• Title/Summary/Keyword: Shape Regression

Search Result 444, Processing Time 0.025 seconds

Seeking for the Determinants of Entrepreneurship from National Level Data (국가 특성이 창업활동에 미치는 영향 실증 분석)

  • Kim, Hyung Jun;Min, Tae Ki;Wang, Jingbu;Schuler, Diana;Oh, Keun Yeob
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.15 no.6
    • /
    • pp.55-65
    • /
    • 2020
  • The purpose of this study is to empirically analyze the factors that affect start-up activities at the national level. Unlike most existing research about entrepreneurship at the individual level, this empirical analysis makes use of the total early-stage entrepreneurial activity(TEA) index at national level. This was developed by the Global Entrepreneur Monitor (GEM) as the measure for the degree of entrepreneurship of the countries. Based on the previous studies, not only national income level and unemployment rate, but also other factors including the cultural characteristics of the countries were included in our regression model. Using GEM's panel data, we found that the effectiveness of the factors depends on the stage of economic development. In particular, we found 'U-shape' relationship between the level of per capita income and entrepreneurship activity by the panel regression analysis using quadratic function. This analysis result can explicitly confirm what the existing literature have explained descriptively. Furthermore, the governmental support programs are shown to have significantly positive effects on the entrepreneurship or start-up activities in the factor-driven and efficiency-driven economies. On the contrary, those programs were not very helpful in the innovative economies. Lastly, this research suggests that the 'education and training' and the 'entrepreneurial culture' be the supportive norm for new business regardless of the economic development level.

Downscaling Technique of Monthly GCM Using Daily Precipitation Generator (일 강수발생모형을 이용한 월 단위 GCM의 축소기법에 관한 연구)

  • Kyoung, Min Soo;Lee, Jung Ki;Kim, Hung Soo
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.29 no.5B
    • /
    • pp.441-452
    • /
    • 2009
  • This paper describes the evaluation technique for climate change effect on daily precipitation frequency using daily precipitation generator that can use outputs of the climate model offered by IPCC DDC. Seoul station of KMA was selected as a study site. This study developed daily precipitation generation model based on two-state markov chain model which have transition probability, scale parameter, and shape parameter of Gamma-2 distribution. Each parameters were estimated from regression analysis between mentioned parameters and monthly total precipitation. Then the regression equations were applied for computing 4 parameters equal to monthly total precipitation downscaled by K-NN to generate daily precipitation considering climate change. A2 scenario of the BCM2 model was projected based on 20c3m(20th Century climate) scenario and difference of daily rainfall frequency was added to the observed rainfall frequency. Gumbel distribution function was used as a probability density function and parameters were estimated using probability weighted moments method for frequency analysis. As a result, there is a small decrease in 2020s and rainfall frequencies of 2050s, 2080s are little bit increased.

A Study on the Determinants of Land Price in a New Town (신도시 택지개발사업지역에서 토지가격 결정요인에 관한 연구)

  • Jeong, Tae Yun
    • Korea Real Estate Review
    • /
    • v.28 no.1
    • /
    • pp.79-90
    • /
    • 2018
  • The purpose of this study was to estimate the pricing factors of residential lands in new cities by estimating the pricing model of residential lands. For this purpose, hedonic equations for each quantile of the conditional distribution of land prices were estimated using quantile regression methods and the sale price date of Jangyu New Town in Gimhae. In this study, a quantile regression method that models the relation between a set of explanatory variables and each quantile of land price was adopted. As a result, the differences in the effects of the characteristics by price quantile were confirmed. The number of years that elapsed after the completion of land construction is the quadratic effect in the model because its impact may give rise to a non-linear price pattern. Age appears to decrease the price until certain years after the construction, and increases the price afterward. In the estimation of the quantile regression, land age appears to have a statistically significant impact on land price at the traditional level, and the turning point appears to be shorter for the low quantiles than for the higher quantiles. The positive effects of the use of land for commercial and residential purposes were found to be the biggest. Land demand is preferred if there are more than two roads on the ground. In this case, the amount of sunshine will improve. It appears that the shape of a square wave is preferred to a free-looking land. This is because the square land is favorable for development. The variables of the land used for commercial and residential purposes have a greater impact on low-priced residential lands. This is because such lands tend to be mostly used for rental housing and have different characteristics from residential houses. Residential land prices have different characteristics depending on the price level, and it is necessary to consider this in the evaluation of the collateral value and the drafting of real estate policy.

Assessment of the Running Resistance of a High-speed Train Using a Coasting Test (타행 시험을 이용한 고속열차 주행저항 평가)

  • Kwon, Hyeok-Bin;Kim, Seogwon;Oh, Hyuck Keun
    • Journal of the Korean Society for Railway
    • /
    • v.17 no.3
    • /
    • pp.165-170
    • /
    • 2014
  • The resistance to motion of the Korean next-generation high-speed train (HEUM-430X) was assessed on the basis of 12 coasting test runs at coasting speeds up to approximately 380km/h. Two different methods, a linear regression method and a time-integral method, were employed to calculate decelerations from the time-velocity data and the time-distance data, respectively, and an equation of resistance to motion was devised from the deceleration data calculated at each time section. The effect of an improvement of the aerodynamic shape on the resistance to motion was investigated, with the results showing that the running resistance was reduced by about 15% due to these improvements. An increase of approximately 28% of the running resistance was also noted when running in a tunnel relative to running through an open field.

