• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2359-2366
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• 2014

In this paper, the characteristics of a inset fed rectangular microstrip patch antenna for S-band applications is studied. The variations of return loss along inset length and inset width are investigated on the inset fed rectangular microstrip patch antenna. From the investigated results, the optimized inset fed antenna is designed. At the resonant frequency 2.3 GHz, the optimized dimension of the patch is $45.0mm{\times}40.9mm$. The inset length and width are 14 mm and 1 mm, respectively. The designed antenna is fabricated on the substrate which has a dielectric constant and thickness with 2.5 and 0.787 mm. Simulation results are obtained by a 3D EM(Electromagnetic) solver. The resonant frequency and return loss are measured 2.3025 GHz and -21.11 dB, respectively. The measured and simulated results of the fabricated antenna are in good agreement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.244-248
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• 2001

According to the progress of the electronic industry and radio communication technologies, mankind might enjoy its abundant life. On the other hand, many social problems such as EMI, and unnecessary electromagnetic wave occur due to the increased use of electromagnetic wave. Therefore, the organizations such as CISPR, FCC, ANSI, etc. have provided the standard of electromagnetic wave environment for the countermeasure of the EMC. It had been required that the absorbing ability of an electromagnetic wave absorber is more than 20dB, the bandwidth of which is required through 30 MHz to 1,000 MHz for satisfying the international standard about an anechoic chamber for EMI/EMS measurement. From November of 1998, however, the CISPR11 has accepted the extended frequency band from 1 GHz to 18 GHz additionally in the bandwidth of EMI measurement[1]. In this paper, we proposed a new type absorber satisfying the above requirements and carried out broadband design using the equivalent material constants method. Futhermore, the experiments were carried out over the frequency band from 30 MHz to 2 GHz, and hence, the validity of the proposed design theory was confirmed.

• ALGAE
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• v.29 no.2
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• pp.137-152
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• 2014

Mixotrophic protists play diverse roles in marine food webs as predators and prey. Thus, exploring mixotrophy in phototrophic protists has emerged as a critical step in understanding marine food webs and cycling of materials in marine ecosystem. To investigate the feeding of newly described mixotrophic dinoflagellate Ansanella granifera, we explored the feeding mechanism and the different types of species that A. granifera was able to feed on. In addition, we measured the growth and ingestion rates of A. granifera feeding on the prasinophyte Pyramimonas sp., the only algal prey, as a function of prey concentration. A. granifera was able to feed on heterotrophic bacteria and the cyanobacterium Synechococcus sp. However, among the 12 species of algal prey offered, A. granifera ingested only Pyramimonas sp. A. granifera ingested the algal prey cell by engulfment. With increasing mean prey concentration, the growth rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but became saturated at a concentration of $434ngCmL^{-1}$ (10,845 cells $mL^{-1}$). The maximum specific growth rate (i.e., mixotrophic growth) of A. granifera feeding on Pyramimonas sp. was $1.426d^{-1}$, at $20^{\circ}C$ under a 14 : 10 h light-dark cycle of $20{\mu}Em^{-2}s^{-1}$, while the growth rate (i.e., phototrophic growth) under similar light conditions without added prey was $0.391d^{-1}$. With increasing mean prey concentration, the ingestion rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but slightly at the concentrations ${\geq}306ngCmL^{-1}$ (7,649 cells $mL^{-1}$). The maximum ingestion rate of A. granifera feeding on Pyramimonas sp. was 0.97 ng C $predator^{-1}d^{-1}$ (24.3 cells $grazer^{-1}d^{-1}$). The calculated grazing coefficients for A. granifera feeding on co-occurring Pyramimonas sp. were up to $2.78d^{-1}$. The results of the present study suggest that A. granifera can sometimes have a considerable grazing impact on the population of Pyramimonas spp.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4549-4553
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• 2012

This study was designed to investigate the frequency of CYP2D6 polymorphisms and evaluate the association between genetic polymorphisms of CYP2D6 and tamoxifen therapeutic outcome in Thai breast cancer patients. We recruited 48 breast cancer patients who received adjuvant tamoxifen for evaluating CYP2D6 genetic polymorphisms using microarray-based technology. Associations between genotypes-phenotypes and disease free survival were analyzed. Median follow up time was 5.6 years. The mean age of the subjects was 50 years. The 3 common allelic frequencies were 43.8% ($^*10$), 36.5 ($^*1$) and 10.4% ($^*2$) which are related to extensive metabolizer (EM) and intermediate metabolizer (IM) with 70.8% and 29.2 %, respectively. No association between CYP2D6 genotypes and DFS was demonstrated. Nevertheless, exploratory analysis showed statistically significant shorter DFS in the IM group of post-menopause patients (HR, 6.85; 95%CI, 1.48-31.69; P=0.005). Furthermore, we observed statistically significant shorter DFS of homozygous $CYP2D6^*10$ when compared with heterozygous CYP2D6*10 and other genotypes (P=0.005). $CYP2D6^*10$ was the most common genotype in our subjects. Post-menopause patients with homozygous $CYP2D6^*10$ and IM have shorter DFS. To confirm this relationship, larger samples and comprehensively designed trials in Thailand are required.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.10
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• pp.1021-1030
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• 2009

We propose optimization method of two-inductor loaded small loop antennas using simple genetic algorithm. To optimize the loop antennas for the RFID and the mobile phone band, we changed positions and values of the two inductors in the loop antenna. Visual basic was used to make genetic algorithm and to calculate fitness values by controlling the commercial EM software. The bandwidth of the optimized RFID loop antenna is 10 MHz at the center frequency of 922 MHz and that of the mobile phone antenna are 84 MHz and 266 MHz at the center frequency of 948 MHz(GSM band) and 1.81 GHz(DCS band), respectively.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.1
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• pp.57-63
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• 2014

