Pub Date : 2020-12-29DOI: 10.31130/ICT-UD.2020.111
T. Nguyen
We give a short survey about evaluation of initial degree and Waldschmidt constant of zero schemes in projective space. We show main and updated results, some related conjectures and new computations of initial degree and Waldschmidt constant
{"title":"Initial degree and Waldschmidt constant of zero schemes and properties","authors":"T. Nguyen","doi":"10.31130/ICT-UD.2020.111","DOIUrl":"https://doi.org/10.31130/ICT-UD.2020.111","url":null,"abstract":"We give a short survey about evaluation of initial degree and Waldschmidt constant of zero schemes in projective space. We show main and updated results, some related conjectures and new computations of initial degree and Waldschmidt constant","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"107 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132772812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-29DOI: 10.31130/ICT-UD.2020.109
Thu A. Pham, N. Dang
This paper aims at proposing a novel satellite quantum key distribution (QKD) system for vehicular networks. Quantum key from a satellite (i.e., a trusted node) is transmitted through a free-space optical (FSO) channel to a high-attitude platform (HAP) using radio-over-FSO (RoFSO) technique. HAP playing a role as a relaying node forwards the key to moving vehicles via millimeter-wave (MMW) channel. Key information generated is encoded on MMW subcarrier using binary phase shift keying (BPSK) signaling and then recovered at the receiver thanks to a dual-threshold detector. We derive the mathematical expressions for security analysis of the proposed QKD system in terms of quantum bit error rate and ergodic secret-key rate taking into account the channel loss and receiver noise. The numerical results confirm the feasibility of the proposed QKD system.
{"title":"Relay-Assisted Satellite QKD Systems using MMW Radio-over-FSO for Vehicular Networks","authors":"Thu A. Pham, N. Dang","doi":"10.31130/ICT-UD.2020.109","DOIUrl":"https://doi.org/10.31130/ICT-UD.2020.109","url":null,"abstract":"This paper aims at proposing a novel satellite quantum key distribution (QKD) system for vehicular networks. Quantum key from a satellite (i.e., a trusted node) is transmitted through a free-space optical (FSO) channel to a high-attitude platform (HAP) using radio-over-FSO (RoFSO) technique. HAP playing a role as a relaying node forwards the key to moving vehicles via millimeter-wave (MMW) channel. Key information generated is encoded on MMW subcarrier using binary phase shift keying (BPSK) signaling and then recovered at the receiver thanks to a dual-threshold detector. We derive the mathematical expressions for security analysis of the proposed QKD system in terms of quantum bit error rate and ergodic secret-key rate taking into account the channel loss and receiver noise. The numerical results confirm the feasibility of the proposed QKD system.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121966208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-29DOI: 10.31130/ICT-UD.2020.104
P. Nguyen, Q. Duong, Minh Van Luong, Hoang Duc Chu
With the strong development of science and technology, the study of technologies related to environmental forecasting is important. In recent years, the application of smart technology in aquaculture has been widely applied. Based on the requirement, we focus on predicting the environmental parameters applied in shrimp farming, especially white shrimp, one of the seafood grown in our country. In the paper, we exploit a small branch of identification problem. This paper proposes an algorithmic construction method to predict changes in shrimp farm environmental parameters and simulate the next parameters based on current parameters. The goal of the paper is to reduce the parameter of Recurrent Neural Network (RNN) while ensuring data accuracy. Experimental results show that the proposal algorithm improves up to 85 percent when selecting suitable learning factor of neural networks.
