• 제목/요약/키워드: Loss distribution

검색결과 2,130건 처리시간 0.03초

Does Disposition Effect Appear on Investor Decision During the COVID-19 Pandemic Era: Empirical Evidence from Indonesia

  • ASNAWI, Said Kelana;SIAGIAN, Dergibson;ALZAH, Salam Fadillah;HALIM, Indra
    • The Journal of Asian Finance, Economics and Business
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    • 제9권4호
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    • pp.53-62
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    • 2022
  • Disposition Effect (DE) is one of the many investment biases, wherein the investors sell the profitable stocks rather quickly and they tend to hold on the loss making stocks. Various factors related to the DE are the character of investors applying risk management which is also influenced by the social media, Salient Shock (COVID-19), and in the specific case of Indonesia, the phenomenon of rumor stocks wherein the price can rise as much as up to 8500%. The study aims to provide empirical evidence regarding the DE with specific explanatory factors, namely investor behavior and rumors. Data was obtained through a questionnaire sent to 248 Indonesian Stock Exchange Investors (IDX) during the period October-November 2021 by using Ordinary Least Square (OLS) method. The results show: Generation Z, women, and investors with a low education has a greater DE, risk-takers tend to have lower DE, and professionals have negative DE. Implementation of risk management will reduce DE. Social Media and the COVID-19 situation positively affect DE. Especially on stock rumors, there is evidence that investors who own rumor stocks will have a low DE. The results indicate the need for: (i) risk management, especially for Z Generation, women and low education Investors, (ii) to provide positive information so that information on social media can be responded to positively.

강화 남부 조간대에 서식하는 칠면초(Suaeda japonica)의 연간 생장 및 생산 양상 (Growth Rate and Annual Production of Halo-phyte (Suaeda japonica) on Tidal Mud-flat, Southern Part of Ganghwa-Isl, Korea)

  • 황지원;이균우;박흥식
    • Ocean and Polar Research
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    • 제44권2호
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    • pp.127-137
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    • 2022
  • This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m2/yr, and the highest production was 519 gDWt/m2/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m2/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

테이핑 방법에 따른 유연성 평발의 족저압 및 보행 특성 변화 (Changes in Plantar Pressure and Gait Characteristics in Adults with Asymptomatic Flexible Pes Planus by Different Taping)

  • 김종순
    • PNF and Movement
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    • 제20권2호
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    • pp.167-177
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    • 2022
  • Purpose: Pes planus is a common foot deformity that involves the loss of the medial longitudinal arch. The medial longitudinal arch deformity is usually asymptomatic; however, it can lead to an increased risk of pain and injury. Low-Dye taping is designed to treat plantar heel pain and pes planus. However, low-Dye taping is relatively complex, and a considerable amount of time is required to apply the tape correctly. The purpose of this study was to compare the acute effect of two different types of taping (low-Dye taping and modified Mulligan taping) on arch reformation, plantar pressure, and gait characteristics in participants with asymptomatic flexible pes planus. Methods: Twenty subjects (9 males and 11 females; mean age = 21.95 years) with asymptomatic flexible pes planus voluntarily participated in this study. Arch reformation was evaluated using navicular height measurements. Changes in plantar pressure distribution were measured using BioRecue equipment. Gait parameters were measured using spatiotemporal data collected during consecutive gait cycles using a G-WALK device. One-way analysis of variance was used to compare the three different conditions (i.e., bare foot, low-Dye taping, and modified Mulligan taping) for each variable. Results: Navicular height was significantly increased in subjects who underwent the two types of taping compared to those who experienced the bare foot condition. The plantar pressure was significantly shifted to the posterolateral area after modified Mulligan taping compared with the bare foot condition. There were no significant differences in the gait parameters. Conclusion: The findings of this study indicate that modified Mulligan taping has a similar effect to low-Dye taping, and modified Mulligan taping is a simpler method than low-Dye taping.

Auranofin accelerates spermidine-induced apoptosis via reactive oxygen species generation and suppression of PI3K/Akt signaling pathway in hepatocellular carcinoma

  • Hyun Hwangbo;Da Hye Kim;Min Yeong Kim;Seon Yeong Ji;EunJin Bang;Su Hyun Hong;Yung Hyun Choi;JaeHun Cheong
    • Fisheries and Aquatic Sciences
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    • 제26권2호
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    • pp.133-144
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    • 2023
  • Auranofin is a US Food and Drug Administration (FDA)-approved anti-arthritis medication that functions as a thioredoxin reductase inhibitor. Spermidine, a polyamine present in marine algae, can exert various physiological functions. Herein, we examined the synergistic anticancer activity of auranofin and spermidine in hepatocellular carcinoma (HCC). Combined treatment with auranofin and spermidine suppressed cell viability more efficiently than either treatment alone in HCC Hep3B cells. The isobologram plotted by calculating the half maximal inhibitory concentration (IC50) values of each drug indicated that the two drugs exhibited a synergistic effect. Based on the analysis of annexin V and cell cycle distribution, auranofin and spermidine markedly induced apoptosis in Hep3B cells. Moreover, auranofin and spermidine increased mitochondria-mediated apoptosis by promoting mitochondrial membrane potential (Δψm) loss. Auranofin and spermidine significantly increased reactive oxygen species (ROS) production in Hep3B cells, and the blocking ROS suppressed apoptosis induced by spermidine and auranofin. In addition, auranofin and spermidine reduced the expression of phosphorylated phosphatidylinositol-3 kinase (PI3K) and protein kinase B (Akt), and PI3K inhibitor accelerated auranofin- and spermidine-induced apoptosis. Using ROS scavenger and PI3K inhibitor, we revealed that ROS acts upstream of auranofin- and spermidine-induced apoptosis. Collectively, our study suggests that combination treatment with auranofin and spermidine could afford synergistic anticancer activity via ROS overproduction and reduced PI3K/Akt signaling pathway.

