• Journal of Power Electronics
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• v.18 no.5
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• pp.1555-1566
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• 2018

Proportional capacitor-current-feedback active damping (AD) is a common damping method for the resonance of LCL-type grid-connected inverters. Proportional capacitor-current-feedback AD behaves as a virtual resistor in parallel with the capacitor. However, the existence of delay in the actual control system causes impedance in the virtual resistor. Impedance is manifested as negative resistance when the resonance frequency exceeds one-sixth of the sampling frequency ($f_s/6$). As a result, the damping effect disappears. To extend the system damping region, this study proposes a virtual resistor-inductor-capacitor (RLC) AD method. The method is implemented by feeding the filter capacitor current passing through a band-pass filter, which functions as a virtual RLC in parallel with the filter capacitor to achieve positive resistance in a wide resonance frequency range. A combination of Nyquist theory and system close-loop pole-zero diagrams is used for damping parameter design to obtain optimal damping parameters. An experiment is performed with a 10 kW grid-connected inverter. The effectiveness of the proposed AD method and the system's robustness against grid impedance variation are demonstrated.

• The KIPS Transactions:PartC
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• v.11C no.3
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• pp.293-300
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• 2004

Ad hoc networks are groups of mobile hosts without any fixed infrastructure. Frequent changes in network topology owing to node mobility make these networks very difficult to manage. Therefore, enhancing the reliability of routing paths in ad hoc networks gets more important. In this paper, we propose a ZRP(Zone Routing Protocol)-based route discovery scheme that can not only reduce the total hops of routing path, but Improve security through authentications between two nodes. And to solve the problem in maintenance of routing paths owing to frequent changes of the network topology, we adopt a query control mechanism. The effectiveness of our scheme is shown by simulation methods.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.239-243
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• 2011

In wireless ad-hoc network, the detection of link breakage and re-establishing the route path causes lots of network overhead and results in communication delay. In the LBN method, the node causing a link breakage actively sends a message to neighbors so that they can instantly start re-establishing process of new path. In this paper we describe the result of network simulation we performed using NS2 to show the effectiveness of LBN method.

• Journal of Pharmacopuncture
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• v.23 no.3
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• pp.173-178
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• 2020

Objectives: Atopic dermatitis (AD) is a prevalent and chronic, pruritic inflammatory skin condition that can influence all age groups. AD is associated with a poor health-related quality of life. This randomized clinical trial was performed to compare the effectiveness of Olivederma (combination of aloe vera and virgin olive oil) or betamethasone regarding disease severity, quality of life, serum IgE and eosinophil count. Methods: Thirty-six AD patients were randomly allocated to topical Olivederma or betamethasone, and were followed for 6 weeks. Results: Total SCORAD severity scores showed significant decrease in both groups, while it was more prominent in Olivederma group (64.5% improvement in Olivederma vs. 13.5% improvement in Betamethasone, p-value < 0.001). Quality of life (DLQI questionnaire) of AD patients was significantly improved after 6 weeks treatment with Betamethasone (22.3%, p < 0.001) and Olivederma (60.7%, p-value < 0.001). Olivederma group showed a significantly lower DLQI score in comparison with Betamethasone treated patients after 6 weeks of therapy (p < 0.001). Improvements in eosinophil count and serum IgE was observed. Conclusion: In summary, this study shows that Olivederma is superior to topical Betamethasone after 6 weeks of therapy with regard to disease severity, quality of life and eosinophil count.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1189-1194
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• 2005

An Ad-hoc network which do not use wired and base station system is composed the group of mobile and wireless nodes. That is various type of restriction. The biggest restriction is depend on the confined energy of battery. The network is devide more than two, if one of nodes consumed all energy that node can no longer participate to network. In recent years, the many number of studies research not only energy saving but also the networks lifetime extension which is to solve this problem. In this paper, we examine a AODV routing protocol which is modified to improve networks lifetime in mobile ad-hoc network. The one of improvement for AODV protocol is maximize the networks lifetime as apply Energy Mean Value algorithm which considerate node energy. We show the effectiveness for modified AODV(New-AODV) compared with AODV using NS-2(Network Simulator 2) the various performance metrics.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.30 no.1
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• pp.87-105
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• 2017

Objectives : Atopic Dermatitis (AD) is chronic skin disease characterized by allergic hypersensitivity reactions. Saeng-ryo-Samul-tang (SRSM) can treat skin disease by cooling down blood heat, cealering away congenital fever and detoxicating. This study was conducted to investigate the effects of SRSM on AD induced by 2,4-dinitrochlorobenzene (DNCB) in mice Methods : In this study, the effects of SRSM on changes in body weights, thicknesses of dorsum skin, thicknesses and weights of ear, changes of symptoms on the dorsum skin, histopathological degree of ear and dorsum skin, IL-10 and $TNF-{\alpha}$ in serum were observed. And the effects on the proliferation rates of splenocytes were also investigated in vivo and in vitro study. Results : In SRSM topical application (Topical) group, SRSM oral application (Oral) group and SRSM Combination (Combi) group thickness of dorsum skin decreased significantly. But in TPC, ORL and CBN group, weight of ear didn't show any changes, but thickness of ear decreased significantly. And TPC, ORL and CBN group showed meaningful effectiveness symptoms like desquamation and erythema on AD's clinical espect. In histopathological observation, spongiosis, edema and inflammatory cell infiltration of epidermal were remarkably diminished in TPC, ORL and CBN group. And SRSM diminished the proliferation rates of splenocytes in vivo and vitro study. Conclusions : The present study suggests that SRSM can significantly reduced symptoms of AD, therefore SRSM is effective to treatment of AD.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.4
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• pp.303-312
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• 2024

