• 한국전산유체공학회:학술대회논문집
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• 2004.03a
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• pp.119-125
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• 2004

Unsteady nonlinear wave motions on the free surface over a plane beach of constant slope are numerically simulated using a finite difference method in rectangular grid system. Two-dimensional Navier-Stokes equations and the continuity equation are used for the computations. Irregular leg lengths and stars are employed near the boundaries of body and free surface to satisfy the boundary conditions. Also, the free surface which consists of markers or segments is determined every time step with the satisfaction of kinematic and dynamic free surface conditions. Moreover, marker-density method is also adopted to allow plunging jets impinging on the free surface. The second-order Stokes wave theory and solitary wave theory are employed for the generation of waves on the inflow boundary. For the simulation of wave breaking phenomena, the computations are carried out with the plane beach of constant slope in surf zone. The results are compared with each other. The marker-density method is better then the hybrid method. Also they are compared with other existing experimental results. The Agreement between the experimental data and the computation results is good.

• International Journal of Automotive Technology
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• v.8 no.6
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• pp.723-730
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• 2007

The typical design of automotive driveshafts generally utilizes Constant Velocity(CV) joints as a solution to NVH. CV joints are an integral part of vehicles and significantly affect steering, suspension, and vehicle vibration comfort levels. Thus, CV joints have been favored over universal joints due to the constant velocity torque transfer and plunging capability. Although CV joints are common in vehicle applications, current research works on modeling CV joint friction and assumes constant empirical friction coefficient values. However, such models are long known to be inaccurate, especially under dynamic conditions, which is the case for CV joints. In this paper, an instrumented advanced CV joint friction apparatus was developed to measure the internal friction behavior of CV joints using actual tripod-type joint assemblies. The setup is capable of measuring key performance of friction under different realistic operating conditions of oscillatory speeds, torque and joint installation angles. The apparatus incorporates a custom-installed triaxial force sensor inside of the joint to measure the internal CV joint forces(including friction). Using the designed test setup, the intrinsic interfacial parameters of CV joints were investigated in order to understand their contact and friction mechanisms. The results provide a better understanding of CV joint friction characteristics in developing improved automotive driveshafts.

• Journal of IKEEE
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• v.18 no.1
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• pp.106-113
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• 2014

A pedestrian detector can be applied for various purposes such as monitoring or counting the number of people in some place, or detecting the people plunging in the driveway. There was a lot of related research. But, the detection speed is slow in embedded system because of the limited computing power. An algorithm for fast pedestrian detector using HOG in ARM SIMD architecture is presented in this paper. There is a way to quickly remove the background of image and to improve the detection speed using NEON parallel technique. When we tested with INRIA Person Dataset, the proposed pedestrian detector improves the speed by 3.01 times than previous one.

• Lingua Humanitatis
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• v.8
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• pp.223-239
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• 2006

This paper centers around the etymological meanings of place names of the Kumkang region, restricting the discussion to a selected group of place names which make it possible to infer their cultural characteristics in the light of the latitudinal or longitudinal isoglosses. The legends of Komnaru and Choryongdae, for instance, derive directly from place names. Dialectal distribution is examined on the basis of the phonological features that are not very different between upper and lower reaches of the Kumkang river. The dialects get much more similar as they go further down to the lower region of the river. The original "Komanara(熊津)", also called "Northern Headland(北津)", underwent the sound change of Komannaru > Komkang > Kumkang(錦江), the last being alternatively abbreviated as Kum(錦). During the last half of the 14th century-around the close of the Koryo dynasty, that is-a literary work gave the beautified name "Nakhwa-am"(落花巖), meaning 'rock-bluff of falling flowers', to what was originally called Tasa-am(墮死岩), so-called because, in the year of 660 when the Paekje dynasty was being ravaged by the invading enemy, a number of court-ladies ended their lives by plunging into the river from there. It was 'a number of court-ladies'(諸後宮) who died; but by tradition of popular songs, the number has become "three thousand" - a case of hyperbole of course.

