Weld)

  • 윤병식;김용식;양승한
    • 비파괴검사학회지
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    • 제31권5호
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    • pp.536-542
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    • 2011
  • 원자력발전소의 이종금속 용접부는 PWSCC 결함에 민감한 것으로 알려져 있으며 기량검증된 검사자가 기량검증된 절차서를 사용하여 가동중검사 기간 중에 주기적인 검사를 수행하고 있다. 국내 원자력발전소 이종금속 용접부의 형상 조사 결과에 따르면 대부분의 이종금속 용접부가 경사진 노즐부나 인접부에 위치하는 것으로 나타났다. 일반적인 초음파 탐촉자를 사용하여 경사부위에 위치한 이종금속 용접부의 검사를 수행할 경우 초음파 탐촉자의 접근성이 제한되어 검사체적을 모두 검사하기가 어렵다. 특히 축방향 결함 검출을 위한 원주방향 주사에서는 초음파 탐촉자가 경사면에 위치하게 되면 반사체로부터 결함 신호를 얻기 가 어려우며 이에 따라 결함 검출이 어렵게 된다. 이러한 문제점을 극복하기 위해서는 경사면을 고려하여 비틀림 각도를 적용한 초음파 탐촉자를 사용하는 것이 필요하다. 모델링을 통하여 비틀림 굴절 종파탐촉자 를 설계하고 축방향 결함 검사용 비틀림 굴절 종파탐촉자를 제작하여 실험을 통하여 결함으로부터 신호를 취득하였다. 일반 탐촉자와 비틀림 각도가 적용된 탐촉자의 초음파 응답신호를 비교한 결과 비틀림 각도가 적용된 탐촉자의 초음파 응답신호가 훨씬 뛰어난 것으로 나타났다.

진단용 초음파 Probe 및 Mode 변화에 따른 초음파 주사빈도가 콩나물 발아 과정에 미치는 영향 (Effect of the Bean Sprouts Growth by Scanning Frequency of Diagnostic Ultrasound Probe Type and Mode Change)

  • 최관용;임현수
    • 대한의용생체공학회:의공학회지
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    • 제36권5호
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    • pp.150-154
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    • 2015
  • Long time ultrasound scan can cause a temperature rise in human tissue and affect the physical body. This is closely connected with patients' safety. So many researchers have been studied on this matter with animals such as mammals and experimental rat, because diagnostic ultrasound has been used many types of human organ to find disease. Therefore, this study is tested on bean sprouts to search how far the tissue temperature changes because of the excessive scanning consequence from ultrasound diagnosis and frequent number of ultrasonic scanning and how much affect their growth. The United States and several European countries have restrictions for number of scanning, while South Korea does not have any limitation for using ultrasound diagnosis. Comparison was that how different condition affect its' growing. The testing group is like many pregnancy moms to have 50 minutes in B-mode and color doppler mode by linear, convex and sector probe every day for a week and the other is to scan only once during the testing period. As a result, it was confirmed that there was a significant growing difference on frequent ultrasonic scanning group compared to normal one. So the final conclusion is that there needs to have a significant limitation of ultrasound scan time and a number of inspection when having for diagnostic ultrasound and recommendation like USA and a few European countries.

정비 데이터를 이용한 기만체계 신뢰도 분석 (Reliability Analysis for Decoy using Maintenance Data)

