• The Journal of Advanced Prosthodontics
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• 제14권5호
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• pp.294-304
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• 2022

PURPOSE. The purpose of this study was to evaluate the influence of different palatal vault configurations on the accuracy and scan speed of intraoral scans (IO) of completely edentulous arches. MATERIALS AND METHODS. Three different virtual models of a completely edentulous maxillary arch with different palatal vault heights- Cl I moderate (U-shaped), Cl II deep (steep) and Cl III shallow (flat)-were digitally designed using CAD software (Meshmixer; Autodesk, USA) and 3D-printed using SLA-based 3D-printer (XFAB; DWS, Italy) (n = 30; 10 specimens per group). Each model was scanned using intraoral scanner (Trios 3; 3Shape^TM, Denmark). Scanning time was recorded for all samples. Scanning accuracy (trueness and precision) were evaluated using digital subtraction technique using Geomagic Control X v2020 (Geomagic; 3DSystems, USA). One-way analysis of variance (ANOVA) test was used to detect differences in scanning time, trueness and precision among the test groups. Statistical significance was set at α = .05. RESULTS. The scan process could not be completed for Class II group and manufacturer's recommended technique had to be modified. ANOVA revealed no statistically significant difference in trueness and precision values among the test groups (P=.959 and P=.658, respectively). Deep palatal vault (Cl II) showed significantly longer scan time compared to Cl I and III. CONCLUSION. The selection of scan protocol in complex cases such as deep palatal vault is of utmost importance. The modified, adopted longer path scan protocol of deep vault cases resulted in increased scan time when compared to the other two groups.

• 디지털콘텐츠학회 논문지
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• 제18권2호
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• pp.347-356
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• 2017

희소 표현을 이용한 얼굴 인식 방법론은 강인성이 입증된 우수한 얼굴 인식 방법으로 알려져 있다. 이 방법론의 단점은 $L_1$-노름 최적화 문제를 통해 희소해를 구하는 과정에서 많은 시간이 소요되어 실시간 응용 분야에 적합하지 않다는 것이다. 통상적인 $L_2$-노름 최적화 문제를 통해 얻어진 희소해는 희소성이 결여되고 정확도가 떨어져서 희소 표현을 이용한 인식 방법론에는 사용되고 있지 않다. 우리는 본 논문에서는 탐욕적인 방식으로 $L_2$-노름 최적화 문제를 푸는 ROMP 방식을 도입해 희소해를 구하는 방법을 제안하고, 실험을 통해 제안한 방식이 정확도에서 기존 방식과 유사하며 속도는 60배 이상 빠름을 보였다. 또한, 희소 표현기반인식 방법론으로 희소해의 분포만을 고려하여 분류하는 단순한 방식인 C-SCI 방법론을 제안하였다. 이 방법론은 테스트 데이터를 복원하는 기존 방식과 성능 면에서는 유사하나 속도 면에서는 약 5배 빠름을 실험적으로 입증하였고, 이론적인 복잡도 분석 결과도 제시하였다.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.279-291
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• 2020

This study aims to develop the concept of innovation models with the marketing channel construct approach, marketing innovation, product segmentation, and customer insight; as well as improvements to the theory of resource-based combined with the method of service-dominant logic. This study approach is based on quantitative descriptive conducted with three stages of testing scenarios. The first test is the mapping of the innovation model construct through testing the validity and reliability with the moderation of customer orientation variables. The second scenario examines the relationship of influence between the independent variables on the dependent variable of 29 hypothetical analysis equation modeling. The unit of analysis was conducted on 497 SMEs involved in the food and beverage sectors, with the criteria being SMEs must have a rating of 4-5 points on the Go-Food applications software. The results shown that: 1) the construct used to develop an innovative model both directly and via moderation is positive and significant; 2) Through a complicated relationship that involves all components of the variable, it outlines a positive and significant effect except for the path of analysis (μ5). The theoretical and managerial implications state that the service-dominant logic approach and resource-based view theory have extreme reliability and interrelations.

