• Title/Summary/Keyword: rough

Search Result 2,780, Processing Time 0.033 seconds

Integration rough set theory and case-base reasoning for the corporate credit evaluation (러프집합이론과 사례기반추론을 결합한 기업신용평가 모형)

  • Roh, Tae-Hyup;Yoo Myung-Hwan;Han In-Goo
    • The Journal of Information Systems
    • /
    • v.14 no.1
    • /
    • pp.41-65
    • /
    • 2005
  • The credit ration is a significant area of financial management which is of major interest to practitioners, financial and credit analysts. The components of credit rating are identified decision models are developed to assess credit rating an the corresponding creditworthiness of firms an accurately ad possble. Although many early studies demonstrate a priori which of these techniques will be most effective to solve a specific classification problem. Recently, a number of studies have demonstrate that a hybrid model integration artificial intelligence approaches with other feature selection algorthms can be alternative methodologies for business classification problems. In this article, we propose a hybrid approach using rough set theory as an alternative methodology to select appropriate attributes for case-based reasoning. This model uses rough specific interest lies in lthe stable combining of both rough set theory to extract knowledge that can guide dffective retrevals of useful cases. Our specific interest lies in the stable combining of both rough set theory and case-based reasoning in the problem of corporate credit rating. In addition, we summarize backgrounds of applying integrated model in the field of corporate credit rating with a brief description of various credit rating methodologies.

  • PDF

Prediction of Maneuverability and Efficiency for a Mobile Robot on Rough Terrain through the development of a Testbed for Analysis of Robot-terrain interaction (지형-로봇간의 상호작용 분석 장치의 개발을 통한 야지 주행 로봇의 기동성 및 효율성 예측)

  • Kim, Jayoung;Lee, Jihong
    • The Journal of Korea Robotics Society
    • /
    • v.8 no.2
    • /
    • pp.116-128
    • /
    • 2013
  • This paper focuses on development of a testbed for analysis of robot-terrain interaction on rough terrain and also, through one wheel driving experiments using this testbed, prediction of maximum velocity and acceleration of UGV. Firstly, from the review regarding previous researches for terrain modeling, the main variables for measurement are determined. A testbed is developed to measure main variables related to robot-terrain interaction. Experiments are performed on three kinds of rough terrains (grass, gravel, and sand) and traction-slip curves are obtained using the data of the drawbar pull and slip ratio. Traction-slip curves are used to predict driving performance of UGV on rough terrain. Maximum velocity and acceleration of UGVs are predicted by the simple kinematics and dynamics model of two kinds of 4-wheel mobile robots. And also, driving efficiency of UGVs is predicted to reduce energy consumption while traversing rough terrains.

Electromagnetic Wave Propagation Characteristics from Large Scale Random Rough Surfaces (큰 규모의 불규칙 조면에 의한 전자파 전파 특성)

  • Yoon Kwang-Yeol;Chai Yong-Yoong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.17 no.4 s.107
    • /
    • pp.393-399
    • /
    • 2006
  • In this paper we applied a ray tracing method to estimate the scattering characteristics from large scale random rough surfaces. For the electromagnetic field evaluation, we have used the diffracted coefficient of the knife edge diffraction for the diffracted rays and Fresnel's reflection coefficients in connection with reflected rays. In addition, we examine to search for the traced rays using the imaging method which can be obtained all rays to arrived at receivers accurately and the diffracted field from rough surfaces is considered. Numerical examples have been carried out for the scattering characteristics of an ocean wave-like rough surface and delay spread characteristics of a building-like surface. In the present work we have demonstrated that the ray tracing method is effective to numerical analysis of a rough surface scattering.

Measurements of Mechanical Behavior of Rough Rice under Impact Loading (벼의 충격(衝擊) 특성(特性)에 관한 연구(硏究))

  • Cha, J.Y.;Koh, H.K.;Noh, S.H.;Kim, M.S.;Kim, Y.H.
    • Journal of Biosystems Engineering
    • /
    • v.14 no.3
    • /
    • pp.207-214
    • /
    • 1989
  • In this study, impact force and angular displacement of the pendulum were measured by the load cell and potentiometer. Mechanical behavior of rough rice under impact loading was able to analyze precisely and efficiently, because measured data were accumulated and handled by the automatic data acquisition system making use of microcomputer system. Impact force and angular displacement were measured with a resolutiln of 1/1500 seconds in time. Mechanical behavior such as force and energy at rupture point of Japonica type and Indica type rough rice were measured with this system. After impact loading, the damage of rough rice was examined with the microphotograph and an allowable impact force was measured. The results obtained in this study are summarized as follows. 1. Machanical behavior of rough rice under impact loading was analyzed precisely and efficiently because measured data were accumulated and handled by this data acquisition system. 2. Rupture force and rupture energy of rough rice were appeared to be the lowest value in the range of 16 to 18 % moisture content, and rupture force and rupture energy of Japonica type were higher than those of Indica type in each level of moisture content. 3. From the result of the damage examined after the impact loading, allowable impact force was the lowest in the range of 16 to 18 % moisture content, and the value of the allowable impact force of Japonica type was higher than that of Indica type in each level of moisture content.

