• The korean journal of orthodontics
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• v.49 no.4
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• pp.246-253
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• 2019

Objective: To evaluate the effectiveness of three different caries-preventing agents on artificial caries in a Streptococcus mutans-based caries model. Methods: Sixty-five caries-free human molar enamel blocks were treated with a demineralization solution and a remineralization solution. The specimens were assigned to the following groups according to the caries-protective product applied: group A, chlorhexidine varnish; group B, fluoride-releasing chemically cured sealant; group C, fluoride-releasing lightcured sealant; group D, positive control (specimens that were subjected to de- and remineralization cycles without treatment with any caries-protective agents); and group E, negative control (specimens that were not subjected to de- and remineralization cycles). Samples in groups A-D were stored in demineralization solution with S. mutans and thereafter in artificial saliva. This procedure was performed for 30 days. Average fluorescence loss (${\Delta}F$) and surface size of the lesions were measured using quantitative light-induced fluorescence at baseline and on the 7th, 14th, and 30th days. Results: After 30 days, group A demonstrated a significant increase in ΔF and the surface size of the lesions, no significant difference in comparison with the positive control group, and a significant difference in comparison with the negative control group. Group B showed no significant changes in both parameters at any of the measurement points. While group C showed increased ${\Delta}F$ after 14 days, no significant fluorescence change was observed after 30 days. Conclusions: Both fluoride-releasing sealants (chemically or light-cured) show anti-cariogenic effects, but the use of chlorhexidine varnish for the purpose of caries protection needs to be reconsidered.

• Healthcare Informatics Research
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• v.24 no.4
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• pp.292-299
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• 2018

Objectives: The aim of the present study was to assess the frequency of use, and preferences regarding information and communication technologies (ICTs) among Ecuadorian patients with chronic kidney disease (CKD) undergoing hemodialysis. Methods: We conducted an anonymous cross-sectional survey-based study from January 2016 to April 2017, involving 393 patients with end-stage renal disease from 9 hemodialysis centers, in which they rated their use and preferences of various ICTs through a modified version of the Michigan Questionnaire. The questionnaire collected information regarding demographics, patients' interest in obtaining health-related information through ICTs, and interest in using ICTs as a potential way to communicate with their healthcare providers. A chi-square test for association and adjusted regression analyses were performed. Results: Among all patients who participated, 64.3% reported owning a cellphone, with less than a third reporting active Internet connection. The most used ICT for obtaining information about CKD and/or hemodialysis was web-based Internet, followed by YouTube. SMS was rated the highest to receive and seek health-related information, followed by Facebook. Younger age and higher levels of education were associated with a higher overall usage of ICTs. Finally, more than half of the patients reported interest in using WhatsApp for communicating with their healthcare providers. Conclusions: Understanding the preferences of ICTs among patients with CKD undergoing hemodialysis could help to improve their outcomes through the potential uses and benefits of ICTs. Further research is needed to assess their role in improving the care of patients with chronic diseases.

• Animal Bioscience
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• v.34 no.4
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• pp.558-566
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• 2021

Objective: Objectives were to estimate energy and protein requirements of dairy crossbred steers, as well as to evaluate equations previously described in the literature (HH46 and CS16) to predict the carcass and empty body chemical composition of crossbred dairy cattle. Methods: Thirty-three Holstein×Zebu steers, aged 19±1 months old, with an initial shrunk body weight (BW) of 324±7.7 kg, were randomly divided into three groups: reference group (n = 5), maintenance level (1.17% BW; n = 4), and the remaining 24 steers were randomly allocated to 1 of 4 treatments. Treatments were: intake restricted to 85% of ad libitum feed intake for either 0, 28, 42, or 84 d of an 84-d finishing period. Results: The net energy and the metabolizable protein requirements for maintenance were 0.083 Mcal/EBW0.75/d and 4.40 g/EBW0.75, respectively. The net energy (NEG) and protein (NPG) requirements for growth can be estimated with the following equations: NEG (Mcal/kg EBG) = $0.2973_{({\pm}0.1212)}{\times}EBW^{0.4336_{({\pm}0.1002)}$ and NPG (g/d) = 183.6(±22.5333)×EBG-2.0693(±4.7254)×RE, where EBW, empty BW; EBG, empty body gain; and RE, retained energy. Crude protein (CP) and ether extract (EE) chemical contents in carcass, and all the chemical components in the empty body were precisely and accurately estimated by CS16 equations. However, water content in carcass was better predicted by HH46 equation. Conclusion: The equations proposed in this study can be used for estimating the energy and protein requirements of crossbred dairy steers. The CS16 equations were the best estimator for CP and EE chemical contents in carcass, and all chemical components in the empty body of crossbred dairy steers, whereas water in carcass was better estimated using the HH46 equations.

