van nguyen - Academia.edu (original) (raw)

Papers by van nguyen

Research paper thumbnail of MIMO conditional integrator control for a class of nonlinear systems

This work develops a Multi-Input Multi-Output (MIMO) Conditional Integrator (CI) controller to a ... more This work develops a Multi-Input Multi-Output (MIMO) Conditional Integrator (CI) controller to a class of MIMO nonlinear systems, in the case of asymptotically constant references, motivated by airspace applications. These results are then applied to an aircraft control case and are compared by computer simulations with previous results from the literature that represent the starting point of the current paper. The obtained controller allows in a first step finite time semiglobal stability to a residual region, followed by exponential stability since entering this region.

Research paper thumbnail of Crossovers in two-dimensional variable range hopping

Physics Letters A, 1995

The crossovers from the Efros-Shklovskii behavior to the Mott behavior in two-dimensional variabl... more The crossovers from the Efros-Shklovskii behavior to the Mott behavior in two-dimensional variable-range hopping are studied. In the case of zero magnetic field a general temperature dependence of resistivity that describes the crossover observed experimentally is ...

Research paper thumbnail of Massless Dirac fermions in a graphene superlattice: a T-matrix approach

Journal of Physics-condensed Matter, 2010

Using the T-matrix approach, we study the effect of a Kronig-Penney periodic potential on the ele... more Using the T-matrix approach, we study the effect of a Kronig-Penney periodic potential on the electronic states and the transport properties of graphene. The energy band structure and the group velocity of charge carriers are calculated and discussed in detail for potentials with varying amplitudes and barrier-to-well width ratios. The periodic potential is shown to cause a resonant structure and to enhance the magnitude of the conductivity.

Research paper thumbnail of MIMO conditional integrator control for unmanned airlaunch

A Multiple Input Multiple Output (MIMO) controller based on the conditional integrator technique ... more A Multiple Input Multiple Output (MIMO) controller based on the conditional integrator technique is designed for the robust stabilization of a new satellite launching strategy called (unmanned) airlaunch. This strategy consists in using a two-stages launching system. The first stage is composed of an airplane (manned or unmanned) that carries a rocket launcher which constitute the subsequent stages. The control objective is to stabilize the aircraft in the launch phase. It is developed separately for two nonlinear motion modes of the model, the longitudinal and lateral modes, and is applied to the full multi-input multi-output model of the aircraft. The considered model is highly nonlinear, mostly as a consequence of possible large angle of attack, sideslip and roll angle. Finally, the present work illustrates through simulations the good performance of the proposed control algorithm.

Research paper thumbnail of Synthesis of Chromane Derivatives by Palladium-Catalyzed Intramolecular Allylation of Aldehydes with Allylic Acetates or Chlorides Using Indium and Indium(III) Chloride

Cheminform, 2005

For Abstract see ChemInform Abstract in Full Text.

Research paper thumbnail of Distributed Shortcut Networks: Layout-Aware Low-Degree Topologies Exploiting Small-World Effect

ABSTRACT Low communication latency becomes a main concern in highly parallel computers and superc... more ABSTRACT Low communication latency becomes a main concern in highly parallel computers and supercomputers. Random network topologies are best to achieve low average shortest path length and low diameter in hop counts between nodes and thus low communication latency. However, random topologies lead to a problem of increased aggregate cable length on a machine room floor. In this context we propose low-degree non-random topologies that exploit the small-world effect, which has been typically well modeled by some random network models. Our main idea is to carefully design a set of various-length shortcuts that keep the diameter small while maintain an economical cable length. Our experimental graph analysis showed that our proposed topology has low diameter and low average shortest path length, which is considerably better than those of a counterpart 2-D torus and is near to those of a counterpart random topology with the same average degree. Meanwhile, the proposed topology has average cable length drastically shorter than that of the counterpart random topology. Our cycle-accurate network simulation results show that the proposed topology has lower latency by 15% and almost the same throughput when compared to torus with the same degree.

Research paper thumbnail of A simhash-based scheme for locating product information from the web

... Van K. Nguyen School of Information and Communication Technology Hanoi University of Science ... more ... Van K. Nguyen School of Information and Communication Technology Hanoi University of Science and Technology vannk@soict.hut.edu.vn ... nPrices Number of words "Giá", "giá", "Price", … nPromos Number of words "khuyến mại", "khuyến mãi"… ...

