• Journal of the Korean Institute of Educational Facilities
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• v.28 no.4
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• pp.11-17
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• 2021

This study is aimed at presenting an efficient management plan of user participatory design in a situation where the School Space Innovation Project is in progress. 2 schools that were the targets of the Incheon School Space Innovation Project in 2019 were selected for this, and features such as the physical environment of that classroom, classroom usage plan, and the stepwise outcome of the user participatory design workshop were contemplated. Especially the workshop outcome was compared and analyzed quantitatively, focusing on the actual master plan and zoning plan, in order to identify the feature that opinions of various users are reflected on the actual plan. As a result, the following conclusion could be reached. Firstly, it was confirmed that the expression about the user preferential space influences the classroom usage plan of that classroom. Vague expressions about the whole space held a large majority of the objects for the linguistic expression of the preferential space. The expression mode as limited as the expression of the actions that users want to carry out in the space. On the other hand, when the usage purpose of the classroom was definite, it was confirmed that the demand for furniture·facility is relatively high. Secondly, according to the analysis of zoning for each function, it seems that the stereotype, which is arranged on the basis of the chalkboard at the front of existing classrooms, was applied in the case of the learning zone. However, in cases of other functions, a tendency was identified that the user carries out an image description that reflects the physical features of the space. Sufficient preparation will need to precede for the efficient management of the user participatory design workshop and the acceptance of various opinions. It seems that especially the classroom usage plan, number of workshops, consultation of each step, and the education about the space expression mode affect the master plan.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.83-89
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• 2001

Most technologies of reduction process used in the heat treatment of existent metal products are related to metals applied to bolts and parts of automobiles, and nonmetal such as copper. Heating conditions and reduction gases produced in above processes depend on types of products to be treated thermally but heating systems employ electricity commonly and the reduction gases are separated into additional production equipment and a gas dryer and inefficiently provided into the system. Electrical heating system has the advantage of convenient temperature-control but is not economical because of disadvantages of high electricity-running cost and extra installation cost of a transformer. Accordingly, development of the system which has economical heating mode in which provision of reduction gas and heating conditions are unified is necessary for improvement of economy and efficiency in current reduction processes. This study aimed to develop a new advanced heat treatment furnace using catalytic combustion. thereby minimizing the cost during heating, supplying heat and reductive gas at the same time and controlling operating condition freely by changing electrical heating system to heating system by the gas combustion and regeneration of wasted heat.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.36-42
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• 2007

Diesel PM can be controlled using Diesel Particulate Filter, which can effectively reduce the level of soot emissions to ambient background levels. In the Heavy Duty Diesel area, the Continuously Regeneration trap has been widely applied in the retrofit market. As the Special act for the improvement of air quality in the capital area, the retrofit program for DPF to used diesel vehicle has progressed favorably and there are currently over 1,000 of these DPF in use in retrofit applications in korea. These DPF comprise a specially formulated Diesel Oxidation Catalyst upstream of a DPF. The $NO_2$ generated by the DOC is used to combust the carbon collected in the DPF at low temperature. To certificate DPF device that is suitable to domestic circumstances, it is necessary to evaluate exactly the DPF devices according to the regulation of DPF certificate test procedure for retrofit(ministry of environment(MOE) announcement NO. 2005-16). To do so the understand of that regulation like the standard of PM reduction rate is needed. In this study the test procedure including test cycle and BPT test condition was examined and also the test result for specific DPF was analyzed. In every test like field test, PM reduction efficiency test and seoul-10 mode test, no defect could be showed.

• Journal of Power Electronics
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• v.15 no.2
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• pp.411-418
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• 2015

In this paper, a new method for the online estimation of equivalent series resistances (ESR) of the DC-link capacitors in induction machine (IM) drive systems with a front-end diode rectifier is proposed, where the ESR estimation is conducted during the regenerative operating mode of the induction machine. In the first place, a regulated AC current component is injected into the q-axis current component of the induction machine, which induces the current and voltage ripple components in the DC-link. By processing these AC signals through digital filters, the ESR can be estimated by a recursive least squares (RLS) algorithm. To acquire the AC voltage across the ESR, the DC-link voltage needs to be measured at a double sampling frequency. In addition, the ESR current is simply reconstructed from the stator currents and switching states of the inverter. Experimental results have shown that the estimation error of the ESR is about 1.2%, which is quite acceptable for condition monitoring of the capacitor.

