Nguyen Trong Tan (K17 HCM) (original) (raw)

Papers by Nguyen Trong Tan (K17 HCM)

Research paper thumbnail of Building a Chatbot System to Analyze Opinions of English Comments

Informatics and Automation

Chatbot research has advanced significantly over the years. Enterprises have been investigating h... more Chatbot research has advanced significantly over the years. Enterprises have been investigating how to improve these tools’ performance, adoption, and implementation to communicate with customers or internal teams through social media. Besides, businesses also want to pay attention to quality reviews from customers via social networks about products available in the market. From there, please select a new method to improve the service quality of their products and then send it to publishing agencies to publish based on the needs and evaluation of society. Although there have been numerous recent studies, not all of them address the issue of opinion evaluation on the chatbot system. The primary goal of this paper’s research is to evaluate human comments in English via the chatbot system. The system’s documents are preprocessed and opinion-matched to provide opinion judgments based on English comments. Based on practical needs and social conditions, this methodology aims to evolve cha...

Research paper thumbnail of Changes in Community Composition of Tropical Evergreen Forests during Succession in Ta Dung National Park, Central Highlands of Vietnam

Forests, 2020

Degradation of tropical forests is a major driver of the global extinction crisis. A key question... more Degradation of tropical forests is a major driver of the global extinction crisis. A key question is understanding the role of evolution history during forest succession in the context of forest restoration for maintaining ecosystem function and stability. This study was conducted in a fragmented forest landscape in the central highlands of Vietnam. We sampled living trees with diameters at breast height of ≥6.0 cm in nineteen 0.25 ha plots to evaluate forest community structure changes over two early successional stages (<10 years and 10–20 years old) after abandonment and old-growth. We used both statistically metric and nonmetric analyses to examine correlations of community composition during successional stages and along elevational gradients. We found that (i) significant differences existed in the structural compositions between early successional forests and old-growth forests, but did not exist within early successional forests; (ii) the phylogenetic structure shifted fr...

Research paper thumbnail of Estimation and Recognition of Motion Segmentation and Pose IMU-Based Human Motion Capture

Robot Intelligence Technology and Applications 5, 2018

Talking about motion capture systems, we will think of a system that has a lot of white markers d... more Talking about motion capture systems, we will think of a system that has a lot of white markers distributed on the suit worn on the human body, can record and simulate the motion of human or any other object in the software. However, these systems are worth a lot of money, can only operate in a wide and fixed space with many cameras attached around. Therefore, only large animation filmmakers or graphic designers are capable of purchasing this type of system. In this paper, the wireless IMU-based motion capture system is researched and developed with low cost, moderate accuracy, high speed, portable as well as easy-to-use, that is our main contribution. The full-featured hardware, the very simple operation program, and controlling software are focused and built on using the low cost components. The designed system is based on a network of small inertial measurement units (IMU) called “node” distributed on the human body. In essence, the MCU is the core of the board. It collects measured data from the sensors, perform orientation filter based on a quaternion-based Madgwick orientation filter and transfer data to host via Wi-Fi or store it in the memory for later use. After that, the node’s processed data was simulated by the program called “SHURIKEN launcher”. The nodes’ behavior also is controlled by this program. All of these activities are incorporated into the operation of the system in this project. The result of experiments on accuracy demonstrated the feasibility and advantages also a few shortcomings of the system. The advantages and limitations of the system, hardware and software architecture in more detail will be discussed.

Research paper thumbnail of Assessment of sedimentation in Tri An reservoir by nuclear technique, geological analyses and GIS

VIETNAM JOURNAL OF EARTH SCIENCES, 2014

Research paper thumbnail of Present Day Deformation in the East Vietnam Sea and Surrounding Regions

Tạp chí Khoa học và Công nghệ Biển, 2015

This paper presents velocities of present-day tectonic movement and strain rate in the East Vietn... more This paper presents velocities of present-day tectonic movement and strain rate in the East Vietnam Sea (South China Sea) and surroundings determined from GPS campaigns between 2007 and 2010. We determine absolute velocities of GPS stations in the ITRF05 frame. The result indicates that GPS stations in the North of East Vietnam Sea move eastwards with the slip

