• Journal of IKEEE
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• v.15 no.4
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• pp.281-286
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• 2011

DVB-T2 is a next generation DTV transmission standard, which supports various channel bandwidths. Since the symbol rate of the DVB-T2 signal is changed according to its bandwidth, the received signal needs to be sampled at a different frequency. The sampling frequency should be also adjusted depending on the sampling frequency offset due to the frequency error in the local oscillator. The sampling frequency can be locked into the symbol frequency by resampling the sampled data by ADC running at a fixed frequency. In this paper a resampler architecture for DVB-T2 is proposed. And the simulation results reveal the spectral characteristics of each subcarriers used in DVB-T2 system.

• The Korean Journal of Applied Statistics
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• v.31 no.6
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• pp.811-823
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• 2018

Multivariate control chart based on Hotelling's $T^2$ statistic is a powerful tool in statistical process control for identifying an out-of-control process. It is used to monitor multiple process characteristics simultaneously. Detection of the out-of-control signal with the $T^2$ chart indicates mean vector shifts. However, these multivariate signals make it difficult to interpret the cause of the out-of-control signal. In this paper, we review methods of signal interpretation based on the Mason, Young, and Tracy (MYT) decomposition of the $T^2$ statistic. We also provide an example on how to implement it using R software and demonstrate simulation studies for comparing the performance of these methods.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.140-148
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• 2010

The effects of the addition of either monoclinic $ZrO_2(ZrO_2(m))$ or tetragonal $ZrO_2(ZrO_2(t))$ containing 5.35[wt%] $Y_2O_3$ on the physical properties and electrical conductivity of $Al_2O_3$ were investigated. The addition of $ZrO_2$(m) and $ZrO_2$(t) increased sintered density of $Al_2O_3$. The Vickers hardness also increased as addition of $ZrO_2$(t) increased going through a maximum at 20[wt%] and the hardness of the specimens was found to be dependent on the sintered density. The addition of $ZrO_2$(t) improved the hardness of $Al_2O_3-ZrO_2$ systems and the $ZrO_2$(m) addition showed the better effect on the thermal shock property of $Al_2O_3-ZrO_2$ systems than that of the $ZrO_2$(t) addition. Above 15[wt%] addition of $ZrO_2$(t), the electrical conductivity is gradually increased with increasing applied voltage but not effects by addition of $ZrO_2$(m).

• Journal of Chest Surgery
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• v.32 no.2
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• pp.175-180
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• 1999

Background: Since 1992, we developed the technique for video endoscopic sympathectomy to treat palmar hyperhidrosis. It was soon proven to be a simple and effective therapy for essential hyperhidrosis. Compensatory hyperhidrosis, however, is the main cause of patient dissatisfaction after video-assisted thoracoscopic sympathectomy. According to many authors, initial satisfaction rate was high(94-98%), but it was declined with time (66%) due to mainly to embarrassing side effects. Material and Method: From January 1992 to February 1998, the thoracoscopic T2 sympathicotomy, T2 sympathectomy and T2-4 sympathectomy were performed in 315 patients suffering from Essential hyperhidrosis in the Department of Thoracic and Cardiovascular Surgery in the Respiratory Center of Yongdong Severance Hospital Seoul, Korea. Eighty-nine patients underwent T2 sympathicotomy, and Eighty-eight patients underwent division T2 sympathectomy. Result: All of the treated patients obtained satisfactory alleviation of essential hyperhidrosis. The global rate of compensatory sweating were ; 64.0% in T2 sympathicotomy, 73.8% in T2 sympathectomy and 87.8% in T2-4 sympathectomy. The rate of embarrassing or disabling compensatory sweating was significantly higher in T2 sympathicotomy 15.7%(14/89) and in T2 sympathectomy 32.8%(28/88) than in T2-4 sympathectomy 58.0%(80/138) with significancy in statistic analysis(p<0.05). Video- assisted thoracoscopic sympathectomy is an effective minimally invasive and effective procedure. Conclusion: We suggest that the incidence and degree of compensatory hyperhidrosis was closely related to the extent of thoracic sympathectomy.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.279-292
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• 2011

In this paper, we consider anti-periodic solutions of the following BAM neural networks with multiple delays on time scales: $$\{{x^\Delta_i(t)=-a_i(t)e_i(x_i(t))+{\sum\limits^m_{j=1}}c_{ji}(t)f_j(y_j(t-{\tau}_{ji}))+I_i(t),\atop y^\Delta_j(t)=-b_j(t)h_j(y_j(t))+{\sum\limits^n_{i=1}}d_{ij}(t)g_i(x_i(t-{\delta}_{ij}))+J_j(t),}\$$ where i = 1, 2, ..., n,j = 1, 2, ..., m. Using some analysis skills and Lyapunov method, some sufficient conditions on the existence and exponential stability of the anti-periodic solution to the above system are established.

