• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.73-81
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• 1998

Pregnant Sprague-Dawley rats were administered with Q-35 at the dose levels of 0, 30, 100 and 300 mg/kg/day by oral gavage from gestation day 17 to lactation period. Effects of the test chemical on general findings, reproductive performance of dams and development of Fl generation were examined. There were no treatment related changes in physical signs, body weight, necropsy findings, organ weights, delivery and nursing behavior. In 100 and 300 mg/fg/day treated groups, the food consumption of dams was decreased significantly during gestational day 19~21. The gestation length of 300 mg/tg/day treated group was increased significantly compared to the control group (22.3 $\pm$0.48 vs 22.0$\pm$0.39). Although the gestational length of all groups were in normal range of the rat, potential effect of the drug could not be ruled out. External anomaly of Fl fetus induced by Q-35 was not detected in any groups. There were no treaoent related changes in physical development, reflex functions, sensory functions, locomotor activity and motor coordinating activity. Estrus cycle, fertility and reproductive performance of Fl were not changed in all treated groups. There was no external abnormality related to the drug administration on the examination of F2. These results suggest that Q-35 has no adverse effect on the peri- and postnatal period in rats except the reduction of food consumption at the beginning of drug administration and the potential effect on the elongation of gestation length.

• Journal of Power Electronics
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• v.11 no.2
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• pp.194-201
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• 2011

The air flow supplied to a fuel cell system is one of the most significant factors in determining fuel efficiency. The conventional method of controlling the air flow is to fix the oxygen supply at an estimated constant rate for optimal efficiency. However, the actual optimal point can deviated from the pre-set value due to temperature, load conditions and so on. In this paper, the maximum efficiency point tracking (MEPT) algorithm is proposed for finding the optimal air supply rate in real time to maximize the net-power generation of fuel cell systems. The fixed step MEPT algorithm has slow dynamics, thus it affects the overall efficiency. As a result, the variable step MEPT algorithm is proposed to compensate for this problem instead of a fixed one. The complete small signal model of a PEM Fuel cell system is developed to perform a stability analysis and to present a design guideline. For a design example, a 1kW PEM fuel cell system with a DSP 56F807 (Motorola Inc) was built and tested using the proposed MEPT algorithm. This control algorithm is very effective for a soft current change load like a grid connected system or a hybrid electric vehicle system with a secondary energy source.

• Journal of Environmental Impact Assessment
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• v.15 no.6
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• pp.373-383
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• 2006

The spatial mapping of risk is very useful data in planning for disaster preparedness. This research presents a methodology for making the landslide life risk map in the Boeun area which had considerable landslide damage following heavy rain in August, 1998. We have developed a three-stage procedure in spatial data analysis not only to estimate the probability of the occurrence of the natural hazardous events but also to evaluate the uncertainty of the estimators of that probability. The three-stage procedure consists of: (i)construction of a hazard prediction map of "future" hazardous events; (ii) validation of prediction results and estimation of the probability of occurrence for each predicted hazard level; and (iii) generation of risk maps with the introduction of human life factors representing assumed or established vulnerability levels by combining the prediction map in the first stage and the estimated probabilities in the second stage with human life data. The significance of the landslide susceptibility map was evaluated by computing a prediction rate curve. It is used that the Bayesian prediction model and the case study results (the landslide susceptibility map and prediction rate curve) can be prepared for prevention of future landslide life risk map. Data from the Bayesian model-based landslide susceptibility map and prediction ratio curves were used together with human rife data to draft future landslide life risk maps. Results reveal that individual pixels had low risks, but the total risk death toll was estimated at 3.14 people. In particular, the dangerous areas involving an estimated 1/100 people were shown to have the highest risk among all research-target areas. Three people were killed in this area when landslides occurred in 1998. Thus, this risk map can deliver factual damage situation prediction to policy decision-makers, and subsequently can be used as useful data in preventing disasters. In particular, drafting of maps on landslide risk in various steps will enable one to forecast the occurrence of disasters.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.197-205
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• 2017

