• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.5
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• pp.355-365
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• 2017

In this paper, we propose the design of a dual-band GPS antenna using in-direct feeding pads. The antenna consists of an upper patch for the GPS L1 band, a lower patch for the GPS L2 band, and two pads on the middle layer for feeding the two radiating patches. A hybrid chip coupler with a phase difference of $90^{\circ}$ is employed at the two feeding ports for achieving a broad circular polarization (CP) bandwidth. The proposed antenna shows bore-sight gains of 3.0 dBic(L1) and 5.1 dBic(L2), and axial ratios of 3.3 dB(L1) and 0.3 dB(L2) by measurement. The active element patterns of the fabricated array with 7 elements show bore-sight gains of -0.4 dBic (L1) and -2.4 dBic(L2), respectively. It proves that the proposed antenna structure is suitable for use in GPS array applications.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.73-82
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• 2004

Chitosan is similar in structure to cellulose and are the second most abundant polysaccharides in nature, comprising the horny substance in the exoskeletons of crabs, shrimp and insects as well as fungi. This study was conducted to access the effect of immunomodulation responses of chitosan(N-acetyl-${\beta}$-D-glucosamine) chicken infected with in Fowl typhoid(Salmonella gallinarum). One-day-old broiler chicks were divided into eight groups: The 1st group was inoculated intra-peritoneally with chitosan and challenged intra-peritoneally with S. gallinarum. The 2nd group was inoculated intra-peritoneally with chitosan. The 3rd group was feeding with chitosan and intra-peritoneally inoculated with cyclophosphamide and challenged intra-peritoneally S. gallinarum. The 4th group was feeding with chitosan and intra-peritoneally with cyclophosphamide. The 5th group was feeding with chitosan and challenged intra-peritoneally with S. gallinarum. The 6th group was feeding with chitosan. The 7th group was challenged intra-peritoneally with S. gallinarum. The 8th group was nontreated-uninfected control group. The results shows that $CD4^+$, $CD8^+$ and B lymphocyte in lymphoid organs of chickens treated with chitosan increased in especially $CD4^+$, $CD8^+$ lymphocytes (p<0.05). The group of feeding chitosan showed the significantly increased $CD4^+$, $CD8^+$ and B lymphocyte than inoculated intra-peritoneally with chitosan. As the result suggests that the feeding of chitosan induced immunostimulatant effect than the inoculation intra-peritoeally of chitosan.

• 한국해양학회지
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• v.21 no.4
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• pp.236-244
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• 1986

This study was carried out for appreciable information on the proper habitats and feeding modes of some dominant polychaetes in the continental shelf of the East Sea during April, 1985. Among 95 polychaete species, we select ed 9 dominant species in terms of their occurring frequency, abundance and population density. These are Terebellides stroemi, Chaetozone setosa, Magelona japonica, Ampharete arctica, Aglaophamus sinensis, Nothria holobranchiata, Lumbrineris japonica, Myriochele gracilis, Notoproctus pacificus. Major food item s of these species are centric diatoms and detritus. The feeding modes of the the m are mainly surtace or subsurface deposit feeding, though two specters, M.holobranchiata and L. japonica, could be assumed to be potential carnivores. To a certain degree, most deposit feeders in the coarse sediments showed selectivity in feeding and tube building. The feeding mode, gut content and the tube structure, and the distribution pattern of dominant polychaetes correspond well with the habitat tharacters, e.g.the bottom topography, the source of food and the sediment composition.

• Journal of electromagnetic engineering and science
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• v.15 no.2
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• pp.115-119
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• 2015

This paper proposes a reconfigurable square-patch antenna with polarization diversity. The proposed antenna consists of a square radiating patch and a Y-shaped feed structure with two PIN diodes. The shape of the feed structure can be changed by adjusting the bias states of the two PIN diodes, which helps switch between two orthogonal linear polarizations. The polarization diversity characteristic is validated by the simulated current distribution and the measured radiation pattern.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.461-466
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• 2019

In this paper, we have studied the improvement of gain and bandwidth characteristics by using double feeding and L-shaped inset feed line matching circuit in microstrip stacked patch antenna which is widely used to broaden the gain of general microstrip antenna. The proposed structure is composed of two feeding edges of the main patch antenna, each of them are connected to a feeding line having an L shaped inset feeder. And the parasitic patch is placed at a proper distance above the main patch. The size of the main patch is designed so that the resonance frequency is close to the center frequency of the target frequency band. The experimental results show that the bandwidth was increased more than 180MHz in the 2.3-2.7 GHz band, which is more interesting than the single feed, and the gain improvement of 2.5dBi was obtained at 2.7GHz.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.325-337
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• 2014

