• Smart Structures and Systems
• /
• 제32권1호
• /
• pp.37-47
• /
• 2023

Indirect determination of pan evaporation (PE) has been highly regarded, due to the advantages of intelligent models employed for this objective. This work pursues improving the reliability of a popular intelligent model, namely multi-layer perceptron (MLP) through surmounting its computational knots. Available climatic data of Fresno weather station (California, USA) is used for this study. In the first step, testing several most common trainers of the MLP revealed the superiority of the Levenberg-Marquardt (LM) algorithm. It, therefore, is considered as the classical training approach. Next, the optimum configurations of two metaheuristic algorithms, namely cuttlefish optimization algorithm (CFOA) and teaching-learning-based optimization (TLBO) are incorporated to optimally train the MLP. In these two models, the LM is replaced with metaheuristic strategies. Overall, the results demonstrated the high competency of the MLP (correlations above 0.997) in the presence of all three strategies. It was also observed that the TLBO enhances the learning and prediction accuracy of the classical MLP (by nearly 7.7% and 9.2%, respectively), while the CFOA performed weaker than LM. Moreover, a comparison between the efficiency of the used metaheuristic optimizers showed that the TLBO is a more time-effective technique for predicting the PE. Hence, it can serve as a promising approach for indirect PE analysis.

• 유통과학연구
• /
• 제22권8호
• /
• pp.65-76
• /
• 2024

Purpose: The study aims to recognize the relationship between big data analytics capabilities, big data analytics process, and perceived business performance from supply chain management to total customer satisfaction. Research design, data and methodology: The study followed a quantitative approach with a descriptive design. The data was collected from leading e-commerce companies in India using a structured questionnaire, and the data was coded and decoded using MS Excel, SPSS, and R language. It was further tested using Cronbach's alpha, KMO, and Bartlett's test for reliability and internal consistency. Results: The results showed that the big data analytics process acts as a robust mediator between big data analytics capabilities and perceived business performance. The 'direct, indirect and total effect of the model' and 'PLS-SEM model' showed that the big data analytics process directly impacts business performance. Conclusions: A complete indirect relationship exists between big data analytics capabilities and perceived business performance through the big data analytics process. The research contributesto e-commerce companies' understanding of the importance of big data analytics capabilities and processes.

• 한국강구조학회 논문집
• /
• 제15권4호통권65호
• /
• pp.341-358
• /
• 2003

본 논문에서는 강교의 실용적인 생애주기비용 (LCC) 최적설계를 위한 일반화된 정식화와 LCC 설계시스템 모델을 제안하였다. 강교 최적설계를 위한 LCC는 초기비용, 직접 복구 (rehabilitation) 비용과 인적 혹은 물적 손실비용의 직접비용, 도로이용자비용, 그리고 사회-경제 손실비용을 포함한 간접비용의 현재가치의 합으로 정식화하였다. 특히 본 논문에서는 교량이 속해 있는 도로의 네트워크를 고려한 도로이용자비용과 사회-경제 손실비용 산정을 위한 새로운 모델을 제안하였다. 본 연구에서 제안된 LCC 정식화 모델은 실제 강박스 거더교와 강상판형교의 LCC 최적설계 문제에 적용하였고, 다양한 경우에 대한 LCC의 효율성에 대해 비교 고찰하였다. LCC를 고려한 강교량의 최적설계는 설계시방서에 기초한 설계방법뿐만 아니라 초기비용 절감을 위한 최적설계 방법과 비교할 때 더욱 합리적이고, 경제적이며, 안전한 설계를 유도할 수 있으리라 판단된다.

