• Title/Summary/Keyword: loss functions

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Soil sealing in the European Union (긴급제언 - 유럽연합의 토양포장)

  • Lee, Yeong Heui
    • Journal of the Korean Professional Engineers Association
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    • v.45 no.6
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    • pp.37-43
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    • 2012
  • Every year in Europe, soils covering an area larger than the city of Berlin are lost to urban sprawl and transport infrastructure. Soil sealing causes an irreversible loss of the biological functions of soil. As water can neither infiltrate nor evaporate, water runoff increases, sometimes leading to catastrophic floods. Landscapes are fragmented and habitats become too small or too isolated to support certain species. In addition, the food production potential of land is lost forever. There is an urgent need to use this valuable resource more wisely, in order to secure its many vital services for future generations. The EU faces new territorial challenges.

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Optimal Selection of Populations for Units in a System

  • Kim, Woo-Chul
    • Journal of the Korean Statistical Society
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    • v.9 no.2
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    • pp.135-144
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    • 1980
  • A problem of choosing units for the series system and the 1-out-of-2 system from k available brands is treated from a decision-theoretic points of view. It is assumed that units from each brand have exponentially distributed life lengths, and that the loss functions are inversely proportional to the reliability of the system. For the series system the 'natural' rule is shown to be optimal. For the 1-out-of-2 system, the Bayes rule wrt the natural conjugate prior is derived and teh constants to implement the Bayes rule are given.

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Mobile application for preventing card loss using the NFC technology (NFC 기술을 이용한 카드 분실을 방지하기 위한 모바일 앱)

  • Kang, Ki-Beom;Jwa, Jeong-Woo;Kim, Soon-Whan;Kim, Heung-Soo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.1
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    • pp.181-188
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    • 2017
  • As smart phone users increase the number of users who insert credit cards into wallet type smart phone cases is increasing. In this paper, we developed an Android application for preventing credit card loss in a wallet type smart phone case using the NFC (Near Field Communication) technology of smart phone. The developed android application uses the NFC reading and writing functions of the smart phone. When the credit card is inserted into the wallet type smart phone case, the android application detects the NFC tag in the credit card and registers credit card information. When the credit card is removed from the smart phone case, the Android application automatically detects the credit card loss and notifies to the user. The user can check and finds the location information of the lost credit card on the map of the Android application. We can easily develop the Android application for preventing credit card loss when a function that automatically detects an leaving NFC tag is added to Android.

Early potential effects of resveratrol supplementation on skeletal muscle adaptation involved in exercise-induced weight loss in obese mice

  • Sun, Jingyu;Zhang, Chen;Kim, MinJeong;Su, Yajuan;Qin, Lili;Dong, Jingmei;Zhou, Yunhe;Ding, Shuzhe
    • BMB Reports
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    • v.51 no.4
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    • pp.200-205
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    • 2018
  • Exercise and resveratrol supplementation exhibit anti-obesity functions in the long term but have not been fully investigated yet in terms of their early potential effectiveness. Mice fed with high-fat diet were categorized into control (Cont), exercise (Ex), resveratrol supplementation (Res), and exercise combined with resveratrol supplementation (Ex + Res) groups. In the four-week period of weight loss, exercise combined with resveratrol supplementation exerted no additional effects on body weight loss but significantly improved whole-body glucose and lipid homeostasis. The combined treatment significantly decreased intrahepatic lipid content but did not affect intramyocellular lipid content. Moreover, the treatment significantly increased the contents of mtDNA and cytochrome c, the expression levels of peroxisome proliferator-activated receptor gamma coactivator-1 alpha and its downstream transcription factors, and the activities of ATPase and citrate synthase. However, exercise, resveratrol, and their combination did not promote myofiber specification toward slow-twitch type. The effects of exercise combined with resveratrol supplementation on weight loss could be partly due to enhanced mitochondrial biogenesis and not to fiber-type shift in skeletal muscle tissues.