To assess the functional structure of prepro-melanin-concentrating hormone (pMCH), we isolated and cloned pMCH (of-pMCH) mRNA from the brain of the olive flounder, Paralichthys olivaceus, and compared its amino acid sequence with those from other animals. In addition, to examine whether activation of the brain of-pMCH gene is influenced by background color, density, and feeding, we compared pMCH mRNA activities against different background colors (bright and dark) and at different densities (100% PCA and 200% PCA). To examine whether the pMCH gene is related with malpigmentation of blind-side skin and appetite, we compared pMCH gene expression between ordinary and hypermelanic flounders, and between feeding and fasting flounders. The of-pMCH cDNA was 405 bp in the open reading frame [ORF] and encoded a protein of 135 amino acids; MCH was 51 bp in length and encoded a protein of 17 amino acids. An obvious single band of the expected size was obtained from the brain and pituitary by RT-PCR. In addition, of-pMCH gene activity was significantly higher in the bright background only at low density (< 100% PCA) making the ocular skin of fish whitening, and in ordinary fish. However, the gene activity was significantly decreased in dark background, at high density (>200% PCA), and in hypermelano fish. These results suggest that skin whitening camouflage of the flounder is induced by high MCH gene activity, and the density disturbs the function of background color in the physiological color change. Moreover, our data suggest that a low level of MCH gene activity may be related to malpigmentation of the blind-side skin. In feeding, although pMCH gene activity was significantly increased by feeding in the white background, the pMCH gene activity in the dark background was not influenced by feeding, indicating that the MCH gene activity increased by feeding can be offset by dark background color, or is unaffected by appetite. In conclusion, this study showed that MCH gene expression is related to ocular-skin whitening camouflage and blind-skin hypermelanosis, and is influenced by background color and density.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.5
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• pp.659-665
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• 2016

The effects of three different feeding systems on beef cattle production performance, rumen fermentation, and rumen digesta particle structure were investigated by using 18 Limousin (steers) with a similar body weight ($575{\pm}10kg$) in a 80-d experiment. The animals were equally and randomly divided into three treatment groups, namely, total mixed ration group (cattle fed TMR), SI1 group (cattle fed concentrate firstly then roughage), and SI2 group (cattle fed roughage firstly then concentrate). The results showed that the average daily gain was significantly higher in cattle receiving TMR than in those receiving SI1 and SI2 (p<0.05). Consumption per kg weight gain of concentrate, silage, and combined net energy (NEmf) were significantly decreased when cattle received TMR, unlike when they received SI1 and SI2 (p<0.05), indicating that the feed efficiency of TMR was the highest. Blood urea nitrogen (BUN) was significantly decreased when cattle received TMR compared with that in cattle receiving SI1 (p<0.05), whereas there was no difference compared with that in cattle receiving SI2. Ammonia nitrogen concentration was significantly lower in cattle receiving TMR than in those receiving SI1 and SI2 (p<0.05). The rumen area of cattle that received TMR was significantly larger than that of cattle receiving SI1 (p<0.05), but there was no difference compared with that of cattle receiving SI2. Although there was no significant difference among the three feeding systems in rumen digesta particle distribution, the TMR group trended to have fewer large- and medium-sized particles and more small-sized particles than those in the SI1 and SI2 groups. In conclusion, cattle with dietary TMR showed increased weight gain and ruminal development and decreased BUN. This indicated that TMR feeding was more conducive toward improving the production performance and rumen fermentation of beef cattle.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.2
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• pp.251-258
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• 2023

In this paper, we propose DLP(Dual Linear Polarization) stack antenna for private network. The proposed antenna has general stack structure and design airgap between two substrate to obtain the maximum gain. Also, to improve cross polarization isolation, two feeding port is designed to separate for each substrate. The size of each patch antenna is 17.80 mm(W1)×16.70 mm(L1) for lower patch and 18.56 mm(W2)×18.73 mm(L2) for upper patch, which is designed on the FR-4 substrate which thickness (h) is 1.6 mm, and the dielectric constant is 4.3, and which is 40.0 mm(W)×40.0 mm(L) for total size of substrate. From the fabrication and measurement results, bandwidths of 100 MHz (4.74 to 4.84 GHz) for feeding port 1, and 150 MHz (4.67 to 4.82 GHz) for feeding port 2 are obtained on the basis of -10 dB return loss and transmission coefficient S21 is got under the -20 dB. Also, cross polarization isolation between each feeding port obtained

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.233-239
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• 2016

The purpose of this study is to investigate the response of the soil mesofauna and ground-dwelling arthropods to vegetation structure and composition in a mountain pasture. The pasture mainly comprised five types of plant communities; Agrostis alba - Phleum pratense community, Poa pratensis community, Festuca ovina community, Rumex acetosella community, and the shrub assemblage comprised Spiraea miyabei-Spiraea salicifolia community. Soil chemical properties including the pH, EC and nutrient levels were influenced by plant communities. Plant-specific responses were observed for bacteria-feeding and plant-feeding soil nematodes. Collembola and Oribatida having the same feeding habit were influenced differently by plants. nMDS showed that the community of ground-dwelling arthropods were separated by vegetation types. Species numbers of arthropods were different among different plant communities. Our results indicate that vegetation structure and composition can influence both abundance of diversity of terrestrial fauna.

• Journal of IKEEE
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• v.27 no.4
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• pp.405-410
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• 2023

This paper presents a novel method of implementing a dual-band antenna using a square patch with an inset feed structure. The proposed method is to simply design a dual-band antenna using an asymmetric inset structure with different lengths of slots dug into the patch for inset feeding. To verify the proposed method, a dual-band inset patch antenna supporting 1.57 GHz GPS and 2.4 GHz WiFi bands was designed and manufactured on a 1 mm thick FR4 substrate. From measurement, it was confirmed that the frequency bands of the antenna that satisfy a return loss of -10dB or less are 1.55~1.57GHz and 2.41~2.45GHz, which has dual-band characteristics. Using the proposed method, it is possible to simply implement a dual-band antenna using inset feeding, and it is expected to be utilized in a variety of application fields.