• Journal of applied mathematics & informatics
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• v.6 no.3
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• pp.915-920
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• 1999

We showed the upper p-estimate and p-power concavity are the necessary and sufficient condition of the space $M_{\Psi}$to be weak $L_pX>.

• Journal of the Ergonomics Society of Korea
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• v.23 no.4
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• pp.45-56
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• 2004

The purpose of this study is to evaluate perceived discomfort of working postures in terms of upper body (back, shoulder, and elbow) flexions when an external load varies. Eighteen subjects participated in an experiment of appraising perceived discomfort of varying upper body postures with three levels of external loads given. The ANOVA results showed that the perceived discomfort of upper body postures was significantly affected by the external load. It was also apparent that the interactions between external load and upper body posture were significant (p< 0.001). The result implies that a new posture classification scheme for workload assessment methods may be in need to reflect such interactions between external load and upper body posture. In order to support the statement, a regression model of perceived discomfort of upper body postures obtained from the experiment was developed and compared to that of perceived discomfort of seven work-related postures found in automobile assembly operations. The correlation coefficient between predicted and actual values of perceived discomfort was about 0.96. It is expected that the result help to properly estimate the body stress resluting from worker's postures and external loads and can be used as a valuable design guideline on preventing work-related musculoskeletal diseases in industry.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.10
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• pp.2731-2749
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• 2012

Sybil attack has been proved effective in mitigating the P2P botnet, but the impacts of some important parameters were not studied, and no model to estimate the effectiveness was proposed. In this paper, taking Kademlia-based botnets as the example, the model which has the upper and lower bound to estimate the mitigating performance of the Sybil attack is proposed. Through simulation, how three important factors affect the performance of the Sybil attack is analyzed, which is proved consistent with the model. The simulation results not only confirm that for P2P botnets in large scale, the Sybil attack is an effective countermeasure, but also imply that the model can give suggestions for the deployment of Sybil nodes to get the ideal performance in mitigating the P2P botnet.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.2
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• pp.99-104
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• 2002

In this paper, we construct a hybrid intelligent controller based on a fusion scheme of GA(Genetic Algorithm) and FCM(Fuzzy C-Means) clustering-based ANFIS(Adaptive Neuro-Fuzzy Inference System). In the structure identification, a set of fuzzy rules are generated for a given criterion by FCM clustering algorithm. In the parameter identification, premise parameters are optimally searched by adaptive GA. On the other hand, consequent parameters are estimated by RLSE(Recursive Least Square Estimate) to reduce the search space. Finally, we applied the proposed method to the truck backer-upper control and obtained a better performance than previous works.

• Physical Therapy Rehabilitation Science
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• v.5 no.3
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• pp.155-161
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• 2016

Objective: This study aimed to investigate the reliability and validity of a personal computer-based muscle viewer (PC-BMW) compared with that of a portable ultrasound (P-US) for measuring upper trapezius (UT) and transversus abdominis (TrA) muscle thickness at rest and during contraction. Design: Observational inter-rater reliability study. Methods: Fifty-five healthy participants (25 men, 30 women) participated in this study. PC-BMW and P-US were randomly measured at the UT and TrA muscles. Two examiners randomly obtained the images of all participants in 3 test sessions lasting 2 days. Intra-class correlation coefficients (ICCs), standard error of measurement, contraction ratio, and correlation were used to estimate reliability and validity. Pearson's correlation coefficients were used to analyze the relationship between muscle thickness measures taken from PC-BMW and P-US. Results: The intra-rater reliability ICCs of UT and TrA muscle thickness for the PC-BMW were >0.995, indicating excellent reliability. Inter-rater reliability ICCs for the PC-BMW ranged from 0.963 to 0.987. The P-US also exhibited high reliability. A high correlation was found between the measurements of the two muscles in PC-BMW and P-US (p<0.01). Conclusions: PC-BMW provides clear and excellent images, is pocket-sized and less expensive than a conventional ultrasound imaging system. PC-BMW can be utilized variously and has the advantage of rehabilitative ultrasound imaging. More research is needed to evaluate the utility of PC-BMW for rehabilitation.