• Journal of Environmental Science International
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• v.18 no.6
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• pp.645-654
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• 2009

Lab-scale Electrodialysis(ED) system with different membranes combined with before or after pyroma process were carried out to remove nitrate from two pickling acid wastewater containing high concentrations of $NO_3\;^-$(${\approx}$150,000 mg/L) and F($({\approx}$ 160,000 mg/L) and some heavy metals(Fe, Ti, and Cr). The ED system before Pyroma process(Sample A) was not successful in $NO_3\;^-$ removal due to cation membrane fouling by the heavy metals, whereas, in the ED system after Pyroma process(Sample B), about 98% of nitrate was removed because of relatively low $NO_3\;^-$ concentration (about 30,000 mg/L) and no heavy metals. Mono-selective membranes(CIMS/ACS) in ED system have no selectivity for nitrate compared to divalent-selective membranes(CMX/AMX). The operation time for nitrate removal time decreased with increasing the applied voltage from 10V to 15V with no difference in the nitrate removal rate between both voltages. Nitrate adsorption of a strong-base anion exchange resin of $Cl\;^-$ type was also conducted. The Freundlich model($R^2$ > 0.996) was fitted better than Langmuir mode($R^2$ > 0.984) to the adsorption data. The maximum adsorption capacity ($Q^0$) was 492 mg/g for Sample A and 111 mg/g for Sample B due to the difference in initial nitrate concentrations between the two wastewater samples. In the regeneration of ion exchange resins, the nitrate removal rate in the pickling acid wastewater decreased as the adsorption step was repeated because certain amount of adsorbed $NO_3\;^-$ remained in the resins in spite of several desorption steps for regeneration. In conclusion, the optimum system configuration to treat pickling acid wastewater from stainless-steel industry is the multi-processes of the Pyroma-Electrodialysis-Ion exchange.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.451-463
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• 2001

Following the extensive use of implant, the incidence of peri-implantitis increases. Guided bone regeneration has been used for the optimal treatment of this disease. Because implant surface was contaminated with plaque and calculus, cleaning and detoxification were needed for the reosseointegration when guided bone regeneration was performed. Various mechanical and chemical methods have been used for cleaning and detoxification of implant surface, air-powder abrasive and oversaturated citrate were known to be most effective among these methods. However, these methods were incomplete because these could not thoroughly remove bacteria of implant surface, moreover deformed implant surface. Recent studies for detoxification of the implant surface using laser were going on, $CO_2$ laser and Soft Diode laser were known to be effective among these methods. The purpose of this study was to obtain clinical guide by application these laser to implant surface. 15 experimental machined pure titanium cylinder models were fabricated. The $CO_2$ laser treatment under dry, wet and hydrogen peroxide condition or the Soft Diode laser treatment under Toluidine blue O solution condition was performed on the each of models. Each groups were examined with SPM and SEM to know whether their surface was changed. The results were as follows : 1. Surface roughness and surface form weren't changed when $CO_2$ laser was usedunder dry condition(P>0.05). 2. Surface roughness and surface form weren't changed when $CO_2$ laser was used under wet condition(P>0.05). 3. Surface roughness and surface form weren't changed when $CO_2$ laser was used under hydrogen peroxide condition(P>0.05). 4. Surface roughness and surface form weren't changed when Soft Diode laser was used under toluidine blue O solution condition(P>0.05). From the result of this study, it may be concluded that the $CO_2$ laser having relatively safe pulse mode and the Soft Diode laser used with photosensitizer can be used safely to treat peri-implantitis.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.205-213
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• 2002

This paper deals with the implementation of three-phase VSI systems which can control the power regenerated from DC bus line to AC supply. The overall system consists of the line-to-line voltage and line current sensors, an actual power calculator using d-q transformation method, a complex power controller with PI control scheme, a gating signal generator for modified ｑ-conduction mode, a DPLL for frequency followup, and Power circuits. Control board is constructed by using a 32-bit DSP TMS32C32, two EFLDs , six ADCs, and a DAC. To verify the performance of the proposed system, we designed and constructed the propotype with the power rating of 5kVA at AC 220V. Experimental results show that the regenerated active power is well controlled to its command vague and the regenerated reactive power still remained at nearly zero through all operating modes.