• East Asian mathematical journal
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• v.32 no.5
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• pp.659-675
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• 2016

In this paper, we study the generalized Kirchhoff type equation in the presence of past and finite history $$\large u_{tt}-M(x,t,{\tau},\;{\parallel}{\nabla}u(t){\parallel}^2){\Delta}u+{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_0}^t}\;h(t-{\tau})div[a(x){\nabla}u({\tau})]d{\tau}\\\hspace{25}-{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_{-{\infty}}}^t}\;k(t-{\tau}){\Delta}u(x,t)d{\tau}+{\mid}u{\mid}^{\gamma}u+{\mu}_1u_t(x,t)+{\mu}_2u_t(x,t-s(t))=0.$$ Under the smallness condition with respect to Kirchhoff coefficient and the relaxation function and other assumptions, we prove the expoential decay rate of the Kirchhoff type energy.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.3
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• pp.95-102
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• 2002

Interactive hashing is a protocol introduced by Naor, Ostrovsk Venkatesan, $Yung^{[1]}$ with t-1 round complexity and $t^2$ - 1 bits communication complexity for given t bits string. In this paper, we propose more efficiently extended interactive hashing protocol with t/m- 1 round complexity and $t^2$/m - m bits communication complexity than NOVY protocol when m is a divisor of t, and prove the security of this.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.315-321
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• 2006

Sixteen somimembranosus muscles were seamed out from sixteen left carcasses. They were cut into $7{\times}10{\times}2cm$ pieces and mixed randomly. Samples were assigned to four treatments: (T1) soy-based sauce; (T2) Kimchi-based sauce; (T3) pickled shrimp-based sauce; and (T4) onion-based sauce. Each treatment was aged in plastic box at $1^{\circ}C$ for 10 days. These samples were vacuum-packaged after treatment with sauces and held in a chill at $1^{\circ}C$ for 28 days. The pH of aged port in general, was decreased significantly (p<0.05) with storage in all treatments. Its falling rate was the slowest in T4 of all treatments, while it was faster in T2 and T3 than in T4. The salinity of aged pork was decreased (p<0.05) for T2 with increased storage days, but increased (p<0.05) for T1. The salinity showed T2 to be significantly higher (p<0.05) than T1 and T4 on 1 day, but to be lower(p<0.05) than T1 on 28 day. The saccharinity of T3 was significantly higher (p<0.05) on 1 day than those of T1 and T4, but decreased (p<0.05) on 14 and 28 day. While saccharinity of T1 was significantly the lowest(p<0.05) of all treatments on 1 day and increased (p<0.05) with increased storage days. For T1 and T2, the WHC (water holding capacity) results showed higher (p<0.05) on 14 day than on 1 and 28 day. On 28 day, the WHC result showed T4 to be the highest(p<0.05) of all treatments, but T2 to be the lowest (p<0.05). On 28 day, the shear force results showed a big difference (p<0.05) among treatments, being in order of T4>T3>T2>T1. Panelists rated T1 as having higher(p<0.05) aroma, flavor and overall acceptability than other treatments.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.417-423
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• 2011

A series of new quinoxaline-based thiophene copolymers (PQx2T, PQx4T, and PQx6T) was synthesized via Yamamoto and Stille coupling reactions. The $M_ws$ of PQx2T, PQx4T, and PQx6T were found to be 20,000, 12,000, and 29,000, with polydispersity indices of 2.0, 1.2, and 1.1, respectively. The UV-visible absorption spectra of the polymers showed two distinct absorption peaks in the ranges 350 - 460 nm and 560 - 600 nm, which arose from the ${\pi}-{\pi}^*$ transition of oligothiophene units and intramolecular charge transfer (ICT) between a quinoxaline acceptor and thiophene donor. The HOMO levels of the polymer ranged from -5.37 to -5.17 eV and the LUMO levels ranged from -3.67 to -3.45 eV. The electrochemical bandgaps of PQx2T, PQx4T, and PQx6T were 1.70, 1.71, and 1.72 eV, respectively, thus yielding low bandgap behavior. PQx2T, PQx4T, and PQx6T had open circuit voltages of 0.58, 0.42, and 0.47 V, and short circuit current densities of 2.9, 5.29 and 9.05 mA/$cm^2$, respectively, when $PC_{71}BM$ was used as an acceptor. For the solar cells with PQx2T-PQx6T:$PC_{71}BM$ (1:3) blends, an increase in performance was observed in going from PQx2T to PQx6T. The power conversion efficiencies of PQx2T, PQx4T, and PQx6T devices were found to be 0.69%, 0.73%, and 1.80% under AM 1.5 G (100 mW/$cm^2$) illumination.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.189-197
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• 2004

This study investigated the effect of belly fat on the plasma lipid concentrations in rats. The results were obtained from the rats that had been fed the experimental purified diets containing 5％ corn oil (C) as the control, 5％ commercial lard (Tl), 5％ belly fat (T2), 10％ belly fat(T3), and those given diet(T4) by feeding either C or T3 alternately every 3 days for 30 days. The food intake and food efficiency were not show any significant difference among the treatments. The body weight gain tended to significantly increased when the feeding of added-belly fat in diets (p＜0.05). The plasma triacylglycerides of T3 was higher than the other treatments, and significantly elevated as the number of feeding days of the diets with the belly fat passed when compared to diet C (p＜0.05). The plasma total cholesterol of T3 showed the highest levels in the treatment groups, and was high in the order of T1, T2, T4, and there was a significant difference between the rats given the diet with belly fat and C (p＜0.05). The plasma HDL-C of T2 and T3 was showed the lowest levels in the treatment groups. The plasma HDL-C of T1, T2, T3 and T4 groups were significantly decreased as the number of feeding days of the diets with the belly fat increased when compared to diet C (p＜0.05). The plasma LDL-C and Al of T3 showed the highest levels in the treatment groups, and the levels were in order of T1, T2, T4. There was a significant difference between the groups of rats given the belly fat and C (p＜0.05). The bleeding times significantly decreased as the number of feeding days of the belly fat diets increased, and T3 showed the lowest levels, there was a significant difference among the treatment groups (p＜0.05). The whole blood clotting times of T3 showed the lowest values, and significantly decreased according to the number of days of the rats were fed the belly fat diet (p＜0.05). These results showed that frequent consumption and high intake of pork belly can elevate the plasma triacylglyceride and cholesterol levels, and also accelerate red thrombus formation because belly fat contains high levels of saturated fatty acids and cholesterol.