• Journal of the Korean Society for information Management
• /
• v.17 no.4
• /
• pp.207-227
• /
• 2000

Recenily, major internalional STM(Science, Trchnical, and Mcdivine) Publichers have been developing prototype systems that can provide the refeence linking of jouinal articles within the scholarly literature on a cross-publisher basis using the URN(Universal Resouree Name). In Korea, it is hard to find the efforts to link the scattered digitalized documents to an individual user through a unified web. In this study, a linking model for an inergrated gatewny fro, bibliographic information to full tcxt has been desugned and 'Electronic Research Resourced Linking system (E3R/LS)' has been developed as a prototype for centralized static reference linking system. There are three major components for constructing refrernce linking systems. The firsl componcnt the Digital Object Identifiet(DO1). is introduced as the public identifier inrended to be applied wherever thr item needs to be identified. For denl~iymg Korean journal articles, llie extended SICI(Serlal Ilem and Conlribut~on Idealifier) has becn newly dehed in 1111s study and is used as a suiiia on DOI. The reierence datubasc conlams the second com~onenl, metadiltil, linkcd to implemenied by all information providers. The CnRI resolution system is used for resolving a DOI into a URL as the third component.

• Archives of design research
• /
• v.14
• /
• pp.141-150
• /
• 1996

In recent years space planning for modern city has been accomplished through scientific high technique and computer supported collaborative work. Relatively human being is treated as a component of the space or whole building and according to the social structure people tend to prefer private space. The necessity of the open space as an active place is emphasized now because the interaction created between users of the space and the nature, surrounding environment can influence on improving quality of outdoor life and giving the place specific identity. In this paper three ways of analyses of components which compose the open space are studied. Especially through the process of analyses derived from differenet areas, the necessity of communication model in collaborative work is proposed.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.22 no.2
• /
• pp.91-99
• /
• 2014

The common-rail injectors are the most critical component of the CRDI diesel engines that dominantly affect engine performances through high pressure injection with exact control. Thus, from now on the advanced combustion technologies for common-rail diesel injection engine require high performance fuel injectors. Accordingly, the previous studies on the numerical and experimental analysis of the diesel injector have focused on a optimum geometry to induce proper injection rate. In this study, computational predictions of performance of the diesel injector have been performed to evaluate internal flow characteristics for various needle lift and the spray pattern at the nozzle exit. To our knowledge, three-dimensional computational fluid dynamics (CFD) model of the internal flow passage of an entire injector duct including injection and return routes has never been studied. In this study, major design parameters concerning internal routes in the injector are optimized by using a CFD analysis and Response Surface Method (RSM). The computational prediction of the internal flow characteristics of the common-rail diesel injector was carried out by using STAR-CCM+7.06 code. In this work, computations were carried out under the assumption that the internal flow passage is a steady-state condition at the maximum needle lift. The design parameters are optimized by using the L16 orthogonal array and polynomial regression, local-approximation characteristics of RSM. Meanwhile, the optimum values are confirmed to be valid in 95% confidence and 5% significance level through analysis of variance (ANOVA). In addition, optimal design and prototype design were confirmed by calculating the injection quantities, resulting in the improvement of the injection performance by more than 54%.

• Journal of Astronomy and Space Sciences
• /
• v.33 no.3
• /
• pp.185-196
• /
• 2016