A Development of a Forecasting System of Textile Design based on Consumer Emotion(I) - Suggestion of an Efficient Textile Design Method - (소비자 감성에 기반한 텍스타일디자인 예측시스템 개발(I) - 효율적인 텍스타일디자인 방법 제안 -)

  • Cho, Hyun-Seung;Lee, Joo-Hyeon
    • Fashion & Textile Research Journal
    • /
    • v.7 no.2
    • /
    • pp.187-195
    • /
    • 2005
  • The purposes of this study were to investigate the effects of the elements of textile design on consumer emotion and to develop the emotion model which is suitable for the textile design. The descriptive system of textile design was developed based on the previous studies. Emotion measurement scale was developed to analyze the consumer emotion for the textile design. 20 representative types of textile design were collected as stimuli set for this study, consumer emotion on each design type was examined and was analyzed through the survey. For the data analysis, principal component analysis was employed. As a result, 8 emotional factors such as 'Modern', 'Fun', 'Natural', 'Elegance', 'Classic', 'Ethnic', 'Wild' and 'Sporty' were derived from the results of the survey. Emotion measurement scale which consisted of 8 factors was developed to analyze the effects of the elements of textile design on consumer emotion and 80 representative types of textile design were collected. In addition, the emotion which consumers feel for the textile design types was investigated and each textile design was described according to the descriptive system of textile design. Statistical methods of pearson correlation and multiple regression were employed to analyze the relationship between the elements of textile design and consumer emotion. The results of this study revealed that 15 design elements which affected consumer emotion were the size of motives, the shape of motives, the degree of tone contrast among motives etc. This study findings can provide specific design methods for the effectiveness of consumer emotion.

The Effects of Sociocultural Attitudes toward Appearance and Appearance Management Attitudes on Fashion Behaviors - Focused on College Students - (외모에 대한 사회문화적 태도와 외모관리 태도가 패션행동에 미치는 영향 - 대학생을 중심으로 -)

  • Park, Eun-Hee;Ku, Yang-Suk
    • Fashion & Textile Research Journal
    • /
    • v.14 no.5
    • /
    • pp.811-820
    • /
    • 2012
  • This study identifies the factor structure of sociocultural attitudes toward appearance, appearance management attitudes, fashion behaviors, and the effects of sociocultural attitudes toward appearance and appearance management attitudes on fashion behaviors. Questionnaires were administered to 255 college students living in Daegu Metropolitan City and Kyungbook province. The data collected were analyzed using frequency, factor analysis, multiple regression, and t-test. The findings were as follows. Sociocultural attitudes toward appearance were composed of two factors (body internalization and appearance recognition). Appearance management attitudes were composed of four factors (shape management recognition, weight management, appearance satisfaction, and health care). Fashion behaviors were composed of six factors (convenience, fashion following, self-satisfaction, attractiveness, pursuit of change, and pleasure). Gender of college students showed a distinction between the sub-variables of sociocultural attitudes toward appearance factors (body internalization) and appearance management attitudes (weight management) and fashion behaviors (convenience, fashion following, self-satisfaction, and pleasure). Women had more desire to have a similar looking body of TV celebrities than men. The effects of sociocultural attitudes toward appearance and appearance management attitudes on each fashion behavior variables (convenience, fashion following, self-satisfaction, attractiveness, pursuit of change, and pleasure) were explained by the factors of body internalization and appearance recognition, and weight management, appearance satisfaction, and health care. College students produced fashion appropriate to the situation. Strategies of fashion marketing based on these results are as follow. Through mass media, advertisers help university students realize a healthy outlook and create a social atmosphere that can promote healthy body attractions.

The analysis of optical influence on the grading tolerances and proportions for the round brilliant cut polished diamonds (Round brilliant cut으로 연마한 diamond의 등급별 허용 오차와 proportions에 관한 광학적 영향력 분석)

  • Kim, Eun-Ju
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.23 no.4
    • /
    • pp.173-179
    • /
    • 2013
  • Even though a rough diamond shape is irregular and rugged, it is easy to be processed to make gem, shaped facets (table, crown, pavilion and girdle) were precisely treated because they influence on the evaluation of diamond grading. Those specifications suitable for the standard round brilliant cut diamond polishing were investigated and in 95 % statistical confidence interval, standard deviation, mean and acceptable tolerance were examined. According to these variables (size, angle, depth, and thickness) distribution, the frequency analysis of ratings and proportions were compared with each other. The correlation between each variables and the evidence of influence represented in proportion were determined by the regression analysis applying LSM (Least Square Method). In this research, it was recognized that table sizes of the diamond jewels and pavilion depth (in %) influence the rating decision and in particular, the depth of pavilion acting as the main factor of proportions, also plays an important role in optical phenomena.