  • 곽혜림;홍석진;장민기
    • 한국산학기술학회논문지
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    • 제19권10호
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    • pp.82-88
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    • 2018
  • 방어용 무기체계 중 하나인 기만체계는 소모성 방식으로, One-shot system에 해당된다. 주기적 점검을 통해 신뢰도를 유지하며, 발사를 해보아야 정상 작동여부를 확인할 수 있어 고신뢰도가 요구된다. 본 논문에서 분석하고자 하는 기만체계는 개발 시 목표 신뢰도 설정 및 신뢰도 예측 없이 정비주기가 설정되었다. 그러나 현재 군에서 운용 중인 수량이 점점 증가하여 정비주기 최적화 필요성이 대두되었다. 이에 따라 수십 년간 지속적으로 운용된 기만체계의 정비 데이터를 통하여 신뢰도를 분석하고 최적 정비주기를 제시하였다. 2장에서 신뢰도 분석에 사용된 데이터 수집 및 분류방법을 제시하였으며, 분석 방법론에 대해 간략하게 소개하였다. 이를 토대로 3장에서 데이터에 대한 분포 분석 및 적합도 검증을 통해 본 기만체계 정비 데이터는 와이블 분포를 적용 하는 것이 가장 적합함을 확인하였으며, 와이블 분포의 형상 및 척도모수를 추정하였다. 4장에서는 도출된 분포를 통해 백분위수, 생존확률, MTBF 분석결과를 제시하였다. 또한 시간별 신뢰도 분석결과를 통해 적정 정비주기를 도출하였다. 5장 결론에서는 향후 본 연구결과에 대한 향후 활용방안을 제시하였다.

양식 넙치(Paralichthys olivaceus)에 대한 Erythromycin 휴약기간 설정 (Erythromycin Withdrawal Time in Olive Flounder (Paralichthys olivaceus) after Oral Administration)

  • 이태식;박미정;최혜승;심길보;박미선;신일식
    • 한국수산과학회지
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    • 제42권3호
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    • pp.204-208
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    • 2009
  • The withdrawal time of erythromycin in cultured olive flounder was investigated to ensure the food safety of the fish treated with erythromycin. The oral administration of erythromycin was carried out using the experimental diet containing erythromycin (200 mg/kg) daily dose of 40 mg/kg body weight. The 45 day experimental period was broken into 7 days of habituation, 8 days of medication and 30 days of additional feeding without antibiotics. The erythromycin concentration in the flounder muscle had been increased gradually with medication. After 5 days of medication, the concentration increased to its maximum level of 6.05 mg/kg. After discontinuing the antibiotic, the erythromycin concentration decreased drastically and day 9 was below 0.1 mg/kg. The erythromycin concentration had slowly declined from the 6th to the 20th day after medication and disappeared completely after 25 days. From these results, the time needed to reduce the erythromycin level to the 0.2 mg/kg limit adopted by the ED and Japan was suspected to be 4-6 days. Therefore, a reasonable withdrawal time following ED and Japanese regulatory guidelines for erythromycin in the cultured flounder could be estimated to be 10 days.

Other Gynecologic Pathology in Endometrial Cancer Patients

  • Khunnarong, Jakkapan;Tangjitgamol, Siriwan;Srijaipracharoen, Sunamchok
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권2호
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    • pp.713-717
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    • 2016
  • Background: To evaluate the prevalence and features of other gynecologic or surgical lesions in endometrial cancer (EMC) patients. Materials and Methods: Clinico-pathological data of EMC patients who were treated in the institution from 1995 to 2012 were collected. Data collected were age, stage of disease according to the FIGO 2009 criteria (FIGO), histopathology, tumor grade, adjuvant therapy, other gynecologic or surgical lesions, follow-up period, and living status. Results: The mean age of 396 patients was $56.7{\pm}10.64years$. Abnormal uterine bleeding was the most common presenting symptom (90.1%). Bleeding was accompanied with pelvic mass in 7.7% and 5.4% had only a pelvic mass. Abnormal cervical cytology was found in 3.8%. Approximately 75% had early stage diseases and 86% had endometrioid histology. We found 55.8% of EMC patients had other gynecologic lesions: 89.6% benign and 9.5% malignant. Some 4.5% had pre-invasive cervical/vulva/vagina lesions. The two most common gynecologic lesions were myoma uteri and ovarian tumors. Focusing on the latter, approximately 14% were benign while 8% were malignant. Among 364 patients with available data, surgical lesions were found in 11.8%, 5.7% benign and 9.2% malignant. The most common benign surgical condition was chronic appendicitis while breast and colon cancers were the two most common malignant lesions found. Conclusions: More than half of EMC patients had other gynecologic lesions including benign and malignant tumors. Surgical lesions were also found in more than one-tenth of patients. Careful pre-operative evaluation and intra-operative inspection are advised for proper management and better prognosis.

