Tien Nguyen - Academia.edu (original) (raw)

Papers by Tien Nguyen

IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2006

Recently, lattice reduction aided (ERA) detectors have been introduced into Vertical Bell-Labs La... more Recently, lattice reduction aided (ERA) detectors have been introduced into Vertical Bell-Labs Layered Space-Time (V-BEAST) systems to obtain nearly optimal bit error rate (BER) performance for only small additional complexity. In this paper, the layer error characteristics of LRA-V-BLAST detectors are analyzed and compared with those of conventional V-BLAST ones. Two important conclusions are drawn for the LRA-V-BLAST detectors. First, the variation of their mean square error (MSE) within each detection iteration is not as large as in conventional V-BLAST detectors. Second, thanks to lattice reduction there exists an inherent sub-optimal detection order from the last to the first layer. These conclusions allow LRA-V-BLAST detectors to avoid optimal ordering to further reduce the complexity. LRA-V-BLAST detectors without optimal ordering are shown to obtain almost the same BER performance of LRA-V-BLAST detector with optimal ordering

Joint International Conference on Optical Internet, and the Australian Conference on Optical Fibre Technology, 2007

A technique to implement frequency measurement photonically using only low-cost DC photodetectors... more A technique to implement frequency measurement photonically using only low-cost DC photodetectors is proposed and a proof of concept implementation is practically demonstrated. Techniques to further reduce cost and extend bandwidth are proposed.

The purpose of this study was to conduct a mixed-methods study, including a phenomenological comp... more The purpose of this study was to conduct a mixed-methods study, including a phenomenological component, to understand the perceived roles of technology coordinators and library media specialists in Hawaii public schools. The purpose of this ...

Journal of hazardous materials, Jan 15, 2010

Millions of people worldwide are at risk from the presence of arsenic in groundwater. In this stu... more Millions of people worldwide are at risk from the presence of arsenic in groundwater. In this study, adsorption equilibrium and long term experiments were carried out to evaluate the performance of iron oxide coated sponge (IOCSp) in arsenic removal. It was found that maximum adsorption capacity of IOCSp for As(III) and As(V) calculated by Sips isotherm was 4.2 and 4.6 mg/g of IOCSp, respectively. A filter packed with small amount of 25 g IOCSp maintained a consistent arsenic removal efficiency of 95% from synthetic solution containing arsenic concentration of as high as 1000 microg/L. This produced a throughput volume of 153 and 178 L of water containing As(III) and As(V), respectively before any need for regeneration or disposal of IOCSp. IOCSp could be regenerated by washing it with NaOH solution. The dynamic (column) adsorption kinetics were successfully predicted by the Thomas and Nikolaidis modified models.

The journal of physical chemistry. B, Jan 12, 2010

Bioresource technology, 2012

The membrane bioreactor system (MBR) with pre-treatment of sponge tray bioreactor (STB) was evalu... more The membrane bioreactor system (MBR) with pre-treatment of sponge tray bioreactor (STB) was evaluated at different operating conditions for treating primary treated sewage (PTS). The result indicated the successful removal of DOC with the efficiency of higher than 95%. The highest nutrient removal efficiency of 83.6% (NH(4)-N) and 75.5% (PO(4)-P) was observed at sludge concentration of 330 mg/L. Specific oxygen uptake rate (SOUR) of activated sludge in MBR kept increasing up to 6 mg O(2)/g VSS h during stage IV. The sludge volume index (SVI) of less than 100mL/g during the operation indicated the good settling property of the sludge. At highest sludge concentration of 5 g/L, trans-membrane pressure (TMP) was increasing dramatically during first 15 d up to 25 kPa; however it was only 6 kPa at lower sludge concentrations. It is concluded that the system showed the highest performance at stage III with sludge concentration of 330 mg/L.