{"title":"Designing Forecasting Parameter Algorithm of Environmental Shrimp Using Recurrent Neural Network","authors":"P. Nguyen, Q. Duong, Minh Van Luong, Hoang Duc Chu","doi":"10.31130/ICT-UD.2020.104","DOIUrl":"https://doi.org/10.31130/ICT-UD.2020.104","url":null,"abstract":"With the strong development of science and technology, the study of technologies related to environmental forecasting is important. In recent years, the application of smart technology in aquaculture has been widely applied. Based on the requirement, we focus on predicting the environmental parameters applied in shrimp farming, especially white shrimp, one of the seafood grown in our country. In the paper, we exploit a small branch of identification problem. This paper proposes an algorithmic construction method to predict changes in shrimp farm environmental parameters and simulate the next parameters based on current parameters. The goal of the paper is to reduce the parameter of Recurrent Neural Network (RNN) while ensuring data accuracy. Experimental results show that the proposal algorithm improves up to 85 percent when selecting suitable learning factor of neural networks.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"40 14","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113939276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper studies the problems of precoding designs to achieve the energy efficiency (EE) in the uplink heterogeneous networks in which the multiple small cells are deployed in a macro-cell. We consider two design problems which maximize either the total system energy efficiency (SEE) or the minimum energy efficiency (MinEE) among users subject to the transmit power constraints at each user and interference constraints caused to the macro base station. Since the optimization problems are non-convex fractional programming in matrix variables, it cannot be straightforward to obtain the optimal solutions. To tackle with the non-convexity challenges of the design problems, we adopt the relationships between the minimum mean square error (MMSE) and achievable data rate to recast the EE problems into ones more amenable. Then, we employ the block coordinate ascent (BCA) and the Dinkelbach methods to develop efficient iterative algorithms in which the closed form solutions are obtained or the semi-definite programming (SDP) problems are solved at each iteration. Simulation results are provided to investigate the EE performance of the EE optimization as compared to those of the spectral efficiency (SE) optimization.
{"title":"An Alternating Optimization Algorithm for Energy Efficiency in Heterogeneous Networks","authors":"K. H. Ha, T. Ha","doi":"10.31130/JST.2018.62","DOIUrl":"https://doi.org/10.31130/JST.2018.62","url":null,"abstract":"This paper studies the problems of precoding designs to achieve the energy efficiency (EE) in the uplink heterogeneous networks in which the multiple small cells are deployed in a macro-cell. We consider two design problems which maximize either the total system energy efficiency (SEE) or the minimum energy efficiency (MinEE) among users subject to the transmit power constraints at each user and interference constraints caused to the macro base station. Since the optimization problems are non-convex fractional programming in matrix variables, it cannot be straightforward to obtain the optimal solutions. To tackle with the non-convexity challenges of the design problems, we adopt the relationships between the minimum mean square error (MMSE) and achievable data rate to recast the EE problems into ones more amenable. Then, we employ the block coordinate ascent (BCA) and the Dinkelbach methods to develop efficient iterative algorithms in which the closed form solutions are obtained or the semi-definite programming (SDP) problems are solved at each iteration. Simulation results are provided to investigate the EE performance of the EE optimization as compared to those of the spectral efficiency (SE) optimization.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115173127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dao Duy Tu, Linh Duc Tam Ho, Dung Truong Cao, H.T. Nguyen
In this paper, an all-optical logic gate based on 2x2 (MMI) multimode interference coupler is theoretically designed and simulated using three-dimensional beam propagation method (3D-BPM) and effective index method (EIM) to analyze and evaluate the performance of the device. The proposed device is used to convert phase information of input optical signals to amplitude at the output ports of MMI. With this mechanism, the device can operates as a logical half adder. Simulation results show that the optical half adder archives with insertion loss and extinction ratio from ON to OFF logic–level below 0.7 dB and over 40 dB, respectively. Furthermore, wide bandwidth of 100nm is also an advantage of this devices. Therefore, it can be applied to all optical signal processing in next generation optical networks as well as in photonics integrated circuits.
{"title":"All-Optical Half Adder Based on a 2x2 Multimode Interference Coupler","authors":"Dao Duy Tu, Linh Duc Tam Ho, Dung Truong Cao, H.T. Nguyen","doi":"10.31130/JST.2018.71","DOIUrl":"https://doi.org/10.31130/JST.2018.71","url":null,"abstract":"In this paper, an all-optical logic gate based on 2x2 (MMI) multimode interference coupler is theoretically designed and simulated using three-dimensional beam propagation method (3D-BPM) and effective index method (EIM) to analyze and evaluate the performance of the device. The proposed device is used to convert phase information of input optical signals to amplitude at the output ports of MMI. With this mechanism, the device can operates as a logical half adder. Simulation results show that the optical half adder archives with insertion loss and extinction ratio from ON to OFF logic–level below 0.7 dB and over 40 dB, respectively. Furthermore, wide bandwidth of 100nm is also an advantage of this devices. Therefore, it can be applied to all optical signal processing in next generation optical networks as well as in photonics integrated circuits.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"7 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124905633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we propose a novel home area networks (HAN) architecture using MMW radio-over-plastic optical fiber (MMW/RoPOF) to provide high-speed wireless connections to end users. The proposed HAN can support bidirectional half-duplex communication between any pair of mobile stations (MSs) thanks to the use of analog network coding in optical domain implemented at a center station (CS). We analyze the performance of an end-to-end communication link between two MSs under the impact of major physical impairments originated from both fiber and wireless links. The numerical results in terms of bit error rate (BER) and normalized throughput demonstrate that it is feasible to deploy MMW/RoPOF in HAN. In addition, useful information for the design of HAN can be obtained from this paper.
