Dinh Phan Nguyen - Academia.edu (original) (raw)

Papers by Dinh Phan Nguyen

Journal of Japan Society of Civil Engineers, Ser. E2 (Materials and Concrete Structures), 2011

This study presents an investigation of the shear behavior of segmental concrete beams with drape... more This study presents an investigation of the shear behavior of segmental concrete beams with draped external tendons. Deviator force and transfer mechanism of prestressing force from an anchorage that affect the shear failure mechanism have been examined based on the results of experimental procedure and FEM with different location of deviator and inclined angle of draped tendons. The modified model proposed by authors has been extended for segmental concrete beams with draped external tendons with considering the effect of deviator force and transfer mechanism of prestressing force from the anchorage. The results from the extended modified model for draped external tendons had a good agreement with experimental results.

Lecture Notes in Computer Science, 2009

This paper presents a method which discovers the structure of given open source programs from the... more This paper presents a method which discovers the structure of given open source programs from their developer mailing lists. Our goal is to help successive developers understand the structures and the components of open source programs even if documents about them are not provided sufficiently. Our method consists of two phases: (1) producing a mapping between the source files and

Catalysis Letters, 2003

Vanadium and mixed vanadium and iron antimonates with rutile-type structures have been studied by... more Vanadium and mixed vanadium and iron antimonates with rutile-type structures have been studied by XANES at Sb L1 edge, 57Fe Mössbauer spectroscopy and ESR spectroscopy at 77 K. The results showed that both antimony and iron remained at their highest oxidation state, i.e. SbV and FeIII, whereas vanadium was present as VIII and VIV. Two types of VIV species were

A blue-green laser (450-550 nm) uses a host crystal doped with Tm.sup.3+. The Tm.sup.+ is excited... more A blue-green laser (450-550 nm) uses a host crystal doped with Tm.sup.3+. The Tm.sup.+ is excited through upconversion by a red pumping laser and an IR pumping laser to a state which transitions to a relatively lower energy level through emissions in the blue-green band, e.g., 450.20 nm at 75 K. The exciting laser may be tunable dye lasers or

Mechanisms and Machine Science, 2014

ABSTRACT We present in this paper the process allowing to create a cable-driven parallel robot (C... more ABSTRACT We present in this paper the process allowing to create a cable-driven parallel robot (CDPR) simulation within the XDE software environment in C \({+}{+}\) language. The elementary classes constituting a CDPR are shown with their constructor specificities. The winches, the pulleys, the cable fastenings and the platform are presented. The parameterization of elements such as the cable material characteristics, structure and size are detailed. An interface between the XDE cable-driven parallel robot simulator and a Matlab/Simulink controller have been developed. Inputs and outputs are exchanged between the controller and the simulated cable-driven robot, exactly as it is done with a physical robot.

Lecture Notes in Computer Science, 2012

When clustering a dataset, the right number k of clusters is not often obvious. And choosing k au... more When clustering a dataset, the right number k of clusters is not often obvious. And choosing k automatically is a complex problem. This paper first reviews existing methods for selecting the number of clusters for the algorithm. Then, an improved algorithm is presented for learning k while clustering. The algorithm is based on coefficients α, β that affect this selection. Meanwhile, a new measure is suggested to confirm the member of clusters. Finally, we evaluate the computational complexity of the algorithm, apply to real datasets and results show its efficiency.

Multimedia Content Analysis, Management, and Retrieval 2006, 2006

Extracting features is the first and one of the most crucial steps in recent image retrieval proc... more Extracting features is the first and one of the most crucial steps in recent image retrieval process. While the color features and the texture features of digital images can be extracted rather easily, the shape features and the layout features depend on reliable image segmentation. Unsupervised image segmentation, often used in image analysis, works on merely syntactical basis. That is, what an unsupervised segmentation algorithm can segment is only regions, but not objects. To obtain high-level objects, which is desirable in image retrieval, human assistance is needed. Supervised image segmentations schemes can improve the reliability of segmentation and segmentation refinement. In this paper we propose a novel interactive image segmentation technique that combines the reliability of a human expert with the precision of automated image segmentation. The iterative procedure can be considered a variation on the Blobworld algorithm introduced by Carson et al. from EECS Department, University of California, Berkeley. Starting with an initial segmentation as provided by the Blobworld framework, our algorithm, namely BlobContours, gradually updates it by recalculating every blob, based on the original features and the updated number of Gaussians. Since the original algorithm has hardly been designed for interactive processing we had to consider additional requirements for realizing a supervised segmentation scheme on the basis of Blobworld. Increasing transparency of the algorithm by applying usercontrolled iterative segmentation, providing different types of visualization for displaying the segmented image and decreasing computational time of segmentation are three major requirements which are discussed in detail.

