• Title/Summary/Keyword: SCS method

Search Result 1,154, Processing Time 0.02 seconds

An Evaluation on Use Suitability of Recreation Resource in Natural Parks (자연공원 휴양자원의 이용적합성 평가)

  • 배민기;신원섭
    • Korean Journal of Environment and Ecology
    • /
    • v.17 no.3
    • /
    • pp.285-294
    • /
    • 2003
  • The purpose of this paper is to provide useful knowledge for recreation management in natural park(NP) by evaluating use suitability of recreation resource. We had obtained data through a questionnaire, which surveyed 385 visitors at 6 of the 73 NP in Korea in 2001, based on stratified sampling method. We have analyzed the data using the multiple regression method. We found that 1) in bivariate analysis, the relationships between use suitability and all the recreation resources are fairly high and statistically significant. The higher the degree of recreation resources, the higher the degree of use suitability. 2) in multivariate analysis, topography, social resource(SR), cultural resource(CR), landscape, smell, color and sound(SCS) have been turned out to be statistically significant at one percent level. 3) the direction of relationship between topography, SR, CR, landscape, SCS and use suitability is same. 4) in relative contribution of the use suitability of recreation resource, level of topography has been turned out to have about 1.05, 1.56, 2.16 and 2.70 times more important than that of SCS, SR, landscape, topography, respectively This results will be used for a criterion for recreation resource evaluation and a settlement of management priority and increasing user's satisfaction.

Analysis of Regional Antecedent Wetness Conditions Using Remotely Sensed Soil Moisture and Point Scale Rainfall Data (위성토양수분과 지점강우량을 이용한 지역 선행습윤조건 분석)

  • Sunwoo, Wooyeon;Kim, Daeun;Hwang, Seokhwan;Choi, Minha
    • Korean Journal of Remote Sensing
    • /
    • v.30 no.5
    • /
    • pp.587-596
    • /
    • 2014
  • Soil moisture is one of the most important interests in hydrological response and the interaction between the land surface and atmosphere. Estimation of Antecedent Wetness Conditions (AWC) which is soil moisture condition prior to a rainfall in the basin should be considered for rainfall-runoff prediction. In this study, Soil Wetness Index (SWI), Antecedent Precipitation Index ($API_5$), remotely sensed Soil Moisture ($SM_{rs}$), and 5 days ground Soil Moisture ($SM_{g5}$) were selected to estimate the AWC at four study area in the Korean Peninsula. The remotely sensed soil moisture data were taken from the AMSR-E soil moisture archive. The maximum potential retention ($S_{obs}$) was obtained from direct runoff and rainfall using Soil Conservation Service-Curve Number (SCS-CN) method by rainfall data of 2011 for each study area. Results showed the great correlations between the maximum potential retention and SWI with a mean correlation coefficient which is equal to -0.73. The results of time length representing the time scale of soil moisture showed a gap from region to region. It was due to the differences of soil types and the characteristics of study area. Since the remotely sensed soil moisture has been proved as reasonable hydrological variables to predict a wetness in the basin, it should be continuously monitored.

