• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.05a
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• pp.85-87
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• 1993

We have investigated three polyene systems, $X-(-HC=CH-)_n-Y$, where X/Y=H/H, $F/CH_3$, and $NH_2/NO_2$. We estimated asymptotic values (for $n=\infty$ of the electronic properties with $logA=a_o+a_1/(n+1)+a_2/(n+1)^2+a_3/(n+1)^3$, so that the cases n=0 can be included in that equation. Here, A can be $\mu$, $\beta$, $\alpha/(n+1)$ or $\gamma/(n+1)$. For these asymptotic values. the SCF results are more reliable due to the higher level of theory, while the PM3 results can give better trend with more data for polyene systems with longer chain length.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.238-239
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• 2006

본 논문은 게이트 절연막에 OTS(n-octadecy trichlorosilance) 혼합용액을 이용하여 SAMs(Self-Assembled Monolayers)막을 형성하였다. OTS 혼합용액은 OTS를 0.1w%와 0.5w% 각각을 클로로포름 30w%와 헥산 70w%에 혼합하여 만들었다. 이 혼합용액을 게이트 절연막위에 표면처리하였다. 활성층인 Pentacene이 게이트 절연막 위에 증착될 때, OTS 혼합용액의 비에 따라 누설전류특성을 보았다. OTS를 0.1w% 처리한것이 0.5w%보다 누설전류가 더 작게 나타났다. 결과적으로 OTFT의 게이트 절연막의 절열특성은 향상시키는데 OTS 혼합용액의 비가 큰 영향을 준다.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.255-260
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• 2003

Most of the fatigue test were achieved in fully reversed condition that mean stress is zero. But, generally, mean stress can not be zero. This research was achieved the bending fatigue test that changes mean stress to spring steel and was studied relation with the mean stress and the fatigue life. The method to search effect about mean stress was extended S-N graph in two cases. One method was extended S-N graph using modified Miner's rule with considering damage. Another was extended using tendency of S-N graph. The exponential value(${\alpha}$) of mean stress-alternating stress equation is converged between the Goodman's and the Gerber's value even if fatigue life increases.

• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.113-128
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• 2005

We propose a modified version of 'a Lazy Version of Eppstein's k shortest paths Algorithm(LVEA)' which can find the k shortest paths in total time O(m+ n log n+ K log K) in the worst-case. The algorithm we propose, since the Link repeated paths are all eliminated when enumerating k shortest paths, is No link repeated paths algorithm that is suitable in a transportation network.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11C
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• pp.1581-1591
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• 2004

In this paper, we investigate the design of three low-complexity joint estimation algorithms(LJEAs) for frequency offset and carrier phase. The proposed LJEAs are based on the interpolation technique of correlation values of the received signal in frequency and phase domains. With these algorithms, the estimation ranges $\Delta$f$_{d}$${\times}$T$_{s}$ . are less than 1/2N$_{s}$ , and 1/N$_{s}$ which are comparable to conventional algorithms. The Proposed LJEAs require only 2N$_{s}$ or 4N$_{s}$ complex multiplications which are very simple compared with the conventional algorithms. Nevertheless the estimation accuracies of the LJEAs are as good as those of the conventional algorithms. Suitable areas of application include joint estimation of frequency offset and carrier phase in burst-mode digital transmission such as satellite communications.

• Journal of Ginseng Research
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• v.31 no.4
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• pp.175-180
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• 2007

To evaluate whether there is a relation between Korean red ginseng (KRG)-intake and the suppression of immune hyperactivation in HIV-1-infected patients, we measured serum soluble CD8 (sCD8) over 31-48 months in 168 patients. They were divided into four groups; HIV-1-infected control (n = 49), zidovudine (ZDV) group (n = 22), KRG group (n = 48), and combination of KRG and ZDV group (n = 49). In control, sCD8 and the ratio of sCD8/CD8+ T cells significantly increased by 33% (paired t-test, P < 0.05) and 54% over $21\;{\pm}\;13$ months (P < 0.001), respectively. In ZDV group, sCD8 decreased within first 6 months and then showed steady increase and the ratio also increased over $19\;{\pm}\;10$ months. In KRG group, sCD8 and the ratio of sCD/CD8+ T cells continuously decreased by 45% (P < 0.01) and 19% over $19\;{\pm}\;11$ months (P < 0.05), respectively. In combination group, sCD8 gradually decreased by 29% (P < 0.01). There was a clear difference in the changes in serum sCD8 over time among 4 groups. There was no rebound phenomenon in KRG group as shown in ZDV group. These results suggest that KRG-intake suppresses immune hyperactivation state by HIV antigen itself in the HIV-infected patients.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.321-326
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• 2007

