• Journal of Environmental Science International
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• v.13 no.10
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• pp.891-902
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• 2004

In order to predict air pollution and Yellow-sand dispersion precisely, it is necessary to clarify the sensitivity of meteorological field input interval. Therefore numerical experiment by atmospheric dynamic model(RAMS) and atmospheric dispersion model(PDAS) was performed for evaluating the effect of temporal and spatial resolution of meteorological data on particle dispersion. The results are as follows: 1) Base on the result of RAMS simulation, surface wind direction and speed can either synchronize upper wind or not. If surface wind and upper wind do not synchronize, precise prediction of Yellow-sand dispersion is strongly associated with upwelling process of sand of particle. 2) There is no significant discrepance in distribution of particle under usage of difference temporal resolution of meteorological information at early time of simulation, but the difference of distribution of particles become large as time goes by. 3) There is little difference between calculated particles distributions in dispersion experiments with high temporal resolution of meteorological data. On the other hand, low resolution of meteorological data occur the quantitative difference of particle density and there is strong tendency to the quantitative difference.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.158-164
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• 2008

This study was conducted for raising the considering the dynamical context of mobile phone use environment in the mobile-phone research. For this I identified the characteristic of the mobile phone use. The first characteristic is that the mobile phone is the context sensitive device. Also, it reflects the user's life pattern because it is the very personal device. I defined the context of mobile phone use with the basis on this identification of those characteristics. I referenced the definition, 'situational context', defining the mobile phone use context. Also, I set up the research scope within the user task that is influential from the situational context, I named this kind of task as the 'contextual task'. I developed the Contextual Task Model in this study. I named the model as the 'ESR Model'. The reason that I developed this contextual task model is that this model can help novice designers and designers unfamiliar with an application domain understand the user behavior and user centered design. And also this model can be effective to communicate each other, I identified the user's contextual tasks three kinds of model. First, the Extend Model includes user tasks that related to extending from user physical working space to the virtual level. Second model is Synchronize Model, which includes issues that lesson the blocking when use several functions at a time or sequentially. Third model is Replace Model, which is come from the characteristic of user life pattern to use the mobile phone. Finally, I proposed an application of this model, CIQ. Through the process to make CIQ I proved the effectiveness of this ESR Model.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.155-158
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• 2000

In this paper, we propose a Windows-based presentation system using laser pointer mouse. Major-characteristics of this system is to synchronize the laser pointing position with the PC cursor such that the laser can function as not only pointer, but also a PC mouse. It is shown that we use a special pattern to coincide the coordinate of the camera capture image with that of the pc window. We finally show its feasibility by some experiments with the implemented system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.661-664
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• 2006

Under a VMI (Vendor Managed Inventory) system, the vendor holds a certain level of control over not only inbound replenishment decisions on stocking but also outbound re-supply decisions. In this situation, vendor faces a better opportunity to synchronize the inventory and transportation decisions. However, shipment consolidation can reduce transportation expenses, but delivery time about the customer comes to be long and a customer service is fallen. Thus, a stock and transportation decision must consider this correlation. This study look into the relevant literature and suggest about further research direction.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.955-957
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• 1998

Switched reluctance motor(SRM) has the advantages of simple structure, low rotor inertia, and high poer rate per unit volume. However, position sensor isessential in SRM in order to synchronize the phase excitation to the rotor position. The position sensors increase the cost of drive system, and tend to reduce system reliability. This paper investigtes the speed control of sensorless SRM. The proposed system consists of position detection circuit, dwell angle controller, digital logic commutator, PI speed controller and 4-phase inverter. The performances in the proposed system are verified through the experiment.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.33.3-33
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• 2002

Pseudolite (PL) is a kind of signal generator, which transmits GPS-like signal at the ground. However our own made PL is different from a GPS satellite in clock accuracy. GPS satellites are synchronized by use of high precision atomic clocks. But because our PLs use low cost temperature controlled oscillators (TCXO), so it is very difficult to synchronize them. Hence, we should install reference station and use Differential GPS (DGPS) algorithm to calculate user position. By use of this method, we already developed indoor navigation system a few years ago. We named it as 'Asynchronous Pseudolite Indoor Navigation System'. However, this system requires that sampling times of all the receivers...

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.211-215
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• 1989

This paper describes a dynamic robotic assembly system in which an industrial robot executes peg-in-hole task in a moving state. As an effective means to synchronize the end-effector of the robot with the moving conveyor this work uses a control algorithm which is essentially a PID position control scheme combined with velocity feedforward loop. A RCC wrist is used for the inserting task and its force responses are investigated for various tracking conditions and inserting velocities through a series of experiments.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.83-86
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• 2000

This paper describes a delay-locked loop(DLL_) with low-jitter using Vernier Method. This DLL can be used to synchronize the internal clock to the external clock with very short time interval and fast lock-on. The proposed circuit was simulated in a 0.25 $\mu\textrm{m}$ CMOS technology to realize low-jitter. We verified 50-ps of time interval within 5 clock cycles of the clock as the simulation results.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.117-120
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• 1999

Input queueing is useful for high bandwidth switches and routers because of lower complexity and fewer circuits than output queueing. The input queueing switch, however, suffers HOL-Blocking, which limits the throughput to 58%. To get around this low throughput, we propose a simple scheduling algorithm called Synchronous Input Port (SIP). This method synchronize packets and switching without blocking, which is shown to have better performance over the established algorithms

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.222-224
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• 2000

This Paper investigates the speed control of Switched reluctance motor(SRM) using one chip microcomputer The SRM has the advantages of simple structure low rotor inertia. and high efficiency. The Position sensor is essential in SRM in order to synchronize the Phase excitation to the rotor position. The proposed system consists of phase locked loop controller, switching angle controller and inverter. The Performances in the Proposed system are verified through the experiment.