• Title/Summary/Keyword: Abnormal Impact

Search Result 240, Processing Time 0.026 seconds

Impact of abnormal climate events on the production of Italian ryegrass as a season in Korea

  • Kim, Moonju;Sung, Kyungil
    • Journal of Animal Science and Technology
    • /
    • v.63 no.1
    • /
    • pp.77-90
    • /
    • 2021
  • This study aimed to assess the impact of abnormal climate events on the production of Italian ryegrass (IRG), such as autumn low-temperature, severe winter cold and spring droughts in the central inland, southern inland and southern coastal regions. Seasonal climatic variables, including temperature, precipitation, wind speed, relative humidity, and sunshine duration, were used to set the abnormal climate events using principal component analysis, and the abnormal climate events were distinguished from normal using Euclidean-distance cluster analysis. Furthermore, to estimate the impact caused by abnormal climate events, the dry matter yield (DMY) of IRG between abnormal and normal climate events was compared using a t-test with 5% significance level. As a result, the impact to the DMY of IRG by abnormal climate events in the central inland of Korea was significantly large in order of severe winter cold, spring drought, and autumn low-temperature. In the southern inland regions, severe winter cold was also the most serious abnormal event. These results indicate that the severe cold is critical to IRG in inland regions. Meanwhile, in the southern coastal regions, where severe cold weather is rare, the spring drought was the most serious abnormal climate event. In particular, since 2005, the frequency of spring droughts has tended to increase. In consideration of the trend and frequency of spring drought events, it is likely that drought becomes a NEW NORMAL during spring in Korea. This study was carried out to assess the impact of seasonal abnormal climate events on the DMY of IRG, and it can be helpful to make a guideline for its vulnerability.

Abnormal Sound from Heat Exchanger of Condensate Water System at Nuclear Power Plant (원전 복수계통 열교환기의 이음 원인 분석)

  • Lee, Jun-Shin;Lee, Wook-Ryun;Kim, Tae-Ryong
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.26 no.4
    • /
    • pp.469-474
    • /
    • 2016
  • Abnormal sound was heard from a heat exchanger of condensate water system in a nuclear power plant, which was identified as impact sound of a loose part later. Nuclear power plants are normally equipped with loose part monitoring system for primary water system, but not for secondary water system. The abnormal sound was analyzed by using the impact signal-processing methodology based on the Hertz theory. The predicted results for impact location and size of the loose part showed good agreement with those of the actual loose part found during the overhaul period in the plant. So, this analysis methodology for the impact signal will be widely utilized for the primary and secondary side of the nuclear power plant.

Real Earnings Management and Persistence of Firm Value: Evidence from India

  • POTHARLA, Srikanth;BHATTACHARJEE, Kaushik;SAMONTARAY, Durga Prasad
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.12
    • /
    • pp.323-336
    • /
    • 2021
  • The present study aims to examine the impact of real earnings management on the future value of the firm and its persistence. The study also tests suspect firm effects on the relationship between real earnings management and the future value of the firm. The sample of the present study consists of all listed non-financial firms from the year 2011 to 2018. Real earnings management has been measured in three alternative ways viz., abnormal operating cash flows, abnormal discretionary spending, and abnormal production cost. Tobin's Q is used as a measure of firm value. The interaction term of real earnings management and Tobin's Q is used to test firm value persistence. The results of the analysis disclose that out of three measures of real earnings management, abnormal reduction in discretionary spending only has a significant negative impact on the persistence of firm value. Moreover, the suspect firm analysis reveals that when the underlying motive of real earnings management is to meet zero earnings, both abnormal increases in operating cash flows and abnormal reduction in discretionary spending have a significant negative impact on firm value persistence.

Lateral Damper of Subway Vehicle for Preventing Abnormal Impact (지하철 전동차 비정상 충격 방지를 위한 횡댐퍼에 관한 연구)

  • Shin, Yujeong;You, Wonhee;Park, Joonhyuk;Hur, Hyunmoo;Jeon, Juyun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.37 no.1
    • /
    • pp.17-23
    • /
    • 2013
  • In a subway vehicle, a lateral damper is used for compensating the lateral stiffness deterioration due to the air-spring as a secondary suspension. This lateral damper can reduce the lateral vibration of the carbody. When the damping force of the lateral damper is lowered, the running stability and ride quality of the subway vehicles worsens and the lateral motion of the carbody is increased. In this study, the lateral displacement variation of the carbody according to the damping force of the lateral damper was analyzed by multi-body dynamics to solve the abnormal impact problem during vehicle operation. Furthermore, the noise and vibration due to abnormal impact were considered. An adequate damping coefficient of the lateral damper for the subway vehicle treated in this paper was suggested for preventing abnormal impact.

