• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.26 no.2
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• pp.163-173
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• 2024

Objective: We aimed to investigate the incidence of flow arrest during carotid artery stenting (CAS) with filter-type embolic protection device (EPD), identify any predisposing factors for those situations, and contemplate intraprocedural precautionary steps. Methods: CAS was performed in 128 patients with 132 arteries using filter-type EPD. The characteristics of treated patients and arteries were compared between groups with and without flow arrest. Results: The incidence of flow arrest during CAS with filter-type EPD was 17.4%. In flow arrest group, cases of vulnerable plaques (p=0.02) and symptomatic lesions (p=0.01) were significantly more common, and there were more cases of debris captured by EPD in a planar pattern (p<0.01). Vulnerable plaques were significantly more common in the procedures showing a planar pattern than in the cases with other patterns (p<0.01). Flow arrest group showed a significantly higher rate of ischemic complications (p<0.05), although there were no significant periprocedural neurological changes. The planar pattern of captured debris in filter-type EPD was the only significant risk factor for flow arrest (adjusted odds ratio 88.44, 95% confidence interval 15.21-514.45, p<0.05). Conclusions: Flow arrest during CAS with filter-type EPD is not uncommon and associated with increased ischemic complications. Symptomatic stenoses and vulnerable plaque are related to this event. The planar pattern of captured debris on the EPD was the only significant risk factor for the flow arrest. Clinicians must pay attention to the occurrence of flow arrest and react quickly when performing CAS.

• Journal of KIISE:Information Networking
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• v.37 no.5
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• pp.317-326
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• 2010

Nowadays, transmission bandwidth for network traffic is increasing and the type is varied such as peer-to-peer (PZP), real-time video, and so on, because distributed computing environment is spread and various network-based applications are developed. However, as PZP traffic occupies much volume among Internet backbone traffics, transmission bandwidth and quality of service(QoS) of other network applications such as web, ftp, and real-time video cannot be guaranteed. In previous research, the port-based technique which checks well-known port number and the Deep Packet Inspection(DPI) technique which checks the payload of packets were suggested for solving the problem of the P2P traffics, however there were difficulties to apply those methods to detection of P2P traffics because P2P applications are not used well-known port number and payload of packets may be encrypted. A proposed algorithm for identifying P2P heavy traffics based on flow transport parameters and behavioral characteristics can solve the problem of the port-based technique and the DPI technique. The focus of this paper is to identify P2P heavy traffic flows rather than all P2P traffics. P2P traffics are consist of two steps i)searching the opposite peer which have some contents ii) downloading the contents from one or more peers. We define P2P flow patterns on these P2P applications' features and then implement the system to classify P2P heavy traffics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1549-1554
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• 2015

This study examined experimentally the characteristics of the flow pattern and particle suspension in an agitated vessel with a bottom baffle. A flow pattern of the particles was shown to increase the upward flow from the center of the agitated vessel bottom. The suspended particles from the experiment found that the particle suspension was promoted by the development of an Ekman boundary layer. The optimal conditions of the impeller, and the agitated vessel bottom baffle within the experimental range were as follows: Impeller, $n_p=6$, d/D=0.5, and b/d=0.3; and bottom baffle, $n_b=6$, $d_b/D=0.5$ and $b_w/D=0.05$.

• PNF and Movement
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• v.18 no.2
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• pp.297-303
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• 2020

Purpose: The purpose of this study was to examine the effects of inhalation and exhalation exercise combined with upper extremity proprioceptive neuromuscular facilitation pattern on two spirometry values: forced volume vital (FVC) and peak expiratory flow (PEF). Methods: Thirty-two healthy adults were divided into two groups: 1) a combined group, which performed upper extremity D2 flexion pattern (shoulder flexed/abducted/external rotated, forearm supinated, wrist radial deviated, and finger extended) during exhalation and D2 extension pattern (shoulder extended/adducted/internal rotated, forearm pronated, wrist ulnar deviated, and finger flexed) during inhalation; and 2) reverse combined group, which performed the D2 flexion pattern during inhalation and the D2 extension pattern during exhalation. The inverse application of upper extremity movements during inhalation and exhalation induced selective resistance or assistance on respiration. FVC and PEF were measured at two time points, before and after four weeks. Results: In both groups, the pre-post intervention comparison showed significant increases in FVC and PEF (p < .05). In the between-groups comparison, the reverse combined group showed a significantly higher PEF than the combined group at four weeks post intervention (p < 0.05). Conclusion: The combined respiration exercise with reverse PNF upper extremity patterns using selective resistance showed an effective increase in PEF in healthy adults. Clinicians and researchers might consider using selective resistance as a widely applicable and cost-effective option for respiratory rehabilitation planning.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.4
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• pp.398-410
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• 1998

Two-phase flow phenomena are observed in many industrial facilities and make much importance of optimum design for nuclear power plant and the liquid transportation system. The particular flow pattern depends on the conditions of pressure, flow velocity, and channel geometry. However, the research on drag reduction in two-phase flow is not intensively investigated. Therefore, experimental investigations have been carried out to analyze the drag reduction and void fraction by polymer addition in the two-phase flow system. We find that the polymer solution changes the characteristic of two-phase flow. The peak position of local void friction moves from tile wall of the pipe to the center of the pipe when polymer concentration increase. And then we predict that it is closely related with the frau reduction.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.2
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• pp.55-63
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• 2024

