• Speech Sciences
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• v.12 no.4
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• pp.31-42
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• 2005

Recently, Gaussian Mixture Model (GMM), a special form of CHMM, has been applied to speaker identification and it has proved that performance of GMM is better than CHMM. Therefore, in this paper the speaker models based on GMM and a new GMM using the modified EM algorithm are introduced and evaluated for text-independent speaker identification. Various experiments were performed to evaluate identification performance of two algorithms. As a result of the experiments, the GMM speaker model attained 94.6% identification accuracy using 40 seconds of training data and 32 mixtures and 97.8% accuracy using 80 seconds of training data and 64 mixtures. On the other hand, the new GMM speaker model achieved 95.0% identification accuracy using 40 seconds of training data and 32 mixtures and 98.2% accuracy using 80 seconds of training data and 64 mixtures. It shows that the new GMM speaker identification performance is better than the GMM speaker identification performance.

• Structural Engineering and Mechanics
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• v.8 no.3
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• pp.273-283
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• 1999

Two physical experiments are performed to verify the effectiveness of beam-particle model for simulating the progressive failure of particulate composites such as sandstone and concrete. In the numerical model, the material is schematized at the meso-level as an assembly of discrete, interacting particles which are linked through a network of brittle breaking beams. The uniaxial compressive tests of cubic and parallelepipedal specimens made of carbon steel rod assembly which are glued together by a mixture are represented. The crack patterns and load-displacement response observed in the experiments are in good agreement with the numerical results. In the application respect of beam-particle model to the particulate composites, the influence of defects, particle arrangement and boundary conditions on crack propagation is approached, and the correlation existing between the cracking evolution and the level of loads imposed on the specimen is characterized by fractal dimensions.

• Journal of Nutrition and Health
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• v.48 no.1
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• pp.19-29
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• 2015

Purpose: To investigate the effects of the intake of xylooligosaccharide-sugar mixture (XOS) on defecation frequency and symptoms in 56 young women (mean age of 22.1 years old) with constipation. Methods: Two experiments were conducted. In experiment 1, a randomized double-blind study was performed to evaluate the effect of 6 weeks' intake of 10 g sucrose containing 7% xylooligosaccharide or 10 g sucrose on constipation. In experiment 2, 24 g coffee mixture containing 12.8 g plant cream and 11.2 g xylooligosaccharide-sugar mixture was consumed by the subjects. During the study, the clinical efficacy was assessed by using a daily diary. The subjects indicated the number of frequencies they defecated in a day and the clinical symptom scores. Results: In experiment 1, the mean frequency of defecations was 2.07 in the pretreatment week and increased significantly to 4.05, 4.42, 4.84, 4.84, and 4.05 in weeks 2 to 6 of XOS intake, in comparison with the 3-3.67 with sucrose intake (sucrose, SUC). In experiment 2, the mean frequency of defecations significantly increased from 2.47 in the pretreatment week to 4.11-5.67 in weeks 1-6 of XOS intake. The occurrence of very loose or loose stools in the XOS group was significantly increased in weeks 5 and 6, compared with the pretreatment week and SUC group. XOS intake significantly alleviated the abdominal displeasure and feeling of residual stool leftness in weeks 2, 3, 5, and 6, while SUC did so in weeks 4 and 6 (p < 0.05). The coffee mixture containing xylooligosaccharide-sugar mixture reduced the abdominal displeasure and feeling of residual stool leftness from week 3 until the end of the experiment (p < 0.05). Conclusion: Our results suggest that xylooligosaccharide-sugar mixture intake was effective, without adverse effects, for the alleviation of constipation in the young women in this study.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.45-51
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• 2005

