• Title/Summary/Keyword: Free Flow

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Free Cash Flow, Agency Conflicts, and Compensation Plans in a Non-growing Industry

  • Park, Sang-Bum
    • The Korean Journal of Financial Studies
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    • v.10 no.1
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    • pp.249-269
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    • 2004
  • Free cash flow is known as a typical type of agency conflict between managers and shareholders in a firm. The insurance industry, which is not growing, is particularly susceptible to such excessive cash flow. We herein investigate the effects of stock ownership plans on reducing agency conflicts. We adopt undistributed cash flow to proxy free cash flow, and size, default risk, group membership, leverage, investment opportunity, and stock options are selected as explanatory variables. We find that stock option plans are effective(at a 10% level) in reducing free cash flow.

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TRANSIENT FLOW SIMULATION OF A MIXER WITH FREE SURFACE (자유표면을 고려한 교반기 내부의 비정상 유동해석)

  • Ahn, Ick-Jin;Song, Ae-Kyung;Hur, Nahm-Keon
    • Journal of computational fluids engineering
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    • v.11 no.4 s.35
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    • pp.9-13
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    • 2006
  • In the present study, a numerical analysis of transient mixer flow is performed considering free surface formation. The flow patterns and free surface shape in a mixers formed by flat paddle and pitched paddle impellers are predicted. In a flat paddle mixer, two flow circulation regions are formed due to strong radial flow, whereas one large circulation is formed in a pitched paddle mixer due to axial downward flow. These differences affect the free surface evolution and shape. It is seen from the results that a flat paddle mixer gives deeper free surface at center region than a pitched paddle mixer. The free surface of 8-blades-flat-paddle mixer is also simulated to compare with the available experimental and simulation results. The present computational results agree reasonably well with the experimental data.

Analysis on the free surface flow induced by a pair of source-sink in Stokes flow (스톡스 유동장 내의 한 쌍의 소오스-싱크에 의한 자유표면 유동해석)

  • Jeong, Jae-Tack;Park, Jong-Sun
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.304-307
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    • 2008
  • Two-dimensional Stokes flow due to the line source and line sink of same strength in semi-infinite flow region with free surface is analysed using complex variable theory and conformal mapping. Surface tension effects are included while gravity is neglected. From the results of analysis, flow pattern and free surface shape are obtained and velocity distribution on the free surface is determined with 2 independent parameters Ca (capillary number) and h (non-dimensionalized distance between source and sink). When the location of the sink is above the source, velocity on the free surface converges and a cusp occurs on the free surface for the value of Ca above some critical capillary number.

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Flow Structure of the Wake behind an Elliptic Cylinder Close to a Free Surface

  • Daichin;Lee, Sang-Joon
    • Journal of Mechanical Science and Technology
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    • v.15 no.12
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    • pp.1784-1793
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    • 2001
  • The flow fields around an elliptic cylinder of axis ratio AR=2 adjacent to a free surface were investigated experimentally using a water channel. The main objective is to understand the effect of the free surface on the flow structure in the near-wake. The flow fields were measured by varying the depth of cylinder submergence, for each experimental condition, 350 velocity fields were measured using a single-frame PIV system and ensemble-averaged to obtain the spatial distribution of turbulent statics. For small submergence depths a large-scale eddy structure was observed in the near-wake, causing a reverse flow near the free surface, downstream of the cylinder. As the depth of cylinder submergence was increased, the flow speed in the gap region between the upper surface of the cylinder and the free surface increased and formed a substantial jet flow. The general flow structure of the elliptic cylinder is similar to previous results for a circular cylinder submerged near to a free surface. However, the width of the wake and the angle of downward deflection of the shear layer developed from the lower surface of the elliptic cylinder are smaller tan those for a circular cylinder.

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Optimization of the Mixing Flow in an Agitated Tank

  • Yoo, Dal-Hyun;Yang, Si-Young;Choi, Youn-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.151-157
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    • 2005
  • In the chemical, mineral and electronics industries, mechanically stirred tanks are widely used for complex liquid and particle mixing processes. In order to understand the complex phenomena that occur in such tanks, it is necessary to investigate flow field in the vessel. Most difficulty on the numerical analysis of stirred tank flow field focused particularly on free surface analysis. In order to decrease the dead zone and improve the flow efficiency of a system with free surface, this paper presents a new method that overcomes free surface effects by properly combining the benefits of using experiment and 3-D CFD. This method is applied to study the mixing flow in an agitated tank. From the results of experimental studies using the PIV (particle image velocimetry) system, the distribution of mixing flow including free surface are obtained. And these values that are expressed as a velocity vector field have been patched for simulating the free surface. The results of velocity distribution obtained by 3-D CFD are compared with those of experimental results. The experimental data and the simulation results are in good agreement.

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Numerical Analysis of Flow around Propeller Rotating Beneath Free Surface (자유수면 아래에서 회전하는 프로펠러 주위 유동 수치 해석)

  • Park, Il-Ryong
    • Journal of Ocean Engineering and Technology
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    • v.29 no.6
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    • pp.427-435
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    • 2015
  • This paper provides the numerical results of a simulation of the flow around a propeller working beneath the free surface. A finite volume method is used to solve the unsteady Reynolds averaged Navier-Stokes (URANS) equations, where the wave-making problem is solved using a volume-of-fluid (VOF) method. The numerical analysis focuses on the propeller wake structure affected by the free surface, where we consider another free surface boundary condition that treats the free surface as a rigid wall surface. The propeller wake under the effect of these two free surface conditions shows a reduction in the magnitude of the longitudinal and vertical flow velocities, and its vortical structures strongly interact with the free surface. The thrust and torque coefficient under the free surface effect decrease about 3.7% and 3.1%, respectively. Finally, the present numerical results show a reasonable agreement with the available experimental data.

