• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.229-229
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• 2010

With the scaling down of ultra large integrated circuits (ULSI) to the sub-50 nm technology node, the need for an ultra-thin, continuous and conformal diffusion barrier and Cu seed layer is increasing. However, diffusion barrier and Cu seed layer formation with a physical vapor deposition (PVD) method has become difficult as the technology node is reduced to 30 nm and beyond. Recent work on self-forming barrier processes using PVD Cu alloys have attracted great attention due to the capability of conformal ultra-thin barrier formation using a simple technique. However, as in the case of the conventional barrier and Cu seed layer, PVD of the Cu alloy seed layer will eventually encounter the difficulty in conformal deposition in narrow line trenches and via holes. Atomic layer deposition (ALD) has been known for its good step coverage and precise thickness control, and is a candidate technique for the formation of a thin conformal barrier layer and Cu seed layer. Conformal Cu-Mn seed layers were deposited by plasma enhanced atomic layer deposition (PEALD) at low temperature ($120^{\circ}C$), and the Mn content in the Cu-Mn alloys were controlled form 0 to approximately 10 atomic percent with various Mn precursor feeding times. Resistivity of the Cu-Mn alloy films decreased by annealing due to out-diffusion of Mn atoms. Out-diffused Mn atoms were segregated to the surface of the film and interface between a Cu-Mn alloy and $SiO_2$, resulting in self-formed $MnO_x$ and $MnSi_xO_y$, respectively. No inter-diffusion was observed between Cu and $SiO_2$ after annealing at $500^{\circ}C$ for 12 h, indicating an excellent diffusion barrier property of the $MnSi_xO_y$. The adhesion between Cu and $SiO_2$ was enhanced by the formation of $MnSi_xO_y$. Continuous and conductive Cu-Mn seed layers were deposited with PEALD into 32 nm $SiO_2$ trench, enabling a low temperature process, and the trench was perfectly filled using electrochemical plating (ECD) under conventional conditions. Thus, it is the resultant self-forming barrier process with PEALD Cu-Mn alloy film as a seed layer for plating Cu that has further potential to meet the requirement of the smaller than 30 nm node.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.6
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• pp.208-221
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• 2020

The objective of this study is to estimate and analyze the traffic density of continuous flow using the trajectory of individual vehicles and the headway of sample probe vehicles-front vehicles obtained from ADAS (Advanced Driver Assitance System) installed in sample probe vehicles. In the past, traffic density of continuous traffic flow was mainly estimated by processing data such as traffic volume, speed, and share collected from Vehicle Detection System, or by counting the number of vehicles directly using video information such as CCTV. This method showed the limitation of spatial limitations in estimating traffic density, and low reliability of estimation in the event of traffic congestion. To overcome the limitations of prior research, In this study, individual vehicle trajectory data and vehicle headway information collected from ADAS are used to detect the space on the road and to estimate the spatiotemporal traffic density using the Generalized Density formula. As a result, an analysis of the accuracy of the traffic density estimates according to the sampling rate of ADAS vehicles showed that the expected sampling rate of 30% was approximately 90% consistent with the actual traffic density. This study contribute to efficient traffic operation management by estimating reliable traffic density in road situations where ADAS and autonomous vehicles are mixed.

• The Journal of the Acoustical Society of Korea
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• v.42 no.1
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• pp.25-31
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• 2023

In order to estimate the radial speed of an underwater object so-called target with active sonar, Continuous Wave (CW) pulse is generally used, but if a target is slow and at near distance, it is not easy to estimate the radial velocity of the target due to acoustic reverberation in the ocean. In 2017, Wang et al. utilized broadband signal of two Hyperbolic Frequency Modulation (HFM) pulses, which is known as a doppler-invariant pulse, with equal frequency band and in opposite sweep directions to overcome this problem and successfully estimate the radial speed of slow-moving nearby target. They demonstrated the estimation of the radial velocity with computer simulation using the parameters of two HFM starting time differences and receiving times. However, for it uses two HFM pulses with equal frequency, cross-correlation between the two pulses negatively affect the detection performance. To mitigate this cross-correlation effect, we suggest using two different band HFM with the opposite sweep directions. In this paper, a method of radial velocity estimation is derived and simulated using two HFM pulses with the pulse length of 1 second and bandwidth of 400 Hz. Applying the suggested method, the radial velocity was estimated with approximately 6 % of relative error in the simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.136-143
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• 2016

