• Steel and Composite Structures
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• v.44 no.5
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• pp.651-676
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• 2022

Most of the experimental, theoretical, and numerical studies on the stability of functionally graded composites are deterministic, while there are full of complex interactions of variables with an inherently probabilistic nature, this paper presents a non-intrusive framework to investigate the stochastic nonlinear buckling behaviors of porous functionally graded cylindrical shells exposed to inevitable source-uncertainties. Euler-Lagrange equations are theoretically derived based on the three variable refined shear deformation theory. Closed-form solutions for the shell buckling loads are achieved by solving the deterministic eigenvalue problems. The analytical results are verified with numerical results obtained from finite element analyses that are conducted in the commercial software ABAQUS. The non-intrusive framework is completed by integrating the Monte Carlo simulation with the verified closed-form solutions. The convergence studies are performed to determine the effective pseudorandom draws of the simulation. The accuracy and efficiency of the framework are verified with statistical results that are obtained from the first and second-order perturbation techniques. Eleven cases of individual and compound uncertainties are investigated. Sensitivity analyses are conducted to figure out the five cases that have profound perturbative effects on the shell buckling loads. Complete probability distributions of the first three critical buckling loads are completely presented for each profound uncertainty case. The effects of the shell thickness, volume fraction index, and stochasticity degree on the shell buckling load under compound uncertainties are studied. There is a high probability that the shell has non-unique buckling modes in stochastic environments, which should be known for reliable analysis and design of engineering structures.

• Journal of Rhinology
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• v.60 no.1
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• pp.2-10
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• 2022

Background: Although the role of human papillomavirus (HPV) in sinonasal inverted papilloma (SNIP) has been investigated, the link between HPV infection and SNIP recurrence remains controversial. This meta-analysis aimed to investigate the association between HPV infection and recurrence of SNIP. Methods: The PubMed, Web of Science, Google Scholar, and Cochrane Library databases were searched (until 16 June 2021) to collect all relevant articles. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using the fixed effects model. In addition, subgroup analysis, assessment of publication bias, and sensitivity analyses were performed. Results: Fourteen eligible articles, including 592 patients with SNIP, were included in this study. Pooled analysis revealed that HPV-positive cases exhibited a significantly higher OR of tumour recurrence than HPV-negative counterparts). A significant association between HPV infection and tumour recurrence remained stable in subgroup analyses according to the publication year of the studies. Conclusions: Our meta-analysis demonstrates that HPV infection is significantly associated with the recurrence of SNIP, suggesting the pathological role of HPV in SNIP. These results suggest that HPV infection should be considered in the management of SNIP.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.365-371
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• 2007

Recent studies suggest a possible pathogenic linkage between the osteoporosis and atherosclerosis. We investigated the relationship between cardiovascular risk factors, including high sensitivity C-reactive (hs-CRP), hs-CRP and bone metabolism in females. Anthropometric measurements were performed on 300 women, and cardiovascular risk factors, including fasting blood glucose, lipid profiles and hs-CRP. An atherogenic index was calculated using the serum total cholesterol level divided by the high-density lipoprotein cholesterol level. The lumbar spine bone mineral density was measured using dual X-ray abosorptiometry. By bivariate analysis, the lumbar spine BMD showed negative correlations with age, systolic and diastolic blood pressures, serum total cholesterol, high-density lipoprotein cholesterol. The Age, BMI and high-density lipoprotein cholesterol showed significant correlations with the lumbar spine BMD. From linear regression analyses of all the study subjects, age, high-density lipoprotein cholesterol were found to be determinants of the lumbar spine BMD($R^2=0.272$).