코로나 확진자 수 예측을 위한 BI-LSTM과 GRU 알고리즘의 성능 비교 분석 (Comparative analysis of performance of BI-LSTM and GRU algorithm for predicting the number of Covid-19 confirmed cases)

  • 김재호;김장영
    • 한국정보통신학회논문지
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    • 제26권2호
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    • pp.187-192
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    • 2022
  • 위드 코로나의 예정 발표일이 결정되었고, 위드 코로나에 가장 중요한 조건인 백신 접종을 아직 부작용 걱정 때문에 완료하지 않은 사람들이 있다. 또한 위드 코로나로 경제는 회복될 수 있지만 감염자 수는 급증할 수 있다. 본 논문은 위드 코로나에 앞서 코로나19에 대한 경각심을 깨우고자, 코로나19를 비선형 확률과정으로 예측한다. 여기서 딥러닝의 RNN중 양방향 LSTM인 BI-LSTM와 LSTM보다 gate수를 줄인 GRU를 사용하고 이것을 train set, test set, 손실함수, 잔차분석, 정규분포, 자기 상관을 통해서 비교 분석하여 어떠한 성능이 더 좋은지 비교하고 예측한다.

Comparison of soil erosion simulation between empirical and physics-based models

  • Yeon, Min Ho;Kim, Seong Won;Jung, Sung Ho;Lee, Gi Ha
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2020년도 학술발표회
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    • pp.172-172
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    • 2020
  • In recent years, soil erosion has come to be regarded as an essential environmental problem in human life. Soil erosion causes various on- and off-site problems such as ecosystem destruction, decreased agricultural productivity, increased riverbed deposition, and deterioration of water quality in streams. To solve these problems caused by soil erosion, it is necessary to quantify where, when, how much soil erosion occurs. Empirical erosion models such as the Universal Soil Loss Equation (USLE) family models have been widely used to make spatially distributed soil erosion vulnerability maps. Even if the models detect vulnerable sites relatively well by utilizing big data related to climate, geography, geology, land use, etc. within study domains, they do not adequately describe the physical process of soil erosion on the ground surface caused by rainfall or overland flow. In other words, such models remain powerful tools to distinguish erosion-prone areas at the macro scale but physics-based models are necessary to better analyze soil erosion and deposition and eroded particle transport. In this study, the physics-based Surface Soil Erosion Model (SSEM) was upgraded based on field survey information to produce sediment yield at the watershed scale. The modified model (hereafter MoSE) adopted new algorithms on rainfall kinematic energy and surface flow transport capacity to simulate soil erosion more reliably. For model validation, we applied the model to the Doam dam watershed in Gangwon-do and compared the simulation results with the USLE outputs. The results showed that the revised physics-based soil erosion model provided more improved and reliable simulation results than the USLE in terms of the spatial distribution of soil erosion and deposition.

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Force-deformation relationship prediction of bridge piers through stacked LSTM network using fast and slow cyclic tests

  • Omid Yazdanpanah;Minwoo Chang;Minseok Park;Yunbyeong Chae
    • Structural Engineering and Mechanics
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    • 제85권4호
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    • pp.469-484
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    • 2023
  • A deep recursive bidirectional Cuda Deep Neural Network Long Short Term Memory (Bi-CuDNNLSTM) layer is recruited in this paper to predict the entire force time histories, and the corresponding hysteresis and backbone curves of reinforced concrete (RC) bridge piers using experimental fast and slow cyclic tests. The proposed stacked Bi-CuDNNLSTM layers involve multiple uncertain input variables, including horizontal actuator displacements, vertical actuators axial loads, the effective height of the bridge pier, the moment of inertia, and mass. The functional application programming interface in the Keras Python library is utilized to develop a deep learning model considering all the above various input attributes. To have a robust and reliable prediction, the dataset for both the fast and slow cyclic tests is split into three mutually exclusive subsets of training, validation, and testing (unseen). The whole datasets include 17 RC bridge piers tested experimentally ten for fast and seven for slow cyclic tests. The results bring to light that the mean absolute error, as a loss function, is monotonically decreased to zero for both the training and validation datasets after 5000 epochs, and a high level of correlation is observed between the predicted and the experimentally measured values of the force time histories for all the datasets, more than 90%. It can be concluded that the maximum mean of the normalized error, obtained through Box-Whisker plot and Gaussian distribution of normalized error, associated with unseen data is about 10% and 3% for the fast and slow cyclic tests, respectively. In recapitulation, it brings to an end that the stacked Bi-CuDNNLSTM layer implemented in this study has a myriad of benefits in reducing the time and experimental costs for conducting new fast and slow cyclic tests in the future and results in a fast and accurate insight into hysteretic behavior of bridge piers.

