Relaxor Behaviors in xBaTiO₃–(1-x)CoFe₂O₄ Materials

Cao Thi My Dung,Nhu Hoa Tran Thi,Kieu Hanh Thi Ta,Vinh Cao Tran,Bao Thu Le Nguyen,Van Hieu Le,Phuong Anh Do,Anh Tuan Dang,Heongkyu Ju,Bach Thang Phan 한국자기학회 2015 Journal of Magnetics Vol.20 No.4

Dielectric properties of xBaTiO₃–(1-x)CoFe₂O₄ composite materials have been investigated. Dielectric properties of BaTiO₃, CoFe₂O₄ and 0.5BaTiO₃–0.5CoFe₂O₄ samples show frequency dependence, which is classified as relaxor behavior with different relaxing degree. The relaxor behaviors were described using the modified Curier-Weiss and Vogel–Fulcher laws. Among three above samples, the BaTiO₃ sample has highest relaxing degree. Photoluminescence spectral indicated defects, which might in turn control relaxing degree.

Thinning and drilling laser-assisted hatching in thawed embryo transfer: A randomized controlled trial

Le, Minh Tam,Nguyen, Thi Tam An,Nguyen, Thi Thai Thanh,Nguyen, Van Trung,Le, Dinh Duong,Nguyen, Vu Quoc Huy,Cao, Ngoc Thanh,Aints, Alar,Salumets, Andres The Korean Society for Reproductive Medicine 2018 Clinical and Experimental Reproductive Medicine Vol.45 No.3

Objective: In frozen and thawed embryos, the zona pellucida (ZP) can be damaged due to hardening. Laser-assisted hatching (LAH) of embryos can increase the pregnancy rate. This study compared thinning and drilling of the ZP before frozen embryo transfer (FET). Methods: Patients were randomly allocated into two groups for LAH using thinning or drilling on day 2 after thawing. Twenty-five percent of the ZP circumference and 50% of the ZP thickness was removed in the thinning group, and a hole $40{\mu}m$ in diameter was made in the drilling group. Results: A total of 171 in vitro fertilization/intracytoplasmic sperm injection FET cycles, including 85 cycles with drilling LAH and 86 cycles with thinning LAH, were carried out. The thinning group had a similar ${\beta}$-human chorionic gonadotropin-positive rate (38.4% vs. 29.4%), implantation rate (16.5% vs. 14.4%), clinical pregnancy rate (36.0% vs. 25.9%), miscarriage rate (5.8% vs. 2.4%), ongoing pregnancy rate (30.2% vs. 23.5%), and multiple pregnancy rate (7.0% vs. 10.6%) to the drilling LAH group. There were no significant differences in pregnancy outcomes between subgroups defined based on age (older or younger than 35 years) or ZP thickness (greater or less than $17{\mu}m$) according to the LAH method. Conclusion: The present study demonstrated that partial ZP thinning or drilling resulted in similar outcomes in implantation and pregnancy rates using thawed embryos, irrespective of women's age or ZP thickness.

SERVQUAL Model in Measuring Service Quality of Sunwheel - Da Nang City

( Cao Thi Cam Huong ),( Le Thai Phuong ),( Ho Su Minh Tai ),( Le Huu Luat ) 세계문화관광학회 2016 International Journal of Culture and tourism Resea Vol.9 No.1

The purpose of the study is to measure the quality of Sun Wheel service using SERQUAL model. Sunwheel is the world`s fourth largest ferris wheel in Danang. SERVQUAL model is used to measure the gaps between Sunwheel visitor`s expectation and perceived quality in terms of tangibility, reliability, responsiveness, assurance, and empathy. Factor and multiple regression analyses were conducted on the sample of 684 customers in 2015. Findings indicate that appearance, assurance, fast service, consistency and motivation are key factors help Sunwheel increasing service quality and visitor return rate.

