A homologous series of benzothiazole derivatives, 6-methoxy-2-（4-alkanoyloxybenzylidenamino）benzothiazoles, were synthesized and characterized using FT-IR, ^1H and ^13C NMR, mass spectrometry and elemental analysis....A homologous series of benzothiazole derivatives, 6-methoxy-2-（4-alkanoyloxybenzylidenamino）benzothiazoles, were synthesized and characterized using FT-IR, ^1H and ^13C NMR, mass spectrometry and elemental analysis. Enantiotropic nematic phase was observed throughout the entire series. Smectic C phase only emerged from the decanoyloxy derivative onwards. The terminal methoxyl group and the ester linkage influenced the mesomorphic behavior of the present series.展开更多
A homologous series of Schiff base esters,4-chlorobenzylidene-4'-n-alkanoyloxyanilines,containing even number of carbons at the end groups of the molecules(C_(n-1)H_(2n-1)COO-,n=4,6,8,10,12,14,16) were synthesized...A homologous series of Schiff base esters,4-chlorobenzylidene-4'-n-alkanoyloxyanilines,containing even number of carbons at the end groups of the molecules(C_(n-1)H_(2n-1)COO-,n=4,6,8,10,12,14,16) were synthesized.The mesomorphic properties were investigated by differential scanning calorimetry(DSC) and polarizing optical microscopy(POM).It was found that the end groups of the molecules had an effect on the mesomorphic properties.n-Butanoyloxy was found non-mesogenic,whilst n-hexanoyloxy exhibited monotropic smectic phase.The higher members in this homologous series were enantiotropic smectogens.展开更多
The growing interest in Honeypots has resulted in increased research, and consequently, a large number of research surveys and/or reviews. Most Honeypot surveys and/or reviews focus on specific and narrow Honeypot res...The growing interest in Honeypots has resulted in increased research, and consequently, a large number of research surveys and/or reviews. Most Honeypot surveys and/or reviews focus on specific and narrow Honeypot research areas. This study aims at exploring and presenting advances and trends in Honeypot’s research and development areas. To this end, a systematic methodology and meta-review analysis were applied to the selection, evaluation, and qualitative examination of the most influential Honeypot surveys and/or reviews available in scientific bibliographic databases. A total of 188 papers have been evaluated and 22 research papers are found by this study to have a higher impact. The findings of the study suggest that the Honeypot survey and/or review papers of considerable relevance to the research community were mostly published in 2018, by IEEE, in conferences organized in India, and included in the IEEE Xplore database. Also, there have been few qualities Honeypot surveys and/or reviews published after 2018. Furthermore, the study identified 10 classes of vital and emerging themes and/or key topics in Honeypot research. This work contributes to research efforts employing established systematic review and reporting methods in Honeypot research. We have included our meta-review methodology, in order to allow further work in this area aiming at a better understanding of the progression of Honeypot research and advances.展开更多
A new series of Schiff base esters, 4-（dimethylamino）benzylidene-4＇-alkanoyloxyanilines containing even number of carbons at the end group of the molecules （Cn-1H2n-1COO, n = 6, 8, 10, 12, 14, 16, 18） were synthe...A new series of Schiff base esters, 4-（dimethylamino）benzylidene-4＇-alkanoyloxyanilines containing even number of carbons at the end group of the molecules （Cn-1H2n-1COO, n = 6, 8, 10, 12, 14, 16, 18） were synthesized. The present compounds were monotropic liquid crystals. It was also found that the end groups of the molecules had effect on the mesomorphic properties. C 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
The design and synthesis of new calamitic benzothiazole-based liquid crystals,2-[4-（4-alkyloxybenzoyloxy）-phenyl]ben-zothiazoles are presented.The target compound was characterized using spectroscopic techniques,suc...The design and synthesis of new calamitic benzothiazole-based liquid crystals,2-[4-（4-alkyloxybenzoyloxy）-phenyl]ben-zothiazoles are presented.The target compound was characterized using spectroscopic techniques,such as FT-IR,NMR（~1H and ^（13）C）,microanalysis and EI-MS.The liquid crystalline behaviours of these compounds were thoroughly examined by differential scanning calorimetry and polarizing optical microscope techniques.These materials exhibited enantiotropic nematic phase with high thermal stability（168℃）.Smectic A phase starts to emerge as monotropic（metastable） phase from C10 member and changes into enantiotropic（stable） phase from C12 and persists up to C16 members.展开更多
The concept of facial impact protection mask for cyclists is proposed in response to increased participation in cycling and the need for injury prevention. The research aims to develop an approach for design of facial...The concept of facial impact protection mask for cyclists is proposed in response to increased participation in cycling and the need for injury prevention. The research aims to develop an approach for design of facial impact protection gear to reduce the risk of severe injury. Impact test equipment and procedure, face surrogate and protection material performance criteria are developed. Three groups of protective materials – rigid crushable, semi rigid, and soft cushion foams are tested and assessed according to criteria. The criteria are linked to measures of the risk of facial and brain injuries: HIC (Head Injury Criterion), peak deceleration, Face-bone damage and energy absorption. The impact energy is simulated by a drop test using a 48 mm-radius-steel hemispherical impactor, with