• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.11B
• /
• pp.1588-1595
• /
• 2010

DVB-C2 is the next generation digital broadcasting standard which will replace the analog cable broadcasting. LDPC and BCH significantly increase performance of forward error correction and allows for the application of higher constellation. Additionally, DVB-C2 is based on OFDM instead of single-carrier modulation, which gives additional flexibility and robustness in typical cable channels. This paper will give an introduction to the DVB-C2 system and spectral efficiency of DVB-C2 compare with DVB-C. Finally, The the simulation which is using BICM and OFDM structure show the performance of the DVB-C2.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.5
• /
• pp.529-535
• /
• 2014

In this paper, we propose a hybrid approach towards multiple kernels interval type-2 possibilistic fuzzy C-means(PFCM) based on interval type-2 possibilistic fuzzy c-means(IT2PFCM) and possibilistic fuzzy c-means using multiple kernels( PFCM-MK). In case of noisy data or overlapping cluster prototypes, fuzzy C-means gives poor performance in comparison to possibilistic fuzzy C-means(PFCM). Moreover, to address the uncertainty associated with fuzzifier parameter m, interval type-2 possibilistic fuzzy C-means(PFCM) is used. Most of the practical data available are complex and non-linearly separable. In such cases using Gaussian kernels proves helpful. Therefore, in order to overcome all these issues, we have integrated multiple kernels possibilistic fuzzy C-means(PFCM) into interval type-2 possibilistic fuzzy C-means(IT2PFCM) and propose the idea of multiple kernels based interval type-2 possibilistic fuzzy C-means(IT2PFCM-MK).

• Kyungpook Mathematical Journal
• /
• v.56 no.3
• /
• pp.781-791
• /
• 2016

Let $d_*(1,w)^2 ={\mathbb{R}}^2$ with the octagonal norm of weight w. It is the two dimensional real predual of Lorentz sequence space. In this paper we classify the smooth points of the unit ball of the space of symmetric bilinear forms on $d_*(1,w)^2$. We also show that the unit sphere of the space of symmetric bilinear forms on $d_*(1,w)^2$ is the disjoint union of the sets of smooth points, extreme points and the set A as follows: $$S_{{\mathcal{L}}_s(^2d_*(1,w)^2)}=smB_{{\mathcal{L}}_s(^2d_*(1,w)^2)}{\bigcup}extB_{{\mathcal{L}}_s(^2d_*(1,w)^2)}{\bigcup}A$$, where the set A consists of $ax_1x_2+by_1y_2+c(x_1y_2+x_2y_1)$ with (a = b = 0, $c={\pm}{\frac{1}{1+w^2}}$), ($a{\neq}b$, $ab{\geq}0$, c = 0), (a = b, 0 < ac, 0 < ${\mid}c{\mid}$ < ${\mid}a{\mid}$), ($a{\neq}{\mid}c{\mid}$, a = -b, 0 < ac, 0 < ${\mid}c{\mid}$), ($a={\frac{1-w}{1+w}}$, b = 0, $c={\frac{1}{1+w}}$), ($a={\frac{1+w+w(w^2-3)c}{1+w^2}}$, $b={\frac{w-1+(1-3w^2)c}{w(1+w^2)}}$, ${\frac{1}{2+2w}}$ < c < ${\frac{1}{(1+w)^2(1-w)}}$, $c{\neq}{\frac{1}{1+2w-w^2}}$), ($a={\frac{1+w(1+w)c}{1+w}}$, $b={\frac{-1+(1+w)c}{w(1+w)}}$, 0 < c < $\frac{1}{2+2w}$) or ($a={\frac{1=w(1+w)c}{1+w}}$, $b={\frac{1-(1+w)c}{1+w}}$, $\frac{1}{1+w}$ < c < $\frac{1}{(1+w)^2(1-w)}$).