Research paper thumbnail of SSTBC: Sleep scheduled and tree-based clustering routing protocol for energy-efficient in wireless sensor networks

The 2015 IEEE RIVF International Conference on Computing & Communication Technologies - Research, Innovation, and Vision for Future (RIVF), 2015

Since sensor nodes are battery power constrained devices in wireless sensor network (WSN), so how... more Since sensor nodes are battery power constrained devices in wireless sensor network (WSN), so how to use the energy of sensor nodes efficiently to prolong the network lifetime is a chief challenge for designing routing protocols. To solve this problem, in this paper, we propose sleep scheduled and tree-based clustering approach routing algorithm (SSTBC) for energy-efficient in WSN. SSTBC preserves energy by turning off radio (entering sleep mode) of either impossible or unnecessary nodes, which observe almost the same information, base on their location information to remove redundant data. In addition, to further reduce energy dissipation of communication in network, we build minimum spanning tree with the root as the cluster head (CH) from active nodes in a cluster to forward data packets to base station (BS). Our simulation results show that the network lifetime with using of our proposed protocol can be improved about 250% and 23% compared to low-energy adaptive clustering hierarchy (LEACH) and power-efficient gathering in sensor information system (PEGASIS), respectively.

Research paper thumbnail of Synthesis of well-defined poly(vinyl ether)-based macromonomers having pendant glycerols via living cationic polymerization and their application to the preparation of core−shell polymer particles

Polymer International, 2013

A new vinyl ether monomer bearing a glycerol pendant moiety protected with an isopropylidene grou... more A new vinyl ether monomer bearing a glycerol pendant moiety protected with an isopropylidene group (2-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-ethyl vinyl ether, IpGEVE) was designed as the precursor of a novel type of hydrophilic poly(vinyl ether) containing glycerol pendants. It was found that the polymerization of IpGEVE proceeded in a controlled manner, and the protecting groups of isopropylidene moieties could be cleaved with trifluoroacetic acid. Living cationic polymerization of IpGEVE with an initiator bearing a methacryloyl group (VEM-HCl) and subsequent deprotection of the pendant isopropylidene groups of the resultant precursor afforded a glycerol-substituted hydrophilic macromonomer MA-PGEVE. Nearly monodispersed polymer particles in the submicron size range were successfully obtained via dispersion copolymerization of MA-PGEVE with styrene.© 2013 Society of Chemical Industry

Research paper thumbnail of Potassium adsorption on β-FeSi2 thin films

Surface Science Letters, 1991

Potassium adsorption on thin fl-FeSi 2 epitaxiaUy grown on Si(111) was studied with ultraviolet p... more Potassium adsorption on thin fl-FeSi 2 epitaxiaUy grown on Si(111) was studied with ultraviolet photoemission spectroscopy (UPS), Auger electron spectroscopy (AES) and work function (WF) measurements. A value of (4.65 + 0.03) eV was measured for the absolute WF of the silicide surface. A combination of the experimental results upon K deposition indicates a plausible mode of K adsorption on fl-FeSi 2. Initially K adsorbs on Si triangular sites with a Fe atom underneath up to a coverage of-2 x 1014 atoms cm-2 and then on Si triangular sites with no Fe underneath up to a saturation coverage of-2 x 1014 atoms cm-2.

Research paper thumbnail of Quasi-equilibrium Inclusion Problems of the Blum–Oettli-Type and Related Problems

Springer Optimization and Its Applications, 2010

The quasi-equilibrium inclusion problems of Blum–Oettli type are formulated and sufficient condit... more The quasi-equilibrium inclusion problems of Blum–Oettli type are formulated and sufficient conditions on the existence of solutions are shown. As special cases, we obtain several results on the existence of solutions of general vector ideal (resp. proper, Pareto, weak) ...

