• Journal of Environmental Science International
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• v.29 no.8
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• pp.827-835
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• 2020

Zeolite material having XRD peaks of Na-A zeolite in the 2θ range of 7.18 to 34.18 can be synthesized from the waste catalyst using a fusion/hydrothermal method. The adsorption rate of Mn ions by a commercial Na-A zeolite and the synthesized zeolitic material increased as the adsorption temperature increased in the range of 10 ~ 40℃. The adsorption of Mn ion were very rapid in the first 30 min and then reached to the equilibrium state after approximately 60 min. The adsorption kinetics of Mn ions by the commercial Na-A zeolite and the zeolitic material were found to be well fitted to the pseudo-2^nd order kinetic model. Equilibrium data by the commercial Na-A zeolite and the zeolitic material fit the Langmuir, Koble-Corrigan, and Redlich-Peterson isotherm models well rather than Freundlich isotherm model. The removal capacity of the Mn ions by the commercial Na-A zeolite and the zeolitic material obtained from the Langmuir model was 135.2 mg/g and 128.9 mg/g at 30℃, respectively. The adsorption capacity of Mn ions by the synthesized zeolitic material was almost similar to that of commercial Na-A zeolite. The synthesized zeolitic material could be applied as an economically feasible commercial adsorbent.

• The korean journal of orthodontics
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• v.9 no.1
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• pp.99-103
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• 1979

For the purpose of investigating the response of the periodontal tissue in relation to the experimental tooth movement, the rats were inhibited from collagen formation by adminstration of aminoacetonitrile. Findings were as follows: 1) In experimental group, the principal fibers of the periodontal ligament came to run parallel along the alveolar bone or root surface on the pressure side, while the decrease in density, irregular arrangement, and partial loss of principal fibers were observed on the tension side. 2) Sharpey's fibers at the alveolar bone decreased in number, and as the aminoacetonitrile administration continued, the capability of matrix formation decreased on the tension side, the narrowing of the alveolar septum and poor-bony trabeculation appeared on the pressure side. 3) In cementum, Sharpey's fibers were distributed irregularly. The formation of acellura cementum was decreased on the tension side, while the formative capability of cellular cementum was increased. 4) The degree of staining by Herovici technique decreased in the periodontal membrane. By PAS and ninhydrine -Schiff reaction it was appeared weakly positive in the region where the Sharpey's fibers existed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.1-8
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• 2010

It is required to polish the components of administrative services constructively and technologically in order to achieve adminstration the u-Gov pursues. Therefore, the government needs to provide management on united information by combining collaborative construction and Convergence technology. This is called to be UT based positioning system. The system ought to be spread out and is contributed to enlarge interaction. For these reasons, in this paper, I embodied the fundamental st겨cture of new the service application through drawing UT based requirements for an establishment of its prototype.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1314-1317
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• 1999

In this paper, we design an Adaptive Neuro-Fuzzy Inference System(ANFIS) Precompensator for the performance improvement of conventional proportional integral derivative (PID) controller that the governor system of power plant constantly maintains the load frequency of two-area power system. The ANFIS Precompensator is expressed as the membership functions of premise parameters and the linear combination of consequent parameters by Sugeno's fuzzy if-then rules using nonlinear input-output relation for the set point automatic modification maintaining conventional PID controller. The proposed compensation design technique is hoped to be satisfactory method overcome difficulty of exact modelling and arising problems by the complex nonlinearities of power system, and our design shows merit that is easily implemented by adding an ANFIS precompenastor to an existing PID controller without replacement.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.299-308
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• 2018

The adsorption characteristics of Cu ions were studied using the zeolite Na-A synthesized from Jeju volcanic rocks. The effects of various operating parameters such as initial concentration of Cu ions, contact time, solution pH, and solution temperature were investigated in batch experiments. The adsorption of Cu ions by Na-A zeolite was fitted well by pseudo-second-order kinetics and the Langmuir isotherm model. The maximum adsorption capacity determined using the Langmuir isotherm model was 152.95 mg/g. In addition, the adsorption of Cu ions by zeolite Na-A was primarily controlled by particle diffusion model in comparison with the film diffusion model. As the temperature increased from 303 K to 323 K, ${\Delta}G^o$ decreased from -2.22 kJ/mol to -3.41 kJ/mol, indicating that the adsorption of Cu ions by Na-A zeolite is spontaneous process.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1485-1491
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• 2016

