• International Journal of Computer Science & Network Security
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• v.21 no.7
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• pp.211-220
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• 2021

The aim of the study is to implement a factor analysis of the determinants of pricing in a state-regulated competitive market using economic and mathematical modelling methods and to develop ways to improve the pricing environment of the market under study. The purpose of the work defines the main objectives: (i) to investigate the features of the competitive model of the Ukrainian flour market; (ii) to analyse the current price conjuncture of the flour market and the dynamics of the main determinants of pricing; (iii)to develop ways of improving the price situation on the flour market on the basis of the factor analysis on the results of economic and mathematical modelling. In order to ensure the reliability and validity of the research results, the following methods were applied: the logical-dialectical method of scientific knowledge in the study of the main theoretical aspects of flour market functioning, the method of logical generalisation and synthesis, comparison, factor analysis, correlation and regression analysis, the graphical method, etc. It has been shown that pricing in a state-regulated competitive market has its own characteristics. For example, in the flour market the price of goods cannot be influenced by producers (sellers) by any methods, therefore determinants of pricing by indirect influence have been taken into account. The five-factor power model of wheat flour price has been constructed. It was substantiated that the price of wheat flour in Ukraine is mostly influenced by consumer price index (0.92 %). The received complex model of wheat flour price may be used also for medium-term forecasting and working out the ways of price formation optimization in the flour market.

• Structural Engineering and Mechanics
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• v.81 no.5
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• pp.565-574
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• 2022

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (𝚫K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (𝚫K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation's Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

• International Journal of Knowledge Content Development & Technology
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• v.13 no.2
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• pp.7-22
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• 2023

The development of rural areas is expected to be holistic covering all essential infrastructure. Community information centres (CICs) are agen- cies that should be part of the infrastructures for rural development. Unfortunately, these centres are hardly seen in rural communities in Nigeria, including Afikpo in Ebonyi State. Thus, this study was conceived to explore the perceptions of citizens towards the establishment of CICs in the locality. It adopted survey research method with questionnaire as instrument for data collection, which was self-developed and validated by experts with a pre-texted reliability index of 0.72. A total of 399 copies of the questionnaire were distributed, out of which 267 copies were properly completed, representing 67% and were used for analysis. Findings revealed that the citizens have overall positive perception to- wards establishing the CICs; they are also knowledgeable of the benefits of such centres. Furthermore, there are workable suggestions on ways of establishing, funding and managing CICs in Afikpo. In addition, about 65% of the respondents indicated interest to assist and support the funding and management of the CICs when established. However, the challenges of inadequate funding and support as well as the possible politics of where to site/locate the CICs in Afikpo, are likely impediments to the project. The study concluded that citizens have strong and positive disposition towards establishing CICs in Afikpo. The implications of such CICs for technological innovations were analysed. The study recom- mends, among others, that government should see the establishment of CICs as priority projects that would significantly contribute to the growth and development of rural communities in Nigeria; communities in Afikpo should explore self-help approach to development; and political representatives from Afikpo should take advantage of establishing CICs as constituency projects for the citizens.

• Journal of the Korea Society of Computer and Information
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• v.14 no.9
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• pp.167-177
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• 2009

As the service quality has been reconsidered in public sector as well as private enterprises, the need for public sectors to adopt principle and practices of private sectors is concerned with customer-focused approach, the different business culture of public service organizations makes it difficult to improve service qualify. Also, Since concept of service contains intangibility, heterogeneity, Simultaneousness and perishability, it makes peoples more difficult to measure service quality. Therefore, this study proposes synthetic Administrative Service duality Index(ASQI) using fuzzy set theory and analytic hierarchy process to evaluate the service qualify in subjective environment. In ASQI model, Fuzzy set theory helps to measure the ambiguity of concepts that are relative to human being's subjective judgement. Also, this study utilizes AHP method to evaluate the preference weights of service quality dimensions (tangibility, reliability, responsiveness, assurance, empathy) for customers.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.43-43
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• 2020

