Selective Deep Convolutional Features for Image Retrieval

Convolutional Neural Network (CNN) is a very powerful approach to extract discriminative local descriptors for effective image search. Recent work adopts fine-tuned strategies to further improve the discriminative power of the descriptors. Taking a different approach, in this paper, we propose a novel framework to achieve competitive retrieval performance. Firstly, we propose various masking schemes, namely SIFT-mask, SUM-mask, and MAX-mask, to select a representative subset of local convolutional features and remove a large number of redundant features. We demonstrate that this can effectively address the burstiness issue and improve retrieval accuracy. Secondly, we propose to employ recent embedding and aggregating methods to further enhance feature discriminability. Extensive experiments demonstrate that our proposed framework achieves state-of-the-art retrieval accuracy.Comment: Accepted to ACM MM 201

Assessment of High School Students’ Learning and Development of Qualities and Competencies: A Case Study

This study aims to assess high school students' learning outcomes, their achievement of goals and fulfilling academic requirements and how the entire teaching and learning process takes place. The study, consisting of an experimental group and a control group was conducted for pre-test and post-test comparisons of the academic performance of 88 10th grade students. 44 students were selected as the experimental group that underwent a specific teaching strategy to monitor their development of qualities and competencies in one semester, and the remaining 44 students acted as the control group. The data collected after the tests were analyzed using SPSS software (V20). The results showed that the students in the experimental group had better academic results than those in the control group. The findings of this study have implications for policy, further research as well as approaches for the assessment of students’ development of qualities and competencies in Vietnam

Phrasal semantic distance for vietnamese textual document retrieval

In this paper, a computational semantic method is proposed to estimate the phrasal semantic distance used in our model of a Vietnamese document retrieval system. The semantic distances between phrases are defined in terms of semantic classes and semantic relations to ensure that it can reflect how different two certain phrases are. To estimate the semantic distance, the semantic classes of a phase are identified by using the n-gram model. After identification of the semantic classes, their semantic relations are also identified by using a Vietnamese Lexicon Ontology. This handcrafted ontology contains defined semantic classes and their potential relations in Vietnamese language explicitly. For the evaluation purpose, a phrasal semantic retrieval system has been built to test with a data set of 720 phrases and 30 queries. The evaluation shows the precision of 96.6% and the recall of 78.4% on experimental results

Synthesis and Investigation of the Physical Properties of Lead-Free BCZT Ceramics

This work presents the structure, microstructure, and physical properties of low sintering temperature lead-free ceramics 0.52(Ba0.7Ca0.3)TiO3-0.48Ba(Zr0.2Ti0.8)O3 doped with nano-sized ZnO particles (noted as BCZT/x, x is the content of ZnO nanoparticles in wt.%, x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.25). The obtained results of Raman scattering and dielectric measurements have confirmed that Zn2+ has occupied B-site, to cause a deformation in the ABO3-type lattice of the BCZT/x specimens. The 0.15 wt.% ZnO-modified ceramic sintered at 1350°C exhibited excellent piezoelectric parameters: d33 = 420 pC/N, d31 = −174 pC/N, kp = 0.483, kt = 0.423, and k33 = 0.571. The obtained results indicate that the high-quality lead-free BCZT ceramic could be successfully synthesized at a low sintering temperature of 1350°C with an addition of appropriated amount of ZnO nanoparticles. This work also reports the influence of the sintering temperature on structure, microstructure, and piezoelectric properties of BCZT/0.15 compound. By rising sintering temperature, the piezoelectric behaviors were improved and rose up to the best parameters at a sintering temperature of 1450°C (d33 = 576 pC/N and kp = 0.55). The corresponding properties of undoped BCZT ceramics were investigated as a comparison. It also presented that the sintering behavior and piezo-parameters of doped BCZT samples are better than the undoped BCZT samples at each sintering temperature

Influence Of Fabrication Condition on the Microstructural and Optical Properties of Lead-Free Ferroelectric Bi0.5_{0.5}Na0.5_{0.5}TiO3_{3} Materials

Lead-free ferroelectric materials have attracted considerable attention due to the increasing potential application in environmental benign materials. Among lead-free ferroelectric materials, the Bi0.5Na0.5TiO3 (BNT) materials were more studied because it exhibited the good ferroelectric and piezoelectric properties which could be promising candidate materials replacing Pb(Zr,Ti)O3. In this work, the lead-free ferroelectric BNT materials were synthesized by sol-gel method. The effects of fabrication process to microstructural and optical properties were studied which includes Na precursor concentration and calcining temperature. The result indicated that the Na precursor concentration were higher 40 mol.% and the calcining temperature

The Correlation between the Structures of the Nasal Tip on the Ultrasound and the Anthropometry of the Nose in Vietnamese

BACKGROUND: Nowadays, there are few types of research held in Vietnam to investigate the anthropometric index of the nose as well as analysis the structure of nasal tip on ultrasound to identify the relationship between these parameters. AIM: determine the relationship between the height and the width of the nasal tip and the structures constructed these areas by anthropometric and ultrasound measurement. METHODS: a descriptive study in Thanh Van Hospital from December 2017 to April 2019. RESULTS: There were 94 women (62.7%), and 56 men (37.3%) and the average age were 33.6 years old. The height and width of the nasal tip are 10.1 mm and 21.7 mm, respectively. Through the ultrasound, the thickness of the adipose tissues is 3 mm. The width of the interdomal fat pad is 6.5 mm and the distance between two tip point is 5.6 mm. There are the relationships between the distance of two tip points and the width of the tip (r = 0.341), and the width of the interdomal fat pad (r = 0.72). There is also the correlation between the width of the nasal tip with the distance of two tip points (r = 0.46) and the height of the tip with the thickness of the interdomal fat pad (r = 1.23). CONCLUSION: The thickness of the interdomal fat affects the height of the tip, and the distance of two tip points influences the width of the tip