• Journal of the Korean Society of Combustion
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• v.5 no.2
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• pp.19-27
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• 2000

A turbulent combustion model, based on edge flame dynamics, is discussed in order to predict global extinction of turbulent flames. The model is applicable to the broken flamelet regime of turbulent combustion, in which global extinction of turbulent flame is achieved by gradual expansion of flame holes. The edge flame dynamics is the key mechanism to describe the flame hole expansion or contraction. For flames with Lewis numbers near unity, there is a $Damk{\ddot{o}}hler$ number, namely the crossover $Damk{\ddot{o}}hler$ number, at which edge flame changes its direction of propagation. The parametric region between the quasi-steady extinction condition and the edge-flame crossover condition is a metastable region, in that flames without edge can stay in their burning states while flames with edge have to retract to expand quenching holes. Using the above properties of edge flame, Hartley and Dold proposed a Lagrangian hole dynamics, which allows us to simulate transient variation of quenching holes. In their model, each stoichiometric surface is subjected to a random sequence of scalar dissipation rate compatible to the equilibrium turbulence. Then, each stoichiometric surface will evolve, according to the combustion map, dependent on the scalar dissipation rate and existence of flame edge, If all the burning surfaces are annihilated, the event can be declared as a global extinction. The consequence obtained from the above model also can be used as a subgrid model to determine local extinction occurring in a calculation grid.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.379-381
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• 2014

Influence of fuel concentration gradient was investigated near flame extinction limit in buoyancy-suppressed non-premixed counterflow flame with triple co-flow burner. The use of He curtain flow produced a microgravity level of $10^{-2}-10^{-3}g$ in He-diluted non-premixed counter triple co-flow flame experiments. Flame stability map was presented based on flame extinction and oscillation near extinction limit. The stability map via critical diluent mole fraction with global strain rate was represented by varying outer and inner He-diluted mole fractions. The flame extinction modes could be classified into five: an extinction through the shrinkage of the outmost edge flame forward the flame center with and without self-excitation, respectively ((I) and (II)), an extinction via the rapid expansion of a flame hole while the outmost edge flame is stationary (III), both the outermost and the center edge flames oscillate, and then a donut shaped flame is formed or the flame is entirely extinguished (IV), a shrinkage of the outermost edge flame without self-excitation followed by shrinking or sustain the inner flame (V).

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.74-82
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• 2020

Predictions of suitable habitat areas can provide important information pertaining to the risk assessment and management of alien plants at early stage of their establishment. Here, we predict the invasion potential of Muhlenbergia capillaris (pink muhly) in South Korea using five bioclimatic variables. We adopt four models (generalized linear model, generalized additive model, random forest (RF), and artificial neural network) for projection based on 630 presence and 600 pseudo-absence data points. The RF model yielded the highest performance. The presence probability of M. capillaris was highest within an annual temperature range of 12 to 24℃ and with precipitation from 800 to 1,300 mm. The occurrence of M. capillaris was positively associated with the precipitation of the driest quarter. The projection map showed that suitable areas for M. capillaris are mainly concentrated in the southern coastal regions of South Korea, where temperatures and precipitation are higher than in other regions, especially in the winter season. We can conclude that M. capillaris is not considered to be invasive based on a habitat suitability map. However, there is a possibility that rising temperatures and increasing precipitation levels in winter can accelerate the expansion of this plant on the Korean Peninsula.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.183-188
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• 2001

Topographic map is important for the additional detailed construction planning followed by slope sliding. It is a base map that is used to compute the volume of soil, the cost of construction, and check the stability in the area of slope sliding. In this study, 3D topographic data were acquired appling softcopy photogrammetry to the dangerous slope, and the method which can transform these data to the same coordinates system as early TM coordinates was designed. There was a problem when the one meter contour line was made by analysing the image taken from the distance three hundred meters. By solving this problem, this could be used as important data for the planning of road expansion construction. It is expected to be useful for the measurement of various dangerous area in civil engineering works.

• Korean Journal of Geomatics
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• v.2 no.1
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• pp.83-89
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• 2002

The cadastral maps as many as about 750,000 map sheets to cover 34,751,000 parcels of land of Korea, are being digitalized. The problem of shrinkage-expansion of the paper cadastral maps has to be resolved for the new digital maps, where the nodes and vertices of the parcel boundaries are represented by coordinates. The photo coordinate refinement techniques, two dimensional projective transformation and local area transformation as in the reseau grid method, were introduced for this distortion correction. Using the fact that original maps drawn on the plane tables in field from 1910 to 1918 have grid lines and have been preserved well, a strategic flow to apply the refinement techniques to the digital maps with the original maps as controls was developed. To accommodate the presence or absence of the original maps and grid lines, and different scales and sizes of the maps, the strategy was implemented by a computer program package. Various distortions and corrections were simulated and errors were evaluated. The RMS errors in the corrected digital maps were allowable, thus, the method developed in this study was to be applicable for the digital cadastral maps.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.635-638
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• 2009

ENC Optimizer S/W was developed for light weight, ENC speed improvement, nested data, and optimization of the data module. ENC optimizer customize based on Korea Ocean's ENC data by Investigators of the National Marine.Based on the modification of K-Map ENC through enhancemen to fENC Web OCX module and ENC Optimizier, AIS service by WebWM Shad been developed. WebVMS make it possible to view the ship information anywherevia WebBrowser. Later, through the expansion of the surveillance ship WebVMS the past, information about access, satellite communications, tracking and monitoring are currently used invarious applications such as shipping informationis available.

