• 제목/요약/키워드: Variability Types

검색결과 288건 처리시간 0.03초

Estimation of carbon storage in coastal wetlands and comparison of different management schemes in South Korea

  • Byun, Chaeho;Lee, Shi-Hoon;Kang, Hojeong
    • Journal of Ecology and Environment
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    • 제43권1호
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    • pp.61-72
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    • 2019
  • Background: Organic carbon stored in coastal wetlands, which comprises the major part of oceanic "blue carbon," is a subject of growing interest and concern. In this study, organic carbon storage in coastal wetlands and its economic value were estimated using the raw data of 25 studies related to soil carbon storage. Data were collected from three tidal flats (one protected and two developed areas) and two estuarine salt marshes (one protected and one restored area). Bulk density, soil organic matter content, and standing biomass of vegetation were all considered, with Monte Carlo simulation applied to estimate the uncertainty. Results: Mean carbon storage in two salt marshes ranged between 14.6 and $25.5kg\;C\;m^{-2}$. Mean carbon storage in tidal flats ranged from 18.2 to $28.6kg\;C\;m^{-2}$, with variability possibly related to soil texture. The economic value of stored carbon was estimated by comparison with the price of carbon in the emission trading market. The value of US $ $6600\;ha^{-1}$ is ~ 45% of previously estimated ecosystem services from fishery production and water purification functions in coastal areas. Conclusions: Although our study sites do not cover all types of large marine ecosystem, this study highlights the substantial contribution of coastal wetlands as carbon sinks and the importance of conserving these habitats to maximize their ecosystem services.

유전자 질병 관련도 분석을 위한 소프트웨어 플랫폼 (Software Platform for Analyzing Gene and Disease Relevance)

  • 송명호;김수동
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제8권2호
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    • pp.51-60
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    • 2019
  • 많은 질병들이 정복되면서 삶의 질을 향상시키지만, 유전병들은 많은 분석 및 연구가 필요하다. 이러한 질병과 유전자 관련도를 분석할 때 다양한 요구사항이 존재하고, 알고리즘 최적화 유무로 인해 런타임 효율성이 저하된다. 본 논문은 유전자 질병 관련도 분석 플랫폼을 소개하고 위의 이슈를 해결하기 위한 분석 API와 두가지 런타임 효율성 최적화 알고리즘을 제시한다. 그리고 제시한 분석 API를 이용하여 관련도 측정 실험을 진행, 두 최적화 알고리즘의 결과와 비교했다. 첫 번째 알고리즘은 이전 실험과 같은 결과를 적은 시간에 도출했고, 두 번째 알고리즘은 이전 실험들에 비해 낮은 정확도의 결과를 더 적은 시간에 도출했다. 따라서 본 플랫폼을 통해 여러 방식의 유전자와 질병 관련도를 효율적으로 얻을 수 있다.

Seismic protection of LNG tanks with reliability based optimally designed combined rubber isolator and friction damper

  • Khansefid, Ali;Maghsoudi-Barmi, Ali;Khaloo, Alireza
    • Earthquakes and Structures
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    • 제16권5호
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    • pp.523-532
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    • 2019
  • Different types of gas reservoir such as Liquid Natural Gas (LNG) are among the strategic infrastructures, and have great importance for any government or their private owners. To keep the tank and its contents safe during earthquakes especially if the contents are of hazardous or flammable materials; using seismic protection systems such as base isolator can be considered as an effective solution. However, the major deficiency of this system can be the large deformation in the isolation level which may lead to the failure of bearing system. In this paper, as a solution, the efficacy of an optimally designed combined vibration control system, the combined laminated rubber isolator and rotational friction damper, is investigated to evaluate the enhancement of an existing metal tank response under both far- and near-field earthquakes. Responses like impulsive and convective accelerations, base shear, and sloshing height are studied herein. The probabilistic framework is used to consider the uncertainties in the structural modeling, as well as record-to-record variability. Due to the high calculation cost of probabilistic methods, a simplified structural model is used. By using the Mont-Carlo simulation approach, it is revealed that this combined isolation system is a highly reliable system which provides considerable enhancement in the performance of reservoir, not only leads to the reduction of probability of catastrophic failure of the tank but also decrease the reservoir damage during the earthquake. Moreover, the relative displacement of the isolation level is controlled very well by this combined system.