  • PDF

The Relationship among a Father's Rough-and-Tough Play, Child's Emotional Expressiveness and Adaptive Emotional Regulation: The Moderated Mediation Effect of a Father's Play Participation Attitud (아버지의 거친신체놀이, 유아의 정서표현성과 적응적 정서조절의 관계: 아버지 놀이참여태도의 조절된 매개효과)

  • Jihyun Oh
    • Korean Journal of Childcare and Education
    • /
    • v.19 no.1
    • /
    • pp.23-41
    • /
    • 2023
  • Objective: The purpose of this study is to explain in detail the factors of the father's play interaction that predict children's adaptive emotional regulation. This study examined the moderated mediation effect of a father's rough-and-tough play toward a child's emotional expressiveness and the father's play participation attitude on the child's adaptive emotional regulation. Methods: The study participants included 309 fathers of children aged from 3 to 5 years. Data were analyzed using models of the PROCESS Macro. Results: As a result of this research, the relationship of the father's rough-and-tough play with the child's adaptive emotional regulation was that this was indeed mediated by the child's negative emotional expressiveness. Additionally, the father's responsive and fun play attitude moderated the relationship between the father's rough-and-tough play and the child's adaptive emotional regulation. Further, the father's responsive and fun play attitude according to level had a moderated mediation effect. Conclusion/Implications: These results are meaningful in that they derives a mechanism for why and how a father's rough-and-tough play affects children's adaptive emotional regulation.

Automatic Tool Selection and Path Generation for NC Rough Cutting of Sculptured Surface (자유곡면의 NC 황삭가공을 위한 자동 공구 선정과 경로 생성)

  • Hong, Sung Eui;Lee, Kun woo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.11 no.6
    • /
    • pp.28-41
    • /
    • 1994
  • An efficient algorithm is proposed to select the proper tools and generate their paths for NC rough cutting of dies and molds with sculptured surfaces. Even though a milling process consists of roughing, semi-finishing, and finishing, most material is removed by a rough cutting process. Therfore it can be said that the rough cutting process occupy an important portion of the NC milling process, and accordingly, an efficient rough cutting method contributes to an efficient milling process. In order work, the following basic assumption is accepted for the efficient machining. That is, to machine a region bounded by a profile, larger tools should be used in the far inside and the region adjacent to relatively simple portion of the boundary while smaller tools are used in the regions adjacent to the relatively complex protion. Thus the tools are selected based on the complexity of the boundary profile adjacent to the region to be machined. An index called cutting path ratio is proposed in this work as a measure of the relative complexity of the profile with respect to a tool diameter. Once the tools are selected, their tool paths are calculated starting from the largest to the smallest tool.

  • PDF

Rheological Properties of Rough Rice (II) -Compressive Creep of Rough Rice Kernel- (벼의 리올러지 특성(特性)(II) -곡립(穀粒)의 압축(壓縮)크리이프-)

  • Kim, M.S.;Kim, S.R.;Park, J.M.
    • Journal of Biosystems Engineering
    • /
    • v.15 no.3
    • /
    • pp.219-229
    • /
    • 1990
  • The compression creep behavior of grains when loaded depends not only on load but also on duration of load application. The most common methods of studying the load-time characteristics of agricultural products is by employing rheological models such as Burger's model. However it is sometimes not sufficient to describe the viscoelastic behavior of grains to be Burger's model. For this reason, this study was conducted to develop the rheological model which represented the creep compliance response of the rough rice kernel and was a function of initial stress applied and time. The effects of the initial stress applied and the moisture content on the compression creep behavior of the rough rice kernel were analyzed. The results were obtained from the study as follows: 1. Since the viscoelastic behavior of the rough rice kernel was nonlinear, the transient and steady state creep compliance was satisfactorily modelled as follows: $$J({\sigma},t)=A{\sigma}^B[C+Dt-exp(-Ft)]$$ But, for the every stress applied, the compression creep behavior of the samples tested can be well described by Burger's model respectively. 2. The creep compliance, the instantaneous elastic strain, the retarded elastic strain and the viscous strain of the sample tested generally increased in magnitude with increasing the applied initial stress and the moisture content used in the tests. At low moisture content, the creep compliance for the Japonica-type rough rice kernel Was a little higher than those for Indica-type and at high moisture content, vice versa at high moisture content. 3. The retardation times of the samples had not an uniform tendency by the initial stress and the moisture content. The retardation times ranged from 0.66 to 6.76 seconds, and the creep progressed from transient to steady state at a relatively high rate. 4. The less viscous strain than the instantaneous elastic strain for the samples tested indicated that rough rice kernel behaved as a viscoelastic body characterized by elasticity than viscosity.