• Journal of the Korea Society of Computer and Information
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• v.3 no.2
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• pp.209-216
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• 1998

The Korean economy has been under the IMF-led rescue programs since the late 1997. For the transparency of financial currency, Korean government had made the Korean firms which are depend on each other financially compose the consolidated financial statements since 1985, because South Korea's financial crisis has been caused by a string of corporate failures that have put enormous strain on the banking system at a time when the won was plunging against the dollar. But there are many problems to get the transparency in the actions and accountability of both public and private institutions, because of the domestic corporations' structural characteristics and the law of accounting. This paper reviewed, therefore, some problems on the consolidated financial statements and advantages to introducing the combined financial statements through comparing the contents of those statements

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.7-17
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• 2002

Recently, artificial rocks, instead of buoys, have been placed on the submerged breakwater to indicate its location. The accurate estimation of wave forces on these rocks is deemed necessary for their stability design. Characteristics of the wave force, however, are expected . to be very complicated because of the occurrence of breaking or post-breaking waves. In this regard, wave forces exerted on an artificial rock have been investigated in this paper. The maximum wave force has been found to strongly dependent on the location and shape of the artificial rock that is placed on the submerged breakwater. The plunging breaker occurs near the loading cram edge of a submerged breakwater, which cause impulsive breaking wave force on the rock. Using the Morison equation, with the velocity and acceleration at the front face of the artificial rock and varying water surface level, it is possible to estimate wave forces, even impulsive breaking wave forces, that are acting on the rock installed on a submerged breakwater. The vertical wave force is also found to depend, significantly, on the buoyant force.

• Journal of Ship and Ocean Technology
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• v.8 no.2
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• pp.61-69
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• 2004

Unsteady nonlinear wave motions on the free surface over a plane beach of constant slope are numerically simulated using a finite difference method in rectangular grid system. Two-dimensional Navier-Stokes equations and the continuity equation are used for the computations. Irregular leg lengths and stars are employed near the boundaries of body and free surface to satisfy the boundary conditions. Also, the free surface which consists of markers or segments is determined every time step with the satisfaction of kinematic and dynamic free surface conditions. Moreover, marker-density method is also adopted to allow plunging jets impinging on the free surface. The second-order Stokes wave theory is employed for the generation of waves on the inflow boundary. For the simulation of wave breaking phenomena, the computations are carried out with the plane beach of constant slope in surf zone. The results are compared with other existing experimental results. Agreement between the experimental data and the computation results is good.

• Asian Oncology Nursing
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• v.8 no.2
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• pp.111-119
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• 2008

Purpose: The purpose of this study was to describe the experience of hospice nurses on spiritual care. Methods: Data was collected from 9 hospice nurses by using in-depth interview. The main questions include what they understand as spiritual care, when they feel the needs of spiritual care, how they perform spiritual care, and what is the outcome of spiritual care. The data was analyzed by grounded theory methodology developed by Strauss and Corbin. Results: The core category of experience of hospice nurses on spiritual care was identified as "Untie a knot of mind". In the process of spiritual care in hospice nurses was consisted of soothing, dwelling with, releasing, giving meaning, plunging, and going beyond a life. Conclusion: The result of this study was expected to give useful information to nurses and nursing managers about the real situation of performance of spiritual care. The findings of this study contributes to developing programs and supportive policies for encouraging spiritual care.

• Water for future
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• v.27 no.2
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• pp.63-72
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• 1994

In this study, hydraulic characteristics for upstream migration of fish in a pool-and-weir fishway were analyzed through experiment. The results showed that streaming flow was preferable to plunging flow for upstream migration of fish and it was not good to make an orifice beneath the septum since it generates turbulent jet and eddies. Protrusions on the side wall of fishway were preferable to grooves since they decelerate flow velocity and make upstream migration easy. A vertically movable septum was necessary for a flushing of deposited bed material, and net installing over fishway was also needed for birds not to approach the fishway and eat fish.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.3
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• pp.14-21
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• 2006

The unsteady vortex lattice method is used to model twisting and flapping motions of a rectangular flat plate wing. The results for plunging and pitching motions were compared with the limited experimental results available and other numerical methods. They show that the method is capable of simulating many of the features of complex flapping flight. The lift, thrust and propulsive efficiency of a rectangular flat plate wing have been calculated for various twisting angles and reduced frequency with an amplitude of flapping angle($20^{\circ}$). And the effects of the twisting on the aerodynamic characteristics of the flapping wing are discussed by examination of their trends.