• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.9
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• pp.3169-3185
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• 2021

The majority of students in higher education institutions are among generation Z. They have always depended on e-learning to support their learning activities. Therefore, higher education institutions should provide an attractive e-learning platform. E-learning interface design should be reviewed frequently to smoothen the interaction between students and the e-learning system. It is because interface design that fulfils generation Z students' preferences and expectations may upsurge their participation in e-learning. However, interface design has continually been condemned and turn out to be part of the problem that contributes to the failure of e-learning. Lack of consideration about generation Z students' preferences towards the interface design of e-learning is the factor that leads to these causes. Therefore, this study focused on identifying design characteristics of colour and graphic elements of e-learning from generation Z students' perception. This research involved a purposive sampling method for questionnaire among students of generation Z. The findings from this study could help e-learning developers to design the interface of e-learning that is suitable for generation Z students that will consider color and graphic as important characteristics.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.1043-1053
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• 2021

The purpose of this research is to investigate the impacts of gen-Z's perception of consumer-generated content on social media on their travel intention with the mediating role of travel motivation push and pull. An online questionnaire survey of a total of 369 samples was conducted with the participation of gen Z in the most important cities across Vietnam. The model was analyzed using Structural Equation Modeling (SEM) using AMOS program 22 to investigate model relationships and all hypotheses are significant. The findings indicated that gen Z values the usefulness of social media and they use social media for knowledge-seeking (push factor), and this leads to their intention to visit a destination. SEM analysis also reveals that gen Z tends to use social media to find accessibility to any destinations and they are motivated highly with destinations that have clear and easy access, for example, no visa requirement or neighboring destinations. As the result, they have better intentions to visit these destinations. This research will help marketers, especially marketing specialists to gain a better understanding of gen Z, thus implement better marketing techniques to target gen Z.

• Clinical and Experimental Pediatrics
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• v.61 no.7
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• pp.226-230
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• 2018

Purpose: This pilot study assessed changes in the growth plate and growth rates in children during a 6-month period. Methods: The study included 31 healthy children (17 boys, 14 girls) under evaluation for growth retardation. Height, weight, bone age, insulin like growth factor-1 (IGF-1), and insulin like growth factor binding protein 3 (IGF-BP3) were measured at baseline and after 6 months. In addition, the diameter, thickness, and volume of the femoral and tibial growth plates were measured using magnetic resonance imaging. Results: The mean bone age in boys and girls was 11.7 and 10.7 years, respectively. In boys, height (z score) (-0.2 vs. 0.0), weight (z score) (0.8 vs. 1.1), body mass index (BMI) (z score) (1.27 vs. 1.5), IGF-1 (ng/mL) (343.6 vs. 501.8), and IGF-BP3 (ng/mL) (5,088.5 vs. 5,620.0) were significantly higher after 6 months. In girls, height (z score) (-1.0 vs. -0.7), weight (z score) (-0.5 vs. 0.1), BMI (z score) (-0.02 vs. 0.3), IGF-1 (ng/mL) (329.3 vs. 524.6), and IGF-BP3 (ng/mL) (4,644.4 vs. 5,593.6) were also significantly higher after 6 months. In both sexes, the mean diameter and volume of the femoral and tibial growth plates were significantly increased 6 months later. Conclusion: No significant correlation was found between changes in the growth plate and clinical parameters in children with growth retardation in this study, other than correlations of change in femoral diameter with weight and BMI. A larger, long-term study is needed to precisely evaluate the correlation between change in the growth plate and growth.

• Journal of environmental and Sanitary engineering
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• v.9 no.2
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• pp.8-23
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• 1994

During the period from Mar., 1991 to Feb., 1992 66 tSP samples were collected by Hi volume air sampler at 1 sampling site in Seoul and the amount of concentration of 21 components(SO$_{4}$$^{2-}$, NO$_{3}$$^{-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Al, Ba, Ca, Cd, Cr, Cu, Fe, It Mg, Mn, Na, Ni, Pt Si, Ti, Zn, Zr ) were measured. And monthly and seasonal variation were surveyed and the principal component analysis( PCA ) were carried out with respect to these amount of pollutants, minimum of visibility and radiation on a horizontal surface. The total amount of soluble ion in water was high in order o(SO$_{4}$$^{2-}$> NO$_{3}$$^{-}$> N%'>Cl$^{-}$ and metal ion was high in order of Na> Ca>Si> Fe> Al> K> Mg> Zn> Pb> Cu>Ti> Mn > Ba> Cr> Zr> Ni> Cd. There was Seasonal variation in concentration for SO$_{4}$$^{2-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Na, Al, Ca, Bt Mg, Fe and Si. It was assumed that the components of the highest concentration on April were depend on yellow sand and the frequency of wind velocity and direction. As the results of PCA, the amount of pollution components was able to characterized with two principal components(Z$_{1}$, Z$_{2}$ ). The first principal components Z$_{1}$ was considered to be a factor indicating the pollutants originated from natural generation and The second principal components Z$_{2}$ was considered to be a factor indicating the pollutants originated from human work. The monthly concentration of pollutants in ISP, minimum of visibility and radiation on a horizontal surface was possible to evaluate by the use of these two principal components Z$_{1}$ and Z$_{2}$ .

