• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.12
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• pp.4385-4399
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• 2021

The Internet of Things (IoT) eHealth systems composed by Wireless Body Area Network (WBAN) has emerged recently. Sensor nodes are placed around or in the human body to collect physiological data. WBAN has many different applications, for instance health monitoring. Since the limitation of the size of the battery, besides speed, reliability, and accuracy; design of WBAN protocols should consider the energy efficiency and time delay. To solve these problems, this paper adopt the end-edge-cloud orchestrated network architecture and propose a transmission based on reinforcement algorithm. The priority of sensing data is classified according to certain application. System utility function is modeled according to the channel factors, the energy utility, and successful transmission conditions. The optimization problem is mapped to Q-learning model. Following this online power control protocol, the energy level of both the senor to coordinator, and coordinator to edge server can be modified according to the current channel condition. The network performance is evaluated by simulation. The results show that the proposed power control protocol has higher system energy efficiency, delivery ratio, and throughput.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.4
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• pp.506-515
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• 1999

Dental practice can produce and spread some infectious diseases from patients to dentist, dental assistant, and dental labors. One possible method for preventing these cross-contamination is to immerse dental impression in chemical disinfectants. So for many investigators studied on the dimensional changes of dental impressions and on the surface qualities of stone casts made from impression following immersion in disinfectants. This study was proposed to evaluate some popular impression disinfectant combination from the point of dimensional stability. Impression was taken from dental arch-shaped metal model. Irreversible hydrocolloid and 3 elastomers(polyvinyl siloxane, polysulfide, polyether) were immersed in 3 disinfectants (2% glutaraldehyde, 1% povidone-iodine, 0.5% sodium hypochlorite) for 10 minutes and measured both cross-arch and anterior-posterior distance under stereo microscope to evaluate dimensional change. The results obtained were as follows: 1. Dimensional changes of irreversible hydrocolloid impression was statistically different in cross-arch and anterior-posterior distance when immersed in 2% glutaraldehyde solution and in anterior-posterior distance when immersed in 0.5% sodium hypochlorite solution from control group (p<0.05). 2. Dimensional changes of polyvinyl siloxane and polysulfide impression were not statistically different from control group (p>0.05). 3. Dimensional changes of polyether impression was statistically different in cross-arch distance when immersed in 0.5% sodium hypochlorite solution and in anterior-posterior distance when immersed in 1% povidone-iodine solution from control group (p<0.05). 4. In all cases, dimensional changes were less than 0.1% from the original dimension and concluded clinically acceptable.

• Journal of Digital Convergence
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• v.16 no.11
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• pp.383-392
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• 2018

This study investigates convergent factors to TOEIC learning flow among some health college students in TOEIC class. The questionnaire was performed on 255 health college students in TOEIC class from college located in J area from May 1st, 2018 to May. 25th, 2018 by using an unregistered self-administered questionnaire. The hierarchical multiple regression analysis shows the following results. The TOEIC learning flow of respondents turned out to be significantly higher in following groups: a group in which self efficacy is higher, a group in which academic control is higher, a group in which school resilience is higher. The results show explanatory power of 43.4%. As the results of the study, it is necessary to make an effort to increase self efficacy, academic control and school resilience to improve the TOEIC learning flow among health college students. These results can be used in development and operation of TOEIC learning program to higher TOEIC learning flow in health college students. Further studies need the analysis of structural equation model effecting TOEIC learning flow of health college students.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.554-561
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• 2022

Technology development related to maritime autonomous surface ships (MASS) is actively progressing around the world. However, since there are still many technically unresolved problems such as communication, cybersecurity, and emergency response capabilities, it is expected that it will take a lot of time for MASS to be commercialized. In this study, we proposed a ship group navigation system in which one leader ship and several follower ship are grouped into one group. In this system, when the leader ship begins to navigate, the follower ship autonomously follows the path of the leader ship. For path following, PD (proportional-derivative) control is applied. In addition, each ship navigates in a straight line shape while maintaining a safe distance to prevent collisions. Speed control was implemented to maintain a safe distance between ships. Simulations were performed to verify the ship group navigation system. The ship used in the simulation is the L-7 model of KVLCC2, which has related data disclosed. And the MMG (Maneuvering Modeling Group) standard method proposed by the Japan Society of Naval Architects and Ocean Engineering (JASNAOE) was used as a model of ship maneuvering motion. As a result of the simulation, the leader ship navigated along a predetermined route, and the follower ship navigated along the leader ship's path. During the simulation, it was found that the three ships maintained a straight line shape and a safe distance between them. The ship group navigation system is expected to be used as a navigation system to solve the problems of MASS.

• Korean Journal of Community Nutrition
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• v.1 no.2
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• pp.260-268
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• 1996

This study aimed to develop an experimental animal model of duodenal ulcer for application to nutrition, and to verify the nutritional characteristics. The 7 different doses and 8 different injections of cysteamine and 2 kinds of diets with different casein levels(10%, 20%) were tested to examine the incidence and the process of duodenal ulcer in female Sprague-Dawley rats. The result showed that the duodenal ulcer was induced when rats fed 10% casein diet(for 9 days) were injected 6 times with 13mg/100g BW cysteamine. The first injection was conducted after 24 hours of fasting, followed by the 2nd shot after 3 hours. The following shots were repeated every 3 day(4th and 7th days). Duodenal ulcer was observed 3 days after the last injection by optical microscope and the naked eye. The characteristics of nitrogen bioavailability of duodenal ulcer model were as followings : 1) gastric emptying rate was faster, 2) trypsin activity at duodenum was higher, 3) total protein concentration at serum and nitrogen retention rate were lower than the control. (Korean J Community Nutrition 1(2) : 260-268, 1996)

