• Composites Research
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• v.15 no.1
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• pp.1-8
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• 2002

In this study, the flutter analysis for a rectangular box wing and an actual fighter wing with composite shin, aluminum spar and aluminum rib has been conducted. A conservative 3D wing-box model of an actual wing is modeled by MSC/PATRAN and the corresponding free vibration analysis has been performed by MSC/NASTRAN. The finite elements of membrane, rod and shear panel are used. Using the practical ply angles, various composite laminates are composed and analysed. The DLM code which is linear aerodynamic theory in frequency domain is applied to calculate unsteady aerodynamic pressure in subsonic flow region and the V-g and p-k methods are applied to obtain the solution of aeroelastic governing equation in frequency domain.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.941-946
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• 2006

It followed in system development and SMRT(Seoul Metropolitan Rapid Transit Co)System reached to an automatic train operation(ATO) and driverless operation(DLM) from the manual operation due to the train driver. The train like the general bus or the car vehicle was not serial riding in a car and the Parallel concept which the numerous passenger rides in a car simultaneously occur frequently the charge of the train driver unmanned bitterly from existing manual handling was a possibility of doing, train open door control(ODM) which bites also ATO, it handles it minimized. Like this ATO/DLM, the control system which bites being a Wayside to Train communication for immediacy, it is a system of the Vital concept the immediacy of the citizen Data evil the radio information transmission and the train of the interface which is accurate from unmanned operation and, will decipher, will accomplish it will guarantee. It respects the passenger accident prevention and an air question environment improvement from subway platform and phul leys the screen door of Platform(PSD) with the fire tube frost it refers and part it treats and to sleep it does, ODM which bites is accuracy and immediacy of altitude and when seeing from the viewpoint which demands the trust of altitude, ODM system the trust of car incest interface in the equipment construction which is safe and the comparative analysis back of the system analysis against the control which bites and case study and other subway system it leads from the research which it sees and signal - train in base grudge to sleep it contributes it does.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.48-52
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• 1993

To furnish basic data for the utilization of leaf mustard as a raw material of salted and fermented vegetable food, major chemical compositions of Dolsan Leaf Mustard (DLM) were investigated. The moisture and ash contents of DLM were 87.5% and 1.4%, respectively. Compared with other Korean traditional or Japanese leaf mustard, DIM contained more crude protein (3.8%) but less crude fat (0.3%) and crude fiber (1.3%). As an alkali food, leaf and leat stalk had pH of 5.7 and 5.8, titratable acidity of 687 and 318mg/100g and alkalinity of 2.5 and 5.2, respectively. The major free sugar in DLM was glucose and fructose was also detected in a small amount. The contents of total and reducing sugar in leaf and leaf stalk were 574, 352, 820 and 538mg%, respectively. Total amino acid contents of leaf and leaf stalk were 8.0 and 2.5% on wet basis. Although the amino acid compositions of leaf and leaf stalk were different each other, glutamic acid and proline were the major amino acids in both of the leaf and leaf stalk. Significantly higher amount (ca.10.3-fold) of free amino acid was present in leaf (3074mg%) than in leaf stalk (298mg%). Glutamic acid and aspartic acid were the major free amino acids and essential amino acid contents in leaf and leaf stalk were 869 and 68mg% being 22.9 and 28.3% of total free amino acids.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.867-878
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• 2018

As the era of AVs (Automated Vehicles) comes to a close, many researches related to AVs have been conducted. Up until now, research on traffic flow impact of AVs has been the main topic, and research on traffic management for AVs is still in beginning stage. This study analyzed the effect of Dynamic Merge Control (DMC) in manual vehicle (MV) and AV environment at work zone. Dynamic Late Merge (DLM) and DLM with Dynamic Early Merge (DEM) are compared by simulation. Simulation results showed that DLM improves travel time and work zone throughput compared to no merge control case in both MV and AV environment. In the case of additional operation of DEM, the improvement effect was not observed in MV environment, but it was improved in AV environment. As a result, DMC operation in AV environment was as effective as the improvement in transition from MV to AV environment. Therefore congestion reduction at freeway work zone by DMC will be possible in future AV environment, and the improvement of DMC can be suggested.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.632-634
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• 1999