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.6
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• pp.479-486
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• 2008

The objective of this study is to investigate experimentally the characteristics of pressure drop in SMX type motionless mixers. The motionless mixers used are SMX-O, SMX-H, SMXL-O and SMXL-H ones. The SMX-H and SMXL-H mixer elements have been designed to reduce the pressure drop as compared with the SMX-O and SMXL-O ones. The Reynolds number based on the bulk average properties of the water is in a range of 5000 to 13000. The pressure drops across the motionless mixers are measured and the friction factors are calculated using the pressure drop data. On the average, the friction factors of the SMX-H and SMXL-H mixers are about 8% and 15% lower than those of the SMX-O and SMXL-O ones. In addition, the proposed correlations from the experimental data for the friction factor are presented and compared with those obtained from the literature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.6
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• pp.16-28
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• 2012

This paper proposes a quasi Z-source converter(QZSC) with a diode-capacitor output filter to improve the output DC voltage boost ability. The proposed converter has the same quasi Z-source network topology compared with the conventional converter. But the proposed method is adopted a diode-capacitor filter as its output filter, since the conventional method is used an inductor-capacitor as its output filter. Under the condition of the same input-output DC voltage, the proposed method has more lower shoot-through duty ratio than the conventional method. Also, because the proposed converter has same voltage boost factor under lower shoot-through duty ratio compared with the conventional converter, the proposed converter can be operated with the lower capacitor voltage of Z-source network and the lower input current. To confirm the validity of the proposed method, PSIM simulation and a DSP based experiment were performed to acquire the output DC voltage 120[V] under the input DC voltage 80[V]. And the capacitor voltage and inductor current in Z-source network, the output voltage of each converter were compared and discussed.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.168-173
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• 2015

Use of forearm and hip joint bone density scan and find the clinical usefulness of the results that can be inferred as a result of any other region sites injured by a correction factor which if One part up. Groups of 60 patients, 10 patients by age 20-70 were composed of patients measured with the forearm and lumbar spine bone mineral density T-score and Z-score of the survey for each of the three factors that it was Find the correction factor to obtain the relationship. Bone mineral density of the correlation coefficient R = 0.8 correction factor is Y = 1.341X + 0.146. T-score of correlation coefficient R = 0.804 and the correction factor Y = 0.565X - 0.327 is Z-score of the correlation coefficient R = 0.637 correction factor Y = 0.539X - 0.225. It is regarded that there will be a clinical availability which can analogize the result of a part by using the result of the other part. It will be able to determine an auxiliary role in the clinical diagnosis. Correction factor to the equation Y = 1.341X + 0.146 is recommended.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.412-418
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• 2007

The dynamics of Zacco platypus population of upstream and downstream in the lake Hoengseong, Korea were investigated from April to October 2005. Length-weight relationship, condition factor (K) and relative condition factor $(K_n)$ of Z. platypus were compared by the study stations. The equations based on length-weight relationship in the lake Hoengseong were $Log(T_w)=-2.2s+3.18{\cdot}Log(T_L)\;(r^2=0.99)$. The result in comparison of variations of Z. platypus populations, in lake was more remain to better than in upstream and downstream them. Also the b value, assessed by Length-weight relationship in lake was 3.36, in upstream and downstream were 3.09, 3.15, respectively indicating the fish in lake better than stream. The slopes of population condition controlled by K factor also showed positive relationship. It was higher in lake environment than in stream sample, reflecting that population of Z. platypus distributed in lake Hoengseong was favorable and stable condition. The lake environment seems to be providing more favorable condition for Z. platypus population.

• Bulletin of the Korean Mathematical Society
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• v.51 no.3
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• pp.659-666
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• 2014

Let $\mathcal{A}$ be the class of analytic functions f in the open unit disk $\mathbb{U}$={z : ${\mid}z{\mid}$ < 1} with the normalization conditions $f(0)=f^{\prime}(0)-1=0$. If $f(z)=z+\sum_{n=2}^{\infty}a_nz^n$ and ${\delta}$ > 0 are given, then the $T_{\delta}$-neighborhood of the function f is defined as $$TN_{\delta}(f)\{g(z)=z+\sum_{n=2}^{\infty}b_nz^n{\in}\mathcal{A}:\sum_{n=2}^{\infty}T_n{\mid}a_n-b_n{\mid}{\leq}{\delta}\}$$, where $T=\{T_n\}_{n=2}^{\infty}$ is a sequence of positive numbers. In the present paper we investigate some problems concerning $T_{\delta}$-neighborhoods of function in various classes of analytic functions with $T=\{2^{-n}/n^2\}_{n=2}^{\infty}$. We also find bounds for $^{\delta}^*_T(A,B)$ defined by $$^{\delta}^*_T(A,B)=jnf\{{\delta}&gt;0:B{\subset}TN_{\delta}(f)\;for\;all\;f{\in}A\}$$ where A, B are given subsets of $\mathcal{A}$.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.4
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• pp.57-66
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• 2012

When typical Z-source DC/AC inverter(ZSI) is operated in high voltage gain area, because of its high duty ratio, voltage and current stress in Z-network of typical ZSI are increased. This paper proposes a new switched trans ZSI(STZSI) with two switched trans cells which consist of one trans and two diodes. To confirm the operation performance of the proposed system, the PSIM simulation is performed for typical ZSI, switched inductor ZSI and the proposed STZSI. Voltage / current stress and transient state characteristics of each method are compared under the condition of DC input voltage 100[V] and output phase voltage 66[Vrms]. As a result, we confirmed that transient state of the proposed STZSI is short compared with the conventional ZSI because the high voltage gain is obtained using the same duty ratio, also a low duty ratio is required for the same output voltage. Finally, we could know the proposed system have low voltage and current stress in Z-network compared with the conventional ZSI.