a weight of 4.63 kg similar to that of headform J specified in AS/NZS standard. The drop-height is 1500 mm, and the linear deceleration force of the impactor is recorded and used to establish the performance of the materials. The HIC is used to predict the risk of brain injury, whereas the developed face surrogate is used to assess facial bone injury. A 5.4 m/s facial impact to the unprotected-face of a cyclist can result in the risk of severe facial bone fracture and mild brain injury. The impact test results for rigid foam protection of 40 mm thickness shows no densification (bottom out) and absorbs the impact energy without damage to the Foam-bone of the face surrogate. At 20 mm thickness, rigid polyurethane foams performed best with Foam-bone damage ranging from 15.1% to 20.5%. Other materials with thicknesses of 20 to 28 mm showed Foam-bone damage between 21.8% and 35.1%. The HIC values ranged from 267 to 522, with memory foams and expanded polystyrene foam having the lowest values. Peak deceleration ranged from 71 g to 105 g for the materials tested. It is concluded that the impact energy can be dissipated by the protection material thereby reducing the risk of severe facial injury to the protected area.展开更多
Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabili...Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabilities. To effectively detect and mitigate cyberattacks, both computerized and visual analyses are typically required. However, most security analysts are not adequately trained in visualization principles and/or methods, which is required for effective visual perception of useful attack information hidden in attack data. Additionally, Honeypot has proven useful in cyberattack research, but no studies have comprehensively investigated visualization practices in the field. In this paper, we reviewed visualization practices and methods commonly used in the discovery and communication of attack patterns based on Honeypot network traffic data. Using the PRISMA methodology, we identified and screened 218 papers and evaluated only 37 papers having a high impact. Most Honeypot papers conducted summary statistics of Honeypot data based on static data metrics such as IP address, port, and packet size. They visually analyzed Honeypot attack data using simple graphical methods (such as line, bar, and pie charts) that tend to hide useful attack information. Furthermore, only a few papers conducted extended attack analysis, and commonly visualized attack data using scatter and linear plots. Papers rarely included simple yet sophisticated graphical methods, such as box plots and histograms, which allow for critical evaluation of analysis results. While a significant number of automated visualization tools have incorporated visualization standards by default, the construction of effective and expressive graphical methods for easy pattern discovery and explainable insights still requires applied knowledge and skill of visualization principles and tools, and occasionally, an interdisciplinary collaboration with peers. We, therefore, suggest the need, going forward, for non-classical graphical methods for visualizing attack patterns and communicating analysis results. We also recommend training investigators in visualization principles and standards for effective visual perception and presentation.展开更多
In this paper, the synthesis of new mesomorphic benzothiazolyl derivatives, 6-ethoxy-2-[4-（4- alkyloxybenzoyloxy）benzylidenamino]benzothiazoles, is presented. The structures of the title compounds were elucidated us...In this paper, the synthesis of new mesomorphic benzothiazolyl derivatives, 6-ethoxy-2-[4-（4- alkyloxybenzoyloxy）benzylidenamino]benzothiazoles, is presented. The structures of the title compounds were elucidated using spectroscopic techniques, such as FT-IR, NMR （1H and 13C）, elemental analysis and El-MS. The mesomorphic behaviours of these compounds were determined by differential scanning calorimetric and polarizing optical microscopic techniques. Compounds exhibited nematic and tilted smectic phases upon heating from crystal phase. An obvious odd-even effect was observed in this homologous series.展开更多
A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibite...A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibited an enantiotropic nematic phase. The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties. 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
In this paper, an innovative Genetic Algorithms (GA)-based inexact non-linear programming (GAINLP) problem solving approach has been proposed for solving non-linear programming optimization problems with inexact infor...In this paper, an innovative Genetic Algorithms (GA)-based inexact non-linear programming (GAINLP) problem solving approach has been proposed for solving non-linear programming optimization problems with inexact information (inexact non-linear operation programming). GAINLP was developed based on a GA-based inexact quadratic solving method. The Genetic Algorithm Solver of the Global Optimization Toolbox (GASGOT) developed by MATLABTM was adopted as the implementation environment of this study. GAINLP was applied to a municipality solid waste management case. The results from different scenarios indicated that the proposed GA-based heuristic optimization approach was able to generate a solution for a complicated nonlinear problem, which also involved uncertainty.展开更多
基金Universiti Tunku Abdul Rahrnan(UTAR) for the research facilities and financial support(No.6202/K06)the Malaysian Toray Science Foundation(No.4359/000) for funding this project.T.M.Koh would like to acknowledge UTAR for the award of the research and teaching assistantships.
