• 한국연소학회:학술대회논문집
• /
• 2001.06a
• /
• pp.23-30
• /
• 2001

Bomb calorimeter was developed for measuring the calorific value of combustible matter such as wastes. The calorimeter consist of bomb, stirred-water type bucket, thermometer and ignition circuit. Operation and performance of the calorimeter have been tested experimentally. In the present study, calorific values of light oil, lamp oil, benzoic acid, ethyl alcohol and methyl alcohol is measured using the bomb calorimeter. Mass of the sample is fixed at 19, and oxygen pressure in the bomb is used as an experimental parameter. Sample in the oxygen bomb is burned with electrically heated Ni-Cr wire of 100mm in length, and temperature of water in the bucket become increased by $2{\sim}5^{\circ}C$ during about 30min. Calorific value of the sample is calculated with the temperature difference of water. Combustion tests, such as the record of temperature history and the inspection of remnants, are performed at 6, 8 and 10 atm of the oxygen pressure. From the test results, oxygen pressure in the bomb must be over 10atm for complete combustion.

• YAKHAK HOEJI
• /
• v.52 no.4
• /
• pp.293-298
• /
• 2008

Non-steroidal anti-inflammatory drug (NSAID)-induced gut damage and bacterial translocation (BT) have not been studies well, especially from the perspective of time after administration of NSAIDs. We therefore examined these changes in animals. The study was performed on 5 groups of rat; a control group (group A) and diclofenac groups (groups B, C, E, and F). Rats in the diclofenac groups were orally administered diclofenac sodium before intestinal permeability (IP) measurement (group B, 1 h before measurement; group C, 10 h before; group D, 22 h before; and group E, 52 h before). The IP, stool pellet number, serum biochemical profile, enteric bacterial number, and BT in the mesenteric lymph nodes (MLNs), liver, spleen, kidney and heart were measured. The administration of diclofenac resulted in significantly increased IP, caused intestinal protein loss, decreased stool pellet number, caused enteric bacterial overgrowth and increased BT in multiple organs in groups A, B, C, and D. IF, intestinal protein loss, and the BT in the liver and the spleen in group E were decreased than those in group D. There were no differences in the other parameters between group D and E. In the recovery phase of the diclofenac-induced gut damage, enteric bacterial overgrowth and BT in the kidneys and the heart did not change while the BT in the reticuloendothelial systems such as in the MLNs and liver was decreased.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.1742-1746
• /
• 2008

지금까지의 대부분의 2차원 수리해석 모형은 상류와 사류가 혼재된 불연속적인 천이류 흐름을 해석하기에 계산의 정확도 및 현실성에서 많은 문제를 보이고 있으며, 특히 계산과정에서 나타날 수 있는 마른하도의 처리에 있어서 많은 어려움을 겪고 있다. 본 연구의 목적은 유한체적기법을 사용하여 상류와 사류가 혼재하는 불연속적인 하천 천이류를 안정적으로 해석하기 위해 개발된 고정확도 수치모형의 자연하도 적용에 있으며, 또한 마른 하도로 전파되는 흐름 모의 및 계산과정에서 나타날 수 있는 마른하도 처리의 어려움을 해결함으로써 모형의 정확도와 안정성을 검증하여 실제 하천에서의 모형 적용성을 검토함에 있다. 이를 위해 본 연구에서는 흐름의 전파양상을 정확하게 반영할 수 있는 상류이송기법인 Godunov 기법과 관심격자의 좌우 격자 정보를 모두 사용하는 대표적 중앙차분기법인 Beam-Warming 기법의 장점을 모두 반영한 가중평균흐름률 (Weighted Average Flux) 기법을 사용하여 사각격자망의 구성을 통해 자연하도에 적용시킬 수 있는 2차원 유한체적모형을 개발하고자 하였고, 개발된 모형의 안정성, 정확도, 적용성을 검증하기 위해 직사각형 수로, 큰 사행비를 가진 만곡수로에 적용하고, 그 결과를 수리모형 실험결과와 비교, 분석하였다.

• Publications of The Korean Astronomical Society
• /
• v.15 no.spc1
• /
• pp.1-13
• /
• 2000

We review the early historical developement of astronomical spectrographs, properties of emission line spectra of HII regions in spiral galaxies, and absorption line features of galactic globular clusters. Emission line spectra of HII regions within three spiral galaxies NGC 300, NGC 1365, and NGC 7793, which were observed from AAT/IPCS, had been analysed, and we discuss the abundances of elements in HII regions and the radial abundace gradients through the galaxies. The radial UBV color variations of two globular clusters, NGC 1851 and NGC 2808, were examined for correlations with radial variations of several absorption lines in the integrated spectra, which were obtained from SAAO 74 inch telescope and image tube spectrograph. Nine giant star's spectra in NGC 3201 were also obtained and analysed for the radial abundance gradients in the globular cluster. The results show that the presence of a radial color gradient in a globular cluster is correlated with the presence of abundance gradients. Finally, we suggest some scientific programs for the new high dispersion spectrograph, which will be installed to the BOAO 1.8m telescope.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.125-128
• /
• 2008

