• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.11
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• pp.973-980
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• 2016

An air traffic management (ATM) has been studied in a variety of fields to utilize an air traffic capacity efficiently and solve a congested air traffic situation due to an increment of an air traffic demand. In this paper, an air traffic management, which is related with controlling and determining the sequencing of an aircraft approaching to an airport, in terminal control area is studied. This paper focuses on scheduling algorithms with a given problem for the air traffic management with operational constraints, such as a space separation, an overtaking on the same air-route, and a route merge point (a scheduling point). For a real-time calculation, the presented algorithms focus on dispatching heuristic rules which are able to assign tasks in a fast time period with an adequate performance, which can be demonstrated as a proper and realistic scheduling algorithm. A simulation result is presented to illustrate the validity and applicability of the proposed algorithm. Each scheduling rule is analyzed on the same static and dynamic air traffic flow scenario with the ATM Monte-Carlo simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.720-725
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• 2017

This paper evaluated the safety and serviceability of a building structure considering the multi-hazard and proposed TMD-based adaptive smart control system to improve the structural performance. To make multi-hazard loads, an artificial earthquake and artificial wind loads were generated based on representative regions of strong seismicity and strong wind in U.S.A. The safety and serviceability of a 20-story example building structure were investigated using the generated artificial loads. A smart TMD was employed to improve the safety and serviceability of the example structure and its capacity of structural performance improvement was evaluated. The smart TMD was comprised of a MR (magnetorheological) damper. Numerical analysis showed that the example building structure could not satisfy the design limit of safety and serviceability with respect to multi-hazard. The smart TMD effectively reduced the seismic responses associated with the safety and wind-induce responses associated with serviceability.

• Earthquakes and Structures
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• v.12 no.1
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• pp.13-21
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• 2017

Recent seismic events occurred in Italy (Emilia-Romagna 2012, Abruzzo 2009) and worldwide (New Zealand 2010 and 2011) highlighted some of the weaknesses of precast concrete industrial buildings, especially those related to the connecting systems traditionally employed to fasten the cladding panels to the internal framing. In fact, one of the most commons fails it is possible to observe in such structural typologies is related to the out-of-plane collapse of the external walls due to the unsatisfactory behaviour of the connectors used to join the panels to the perimeter beams. In this work, the strengthening of a traditional industrial building, assumed as a case study, made by precast reinforced concrete is proposed by the adoption of a dual system allowing the reinforcement of the structure by acting both internally; by pendular columns and, externally, on the walls. In particular, traditional connections at the top of the walls are substituted by devices able to work as a slider with vertical axis while, the bottom of the walls is equipped with two or more hysteretic dampers working on the uplift of the cladding panels occurring under seismic actions. By means of this approach, the structure is stiffened; obtaining a reduction of the lateral drifts under serviceability limit states. In addition, its seismic behaviour is improved due to the additional source of energy dissipation represented by the dampers located at the base of the walls. The effectiveness of the suggested retrofitting approach has been checked by comparing the performance of the retrofitted structure with those of the structure unreinforced by means of both pushover and Incremental Dynamic Analyses (IDA) in terms of behaviour factor, assumed as a measure of the ductility capacity of the structure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.5B
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• pp.771-776
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• 2010

In this paper, we present an efficient centralized dynamic bandwidth allocation scheme with multicasting for asymmetric 10G-Ethernet Passive Optical Networks (10G-EPONs). The proposed scheme is based on multicast-burst polling and provides quality of service (QoS) with class of service (CoS) to different lasses of packets. It is shown that a well-known conventional interleaved polling scheme severely decreases downstream channel capacity for user traffic when the upstream network load is low (avalanche gate frequency). To overcome this problem, we have proposed a multicast burst polling scheme which shows impressively lower downstream bandwidth consumption compare to IPACT and moreover it did not show the light load penalty problem. Simulation results using an OPNET tool show that the multicast burst polling effectively eliminates light-load penalty and minimizes downstream bandwidth consumption under avalanche gate frequencies.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.1-8
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• 1999

Dynamic elastoplastic LPM (lumped parameter mass) analyses are carried out in order to investigate the seismic resistant performance of a typical high-rise shear wall apartment subjected to several earthquakes. Three-dimensional nonlinear pushover analysis is adopted to estimate initial elastic stiffness, yielding strength and post-yielding stiffness of each story for the time history analysis of LPM shear model. For the hysteresis of each story, Clough and bilinear models are used with the input of four recorded earthquake ground motions of EI Centro 1940 NS, Taft 1952 EW, Hachinohe 1968 NS and Kobe 1995 NS, of which the amplitudes are scaled down to have the same maximum ground velocity of 12 kine. The result shows that yieldings take place in most storys of the building, i.e. the earthquake resistant capacity of this high-rise shear wall apartment is not sufficient at the event of earthquake M=5~6.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.3
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• pp.223-230
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• 2017

BIM(building information modeling) has been actively applied to construction industries and to maximize its application through the life cycle of structure, various relevant technologies have been proposed. In particular, 4D sequencing management and 5D cost-related management were introduced as an improved version of the design review and interface control by 3D information design. On the other hand, the virtual construction using virtual construction equipment can sophisticatedly handle capacity, dynamic movement, collision boundaries of actual construction machines but it still stays at a low level in a technical sense. In this study, simulation systems based on BIM involving virtual construction equipment have been developed; then it is applied to the actual construction project to evaluate the safety and efficiency of construction equipments. It was confirmed that the simulation systems can be utilized to construct virtual construction site by using an effective 3D library of construction equipment and can plays a key role to secure construction safety and economic feasibility. Specifically, the simulation system are very useful for decision making by construction managers to select the optimum equipment and construction method with a better understanding for safety and cost-saving.