Research paper thumbnail of Preparation of chitosan coated magnetic hydroxyapatite nanoparticles and application for adsorption of reactive blue 19 and Ni2+ ions

TheScientificWorldJournal, 2014

An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared ... more An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared with the purpose of improvement for the removal of Ni 2+ ions and textile dye by coprecipitation. Structure and properties of CS-MHAP were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Weight percent of chitosan was investigated by thermal gravimetric analysis (TGA). The prepared CS-MHAP presents a significant improvement on the removal efficiency of Ni 2+ ions and reactive blue 19 dye (RB19) in comparison with chitosan and magnetic hydroxyapatite nanoparticles. Moreover, the adsorption capacities were affected by several parameters such as contact time, initial concentration, adsorbent dosage, and initial pH. Interestingly, the prepared adsorbent could be easily recycled from an aqueous solution by an external magnet and reused for adsorption with high removal efficiency.

Research paper thumbnail of Effects of Maillard Reaction Products on the Oxidative Cleavage and Polymerization of Protein under Ascorbic Acid-Transition Metal System

Bioscience Biotechnology and Biochemistry, 1999

This study investigated the effects of Maillard reaction products (MRPs) on the oxidative cleavag... more This study investigated the effects of Maillard reaction products (MRPs) on the oxidative cleavage and polymerization of BSA (bovine serum albumin) in an aqueous system. In L-ascorbic acid (AsA) and Cu(II) or Fe(III) reaction system, 50-60% of BSA was cleaved under physiological conditions (37 degrees C, pH 7.2). The oxidative cleavage induced by AsA-Cu(II) system was suppressed to the extent of 32-86% by model melanoidins or brown pigments from amino acids and foodstuffs. In the AsA-Fe(III) system, the oxidative cleavage was inhibited to the extent of 45-93% by melanoidins and brown pigments. However, this cleavage was promoted by amino acid Amadori rearrangement products and brown pigment from soy paste. Therefore, MRPs show both suppression and promotion activity on oxidative cleavage of BSA in the system of AsA and a transition metal. The quantity of Amadori rearrangement moiety (ARM) in melanoidins from Lysine and brown pigments molecules from foods was also measured. From these data, it was estimated that the suppression and/or promotion of oxidative cleavage of BSA did not only depend on the quantity of ARM, but also depended on the chemical structure of ARM in melanoidins or brown pigments.

Research paper thumbnail of Desmutagenicity of Soybean after Heating

Bioscience Biotechnology and Biochemistry, 1996

The mutagenicity and desmutagenicity of extracts of soybeans heated at 225 +/- 5 degrees C were i... more The mutagenicity and desmutagenicity of extracts of soybeans heated at 225 +/- 5 degrees C were investigated by the Ames test. The soybeans were refluxed in water, methanol, or diethylether for 2 h. The aqueous and methanol extracts (2-4 mg/plate) of the heated soybeans exhibited strong desmutagenic activity of 43-92% against heterocyclic amines (Trp-P-1. Glu-P-2, IQ, MeIQx. PhIP), while no mutagenicity was observed. The desmutagenicity of the heated soybean extracts remained even after denaturation by 0.1 N HCl in vitro and absorption by the rat small intestine. The desmutagenic mechanism for heated soybeans was evaluated, and it was verified that the soybean extract exhibited its desmutagenicity by blocking the mutagenicity of activated Trp-P-1, and not by inhibiting the S9 enzyme system.

Research paper thumbnail of Electronic band structures of graphene nanoribbons with self-passivating edge reconstructions

Journal of Physics-condensed Matter, 2011

Using the nearest-neighbor tight-binding approach we study the electronic band structures of grap... more Using the nearest-neighbor tight-binding approach we study the electronic band structures of graphene nanoribbons with self-passivating edge reconstructions. For zigzag ribbons the edge reconstruction moves both the Fermi energy and the flat band down by several hundred meV, and the flat band is always found to be below the Fermi energy. The states featured by the flat band are shown to be mainly localized at the atoms belonging to several lattice lines closest to the edges. For armchair ribbons the edge reconstruction strongly modifies the band structure in the region close to the Fermi energy, leading to the appearance of a band gap even for ribbons which were predicted to be metallic in the model of standard armchair edges. The gap widths are, however, strongly different in magnitude and behave in different ways regarding the ribbon width.