• 한국소음진동공학회논문집
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• 제22권6호
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• pp.574-581
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• 2012

Condition-based maintenance(CBM) has been used as a useful concept for optimizing maintenance plan and decreasing maintenance cost in several kinds of plant sites. This study introduced an example that developed an integrated management system for maintenance parameters and hydraulic turbine of hydro-power plant in order to improve its maintenance strategy as applying CBM techinique. The integrated management system consists of three parts. One is a hardware part including PDA inspection system and several kind of precision measuring instruments. Another is a vibration monitoring system on hydraulic turbine. The other is a software part that takes charge of making hierarchy tree of maintenance parameters and their inspection route, managing accumulated database, assessing health condition of components, and supporting interface with other enterprise management system. The system has been installed at Chuncheon hydro-power plant for test and demonstration. It is expected that the system can contribute database construction for diagnostics and prognostics on facility health condition and systematic accumulation of know-how on operation and maintenance of plant.

• The Journal of Asian Finance, Economics and Business
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• 제8권9호
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• pp.333-340
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• 2021

In Vietnam, the desire to consume organic vegetables is increasing as people become increasingly concerned about foods that contain several chemicals and toxins that are hazardous to their health. However, numerous subjective and objective factors continue to influence customers' purchase intention and behavior, indicating that this market has not yet reached its full potential. The study analyzes the impacts of trust, price, and convenience on consumers' consumption behavior and frequency of using organic vegetables in Northern Vietnam. We surveyed 312 consumers in the region. After classifying the data, 178 participants have used or regularly used organic vegetables selected for further study. Next, the author applied SmartPLS software with version 3.3 to test the hypotheses and analyze the effects of the observations. The result shows that three main factors affect customers' organic vegetable consumption behavior, especially perceived convenience. This study contributes to the development of comprehensive policy mechanisms and regulations on product traceability. Furthermore, market management authorities must have a strategy in place to inspect the product quality of organic vegetable store chains regularly to build customer trust and support the growth of organic vegetable production and supply chains in Vietnam's northern region.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.452-472
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• 2019

Most existing wavelet-based multiplicative watermarking methods are affected by geometric attacks to a certain extent. A serious limitation of wavelet-based multiplicative watermarking is its sensitivity to rotation, scaling, and translation. In this study, we propose an image watermarking method by using dual-tree complex wavelet transform with a multi-objective optimization approach. We embed the watermark information into an image region with a high entropy value via a multiplicative strategy. The major contribution of this work is that the trade-off between imperceptibility and robustness is simply solved by using the multi-objective optimization approach, which applies the watermark error probability and an image quality metric to establish a multi-objective optimization function. In this manner, the optimal embedding factor obtained by solving the multi-objective function effectively controls watermark strength. For watermark decoding, we adopt a maximum likelihood decision criterion. Finally, we evaluate the performance of the proposed method by conducting simulations on benchmark test images. Experiment results demonstrate the imperceptibility of the proposed method and its robustness against various attacks, including additive white Gaussian noise, JPEG compression, scaling, rotation, and combined attacks.

• 한국정보과학회논문지:소프트웨어및응용
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• 제28권9호
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• pp.669-680
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• 2001

유전자 알고리즘(GA:Genetic Algorithm)은 최적화 문제를 풀기 위해 생물학적 진화(evolution) 과정을 모방한 최적화 알고리즘이다. 유전자 알고리즘은 복잡한 상태 공간에서 최적 해를 찾기 위해 전통적인 최적화 기법과는 달리 유향적 임의 탐색을 행한다. 학습에 해당하는 국부 탐색(local search)을 유전적 알고리즘은 exploration 탐색과 exploitation 탐색의 균형을 유지시켜 줄 수 있는 한 방법이다. 모집단 내의 각 개체가 진화 과정 중에 학습한 유전적 특질들은 그 다음 세대에서 되물림 되며 이러한 학습(learning) 과정을 유전자 알고리즘과 결합시킴으로써 탐색 속도의 향상을 기대할 수 있다. 이 논문에서는 함수 최적화를 위해 속도를 개선한 셀룰러 학습을 기반으로 하는 유전자 알고리즘을 제안한다. 제안하는 셀룰러 학습 전략은 셀룰러 오토마타의 주기성과 수렴성을 기반으로 하며, 유기체가 그 개체의 생명 주기의 한 세대에서 얻게되는 지식과 경험들을 자손에게 전달한다는 이론을 바탕으로 한다. 제안한 셀룰러 학습 전략의 효율을 기존의 복합 유전자 알고리즘에서의 라마키안 진화 및 볼드윈 효과와 비교하였다. 다양한 테스트 베드 함수에 대한 실험을 통하여 셀룰러 학습에 의한 개체의 국부적 향상이 전체적인 성능 향상에 기여함을 알 수 있었고 제안한 학습 전략이 기존의 방법보다 더 빨리 전역 최적 해를 찾을 수 있음을 증명하였다.

