• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4205-4209
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• 2011

The $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ silicate was prepared by blending of $Li_2MnSiO_4$ and $Li_2FeSiO_4$ precursors with same molar ratio. The one of the silicates of $Li_2FeSiO_4$ is known as high capacitive up to ~330 mAh/g due to 2 mole electron exchange, and the other of $Li_2FeSiO_4$ has identical structure with $Li_2MnSiO_4$ and shows stable cycle with less capacity of ~170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than $LiFePO_4$). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The $Li_2Mn_{0.5}Fe_{0.5}SiO_4$/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63% of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in $Li_2Mn_{0.5}Fe_{0.5}SiO_4$. We have observed that $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50%) due to the accelerated structural degradation and related reaction.

• Korean Journal of Optics and Photonics
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• v.5 no.3
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• pp.423-430
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• 1994

We designed and fabricated the single mode fiber pigtailed DFB-LD module for 2.5 Gbps optical communication system. In the design of the DFB-LD module, we made the module divided into two parts of inner sub-module and outer 14-pin butterfly package and cylindrical shaped sub-module contain quasi confocal 2 lens system including optical isolator and electrical connection between these parts via hybrid substrate of bias T circuit. Laser welding was used to assemble the sub-module which requires accurate fixing between optical elements. The fabricated DFB-LD module showed optical coupling efficiency of 20% and - 3 dB small signal response of more than 2.6 GHz. We confirmed mechanical reliability of the module by temperature cycle test where the tested module exhibit optical power fluctuation of less than 10%. Finally we evaluated the performance of the fabricated DFB-LD module as light source of 2.5 Gbps optical communication system, sensitivity of - 30.2 dBm was obtained through 47 km optical fiber transmission under the criterion of $1\times10^{-10}$ BER and transmission penalties were 1.5 dB caused by extinction ratio and 1.0 dB caused by chromatic dispersion of normal single mode fiber. fiber.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.353-353
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• 2017

Rice yield of South Korea in 2015 was the highest of the last 30 years. It is important issue to establish food policy whether the historically highest yield in 2015 can be continued or just one-off event. Therefore, it is necessary to understand whether such a high yield as 2015 will be reoccurred. The aim of this study was to find out what climatic factor affect rice yield and how often these climatic factor could occur. For this study, the yield monitoring data from National Institute of Crop Science, Rural Development Administration and the meteorological data provided by Korea Meteorological Administration are used to identify the weather conditions could cause high yield, and how often these conditions occurred in the past. Our results indicated that such as high yield as 2015 could occur only when the mean sunshine hours of July and the mean sunshine hours from the end of August to early September was more than 5.1 hours and 6 hours, respectively. Mean sunshine hour of July may be related to grain number. The mean sunshine hour from the end of August to early September was presumed to relate to grain filling ratio. The relationship between monthly mean temperature and yield or yield component was not clear in this study. In this study, any cycle of high weather condition was not found. Therefore, the probability of high yield weather condition was expressed by frequency. The frequency of the sunshine hour, could make high yield, were 8/35 (23%) over the past 35 years. And the frequency of two years consecutive sunshine hour condition, which could cause high yield, was 1/35 (2.9%). The frequency of recurrence of sunshine hour making high yield within the next 5 years or 10 years after high yield weather condition were 4/35 (11.4%). After all, the high yield as much as yield of 2015 could not be one-off event. But it was not also consecutive event.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.619-625
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• 2017

