• Journal of Environmental Science International
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• v.28 no.5
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• pp.485-494
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• 2019

The purpose of this study was to investigate the improvement effect of 5% turmeric (Curcuma longa L.) on the blood glucose and lipid metabolism function of streptozotocin (STZ, 45 mg/kg body weight)-induced diabetic rats. Seven-week-old male rats were divided into four groups (n=6), and fed experimental diets containing turmeric meal [basal diet+5% turmeric (BT), basal diet+STZ+5% turmeric (ST)], and control (BD), BS groups (basal diet+STZ). The results of this study, turmeric diet groups (BT, ST) in lipid component as evidenced from the significantly reduction of serum total cholesterol, low density lipoprotein-cholesterol (LDL-cholesterol), atherosclerotic index (AI), cardiac risk factor (CRF), triglyceride (TG), phospholipid (PL), free cholesterol, cholesteryl ester, uric acid, blood glucose, non esterified fatty acid (NEFA), and elevation of high density lipoprotein-cholesterol (HDL-cholesterol). The serum albumin and globulin contents were increased in turmeric supplementation diet than STZ-induced diabetic rats (p<0.05). Concentrations of sodium (Na) and chlorine (Cl) in sera were lower in the turmeric diet than diabetic group. Total calcium (T-Ca), phosphorus (Pi) and potassium (K) concentrations in sera were higher in the BT, ST and BD groups than BS group. In vivo experiments with Sprague-Dawley rats showed that ingestion of turmeric (Curcuma longa L.) were effective in the blood glucose and lipid metabolism functional improvement.

• Current Photovoltaic Research
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• v.4 no.1
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• pp.1-7
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• 2016

Among the various types of solar cells, silicon based two terminal tandem solar cell is one of the most popular one. It is designed to split the absorption of incident AM1.5 solar radiation among two of its component cells, thereby widening the wavelength range of external quantum efficiency (EQE) spectra of the device, in comparison to that of a single junction solar cell. In order to improve the EQE spectra further and raise short circuit current density ($J_{sc}$) an optimization of the tradeoff between the top and bottom cell is needed. In an optimized cell structure, the $J_{sc}$ and hence efficiency of the device can further be enhanced with the help of light trapping scheme. This can be achieved by texturing front and back surface as well as a back reflector of the device. In this brief review we highlight the development of light trapping in the silicon based tandem solar cell.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.8 s.251
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• pp.772-779
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• 2006

Window is a critical component in the design of energy-efficient buildings. To minimize the heat loss, insulation performance of the glazing has to be improved. Manufacturing of vacuum glazing has been motivated by the possibility of making windows of very good thermal insulation properties for such applications. It is made by maintaining vacuum in the gap between two glass panes. Pillars are placed between them to withstand the atmospheric pressure. Edge covers are applied to reduce conduction through the edge. Accurate measurements have been made of the radiative heat transfer, the pillar conduction and the gas conduction using a guarded hot plate apparatus. Vacuum glazing is found to have low thermal conductance roughly below $1W/m^2K$. Among the heat transfer modes of residual gas conduction, conduction through support pillar and the radiative heat transfer between the glass panes, the last one is the most dominant to the overall thermal conductance. Vacuum glazing using very low emittance AI-coated glass has an overall thermal conductance of about $0.7W/m^2K$.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.930-936
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• 2004

Wogonin (5,7-dihydroxy-8-methoxyflavone), an active component originated from the root of Scutellaria baicalensis Georgi, has been reported to possess antioxidant and anti-inflamma-tory properties. In this study, we investigated the neuroprotective effect of wogonin in a focal cerebral ischemia rat model. Wogonin markedly reduced the infarct volume after 2 h middle cerebral artery occlusion followed by 22 h reperfusion. Wogonin decreased the production of nitric oxide and inflammatory cytokines such as TNF-$\alpha$ and IL-6 in lipopolisaccharide-stimu-lated microglial cells. While wogonin reduced the activity of NF-$textsc{k}$B, it did not change the activ-ity of mitogen-activated protein kinases family members, p38, ERK and JNK. The lipopolisaccharide-stimulated production of NO and cytokines was significantly blocked by vari-ous kinds of NF-$textsc{k}$B inhibitors such as N-acetyl cysteine, pyrrolidinedithiocarbamate and MG-132. The data may indicate that wogonin has neuroprotective effect by preventing the over-activation of microglial cells, possibly by inactivating NF-$textsc{k}$B signaling pathway

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.10
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• pp.962-967
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• 2004

A bogie is the device that connects a car body and wheel sets of a rail vehicle. It is the critical component that determine:; the running safety, The bogie consists of a frame, suspensions, brakes and wheel sets. Various analyses including a numerical simulation using a finite element method, a static load test, a fatigue test, ai)d r running test should be carried out to design the bogie. However cracks have been found at some end beams of the bogies mounted on the freight cars running with the high speed. The cracks of the end beam results in deterioration of the brake performance an the running safety, A new design has been suggested to solve this problem by ROTEM company and it's performance has been tested in this paper. Numerical simulations and dynamic tests are carried out to figure out the causes of cracks in the conventional bogie, and the vibrational characteristics of the improved bogie are compared with those of the conventional one.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.3
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• pp.77-80
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• 2003

An innovative ozonizer has been developed using a high frequency, surface discharge and a high purity Ti-Si-AI ceramic catalyst as a dielectric component. Using a type of thin film, a thin cylindrical compound ceramic catalyst layer was adhered to the outside surface of its inner electrode. An alternating current (AC) exciting voltage with frequencies from 0.6 KHz to 1.0 KHz and peak-to-peak voltages of 4-6 ㎸ was applied between the electrodes to produce a stable high-frequency silent discharge. A substantial reduction of the exciting voltage was also enabled by means of a thin Ti-Si-Al ceramic catalyst tube. As a result, the ozonizer can effortlessly obtain the required ozone concentration (50-60 g/$m^2$ for oxygen) and high ozone efficiency consumption power (180 g/kWh for oxygen) with-out the assistance of any particular methods. For purposes of this experiment, oxygen gas temperature was set at 2$0^{\circ}C$, with an inner reactor pressure of 1.6 atm at 600 Hz and a flow rate of 2 l/min.

