• 분석과학
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• 제5권2호
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• pp.217-222
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• 1992

수은침투법을 이용하여 AIN의 이장성형체와 건조가압성형체의 기공구조 해석을 시도하였다. 좁은 기공크기 분포와 높은 충진밀도를 가진 이장성형체에서 소결도가 높고 2차상의 분포가 균일하였다. 수은침투법에 의한 기공크기 분포 해석은 잉크병 현상이 없을 때만 유효하지만 정량미시 분석과의 비교결과 기공률의 측정은 개기공 상태이면 유효함을 보였다.

• International Journal of Reliability and Applications
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• 제13권1호
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• pp.49-56
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• 2012

Using total time on test transform (TTT), a new approach is taken for testing exponentiality versus the unknown age, exponential better than equilibrium life in convex ordering (EBELC). Selected critical values are tabulated for sample size n =2(2)50 and powers of the test are estimated for some commonly used distributions in reliability. Finally real example is presented to illustrate the theoretical results.

• 대한치과교정학회지
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• 제49권6호
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• pp.381-392
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• 2019

Objective: The objective of this two-arm parallel trial was to compare the type of tooth movement during en masse retraction of the maxillary anterior teeth using labial versus lingual biocreative therapy. Methods: Twenty-eight subjects were randomized in a 1 : 1 ratio to either the labial or lingual group. En masse anterior retraction was performed using labial biocreative therapy in group A and lingual biocreative therapy in group B. Cone beam computed tomography scans were taken before and after retraction and the primary outcome was the type of tooth movement during anterior retraction. Data were analyzed using paired t-tests for comparisons within each group and independent-sample t-test for comparison of the mean treatment changes between the two groups. Results: Significant differences were found between the two groups in relation to the type of tooth movement (labiolingual inclination of the central incisor; mean difference, $5.85{\pm}1.85^{\circ}$). The canine showed significant distal tipping in the lingual group (mean difference, $6.98{\pm}1.25^{\circ}$). The canine was significantly more intruded in the lingual group (mean difference, $1.67{\pm}0.49mm$). Good anchorage control and significant soft tissue changes occurred in both groups. No serious adverse effects were detected. Conclusions: With a 10-mm retraction hook, the labial biocreative technique with the reverse curve overlay provided anterior retraction with good torque control, while in the lingual group, anterior retraction occurred with controlled tipping movement with significant distal tipping and intrusion of the canine (trial registration: The trial was registered at ClinicalTrials.gov [NCT03239275]).

• 한국세라믹학회지
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• 제27권8호
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• pp.956-956
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• 1990

석탄회의 탄소가 첨가된 질화반응시에 생성된 AIN, SiC 그리고 Si3N4 등의 생성물 분포를 반응온도, 시간 그리고 탄소의 첨가량에 따라 검토하였다. AIN의 조성은 시료입자가 작을수록 증가하였으며 반응온도 14500~1500℃와 약 2시간의 반응시간 그리고 약 30%의 탄소 첨가량 (시료무게 기준) 에서 최대값을 나타내었다. SiC와 Si3N4 조성변화는 서로 상반된 경향을 보였으며 반응온도가 낮고 반응시간이 작으며 그리고 탄소첨가량이 증가할 수록 SiC의 조성은 Si3N4 에 비하여 크게 나타났다.

• 유통과학연구
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• 제20권10호
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• pp.19-29
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• 2022

Purpose: This study was conducted to gauge the economic evaluation and sample distribution of conserving the Belum Royal State Park (BRSP) in Perak, Malaysia and to identify factors influencing its use by the community. This study aims to examine community perception on the conservation of the Belum Royal State Park (BRSP) and maximum community's willingness to pay for park entry permits fees. Research design, data and methodology: A questionnaire survey was conducted involving a total of 280 respondents. The study adopted the Dichotomous Choice Contingent Valuation Approach (DC-CVM) and the Logistic Model, to estimate the maximum community's willingness to pay for park entry permits fees. Results: The results established that the factors of respondent's occupation, income, ecotourism influence on the BRSP and maximum entry price, significantly influenced visitors' decision on community's willingness to pay. The average community's willingness to pay was RM9.68 per person. Conclusions: In conclusion, surveillance and patrols in protected areas should be expanded. The extra expense for ensuring safety can be offset through income from ecotourism that should also benefit the local community on economic evaluation and equal distribution on the BRSP.

• 한국진공학회지
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• 제14권4호
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• pp.201-206
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• 2005

본 연구에서는 HVPE (Hydride Vapor Phase Epitaxy) 방법으로 Si 위에 GaN/AIN/Al/Si 구조를 제작하고, AlN 버퍼층의 두께에 따른 광학적 특성을 조사함으로써 효과적인 eaN 성장을 위한HVPE에서의 공정 방법을 개선하고자 하였다. 이를 위해 Al을 증착한 Si 기판과 그렇지 않은 경우를 PL측정을 통해 그 효과를 관찰하였고, $5{\AA}$ 두께의 Al 대해 AlN 버퍼층의 두께를 변화시켜가면서 GaN를 성장시켜 그 특성을 조사하였다. Al을 증착한 경우가 증착하지 않은 경우에 비해 광학적 특성이 우수한 것으로 나타났으며, AlN의 두께 변화에 대해서는 양질의 GaN를 얻기 위한 최적의 두께는 약 $260{\AA}$ 인 것으로 나타났다. 이 경우 SEM을 이용한 표면사진에서 GaN의 초기성장이 hexagonal형태로 성장되고 있음을 관찰할 수 있었다. 또한 XRD의 회절 패턴은 GaN가 {0001} 방향으로 우선 배향성을 가지고 성장되고 있음을 보여주고 있었다.