New multiband BVRI light curves of NSVS 1461538 were obtained as a byproduct during the photometric observations of our program star PV Cas for three years from 2011 to 2013. The light curves indicate characteristics of a typical W-subtype W UMa eclipsing system, displaying a flat bottom at primary eclipse and the O'Connell effect, rather than those of an Algol/b Lyrae eclipsing variable classified by the northern sky variability survey (NSVS). A total of 35 times of minimum lights were determined from our observations (20 timings) and the SuperWASP measurements (15 ones). A period study with all the timings shows that the orbital period may vary in a sinusoidal manner with a period of about 5.6 yr and a small semi-amplitude of about 0.008 day. The cyclical period variation can be interpreted as a light-time effect due to a tertiary body with a minimum mass of 0.71 M_⊙. Simultaneous analysis of the multiband light curves using the 2003 version of the Wilson-Devinney binary model shows that NSVS 1461538 is a genuine W-subtype W UMa contact binary with the hotter primary component being less massive and the system shows a low mass ratio of q(m_c/m_h)=3.51, a high orbital inclination of 88.7°, a moderate fill-out factor of 30 %, and a temperature difference of ΔT=412 K. The O'Connell effect can be similarly explained by cool spots on either the hotter primary star or the cool secondary star. A small third-light corresponding to about 5 % and 2 % of the total systemic light in the B and V bandpasses, respectively, supports the third-body hypothesis proposed by the period study. Preliminary absolute dimensions of the system were derived and used to look into its evolutionary status with other W UMa binaries in the mass-radius and mass-luminosity diagrams. A possible evolution scenario of the system was also discussed in the context of the mass vs mass ratio diagram.

• Journal of Sensor Science and Technology
• /
• v.18 no.4
• /
• pp.286-293
• /
• 2009

The implantable middle ear hearing devices(IMEHDs) have been developed to overcome the conventional hearing aid's problem(ringing effect caused by the acoustic feedback, cosmetic problem, etc.). In the IMEHDs, the vibrating transducer is a key component because its vibration enables to hear for hearing impaired people. The vibrating transducer is implanted on ossicular chain by surgical operation. The coupling status between implanted transducer and ossicular chain has an effect on delivering vibrating force from transducer to stapes. Noninvasive method is required to investigate the output characteristics of IMEHDs after implementation. Recently, emitted sound pressure measuring method of tympanic membrane is proposed to investigate the output characteristics of IMEHDs. However, the relationship between displacement of stapes and sound pressure by tympanic membrane was not cleared. In this paper, displacement of stapes and sound pressure by tympanic membrane were measured using the differential floating mass transducer(DFMT) that implanted on the ossicular chain of the human temporal bone and physical ear model. Through the experiments results, the relationship between displacement of stapes and sound pressure by tympanic membrane was investigated.

• Journal of radiological science and technology
• /
• v.40 no.1
• /
• pp.135-142
• /
• 2017

Selenium (Se), which is natural materials existing was known as an important component of selenoprotein, one of the important proteins responsible for the redox pump of a living body. Selenium was orally administered to Rat and irradiated with 10 Gy of radiation. Then, the thyroid gland was used as a target organ for 1 day, 7 days and 21 days to investigate the radiation protection effect of selenium (Se) through changes of blood components, thyroid hormones (T3, T4), antioxidant enzyme (GPx) activity and thyroid tissue changes. As a result, there was a significant protective effect of hematopoietic immune system(hemoglobin concentration, neutrophil, platelet)(p<0.05). The activity of Glutathione Peroxidase (GPx), the antioxidant enzyme, and the activity of the target organ, thyroid hormone (T3, T4), also showed significant activity changes (p<0.05). In the observation of tissue changes, it was confirmed that there was a protective effect of thyroid cell damage which caused the cell necrosis by radiation treatment. Therefore, it is considered that selenium(Se) can be utilized as a radiation defense agent by inducing immunogenic activity effect of a living body.

• The Journal of the Petrological Society of Korea
• /
• v.4 no.1
• /
• pp.49-58
• /
• 1995

Staurolite-biotite-andalusite-garnet (SBAG) assemblage and its sub-assemblages (SBA and SBG) commonly occur in the Dueumri Formation near the Chunyang granite, belonging to andalusite and sillimanite zones. The occurrence of the SBAG mineral assemblage is unusual because it is univariant in the $K_2O-FeO-MgO-Al_2O_3-SiO_2-H_2O$ (KFMASH) model system. We used projection and singular value decomposition (SVD) methods to investigate the equilibrium relationship between SBAG and its sub-assemblage. The SVD modelling of single specimen containing the SBAG assemblage suggests no reaction relationship with respect to mass-balance. Thus, the SBAG assemblages are stabilized by non-KFMASH component. On the other hand, the AFM-Mn projection suggests a reaction relationship between SBAG and its sub-assemblage because they intersect each other in this composition space. The SVD modelling, however, suggests no reaction relationship between these assemblages. Thus, the SBAG assemblages are likely to be stabilized by the variation in bulk-rock composition and/or 1.1~2,. The stable occurrence of staurolite in the sillimanite zone is compatible with pressure estimates from the garnet-plagioclase-biotite-muscovite geobarometer.