A Study of Soil Moisture Retention Relation using Weather Radar Image Data

  • Choi, Jeongho;Han, Myoungsun;Lim, Sanghun;Kim, Donggu;Jang, Bong-joo
    • Journal of Multimedia Information System
    • /
    • v.5 no.4
    • /
    • pp.235-244
    • /
    • 2018
  • Potential maximum soil moisture retention (S) is a dominant parameter in the Soil Conservation Service (SCS; now called the USDA Natural Resources Conservation Service (NRCS)) runoff Curve Number (CN) method commonly used in hydrologic modeling for event-based flood forecasting (SCS, 1985). Physically, S represents the depth [L] soil could store water through infiltration. The depth of soil moisture retention will vary depending on infiltration from previous rainfall events; an adjustment is usually made using a factor for Antecedent Moisture Conditions (AMCs). Application of the method for continuous simulation of multiple storms has typically involved updating the AMC and S. However, these studies have focused on a time step where S is allowed to vary at daily or longer time scales. While useful for hydrologic events that span multiple days, this temporal resolution is too coarse for short-term applications such as flash flood events. In this study, an approach for deriving a time-variable potential maximum soil moisture retention curve (S-curve) at hourly time-scales is presented. The methodology is applied to the Napa River basin, California. Rainfall events from 2011 to 2012 are used for estimating the event-based S. As a result, we derive an S-curve which is classified into three sections depending on the recovery rate of S for soil moisture conditions ranging from 1) dry, 2) transitional from dry to wet, and 3) wet. The first section is described as gradually increasing recovering S (0.97 mm/hr or 23.28 mm/day), the second section is described as steeply recovering S (2.11 mm/hr or 50.64 mm/day) and the third section is described as gradually decreasing recovery (0.34 mm/hr or 8.16 mm/day). Using the S-curve, we can estimate the hourly change of soil moisture content according to the time duration after rainfall cessation, which is then used to estimate direct runoff for a continuous simulation for flood forecasting.

Development and Verification of PZT Actuating Micro Tensile Tester for Optically Functional Materials

  • Kim Seung-Soo;Lee Hye-Jin;Lee Hyoung-Wook;Lee Nak-Kyu;Han Chang-Soo;Hwang Jai-Hyuk
    • International Journal of Control, Automation, and Systems
    • /
    • v.3 no.3
    • /
    • pp.477-485
    • /
    • 2005
  • This paper is concerned with the development of a micro tensile testing machine for optically functional materials such as single or poly crystalline silicon and nickel film. This micro tensile tester has been developed for testing various types of materials and dimensions. PZT type actuation is utilized for precise displacement control. The specifications of the PZT actuated micro tensile testers developed are as follows: the volumetric size of the tester is desktop type of 710mm' 200mm' 270mm; the maximum load capacity and the load resolution in this system are IKgf and 0.0152mgf respectively and; the full stroke and the stoke resolution of the PZT actuator are $1000{\mu}m$ and 10nm respectively. Special automatic specimen installing and setting equipment is applied in order to prevent unexpected deformation and misalignment of specimens during handling of specimens for testing. Nonlinearity of the PZT actuator is compensated to linear control input by an inverse compensation method that is proposed in this paper. The strain data is obtained by ISDG method that uses the laser interference phenomenon. To test the reliance of this micro tensile testing machine, a $200{\mu}m$ thickness nickel thin film and SCS (Single Crystalline Silicon) material that is made with the MEMS fabrication process are used.

Post-processing Technique Based on POCS Using EZW (EZW를 이용한 POCS 기반의 후처리 기법)

  • Kim, Hyo-Kak;Kwon, Goo-Rak;Kim, Yoon;Ko, Sung-Jea
    • Proceedings of the IEEK Conference
    • /
    • 2005.11a
    • /
    • pp.427-430
    • /
    • 2005
  • In this paper, we propose a new post-processing method, based on the theory of the projection onto convex sets (POCS) to reduce the blocking artifacts in decoded images. We propose a new smoothness constraint set (SCS) and its projection operator in the wavelet transform (WT) domain to remove unnecessary high-frequency components caused by blocking artifacts. We also propose a new method to find and preserve the original high frequency components of the image edge. Experimental results show that the proposed method can not only achieve a significantly enhanced subjective quality, but also have the PSNR improvement in the output image.

  • PDF

The optimisation method of the elastic-plastic spatial grid structures

  • Karczewski, Jan
    • Steel and Composite Structures
    • /
    • v.3 no.4
    • /
    • pp.277-287
    • /
    • 2003
  • The low boundary of load carrying capacity of the elastic-plastic spatial grid structures depend on numerous values and their variability assumed in designing process. Analysed influence all this values in searching for optimal variant of the structure lead to too great problem even taking into consideration actual computational power we have in disposal. Therefore one can take only a few values which have greatest influence on the optimal choice. In optimal analysis of the elastic-plastic spatial grid structures the previously proposed method with subsequent modification (Karczewski 1980), (Karczewski, Barszcz and Donten 1996), (Karczewski and Donten 2001) as well as computer program which was worked out by Donten K. to make possible practical utilisation this method was employed. The paper deal with evaluation of influence dimensions of particular values for choice of optimal variant of the structure. One among this values is distribution of the struts in the structure.