• Nonlinear Functional Analysis and Applications
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• v.28 no.3
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• pp.647-657
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• 2023

The aim of this paper is to study certain subclass ${\tilde{S^q_{\Sigma}}}({\lambda},\,{\alpha},\,t,\,s,\,p,\,b)$ of analytic and bi-univalent functions which are defined by using symmetric q-derivative operator. We estimate the second and third coefficients of the Taylor-Maclaurin series expansions belonging to the subclass and upper bounds for Feketo-Szegö inequality. Furthermore, some relevant connections of certain special cases of the main results with those in several earlier works are also pointed out.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.20 no.4
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• pp.227-235
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• 2017

Purpose: Crohn's disease (CD) can involve any site of the gastrointestinal tract (GIT). However, the characteristics of upper GIT involvement in CD are unclear, especially in the Eastern pediatric population. This study aimed to estimate the prevalence of upper GIT involvement and identify the clinical features of Korean children with CD. Methods: This was a retrospective multicenter cohort study that included 52 pediatric patients with CD who underwent esophagogastroduodenoscopy and biopsy. The clinical symptoms and endoscopic and histologic features of the upper GIT were identified according to the presence or absence of upper gastrointestinal symptoms. Results: Among the 52 patients, upper GIT involvement was noted in 50.0% (26/52). The mean age at CD diagnosis was $14.1{\pm}2.1$ years. Gastric ulcer was the most common lesion (19.2%) found on upper GIT endoscopy, followed by duodenal ulcers (15.4%). Chronic inflammation was the most common histopathologic feature (75.0%), followed by gastric erosion (17.3%). Granuloma was found in 9.6% of patients. Helicobacter pylori infection was identified in 5.8% of patients. Endoscopic and histologic findings were not significantly different, but the mean values of erythrocyte sedimentation rate ($60.7{\pm}27.1$ vs. $43.0{\pm}27.6mm/h$, p=0.037) and C-reactive protein ($16.5{\pm}28.2$ vs. $6.62{\pm}13.4mg/dL$, p=0.014) were significantly different between patients with and without upper gastrointestinal CD symptoms. Conclusion: Upper GIT involvement was relatively common in pediatric patients with CD irrespective of upper gastrointestinal symptoms, and H. pylori infection was relatively uncommon. The results of this study should aid the establishment of regional guidelines for upper GIT examination.

• Korean Journal of Clinical Pharmacy
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• v.20 no.3
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• pp.242-247
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• 2010

Controlling inappropriate antibiotics prescribing for acute upper respiratory infections(URI) is a very important for prudent use of antibiotics and resistance control. Health Insurance Review and Assessment Service (HIRA) introduced Prescribing Evaluation Program and publicly reported antibiotics prescribing rate for URI of each health institution. We performed segmented regression analysis of interrupted time series to estimate the effect of public report on antibiotics prescribing rate using national health insurance claims data. The results indicate that just before the public report period, clinics' monthly antibiotics prescribing rate for URI was 66.7%. Right after the public report, the estimated antibiotics prescribing rate dropped abruptly by 12.3%p. There was no significant changes in month-to-month trend in the prescribing rate before and after the intervention.

• Bulletin of the Korean Mathematical Society
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• v.51 no.5
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• pp.1299-1324
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• 2014

We prove the existence of uniform attractors $\mathcal{A}_{\varepsilon}$ in the space $H^1(\mathbb{R}^N){\cap}L^p(\mathbb{R}^N)$ for the following non-autonomous nonclassical diffusion equations on $\mathbb{R}^N$, $$u_t-{\varepsilon}{\Delta}u_t-{\Delta}u+f(x,u)+{\lambda}u=g(x,t),\;{\varepsilon}{\in}(0,1]$$. The upper semicontinuity of the uniform attractors $\{\mathcal{A}_{\varepsilon}\}_{{\varepsilon}{\in}[0,1]}$ at ${\varepsilon}=0$ is also studied.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.10
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• pp.927-932
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• 2010

Estimation methods of motion intention from bio-signal present challenges in man machine interaction(MMI) to offer user's command to machine without control of any devices. Measurements of meaningful bio-signals that contain the motion intention and motion estimation methods from bio-signal are important issues for accurate and safe interaction. This paper proposes a novel motion estimation sensor based on a geometrical muscle changes, and a motion estimation method using the sensor. For estimation of the motion, we measure the circumference change of the muscle which is proportional to muscle activation level using a flexible piezoelectric cable (pMAS, piezo muscle activation sensor), designed in band type. The pMAS measures variations of the cable band that originate from circumference changes of muscle bundles. Moreover, we estimate the elbow motion by applying the sensor to upper limb with least square method. The proposed sensor and prediction method are simple to use so that they can be used to motion prediction device and methods in rehabilitation and sports fields.