PSf/D2EHPA/CNT beads were prepared by immobilizing di-(2-ethylhexyl)-phosphoric acid (D2EHPA) and carbon nanotubes (CNT) on polysulfone (PSf) and used to remove Cu(II) from aqueous solutions. Optimum pH was in the range of 4 to 6. The removal kinetic of Cu(II) by the prepared PSf/D2EHPA/CNT beads was mainly governed by internal diffusion, and the diffusion coefficient of Cu(II) by PSf/D2EHPA/CNT beads was found to be $2.19{\times}10^{-4}{\sim}2.64{\times}10^{-4}cm^2/s$. The Langmuir isotherm model predicted the experimented data well. The maximum removal capacity of Cu(II) obtained from this isotherm was 7.32 mg/g. Calculated thermodynamic parameters such as ${\Delta}G^o$, ${\Delta}H^o$ and ${\Delta}S^o$ showed that the adsorption of Cu(II) ions onto PSf/D2EHPA/CNT beads was feasible, spontaneous and endothermic at 293-323 K.

• The Korean Journal of Air & Space Law and Policy
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• v.5
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• pp.321-384
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• 1993

The paper is to study and analyze the civil aviation industry of China and to present some cooperative and developing models between Korea and China in the fields of civil aviation on the basis of mutul benefit. In this study, civil aviation includes both the air transport industry and aircraft manufacturing industry. As it is not easy and realistic for us to conduct field survey on the civil aviation of China so far, this study has havily depended upon the literature data gathered from the ICAO and other published materials. This study includes the following major contents. 1. The historical development of China civil aviation 2. The present status and future prospect of Civil Aviation Adminstration of China(CAAC) 3. The present status of Chinese aircraft industry 4. Administration of airport and airspace of China 5. Air transport industry of China 6. The design of Korea-China civil aviation cooperation

• Spatial Information Research
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• v.10 no.1
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• pp.15-27
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• 2002

GIS has recognized as the Social Overhead Capital to improve national competition and to heighterl the productivity of adminstration in 1990's in Korea. As the size and the scope of the NGIS policy have drastically expanded, evaluation has become a critical process. Thus NGIS driving committee has adopted the GIS project evaluation scheme in NGIS law since 2000. But the HGIS evaluation scheme is not sufficient for the comprehensive appraisal on the GIS project in the Second National GIS Master Plan (2001-2005). This research aims to explore an the improved evaluation scheme of NGIS policy.

• Journal of Sasang Constitutional Medicine
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• v.23 no.1
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• pp.8-11
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• 2011

1. Objectives: Sixty eight kinds of single herbal medicine extracts and fifty six kinds of mixed herbal medicine extracts have been used under a national health insurance since 1987. The number of herbal medicine extracts under an insurance coverage remains unchanged. The demand for covering complex herbal medicine extracts and Sasang Constitutional medicine extracts in a national health insurance increases. This study is to investigate the needs for the insurance coverage. 2. Methods: Advantages and disadvantages between herbal medicine decoction and extracts were explained and Sasang Constitutional medicine extracts according to Sasang constitution were surveyed in production nowadays. 3. Results: Herbal medicine decoction has many advantages of treating patients but herbal medicine extracts have advantages of the rapid adminstration and being easy to carry. From eleven to twenty two products of Sasang Constitutional medicine extracts have been in production in several factories. There are eleven kinds of Soyangin medicine extracts, nine kinds of Taeeumin medicine extracts and five kinds of Soeumin medicine extracts. 4. Conclusions: Complex herbal medicine extracts and Sasang Constitutional medicine extracts have to be in use under a national health insurance as soon as possible.

• Journal of Korean Society of Disaster and Security
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• v.8 no.1
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• pp.29-37
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• 2015

This study is concerned with the estimation of fluctuation wind velocity spectrum and turbulence characteristics in the major cities reflecting the recent meteorological with typhoon wind velocity about 2003 (Maemi) 2010 (Kompasu) 2012 (Tembin). The purpose of this paper is to present spectral analysis for longitudinal component fluctuating velocity. In the processes of analysis, the longitudinal velocity spectrums are compared widely used spectrum models with horizontal wind velocity observations data obtained at Korea Meteorological Adminstration (KMA) and properties of the atmospheric air for typhoon fluctuating wind data are estimated to parameters with turbulency intensity, shear velocity and roughness length.