• Journal of Biomedical Engineering Research
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• v.45 no.4
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• pp.179-186
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• 2024

This paper investigates the impact of Riemannian Procrustes Analysis (RPA) on enhancing the classification performance of SPD-Net when applied to EEG signals across different sessions and subjects. EEG signals, known for their inherent individual variability, are initially transformed into Symmetric Positive Definite (SPD) matrices, which are naturally represented on a Riemannian manifold. To mitigate the variability between sessions and subjects, we employ RPA, a method that geometrically aligns the statistical distributions of these matrices on the manifold. This alignment is designed to reduce individual differences and improve the accuracy of EEG signal classification. SPD-Net, a deep learning architecture that maintains the Riemannian structure of the data, is then used for classification. We compare its performance with the Minimum Distance to Mean (MDM) classifier, a conventional method rooted in Riemannian geometry. The experimental results demonstrate that incorporating RPA as a preprocessing step enhances the classification accuracy of SPD-Net, validating that the alignment of statistical distributions on the Riemannian manifold is an effective strategy for improving EEG-based BCI systems. These findings suggest that RPA can play a role in addressing individual variability, thereby increasing the robustness and generalization capability of EEG signal classification in practical BCI applications.

• Korea Journal of Hospital Management
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• v.7 no.4
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• pp.1-23
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• 2002

This study examined the influence of the separation of prescribing and dispensing roles(SPD) policy implemented in Korea in July 2000, especially on the change in the net profit of medical institutions. Using the data set from the Korea's National Health Insurance and the previous research, this study elicited the following main results. First, tertiary care institutions was estimated to lose about 631 billion won after the SPD policy. Second, general hospitals and hospitals gained about 557 billion and 564 billion won, respectively. Third, it is shown that clinics also gained 389-659 billion won. Finally, however, the change in net profit of medical institutions after the SPD policy largely depends on different estimation models. Moreover, it also varies from the assumptions on the price differential of a reimbursable drug which worked as cross-subsidy to insufficient physician's fee before the SPD policy. Despite such limitations as lack of data outside of the National Health Insurance's coverage, this study differs from others. This is the first research to explore the effect of the SPD policy on different types of medical institutions and to attempt to purely focus on the SPD policy. In this study, we can draw the policy implication that preparing for a policy change, the government should set up the policy evaluation system to collect the concerned data and develop the methodologies in advance to the policy implementation.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.507-513
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• 2008

The purpose of this study is to analyze the factors affecting financial performance of community pharmacies after the implementation of the new drug policy in Korea: separation of drug prescription and dispensing (SPD). The online survey questionnaires were sent to the active pharmacists of the total 20,633 community pharmacies in Korea and 1,147 pharmacists responded to the survey (the response rate was 5.5%). The questionnaire asked simple financial data in order to compare their financial performances before and after the policy. With the SPSS package (version 12.0), two levels of data analysis were used: 1) descriptive statistics to see the financial status of the pharmacies; and 2) multiple regression analysis to find the factors. {or A multiple regression method was used for the data analysis.} The finding illustrated that the average net benefit of the pharmacies was 4,870 thousand won in August 2006, and the major factors affecting the net benefit were the location of pharmacy (geographical proximity to medical institutions), number of prescriptions, drug management services for patients, chain pharmacy membership. The findings of this study suggest that service improvement for patients, revitalization of non-prescription drug sales, professional management will contribute to promote community based pharmacy business.

• Korea Journal of Hospital Management
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• v.7 no.3
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• pp.84-101
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• 2002

This study estimated the influence of 'the separation of prescribing and dispensing roles' (SPD) policy, which implemented in July 2000, on the community pharmacies in Korea, by using data on the revenues and expenditures in the previous researches. We first assumed the rate of drug price differential was 20% with four different models which was based on various data of studies carried out in the similar period. Later, we applied different rates for the sensitivity analysis. According to the results, all community pharmacies made the net profit of 118.9 billion won (0.552 million won monthly per one pharmacy) after the SPD policy. The ratio of net profit to net sales dropped by 7.41%p from 22.19% to 14.78%. Additional sensitivity analysis indicated there were wide range of differences about whether net profit or net gain, and that extent which either existed.

• Journal of Communications and Networks
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• v.13 no.6
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• pp.583-590
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• 2011

Full-mesh IPSec tunnels pass through a black ("unsecure") network (B-NET) to any red ("secure") networks (RNETs). These are needed in military environments, because they enable dynamically changing R-NETs to be reached from a BNET. A dynamically reconfiguring security policy database (SPD) is very difficult to manage, since the R-NETs are mobile. This paper proposes advertisement process technologies in association with the tunnel gateway's protocol that sends 'hello' and 'prefix advertisement (ADV)' packets periodically to a multicast IP address to solve mobility and security issues. We focus on the tunnel gateway's security policy (SP) adaptation protocol that enables R-NETs to adapt to mobile environments and allows them to renew services rapidly soon after their redeployment. The prefix ADV process enables tunnel gateways to gather information associated with the dynamic changes of prefixes and the tunnel gateway's status (that is, 'down'/restart). Finally, we observe two different types of performance results. First, we explore the effects of different levels of R-NET movements on SP adaptation latency. Next, we derive the other SP adaptation latency. This can suffer from dynamic deployments of tunnel gateways, during which the protocol data traffic associated with the prefix ADV protocol data unit is expected to be severe, especially when a certain tunnel gateway restarts.