• Journal of Korean Academy of Nursing
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• v.43 no.6
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• pp.746-759
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• 2013

Purpose: Infrared thermometers are increasingly used as a convenient, non-invasive assessment method for febrile children. However, the diagnostic accuracy of the infrared thermometer for children has been questioned, particularly in relation to sensitivity and specificity. The aim of this study was to evaluate diagnostic accuracy of infrared thermometers in febrile children. Methods: Articles published between 1966 and 2012 from periodicals indexed in the Ovid Medline, Embase, CINAHL, Cochrane, KoreaMed, NDSL, KERIS and other databases were selected, using the following keywords: 'infrared thermometer'. The QUADAS-II was applied to assess the internal validity of the diagnostic studies. Selected studies were analyzed using meta-analysis with MetaDisc 1.4. Results: Nineteen diagnostic studies with high methodological quality, involving 4,304 children, were included. The results of meta-analysis showed that the pooled sensitivity, specificity and AUC (Area Under the Curve) of infrared tympanic thermometers in children over 1 year were 0.80 (95% CI 0.78, 0.81), 0.94 (95% CI 0.93, 0.95) and 0.95 respectively. However the diagnostic accuracy of infrared tympanic thermometers in children with hyperthermia was low. Conclusion: The diagnostic accuracy of infrared tympanic thermometer was similar to axillary and rectal thermometers indicating a need for further research to substantiate these findings in children with hyperthermia.

• Mass Spectrometry Letters
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• v.7 no.2
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• pp.50-54
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• 2016

Multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) is currently used in our laboratory for isotopic and quantitative analyses of nuclear materials at ultra-trace levels in environmental swipe samples, which is a very useful for monitoring undeclared nuclear activities. In this study, to improve measurement precisions of uranium isotopes at ultratrace levels, we adopted a desolvating nebulizer system (Aridus-II, CETAC., USA), which can improve signal sensitivity and reduce formation of uranium hydride. A peristaltic pump was combined with Aridus-II in the sample introduction system of MC-ICP-MS to reduce long-term signal fluctuations by maintaining a constant flow rate of the sample solution. The signal sensitivity in the presence of Aridus-II was improved more than 10-fold and the formation ratio of UH/U decreased by 16- to 17- fold compared to a normal spray chamber. Long-term signal fluctuations were significantly reduced by using the peristaltic pump. Detailed optimizations and evaluations with uranium standards are also discussed in this paper.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7187-7193
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• 2014

Background: The aim of this meta-analysis was to compare sensitivities and specificities of fine needle aspiration (FNA) and core needle biopsy (CNB) in the diagnosis of thyroid cancer. Materials and Methods: Articles were screened in Medline, the Cochrane Library, EMBASE and Google Scholar, and subsequently included and excluded based on the patient/problem-intervention-comparison-outcome (PICO) principle. Primary outcome was defined in terms of diagnostic values (sensitivity and specificity) of FNA and CNB for thyroid cancer. Secondary outcome was defined as the accuracy of diagnosis. Compiled FNA and CNB results from the final studies selected as appropriate for meta-analysis were compared with cases for which final pathology diagnoses were available. Statistical analyses were performed for FNA and CNB for all of the selected studies together, and for individual studies using the leave-one-out approach. Results: Article selection and screening yielded five studies for meta-analysis, two of which were prospective and the other three retrospective, for a total of 1,264 patients. Pooled diagnostic sensitivities of FNA and CNB methods were 0.68 and 0.83, respectively, with specificities of 0.93 and 0.94. The areas under the summary ROC curves were 0.905 (${\pm}0.030$) for FNA and 0.745 (${\pm}0.095$) for CNB, with no significant difference between the two. No one study had greater influence than any other on the pooled estimates for diagnostic sensitivity and specificity. Conclusions: FNA and CNB do not differ significantly in sensitivity and specificity for diagnosis of thyroid cancer.

• Nuclear Engineering and Technology
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• v.32 no.4
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• pp.395-409
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• 2000