Research paper thumbnail of Electronic cash: cryptography & distributed systems

... Author. Van Khanh Nguyen, University of Wollongong. ... Recommended Citation. Nguyen, VanKhan... more ... Author. Van Khanh Nguyen, University of Wollongong. ... Recommended Citation. Nguyen, VanKhanh, Electronic cash: cryptography & distributed systems, Master of Science (Hons.) thesis, School of Information Technology and Computer Science, University of Wollongong, 1997. ...

Research paper thumbnail of Precoder Design for DSTM based on Statistical Information the Fading Cannels

Vehicular Technology, IEEE Conference, 2006

This paper addresses the problem of designing a linear precoder for differential space-time coded... more This paper addresses the problem of designing a linear precoder for differential space-time coded communication systems in spatially correlated Rayleigh fading channels. Based on the pairwise error probability upper bound of the differential space-time modulation (DSTM) scheme, we derive a precoder that can exploit the spatial correlation of the channels. Simulation results illustrate that a significant performance gain can be achieved by using the designed precoder

Research paper thumbnail of Performance Analysis of the Differential Space-Time Modulation in Time-Varying Rayleigh Faing Channels

Vehicular Technology, IEEE Conference, 2006

Differential space-time modulation (DSTM) is an encoding technique for multiantenna systems that ... more Differential space-time modulation (DSTM) is an encoding technique for multiantenna systems that allows the receiver to detect the transmitted signals without the knowledge of the fading channels. It can be viewed as an extension of the differential phase-shift keying (DPSK) scheme in single antenna systems. In this paper, the performance of the DSTM is analyzed. By using the moment-generating function-based

Research paper thumbnail of Single-walled carbon nanotubes synthesized by chemical vapor deposition of C2H2 over an Al2O3 supported mixture of Fe, Mo, Co catalysts

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2011

Single-walled carbon nanotubes (SWCNTs) have been successfully synthesized by chemical vapor depo... more Single-walled carbon nanotubes (SWCNTs) have been successfully synthesized by chemical vapor deposition (CVD) using acetylene (C 2 H 2 ) gas as a carbon source and a mixture of Fe/Mo/Co on an Al 2 O 3 support as a catalyst. The effects of the weight percentage (wt%) of metals in the Fe/Mo/Co/Al 2 O 3 catalysts, growth time, gas flow rate and growth temperature on SWCNT growth were studied in detail. The optimum growth conditions were found to be a growth time of 60 min, a growth temperature of 750 • C, Ar/H 2 /C 2 H 2 flow rates of 420/100/14 sccm and a catalyst composition of Fe/Mo/Co/Al 2 O 3 = 5/3/1/80 (wt%). The morphologies and structures of the grown SWCNTs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy techniques.

Research paper thumbnail of Variable range hopping in finite one-dimensional and anisotropic two-dimensional systems

Physica B-condensed Matter, 2003

The variable range hopping conduction is simulated in a strongly anisotropic two-dimensional (2D)... more The variable range hopping conduction is simulated in a strongly anisotropic two-dimensional (2D) percolation model, which consists of parallel conducting chains coupled to each other weakly via rare “impurities”. The exponential temperature dependence of resistance has been calculated for samples of different size, interchain distance, and impurity concentration in two directions, longitudinal and perpendicular to the chain direction. In the limiting case of single finite chains the results are in good agreement with existing analytical expressions for both the length and temperature dependences, but with a low temperature limit, depending on the chain length and localization length. In the 2D case it was shown that there exists a crossover in relative behaviour between the longitudinal and transverse resistance of a finite system, which however disappears from the limit of infinite systems, where the hopping conduction should be always isotropic and obeys the 2D Mott law.

Research paper thumbnail of Fabrication of horizontally aligned ultra-long single-walled carbon nanotubes on Si substrates using the fast-heating chemical vapor deposition method

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this paper we study the growth of horizontally aligned ultra-long single-walled carbon nanotub... more In this paper we study the growth of horizontally aligned ultra-long single-walled carbon nanotubes (SWCNTs) (5 mm) on oxidized silicon substrates by the fast-heating chemical vapor deposition (CVD) method. Ferric chloride (FeCl 3 ) and ethanol (C 2 H 5 OH) solution are used as catalyst and carbon source, respectively. The influence of growth conditions such as temperature, time and gas flow rates on the SWCNTs' growth is studied in detail. The morphologies and structure of the SWCNTs are analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The experimental results demonstrate that by fast-heating CVD of ethanol at a temperature of 900 • C for 60 min, the SWCNTs have high quality. They are clean, ultra-long (mm), highly dense and as straight as parallel lines.