• The Journal of Korean Society for Radiation Therapy
• /
• v.21 no.1
• /
• pp.9-15
• /
• 2009

Purpose: We evaluated the device that was created for maintaining the patient's setup and protecting the testicles from scattered radiation during treatment of carcinoma of the penis. Materials and Methods: The phantom testicles were made of vaseline cotton gauze and the device consisted of 5 mm of acryl box and 4 mm of lead shielding. $3{\times}3\;cm^2$, $4{\times}4\;cm^2$, $5{\times}5\;cm^2$, $6{\times}6\;cm^2$, $7{\times}7\;cm^2$ field sizes were used for this study and measurement was made at 4, 5, 6, 7, 8, 10 cm from the lower edge of the field for 10 times with lead shielding and without the shielding respectively. 200 cGy was delivered using 6 MV photons. Results: The scatted radiation without lead shielding at 4, 5, 6, 7, 8, 10 cm from the lower edge of the field were 14.8-4.7 cGy with $3{\times}3\;cm^2$, 15.7-5.2 cGy with $4{\times}4\;cm^2$, 17.6-5.5 cGy with $5{\times}5\;cm^2$, 19.9-6.6 cGy with $6{\times}6\;cm^2$, 22.2-7.6 cGy with $7{\times}7\;cm^2$ and the measured dose without lead shielding were 7.1-2.6 cGy with $3{\times}3\;cm^2$, 8.9-3.6 cGy with $4{\times}4\;cm^2$, 12.3-4.8 cGy with $5{\times}5\;cm^2$, 14.6-5.0 cGy with $6{\times}6\;cm^2$ and 21.1~6.4 cGy with $7{\times}7\;cm^2$. As shown above, the scatted radiation decreased after using lead shielding. Depending of the range of field sizes, the resulting difference between without shielding values and with shielding values were: 7.8-1.1 cGy at 4 cm, 5.1-1.2 cGy at 5 cm, 3.8-1.1 cGy at 6 cm, 3.4-1.7 cGy at 7 cm, 2.8-1.7 cGy at 8 cm, 2.4-2.5 cGy at 9 cm and 2.1-1.8 cGy at 10 cm. In the situation as described above, the range in values depending on the distance was 7.8-1.1 cGy with $3{\times}3\;cm^2$, 6.9-1.6 cGy with $4{\times}4\;cm^2$, 5.3-0.8 cGy with $5{\times}5\;cm^2$, 5.3-1.5 cGy with $6{\times}6\;cm^2$ and 1.1-1.8 cGy with $7{\times}7\;cm^2$. Conclusion: Using the device we created to shield the testicles from scattered radiation during treatment of carcinoma of the penis, we have found that scattered radiation to the testicles is decreased by the phantom testicles, and by increasing the distance between the testicles and penis.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.20 no.3
• /
• pp.225-232
• /
• 1991

A Study was carried out to elucidate the triglyceride compositions of the red pepper seed oils harvested from two different areas. The oil was extracted from the red pepper seed with nhexane. Each triglyceride of the oil was separated by thin layer chromatography (TLC) and fractonated by reverse phase high performance liquid chromatography (HPLC) on the basis of acyl carbon numbers, and partition number group(PN) and fatty acid composition of triglyceride were analyzed by gas liquid chromatography (GLC). From the results, it was found that the red pepper seed oils of the Chungsong and Youngyang areas consisted of 14 and 18 kinds of triglycerides, respectively. The red pepper seed oil of the Chungsong area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=37.1%), and that of the Youngyang area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=36.3%) and (C16:0, C16:2, C18:2=8.4%), as the major triglycerides.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.5 no.4
• /
• pp.358-369
• /
• 1995

Surface structure and adhesion by the reaction between thin metal films and SiC were studied at temperatures between 550 and $1450^{\circ}C$ for various times. The reaction with the formation of various silicides was initially observed above $850^{\circ}C$ for SiC/Co system and $650^{\circ}C$ for SiC/Ni system. The cobalt reacted with SiC and consumed completely at $1050^{\circ}C$ for 0.5 h and the nickel at $950^{\circ}C$ for 2 h. The observed CoSi phase in SiC/Co and Ni$_2$Si phase in SiC/Ni are thermodynamically stable in the reaction zone up to 125$0^{\circ}C$ and $1050^{\circ}C$ respectively. Carbon was crystallized as graphite above $1450^{\circ}C$ for SiC/Co reaction surface and $1250^{\circ}C$ for SiC/Ni. The critical loads of the thin metal films on SiC substrate were qualitatively compared in terms of the scratch test method. At temperatures between 850 and $1050^{\circ}C$, relatively higher values of 20~33 N were observed for SiC/Ni couples.