Atopic dermatitis (AD) is the most common inflammatory pruritic skin disease worldwide, characterized by the infiltration of multiple pathogenic T lymphocytes and histological symptoms such as epidermal and dermal thickening. This study aims to investigate the effect of vinpocetine (Vinp; a phosphodiesterase 1 inhibitor) on a 1-chloro-2,4-dinitrobenzene (DNCB)-induced AD-like model. DNCB (1%) was administered on day 1 in the AD model. Subsequently, from day 14 onward, mice in each group (Vinp-treated groups: 1 mg/kg and 2 mg/kg and dexamethasone-treated group: 2 mg/kg) were administered 100 µl of a specific drug daily, whereas 0.2% DNCB was administered every other day for 30 min over 14 days. The Vinp-treated groups showed improved Eczema Area and Severity Index scores and trans-epidermal water loss, indicating the efficacy of Vinp in improving AD and enhancing skin barrier function. Histological analysis further confirmed the reduction in hyperplasia of the epidermis and the infiltration of inflammatory cells, including macrophages, eosinophils, and mast cells, with Vinp treatment. Moreover, Vinp reduced serum concentrations of IgE, interleukin (IL)-6, IL-13, and monocyte chemotactic protein-1. The mRNA levels of IL-1β, IL-6, Thymic stromal lymphopoietin, and transforming growth factor-beta (TGF-β) were reduced by Vinp treatment. Reduction of TGF-β protein by Vinp in skin tissue was also observed. Collectively, our results underscore the effectiveness of Vinp in mitigating DNCB-induced AD by modulating the expression of various biomarkers. Consequently, Vinp is a promising therapeutic candidate for treating AD.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.1
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• pp.29-34
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• 2013

This study presents the remote control of a mobile robot using iPhone based on ad hoc communication. Two control interfaces are proposed to control a mobile robot using iPhone : Remote control by a user and autonomous control. To evaluate the effectiveness of algorithms for trajectory following, a simulator are developed where a virtual robot follows a referenced trajectory in a monitor by iPhone interface. In the proposed simulator, some algorithms are tested how they work well or not for trajectory following of a mobile robot. Comparative results by remote user control and autonomous control are shown. Results of an experiment show that the proposed simulator can be effectively used for testing the effectiveness of autonomous tracking algorithms.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.383-390
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• 2013

Objectives: We evaluated the effects of an allergy control program on children with atopic dermatitis (AD) in five schools located within Gyeonggi-do. Methods: Based on the results of the 12-month prevalence of AD symptoms from an International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire of all students (n=2109; 1040 boys, 1069 girls) at five randomly selected schools, 227 students with AD symptoms were screened. Finally, 188 students with greater than 1 on SCORAD (SCORing Atopic Dermatitis) determined by a physician were selected. The allergy control program includes education related to allergic diseases, skin prick tests, and SCORAD evaluation, as well as keeping a daily journal to check the usage of moisturizer at least once a day. To determine the effectiveness of the allergy control program, SCORAD evaluation was performed again six weeks later. Results: The most common symptom for 12-month prevalence was rhinorrhea (33.9%), followed by atopic skin lesions (14.8%) and wheezing (4.0%). The 12-month prevalences of the three allergic diseases were higher for boys than for girls, and a significant difference was found for allergic rhinitis (P<0.001). The mean SCORAD index decreased significantly from 26.1 to 17.5 after the completion of the six-week control program (P<0.01). In particular, these differences were more pronounced for the group which used the daily journal (P<0.001). Conclusions: Our findings indicate that the allergy control program including usage of a daily journal as well as regular monitoring could be a promising tool for preventing and alleviating the symptoms of allergic diseases.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.341-349
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• 2009

This study compares the relative effectiveness of affective factor(Ad attitude) and cognitive factor(Brand cognition) on brand attitude among three ad types - direct comparative, indirect comparative, and noncomparative ads. The results showed that in direct comparative advertising context the brand cognition is dominant in determining brand attitude. In indirect comparative advertising context brand cognition is also dominant in determining brand attitude, but the difference is less than direct comparative advertising. In noncomparative advertising context the ads attitude is dominant in determining brand attitude. According to research outcomes, it could be said that direct comparative advertising is more effective than indirect comparative advertising.