Purpose : The purpose of this study is to determine the effects of scapula and pelvis symmetrical reciprocal pattern exercise of PNF concept on respiratory function and quality of life in elderly subjects. Methods : Nineteen elderly subjects with healthy were recruited. Subjects performed scapula and pelvis symmetrical reciprocal pattern exercise of PNF concept. Exercise was appied 30 minutes three times per week for four weeks. The respiratory function and quality of life (QOL) test three times (before, two weeks, and four weeks). Respiratory function includes forced vital capacity (FVC), forced expiratory volume at one second (FEV₁), Peak Expiratory Flow (PEF) and chest cage expansion test (CCET). The QOL test was measured Korean WHOQOL-BRIEF. The analysis method was analyzed through the one-way ANOVA repeated methods, and the statistical significance is α=.05. It was analyzed through the post test Bonferroni test. Results : After the 4 week scapula and pelvis symmetrical reciprocal pattern exercise of PNF concept showed statistically significant differences in the respiratory function (FVC, FEV₁, PEF, and CCET), and QOL (p<.05). As a result of the post-hoc test, FVC showed a significant increase in the mid test and post test compared to the pre test (p<.05), FEV₁ showed a significant increase in the post test compared to the pre test (p<.05). PEF showed a significant increase in all pre-test, mid-test, and post-test sections (p<.05), CCET showed a significant increase in all pre-test, mid-test, and post-test sections (p<.05). QOL showed a significant increase in all pre-test, mid-test, and post-test sections (p<.05). Conclusion : In this study, the scapula and pelvis symmetrical reciprocal pattern exercise of PNF concept improved respiratory function and QOL. The findings suggest that this intervention could be beneficial in improving respiratory function and QOL in the elderly.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.451-459
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• 2020

This study aims to examine the relationship of the four factors that increase the protection of minority shareholder investment. The factors are non-controlling shareholders, corporate governance, free cash flow, and shareholder wealth. The data for this study is obtained from the 2017 annual reports of 136 Thai public companies listed in the Market of Alternative Investment of Thailand (MAI). The analysis uses a multiple regression model to determine which factors encourage and which inhibit the protection of minority shareholder investment. The study tests four hypotheses. The results rejected H1 because non-controlling shareholders have negatively correlated with minority shareholder investment protection (beta -0.155 and p-value 0.050). The results accepted H2, H3 and H4 as follows. H2: corporate governance has positively correlated with minority shareholder investment protection (beta 0.17 and p-value 0.031). H3: free cash flow has positively correlated with minority shareholder investment protection (beta 0.214 and p-value 0.007). H4: shareholder wealth has positively correlated with minority shareholder investment protection (beta 0.318 and p-value 0.000). The major findings suggest strong minority shareholder investment protection was enhanced by increasing corporate governance, free cash flow and shareholder wealth. The protection of minority shareholder investment needs to reduce non-controlling shareholding pattern.

• Journal of the Korea Society of Computer and Information
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• v.19 no.3
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• pp.45-54
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• 2014

In this paper, an improved two-step P2P traffic classification scheme is proposed to overcome the limitations of the existing methods. The first step is a signature-based classifier at the packet-level. The second step consists of pattern heuristic rules and a statistics-based classifier at the flow-level. With pattern heuristic rules, the accuracy can be improved and the amount of traffic to be classified by statistics-based classifier can be reduced. Based on the analysis of different decision tree algorithms, the statistics-based classifier is implemented with REPTree. In addition, the ensemble algorithm is used to improve the performance of statistics-based classifier Through the verification with the real datasets, it is shown that our hybrid scheme provides higher accuracy and lower overhead compared to other existing schemes.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.4
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• pp.342-349
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• 1988

The characteristics of flow pattern transitions in a horizontal cocurrent gas-liquid flow have been investigated by means of a statistical analysis of instantaneous pressure drop curves at an orifice. The dimensionless intensity of pressure drop fluctuation shows a sudden change during the course of flow transitions, indicating that it may be a good measure to identify the flow regime transitions. The probability density function of the curves feature a unique pattern depending upon the flow regimes and the statistical properties of the PDF also have particular ranges for each flow regime. In conclusion, the statistical analysis of instantaneous pressure drops may be a powerful tool for predicting the flow regime transitions.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.255-261
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• 2002

The purpose of this study was to compare the microleakage pattern of flowable composite resin to sealant, composite resin used in preventive resin restoration and glass ionomer cement used as liner. 120 extracted sound human molars were divided into 6 groups : group 1 and 2:sealant ; group 3 and 4:preventive resin restoration ; group 5 and 6:sandwich technique restoration. For the experimental groups(group 2, 4 and 6), flowable composite resin(Tetric flow) was used. For the control group, Concise was used as sealant material(group 1), Z-100 with Concise were used as preventive resin restoration(group 3), and Vitrebond was used as cavity liner(group 5). All the restorations were thermocycled and the degree of dye penetration was evaluated with stereomicroscope. The microleakage of each group was measured and statistically analyzed. The results of the present study were as follows : 1. In group 1 and 2, there was no statistically significant difference in microleakage between Concise and Tetric flow(p>0.05). 2. In groups of preventive resin restorations, there was no statistically significant difference in microleakage between Z-100 with Concise and Tetric flow(p>0.05). 3. The microleakage of Vitrebond and Tetric flow used as liner showed no statistically significant difference(p>0.05).