• Imaging Science in Dentistry
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• v.35 no.1
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• pp.33-40
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• 2005

Purpose : (1) To analyse the effect of exposure time, ROI size and one impact factor in the image processing procedure on estimates of fractal dimension; and (2) to analyse the correlated relationship between the fractal dimension and the Cu-Eq value (bone density). Materials and Methods : The cylindric bone phantoms of 6 large and 5 small diameter having different bone densities respectively and human dry mandible segment with copper step wedge were radiographed at 1.0 and 1.2 sec esposure (70 kVp, 7 mA) using one occlusal film and digitized. Eleven rectangular ROIs from 11 cylindric bone phantoms and 4 rectan-gular ROIs from cortical, middle, periodontal regions, and socket of bone were selected. Gaussian blurred Image was subtracted from original image of each ROI and multiplied respectively by 1, 0.8, and 0.5, and then the image was made binary, eroded and dilated once, and skeletonized. The fractal dimension was calculated by means of a box counting method in the software ImageJ. Results : The fractal dimension was decreased gradually with continued bone density decrease showing strong correlations (bone phantom; r> 0.87, bone; r> 0.68) under 70 kVp 1.0 sec M = 0.8. Fractal dimensions showed the significant differerence (p < 0.05) between two different exposure times on the same small ROI of bone phantom. Fractal dimensions between two different sizes of ROI on bone phantom showed the significant differerence (p < 0.05) under 1.2 sec exposure, but did not show it (p > 0.05) under 1.0 sec exposure. Conclusions : Exposure time, ROI size, and modifying factor during subtracting could become impacting on the results of fractal dimension. Fractal analysis with thoroughly evaluated method considering the various impacting factors on the results could be useful in assessing the bone density in dental radiography.

• Structural Engineering and Mechanics
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• v.71 no.4
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• pp.391-405
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• 2019

Compared to the ambient vibration test mainly identifying the structural modal parameters, such as frequency, damping and mode shapes, the impact testing, which benefits from measuring both impacting forces and structural responses, has the merit to identify not only the structural modal parameters but also more detailed structural parameters, in particular flexibility. However, in traditional impact tests, an impacting hammer or artificial excitation device is employed, which restricts the efficiency of tests on various bridge structures. To resolve this problem, we propose a new method whereby a moving vehicle is taken as a continuous exciter and develop a corresponding flexibility identification theory, in which the continuous wheel forces induced by the moving vehicle is considered as structural input and the acceleration response of the bridge as the output, thus a structural flexibility matrix can be identified and then structural deflections of the bridge under arbitrary static loads can be predicted. The proposed method is more convenient, time-saving and cost-effective compared with traditional impact tests. However, because the proposed test produces a spatially continuous force while classical impact forces are spatially discrete, a new flexibility identification theory is required, and a novel structural identification method involving with equivalent load distribution, the enhanced Frequency Response Function (eFRFs) construction and modal scaling factor identification is proposed to make use of the continuous excitation force to identify the basic modal parameters as well as the structural flexibility. Laboratory and numerical examples are given, which validate the effectiveness of the proposed method. Furthermore, parametric analysis including road roughness, vehicle speed, vehicle weight, vehicle's stiffness and damping are conducted and the results obtained demonstrate that the developed method has strong robustness except that the relative error increases with the increase of measurement noise.

• Journal of Information Processing Systems
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• v.16 no.4
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• pp.784-794
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• 2020

In order to effectively evaluate the urban water security, the study investigates a novel system to assess factors that impact urban water security and builds an urban water poverty evaluation index system. Based on the contribution rates of Resource, Access, Capacity, Use, and Environment, the study adopts the Water Poverty Index (WPI) model to evaluate the water poverty levels of 14 cities in Gansu during 2011-2018 and uses the least variance method to evaluate water poverty space drive types. The case study results show that the water poverty space drive types of 14 cites fall into four categories. The first category is the dual factor dominant type driven by environment and resources, which includes Lanzhou, Qingyang, Jiuquan, and Jiayuguan. The second category is the three-factor dominant type driven by Access, Use, and Capability, which includes Longnan, Linxia, and Gannan. The third category is the four-factor dominant type driven by Resource, Access, Capability, and Environment, which includes Jinchang, Pingliang, Wuwei, Baiyin, and Zhangye. The fourth category is the five-factor dominant type, which includes Tianshui and Dingxi. The driven types impacting the urban water security factors reflected by the WPI and its model are clear and accurate. The divisions of the urban water security level supply a reliable theoretical and numerical basis for an urban water security early warning mechanism.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.291-300
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• 2020

This paper studies the factors affecting university and industry collaboration in education in the hospitality industry in Ho Chi Minh City (Vietnam) from a company perspective. The authors use qualitative method and quantitative research to study the matters, specifically using scales and data collected for Cronbach alpha reliability testing, analysizing the discovery factor of EFA, CFA and verifying the regression models through AMOS software with SEM linear modeling. The study proposes four factors: (1) organization factors, (2) contextual factors, (3) process factors, and (4) cooperation perspective impacting on the benefits factors and university and industry collaboration in education. In addition, it is also found that benefits factors has a direct and positive impact on the collaboration in education. The results suggest that the process factor had the strongest positive, followed by the contextual factor. The findings revealed that the benefit factors were significantly related to collaboration in education, which affects university and industry hospitality alliances. This finding confirm that the cooperation perspective (QD) and contextual factors (HC) are critical in collaboration between university and industry. A new point of interest is also identified that the benefits of training links are quite dependent on the linking perspective from tourism businesses.

