• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.2
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• pp.31-40
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• 1999

Characteristics of monopole antenna and planar conductor structure mounted on handheld telephone are anlayzed by using FDTD method. Feeding of monopole antenna is implemented with lumped elements and plastic case is coated on the surface of conductor box. Otherwise, resonant frequency of handheld telephone mounting monopole antenna with no plastic case is 877MHz, when plastic case (${\varepsilon}_r=2$) is coated, the resonant frequency is down to 82MHz and the bandwidth is broadened about 1.5 times. Planar structure of handheld telephone mounted on the body makes to change far-field gain radiation patterns. In this case, radiation patterns are somewhat asymmetrical. Handheld telephone using PIFA(Planar Inverted F Antenna), instead of monopole antenna, is resonated at frequency 1.52GHz that is available onPCS. In the radiation pattern of this structure, azimuth that electric field intensity is presented below 20dB is 14$^{\circ}$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.3
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• pp.261-268
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• 2016

In this paper, dual-polarized monopulse cassegrain antenna for W-band millimeter-wave seeker was proposed and the performances were verified by the measured results of the fabricated antenna. Dual-polarized monopulse Cassegrain antenna consists of main/subreflector, dual-polarized feed horn and monopulse comparator. The proposed feed horn has $2{\times}2$ array square waveguide feeding structure to make monopulse signals and it was designed using 90 degree rotational symmetric structure to receive dual-polarized signals. At the sum and difference channel, the measured vertical and horizontal polarization radiation pattern were similar. Measurement gains are 35.1 dBi for v-pol. and 35.6 dBi for h-pol. at the center frequency with 0.5dBi difference between each polarization and the side lobe level is below -21.6 dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.612-620
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• 2008

In this parer, parabolic edge planar monopole antenna for UWB communication is presented. The antenna have broadband property structurally through planar monopole and ground which have parabolic edge. It is designed close to self-complementary structure as changing curvature of edge of monopole and ground. Monopole and ground of proposed antenna exist on coplanar plane, and excite as coaxial feeding. It used FR4 dielectric substrate of ${\varepsilon}_r=4.4$, and the size is $26{\times}31{\times}1.6mm$. Return loss is more than 10 dB in $3.1{\sim}10.6GHz$. Radiation pattern is about the same that of dipole antenna at all frequency. At measured result, max gain is $1.37{\sim}6.02dBi$ at E-plane.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.161-168
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• 1997

To clarify the effect of anti-juvenile hormone analogue (AJH) on the larval ecdysis by feeding at early stage of the 4th instar, the total amount of protein and activity of chitinolytic enzymes in the integument of Bombyx mori were analyzed, PAGE pattern of the protein was observed and the morphological changes of integument during molting period were also observed and the morphological changes of integument during molting period were also observed by means of TEM. The total amount of protein was greatly increased in premolting, then reached maximum level just before ecdysis, and rapidly decreased after the larval ecdysis in the control, while in the AJH treatment, increased 12 hr later than the control and its maximum was only 82.6% of the control. Two specific proteins, which were presumed as the protein originated from endocuticle, also appeared 12 hr later than the control and were maintained to 132 hr after AJH treatment from the aspects of the Native- and SDS-PAGE patterns, although those of the control disappeared instantly after ecdysis. Chitinase and $\beta$-N-acetylglucosaminidase activities were also suppressed and delayed by AJH treatment. Furthermore, it was observed that the apolysis took place 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control by AJH treatment but no further processing takes place just after apolysis.

• Journal of Nutrition and Health
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• v.16 no.4
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• pp.287-295
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• 1983

Sprague Dawley pregnant rats were fed the hydrogenated coconut oil (P/S 0.02), corn-oil plus beef tallow (P/S 1.0), and corn-oil(P/S 4.0)diet during the 14 days of gestation and through lactation. At weaning, offsprings from each group were divided into two and corn- oil diet was switched to coconut and vice versa, while the other corresponding groups continud the same diet. Body, brain, and liver weights were measured on pups and the brains were analyzed for DNA and vitamin E. Serum and liver vitamin E levels were alse measured. Body weight of coconut group was significantly low throughout the 7 week period, but brain weight was significantly depressed before weaning. Liver weight showed similar pattern with the body weight. Serum vitamin levels increased before weaning, while tissue vitamin E increased after weaning. Serum vitamin E levels of switched groups were similar to that of P/S 1.0 group. Brain vitamin E levels per DNA of switched groups were also similar to that of P/S 1.0 group. And the effect of different dietary essential fatty acid levels on vitamin E in the brain during lactation found to be insignificant.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.43-49
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• 2002

We have cloned cDNAs encoding toxin from the spider, Araneus ventricosus, and constructed a recombinant baculovirus expressing the insecticidal toxin. The cDNAs encoding toxin were cloned from the cDNA library of A. ventricosus. Sequence analysis of the cDNAs encoding the toxin of A. ventricosus revealed that the 240 bp cDNA for AvTox-1 and 192 bp cDNA for AvTox-2 have an open reading frame of 80 and 64 amino acid residues, respectively. The deduced protein sequence of the toxin genes of AvTox-1 and AvTox-2 was aligned to that of the snack Anemonia sulcata and scorpion Centruroides limpidus limpidus, respectively. Northern blot analysis indicated that AvTox-2 toxin gene showed a fat body-spe-cific expression pattern at the transcriptional level. Furthermore, we have explored the possibility of improving baculovirus by incorporating the A. vontricosus toxin gene into Bombyx mori nuclear polyhedrosis virus genome under the control of polyhedrin promoter, The AvTox-2 toxin gene was expressed as approximately 5.8 kDa band in the recombinant baculovirus-injected silkworm larvae. Bioassays with the recombinant virus expressing AvTox-2 on 5th instar silkworm larvae demonstrated a decrease in the time to kill $(LT_{50} days)$ compared to wild-type BmNPV-Kl $(LT_{50} 6.72 days)$ in the injection of 10 viruses. These results indicate that A. ventricosus toxin is a novel member of the spider toxin family, suggesting that the toxin gene can be used in recombinant baculoviruses to reduce insect feeding damage and increase the speed of insect kill.