• 마케팅과학연구
• /
• 제20권3호
• /
• pp.269-277
• /
• 2010

现有文献表明, 影响服务业顾客忠诚的最重要因素是服务质量. 然而, 在服务质量是直接还是间接影响顾客忠诚方面, 学者们的观点有着明显的分歧. 目前, 中国国内专门针对移动通信行业服务质量与顾客忠诚之间关系的文章较少. 此外, 以往相关文献多是将顾客忠诚作为一个整体变量进行研究, 没有进一步将其细分为多个维度. 基于此, 本文拟通过实证研究来探析移动通信业服务质量各维度与顾客忠诚各维度之间的直接和间接影响机理, 其中选择顾客满意作为二者关系的中介变量, 希望研究结论能给国内移动通信企业的服务管理提供有效的理论指导. 为了使搜集到的数据有效, 本次调研范围仅限于黑龙江哈尔滨市, 调查对象为移动通信公司的用户. 本次调研采取随机抽样的方式, 共发放问卷350份, 收回问卷325份, 回收率为 92.9%. 剔除无效问卷, 有效问卷为289份, 即有效回收率为82.6%. 本文借鉴国内外现有文献所使用的量表, 这些量表已经在实证研究中得到验证. 本文提出六个假设, 总体而言, 只有四个假设没有得到支持. 为了验证服务质量构成要素量表的合理性, 本文对289份有效样本进行探索性因子分析. 同样, 对顾客忠诚的维度进行检验. 本研究采用Cronbach's ${\alpha}$系数来评价量表的信度. 本研究从内容效度, 结构效度和聚合效度三方面对问卷进行效度检验. 本研究对数据和模型的拟合优度进行检验, 以提高假设检验的准确程度. 通过文献资料的收集, 整理及数据处理, 本文提出了服务质量五维度模型以及服务质量与顾客忠诚度之间相互关系模型, 通过实证分析验证了有形性, 可靠性, 反应性, 保证性和关怀性是服务质量的五个构成要素, 验证了PZB对于服务质量的SERVQUAL的测量方法, 研究了移动通信服务质量各维度对顾客忠诚各维度的直接影响机理, 以及服务质量各维度如何通过顾客满意这一中介变量对顾客忠诚各维度的间接影响机理, 建立了相应的关系模型,并运用结构方程分析方法,对模型进行实证检验, 得出如下研究结论: 第一, 移动通信服务质量由有形性, 可靠性, 响应性, 保证性和移情性五个要素构成, 顾客忠诚由态度忠诚和行为忠诚两个维度构成. 在PZB设计的SERVQUAL量表基础上, 本文针对移动通信行业设计了服务质量测量量表, 通过探索性因子分析得出五个因子. 这五个因子与五构成要素基本一致, 说明服务质量五要素概念适用于移动通信行业. 同样, 对顾客忠诚量表进行因子分析, 得出两个因子, 与本文中的态度忠诚和行为忠诚相一致. 第二, 移动通信服务质量对顾客忠诚存在直接和间接的正向影响作用. 其中, 服务质量对态度忠诚有直接和间接的正向作用, 间接作用是通过顾客满意这一中介变量影响的; 服务质量对行为忠诚有直接和间接的正向作用, 间接作用是通过顾客满意和态度忠诚这两个中介变量影响的. 这说明移动通信服务质量越好, 顾客的满意度越高, 其对服务提供商的态度就越积极, 在行为上就越容易表现出对服务提供商的忠诚. 而且, 服务质量各维度对顾客忠诚各维度的影响机理是不同的, 比如: 有形性对顾客满意有直接的正向作用, 但对顾客忠诚却没有显著的直接作用; 保证性对顾客满意没有显著的直接作用, 但对顾客忠诚有直接和间接的正向作用. 第三, 顾客满意在移动通信服务质量与态度忠诚, 行为忠诚之间的具有显著的中介作用, 这说明服务质量的提高可以增加顾客的满意度, 而满意的顾客更容易成为忠诚的顾客; 而态度忠诚在移动通信服务质量与行为忠诚之间的具有显著的中介作用, 这说明顾客行为上表现出忠诚可能是虚假忠诚, 只有态度和行为都忠诚的顾客才是真正的忠诚顾客. 本文的研究结论对中国及其它国家的电信运营商如何提升服务质量有一定的借鉴意义. 本文存在两方面的局限性: 首先, 本研究仅在黑龙江哈尔滨地区进行问卷调研, 针对移动公司用户, 统计数据会存在一定的抽样误差, 影响最终的统计分析结果. 第二, 本研究主要探讨了服务质量对顾客忠诚的影响关系, 并引入了顾客满意作为中介变量, 但没有考虑其他可能影响顾客忠诚的因素, 例如顾客价值, 消费者特征等.

