• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.67-79
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• 2020

Plans to mitigate overheating in urban areas requires the identification of the characteristics of the thermal environment of the city. The key information is the distribution of higher and lower temperatures (referred to as "hotspot" or "coldspot", respectively) in the city. This study aims to identify the areas within Jeonju City that are suffering from increasing land surface temperatures (LST) and the factors linked to such this phenomenon. To identify the hot and cold spots, Local Moran's I and Getis-Ord Gi^* were calculated for the LST based on 2017 images taken using the thermal band of the Landsat 8 satellite. Hotspot analysis revealed that hotspot regions, (the areas with a high concentration of Land Surface Temperature) are located in the old town area and in industrial districts. To figure out the factors linked to the hotspots, a correlation analysis, and a regression analysis taking into account environmental covariates including Normalized Difference Vegetation Index (NDVI) and land cover. The values of NDVI showed that it had the strongest effect on the lowering LSTs. The results of this study are expected to provide directions for urban thermal environment designing and policy development to mitigate the urban heat island effect in the future.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.5_6
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• pp.249-256
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• 2007

GPS(generalized processor sharing) is a fair scheduling scheme that guarantees fair distribution of resources in an instantaneous manner, while virtual clock pursues fairness in the sense of long-term. In this paper, we notice that the degree of memorylessness is the key difference of the two schemes, and propose a unified scheduling model that covers the whole spectrum of history-sensitiveness. In this model, each application's resource right is represented in a value called deposit, which is accumulated at a predefined rate and is consumed for services. The unused deposit, representing non-usage history, gives the application more opportunity to be scheduled, hence relatively enhancing its response time. Decay of the deposit means partial erase of the history and, by adjusting the decaying rate, the degree of history-sensitiveness is controlled. In the spectrum, the memoryless end corresponds GPS and the other end with full history corresponds virtual clock. And there exists a tradeoff between average delay and long-term fairness. We examine the properties of the model by analysis and simulation.

• Journal of Korean Society of Transportation
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• v.34 no.3
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• pp.278-290
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• 2016

Maximum traffic flow rate is an important performance measure of operational status in transport networks, and has been considered as a key parameter for transportation operation since a bottleneck in congestion decreases maximum traffic flow rate. Although previous studies for traffic flow analysis have been widely conducted, a detection method for changes in dynamic traffic flow has been still veiled. This paper explores the dynamic traffic flow detection that can be utilized for various traffic operational strategies. Turning point analysis (TPA), as a statistical method, is applied to detect the changes in traffic flow rate. In TPA, Bayesian approach is employed and vehicle arrival is assumed to follow Poisson distribution. To examine the performance of the TPA method, traffic flow data from Jayuro urban expressway were obtained and applied. We propose a novel methodology to detect turning points of dynamic traffic flow in real time using TPA. The results showed that the turning points identified in real-time detected the changes in traffic flow rate. We expect that the proposed methodology has wide application in traffic operation systems such as ramp-metering and variable lane control.

• Journal of Korean Society of Transportation
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• v.32 no.3
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• pp.227-238
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• 2014

There is no question that railroad investment is crucial for better transport systems and the Korean government has continued to invest in railroad facilities. Nevertheless, the modal share of railroad, in particular, for freight has decreased. This is because rail freight transport can hardly meet customer needs such as just-in-time(JIT), a door-to-door service, compared to road transport, to be specific, trucking which can directly carry the freights to the final destinations. This has made the value of the railroad infrastructure less, which has been operated for the past 114 years. This study proposes a new freight movement concept called Piggy Back System. This system can carry freight trucks on the trains and deliver the freights to the final destinations. It can make a door-to-door deliver system possible for railroad transportation, which is the key factor for modal shift from road to railroad. For implementing this, this study proposes three important things: the cost-efficient reforming way of railroad yard that has been used for the past 114 years, the diagram plan of train services, and some technical reviews like clearance limits. This is the first study with practical proposals and solutions on this topic in Korea. The suggestions of this study cut down distribution costs by more than seven trillion won.

• Journal of the Korean association of regional geographers
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• v.17 no.1
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• pp.17-39
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• 2011

As recent inflows of foreign immigrants to relatively advanced countries in Northeast Asia have rapidly increased, Japan in particular uses 'multicultural coexistance' as a key concept for developing both discourse and policies on them. This paper is first of all to suggest a new typology of multicultural societies in the world ill order to differentiate the case of Northeast Asian countries from those of Western countries. And this paper is to suggest that foreign immigrants in Japan have different positions in labor markets and living experiences according to historical and social backgrounds as well as their nationality. The transformation process towards multicultural society is not only historical and social but also geographical and spatial, as foreign immigrants have made different spatial distribution and regional segregation in types. In order to control this socio-spatial process towards multicultural society, Japan has developed the concept of 'multicultural coexistence' similar with that of multiculturalism in Western countries. This concept seems to be quite significant as it has been initiated by local communities for symbiotic relationship between foreign immigrants and native Japanese dwellers. But it can be regarded as a strategic ideology to control foreign immigrants as it targets mainly on Nikkeijin, and is usually concerned with the cultural aspect. Seen from a theoretical point of view, this concept can be seen as closed with liberal multiculturalism as opportunity equity, but far from corporative multiculturalism as outcome equity, and it is on the process transferring from the first stage of tolerance to the second stage of legislation of nondiscrimination, while being distant from the third stage of legislation paradigmization of recognition, and hence appears to be easily reverted to assimilationism.

