• Journal of the Korea Concrete Institute
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• v.27 no.2
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• pp.185-193
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• 2015

Ultra high performance concrete (UHPC) has been developed to overcome the low tensile strengths and brittleness of conventional concrete. Considering that UHPC, owing to its composition and the use of steel fibers, develops a compressive strength of 180 MPa as well as high stiffness, the top flange of the steel girder may be superfluous in the composite beam combining a slab made of UHPC and the steel girder. In such composite beam, the steel girder takes the form of an inverted-T shaped structure without top flange in which the studs needed for the composition of the steel girder with the UHPC slab are disposed in the web of the steel girder. This study investigates experimentally and analytically the flexural behavior of this new type of composite beam to propose details like stud spacing and slab thickness for further design recommendations. To that goal, eight composite beams with varying stud spacing and slab thickness were fabricated and tested. The test results indicated that stud spacing running from 100 mm to 2 to 3 times the slab thickness can be recommended. In view of the relative characteristic slip limit of Eurocode-4, the results showed that the composite beam developed ductile behavior. Moreover, except for the members with thin slab and large stud spacing, most of the specimens exhibited results different to those predicted by AASHTO LRFD and Eurocode-4 because of the high performance developed by UHPC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1485-1491
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• 2009

The biological compounds such as vitamin C, carotenoids, hesperidin and naringin were determined in Yuza grown in Geoje, Goseong, Gohung and Namhae. Also, activities of electron donating, nitrite scavenging and tyrosinase were detected by concentration of water extracts made from Yuza peel. Vitamin C contents of flesh sample were 6.34${\Pm}$0.12-10.74${\Pm}$1.25 mg/100 g and its contents of peel were 2.17-3.57 times higher than flesh. The carotenoid contents of peel were higher than flesh, and its contents were abundant (over 6.0 mg/100 g) in peel of Yuza grown in Goseong and Namhae-native, while Goheung-native and improved samples were detected below 3.6 mg/100 g. The contents of total phenols were the highest in flesh (11.11${\Pm}$0.10 mg/100 g) and peel (31.76 mg/100 g) of Namhae-improve Yuza. The contents of hesperidin and naringin were about 4.81-7.80, 3.07-4.62 times higher in peel than flesh. Electron donating ability of water extracts made from Yuza peel was 52.78${\Pm}$1.13-66.88${\Pm}$0.53%, in over 5 mg/mL; especially, its ability in Namhae sample was significantly high in reaction system added over 5 mg/mL of water extracts. Nitrite scavenging ability in all samples was below 30% in reaction system added 1 mg/mL of water extracts. Inhibition activity of tyrosinase in reaction system added 2.5 mg/mL of water extracts was only observed in Namhae samples, but the other samples were increased in reaction system added over 5 mg/mL of water extracts.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.5
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• pp.50-60
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• 2010

For the last half a century, the personal computer and software industries have been prosperous due to the incessant evolution of computer systems. In the 21st century, the embedded system market has greatly increased as the market shifted to the mobile gadget field. While a lot of multimedia gadgets such as mobile phone, navigation system, PMP, etc. are pouring into the market, most industrial control systems still rely on 8-bit micro-controllers and simple application software techniques. Unfortunately, the technological barrier which requires additional investment and higher quality manpower to overcome, and the business risks which come from the uncertainty of the market growth and the competitiveness of the resulting products have prevented the companies in the industry from taking advantage of such fancy technologies. However, high performance, low-power and low-cost hardware and software platforms will enable their high-technology products to be developed and recognized by potential clients in the future. This paper presents such a platform for industrial embedded systems. The platform was designed based on Telechips TCC8300 multimedia processor which embedded a variety of parallel hardware for the implementation of multimedia functions. And open-source Embedded Linux, TinyX and GTK+ are used for implementation of GUI to minimize technology costs. In order to estimate the expected performance and power consumption, the performance improvement and the power consumption due to each of enabled hardware sub-systems including YUV2RGB frame converter are measured. An analytic model was devised to check the feasibility of a new application and trade off its performance and power consumption. The validity of the model has been confirmed by implementing a real target system. The cost can be further mitigated by using the hardware parts which are being used for mass production products mostly in the cell-phone market.

