• Computers and Concrete
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• v.11 no.2
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• pp.105-121
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• 2013

This paper investigates the parameters that control the design of Fiber Reinforced Polymer (FRP) reinforced concrete flexural members proportioned following the ACI 440.1R-06. It investigates the critical parameters that control the flexural design, such as the deflection limits, crack limits, flexural capacity, concrete compressive strength, beam span and cross section, and bar diameter, at various Mean-Ambient Temperatures (MAT). The results of this research suggest that the deflection and cracking requirements are the two most controlling limits for FRP reinforced concrete flexural members.

• Computers and Concrete
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• v.9 no.1
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• pp.35-50
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• 2012

The 2D representative volume element (RVE) for softening quasi-brittle materials like concrete is determined. Two alternative methods are presented to determine a size of RVE in concrete subjected to uniaxial tension by taking into account strain localization. Concrete is described as a heterogeneous three-phase material composed of aggregate, cement matrix and bond. The plane strain FE calculations of strain localization at meso-scale are carried out with an isotropic damage model with non-local softening.

• Computers and Concrete
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• v.1 no.3
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• pp.285-302
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• 2004

A FE-(FE-HE)-BE procedure is presented for dynamic analysis of concrete arch dams. In this technique, dam body is discretized by solid finite elements, while the reservoir domain is considered by a combination of fluid finite elements and a three-dimensional fluid hyper-element. Furthermore, foundation rock domain is handled by three-dimensional boundary element formulation. Based on this method, a previously developed program is modified, and the response of Morrow Point arch dam is studied for various conditions. Moreover, the effects of canyon shape on response of dam, is also discussed.

• Computers and Concrete
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• v.4 no.1
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• pp.49-66
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• 2007

The objective of this paper is to provide experimental data on the propagation of curved crack-surfaces and the respective load-displacement diagrams for the validation of numerical models for cracking of concrete, subjected to three-dimensional stress states. To this end beam-shaped specimens are subjected to combined bending and torsional loading, leading to the formation of a spatially curved crack-surface. The experimental data contain the evolution of the load and of the strains at selected points in terms of the crack mouth opening displacement and the propagation of the crack surface.

• Computers and Concrete
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• v.27 no.1
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• pp.63-71
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• 2021

In this study, a new stopping criterion, called "backward controlled stopping criterion" (BCSC), was proposed to be used in Genetic Algorithms. In the study, the available stopping citeria; adaptive stopping citerion, evolution time, fitness threshold, fitness convergence, population convergence, gene convergence, and developed stopping criterion were applied to the following four comparison problems; high strength concrete mix design, pre-stressed precast concrete beam, travelling salesman and reinforced concrete deep beam problems. When completed the analysis, the developed stopping criterion was found to be more accomplished than available criteria, and was able to research a much larger area in the space design supplying higher fitness values.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1616-1620
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• 2001

Two feeding trials were conducted to study the effects of different chelated copper and zinc compounds on the performance and fecal excretions of weanling pigs. In Exp. 1, 150 weanling pigs ($L{\times}Y{\times}D$, $12.30{\pm}2.07kg$) were randomly assigned to five dietary treatments: 170 ppm Cu from $CuSO_4$, 85 ppm Cu from Cu amino-chelate (CAC), 170 ppm Cu from CAC, 85 ppm Cu from Cu-Lysine (CL), and 170 ppm Cu from CL. In Exp. 2, 150 weanling pigs ($L{\times}Y{\times}D$, $12.52{\pm}1.80kg$) were randomly assigned to five dietary treatments: 120 ppm Zn from $ZnSO_4$, 60 ppm Zn from Zn-amino-chelate (ZAC), 120 ppm Zn from ZAC, 60 ppm Zn from Zn-Methionine (ZM), and 120 ppm Zn from ZM. In both experiments, pigs were randomly distributed to the treatments following a randomized complete block design on the basis of body weight as the blocking variable. Each experiment was conducted for 28 days. Blood and fecal samples were collected to determine mineral contents as affected by the dietary treatments. There was no difference (p>0.05) in ADG and ADFI among treatments, but F/G was improved (p<0.05) in pigs fed diet with 170 ppm CAC than 85 ppm CL but not different (p>0.05) to the control (170 ppm $CuSO_4$). Regardless of copper source, concentration of Cu in serum and feces were higher in pigs fed diet with 170 ppm Cu than pigs fed diet with 85 ppm Cu (Exp 1). In Exp 2 the ADG was higher (p<0.05) in pigs fed diet with 120 ppm ZM than in pigs fed diets with 120 ppm $ZnSO_4$ and 60 ppm ZAC and ZM. The serum zinc concentration was generally higher (p<0.05) in pigs fed diet with organic source than the control group ($ZnSO_4$). Also, there was a trend towards a decrease in fecal excretions of zinc when dietary zinc level was low. The efficacy of the two chelated copper and zinc sources is similar in terms of growth performance. The fecal excretions for Cu and Zn could be reduced in pigs fed low level of these minerals using organic sources.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.305-314
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• 2011