In the recent construction industry, external tendon method has been widely used for strengthening and repair of civil structures. This paper presents the strengthening effectiveness and application of the proposed external tendons using lifting hole anchorage system. Based on the experimental results of the previous external tendons using lifting hole anchorage systems, two types of modified systems were proposed. In order to verify the strengthening effectiveness of the two systems, six beams were built and a series of experiments was carried out. To compare and analyze the behaviors of the proposed systems, deflections and strains were measured. Additionally, yield load, ultimate load and failure modes were compared and analyzed.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.27 no.1
• /
• pp.39-47
• /
• 2005

The purpose of this study is to review the prognosis of the TG Osseotite implant(3i Co, USA) placed in partial edentulous area of oral cavity and to suspect the possible causes leading to failure. 124 TG Osseotite implants that had been inserted between 2000 - 2002 were followed up for 2 years(avg : 9.5 months) in function. Medical records, and radiographs were evaluated and analyzed by the over all success rate, gender and age factor, general disease, implant fixture length and diameter, implant site, bone density, and various surgical methods. Chi square test was used statistically. Of the 124 TG Osseotite implants, 9 implants(7.3%) were removed in early phase and 3 implants(2.4%) were in late phase. The cumulative survival rate was 90.2%. The failure of the TG Osseotite implant was closely related with the use of bone graft techniques such as sinus elevation or immediate implantation and not with the age, sex, general disease, implant site, bone density of implanted site. The failure of the TG Osseotite implant was well developed when it was the wide type of implant and it was inserted for single tooth replacement. The developement of peri-implantitis was the most important factor in the failure of the TG Osseotite implant.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.6
• /
• pp.237-242
• /
• 2013

There are some limitations to use the fitness center frequently by various reasons, excessive business workload, geographic location and time limit. This research specially focuses on the developement of health care application tool for aerobic/anaerobic exercise in a house accompanied by training coach, simply for the purpose of preventing from a boredom moment by exercing alone. This study newly proposes the realization of program tool by using Microsoft Kinect hardware tool which can be seen easily in the internet stores and can recognize the user. In addition, this program are designed to take care of movement control, weight and calory by maping the perceived user implementing modeling of 3D model.

• Journal of Information Display
• /
• v.7 no.2
• /
• pp.26-30
• /
• 2006

Insertion of a thin lithium fluoride (TLF) layer between an emitting layer (EML) and an electron transporting layer has resumed in the developement of a highly efficient and bright organic light-emitting diode (OLED). Comparing with the performance of the device as a function of position with the TLF layer in tris-(8-hydroxyquinoline) aluminum $(Alq_{3})$, we propose the optimal position for the TLF layer in the stacked structure. The fabricated OLED shows a luminance efficiency of more than 20 cd/A, a power efficiency of 12 Im/W (at 20 mA/$cm^{2}$), and a luminance of more than 22 000 cd/$m^{2}$ (at 100 mA/$cm^{2}$), respectively. We suggest that the enhanced performance of the OLED is probably attributed to the improvement of carrier balance to achieve a high level of recombination efficiency in an EML.

• Korean Chemical Engineering Research
• /
• v.51 no.1
• /
• pp.1-9
• /
• 2013

The transformation of alkylaromatic hydrocarbons using zeolite catalysts play big part in the current petrochemical industry. Here we review recent advances in the understanding of the reaction mechanisms of various alkylaromatic conversions with respect to the structural and physicochemical properties of zeolite catalysts employed. Indeed, the shape-selective nature of zeolite catalysts determines the type of reaction intermediates and hence the prevailing reaction mechanism together with the product distribution. The prospect of zeolite catalysis in the developement of more efficient petrochemical processes is also described.

• Convergence Security Journal
• /
• v.16 no.7
• /
• pp.3-11
• /
• 2016

With repid development of optical networking technology, Software-Defined Network (SDN) and Network Function Virtualization (NFV), high performance networking service, collaboration platform that enables collaborative research globally, drastically National Research Network (NRN) including Internet Service has changed. Therefore we compared and analyzed several world-class NRNs and took a view of future development strategy of the NRN. Also we suggest high speed security environment in super high bandwidth network with 40Gbps and 100Gbps optical transmission technology, network separation of NRN with Science DMZ to support high performance network transmission for science big data, building security environment for last-mile in campus network that supports programmability of IDS using BRO framework.