Applied biochemistry and biotechnology, 2012

The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat pr... more The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat primary treated sewage effluent at three different activated sludge concentrations. Polyurethane sponge cubes with size of 1 × 1 × 1 cm were used as attached growth media in the bioreactor. The results indicated the successful removal of organic carbon and phosphorous with the efficiency higher than 98% at all conditions. Acclimatised sponge MBR showed about 5% better ammonia nitrogen removal at 5 and 10 g/L sludge concentration as compared to the new sponge system. The respiration test revealed that the specific oxygen uptake rate was around 1.0-3.5 mgO(2)/gVSS.h and likely more stable at 10 g/L sludge concentration. The sludge volume index of less than 100 mL/g during the operation indicated the good settling property of the sludge. The low mixed liquor suspended solid increase indicated that SSMBR could control the sludge production. This SSMBR was also successful in reducing membrane fouling with significant lower transmembrane pressure (e.g. only 0.5 kPa/day) compared to the conventional MBR system. Further study will be conducted to optimise other operating conditions.

Journal of the American Academy of Dermatology, 2013

Autoinflammation is characterized by aberrant regulation of the innate immune system and often ma... more Autoinflammation is characterized by aberrant regulation of the innate immune system and often manifests as periodic fevers and systemic inflammation involving multiple organs, including the skin. Mutations leading to abnormal behavior or activity of the interleukin 1 beta (IL-1ß)-processing inflammasome complex have been found in several rare autoinflammatory syndromes, for which anticytokine therapy such as IL-1 or tumor necrosis factor-alfa inhibition may be effective. It is becoming clear that features of autoinflammation also affect common dermatoses, some of which were previously thought to be solely autoimmune in origin (eg, vitiligo, systemic lupus erythematosus). Recognizing the pathogenetic role of autoinflammation can open up new avenues for the targeted treatment of complex, inflammatory dermatoses.

Bioresource technology, 2013

A pilot scale membrane bioreactor hybrid system (MBR-HS) was evaluated for municipal wastewater t... more A pilot scale membrane bioreactor hybrid system (MBR-HS) was evaluated for municipal wastewater treatment. This novel system comprised of a granular activated carbon-sponge fluidized bed bioreactor (GACS-FBBR) followed by a submerge membrane bioreactor (MBR) with the capacity of 2 L/min. The results indicated that the MBR-HS could effectively remove 90% DOC and 95% NH₄-N. PO₄-P removal efficiency was remained stable at about 70% throughout the experiment. Specific oxygen uptake rate (SOUR) of activated sludge increased from 0.72 to 2.21 mg O₂/g VSSh for the first 10 days and then followed by a steady stage until the end of experiment. Sludge volume index (SVI) was always below 50 mL/g, demonstrated an excellent settling properties of sludge. The system also showed an achievement in terms of low trans-membrane pressure (TMP) development rate. The TMP increasing rate was only 0.65 kPa/day, suggesting GACS-FBBR can be a promising pre-treatment for MBR.

Journal of the American Academy of Dermatology, 2014

Ecotoxicology and environmental safety, 2014

Encyclopedia of RF and Microwave Engineering, 2005

Wiley Encyclopedia of Electrical and Electronics Engineering, 1999

Severe Skin Diseases in Children, 2013

Encyclopedia of RF and Microwave Engineering, 2005

Wiley Encyclopedia of Electrical and Electronics Engineering, 1999

2014 IEEE International Conference on Software Maintenance and Evolution, 2014

Proceeding of the 33rd international conference on Software engineering - ICSE '11, 2011

Abstract Defects are unavoidable in software development and fixing them is costly and resource-i... more Abstract Defects are unavoidable in software development and fixing them is costly and resource-intensive. To build defect prediction models, researchers have investigated a number of factors related to the defect-proneness of source code, such as code complexity, change complexity, or socio-technical factors. In this paper, we propose a new approach that emphasizes on technical concerns/functionality of a system. In our approach, a software system is viewed as a collection of software artifacts that describe different technical ...

21st International Communications Satellite Systems Conference and Exhibit, 2003

In this paper, a detailed quantitative examination of spectrum packing efficiency of several modu... more In this paper, a detailed quantitative examination of spectrum packing efficiency of several modulation schemes is performed using power spectral analysis. Examples are given for a typical communication satellite uplink and downlink. From the results of this analysis, the most promising candidate modulation schemes are selected and identified for a more accurate time-domain analysis.

IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2006

Recently, lattice reduction aided (ERA) detectors have been introduced into Vertical Bell-Labs La... more Recently, lattice reduction aided (ERA) detectors have been introduced into Vertical Bell-Labs Layered Space-Time (V-BEAST) systems to obtain nearly optimal bit error rate (BER) performance for only small additional complexity. In this paper, the layer error characteristics of LRA-V-BLAST detectors are analyzed and compared with those of conventional V-BLAST ones. Two important conclusions are drawn for the LRA-V-BLAST detectors. First, the variation of their mean square error (MSE) within each detection iteration is not as large as in conventional V-BLAST detectors. Second, thanks to lattice reduction there exists an inherent sub-optimal detection order from the last to the first layer. These conclusions allow LRA-V-BLAST detectors to avoid optimal ordering to further reduce the complexity. LRA-V-BLAST detectors without optimal ordering are shown to obtain almost the same BER performance of LRA-V-BLAST detector with optimal ordering

Joint International Conference on Optical Internet, and the Australian Conference on Optical Fibre Technology, 2007

A technique to implement frequency measurement photonically using only low-cost DC photodetectors... more A technique to implement frequency measurement photonically using only low-cost DC photodetectors is proposed and a proof of concept implementation is practically demonstrated. Techniques to further reduce cost and extend bandwidth are proposed.

The purpose of this study was to conduct a mixed-methods study, including a phenomenological comp... more The purpose of this study was to conduct a mixed-methods study, including a phenomenological component, to understand the perceived roles of technology coordinators and library media specialists in Hawaii public schools. The purpose of this ...

Journal of hazardous materials, Jan 15, 2010

Millions of people worldwide are at risk from the presence of arsenic in groundwater. In this stu... more Millions of people worldwide are at risk from the presence of arsenic in groundwater. In this study, adsorption equilibrium and long term experiments were carried out to evaluate the performance of iron oxide coated sponge (IOCSp) in arsenic removal. It was found that maximum adsorption capacity of IOCSp for As(III) and As(V) calculated by Sips isotherm was 4.2 and 4.6 mg/g of IOCSp, respectively. A filter packed with small amount of 25 g IOCSp maintained a consistent arsenic removal efficiency of 95% from synthetic solution containing arsenic concentration of as high as 1000 microg/L. This produced a throughput volume of 153 and 178 L of water containing As(III) and As(V), respectively before any need for regeneration or disposal of IOCSp. IOCSp could be regenerated by washing it with NaOH solution. The dynamic (column) adsorption kinetics were successfully predicted by the Thomas and Nikolaidis modified models.

The journal of physical chemistry. B, Jan 12, 2010

Bioresource technology, 2012

The membrane bioreactor system (MBR) with pre-treatment of sponge tray bioreactor (STB) was evalu... more The membrane bioreactor system (MBR) with pre-treatment of sponge tray bioreactor (STB) was evaluated at different operating conditions for treating primary treated sewage (PTS). The result indicated the successful removal of DOC with the efficiency of higher than 95%. The highest nutrient removal efficiency of 83.6% (NH(4)-N) and 75.5% (PO(4)-P) was observed at sludge concentration of 330 mg/L. Specific oxygen uptake rate (SOUR) of activated sludge in MBR kept increasing up to 6 mg O(2)/g VSS h during stage IV. The sludge volume index (SVI) of less than 100mL/g during the operation indicated the good settling property of the sludge. At highest sludge concentration of 5 g/L, trans-membrane pressure (TMP) was increasing dramatically during first 15 d up to 25 kPa; however it was only 6 kPa at lower sludge concentrations. It is concluded that the system showed the highest performance at stage III with sludge concentration of 330 mg/L.