Dop-DenseNet: Densely Convolutional Neural Network-Based Gesture Recognition Using a Micro-Doppler Radar

Le-Hai Cao,Hoang Van-Phuc,Doan Van Sang,Le Dai Phong 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.3

Hand gesture recognition is an efficient and practical solution for the non-contact human–machine interaction in smart devices. To date, vision-based methods are widely used in this research area, but they are susceptible to light conditions. To address this issue, radar-based gesture recognition using micro-Doppler signatures can be applied as an alternative. Accordingly, the use of a novel densely convolutional neural network model, Dop-DenseNet, is proposed in this paper for improving hand gesture recognition in terms of classification accuracy and latency. The model was designed with cross or skip connections in a dense architecture so that the former features, which can be lost in the forward-propagation process, can be reused. We evaluated our model with different numbers of filter channels and experimented with it using the Dop-Net dataset, with different time lengths of input data. As a result, it was found that the model with 64 3 × 3 filters and 200 time bins of micro-Doppler spectrogram data could achieve the best performance trade-off, with 99.87% classification accuracy and 3.1 ms latency. In comparison, our model remarkably outperformed the selected state-of-the-art neural networks (GoogLeNet, Res- Net-50, NasNet-Mobile, and MobileNet-V2) using the same Dop-Net dataset.

Research on the Environmental Effects and Green Development Path of South Korean Foreign Trade

Cao Le 한국무역학회 2020 Journal of Korea trade Vol.24 No.7

Purpose - This paper aims to examine the environmental effects of South Korean foreign trade, and the changing relationship between industrial “three wastes” emissions and foreign trade. Design/methodology - Based on time series data of South Korean foreign trade and industrial “three wastes” from 2009 to 2019, a VAR model was used to analyze the long-term internal links and dynamic changes between foreign trade and environmental pollution. Findings - Variance decomposition analysis shows that for the three types of pollutants, self-impact contributes the most to the variance decomposition. It follows that South Korean foreign trade has a certain negative impact on the environment, and this impact has a certain sustainability. Originality/value - This paper contributes to the study on the relationship between foreign trade and environmental pollution. It theoretically proposes a coordinated development path for foreign trade development and green development based on the environmental impact of foreign trade, to provide a reference for the development of collaborative promotion.

The Potential and Efficiency of Aquatic Product Trade between China and South Korea

Cao Le 한국무역학회 2023 Journal of Korea trade Vol.27 No.2

Purpose – This paper assesses the trade potential and efficiency of Korea and China in the aquatic products trade. Trade efficiency and potential are the main factors that affect the growth of a country's trade. In this study, a time-varying stochastic frontier trade gravity model was constructed to analyze the trade potential and efficiency between Korea and China. By integrating the results of trade theory and empirical analysis, measures and suggestions were proposed to encourage the release of trade potential of fish exports between Korea and China. Design/methodology – In this paper, GDP per capita instead of economic size was chosen as an explanatory variable, and population size and relative distance were selected as explanatory variables to measure trade potential. For trade non-efficiency terms, regional organizations, political factors, and economic factors were mainly considered, and variables such as free trade agreements, political stability, regulatory quality, government efficiency, currency freedom, investment freedom, financial freedom, and trade freedom were selected. Panel data for South Korea and 14 aquatic products trading partners (including China) from 2002 to 2020 were used in the empirical analysis. Findings – In the past 19 years, South Korea’s export trade potential of aquatic products to China has never been lower than 70%. It was above 90% from 2006 to 2018, and has been at a high level for a long time. This shows that China’s aquatic product market has large potential for development. Originality/value – This study examines the effectiveness and potential of South Korea's exports of aquatic items to China in a methodical and comprehensive empirical manner. The evaluation of the export trade potential of South Korea's aquatic goods to China is more precise when the effects of regional organization, political, and economic variables are taken into account in the trade nonefficiency term of the stochastic frontier gravity model. At the same time, we propose to increase the scale of South Korea's aquatic products trade from the perspective of China's demand. This issue of trade studies is underexplored both empirically and in theory, although the issue has long been important to Korean and world trade.

Design and optimization of intensified biorefinery process for furfural production through a systematic procedure

Nhien, Le Cao,Long, Nguyen Van Duc,Kim, Sangyong,Lee, Moonyong Elsevier 2016 Biochemical engineering journal Vol.116 No.-

<P><B>Abstract</B></P> <P>Furfural, which is used as a precursor for the production of many other industrial chemicals, has been identified as one of the major bio-based platform chemicals that can compete with petroleum-based chemicals. On the other hand, the current commercial furfural process has a low yield and is energy-intensive. Therefore, this study develops the biorefinery production process of furfural from lignocellulosic biomass using process heat integration and process intensification. In particular, a distillation unit of the furfural production process requires considerable energy, highlighting the need to improve energy efficiency, which is the motivation of this work. An integrated and intensified distillation sequence, including an innovative bottom dividing wall column with a decanter configuration (BDWC-D) was suggested to enhance the energy and cost efficiency of the furfural production process through a comprehensive and systematic procedure that combines process intensification with heat integration. The structures of the complex columns in all sequences were optimized using the optimization method-response surface methodology (RSM). All simulations were conducted using Aspen HYSYS. The results show the proposed sequence can reduce total annual cost and carbon footprint by 10.1% and 11.6%, respectively compared to the conventional sequence.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Novel 3,4-dihydro-4-oxoquinazoline-based acetohydrazides: Design, synthesis and evaluation of antitumor cytotoxicity and caspase activation activity