보령댐은 충남 서부지역 8개 시·군에 생활용수와 공업용수를 공급하고 있는 중요한 수원으로 최근 우리나라에서 발생한 연속적인 가뭄으로 2015년에는 저수율이 7.5 %까지 감소하여 제한급수가 시행되었다. 본 연구에서는 가뭄으로 인한 물 공급 부족에 취약함을 보인 보령댐 유역(297.4 ㎢)을 대상으로 SWAT(Soil and Water Assessment Tool) 모델과 RCP(Representative Concentration Pathways) 시나리오를 활용하여 극한 기후변화 사상이 반영된 보령댐의 내한능력을 평가하였다. SWAT 모형을 활용하여 보령댐의 물수지를 모의하기 위하여 보령댐의 실측 유출량, 저수량, 방류량으로 보령댐 유입량과 저수량을 보정(2002~2004) 및 검정(2005~2007)하였으며, 실측 저수량을 기반으로 미래 댐 운영을 모의하였다. 검·보정 결과, 댐 유입량과 저수량의 PBIAS(%)는 -0.04, -0.09, NSE(Nash and Sutcliffe Efficiency)는 0.52, 0.96, RMSE(Root Mean Square Error)는 1.80 mm/day, 0.67 × 10⁶㎥로 분석되어 신뢰성 있는 모의 결과를 보였다. 보정된 SWAT 모형으로 가뭄 사상이 반영된 기후변화를 모의하기 위하여 APCC의 26개 CMIP5 GCM 시나리오를 SPI (Standardized Precipitation Index)와 연속 이론(Runs theory)으로 분석하여 6개의 극한 가뭄 시나리오 (RCP 4.5, 8.5 CMCC-CM, INM-CM4, IPSL-CM5A-MR)를 선정하였으며, 선정된 시나리오를 모형에 적용하여 가뭄 사상을 반영한 보령댐의 미래 내한능력을 평가하였다. 내한능력평가 및 분석 기간은 Historical(1980~1999; 1990s), Present(2000~2019; 2010s), 그리고 미래 기간 (2020~2039; 2030s, 2040~2059; 2050s, 2060~2079; 2070s, 2080~2099; 2090s)으로 나누었으며, 취약성(Reliability), 회복성(Resilience), 위험성(Vulnerability), 세 가지 지표로 내한능력 평가를 수행하였다. 평가 결과, 미래 취약성은 2050s IPSL-CM5A-MR 시나리오에서 0.803까지 감소하였으며, 회복성과 위험성은 2070s IPSL-CM5A-MR 시나리오에서 0.003, 3,567.6 × 10⁶㎥까지 감소하였다.

• Restorative Dentistry and Endodontics
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• v.46 no.2
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• pp.23.1-23.11
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• 2021

Objectives: This study assessed the reliability of digital color measurements using images of resin composite specimens captured with a cellphone. Materials and Methods: The reference color of cylindrical specimens built-up with the use of resin composite (shades A1, A2, A3, and A4) was measured with a portable spectrophotometer (CIELab). Images of the specimens were obtained individually or pairwise (compared shades in the same photograph) under standardized parameters. The color of the specimens was measured in the images using RGB system and converted to CIELab system using image processing software. Whiteness index (WI_D) and color differences (ΔE₀₀) were calculated for each color measurement method. For the cellphone, the ΔE₀₀ was calculated between the pairs of shades in separate images and in the same image. Data were analyzed using 2-way repeated-measures analysis of variance (α = 0.05). Linear regression models were used to predict the reference ΔE₀₀ values of those calculated using color measured in the images. Results: Images captured with the cellphone resulted in different WI_D values from the spectrophotometer only for shades A3 and A4. No difference to the reference ΔE₀₀ was observed when individual images were used. In general, a similar ranking of ΔE₀₀ among resin composite shades was observed for all methods. Stronger correlation coefficients with the reference ΔE₀₀ were observed using individual than pairwise images. Conclusions: This study showed that the use of cellphone images to measure the color difference seems to be a feasible alternative providing outcomes similar to those obtained with the spectrophotometer.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5C
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• pp.343-350
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• 2006

The resistance bias factors for driven steel pipe piles are evaluated as a part of study to develop the LRFD(Load and Resistance Factor Design) for foundation structures in Korea. The 43 data sets of static load tests and soil property tests performed in the whole domestic area were collected and analyzed to determine the representative bearing capacities of the piles using various methods. Based on the statistical analysis of the data, the Davisson's criterion is proved to be the most reasonable method for estimation of pile bearing capacity among the methods used. The static bearing capacity formulas and the Meyerhof method using N values are applied to calculate the design bearing capacity of the piles. The resistance bias factors of the driven steel pipe piles are evaluated respectively as 0.98 and 1.46 by comparison of the bearing capacities for both of the static bearing capacity formulas and the Meyerhof method. It is also shown that uncertainty of the static bearing capacity formulas is relatively less than that of the Meyerhof method.

