• 제목/요약/키워드: Impact Analyses

검색결과 1,445건 처리시간 0.027초

폴리카보네이트 판의 경사충격에 의한 도비 거동 수치연구 (Numerical Study on Ricochet Behavior with Inclined Impact of Polycabonate Plates)

  • 양태호;이영신;조종현
    • 한국안전학회지
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    • 제29권4호
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    • pp.1-8
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    • 2014
  • In this study, the numerical simulation using AUTODYN-3D program was investigated angle trajectory prediction for inclined impacts of projectiles. The penetration and perforation of polycarbonate plate by 7.62 mm projectile was investigated numerically. The characteristic structure of the projectile's trajectory in the polycabonate plates was studied. Two combined failure criteria were used in the target plate, and the target plate was modeled with the properties of polycarbonate for simulating the ricochet phenomenon. The effect of the angle of inclination on the trajectory and kinetic energy of the projectile were studied. The dynamic deformation behaviors tests of polycabonate were compared with numerical simulation results which can be used as predictive purpose. From the simulation, the ricochet phenomenon was occurred for angles of inclination of $0^{\circ}{\leq}{\theta}{\leq}20^{\circ}$. The projectile perforated the plate for ${\theta}{\leq}30^{\circ}$, thus defining a failure envelope for numerical configuration. The numerical analyses are used to study the effect of the projectile impact velocity on the depth of penetration (DOP). It can be observed that the residual velocities were almost linear relative to penetration velocities. It means that polycarbonate has high resistance at higher velocities.

Investigation of structural responses of breakwaters for green water based on fluid-structure interaction analysis

  • Lee, Chi-Seung;Heo, Haeng-Sung;Kim, Young-Nam;Kim, Myung-Hyun;Kim, Sang-Hyun;Lee, Jae-Myung
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제4권2호
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    • pp.83-95
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    • 2012
  • In the present study, the structural response of breakwaters installed on container carriers against green water impact loads was numerically investigated on the basis of the fluid-structure interaction analysis. A series of numerical studies is carried out to induce breakwater collapse under such conditions, whereby a widely accepted fluid-structure interaction analysis technique is adopted to realistically consider the phenomenon of green water impact loads. In addition, the structural behaviour of these breakwaters under green water impact loads is investigated simultaneously throughout the transient analysis. A verification study of the numerical results is performed using data from actual collapse incidents of breakwaters on container carriers. On the basis of the results of a series of numerical analyses, the pressure distribution of green water was accurately predicted with respect to wave mass and velocity. It is expected that the proposed analytical methodology and predicted pressure distribution could be used as a practical guideline for the design of breakwaters on container carriers.

국내 농업기후지대 별 최적기후모형 선정을 통한 미래 벼 도열병 발생 위험도 예측 (Predicting Potential Epidemics of Rice Leaf Blast Disease Using Climate Scenarios from the Best Global Climate Model Selected for Individual Agro-Climatic Zones in Korea)

  • 이성규;김광형
    • 한국기후변화학회지
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    • 제9권2호
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    • pp.133-142
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    • 2018
  • Climate change will affect not only the crop productivity but also the pattern of rice disease epidemics in Korea. Impact assessments for the climate change are conducted using various climate change scenarios from many global climate models (GCM), such as a scenario from a best GCM or scenarios from multiple GCMs, or a combination of both. Here, we evaluated the feasibility of using a climate change scenario from the best GCM for the impact assessment on the potential epidemics of a rice leaf blast disease in Korea, in comparison to a multi?model ensemble (MME) scenario from multiple GCMs. For this, this study involves analyses of disease simulation using an epidemiological model, EPIRICE?LB, which was validated for Korean rice paddy fields. We then assessed likely changes in disease epidemics using the best GCM selected for individual agro?climatic zones and MME scenarios constructed by running 11 GCMs. As a result, the simulated incidence of leaf blast epidemics gradually decreased over the future periods both from the best GCM and MME. The results from this study emphasized that the best GCM selection approach resulted in comparable performance to the MME approach for the climate change impact assessment on rice leaf blast epidemic in Korea.

