• Proceedings of the KSME Conference
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• 2000.11b
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• pp.156-161
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• 2000

In this study, quantitative nitric oxide concentration distributions are investigated in the post-flame zone of laminar premixed $CH_4/O_2/N_2$, flames by laser-induced fluorescence (LIF). The measurements are taken in flames for different equivalence ratios varying from $0.8{\sim}1.4$, and flow rate is fixed as 5slpm. The NO A-X (0,0) vibrational band around 226 nm is excited using a XeCl excimer-pumped dye laser. Selecting an appropriate NO transition minimizes interferences from Rayleigh scattering and $O_2$ fluorescence. NO concentration is rised when equivalence ratios increase at different vertical distances form nozzle tip. In any case, the maximum NO concentration reaches the maximum in reaction zone.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.224-229
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• 1996

An experimental study on critical heat flux (CHF) and two-phase flow visualization has been performed for water flow in internally-heated, vertical, concentric annuli under near atmospheric pressure. Tests have been done under stable forced- circulation, upward and downward flow conditions with three test sections of relatively large gap widths (heated length = 0.6 m. inner diameter = 19 mm, outer diameter = 29, 35 and 51 mm). The outer wall of the test section was made up of the transparent Pyrex tube to allow the observation of flow patterns near the CHF occurrence. The CHF mechanism was changed in the order of flooding, chum-to-annular flow transition, and local dryout under a large bubble in churn flow as the flow rate was increased from zero to higher values. Observed parametric trends are consistent with the previous understanding except that the CHF for downward flow is considerably lower than that for upward flow.

• Journal of computational fluids engineering
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• v.4 no.2
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• pp.1-8
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• 1999

Natural convection in a horizontal annulus with the inner cylinder heated by the application of a constant heat flux and the isothermally cooled outer cylinder is considered, and the transition of flows and the bifurcation phenomenon are numerically investigated for air with Pr=0.7. The zero initial condition always induces a crescent-sheped eddy flow. A bicellular flow in which the fluid descends along the vertical central plane of the annulus can be obtained at high Rayleigh number by introducing artificial numerical disturbances. Dual solutions are found above a certain critical Rayleigh number. Hysteresis phenomena have not been observed.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.4
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• pp.33-40
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• 2006

In present study, the principal stress condition needed to conduct cubical large-scale triaxial test which can reflect three dimensional stress condition (or plain strain condition) in a dam was investigated by performing model test and numerical analysis and the principal stress ratio varying with the height of CFRD was examined. Also, the principal stress ratio in CFRD body was investigated from the monitoring results of horizontal and vertical earth pressure gages, installed in the center zone and lower part of transition zone of the dam body, respectively, in order to consider the principal stress condition in the large-scale triaxial test to model the behavior of CFRD. The result of the study indicated that the principal stress ratio decreased gradually from the lower to the upper part in the dam body for its center axis and was about 0.5 and 0.2 in the lower and upper part, respectively.

• Journal of the Korean Chemical Society
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• v.17 no.2
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• pp.80-84
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• 1973

In treating solid-liquid interfaces, it is assumed that the adsorbed layer consists of monolayer and the molecules of the adsorbed layer behave as two dimensional liquid and oscillate harmonically in the vertical direction to the adsorbent. Applying the transition state theory of significant liquid structure to the adsorbed molecules, the adsorption isotherm, entropy and heat of adsorption for cyclohexane-benzene solutions adsorbed on silica-gel G are calculated. The calculated values are in good agreements with those of the observed ones.

• Journal of National Security and Military Science
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• s.5
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• pp.87-130
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• 2007

ROK and the United States finally reached accord on the controversial transition of Wartime Operational Control on February, 2007, and ROK Government needs to strengthen the role of supporting for the comprehensive threats of futuristic warfare. The crucial point of the supporting for Military Operation depends on the nation's mobilization capabilities. For the effective mobilization the following facets can be improved further. First of all, the organizational integrity of the mobilization network within the government can be bolstered along the vertical command chain. The process of mobilization must be improved and it is import to utilize the information system. On the other side the government plan to distribute timely the mobilized resources must be made up for the weak points and developed continuously. We can expect these points to be improved steadily with the execution of the National Defence Reform 2020.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.11
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• pp.1398-1406
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• 2004

The nonlinear signals from an impedance meter for the area average void fraction in two-phase flow have been analyzed to construct a phase space trajectory. The pseudo phase space was constructed with the time delay and proper dimensions. The time delay and the embedding dimension were chosen by the average mutual information and by the false nearest neighborhood, respectively. The attractor-density-map of projected states was used to produce the two dimensional probability distribution functions (2D-PDF). Since the developed 2D-PDF showed clear distinction of the flow patterns, the flow regime identification was made with three rules and with the 2D-PDF. Also, the transition criteria of Mishima-Ishii agree well with the present results.