As a silicate source to rice, a coal ash (50%) was mixed with a phosphogypsum (hereafter, gypsum, 50%). Field experiments were carried out to evaluate rice (Oryza sativa) productivity in silt loam (SiL) to which 0, 20, 40 and $60Mg\;ha^{-1}$ of the mixture were added. The mixture increased rice yield and showed the highest yields following the addition of $30Mg\;ha^{-1}$. The mixture did not result in an excessive uptake of heavy metals by the rice grain. The mixture improved available silicate and phosphate and exchangeable calcium contents in soil. The available boron content in soil increased with the mixture application levels up to $1.42mg\;kg^{-1}$ following the application of $60Mg\;ha^{-1}$, but boron toxicity in rice was not found. It is concluded that the coal ash and gypsum mixture could be a good alternative to inorganic soil amendments to restore the soil nutrient balance in paddy soil.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.8-14
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• 2002

Cotinine, one of nicotine metabolites, has been blown to reduce 4-(methylnitro samino)-1-(3-pyridyl)-1-butanone(NNK)- induced $O^{6}$MeG DNA adducts significantly in A/J mice when administered together with NNK. In order to examine the effects of phyto-extract mixture on the conversion of cotinine from nicotine, cellular and clinical experiments were carried out. When the phyto-extract mixture was added to culture media, human liver cells (FLCFR5) produced cotinine from nicotine 2~3 times compared to the control. The phyto-extract mixture which was microinjected into Xenopus oocyte along with nicotine showed the almost similar production of cotinine compared with the results of hepatic cell culture. In clinical test employing 17 to 20 healthy men, concentrations of urinary cotinine derived from smoking after taking photo-extract mixture increased up to 2 times compared to the control group. These results indicatethat the phyto-extract mixture can increase the metabolic efficiency of nicotine to cotinine, leading to the reduced formation of $O^{6}$MeG DNA adducts.

• Journal of the Korean GEO-environmental Society
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• v.15 no.4
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• pp.13-27
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• 2014

Catchments soil erosion, one of the most serious problems in the mountainous environment of the world, consists of a complex phenomenon involving the detachment of individual soil particles from the soil mass and their transport, storage and overland flow of rainfall, and infiltration. Sediment size distribution during erosion processes appear to depend on many factors such as rainfall characteristics, vegetation cover, hydraulic flow, soil properties and slope. This study involved laboratory flume experiments carried out under simulated rainfall in a 3.0 m long ${\times}$ 0.8 m wide ${\times}$ 0.7 m deep flume, set at $17^{\circ}$ slope. Five experimental cases, consisting of twelve experiments using three different sediments with two different rainfall conditions, are reported. The experiments consisted of detailed observations of particle size distribution of the out-flow sediment. Sediment water mixture out-flow hydrograph and sediment mass out-flow rate over time, moisture profiles at different points within the soil domain, and seepage outflow were also reported. Moisture profiles, seepage outflow, and movement of overland flow were clearly found to be controlled by water retention function and hydraulic function of the soil. The difference of grain size distribution of original soil bed and the out-flow sediment was found to be insignificant in the cases of uniform sediment used experiments. However, in the cases of non-uniform sediment used experiments the outflow sediment was found to be coarser than the original soil domain. The results indicated that the sediment transport mechanism is the combination of particle segregation, suspension/saltation and rolling along the travel distance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.4
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• pp.334-340
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• 2003