Determination of Optimal Unit Hydrographs and Infiltration Rate Functions at the site of the Su-Jik Bridge in the HwangGuJichen River (황구지천 수직교 지점에서의 최적 단위도 및 침투율의 결정)

  • Ahn, Taejin;Cho, Byung Doon;Lyu, Heui Jeong
    • Journal of Wetlands Research
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    • v.7 no.3
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    • pp.57-66
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    • 2005
  • This paper is to present the determination of the optimal loss rate parameters and unit hydrographs from the observed single rainfall-runoff event using optimization model. The linear program models has been formulated to derive the optimal unit hydrographs and loss rate parameters for the site of the Su-Jik Bridge in the HwangGuJichen River; one minimizes the summation of the absolute residual between predicted and observed runoff ordinates. In the perturbation stage of parameters the trial and error method has been adopted to determine the loss rate parameters for Kostiakov's, Philip's, Horton's, and Green-Ampt's equation. The unique unit hydrograph ordinates for a given rainfall-runoff event is exclusively obtained with ${\Phi}$ index, but unit hydrograph ordinates depend upon the parameters for each loss rate equations. In this paper the single rainfall-runoff event observed from the sample watershed is considered to test the proposed method. The optimal unit hydrograph obtained by the optimization model has smaller deviations than the ones by the conventional method.

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Deep learning-based monitoring for conservation and management of coastal dune vegetation (해안사구 식생의 보전 및 관리를 위한 딥러닝 기반 모니터링)

  • Kim, Dong-woo;Gu, Ja-woon;Hong, Ye-ji;Kim, Se-Min;Son, Seung-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.25 no.6
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    • pp.25-33
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    • 2022
  • In this study, a monitoring method using high-resolution images acquired by unmanned aerial vehicles and deep learning algorithms was proposed for the management of the Sinduri coastal sand dunes. Class classification was done using U-net, a semantic division method. The classification target classified 3 types of sand dune vegetation into 4 classes, and the model was trained and tested with a total of 320 training images and 48 test images. Ignored label was applied to improve the performance of the model, and then evaluated by applying two loss functions, CE Loss and BCE Loss. As a result of the evaluation, when CE Loss was applied, the value of mIoU for each class was the highest, but it can be judged that the performance of BCE Loss is better considering the time efficiency consumed in learning. It is meaningful as a pilot application of unmanned aerial vehicles and deep learning as a method to monitor and manage sand dune vegetation. The possibility of using the deep learning image analysis technology to monitor sand dune vegetation has been confirmed, and it is expected that the proposed method can be used not only in sand dune vegetation but also in various fields such as forests and grasslands.

Review of No Net Loss(NLL) of Wetland and Suggestion of Appropriate NLL in Korea (내륙습지 총량관리제도의 고찰 및 도입 방안 제안)

  • Yujin Kang;Junhyeong Lee;Taewoo Lee;Duckgil Kim;Jaeseung Seo;Soojun Kim;Hung Soo Kim
    • Journal of Wetlands Research
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    • v.26 no.3
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    • pp.227-235
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    • 2024
  • Inland wetlands provide important ecosystem services or functions, including biodiversity conservation, water purification, flood control, and carbon sequestration. However, many inland wetlands are being degraded by urbanization and industrialization, raising the need for conservation and restoration. This study proposes the adoption of No Net Loss(NLL) of Wetland for wetland conservation and restoration in Korea by the review of the literatures. To this end,, we analyzed the wetland conservation and management systems of the United States, Canada, Germany, Japan, and Australia, and identified institutional features and success factors of each country, and sought ways to adapt them to domestic conditions of Korea. The case of the United States highlights the importance of legal frameworks and public-private collaboration, Canada demonstrates systematic management approaches, Germany maintains a balance between development and conservation, Japan underscores the need for cooperative conservation efforts, and Australia emphasizes the efficiency of offset markets. The introduction and operation of these schemes are expected to contribute to climate change mitigation, biodiversity conservation, and water quality improvement, but ongoing research and policy efforts are needed to ensure that the schemes are well established.

