• 한국경영과학회지
• /
• 제38권1호
• /
• pp.45-59
• /
• 2013

A long-term forecasting method for a new product in early stage of diffusion is proposed. The method includes a constrained non-linear least square estimation with the logistic diffusion model. The constraints would be critical market informations such as market potential, peak point, and take-off. Findings on 20 cases having almost full life cycle are that (i) combining any market information improves the forecasting accuracy, (ii) market potential is the most stable information, and (iii) peak point and take-off information have negative effect in case of overestimation.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권10호
• /
• pp.675-685
• /
• 2020

The main purpose of this study is to investigate the potential effect of ownership concentration on the relationship between board composition and bank performance. The study employs a sample of Saudi banks listed on Saudi stock exchange (TADAUWL) over the period from 2011 to 2018. To test the study hypotheses and control for endogeneity issues, the Ordinary Least Square (OLS) and the Two-Stage Least Squares (2SLS) techniques are used. The empirical results reveal a significant negative moderating effect of ownership concentration on the association between board composition and bank performance, which confirms the study argument and supports hypotheses. The results indicate that board composition in terms of independent board members, executive board members, and non-executive board members in banks with higher ownership concentration have a weaker positive influence on bank performance. For control variables, the results are almost consistent with theoretical perspectives and previous empirical evidence. The results of this study have important implications for regulatory authorities, companies, and market participants in Saudi Arabia and countries with high concentrated ownership to understand how ownership concentration could affect corporate governance and firm performance and to identify appropriate actions to protect board composition from the influence of ownership concentration.

• 전자공학회논문지
• /
• 제51권5호
• /
• pp.177-187
• /
• 2014

본 논문에서는 고속 부공간 추적 기법인 FAPI (Fast Approsimated Power Iteration)에 GVFF RLS (Gradient-based Variable Forgetting Factor Recursive Least Square Error)를 적용한 GVFF FAPI 를 제안한다. 기존의 FAPI는 신호의 공분산 행렬을 추정하기 위해 고정 망각 인자를 사용하기에, 부공간이 지속적으로 변하는 비정재 환경에 적용하기 여려운 단점이 있다. 이러한 문제점을 해결하기 위해, GVFF FAPI는 개선된 MSE (Mean Square Error)의 분석으로부터 유도된 MSE의 기울기 기반의 시변 망각 인자를 사용한다. 또한 GVFF RLS의 망각 인자 업데이트 식을 개선하여 부공간이 지속적으로 변하는 비정재 환경에서 부공간 에러를 줄인다. 개선된 망각 인자 업데이트 식은 MSE의 기울기가 양수이면 망각 인자를 빠르게 감소하게 하고 MSE의 기울기가 음수이면 망각 인자를 천천히 증가시킨다. 모의실험을 통해서 도래각이 지속적으로 변하는 환경에서 GVFF FAPI 알고리즘이 기존의 FAPI 알고리즘보다 작은 부공간 에러를 가지는 것을 보이고, 추적된 부공간을 도래각 추정기법에 적용하였을 때 추적된 도래각의 RMSE (Root Mean Square Error)가 더 작은 것을 확인한다.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권5호
• /
• pp.1099-1107
• /
• 2021

This study focuses on green human resources management (GHRM), which is currently a strategic issue in almost every service or manufacturing company, including courier service SMEs in Indonesia. This study intends to analyze the relationship between GHRM and supply chain organizational learning (SCOL), supply chain performance (SCP), and business performance (BP) still rarely studied. The population encompasses all courier service SMEs in the Special Province of Yogyakarta (DIY) and East Java, Indonesia. The study targets courier service SMEs that meet certain conditions; 130 SMEs responded from the target of 200 SMEs. Partial Least Square statistical technique is used. The results show that conventional HRM practices are increasingly being abandoned by courier companies in Indonesia, particularly in Special Province of Yogyakarta and East Java. Although GHRM has a negative and non-significant effect on BP, GHRM has a positive effect on SCOL and SCP. SCOL has a significant positive effect on SCP and BP. Furthermore, SCOL mediates the relationship between GHRM and SCP and SCOL mediates the relationship between GHRM and BP. Likewise, SCP has a positive effect on BP. In addition, SCP mediates the relationship between GHRM and BP. SCP also mediates the relationship between SCOL and BP.

