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1.Urbanization Impacts the Physicochemical Characteristics and Abundance of Fecal Markers and Bacterial Pathogens in Surface Water

Author:Yuan, TM;Vadde, KK;Tonkin, JD;Wang, JJ;Lu, J;Zhang, ZM;Zhang, YX;McCarthy, AJ;Sekar, R


Abstract:Urbanization is increasing worldwide and is happening at a rapid rate in China in line with economic development. Urbanization can lead to major changes in freshwater environments through multiple chemical and microbial contaminants. We assessed the impact of urbanization on physicochemical characteristics and microbial loading in canals in Suzhou, a city that has experienced rapid urbanization in recent decades. Nine sampling locations covering three urban intensity classes (high, medium and low) in Suzhou were selected for field studies and three locations in Huangshan (natural reserve) were included as pristine control locations. Water samples were collected for physicochemical, microbiological and molecular analyses. Compared to medium and low urbanization sites, there were statistically significant higher levels of nutrients and total and thermotolerant coliforms (or fecal coliforms) in highly urbanized locations. The effect of urbanization was also apparent in the abundances of human-associated fecal markers and bacterial pathogens in water samples from highly urbanized locations. These results correlated well with land use types and anthropogenic activities at the sampling sites. The overall results indicate that urbanization negatively impacts water quality, providing high levels of nutrients and a microbial load that includes fecal markers and pathogens.

2.Minimum-Backflow-Power Scheme of DAB-Based Solid-State Transformer With Extended-Phase-Shift Control

Author:Shi, HC;Wen, HQ;Chen, J;Hu, YH;Jiang, L;Chen, GP;Ma, JM


Abstract:As key component for the flexible dc distributed power system, the dual active bridge (DAB)-converter-based solid-state transformer (SST) with high efficiency for a wide operating range is essential. However, with the traditional phase-shift control, high backflow power and current stress will significantly affect the conversion efficiency. In this paper, the backflow power characteristics in both sides of DAB-based SST converters are comprehensively analyzed. On this basis, complete transmission power, backflow power, and peak current mathematical models are established. Then, a minimum-backflow-power-based extended-phase-shift control strategy is proposed with the determination of optimal phase-shift pairs by using the Karush-Kuhn-Tucker function for various scenarios. The backflow power and current stress curves with different algorithms are compared. It shows the proposed control can improve the output power regulation flexibility, minimize the backflow power, and improve the efficiency in wide operating range. Finally, a DAB-based SST prototype was developed and the experimental results verified the effectiveness of the proposed control strategy.

3.Psychometric Evaluation of Chinese-Language 44-Item and 10-Item Big Five Personality Inventories, Including Correlations with Chronotype, Mindfulness and Mind Wandering

Author:Carciofo, R;Yang, JY;Song, N;Du, F;Zhang, K

Source:PLOS ONE,2016,Vol.11

Abstract:The 44-item and 10-item Big Five Inventory (BFI) personality scales are widely used, but there is a lack of psychometric data for Chinese versions. Eight surveys (total N = 2,496, aged 18-82), assessed a Chinese-language BFI-44 and/or an independently translated Chinese-language BFI-10. Most BFI-44 items loaded strongly or predominantly on the expected dimension, and values of Cronbach's alpha ranged .698-. 807. Test-retest coefficients ranged .694-.770 (BFI-44), and .515-.873 (BFI-10). The BFI-44 and BFI-10 showed good convergent and discriminant correlations, and expected associations with gender (females higher for agreeableness and neuroticism), and age (older age associated with more conscientiousness and agreeableness, and also less neuroticism and openness). Additionally, predicted correlations were found with chronotype (morningness positive with conscientiousness), mindfulness (negative with neuroticism, positive with conscientiousness), and mind wandering/daydreaming frequency (negative with conscientiousness, positive with neuroticism). Exploratory analysis found that the Self-discipline facet of conscientiousness positively correlated with morningness and mindfulness, and negatively correlated with mind wandering/daydreaming frequency. Furthermore, Self-discipline was found to be a mediator in the relationships between chronotype and mindfulness, and chronotype and mind wandering/daydreaming frequency. Overall, the results support the utility of the BFI-44 and BFI-10 for Chinese-language big five personality research.

4.Morningness-eveningness and affect: the mediating roles of sleep quality and metacognitive beliefs

Author:Carciofo, R


Abstract:Morningness (a preference for earlier rise and bed times) is associated with well-being, better sleep quality, and positive affect, while eveningness is associated with poor sleep quality, negative mood, maladaptive behaviours, and psychological disorder. The current study investigated: (1) whether eveningness is associated with more maladaptive metacognitive beliefs; (2) whether maladaptive metacognitive beliefs and sleep quality are related to associations between morningness-eveningness and affect. An online survey with questionnaire measures of morningness-eveningness, affect, sleep quality, and metacognitive beliefs was completed by 591 undergraduate students. More morningness correlated with more positive affect, while more eveningness correlated with more negative affect and poor sleep quality. Eveningness also showed small correlations with having less cognitive confidence and with metacognitive beliefs about uncontrollable thoughts. Mediation analysis showed that cognitive confidence and beliefs about uncontrollable thoughts, together with poor sleep quality (especially subjective sleep quality and daytime dysfunction), were mediators in the relationships between morningness-eveningness and both negative affect and positive affect. These findings suggest that metacognitive beliefs may be an important consideration in understanding the associations between morningness-eveningness and well-being.