• Nuclear Engineering and Technology
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• 제51권3호
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• pp.784-791
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• 2019

In the present study, a series of tungsten austenitic stainless steel alloys have been developed by interchanging the molybdenum in standard SS316 by tungsten. This was done to minimize the long-life residual activation occurred in molybdenum and nickel after decommissioning of the power plant. The microstructure and mechanical properties of the prepared alloys are determined. For the sake of increasing multifunction property of such series of tungsten-based austenitic stainless steel alloys, gamma shielding properties were studied experimentally by means of NaI(Tl) detector and theoretically calculated by using the XCOM program. Moreover, fast neutrons macroscopic removal cross-section been calculated. The obtained combined mechanical, structural and shielding properties indicated that the modified austenitic stainless steel sample containing 1.79% tungsten and 0.64% molybdenum has preferable properties among all other investigated samples in comparison with the standard SS316. These properties nominate this new composition in several nuclear application domains such as, nuclear shielding domain.

• The Journal of Asian Finance, Economics and Business
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• 제6권3호
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• pp.225-234
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• 2019

The study aims to explore key dimensions of service quality of E-Retailing of Islamic banks in the Kingdom of Saudi Arabia. The convenience sample size consists of 373 respondents who regularly use online Islamic banking facilities in Saudi Arabia was used. For measuring the consumers' perspective, a four-factor E-SERVQUAL scale; namely efficiency, system availability, fulfillment, and privacy was used. Exploratory Factor Analysis and Confirmatory Factor Analysis are used to test the model fitness. Structural equation modelling is utilized to determine the impact of E-service quality dimensions on customers' satisfaction. The results of the study reveal that 1) reliability as a dimension of E-retailing of Islamic banks made a significant impact on customers' overall satisfaction; 2) there is a positive significant relationship between responsiveness and customers' overall satisfaction. One unit increased in responsive leads to 0.763 unit increases in the overall satisfaction of the customer; and 3) ease of use is the most important dimensions of service quality of E-retailing of Islamic banks. One unit increases in Security/ Privacy leads to 0.473 unit increases in overall satisfaction. There is a positive impact of good E-service on customers' satisfaction, but it does not override unsatisfactory performance in other areas.

• Journal of Magnetics
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• 제12권4호
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• pp.149-151
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• 2007

The AlCrN films were grown by RF reactive sputtering method under the selected conditions. The Cr concentration was varied by the number of Cr pieces placed on the Al target. The sample quality has been studied by XRD, Auger spectroscopy, optical absorption and electrical resistant measurements. The XRD and Auger results show that the samples consist of a major phase with the $Al_{1-x}Cr_xN$ formula, which has a hexagonal structure, and a few percents at. of oxygen, which may form $Al_2O_3$. There exist the Cr clusters in the samples with high concentration of Cr. The optical absorption measurement provides the information about the band gap that relates strongly to the quality of samples. The quality of samples is also clearly reflected in electrical measurement, i.e., the temperature dependence of resistance exhibits a semiconductor characteristic only for the samples that have no Cr cluster. In these cases, the values of ionization energies $E_a$ can be derived from R(T) plots by using the function R(T) = Ro exp $(E_a/k_BT)$.

• The Journal of Asian Finance, Economics and Business
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• 제9권6호
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• pp.331-341
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• 2022

Through emotional exhaustion, this study empirically tests followers' behavioral responses to autocratic leaders. The current research focuses on effects caused by despotic leadership on followers' emotional exhaustion, which leads to employee outcomes such as interpersonal deviances and indirect aggression. The association between despotic leadership and results (employee interpersonal deviance and indirect violence) is investigated in this study. In this study, emotional exhaustion is used as a mediator. Furthermore, negative affectivity is used as a moderator between despotic leadership and emotional exhaustion. A time-lagged framework is employed with a sample of 255 respondents. Age, qualification, marital status, gender, grade, type of organization, department, and job experience are among the eight demographical questions in this study. After evaluating the data for normality, correlation analysis was performed, followed by moderation and mediation analysis. The current study explores the link between despotic leadership and emotional exhaustion among followers, arguing that a despotic leader will leave followers exhausted at work. Emotional exhaustion was also linked to interpersonal deviances, such as indirect aggression, in a significant and positive way. Employee outcomes, such as interpersonal deviances and indirect aggressiveness through emotional exhaustion, will be influenced by a despotic leader, according to the findings.