• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.5
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• pp.66-74
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• 2002

OFDM(Orthogonal Frequency Division Multiplexing)is a one of the nst promising digital modulation techniques adapted for Digital audio broadcasting or Digital TV since it is very robust against multipath fading channels. From 1997, since the OFDM technique was considered as the physical layer standard for the high data rate wireless LAN systems in the 5㎓ band, related studies have been studied actively. The key element to implement high data rate wireless LAN system using OFDM technique are IFFT and FFT modules. In this paper, new IFFT and FFT module are designed and implemented using current cut circuit based on the matrix-rounding process for the low-power consumptive operation and high-speed data processing. In addition to, we certify the available operation of the rounded IFFT/FFT module in the AWGN channel by using the BER performance simulation of IEEE 802.11TGa based OFDM modem with rounded IFFT/FFT module.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1090-1095
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• 1999

In order to minimize the occurrence of fatty liver, this study investigated how adding a high level of dietary choline or methionine affected the lipid metabolism of Tsaiya ducks. Feeding trials were conducted with sixty Tsaiya ducks during their growing period, when they were 8-12 weeks old, and during their laying period, 10-14 weeks after the onset of laying when they were 26-30 weeks old. The ducks were randomly assigned to one of three groups: a control group (basal diet), a group in which methionine was added to the basal diet, and a group in which choline was added to the basal diet. The levels of methionine and choline added were twice as high as the levels recommended by the NRC for layer-type chickens. Experimental results indicated that adding choline to the basal diet of growing ducks significantly (p<0.05) increased their body weight, while adding methionine significantly (p<0.05)reduced their body weight. Adding either choline or methionine reduced the ducks' liver fat content in both the growing and the laying periods (p<0.05). Ducks receiving added methionine or choline in their diets displayed enhanced egg production (p<0.05). Adding choline increased serum triacylglycerol (TG) in the laying period (p<0.05). Adding either choline or methionine did not significantly (p>0.05) affect the t-globulin level. Adding methionine increased the activity of liver malic dehydrogenase in both the growing and the laying periods, and increased fatty acid synthetase in the laying period (p<0.05). While adding choline markedly (p>0.05) increased VLDL and apo B in both the growing and the laying periods, it decreased HDL and apo A in the laying period (p<0.05). This study found that adding a high level of choline to the basal diets of Tsaiya ducks in both the growing and the laying periods had beneficial effects. Furthermore, adding methionine affected the lipid metabolism of Tsaiya ducks to a lesser extent than adding choline.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2002.11a
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• pp.132-132
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• 2002

Mostly, hypercholesterolemia has been focused on atherosclerosis and coronary heart disease and can be produced by intake of high cholesterol diet. However, toxic effects of cholesterol itself on liver and relationship between intake of high cholesterol diet and hepatic fibrosis have not been clearly investigated. Male Wistar rats were fed diet supplemented with 1.0 ％ cholesterol and 0.3 ％ sodium cholate for 12 weeks. Rats were sacrificed at 0, 3, 6, 9 and 12, respectively. Histopathological and blood chemical studies were performed on these animal sets. Total cholesterol, AST, ALT and LDH levels increased from week 3 and maintained around that level throughout the experiment compared to control. However, TG and albumin levels were the same or lower than those of control. Intake of high cholesterol and sodium cholate diet caused hepatic necrosis, macrophage infiltration, steatosis and fibrosis. Following feeding this diet to rats, hepatic necrosis, macrophage infiltration and steatosis markedly increased throughout the experiment, comparing to control. Collagen deposition and myofibroblasts were detected from at week 9 to 12 in the liver. Mast cell increased in proportion to the degree of hepatic damages. In conclusion, these results suggest that intake of high cholesterol diet is a risk factor on hepatic steatosis and fibrosis as well as atherosclerosis and coronary heart disease. Furthermore, this animal model for hepatic fibrosis can be use for application of anti-fibrogenic agents screening in vivo.

• Journal of the Korean Ceramic Society
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• v.44 no.6 s.301
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• pp.325-330
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• 2007

High porous AlO(OH) gel is used in precursor of ceramic material, coating material and porous catalyst. For use of these, not only physiochemical control for particle morphology, pore characteristic and peptization but also studies of synthetic method for preparation of high porous AlO(OH) gel were required. In this study, high porous AlO(OH) gel was prepared through the aging and filtration process of aluminum hydroxides gel precipitated by the hydrolysis reaction of $Na_2CO_3$ solution and $Al_2(SO_4)_3$ and $Na_2SO_4$ mixed solution. In this process, optimum synthetic condition of AlO(OH) gel having excellent pore volume as studying the effect of hydrolysis pH on gel precipitates has been studied. Hydrolysis pH brought about numerous changes on crystal morphology, surface area, pore volume and pore size. Physiochemical properties of gel were investigated as using XRD, TEM, TG/DTA, FT-IR and $N_2$ BET method.

