• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.6
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• pp.80-85
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• 2010

BGA 409 chip currently the most as a visual inspection of the exterior inspection is conducted. Human depending on visual inspection of the exterior inspection of the current state of testers, depending on how the test results because the change is difficult to expect reliable results. Therefore, the challenges of visual inspection of BGA solder balls to improve the visual inspection technique was developed. However, BGA solder ball size of the microstructure and the characteristics of the distinction between hard test the accuracy of the fall orientation error has a problem. In this paper BGA solder balls exterior inspection of the accuracy to improve the edge detection algorithm, the complement of features and only the comparison proposed a pattern-matching techniques, based on the characteristics of spatial configuration of the area by improving the standard error of the orientation proposed improvements.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.1
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• pp.81-87
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• 2012

This paper focuses on three-dimensional measurement system of micro balls on micro Ball-Grid-Array(BGA) packages in-line. Most of visual inspection system still suffers from sophisticate reflection characteristics of micro balls. For accurate shape measurement of them, a specially designed visual sensor system is proposed under the sensing principle of phase shifting moire interferometry. The system consists of a pattern projection system with four projection subsystems and an imaging system. In the projection system, four subsystems have spatially different projection directions to make target objects experience the pattern illuminations with different incident directions. For the phase shifting, each grating pattern of subsystem is regularly moved by PZT actuator. To remove specular noise and shadow area of BGA balls efficiently, a compact multiple-pattern projection and imaging system is implemented and tested. Especially, a sensor fusion algorithm to integrate four information sets, acquired from multiple projections, into one is proposed with the basis of Bayesian sensor fusion theory. To see how the proposed system works, a series of experiments is performed and the results are analyzed in detail.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.127-130
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• 2000

소형 모터의 제품검사에 있어서 인간의 청각에 의한 소음 및 이음 검사가 널리 관능검사에 의존하고 있지만 이는 판정기준의 객관성이 결여된다. 그래서 이를 대신하여 모터가 회전할 때 발생하는 음향신호에 의해 모터의 이상 유무의 판정에 대하여 기술하였다. 본 연구에서는 인간의 청각에 의한 관능검사에 의존도가 높은 자동차용 소형 DC 모터를 대상으로 이상음 검출을 위해 단구간 FFT의 시간이동 평균을 이용하여 음향신호를 해석하고 각 대역에서 추출된 파워를 비교하여 정상과 이상 모터의 판별이 뚜렷한 최적의 대역을 선택하고 이를 패턴 화하여 소형 DC 모터 이상유무 실시간 자동진단 시스템에 적용 하고자 한다.

• Annual Conference on Human and Language Technology
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• 2002.10e
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• pp.147-154
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• 2002

이 논문은 한국어 문서 교정을 위해 부산대학교 인공지능 연구실에서 개발되고 있는 맞춤법 및 문법 검사기와 그 지식베이스 구축에 대해 알아본다. 비대칭 관계(asymmetric relation) 설정과 더불어 개발된 문법 검사기는 한 문장의 임의의 두 요소간의 비대칭 관계를 토대로 (1) 잠재적 지배관계 개념을 설정하고 (2) 부분 문장 분석 방법을 사용한다. 이런 요소들을 효율적으로 운영하는 시스템을 구현하기 위해서는 한국어에 대한 이해와 경험적 자료를 적절히 조화시킨 지식베이스 구축이 필수적이다. 이 논문은 그 선수(先手) 작업으로 한국어 문서의 오류들을 관찰하고, 그로부터 추출한 언어적이거나 언어 외적인 요소들로부터 일반적 패턴을 뽑아내어 사용자의 기대를 만족시키기 위한 적절한 규칙지식베이스를 구축하고 문법 검사기의 성능 향상을 위해 문장 분석 출발점과 분석방향 그리고 분석범위를 한정한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.2
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• pp.313-318
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• 2012

This paper presents an automatic system to detect variety of faults from fine pitch COF(chip-on-film) which is less than $30{\mu}m$. Developed system contains circuits and technique to detect fast various faults such as hard open, hard short, soft open and soft short from fine pattern. Basic principle for fault detection is to monitor fine differential voltage from pattern resistance differences between fault-free and faulty cases. The technique uses also radio frequency resonator arrays for easy detection to amplify fine differential voltage. We anticipate that proposed system is to be an alternative for conventional COF test systems since it can fast and accurately detect variety of faults from fine pattern COF test process.

