• Title/Summary/Keyword: regression formulas

Search Result 115, Processing Time 0.02 seconds

Development of the Basic Bodice Pattern Depending on Shoulder Types -focused on young women in their twenties- (어깨 유형에 따른 길 원형 설계 -20대 여성 중심으로-)

  • 김민진;이정란
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.27 no.5
    • /
    • pp.463-474
    • /
    • 2003
  • In this research, adult women's shoulder types were Classified through direct and indirect measurements to present a judging individual body size according to the type. Also, regression formula by shoulder types were calculated and presented the basic bodice pattern. The results were as follows: 1. The result of factor analysis indicated that 6 factors were extracted through factor analysis and those factors comprised 66.1 to of total variance. 2. By using factor scores, cluster analysis was carried out and subject were classified into 5 clusters. Type 1 was the inclined shoulders, wide shoulders and passive posture. Type 2 was the front type shoulders and active posture. Type 3 was the thick shoulders and back type shoulders. Type 4 was the narrow shoulders. Type f was the drooped shoulders, thin shoulder and sway posture. 3. The body types of individuals were judged by discriminant analysis. 4. After setting 4 items such as the bust girth, posterior waist length, neck base girth and waist girth as representative items and regression formulas were presented. the superiority of the final basic bodice patterns were demonstrated by high approval rate of the subjects who participated in testing.

Investigations of elastic vibration periods of tall reinforced concrete office buildings

  • Al-Balhawi, Ali;Zhang, Binsheng
    • Wind and Structures
    • /
    • v.29 no.3
    • /
    • pp.209-223
    • /
    • 2019
  • The assessment of wind-induced vibration for tall reinforced concrete (RC) buildings requires the accurate estimation of their dynamic properties, e.g., the fundamental vibration periods and damping ratios. In this study, RC frame-shear wall systems designed under gravity and wind loadings have been evaluated by utilising 3D FE modelling incorporating eigen-analysis to obtain the elastic periods of vibration. The conducted parameters consist of the number of storeys, the plan aspect ratio (AR) of buildings, the core dimensions, the space efficiency (SE), and the leasing depth (LD) between the internal central core and outer frames. This analysis provides a reliable basis for further investigating the effects of these parameters and establishing new formulas for predicting the fundamental vibration periods by using regression analyses on the obtained results. The proposed constrained numerically based formula for vibration periods of tall RC frame-shear wall office buildings in terms of the height of buildings reasonably agrees with some cited formulas for vibration period from design codes and standards. However, the same proposed formula has a high discrepancy with other cited formulas from the rest of design codes and standards. Also, the proposed formula agrees well with some cited experimentally based formulas.

Wheel Load Distribution Factor for Girder Moment and Shear Force of Skew Plate Girder Bridges (판형사교 거더의 휨모멘트와 전단력에 대한 하중분배계수)

  • Seo, Chang-Bum;Song, Jae-Ho
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.5 no.1 s.16
    • /
    • pp.33-43
    • /
    • 2005
  • The girder wheel load distribution factors stated in the Korean Bridge Specification and AASHTO Standard Specifications do not account for the effect of skewness of plate girders, and very little research has been conducted on girder wheel load distribution factors. The purpose of the study is to propose load distribution factor formulas for skew plate girder bridges which comprise various parameters through structural analysis. To confirm the validity of finite element models used in this study analytic values are compared with the field test results. From the results it should be noted that span length is not such a dominant parameter compared with others. In view of better load distribution of interior girders, skew arranged cross beams or bracing are preferable, furthemore bracing system is more effective than cross beam system. By means of regression analysis on the basis of analytic results wheel load distribution factor formulas are proposed and compared with current codes.

Girder Wheel Load Distribution Factor of Skew Plate Girder Bridges (강판형 사교의 거더분배계수에 관한 연구)

  • Seo, Chang-Bum;Song, Jae-Ho
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.9 no.1
    • /
    • pp.293-303
    • /
    • 2005
  • The girder wheel load distribution factors stated in the Korean Bridge Specification and AASHTO Standard Specifications do not account for the effect of skewness of plate girders, and very little research has been conducted on girder wheel load distribution factors. The purpose of the study is to propose load distribution factor formulas for skew plate girder bridges which comprise various parameters through structural analysis. To comprise the validity of finite element models used in this study analytic values are compared with the field test results. From the results it should be noted that span length is not such a dominant parameter compared with others. In view of better load distribution of interior girders, skew arranged cross beams or bracing are preferable, furthemore bracing system is more effective than cross beam system. By means of regression analysis on the basis of analytic results wheel load distribution factor formulas are proposed and compared with current codes.

A Study on Modelling Readability Formulas for Reading Instruction System (독서교육시스템을 위한 텍스트수준 측정 공식 구성에 관한 연구)

  • Choe, In-Sook
    • Journal of the Korean Society for information Management
    • /
    • v.22 no.3 s.57
    • /
    • pp.213-232
    • /
    • 2005
  • The purpose of this study is to determine factors affecting text difficulty and to model objective formulas which measure readability scores. Some readability-related factors such as total number of letters, total number of syllables, total number of unique syllables, total number of sentences and total number of paragraphs were found through correlation analysis. Some regression equations with these factors as their variables were produced through regression analysis. A model estimating readability score from total number of unique syllables was a good formula, while a model with two factors, total number of unique syllables and new syllable occurrence ratio, was a better enhanced one. The readability score represents detailed level so we can recommend students read texts corresponding to their reading levels.