{"title":"Bidirectional Relaying MMW Radio over Plastic Optical Fiber Systems in Home Area Networks","authors":"Thu A. Pham, Lam T. Vu, N. Dang","doi":"10.31130/jst.2018.63","DOIUrl":"https://doi.org/10.31130/jst.2018.63","url":null,"abstract":"In this paper, we propose a novel home area networks (HAN) architecture using MMW radio-over-plastic optical fiber (MMW/RoPOF) to provide high-speed wireless connections to end users. The proposed HAN can support bidirectional half-duplex communication between any pair of mobile stations (MSs) thanks to the use of analog network coding in optical domain implemented at a center station (CS). We analyze the performance of an end-to-end communication link between two MSs under the impact of major physical impairments originated from both fiber and wireless links. The numerical results in terms of bit error rate (BER) and normalized throughput demonstrate that it is feasible to deploy MMW/RoPOF in HAN. In addition, useful information for the design of HAN can be obtained from this paper.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128655945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ngoc Pham Thi Dan, Duy Tran Trung, Khuong Ho‐Van, N. T. Binh
This paper evaluates outage probability (OP) of a path-selection protocol in multi-path multi-hop decode-and-forward (DF) relaying networks. In the considered protocol, relying on the end-to-end signal to interference-plus-noise ratio (SINR), the best path between the source and the destination is selected to enhance the outage performance under joint impact of co-channel interference and hardware imperfection. We derive exact and asymptotic closed-form expressions of the end-to-end OP for the considered protocol over Rayleigh fading channels. The simulation results are then presented to validate the theoretical results.
{"title":"Performance Evaluation of Best Path Selection Protocol in Multi-hop Relaying Networks under Joint Impact of Co-channel Interference and Hardware Impairments","authors":"Ngoc Pham Thi Dan, Duy Tran Trung, Khuong Ho‐Van, N. T. Binh","doi":"10.31130/JST.2018.66","DOIUrl":"https://doi.org/10.31130/JST.2018.66","url":null,"abstract":"This paper evaluates outage probability (OP) of a path-selection protocol in multi-path multi-hop decode-and-forward (DF) relaying networks. In the considered protocol, relying on the end-to-end signal to interference-plus-noise ratio (SINR), the best path between the source and the destination is selected to enhance the outage performance under joint impact of co-channel interference and hardware imperfection. We derive exact and asymptotic closed-form expressions of the end-to-end OP for the considered protocol over Rayleigh fading channels. The simulation results are then presented to validate the theoretical results.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114231749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Up to now, smart lighting solutions have been researched and deployed in many cities around the world. This application has saved much energy due to the capability of optimizing the lighting control mechanism. In this paper, a framework used for smart lighting system is proposed under the consideration of many issues such as hardware devices, routing protocol, security, and scalability in layers. The performance evaluation is also investigated in several simulated scenarios and test-beds to show the advantages of the proposed framework.
{"title":"A Networking Framework for Smart Street Lighting System using 6LoWPAN/IPv6","authors":"V. Son, L. M. Phương","doi":"10.31130/jst.2018.65","DOIUrl":"https://doi.org/10.31130/jst.2018.65","url":null,"abstract":"Up to now, smart lighting solutions have been researched and deployed in many cities around the world. This application has saved much energy due to the capability of optimizing the lighting control mechanism. In this paper, a framework used for smart lighting system is proposed under the consideration of many issues such as hardware devices, routing protocol, security, and scalability in layers. The performance evaluation is also investigated in several simulated scenarios and test-beds to show the advantages of the proposed framework.","PeriodicalId":114451,"journal":{"name":"Journal of Science and Technology: Issue on Information and Communications Technology","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130356911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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