• International Journal of Knowledge Content Development & Technology
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• v.11 no.1
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• pp.49-64
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• 2021

This research paper delved into the availability and utilization of library portal services for research in university libraries in Nigeria. Two research questions and two null hypotheses were formulated to guide the study. A structured questionnaire was used for data collection. The study was carried out in Nnamdi Azikiwe Library, University of Nigeria Nsukka (UNN) and Felix Aghagbo Nwako Library, Nnamdi Azikiwe University Library (UNIZIK), Awka. A total of 70 professionals (librarians and system analysts) in these libraries supplied data for the study. Data collected was analyzed using mean and standard deviation. These were used to answer the research questions while the null hypotheses were tested using t-test statistic at 0.05 level of significance and 68 degree of freedom. Major findings showed that portal services available in the library showed that the areas of availability of library portal services in Nnamdi Azikiwe Library, U.N.N. includes Agriculture, Health Sciences, Engineering, Environmental Sciences and information about institution, Social Sciences, Arts and Humanities, Natural Sciences. In Festus Aghagbo Nwako Library, Awka, the areas of Portal Library Services include Career Development, Federal Government Programs, Environmental Sciences, Biological Sciences, Social Sciences, Arts and Humanities, Engineering, and Health Sciences. Findings on extent of utilization of portal services available in the libraries indicated that portal services are utilized to a low extent in the university libraries. Furthermore, librarians did not significantly differ in their opinions on the availability of library portal services and on the extent of utilization of library portal services in the libraries under study. It is therefore recommended that provisions should be made by the universities and library management to provide and update required portal services in addition to creating enabling environment for enhanced access and utilization of these services. The governments must make an effort to provide funds for policy implementation, necessary technology training for librarians and users, and develop general information infrastructure.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.331-336
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• 2021

This study first examined the social meanings of typicality found in the prison, (solitary) confinement, and conduit(passage) in Peter Halley's works, in which both the prison and (solitary) confinement represent a suppressed structural framework. The former has freedom and escape excluded from it, and the latter allows for mutual regulation and connection as a space of positive mediation. Conduits are interpreted to be flexible and have the potential of creating something new through connection and communication with the outside world. The study then compared and analyzed the meanings of typicality in Halley's works and the concept of segments proposed by Gilles Deleuze and Félix Guattari as social justice in that both of them were in the same context. The findings lead to a conclusion that Halley's prison, (solitary) confinement, and conduit(passage) can be connected to a solid, flexible, and escape segment, respectively, by Deleuze and Guattari.

• Journal of the Korean Society of Systems Engineering
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• v.18 no.2
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• pp.75-93
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• 2022