• Journal of Information Technology Services
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• v.14 no.4
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• pp.221-236
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• 2015

Application software is delivered to customers as a form of service at cloud environment. A cloud service provider is a marketplace between supply side (application providers) and demand side (customers). Cloud service providers have to validate applications to be included in their service portfolio. Not only performance, security, networking, compliances should be checked but also business contract, authentication should be provided. Organization customers are more sensitive to these validation criteria and process. We study the Internet2 NET+, which is a successful cloud marketplace of applications for research and education organizations. This case study shows us three things : (i) a cloud marketplace's application management process : selection, validation, transition to service, customization of applications (ii) what a cloud marketplace has for its infrastructure like authentication, security, access control etc. (iii) what a cloud marketplace has as its governance structure. This case study will provide informative analysis of Internet2 NET, a profit-making vertical and buyer's marketplace (education industry). And we will get some strategic implications for planning and implementing cloud marketplaces.

• Economic and Environmental Geology
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• v.46 no.4
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• pp.313-327
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• 2013

In the study, three-dimensional geostatistical simulations on McMurray Formation which is the largest oil sand reservoir in Athabasca area, Canada were performed, and the optimal site for steam assisted gravity drainage (SAGD) was selected based on the predictions. In the selection, the factors related to the vertical extendibility of steam chamber were considered as the criteria for an optimal site. For the predictions, 110 borehole data acquired from the study area were analyzed in the Markovian transition probability (TP) framework and three-dimensional distributions of the composing media were predicted stochastically through an existing TP based geostatistical model. The potential of a specific medium at a position within the prediction domain was estimated from the ensemble probability based on the multiple realizations. From the ensemble map, the cumulative thickness of the permeable media (i.e. Breccia and Sand) was analyzed and the locations with the highest potential for SAGD applications were delineated. As a supportive criterion for an optimal SAGD site, mean vertical extension of a unit permeable media was also delineated through transition rate based computations. The mean vertical extension of a permeable media show rough agreement with the cumulative thickness in their general distribution. However, the distributions show distinctive disagreement at a few locations where the cumulative thickness was higher due to highly alternating juxtaposition of the permeable and the less permeable media. This observation implies that the cumulative thickness alone may not be a sufficient criterion for an optimal SAGD site and the mean vertical extension of the permeable media needs to be jointly considered for the sound selections.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.2
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• pp.102-117
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• 1999

Vertical distribution of squids in relation to oceanographic structure was analyzed on the basis of experimental squid hand jigging fishing by R/V Pusan 851 in the area of 34°∼47° N, 150° E∼170°W in the North Pacific in summer from 1987 through 1993 with exception of 1991. The 6 species of squids showed different patterns of vertical and horizontal distribution as following; Boreopacific gonate squid (Gonatopsis borealis) were mainly caught in the layer of 71-80m fishing depth of the Subarctic Domain with water temperature of 6∼11℃ and salinity of 32.2∼33.6‰ and distributed in the latitudes of 41°∼43° N. Boreal clubhook squid (Onychoteuthis borealijaponica) were mainly caught in the layer of 11∼20m fishing depth of the Subarctic Domain with water temperature of 10∼12℃ and salinity of 32.9∼33.6‰ and distributed in the latitudes of 41°∼42N°. Tapanese flying squid (Todarodes pacificus) were mainly caught in the layer of 11∼20m fishing depth of the Transition Zone and the Subtropical Domain with water temperature of 15∼18℃ and salinity of 33.6∼34.0‰ and distributed in the latitudes of 40°∼42°N. Neon flying squid (Ommastrephes bartrami) were mainly caught in the layer of surface∼10m fishing depth of the Subarctic Convergence Zone and the Transition Zone with water temperature of 16∼17℃ and salinity of 33.7∼34.4‰ and distributed in the latitudes of 39 °∼41°N. Luminous flying squid (Symplectoteuthis luminosa) were mainly caught in the layer of 11 20m fishing depth of the Transition Zone and the Subtropical Domain with water temperature of 18∼20℃ and salinity of 33.8∼34.6‰ and distributed in the latitudes of 37°∼39°N. Purpleback flying squid (Symplectoteuthis oualaniensis) were mainly caught in the layer of surface∼10m fishing depth of the Subtropical Domain with water temperature of 24∼25℃ and salinity of 34.2∼34.4‰ and distributed in the latitude of 36°∼37°N.