Depletion of Cytoplasmic Tail of UL18 Enhances and Stabilizes the Surface Expression of UL18

  • Kim, Jung-Sik;Kim, Bon-Gi;Yoon, Il-Hee;Kim, Sang-Joon;Park, Chung-Gyu
    • IMMUNE NETWORK
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    • v.8 no.4
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    • pp.130-136
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    • 2008
  • Background: Human cytomegalovirus UL18, a MHC class I homologue, has been considered a natural killer (NK) cell decoy. It ligates LIR-1/ILT2 (CD85j), an NK inhibitory receptor, to prevent lysis of infected target cells. However, precise role of UL18 to NK cell cytotoxicity is yet elusive. Difficulty in clarifying the function of UL18 lies in complication in detecting UL18 mainly due to low level expression of UL18 on the surface and gradual loss of its expression. Methods: To overcome this hurdle, cDNA of cytoplasmic tail-less UL18 was constructed and expressed in swine endothelial cell (SEC). The expression level and its stability in the cell surface were monitored with FACS analysis. Results: Surface expression of UL18 is up-regulated by removing cytoplasmic tail portion from UL18F (a full sequence of UL18). SECs transfected with a cDNA of UL18CY (a cytoplasmic tail-less UL18) stably expressed UL18 molecule on the surface without gradual loss of its expression during 6 week continuous cultures. In the NK cytotoxicity assay, UL18 functions either inhibiting or activating NK cell cytotoxicity according to the source of NK cells. We found that there is individual susceptibility in determining whether the engagement of NK cell and UL18 results in overall inhibiting or activating NK cell cytotoxicity. Conclusion: In this study, we found that cytoplasmic tail is closely related to the regulatory function for controlling surface expression of UL18. Furthermore, by constructing stable cell line in which UL18 expression is up-regulated and stable, we provided a useful tool to clarify exact functions of UL18 on various immune cells having ILT2 receptor.

Features of Patients Associated with Falls from Heights Admitted to Republican Research Center of Emergency Medicine (우즈베키스탄 국립응급병원에 내원한 낙상환자들의 임상적인 특성)

  • Khadjibaev, Abdukhakim Muminovich;Sultanov, Pulat Karimovich;Kim, Hoon
    • Journal of Trauma and Injury
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    • v.28 no.4
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    • pp.248-255
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    • 2015
  • Purpose: study of the mutual influence of the individual anatomical regions damage in patients associated with falls from heights. Methods: 561 medical reports of patients associated with falls from heights admitted to Republican Research Center of Emergency Medicine (RRCEM), in period of 2010-2013 yy, were analyzed retrospectively. Patient's age range was from 15 to 89. Treatment of these patients held in three stages: period of acute disorders of vital functions; relative stabilization period; stabilization of vital functions. The scope and content of medical diagnostic procedures performed on pre-hospital and intensive care stages. The severity of each injury was scored according to the AIS scale, the total severity of lesions was scored by points due to ISS. Digital material is treated by methods of mathematical statistics. Results: Falls from heights leads to associated injuries for 4 times more than isolated trauma, and increases according to height of fall and falling surface. Patients with TBI+chest trauma, are most serious contingent that has highest mortality and complications (36.8%). TBI+musculoskeletal system trauma are characterized by high blood loss, traumatic shock and fat embolism, forming a vicious circle. Conclusion: in patients associated with falls from heights clinical manifestations of injuries mutual aggravation syndrome will be seen. TBI leads to complication of chest trauma, delayed diagnostics of abdominal and chest trauma, aggravation of coma condition. Developing of high blood loss and fat embolism in musculoskeletal system trauma leads to shock and pulmonary embolism, which increases probability of death in the presence of abdominal or chest trauma, but abdominal trauma or chest trauma has no significant effect on the severity of the musculoskeletal system trauma.

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A Geostatistical Study Using Qualitative Information for Tunnel Rock Binary Classificationll- II. Applcation (이분적 터널 암반 분류를 위한 정성적 자료의 지구통계학적 연구 II. 응용)

  • 유광호
    • Geotechnical Engineering
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    • v.10 no.1
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    • pp.19-26
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    • 1994
  • In this paper, the application of the rock classification method based on indicator kriging and the cost of errors, which can incorporate qualitative data, was presented. In particular, the binary classification of rock masses was considered. To this end, a simplified RMR system was used. Since most of subjectivity in this analysis occur during the estimation of loss functions, a sensitivity analysis of loss functions was performed. Through this research, it was found out that an expected cost of errors could successfully be used as an indication for how well a sampling plan was designed. In certain conditions, qualitative data can be more economical than quantitative data in terms of expected costs of errors and sampling costs. Therefore, an additional sampling should be carefully determined depending upon the surrounding geologic conditions and its sampling cost. The application method shown in this paper can be useful for more systematic rock classifications.

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