• Journal of Communications and Networks
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• v.14 no.1
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• pp.1-9
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• 2012

We consider a receiving node, located at the origin, and a Poisson point process (PPP) that models the locations of the desired transmitter as well as the interferers. Interference is known to be non-Gaussian in this scenario. The capacity bounds for additive non-Gaussian channels depend not only on the power of interference (i.e., up to second order statistics) but also on its entropy power which is influenced by higher order statistics as well. Therefore, a complete statistical characterization of interference is required to obtain the capacity bounds. While the statistics of sum of signal and interference is known in closed form, the statistics of interference highly depends on the location of the desired transmitter. In this paper, we show that there is a tradeoff between entropy power of interference on the one hand and signal and interference power on the other hand which have conflicting effects on the channel capacity. We obtain closed form results for the cumulants of the interference, when the desired transmitter node is an arbitrary neighbor of the receiver. We show that to find the cumulants, joint statistics of distances in the PPP will be required which we obtain in closed form. Using the cumulants, we approximate the interference entropy power and obtain bounds on the capacity of the channel between an arbitrary transmitter and the receiver. Our results provide insight and shed light on the capacity of links in a Poisson network. In particular, we show that, in a Poisson network, the closest hop is not necessarily the highest capacity link.

• Journal of the Korean GEO-environmental Society
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• v.14 no.10
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• pp.59-64
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• 2013

Effects of weathering intensity on the adsorption of heavy metals such as lead(Pb) and copper(Cu) onto decomposed granite soils were investigated by a series of batch tests. The chemical components such as $SiO_2$, $K_2O$ and $Na_2O$ having relatively high solubility were reduced and the oxidized $Fe_2O_3$ content was increased with the increase of weathering intensity. Weathering of granite soils increased the ignition loss and specific surface area, while it decreased the permeability. The lead and copper adsorptions onto the decomposed granites were enhanced with the increase of weathering intensity, mainly due to the increase of specific surface area and clayed contents. Adsorption of lead and copper onto the weathered granites could be more adequately described by the pseudo-second-order kinetic model than the pseudo-first-order model.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.481-492
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• 2009

The characteristic of cold water by upwelling in the southeast of the Korean Peninsula and the effect of sea breeze in this region are investigated. The coastal upwelling around the southeast coast of the Korea Peninsula is analyzed by using Coastal Oceanographic Data statistical analyses for 5 years were carried out. The period of an cold water event, on the average, was observed southwesterly wind events. The analysis suggests that strong and persistent southwesterly winds in period of an cold water play an important role of bring the moisture to the surface, generating persistent cyclone as jangma. In order to investigate the effect of cold water on sea breeze, we considered two case. First, Exp. 1 is not occurred coastal upwelling on sea breeze. Second, Exp. 2 is occurred cold water on sea breeze. Two experiments were completed separately to the effects of cold water by upwelling. The results show the sea breeze is stronger in Exp. 2, when the cold water occurs, and weaker in Exp. 1, when there is no cold water. In order to verify the effect of the sea breeze on the cold water by upwelling, on the intensification and change of direction of the prevailing wind, the sea breeze effectively intensify cold water condition.

• Journal of Magnetics
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• v.18 no.1
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• pp.34-38
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• 2013

This paper studies the effects of the Mn-site substitution by nickel on the magnetic properties and the magnetocaloric properties of $La_{0.7}Ca_{0.3}Mn_{1-x}Ni_xO_3$ (x = 0, 0.05 and 0.1). The orthorhombic crystal structures of the samples are confirmed by the room temperature X-ray diffraction. The dependence of the Curie temperature ($T_C$) and the magnetic entropy change (${\Delta}S_M$) on the Ni doping content was investigated. The samples with x = 0 had the first order phase transition, while the samples with x = 0.05 and 0.1 had the second order phase transition. As the concentration of Ni increased, the maximum entropy change (${\mid}{\Delta}S_M{\mid}_{max}$) decreased gradually, from 2.78 $J{\cdot}kg^{-1}{\cdot}K^{-1}$ (x = 0) to 1.02 $J{\cdot}kg^{-1}{\cdot}K^{-1}$ (x = 0.1), in a magnetic field change of 15 kOe. The measured value of $T_C$ was 185 K, 150 K and 145 K for x = 0, 0.05 and 0.1, respectively. The phase transition temperatures became wider as x increased. It indicates that the Mn-site substitution by Ni may be used to tailor the Curie temperature in $La_{0.7}Ca_{0.3}Mn_{1-x}Ni_xO_3$.

• Journal of Fashion Business
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• v.22 no.5
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• pp.1-14
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• 2018

The purpose of this study was to define the purchase behavior of online luxury fashion brand consumers that soon became new luxury consumption trends. To investigate online luxury fashion brand consumer's purchase behavior, three variables were suggested based on advanced researches. These variables include economic value, item variety and pleasure. Purchasing luxury online was not common but as cross-border online shopping market became popular, consumers began to purchase luxury items through online shopping platforms. Preliminary surveys was conducted on 20~40-year-old consumers who have experience in online shopping for luxurious items. Total 238 questionnaires were used for analysis. By using SPSS, frequency analysis, factor analysis, reliability analysis, correlation analysis, regression analysis, t-test and ANOVA were conducted. The results of the study were as follow; first, consumer's purchase behavior appeared to be influenced by the order of pleasure of shopping, economic value and item variety. Repurchase intention appeared to be affected by the order of economic value, item variety, and pleasure of shopping. Second, online luxury fashion consumers perceived that risk does not affect purchase intention and repurchase intention. Third, as purchase intention increases, repurchase intention also increases. Fourth, shopping value, age and channel risk also indicated meaningful differences. As an early study of luxury fashion brand products purchased directly online, the academic significance can facilitate an overall understanding of consumer behavior such as usage motive, risk perception, behavioral intention.