A Study on Wheel Load Distribution Factors of Skew Steel Box Girder Bridges (강상자형 사교의 윤하중분배계수)

  • Seo, Chang-Bum;Song, Jae-Ho;Kim, Il-Soo
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.13 no.4 s.56
    • /
    • pp.148-158
    • /
    • 2009
  • Firstly the problems of existing foreign code concerning wheel load distribution factor for skew box girder bridges have been examined, and the main parameters which have effects on wheel load distribution factors are evaluated in this study. Further finite element analyses on various skew steel box girder bridges are carried out. Based on the analysis results, formulas to determine wheel load distribution factors are proposed using multiple regression analysis. It is found when using the proposed formulas in this study weak points of existing specifications could be improved and also time spent at structural analysis should be saved a lot, so that the validity and practicality could be verified.

Review of appropriateness of existing formula for estimating the depth of scour and the experimental study on development of the formula to estimated the depth of scour (기존 세굴심 산정식의 적정성 검토 및 세굴심 산정식 개발에 대한 실험적 연구세요)

  • Choi, Han-Kuy;Lee, Yeong-Seop
    • Journal of Industrial Technology
    • /
    • v.29 no.A
    • /
    • pp.67-75
    • /
    • 2009
  • In this study, the investigation of hydraulic characteristics and the pier data for the rivers in Youngseo area of Gangwon Province was carried out and the evaluation and comparison between the values from existing formulas and the values from the model tests was conducted, along with the statistical sensitivity analysis of the elements influencing the scour. As a result, the deviation between the values calculated from the existing formulas and the model tests appeared to be 1.09%~63.98% as the piers were getting larger, which indicated that the existing formulas were not appropriate to estimate the scour in the rivers in Gangwon area. And the formula which estimates the scour with the size of the pier only, among the existing ones, was far behind in estimating the sensitivity because of insufficient incorporation of the hydraulic characteristics, though it is convenient to estimate the value. The sensitivity analysis of the value from the model tests and the depth of the scour proved the significant impact on scour by the size of the pier and water depth, indicating 64% and 36%, respectively. In this study, the formula developed through the regression analysis performed based on the values from the model tests, which appeared to be appropriate for the rivers in Gangwon Province, was proposed.

  • PDF

Regression Algorithms Evaluation for Analysis of Crosstalk in High-Speed Digital System

  • Minhyuk Kim
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.18 no.6
    • /
    • pp.1449-1461
    • /
    • 2024
  • As technology advances, processor speeds are increasing at a rapid pace and digital systems require a significant amount of data bandwidth. As a result, careful consideration of signal integrity is required to ensure reliable and high-speed data processing. Crosstalk has become a vital area of research in signal integrity for electronic packages, mainly because of the high level of integration. Analytic formulas were analyzed in this study to identify the features that can predict crosstalk in multi-conductor transmission lines. Through the analysis, five variables were found and obtained a dataset consisting of 302,500, data points. The study evaluated the performance of various regression models for optimization via automatic machine learning by comparing the machine learning predictions with the analytic solution. Extra tree regression consistently outperformed other algorithms, with coefficients of determination exceeding 0.9 and root mean square logarithmic errors below 0.35. The study also notes that different algorithms produced varied predictions for the two metrics.

Comparative Evaluation of Formulas of Strength Reduction Factors for the Generation of an Inelastic Demand Spectrum (비탄성요구스펙트럼의 작성을 위한 강도감소계수 공식의 비교 평가)

  • Cho, Sung-Gook;Park, Woong-Ki;Joe, Yang-Hee
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.15 no.6
    • /
    • pp.33-44
    • /
    • 2011
  • The shape of an inelastic demand spectrum may have a major impact on the seismic evaluation results of a structure. The inelastic demand spectrum could be obtained by scaling down from the elastic response spectrum by applying the strength reduction factor (SRF). This study has investigated formulas for SRFs that were suggested by numerous previous studies. This paper compares their characteristics, including the shapes of the curves of the SRFs and the inelastic demand spectra that were produced by applying the various formulas for SRFs. The mean curve was computed from the SRF curves generated by the various formulas. This study derives a new formula for the SRF curve through regression analysis. From the comparative study, it is shown that the proposed formula for the SRF can generate the mean curve of the inelastic demand spectra which have been previously suggested by others.

Determination of Design Width for Medium Streams in the Han River Basin (한강유역의 중소하천에 대한 계획하폭 산정)

  • Jeon, Se-Jin;An, Tae-Jin;Park, Jeong-Eung
    • Journal of Korea Water Resources Association
    • /
    • v.31 no.6
    • /
    • pp.675-684
    • /
    • 1998
  • This paper presents the empirical formulas for determining the design-width for medium rivers in the Han river basin. The design flood, the watershed ares, and the channel slope of 216 medium rivers in the Han river basin are collected. the design width formulas are then determined by 1) the least squares (LS) method, 2)the least median squares (LMS) method, and 3) the reweighted least squares method based on the LMS (RLS). The six types of formulas are considered to determine the acceptable type for medium streams in the Han river basin. The root mean squared errors (RMSE), the absolute mean (AME) errors, and the mean errors (ME) are computed to test the formulas derived by three regression methods. It si found that the equation related stream width to the watershed area and the channel slope is acceptable for determining the design width for medium streams in the Han river basin. It is expected that the equations proposed by this study be used an index for determining the design-width for medium streams in the Han river basin.

  • PDF