The New Uranium Mining Boom, 2011

Surface and ground waters associated with abandoned uranium mines in the Kowary region, south-wes... more Surface and ground waters associated with abandoned uranium mines in the Kowary region, south-west Poland, has been investigated for their natural radioactivity levels. Concentrations of 238U, 234U, 226Ra, 228Ra and 222Rn isotopes were analyzed in 15 water samples collected from the old mining galleries, from Jedlica river and its inflow streams, as well as from several water supply plants in Kowary and Jelenia Gora towns. The results showed that although the protection measures against leaching of radioactive elements from the old galleries in the Kowary region have been undertaken and cultivation of the mining area had been performed, the levels of radioactivity in surface and ground waters on the study area are still relatively high.

Environmental management, Jan 15, 2015

One of the prerequisites of the REDD+ mechanism is to effectively predict business-as-usual (BAU)... more One of the prerequisites of the REDD+ mechanism is to effectively predict business-as-usual (BAU) scenarios for change in forest cover. This would enable estimation of how much carbon emission a project could potentially prevent and thus how much carbon credit should be rewarded. However, different factors like forest degradation and the lack of linearity in forest cover transitions challenge the accuracy of such scenarios. Here we predict and validate such BAU scenarios retrospectively based on forest cover changes at village and district level in North Central Vietnam. With the government's efforts to increase the forest cover, land use policies led to gradual abandonment of shifting cultivation since the 1990s. We analyzed Landsat images from 1973, 1989, 1998, 2000, and 2011 and found that the policies in the areas studied did lead to increased forest cover after a long period of decline, but that this increase could mainly be attributed to an increase in open forest and shru...

Volume 3: Advanced Composite Materials and Processing; Robotics; Information Management and PLM; Design Engineering, 2012

Serial 3R orthogonal manipulators have been studied recently and it has been proved that they can... more Serial 3R orthogonal manipulators have been studied recently and it has been proved that they can exhibit good performances in term of workspace size and kinematic properties. The aim of this work is to analyze their dynamic performances, and compare them with anthropomorphic manipulators, which are very popular in industry. Static and dynamic analyses based on the evaluation of the maximal input torques required for moving the manipulator are achieved. It is shown that, as in kinematics, the dynamic performances of the serial 3R orthogonal manipulators are better.

Doboku Gakkai Ronbunshuu E, 2010

The study presents an investigation of the shear behavior of segmental concrete beams with extern... more The study presents an investigation of the shear behavior of segmental concrete beams with external tendons considering the effect of joint opening. Joint position and prestressing force that affect the joint opening have been examined based on the results of experimental procedure and FEM. The simplified truss model with the small number of degree of freedom has been modified for segmental concrete beams with external tendons. The formulations to predict the variable angle and the thickness of struts are suggested with considering the effect of joint opening. A satisfactory prediction for the shear carrying capacity and the failure mechanism of segmental concrete beams with external tendons has been obtained.

Doboku Gakkai Ronbunshuu E, 2009

This paper describes the results of an experimental study and nonlinear finite element method in ... more This paper describes the results of an experimental study and nonlinear finite element method in order to examine the shear failure mechanism of segmental prestressed concrete beams by varying the length of segment, prestressing force and loading position. It is observed that after the opening of the segmental joints, the stiffness of such beams considerably decreases and the tendon stress is caused to increase significantly. The simplified truss model and other existing prediction methods for shear carrying capacity have been applied in this study in order to examine their applicability and accuracy. The simplified truss model can provide reasonable accuracy under the limitation of applied prestressing force.

ChemInform, 2013

ABSTRACT The title compounds (III) are obtained in reactions of α-D-glucosamine hydrochloride wit... more ABSTRACT The title compounds (III) are obtained in reactions of α-D-glucosamine hydrochloride with different substituted benzaldehydes under optimized reaction conditions.