• The Korea Journal of Herbology
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• v.30 no.6
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• pp.83-91
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• 2015

Objectives : The present study was conducted to examine whether Cynanchi wilfordii radix (CWR) with or without fermentation has an ameliorative effect on hyperlipidemia in rats.Methods : We analyzed the contents of Conduritol F on Cynanchi wilfordii radix. The experimental animals were divided into six groups; normal diet fed group (N), high cholesterol fed control group (Con), Lovastatin 20 mg/kg (L), CWR-W 300 mg/kg (CWR-W), and CWR-F 300 mg/kg on hyperlipidemia model induced by feeding 1.25% cholesterol. Rats were administrated orally every day for 8 weeks. And lipid profile of serum and weight change were observed.Results : The vehicle displayed a markedly increased body weight and significantly increased liver and epididymal fat weight, however, the administration of CWR improved the body, liver, and epididymal fat weights. All drug treatment reduced significantly the serum level of total cholesterol and LDL-cholesterol elevated by intake of high cholesterol diet. TG displayed a reducing tendency all drug treatment, however, CWR-W decreased significantly. Atherogenic index and cardiac risk factor increased high cholesterol diet fed control group, while the administration of CWR-W and CWR-F decreased significantly. The major index of liver injury such as AST and ALT improved in all drug treatment.Conclusions : These results suggest that CWR extended the effect of lipid enhanced. Therefore CWR with or without fermentation may be useful for therapeutic treatment of clinical conditions associated with hyperlipidemia. Finally, these require more investigations about the action mechanism of CWR in the future.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.259-264
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• 2004

Baek-kimchi (whitish baechu kimchi) was evaluated for anti-obesity properties and effects on triglyceride (TG) and cholesterol in blood and adipose tissues in rats fed a high fat (20 %) diet, and compared to the similar effects of baechu kimchi. Baek-kimchi does not use red pepper powder but contains higher levels of sliced radish and pear than baechu kimchi. SD rats were raised for four weeks on either a normal diet (ND, based on the AIN-93M diet), high fat diet (HFD, supplemented with 16% lard oil in the ND), or HFD containing 5 % baek-kimchi or 5 % baechu kimchi. Feed consumption was not different among the groups, but weight gains were significantly lower in the groups fed either the normal diet or HFD with baek-kimchi or baechu kimchi diets than the group fed HFD alone. The weights of liver and epididymal and perirenal fat pads in baek-kimchi and baechu kimchi diet groups were lower than those of the HFD groups, but the baek-kimchi diet group had lower epididymal and perirenal fat pad weights than the baechu kimchi diet group (p<0.05). The baechu kimchi dietary group also had significantly lower triglyceride and cholesterol contents in liver and epididymal and perirenal fat, reversing the higher levels seen in HFD. Baek-kimchi and baechu kimchi diets were also effective in lowering serum triglyceride and cholesterol levels (p<0.05). These results suggest that baek-kimchi and baechu kimchi consumption can reverse the effects of HFD on weight gain and blood and tissue lipids, and that baek-kimchi is more effective than baechu kimchi. The greater effect is probably due to the higher content of radish and pear used in baek-kimchi.

• The Journal of Internal Korean Medicine
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• v.40 no.3
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• pp.356-368
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• 2019

Objectives: This study was designed to evaluate the efficacy of Pharbitidis Semen (PS) on obesity using 3T3-L1 cells and high-fat-diet rats. Methods: After the administration of PS at a concentration of 0.125, 0.25, and 0.50 mg/ml in 3T3-L1 cells, the degree of differentiation of adipocytes was measured by Oil Red O staining. The experimental animals were divided into five groups in vivo. Normal group: diet-fed normal group (Normal), Control group (Control): high-fat-diet (HFD)-fed, Positive control group (PC): HFD+Contrave 200 mg/kg, PS_Low group: HFD+PS 250 mg/kg group, PS_High group: HFD+PS 500 mg/kg. Results: The total cholesterol, low density lipoprotein-cholesterol (LDL-cholesterol), and triglycerides (TG) content of the PS medication groups were significantly lower than those of the control group. In addition, high density lipoprotein cholesterol (HDL-cholesterol) tended to increase, and free fatty acid, total lipid, and phospholipid tended to decrease, but the decrease was not statistically significant. The administration of PS inhibited the differentiation of 3T3-L1 adipocytes, and a statistically significant difference was found in the group administered with 0.125 mg/ml. The mRNA expression of $PPAR-{\gamma}$ and leptin, which are involved in the differentiation of adipocytes, was observed using reverse transcription polymerase chain reaction (RT-PCR). The expressions of $PPAR-{\gamma}$ and leptin significantly decreased in comparison with the control and the positive control.