Research paper thumbnail of A survey: energy exhausting attacks in MAC protocols in WBANs

Telecommunication Systems, 2014

Because the sensors of wireless body area networks (WBANs) have limited battery power, many studi... more Because the sensors of wireless body area networks (WBANs) have limited battery power, many studies have focused on energy efficient medium access control (MAC) protocols to extend the lifetime of the sensors. In addition, WBANs face energy-exhausting attacks, which force the sensors to consume battery power partially or thoroughly. These attacks occur mainly in the MAC layer and threaten severely the energy efficiency of MAC protocols in WBANs. Because the attacks are made abruptly and unexpectedly, the lives of human beings and the quality of health care services can be threatened. Therefore, the aim of this study was to identify the major types of energy exhausting attacks in MAC protocols in WBANs, and show how easily the attacks can cause energy exhaustion in different MAC

Research paper thumbnail of DFTBC: Data Fusion and Tree-Based Clustering Routing Protocol for Energy-Efficient in Wireless Sensor Networks

Advances in Intelligent Systems and Computing, 2015

Energy efficiency is a unique challenge for designing routing protocols in wireless sensor networ... more Energy efficiency is a unique challenge for designing routing protocols in wireless sensor network (WSN) to extend the lifetime of the entire network because sensor nodes are power constrained devices. To solve this problem, in this paper, we propose a data fusion and tree-based clustering routing algorithm (DFTBC). DFTBC designing consists of two main works. In the first work, tree-based clustering routing technique is used to connect the nodes in a cluster to form a minimum spanning tree, where each node communicates only with its nearest neighbor using distance and remaining energy of nodes to decide which node will be the cluster head (CH). In the second work, we fuse one or more packets to generate a packet with a smaller size based on the Dempster-Shafer and Slepian-Wolf theory. Our simulation results show that the network lifetime with using of our proposed protocol can be improved about 350% and 35% compared to low-energy adaptive clustering hierarchy (LEACH) and power-efficient gathering in sensor information system (PEGASIS), respectively.

Research paper thumbnail of On the primary and secondary bifurcation of equations involving scalar nonlinearities

Numerical Functional Analysis and Optimization, 1992

ABSTRACT

Research paper thumbnail of Quasi-Variational Inequalities in Topological Linear Locally Convex Hausdorff Spaces

Mathematische Nachrichten, 1985

This paper will present some results on quasivariational inequality {C, E , P , 'p} in topologica... more This paper will present some results on quasivariational inequality {C, E , P , 'p} in topological linear locally convex Hausdorff spaces. We shall be concerning with quasivariatioiial inequalities defined on subsets which are convexe closed, or only closed. The compactness of the subset C is replaced by the condensing property of the mapping E. Further, we also obtain some results for quasivariational inequality {C, E , P , v}, where the multivalued mapping E maps CI into Zx and satkfiev n general inwnrd boundary condition.

Research paper thumbnail of Measurable Solutions of Mathematical Programming Problems with a Measurable Parameter

Mathematische Nachrichten, 1986

Consider the problem with a measurable parameter t Eq of minimizing f (t, 2) subject to the follo... more Consider the problem with a measurable parameter t Eq of minimizing f (t, 2) subject to the following equality and inequality constraints:(1) gi (t, x)= 0, i= 1,..., r hj (t, z) jO, j= l,..., S, ZER&quot;,&#x27;where R&quot; is an Euomean n-dimensional space,(Q, A, p) a measurable space, and f, ...

Research paper thumbnail of Banach-Steinhaus Principle for Convex Multivalued Mappings

Mathematische Nachrichten, 1986

This paper will present some relations between the lower semi-equicontinuity of some family of mu... more This paper will present some relations between the lower semi-equicontinuity of some family of multivalued mappings from a normed apace into another one and their norms. Further, the BANA~E-STEINEAUS Principle of the uniform boundedness will be proved for the family of convex multivalued mappings. This result yields some applications on stability of solutions of nonlinear multivalued equations.

Research paper thumbnail of An Analytical Approach to Bifurcation Problems with Applications to Partial Differential Equations

Mathematische Nachrichten, 1987

Research paper thumbnail of Bifurcation from Characteristic Values for Equations Involving Fredholm Mappings with Applications to Partial Differential Equations, I. Theory

Mathematische Nachrichten, 1988

Bifurcation from Characteristic Values for Equations Involving FREDHOLM Nappings with Application... more Bifurcation from Characteristic Values for Equations Involving FREDHOLM Nappings with Applications to Partial Differential Equations, I. Theory ... The 1)urpose of this paper is to study the bifurcation problem of the equations of the form (1) where /I is an open subset of some normed ...

