• Journal of Ginseng Research
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• v.34 no.1
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• pp.8-16
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• 2010

Attention deficit hyperactivity disorder (ADHD) affects 4-12% of chool-age children worldwide and is characterized by three core symptoms: hyperactivity, inattention, and impulsivity. Although standard pharmacological treatments, such as methylphenidate and atomoxetine, are available, concerns about drug-induced psychological and cardiovascular problems, as well as growth retardation and sleep disturbances, highlight the continuing need for new therapeutic interventions. Using a neonatal hypoxia-induced hyperactivity model in rats, the potential positive role that oral administration of red ginseng extract may have in relation to the hyperactive phenotype was investigated. Hypoxia was induced in 2-day-old male Sprague-Dawley (SD) rat pups by placing them in a nitrogen chamber for 15 min. The neonatal hypoxia-induced rats showed a significant increase in hyperactivity phenotype, such as increased movement duration, movement distance, and rearing frequency, which was determined by monitoring their spontaneous locomotor activity using the Ethovision video tracking system. One week of oral treatment with red ginseng extract decreased the hyperactivity phenotype of the neonatal hypoxia-induced rats and increased the locomotor activity of the control rats. In the neonatal hypoxia-induced rats, expression of the norepinephrine transporter in the forebrain was increased, and red ginseng treatment partially prevented its up-regulation, while increasing its level in the control rats. Taken together, these results suggest that red ginseng extract decreased the neonatal hypoxia-induced hyperactivity phenotype, although it increased locomotor activity in normal animals.

• Geomechanics and Engineering
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• v.20 no.3
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• pp.255-265
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• 2020

Laboratory tests are conducted to investigate the performance of retaining system with different combinations of long-short piles. Numerical analysis implemented using ABAQUS are verified by comparing numerical results with measured data. By performing numerical studies, the horizontal displacement of piles, heave of excavation bottom and bending moment of pile for various pile system with different pile lengths are investigated. Results show that long piles share higher bending moments than short piles. The increase in the number of short piles leads to a slight increase in the heave at excavation bottom for long-short pile retaining system. Retaining system with different long and short pile combinations have greater effects on the horizontal displacement of pile above the excavation bottom, compared to its counterparts below excavation bottom. For a given length of long pile, the bending moment and displacement of piles increase with the decrease in length of short piles, while the increasing rate of maximum moment of retaining pile system is insignificant. Results highlight that a reliable and economical pile retaining system can be designed by optimizing the number and length of short piles, provided that the working performance of retaining structures above excavation bottom meets the design requirement in practice.

• Journal of Information Technology Applications and Management
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• v.25 no.2
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• pp.53-72
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• 2018

This empirical study explored characteristics that affect the usefulness of online reviews, in the China e-commerce platform, and implemented multiple regressions to find factors that significantly influence on product sales, ultimately. Till now, prior studies have continuously revealed what factor affects usefulness of online review or product sales, only in respective terms. The point of our study is that we built two-level regression models, thereby being able to comprehensively analyze these two different targets. Before plunging into running regressions, we carefully collected 192,764 online review data for 200 products extracted from the Jingdong, the second biggest e-commerce platform in China. Also, we gathered "review sentimental scores" variable from each review and used that one as a core variable in our regression model, thus we were able to implement both quantitative and qualitative research. The evidences from the two-level regression models showed that the extent to which a product is experience good positively affects both usefulness of a review and product sales, again the usefulness of a review contributes to product sales in sequence. Also, the property of experience good has interaction effect on both for two-level regression models. Our main findings highlight the importance of role of online review to business performance of e-commerce firms.

• Asian Journal of Atmospheric Environment
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• v.2 no.2
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• pp.90-101
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• 2008

The chemical compositions of $PM_{2.5}$ and $PM_{10}$ and associated high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) were investigated during winter and summer at a roadside and an urban background site in Saitama, Japan. The average concentrations of $PM_{2.5}$ exceeded the United States Environmental Protection Agency standards during both periods. Carbonaceous components were abundant in both the observed and calculated (by means of a mass closure model) chemical composition of $PM_{2.5}$. Traffic-related pollutants (elemental carbon and high-molecular-weight PAHs) were strongly associated with $PM_{2.5}$ rather than with larger particles. The mass concentrations of $PM_{2.5}$, as well as those of EC and PAHs associated with the particles, at the two sites were strongly correlated. Comparison of our data with source profile ratios indicates that diesel-powered vehicles were probably the main source of the measured PAHs. The PAHs concentrations were affected by meteorological conditions during our study. Our results highlight the need for the establishment of standards for $PM_{2.5}$ in Japan.

• School Mathematics
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• v.18 no.3
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• pp.733-747
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• 2016

To describe mathematics learning relying on a priori assumptions about the learners has a risk of assuming the learners as well-prepared subjects. In this study we investigate the epistemological perspective of Gilles Deleuze which is expected to give overcome this risk. Then we analyze the constructivist's epistemology and prior discussions about learning mathematics in the preceding studies accordingly. As a result, a priori assumption on which students are regarded as well-prepared for learning mathematics is reconsidered and we propose a new model of thought to highlight the involuntary aspect of the occurrence of thinking facilitated by the encounter with mathematical signs. This perspective gives a new vision on involuntary aspects of mathematics learning and the learner's confusion or difficulty at the starting point of learning.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2671-2676
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• 2015

Nowadays, Mobile devices are now capable of supporting a wide range of applications. Unfortunately, some of applications demand an ever increasing computational power and mobile devices have limited resources due to their constraints, such as low processing power, limited memory, unpredictable connectivity, and limited battery life. To deal with mobile devices' constraints, researchers envision extending cloud computing services to mobile devices using virtualization techniques to shift the workload from mobile devices to a powerful computational infrastructure. Those techniques consist of migrating resource-intensive computations from a mobile device to the resource-rich cloud, or server (called nearby infrastructure). In this paper, we want to highlight on cloudlet architecture (nearby infrastructure with mobile devices), its functioning and in our future work, analyze effects of distance between cloudlet and mobile devices.

