• Journal of the Ergonomics Society of Korea
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• v.30 no.6
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• pp.765-773
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• 2011

Objective: This study aims towards exploring a model of the HCI evaluation methods to improve the usability of mobile device, based on a case of a Mobile PDA system in a Museum context. Background: Mobile PDA systems in a Museum context is widely utilized for the educational purposes, but it is criticized for low usability that the device only play a role in textbooks on legs without any interactive educational activities. Therefore, the usability improvements on the mobile PDA system should be considered. Method 1: This model was developed with a combination of the expert review and the user testing, and with a combination of the qualitative and quantitative studies. In more details, first of all, a qualitative study was conducted as a combination of three different methods: 1) expert review with heuristics, 2) interviews with persons working in a museum, and 3) contextual enquiry. Results 1: The experts review provided with critical usability issues, and the semi-constructive interview helped to understand the background of the mobile device. Lastly, the contextual enquiry showed user experience problems and directions of improving the device from user's perspective. Method 2: Based on the results of the qualitative study, a questionnaire was designed. Results 2: The analysis of the quantitative study was conducted to generalize the problems, and prioritize the direction of improving the device within the limitation of the cost and time in a museum. Conclusion: This study has implications in developing an example of a HCI evaluation model to improve the user experience of the mobile device as well as finding problems and directions of how to improve the mobile PDA systems in the museum. Application: In fact, most of the studies related to the evaluation of the mobile device have been conducted in a laboratory context due to the cost and time. This paper, however, attempted to apply to various HCI research techniques from different constituents in real context.

• Smart Structures and Systems
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• v.17 no.6
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• pp.957-980
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• 2016

Structural damage detection (SDD) is a challenging task in the field of structural health monitoring (SHM). As an exploring attempt to the SDD problem, a hybrid self-adaptive Firefly-Nelder-Mead (SA-FNM) algorithm is proposed for the SDD problem in this study. First of all, the basic principle of firefly algorithm (FA) is introduced. The Nelder-Mead (NM) algorithm is incorporated into FA for improving the local searching ability. A new strategy for exchanging the information in the firefly group is introduced into the SA-FNM for reducing the computation cost. A random walk strategy for the best firefly and a self-adaptive control strategy of three key parameters, such as light absorption, randomization parameter and critical distance, are proposed for preferably balancing the exploitation and exploration ability of the SA-FNM. The computing performance of the SA-FNM is evaluated and compared with the basic FA by three benchmark functions. Secondly, the SDD problem is mathematically converted into a constrained optimization problem, which is then hopefully solved by the SA-FNM algorithm. A multi-step method is proposed for finding the minimum fitness with a big probability. In order to assess the accuracy and the feasibility of the proposed method, a two-storey rigid frame structure without considering the finite element model (FEM) error and a steel beam with considering the model error are taken examples for numerical simulations. Finally, a series of experimental studies on damage detection of a steel beam with four damage patterns are performed in laboratory. The illustrated results show that the proposed method can accurately identify the structural damage. Some valuable conclusions are made and related issues are discussed as well.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.3
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• pp.56-63
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• 2015

Several fields of science have demanded large-scale workflow support, which requires thousands of CPU cores or more. In order to support such large-scale scientific workflows, high capacity parallel systems such as supercomputers are widely used. In order to increase the utilization of these systems, most schedulers use backfilling policy: Small jobs are moved ahead to fill in holes in the schedule when large jobs do not delay. Since an estimate of the runtime is necessary for backfilling, most parallel systems use user's estimated runtime. However, it is found to be extremely inaccurate because users overestimate their jobs. Therefore, in this paper, we propose a novel system for the runtime prediction based on workload-aware clustering with the goal of improving prediction performance. The proposed method for runtime prediction of parallel applications consists of three main phases. First, a feature selection based on factor analysis is performed to identify important input features. Then, it performs a clustering analysis of history data based on self-organizing map which is followed by hierarchical clustering for finding the clustering boundaries from the weight vectors. Finally, prediction models are constructed using support vector regression with the clustered workload data. Multiple prediction models for each clustered data pattern can reduce the error rate compared with a single model for the whole data pattern. In the experiments, we use workload logs on parallel systems (i.e., iPSC, LANL-CM5, SDSC-Par95, SDSC-Par96, and CTC-SP2) to evaluate the effectiveness of our approach. Comparing with other techniques, experimental results show that the proposed method improves the accuracy up to 69.08%.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.503-514
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• 2015