데이터 선별 및 클래스 세분화를 적용한 실시간 해양 침적 쓰레기 감지 AI 시스템 구현과 성능 개선 방법 연구 (A Study on the Implementation of Real-Time Marine Deposited Waste Detection AI System and Performance Improvement Method by Data Screening and Class Segmentation)

  • 왕태수;오세영;이현서;최동규;장종욱;김민영
    • 문화기술의 융합
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    • 제8권3호
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    • pp.571-580
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    • 2022
  • 해양침적쓰레기는 유령어업으로 인한 폐어구들로 인해 많은 피해와 쓰레기 추정량 편차 증가 등의 문제를 일으키는 주요 원인이 된다. 본 논문에서는 폐어구 사용량, 유통량, 유실량, 회수량에 대한 실태 파악을 위해 실시간 해양침적쓰레기 감지 인공지능 시스템을 구현하고, 성능 개선을 위한 방법에 대해 연구한다. 실시간 객체인식에 우수한 성능모델인 yolov5모델을 활용하여 시스템을 구현하였고, 성능개선 방법으로는 학습데이터의 '데이터 선별 과정'과 '클래스 세분화' 방법을 적용하였다. 결론적으로 비선별된 데이터셋과 클래스가 세분화된 데이터셋의 객체인식 결과보다 불필요한 데이터를 선별하거나 특징 및 용도에 따라 유사 항목을 세분화 하지 않은 데이터셋의 객체인식 결과는 해양침적쓰레기 인식에 개선된 결과를 보인다.

Object Detection Based on Deep Learning Model for Two Stage Tracking with Pest Behavior Patterns in Soybean (Glycine max (L.) Merr.)

  • Yu-Hyeon Park;Junyong Song;Sang-Gyu Kim ;Tae-Hwan Jun
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.89-89
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    • 2022
  • Soybean (Glycine max (L.) Merr.) is a representative food resource. To preserve the integrity of soybean, it is necessary to protect soybean yield and seed quality from threats of various pests and diseases. Riptortus pedestris is a well-known insect pest that causes the greatest loss of soybean yield in South Korea. This pest not only directly reduces yields but also causes disorders and diseases in plant growth. Unfortunately, no resistant soybean resources have been reported. Therefore, it is necessary to identify the distribution and movement of Riptortus pedestris at an early stage to reduce the damage caused by insect pests. Conventionally, the human eye has performed the diagnosis of agronomic traits related to pest outbreaks. However, due to human vision's subjectivity and impermanence, it is time-consuming, requires the assistance of specialists, and is labor-intensive. Therefore, the responses and behavior patterns of Riptortus pedestris to the scent of mixture R were visualized with a 3D model through the perspective of artificial intelligence. The movement patterns of Riptortus pedestris was analyzed by using time-series image data. In addition, classification was performed through visual analysis based on a deep learning model. In the object tracking, implemented using the YOLO series model, the path of the movement of pests shows a negative reaction to a mixture Rina video scene. As a result of 3D modeling using the x, y, and z-axis of the tracked objects, 80% of the subjects showed behavioral patterns consistent with the treatment of mixture R. In addition, these studies are being conducted in the soybean field and it will be possible to preserve the yield of soybeans through the application of a pest control platform to the early stage of soybeans.

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SDN 환경에서 실시간 데이터 유입형태를 고려한 효율적인 부하분산 기법 연구 (A Study on the Efficient Load Balancing Method Considering Real-time Data Entry form in SDN Environment)

  • 김주성;권태욱
    • 한국전자통신학회논문지
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    • 제18권6호
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    • pp.1081-1086
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    • 2023
  • 현대 네트워크의 급속한 성장과 복잡성 증가는 전통적인 네트워크 아키텍처의 한계를 부각시켰다. 이러한 과제에 대응한 SDN(Software-Defined Network)의 등장은 기존의 네트워크 환경을 변화시켰다. SDN은 제어부와 데이터부를 분리하고 중앙 집중식 컨트롤러를 사용하여 네트워크 동작을 조정한다. 하지만 이러한 구조도 최근 수많은 IoT(Internet of Things) 기기의 급속한 확산으로 엄청난 양의 트래픽이 발생하게 되었고 이는 네트워크의 전송 속도를 느리게 할 뿐 아니라 QoS(Quality of Service)를 보장하기 어렵게 만들었다. 이에 본 논문에서는 어느 특정 IP에서 다량의 데이터가 유입되는 경우 즉, 서버 과부화 및 데이터 손실이 발생하게 되어 전체적인 네트워크 지연이 발생할 시 기존의 데이터처리 스케줄링 기법인 RR(Round-Robin) 방식에서 해당 IP와 임의의 서버(처리기)를 Mapping 하는 방식으로 전환하여 데이터를 부하분산하는 기법을 제안하고자 한다.