The purpose of this study was to compare the findings on the chest low-dose CT (LDCT) images between the negative and positive groups for pneumoconiosis in the group exposed to inorganic dust. From May 30, 2007 to August 31, 2008, total 328 subjects were examined by a LDCT. LDCT images were read by a chest radiologist who has much experience for reading of pneumoconiosis. All subjects were classified into two groups based on digital images after consensus reading of two radiologists according to the ILO 2000 guidelines; negative group (87, 26.5%) without pneumoconiosis and positive group (241, 73.5%). Statistical analysis was performed using a SPSS 14.0. There were significant differences in age (60.9 vs. 65.0, p<0.001), and in dust expose duration (17.0 vs. 19.2, p=0.024) between two groups, but no significant difference in smoking (p=0.784). Of the 328 subjects, 13 diagnosis were extracted from 245 subjects (74.7%). Coronary artery calcification (CAC) was significantly higher in positive group than that in negative group (36.9% vs. 25.3%, p=0.049). Honeycombing showed higher frequency in positive group than in negative group (6.2% vs. 1.2%, p=0.079). Pneumoconiosis findings caused by inorganic dusts exposure showed the significant relation with CAC on LDCT images. Future studies need to prove that pneumoconiosis finding is independent risk factor for CAC using a coronary artery angiography.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.87-93
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• 2019

Revision work on the Codex Classification of Foods and Animal Feeds was undertaken in 2007 and presently, revisions for most food groups have been completed. For vegetables, the work was conducted during 2014-2017, and the final draft revision was adopted by the $40^{th}$ Codex Alimentarius Commission (2017). Here, the revised classification of vegetable commodities is introduced in order to be utilized in various food-related fields, in particular, food safety regulation. The revised classification is briefly summarized as follows: Codex classified vegetables into 10 groups (Group 009-018): bulb vegetables (Group 009), Brassica vegetables (except Brassica leafy vegetables) (Group 010), fruiting vegetables, Cucurbits (Group 011), fruiting vegetables, other than Cucurbits (Group 012), leafy vegetables (including Brassica leafy vegetables) (Group 013), legume vegetables (Group 014), pulses (Group 015), root and tuber vegetables (Group 016), stalk and stem vegetables (Group 017) and edible fungi (Group 018). The groups are further divided into a total of 33 subgroups. In the Classification, 430 different commodity codes are assigned to vegetable commodities. Meanwhile, Korea's Ministry of Food and Drug Safety (MFDS) does not include potatoes, beans and mushrooms within a vegetable group. In addition, the MFDS divides one vegetable group into six subgroups including flowerhead Brassicas, leafy vegetables, stalk and stem vegetables, root and tuber vegetables, fruiting vegetables, Cucurbits, and fruiting vegetables other than Cucurbits. Therefore, care is needed in using the Codex Classification.

• Korean Journal of Radiology
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• v.23 no.10
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• pp.998-1008
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• 2022

Objective: The present study aimed to assess the relationship between incidental abnormalities on thoracic computed tomography (CT) and mortality in a general screening population using a long-term follow-up analysis. Materials and Methods: We retrospectively collected the medical records and CT images of 840 participants (mean age ± standard deviation [SD], 58.5 ± 6.7 years; 564 male) who underwent thoracic CT at a single health promotion center between 2007 and 2010. Two thoracic radiologists independently reviewed all CT images and evaluated any incidental abnormalities (interstitial lung abnormality [ILA], emphysema, coronary artery calcification [CAC], aortic valve [AV] calcification, and pulmonary nodules). Kaplan-Meier analysis with log-rank and z-tests was performed to assess the relationship between incidental CT abnormalities and all-cause mortality in the subsequent follow-up. Cox proportional hazards regression was performed to further identify risk factors of all-cause mortality among the incidental CT abnormalities and clinical factors. Results: Among the 840 participants, 55 (6%), 171 (20%), 288 (34%), 396 (47%), and 97 (11%) had findings of ILA, emphysema, CAC, pulmonary nodule, and AV calcification, respectively, on initial CT. The participants were followed up for a mean period ± SD of 10.9 ± 1.4 years. All incidental CT abnormalities were associated with all-cause mortality in univariable analysis (p < 0.05). However, multivariable analysis further revealed fibrotic ILA as an independent risk factor for all-cause mortality (hazard ratio, 2.52 [95% confidence interval, 1.02-6.22], p = 0.046). ILA were also identified as an independent risk factor for lung cancer or respiratory disease-related deaths. Conclusion: Incidental abnormalities on screening thoracic CT were associated with increased mortality during the long-term follow-up. Among incidental CT abnormalities, fibrotic ILA were independently associated with increased mortality. Appropriate management and surveillance may be required for patients with fibrotic ILA on thoracic CT obtained for general screening purposes.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.268-275
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• 2010

Coronary artery calcium scores(CACS) has been used as surrogate marker for coronary atherosclerosis. We evaluated 1042 patients who visited the Department of Health Promotion Center in Chonnam National University Hospital and had a test of the CACS from January 2006, to December 2008. This study was performed to evaluate the relation of the CACS with Cadiovascular disease(CVD) risk factors and FRS. CACS and FRS was a significant difference between the group whose calcium score was 0 and the group whose calcium scores were 1 in case of men 2.38(95% CI, 1.83-3.11), women 2.12(95% CI, 1.03-4.35). The age-and sex-adjusted odds ratios for predictor of CVD risk factors to women with age was 1.10(95% CI, 1.06-1.15), HDL-cholesterol was 2.38(95% CI, 1.04-5.44), Fasting plasma glucose was 2.89(95% CI, 1.16-7.21), to men with age was 1.11(95% CI, 1.08-1.14), LDL-cholesterol was 2.12(95% CI, 1.28-3.50), gamma-GTP was 1.73(95% CI, 1.17-2.55), Diabetes mellitus medication was 3.92(95% CI, 1.73-8.89). The CACS seems to be a siginificant factor to evaluate the CVD risk factors.