文摘A homologous series of benzothiazole derivatives, 6-methoxy-2-（4-alkanoyloxybenzylidenamino）benzothiazoles, were synthesized and characterized using FT-IR, ^1H and ^13C NMR, mass spectrometry and elemental analysis. Enantiotropic nematic phase was observed throughout the entire series. Smectic C phase only emerged from the decanoyloxy derivative onwards. The terminal methoxyl group and the ester linkage influenced the mesomorphic behavior of the present series.
基金Universiti Tunku Abdul Rahman(UTAR) for the financial support through UTAR Vote No.6202/O05the Malaysia Toray Science Foundation(UTAR Vote No.4359/000) for funding this project
文摘A homologous series of Schiff base esters,4-chlorobenzylidene-4'-n-alkanoyloxyanilines,containing even number of carbons at the end groups of the molecules(C_(n-1)H_(2n-1)COO-,n=4,6,8,10,12,14,16) were synthesized.The mesomorphic properties were investigated by differential scanning calorimetry(DSC) and polarizing optical microscopy(POM).It was found that the end groups of the molecules had an effect on the mesomorphic properties.n-Butanoyloxy was found non-mesogenic,whilst n-hexanoyloxy exhibited monotropic smectic phase.The higher members in this homologous series were enantiotropic smectogens.
文摘The growing interest in Honeypots has resulted in increased research, and consequently, a large number of research surveys and/or reviews. Most Honeypot surveys and/or reviews focus on specific and narrow Honeypot research areas. This study aims at exploring and presenting advances and trends in Honeypot’s research and development areas. To this end, a systematic methodology and meta-review analysis were applied to the selection, evaluation, and qualitative examination of the most influential Honeypot surveys and/or reviews available in scientific bibliographic databases. A total of 188 papers have been evaluated and 22 research papers are found by this study to have a higher impact. The findings of the study suggest that the Honeypot survey and/or review papers of considerable relevance to the research community were mostly published in 2018, by IEEE, in conferences organized in India, and included in the IEEE Xplore database. Also, there have been few qualities Honeypot surveys and/or reviews published after 2018. Furthermore, the study identified 10 classes of vital and emerging themes and/or key topics in Honeypot research. This work contributes to research efforts employing established systematic review and reporting methods in Honeypot research. We have included our meta-review methodology, in order to allow further work in this area aiming at a better understanding of the progression of Honeypot research and advances.
基金Universiti Tunku Abdul Rahman(UTAR) for the research facilities andfinancial support through UTAR Vote No.6202/O05Universiti Sains Malaysia for the use of its research facilities.
文摘A new series of Schiff base esters, 4-（dimethylamino）benzylidene-4＇-alkanoyloxyanilines containing even number of carbons at the end group of the molecules （Cn-1H2n-1COO, n = 6, 8, 10, 12, 14, 16, 18） were synthesized. The present compounds were monotropic liquid crystals. It was also found that the end groups of the molecules had effect on the mesomorphic properties. C 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金Universiti Tunku Abdul Rahman(UTAR) for the UTAR Research Fund (No.6200/H02)the Malaysia Toray Science Foundation(No.4359/000) for funding this project
文摘The design and synthesis of new calamitic benzothiazole-based liquid crystals,2-[4-（4-alkyloxybenzoyloxy）-phenyl]ben-zothiazoles are presented.The target compound was characterized using spectroscopic techniques,such as FT-IR,NMR（~1H and ^（13）C）,microanalysis and EI-MS.The liquid crystalline behaviours of these compounds were thoroughly examined by differential scanning calorimetry and polarizing optical microscope techniques.These materials exhibited enantiotropic nematic phase with high thermal stability（168℃）.Smectic A phase starts to emerge as monotropic（metastable） phase from C10 member and changes into enantiotropic（stable） phase from C12 and persists up to C16 members.