  • PDF

The Changes of Rough Surfaced Endoplasmic Reticulm of Lymph Node Cells Stimulated by Antigen (항원성 자극을 받은 임파절세포의 Rough Surfaced Endoplasmic Reticulum 의 변화)

  • Lee Chang-Soo;Kwon Sae-Hoon;Sohn Tae-Joong
    • Applied Microscopy
    • /
    • v.3 no.1
    • /
    • pp.23-28
    • /
    • 1973
  • The changes of rough surfaced endoplasmic reticulum of plasma cells in the regional lymph node after injection of Bovine Gamma Globulin summarized as follow: The rough ER of plasma cells before antigenic stimulation shows flattened sac but changed to vesicular at 3rd day and vacuolar at 7th to 10th day. lntradisternal granules are appeared within the lumina or rough ER at 7th to 10th day. The rough ER is changed to distended sac or flattened sac at 20th day. The results suggest that normally flattened sac of rough ER is changed to vesicular and then to vacuolar after antigenic stimulation. But they are returned to distended sac or flattened sac with disappearance of antigenic stimuli.

  • PDF

Effect of presurfacing on drying rate and drying defect of Quercus grosseserrata BI. (전평삭처리(前平削處理)가 물참나무의 건조속도(乾燥速度)와 건조결함(乾燥缺陷)에 미치는 영향(影響))

  • Han, Gyu-Seong;Jung, Hee-Suk
    • Journal of the Korean Wood Science and Technology
    • /
    • v.14 no.4
    • /
    • pp.29-39
    • /
    • 1986
  • To investigate the effect of presurfacing, both 25mm rough and pre surfaced oak boards (Quercus grosseserrata BI.) were dried in the same dry kiln condition. Drying curves, drying strains and drying defects of rough and presurfaced boards were compared. The results obatained are as follows. 1. Average drying rate of rough and presurfaced boards from green to 10% M.C. was 0.276%/hr. and 0.284%/hr., respectively. 2. At the early stage of drying, in case of rough boards, maximum tensile strain of outer slices was $-24.2{\times}10^{-4}$mm/mm and maximum compressive strain of innermost slices was $13.0{\times}10^{-4}$mm/mm, and in case of pre surfaced boards, maximum tensile strain of outer slices was $-14.5{\times}10^{-4}$mm/mm and maximum compressive strain of innermost slices was $28.1{\times}10^{-4}$mm/mm. And in both cases, stress reversal occurred at about 40% M.C.. 3. Maximum surface checking appeared at about 40% M.C.. Of the 10 rough boards. 6 hoards contained surface checks, but presurfaced boards did not contained surface checks after drying. And the results of end checking were similar to those of surface checking. But, honeycomb was not found in both cases. 4. Board shrinkage. warp and casehardening of presurfaced boards were similar to those of rough boards. But, collapse of prsurfaced boards was less than that of rough boards.

  • PDF

The Study on Rough Colony Type Mutant of Pseudomoms mori(Boyer et Lambert) Stevens, caused Mulberry Bacterial Blight: Pathogenicity and General Characteristics (뽕나무 세균성위축병균 Pseudomonas mori (Boyer et Lambert) STEVENS의 Rough Colony Type Mutant에 관한 연구 ; 병원성 및 일반적 성질)

  • Yi Young Keun;Kim Jong Wan;Cho Yong Sup
    • Korean journal of applied entomology
    • /
    • v.16 no.1 s.30
    • /
    • pp.21-31
    • /
    • 1977
  • The study has been carried out to compare the pathogenicity, physiological characteristics and genetic reliability between rough colony type strain and smooth colony type strains of Pseudomonas mori (Boyer et Lambert) Stevens which were isolated from diseased plant parts in 5 different areas throughout country. The results are summarized as follow. 1. The rough colony type strain showed more agressive reactions to tested host plant varieties than smooth colony type strains though there was no differences in the appearence of lesion types caused by both strains. 2. Both colony types were differentiated morphologically in that the rough colony type strain was having more than 200r long filamentous body without flagella where as the smooth colony type strains have short rods with one or several polar flagella. 3. The colony of smooth type strains was circular, entire, smooth and opaque, while the rough type strain shelved endulated, irregular margin, rough and wrinkled colony on nutrient agar media. 4. There were no differences between both colony types in the physiological and serological test. 5. Both of smooth and rough colony type strains showed genetic reliability through more than 100 succeeding cultures on the media, and were stable to various chemicals such as 1 to 3 percent of NaCl, 5 kinds of organic acid and 4 kinds of antibiotics.

  • PDF