We investigate the slat noise generation mechanism by using large-eddy simulation (LES) and simple source modeling based on linearized Euler equations. An incompressible LES of an MD 30P30N three-element airfoil in the high-lift configuration is conducted at $Re_c=1.7{\times}10^6$. Using the total derivative of the hydrodynamic pressure (DP/Dt) acquired from the incompressible LES, representative noise sources in the slat cove region are characterized in terms of simple sources such as frequency-specific monopoles and dipoles. Acoustic radiation around the 30P30N multi-element airfoil is effectively computed using the Brinkman penalization method incorporated with the linearized Euler equation. The directivity pattern of $p^{\prime}_{rms}$ at $r=20c_{slat}$ in the multiple sources is closely compared to that obtained by the application of the LES/Ffowcs-Williams and Hawking's methods to the entire flow field. The power spectrum of p' at ${\theta}=290^{\circ}$ is in good agreement with the data reported in BANC-III, especially the broadband part of the spectrum with a decaying slope ${\propto}f^{-3}$.

• Molecules and Cells
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• v.37 no.2
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• pp.149-160
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• 2014

Plant breeders have focused on improving plant architecture as an effective means to increase crop yield. Here, we identify the main-effect quantitative trait loci (QTLs) for plant shape-related traits in rice (Oryza sativa) and find candidate genes by applying whole genome re-sequencing of two parental cultivars using next-generation sequencing. To identify QTLs influencing plant shape, we analyzed six traits: plant height, tiller number, panicle diameter, panicle length, flag leaf length, and flag leaf width. We performed QTL analysis with 178 $F_7$ recombinant inbred lines (RILs) from a cross of japonica rice line 'SNU-SG1' and indica rice line 'Milyang23'. Using 131 molecular markers, including 28 insertion/deletion markers, we identified 11 main- and 16 minor-effect QTLs for the six traits with a threshold LOD value > 2.8. Our sequence analysis identified fifty-four candidate genes for the main-effect QTLs. By further comparison of coding sequences and meta-expression profiles between japonica and indica rice varieties, we finally chose 15 strong candidate genes for the 11 main-effect QTLs. Our study shows that the whole-genome sequence data substantially enhanced the efficiency of polymorphic marker development for QTL fine-mapping and the identification of possible candidate genes. This yields useful genetic resources for breeding high-yielding rice cultivars with improved plant architecture.

• Herbal Formula Science
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• v.10 no.2
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• pp.127-141
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• 2002

Objectives: Haeganjeon(HGJ) has been used for the treatment of liver disease in traditional medicine. The present study was carried out to evaluate the antioxidant and protective effects of HGJ extract on oxidative damage of hepatocytes by tert-butyl hydroperoxide(t-BHP). Methods: In the linoleic acid water-alcohol system, the levels of lipid peroxide(LPO) were determined by TBA method. The scavenging effect of HGJ on ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$(DPPH) radical was determined according to the method of Hatano. In the Fenton system(ferrous ion reaction with hydrogen peroxide), the levels of hydroxyl radical induced LPO in rat liver homogenate were determined according to the method of TBA. Inhibitory effect of HGJ on superoxide generation was measured by xanthine-xanthine oxidase system. In order to evaluate antioxidative activity of HGJ in the liver cell, cultured normal rat liver cells(Ac2F) were prepared and incubated with or without HGJ. After 18hr, cells placed in DMEM medium without serum, and then incubated with 1mM tert-butyl hydroperoxide(t-BHP) for 2hrs. Viable cells were detected by MTT assay. Conclusions: In the linoleic acid autoxidation system, HGJ extract significantly inhibited the time course of the lipid peroxidation. These effects were similar to those of BHA HGJ extracts showed about 70% scavenging effect on DPPH radical. And HGJ extract inhibited the lipid peroxide formation in rat liver homogenate induced by hydroxyl radical derived from Fenton system. In addition, HGJ extract protected the cell death induced by t-BHP and significantly increased cell viability in the normal rat liver cell. These result indicated that HGJ extract might playa protective role against oxidative hepatic cell injury by means of free radical scavenger.

