• Title/Summary/Keyword: Pre-detection

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PCR Primer Developed for Diagnosis of Xanthomonas arboricola pv. pruni in Prune (자두 검은점무늬병원균의 PCR진단 및 검출)

  • Ryu, Young-Hyun;Lee, Joong-Hwan;Kwon, Tae-Young;Kim, Seung-Han;Kim, Dong-Geun
    • Research in Plant Disease
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    • v.16 no.2
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    • pp.125-128
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    • 2010
  • Bacterial black spot disease of prune fruit (Prunus salicina cv. formosa) has outbroke around major prune production area, Gimcheon, Euiseong and Gunwi in Gyungbuk province and has caused severe economic loss. Integrons PCR primer was designed along with sample pre-incubation and nested PCR method to enhance detection sensitivity for early detection of bacteria in fields. Designed integrons PCR primer successfully detected Xanthomonas arboricola pv. pruni from field collected samples, fruit, leaf, branch and even in raindrop collected from prune orchard. Pre-incubation along with nested PCR enhanced sensitivity to detect X. arboricola pv. pruni from seemingly healthy looking, symptomless branches. Designed integrons PCR can be used in prune nursery fields and in plant quarantine practice for the detection of X. arboricola pv. pruni.

Endpoint Detection Using Both By-product and Etchant Gas in Plasma Etching Process (플라즈마 식각공정 시 By-product와 Etchant gas를 이용한 식각 종료점 검출)

  • Kim, Dong-Il;Park, Young-Kook;Han, Seung-Soo
    • Journal of IKEEE
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    • v.19 no.4
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    • pp.541-547
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    • 2015
  • In current semiconductor manufacturing, as the feature size of integrated circuit (IC) devices continuously shrinks, detecting endpoint in plasma etching process is more difficult than before. For endpoint detection, various kinds of sensors are installed in semiconductor manufacturing equipments, and sensor data are gathered with predefined sampling rate. Generally, detecting endpoint is performed using OES data of by-product. In this study, OES data of both by-product and etchant gas are used to improve reliability of endpoint detection. For the OES data pre-processing, a combination of Signal to Noise Ratio (SNR) and Principal Component Analysis (PCA),are used. Polynomial Regression and Expanded Hidden Markov model (eHMM) technique are applied to pre-processed OES data to detect endpoint.

Damage detection for beam structures using an angle-between-string-and-horizon flexibility matrix

  • Yan, Guirong;Duan, Zhongdong;Ou, Jinping
    • Structural Engineering and Mechanics
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    • v.36 no.5
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    • pp.643-667
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    • 2010
  • The classical flexibility difference method detects damage by observing the difference of conventional deflection flexibility matrices between pre- and post-damaged states of a structure. This method is not able to identify multiple damage scenarios, and its criteria to identify damage depend upon the boundary conditions of structures. The key point behind the inability and dependence is revealed in this study. A more feasible flexibility for damage detection, the Angle-between-String-and-Horizon (ASH) flexibility, is proposed. The physical meaning of the new flexibility is given, and synthesis of the new flexibility matrix by modal frequencies and translational mode shapes is formulated. The damage indicators are extracted from the difference of ASH flexibility matrices between the pre- and post-damaged structures. One feature of the ASH flexibility is that the components in the ASH flexibility matrix are associated with elements instead of Nodes or DOFs. Therefore, the damage indicators based on the ASH flexibility are mapped to structural elements directly, and thus they can pinpoint the damaged elements, which is appealing to damage detection for complex structures. In addition, the change in the ASH flexibility caused by damage is not affected by boundary conditions, which simplifies the criteria to identify damage. Moreover, the proposed method can determine relatively the damage severity. Because the proposed damage indicator of an element mainly reflects the deflection change within the element itself, which significantly reduces the influence of the damage in one element on the damage indicators of other damaged elements, the proposed method can identify multiple damage locations. The viability of the proposed approach has been demonstrated by numerical examples and experimental tests on a cantilever beam and a simply supported beam.

Improvement of Mass Spectral Detection Performance by Pre-correction of Peak Position Error (피크위치오차 사전 보정을 통한 질량 스펙트럼 검출 성능 개선)

  • Lee, Young Hawk;Heo, Gyeongyong;Choi, Hun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.6
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    • pp.666-674
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    • 2019
  • In the mass spectrum of the mass spectrometer, the spectrum of the low peak adjacent to the spectrum having the high peak value is connected to each other and thus the separation is difficult. This inter-spectral overlap causes degradation of the mass spectral detection performance and resolution. In this paper, we propose a method to improve the mass spectrum detection performance and peak accuracy of residual gas analyzer. The type discrimination according to the characteristics of the ion signal block and the pre-correction for the peak position error can separate and detect the spectrum of the low peak connected to the adjacent spectra. To verify the performance of the proposed method, we compared the proposed method with the conventional method in simulations using actual ion signals obtained from the mass spectrometer under development.

DETECTION OF FRUITS ON NATURAL BACKGROUND

  • Limsiroratana, Somchai;Ikeda, Yoshio;Morio, Yoshinari
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.279-286
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    • 2000
  • The objective of this research is to detect the papaya fruits on tree in an orchard. The detection of papaya on natural background is difficult because colors of fruits and background such as leaves are similarly green. We cannot separate it from leaves by color information. Therefore, this research will use shape information instead. First, we detect an interested object by detecting its boundary using edge detection technique. However, the edge detection will detect every objects boundary in the image. Therefore, shape description technique will be used to describe which one is the interested object boundary. The good shape description should be invariant in scaling, rotating, and translating. The successful concept is to use Fourier series, which is called "Fourier Descriptors". Elliptic Fourier Descriptors can completely represent any shape, which is selected to describe the shape of papaya. From the edge detection image, it takes a long time to match every boundary directly. The pre-processing task will reduce non-papaya edge to speed up matching time. The deformable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.