In this study, the formation of hydroxyl radical and decomposition characteristics of bisphenol A (BPA) was investigated by quantifying hydrogen peroxide formed as a reaction by-product during the formation stage of hydroperoxyl radical. The direct oxidation reaction by ozone only decomposed BPA just like the Criegee mechanism under the condition where radical chain reactions did not occur. Non-selective oxidation reactions occurred under the conditions of pH 6.5 and 9.5 where radical chain reactions do occur, confirming indirectly the formation of hydroxyl radical. The decomposition efficiency of BPA by the added catalysts appeared in the order of $O_3$/PAC ${\geq}$ $O_3/H_2O_2$ > $O_3$/high pH > $O_3$ alone. 0.03~0.08 mM of hydrogen peroxide were continuously measured during the oxidation reactions of ozone/catalyst processes. In the case of $O_3$/high pH process, BPA was completely decomposed in 50 min of the oxidation reaction, but reaction intermediates formed by oxidation reaction were not oxidized sufficiently with 29% of the removal ratio for total organic carbon (TOC, selective oxidation reaction). In the case of $O_3/H_2O_2$ and $O_3$/PAC processes, BPA was completely decomposed in 40 min of the oxidation reaction, and reaction intermediates formed by the oxidation reaction were oxidized with 57% and 66% of removal ratios for TOC, respectively (non-selective oxidation reactions).

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.33-37
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• 2007

A 2 years old female beagle dog was examined because of the vaginal discharge and vaginal swelling at 7th day after mating. Abdominal ultrasonography revealed multiple follicular cysts on both ovaries. Also, the ratio of superficial cells was above 90% based on vaginal cytology. She was still in standing heat, with the tail deflected up and flagging when a male sniffed the vulva and attempted to mount. The dog was diagnosed with multiple follicular cysts by vaginal cytology, clinical signs and ultrasonography. The dog was treated with GnRH $50{\mu}g$ injection by intramuscularly. The sizes of the cysts were decreased two weeks after GnRH treatment, and then the dog delivered an offspring at 68th day after last mating. To confirm the stage of estrous cycle, we performed hormone analyses, retrospectively $Estradiol-17{\beta}$ concentration was 78pg/ml at diagnosis. Progesterone concentration was 6.9ng/ml at the last mating, and 66.9ng/ml at diagnosis. Therefore, we confirmed that follicular cysts was observed during diestrous stage in a beagle dog.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.7-16
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• 2004

The homogeneous road section is defined as one consisted of similar traffic characteristics focused on demand and supply. The criteria, in the aspect of demand, are the diverging rate and the ratio of green time to cycle time at signalized intersection, and distance between the signalized intersections. The criteria, in that or supply, are the traffic patterns such as traffic volume and its speed. In this study, the effective method to generate valuable data, pointing out the problems of removal method of obscure data, is proposed using data collected from Gonjiam IC to Jangji IC on the national highway No.3. Travel times are collected with licence matching method and traffic volume and speed are collected from detectors. Futhermore, the method of selecting homogeneous road section is proposed considering demand and supply aspect simultaneously. This method using outlier filtering algorithm can be applied to generate the travel time forecasting model and to revise the obscured of missing data transmitting from detectors. The point and link data collected at the same time on the rational highway can be used as a basis predicting the travel time and revising the obscured data in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.5
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• pp.23-35
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• 2011

The pedestrian green time is usually long at wide width intersections. This sometimes causes the increase of delay on the whole intersection because of long cycle length and thus small g/C ratio on some direction. In this paper, to improve these problems, staggered pedestrian crossing was evaluated on the vehicular and pedestrian aspects. The results were gained by using both TRANSYT-7F and VISSIM model. The vehicle control delay of the staggered pedestrian crossing was estimated to be decreasing than that of the general pedestrian crossing by 14.9% to 85.6%. The pedestrian average delay of two pedestrian crossing systems was examined by analytical method and VISSIM. According to the analytical method there was no significant difference between each pedestrian crossing system. The pedestrian delay of staggered pedestrian crossing was from 13.4% to 22.3% than the general pedestrian crossing by VISSIM. In conclusion, the staggered pedestrian crossing was more effective than general pedestrian crossing for both the vehicle and the pedestrian. However this conclusion was resulted from micro simulation where traffic volume condition, v/c, was from 0.8 to 1.1.

