• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.795-806
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• 1996

A structure which transmits and receives 3 subscribers packet data through an optical splitter node in an optical subscriber network of PON wave suggested and realized. All the functions which are necessary to use PON structure such as 155.52Mb/s multiplexer/demultiplexer of down-stream signal, 25.92Mb/s multiplexer/demultiplexer of up-stream signal, frame synchronizer, and phase aligner for aligning phase of the clock and received data have been integrated within 2 ICs using CMOS technonology. TDMAtechnology was suggested for up-stream transmission. In the optical up-stream transmission of the urst signals transmissionquality degradataion by APC and AGC of optical tranceiver was observed. By compensating the degradation, more than 17dB of link budget which is enough to satisfy 11.2dBthat is required in SWAN of PON architecture has been obtained with optical transceiver whose power and sensitivity are -17dBm and -34dBm respectively.

• Journal of Magnetics
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• v.21 no.1
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• pp.12-19
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• 2016

The <100> oriented $Fe_{83}Ga_{17}$ alloys with various contents of NbC or B were prepared by directionally solidification method at the growth rate of $720mm{\cdot}h^{-1}$. With a small amount of precipitates, the columnar grains grew with cellular mode during directional solidification process, while like-dendrite mode of grains growth was observed in the alloys with higher contents of 0.5 at% due to the dragging effect of precipitates on the boundaries. The NbC precipitates disperse both inside grains and along the boundaries of $Fe_{83}Ga_{17}$ alloys with NbC addition, and the Fe2B secondary phase particles preferentially distribute along the grain boundaries in B-doped alloys. Precipitates could affect grain growth and improved the <100> orientation during directional solidification process. Small amount of precipitate element addition slightly increased the magnetostrictive strain, and a high value of 335 ppm under pre-stress of 15 MPa was achieved in the alloys with 0.1 at% NbC. Despite the fact that the effect on magnetic induction density of small amount of precipitates could be negligible, the coercivity markedly increased with addition of precipitate element for $Fe_{83}Ga_{17}$ alloy due to the retarded domain motion resulted by precipitates.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2403-2407
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• 2013

The hybrid density-functional (B3LYP/6-31G(d,p)) method was used to analyze the substitution effect on the $C_{20}H_{20}$ cage based on calculation of the frontier orbitals of fifteen $C_{20}H_{17}(OH)_3$ derivatives. All substitution products were geometrically optimized without constraints and confirmed by frequency analysis. The results suggest that the cis-1 cis-1 cis-2 regioisomer is the most stable isomer, which implies that hydrogen bonding exerts a stronger effect on the relative energies of the trihydroxide than long-range interactions. Thus, this supports the experimental result in which the bisvicinal tetrol was of particular preparative-synthetic interest. While the LUMO of each of the $C_{20}H_{17}(OH)_3$ regioisomers was equivalently delocalized over the void within the cage, the HOMO was limitedly delocalized on substituents and carbons in close proximity to the substituents. The characteristics of the HOMO of each of the regioisomers vary based on the substitution sites. This indicates that the 15 regioisomers of each $C_{20}H_{20}$ trisubstituted derivative might undergo an entirely different set of characteristic chemical reactions with electrophilic reagents. The results further suggest that the penta-substituted OH groups on the surface of the fullerene cage are more likely to be localized on a pentagon than to be homogeneously delocalized.

• Journal of Life Science
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• v.19 no.11
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• pp.1514-1521
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• 2009