Design of steel and composite beams with web openings - Verification using finite element method

  • Chung, K.F.;Ko, C.H.;Wang, A.J.
    • Steel and Composite Structures
    • /
    • v.5 no.2_3
    • /
    • pp.203-233
    • /
    • 2005
  • This paper presents the findings of a design development project for perforated beams fully integrated with building services. A unified design approach for both steel and composite beams with large rectangular web openings is proposed which is based on plastic design methods and formulated in accordance with analytical structural design principles. Moreover, finite element models are established after careful calibration against test data, and comparison on the predicted ultimate loads of two composite beams with rectangular web openings from the finite element models and the proposed design method is also presented. It is demonstrated that the proposed design method is able to predict the ultimate loads of composite beams with rectangular web openings against 'Vierendeel' mechanism satisfactorily.

Deformation and stress analysis of a sandwich cylindrical shell using HDQ Method

  • Shokrollahi, Hassan
    • Steel and Composite Structures
    • /
    • v.27 no.1
    • /
    • pp.35-48
    • /
    • 2018
  • In this paper, the response of a sandwich cylindrical shell over any sort of boundary conditions and under a general distributed static loading is investigated. The faces and the core are made of some isotropic materials. The faces are modeled as thin cylindrical shells obeying the Kirchhoff-Love assumptions. For the core material it is assumed to be thick and the in-plane stresses are negligible. The governing equations are derived using the principle of the stationary potential energy. Using harmonic differential quadrature method (HDQM) the equations are solved for deformation components. The obtained results primarily are compared against finite element results. Then, the effects of changing different parameters on the stress and displacement components of sandwich cylindrical shells are investigated.

Multi-material topology optimization of Reissner-Mindlin plates using MITC4

  • Banh, Thien Thanh;Lee, Dongkyu
    • Steel and Composite Structures
    • /
    • v.27 no.1
    • /
    • pp.27-33
    • /
    • 2018
  • In this study, a mixed-interpolated tensorial component 4 nodes method (MITC4) is treated as a numerical analysis model for topology optimization using multiple materials assigned within Reissner-Mindlin plates. Multi-material optimal topology and shape are produced as alternative plate retrofit designs to provide reasonable material assignments based on stress distributions. Element density distribution contours of mixing multiple material densities are linked to Solid Isotropic Material with Penalization (SIMP) as a design model. Mathematical formulation of multi-material topology optimization problem solving minimum compliance is an alternating active-phase algorithm with the Gauss-Seidel version as an optimization model of optimality criteria. Numerical examples illustrate the reliability and accuracy of the present design method for multi-material topology optimization with Reissner-Mindlin plates using MITC4 elements and steel materials.

A study on Average CN Estimation in River Basin using Satellite Data

  • Kwon, Bong-kyum;Jo, Myung-Hee;Ahn, Seung-Sep;Kiyoshi, Yamada
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.499-499
    • /
    • 2002
  • The goal of this study is to apply and evaluate the precipitation outflow in river basin using satellite data and GIS for proposing the efficient watershed management method. Not only precipitation outflow data but also various spatial data such as digital map, soil map, geologic map and multi-temporal TM images were used. Using landcover classification result and soil map were applied to estimate the average CN. The CN value of 63.37 by SCS method was produced in AMC-2 condition otherwise the result of direct estimation with observation method was 63 CN value. The relative error of two results was 0.59%. It can be possible to apply the satellite data for precipitation outflow analysis. For more accurate and credible analysis of this, the more multi-temporal satellite and real observation data will be needed.

  • PDF