Improved Method for the Macroblock-Level Deblocking Scheme

Thanh Ha Le,정승원,Seung-Jin Baek,고성제 한국전자통신연구원 2011 ETRI Journal Vol.33 No.2

This paper presents a deblocking method for video compression in which the blocking artifacts are effectively extracted and eliminated based on both spatial and frequency domain operations. Firstly, we use a probabilistic approach to analyze the performance of the conventional macroblock-level deblocking scheme. Then, based on the results of the analysis, an algorithm to reduce the computational complexity is introduced. Experimental results show that the proposed algorithm outperforms the conventional video coding methods in terms of computation complexity while coding efficiency is maintained.

State Management of Transfer Pricing Activities of Foreign-Invested Enterprises in Vietnam

Ha Thanh LE,Nam Tien PHAN 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.2

The impact of State management factors on transfer pricing activities of foreign direct investment enterprises in Vietnam is examined in this study. This adds to the empirical evidence on factors affecting transfer pricing activities of foreign-invested enterprises in Vietnam. A questionnaire survey of officials directly involved in the inspection of transfer pricing activities is used as the research method. The study yielded 226 questionnaires. The author chose 210 questionnaires after deleting those that were ineligible due to a large number of blank cells. The following procedures are used to process the data from the satisfied votes: Cronbach’s Alpha test to measure the reliability of the scale; Exploratory factor analysis to break down data into smaller sets of variables to discover the underlying structure; Descriptive analysis to describe the underlying quantitative features of the data; Correlation and regression analysis to evaluate the relationship between variables with the support of SPSS 25 software. Inspection pressure, professional inspector qualifications, and inspector role, State control organization, inspector professionalism, legal corridor on transfer pricing control, macroeconomic situation, and investment environment have a positive impact on state management on transfer price operations, according to research findings. The author has provided solutions to increase the efficiency of State management on transfer pricing operations of foreign-invested businesses in Vietnam based on the research findings.

Right lumbar lymph trunk injury after right laparoscopic donor nephrectomy: a case report

Le Thanh Dung,Le Nguyen Vu,Than Van Sy,Tran Ha Phuong,Ninh Viet Khai,Dao Xuan Hai,Nguyen Quang Nghia 대한이식학회 2023 Korean Journal of Transplantation Vol.37 No.2

Laparoscopic donor nephrectomy (LDN) is increasingly popular because of its advantages over open surgery. Chyle leak after donor nephrectomy is a rare but potentially lethal complication if not treated appropriately. We describe a case of a 43-year-old female patient with no remarkable history who presented a chyle leak on day 2 after right transperitoneal LDN. Since conservative treatment failed, the patient underwent magnetic resonance imaging (MRI) and intranodal lipiodol lymphangiography, which confirmed the chyle leak from the right lumbar lymph trunk into the right renal fossa. The chyle leak was percutaneously embolized twice, on postoperative day (POD) 5 and POD 10, by a mixture of N-butyl-2-cyanoacrylate and lipiodol. The drainage fluid decreased significantly after the second embolization. The subhepatic drainage tube was withdrawn on POD 14, and the patient was discharged on POD 17. MRI lymphangiography and intranodal lipiodol lymphangiography effectively identified the chyle leak point. Percutaneous embolization seems to be a safe, effective method for treating high-output chyle leaks.

How sWOM Contribution Motivations Vary by Cosmetics and Restaurants in Vietnam

LE, Thi Thanh Ha,VO, Thanh Thu Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.10

The purpose of this study is to shed light on the driving motivations of contributing social word of mouth on social networking sites (sWOM) toward both tangible and intangible products. In order to develop a research model, this study adopts the motivation theory and TAM model. Data was collected from 904 members of the cosmetic and restaurant communities by using the snowball method. After assessing the validity of all constructs, the structural equation modeling (SEM) is used to test the proposed hypotheses. Results show that personal motivations (satisfaction, opinion leadership, self-enhancement, and economic incentives) and characteristics of sWOM (Perceived Usefulness and Ease of Use) have positive effect on exposure and engagement behaviors. Here are our specific findings, (1) customer satisfaction positively affects online interactions on SNSs such as Like or Sharing a content; (2) sWOM contribution behavior exists in two structures (Exposure and Engagement) and affects each other; (3) This study combines two groups of personal motivation and TAM to conceptualize a research model; and (4) The motivations of contributing sWOM between a specified service and product are rather similar. These findings help digital managers to understand consumers' behavioral contributions on SNSs and also provide interesting insights for marketers.