This article tried to suggest ways to improve satisfaction of their life, as finding the determinants of the disabled through the cross-section research by the Ministry of Health and Welfare. This article used data from the 2011 investigation of actual condition for the Disabled, which is a representative of the disabled in Korea. For statistical analysis, this paper used PASW statistics 18.0 (SPSS Inc, Chicago, USA). Analysis of frequency, descriptive statistic and multiple regressions were conducted. The level of significance was set up as 0.05. As the result, we found that life satisfaction of the disabled was influenced by all factors such as factor in discrimination, socioeconomic factors, disability and health factor. Therefore, we think that the government needs to prepare a systemic method for extending right of the disabled and improving rehabilitation and independent living.

• Annals of Clinical Neurophysiology
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• v.5 no.2
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• pp.171-176
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• 2003

Backgrounds and Objectives: Despite of enormous clinical and laboratory researches focused on the useful markers in status epilepticus(SE), clinically applicable methods are not yet available. Although ketogenic diet (KD) is an old method of treating epilepsies, its outstanding antiepileptic effect in some epileptic patients needs re-evaluation of this methods. This study was performed to evaluate the effect of KD on the change of nitric oxide(NO) during the SE. Methods: After the determination of critical EEG stages in the pilocarpine-induced SE model, serum NO levels were measured with Griess reaction. Open cardiac puncture was done immediately after the four different EEG stages of SE in the KD rats and regular diet (RD) rats. Cessation of SE was done with the 10~20 mg/Kg of diazepam i.p. injection in each stages of SE in KD and RD rats. Results: Pilocarpine-induced SE showed reliable EEG and behavioral patterns in all rats. Also, KD did not affect the SE induced by pilocarpine in terms of the SE induction time and SE severity. Serum NO was consistently higher in KD rats than RD rats in all SE stages. Conclusions: KD significantly increases NO during the pilocarpine-induced SE. These finding might contribute the neuroprotective effect of KD in the SE.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1295-1296
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• 2007

A lot of researches about dye-sensitized solar cell (DSC) are recently being conducted. Because DSC has several advantages to pass the limits of silicon solar cells such as a low manufacturing expense, a simple manufacturing process and its transparency. But most researches on DSC are still conducted about the unit cell and laboratory-centered. That is, present researches on DSC are not practical. Therefore, researches about large area cells and modules have to be prerequisites for DSC to have the practicality. Characteristics of large area DSC are so different from those of small area DSC in aspect of fill factor and efficiency. In this study, we made an experiment on finding suitable size of DSC that has the most effective power according to the variation of active area. In detail, the experiment was conducted about the optimum ratio of length to width and we introduced the ratio of active area to non-active area to find the active area which has the best output. Because small DSC doesn‘t have the best output in comparison with total area of cell although the smaller DSC has the better efficiency. As a result, we achieved the optimum ratio of length to width of 8:3 and active area of $8cm^2$ as the optimum size for upscaling DSC.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1433-1435
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• 2003