A Study on the Mediating Effect of Perceived Usefulness in the Acceptance of Airport Service Technology

  • PARK, Hyeyoon
    • 융합경영연구
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    • 제8권1호
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    • pp.1-11
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    • 2020
  • Purpose - In the aviation industry, we will investigate the impact of users' acceptance of technology on their usage behavior and find out the factors that affect their acceptance of technology. We will expand the prior study to find out the impact of the self-service technology of Incheon Airport. Research design, data, and Methodology - The thesis was conducted on people using self-service technology at Incheon International Airport from July to August 2019. Part 307 of the valid questionnaires were used for this final analysis. The collected data were used to perform frequency, factor, reliability, and multiple regression analyses using the SPSS statistical package. Result - Individual aspects of external variables, service aspects, and systems aspects have been shown to affect usability and perceived ease of use. Usability and convenience have been shown to serve as intermediaries for users' technological acceptance. Conclusion - The perceived convenience and usefulness of Incheon International Airport has been shown to affect self-service users, while convenience and usefulness have been shown to serve as intermediaries for technology acceptance purposes. In other words, raising expectations for convenience, rapid processing, benefits and so on will have a positive impact on the intent to accept.

The Impact of Corporate Governance on the Quality of Integrated Reporting: International Evidence

  • ELSHANDIDY, Tamer
    • The Journal of Asian Finance, Economics and Business
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    • 제9권6호
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    • pp.127-137
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    • 2022
  • This paper aims to investigate the impact of corporate governance on the quality of integrated reporting. Corporate governance includes internal (board size, board independence, and board diversity) and external (audit quality and enforcement) governance factors. This paper develops an index to capture the quality of integrated reporting by employing the completeness of information required by the International Integrated Reporting Council (IIRC). For an international sample, the paper manually collects 160 integrated reports along with internal and external governance factors and employs multivariate analyses to examine the association between these governance factors and the quality of integrated reporting. The empirical results suggest that firms with a larger board of directors, a larger proportion of female members on board, and located in countries with enforcement for integrated reporting requirements have a higher quality of integrated reporting. Our conclusions still hold after accounting for several conditions, including the industry-fixed and year-fixed effects. Together, these results suggest that both internal and external governance factors are important determinants for the quality of integrating reporting. These results have several theoretical and practical implications as they fulfill the absence of relevant studies on addressing the impact of internal and external corporate governance factors on the quality of integrated reporting.

The Impact of Senior Mobility Funding on Hearing Aid Acquisition and Compliance to Hearing Aid Use in a Singapore Hospital

  • Chua Wei De, Kenneth
    • Journal of Audiology & Otology
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    • 제25권1호
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    • pp.8-13
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    • 2021
  • Background and Objectives: In 2013, the Singapore government reviewed and expanded the Senior Mobility Fund (SMF) to provide subsidy for assistive devices, including hearing aids (HA). While SMF has improved accessibility to HA, its impact on HA acquisition has not been determined. The study aims to elucidate the influence of SMF on HA acquisition and the relationship between financial funding and compliance to HA use. Subjects and Methods: Retrospective review of 643 patients seen between January 2017 to January 2018 at the earnose and throat specialist outpatient clinic, who were referred for a hearing aid evaluation. Of the 643 patients, 109 patients with baseline hearing handicap (HH) scores recorded, and no formal diagnosis of cognitive impairment were included. The patients were grouped according to SMF eligibility and clinical data were obtained. Results: The odds ratio for acquiring HA was significantly higher with SMF, regardless of HH scores. When looking at actual degree of hearing loss (DHL), HA uptake was significantly higher in the least severe of DHL categories. There is no relationship between SMF and compliance to HA use. However, HH score is positively correlated with data log in regression analyses. Conclusions: SMF appears to influence HA acquisition. Especially in financially funded patients with low self-perceived HH, the benefits of HA may be underappreciated given the few hours of HA use. Further studies are warranted to investigate the impact of financial funding on outcomes of HA users to help policy planners and clinicians be prudent in the utilization of SMF.

The Impact of Senior Mobility Funding on Hearing Aid Acquisition and Compliance to Hearing Aid Use in a Singapore Hospital

  • De, Kenneth Chua Wei
    • 대한청각학회지
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    • 제25권1호
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    • pp.8-13
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    • 2021
  • Background and Objectives: In 2013, the Singapore government reviewed and expanded the Senior Mobility Fund (SMF) to provide subsidy for assistive devices, including hearing aids (HA). While SMF has improved accessibility to HA, its impact on HA acquisition has not been determined. The study aims to elucidate the influence of SMF on HA acquisition and the relationship between financial funding and compliance to HA use. Subjects and Methods: Retrospective review of 643 patients seen between January 2017 to January 2018 at the earnose and throat specialist outpatient clinic, who were referred for a hearing aid evaluation. Of the 643 patients, 109 patients with baseline hearing handicap (HH) scores recorded, and no formal diagnosis of cognitive impairment were included. The patients were grouped according to SMF eligibility and clinical data were obtained. Results: The odds ratio for acquiring HA was significantly higher with SMF, regardless of HH scores. When looking at actual degree of hearing loss (DHL), HA uptake was significantly higher in the least severe of DHL categories. There is no relationship between SMF and compliance to HA use. However, HH score is positively correlated with data log in regression analyses. Conclusions: SMF appears to influence HA acquisition. Especially in financially funded patients with low self-perceived HH, the benefits of HA may be underappreciated given the few hours of HA use. Further studies are warranted to investigate the impact of financial funding on outcomes of HA users to help policy planners and clinicians be prudent in the utilization of SMF.