The structure Optimization Research of the Automation Welding Equipment of the Large L-type Using the Response Surface Method (반응표면법을 이용한 대형 L-type 자동화용접장치의 구조최적화 연구)

  • Jang, Junho;Jung, Wonjee;Lee, Dongsun;Jung, Jangsik;Jung, Sung Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.22 no.1
    • /
    • pp.138-144
    • /
    • 2013
  • The automation technology for overlay welding is needed due to the occurrence of severe corrosion and abrasion on the surface of internal contact in different shape of fittings. In Korea, different shapes of fittings have been manufactured by using the imported equipment of overlay welding automation at some companies. Thus the research on the development of overlay welding automation system (in short, OWAS) for a large L-type tube is urgently needed. In this paper, the investigation is focused on the optimal design of a supporting base for the (currently developing) OWAS of large L-type tube. Specifically we assume that the base which supports the equipment during the process of overlay welding is loaded as self-weight in the direction of gravity through static analysis especially when it is rotated 180 degree on the OWAS. For optimal design of a supporting base for OWAS of large L-type tube, Solidworks(R) (for 3-dimensional modelling) and ANASYS Workbench(R) (for structural analysis) are incorporated so as to proceed an optimization routines based on Response Surface Method (RSM) and Design of Experiment (DOE). In more specific, DOE finds out major factors (or dimensions) of the supporting base by using MINITAB(R). Then the regression equations between design variables (the major factors of supporting base) and response variables (deformation, stress and safety factor for the supporting base), which will be resulted in by RSM, verify the major factors of DOE. In the next step, Central Composite Design (CCD) plans 20 simulations of ANASYS Workbench(R) and then figures out the optimal values of design variables which will be reflected on the manufacturing of supporting base. Finally welding experiment is conducted to figure out the influence of overlay welding quality in applying the optimized design values of supporting base to the actual OWAS.

Age Determination and Estimation of Growth Parameters Using Otoliths of Small Yellow Croaker, Pseudosciaena polyactis Bleeker in Korean Waters (이석을 이용한 참조기(Pseudosciaena polyactis Bleeker)의 연령사정과 성장식 추정)

  • 이만우;장창익;이장욱
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.36 no.3
    • /
    • pp.222-233
    • /
    • 2000
  • A methodology for determining age by otolith of small yellow croaker, Pseudosoiaena polyactis Bleeker, was developed. A thin section method was chosen to be suitable for age determination because the otolith had a three-dimensional shape and thus it was not possible to read the otolith rings on the surface. The clear rings were identified on the vertical-axis cross-sectioned otoliths. The total length-total weight relationship and the growth parameters were estimated with error structure to endow with accuracy. In the relationship between total length and total weight, a multiplicative error structure was assumed because variability in growth increased as a function of the length, and the estimated equation was $W=0.0049L^{3.2153}$. The variability in growth was constant as a function of the age, revealing an additive error structure. The von Bertalanffy growth parameters were obtained from a nonlinear regression as $L_{\infty}= 37.11cm, K=0.20/yr and t_0=-1.88.$

  • PDF

BENZENE AND LEUKEMIA An Epidemiologic Risk Assessment

  • Rinsky Robert A.;Smith Alexander B.;Hornung Richard;Filloon Thomas G.;Young Ronald J.;Okun Andrea H.;Landrigan Philip J.
    • 대한예방의학회:학술대회논문집
    • /
    • 1994.02a
    • /
    • pp.651-657
    • /
    • 1994
  • To assess quantitatively the association between benzene exposure and leukemia, we examined the mortality rate of a cohort with occupational exposure to benzene. Cumulative exposure for each cohort member was estimated from historical air-sampling data and, when no sampling data existed, from interpolation on the basis of existing data. The overall standardized mortality ratio (a measure of relative risk multiplied by 100) for leukemia was 337 (95 percent confidence interval, 154 to 641), and that for multiple myeloma was 409 (95 percent confidence interval, 110 to 1047). With stratification according to levels of cumulative exposure, the standardized mortality ratios for leukemia increased from 109 to 322, 1186, and 6637 with increases in cumulative benzene exposure from less than 40 parts per million-years (ppm-years), to 40 to 199, 200 to 399, and 400 or more. respectively. A cumulative benzene exposure of 400 ppm years is equivalent to a mean annual exposure of 10 ppm over a 40-year working lifetime; 10 ppm is the currently enforceable standard in the United States for occupational exposure to benzene. To examine the shape of the exposure-response relation, we performed a conditional logistic-regression analysis, in which 10 controls were matched to each cohort member with leukemia. From this model, it can be calculated that protection from benzene induced leukemia would increase exponentially with any reduction in the permissible exposure limit.

  • PDF