• International Journal of Quality Innovation
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• v.7 no.1
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• pp.60-89
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• 2006

In the Knowledge-based Economic Era, all of the enterprises are facing global competitive pressure. The activities of knowledge accessing, codifying, and application will obviously become the main inner function on enterprise operation. Knowledge will be the primary competitive advantage; therefore, he who wants to hold the competitive advantage should do the knowledge management (KM) very well. In this study, we construct the research dimensions and variances by the successful factors of KM, which had been practiced very well by big enterprises inside and outside our country, and which was recommended by the related scholars. In order to approach the differences between big enterprises and small and medium-sized enterprises (SMEs) towards implementing KM, this study takes the way of questionnaire investigation to do empirical analysis and to construct the model of KM by path analysis. The study found out when implementing KM, SMEs should highlight 'leadership,' 'library-architecture,' and 'corporate culture' these three aspects, while 'information technology' and 'performance evaluation' these two aspects show no remarkable influence. It shows that he who wants to construct KM might not too overweight on information technology to build the KM system. Therefore, we suggest when implementing KM, enterprises should reinforce the corporate culture by sharing, organized KM process, learning environment for all employees, and highly authorization by top managers in order to reach the expectant success of KM. The result of this study offers practical thinking directions to reach the expectant success for the policy makers in SMEs, who are accessing to or evaluating to implement KM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.431-437
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• 2017

In this study, based on the RPS algorithm, the application results to an electrically controlled suspension system using previewed road information are presented. Reducing the excessive vibration induced by a disturbance transmitted to the system and secure its stability is a major issue. In particular, in the automotive industry, the demand is constantly being raised. A typical external disturbance causing vibration and instability of a vehicle is an irregular roadway surface that contacts a running vehicle tire. Therefore, obtaining such profile information is an important process. The RPS algorithm using a multi sensor system was constructed and implemented in a real car. Through experimental work using the RPS system included non-contact type optical sensors, it could robustly reconstruct the road input profiles from the intermixed data onto the vehicle's dynamic motion while traveling at an uneven roadway surface. A controller with a preview control was designed in the framework of a semi-active suspension system based on the 7 degrees of freedom full vehicle model. The control performance of the system was evaluated through simulations and the results were compared with the passive vehicle condition. These results highlight the feasibility of the presented control frame.

• Journal of Distribution Science
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• v.17 no.1
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• pp.73-87
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• 2019

Purpose - This research aims to investigate the effects that the selection of oriental medicine cosmetics and brand asset attributes have on consumers' economic, emotional and social values in order to shed light on the forms and characteristics of consumption within the globally developing oriental medicine cosmetics market, and in the end positively verify how such perceived values affect purchase intention. In addition, it proposes research outcomes by comparing the differences between national and cultural consumer purchase behavior based on the comparisons of consumer groups in South Korea and China, the major markets for oriental medicine cosmetics. Research design, data, and methodology - Based on advanced research a total of 9 hypotheses were designed and questionnaires consisting of 16 questions to identify six major variables were conducted. Research was carried out centered on Seoul, South Korea, and its surrounding metropolitan area as well as Beijing and Shanghai, China, and a total of 577 sets of significant data were collected. A comparison analysis was then conducted on the data from 285 Koreans and 292 Chinese. A regression analysis and path analysis were also carried out based on a structural equation model to suggest results. Results - Research results show brand value assets had a more crucial impact on consumers' perceived value than consumer selection of oriental medicine cosmetics, while emotional value had a bigger effect on purchase intension than social or economic values. For Chinese consumers in particular, social, economic and emotional values affected purchase intention, while emotional value was the most crucial factor for Korean consumers. Conclusions - With oriental medicine cosmetics, brand characteristics and images that helped express emotional desire proved to be more effective in marketing than the performance aspect of cosmetics, including their functions and ingredients. In the end, products that highlight individual desire and emotion should be introduced instead of those that emphasize price, functions and social characteristics in order to expand the global market of oriental medicine cosmetics.

• Journal of Korean Medical Science
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• v.33 no.53
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• pp.341.1-341.11
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• 2018

Background: The converging epidemics of tuberculosis (TB) and end-stage renal disease (ESRD) have generated a significant public health burden, however, previous studies have been limited to a small number of patients. This nationwide cohort study aimed to assess the rate of developing active TB among patients receiving dialysis for ESRD. Methods: The Korean national health insurance database was used to identify patients receiving dialysis for new-onset ESRD during 2004-2013, who were propensity score matched to an equivalent number of non-dialysis subjects from the general population. The incidences of active TB in the ESRD and control cohorts were calculated for 2004-2013, and multivariable Cox proportional hazards model was used to evaluate the ESRD-related risk of active TB. Results: During 2004-2013, 59,584 patients received dialysis for newly diagnosed ESRD. In the dialysis and control cohorts, 457 (0.8%) and 125 (0.2%) cases of active TB were detected, respectively. Patients with ESRD were associated with a significantly higher risk of active TB compared to the controls (incidence rate ratio, 4.80). The ESRD cohort had an independently elevated risk of active TB (adjusted hazard ratio, 4.39; 95% confidence interval, 3.60-5.37). Conclusion: We found that patients receiving dialysis for ESRD had an elevated risk of active TB. These results highlight the need for detailed and well-organised guidelines for active TB screening among patients with ESRD.