Analysis of the Impact of Heatwaves in Gwangju using Logistic Regression and Discriminant Analysis (로지스틱 회귀분석과 판별분석을 활용한 광주광역시의 폭염에 미치는 영향분석)

  • Youn Su Kim;Yeong Seon Kong;In Hong Chang
    • Journal of Integrative Natural Science
    • /
    • v.17 no.2
    • /
    • pp.33-41
    • /
    • 2024
  • Abnormal climate is a phenomenon in which meteorological factors such as temperature and precipitation are significantly higher or lower than normal, and is defined by the World Meteorological Organization as a 30-year period. However, over the past 30 years, abnormal climate phenomena have occurred more frequently around the world than in the past. In Korea, abnormal climate phenomena such as abnormally high temperatures on the Korean Peninsula, drought, heatwave and heavy rain in summer are occurring in March 2023. Among them, heatwaves are expected to increase in frequency compared to other abnormal climates. This suggests that heatwave should be recognised as a disaster rather than just another extreme weather event. According to several previous studies, greenhouse gases and meteorological factors are expected to affect heatwaves, so this paper uses logistic regression and discriminant analysis on meteorological element data and greenhouse gas data in Gwangju from 2008 to 2022. We analyzed the impact of heatwaves. As a result of the analysis, greenhouse gases were selected as effective variables for heatwaves compared to the past, and among them, chlorofluorocarbons were judged to have a stronger effect on heatwaves than other greenhouse gases. Since greenhouse gases have a significant impact on heatwaves, in order to overcome heatwaves and abnormal climates, greenhouse gases must be minimized to overcome heatwaves and abnormal climates.

Root-Cause Investigation of Abnormal Sound from a Heat Exchanger of Condensate Water System in a Nuclear Power Plant (원전 복수계통 열교환기의 이음발생 원인규명)

  • Lee, Jun-Shin;Kim, Tae-Ryong;Lee, Wook-Ryun;Sohn, Seok-Man;Yoon, Seok-Bon;Kim, Man-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2006.05a
    • /
    • pp.1306-1311
    • /
    • 2006
  • The root cause of abnormal sound from a heat exchanger of condensate water system in a nuclear power plant is investigated by using the impact signal-processing methodology based on the Hertz theory. The predicted results for the location of impact force and the loose part size meet good agreement with the identified materials during the overhaul period in the plant. Nuclear power plants have experienced several loose parts and the frequency of the loose part will be increased along the aging of the plants. So, this analysis methodology for the impact signal will be widely utilized for the primary and secondary side of the nuclear power plant.

  • PDF

The Impact of Stock Split Announcements on Stock Prices: Evidence from Colombo Stock Exchange

  • PRABODINI, Madhara;RATHNASINGHA, Prasath Manjula
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.9 no.5
    • /
    • pp.41-51
    • /
    • 2022
  • The research looks into the impact of stock split announcements on stock prices and market efficiency in the Colombo Stock Exchange (CSE). This research uses a sample of 26 stock split announcements that occurred between 2020 and June 2021. According to the Global Industry Classification Standards, the stock split announcements covered in the study pertain to 26 businesses and 9 industries (GICS). To obtain the results, the usual event research methodology is used. The findings demonstrate significant average abnormal returns of 15.01 percent on the day the stock split news is made public and abnormal returns of 4.11 percent and -4.05 percent one day before and after the stock split announcement date, respectively. The study's findings revealed significant positive abnormal returns one day before the disclosure date, indicating information leakage, and significant negative abnormal returns the next day after the announcement date, indicating CSE informational efficiency. Because stock prices adapt so quickly to public information, these findings support the semi-strong form efficient market hypothesis, which states that investors cannot gain an abnormal return by trading in stocks on the day of the stock split announcement.