Research paper thumbnail of Structural Organization and Chromosomal Localization of a Human Gene (HIP/PAP) Encoding a C-type Lectin Overexpressed in Primary Liver Cancer

European Journal of Biochemistry, 1994

We previously identified, through differential screening of a human primary liver cancer library,... more We previously identified, through differential screening of a human primary liver cancer library, a novel gene (named HIP)the expression of which is markedly increased in 25% of human primary liver cancers. HIP mRNA expression is tissue specific since it is restricted to pancreas and small intestine. HIP protein consists in a signal peptide linked to a carbohydrate-recognition domain (CRD), typical of C-type lectins without other binding domains. We have proposed that HIP and related proteins belong to a new family of C-type lectins. Drickamer [Drickamer, K. (1993) Curr Opin. Struct. Biol. 3, 393–400] included this group of proteins in his classification of C-type lectins as the free CRD (group VII) lectins. In the present report we describe the genomic organization and the chromosomal localization of HIP. We have shown that HIP is in fact the pancreatitis-associated protein (PAP) and provided a phylogenetic analysis of the free CRD lectins. Furthermore, the analysis of HIP/PAP gene indicates that the HIP/PAP CRD is encoded by four exons, a pattern shared with all members of this group of proteins. This common intron-exon organization indicates an ancient divergence of the free CRD-lectin group from other groups of C-type lectins. We provide evidence for the localization of HIP/PAP on chromosome 2, suggesting previous duplication of HIP/PAP and the related reg Iα and reg Iβ genes from the same ancestral gene. Finally, the sequence of the 5′ upstream region of the HIP gene shows several potential regulatory elements which might account for the enhanced expression of the gene during pancreatic inflammation and liver carcinogenesis.

Research paper thumbnail of Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone)

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2010

Page 1. Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene gl... more Page 1. Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone) This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2010 Adv. Nat. Sci: Nanosci. Nanotechnol. 1 025012 ...

Research paper thumbnail of The prevalence and genetic diversity of group A rotaviruses on pig farms in the Mekong Delta region of Vietnam

Veterinary Microbiology, 2014

Research paper thumbnail of MIMO conditional integrator control for a class of nonlinear systems

This work develops a Multi-Input Multi-Output (MIMO) Conditional Integrator (CI) controller to a ... more This work develops a Multi-Input Multi-Output (MIMO) Conditional Integrator (CI) controller to a class of MIMO nonlinear systems, in the case of asymptotically constant references, motivated by airspace applications. These results are then applied to an aircraft control case and are compared by computer simulations with previous results from the literature that represent the starting point of the current paper. The obtained controller allows in a first step finite time semiglobal stability to a residual region, followed by exponential stability since entering this region.

Research paper thumbnail of Crossovers in two-dimensional variable range hopping

Physics Letters A, 1995

The crossovers from the Efros-Shklovskii behavior to the Mott behavior in two-dimensional variabl... more The crossovers from the Efros-Shklovskii behavior to the Mott behavior in two-dimensional variable-range hopping are studied. In the case of zero magnetic field a general temperature dependence of resistivity that describes the crossover observed experimentally is ...

Research paper thumbnail of Massless Dirac fermions in a graphene superlattice: a T-matrix approach

Journal of Physics-condensed Matter, 2010

Using the T-matrix approach, we study the effect of a Kronig-Penney periodic potential on the ele... more Using the T-matrix approach, we study the effect of a Kronig-Penney periodic potential on the electronic states and the transport properties of graphene. The energy band structure and the group velocity of charge carriers are calculated and discussed in detail for potentials with varying amplitudes and barrier-to-well width ratios. The periodic potential is shown to cause a resonant structure and to enhance the magnitude of the conductivity.

Research paper thumbnail of MIMO conditional integrator control for unmanned airlaunch

A Multiple Input Multiple Output (MIMO) controller based on the conditional integrator technique ... more A Multiple Input Multiple Output (MIMO) controller based on the conditional integrator technique is designed for the robust stabilization of a new satellite launching strategy called (unmanned) airlaunch. This strategy consists in using a two-stages launching system. The first stage is composed of an airplane (manned or unmanned) that carries a rocket launcher which constitute the subsequent stages. The control objective is to stabilize the aircraft in the launch phase. It is developed separately for two nonlinear motion modes of the model, the longitudinal and lateral modes, and is applied to the full multi-input multi-output model of the aircraft. The considered model is highly nonlinear, mostly as a consequence of possible large angle of attack, sideslip and roll angle. Finally, the present work illustrates through simulations the good performance of the proposed control algorithm.