Machine learning (ML) data-driven meta-model is proposed as a surrogate model to reduce the excessive computational cost of the physics-based model and facilitate the real-time prediction of a nuclear power plant's transient response. To forecast the transient response three machine learning (ML) meta-models based on recurrent neural networks (RNNs); specifically, Long Short Term Memory (LSTM), Gated Recurrent Unit (GRU), and a sequence combination of Convolutional Neural Network (CNN) and LSTM are developed. The chosen accident scenario is a control element assembly withdrawal at power concurrent with the Loss Of Offsite Power (LOOP). The transient response was obtained using the best estimate thermal hydraulics code, MARS-KS, and cross-validated against the Design and control document (DCD). DAKOTA software is loosely coupled with MARS-KS code via a python interface to perform the Best Estimate Plus Uncertainty Quantification (BEPU) analysis and generate a time series database of the system response to train, test and validate the ML meta-models. Key uncertain parameters identified as required by the CASU methodology were propagated using the non-parametric Monte-Carlo (MC) random propagation and Latin Hypercube Sampling technique until a statistically significant database (181 samples) as required by Wilk's fifth order is achieved with 95% probability and 95% confidence level. The three ML RNN models were built and optimized with the help of the Talos tool and demonstrated excellent performance in forecasting the most probable NPP transient response. This research was guided by the Systems Engineering (SE) approach for the systematic and efficient planning and execution of the research.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.456-456
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• 2021

하상 변화는 유량이나 유사의 흐름에 따라 침식, 운반, 퇴적되어 변화하며, 하상변동에 의한 결과는 하천의 형태 (직렬,복렬, 곡렬 등)나 서식처의 구조 (여울과 소, 웅덩이, 습지 등) 형성 로 나타난다. 이어서 서식처 구조의 다양성은 생물다양성에 긍정적인 영향을 미친다. 본 연구에서는 수리 (유량이나 유사량)-지형(서식처 구조)-생태 (생물다양성)을 연계하여 관리하기 위한 생태적인 하천관리 프레임을 제시하기 위하여, 지형과 생물상의 관계를 우선 파악하고자 한다. 국내 하천은 수생태 건강성 평가 중 서식 및 수변환경 지수(HRI, Habitat and Riparian Index)를 활용하여 하천의 형상 및 자연성을 평가한다. 해당 지수는 하천의 자연성을 판단할 수 있으나 유량이나 유사량 등과 같이 수리적 조건과 연계하여 하천환경 변화를 예측하기 어렵기 때문에, 본 연구에서는 하천의 자연성을 판단하는 지형변수들을 제안하고, 생물상과 상관관계를 분석한다. 수질 변화가 급격하지 않는(년간 변화폭이 일정한) 금강 유역의 지천 (갑천, 미호천, 논산천, 유구천 등) 중 생태계 건강성 평가 지수가 산정되어 있는 지점을 기준으로 상·하류 약 5 km 구간들을 대상으로 한다. 지형 변수로는 (항공사진을 이용한)사주 비율(사주면적/제방 내 홍수터 면적), 사주 식생비율(식생면적/사주면적)과 사주 변동량(연간 사주 이동량), 서식처 구조의 다양성(여울, 소, 웅덩이 등), 기존의 서식 및 수변환경 지수 등을 활용하고, 생물 변수로는 저서동물지수(BMI, Benthic Macroinvertebrate Index), 저서동물의 우점도, 어류생물지수(FAI, Fish Assessment Index), 어류생물지수에 활용하는 국내종의 총 종수, 여울성 저서종수, 민감종수 등을 활용한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.166-166
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• 2022

본 연구의 목적은 고전적 순간단위도 모형 중의 하나인 Nash 모형의 매개변수와 하천망의 동적 Fractal 차원 사이의 관계를 체계적으로 분석하여 해당 매개변수의 수문학적 의미를 추론해 보는 것이다. Nash 모형의 경우, GIUH 이론과의 결합을 통하여 Horton 비를 기반으로 한 두 매개변수의 지형학적 추정 방법이 일찍부터 제안되어 왔다 (Rosso, 1984; Bhunya, 2008). 특히 Liu(1992)는 2차원 자유 Euclidean 공간 내에서 percolation cluster 모형의 응집구조와 유역의 배수구조 사이의 비교를 통하여 하천망의 Fractal 차원을 정적 Fractal 차원과 동적 Fractal 차원으로 구분하고 양자의 수문학적 의미에 대하여 강조한 바 있다. 본 연구에서는 문헌 조사 (Morisawa, 1962; Marani et al., 1991; Rosso et al., 1991)를 통하여 수집한 비교적 신뢰성 있는 국외 하천망들에 관한 정보를 기반으로 Nash 모형의 매개변수와 하천망의 동적 Fractal 차원 사이의 관계를 분석해 보았다. 주요한 결과로서 Nash 모형의 형상 매개변수와 하천망의 Fractal 차원 사이에는 밀접한 상관관계가 존재함을 알 수 있었으며 이를 통하여 하천망의 Fractal 차원을 이용하여 해당 매개변수를 직접 추정할 수 있는 관계식을 제시할 수 있을 것으로 판단된다. 또한 분광 차원과 Nash 모형의 첨두 좌표 사이의 관계를 통하여 겉보기에서로 다른 유역들 사이에 존재할 수 있는 수문학적 상사성을 평가할 수 있는 기준의 수립 역시 본 연구과정을 통하여 제시할 수 있으로 판단된다. 후속 연구로서 국내외 다수 유역들에 대한 지형분석을 통하여 본 연구에서 얻은 결과의 보편성을 검정하고 수문학적 자료들에 대한 검증을 통하여 Nash 모형을 기반으로 한 다양한 수문학적 모형들의 개선 방안을 제시해 보고자 한다.