• The Journal of the Korea Contents Association
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• v.4 no.2
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• pp.50-60
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• 2004

Recently, most of the embedded system is required not only many functions but also real-time characteristics in purpose. In the hard real-time system, especially, strict deadline of periodic task can affect the performance of the system. In this paper, we design and implement the scheduler based on RM(Rate-Monotonic) rule. This scheduler makes feasible patterns based on EDF(Earliest deadline first) rule with extended schedulability inspection before execution, for periodic task-set that has high CPU utilization and then, execute periodic task-set depended on feasible patterns. The feasible pattern formed into EDF rule is capable of the efficiency of CPU up to 100 percentage and by the referenced execution of the feasible pattern is possible of removing the red-time scheduling overhead that is the defect of the order of dynamic assignment rule.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.347-354
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• 2014

Korea Central Cancer Registry reported in 2011 that the prevalence rate of thyroid cancer was about 19.6% (the highest) in both men and women. The ratio of thyroid cancer, among cancers that women suffer from, was about 31.1%, the highest among female cancers and about five times more than men. Regarding the incidence of thyroid cancer by age group, the crude rate was highest in women and men aged 15~34. From these figures it can be inferred that there is a greater relationship between thyroid cancer and hormones compared with other cancers. Therefore, young women aged 20~25, even if they are in full health, should undergo a medical examination. This study is aimed at examining changes in thyroid gland detected through self evaluation tests and the analysis of ultrasound screening images in persons aged 20~25. According to the study, 213 persons (about 46.6%) out of 457 people who took part in the study had abnormal echo patterns. With regard to women's abnormal patterns, about 73.4% of them were found to have calcified cystic, 11.8% diffuse-type low-echo and 7.3% cystic echo. With regard to male participants, about 61.1% were found to have calcified cystic, followed by 19.4% with the size of the isthmus increased and 13.9% with diffuse-type low-echo. According to the outcomes of an analysis regarding self-testing for hyperthyroidism, the average points of participants who were found to have abnormal echo patterns in ultrasound tests were 6.85 and the figure was 5.88 in persons with normal patterns. The figure was about 15% higher in abnormal respondents.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1347-1348
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• 2015

본 논문에서는 기상레이더 데이터에서 섞여있는 강수에코 및 비강수에코를 분류하기 위하여 Interval Type-2 FCM based RBFNN의 도움으로 사례 및 에코 분류기의 설계를 제안한다. 학습과 테스트 데이터는 현재 기상청에서 사용하는 UF radar data를 사용하였으며, 사례 분류기와 에코패턴 분류기의 데이터를 각각 생성한다. 전처리 과정인 사례 분류를 통하여 강수사례 혹은 비강수사례를 분류하여 강수사례일 경우 에코패턴분류를 진행하며, 비강수사례일 경우 데이터에 관측된 모든 반사도 값을 제거한다. 사례 및 에코 분류기는 Interval Type-2 FCM based RBFNN을 통하여 패턴분류를 진행하며, 패턴분류 성능을 확인한다. 또한 후반부 파라미터의 동정 시, 각 규칙에 파라미터를 전역적으로 구하는 LSE와 각 규칙에 대한 파라미터를 독립적으로 구하는 WSLE의 비교연구를 수행한다. 분류기의 성능을 확인하기 위하여 사례 분류 후 에코패턴분류의 결과는 현재 기상청에서 사용하고는 품질검사(QC) 데이터와 비교하여 평가하였다.

• Journal of the Korea Society of Computer and Information
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• v.18 no.11
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• pp.125-136
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• 2013

In this paper, we proposed SSL VPN-based network access control technology which can verify user authentication and integrity of user terminal. Using this technology, user can carry out a safety test to check security services such as security patch and virus vaccine for user authentication and user terminal, during the VPN-based access to an internal network. Moreover, this system protects a system from external security threats, by detecting malicious codes, based on behavioral patterns from user terminal's window API information, and comparing the similarity of sequential patterns to improve the reliability of detection.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.303-309
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• 2018

Computer vision technology is a component inspection to obtain a video image from the camera to the machine to perform the capabilities of the human eye with a field of artificial intelligence, and then analyzed by the algorithm to determine to determine the good and bad of production parts It is widely applied. Shape inspection method was used as how to identify the location of the start point and the end point of the search range, measure the height to the line scan method, in such a manner as to determine the presence or absence of the bolt tabs average brightness of the inspection area in a circular scan type value And the degree of similarity was calculated. The total time it takes to test in the test performance tests of two types of bolts tab enables test 300 min, and demonstrated the accuracy and efficiency of the inspection on the production line represented a complete inspection accuracy.