Research paper thumbnail of A Combination Method for Local Bifurcation from Characteristic Values with Multiplicity

Mathematische Nachrichten, 1991

Abstract A combination of the LIAPUNOV-SCHMIDT procedure, the implicit function theorems and the ... more Abstract A combination of the LIAPUNOV-SCHMIDT procedure, the implicit function theorems and the topological degree theory is used to investigate bifurcation points of equations of the form T (v)= L (λ, v)+ M (λ, v),(λ, v) ϵ A× D̄, where A is an open subset in ...

Research paper thumbnail of On the Existence of Solutions of Quasi-equilibrium Problems with Constraints

Mathematical Methods of Operations Research, 2006

The quasi-equilibrium problems with constraints are formulated and some sufficient conditions on ... more The quasi-equilibrium problems with constraints are formulated and some sufficient conditions on the existence of their solutions are shown. As special cases, we obtain several results on the existence of solutions of different vector quasivariational inequality and vector optimization problems. An application of the obtained results is given to show the existence of solutions of quasi-optimization problems with constraints.

Research paper thumbnail of On the existence of solutions to systems of vector quasi-optimization problems

Mathematical Methods of Operational Research, 2004

Some sufficient conditions for the existence of solutions to systems of vector quasi-optimization... more Some sufficient conditions for the existence of solutions to systems of vector quasi-optimization problems are given. These systems also include the systems of quasi-variational inequalities, quasi-equilibrium problems etc. As special case, we obtain some extensions for minimax theorems, general vector optimization problems, general vector quasi-optimization problems, quasiequilibrium problems... concerning vector functions. From these we generalize some well-known results obtained by Blum and Oettli [4], Park [19], Chan and Pang[6], Parida and Sen [18], Browder and Minty [16], Ky Fan [8], etc.

Research paper thumbnail of Building a Chatbot System to Analyze Opinions of English Comments

Informatics and Automation

Chatbot research has advanced significantly over the years. Enterprises have been investigating h... more Chatbot research has advanced significantly over the years. Enterprises have been investigating how to improve these tools’ performance, adoption, and implementation to communicate with customers or internal teams through social media. Besides, businesses also want to pay attention to quality reviews from customers via social networks about products available in the market. From there, please select a new method to improve the service quality of their products and then send it to publishing agencies to publish based on the needs and evaluation of society. Although there have been numerous recent studies, not all of them address the issue of opinion evaluation on the chatbot system. The primary goal of this paper’s research is to evaluate human comments in English via the chatbot system. The system’s documents are preprocessed and opinion-matched to provide opinion judgments based on English comments. Based on practical needs and social conditions, this methodology aims to evolve cha...

Research paper thumbnail of Changes in Community Composition of Tropical Evergreen Forests during Succession in Ta Dung National Park, Central Highlands of Vietnam

Forests, 2020

Degradation of tropical forests is a major driver of the global extinction crisis. A key question... more Degradation of tropical forests is a major driver of the global extinction crisis. A key question is understanding the role of evolution history during forest succession in the context of forest restoration for maintaining ecosystem function and stability. This study was conducted in a fragmented forest landscape in the central highlands of Vietnam. We sampled living trees with diameters at breast height of ≥6.0 cm in nineteen 0.25 ha plots to evaluate forest community structure changes over two early successional stages (<10 years and 10–20 years old) after abandonment and old-growth. We used both statistically metric and nonmetric analyses to examine correlations of community composition during successional stages and along elevational gradients. We found that (i) significant differences existed in the structural compositions between early successional forests and old-growth forests, but did not exist within early successional forests; (ii) the phylogenetic structure shifted fr...

