• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.135-146
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• 2015

To provide the data necessary to determine the design wind speed for calculating the wind load acting on a greenhouse, we measured the wind speed below 10m height and analyzed the power law exponents at Buan and Gunwi. A wind speed greater than $5m{\cdot}s^{-1}$ is appropriate for calculating the power law exponent necessary to determine the wind speed distribution function according to height. We observed that the wind speed increased according to a power law function with increased height at Buan, showing a similar trend to the RDC and JGHA standards. Therefore, this result should be applied when determining the power law function for calculating the design wind speed of the greenhouse structure. The ordinary trend is that if terrain roughness increases the value of power law exponent also increases, but in the case of Gunwi the value of power law exponent was 0.06, which shows contrary value than that of the ordinary trend. This contrary trend was due to the elevations difference of 2m between tower installed and surrounding area, which cause contraction in streamline. The power law exponent started to decrease at 7 am, stopped decreasing and started to increase at 3 pm, and stopped increasing and remained constant at 12 pm at Buan. These changes correspond to the general change trends of the power law exponent. The calculated value of the shape parameter for Buan was 1.51, confirming that the wind characteristics at Buan, a reclaimed area near the coast, were similar to those of coastal areas in Jeju.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2013.10a
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• pp.261-269
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• 2013

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.91-97
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• 1998

The analysis model is the infinite body consisted of power law creep material containing a rigid inclusion with line crack shape subjected to the arbitrarily directional stress on an infinite boundary. The crack analysis is performed using the complex pseudo-stress function. The strain rate intensity factor is determined in the closed form as new fracture mechanics parmeter which represents the magnitudes of stress and strain rate near the tip in power law creep material.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.295-302
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• 2006

Over the past decades, a flocculation and/or sedimentation process have been adopted to remove pollutants from CSOs. It has been learned that major factors affecting settlement of pollutants are the particle size distribution, their settling velocities and their specific gravity. It is, therefore, a good idea to analyze the particle size distribution and settleability of CSOs pollutants in order to develop details in designing a process. Discussed in this study are pollutant characteristics of CSOs such as particle size distribution and settleability of pollutants. The power law function is applied and is found to be an effective and reliable index for expressing the particle size distribution of pollutants in CSOs. Based on the regression analysis it is observed that the derived constants of curves representing settling velocity profile are proportional to the initial concentration of particles and to the ${\beta}$-values of power law distributions.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.443-450
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• 2006

Micelles have been used in many applications. In these applications it is of prime importance to know how the critical micelle concentration (CMC), above which the micelles are formed, depends on temperature. Up to date polynomial functions of temperature have been used to describe temperature dependence of CMC. In this article it is shown that such polynomials are inadequate tools to express thermal behavior of CMC. Hence, new equations of CMC(T) have been derived on the basis of rigorous thermodynamic equations and experimental observations on CMCs. The new equations fit CMC data excellently, and further they lead to a power law for the CMC. The exponent of the power-law expression is 2 irrespective of surfactant systems, which points to the generality of newly found equations.

• Journal of Information Management
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• v.40 no.4
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• pp.135-150
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• 2009

Existing bibliometric laws have been established on the basis of well defined science journals with a long history. However, the history of technology innovation research in Korea is young and the scope of the research is diverse compared with other fields. The main purpose of this research can be summarized as follows : Can the traditional bibliometric laws be used to explain the young and diverse data derived from technology innovation studies in Korea. Second, we want to compare the explain ability of the power law, compared with the traditional laws in the field. Third, we propose a quasi index related to the well-known impact factor to measure the contribution of a journal or a group of journals to the development of innovation research in Korea. We confirmed Lotka's and Bradford's laws which are used to measure the productivity of researchers, but we could not support the validity of Price's Square Root law as Nicholls (1998) could not. On the citations to journals, Garfield's laws is not observed. However, the power law fits well the citations to author, journal, article, and book. The estimated parameters between 1.6 and 3.5 are similar to the values in the range of 1.5 and 3 in previous studies. Finally the quasi index shows that the influence of international leading journals on innovation research in Korea is weaker than on innovation studies in the world.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.740-743
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• 1995

The analysis model is the power law creep material containing an elliptical rigid inclusion subjected to the arbitrarily directional stress on infinite boundary. The stress analysis is performed using the conformal mapping function and complex pseudo-stress function. The stress distributions near an elliptical rigid inclusion are obtained with various ellipse shapes, strain hardening exponents and directions of applied stress.

• Journal of Korea Water Resources Association
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• v.49 no.5
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• pp.451-458
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• 2016

In order to infer regional flood frequency for ungauged watersheds, index flood method was applied for this study. To pursuit this given purpose, annual peak flood data for 22 watersheds located at the upstream of the Chungju Dam watershed were obtained from the spatial extension technique. The regionalization of mean annual flood was performed from extended flood data at 22 points. Based on the theory that flood discharge and watershed size follows the power law the regionalization generated the empirical relationship. These analyses were executed for the full size of the Chungju Dam watershed as one group and three different mid-size watersheds groups. From the results, the relationship between mean annual flood and watershed sizes follow the power law. We demonstrated that it is appropriate to use the relationship between specific flood discharges from the upper and lower watersheds in terms of estimating the floods for the ungaged watersheds. Therefore, not only the procedure of regional frequency analysis but also regionalizaion analaysis using finer discretization of the regions interest with respect to the regional frequency analyisis for the ungauged watersheds is important.

• Journal of Korea Water Resources Association
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• v.54 no.5
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• pp.335-345
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• 2021

The one-dimensional solute transport models have been developed for recent decades to predict behavior and fate of solutes in rivers. Transient storage model (TSM) is the most popular model because of its simple conceptualization to consider the complexity of natural rivers. However, the TSM is highly dependent on its parameters which cannot be directly measured. In addition, the TSM interprets the late-time behavior of concentration curves in the shape of an exponential function, which has been evaluated as not suitable for actual solute behavior in natural rivers. In this study, we suggested a stochastic approach to the solute transport analysis. We delineated the model development and model application to a natural river, and compared the results of the proposed model to those of the TSM. To validate the proposed model, a tracer test was carried out in the 4.85 km reach of Gam Creek, one of the first-order tributaries of Nakdong River, South Korea. As a result of comparing the power-law slope of the tail of breakthrough curves, the simulation results from the stochastic storage model yielded the average error rate of 0.24, which is more accurate than the 14.03 and 1.87 from advection-dispersion model and TSM, respectively. This study demonstrated the appropriateness of the power-law residence time distribution to the hyporheic zone of the Gam Creek.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.12
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• pp.2165-2171
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• 1997

The analysis model is the infinite power law creep material containing the rigid inclusion with crack shape. The present analysis is performed using the complex pseudo-stress function method. The strain rate intensity factor is developed as new fracture mechanics parameter which represents the stress and strain rate distribution near a crack tip in power law creep material. The strain rate intensity factor is developed in terms of Kolosoff stress functions.