• Electronics and Telecommunications Trends
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• v.36 no.1
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• pp.109-119
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• 2021

The Korean government recently announced a plan of the Carbon Neutral policy in addition to the Green New Deal of the Korean New Deal and the Renewable Energy 3020. The energy sector is entering the era of major transformation involving the expansion of decarbonization, decentralization, and digitalization. DNA-oriented ICT technology will be incorporated into the sector. Further, new energy industries and services are being realized via efficient and smart operation and by appropriately managing the energy-environment changes. Recently, ETRI presented a technology development map for 2035 comprising 12 new concepts in four major fields(personal, social, industrial and public) of national intelligence. This map includes the concept of "Energy Maestro" associated with the field of public intelligence for human sustainability. This paper briefly introduces this concept and ETRI's Energy-R&D status. Based on the domain knowledge and the experience acquired through the R&D, ETRI will lead to a new paradigm with respect to the creation of new energy services and industries via the incorporation of the new ICT technologies including AI and big-data into the energy sector.

• Journal of Ecology and Environment
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• v.48 no.1
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• pp.8-16
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• 2024

The integration and management of various national ecological assessments are essential for the benefit of the public. In the Republic of Korea, the Ecological and Natural Map (ENM) serves as a comprehensive platform that synthesizes the results of national ecosystem surveys into a unified system interface. To provide the current status and characteristics of our policy, we analyzed the ENMs and related appeals from 2014 to 2022. Following their implementation, the ENM Guidelines underwent nine revisions, with most of the revisions pertaining to appeals. Nine public announcements were made regarding the ENM, resulting in a gradual expansion of the conservation area. The data also showed a consistent increasing trend in appeals. Most of the 1st-grade areas in the ENM regions where appeals were filed have significantly decreased. The larger area or the smaller population density of an administrative distinct, the more appeals were filed. Our study presents information regarding the current status of the ENM system. The analysis of the operational direction and indicator trends across the 16-year period since the establishment of the system provides valuable insights for similar systems.

• Journal of Life Science
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• v.13 no.3
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• pp.280-290
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• 2003

The incorporation of RAPD markers into the previous classical and RFLP genetic linkage maps will facilitate the generation of a detailed genetic map by compensating for the lack of one type of marker in the region of interest. The objective of this paper was to present features we observed when we associated RAPD map from an intraspecific cross of a Glycine max$\times$G. max, 'Essex'$\times$PI 437654 with the public RFLP map developed from an interspecific cross of G. max$\times$G. soja. Among 27 linkage groups of RAPD map, eight linkage groups contained probe/enzyme combination RFLP markers, which allowed us the incorporation of RAPD markers into the public RFLP map. Map position rearrangement was observed. In incorporating L.G.C-3 into the public RFLP linkage group a1 and a2, both pSAC3 and pA136 region, and pA170/EcoRV and pB170/HindIII region were in opposite order, respectively. And, pk400 was localized 1.8 cM from pA96-1 and 8.4 cM from pB172 in the public RFLP map, but was localized 9.9 cM from i locus and 18.9 cM from pA85 in our study. A noticeable expansion of the map distances in the intraspecific cross of Essex and PI 437654 was also observed. Map distance between probes pA890 and pK493 in L.G.C-1 was 48.6 cM, but it was only 13.3 cM in the public RFLP map. The distances from the probe pB32-2 to pA670 and from pA670 to pA668 in L.G. C-2 were 50.9 cM and 31.7 cM, but they were 35.9 cM and 13.5 cM in the public RFLP map. The detection of duplicate loci from the same probe that were mapped on the same or/and different linkage group was another feature we observed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.25-33
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• 2020

A drought event is characterized by duration, severity and affected area. In general, after calculating a drought index using hydro-meteorological time series at a station, a drought event is defined based on the run theory to identify the beginning and end time. However, this one-dimensional analysis has limitations for analyzing the spatio-temporal occurrence characteristics and movement paths of drought. Therefore, this study is to define a three-dimensional drought event using a simple clustering algorithm and to develop a drought map that can be used to understand the drought severity according to the spatio-temporal expansion of drought. As a result, compared with the two-dimensional monitoring information to show spatial distribution of drought index, a proposed drought map is able to show three-dimensional drought characteristics inclusing drought duration, spatial cumulative severity, and centroid of drought. The analysis of drought map indicated that there was a drought event which had the affected area less than 10 % while on occations while there were 11 drought events (44 %) which had the affected area more a than 90 % of the total area. This means that it is important to understand the relationship between spatial variation of drought affected area and severity corresponding to various drought durations. The development of drought map based on three-dimensional drought analysis is useful to analyze the spatio-temporal occurrence characteristics and propagation patterns of regional drought which can be utilized in developing mitigation measures for future extreme droughts.