A Study on High Performance Fine-Grained Concrete Containing Rice Husk Ash

Ha Thanh Le,Sang Thanh Nguyen,Horst-Michael Ludwig 한국콘크리트학회 2014 International Journal of Concrete Structures and M Vol.8 No.4

Rice husk ash (RHA) is classified as a highly reactive pozzolan. It has a very high silica content similar to that of silica fume (SF). Using less-expensive and locally available RHA as a mineral admixture in concrete brings ample benefits to the costs, the technical properties of concrete as well as to the environment. An experimental study of the effect of RHA blending on workability, strength and durability of high performance fine-grained concrete (HPFGC) is presented. The results show that the addition of RHA to HPFGC improved significantly compressive strength, splitting tensile strength and chloride penetration resistance. Interestingly, the ratio of compressive strength to splitting tensile strength of HPFGC was lower than that of ordinary concrete, especially for the concrete made with 20 % RHA. Compressive strength and splitting tensile strength of HPFGC containing RHA was similar and slightly higher, respectively, than for HPFGC containing SF. Chloride penetration resistance of HPFGC containing 10?15 % RHA was comparable with that of HPFGC containing 10 % SF.

Understanding the COVID-19 Infodemic: Analyzing User-Generated Online Information During a COVID-19 Outbreak in Vietnam

Ha-Linh Quach,Thai Quang Pham,Ngoc-Anh Hoang,Dinh Cong Phung,Viet-Cuong Nguyen,Son Hong Le,Thanh Cong Le,Dang Hai Le,Anh Duc Dang,Duong Nhu Tran,Nghia Duy Ngu,Florian Vogt,Cong-Khanh Nguyen 대한의료정보학회 2022 Healthcare Informatics Research Vol.28 No.4

Objectives: Online misinformation has reached unprecedented levels during the coronavirus disease 2019 (COVID-19) pandemic. This study analyzed the magnitude and sentiment dynamics of misinformation and unverified information about public health interventions during a COVID-19 outbreak in Da Nang, Vietnam, between July and September 2020. Methods: We analyzed user-generated online information about five public health interventions during the Da Nang outbreak. We compared the volume, source, sentiment polarity, and engagements of online posts before, during, and after the outbreak using negative binomial and logistic regression, and assessed the content validity of the 500 most influential posts. Results: Most of the 54,528 online posts included were generated during the outbreak (n = 46,035; 84.42%) and by online newspapers (n = 32,034; 58.75%). Among the 500 most influential posts, 316 (63.20%) contained genuine information, 10 (2.00%) contained misinformation, 152 (30.40%) were non-factual opinions, and 22 (4.40%) contained unverifiable information. All misinformation posts were made during the outbreak, mostly on social media, and were predominantly negative. Higher levels of engagement were observed for information that was unverifiable (incidence relative risk [IRR] = 2.83; 95% confidence interval [CI], 1.33–0.62), posted during the outbreak (before: IRR = 0.15; 95% CI, 0.07–0.35; after: IRR = 0.46; 95% CI, 0.34-0.63), and with negative sentiment (IRR = 1.84; 95% CI, 1.23–2.75). Negatively toned posts were more likely to be misinformation (odds ratio [OR] = 9.59; 95% CI, 1.20–76.70) or unverified (OR = 5.03; 95% CI, 1.66–15.24). Conclusions: Misinformation and unverified information during the outbreak showed clustering, with social media being particularly affected. This indepth assessment demonstrates the value of analyzing online “infodemics” to inform public health responses.