• International Journal of Advanced Culture Technology
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• v.7 no.3
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• pp.143-148
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• 2019

In order to solve the urban problems caused by the increase of the urban population, the construction of smart city applying the latest technology is being carried out all over the world. In particular, we will create a smart city platform that utilizes data generated in the city to collect and store and analyze, thereby enhancing the city's continuous competitiveness and resilience and enhancing the quality of life of citizens. However, existing smart city platforms are not enough to construct a platform for smart city as a platform for solution elements such as IoT platform, big data platform, and AI platform. To complement this, we will reanalyze the existing overseas smart city platform and IoT platform in a comprehensive manner, combine the technical elements applied to it, and apply it to the future Korean smart city platform. This paper aims to investigate the trends of smart city platforms used in domestic and foreign countries and analyze the technology applied to smart city to study smart city platforms that solve various problems of the city such as environment, energy, safety, traffic, environment.

• Imaging Science in Dentistry
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• v.49 no.1
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• pp.1-7
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• 2019

Purpose: Artificial intelligence (AI), represented by deep learning, can be used for real-life problems and is applied across all sectors of society including medical and dental field. The purpose of this study is to review articles about deep learning that were applied to the field of oral and maxillofacial radiology. Materials and Methods: A systematic review was performed using Pubmed, Scopus, and IEEE explore databases to identify articles using deep learning in English literature. The variables from 25 articles included network architecture, number of training data, evaluation result, pros and cons, study object and imaging modality. Results: Convolutional Neural network (CNN) was used as a main network component. The number of published paper and training datasets tended to increase, dealing with various field of dentistry. Conclusion: Dental public datasets need to be constructed and data standardization is necessary for clinical application of deep learning in dental field.

• Wind and Structures
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• v.38 no.1
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• pp.75-91
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• 2024

Reliable wind signal reconstruction can be beneficial to the operational safety of long-span bridges. Non-Gaussian characteristics of wind signals make the reconstruction process challenging. In this paper, non-Gaussian wind signals are converted into a combined prediction of two kinds of features, actual wind speeds and wind angles of attack. First, two decomposition techniques, empirical mode decomposition (EMD) and variational mode decomposition (VMD), are introduced to decompose wind signals into intrinsic mode functions (IMFs) to reduce the randomness of wind signals. Their principles and applicability are also discussed. Then, four artificial intelligence (AI) algorithms are utilized for wind signal reconstruction by combining the particle swarm optimization (PSO) algorithm with back propagation neural network (BPNN), support vector regression (SVR), long short-term memory (LSTM) and bidirectional long short-term memory (Bi-LSTM), respectively. Measured wind signals from a bridge site in a deep-cutting gorge are taken as experimental subjects. The results showed that the reconstruction error of high-frequency components of EMD is too large. On the contrary, VMD fully extracts the multiscale rules of the signal, reduces the component complexity. The combination of VMD-PSO-Bi-LSTM is demonstrated to be the most effective among all hybrid models.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.124-128
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• 2000

This study was designed to investigate the effects of sea tangle(Laminaria japonica) extract (Dasi-Ex group: dry base $4.0{\%}$) and fucoidan-added (Fuco-I, II, III group: fucoidan of $1.0{\%}, 2.0{\%}, 3.0{\%}$ added to Dasi-EX) drinks on lipid metabolism of stressed mice. ICR male mice ($20 {\pm} 2 g$) were fed experimental diets and given free through water bottle filled with these beverages instead of water for 18 days including sociopsychological stress of 4 days. Dasi-Ex and Fuco-I, II, III groups resulted in slight decreases $3{\$}$ in body weight gain and $6{\~}12{\%}$ in feed and gross efficiencies compared with control groups. Serum protein contents were slightly increased $1{\~}5{\%}$ by administrations of these beverages compared with control group, reflecting inhibitory effect of sociopsychological stress by increase of protein levels. Significant differences in serum cholesterol contents of Dasi-Ex and Fuco-I groups could not be obtained, but Fuco-II and III groups resulted in marked decreases ($13{\~}17{\%}$) in serum cholesterol contents compared with control group. LDL-cholesterol contents resulted in marked decreases ($about 20 and 25{\%}$, respectively) in Fuco-II and III groups, whereas HDL-cholesterol content was significantly increases ($about 16{\%}$) in Fuco-III group compared with control group. Fuco-I, II and III groups resulted in a marked decreases ($15{\%}, 20{\%} and 40{\%}$, respectively) in atherogenic index (AI) compared with control group. Significant differences in serum lipid peroxide (LPO) contents of Dasi-Ex and Fuco-I groups could not be obtained, but Fuco-II and III groups resulted in a significant decrease about $10{\%}$ in serum LPO contents compared with control group. These results suggested that fucoidan drinks added sea tangle could significantly inhibited chronic degenerative diseases by improvement of effective lipid metabolism or fucoidan component.