• Journal of Korea Game Society
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• v.9 no.5
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• pp.137-144
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• 2009

This paper predicts 6 facial regions that may have sharply different scattering properties, rendering the face more realistically based on their diffusion profiles. The scattering properties are acquired in the form of high dynamic range by photographing the pattern formed around an unit ray incident on facial skin. The acquired data are fitted to a 'linear combination of Gaussian functions', which well approximates the original diffusion profile of skin and has good characteristics as the filter. During the process, to prevent its solutions from converging into local minima, we take advantage of the genetic algorithm to set up the initial value. Each Gaussian term is applied to the irradiance map as a filter, expressing subsurface scattering effect. In this paper, to efficiently handle the maximum 12 Gaussian filterings, we make use of the parallel capacity of CUDA.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.28-35
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• 2004

Driven pile has the excellent bearing characteristics and good economics, so it is known as the comparative piling method. To use the advantages of driven pile fully, it is necessary to perform the proper construction management. Engineers must drive pile to the proper bearing layer with proper blow energy and measure the blow count and penetration per certain depth to analyze the bearing capacity and driveability. In conventional method, these parameters have been measured manually so it was difficult to get good accuracy. After PIR-D(Pile Installation Recorder-Driven Pile) was attached to the driving equipment, the hammer efficiency, blow count and penetration in blow/10cm were measured automatically. In this paper, to givethe rational judgement criteria of bearing layer, driveability, blow/10cm according to pile depth during pile driving, the some relationship between the driving resistance and ground layer distribution was analyzed. The ground investigation during piles (PHC ${\Phi}450,\;{\Phi}400\;&\;Steel\;Pile\;{\Phi}609{\ast}16t$) installation in the marine clay layer in Incheon, the sandy soil layer in Yongin and the tuff layer in Pusan was done. And measuring hammer efficiency not doing recently, we could compare hammer efficiency(Eh) by PIR-D and energy transfer ratio(ETR) by Pile Dynamic Analyzer(PDA).

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.262-267
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• 2006

The objective of this study was to develop new self-organized nanogels as a means of drug delivery in patients with cancer. Pullulan (PUL) and deoxycholic acid (DOCA) were conjugated through an ester linkage between the hydroxyl group in PUL and the carboxyl group in DOCA. Three types of PUL/DOCA conjugates were obtained, differing in the number of DOCA substitutions (DS; 5, 8, or 11) per 100 PUL anhydroglucose units. The physicochemical properties of the resulting nanogels were characterized by dynamic light scattering, transmission electron microscopy, and fluorescence spectroscopy. The mean diameter of DS 11 was the smallest (approx. 100 nm), and the size distribution was unimodal. To determine the organizing behavior of these conjugates, we calculated their critical aggregation concentrations (CACs) in a 0.01-M phosphate buffered saline solution. They were $10.5{\times}10^{-4}mg/mL,\;7.2{\times}10^{-4} mg/mL,\;and\;5.6{\times}10^{-4} mg/mL$ for DS 5, 8, and 11, respectively. This indicates that DOCA can serve as a hydrophobic moiety to create self-organized nanogels. To monitor the drug-releasing behavior of these nanogels, we loaded doxorubicin (DOX) onto the conjugates. The DOX-loading efficiency increased with the degree of DOCA substitution. The release rates of DOX from PUL/DOCA nanogels varied inversely with the DS. We concluded that the PUL/DOCA nanogel has some potential for use as an anticancer drug carrier because of its low CAC and satisfactory drug-loading capacity.

• The Korean Journal of Ceramics
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• v.5 no.3
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• pp.296-302
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• 1999

The state of the art of the 2-stage swirl calciner is to make 2-stage counter gas flow in a calciner with cooler hot air. Gas flow in the calciner increases retention time of raw mix particles. Simple structure of the 2-stage swirl calciner operated optimally the rotary cement kiln. In this study, in order to decide the entrance type of the cooler air of the optimal calciner model, an entrance cooler air velocity, the input points of raw mix were analyzed in many aspects with cold model experiment and computational fluidized dynamic simulation. It was found that the entrance type of cooler air fully splite 2-stage for the optimal condition of the cold model calciner. The operation conditions were that the input feeding, the cooler air velocity and the air velocity of throat were 0.33kg/$\textrm m$3$, 15m/s and 20m/s respectively. The performance of 150 t/d the pilot plant connected with the kiln rising duct was that volume capacity of the calciner is over 430 kg/$\textrm m$3$-h, decarbonation rate of raw mix apparently 90%, heat consumption 950 kcal/kg-cli and retention time of raw mix 2.4 sec. Its the best operating condition is cooler air velocity 18m/s, the gas velocity of throat 25m/s, feeding rate of raw mix 10t/h. The operating experience of the pilot plant confirmed the success of scale up for over 3000 t-cli/d.