To evaluate the feasibility of cathepsin-B levels in preoperatively screening patients with thyroid cancer, we assigned these patients to either the thyroid cancer group (n=32) or the nodular hyperplasia group (n=7). Five healthy volunteers served as controls (n=5). We quantified cathepsin-B expressions in cancerous lesions with follicular carcinoma and hyperplastic lesions with nodular hyperplasia, and compared the degrees to those of normal thyroid tissue, which was obtained from matched contralateral lobe. The activity of serum cathepsin B was significantly higher in patients with thyroid carcinoma ($284.87{\pm}79.32$, ${\times}10^{-2}\;mU$) and those with nodular hyperplasia ($255.45{\pm}95.68$, ${\times}10^{-2}\;mU$) than compared to normal control ($168.94{\pm}15.10$, ${\times}10^{-2}\;mU$) (p<0.05). Based on the results of immunoassay, the concentrations of cathepsin B in the thyroid cancer group ($15.50{\pm}7.86\;ng/ml$) and the nodular hyperplasia group ($17.64{\pm}7.49\;ng/ml$) were higher than those of the control group ($4.85{\pm}0.61\;ng/ml$). The degree of cathepsin-B mRNA expression was significantly higher in cancerous or hyperplastic lesions than normal thyroid tissues from matched contralateral lobe with follicular carcinoma or non-neoplastic thyroid disease. Our results indicate that the activity of serum cathepsin B is a useful indicator in screening patients with nodular hyperplasia or neoplastic thyroid disease and it may be involved in the abnormal proliferation of cells.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4659-4664
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• 2014

The noise produced in a factory is a cause of the noise complaint of the surrounding residential areas. In addition, it affects the work efficiency and health of workers. This paper presents the results of a basic study to reduce the noise generated from the blower, which is often used in the factory of a small and medium scale, using an active noise controller (ANC) in three-dimensional space. For this purpose, the simulator program, which can compare various parameters of the original noise and controlled noise, such as sound pressure levels, power spectra, and equivalent noise levels, was developed. The noise data was recorded at 17 points around a turbo fan blower currently being operated in a small-medium size factory. The simulation results showed that the power spectrum was reduced by a maximum of 40dB in the low frequency band and the average equivalent noise level attenuation was 12.6dB.

• Korean Journal of Crystallography
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• v.5 no.2
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• pp.78-84
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• 1994

The crystal structure of N-11-(benzotriazol-1-yl)butyl]-P-nitroaniline ( C16H17N502) has been determinedfromsingle crystal x-ray diffractionstudy:C16H17N502 monoclinic, P21/n, a=17542(2)A, b=10.755(3)A, c=8.891(1)A, β=104.58(1)˚, V=1623.4(5)A3, 7=293(2)K, Z=4, Cuka(A = 1.5418A) , The molecular structure was solved was by direct meshed refined by full-matrix least squares to a final R =0.0411 for 2248 unique observed [F≥4o(p) ] reflections and 255 Parameters. The crystal structure is stabilized by intermolecular N (11) -Hl 1 (Nl 1) ‥‥N (3) hydrogen bond with N(11) ‥‥ N(3) =3.136(2)A and N(11)-Hll(Nll)‥‥N(3) =164.1(15) ˚.

• Journal of Korean Neurosurgical Society
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• v.61 no.2
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• pp.180-185
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• 2018

Objective : Many lumbosacral fixation techniques have been described to offer a more screw-bone purchase. The forward anatomical fixation parallel to the endplate is still the most preferred method. Literature revealed little knowledge regarding the mechanical stability of lumbosacral trans-endplate fixation compared to the traditional trans-pedicular screw fixation method. The aim of this study is to assess the pull-out strength of lumbosacral screws penetrating the end plate and comparing it to the conventional trans-pedicular screw insertion method. Methods : Eight lumbar and eight sacral vertebrae, with average age 69.4 years, Left pedicles of the 5th lumbar vertebrae were used for trans-endplate screw fixation, group 1A, right pedicles were used for anatomical trans-pedicular screw fixation, group 1B. In the sacral vertebrae, the right side S1 pedicles were used for trans-endplate fixation, group 2A, left side pedicles were used for anatomical trans-pedicular screw fixation, group 2B. The biomechanical tests were performed using the axial compression testing machine. All tests were applied using 2 mm/min traction speed. Results : The average pull-out strength values of groups 1A and 1B were $403.78{\pm}11.71N$ and $306.26{\pm}17.55N$, respectively. A statistical significance was detected with p=0.012. The average pull-out strength values of groups 2A and 2B were $388.73{\pm}17.03N$ and $299.84{\pm}17.52N$, respectively. A statistical significance was detected with p=0.012. Conclusion : The trans-endplate lumbosacral fixation method is a trustable fixation method with a stronger screw-bone purchase and offer a good alternative for surgeons specially in patients with osteoporosis.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.117-123
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• 2006