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.37
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• pp.361-389
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• 2008

The purpose of this study is to detect the factors which have an effect on transformation level and performance and to provide the ways of successful transformation and vitalization from OEM to ODM. This study was proceeded by an empirical analysis. A model and hypotheses were set up and they were verified through the empirical analysis. Those factors were divided into four, inner company factors, strategic factors, core competence factors and purchase determining factors. In the result of the model suitability analysis on the study model of relationship among 'influencing factors of ODM transformation - ODM transformation level-export performance', every factors, $X^2=912.067$, DF=261, p value=0.000, GFI=0.737, AGFI=0.620, NFI=0.786, IFI=0.837, CFI=0.834, Q value=3.495 were rather insufficient to be a good model, but they were good enough for the general analysis. Taking these accounts into consideration, this study suggests the following implications. First, making a plan and setting up strategies in advance are required. Second, financial plan has to be prepared. Third, trends in global markets have to be analyzed. Fourth, companies have to focus on developing new materials and products through R&D. Fifth, quality competitiveness and quality control systems are required.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.71-80
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• 1996

A number of experimental evidences suggest that the rnun ventrolateral medulla(RVLM) is the final common pathway in the regulation of arterial blood pressure. A Voup of neurons in the RVLM, called the cardiovascular neurons (UN), show spontaneous activity temporally synchronized with the periodic cardiac cycle. These neurons affect the sympathetic nerve discharge(SND), thus are believed to be responsible for blood pressure control. The present experiment identified 98 UVNs in 42 cats based on the temporal relationships between each neuron's activity with both the cardiac cycle and SWD. In 20 UWL changes of spontaneous firing rate(FR) during the somatosympathetic reflex(SSR) were studied Five different firing patterns were observed during the pressor and depressor responses of SSR, implying that they form an interconnected neuronal circuit interacting with one another to generate efferent signals for blood pressure regulation. In the following companion paper, the firing patterns of CVN are analyzed to develop a minimal neuronal circuit model explaining the present experimental outcome.

• The Transactions of the Korea Information Processing Society
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• v.6 no.9
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• pp.2281-2293
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• 1999

Many applications such as nuclear power plant monitoring, plant process control, stock market management, and network data management require a database system supporting both temporal data model and active rule processing. There have been some efforts to extend the temporal functionalities of the active database system, but an active database system based on temporal database, especially the one applied to the real application is rare. In this paper, we proposed an active temporal rule model based on bi-temporal database. And a rule language following the proposed rule model was described with its execution semantics. Then, how to apply to the nuclear power plant monitoring system was given as the examples.

• The Korea Journal of Herbology
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• v.28 no.2
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• pp.1-7
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• 2013

Objectives : Sesamin, a major lignan in sesame seeds, has been reported to have neuroprotective effects against in vitro ischemia and in vivo MCAo-reperfusion cerebral ischemia model, however, there is no reports in an in vivo global cerebral ischemia model. The purpose of the study was to investigate the neuroprotective effect of sesamin in global cerebral ischemia induced by four-vessel occlusion (4-VO) in rats through inhibition of microglial activation in this model. Methods : The neuroprotective effects were investigated using a 10 min of 4-VO ischemia rat model by measuring intact pyramidal neurons in the CA1 region of the hippocampus using Nissle staining. The antiinflammatory or reducing neurotoxicity effect was investigated using immunohistochemisty, RT-PCR and western blot analysis of inflammatory or neurotoxic mediators. Results : Intraperitoneal injection of sesamin at doses of 0.3, 1.0, 3.0, and 10.0 mg/kg at 0 min and 90 min after ischemia conferred 26.6%, 30.1%, 42.5%, and 30.5% neuroprotection, respectively, compared to the vehicle-treated control group. A 3.0 mg/kg dose of sesamin inhibited microglia activation and consequently, cyclooxygenase-2, inducible nitric oxide, and interleukine-$1{\beta}$ expressions at 48 h after reperfusion. Conclusions : Sesamin protects neuronal cell death through inhibition of microglial activation or the production of neurotoxic metabolites and proinflammatory mediators by microglia such as COX-2, iNOS and IL-$1{\beta}$ in global cerebral ischemia.

• The Korean Journal of Pain
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• v.33 no.4
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• pp.326-334
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• 2020

Background: In this study, we sought to evaluate whether systemic propentofylline (PPF) has antiallodynic effects in a rat model of postoperative pain, and to assess the mechanism involved. Methods: After plantar incision, rats were intraperitoneally injected with various doses of PPF to evaluate its antiallodynic effect. To investigate the involved mechanism, rats were intraperitoneally injected with yohimbine, dexmedetomidine, prazosin, naloxone, atropine or mecamylamine, following the incision of the rat hind paws, and then PPF was administered intraperitoneally. The mechanical withdrawal threshold (MWT) was evaluated using von Frey filaments at various time points and serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were measured to determine the inflammatory response level. Results: MWT was significantly increased after intraperitoneal injection of 30 mg/kg of PPF when compared with the control group. Injection of PPF and yohimbine, atropine or mecamylamine showed significant decreases in the MWT, while injection of PPF and dexmedetomidine showed a significant increase. Systemic administration of PPF inhibited the post-incisional increase in serum level of TNF-α and IL-1β. Conclusions: Systemic administration of PPF following surgery presented antiallodynic effects in a rat model of postoperative pain. The antiallodynic effects against mechanical allodynia could be mediated by α-adrenergic and cholinergic receptors.