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A Study on Realtime Drone Object Detection Using On-board Deep Learning (온-보드에서의 딥러닝을 활용한 드론의 실시간 객체 인식 연구)

  • Lee, Jang-Woo;Kim, Joo-Young;Kim, Jae-Kyung;Kwon, Cheol-Hee
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.10
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    • pp.883-892
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    • 2021
  • This paper provides a process for developing deep learning-based aerial object detection models that can run in realtime on onboard. To improve object detection performance, we pre-process and augment the training data in the training stage. In addition, we perform transfer learning and apply a weighted cross-entropy method to reduce the variations of detection performance for each class. To improve the inference speed, we have generated inference acceleration engines with quantization. Then, we analyze the real-time performance and detection performance on custom aerial image dataset to verify generalization.

A Study on Improving the Accuracy of Wafer Align Mark Center Detection Using Variable Thresholds (가변 Threshold를 이용한 Wafer Align Mark 중점 검출 정밀도 향상 연구)

  • Hyeon Gyu Kim;Hak Jun Lee;Jaehyun Park
    • Journal of the Semiconductor & Display Technology
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    • v.22 no.4
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    • pp.108-112
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    • 2023
  • Precision manufacturing technology is rapidly developing due to the extreme miniaturization of semiconductor processes to comply with Moore's Law. Accurate and precise alignment, which is one of the key elements of the semiconductor pre-process and post-process, is very important in the semiconductor process. The center detection of wafer align marks plays a key role in improving yield by reducing defects and research on accurate detection methods for this is necessary. Methods for accurate alignment using traditional image sensors can cause problems due to changes in image brightness and noise. To solve this problem, engineers must go directly into the line and perform maintenance work. This paper emphasizes that the development of AI technology can provide innovative solutions in the semiconductor process as high-resolution image and image processing technology also develops. This study proposes a new wafer center detection method through variable thresholding. And this study introduces a method for detecting the center that is less sensitive to the brightness of LEDs by utilizing a high-performance object detection model such as YOLOv8 without relying on existing algorithms. Through this, we aim to enable precise wafer focus detection using artificial intelligence.

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Automatic Detection of Dead Trees Based on Lightweight YOLOv4 and UAV Imagery

  • Yuanhang Jin;Maolin Xu;Jiayuan Zheng
    • Journal of Information Processing Systems
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    • v.19 no.5
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    • pp.614-630
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    • 2023
  • Dead trees significantly impact forest production and the ecological environment and pose constraints to the sustainable development of forests. A lightweight YOLOv4 dead tree detection algorithm based on unmanned aerial vehicle images is proposed to address current limitations in dead tree detection that rely mainly on inefficient, unsafe and easy-to-miss manual inspections. An improved logarithmic transformation method was developed in data pre-processing to display tree features in the shadows. For the model structure, the original CSPDarkNet-53 backbone feature extraction network was replaced by MobileNetV3. Some of the standard convolutional blocks in the original extraction network were replaced by depthwise separable convolution blocks. The new ReLU6 activation function replaced the original LeakyReLU activation function to make the network more robust for low-precision computations. The K-means++ clustering method was also integrated to generate anchor boxes that are more suitable for the dataset. The experimental results show that the improved algorithm achieved an accuracy of 97.33%, higher than other methods. The detection speed of the proposed approach is higher than that of YOLOv4, improving the efficiency and accuracy of the detection process.

Recognize Handwritten Urdu Script Using Kohenen Som Algorithm

  • Khan, Yunus;Nagar, Chetan
    • International Journal of Ocean System Engineering
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    • v.2 no.1
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    • pp.57-61
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    • 2012
  • In this paper we use the Kohonen neural network based Self Organizing Map (SOM) algorithm for Urdu Character Recognition. Kohenen NN have more efficient in terms of performance as compare to other approaches. Classification is used to recognize hand written Urdu character. The number of possible unknown character is reducing by pre-classification with respect to subset of the total character set. So the proposed algorithm is attempt to group similar character. Members of pre-classified group are further analyzed using a statistical classifier for final recognition. A recognition rate of around 79.9% was achieved for the first choice and more than 98.5% for the top three choices. The result of this paper shows that the proposed Kohonen SOM algorithm yields promising output and feasible with other existing techniques.

Boosting Multifactor Dimensionality Reduction Using Pre-evaluation

  • Hong, Yingfu;Lee, Sangbum;Oh, Sejong
    • ETRI Journal
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    • v.38 no.1
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    • pp.206-215
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    • 2016
  • The detection of gene-gene interactions during genetic studies of common human diseases is important, and the technique of multifactor dimensionality reduction (MDR) has been widely applied to this end. However, this technique is not free from the "curse of dimensionality" -that is, it works well for two- or three-way interactions but requires a long execution time and extensive computing resources to detect, for example, a 10-way interaction. Here, we propose a boosting method to reduce MDR execution time. With the use of pre-evaluation measurements, gene sets with low levels of interaction can be removed prior to the application of MDR. Thus, the problem space is decreased and considerable time can be saved in the execution of MDR.