• Journal of International Academy of Physical Therapy Research
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• v.2 no.2
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• pp.274-280
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• 2011

This study was designed to analyze repetitive dorsiflexion and plantarflexion exercises in ankles have effects on the muscle tones of triceps, vastus medialis and gastrocnemius. 25 healthy woman volunteers(ankle dorsiflexion exercise group: 13, ankle plantarflexion exercise group: 12) participated in the two ankle exercise models, which have performed 3 times a week for 3 weeks. Myotonometer was used to measure the muscle tones of the triceps, vastus medialis, gastrocnemius muscles, and measurements were performed before and after the application of the each exercise model. Repeated measured paired t-test and independent t-test was used to determine a statistical significance. The group of repetitive dorsiflexion exercise of the ankle have effects on the muscle tones of triceps, vastus medialis and gastrocnemius (p>.05). The group of repetitive plantarflexion exercise of the ankle have effects on the muscle tones of triceps, vastus medialis and gastrocnemius(p>.05). The groups of repetitive dorsiflexion and plantarflexion exercise of the ankle have effects on the muscle tones of triceps, vastus medialis and gastrocnemius(p>.05).

• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.293-299
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• 2005

Automatic reclosing is a typical protection method in power distribution systems for the clearing of temporary faults. However, it has a fatal weakness in regards to voltage sags because it produces repetitive voltage sags. In this paper, we explored the repetitive impact of voltage sag due to the automatic reclosing of power distribution systems. The actual tests of low voltage loads were carried out for obtaining the susceptibility of voltage sags. The final results of the tests yielded power acceptability curves of voltage sag, and the curves transformed the 3-dimensional CBEMA (Computer Business Equipment Manufacturer Association) format. For the quantitative evaluation of the impact of repetitive voltage sags, an assessment formulation using the voltage sag contour was proposed. The proposed formulation was tested by using the voltage sag contour data of IEEE standard and the results of the test. Through the case studies, we verified that the proposed method can be effectively used to evaluate the actual impact of repetitive voltage sags.

• Journal of the Ergonomics Society of Korea
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• v.33 no.6
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• pp.565-575
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• 2014

Objective: The aim of this study is to evaluate the effect of weight of load and time on the physical workload of repetitive upper-limb tasks with handling light weight loads using EMG and perceived discomfort, and to investigate the relationship between EMG and perceived discomfort for those repetitive tasks of moving light weight loads. Background: Repetitive upper-limb motion is known as one of the main risk factors of musculoskeletal disorders, and a lot of repetitive tasks are carried out while handling light weight loads in the industry. In evaluating the workload of repetitive tasks handling light weight loads, EMG and perceived discomfort can be used, though their relationship in those work conditions are not much investigated. Method: A laboratory experiment with 18 healthy males were conducted to record EMG signals from 5 muscle sites of the right arm and shoulder and rate perceived discomforts for the body parts and the whole body while carrying out repetitive materials-handling tasks for 52min. The subjects were divided into 3 groups which handled the loads of 1kg, 2kg and 3kg, respectively. ANOVAs were conducted to analyze the effects of the weight and time on RMS of EMG amplitude (normalized RMS: NRMS), median frequency of power spectrum of EMG (normalized MDF: NMDF) and perceived discomfort. The correlations between NRMS and NMDF and perceived discomfort were also analyzed. Results: Statistically significant muscular fatigue effects were not found from NRMS and NMDF in most muscles, while there were significant increases of discomfort as the task time elapsed. It was shown that there were an increasing trend of the muscular activity as the weight of load increased and a decreasing trend of median frequency of EMG of upper and lower arms as time elapsed. It was found that there were significant negative correlations between NMDFs from the lower arm and discomfort ratings, though the relationships were weak. Conclusion: It can be concluded that the working conditions adopted in this study were not enough to induce muscular fatigue, while there was significant increase in perceived discomfort. A further study is necessary to integrate the objective and subjective measures for more reliable and sensitive evaluation of workload of repetitive tasks of handling light weight loads. Application: This study can be used as a basic study for the evaluation of workload of repetitive tasks handling light weight loads.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.135-142
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• 2005

This paper presents an adaptive repetitive control scheme for optical disk drives to track a variable periodic reference signal. Periodic disturbances can be adequately attenuated using the concept of repetitive control, provided the period is known. Because optical disk drives support various speeds, they have the varying periodic disturbances. Based on repetitive control to change sampling frequency to follow the change of reference period, an adaptive repetitive control is proposed in order to deal with such disturbances. The proposed control consists of the repetitive controller and the frequency generator. The former uses a varying sampler operating at fixed multiple times of the disturbance frequency and the latter generates the changeable sampling frequency based on the disturbance frequency. The experimental results on the control of an optical disk drive demonstrate the effectiveness of the proposed schemes and the improvement of random access time as well.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.206-212
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• 2000

Since some cyanobacterial isolates under selective culturing conditions are lacking of characteristic specialized cells or showing altered morphology, the morpho-taxonomic criteria are not accurate enough to discriminate between species. Instead of morphological parameters, a method based on the single or the combination of repetitive oligonucleotides in a single PCR, repetitive oligonucleotides-primed PCR (ROP-PCR), was applied to generate DNA profiles for members of the cyanobacterial genera Anabaena and Oscillatoria, both of which are responsible for causing poisonous blooms in various freshwater systems. ROP-PCR performed on 10 isolates of the cyanobacteria with ERIC and REP sequences from gram-negative bacteria, STRR1A and LTRR sequences derived from cyanobacterial genome, and eukaryotic repetitive sequences, led to the identification of distinct genotypes, and provided specific and repeatable DNA fingerprints for cyanobacterial isolates. Grouping analysis of cyanobacterial isolates showed a signifiant difference depending on the primer used in PCR.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.99-105
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• 2011