To provide a type approval test for Ballast Water Treatment System (BWTS) of United States Coast Guard (USCG) Phase-II, this study examined the concentrating efficiency of nets for ${\geq}10{\mu}m$ and ${\leq}50{\mu}m$ sized phytoplanktonic organisms using different mesh sized nets ($5{\mu}m$ or $7{\mu}m$), different injection methods (hand breaker as semi-continuous assessment or pump as continuous assessment), and different filterability for the water volume. As a result of the t-test, the net concentrated efficiency between $5{\mu}m$ and $7{\mu}m$ mesh size was not significant (p > 0.05). The difference in the net concentrated efficiency for filtered natural water volume was not significant (p > 0.05). On the other hand, the Chl.a concentration in the continuous water injection method was significantly (p < 0.05) higher than that of semi-continuous water injection (t-test: t: -4.058). In the natural phytoplankton community, a total of 36 species were identified, including Bacillariophyta (17 species), Dinophyta (15 species), Euglenophyta (1 species), Dictyochophyta (2 species), and unidentified taxa (1 species). Among them, diatom Pseudo-nitzchia spp. was remarkably dominant. In particular, the net concentrated efficiency in all assessments was underestimated to be approximately 20-25%, which was caused by the small size Pseudo-nitzchia spp.. A width size of these genus might have passed through the $5{\mu}m$ or $7{\mu}m$ mesh size of the net. Therefore, net concentrated efficiency is dependent on the size of the observed species in natural water. This issue should be considered when determining the net volume for the type approval test of BWTS.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2151-2153
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• 2013

The history of the APOCP/APJCP goes back to 1999 when a number of interested scientists joined together to form the organization and to launch a new journal to support cancer prevention research in the Asian-Pacific area. Since the initial Founding Conference, some six General Assemblies (GAs) and ten Regional Conferences (RCs) and Special Study Sessions have been organized. Already the decisions have been made for two further GAs and at least three RCs. As of the April issue of 2013, a total of nearly 3,700 papers have already been published in regular issues of the APJCP or special supplements. With support of the Korean National Cancer Center, housing the Chief Editorial Office, the journal is now including approximately 100 papers a month. Although it experienced a set-back by reduction in the Impact Factor (IF) from 1.29 in 2010 to 0.67 in 2011, there are good grounds to expect an improvement in 2012. However, the future of the APOCP/APJCP will continue to depend on its membership, making continuous efforts to attend our conferences and submit good quality manuscripts. It is particularly important to cite papers in the APJCP wherever possible, if the wish is for an IF commensurate with our long term aims. In that sense it is up to all authors, since the journal will continue to have a very positive ploicy towards accepting papers from all countries within the Asian-Pacific, with continue to varied levels of resources. The editorial team looks forward to your considered support. The APOCP also hopes to see you in person at future meeetings, so that you have a more active voice in deciding the best way forward in our cooperative enterprise.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.359-365
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• 2013

BACKGROUND: Methane ($CH_4$) emission is calculated using the default $CH_4$ emission factor as recommended by the International Panel on Climate Change(IPCC guidelines). However, the default emission factor has been derived using including the data from other countries having different soil and environmental conditions and may not reflect the real $CH_4$ emission rates in Korea. The objective of this study was to estimate the baseline emission factor of $CH_4$ in Korean paddy soils during rice cultivation. METHODS AND RESULTS: Methane emission patterns were characterized in four different paddy soils across country for a consecutive 3 years during the rice cultivation period. Rice plants were cultivated under continuous flooding and fertilized using the recommended chemical fertilization in Korea ($N-P_2O_5-K_2O$=90-45-57kg/ha). The mean $CH_4$ emission rate was 2.32 kg $CH_4$/ha/day and the uncertainty of the investigated data was 21.7%, with a valuable error range at 1.82-2.82 kg $CH_4$/ha/day with a 95% confidence interval. CONCLUSION(S): Conclusively, the Korean paddy soils' baseline emission factor of $CH_4$ is approximately 2.32 kg $CH_4$/ha/day and can be used to estimate the $CH_4$ emissions more exactly.