• Journal of Community Nutrition
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• v.7 no.1
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• pp.3-7
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• 2005

This study was conducted to evaluate nutritional status of school children by biochemical assessment method. Subjects were 308 school children from 4th to 6th grade living in Bucheon city. Their blood glucose, total protein, albumin, total cholesterol, and triglyceride (TG) concentrations were determined. Mean blood glucose concentration was 77.56 mg/dl and $81.2\%$ of children had normal blood glucose concentration. The average proportion of hypoglycemia was $18.8\%$ among the three grades and prevalence of hypoglycemia in 4th grade school children was highest ($21.8\%$). Mean serum total protein and albumin levels were 7.14g/dl and 4.35g/dl, respectively, and all the subjects except only one were in normal range of total protein and albumin. Mean serum TG and total cholesterol concentrations were 145.82mg/dl and 94.50mg/dl. Serum TG and total cholesterol levels showed same pattern that the concentrations decreased in proportion to grade. Especially, there was significant difference between grades in serum total cholesterol. Furthermore, $11.7\%$ of 4th, $6.8\%$ of 5th, and $2.8\%$ of 6th grade school children have borderline hypertriglycemia or hypertriglycemia, risk factors of obesity or cardiovascular disease later in life. Taken together, there was conflict phenomenon that undernutrition of hypertriglycemia and overnutrition of hypertriglycemia existed together. Therefore, it is needed to develop discriminating and personalized nutritional feeding, counseling, and education program to cover the children of under- or over- nutritional status.

• Journal of Nutrition and Health
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• v.37 no.1
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• pp.52-60
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• 2004

This study was conducted to investigate the bone mineral density (BMD) and the anthropometric measurements, socioeconomic factors, family history of osteoporosis and other environmental factors affecting BMD in children. One hundred sixty children (80 males, 80 females) in second grade of elementary school in Seoul were recruited; the mean age was 7.7 $\pm$ 0.47 years. Bone mineral density was measured in the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and Ward's triangle (WT) by Dual Energy X-ray Absorptiometry (DEXA). Socioeconomic factors, family history of osteoporosis, and other environmental factors were assessed by questionnaire. Bone mineral densities of LS, FN, FT, and WT were 0.677, 0.637, 0.618, and 0.658 g/$\textrm{cm}^2$. BMD of boys was higher than that of girls (LS: 0.685 vs. 0.669, FN: 0.660 vs. 0.614, FT: 0.632 vs. 0.604, WT: 0.678 vs. 0.639 g/$\textrm{cm}^2$). Anthrometric measurements (height, weight relative body weight, circumference of waist and hip) were positively correlated with BMD. With increasing family income, BMD of LS was significantly lowered, and negative correlation was observed between mother's age at birth of subject and the BMD of FN. And the BMD of children with a family history of osteoporosis was significantly lower. However BMDs were not different by educational level of parents, family pattern, delivery term, birth weight, and type of feeding. Further studies are needed to clarify the factors affecting BMD of children and earlier age, included infants and even prenatal life. If any association is revealed and persist until the attainment of peak bone mass, osteoporosis prevention programs are needed to be start very early in the life cycle.

• Journal of Satellite, Information and Communications
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• v.12 no.1
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• pp.94-100
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• 2017

In this paper, we suggest a design method of a metamaterial-based low-profile antenna working at 425 MHz for LEO/Cube satellites. Satellites play an important role in linking th remote nodes in a wireless communication network and covering wide areas of the globe. Especially, an increasing number of universities or individuals aspire having their own satellites and build low-budget structures such as cube satellites in LEO and the ways to reduce the sizes of their satellites. Since the antenna occupies a major portion of the satellite surface, the antenna should be miniaturized for lighter weight. The proposed metamaterial low-profile antenna, unlike the conventional patch antenna, produces such a zeroth-order resonance to create an omnidirectional radiation pattern. Also, it is connected to a UHF waveguide bandpass filter as the feeding system to examine the possible change in the situation that the antenna is combined with the system. The performances of the monopole and proposed metamaterial antennas are compared to one another.

• Journal of Advanced Navigation Technology
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• v.7 no.2
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• pp.101-107
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• 2003

In this study, we provide a single element log-periodic antenna that the feeding networks and array structures are aperture coupled and series dipole array type. We made the antenna for direct receiving the Moogoongwha satellite broadcasting signal. The transmission power was able to feed the patch dipole in series due to lay perpendicularly 8 series patch dipole on tapered slot. The patch dipole radiation pattern which fed in series power, make the main beam direction up $37^{\circ}{\sim}42^{\circ}$ within the BS/CS bandwidth. The main beam gain was measured 9.31~11.03 dBi. Using 32 elements to array the elements properly, we acquire $4{\times}8$ array structure on limited PCB board. As a result, it has been found that the new planar DBS antenna structure have high gain over 10dBi and acceptable elevation angle over 42 degree, and we can apply this result to commercial DBS reception antenna manufacturing.