Research paper thumbnail of Synthesis of Chromane Derivatives by Palladium-Catalyzed Intramolecular Allylation of Aldehydes with Allylic Acetates or Chlorides Using Indium and Indium(III) Chloride

Cheminform, 2005

For Abstract see ChemInform Abstract in Full Text.

Research paper thumbnail of Distributed Shortcut Networks: Layout-Aware Low-Degree Topologies Exploiting Small-World Effect

ABSTRACT Low communication latency becomes a main concern in highly parallel computers and superc... more ABSTRACT Low communication latency becomes a main concern in highly parallel computers and supercomputers. Random network topologies are best to achieve low average shortest path length and low diameter in hop counts between nodes and thus low communication latency. However, random topologies lead to a problem of increased aggregate cable length on a machine room floor. In this context we propose low-degree non-random topologies that exploit the small-world effect, which has been typically well modeled by some random network models. Our main idea is to carefully design a set of various-length shortcuts that keep the diameter small while maintain an economical cable length. Our experimental graph analysis showed that our proposed topology has low diameter and low average shortest path length, which is considerably better than those of a counterpart 2-D torus and is near to those of a counterpart random topology with the same average degree. Meanwhile, the proposed topology has average cable length drastically shorter than that of the counterpart random topology. Our cycle-accurate network simulation results show that the proposed topology has lower latency by 15% and almost the same throughput when compared to torus with the same degree.

Research paper thumbnail of A simhash-based scheme for locating product information from the web

... Van K. Nguyen School of Information and Communication Technology Hanoi University of Science ... more ... Van K. Nguyen School of Information and Communication Technology Hanoi University of Science and Technology vannk@soict.hut.edu.vn ... nPrices Number of words "Giá", "giá", "Price", … nPromos Number of words "khuyến mại", "khuyến mãi"… ...

Research paper thumbnail of Preparation of chitosan coated magnetic hydroxyapatite nanoparticles and application for adsorption of reactive blue 19 and Ni2+ ions

TheScientificWorldJournal, 2014

An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared ... more An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared with the purpose of improvement for the removal of Ni 2+ ions and textile dye by coprecipitation. Structure and properties of CS-MHAP were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Weight percent of chitosan was investigated by thermal gravimetric analysis (TGA). The prepared CS-MHAP presents a significant improvement on the removal efficiency of Ni 2+ ions and reactive blue 19 dye (RB19) in comparison with chitosan and magnetic hydroxyapatite nanoparticles. Moreover, the adsorption capacities were affected by several parameters such as contact time, initial concentration, adsorbent dosage, and initial pH. Interestingly, the prepared adsorbent could be easily recycled from an aqueous solution by an external magnet and reused for adsorption with high removal efficiency.

Research paper thumbnail of Effects of Maillard Reaction Products on the Oxidative Cleavage and Polymerization of Protein under Ascorbic Acid-Transition Metal System

Bioscience Biotechnology and Biochemistry, 1999

This study investigated the effects of Maillard reaction products (MRPs) on the oxidative cleavag... more This study investigated the effects of Maillard reaction products (MRPs) on the oxidative cleavage and polymerization of BSA (bovine serum albumin) in an aqueous system. In L-ascorbic acid (AsA) and Cu(II) or Fe(III) reaction system, 50-60% of BSA was cleaved under physiological conditions (37 degrees C, pH 7.2). The oxidative cleavage induced by AsA-Cu(II) system was suppressed to the extent of 32-86% by model melanoidins or brown pigments from amino acids and foodstuffs. In the AsA-Fe(III) system, the oxidative cleavage was inhibited to the extent of 45-93% by melanoidins and brown pigments. However, this cleavage was promoted by amino acid Amadori rearrangement products and brown pigment from soy paste. Therefore, MRPs show both suppression and promotion activity on oxidative cleavage of BSA in the system of AsA and a transition metal. The quantity of Amadori rearrangement moiety (ARM) in melanoidins from Lysine and brown pigments molecules from foods was also measured. From these data, it was estimated that the suppression and/or promotion of oxidative cleavage of BSA did not only depend on the quantity of ARM, but also depended on the chemical structure of ARM in melanoidins or brown pigments.