기계적 모터 고장진단을 위한 머신러닝 기법 (A Machine Learning Approach for Mechanical Motor Fault Diagnosis)

  • 정훈;김주원
    • 산업경영시스템학회지
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    • 제40권1호
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    • pp.57-64
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    • 2017
  • In order to reduce damages to major railroad components, which have the potential to cause interruptions to railroad services and safety accidents and to generate unnecessary maintenance costs, the development of rolling stock maintenance technology is switching from preventive maintenance based on the inspection period to predictive maintenance technology, led by advanced countries. Furthermore, to enhance trust in accordance with the speedup of system and reduce maintenances cost simultaneously, the demand for fault diagnosis and prognostic health management technology is increasing. The objective of this paper is to propose a highly reliable learning model using various machine learning algorithms that can be applied to critical rolling stock components. This paper presents a model for railway rolling stock component fault diagnosis and conducts a mechanical failure diagnosis of motor components by applying the machine learning technique in order to ensure efficient maintenance support along with a data preprocessing plan for component fault diagnosis. This paper first defines a failure diagnosis model for rolling stock components. Function-based algorithms ANFIS and SMO were used as machine learning techniques for generating the failure diagnosis model. Two tree-based algorithms, RadomForest and CART, were also employed. In order to evaluate the performance of the algorithms to be used for diagnosing failures in motors as a critical railroad component, an experiment was carried out on 2 data sets with different classes (includes 6 classes and 3 class levels). According to the results of the experiment, the random forest algorithm, a tree-based machine learning technique, showed the best performance.

학생체질검사제도에 대한 인식과 개선방안 연구 (A Study on the Improvement of Physical Examination for Students)

  • 김귀숙;문정숙;김윤신;이수진;김상욱
    • 한국학교보건학회지
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    • 제16권1호
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    • pp.37-54
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    • 2003
  • Recent domestic findings indicate steep increase of geriatric diseases such as obesity, diabetes, and high blood pressure among children and adolescents. It is, therefore, necessary to establish a new system for constitution inspection that reflects domestic adolescents' health conditions by the introduction of feasible items and systematic methods in the inspect ion. The objective of this study is to grasp the problems and to present proper ways of improving the system. As the method of the research during the period from September 2001 to March 2002 we refer to the domestic and foreign literature, and ask the advice of the specialists in pediatrics, family medicine, endocrine, cardiology. As on-site research we us e survey of nationwide elementary, middle, and high schools, visit representative local schools and have an interview with school nurses. Through the interview we try to find practical problems of school heath care and find proper method of students physic al examination. The abstract of the problems of student examination system is as following. To the question about the extent of the result of physical examination 46. 46.4%(school doctor) and 42.6%(parents and students) of the respondents answered "don't know". It means neglectfulness about examination itself. 62% of the school nurses responded "unsatisfactory" people who take charge of practical affairs have complaint about pre sent examination method. Because of the short time of the examination, and numerous students, the examination was incomplete. Several questions, method of physical examination, content of physical examination and list of physical examination, were raised. Reform measures for physical examination system of students were presented by physician, school nurses, students and parents of student.