• 유통과학연구
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• 제14권2호
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• pp.73-82
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• 2016

Purpose - Counterproductive work behavior(CWB) was typically categorized according to the behavior whether it targets other people(i.e., interpersonal CWB: I-CWB). Employing organizations(i.e., organizational CWB: O-CWB) has emerged as major concerns among researchers, managers, and the general public. An abundance of researches has informed us about the understanding for the antecedents of CWB, whereas little is known about the antecedents of CWB directed distribution service in employee's emotional labor. Therefore, the purpose of this research is to propose a research model in which surface acting enhances emotional exhaustion as an emotional labor strategy, which eventually increases counterproductive work behavior(including I-CWM and O-CWB). Research design, data, and methodology - This empirical research data were gathered from the samples of full time frontline hotel employees(including front office, call center, food/beverage, concierge, and room service) in South Korea. Six hotels were selected ranged from four to five stars, including privately owned and joint-venture properties. A convenience sampling method was used to select hotels. Full time frontline hotel employees from the six hotels were surveyed using a self-administered instrument for data collection. With the strong support of hotel managers, a total of 300 questionnaires were distributed, and 252 responses were collected indicating a response rate of 84.0%. In the process of working with the 252 samples, structural equation modeling is employed to test research hypotheses(H1: The relationship between surface acting and Interpersonal counterproductive work behavior(I-CWB) is mediated by emotional exhaustion, H2: The relationship between surface acting and organizational counterproductive work behavior(O-CWB) is mediated by emotional exhaustion). SPSS 18.0 and M-Plus 7.31 software were used for the data analysis. Descriptive statistics were used to assess the distribution of the employee profiles and correlations between factors. M-Plus 7.31 software was used to test the model fit, validity, and reliability of the factors, significance of the relationship between factors, and the effects of factors in the model. Results - To test our mediation hypotheses, we used an analytical strategy suggested by Preacher & Hayes (2008) and Shrout & Bolger (2002). This mediation approach directly tests the indirect effect between the predictor and the criterion variables through the mediator via a bootstrapping procedure. Thus, it addresses some weaknesses associated with the Sobel test. We found that surface acting was positively related to emotional exhaustion. Furthermore, emotional exhaustion was a significant predictor from the two kinds of counterproductive work behavior. In addition, surface acting was not significantly associated with the two kinds of counterproductive work behavior. These results indicated that the surface acting by frontline hotel employees was associated with higher emotional exhaustion, which is related with higher interpersonal counterproductive work behavior(I-CWB) and organizational counterproductive work behavior(O-CWB). In sum, we confirmed that the positive relationship between surface acting and the two kinds of counterproductive work behavior was fully mediated by emotional exhaustion. Conclusions - The current research broadens the conceptual work and empirical studies in counterproductive work behavior literature by representing a fundamental mechanism that how surface acting affects counterproductive work behavior.

• 유통과학연구
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• 제16권5호
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• pp.71-81
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• 2018

Purpose - Our research aims to investigate the mediating effect of employee creativity on the relationship between intrinsic motivation and job performance using relationship using Chinese department salespeople samples. Another objective of this study is to be clear boundary conditions that strengthen or weaken the effects of intrinsic motivation on work outcomes (i.e., employee creativity and job performance). Drawing on JD-R theory, we suggest that the two types of coworker support play differential moderating roles in the intrinsic motivation, employee creativity relationship by increasing or decreasing job resources and demands in different ways. Research design, data, and methodology - This empirical study data were collected from gathered from a sample of full time salespeople in China. A total of 550 questionnaires were distributed and 300 responses were collected, indicating a response rate of 84.0%. Working with a sample of 300 salespeople working in a department store in China. SPSS 18.0, Process 2.16 Macro, and M-Plus 8.0 software were used in the data analysis. Descriptive statistics were used to evaluate the distribution of the employee profiles and correlations between variables. M-Plus 8.0 software was used to test the model fit, validity and reliability of the variables. Finally, all research hypotheses was estimated by SPSS Macro 2.16. Results - To test our research hypotheses, we employed an analytical strategy suggested by Hayes (2013; 2015) and Shrout and Bolger (2002). In this study, we tested the relationship between intrinsic motivation and job performance throughout employee creativity. Results showed intrinsic motivation and job performance was partially mediated by employee creativity. The positive relationship between intrinsic motivation and employee creativity when coworker emotional support was high than when it was low. In contrast, the positive association between intrinsic motivation and employee creativity was stronger when coworker instrumental support was low than when it was high. Coworker emotional and instrumental support further moderated the indirect effect of intrinsic motivation on job performance through employee creativity. Conclusions - This study extends the conceptual model and empirical researches in coworker supports literature by representing a fundamental mechanism of how salespeople's intrinsic motivation and job performance throughout employee creativity.