• Asia pacific journal of information systems
• /
• 제17권2호
• /
• pp.1-28
• /
• 2007

The success of new product development is a key factor for getting competitive advantages. Marketing research has been investigating marketing capability, manufacturing technical capability, cross-functional integration, market knowledge competence, market orientation, and competitive environment as the key success factors of new product development. Recently, the role of IT infrastructure in enhancing new product advantage is assumed in the literature. However, the empirical studies on the role of IT infrastructure are lacking. The purpose of this study is to empirically exam the impacts of IT infrastructure on new product competitive advantage. In this study, IT infrastructure is conceptualized as the flexibility of IT infrastructure. Based on previous research, a conceptual model is established by incorporating the direct impact of IT infrastructure flexibility and its indirect impact through the key success factors on new product development. To empirically test the research model, data are surveyed from a pair of IS department and Marketing department of 92 consumer goods manufacturers. By employing PLS technique, the measurement reliability and reliability of research variables are tested and the path analysis is conducted to do the hypothesis testing. The path analysis shows that IT infrastructure flexibility has no direct effect on new product advantage, However, the indirect effect of IT infrastructure is found, which is mediated by marketing capability, manufacturing technical capability, cross-functional integration, and market orientation respectively. Hence, The flexible IT infrastructure increases cross-functional integration (H1), market orientation (H3), marketing capability (H5), and manufacturing technical capability (H6). All success factors of new product development excepts for competitive environment have a positive association with new product competitive advantages (from H10 to H14). Finally, the path from IT infrastructure flexibility to cross-functional integration, to market orientation, to market knowledge capability, and to new product advantage is found as the strongest path. These results indicate that the flexible IT infrastructure enhances information sharing with multiple departments and collaboration within a distributed innovation environment. The collaboration among departments positively affects the level of customer and competitor intelligence. The ability to obtain knowledge about customers and competitors makes firms to adapt to a changing environment quickly and to respond to customers' demands adequately. The flexible IT infrastructure also enhances the capability of organization to more rapidly respond to the changes in product design resulting in faster product development and reduced costs. In addition to, it enhances marketing capability by the two-way communications with customers and the analyses of various kinds of customer data. In brief, the finding of this study suggests that the flexible IT infrastructure allows many firms to pursue sustained new product competitive advantages. This study advances research on IT infrastructure in two important aspects. First, by Integrating marketing research and IS research, this study develops a conceptual model on the role of IT infrastructure in enhancing new product advantage. Second, it empirically finds the indirect impacts of IT infrastructure on new product advantage, which confirms the potential for the IS field to contribute to new product development research. The limitations of this study are also discussed to provide research directions for future research.

• 말소리와 음성과학
• /
• 제10권1호
• /
• pp.75-81
• /
• 2018

Diplophonia is generally defined as the perception of more than one fundamental frequency component in a voice. Its perceptual aspect has traditionally been used to evaluate diplophonia because the perceptions can be easily evaluated, but there are limitations in the validity of the reliability of the intra- and inter-raters, examination situation, and variation of voice sample. Therefore, the purpose of this study is to confirm the reliability and accuracy of auditory perceptual evaluation by comparing non-invasive indirect assessment methods (sound waveform and EGG analysis), and to identify their usefulness with diplophonia. A total of 28 diplophonic voices and 39 non-periodic voices were assessed. Three raters assessed the diplophonia by performing an auditory perception evaluation and identifying the quasi-periodic perturbations of the acoustic waveform and EGG. Among the three discrimination methods, intra- and inter-rater reliability, sensitivity, specificity, accuracy, positive likelihood ratio, and negative likelihood ratio were examined, and the McNemar test was performed to compare the discriminant agreement. The accuracy of the auditory perceptual evaluation (86.57%) was not significantly different from that of sound waveform acoustic (88.06%), but it was significantly different from that of EGG (83.33%). The reading time (6.02 s) for the auditory perceptual evaluation was significantly different from that for sound waveform analysis (30.15 s) and EGG analysis (16.41 s). In the discrimination of diplophonia, auditory perceptual evaluation has sufficient reliability and accuracy as compared to sound waveform and EGG. Since immediate feedback is possible, auditory perceptual evaluation is more convenient. Therefore, it can continue to be used as a tool to discriminate diplophonia in clinical practice.

• KEPCO Journal on Electric Power and Energy
• /
• 제4권1호
• /
• pp.19-24
• /
• 2018

가스터빈 동익에 대한 지속적인 국산화 개발이 추진되어, 국내 정밀 주조 기술을 향상시키고, 동익의 유지 보수 비용을 낮추는 등의 직간접적인 긍정적 효과를 가져왔지만, 여전히 국산화 개발품이 발전소에서 안정적인 실사용이 가능한지에 대한 우려가 존재한다. 향상된 소재와 주조기술을 바탕으로 조직학적, 기계적 성질에서 충분한 품질을 확보하였더라도, 개발품을 대상으로 다양한 신뢰성 검증이 요구되는 이유이다. 고속회전시험기는 로터, 디스크 등의 회전체에 원심력을 가하여, 이에 따른 제품의 특성을 분석하기 위한 시험장비로 일반적으로 과속도시험을 통한 최종적인 품질검사에 주로 사용된다. 본 논문에서는 전력연구원에 구축된 고속회전시험기를 활용한 가스터빈 동익에 대한 과속도시험을 포함한 저주기피로시험 사례를 중심으로 신뢰성 시험 및 평가 결과를 기술하였다.