This paper presents a method to design a centralized repetitive controller that is robust to variations in the multiple system parameters. The uncertain parameters are specified probabilistically by their probability distribution functions. Instead of working with the distribution functions directly, the centralized repetitive controller is designed from a set of models that are generated from the specified probability functions. With this multiple-model design approach, any number of uncertain parameters that follow any type of distribution functions can be treated. Furthermore, the controller is derived by minimizing a frequency-domain based cost function that produces monotonic convergence of the tracking error as a function of repetition number. Numerical illustrations show how the proposed multiple-model design method produces a repetitive controller that is significantly more robust than an optimal repetitive controller designed from a single nominal model of the multiple system.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.168-177
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• 2019

Dysregulation of excitatory neurotransmission has been implicated in the pathogenesis of neuropsychiatric disorders. Pharmacological inhibition of N-methyl-D-aspartate (NMDA) receptors is widely used to model neurobehavioral pathologies and underlying mechanisms. There is ample evidence that overstimulation of NMDA-dependent neurotransmission may induce neurobehavioral abnormalities, such as repetitive behaviors and hypersensitization to nociception and cognitive disruption, pharmacological modeling using NMDA has been limited due to the induction of neurotoxicity and blood brain barrier breakdown, especially in young animals. In this study, we examined the effects of intraperitoneal NMDA-administration on nociceptive and repetitive behaviors in ICR mice. Intraperitoneal injection of NMDA induced repetitive grooming and tail biting/licking behaviors in a dose- and age-dependent manner. Nociceptive and repetitive behaviors were more prominent in juvenile mice than adult mice. We did not observe extensive blood brain barrier breakdown or neuronal cell death after peritoneal injection of NMDA, indicating limited neurotoxic effects despite a significant increase in NMDA concentration in the cerebrospinal fluid. These findings suggest that the observed behavioral changes were not mediated by general NMDA toxicity. In the hot plate test, we found that the latency of paw licking and jumping decreased in the NMDA-exposed mice especially in the 75 mg/kg group, suggesting increased nociceptive sensitivity in NMDA-treated animals. Repetitive behaviors and increased pain sensitivity are often comorbid in psychiatric disorders (e.g., autism spectrum disorder). Therefore, the behavioral characteristics of intraperitoneal NMDA-administered mice described herein may be valuable for studying the mechanisms underlying relevant disorders and screening candidate therapeutic molecules.

• Journal of Korean Neurosurgical Society
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• v.50 no.2
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• pp.134-138
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• 2011

The authors report a case of epidural and extraforaminal calcification caused by repetitive triamcinolone acetonide injections. A 66-year-old woman was admitted presenting with lower extremity weakness and radiating pain in her left leg. Ten months before admission, the patient was diagnosed as having an L4-5 spinal stenosis and underwent anterior lumbar interbody fusion followed by posterior fixation. Her symptoms had been sustained and she did not respond to transforaminal steroid injections. Repetitive injections (10 times) had been performed on the L4-5 level for six months. She had been taking bisphosphonate as an antiresorptive agent for ten months after surgery. Calcification in the ventral epidural and extraforaminal space was detected. The gritty particles were removed during decompressive surgery and these were proven to be a dystrophic calcification. The patient recovered from weakness and radiating leg pain. Repetitive triamcinolone acetonide injections after discectomy may be the cause of dystrophic calcification not only in the degenerated residual disc, but also in the posterior longitudinal ligament. Possible mechanisms may include the toxicity of preservatives and the insolubility of triamcinolone acetonide. We should consider that repetitive triamcinolone injections in the postdisectomy state may cause intraspinal ossification and calcification.

• KSBB Journal
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• v.25 no.2
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• pp.199-204
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• 2010

We generated the feasibility of DNA separation in free-solution using genetically engineered repetitive polypeptides as drag-tags. Two different-sized repetitive polypeptides were designed, expressed in E. coli, and purified. They were conjugated to a fluorescently labeled DNA (100 base), and the electrophoretic mobilities of these conjugate molecules were analyzed on a microchip. The results of these studies indicate that genetically engineered repetitive polypeptide is a prominent candidate for rapid and high-throughput genetic mutation detection, such as SNP analysis.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.71-76
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• 2002

In order to achieve repetitive somatic embryogenesis in cacao (Theobroma cacao L.), callus derived from floral tissues were continuously cultured in a medium containing 2,4-D. In 5% of the explants, repetitive somatic embryogenesis was observed after 8 weeks and maintained in a globular stage for several weeks. This is the first report showing repetitive somatic embryogenesis in cacao. The calli were bombarded with a plasmid containing $\beta$-glucuronidase (gus) as reporter gene. Two week old calli showed the high average number of cells expressing the us gene. The effect of osmotic agents (mannitol, sorbitol and sucrose) on gene expression was evaluated. Pre-treatment during 16 h with 0.25 M mannitol revealed an improvement in gene expression. The potential utilization of the repetitive embryogenesis, combined with osmotic treatment, is discussed as an alternative to achieve stable transgenic cacao plants.