Research paper thumbnail of Estimation and Recognition of Motion Segmentation and Pose IMU-Based Human Motion Capture

Robot Intelligence Technology and Applications 5, 2018

Talking about motion capture systems, we will think of a system that has a lot of white markers d... more Talking about motion capture systems, we will think of a system that has a lot of white markers distributed on the suit worn on the human body, can record and simulate the motion of human or any other object in the software. However, these systems are worth a lot of money, can only operate in a wide and fixed space with many cameras attached around. Therefore, only large animation filmmakers or graphic designers are capable of purchasing this type of system. In this paper, the wireless IMU-based motion capture system is researched and developed with low cost, moderate accuracy, high speed, portable as well as easy-to-use, that is our main contribution. The full-featured hardware, the very simple operation program, and controlling software are focused and built on using the low cost components. The designed system is based on a network of small inertial measurement units (IMU) called “node” distributed on the human body. In essence, the MCU is the core of the board. It collects measured data from the sensors, perform orientation filter based on a quaternion-based Madgwick orientation filter and transfer data to host via Wi-Fi or store it in the memory for later use. After that, the node’s processed data was simulated by the program called “SHURIKEN launcher”. The nodes’ behavior also is controlled by this program. All of these activities are incorporated into the operation of the system in this project. The result of experiments on accuracy demonstrated the feasibility and advantages also a few shortcomings of the system. The advantages and limitations of the system, hardware and software architecture in more detail will be discussed.

Research paper thumbnail of Assessment of sedimentation in Tri An reservoir by nuclear technique, geological analyses and GIS

VIETNAM JOURNAL OF EARTH SCIENCES, 2014

Research paper thumbnail of Present Day Deformation in the East Vietnam Sea and Surrounding Regions

Tạp chí Khoa học và Công nghệ Biển, 2015

This paper presents velocities of present-day tectonic movement and strain rate in the East Vietn... more This paper presents velocities of present-day tectonic movement and strain rate in the East Vietnam Sea (South China Sea) and surroundings determined from GPS campaigns between 2007 and 2010. We determine absolute velocities of GPS stations in the ITRF05 frame. The result indicates that GPS stations in the North of East Vietnam Sea move eastwards with the slip

Research paper thumbnail of SSTBC: Sleep scheduled and tree-based clustering routing protocol for energy-efficient in wireless sensor networks

The 2015 IEEE RIVF International Conference on Computing & Communication Technologies - Research, Innovation, and Vision for Future (RIVF), 2015

Since sensor nodes are battery power constrained devices in wireless sensor network (WSN), so how... more Since sensor nodes are battery power constrained devices in wireless sensor network (WSN), so how to use the energy of sensor nodes efficiently to prolong the network lifetime is a chief challenge for designing routing protocols. To solve this problem, in this paper, we propose sleep scheduled and tree-based clustering approach routing algorithm (SSTBC) for energy-efficient in WSN. SSTBC preserves energy by turning off radio (entering sleep mode) of either impossible or unnecessary nodes, which observe almost the same information, base on their location information to remove redundant data. In addition, to further reduce energy dissipation of communication in network, we build minimum spanning tree with the root as the cluster head (CH) from active nodes in a cluster to forward data packets to base station (BS). Our simulation results show that the network lifetime with using of our proposed protocol can be improved about 250% and 23% compared to low-energy adaptive clustering hierarchy (LEACH) and power-efficient gathering in sensor information system (PEGASIS), respectively.

Research paper thumbnail of Synthesis of well-defined poly(vinyl ether)-based macromonomers having pendant glycerols via living cationic polymerization and their application to the preparation of core−shell polymer particles

Polymer International, 2013

A new vinyl ether monomer bearing a glycerol pendant moiety protected with an isopropylidene grou... more A new vinyl ether monomer bearing a glycerol pendant moiety protected with an isopropylidene group (2-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-ethyl vinyl ether, IpGEVE) was designed as the precursor of a novel type of hydrophilic poly(vinyl ether) containing glycerol pendants. It was found that the polymerization of IpGEVE proceeded in a controlled manner, and the protecting groups of isopropylidene moieties could be cleaved with trifluoroacetic acid. Living cationic polymerization of IpGEVE with an initiator bearing a methacryloyl group (VEM-HCl) and subsequent deprotection of the pendant isopropylidene groups of the resultant precursor afforded a glycerol-substituted hydrophilic macromonomer MA-PGEVE. Nearly monodispersed polymer particles in the submicron size range were successfully obtained via dispersion copolymerization of MA-PGEVE with styrene.© 2013 Society of Chemical Industry