• Journal of Preventive Medicine and Public Health
• /
• 제43권2호
• /
• pp.174-184
• /
• 2010

Objectives: This study shows the issues that should be considered when applying standardized rates using Community Health Survey(CHS) data. Methods: We analyzed 2008 CHS data. In order to obtain the reliability of standardized rates, we calculated z-score and rank correlation coefficients between direct standardized rate and indirect standardized rate for 31 major indices. Especially, we assessed the change of correlations according to population composition (age and sex), and characteristics of the index. We used Mantel-Haenszel chi-square to quantify the difference of population composition. Results: Among 31 major indices, 29 indices' z-score and rank correlation coefficients were over 0.9. However, regions with larger differences in population composition showed lower reliability. Low reliability was also observed for the indices specific to subgroups with small denominator such as 'permanent lesion from stroke', and the index with large regional variations in age-related differences such as 'obtaining health examinations'. Conclusions: Standardized rates may have low reliability, if comparison is made between areas with extremely large differences in population composition, or for indicies with large regional variations in age-related differences. Therefore, the special features of standardized rates should be considered when health state are compared among areas.

• 임상간호연구
• /
• 제28권2호
• /
• pp.185-197
• /
• 2022

Purpose: This study was performed to verify reliability and validity of the Korean Pediatric Patient Classification System (KPPCS) and estimate nursing time conversion index. Methods: The study was conducted in 9 children's hospital which included various areas and size of bed settings. To verify intraclass correlation reliability and construct validity, staff nurses and nurse managers of 21 wards classified 575 patients according to KPPCS comparing differences by age, days of stay, type of stay and medical department. Direct and indirect nursing time of 575 patients were measured by 284 nursing staffs by stopwatch observation and self reports for 24 hours. Results: KPPCS has 12 categories, 55 nursing activities and 80 criterions. High agreement among nurses (r=.91, p<.001) suggested substantial reliability. Construct validity was verified by comparing differences in age, days of stay, type of stay and medical department (p<.05). The correlation of nursing time and classification score was also statistically significant (r=.59, p<.001). The nursing time conversion index was 10.78 minutes per 1 classification score. The entire patient group were classified to four groups using KPPCS. Conclusion: The findings suggest that KPPCS would be a useful tool for estimating nursing demands related to the complexity of pediatric patients.

• 대한토목학회논문집
• /
• 제26권1A호
• /
• pp.75-89
• /
• 2006

본 논문에서는 생애주기동안 발생하는 부식이나 일평균교통량 및 중차량의 통행량와 같은 사용환경에 의존하는 강교의 생애신뢰성에 기초한 생애주기비용(Life-Cycle Cost: 이하 LCC) 최적설계 방법론을 제안하였다. 강교 최적설계를 위한 LCC는 초기비용, 생애주기 기대유지관리비용, 생애주기 기대직접복구비용과 인적 혹은 물적손실비용, 도로이용자비용, 그리고 사회-경제 손실비용을 포함하는 간접복구비용을 현재가치의 합으로 정식화하였다. 이러한 LCC비용항목 중에서 생애주기 복구비용의 산정을 위해서는 하중과 저항이력에 의존하는 누적손상확률로부터 산정되는 연파손확률이 고려되어야한다. 이를 위해 본 논문에서는 Nowak의 활하중 모델(1993)과 부식개시, 부식률, 그리고 재도장영향을 고려한 수정된 부식모델을 제안하였다. 이와같이 본 연구에서 제안된 LCC 최적설계 방법론은 3 경간연속(40 m+50 m+40 m=130 m)의 실제 강박스거더교에 적용되었고, 강재종류, 부식환경, 교통량 및 할인율에 따른 LCC의 효율성에 대해 비교 고찰하였다. 적용예를 통해 부식환경, 일평균교통량, 그리고 중차량의 통행량, 할인율 등은 강교 LCC최적설계에 매우 중요한 영향을 미칠 수 있음을 알 수 있었으며, 이러한 교량의 사용환경인자들은 경우에 따라 LCC 최적설계에 대한 주요 변수로 고려되어야 할 것으로 판단된다.