• Title/Summary/Keyword: risk-sensitive

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An Assessment Method for Voltage Sag in Power Distribution System using a Fuzzy Model (퍼지 모델을 이용한 배전 계통에서의 순간전압강하 평가 방식)

  • Yun, Sang-Yun;O, Jeong-Hwan;Kim, Eon-Seok;Kim, Nak-Gyeong;Kim, Jae-Cheol
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.49 no.4
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    • pp.177-184
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    • 2000
  • In this paper, we proposes a method for assessing the effect of voltage sag in power distribution systems using fuzzy model. The proposed method is based on the reliability data of distribution system and specified computer business equipment manufacturer association(SCBEMA) curve that express the representative power acceptability curve by voltage sag for each customer type. The SCBEMA curves are made by using the CBEMA curves obtained from the experiment for the customers sensitive equipment. In order to transform SCBEMA curves to the differential damage by voltage sag, a fuzzy model is used. The proposed fuzzy model is composed to reflect two parameters of customers damage by voltage sag. One is the duration and magnitude of voltage sag and the other is the different risk due to the customer types. The Monte Carlo simulation method and the historical reliability data in KEPCO ae used for case studies.

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Fragility assessment for electric cabinet in nuclear power plant using response surface methodology

  • Tran, Thanh-Tuan;Cao, Anh-Tuan;Nguyen, Thi-Hong-Xuyen;Kim, Dookie
    • Nuclear Engineering and Technology
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    • v.51 no.3
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    • pp.894-903
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    • 2019
  • An approach for collapse risk assessment is proposed to evaluate the vulnerability of electric cabinet in nuclear power plants. The lognormal approaches, namely maximum likelihood estimation and linear regression, are introduced to establish the fragility curves. These two fragility analyses are applied for the numerical models of cabinets considering various boundary conditions, which are expressed by representing restrained and anchored models at the base. The models have been built and verified using the system identification (SI) technique. The fundamental frequency of the electric cabinet is sensitive because of many attached devices. To bypass this complex problem, the average spectral acceleration $S_{\bar{a}}$ in the range of period that cover the first mode period is chosen as an intensity measure on the fragility function. The nonlinear time history analyses for cabinet are conducted using a suite of 40 ground motions. The obtained curves with different approaches are compared, and the variability of risk assessment is evaluated for restrained and anchored models. The fragility curves obtained for anchored model are found to be closer each other, compared to the fragility curves for restrained model. It is also found that the support boundary conditions played a significant role in acceleration response of cabinet.

An Instrumented Workstation to Evaluate Weight-Bearing Distribution in the Sitting Posture

  • Moriguchi, Cristiane S.;Sato, Tatiana O.;Coury, Helenice J.C.G.
    • Safety and Health at Work
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    • v.10 no.3
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    • pp.314-320
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    • 2019
  • Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weight-bearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures ($p{\geq}0.40$), errors were less than 2% of participant weights an sensitivity presented statistically significant changes (p = 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

Tree-based Approach to Predict Hospital Acquired Pressure Injury

  • Hyun, Sookyung;Moffatt-Bruce, Susan;Newton, Cheryl;Hixon, Brenda;Kaewprag, Pacharmon
    • International Journal of Advanced Culture Technology
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    • v.7 no.1
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    • pp.8-13
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    • 2019
  • Despite technical advances in healthcare, the rates of hospital-acquired pressure injury (HAPI) are still high although many are potentially preventable. The purpose of this study was to determine whether tree-based prediction modeling is suitable for assessing the risk of HAPI in ICU patients. Retrospective cohort study has been carried out. A decision tree model was constructed with Age, Weight, eTube, diabetes, Braden score, Isolation, and Number of comorbid conditions as decision nodes. We used RStudio for model training and testing. Correct prediction rate of the final prediction model was 92.4 and the Area Under the ROC curve (AUC) was 0.699, which means there is about 70% chance that the model is able to distinguish between HAPI and non-HAPI. The results of this study has limited generalizability as the data were from a single academic institution. Our research finding shows that the data-driven tree-based prediction modeling may potentially support ICU sensitive risk assessment for HAPI prevention.

Digital Tourism Security System for Nepal

  • Shrestha, Deepanjal;Wenan, Tan;Khadka, Adesh;Jeong, Seung Ryul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.11
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    • pp.4331-4354
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    • 2020
  • Nepal is a sensitive and disaster-prone country where safety and security risk are of high concern for travelers. Digital technologies can play a vital role in addressing safety and security issues in the country. This research work proposes a Digital tourism security system design for addressing the safety and security issues in tourism industry of Nepal. The study uses Design science research methodology to identify artifacts, interactions, information flow and dependencies between them which are then mapped with existing prevalent technology to provide design solutions. Data is obtained from interview of tourist and experts as a primary source and technical documents/draft, software documentations, surveys as secondary source. Generalized information model, Use cases model, Network architecture model, Layered taxonomy model and Digital tourism technology reference model are the outcomes of the study. The work is very important as it talks specifically about implementation and integration of digital technologies in tourism security governance at federal, provincial, municipal and rural level. The research supplements as a knowledge document for design and implementation of digital tourism security system in practice. As there is very less work on digital systems in tourism security of Nepal, this work is a pioneer and first of its kind.