기존의 화상전화 시스템 및 화상회의 시스템은 H/W로 구현된 H.263 CODEC을 사용한 경우는 있었지만, 컴퓨터의 성능변수와 직접적인 관계가 있는 S/W CODEC을 사용한 경우는 드물었다. 여기에 착안하여 본 연구는 PSTN 망에서의 화상회의 및 화상전화에 응용할 수 있는 실시간 H.263 S/W CODEC을 구현하였다. H.263 S/W CODEC을 MuX(Multimedia I/O Server)의 DLM으로 구현함으로써 현재 LAN 기반으로 동작하는 MuX를 PSTN망으로 확장하는데 있어 기반 기술로 사용할 수 있으며, 대역폭이 낮은 LAN 환경에서도 안정적인 화상회의가 가능하도록 하였다.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.29-33
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• 2020

Despite the same system architecture and operation principle, Advanced Metering Infrastructure (AMI) and Internet of Things (IoT) are recognized as a heterogeneous system. This is due to the different object modeling and communication protocols used in smart meters and sensors. However, data interworking between AMI and IoT is expected to be inevitable in the future. In this paper, we propose Device Language Message Specification (DLMS) to Lightweight Machine to Machine (LwM2M) conversion model. The proposed interworking model can reduce the packet size by 46.5% compared to that of the encapsulation method.

• Korean Journal of Metals and Materials
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• v.50 no.2
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• pp.107-115
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• 2012

Direct laser melting (DLM) is a powder-based additive manufacturing process to produce parts by layer-by-layer laser melting. As the properties of the manufactured parts depend strongly on the deposited laser-melted bead, deposited layers obtained by the DLM process were characterized in this study. This investigation used a 200 W fiber laser to produce single-line beads under a variety of different energy distributions. In order to obtain a feasible range for the two main process parameters (i.e. laser power and scan rate), bead shapes of single track deposition were intensively investigated. The effects of the processing parameters, such as powder layer thickness and scan spacing, on geometries of the deposited layers have also been analyzed. As a result, minimum energy criteria that can achieve a complete melting have been suggested at the given powder layer thickness. The surface roughnesses of the deposited beads were strongly dependent on the overlap ratio of adjacent beads and on the energy distributions of laser power. Through microstructural analysis and hardness measurement, the morphological and mechanical properties of the deposited layers at various overlapped beads have also been characterized.

• Transactions of Materials Processing
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• v.28 no.1
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• pp.21-26
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• 2019

Direct Laser Melting (DLM) of $Ti-xTiH_2$ (mixing ratio x = 2, 5, 10 wt.%) blended powder is characterized by producing porous titanium parts. When a high energy laser is irradiated on a $Ti-TiH_2$ blended powder, hydrogen gas ($H_2$) is produced by the accompanying decomposition of the $TiH_2$ powder, and acts as a pore-forming and activator. The hydrogen gas trapped in a rapidly solidified molten pool, which generates porosity in the deposited layer. In this study, the effects of a $TiH_2$ mixing ratio and the associated processing parameters on the development of a porous titanium were investigated. It was determined that as the content of $TiH_2$ increases, the resulting porosity density also increases, due to the increase of $H_2$ produced by $TiH_2$. Also, porosity increases as the scan speed increases. As fast solidified melting pools do not provide enough time for $H_2$ to escape, the faster the scan speed, the more the resulting $H_2$ is captured by the process. The results of this study show that the mixing ratio (x) and laser machining parameters can be adjusted to actively generate and control the porosity of the DLM parts.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.10
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• pp.141-151
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• 1994

this paper describes the design and implementation of a RISC processor for embedded control systems. This RISC processor integrates a register file, a pipelined execution unit, a FPU interface, a memory interface, and an instruction prefetcher. Its characteristics include both single cycle executions of most instructions in a 2 phase 20 MHz frequency and the worst case interrupt latency of 7 cycles with the vectored interrupt handling that makes it possible to be applicable to the real time processing system. For efficient handling of multi-cycle instructions, data stationary hardwired control scheme equippedwith cycle counter was used. This chip integrates about 139K transistors and occupies 9.1mm$\times$9.1mm in a 1.0um DLM CMOS technology. The power dissipation is 0.8 Watts from a 5V supply at 20 MHz operation.

• The Mathematical Education
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• v.31 no.2
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• pp.121-132
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• 1992

The pointwise convergence define the relation-ship between the mesh-size and the tolerance. This will play an important role in improving quality of finite element approximate solution. In this paper, We evaluate the convergence on a certaon unknown point with a 1-irregular mesh refinement. This m that the degree of freedom is minimized within a tolerance.