• Title/Summary/Keyword: Pre-inspection

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Feasibility of fully automated classification of whole slide images based on deep learning

  • Cho, Kyung-Ok;Lee, Sung Hak;Jang, Hyun-Jong
    • The Korean Journal of Physiology and Pharmacology
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    • v.24 no.1
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    • pp.89-99
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    • 2020
  • Although microscopic analysis of tissue slides has been the basis for disease diagnosis for decades, intra- and inter-observer variabilities remain issues to be resolved. The recent introduction of digital scanners has allowed for using deep learning in the analysis of tissue images because many whole slide images (WSIs) are accessible to researchers. In the present study, we investigated the possibility of a deep learning-based, fully automated, computer-aided diagnosis system with WSIs from a stomach adenocarcinoma dataset. Three different convolutional neural network architectures were tested to determine the better architecture for tissue classifier. Each network was trained to classify small tissue patches into normal or tumor. Based on the patch-level classification, tumor probability heatmaps can be overlaid on tissue images. We observed three different tissue patterns, including clear normal, clear tumor and ambiguous cases. We suggest that longer inspection time can be assigned to ambiguous cases compared to clear normal cases, increasing the accuracy and efficiency of histopathologic diagnosis by pre-evaluating the status of the WSIs. When the classifier was tested with completely different WSI dataset, the performance was not optimal because of the different tissue preparation quality. By including a small amount of data from the new dataset for training, the performance for the new dataset was much enhanced. These results indicated that WSI dataset should include tissues prepared from many different preparation conditions to construct a generalized tissue classifier. Thus, multi-national/multi-center dataset should be built for the application of deep learning in the real world medical practice.

Recycling of Safety Check Valves Contaminated with Radioactivity by Chemical Decontamination (化學除染에 의한 逆止밸브의 再使用)

  • 정종헌;최왕규;원휘준;심준보;오원진
    • Resources Recycling
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    • v.10 no.1
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    • pp.56-65
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    • 2001
  • Chemical decontamination techniques have been employed to reuse the high cost check valves contaminated with radioactivity and to reduce the radiation exposure during the inspection and maintenance work of safety injection system containing check valves. After chemical decontamination, an ultrasonic treatment was conducted to remove the fine solid particles retained in the crevices of check valves. The decontamination process conditions and the amount of chemical reagents were determined from the results of a pre-test, using the (list arm holder. The decontamination factors (DF), estimated from the activity in the solution, ranged from 14.5 to 18.5 corresponding to the activity removal of 93-95ft. The corrosion test data indicated that the general corrosion rate during a chemical decontamination-ultrasonic treatment process are low for type 304 S tainless steel, Inconel -600 and Stellite-6 materials $ (2.1\times10^{-2}$ $6.0\times10^{-2}$ and$ 1.7\times10^{-2}$ mil, respectively).

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Partial Discharge Position Tracking Method using a GIS Partial Discharge Signal and Arrival Time Difference (GIS 부분방전 신호와 도착 시간차 분석을 통한 PD발생 위치 추적)

  • Choi, Mun-Gyu;Cha, Hanju
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.9
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    • pp.1297-1301
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    • 2013
  • This paper analyzes of PD occurrence position through an analysis of the arrival time difference between the GIS partial discharge signal. Because of GIS (Gas Insulated Switchgear) is a facility very important power equipment and as part of the equipment that make up the power system, the stabilization of the power industry, which accounted for 88.5% share of GIS substation in the form of a substation is an important equipment for power supply. In the situation where we are gradually expanding the need for preventive diagnosis in order to improve the efficiency of equipment management and failure prevention for Preventive diagnosis. In this paper as a method for extracting pre-defect of failure of GIS Apply the average value method of calculating the 5 times each using a pulse of the first time of the second pulse (${\Delta}t$) with an oscilloscope generation position PD(Partial Discharge). the results of GIS internal inspection, the partial discharge of the actual the position of the partial discharge was confirmed with an accuracy of about 82% of positions. Arrival time difference in the most effective manner if the partial discharge of GIS internal occurs by applying the averaging method and TOA(Time of arrival) method, the partial discharge occurs you through the measurement and analysis of PD signal occurs was confirmed in the experiment are presented and diagnostic methods location tracking.

Evaluation of Fracture Toughness and Constraint Effect of Cruciform Specimen under Biaxial Loading (이축하중을 받는 십자형 시편의 파괴인성 및 구속효과 평가)

  • Kim, Jong Min;Kim, Min Chul;Lee, Bong Sang
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.12 no.1
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    • pp.62-69
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    • 2016
  • Current guidance considers that uniaxially loaded specimen with a deep crack is used for the determination of the ductile-to-brittle transition temperature. However, reactor pressure vessel is under biaxial loading in real and the existence of deep crack is not probable through periodic in-service-inspection. The elastic stress intensity factor and the elastic-plastic J-integral which were used for crack-tip stress field and fracture mechanics assessment parameters. The difference of the loading condition and crack geometry can significantly influence on these parameters. Thus, a constraint effect caused by differences between standard specimens and a real structure can over/underestimate the fracture toughness, and it affects the results of the structural integrity assessment, consequentially. The present paper investigates the constraint effects by evaluating the master curve $T_0$ reference temperature of PCVN (Pre-cracked Charpy V-Notch) and small scale cruciform specimens which was designed to simulate biaxial loading condition with shallow crack through the fracture toughness tests and 3-dimensional elastic-plastic finite element analyses. Based on the finite element analysis results, the fracture toughness values of a small scale cruciform specimen were estimated, and the geometry-dependent factors of the cruciform specimen considered in the present study were determined. Finally, the transferability of the test results of these specimens was discussed.