Minimum Inhibitory Concentration (MIC) of Propionic Acid, Sorbic Acid, and Benzoic Acid against Food Spoilage Microorganisms in Animal Products to Use MIC as Threshold for Natural Preservative Production

  • Yeongeun Seo;Miseon Sung;Jeongeun Hwang;Yohan Yoon
    • Food Science of Animal Resources
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    • v.43 no.2
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    • pp.319-330
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    • 2023
  • Some preservatives are naturally contained in raw food materials, while in some cases may have been introduced in food by careless handling or fermentation. However, it is difficult to distinguish between intentionally added preservatives and the preservatives naturally produced in food. The objective of this study was to evaluate the minimum inhibitory concentration (MIC) of propionic acid, sorbic acid, and benzoic acid for inhibiting food spoilage microorganisms in animal products, which can be useful in determining if the preservatives are natural or not. The broth microdilution method was used to determine the MIC of preservatives for 57 microorganisms. Five bacteria that were the most sensitive to propionic acid, benzoic acid, and sorbic acid were inoculated in unprocessed and processed animal products. A hundred microliters of the preservatives were then spiked in samples. After storage, the cells were counted to determine the MIC of the preservatives. The MIC of the preservatives in animal products ranged from 100 to 1,500 ppm for propionic acid, from 100 to >1,500 ppm for benzoic acid, and from 100 to >1,200 ppm for sorbic acid. Thus, if the concentrations of preservatives are below the MIC, the preservatives may not be added intentionally. Therefore, the MIC result will be useful in determining if preservatives are added intentionally in food.

Acute dural venous sinus thrombosis in a child with idiopathic steroid-dependent nephrotic syndrome: a case report

  • Se Jin Park;Haing-Woon Baik;Myung Hyun Cho;Ju Hyung Kang
    • Childhood Kidney Diseases
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    • v.26 no.2
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    • pp.101-106
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    • 2022
  • Nephrotic syndrome (NS) is a hypercoagulable state in which children are at risk of venous thromboembolism. A higher risk has been reported in children with steroid-resistant NS than in those with steroid-sensitive NS. The mortality rate of cerebral venous sinus thrombosis (CVST) is approximately 10% and generally results from cerebral herniation in the acute phase and an underlying disorder in the chronic phase. Our patient initially manifested as a child with massive proteinuria and generalized edema. He was treated with albumin replacement and diuretics, angiotensin-converting enzyme inhibitor, and deflazacort. Non-contrast computed tomography showed areas of hyperattenuation in the superior sagittal sinus when he complained of severe headache and vomiting. Subsequent magnetic resonance imaging revealed empty delta signs in the superior sagittal, lateral transverse, and sigmoid sinuses, suggesting acute CVST. Immediate anticoagulation therapy was started with unfractionated heparin, antithrombin III replacement, and continuous antiproteinuric treatment. The current report describes a life-threatening CVST in a child with steroid-dependent NS, initially diagnosed by contrast non-enhanced computed tomography and subsequently confirmed by contrast-enhanced magnetic resonance imaging, followed by magnetic resonance venography for recanalization, addressing successful treatment.

Toxic effects of phenanthrene on fertilization and normal embryogenesis rates of Mesocentrotus nudus and Hemicentrotus pulcherrimus (둥근성게(Mesocentrotus nudus)와 말똥성게(Hemicentrotus pulcherrimus)의 수정 및 정상 배아발생률을 이용한 Phenanthrene의 독성영향)

  • Choi, Hoon;Lee, Ju-Wook;Park, Yun-Ho;Lee, Seung-Min;Choi, Yoon-Seok;Heo, Seung;Hwang, Un-Ki
    • Korean Journal of Environmental Biology
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    • v.38 no.3
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    • pp.333-342
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    • 2020
  • The aim of this study was to define the toxic effects of phenanthrene (PAHs) on the fertilization and normal embryogenesis rates in the two species of sea urchin (Hemicentrotus pulcherrimus and Mesocentrotus nudus). The sperm and fertilized eggs of both sea urchin species were exposed to serial dilutions of phenanthrene for 10 min and 48 hours, respectively. The fertilization rate and normal embryogenesis rate of H. pulcherrimus and M. nudus were decreased in a concentration-dependent manner. The EC50 for the fertilization rate of H. pulcherrimus and M. nudus was 17.48 mg L-1 and 16.21 mg L-1, and the EC50 for the normal embryogenesis rate was 2.99 mg L-1 and 0.36 mg L-1, respectively. Between the two species, H. pulcherrimus was more sensitive to phenanthrene exposure, and 48 h normal embryogenesis was the more sensitive endpoint. Therefore, the results of this study demonstrated that the exposure of both sea urchin species to phenanthrene caused alterations in egg fertilization and the early developmental stages.

