• Wind and Structures
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• v.5 no.2_3_4
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• pp.127-140
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• 2002

This paper presents some of the results of a project whose aim has been to produce a full simulation model which would determine the efficacy of pesticides for use by both farmers and the bio-chemical industry. The work presented here describes how crop architecture can be mathematically modelled and how the mechanics of pesticide droplet capture can be simulated so that if a wind assisted droplet-trajectory model is assumed then droplet deposition patterns on crop surfaces can be predicted. This achievement, when combined with biological response models, will then enable the efficacy of pesticide use to be predicted.

• The Korean Journal of Pain
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• v.27 no.1
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• pp.43-48
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• 2014

Background: This study tests the hypothesis that of bipolar radiofrequency thermocoagulation of the thoracic facet joint capsule may provide a safe and effect method of pain control from thoracic facet origin. Methods: Among patients suffering from localized mid back pain, nine patients with thoracic facet disease confirmed by magnetic resonance image and diagnostic thoracic facet block were enrolled. Bipolar radiofrequency ablation in the inferior aspect of the thoracic facet joint was done. Visual Analog Scale (VAS) was measured pre-intervention and 1 month post-intervention. Any complications and changes in amount of pain medication were recorded. Results: Significant 47.6% reduction in VAS was noted at 1 month. There were no serious complications. Conclusions: Intra-articular bipolar radiofrequency thermocoagulation of the thoracic facet joint may be a technically easier and valid method of treating mid back pain of thoracic facet origin.

• Bulletin of the Korean Mathematical Society
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• v.46 no.5
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• pp.823-833
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• 2009

It is well-known that if a convex hyperbolic polygon is constructed as a fundamental domain for a subgroup of the modular group, then its translates by the group elements form a locally finite tessellation and its side-pairing transformations form a system of generators for the group. Such hyperbolically convex polygons can be obtained by using Dirichlet's and Ford's polygon constructions. Another method of obtaining a fundamental domain for subgroups of the modular group is through the use of a right coset decomposition and we call such domains standard fundamental domains. In this paper we give subgroups of the modular group which do not have hyperbolically convex standard fundamental domain containing only inequivalent cusps.

• Carbon letters
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• v.15 no.3
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• pp.162-170
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• 2014

Pitch is an attractive raw material for carbon fiber precursors due to its low cost stemming from its availability as a residue of coking and petroleum processes. Ford Motor Company reported a carbon fiber target price of $11.0/kg by using a fast cycle-time manufacturing method with carbon fiber in an inexpensive format, allowing for an average retail price of gasoline of $3.58/gallon. They also recommended the use of carbon fiber with strength of 1700 MPa, modulus of 170 GPa, and 1.5% elongation. This study introduced a ca. $5.5{\mu}m$ carbon fiber with 2000 MPa tensile strength obtained from a precursor through simple distillation of petroleum residue. Petroleum pitch based carbon nanofibers prepared via electrospinning were characterized and potential applications were introduced on the basis of their large specific surface area and relatively high electrical conductivity.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1855-1860
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• 2010

Electric vehicles have reached a new level of development with introductions by Chrysler, Ford, Honda and Toyota. Today's charging technology includes conductive and inductive charging systems. There are three standardized charging levels: Level 1: charging can be done from a standard, grounded AC 120V, 3-prong outlet available in all homes; Level 2: charging is at AC 240V, 40 amp charging station with special consumer features to make it easy and convenient to plug in and charge EVs at home or at an EV charging station; Level 3: a high-powered charging "fast charge" technology currently under development that will provide a charge in less than 15 minutes. The incoming AC power is converted to DC and stored in the vehicle's batteries. In this paper, we investigated the application of urban railway DC electric power for electric car charging system.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.2
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• pp.156-161
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• 2012

In case of commercializing of the hydrogen fuel cell vehicle, the suitable emergency response guide is necessary to prepare an accident. In order to suggest the suitable guide for the domestic affairs, the existing external guide about GM, Ford, Honda, and Hyundai was reviewed. The emergency response guides in CAFCP and main FC vehicle makers were included in the analysis. As the results, it was found that the design and make of vehicle for the domestic user are demanded in the emergency response and the guide is made with the shut-down manual picked out for the rescuer and repair man as well as user.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.499-508
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• 2008

Frequency regulation in off-normal conditions has been an important problem in electric power system design/operation and is becoming much more significant today due to the increasing size, changing structure and complexity of interconnected power systems. Increasing economic pressures for power system efficiency and reliability have led to a requirement for maintaining power system frequency closer to nominal value. This paper presents a decentralized frequency control framework using a modified low-order frequency response model containing a proportional-integral(PI) controller. The proposed framework is suitable for near-normal and emergency operating conditions. An $H_{\infty}$ control technique is applied to achieve optimal PI parameters, and an analytic approach is used to analyse the system frequency response for wide area operating conditions. Time-domain simulations with a multi-area power system example show that the simulated results agree with those predicted analytically.

• IE interfaces
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• v.4 no.2
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• pp.25-34
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• 1991

The problem of scheduling the passage things with low transit priority to maximize the amonnt that can be sent during given time periods without interfering with the fixed schedule for passage things with high transit priority in a track, is treated in this paper. The problem is transformed into the Time Expanded Network without traverse time through the Ford and Fulkerson Model and the Enumeration Algorithm is developed for solutions using TENET GENerator(TENETGEN). Finally, the proposed algorithm is compared with Dinic's maximal-flow algorithm and examined for the availability of the procedures on the personal computer.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.224-229
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• 2000

This paper describe a (mite element computer simulation of a absorption system using full scale car crash test. The full scale test selected for this study is a 80kmh frontal, side and 25% offset impact of a 1993 Ford Taurus vehicle into a absorption system. This absorption system has external rubber and internal steel pannel. This simulation has completed for decision of these components energy absorption performance. Dynamical performance of this system and movement are obtained from this simulation. and then We can appreciate the safety of passenger from measure the vehicle C.G's acceleration.

• 한국컴퓨터산업교육학회:학술대회논문집
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• 2003.11a
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• pp.87-94
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• 2003

Anisotropic diffusion is a selective smoothing technique that promotes smoothing within a region instead of smoothing across boundaries. In anisotropic diffusion, the rate of smoothing is controlled by the local value of the diffusion coefficient chosen to be a function of the local image gradient magnitude. El-Fallah and Gary E. Ford represented the image as a surface and proved that setting the inhomogeneous diffusion coefficient equal to the inverse of the magnitude of the surface normal results in surface evolving speed that is proportional to the mean curvature of the image surface. This model has the advantage of having the mean curvature diffusion (MCD) render invariant magnitude, thereby preserving structure and locality. In this paper, the proposed MCD model efficiently reduces diffusion coefficient at the thin edges using the smoothness of the surface.