Evaluation on Structural Stiffness and Grouting Efficiency of Concrete Track using Elastic Wave Tests (탄성파 기법을 이용한 콘크리트궤도의 구조강성 및 충전상태 평가에 관한 연구)

  • Lee, Il-Wha;Joh, Sung-Ho;Jang, Seung-Yup
    • Journal of the Korean Society for Railway
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    • v.12 no.1
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    • pp.55-64
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    • 2009
  • Recently, concrete track is replacing ballast track for efficient and economic maintenance of track. It considerably offer less maintenance, a longer service life and reduced life-cycle costs. With the aim of achieving high-quality track construction work, of developing tools for quality assurance in new construction and for later technical inspection of material condition, a quality strategy has to be developed. For these purpose, NDT which is using the seismic wave has carried out in situ studies in the test construction section. The used NDT are SASW test, impact echo test and continuous impact echo test. The test is performed 5,353 times on 49 pre-cast concrete track panels to verify the stiffness structure and grouting efficiency of the track structure. To conclude, because of the non-homogeneous characteristic of concrete material. it is restricted to apply the elastic wave test at some aspect. However it is possible to acquisite a sufficient reliability about structural stiffness and grouting efficiency of concrete track.

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

  • Kim, Kui-Suk;Moon, Jeong-Suk;Kim, Yoon-Shin;Lee, Soo-Jin;Kim, Sang-Wook
    • Journal of the Korean Society of School Health
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    • v.16 no.1
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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.

Effects of Critical Pathway(CP) on the patients with Primary Total hip replacement(THR) (고관절 전치환술 환자의 Critical pathway적용효과)

  • Lee, Mi-Kyoung;Doh, Bok-Num
    • Journal of Korean Academy of Nursing Administration
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    • v.8 no.2
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    • pp.295-308
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    • 2002
  • Purpose: The purpose of this quasi-experimental research is to develop the CP for primary THR patients and verify its effectiveness. Method: The CP is designed for both patients and medical employees to meet the 14-day-long hospitalization with an expert and clinical validity test, and the standardized orders are also created. 21 eligible subjects for the control group(with common care plan) and 27 subjects for the experimental group(with CP service) were assigned. Data were collected from questionnaires to evaluate patients' satisfaction level of nursing care and CP, investigation of physical complications, inspection of LOS(length of hospital stay) and hospital charges from April 2000 to February 2001 at K-hospital in Daegu. The collected data were analyzed by using the SAS program. Results: After implementation of CP, there was a statistically significant reduction in mean length of stay. The hospital charges have no considerable difference between two groups. Frequency of physical complications is reduced considerably. The experimental group scored much higher than the control group on the satisfaction level toward nursing care. And in the analysis of CP satisfaction questionnaires, many subjects have high satisfaction in items of 'I see the treatment process and hospital life', 'I feel that I am participating in my treatment process with health care staff'. The analysis of variances which cause a prolonged LOS supports that it's necessary to strengthen an evaluation of pre-operative outpatients' condition and link the home nursing care system in discharge for more shortening of LOS. Conclusion: The above results show that CP can have a positive impact on satisfaction level of inpatients with primary THR and the hospital.

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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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    • v.14 no.1
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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.).

Comparison of Computational Thinking Improvement Based on Teaching Aids and Student's Level in Elementary Software Education (초등학교 소프트웨어교육에서 교구와 학습자 수준에 따른 컴퓨팅사고력 향상도 비교)

  • Lee, YoungJae;Kim, Yungsik
    • The Journal of Korean Association of Computer Education
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    • v.23 no.2
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    • pp.31-39
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    • 2020
  • As the importance of software education is emphasized, various educations for improve the computational thinking of elementary school students are being provided. However, there are many limitations that apply to the school at preceding studies. because they were invented for specific environment or students. Therefore, in this study, software education was conducted by constructing teaching-learning activities in consideration of the characteristics of students such as teaching aids and level of computational thinking ability, which can influence students based on the contents of textbooks. Through the comparison about computational thinking improvements, this study tried to suggest the direction of effective software education method. As a result, there are differences in computational thinking improvements according to the student's level and used teaching aids. Specifically, visual programming and unplugged type teaching-learning activities were more effective in teaching aids, and according to the level of students, students with low level of computing thinking in pre-inspection showed relatively high improvement. This tendency suggests that it is necessary to consider various learning factors in designing teaching-learning activities in elementary software education.

Direct shear testing of brittle material samples with non-persistent cracks

  • Haeri, Hadi;Sarfarazi, Vahab;Shemirani, Alireza Bagher;Zhu, Zheming
    • Geomechanics and Engineering
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    • v.15 no.4
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    • pp.927-935
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    • 2018
  • The mechanical behavior of the brittle material samples containing the internal and edge cracks are studied under direct shear tests. It is tried to investigate the effects of stress interactions and stress intensity factors at the tips of the pre-existing cracks on the failure mechanism of the bridge areas within these cracks. The direct shear tests are carried out on more than 30 various modeled samples each containing the internal cracks (S models) and edge cracks (E models). The visual inspection and a low power microscope are used to monitor the failure mechanisms of the tested samples. The cracks initiation, propagation and coalescences are being visualized in each test and the detected failure surfaces are used to study and measure the characteristics of each surface. These investigations show that as the ratio of the crack area to the total shear surface increases the shear failure mode changes to that of the tensile. When the bridge areas are fixed, the bridge areas in between the edge cracks have less strength than those of internal cracks. However, the results of this study show that for the case of internal cracks as the bridge area is increased, the strength of the material within the bridge area is decreased. It has been shown that the failure mechanism and fracture pattern of the samples depend on the bridge areas because as the bridge area decreases the interactions between the crack tip stress fields increases.