• Archives of Plastic Surgery
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• v.50 no.5
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• pp.452-462
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• 2023

This scoping review aimed to identify and categorize the available measurement options for vaginal laxity (VL), their indications of use, and whether these measurements can sufficiently provide objective clinical judgment for cases indicated for vaginal rejuvenation with many treatment options nowadays. Systematic searches were conducted on five electronic databases, manually searching articles' bibliographies and predetermined key journals with no date or study design limitations. We included all studies involving VL in their inclusion criteria, treatment indications, and outcome parameters. We used the Arksey and O'Malley frameworks as the guideline in writing this scoping review. Of the 9,464 articles identified, 66 articles and 11,258 subjects were included in the final analysis. The majority of studies were conducted in obstetrics and gynecology (73%), followed by plastic surgery (10%), medical rehabilitation (4.5%), dermatology (4.5%), and others (8%). Most studies originated from the North American region (30%). The following measurement tools were used: (1) interviews, (2) questionnaires, (3) physical/digital examinations, (4) perineometers, and (5) others. Our results suggested that subjective perception of laxity confirmed by directed interview or questionnaire is sufficient to confirm VL. Additional evaluation of pelvic floor muscle through digital examination or perineometer or other preferred tools and evaluation of sexual function through validated questionnaire (Female Sexual Function Index, Female Sexual Distress Scale-Revised, etc.) should follow to ensure holistic care to patients. Future research on the psychometric properties (reliability and validity) of commonly used measurements and the correlation in between subjective and objective measurements should be initiated before their clinical applications.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.2
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• pp.112-124
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• 2023

Objectives: Obesity is a chronic metabolic disease that negatively affects quality of life and health. It is associated with various disease and its prevalence is on the rise. Although various treatments for obesity are used, they have several adverse effects. Pharmacoacupuncture is a widely used method for treating various diseases and has the advantage of having fewer adverse effects. This systematic review and meta-analysis evaluate the efficacy of pharmacoacupuncture in treating obesity. Methods: Eight electronic databases were searched from their inception to August 2023. Only randomized controlled trials were included in this review. Intervention groups included pharmacoacupuncture. Control groups had no limitation. The primary outcome was body mass index (BMI), and the secondary outcomes were body weight (BW), waist circumference (WC), and adverse effects. Continuous outcome data were presented as mean differences (MD) with 95% confidence intervals (CI). Results: Four randomized controlled trials (RCTs) involving 139 participants were included in this systematic review and meta-analysis. Results revealed that BMI ((MD)=-0.98, 95% CI -1.84 to -0.11, Z=2.22, P=0.03, I²=0%), WC (MD=-4.29, 95% CI -7.51 to -1.08, Z=2.62, P=0.009, I²=38%) were significantly improved in the intervention groups compared to control groups. Adverse effects were reported in two studies. Conclusions: This systematic review and meta-analysis suggests that pharmacoacupuncture is an effective and safe therapy for simple obesity. Further detailed studies should be conducted on effects of pharmacoacupuncture for obesity to increase reliability.

• Safety and Health at Work
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• v.14 no.4
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• pp.358-367
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• 2023

Background: This study aimed to develop and assess the psychometric features of the Physical Activity at Workplace Questionnaire (PAWPQ) based on the Social Cognitive Theory (SCT) to evaluate employees' physical activity (PA) behaviors at the workplace. Methods: This psychometric cross-sectional study was conducted on 455 employees working in one of the gas refineries in Iran. The participants were selected using the proportional stratified sampling method in 2019. The data collection tools were a demographic information questionnaire, the short form of the International Physical Activity Questionnaire (IPAQ), and a questionnaire developed based on the SCT, whose psychometric features were confirmed in terms of validity and reliability. Data were analyzed using SPSS₂₂ and AMOS₂₀ software. Results: The first version of PAWPQ-SCT had 74 items. After evaluating content and face validity, nine items were removed. The results of the content validity index (0.98), content validity ratio (0.86), and impact score (3.62) were acceptable for the whole instrument. In exploratory factor analysis, after removing seven items-58-item final version of the scale-six factors could explain 73.54% of the total variance. The results of structural equation modeling showed the acceptable fit of the model into the data (RMSEA = 0.052, CFI = 0.917, NFI = 0.878, TLI = 0.905, IFI = 0.917, CMIN/DF = 2.818). Cronbach's alpha coefficient and Intraclass Correlation were 0.90 and 0.86, respectively. Conclusion: This study confirmed that the psychometric features of the 58-item final version of PAWPQSCT constructs were acceptable in a sample of Iranian employees. This questionnaire can be used as a valid and reliable tool to evaluate Iranian employees' PA behaviors and develop effective educational interventions for workers and managers.