A case with GRIN2A mutation and its non-neurological manifestations

  • Lee, Soo Yeon;Jung, So Yoon;Lee, Jeongho
    • Journal of Genetic Medicine
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    • 제17권2호
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    • pp.79-82
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    • 2020
  • In epilepsy-aphasia spectrum (EAS) disorders, mutations in the glutamate receptor ionotropic N-methyl-D-aspartate type subunit 2A (GRIN2A) have become important for screening the disease. Research into the phenotypic variability of several types of neurologic impairment involving these mutations is in progress. However, the non-neurological problems related to these mutations are poorly understood. EAS disorders usually have epileptic, cognitive, or behavioral manifestations. In this case report, we present a female patient with epilepsy, delay in expressive language and social development, and intellectual disability with low intelligence quotient and memory quotient, but normal motor development. Through genetic analysis, she was found to have a missense and a nonsense mutation in GRIN2A (c.1770A>C; p.Lys509Asn and c.3187G>T; p.Glu1063∗, respectively) and we consider the nonsense mutation as 'pathogenic variant'. She was also discovered to have congenital hypothyroidism, growth hormone deficiency and Rathke's cleft cyst in the brain, which were previously unknown features of GRIN2A mutation. Our findings should widen understanding of the spectrum of GRIN2A phenotypes, and emphasize the need for more research into the association between GRIN2A mutations and non-neurologic clinical presentations.

Assessing Publication Productivity of the Top 10 Countries Across Medical Specialties: Prolific Versus Prestigious Journals

  • Kim, Eungi;Lee, Yong-Gu
    • Journal of Information Science Theory and Practice
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    • 제10권2호
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    • pp.74-85
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    • 2022
  • This study aimed to investigate publication productivity in various medical specialties in the top 10 countries with the highest number of published journal articles, considering the distinction between prolific and prestigious journals. For this study, we selected 10 specialties from the Scientific Journal Rankings (SJR) and used journals listed in both SJR and PubMed. Bibliographic details of these journals' articles published from 2017 to 2019 were downloaded from PubMed. The results showed that various aspects of medical publication output were influenced by country characteristics such as specialty, journal type, population size, wealth, and healthcare expenditure. China showed the greatest variability in terms of specialty, as its publications in Oncology (ONCGY) were exceptionally high compared with the specialties of other countries. China's publications in ONCGY exceeded even those of the United States in ONCGY. Furthermore, the western countries, the United Kingdom, Canada, and the United States in particular published more articles in prestigious journals than the other top 10 countries, where the East Asian countries published more articles in prolific journals than in prestigious journals.

Longitudinal Variation of Fish Communities in the Geum River, Korea: Application of the Concept of Beta Diversity and Local Uniqueness

  • Kim, Jeong-Hui;Park, Sang-Hyeon;Baek, Seung-Ho;Hong, Donghyun;Jo, Hyunbin
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제3권2호
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    • pp.122-128
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    • 2022
  • To present the spatial variation of fish assemblages in the Geum River in Korea, the concept of beta diversity (β-diversity) estimates based on the variance of the community data table was applied. Fish communities and environmental variables were collected from 13 sampling sites along the in mid-low reaches of the River. We calculated the β-diversity and local contribution to beta diversity (LCBD) values at each site depending on the two types of data, 'occurrence' with Jaccard and Sørensen dissimilarity coefficients, and 'abundance' with Hellinger distance. Multivariate and correlation analyses were also performed to determine the relationships between LCBD and other variables, such as community indices and physicochemical and hydrological factors. The β-diversity values of fish communities in the River were estimated as 0.218 and 0.145 for occurrence data table with Jaccard and Sørensen respectively, and 0.268 for abundance data. Similar patterns of LCBD along the sampling sites were detected in two dissimilarity measurements of occurrence table, and LCBD values with abundance data were slightly different. The LCBD values are strongly correlated with community indices, and also suitable for indicating the uniqueness of fish assemblages. However, further research is needed to determine the LCBD value as an indicator of environmental variability.