Research paper thumbnail of Potassium adsorption on β-FeSi2 thin films

Surface Science Letters, 1991

Potassium adsorption on thin fl-FeSi 2 epitaxiaUy grown on Si(111) was studied with ultraviolet p... more Potassium adsorption on thin fl-FeSi 2 epitaxiaUy grown on Si(111) was studied with ultraviolet photoemission spectroscopy (UPS), Auger electron spectroscopy (AES) and work function (WF) measurements. A value of (4.65 + 0.03) eV was measured for the absolute WF of the silicide surface. A combination of the experimental results upon K deposition indicates a plausible mode of K adsorption on fl-FeSi 2. Initially K adsorbs on Si triangular sites with a Fe atom underneath up to a coverage of-2 x 1014 atoms cm-2 and then on Si triangular sites with no Fe underneath up to a saturation coverage of-2 x 1014 atoms cm-2.

Research paper thumbnail of Quasi-equilibrium Inclusion Problems of the Blum–Oettli-Type and Related Problems

Springer Optimization and Its Applications, 2010

The quasi-equilibrium inclusion problems of Blum–Oettli type are formulated and sufficient condit... more The quasi-equilibrium inclusion problems of Blum–Oettli type are formulated and sufficient conditions on the existence of solutions are shown. As special cases, we obtain several results on the existence of solutions of general vector ideal (resp. proper, Pareto, weak) ...

Research paper thumbnail of A survey: energy exhausting attacks in MAC protocols in WBANs

Telecommunication Systems, 2014

Because the sensors of wireless body area networks (WBANs) have limited battery power, many studi... more Because the sensors of wireless body area networks (WBANs) have limited battery power, many studies have focused on energy efficient medium access control (MAC) protocols to extend the lifetime of the sensors. In addition, WBANs face energy-exhausting attacks, which force the sensors to consume battery power partially or thoroughly. These attacks occur mainly in the MAC layer and threaten severely the energy efficiency of MAC protocols in WBANs. Because the attacks are made abruptly and unexpectedly, the lives of human beings and the quality of health care services can be threatened. Therefore, the aim of this study was to identify the major types of energy exhausting attacks in MAC protocols in WBANs, and show how easily the attacks can cause energy exhaustion in different MAC

Research paper thumbnail of DFTBC: Data Fusion and Tree-Based Clustering Routing Protocol for Energy-Efficient in Wireless Sensor Networks

Advances in Intelligent Systems and Computing, 2015

Energy efficiency is a unique challenge for designing routing protocols in wireless sensor networ... more Energy efficiency is a unique challenge for designing routing protocols in wireless sensor network (WSN) to extend the lifetime of the entire network because sensor nodes are power constrained devices. To solve this problem, in this paper, we propose a data fusion and tree-based clustering routing algorithm (DFTBC). DFTBC designing consists of two main works. In the first work, tree-based clustering routing technique is used to connect the nodes in a cluster to form a minimum spanning tree, where each node communicates only with its nearest neighbor using distance and remaining energy of nodes to decide which node will be the cluster head (CH). In the second work, we fuse one or more packets to generate a packet with a smaller size based on the Dempster-Shafer and Slepian-Wolf theory. Our simulation results show that the network lifetime with using of our proposed protocol can be improved about 350% and 35% compared to low-energy adaptive clustering hierarchy (LEACH) and power-efficient gathering in sensor information system (PEGASIS), respectively.