Reduced Reference Quality Metric for Synthesized Virtual Views in 3DTV

Thanh Ha Le,Vuong Tung Long,Dinh Trieu Duong,정승원 한국전자통신연구원 2016 ETRI Journal Vol.38 No.6

Multi-view video plus depth (MVD) has been widely used owing to its effectiveness in three-dimensional data representation. Using MVD, color videos with only a limited number of real viewpoints are compressed and transmitted along with captured or estimated depth videos. Because the synthesized views are generated from decoded real views, their original reference views do not exist at either the transmitter or receiver. Therefore, it is challenging to define an efficient metric to evaluate the quality of synthesized images. We propose a novel metric—the reduced-reference quality metric. First, the effects of depth distortion on the quality of synthesized images are analyzed. We then employ the high correlation between the local depth distortions and local color characteristics of the decoded depth and color images, respectively, to achieve an efficient depth quality metric for each real view. Finally, the objective quality metric of the synthesized views is obtained by combining all the depth quality metrics obtained from the decoded real views. The experimental results show that the proposed quality metric correlates very well with full reference image and video quality metrics.

A new depth image quality metric using a pair of color and depth images

Le, Thanh-Ha,Jung, Seung-Won,Won, Chee Sun Springer-Verlag 2017 MULTIMEDIA TOOLS AND APPLICATIONS Vol.76 No.9

<P>Typical depth quality metrics require the ground truth depth image or stereoscopic color image pair, which are not always available in many practical applications. In this paper, we propose a new depth image quality metric which demands only a single pair of color and depth images. Our observations reveal that the depth distortion is strongly related to the local image characteristics, which in turn leads us to formulate a new distortion assessment method for the edge and non-edge pixels in the depth image. The local depth distortion is adaptively weighted using the Gabor filtered color image and added up to the global depth image quality metric. The experimental results show that the proposed metric closely approximates the depth quality metrics that use the ground truth depth or stereo color image pair.</P>

α-Glucosidase Inhibitory Activity of Phenolic Compounds Isolated from the Stems of Caesalpinia decapetala var. japonica

Le, Thi Thanh,Ha, Manh Tuan,Hoang, Le Minh,Vu, Ngoc Khanh,Kim, Jeong Ah,Min, Byung Sun The Korean Society of Pharmacognosy 2022 Natural Product Sciences Vol.28 No.3

In our study, sixteen known phenolic compounds, including quercetin (1), methyl gallate (2), caesalpiniaphenol C (3), 8S,8'S,7'R-(-)-lyoniresinol (4), 7,3',5'-trihydroxyflavanone (5), sappanchalcone (6), sappanone A (7), taxifolin (8), fisetin (9), fustin (10), (+)-catechin (11), brazilin (12), 3,4,5-trimethoxyphenyl β-ᴅ-glucopyranoside (13), 1-(2-methylbutyryl)phloroglucinol-glucopyranoside (14), (+)-epi-catechin (15), and astragalin (16) and one mixture of two conformers of protosappanin B (17/18) were isolated from the stems of Caesalpinia decapetala var. japonica. Their structures were elucidated based on a comparison of their physicochemical and spectral data with those of literature. To the best of our knowledge, this represents the first isolation of compounds 3, 4, 8, 9, and 10 from C. decapetala and compounds 13 and 14 from the Caesalpinia genus. All the isolated compounds were evaluated for their inhibitory effect against the α-glucosidase enzyme. Among them, two flavonols (1 and 9), one chalcone (6), and one homoisoflavanone (7) exhibited an inhibitory effect on α-glucosidase action with an IC₅₀ range value of 5.08-15.01 μM, stronger than that of the positive control (acarbose, IC₅₀ = 152.22 μM). Kinetic analysis revealed that compounds 1 and 9 showed non-competitive α-glucosidase inhibition, while the inhibition type was mixed for compounds 6 and 7.

Prevalence of Opisthorchis viverrini-Like Fluke Infection in Ducks in Binh Dinh Province, Central Vietnam

Thanh Thi Ha Dao,Emmanuel Nji Abatih,Thanh Thi Giang Nguyen,Ha Thi Lam Tran,Sarah Gabriel,Suzanne Smit,Phap Ngoc Le,Pierre Dorny 대한기생충학열대의학회 2016 The Korean Journal of Parasitology Vol.54 No.3