• 마케팅과학연구
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• 제19권3호
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• pp.28-36
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• 2009

现有的文献广泛的关注财阀以及他们的所有权和支配权的优点和弱点, 但是几乎没有关于韩国非财阀公司的研究. 然而, Lee, Lee and Pennings (2001)并没有特别的探讨在韩国国内市场非财阀公司为求生存而对抗财阀公司的具有竞争力的战略. 本文的研究动机是通过四个探索性案例的研究, 韩国非财阀公司对抗财阀公司的成功的竞争战略和提出的建议可能会对其他的企业以及公共政策制定者有所帮助. 从产品相似性和公司内的合作关系分别定义竞争和合作的概念. 从这两个方面, 我们开发了以下$2{\times}2$ 矩阵, 为非财阀公司对抗财阀公司提供四种竞争战略. 在小组1的非财阀公司在高端市场对财阀公司让步, 但在低端市场有 "我也是在低端市场" 的产品, 同时承认在高端市场的财阀. 在小组2, 非财阀公司以供应商或互补企业的身份成为财阀公司的合伙人. 在小组3, 非财阀企业从事与财阀直接竞争. 在小组4, 非财阀企业的目标, 以产品创新或服务填补目标市场空白点. 我们选择的4个公司分别是E‐Rae电子企业公司(共存方), Intops(供应商), Pantech(竞争对手)和Humax(小众市场成员). 通过分析这4个案例, 相互提供更丰富的洞察力战略. 基于我们的概念框架, 提出下列假设 : 假设1 : 与财阀公司有合作关系的非财阀公司比没有合作关系的公司表现得更好. 假设1a: 共存方会比竞争方表现得更好. 假设1b: 合伙方会比小众市场成员表现得更好. 假设2: 与财阀公司的产品没有相似性的公司比有相似性的公司表现得要更好. 假设2a: 合伙方比共存放表现得更好 假设2b: 小众市场成员会比竞争方表现得更好. 假设3: 小众市场成员应比共存方表现得更好. 假设4: 按绩效的降序排列依次是合作者, 小众市场成员, 共存方, 竞争方. 一组专家按照我们4组的分类把216家非财阀公司分类. 用SPSS统计软件中的简单方差分析来检验假设. 结果发现. 与财阀公司有合作关系的以及提供与财阀公司不同的产品或服务比较好. 很明确的一点是, 平均来说, 若要对抗财阀公司中获利, 其战略是成为合伙人(供应商或组成部分). 直接与财阀公司硬碰硬的竞争是要付出极高代价的战略, 而这种代价不是非财阀公司能负担得起的. 避免与财阀公司迎面竞争的战略是用不同的产品服务于利己市场, 或是服务于被财阀公司忽视掉的低端市场. 些战略是比较好的生存战略. 本文说明在财阀环境中, 韩国的中小型非财阀公司有一些方法可以生存, 尽管不是没有风险. 根据不同的竞争组合, 合作的公司可以根据产品相似性以及合作关系的维度来选择定位从而制定自己的竞争战略. 例如共存方, 竞争对手, 合伙人, 小众市场成员. 根据我们的探索性案例分析, 合伙人对非财阀公司来说可能是最好的战略, 而竞争者则是有很大风险的. 小众市场成员和共存方处于中间, 但前者比后者要好. 很多中小型企业的管理者只是用简单的, 不是合作就是竞争的观点来审视市场的领导者‐典型的就是财阀. 结果. 很多非财阀公司变成被动的合作者或被自己的竞争对手财阀所击败. 事实上, 合作和竞争并不是互相排斥的, 是可以同时被追求的. 正如本文所建议的, 非财阀公司可以根据他们的环境, 内部资源和能力灵活的选择合作和竞争.