• Journal of Digital Convergence
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• v.18 no.12
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• pp.363-375
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• 2020

This study attempted to verify the structural model of the influence of parental intimacy, parental supervision, peer pressure, and TV alcohol advertising on drinking behavior for adolescents. It was conducted through a self-written questionnaire from May 1 to 28, 2019, targeting 602 students in grades 1 to 3 of 8 middle schools in G city. Results First, The direct effect on drinking behavior was in the order of peer pressure and TV alcohol advertisement, and they explained the degree of drinking behavior by 14.4%. second, Parental intimacy has an indirect effect on peer pressure and drinking behavior through TV alcohol advertising. Parental supervision has an indirect effect on drinking alcohol through TV alcohol advertisements. In multiple groups, there is a difference between the groups in the parental supervision and peer pressure, and the parental supervision and the channel coefficient of TV alcohol advertisement. In order to reduce drinking behavior, a realistic light that can cope with peer pressure is needed.

• The Journal of Industrial Distribution & Business
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• v.12 no.2
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• pp.29-40
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• 2021

Purpose: In this study, with the transaction amount of foreign direct Purchase and foreign direct sales increasing, South Korea is in a situation where foreign direct sales are focused on China. We looked at the impact of consumer innovation and site characteristics on repurchase ability among the characteristics of overseas direct purchase consumers as a way to make direct overseas sales to various overseas countries. Research design, data and methodology: Consumer innovativeness consists of four variables: functional, hedonistic, social, and cognitive, and the site characteristics consisted of four variables: product price, product assortment, convenience, and service. The study was conducted on consumers with foreign direct purchase experience, and was finally used in 252 additional analyses. Results: The main findings of this study were first, that the impact on the degree of re-purchase among consumer innovativeness of foreign direct purchase consumers had a significant impact in the order of cognitive innovativeness, hedonistic innovativeness, and functional innovativeness. Social innovativeness did not affect the degree of re-purchase. Second, site characteristics have been found to have a significant impact on the degree of re-purchase in order of product assortment, commodity price, and service. Convenience did not affect the degree of re-purchase. Conclusions Taken together these results can be called the biggest characteristic of the cognitive innovativeness of the consumer's inclination to use the overseas direct purchase, the price or quick response of the goods sold on the site is a factor that affects the re-purchase, above all it is important to have a variety of products. We will present this element as a way to make direct sales abroad to various countries. In addition, foreign direct purchase is a lot of transactions in China, the United States, EU, but the share of China is high in foreign direct sales, and the U.S. and EU have a very low performance, it is important to consider the reasons why they prefer Korean products in China to study the social and cultural characteristics of U.S. and European consumers in the future, and to support and active marketing that companies and sellers can increase sales.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.345-356
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• 2021

In order to increase the structural stability of existing caisson breakwater, the design and the construction is carried out by installation of new caissons on the back or the front of old caissons. In this study, we use the ANSYS AQWA program to analyze the wave forces acting on individual caisson according to effects of wave structure interaction when new caissons are additionally installed on existing caisson breakwater. Firstly, the wave force characteristics acting on the individual caisson were analyzed for each period (frequency) in the frequency domain. In time domain analysis, the dynamic wave force characteristics were strongly influenced by the distance between caissons on the frequency at which the unusual distribution of wave forces occurs.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.483-492
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• 2021

This study evaluated the removal efficiencies of methylene blue (MB) and humic acids (HA) using a rice husk (RH) biochar and powdered activated carbon (PAC). The pseudo-second-order model better presented the adsorption of MB and HA onto a RH biochar than the pseudo-first-order model. Furthermore, better description of the adsorption behavior of MB and HA by the Langmuir isotherm model (R² of the RH biochar: MB = 0.986 and HA = 0.984; R² of PAC: MB = 0.997 and HA = 0.989) than the Freundlich isotherm model (R² of the RH biochar: MB = 0.955 and HA = 0.965; R² of PAC: MB = 0.982 and HA = 0.973) supports the assumption that monolayer adsorption played key roles in the removal of MB and HA using the RH biochar and PAC. Batch experiments were performed on the effects of dosage, temperature, and pH. For all experiments, PAC showed higher efficiencies than RH biochar and MB adsorption efficiencies were higher than those of HA. Adsorption efficiencies increased with increasing amounts of adsorbents and temperature. As the pH increased, adsorption efficiencies of MB were increased while adsorption efficiencies of HA were decreased.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.715-727
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• 2021

This research is to investigate the concept of Local Housing Association, and stepwise implementation procedure, through the theoretical consideration, and then to find out overall problems happening in the process of pushing ahead with Local Housing Association, including problems in the corresponding business stage, based on the cases of Local Housing Association that have been appearing in Changwon areas, Gyeongnam, and to present legal and policy directions for solutions to it, based on it. First, regarding improvement measures at the stage of promotion committee, it is necessary to introduce the system to report the establishment of promotion committee to cities, provinces, and districts under the jurisdiction of the location of overall business, for the establishment of association. In order to secure the professionalism of promotion committee, it is necessary to enforce those members to receive education and training for a certain period, and improve the system to post on Website or through public notices. Second, regarding improvement measures at the stage of the approval of establishment, Local Housing Association have difficulties in replacing members and joining new memberships, after getting the approval of the establishment, which can put the brake on business operation. Finally, in order to prevent crime actions, such as embezzlement or breach of duty, in advance, it is necessary to establish the institutional system that allows every member to check details of business fund. It is expected that this research would minimize side effects incurred by Local Housing Association System and help Local Housing Association take full institutional responsibility and play an axis of housing supply policy.