Research paper thumbnail of Desmutagenicity of Soybean after Heating

Bioscience Biotechnology and Biochemistry, 1996

The mutagenicity and desmutagenicity of extracts of soybeans heated at 225 +/- 5 degrees C were i... more The mutagenicity and desmutagenicity of extracts of soybeans heated at 225 +/- 5 degrees C were investigated by the Ames test. The soybeans were refluxed in water, methanol, or diethylether for 2 h. The aqueous and methanol extracts (2-4 mg/plate) of the heated soybeans exhibited strong desmutagenic activity of 43-92% against heterocyclic amines (Trp-P-1. Glu-P-2, IQ, MeIQx. PhIP), while no mutagenicity was observed. The desmutagenicity of the heated soybean extracts remained even after denaturation by 0.1 N HCl in vitro and absorption by the rat small intestine. The desmutagenic mechanism for heated soybeans was evaluated, and it was verified that the soybean extract exhibited its desmutagenicity by blocking the mutagenicity of activated Trp-P-1, and not by inhibiting the S9 enzyme system.

Research paper thumbnail of Electronic band structures of graphene nanoribbons with self-passivating edge reconstructions

Journal of Physics-condensed Matter, 2011

Using the nearest-neighbor tight-binding approach we study the electronic band structures of grap... more Using the nearest-neighbor tight-binding approach we study the electronic band structures of graphene nanoribbons with self-passivating edge reconstructions. For zigzag ribbons the edge reconstruction moves both the Fermi energy and the flat band down by several hundred meV, and the flat band is always found to be below the Fermi energy. The states featured by the flat band are shown to be mainly localized at the atoms belonging to several lattice lines closest to the edges. For armchair ribbons the edge reconstruction strongly modifies the band structure in the region close to the Fermi energy, leading to the appearance of a band gap even for ribbons which were predicted to be metallic in the model of standard armchair edges. The gap widths are, however, strongly different in magnitude and behave in different ways regarding the ribbon width.

Research paper thumbnail of Electronic cash: cryptography & distributed systems

... Author. Van Khanh Nguyen, University of Wollongong. ... Recommended Citation. Nguyen, VanKhan... more ... Author. Van Khanh Nguyen, University of Wollongong. ... Recommended Citation. Nguyen, VanKhanh, Electronic cash: cryptography & distributed systems, Master of Science (Hons.) thesis, School of Information Technology and Computer Science, University of Wollongong, 1997. ...

Research paper thumbnail of Precoder Design for DSTM based on Statistical Information the Fading Cannels

Vehicular Technology, IEEE Conference, 2006

This paper addresses the problem of designing a linear precoder for differential space-time coded... more This paper addresses the problem of designing a linear precoder for differential space-time coded communication systems in spatially correlated Rayleigh fading channels. Based on the pairwise error probability upper bound of the differential space-time modulation (DSTM) scheme, we derive a precoder that can exploit the spatial correlation of the channels. Simulation results illustrate that a significant performance gain can be achieved by using the designed precoder

Research paper thumbnail of Performance Analysis of the Differential Space-Time Modulation in Time-Varying Rayleigh Faing Channels

Vehicular Technology, IEEE Conference, 2006

Differential space-time modulation (DSTM) is an encoding technique for multiantenna systems that ... more Differential space-time modulation (DSTM) is an encoding technique for multiantenna systems that allows the receiver to detect the transmitted signals without the knowledge of the fading channels. It can be viewed as an extension of the differential phase-shift keying (DPSK) scheme in single antenna systems. In this paper, the performance of the DSTM is analyzed. By using the moment-generating function-based

Research paper thumbnail of Single-walled carbon nanotubes synthesized by chemical vapor deposition of C2H2 over an Al2O3 supported mixture of Fe, Mo, Co catalysts

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2011

Single-walled carbon nanotubes (SWCNTs) have been successfully synthesized by chemical vapor depo... more Single-walled carbon nanotubes (SWCNTs) have been successfully synthesized by chemical vapor deposition (CVD) using acetylene (C 2 H 2 ) gas as a carbon source and a mixture of Fe/Mo/Co on an Al 2 O 3 support as a catalyst. The effects of the weight percentage (wt%) of metals in the Fe/Mo/Co/Al 2 O 3 catalysts, growth time, gas flow rate and growth temperature on SWCNT growth were studied in detail. The optimum growth conditions were found to be a growth time of 60 min, a growth temperature of 750 • C, Ar/H 2 /C 2 H 2 flow rates of 420/100/14 sccm and a catalyst composition of Fe/Mo/Co/Al 2 O 3 = 5/3/1/80 (wt%). The morphologies and structures of the grown SWCNTs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy techniques.