In this paper, we have proposed a wide band antenna for manpack SDR(Software Defined Radio). The proposed antenna consists of feeding post, flexible gooseneck and two radiating elements composed of a upper and lower radiators. The upper radiator has a longer electrical length than the lower radiator in order to operate in the lower frequency. Also, the resonant frequency and impedance characteristics of the antenna can be adjusted independently for two radiators. Therefore, the proposed antenna can be achieved wide impedance bandwidth by the combination of two independent resonance modes. To analyze the characteristics of the antenna in the design process is employed the equivalent circuit theory and EM(Electro-Magnetic) simulation. The measurement results show that the proposed antenna have the sufficient wide bandwidth, above -3.4dBi of the gain and fairly good radiation pattern over the wide bandwidth.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.104-109
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• 2012

In this paper, we propose a way to improve the quality of L-band wireless communication from unfriendly influential factors lying in the neighboring RF bands. The UHF-band system has resonator components and they generate harmonics as the spurious in the L-band. Therefore, a metamaterial CRLH bandpass filter is designed for the purpose of system miniaturization and smaller insertion loss, and its spurious phenomenon is observed in the frequency domain. And its harmonics in the L-band are suppressed by a compact bandstop filter whose equivalent circuit is newly developed. The design methodology is validated by the equivalent circuit to be compared with commercial full-wave EM software simulations, where the spurious is dropped by 20dB. Also, the advantage of the proposed design is presented by the comparison where our filter is much smaller than the conventional parallel edge coupled filter by over 50%, with excellent harmonic suppression.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.3
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• pp.201-207
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• 2002

Objective: To observe the capability of fertilization and embryo development including blastocyst formation of the oocytes in simple media after thawing of the cryopreserved cumulus-free mouse oocytes by vitrification method. Methods: Oocytes were collected from 5 to 6 weeks old ICR female mice, and were denuded from the cumulus cells by 0.1% hyaluronidase. Recovered mature oocytes in study group were cryopreserved by vitrification method using EM grid for $5{\sim}7$ days. In brief, oocytes were exposed in dPBS containing 1.5 M EG and 5.5 M EG+1 M sucrose for 2.5 minutes and 20 seconds each, and then executed vitrification by plunging in LN2 after loading on EM grid. Thawing treated by exposure of 1, 0.5, 0.25 and 0.125 M sucrose solution for 2.5 minutes each in order and used for experiments. Spermatozoa aspirated form the epididymis of 12 weeks old ICR male mice were used for insemination after capacitation. T6 media containing 0.4% BSA were used for fertilization and development. Results: Survival and fertilization rates after thawing were 76.9% and 79.6% respectively. Fertilization rate was lower (p<0.005) than that of control group (92.9%). There was no difference in embryo developmental rates from 2-cell to morula, however, the blastocyst formation rate and mean cell numbers of blastocysts in study group (63.3%, $58.9{\pm}9.2$) were lower compared with those of control group (76.1%, $63.5{\pm}8.9$). Conclusion: Vitrification is an effective method for mouse mature oocyte cryopreservation with high survival and fertilization rate after thawing. And in simple media, fertilization rates and embryo development of frozen-thawed mouse oocytes are satisfactory.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.3-7
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• 2005

The insulin-like growth factors (IGFs), their receptors, and their binding proteins play key roles in regulating cell proliferation and apoptosis. Insulin-like growth factor binding protein-3 (IGFBP3, OMIM #146732) is one of the proteins that bind to the IGFs. IGFBP3 is a modulator of IGF bioactivity, and direct growth inhibitor in the extravascular tissue compartment. We identified twenty-two novel single nucleotide polymorphisms (SNPs) in IGFBP3 gene in Korean cattle (Hanwoo, Bos taurus coreanae) by direct sequencing of full gene including -1,500 bp promoter region. Among the identified SNPs, five common SNPs were screened in 650 Korean cattle; one SNP in promoter (IGFBP3 G-854C), one in 5'UTR region (IGFBP3 G-100A), two in intron 1 (IGFBP3 G+421T, IGFBP3 T+1636A), and one in intron 2 (IGFBP3 C+3863A). The frequencies of each SNP were 0.357 (IGFBP3 G-854C), 0.472 (IGFBP3 G-100A), 0.418 (IGFBP3 G+421T), 0.363 (IGFBP3 T+1636A) and 0.226 (IGFBP3 C+3863A), respectively. Haplotypes and their frequencies were estimated by EM algorithm. Six haplotypes were constructed with five SNPs and linkage disequilibrium coefficients (|D'|) between SNP pairs were also calculated. The information on SNPs and haplotypes in IGFBP3 gene could be useful for genetic studies of this gene.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.2
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• pp.184-192
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• 2001

In this paper, we analyze the result of the conduced emission and susceptibility tests performed on the KOMPSAT-I ETB Platform. The ETB platform consists of the EM (Engineering Model) boxes developed to perform the electrical functional test. During the conducted emission test, we measured the instant waveform in time domain when each switch was turn on, and spectrum of the noise in the frequency range of 10 Hz up to100 MHz fur the steady state of the ETB. During the conducted susceptibility test, no malfunction and no serious damage of the electronic box were observed when a simulated noise waveform was applied to the DC power bus. The simulated waveform was obtained by adding the 6 dB-system margin to the worst case waveform measured from the conducted emission. This test was performed as co-development of the KOMPSAT-I with TRW in USA.