• Biomedical Science Letters
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• v.25 no.3
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• pp.227-236
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• 2019

In this study, the anti-oxidant, anti-inflammatory, and anti-obesity activities of an ethanol extracts of Ulmus divididiana var. japonica (UDE) were investigated in vitro and in vivo. UDE anti-oxidant activity was evaluated with an Electron Spin Resonance (ESR) spectrometer, which measured 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity. Cell viabilities were estimated using 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay. LPS-stimulated BV-2 microglia were used to study the production of nitric oxide (NO). Cells stimulated with LPS produce more NO than normal control cells. However, cells treated with the UDE decreased this production in a concentration dependent manner (100, 250, 500, $1,000{\mu}g/mL$). Also, we investigated the anti-obese activity of UDE in SD rats. The SD rats were randomly divided into five groups: 10% low fat diet (N), 45% high fat diet (H), 45% high fat diet + garcinia extracts 200 mg/kg/day (HG200), high fat diet + UDE 200 mg/kg/day (HU200), high fat diet + UDE 400 mg/kg/day (HU400). UDE was found to lower whole body and abdominal and epididymal adipose tissue weights and lowered plasma levels of triglyceride (TG), compared to those in H group. Histological analyses of the liver and fat tissues of rat treated with UDE revealed significantly decreased number of lipid droplets and decreased size of adipocytes compared to the H group. These results suggest that UDE might be used to develop potent anti-oxidant, anti-inflammatory, and anti-obesity agents, and may be useful as ingredients for related new functional raw materials.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.220-225
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• 2022

Perlite is one of the major constituents of the radioactive thermal insulation waste (RTIW) originating from nuclear power plants and, for proper waste management, a significant reduction in its volume is required prior to disposal. In this work, the volume reduction of perlite is studied by high-temperature treatment method with using K₂CO₃ as a flux. The perlite is ground with 0-30 wt% K₂CO₃, and differential thermal analysis/thermogravimetric analysis is used to monitor the glass transition temperature (T_g) and weight loss. The Tg varied between ~772.2 and 837.1 ℃ with the minima at ~643.5 ℃ with the addition of ~10 wt% K₂CO₃. It is observed that compared to the pure perlite the volume reduction ratio (VRR) increases with the addition of K₂CO₃. The VRR of 11.20 is observed with 5 wt% K₂CO₃ at 700 ℃, as compared to VRR of 5.56 without K₂CO₃ at 700 ℃. The X-ray photoelectron spectroscopy and scanning electron microscopy are used to characterize perlite samples heat-treated without/with 5 wt% K₂CO₃ at 700 ℃. Moreover, the atomic absorption spectroscopy indicates that the proposed heat-treatment procedure is able to completely retain the radionuclides present in the perlite RTIW.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1043-1053
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• 2013

We investigated the ability of soybean curd residue (SCR) and its fermented products to inhibit obesity and improve the blood lipid profiles of obese mice fed a high-fat diet. Samples were prepared by fermenting SCR with Aspergillus oryzae var effuses KACC 44990 (ASCR), a microbe used for the fermentation of traditional Korean Meju, and with Monascus pilosus IFO 4480 (MSCR), a microbe used for the production of red rice. In addition, AMSCR, a mixture composed of equal amounts of ASCR and MSCR, was also prepared. Male mice were divided into six groups and fed with either a normal diet, a high-fat diet, or a high-fat diet supplemented with SCR, ASCR, MSCR, or AMSCR. After 8 weeks, body weight gain, serum and hepatic lipid profiles, and the activities of enzymes that generate or scavenge reactive oxygen species (ROS) were evaluated. Compared with the high-fat diet group, all the test groups showed a significant reduction in body, organ, and epididymal fat weight gain. These effects were observed with supplements in the order AMSCR>ASCR>MSCR>SCR. Similarly, supplements of test samples reduced high levels of serum and hepatic triglycerides (TG), total cholesterol, and low-density lipoprotein (LDL) cholesterol caused by hight-fat diet, while high-density lipoprotein (HDL) cholesterol was increased. Interestingly, the ability of ASCR to lower serum TG was stronger than that of MSCR, while MSCR showed a stronger hypocholesterolemic effect than ASCR. Meanwhile, AMSCR returned comprehensively serum lipid levels to normal. In addition, hepatic damage was prevented with effects in the order AMSCR>ASCR>MSCR>SCR. Hepatic ROS generating system including xanthine oxidase (XO) and ROS scavenging system including superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione S-transferase (GST) were recovered to normal level by all test diets. In conclusion, this study suggests that SCR and its fermented products can inhibit obesity and improve lipid profiles.