• Title/Summary/Keyword: Global weights

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A Light Exposure Correction Algorithm Using Binary Image Segmentation and Adaptive Fusion Weights (이진화 영상분할기법과 적응적 융합 가중치를 이용한 광노출 보정기법)

  • Han, Kyu-Phil
    • Journal of Korea Multimedia Society
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    • v.24 no.11
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    • pp.1461-1471
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    • 2021
  • This paper presents a light exposure correction algorithm for less pleasant images, acquired with a light metering failure. Since conventional tone mapping and gamma correction methods adopt a function mapping with the same range of input and output, the results are pleasurable for almost symmetric distributions to their intensity average. However, their corrections gave insufficient outputs for asymmetric cases at either bright or dark regions. Also, histogram modification approaches show good results on varied pattern images, but these generate unintentional noises at flat regions because of the compulsive shift of the intensity distribution. Therefore, in order to sufficient corrections for both bright and dark areas, the proposed algorithm calculates the gamma coefficients using primary parameters extracted from the global distribution. And the fusion weights are adaptively determined with complementary parameters, considering the classification information of a binary segmentation. As the result, the proposed algorithm can obtain a good output about both the symmetric and the asymmetric distribution images even with severe exposure values.

Isolation and Characterization of Two Korean Mistletoe Lectins

  • Kang, Tae-Bong;Song, Seong-Kyu;Yoon, Taek-Joon;Yoo, Yung-Choon;Lee, Kwan-Hee;Her, Erk;Kim, Jong-Bae
    • BMB Reports
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    • v.40 no.6
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    • pp.959-965
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    • 2007
  • Two isolectins (KML-IIU and the KML-IIL) were individually isolated from the previously reported Korean mistletoe lectin, KML-C, by using an immunoaffinity column. Molecular weights of the KML-IIU and the KML-IIL were 64 kDa and 60 kDa respectively. Both of the lectins were composed of heterogeneous A and B subunits linked with a disulfide bond, and showed the same carbohydrate-binding specificities for Gal and GalNAc. However, they are different not only in biophysical properties (glycosylation and amino acid compositions) but also bioactivities (cell killing and cytokine induction). The KML-IIL showed 17-145 times stronger in cytotoxicities to various human and mouse cancer cell lines than the KML-IIU. The KML-IIL also induced TNF-$\alpha$ secretion from mouse peritoneal macrophages 4.5 times better than the KML-IIU. The results demonstrated isolectins in Korean mistletoe were varied in bioactivities and the KML-IIL may be developed as an anti-cancer agent.

Local-step Optimization in Online Update Learning of Multilayer Perceptrons (다충신경망을 위한 온라인방식 학습의 개별학습단계 최적화 방법)

  • Tae-Seung, Lee;Ho-Jin, Choi
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10b
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    • pp.700-702
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    • 2004
  • A local-step optimization method is proposed to supplement the global-step optimization methods which adopt online update mode of internal weights and error energy as stop criterion in learning of multilayer perceptrons (MLPs). This optimization method is applied to the standard online error backpropagation(EBP) and the performance is evaluated for a speaker verification system.

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Leave-one-out Bayesian model averaging for probabilistic ensemble forecasting

  • Kim, Yongdai;Kim, Woosung;Ohn, Ilsang;Kim, Young-Oh
    • Communications for Statistical Applications and Methods
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    • v.24 no.1
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    • pp.67-80
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    • 2017
  • Over the last few decades, ensemble forecasts based on global climate models have become an important part of climate forecast due to the ability to reduce uncertainty in prediction. Moreover in ensemble forecast, assessing the prediction uncertainty is as important as estimating the optimal weights, and this is achieved through a probabilistic forecast which is based on the predictive distribution of future climate. The Bayesian model averaging has received much attention as a tool of probabilistic forecasting due to its simplicity and superior prediction. In this paper, we propose a new Bayesian model averaging method for probabilistic ensemble forecasting. The proposed method combines a deterministic ensemble forecast based on a multivariate regression approach with Bayesian model averaging. We demonstrate that the proposed method is better in prediction than the standard Bayesian model averaging approach by analyzing monthly average precipitations and temperatures for ten cities in Korea.