Applied biochemistry and biotechnology, 2012

The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat pr... more The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat primary treated sewage effluent at three different activated sludge concentrations. Polyurethane sponge cubes with size of 1 × 1 × 1 cm were used as attached growth media in the bioreactor. The results indicated the successful removal of organic carbon and phosphorous with the efficiency higher than 98% at all conditions. Acclimatised sponge MBR showed about 5% better ammonia nitrogen removal at 5 and 10 g/L sludge concentration as compared to the new sponge system. The respiration test revealed that the specific oxygen uptake rate was around 1.0-3.5 mgO(2)/gVSS.h and likely more stable at 10 g/L sludge concentration. The sludge volume index of less than 100 mL/g during the operation indicated the good settling property of the sludge. The low mixed liquor suspended solid increase indicated that SSMBR could control the sludge production. This SSMBR was also successful in reducing membrane fouling with significant lower transmembrane pressure (e.g. only 0.5 kPa/day) compared to the conventional MBR system. Further study will be conducted to optimise other operating conditions.

Journal of the American Academy of Dermatology, 2013

Autoinflammation is characterized by aberrant regulation of the innate immune system and often ma... more Autoinflammation is characterized by aberrant regulation of the innate immune system and often manifests as periodic fevers and systemic inflammation involving multiple organs, including the skin. Mutations leading to abnormal behavior or activity of the interleukin 1 beta (IL-1ß)-processing inflammasome complex have been found in several rare autoinflammatory syndromes, for which anticytokine therapy such as IL-1 or tumor necrosis factor-alfa inhibition may be effective. It is becoming clear that features of autoinflammation also affect common dermatoses, some of which were previously thought to be solely autoimmune in origin (eg, vitiligo, systemic lupus erythematosus). Recognizing the pathogenetic role of autoinflammation can open up new avenues for the targeted treatment of complex, inflammatory dermatoses.

Bioresource technology, 2013

A pilot scale membrane bioreactor hybrid system (MBR-HS) was evaluated for municipal wastewater t... more A pilot scale membrane bioreactor hybrid system (MBR-HS) was evaluated for municipal wastewater treatment. This novel system comprised of a granular activated carbon-sponge fluidized bed bioreactor (GACS-FBBR) followed by a submerge membrane bioreactor (MBR) with the capacity of 2 L/min. The results indicated that the MBR-HS could effectively remove 90% DOC and 95% NH₄-N. PO₄-P removal efficiency was remained stable at about 70% throughout the experiment. Specific oxygen uptake rate (SOUR) of activated sludge increased from 0.72 to 2.21 mg O₂/g VSSh for the first 10 days and then followed by a steady stage until the end of experiment. Sludge volume index (SVI) was always below 50 mL/g, demonstrated an excellent settling properties of sludge. The system also showed an achievement in terms of low trans-membrane pressure (TMP) development rate. The TMP increasing rate was only 0.65 kPa/day, suggesting GACS-FBBR can be a promising pre-treatment for MBR.

Journal of the American Academy of Dermatology, 2014

Ecotoxicology and environmental safety, 2014

Encyclopedia of RF and Microwave Engineering, 2005

Wiley Encyclopedia of Electrical and Electronics Engineering, 1999

Severe Skin Diseases in Children, 2013

Encyclopedia of RF and Microwave Engineering, 2005

Wiley Encyclopedia of Electrical and Electronics Engineering, 1999

2014 IEEE International Conference on Software Maintenance and Evolution, 2014

Proceeding of the 33rd international conference on Software engineering - ICSE '11, 2011

Abstract Defects are unavoidable in software development and fixing them is costly and resource-i... more Abstract Defects are unavoidable in software development and fixing them is costly and resource-intensive. To build defect prediction models, researchers have investigated a number of factors related to the defect-proneness of source code, such as code complexity, change complexity, or socio-technical factors. In this paper, we propose a new approach that emphasizes on technical concerns/functionality of a system. In our approach, a software system is viewed as a collection of software artifacts that describe different technical ...

21st International Communications Satellite Systems Conference and Exhibit, 2003

In this paper, a detailed quantitative examination of spectrum packing efficiency of several modu... more In this paper, a detailed quantitative examination of spectrum packing efficiency of several modulation schemes is performed using power spectral analysis. Examples are given for a typical communication satellite uplink and downlink. From the results of this analysis, the most promising candidate modulation schemes are selected and identified for a more accurate time-domain analysis.