An organophosphorus insecticide, chlorpyrifos, has been of a great concern due to persistence, toxicity and accumulation in soils and groundwaters. This study deals with degradation efficiency and dechlorination kinetics of chlorpyrifos by various types of zerovalent irons (ZVIs) for effective remediation of the soils contaminated with chlorinated pesticides. Chlorpyrifos degradation rate was increased with increasing ZVI treatment amount and reaction time. The degradation rate and dechlorination kinetics of chlorpyrifos increased in the order of mZVI > nZVI > cZVI in solutions and soils. Dechlorination number value of chlorpyrifos by cZVI, nZVI and mZVI treatment exhibited 1.08, 3.09 and 3.18, respectively. In soils, degradation efficiency and kinetics of chlorpyrifos significantly were affected by moisture content because of the limited contact between ZVIs and chlorpyrifos. These results suggest that nanosized and functionalized mZVI could be effectively applied to degradation of chlorinated pesticides in the soil and aqueous environments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.3
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• pp.609-616
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• 2014

Large linear span makes difficult to predict, so this study is important to the security and code system. It has been studied about the non-linear binary sequences having low correlation values and large linear span. In this paper we analyze the linear span of $S^r_a(t)=Tr^m_1\{[Tr^n_m(a{\alpha}^t+{\alpha}^{dt})]^r\}$ ($a{\in}GF(2^m)$, $0{\leq}t{\leq}2^m-2$) where n=2m and $d=2^{m-2}(2^m+3)$.

• Journal of Veterinary Clinics
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• v.30 no.6
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• pp.435-441
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• 2013

This retrospective study evaluated the effects of the interval from calving to first insemination (ICFI) and days open (DO) on the reproductive performance in dairy cows. In the first analysis, data from 705 cows were grouped based on the ICFI: short (30-60 days, n=217), medium (61-90 days, n=309), and long (91-150 days, n=179). The occurrence of endometritis was greater in the long group than in short and medium groups (p<0.05). The occurrence of ovarian cysts increased with increasing ICFI (p<0.05), while body condition score (BCS) during the 5 month postpartum period was lower with increasing ICFI (p<0.01). The hazard of pregnancy by 365 days in milk (DIM) was lower (hazard ratio [HR]=0.70, p<0.0001) in the long group, but higher (HR=1.41, p<0.0001) in the short group compared with the medium group. In the second analysis, data from 436 cows were grouped based on the DO: short (30-90 days, n=154), medium (91-180 days, n=183), and long (181-360 days, n=99). The occurrence of a retained placenta was greater in the long group than in the medium group (p < 0.05). Ovarian cysts occurred more frequently in medium and long groups than in the short group (p=0.08). BCS was lower in the short group compared with medium and long groups at month 1 postpartum (p<0.05). Milk yield (kg/day) was greater in the medium group compared with the short group at months 2 to 5 postpartum (p<0.05). The hazard of first insemination by 150 DIM was lower in the long group than in the short group (HR=0.73; p<0.02). The hazard of pregnancy by 365 DIM was lower (HR=0.64, p<0.0001) in the long group than in the medium group, while the hazard did not differ between short and medium groups (p>0.05). Moreover, the culling rate was greater in the long group than in the short group (p<0.05). In conclusion, a longer ICFI and DO resulted in reduced reproductive performance in dairy cows, which was attributable to an increase in postpartum diseases, a lower BCS and a greater milk yield.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.295-303
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• 2005

The sexual dimorphism and intra sexual dimorphism in males of Rhinogobius brunneus were investigated at Jiam stream, a tributary of the Bukhan river from May, 2005. The frequency distributions in standard length were similar for the females and maleLs, but maleSs were smaller than the females and maleLs. The ratio of MaleL (N=79) to males (N=79) was 1 : 0.46. The comparison between female (N=79) and maleL (N=79) gave significant differences (P<0.05) in 18 morphometric characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, ED, HL, FDFL, SDFB, CFL, AFB, VFL, PFL, PFB) and 12 characteristics (SNL, AHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFI, CFL, PFB) (P<0.001). Eight morphometric characteristics (SNL, ML, DL, MW, HL, CFL, VFL, PFL) in female (N=36) and males (N=36) had significant differences (P<0.05) and three characteristics (ML, DL, HL) had very significant differences (P<0.001). Eleven characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFL) were significantly different in maleL (N=36) and males (N=36) (P<0.05) and six (ML, DL, MW, AHW, HL, FDFL) were very significantly different (P<0.001).