• Journal of the Korean Ceramic Society
• /
• v.30 no.1
• /
• pp.46-54
• /
• 1993

$\beta$-SiC was chemically vapor deposited by pyrolysis of MTS＋H2 gas mixture. The experiments were conducted in the temperature range of 1100~150$0^{\circ}C$ with a r.f. induction furnace under atmospheric pressure. The IR, XRD, EDS and AES analysis revealed that the free Si was always codeposited with SiC below 140$0^{\circ}C$, regardless of the total flow rate and MTS concentration, whereas $\beta$-SiC single phase was deposited at 150$0^{\circ}C$. C3H8 or CH2Cl2 as an excess C sources, was supplied with MTS in order to obtain stoichiometric SiC at low temperature. With the addition of C3H8 or CH2Cl2, the deposition rate was increased and $\beta$-SiC single phase could be deposited even at temperature as low as 110$0^{\circ}C$. In the absence of C3H8 or CH2Cl2, the microhardness of the layer was quite low (

• Transactions on Electrical and Electronic Materials
• /
• v.9 no.3
• /
• pp.101-104
• /
• 2008

The electrical properties and microstructure of nitrogen-doped poly 3C-SiC films were studied according to different thickness. Poly 3C-SiC films were deposited by LPCVD(low pressure chemical vapor deposition) at $900^{\circ}C$ and 4 Torr using $SiH_2Cl_2$ (100 %, 35 sccm) and $C_2H_2$ (5 % in $H_2$, 180 sccm) as the Si and C precursors, and $NH_3$ (5 % in $H_2$, 64 sccm) as the dopant source gas. The resistivity of the 3C-SiC films with $1,530{\AA}$ of thickness was $32.7{\Omega}-cm$ and decreased to $0.0129{\Omega}-cm$ at $16,963{\AA}$. In XRD spectra, 3C-SiC is so highly oriented along the (1 1 1) plane at $2{\theta}=35.7^{\circ}$ that other peaks corresponding to SiC orientations are not presented. The measurement of resistance variations according to different thickness were carried out in the $25^{\circ}C$ to $350^{\circ}C$ temperature range. While the size of resistance variation decreases with increasing the films thickness, the linearity of resistance variation improved.

• Journal of Sensor Science and Technology
• /
• v.17 no.5
• /
• pp.325-328
• /
• 2008

This paper describes the electrical properties of poly (polycrystalline) 3C-SiC thin films with different nitrogen doping concentrations. In-situ doped poly 3C-SiC thin films were deposited by APCVD at $1200^{\circ}C$ using HMDS (hexamethyildisilane: $Si_2(CH_3)_6)$) as Si and C precursor, and $0{\sim}100$ sccm $N_2$ as the dopant source gas. The peak of SiC is appeared in poly 3C-SiC thin films grown on $SiO_2/Si$ substrates in XRD(X-ray diffraction) and FT-IR(Fourier transform infrared spectroscopy) analyses. The resistivity of poly 3C-SiC thin films decreased from $8.35{\Omega}{\cdot}cm$ with $N_2$ of 0 sccm to $0.014{\Omega}{\cdot}cm$ with 100 sccm. The carrier concentration of poly 3C-SiC films increased with doping from $3.0819{\times}10^{17}$ to $2.2994{\times}10^{19}cm^{-3}$ and their electronic mobilities increased from 2.433 to $29.299cm^2/V{\cdot}S$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.11a
• /
• pp.45-45
• /
• 2009

This paper describes the formation of porous 3C-SiC by anodization. 3C-SiC thin films were deposited on p-type Si(100) substrates by APCVD using HMDS (Hexamethyildisilane: $Si_2(CH_3)_6$). UV-LED(380 nm) was used as a light source. The surface morphology was observed by SEM and the pore size was increased with increase of current density. Pore diameter of 70 ~ 90 nm was achieved at 7.1 $mA/cm^2$ current density and 90 sec anodization time. FT-IR was conducted for chemical bonding of thin film and porous 3C-SiC. The Si-H bonding was observed in porous 3C-SiC around wavenumber 2100 $cm^{-1}$. PL shows the band gap enegry of thin film (2.5 eV) and porous 3C-SiC (2.7 eV).