• Nuclear Engineering and Technology
• /
• 제55권3호
• /
• pp.1052-1060
• /
• 2023

The airborne radiation monitoring has been used in geophysics for more than forty years and now it also has its important role in emergency monitoring. The aircraft background and the cosmic gamma-rays contribute to the measured gamma spectrum on the aircraft board. This adverse effect should be eliminated before the data processing. The paper describes two semiparametric methods to estimate the full spectrum aircraft background and cosmic gamma-ray contribution from spectra measured at altitudes where terrestrial contribution is negligible. The methods only assume to know possible peak positions in spectra and their full width at half maximum, that can be easily obtained e.g. from terrestrial measurement. The methods were applied to real experimental data acquired on Mi-17 and Bell 412 helicopter boards. The IRIS airborne gamma-ray spectrometer, with 4×4 L NaI(Tl) crystals, produced by Pico Envirotec Inc., Canada, was used on helicopters' boards. To obtain valid estimate of the aircraft background and the cosmic contribution, the measurements over sea and large water areas were carried out. However, the satisfactory results over inland were also achieved comparing with those acquired over large water areas.

• 지능정보연구
• /
• 제29권4호
• /
• pp.111-127
• /
• 2023

본 연구는ChatGPT 사용의 사용자 인식에 대한 연구로, 사용자 정책기대와 사용자 혁신성이 ChatGPT 기술수용과 사용의도에 미치는 영향 관계를 TRA(Theory of Reasoned Action) 등의 변수들을 활용하여 분석하는 것을 목표로 하였다. 정책기대, 사용자 혁신성이 유용성과 쾌락적 동기를 매개하여서 사용의도에 미치는 영향과 주관적 규범이 유용성과 사용의도에 미치는 영향을 연령변수를 이용하여서 MZ세대와 비 MZ세대로 구분하여 분석하였으며, 연령별 차이가 정책기대와 상호작용하여서 유용성에 미치는 영향에 조절효과가 있는지 검증하였다. PLS(Partial Least Square) 구조 방정식과 SPSS Package를 이용하여 ChatGPT사용자 300명을 대상으로 Online 설문을 실시하고, PLS와 SPSS을 통해 통계 분석을 수행하였다. 분석 결과에 따르면, 초기 사용자의 혁신성이 높을수록 ChatGPT 사용의도가 높아진다는 것을 확인하였다. 그리고, MZ세대와 비MZ세대의 차이를 비교한 조절효과분석에서는 정책기대가 ChatGPT사용의 유용성에 부(-)의 영향을 미치는 효과를 보였다.

• 보건행정학회지
• /
• 제25권3호
• /
• pp.240-251
• /
• 2015

Background: Dentist's income is quite variable. We investigate the factors underlying the distribution of dental revenue and dentist income. Methods: Financial and structural variables of private dental practices(N=13,967) were examined with 2010 Economic Census microdata which include non-insurance revenue. We conducted quantile regression method(QRM) and ordinary least square(OLS) in treating skewness and heteroskedasticity of distributions. The effective estimation for the upper and lower range of distribution becomes possible by QRM. Results: Mid-career dentists are shown to have higher revenue and income. Male dentists achieve the higher revenue and income than female dentists in all quantiles. Group practices show lower income per owner than solo practices significantly. The revenue and income are increased with increasing size of clinics. The high cost in renting the clinic office is found to have a big positive effect on the revenue but a little positive effect on the income. Interestingly the density of dentists shows negative effect on the lowest quantile of the revenue but positive effect on the highest quantile. The lowest quantile of the revenue in the capital areas have the relatively high revenue. The lowest quantile of the income in metropolitan city show higher income than those in other areas significantly. Conclusion: The suggested QRM is shown to have more effective and efficient tool in finding out determinants of dentists' revenue and income of our concern. The results of this study are expected to be employed for dentists preparing for the opening practices in their organizational settings and locational selections. The distributional efficiency of dental human resources could be accomplished if policy makers guide dentists with this knowledge.