• Journal of the Korea Concrete Institute
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• v.26 no.6
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• pp.761-769
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• 2014

Ultra high performance concrete (UHPC) has been developed to overcome the low strengths and brittleness of conventional concrete. Considering that UHPC, owing to its composition and the use of steel fibers, develops a compressive strength of 180 MPa as well as high stiffness, the top flange of the steel girder may be superfluous in the composite beam combining a slab made of UHPC and the steel girder. In such composite beam, the steel girder takes the form of an inverted-T shaped structure without top flange in which the studs needed for the composition of the steel girder with the UHPC slab are disposed in the web of the steel girder. This study investigates experimentally and analytically the flexural behavior of this new type of composite beam to propose details like stud spacing and slab thickness for further design recommendations. To that goal, eight composite beams with varying stud spacing and slab thickness were fabricated and tested. The test results indicated that stud spacing running from 100 mm to 2 to 3 times the slab thickness can be recommended. In view of the relative characteristic slip limit of Eurocode-4, the results showed that the composite beam developed ductile behavior. Moreover, except for the members with thin slab and large stud spacing, most of the specimens exhibited results different to those predicted by AASHTO LRFD and Eurocode-4 because of the high performance developed by UHPC.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.2
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• pp.172-180
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• 2007

Among the nuclear medicine imaging methods available today, $H_2^{15}O-PET$ is most widely used by cognitive neuroscientists to examine regional brain function via the measurement of regional cerebral blood flow (rCBF). The short half-life of the radioactively labeled probe, $^{15}O$, often allows repeated measures from the same subjects in many different task conditions. $H_2^{15}O-$ PET, however, has technical limitations relative to other methods of functional neuroimaging, e.g., fMRI, including relatively poor time and spatial resolutions, and, frequently, insufficient statistical power for analysis of individual subjects. However, recent technical developments, such as the 3-D acquisition method provide relatively good image quality with a smaller radioactive dosage, which in turn results in more PET scans from each individual, thus providing sufficient statistical power for the analysis of individual subject's data. Furthermore, the noise free scanner environment $H_2^{15}O$ PET, along with discrete acquisition of data for each task condition, are important advantages of PET over other functional imaging methods regarding studying state-dependent changes in brain activity. This review presents both the limitations and advantages of $^{15}O-PET$, and outlines the design of efficient PET protocols, using examples of recent PET studies both in the normal healthy population, and in the clinical population.

• KIPS Transactions on Computer and Communication Systems
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• v.10 no.10
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• pp.261-268
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• 2021

Cloud computing is a computing paradigm in which users can utilize computing resources in a pay-as-you-go manner. In a cloud system, resources can be dynamically scaled up and down to the user's on-demand so that the total cost of ownership can be reduced. The Modeling and Simulation (M&S) technology is a renowned simulation-based method to obtain engineering analysis and results through CAE software without actual experimental action. In general, M&S technology is utilized in Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD), Multibody dynamics (MBD), and optimization fields. The work procedure through M&S is divided into pre-processing, analysis, and post-processing steps. The pre/post-processing are GPU-intensive job that consists of 3D modeling jobs via CAE software, whereas analysis is CPU or GPU intensive. Because a general-purpose desktop needs plenty of time to analyze complicated 3D models, CAE software requires a high-end CPU and GPU-based workstation that can work fluently. In other words, for executing M&S, it is absolutely required to utilize high-performance computing resources. To mitigate the cost issue from equipping such tremendous computing resources, we propose HEMOS-Cloud service, an integrated cloud and cluster computing environment. The HEMOS-Cloud service provides CAE software and computing resources to users who want to experience M&S in business sectors or academics. In this paper, the economic ripple effect of HEMOS-Cloud service was analyzed by using industry-related analysis. The estimated results of using the experts-guided coefficients are the production inducement effect of KRW 7.4 billion, the value-added effect of KRW 4.1 billion, and the employment-inducing effect of 50 persons per KRW 1 billion.

• Journal of fish pathology
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• v.34 no.1
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• pp.71-80
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• 2021

Cephalexin, a semi-synthetic cephalosporin antibiotic, has long been used in fish aquaculture in various countries under legal authorization. The drug is thus widely available for use in other aquatic species except fishes like the crustacean whiteleg shrimp. This study aims to develop a sensitive method for laboratory residue studies to adopt in withdrawal period determinations. Through repeated trials from the existing methods developed for other food animal tissues, it was possible to achieve a sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method. The results showed that at a concentration of 0.1 mg/kg, the recovery rate was 81.79%, and C.V. value was 8.2%, which meet the recovery rate and C.V. recommended by Codex guideline. After satisfactory validation of analytical procedures, applicability to the shrimp tissue was confirmed in experimentally cephalexin-treated whiteleg shrimp. As a result, most muscle samples were detected below the limit of quantification (0.05 mg/kg) after day 3, and most hepatopancreas samples were detected below the limit of quantification after day 14. In particular, the limit of quantification 0.05 ppm with the presently developed method suggests sufficient sensitive over the current legal maximum residue limit of 0.2 mg/kg set for fishes.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.373-383
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• 2022