• Korean Journal of Soil Science and Fertilizer
• /
• v.14 no.4
• /
• pp.179-184
• /
• 1982

To describe a mathematical heat transfer model in saturated paddy soils, an analytical solution of the heat flow equation incorporated with the heat transfer by mass flow of water was obtained under the assumptions: 1) the diurnal (or annual) changes in temperature at a depth follow harmonic curves, 2) the temperature at the infinite depth be constant and 3) the temperatures of soil and water at the one depth be identical. The calculation of thermal diffusivities of the soil is possible with the known values of the physical parameters of each component in the soil matrix (heat capacity, density and porosity), percolation rate and the minimum and maximum temperatures at two different depths. The calculated thermal diffusivities using the solution were $9.5cm^2/hr$ for the loam soil with the percolation rate of 0.88cm/day and $13.9cm^2/hr$ for the sandy loam soil with the percolation rate of 2.64 cm/day.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.11
• /
• pp.1499-1506
• /
• 2011

The IHX (intermediate heat exchanger) is a key component of nuclear hydrogen systems for the production of massive amounts hydrogen. The IHX transfers the $950^{\circ}C$ heat generated by the VHTR (very high temperature reactor) to a hydrogen production plant. The Korea Atomic Energy Research Institute established a small-scale gas loop to test the performance of key VHTR components and manufactured a small-scale PCHE (printed circuit heat exchanger) prototype, which is being considered as a candidate for the IHX, for testing in the small-scale gas loop. In this study, as a part of the high-temperature structural integrity evaluation of the small-scale PCHE prototype, we carried out high-temperature structural analysis modeling and macroscopic thermal and structural analysis for the small-scale PCHE prototype under the small-scale gas loop test conditions. This analysis serves as a precedent study to scheduled PCHE performance test in the small-scale gas loop. The results obtained in this study will be compared with the test results for the small-scale PCHE and then used to design the medium-scale PCHE prototype.

• Korean Journal of Microbiology
• /
• v.52 no.3
• /
• pp.365-374
• /
• 2016

In high-latitude regions, temperature has risen ($0.6^{\circ}C$ per decade) and this leads to the increase in microbial degradability against soil organic carbon (SOC). Furthermore, the decomposed SOC is converted into green-house gases ($CO_2$ and $CH_4$) and their release could further increase the rate of climate change. Thus, understanding the microbial diversity and their functions linked with SOC degradation in soil-thawing model is necessary. In this study, we divided tundra soil from Council, Alaska into two depth regions (30-40 cm and 50-60 cm of depth, designated as SPF and PF, respectively) and incubated that for 108 days at $0^{\circ}C$. A total of 111,804 reads were obtained through a pyrosequencing-based metagenomic study during the microcosm experiments, and 574-1,128 of bacterial operational taxonomic units (OTUs) and 30-57 of archaeal OTUs were observed. Taxonomic analysis showed that the distribution of bacterial taxa was significantly different between two samples. In detail, the relative abundance of phyla Actinobacteria and Firmicutes largely increased in SPF and PF soil, respectively, while phyla Crenarchaeota was increased in both soil samples. Weight measurement and gel permeation chromatography of the SOC extracts demonstrated that polymerization of humic acids, main component of SOC, occurred during the microcosm experiments. Taken together our results indicate that these bacterial and archaeal phyla could play a key function in SOC degradation and utilization in cold tundra soil.