On the models for the distribution of examination score for projecting the demand for Korean Long-Term Care Insurance

  • Javal, Sophia Nicole;Kwon, Hyuk-Sung
    • Communications for Statistical Applications and Methods
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    • 제28권4호
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    • pp.393-410
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    • 2021
  • The Korean Long-Term Care Insurance (K-LTCI) provides financial support for long-term care service to people who need various types of assistance with daily activities. As the number of elderly people in Korea is expected to increase in the future, the demand for long-term care insurance would also increase over time. Projection of future expenditure on K-LTCI depends on the number of beneficiaries within the grading system of K-LTCI based on the test scores of applicants. This study investigated the suitability of mixture distributions to the model K-LTCI score distribution using recent empirical data on K-LTCI, provided by the National Health Insurance Service (NHIS). Based on the developed mixture models, the number of beneficiaries in each grade and its variability under the current grading system were estimated by simulation. It was observed that a mixture model is suitable for K-LTCI score distribution and may prove useful in devising a funding plan for K-LTCI benefit payment and investigating the effects of any possible revision in the K-LTCI grading system.

Classification Trends Taxonomy of Model-based Testing for Software Product Line: A Systematic Literature Review

  • Sulaiman, Rabatul Aduni;Jawawi, Dayang Norhayati Abang;Halim, Shahliza Abdul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권5호
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    • pp.1561-1583
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    • 2022
  • Context: Testing is one of the techniques that can assure the quality of software including the domain of Software Product Line (SPL). Various techniques have been deliberated to enhance the quality of SPL including Model-based Testing (MBT). Objective: The objective of this study is to analyze and classify trends of MBT in SPL covering the solutions, issues and evaluation aspects by using taxonomy form. Method: A Systematic Literature Review (SLR) was conducted involving 63 primary studies from different sources. The selected studies were categorized based on their common characteristics. Results: Several findings can guide future research on MBT for SPL. The important finding is that the multiple measurements are still open to improving current metrics to evaluate test cases in MBT for SPL. The multiple types of measurement required a trade-off between maximization and minimization results to ensure the testing method which could satisfy multiple test criteria for example cost and effectiveness at the same time.

태양광 모듈용 봉지재 종류에 따른 자외선 광열화 연구 (Research on Ultraviolet Light Degradation According to Types of Encapsulants for PV Modules)

  • 어승아;정낙현;김주휘;이찬용;이재형
    • Current Photovoltaic Research
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    • 제11권4호
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    • pp.108-113
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    • 2023
  • Pressure to reduce costs in the current solar market is driving the development and implementation of new module designs and prompting the use of new materials and components. In order to utilize the variability of each material that makes up the module, it is essential to understand the basic characteristics of the material. In this article, we evaluate light degradation after UV irradiation as an encapsulation material. Measure and analyze the results of various characteristic tests for discoloration, optical and electrical property degradation before and after UV accelerated testing. To evaluate weathering stability, UV tests were performed comparing existing EVA and UVT-EVA, POE and improved low-cost POE. Even in the weather resistance test with a total UV exposure of 60 kW/m2, the properties of the encapsulants were mostly stable. EVA and POE-based encapsulants showed slight differences, and these slight differences are believed to pose a threat to long-term stability. This study is a basic analysis of encapsulation research for PV modules and will be helpful in understanding future development and encapsulant properties.

Comparative Evaluation of Egg Quality in Response to Temperature Variability: From Farm to Table Exposure Scenarios

  • Ji-Hoon An;Youngmin Hwang;Sumin Hwang;Hyojin Kwon;Hyelim Gu;Kihwan Park;Changsun Choi
    • 한국축산식품학회지
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    • 제43권6호
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    • pp.1002-1016
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    • 2023
  • This study aimed to develop appropriate temperature management practices and provide scientific evidence to support the development of sell-by-date guidance for eggs. Washed and unwashed eggs were subjected to storage under six different scenarios, and both types of eggs were stored at temperatures up to 35℃ to evaluate the sell-by-date. Despite temperature fluctuations or continuous storage at 30℃ for 5 days, subsequent storage at 10℃ resulted in significantly higher Haugh unit and yolk index on day 15. These results indicate that refrigerating eggs from retail sales until consumption is effective for egg quality management, despite the exposure of up to 35℃ during distribution. In terms of sell-by-date evaluation, washed eggs retained class B quality for an additional 37 days beyond the recommended sell-by-date at 15℃, which is above the regulated storage temperature. However, unwashed eggs maintained class B quality for approximately 20 days at 30℃-35℃, emphasizing the need for sell-by-date guidelines for unwashed eggs. This study is the first to provide appropriate egg-handling practices based on the actual distribution environment in Korea.