Research paper thumbnail of On the primary and secondary bifurcation of equations involving scalar nonlinearities

Numerical Functional Analysis and Optimization, 1992

ABSTRACT

Research paper thumbnail of Quasi-Variational Inequalities in Topological Linear Locally Convex Hausdorff Spaces

Mathematische Nachrichten, 1985

This paper will present some results on quasivariational inequality {C, E , P , 'p} in topologica... more This paper will present some results on quasivariational inequality {C, E , P , 'p} in topological linear locally convex Hausdorff spaces. We shall be concerning with quasivariatioiial inequalities defined on subsets which are convexe closed, or only closed. The compactness of the subset C is replaced by the condensing property of the mapping E. Further, we also obtain some results for quasivariational inequality {C, E , P , v}, where the multivalued mapping E maps CI into Zx and satkfiev n general inwnrd boundary condition.

Research paper thumbnail of Measurable Solutions of Mathematical Programming Problems with a Measurable Parameter

Mathematische Nachrichten, 1986

Consider the problem with a measurable parameter t Eq of minimizing f (t, 2) subject to the follo... more Consider the problem with a measurable parameter t Eq of minimizing f (t, 2) subject to the following equality and inequality constraints:(1) gi (t, x)= 0, i= 1,..., r hj (t, z) jO, j= l,..., S, ZER&quot;,&#x27;where R&quot; is an Euomean n-dimensional space,(Q, A, p) a measurable space, and f, ...

Research paper thumbnail of Banach-Steinhaus Principle for Convex Multivalued Mappings

Mathematische Nachrichten, 1986

This paper will present some relations between the lower semi-equicontinuity of some family of mu... more This paper will present some relations between the lower semi-equicontinuity of some family of multivalued mappings from a normed apace into another one and their norms. Further, the BANA~E-STEINEAUS Principle of the uniform boundedness will be proved for the family of convex multivalued mappings. This result yields some applications on stability of solutions of nonlinear multivalued equations.

Research paper thumbnail of An Analytical Approach to Bifurcation Problems with Applications to Partial Differential Equations

Mathematische Nachrichten, 1987

Research paper thumbnail of Bifurcation from Characteristic Values for Equations Involving Fredholm Mappings with Applications to Partial Differential Equations, I. Theory

Mathematische Nachrichten, 1988

Bifurcation from Characteristic Values for Equations Involving FREDHOLM Nappings with Application... more Bifurcation from Characteristic Values for Equations Involving FREDHOLM Nappings with Applications to Partial Differential Equations, I. Theory ... The 1)urpose of this paper is to study the bifurcation problem of the equations of the form (1) where /I is an open subset of some normed ...

Research paper thumbnail of A Combination Method for Local Bifurcation from Characteristic Values with Multiplicity

Mathematische Nachrichten, 1991

Abstract A combination of the LIAPUNOV-SCHMIDT procedure, the implicit function theorems and the ... more Abstract A combination of the LIAPUNOV-SCHMIDT procedure, the implicit function theorems and the topological degree theory is used to investigate bifurcation points of equations of the form T (v)= L (λ, v)+ M (λ, v),(λ, v) ϵ A× D̄, where A is an open subset in ...

Research paper thumbnail of On the Existence of Solutions of Quasi-equilibrium Problems with Constraints

Mathematical Methods of Operations Research, 2006

The quasi-equilibrium problems with constraints are formulated and some sufficient conditions on ... more The quasi-equilibrium problems with constraints are formulated and some sufficient conditions on the existence of their solutions are shown. As special cases, we obtain several results on the existence of solutions of different vector quasivariational inequality and vector optimization problems. An application of the obtained results is given to show the existence of solutions of quasi-optimization problems with constraints.

Research paper thumbnail of On the existence of solutions to systems of vector quasi-optimization problems

Mathematical Methods of Operational Research, 2004

Some sufficient conditions for the existence of solutions to systems of vector quasi-optimization... more Some sufficient conditions for the existence of solutions to systems of vector quasi-optimization problems are given. These systems also include the systems of quasi-variational inequalities, quasi-equilibrium problems etc. As special case, we obtain some extensions for minimax theorems, general vector optimization problems, general vector quasi-optimization problems, quasiequilibrium problems... concerning vector functions. From these we generalize some well-known results obtained by Blum and Oettli [4], Park [19], Chan and Pang[6], Parida and Sen [18], Browder and Minty [16], Ky Fan [8], etc.