• International Journal of High-Rise Buildings
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• v.7 no.2
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• pp.145-151
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• 2018

Newly-designed high-rise buildings, both in China and abroad, have demonstrated new innovations from the creative concept to the creative method. from the creative concept to the creative method. At the same time, digital technology has enabled more design freedom in the vertical dimension. "Twisting" has gradually become the morphological choice of many city landmark buildings in recent years. The form seems more likely to be driven by the interaction of aesthetics and structural engineering. Environmental performance is often a secondary consideration; it is typically not simulated until the evaluation phase. Based on the research results of "DigitalFUTURE Shanghai 2017 Workshop - Wind Tunnel Visualization", an approach that can be employed by architects to design environmental-performance buildings during the early stages has been explored. The integration of a dynamic form-finding approach (DFFA) and programming transforms the complex relationship between architecture and environment into a dialogue of computer language and dynamic models. It allows the design to focus on the relationship between morphology and the surrounding environment, and is not limited to the envelope form itself. This new concept of DFFA in this research consists of three elements: 1) architectural form; 2) integration of wind tunnel and dynamic models; and 3) environmental response. The concept of wind tunnel testing integrated with a dynamic model fundamentally abandons the functional definition of the traditional static environment simulation analysis. Instead it is driven by integral environmental performance as the basic starting point of morphological generation.

• Journal of the Korean Society of Combustion
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• v.19 no.3
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• pp.1-7
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• 2014

Experimental study has been carried out to understand combustion characteristics of a swirl-stabilized premixed gas turbine combustor for power generation. $NO_x$ and CO emissions, extinction limit, pressure loss, and temperature distribution were measured for various operating conditions. Results show that, with increasing inlet air temperature, $NO_x$ is increased due to a higher adiabatic flame temperature while CO is increased or decreased for low or high A/F ratio regime, respectively. depending on the flame location. With decreasing load from the design condition, $NO_x$ is decreased as thermal load is reduced. With further decreasing load, however, $NO_x$ is increased due to a longer residence time. CO is decreased and then increased with decreasing load. Flame extinction limit is extended with increasing inlet air temperature as the recirculation strength is enhanced.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.162-170
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• 2007

Currently, due to the serious world-wide air pollution by substances emitted from vehicles, emission control is enforced more firmly and it is expected that the regulation requirements for emission will become more severe. Anew concept combustion technology that can reduce the NOx and PM in relation to combustion is urgently required. Due to such social requirement, technologically advanced countries are making efforts to develop an environment-friendly vehicle engine at the nation-wide level in order to respond to the reinforced emission control. As a core combustion technology among new combustion technologies for the next generation engine, the homogeneous charge compression ignition (HCCI) is expanding its application range by adopting multiple combustion mode, catalyst, direct fuel injection and partially premixed combustion. This study used a 2-staged injection method in order to apply the HCCI combustion method without significantly altering engine specifications in the aspect of multiple combustion mode and practicality by referring to the results of studies on the HCCI engine. And it is investigated that the effects of the engine rpm and load(or A/F) to emission characteristics.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.9-15
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• 1986

Interspecific hybrids of Pleurotus ostreatus and Pleurotus florida were formed by using protoplasts of complementing auxotrophs. The genetic markers were shown to segregate and recombine in the first generation of monosporus isolates from basidiocarp of seven fusion products. The analysis provides proof of heterokaryosis and strong evidence for haploidy of vegetative nuclei, a sexual cycle consisting of nuclear fusion and meiosis. In all the crosses there was no evidence of linkage between the genetic markers. Clamp connections were formed in monosporus mycelia from basidiocarp of fusion products.