Strengthening sequence based on relative weightage of members in global damage for gravity load designed buildings

  • Niharika Talyan;Pradeep K. Ramancharla
    • Earthquakes and Structures
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    • v.26 no.2
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    • pp.131-147
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    • 2024
  • Damage caused by an earthquake depends on not just the intensity of an earthquake but also the region-specific construction practices. Past earthquakes in Asian countries have highlighted inadequate construction practices, which caused huge life and property losses, indicating the severe need to strengthen existing structures. Strengthening activities shall be proposed as per the proposed weighting factors, first at the higher weighted members to increase the capacity of the building immediately and thereafter, the other members. Through this study on gravity load-designed (GLD) buildings, relative weights are assigned to each storey and exterior and interior columns within a storey based on their contribution to the energy dissipation capacity of the building. The numerical study is conducted on mid-rise archetype GLD buildings, i.e., 4, 6, 8, and 10 stories with variable storey heights, in the high seismic zones. Non-linear static analysis is performed to compute weights based on energy dissipation capacities. The results obtained are verified with the non-linear time history analysis of 4 GLD buildings. It was observed that exterior columns have higher weightage in the energy dissipation capacity of the building than interior columns up to a certain building height. The damage in stories is distributed in a convex to concave parabolic shape from bottom to top as building height increases, and the maxima location of the parabola shifts from bottom to middle stories. Relative weighting factors are assigned as per the damage contribution. And the sequence for strengthening activities is proposed as per the computed weighting factors in descending order for regular RCC buildings. Therefore, proposals made in the study would increase the efficacy of strengthening activities.

Research on Technopark Management Performance Comparison Based on National Quality Awards Appraisal Standard by Countries (국가별 국가품질상 평가기준에 따른 테크노파크 경영실적 비교 연구)

  • Hwang, Sung-Taek;Park, Jong-Woo
    • Journal of Korean Society for Quality Management
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    • v.40 no.4
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    • pp.497-512
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    • 2012
  • Purpose: Most major countries have their own set of qualifications called national quality awards to measure the quality of companies and organizations. This study analyzes 3 different national quality awards and compare with the result from Korean quality awards conducted by Ministry of knowledge and Economy and Korea institute for advancement of technology. Methods: We tested 17 technoparks out of 18 technoparks in Korea and see how different the results can be depends on the value weights. We closely looked at each qualifications and tables of different countries' awards and compared with one used in Korea. Finally we proposed some suggestions to use not only domestic model but also international ones to be objective and add efficiency to organizations. Results: Depend on similarity of qualifications and weights, there were countries with different results and these caused score and ranking changes. Nevertheless, there was a comparison that did not make any changes on both score and ranking. Conclusion: We recognized the limitation that a standardized quality variation cannot be enough sources to test and analyze technoparks with different size and criteria. Integrating global standards and flow would be the first step to help grow technoparks and organizations placed in Korea in days to come.

Arsenic Toxicity in Male Reproduction and Development

  • Kim, Yoon-Jae;Kim, Jong-Min
    • Development and Reproduction
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    • v.19 no.4
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    • pp.167-180
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    • 2015
  • Arsenic is a toxic metalloid that exists ubiquitously in the environment, and affects global health problems due to its carcinogenicity. In most populations, the main source of arsenic exposure is the drinking water. In drinking water, chronic exposure to arsenic is associated with increased risks of various cancers including those of skin, lung, bladder, and liver, as well as numerous other non-cancer diseases including gastrointestinal and cardiovascular diseases, diabetes, and neurologic and cognitive problems. Recent emerging evidences suggest that arsenic exposure affects the reproductive and developmental toxicity. Prenatal exposure to inorganic arsenic causes adverse pregnancy outcomes and children's health problems. Some epidemiological studies have reported that arsenic exposure induces premature delivery, spontaneous abortion, and stillbirth. In animal studies, inorganic arsenic also causes fetal malformation, growth retardation, and fetal death. These toxic effects depend on dose, route and gestation periods of arsenic exposure. In males, inorganic arsenic causes reproductive dysfunctions including reductions of the testis weights, accessory sex organs weights, and epididymal sperm counts. In addition, inorganic arsenic exposure also induces alterations of spermatogenesis, reductions of testosterone and gonadotrophins, and disruptions of steroidogenesis. However, the reproductive and developmental problems following arsenic exposure are poorly understood, and the molecular mechanism of arsenic-induced reproductive toxicity remains unclear. Thus, we further investigated several possible mechanisms underlying arsenic-induced reproductive toxicity.