Mechanical and Thermal Properties of Liquefied Wood Polymer Composites (LWPC)

  • Hyun, Doh Geum;Kang, In Aeh;Lee, Sun Young;Kong, Young To
    • Journal of the Korean Wood Science and Technology
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    • 제32권6호
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    • pp.67-73
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    • 2004
  • The influence of liquefied wood (LW) on the mechanical and thermal properties of liquefied wood-polymer composites (LWPC) was investigated in this study. The thermal behaviors of LWPC were characterized by means of thermogravimetric (TGA) and differential scanning calorimetric (DSC) analyses. LW showed significant effects on the mechanical strength properties. The increase of flexural MOE and Young's modulus was related to the increase of stiffness of LWPC. The effect of LW was also significant on the flexural and tensile MOR. The impact strength decreased with the increase of LW application level. With the increased stress concentration by the poor bonding between LW and polymer, the impact strength of LWPC decreased, compared with that of high-density polyethylene (HDPE). The thermal stability of LWPC decreased with the increase of LW content up to 40%. The melting temperature of HDPE decreased with the increase of LW loading level. Enthalpy of HDPE also decreased with the addition of LW. This study proves the thermal stability necessary for the consolidation of composition materials.

The Moderating Effect of COVID-19 on the Promotion, Distribution and Sales of Dairy Products in Western India: An Exploratory Study

  • SINGH, Sanjit;KOTALA, Siva Sai Madhumitha;SINGH, Prakash;V, Sai Krishna;YAMALA, Karthik
    • 유통과학연구
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    • 제20권6호
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    • pp.11-19
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    • 2022
  • Purpose: This study aims at exploring and understanding the effect of four independent variables related to dairy retail marketing and distribution (deep freezers, promotions, company support and distributor-retailer relationship) and one moderating variable Covid-19 lockdown on sales of dairy product during the Covid 19 pandemic situation. Research design and methodology: Personal interviews and door-to-door surveys and promotional tools were designed to publicise and collect data from the retailers. The sale data before, during and after promotion activity were all recorded and evaluated to draw an inferential conclusion. Factor analysis and multiple regression methods were adopted to analyses the data collected. Results: The research shows that four out of the five factors studied was found having significant impact on dairy retail sales. The highest impact on sales was contributed by promotions, secondly by the deep freezer impact followed by distributor-retailer relationship during the study period and lastly but not the least due to influence of Covid-19 lockdown. Conclusions: The study contributes to the body of knowledge in cold chain distribution process through utilization of right mix of tools and tactics for effective marketing and distribution of dairy products in developing countries especially during a pandemic situation.

The Impact of Geopolitical Risk on Financial Conditions of Emerging Economies

  • BAJAJ, Namarta Kumari;AZIZ, Tariq;KUMARI, Sonia;ALENEZI, Marim;MATHKUR, Naif Mansour
    • The Journal of Asian Finance, Economics and Business
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    • 제10권1호
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    • pp.133-143
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    • 2023
  • The detrimental impacts of financial instability on the world economy during the financial crisis highlighted the requirement to understand the existing financial circumstances. Stability and developments in financial conditions are important for economic prosperity. This study analyses the impact of geopolitical risk on the economic conditions of some specific emerging economies using monthly data from January 1999 to September 2016 by applying a fixed-effects panel data model. The estimation results demonstrated that geopolitical risk has a significant, negative impact on financial conditions. It shows geopolitical risk could be seen as a key factor that contributes towards financial conditions. Further, it implies that negative shocks of high geopolitical risk experienced by emerging economies are one of the primary reasons for the financial conditions' deterioration. The findings provide important insights for governments, policymakers, and investors. For instance, governments and politicians should refrain from expressing or producing tension, economic discomfort, or news that is likely to increase a high geopolitical risk. Maintaining a close eye on geopolitical risk and its sources may also help to stabilize financial conditions and develop a well-functioning financial system. As a result, investors would be better informed about an economy's economic and financial conditions, allowing them to diversify their international portfolios and devise investing strategies during uncertain economic times.