Impact of Complex Hemodynamics to the Management of ArterioVenous(AV) Fistula (동정맥루의 복합성 혈류학 소견이 그 관리에 미치는 영향)

  • Lee Byung-Boons
    • Proceedings of the KSME Conference
    • /
    • 2002.08a
    • /
    • pp.9-10
    • /
    • 2002
  • Human circulatory system between heart and tissue is not directly connected in normal condition but mandatory to go through the capillary system in order to fulfill its physiologic aim to deliver oxygen and nutrients, etc. to the tissue and retrieve used blood together with waste products from the tissue properly. When abnormal connection between arterial and venous system (AV fistula), these two circulatory systems respond differently to the hemodynamic impact of this abnormal connection between high pressure (artery) and low pressure (vein) system. Depending upon the location and/or degree (e.g. size and flow) of fistulous condition, each circulatory system exerts different compensatory hemodynamic response to this newly developed abnormal inter-relationship between two systems in order to minimize its hemodynamic impact to own system of different hemodynamic characteristics. Pump action of the heart can assist the failing arterial system directly to maintain arterial circulation against newly established low peripheral resistance by the AV fistula during the compensation period, while it affects venous system in negative way with increased venous loading. However, the negative impact of increased heart action to the venous system is partly compensated by the lymphatic system which is the third circulatory system to assist venous system independently with different hemodynamics. The lymphatic system with own unique Iymphodynamics based on peristaltic circulation from low resistance to high resistance condition, also increases its circulation to assist the compensation of overloaded venous system. Once these compensation mechanisms should fail to fight to newly established hemodynamic condition due to this abnormal AV connection, each system start to show different physiologic ${\underline{de}compensation}$ including heart and lymphatic system. The vicious cycle of decompensation between arterial and vein, two circulatory system affecting each other by mutually negative way steadily progresses to show series of hemodynamic change throughout entire circulation system altogether including heart. Clinical outcome of AV fistula from the compensated status to decompensated status is closely affected by various biological and mechanical factors to make the hemodynmic status more complicated. Proper understanding of these crucial biomechanical factors iii particular on hemodyanmic point of view is mandatory for the advanced assessment of biomechanical impact of AV fistula, since this new advanced concept of AY fistula based on blomechanical information will be able to improve clinical control of the complicated AV fistula, either congenital or acquired.

  • PDF

A Study on the Earnings Permanence and the Incremental Information Content of Earnings and Cash Flows (이익영속성과 이익 및 현금흐름의 증분정보내용에 관한 연구)

  • 박상욱
    • Journal of the Korea Society of Computer and Information
    • /
    • v.5 no.3
    • /
    • pp.151-158
    • /
    • 2000
  • This dissertation measures transitory items using earnings change scaled by beginning-of-period price(FreemanㆍTse 1992) and the earnings-to-price ratio(AliㆍZarowin 1992). Contextual regression model results confirm the incremental explanatory power for predominantly permanent earnings, and suggest that cash flows also have incremental explanatory power in the presence of predominantly permanent earnings. But contextual regression results represent that while earnings are consistent with a smaller marginal impact from extreme (transitory) earnings on abnormal returns, cash flows have no greater impact on abnormal returns in the presence of large transitory components in earnings.

  • PDF

The Analysis of High Chlorophyll-a Concentration Patch in the North Marine Areas of East China Sea (동중국해 북부 해역의 엽록소 고농도 덩어리 분석)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
    • /
    • v.23 no.3
    • /
    • pp.220-226
    • /
    • 2014
  • This study investigated temporal-spatial and variations in Geostationary Ocean Color Imager (GOCI) products of parameters total suspended solids (TSS) and chlorophyll-a in the North Marine Areas of East China Sea.GOCI data were collected daily from February 2012 to December 2012. The higher chlorophyll-a values were observed during the investigation period. The relatively large increase in TSS and chlorophyll-a at the sampling stations coupled with typhoon events during the summer rainy period. The abnormal chlorophyll-a concentration was mainly driven by meteorological factors such as typhoon and rainfall in the coastal areas of Jeju and the North Marine Areas of East China Sea. The abnormal high chlorophyll-a concentration at the majority of the coastal stations indicate eutrophication of coastal waters, especially Red tide. The events such as eutrophication and abnormal high chlorophyll-a concentration may potentially influence outbreak of Red Tide, detected with GOCI parameters.