文摘The concept of facial impact protection mask for cyclists is proposed in response to increased participation in cycling and the need for injury prevention. The research aims to develop an approach for design of facial impact protection gear to reduce the risk of severe injury. Impact test equipment and procedure, face surrogate and protection material performance criteria are developed. Three groups of protective materials – rigid crushable, semi rigid, and soft cushion foams are tested and assessed according to criteria. The criteria are linked to measures of the risk of facial and brain injuries: HIC (Head Injury Criterion), peak deceleration, Face-bone damage and energy absorption. The impact energy is simulated by a drop test using a 48 mm-radius-steel hemispherical impactor, with a weight of 4.63 kg similar to that of headform J specified in AS/NZS standard. The drop-height is 1500 mm, and the linear deceleration force of the impactor is recorded and used to establish the performance of the materials. The HIC is used to predict the risk of brain injury, whereas the developed face surrogate is used to assess facial bone injury. A 5.4 m/s facial impact to the unprotected-face of a cyclist can result in the risk of severe facial bone fracture and mild brain injury. The impact test results for rigid foam protection of 40 mm thickness shows no densification (bottom out) and absorbs the impact energy without damage to the Foam-bone of the face surrogate. At 20 mm thickness, rigid polyurethane foams performed best with Foam-bone damage ranging from 15.1% to 20.5%. Other materials with thicknesses of 20 to 28 mm showed Foam-bone damage between 21.8% and 35.1%. The HIC values ranged from 267 to 522, with memory foams and expanded polystyrene foam having the lowest values. Peak deceleration ranged from 71 g to 105 g for the materials tested. It is concluded that the impact energy can be dissipated by the protection material thereby reducing the risk of severe facial injury to the protected area.
文摘Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabilities. To effectively detect and mitigate cyberattacks, both computerized and visual analyses are typically required. However, most security analysts are not adequately trained in visualization principles and/or methods, which is required for effective visual perception of useful attack information hidden in attack data. Additionally, Honeypot has proven useful in cyberattack research, but no studies have comprehensively investigated visualization practices in the field. In this paper, we reviewed visualization practices and methods commonly used in the discovery and communication of attack patterns based on Honeypot network traffic data. Using the PRISMA methodology, we identified and screened 218 papers and evaluated only 37 papers having a high impact. Most Honeypot papers conducted summary statistics of Honeypot data based on static data metrics such as IP address, port, and packet size. They visually analyzed Honeypot attack data using simple graphical methods (such as line, bar, and pie charts) that tend to hide useful attack information. Furthermore, only a few papers conducted extended attack analysis, and commonly visualized attack data using scatter and linear plots. Papers rarely included simple yet sophisticated graphical methods, such as box plots and histograms, which allow for critical evaluation of analysis results. While a significant number of automated visualization tools have incorporated visualization standards by default, the construction of effective and expressive graphical methods for easy pattern discovery and explainable insights still requires applied knowledge and skill of visualization principles and tools, and occasionally, an interdisciplinary collaboration with peers. We, therefore, suggest the need, going forward, for non-classical graphical methods for visualizing attack patterns and communicating analysis results. We also recommend training investigators in visualization principles and standards for effective visual perception and presentation.
基金Universiti Tunku Abdul Rahman for the fnancial supports and research facilities
文摘In this paper, the synthesis of new mesomorphic benzothiazolyl derivatives, 6-ethoxy-2-[4-（4- alkyloxybenzoyloxy）benzylidenamino]benzothiazoles, is presented. The structures of the title compounds were elucidated using spectroscopic techniques, such as FT-IR, NMR （1H and 13C）, elemental analysis and El-MS. The mesomorphic behaviours of these compounds were determined by differential scanning calorimetric and polarizing optical microscopic techniques. Compounds exhibited nematic and tilted smectic phases upon heating from crystal phase. An obvious odd-even effect was observed in this homologous series.
基金Universiti Tunku Abdul Rahman(UTAR)for the research facilities andfinancial support(No.6202/K06)the Malaysian Toray Science Foundation(No.4359/000)
文摘A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibited an enantiotropic nematic phase. The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties. 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘In this paper, an innovative Genetic Algorithms (GA)-based inexact non-linear programming (GAINLP) problem solving approach has been proposed for solving non-linear programming optimization problems with inexact information (inexact non-linear operation programming). GAINLP was developed based on a GA-based inexact quadratic solving method. The Genetic Algorithm Solver of the Global Optimization Toolbox (GASGOT) developed by MATLABTM was adopted as the implementation environment of this study. GAINLP was applied to a municipality solid waste management case. The results from different scenarios indicated that the proposed GA-based heuristic optimization approach was able to generate a solution for a complicated nonlinear problem, which also involved uncertainty.