• Journal of Korea Association of Health Promotion
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• v.2 no.3
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• pp.31-46
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• 2004

Owing to continuous economic growth, an increased standard of living, and improvements to health care in Korea, the life expectancy of Koreans rose from 69.0years in 1985 to 71.3 years in 1990 It continued to rise throughout the 1990s, and, by2002, had reached 76.5 years for the general population and 80.0 years for Korean females. Similarly, the percentage of the Korean population that is 65 years of age or older Increased from 3.1 In 1970 to 7.1 In 2000, and is expected to reach approximately14.0 in 2019. Thus, according to this estimate, Korea will have evolved from an 'aging society 'to an "aged society" in only 19 years. In the case of other countries, this same transformation has generally taken 2 to 5 times longer. One of the major issues related to Korea's rapid1y aging population relates to the health problems of the elderly According to the 2002 National Health Survey Report,87.6 percent of the elderly were reported to have at least one chronic disease. In other words, almost 9 out of evert 10 elderly persons in Korea were suffering from a chronic illness. This, clearly, places a significant economic burden on Korean society in the form of increased health care costs. This paper examines the increasing prevalence of chronic diseases within Korea's rapidly aging population and offers some possible short- and long-term solutions to cope with the increased burden being placed on Korea's health care system. These Include the basic services at local health centers for the elderly and the national life-long health promotion programs that aim to correct unhealthy behavior, such as smoking, the excessive use of alcohol, and poor eating and exercise habits.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.684-689
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• 2006

This study evaluated the physicochemical characteristics of domestic and imported packaged Kimchi in Korea. Six types of domestic and imported Kimchi were collected from a supermarket. According to the results, the salt concentrations of the domestic and imported Kimchi were 3.83% and 3.06%, respectively. The total lactic acid content was 0.33% for domestic Kimchi, and 0.29% for imported Kimchi. The total vitamin C content was found to be higher in the domestic Kimchi (30.9mg%) than in the imported Kimchi(25.9mg%). These results suggest that both are within the standards of the Korea Food and Drug Administration in terms of food containment: 1% or lower for acid, and $1{\sim}4%$ for salt. For the number of aerobic bacteria present in each of them, both contain approximately $10^4{\sim}10^5\;CFU/g$g, which is safely under the FDA standard of $10^7{\sim}10^8 \;CFU/g$. Therefore, neither is harmful at all in terms of the number of bacteria but continuous monitoring will be necessary. from texture analysis, the hardness and chewiness of the domestic Kimchi was better than the imported Kimchi. The hardness and chewiness of the domestic Kimchi indicated a better production process than imported Kimchi. There may not be a particular difference in terms of the sensory evaluation apart from its crispy taste. However, this also needs to be continuously monitored while the Kimchi is undergoing the fermentation process.

• Journal of Broadcast Engineering
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• v.20 no.2
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• pp.265-272
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• 2015

A new technology on video frame rate up-conversion (FRUC) is presented by combining the median filter and motion estimation (ME) with an occlusion detection (OD) method. First, ME is performed to have a motion vector. Then, the OD method is used to refine motion vector in the occlusion region. Since the wrong motion vector can be obtained with high possibility in the occluded area, a median filtering that less depends on the motion vector is applied to that area, and since the motion vector is continuous and robust in the non-occluded area, BDMC(Bi-Directional Motion Compensated interpolation) is applied to obtain interpolated image in that area. BDMC using the bi-directional motion vectors achieves good results when continuity and robustness of the motion vector is higher. Experimental results show that the proposed algorithm provides better performance than the conventional approach. The average gain of PSNR (Peak Signal to Noise Ratio) is approximately 0.16 dB in the test sequences compared with BDMC.

• Journal of Korea Game Society
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• v.2 no.1
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• pp.62-68
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• 2002

This paper presents a method for tessellating trimmed NURBS surface with preserving sharp shape Although several existing approaches need a large number of triangular meshes to represent sharp shape of surface, resulting triangular meshes may not reflect sharp edges properly. In this study, we flit detect the sharp shape of NURBS surface automatically using C1 continuous condition and then use constraint Delaunay triangulation method to present exact sharp shape with the minimum triangular meshes. And we also use approximated developed surface domain as triangulation domain of rimmed NURBS surface. In this way, the shape of triangular elements on the triangular domains is approximately preserved and can avoid distortion when mapped into three-dimensional space. finally, we show examples that demonstrate the effectiveness of the proposed scheme in terms of reducing the number of triangular meshes and preserving sharp shape of surface more exactly.