• Journal of IKEEE
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• v.22 no.3
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• pp.638-644
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• 2018

In this paper, we develop a measurement system that uses 3D Scintillator and NaI(TI) Detector to 3-dimensionally identify the location of multiple radiation sources in moving vehicle loads. The radiation measurement system consists of radiation measurement (plastic scintillator), 2-channel Pulse Counter Board, nuclide analysis (NaI(TI) detector) and 1 channel MCA Board. The source locator algorithm calculates the coordinate value of the ratio of the CPS value($1/r^2$) of the source according to the angle(${\theta}$) in inverse proportion to the square of the distance(X, Y) through the SVM classification. The coordinate values are input every predetermined period of the spectrum, and after analyzing the spectrum per unit cycle, the position of the nuclide at the time is calculated by determining whether or not the nuclide is present in the remaining part except for the background area. As a result of the position discrimination test, the error within the international standard of ${\pm}1m$ was shown. Thus, the utility of the proposed system has been demonstrated.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6159-6164
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• 2013

Background: Phytochemical compounds are emerging as a new generation of anticancer agents with limited toxicity in cancer patients. The purpose of this study was to investigate the potential effcts of thymoquinone, caffeic acid phenylester (CAPE) and resveratrol on inflammatory markers, oxidative stress parameters, mRNA expression levels of proteins and survival of lung cancer cells in Vitro. Materials and Methods: The A549 cell line was treated with benzo(a)pyrene, benzo(a)pyrene plus caffeic acid phenylester (CAPE), benzo(a)pyrene plus resveratrol (RES), and benzo(a)pyrene plus thymoquinone (TQ). Inflammatory markers, oxidative stress parameters, mRNA expression levels of apoptotic and anti-apoptotic proteins and cell viability were assessed and results were compared among study groups. Results: TQ treatment up-regulated Bax and down-regulated Bcl2 proteins and increased the Bax/Bcl2 ratio. CAPE and TQ also up-regulated Bax expression. RES and TQ down-regulated the expression of Bcl-2. All three agents decreased the expression of cyclin D and increased the expression of p21. However, the most significant up-regulation of p21 expression was observed in TQ treated cells. CAPE, RES and TQ up-regulated TRAIL receptor 1 and 2 expression. RES and TQ down-regulated the expression of NF-kappa B and IKK1. Viability of CAPE, RES and TQ treated cells was found to be significantly decreased when compared with the control group (p=0.004). Conclusions: Our results revealed up-regulation of the key upstream signaling factors, which ultimately cause increase in their regulatory p53 levels affecting the induction of G2/M cell cycle arrest and apoptosis. Overall these results provide mechanistic insights for understanding the molecular basis and utility of the anti-tumor activity of TQ, RES and CAPE.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.769-773
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• 2014

Fangchinoline (Fan) inhibits cell proliferation and induces apoptosis in several cancer cell lines. The effects of Fan on cell growth and proliferation in breast cancer cells remain to be elucidated. Here, we show that Fan inhibited cell proliferation in the MDA-MB-231 breast cancer cell line through suppression of the AKT/Gsk-3beta/cyclin D1 signaling pathway. Furthermore, Fan induced apoptosis by increasing the expression of Bax (relative to Bcl-2), active caspase 3 and cytochrome-c. Fan significantly inhibited cell proliferation of MDA-MB-231 cells in a concentration and time dependent manner as determined by MTT assay. Flow cytometry analysis demonstrated that Fan treatment of MDA-MB-231 cells resulted in cell cycle arrest at the G1 phase, which correlated with apparent downregulation of both mRNA and protein levels of both PCNA and cyclin D1. Further analysis demonstrated that Fan decreased the phosphorylation of AKT and GSK-3beta. In addition, Fan up-regulated active caspase3, cytochrome-c protein levels and the ratio of Bax/Bcl-2, accompanied by apoptosis. Taken together, these results suggest that Fan is a potential natural product for the treatment of breast cancer.