Huan, Le Cong,Tran, Phuong-Thao,Phuong, Cao Viet,Duc, Phan Huy,Anh, Duong Tien,Hai, Pham The,Huong, Le Thi Thu,Thuan, Nguyen Thi,Lee, Hye Jin,Park, Eun Jae,Kang, Jong Soon,Linh, Nguyen Phuong,Hieu, Tr Elsevier 2019 Bioorganic chemistry Vol.92 No.-

<P><B>Abstract</B></P> <P>In search for novel small molecules with antitumor cytotoxicity via activating procaspase-3, we have designed and synthesized three series of novel (E)-<I>N</I>′-benzylidene-4-oxoquinazolin-3(4<I>H</I>)-yl)acetohydrazides (<B>5a-j, 6a-h,</B> and <B>7a-h)</B>. On the phenyl ring ò the benzylidene part, three different substituents, including 2-OH-4-OCH<SUB>3</SUB>, 4-OCH<SUB>3</SUB>, and 4-N(CH<SUB>3</SUB>)<SUB>2</SUB>, were introduced, respectively. Biological evaluation showed that the acetohydrazides in series <B>5a-j</B>, in which the phenyl ring of the benzylidene part was substituted by 2-OH-4-OCH<SUB>3</SUB> substituent, exhibited potent cytotoxicity against three human cancer cell lines (SW620, colon; PC-3, prostate; NCI-H23, lung). Most of the compounds, in this series, especially compounds <B>5c, 5b</B> and <B>5h,</B> also significantly activated caspase-3 activity. Among these, compound <B>5c</B> displayed 1.61-fold more potent than PAC-1 as caspase-3 activator. Cell cycle analysis showed that compounds <B>5b</B>, <B>5c</B>, and <B>5h</B> significantly arrested the cell cycle in G1 phase. Further apoptotic studies also demonstrated compounds <B>5b</B>, <B>5c</B>, and <B>5h</B> as strong apoptotic cell death inducers. The docking simulation studies showed that these compounds could activate procaspase <I>via</I> chelating Zn<SUP>2+</SUP> ion bound to the allosteric site of the zymogen.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel (<I>E</I>)-<I>N</I>′-benzylidene-2-(4-oxoquinazolin-<I>3(4H)-yl</I>)acetohydrazides were synthesized. </LI> <LI> The acetohydrazides <B>5a-i</B> exhibited potent cytotoxicity against three human cancer cell lines. </LI> <LI> A number of cytotoxic compounds exhibited good caspase activation activity. </LI> <LI> The cytotoxic compounds were shown to arrest cells at G1 phase. </LI> <LI> The cytotoxic compounds were shown as strong apoptotic inducers. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

AFM 을 이용한 2D 재료의 마찰 특성 연구

Dinh Le Cao Ky,Bien Cuong Tran Khac,정구현(K. H. Chung) 한국정밀공학회 2016 한국정밀공학회 학술발표대회 논문집 Vol.2016 No.5월

Unipolar Resistance Switching Characteristics in a Thick ZnO/Cu/ZnO Multilayer Structure

Tran Le,Hoang Cao Son Tran,Van Hieu Le,Tuan Tran,Cao Vinh Tran,Thanh Tan Vo,Mau Chien Dang,김상섭,이재찬,Bach Thang Phan 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.7

The resistance switching mechanism and the electrical conduction of thick Cu/ZnO/Cu/ZnO/Cu structures were investigated for various ZnO thicknesses (40, 80, 160, and 320 nm) when the thickness of the middle Cu layer was 2 nm. The ZnO films had a microstructure with columnar grains normal to the substrate. The switching voltages (VSET and VRESET) varied with the thickness of the ZnO layer. A symmetric electrode structure exhibited a unipolar resistance switching. The electrical transport of both high-resistance state (HRS) and low-resistance state (LRS) was Ohmic conduction, and the resistance switching mechanism was driven by the formation and the rupture of Cu conducting paths.