This study was conducted to evaluate the effects of dietary herbal extracts mixture on the growth rate. carcass traits and serological changes in finishing pigs. For the Exp 1, eighty Duroc(Yorkshir(Landrace pigs(81.58$\pm$3.20kg average initial body weight) were used in a 45 day experiment. Dietary treatments included 1) NC(negative control; antibiotics-free diet), 2) PC(positive control; NC diet added 0.1% of chlortetracycline), 3) NCM(NC diet added 0.1% of herbal plant mixture) and 4) PCM(PC diet added 0.1% of herbal plant mixture). Through the entire experimental period, ADG of pigs fed NCM and PCM diets was greater(P<0.08) than that of pigs fed NC diet. There was interaction of ADG(P<0.01) in pigs fed NC diet with herbal plant mixture compared to pigs fed PC diet with herbal plant mixture. ADFI and G/F tended to increase in PC and NCM treatments. However, there were not significantly differences among the treatments. Total protein of serum was improved by supplementation of the herbal plant mixture in NC diet(P<0.04). For the Exp 2. one hundred Duroc(Yorkshir(Landrace pigs(77.36$\pm$2.01kg average initial body weight) were used in a 28 day experiment. Dietary treatments included 1) NC(negative control; antibiotics-free diet), 2) PC(positive control; NC diet added 0.1% of chlortetracycline), 3) PM0.1(NC diet added 0.1% of herbal plant mixture) and 4) PM0.2(NC diet added 0.2% of herbal plant mixture). Through the entire experimental period, ADG tended to increase in PC treatment. However, there was not significantly difference among the treatments. Carcass weight in NC was higher than other treatments(P<0.06). Backfat thickness was higher in pigs fed PC than other treatments. However, there was not significantly difference among the treatments. A grade appearances of carcass tended to increase in pigs fed PM(P<0.09). In conclusion, the results of the experiments suggest that pigs fed PM could be a beneficial growth performance and serogical immunity for finishing pigs.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.3
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• pp.63-71
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• 2006

A downdraft gasifier was made of stainless steel for biomass gasification. Internal reactor had a 300 mm diameter and 8 air intakes. Three thermocouples were installed to measure the temperature inside the reactor. Three different biomass fuels were provided in the experiments to find out the effects of fuel conditions on gasification processes; charcoals, woodchips, and mixture of woodchip and charcoals. Two different experiments were conducted fer charcoal experiments, small and larger sizes of charcoal fuels. It took about 10 minutes after ignition to generate combustible producer gas when charcoal was f9d, but 20 or more minutes for woodchips. When the gasification was stabilized, the highest temperature was observed just below the combustion zone. The air flow rate for woodchip experiment was provided at 25% of a stoichiometric requirement of combustion, which was within the range of typical air flow rate fer woody biomass gasification. Carbon monoxide concentrations were also within the values reported in the previous studies, ranging 20 to 30% depending on fuel types. It could be seen that fuel size and heating value were very important parameters in biomass gasification. These parameters should be taken into account in operating and designing biomass gasifiers.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.5
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• pp.502-507
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• 2015

In this study, a microscale drilling process was conducted to evaluate the cutting characteristics of functionally graded materials. A mixture of M2 and Cu powders were formed and sintered to produce disk specimens of various compositions. Subsequently, a microscale hole was created in the specimen by using a desktop-size micro-machining system. By using design of experiments and analysis of variance, it was found that the M2-Cu composition, spindle speed, and the interactions between these two factors had significant effects on the magnitude of cutting forces. However, the influence of feed rate on the cutting force was negligible. A mathematical model was established to predict the cutting force under a wide range of process conditions, and the reliability of the model was confirmed experimentally. In addition, it was observed that increasing the wt% of Cu in an M2-Cu specimen increased the high-frequency amplitude of cutting forces.

• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.346-351
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• 2024

Chemical reduction using catalysts and NaBH₄ presents a promising approach for reducing 4-nitrophenol contamination while generating valuable byproducts. Covalent organic frameworks (COFs) emerge as a versatile platform for supporting catalysts due to their unique properties, such as high surface area and tunable pore structures. This study employs design of experiments (DOE) to systematically optimize the synthesis of Cu embedded COF (Cu/COF) catalysts for the reduction of 4-nitrophenol. Through a series of experimental designs, including definitive screening, mixture method, and central composition design, the main synthesis parameters influencing Cu/COF formation are identified and optimized: MEL:TPA:DMSO = 0.31:0.36:0.33. Furthermore, the optimal synthesis temperature and time were predicted to be 195 ℃ and 14.7 h. Statistical analyses reveal significant factors affecting Cu/COF synthesis, facilitating the development of tailored nanostructures with enhanced catalytic performance. The catalytic efficacy of the optimized Cu/COF materials is evaluated in the reduction of 4-nitrophenol, demonstrating promising results in line with the predictions from DOE.