• Journal of Oral Medicine and Pain
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• v.18 no.2
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• pp.97-106
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• 1993

This study was performed to investigate the effects of infrared and visible light laser irradiation on cell viability of human gingival fibroblast. For the present study, the author used cultured fibroblast originated from sound gingiva which were fifth of sixth passage. Laser machine utilized here were stomalaser which irradiate infrared (GaAs diode) and red (HeNe) laser in turn with pulse wave pattern or continuous wave pattern, and the machine had several frequency mode presented by regeneration, relaxation and analgesic modalities. Cultured fibroblast samples were divided by this modalities of cell counts and laser exposure time which were 7-seconds of 150 seconds, respectively. 1 day after laser irradiation, each cell-well was treated with MTT and measured optical density with ELISA. The obtained results were as follows : 1. There was a tendency of increasing optical density in proportion to irradiation time in groups of $1\times10^4$ cell per well but in groups of $5\times10^3$ cell per well, reverse phenomena were observed. 2. The difference of optical density according to frequency modalities were not showed significantly except several cases in groups of $5\times10^3$ cell per well. 3. In general, cell viability of cultured human gingival fibroblast wer not showed consistent feature by low level laser irradiation.

• Journal of Ginseng Research
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• v.34 no.2
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• pp.77-88
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• 2010

Ginseng has been reported to reduce the risk of cancer in diverse organs, including the lip, oral cavity, pharynx, larynx, esophagus, lung, liver, pancreas, ovary, colon, rectum, and stomach, as demonstrated in clinical and epidemiological studies. studies, base on which findings, Panax ginseng has been classified as a "non-organ-specific cancer preventive." However, the recent keen interest in traditional medicinal herbs has been frequently questioned, about exact mode of action and the use of panaceic compounds has been a prime issue discussed in terms of complementary and alternative medicine. Several in vitro and in vivo studies have shown the mitigating effects of Korean red ginseng on Helicobacter pylori (H. pylori)-associated atrophic changes and carcinogenesis; However, evidence-based medicine, consisting of large-scale or well designed clinical studies, is still warranted whether Korean red ginseng is to be recognized as an essential therapeutic strategy regarding a "H. pylori-associated gastric cancer preventive." Specifically, comprehensive clinical trials of Korean red ginseng are needed to demonstrate that mucosal regeneration in patients with atrophic gastritis is feasible using Korean red ginseng supplements after the eradication of H. pylori infection. Ginseng is a good example of a natural herb and its ubiquitous properties may include the reduction or delay of inflammation carcinogenesis. Korean red ginseng contains ample amounts of active ginsenosides and we have demonstrated their effects in in vitro and in vivo studies with positive outcomes. In this review, the quantitative and qualitative benefits of Korean red ginseng in the treatment of H. pylori infection are described.

• KSBB Journal
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• v.22 no.6
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• pp.443-446
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• 2007

A prognostic indicator of coronary heart disease, C-reactive protein, was tried to be determined by a batch-type quartz crystal microbalance immunosensor. The sensor was operated by direct-binding mode and the optimum concentration for the corresponding antibody for immobilization was $50{\mu}g/ml$. The reaction buffer for the system was 0.1 M sodium phosphate (pH 7.0) and system operation was performed in the order of baseline stabilization, analyte addition and measurement, and regeneration of the sensor chip with 10 mM NaOH. When plotted in double-logarithmic scale, the sensor showed a linear detection range of 0.27-106.00 nM for rat C-reactive protein with the limit of detection of 0.53 nM. It also showed a good reusability.