Inflammation caused by active oxygen and the resulting barrier damage have been consistently pointed out as the cause of wrinkle formation. In this study, effective index ingredient search and efficacy analysis were performed to verify the value of use as a functional cosmetic material related to antioxidant, anti-inflammatory and skin barrier improvement, and anti-aging for extracts of four types of Eleutherococcus divaricatus var. chiisanensis (ED), Eleutherococcus senticosus (EN), Eleutherococcus sessiliflorus (ES), and Eleutherococcus sieboldianus (EI) belonging to the Eleutherococcus genus. To identify the effective index composition, the content of the ingredients was measured by high-performance liquid chromatography. The content of eleutheroside E and chlorogenic acid was the highest in ED among the Eleutherococcus genus. As for anti-oxidant activity, DPPH radical scavenging activity was the highest in ED. In anti-inflammatory effects, ED extracts inhibited nitric oxide generation in inflammatory macrophage cells due to lipopolysaccharide by 40% at 100 ㎍/mL. In the case of IL-6 inhibition, which is known as a pro-inflammatory cytokine, ED showed 41% inhibition at 100 ㎍/mL. In addition, filaggrin and involucrin, which are skin barrier-related factors, were increased by 2.5 times and 1.6 times, respectively, in 100 ㎍/mL of ED extracts, and as for the collagenase, which is a wrinkle-related factor, ED extract showed 29% efficacy at 100 ㎍/mL. Thus, these result suggested that ED extract, among the four Eleutherococcus genus, can be used as a cosmetic ingredient for suppressing inflammation in the skin, reinforcing the skin barrier, and reducing wrinkles.

• Journal of Intelligence and Information Systems
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• v.28 no.4
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• pp.251-273
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• 2022

Recently, research on applying text analysis to deep learning has steadily continued. In particular, researches have been actively conducted to understand the meaning of words and perform tasks such as summarization and sentiment classification through a pre-trained language model that learns large datasets. However, existing pre-trained language models show limitations in that they do not understand specific domains well. Therefore, in recent years, the flow of research has shifted toward creating a language model specialized for a particular domain. Domain-specific pre-trained language models allow the model to understand the knowledge of a particular domain better and reveal performance improvements on various tasks in the field. However, domain-specific further pre-training is expensive to acquire corpus data of the target domain. Furthermore, many cases have reported that performance improvement after further pre-training is insignificant in some domains. As such, it is difficult to decide to develop a domain-specific pre-trained language model, while it is not clear whether the performance will be improved dramatically. In this paper, we present a way to proactively check the expected performance improvement by further pre-training in a domain before actually performing further pre-training. Specifically, after selecting three domains, we measured the increase in classification accuracy through further pre-training in each domain. We also developed and presented new indicators to estimate the specificity of the domain based on the normalized frequency of the keywords used in each domain. Finally, we conducted classification using a pre-trained language model and a domain-specific pre-trained language model of three domains. As a result, we confirmed that the higher the domain specificity index, the higher the performance improvement through further pre-training.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.216-224
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• 2022

This study was aimed at validating the analysis methods for deacetylasperulosidic acid (DAA), total sugar, galacturonic acid, glucose, and galactose, which are the indicator components of fermented Morinda citrifolia polysaccharide extract (Vitalbos). We modified the previously reported methods for validating the analytical methods. The specificity, linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ) were measured using phenol-sulfuric acid method and high-performance liquid chromatography (HPLC). The retention time and spectrum of the standard solution of Vitalbos coincided, confirming the specificity. The calibration curve correlation coefficient (R²), of five indicator components, ranged from 0.9995-0.9998, indicating excellent linearity of 0.99 or more. The intra-day and inter-day precision range of the assay was 0.14-3.01%, indicating a precision of less than 5%. The recovery rate was in the range of 95.13-105.59%, presenting excellent accuracy. The LOD ranged from 0.39 to 0.84 ㎍/mL and the LOQ ranged from 1.18 to 2.55 ㎍/mL. Therefore, the analytical method was validated for DAA, total sugar, galacturonic acid, glucose, and galactose, in Vitalbos. The indicator component content in Vitalbos was determined using a validated method. The contents of DAA, total sugar, galacturonic acid, glucose, and galactose were 2.31±0.06, 475.92±5.95, 72.83±1.05, 71.63±2.44, and 67.30±2.31 mg/g of dry weight, respectively. These results suggest that the developed analytical method is efficient and could contribute to the quality control of Vitalbos, as a healthy functional food material.