Very decisive progress was made in advancing fundamental POL-IN-SAR theory and algorithm development during the past decade. This was accomplished with the aid of airborne & shuttle platforms supporting single -to-multi-band multi-modal POL-SAR and also some POL-IN-SAR sensor systems, which will be compared and assessed with the aim of establishing the hitherto not completed but required missions such as tomographic and holographic imaging. Because the operation of airborne test-beds is extremely expensive, aircraft platforms are not suited for routine monitoring missions which is better accomplished with the use drones or UAVs. Such unmanned aerial vehicles were developed for defense applications, however lacking the sophistic ation of implementing advanced forefront POL-IN-SAR technology. This shortcoming will be thoroughly scrutinized resulting in the finding that we do now need to develop most rapidly POL-IN-SAR drone-platform technology especially for environmental stress-change monitoring with a great variance of applications beginning with flood, bush/forest-fire to tectonic-stress (earth-quake to volcanic eruptions) for real-short-time hazard mitigation. However, for routine global monitoring purposes of the terrestrial covers neither airborne sensor implementation - aircraft and/or drones - are sufficient; and there -fore multi-modal and multi-band space-borne POL-IN-SAR space-shuttle and satellite sensor technology needs to be further advanced at a much more rapid phase. The existing ENVISAT with the forthcoming ALOSPALSAR, RADARSAT-2, and the TERRASAT will be compared, demonstrating that at this phase of development the fully polarimetric and polarimetric-interferometric modes of operation must be viewed and treated as preliminary algorithm verification support modes and at this phase of development are still not to be viewed as routine modes.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.257-262
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• 2013

Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis, the bone mineral density is reduced, bone microarchitecture deteriorates, and the amount and variety of proteins in bone are altered. $It^{\circ}{\emptyset}s$ caused by the imbalance between born resorption and born formation. Recently natural products from plants have been extensively studied as therapeutic drugs to treat and prevent various diseases. Wheat bran is the hard outer layers of wheat grain and produced as a by-product of milling in the production of refined grains. In oriental medicines, Bu So Maek (Tritici Immaturi Semen) with wheat bran has been used as bronchitis, sedatives and anti-sweating effects. However effects of wheat bran butanol fraction (WBB, 50 ${\mu}g/ml$) in osteoclast differentiation remains unknown yet. Thus we investigated the effects of WBB on RANKL induced osteoclast differentiation. WBB inhibited osteoclast differentiation by downregulating the RANKL-induced activations of MAP kinases. Moreover mRNA expression of osteoclast-mediating molecules such as c-Fos, NFATc1 and DC-STAMP were attenuated by WBB during osteoclast differentiation. The finding of this study show that WBB and its components might prevent osteoclast-related bone loss.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.663-666
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• 2009

Purpose: Primary malignant lymphomas of the salivary glands are uncommon. The parotid gland was most frequently involved, followed by the submandibular gland, minor salivary gland and sublingual gland. The most common subtype is mucosa - associated lymphoid tissue(MALT) lymphoma. We experienced a case of salivary MALT lymphoma involving parotid gland duct, so report a case with a review of the literature. Methods: A 65 year old female presented with a palpable mass on the left side of her cheek. There was no clinical or laboratory evidence of pre - existing autoimmune disease. Preoperative facial and neck CT with contrast showed $2.1{\times}1.7cm$ sized, ill defined, homogeneous low density mass near left masseter muscle, and no evidence of other enlarged lymph nodes. Results: At operation, a yellowish oval shaped mass was found slightly adhered to middle portion of the parotid gland duct, meaduring $2{\times}1.5{\times}0.7cm$. Microscopic finding showed that centrocyte - like cells, monocyte B cells and plasma cells were diffusely infiltrated. Immunophenotyping was preformed on fixed section. The majority of the small cells were immunoreactive for the B cell marker CD20. Based on the typical histological findings supported by immunostaining, the mass was defined as MALT lymphoma. Conclusion: We report that very rare case of MALT lymphoma involving parotid gland duct in 65 year old female patient was experienced with clinical characteristics, histologic features and references.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.437-440
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• 2007

A six-year-old, intact female Indian ring-necked parakeet (Psittacula krameri manillensis) was presented due to chronic weight loss and anorexia. The bird was tentatively diagnosed as proventricular dilation disease (PDD) by radiographic evidences of dilated crop and proventriculus. The patient was symptomatically treated, however the bird was die two months after the first presentation. At necropsy finding, distinctive signs of PDD were noted, and PDD concurrent with ingluvitis was finally diagnosed according to histopatholgic examination.