Image Retrieval using Adaptable Weighting Scheme on Relevance Feedback (사용자 피드백 기반의 적응적 가중치를 이용한 정지영상 검색)

  • 이진수;김현준;윤경로;이희연
    • Journal of Broadcast Engineering
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    • v.5 no.1
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    • pp.61-67
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    • 2000
  • Generally, relevance, feedback reflecting user's intention has been used to refine the refine the query conditions in image retrieval. However, in this paper, the usage of the relevance feedback is extended to the image database categorization so as to be accommodated to the user independent image retrieval. In our approach, to guarantee a desirable user-satisfactory performance descriptors and the elements of the descriptors corresponding unique features associatiated with of each image are weighted using the relevance feedback where experts can more lead rather than beginners do. In this paper, we propose a proper image description scheme consisting of global information, local information, descriptor weights and element weights based on color and texture descriptors. In addition, we also introduce an appropriate learning method based on the reliability scheme preventing wrong learning from abusive feedback.

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Measuring COVID-19 Effects on World and National Stock Market Returns

  • KHANTHAVIT, Anya
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.2
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    • pp.1-13
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    • 2021
  • Previous studies have found the significant adverse effects of coronavirus disease 2019 (COVID-19) on stock returns and volatility. The effects varied with the confirmed cases and deaths. However, the extent of the effects have never been measured exactly. This study proposes a measurement model for the COVID-19 effects. In the proposed model, stock returns in the COVID-19 period are weighted averages of pre-COVID-19 normal returns and COVID-19-induced returns. The effects are measured by the contributing weights of the COVID-19-induced returns. Kalman filtering is used to estimate the model for the world and Chinese markets, in combination with 10 markets - five most affected countries (United States, India, Brazil, Russia, and France) and five best recovering countries (Hong Kong, Australia, Singapore, Thailand, and South Korea). The sample returns are daily, obtained from the closing Morgan Stanley global investable market indexes. The full period is from September 24, 2018, to October 30, 2020, whereas the COVID-19 period is from November 18, 2019, to October 30, 2020. The contributing weights are significant and close to 100% for all markets. The COVID-19-induced returns replace the pre-COVID-19 normal returns; they are negatively auto-correlated and highly volatile. The COVID-19-induced returns are new normal returns in the COVID-19 period.

MALICIOUS URL RECOGNITION AND DETECTION USING ATTENTION-BASED CNN-LSTM

  • Peng, Yongfang;Tian, Shengwei;Yu, Long;Lv, Yalong;Wang, Ruijin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.11
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    • pp.5580-5593
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    • 2019
  • A malicious Uniform Resource Locator (URL) recognition and detection method based on the combination of Attention mechanism with Convolutional Neural Network and Long Short-Term Memory Network (Attention-Based CNN-LSTM), is proposed. Firstly, the WHOIS check method is used to extract and filter features, including the URL texture information, the URL string statistical information of attributes and the WHOIS information, and the features are subsequently encoded and pre-processed followed by inputting them to the constructed Convolutional Neural Network (CNN) convolution layer to extract local features. Secondly, in accordance with the weights from the Attention mechanism, the generated local features are input into the Long-Short Term Memory (LSTM) model, and subsequently pooled to calculate the global features of the URLs. Finally, the URLs are detected and classified by the SoftMax function using global features. The results demonstrate that compared with the existing methods, the Attention-based CNN-LSTM mechanism has higher accuracy for malicious URL detection.