Past Performance and Earnings Management: The Effect of Free Cash Flow

  • SARI, Martdian Ratna;DJOHANPUTRO, Bramantyo;KOUNTUR, Ronny
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.37-43
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    • 2021
  • The main objective of this study is to discuss the effect of free cash flow as a moderating variable on managers' decisions as regard earnings management. Companies with free cash flow are expected to refrain from taking opportunistic actions such as earnings management. The research used quantitative methods with sub-group moderating analysis. It is found that there is a significant relationship between past performance and earnings management, where the free cash flow is the moderating variable. The effect of past performance on earnings management is shown to slightly increase as free cash flow is considered. The findings of this study prove that earnings management is a practice that is often done by utilizing the flexibility of accounting recording and recognition mechanisms. Past performance becomes the main variable in encouraging managers to manage earnings by reducing revenue in the current period. This research can also be a reference in explaining managerial behavior and can be a reference to improving ethical human resource capabilities. This research focuses on companies in Indonesia that conduct earnings management by lowering profits as a result of declining past performance and examines aspects of free cash flow that reinforces the conduct of earnings management.

Transitions between Uncontrolled Submerged and Uncontrolled Free in Low-Head Ogee Spillway

  • Hong, Seung Ho;Hong, Da Hee;Song, Yang Heon;Lee, Jeong Myeong;Jegal, Jin A
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.155-155
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    • 2022
  • Low head, ogee spillways is popularly used to defense against floods as well as to provide water for irrigation. Spillway is also used to assess compliance with water quality regulations by controlling amount of discharge to the downstream of a channel. For the purpose of water resource management and/or environmental aspects as explained above, the flow discharge through spillways need to be correctly rated as a function of geometry and hydraulic variables. Typically, four flow conditions are encountered during the operation of spillway: (a) uncontrolled free flow (UF); (b) uncontrolled submerged flow (US); controlled free flow (CF); and controlled submerged flow (CS), and each condition has a unique rating equation. However, one of the tricky part of the spillway operation is finding correct flow type over the spillway because structures can operate under both submerged and free flow conditions, and the types are continuously changing over time depending on the amount of discharge, head water and tail water elevation. Quite obviously, if the wrong rating curve relationship is applied because of misjudgment of the flow type due to a transition, a serious error can occur. Thus, an hydraulic model study of one of spillway structure located in South Florida was conducted for the purpose of developing transition relationships. In this presentation, US to UF transition is highlighted.

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Flow Characteristics of Sweeping Jet Issued by a Feedback-free Fluidic Oscillator (피드백이 없는 유체진동기에서 분사되는 Sweeping jet의 유동 특성)

  • Nam, Sanghyun;Kim, Donguk;Kim, Kyung Chun
    • Journal of the Korean Society of Visualization
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    • v.18 no.1
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    • pp.50-58
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    • 2020
  • This paper presents flow characteristics of a sweeping jet issued by a feedback-free fluidic oscillator. Overall flow characteristics of feedback-free sweeping jet (FFSJ) were analyzed using flow visualization. The feedback-free sweeping jet has a sinusoidal external flow pattern. The oscillating frequency of the FFSJ is three times higher than that of a conventional sweeping jet at the same Reynolds number. Flow structure and turbulence characteristics were investigated using time-resolved particle image velocimetry (TR-PIV). In instantaneous velocity fields, the flow did not stay at ends but changed the direction continuously in contrast to the conventional sweeping jet. Velocity distributions at each plane which were extracted from mean velocity field has Gaussian distribution, which is similar with a circular jet. The sweep angles were constant as 45° at all Reynolds numbers in the high flow rate regime.

AN EFFICIENT INCOMPRESSIBLE FREE SURFACE FLOW SIMULATION USING GPU (GPU를 이용한 효율적인 비압축성 자유표면유동 해석)

  • Hong, H.E.;Ahn, H.T.;Myung, H.J.
    • Journal of computational fluids engineering
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    • v.17 no.2
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    • pp.35-41
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    • 2012
  • This paper presents incompressible Navier-Stokes solution algorithm for 2D Free-surface flow problems on the Cartesian mesh, which was implemented to run on Graphics Processing Units(GPU). The INS solver utilizes the variable arrangement on the Cartesian mesh, Finite Volume discretization along Constrained Interpolation Profile-Conservative Semi-Lagrangian(CIP-CSL). Solution procedure of incompressible Navier-Stokes equations for free-surface flow takes considerable amount of computation time and memory space even in modern multi-core computing architecture based on Central Processing Units(CPUs). By the recent development of computer architecture technology, Graphics Processing Unit(GPU)'s scientific computing performance outperforms that of CPU's. This paper focus on the utilization of GPU's high performance computing capability, and presents an efficient solution algorithm for free surface flow simulation. The performance of the GPU implementations with double precision accuracy is compared to that of the CPU code using an representative free-surface flow problem, namely. dam-break problem.