Parametric studies were performed to assess the sensitivity in determining the maximum in-vessel heat removal capability from the core material relocated into the lower plenum of the reactor pressure vessel (RPV）during a core melt accident. A fraction of the sensible heat can be removed during the molten jet delivery from the core to the lower plenum, while the remaining sensible heat and the decay heat can be transported by rather complex mechanisms of the counter-current flow limitation (CCFL) and the critical heat flux (CHF）through the irregular, hemispherical gap that may be formed between the freezing oxidic debris and the overheated metallic RPV wall. It is shown that under the pressurized condition of 10MPa with the sensible heat loss being 50% for the reactors considered in this study, i.e. TMI-2, KORI-2 like, YGN-3&4 like and KNGR like reactors, the heat removal through the gap cooling mechanism was capable of ensuring the RPV integrity as much as 30% to 40% of the total core mass was relocated to the lower plenum. The sensitivity analysis indicated that the cooling rate of debris coupled with the sensible heat loss was a significant factor The newly proposed heat removal capability map (HRCM) clearly displays the critical factors in estimating the maximum heat removal from the debris in the lower plenum. This map can be used as a first-principle engineering tool to assess the RPV thermal integrity during a core melt accident. The predictive model also provided ith a reasonable explanation for the non-failure of the test vessel in the LAVA experiments performed at the Korea Atomic Energy Research Institute (KAERI), which apparently indicated a cooling effect of water ingression through the debris-to-vessel gap and the intra-debris pores and crevices.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5125-5129
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• 2012

Economic decision models are being increasingly used to assess medical interventions. Advances in this field are mainly due to enhanced processing capacity of computers, availability of specific software to perform the necessary tasks, and refined mathematical techniques. We here estimated the incremental cost-effectiveness of ten strategies for colon cancer screening, as well as no screening, incorporating quality of life, noncompliance and data on the costs and profit of chemotherapy in Iran. We used a Markov model to measure the costs and quality-adjusted life expectancy of a 50-year-old average-risk Iranian without screening and with screening by each test. In this paper, we tested the model with data from the Ministry of Health and published literature. We considered costs from the perspective of a health insurance organization, with inflation to 2011, the Iranian Rial being converted into US dollars. We focused on three tests for the 10 strategies considered currently being used for population screening in some Iranians provinces (Kerman, Golestan Mazandaran, Ardabil, and Tehran): low-sensitivity guaiac fecal occult blood test, performed annually; fecal immunochemical test, performed annually; and colonoscopy, performed every 10 years. These strategies reduced the incidence of colorectal cancer by 39%, 60% and 76%, and mortality by 50%, 69% and 78%, respectively, compared with no screening. These approaches generated ICER (incremental cost-effectiveness ratios) of $9067, $654 and $8700 per QALY (quality-adjusted life year), respectively. Sensitivity analyses were conducted to assess the influence of various scales on the economic evaluation of screening. The results were sensitive to probabilistic sensitivity analysis. Colonoscopy every ten years yielded the greatest net health value. Screening for colon cancer is economical and cost-effective over conventional levels of WTP8.

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.127-132
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• 2009

This report examines the economic feasibility of a commercial 50,000 barrel per day direct coal liquefaction(DCL) facility to produce commercial-grade diesel and naphtha liquids from medium-sulfur bituminous coal. The scope of the study includes capital and operating cost estimates, sensitivity analysis and a comparative financial analysis. Based on plant capacity of 50,000BPD, employing Illinois #6 bituminous coal as feed coal the total capital cost appeared $3,994,858,000. Also, the internal rate of return of DCL appeared 6.60% on the base condition. In this case, coal price and sale price of products were the most influence factors. And DCL's payback period demanded a long time(12.3 years), because of high coal price at the present time. According to sensitivity analyses, the important factors on DCL processes were product sale price, feed coal price and the capital cost in order.

• Journal of Science and Technology Studies
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• v.14 no.2
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• pp.251-280
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• 2014

Although gender-mainstreaming policies have been implemented, women are still under-represented in Korean science and technology (S&T). It is necessary to systematically analyze successful strategies which improved gender-diversity in S&T institutional environment. This paper examined notable attempts to lessen gender inequality in the fields of S&T education, research and industry. In so doing, the paper makes three important arguments. First, effective strategies for gender-mainstreaming are based upon gender-sensitive analyses of institutional and cultural contexts in S&T. Second, gender-sensitive strategies can contribute not only to gender-diversity but also qualitative and quantitative improvements in S&T. Finally, the paper provides strategies to increase gender-diversity in Korean S&T.