• Journal of Broadcast Engineering
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• v.14 no.2
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• pp.144-153
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• 2009

Recently, as the necessity of a light-weighted video encoding technique has been rising for applications such as UCC(User Created Contents) or Multiview Video, Distributed Video Coding(DVC) where a decoder, not an encoder, performs the motion estimation/compensation taking most of computational complexity has been vigorously investigated. Wyner-Ziv coding reconstructs an image by eliminating the noise on side information which is decoder-side prediction of original image using channel code. Generally the side information of Wyner-Ziv coding is generated by using frame interpolation between key frames. The channel code such as Turbo code or LDPC code which shows a performance close to the Shannon's limit is employed. The noise model of Wyner-Ziv coding for channel decoding is called Virtual Channel Noise and is generally modeled by Laplacian or Gaussian distribution. In this paper, we propose a Wyner-Ziv coding method based on the frequency-adaptive channel noise modeling in transform domain. The experimental results with various sequences prove that the proposed method makes the channel noise model more accurate compared to the conventional scheme, resulting in improvement of the rate-distortion performance by up to 0.52dB.

• Journal of Biomedical Engineering Research
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• v.38 no.1
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• pp.43-48
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• 2017

Chemotherapy, radiation therapy, and surgery are major methods to treat cancer. However, current cancer treatments report severe side effects and high recurrences. Recent studies about engineering nanoparticles as a drug carrier suggest possibilities in terms of specific targeting and spatiotemporal release of drugs. While many nanoparticles demonstrate lower toxicity and better targeting results than free drugs, they still need to improve their performance dramatically in terms of targeting accuracy, immune responses, and non-specific accumulation at organs. One possible way to overcome the challenges is to make precisely controlled nanoparticles with respect to size, shape, surface properties, and mechanical stiffness. Here, we demonstrate $500{\times}200nm$ discoidal polymeric nanoconstructs (DPNs) as a drug delivery carrier. DPNs were prepared by using a top-down fabrication method that we previously reported to control shape as well as size. Moreover, DPNs have multiple payloads, poly lactic-co-glycolic acid (PLGA), polyethylene glycol (PEG), lipid-Rhodamine B dye (RhB) and Salinomycin. In this study, we demonstrated a potential of DPNs as a drug carrier to treat cancer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.294-302
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• 2020

In a genetic algorithm, computer simulations are performed based on the natural evolution process of life, such as selection, crossover, and mutation. The genetic algorithm searches the approximate optimal solution by the parallel arrangement of Schema, which has a short definition length, low order, and high adaptability. This study examined the possibility of improving the efficiency of the optimal solution by considering the characteristics of the building block hypothesis, which are one of the key operating principles of a genetic algorithm. This study evaluated the efficiency of the optimization results according to the gene sequence for the implementation in solving problems. The optimal design problem of the water pipe was selected, and the genetic arrangement order reflected the engineering specificity by dividing into the existing, the network topology-based, and the flowrate-based arrangement. The optimization results with a flowrate-based arrangement were, on average, approximately 2-3% better than the other batches. This means that to increase the efficiency of the actual engineering optimization problem, a methodology that utilizes clear prior knowledge (such as hydraulic properties) to prevent such excellent solution characteristics from disappearing is essential. The proposed method will be considered as a tool to improve the efficiency of large-scale water supply network optimization in the future.

• Journal of the Korean Regional Science Association
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• v.33 no.2
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• pp.3-23
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• 2017

This study aims to understand how human capital is related to the inter-regional wage gap between the capital region and the non-capital region in Korea. We focus more specifically on whether the inter-regional wage gap is due to high levels of human capital in the capital region or due to high returns to human capital in the capital region. The decomposition method based on the unconditional quantile regression was used to examine how the relationship between human capital and the inter-regional wage gap varies along the wage distribution. When first estimating earnings functions from the two regions to apply this decomposition method, we included not only conventional indicators of human capital, such as education and on-the-job training, but also occupational skills including cognitive-interactive skills, technical skills, and physical skills. As a result, other things being equal, a large part of the inter-regional wage gap was explained by the human capital variables. Although the composition effect of the human capital variables existed in all the wage quantiles, the more important factor was the wage structure effect of the human capital variables. In addition, among the various human capital variables, the wage structure effect of years of education was a key factor in explaining the inter-regional wage gap. This study is meaningful in that it shows that the relationship between human capital and the inter-regional wage gap may vary depending on the wage quantiles.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.477-502
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• 2007

The Aconitum alboviolaceum Kom. complex includes four controversial species described from Korea; A. albouiolaceum, A. pseudolaeue, A. longecassidatum, and A. quelpaertense. The main objective of this study was to determine the taxonomic identities and systematic relationships among the species in the A. albouiolaceum complex based on morphology, numerical analyses and DNA sequence analysis. In the present study, variations in the principal morphological characters and chloroplast DNA noncoding region sequences (psbA-trnH IGS, trnL intron, and trnL-trnF IGS) were examined for 95 individuals from 20 populations. Also, neighbor-joining analysis was adopted to infer their relationships. Morphological variation appeared to be considerably high but not to be related to geographic distribution. These morphological results suggest that reevaluation of key morphological characters are needed for the proper taxonomic treatment of the complex. The length of psbA-trnH IGS region ranged from 241 to 250 bp, that of the trnL intron from 526 to 532 bp, and that of the trnL-trnF IGS region from 466 to 472 by in all taxa. Nine haplotypes were recognized from the analysis. Seven populations shared more than two haplotypes, while other thirteen populations shared only one haplotype. In the phylogenetic analysis, the nine haplotypes formed four groups, separated A. sibiricum, one of the sister groups of the complex. There also was no distinct grouping pattern supporting the species and populations observed. These results suggest that introgression or speciation might have been involved in the formation of taxa of A. alboviolaceum complex.