Research paper thumbnail of Variable range hopping in finite one-dimensional and anisotropic two-dimensional systems

Physica B-condensed Matter, 2003

The variable range hopping conduction is simulated in a strongly anisotropic two-dimensional (2D)... more The variable range hopping conduction is simulated in a strongly anisotropic two-dimensional (2D) percolation model, which consists of parallel conducting chains coupled to each other weakly via rare “impurities”. The exponential temperature dependence of resistance has been calculated for samples of different size, interchain distance, and impurity concentration in two directions, longitudinal and perpendicular to the chain direction. In the limiting case of single finite chains the results are in good agreement with existing analytical expressions for both the length and temperature dependences, but with a low temperature limit, depending on the chain length and localization length. In the 2D case it was shown that there exists a crossover in relative behaviour between the longitudinal and transverse resistance of a finite system, which however disappears from the limit of infinite systems, where the hopping conduction should be always isotropic and obeys the 2D Mott law.

Research paper thumbnail of Fabrication of horizontally aligned ultra-long single-walled carbon nanotubes on Si substrates using the fast-heating chemical vapor deposition method

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2012

In this paper we study the growth of horizontally aligned ultra-long single-walled carbon nanotub... more In this paper we study the growth of horizontally aligned ultra-long single-walled carbon nanotubes (SWCNTs) (5 mm) on oxidized silicon substrates by the fast-heating chemical vapor deposition (CVD) method. Ferric chloride (FeCl 3 ) and ethanol (C 2 H 5 OH) solution are used as catalyst and carbon source, respectively. The influence of growth conditions such as temperature, time and gas flow rates on the SWCNTs' growth is studied in detail. The morphologies and structure of the SWCNTs are analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The experimental results demonstrate that by fast-heating CVD of ethanol at a temperature of 900 • C for 60 min, the SWCNTs have high quality. They are clean, ultra-long (mm), highly dense and as straight as parallel lines.

Research paper thumbnail of Structural Organization and Chromosomal Localization of a Human Gene (HIP/PAP) Encoding a C-type Lectin Overexpressed in Primary Liver Cancer

European Journal of Biochemistry, 1994

We previously identified, through differential screening of a human primary liver cancer library,... more We previously identified, through differential screening of a human primary liver cancer library, a novel gene (named HIP)the expression of which is markedly increased in 25% of human primary liver cancers. HIP mRNA expression is tissue specific since it is restricted to pancreas and small intestine. HIP protein consists in a signal peptide linked to a carbohydrate-recognition domain (CRD), typical of C-type lectins without other binding domains. We have proposed that HIP and related proteins belong to a new family of C-type lectins. Drickamer [Drickamer, K. (1993) Curr Opin. Struct. Biol. 3, 393–400] included this group of proteins in his classification of C-type lectins as the free CRD (group VII) lectins. In the present report we describe the genomic organization and the chromosomal localization of HIP. We have shown that HIP is in fact the pancreatitis-associated protein (PAP) and provided a phylogenetic analysis of the free CRD lectins. Furthermore, the analysis of HIP/PAP gene indicates that the HIP/PAP CRD is encoded by four exons, a pattern shared with all members of this group of proteins. This common intron-exon organization indicates an ancient divergence of the free CRD-lectin group from other groups of C-type lectins. We provide evidence for the localization of HIP/PAP on chromosome 2, suggesting previous duplication of HIP/PAP and the related reg Iα and reg Iβ genes from the same ancestral gene. Finally, the sequence of the 5′ upstream region of the HIP gene shows several potential regulatory elements which might account for the enhanced expression of the gene during pancreatic inflammation and liver carcinogenesis.

Research paper thumbnail of Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone)

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2010

Page 1. Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene gl... more Page 1. Formation of nanoparticles in aqueous solution from poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone) This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2010 Adv. Nat. Sci: Nanosci. Nanotechnol. 1 025012 ...

Research paper thumbnail of The prevalence and genetic diversity of group A rotaviruses on pig farms in the Mekong Delta region of Vietnam

Veterinary Microbiology, 2014