EVALUATION OF GENETIC TOXICITY FROM ENVIRONMENTAL POLLUTANTS IN DAPHNIA MAGNA AND CHIRONOMUS TENTANS FOR APPLICATION IN ECOLOGICAL RISK ASSESSMENT

  • Park, Sun-Young;Lee, Si-Won;Choi, Jin-Hee
    • Environmental Engineering Research
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    • v.11 no.5
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    • pp.277-284
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    • 2006
  • The genetic toxicity of environmental pollutants, namely, nonylphenol (NP), bisphenol A (BPA) and chloropyriphos (CP) was investigated in aquatic sentinel species, freshwater crustacean, Daphnia magna, and larva of aquatic midge, Chironomus tentans, using Comet assay. Physiological effect of such pollutants was also investigated by studying the specimens' rates of reproduction, growth and survival. Acute toxicity results showed that, as expected, Daphnia was more sensitive than Chironomus to chemical exposure. The order of acute toxicity was CP > NP > BPA in D. magna and NP > CP > BPA in C. tentans. BPA may exert a genotoxic effect on D. magna and C. tentans, given that DNA strand breaks increased in both species exposed to this compound, whereas NP- and CP-induced DNA damage occurred only in C. tentans. In vivo genotoxic data obtained in aquatic sentinel species could provide valuable information for freshwater quality monitoring. The experiments with NP-exposed D. magna showed that the pollutant has long-term effects on reproduction, whereas no short-term effect on DNA integrity was found, being an example of a false-negative result from the biomarkers perspective. This result could be interpreted that other mechanism than genetic alteration might be involved in NP-induced reproduction failure in D. magna. False-positive results from the genotoxic biomarker obtained in BPA-exposed D. magna and in NP-exposed C. tentans make it difficult to use DNA integrity as an early warning biomarker. However, as the mere presence of genotoxic compounds, which are potentially carcinogenic, is of high concern to human and ecosystem health, it could also be important to rapidly and effectively detect genotoxic compounds in the aquatic system in ways that do not necessarily accompany a higher level of alteration. Considering the potential of D. magna and C. tentans as bioindicator species, and the importance of genotoxic biomarkers in ecotoxicity monitoring, DNA damage in these species could provide useful information for environmental risk assessment.

Multiplex RT-PCR Assay for Detection of Common Fusion Transcripts in Acute Lymphoblastic Leukemia and Chronic Myeloid Leukemia Cases

  • Limsuwanachot, Nittaya;Siriboonpiputtana, Teerapong;Karntisawiwat, Kanlaya;Chareonsirisuthigul, Takol;Chuncharunee, Suporn;Rerkamnuaychoke, Budsaba
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.2
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    • pp.677-684
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    • 2016
  • Background: Acute lymphoblastic leukemia (ALL) is a heterogeneous disease which requires a risk-stratified approach for appropriate treatment. Specific chromosomal translocations within leukemic blasts are important prognostic factors that allow identification of relevant subgroups. In this study, we developed a multiplex RT-PCR assay for detection of the 4 most frequent translocations in ALL (BCR-ABL, TEL-AML1, MLL-AF4, and E2A-PBX1). Materials and Methods: A total of 214 diagnosed ALL samples from both adult and pediatric ALL and 14 cases of CML patients (154 bone marrow and 74 peripheral blood samples) were assessed for specific chromosomal translocations by cytogenetic and multiplex RT-PCR assays. Results: The results showed that 46 cases of ALL and CML (20.2%) contained the fusion transcripts. Within the positive ALL patients, the most prevalent cryptic translocation observed was mBCR-ABL (p190) at 8.41%. In addition, other genetic rearrangements detected by the multiplex PCR were 4.21% TEL-AML1 and 2.34% E2A-PBX1, whereas MLL-AF4 exhibited negative results in all tested samples. Moreover, MBCR-ABL was detected in all 14 CML samples. In 16 samples of normal karyotype ALL (n=9), ALL with no cytogentic result (n=4) and CML with no Philadelphia chromosome (n=3), fusion transcripts were detected. Conclusions: Multiplex RT-PCR provides a rapid, simple and highly sensitive method to detect fusion transcripts for prognostic and risk stratification of ALL and CML patients.