REAL-TIME CORROSION CONTROL SYSTEM FOR CATHODIC PROTECTION OF BURIED PIPES FOR NUCLEAR POWER PLANT

  • Kim, Ki Tae;Kim, Hae Woong;Kim, Young Sik;Chang, Hyun Young;Lim, Bu Taek;Park, Heung Bae
    • Corrosion Science and Technology
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    • 제14권1호
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    • pp.12-18
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    • 2015
  • Since the operation period of nuclear power plants has increased, the degradation of buried pipes gradually increases and recently it seems to be one of the emerging issues. Maintenance on buried pipes needs high quality of management system because outer surface of buried pipe contacts the various soils but inner surface reacts with various electrolytes of fluid. In the USA, USNRC and EPRI have tried to manage the degradation of buried pipes. However, there is little knowledge about the inspection procedure, test and manage program in the domestic nuclear power plants. This paper focuses on the development and build-up of real-time monitoring and control system of buried pipes. Pipes to be tested are tape-coated carbon steel pipe for primary component cooling water system, asphalt-coated cast iron pipe for fire protection system, and pre-stressed concrete cylinder pipe for sea water cooling system. A control system for cathodic protection was installed on each test pipe which has been monitored and controlled. For the calculation of protection range and optimization, computer simulation was performed using COMSOL Multiphysics (Altsoft co.).

큐비즘(Cubism)이 활용된 현대 패션디자인의 조형적 특성 - 2010년 이후를 중심으로 - (The Formative Characteristics of Contemporary Fashion Design Adapting the Cubism - Focused on the Fashion since 2010 -)

  • 윤정아;이연희
    • 한국의상디자인학회지
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    • 제15권4호
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    • pp.209-221
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    • 2013
  • This study has attempted to investigate the effect of cubism on fashion and figure out how its formative characteristics have been expressed in contemporary fashion in the 21st century, focusing on the period since 2010. The propose of the study is to broaden research scope in fashion design through analysis and inspection on formative aspects among the cases which have proposed brand - new fashion designs by adapting cubism in fashion. To find out the characteristics of cubism in painting and formative characteristics of contemporary fashion in which the characteristics of cubism are reflected, a literature review has been conducted by referring to domestic and foreign books, previous papers, academic journals and Internet resources on cubism. For an empirical study, in addition, photos of cubism-applied modern fashion have been collected and analyzed through http://www. samsungdesign.net. The following results have been obtained: First, the formative characteristics of cubism were obtained in following categories; character of figure, simultaneity, reiteration and facticity. Second, according to analysis on cases after applying the formative characteristics on contemporary fashion design, the character of figure by the geometric shape of cubism was observed in fashion as well. After dismantling and reconfiguring garments, simultaneity has been expressed in an exaggerated and distorted manner through regular and repetitive overlapping or overlapping of irregular shapes. In terms of facticity, novelty has been delivered with the use of heterogeneous materials, using collage and patchwork techniques. Third, simplicity and functionality in cubism - style garments in the early 20th century have disappeared in contemporary design in the 21st century. Now, a dynamic aspect is only found. Fourth, unlike common paintings, 2D textiles are added to a 3D body in fashion design. In addition, it can be observed from multiple angles depending on the movement so that it can display more diverse shapes. Therefore, it could be the origin of inspiration to many designers.

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우리나라 식물검역 격리재배 시스템과 2005-2012년 실적보고 (Plant quarantine isolated cultivation system in Korea and results of recorded in 2005-2012)

  • 이시원;박정안;이오미;신용길
    • 농업과학연구
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    • 제40권4호
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    • pp.281-287
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    • 2013
  • 우리나라의 격리재배는 102속, 약 250여종의 식물에 대해 실시하고 있으며, 직접경검법, 배양법, 선택배지, 생리생화학, ELISA 및 PCR 검사방법을 사용한다. 2005-2012년, 우리나라에서 수행된 격리재배는 총 8,307건이며 이중 구근류가 5,165건(62.2%)로 가장 많았고, 묘목류가2,119건(25.0%), 종자 796건(9.6%), 삽수 150건(1.8%), 접수 70건(0.8%) 및 기타 7건(0.1%) 이었다. 불합격 사례는 총 413건으로 약 4.97%였고, 발견된 병의 종류는 총 47종으로 나타났다. 종류별로는 바이러스가 27종으로 가장 많은 수를 차지했으며, 곰팡이 16종, 바이로이드 1종, Chromalveolata 1종 및 기타 2종으로 나타났다. 가장 많은 검역건을 올린 병원체는 Arabis mosaic virus (77건), Tobacco rattle virus (70건), Lily symptomless virus (46건), Penicillium expansum (46건)이다.