In this paper, a CPW lowpass filter with the spurious-reduced characteristic is designed by using DGS(Defected Ground Structures). By cascading two lowpass filters with different harmonic characteristics the spurious is reduced below - 15 dB. Additionally by combining a dumbbell shaped DGS to the filter we achieved a satisfactory spurious level of less than -25 dB to above three times cutoff frequency without any repeated passband. The fabricated LPF shows a compact size of $17.2mm{\times}6.8mm$, a cutoff frequency of 6 GHz, and a sharp skirt response of 7-order with two notch frequencies. The measured frequency responses agree well with simulated ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.270-277
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• 2017

This study was carried out to investigate seasonal changes in body composition in Boleophthalmus pectinirostris in Korea. B. pectinirostris collected in Gangjin, Jeonnam, consisted of 58.7-75.8% moisture content, 16.1-17.6% protein, 0.8-3.4% crude lipids, and 1.3-3.6% crude ash. Livers consisted of 15-17% moisture content, 14.0-16.8% crude protein, 34.4-71.2% crude lipids, and 0.5-1.2% crude ash. Calcium, iron, potassium, etc., content in B. pectinirostris muscle averaged 267.5-599.8 mg/100 g, 1.98-28.3 mg, 160.7-327.9 mg, 20.6-60.2 mg, 0.4-2.2 mg, 0.23-0.46 mg, 66.5-192.9 mg, and 1.32-3.8 mg, respectively. (Please clarify: the list of measured values must correspond directly with what was measured, not just "etc.") The major amino acids in B. pectinirostris muscle, in proportional order, were glutamic acid, isoleucine, and leucine; whereas the major amino acids in the liver were glutamic acid, lysine, aspartic acid, and leucine. The major saturated fatty acids in the muscle were palmitic acid (15-19%) and stearic acid (8-11%). The major monoenes and polyenes were palmitoleic acid (C16:1) and oleic acid (C18:1), and EPA and DHA, respectively. The major saturated fatty acids and polyenes in the liver were the same as in muscle, but the monoenes were palmitoleic acid (C16:1) and cis-10-hepta-decenoic acid (C17:1). Seasonal changes in B. pectinirostris body composition may be attributable to differential accumulation of fat and nutrients in comparison to the spawning and hibernation period.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.5
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• pp.388-396
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• 2002

Quality characteristics of Yukwa, Korean traditional rice cookie, added with citrus peel (2, 4 and 6%) were investigated. Yukwa was prepared by adding the water homogenate of the peel and the quality characteristics were evaluated by the expansion rate, texture, color, sensory quality and content of total carotenoid, hesperidine and naringin. The expansion rate (1,517~855%) of Yukwa with higher concentrations of citrus peel powder was lower than that of control product (1,740%) and the brittleness followed the same trend. However, the values were in the range of those of the traditional Korean Yukwa. The color of the control Yukwa (L* value: 63.3~49.9, a* value: 10.6~17.8, b* value: 12.6~56.4) was white, but with citrus peel (2~6%) light yellow~yellow (L* value. 63.3~49.9. a* value: 10.6~17.8, b* values: 12.6~56.4). Carotenoid, hesperidin and naringin contents of Yukwa with the addition of peel powder were 0.18~0.51 mg%, 36.55~101.60 mg% and 24.65~70.81 mg%, respectively. The color and the overall acceptability of yukwa with 4% of citrus peel powder were the best. This combination had some orange flavor, but no differences in both sweet and sour taste.