• Asia Marketing Journal
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• v.16 no.2
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• pp.59-75
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• 2014

Although previous works have established that mood can considerably influence consumer behavior (Vohs et al. 2007), they provided inconsistent results (Cohen et al. 2008). In particular, previous works only examined the willingness of consumers to regulate their mood and implicitly assumed that consumers have the control to regulate their mood states. Thus, this research intends to fill the current gap in the extant literatures by investigating whether consumer locus of control (CLOC) can act as a moderator for mood effects on consumers' likelihood to purchase. In an experiment, participants' CLOC was initially measured. Afterwards, they watched different video clips to induce different mood states. Finally, participants rated their likelihood to purchase after seeing an advertisement. The results suggest that, in the positive mood, CLOC tendencies do not impact consumers' likelihood to purchase. However, in the negative mood, internal CLOC consumers show a higher likelihood to purchase than external CLOC consumers. This phenomenon occurs because consumers with high internal CLOC tendencies have the motivation to regulate their negative mood. These findings extend the extant literatures in four aspects. First, this paper shows that the CLOC tendencies could influence consumers' motivation to regulate their negative mood. Second, this research examines the moderating effect of CLOC in the relationship between mood and consumers' likelihood to purchase. Third, the results add further evidence regarding the role of negative mood in the self-regulation process. Finally, this research also shows that mood can unconsciously influence consumer behavior. This paper provides two managerial implications. First, marketers should consider the mood states and consumers' control tendencies in creating advertisements. Second, firms in retail or service business should aim to evoke a positive mood on consumers so that their CLOC tendencies would not influence their behaviors.

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.55.1-55.12
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• 2020

Objectives: This study investigated the effects of physically damaged and resin-contaminated tips on radiant emittance, comparing them with new undamaged, non-contaminated tips using 3 pieces of spectrophotometric laboratory equipment. Materials and Methods: Nine tips with damage and/or resin contaminants from actual clinical situations were compared with a new tip without damage or contamination (control group). The radiant emittance was recorded using 3 spectrophotometric methods: a laboratory-grade thermopile, a laboratory-grade integrating sphere, and a portable light collector (checkMARC). Results: A significant difference between the laboratory-grade thermopile and the laboratory-grade integrating sphere was found when the radiant emittance values of the control or damaged/contaminated tips were investigated (p < 0.05), but both methods were comparable to checkMARC (p > 0.05). Regardless of the method used to quantify the light output, the mean radiant emittance values of the damaged/contaminated tips were significantly lower than those of the control (p < 0.05). The beam profile of the damaged/contaminated tips was less homogeneous than that of the control. Conclusions: Damaged/contaminated tips can reduce the radiant emittance output and the homogeneity of the beam, which may affect the energy delivered to composite restorations. The checkMARC spectrophotometer device can be used in dental offices, as it provided values close to those produced by a laboratory-grade integrated sphere spectrophotometer. Dentists should assess the radiant emittance of their light-curing units to ensure optimal curing in photoactivated, resin-based materials.