2014 International Conference on Computer and Information Sciences (ICCOINS), 2014

A difficult problem of most clustering algorithms is how to specify the appropriate number of clu... more A difficult problem of most clustering algorithms is how to specify the appropriate number of clusters. This paper proposes an adaptive method of selecting of number of clusters in clustering process by making coefficients indicated the appropriate number of clusters. The intra-cluster coefficient reflects intra distortion of cluster through maximum distance and a mean distance of cluster's extremely marginal objects. The inter-cluster coefficient reflects distance among clusters. It is ratio between closest distance from this cluster's centre to an extremely marginal object of other cluster and mean distance from this cluster's centre to all of extremely marginal object of other cluster respectively. A new coefficient that indicates the appropriate number of clusters is build from the intra-cluster coefficient and inter-cluster coefficient. The looking for extremely marginal objects and the new coefficient are integrated in a weighted FCM algorithm and it is calculated adaptively while the weighted FCM is processing. The weighted FCM algorithm integrated new coefficient is called FCM++. We experiment with FCM++ on some data sets of UCI: Iris, Wine, Soybean-small and show encouraging results.

2013 IEEE/WIC/ACM International Joint Conferences on Web Intelligence (WI) and Intelligent Agent Technologies (IAT), 2013

In conventional Web browsing, to explore contents of interest while browsing a webpage, in many c... more In conventional Web browsing, to explore contents of interest while browsing a webpage, in many cases users need to leave that webpage and switch to external applications or other task-specific websites. To avoid switching between webpages, we present in this paper an approach to support the handling of further data and tasks added onto any browsed webpage in terms of augmented Web browsing. Without changing the existing Web contents and page-layouts, two levels of visual supports addable onto any existing webpage are suggested: (1) at micro level, visual cues encoding additional information are directly bound to particular hypermedia items, and (2) at macro level, additional visual layers are flexibly attached onto the browsed webpage. To illustrate the ideas, the Firefox add-on VizMe is developed with examples mimicking Google as a browser's extension, and to browse Web snippets with geospatial and temporal references.

Lecture Notes in Business Information Processing, 2013

The world of community integrated photo data on the Web challenges us to develop tools and techni... more The world of community integrated photo data on the Web challenges us to develop tools and techniques for the visual exploration of photos in terms of not only the imagery contents, but also the other information associated with the photos. In this paper, we investigate solutions for the visual exploration of photos in time and geospace. The three aspects of spatiotemporal photo data (which are: what - photo contents, where - geo-references, and when - time-references) are visually combined at various granularity levels to make an integrated visualization approach. In this way, we support tasks of interactively navigating and browsing through photo collections.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2011

... photons and intense laser radiation on the structural properties of carbon nanotubes DinhHoan... more ... photons and intense laser radiation on the structural properties of carbon nanotubes DinhHoang Nguyen1, Ngoc Trung Nguyen2, Duc Khue Pham1, Thi Thanh Bao Nguyen1, Viet Tiep Phung1, Duy Thang Dao1, Thanh Binh Nguyen1 and Thi Bich Vu 1 ...

Studies in Computational Intelligence, 2011

Predicting the face of an unidentified individual from its skeletal remains is a difficult matter... more Predicting the face of an unidentified individual from its skeletal remains is a difficult matter. Obviously, if the soft tissue thicknesses at every location at the skull are known, we can easily rebuild the face from the skull model. Thus, the problem turns out to be predicting the soft tissue thicknesses for any given skull. With the rapid development of the computer, different techniques are being used in the community for prediction tasks and in recent years the concept of neural networks has emerged as one of them. The principal strength of the neural network is its ability to find patterns and irregularities as well as detecting multi-dimensional non-linear connections in data. In this paper, we propose a method of applying neural networks to predict the soft tissue thicknesses for facial reconstruction. We use the distances between anthropometric locations at the skull as input, and the soft tissue thicknesses as output, as this format is suitable for many machine learning mechanisms. These data is collected and measured from candidates using the Computed Tomography (CT) technique.

2011 Third International Conference on Knowledge and Systems Engineering, 2011

Reconstructing the 3D facial model of an unidentified individual from his skull contributes consi... more Reconstructing the 3D facial model of an unidentified individual from his skull contributes considerable benefits to terms of archaeology, anthropology and forensic investigation but it is still significantly complicated matter. Computer aided system of 3D facial reconstruction based on skull has a great advantage of reduction in time consumption. Nevertheless, existing results either contain graphical artifacts or reflect incorrectly differences among reconstructed faces. In this paper, we propose a Vietnamese 3D facial reconstruction system from skull that can overcome existing problems. Machine learning is applied to CT image database of living Vietnamese to learn the relationship between skull measurements and soft tissue thicknesses. Then, the soft tissue thicknesses for each individual are calculated from his/her skull measurements. Moreover, instead of using a fixed number of dowels, extra dowels are added to deform a 3D template face, which ensures the smoothness of the 3D reconstructed face as well as represents best the characteristics of the face to be reconstructed.

2011 15th International Conference on Information Visualisation, 2011