• Journal of Korean society of Dental Hygiene
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• v.19 no.6
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• pp.1037-1046
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• 2019

Objectives: This study was conducted to test the critical thinking tendency, clinical practice satisfaction, and clinical performance, and analyze the factors impacting clinical practice satisfaction and clinical performance of dental hygiene students. Methods: The study conducted a written survey during the period between 30 July ~20 August 2019, among 3rd and 4th year dental hygiene students from Seoul, Gyung-gi region, who had taken clinical practice courses. Using SPSS 22.0 program (IBM SPSS statistics, New York, USA), the study analyzed the final 174 cases. Results: Dental hygiene students scored 3.33±0.43, 3.48±0.83, and 3.30±0.58 for critical thinking, clinical practice satisfaction, and clinical performance, respectively. The clinical thinking score was higher when their study performance was good (p<0.001), clinical practice satisfaction was higher when their major satisfaction was satisfactory (p<0.001), higher when their relationship with their clinical practice partner was good, and the clinical performance was better when the students' major satisfaction was good (p<0.001). The study performance yielded better results when their study achievement was better (p<0.05). Clinical practice satisfaction (r=0.156) and clinical performance (r=0.393) showed a positive correlation with critical thinking, and clinical performance had a positive correlation with clinical practice satisfaction. The impact factor for clinical practice satisfaction appeared to be clinical performance (p<0.05) and major satisfaction (p<0.001), and the factors impacting the clinical performance were among the sub-causes of critical thinking (p<0.05), intellectual fairness (p<0.05), watchfulness (p<0.05), clinical practice satisfaction (p<0.05), and major satisfaction (p<0.01). Conclusions: Results of the study showed that for dental hygiene students, critical thinking, clinical practice satisfaction, clinical performance, and major satisfaction were the impact factors affecting the students' clinical performance. Therefore, the study recommends that development of educational programs and operation of a field-based curriculum is necessary to improve critical thinking, clinical practice satisfaction, and major satisfaction.

• Journal of the Korean Home Economics Association
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• v.47 no.3
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• pp.103-118
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• 2009

This study was conducted to explore the factors that influence the development of happiness during childhood using longitudinal data obtained from the Korea Youth Panel Survey(KYPS). Specifically, the causal relationships between factors impacting the individual children, the home environment factor, and the happiness of children were examined over a 3-years-period. The subjects evaluated in this study included 2,844 children (1,524 boys and 1,320 girls) and 2,844 parents who were administered the KYPS. The data were analyzed using the SAS program. The results revealed that happiness that develops during childhood remains stable and constant, which indicates that prior happiness has a strong effect on future happiness. The individual factors affecting the children, which include schoolwork achievement and extra private education, were found to have a great influence on the development of happiness at all ages. The use of longitudinal data in this study is a new method in the field of Human Development.

• Journal of the Korean Society for information Management
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• v.13 no.2
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• pp.143-163
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• 1996

Relevance judgments play a very important role in evaluation of information systems since the degree of success of the information retrieval depends on the relevance judgments. This article reviews the theoretical background of the concept of 'relevance' associated with information retrieval evaluation and tries to identify whether there is any factor that affects relevance judgments. By reviewing previous researches done in the information retrieval evaluation field, four variables have been identified as impacting factors, such as document surrogates presented to judges, the order of presentation, measuring devices of relevance judgments and judges.

• Journal of Korean Public Health Nursing
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• v.31 no.1
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• pp.97-108
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• 2017

Purpose: This study was conducted to examine the correlations among nursing professionalism, major satisfaction, self leadership and ego-resilience of nursing students. Methods: The subjects were 110 nursing students recruited from one university. Data were collected using structured questionnaire, and analyzed with the SPSS/SIN 23.0 program. Results: The results indicate that nursing students have levels of nursing professionalism, major satisfaction, self leadership and ego-resilience that are higher than the median. Nursing professionalism showed differences according to plans for after graduation and subjective health status. Nursing professionalism was significantly correlated with major satisfaction, self leadership and ego-resilience. Conclusion: Major satisfaction was the most influential factor predicting greater nursing professionalism. Thus, these factors should be considered when developing a program for enhancing nursing professionalism.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1589-1593
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• 2012

Objective: To investigate liver fibrosis, TGF-${\beta}1$ levels and curative effects on hepatocellular carcinoma (HCC) with small and conventional dose perfusion chemotherapy by transcatheter arterial chemo embolization (TACE). Methods: Thirty-six hepatocellular carcinoma patients not indicated for surgical resection underwent super-selective transcatheter arterial chemoembolization, divided into small dose (n=15) and conventional dose (n=21) chemotherapy groups. Results: With conventional doses, four indices of liver fibrosis focusing on hyaluronate acide (HA), human procollagen type-III (hPC-III), collagen type-Ⅳ (Ⅳ-C) and transforming growth factor-${\beta}l$ (TGF-${\beta}1$) were obviously increased postoperative compared with preoperative (P<0.01); in contrast, with small doses there were no significant differences except for TGF-${\beta}1$. Five year survival demonstrated no significant differences between the two groups (P>0.05). Conclusion: To hepatocellular carcinoma patients treated by TACE, reducing doses of chemotherapy drugs can reduce progress of liver fibrosis, without impacting on five year survival.

• The Journal of the Korea institute of electronic communication sciences
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• v.3 no.4
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• pp.228-232
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• 2008

For the past several years, many countries have passed or have recommended legislation making it illegal to use in-hand mobile phones while driving and several manufacturers have released car kit solutions enabling hands-free operation of the mobile phone. But an automobile environment can pose extremely harsh physical conditions impacting audio quality, safety, and reliability. This article introduced a Car Kits that provided a total entertainment and telematics solution, which support all current features within the constraints of low power consumption, form factor, price, ease-of-use, manufacture ability, testability and high total quality.