5.Relic DNA does not obscure the microbial community of paddy soil microbial fuel cells

Author:Gustave, W;Yuan, ZF;Sekar, R;Toppin, V;Liu, JJY;Ren, YX;Zhang, J;Chen, Z


Abstract:Soil Microbial Fuel Cells (MFCs) are devices that can generate electricity by using the flooded soil's anode respiring microbial consortium. When the MFC starts to work, the microbial community in the anode vicinity rapidly changes. This shift in the microbial community results in many dead cells that may release their DNA (relic DNA) and obscure culture independent estimates of microbial community composition. Although relic DNA is expected to increase in MFCs, the effect of relic DNA has not been investigated in the soil MFCs system. In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4%% vs 23.6%%) and the class Deltaproteobacteria (16.8%% vs 5.9%%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0%% vs 28.7%%) and the class Sphingobacteria (5.3%% vs 7.0%%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7%% vs 52.3%%) and Bathyarchaeota (10.1%% vs 17.3%%) were significantly lower in the MFCs, whereas the phylum Woesearchaeota (DHVEG6) (24.4%% vs 19.4%%) was slightly enhanced. Moreover, the results showed that relic DNA can affect the relative abundance of Geobacter and Candidatus Methanoperedens, however, it has no significant effects on the microbial community structure. These results indicate that MFCs can influence the soil microbial community profile, nevertheless the relic DNA generated has minimum effect on the culture independent estimates of microbial community composition. (C) 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

6.Towards a ranking approach for sensor services using primitive cognitive network process

Author:Yuen, KKF;Wang, W


Abstract:The Abstracting sensor capabilities as services is a promising approach to support interoperability and scalability in Internet of Things based applications; however, ranking and selecting these dynamic and large number of real-world services in real-time is a challenging problem, which involves decision making in the presence of multiple criteria. This paper demonstrates an application of the Primitive Cognitive Network Process (P-CNP) to the sensor service ranking with respect to multiple Quality-of-Service criteria.

7.Usable Authentication Mechanisms for Mobile Devices: An Exploration of 3D Graphical Passwords

Author:Yu, Z;Olade, I;Liang, HN;Fleming, C


Abstract:Current authentication systems in mobile devices such as smart phones have many shortcomings. Users tend to use simple textual passwords such as PINs, which are easily cracked by intruders. Meanwhile, graphical passwords suffer from shoulder surfing attack In this paper, a new authentication system using 3D graphical passwords, will be proposed and tested to offer more security for mobile devices. This authentication system allows users to interact with the 3D objects in a 3D virtual environment and these actions are tracked in the virtual environment and used to create unique passwords. Based on the previous studies of the 3D password scheme, this paper developed a simple testing program that enables users to create their own 3D password easily. At the end of the paper, some improvements of the program and this authentication system are discussed.

8.Application of Hough Transform Feature Extraction to Reduce Angular Vibration in Images Captured from Moving Objects

Author:Afolabi, D;Man, KL;Liang, HN;Zhang, N;Lim, EG;Wan, KY


Abstract:This paper details an ongoing research aimed at developing computational approach to reducing/eliminating vibration and light glare in images captured by digital cameras especially when the scene contains moving objects or the camera is mounted on a moving vehicle / flying drone. The algorithms developed are focused at real-time image acquisition where the enhanced/corrected images are need almost immediately after they are captured. The results show that these methods of reducing the stated problems are effective and it can be further developed for various applications.

9.Clinical Validity and Reliability of the Malay Language Translations of Gastroesophageal Reflux Disease Questionnaire and Quality of Life in Reflux and Dyspepsia Questionnaire in a Primary Care Setting

Author:Vadivelu, S;Ma, ZF;Ong, EW;Hassan, N;Hassan, NFHN;Aziz, SHSA;Kueh, YC;Lee, YY


Abstract:Background: Gastroesophageal Reflux Disease Questionnaire (GERDQ) and Quality of Life in Reflux and Dyspepsia Questionnaire (QOLRAD) are reliable tools for evaluation of GERD. Aim: We aimed to test validity and reliability of Malay language translations of GERDQ and QOLRAD in a primary care setting. Methods: The questionnaires were first translated into the Malay language (GERDQ-M and QOLRAD-M). Patients from primary care clinics with suspected GERD were recruited to complete GERDQ-M, QOLRAD-M, and Malay-translated 36-item short-form health survey (SF-36 or SF36-M), and underwent endoscopy and 24-h pH-impedance test. Results: A total of 104 (mean age 47.1 years, women 51.9%%) participants were enrolled. The sensitivity and specificity for GERDQ-M cut-off score >= 8 were 90.2 and 77.4%%, respectively. Based on this cut-off score, 54.7%% had a high probability of GERD diagnosis. GERD-M score >= 8 vs. <8 was associated with erosive esophagitis (p < 0.001), hiatus hernia (p = 0.03), greater DeMeester score (p = 0.001), and Zerbib scores for acid refluxes (p < 0.001) but not non-acid refluxes (p = 0.1). Mean total scores of QOLRAD-M and SF-36-M were correlated (r = 0.74, p < 0.001). GERDQ-M = 8, erosive esophagitis, and DeMeester >= 14.72 were associated with impaired QOLRAD-M in all domains (all p < 0.02) but this was not seen with SF-36. Conclusions: GERDQ-M and QOLRAD-M are valid and reliable tools applicable in a primary care setting. (C) 2018 S. Karger AG, Basel

10.The effects of the bioanode on the microbial community and element profile in paddy soil

Author:Williamson, G;Chen, Z


Abstract:In paddy soil the reductive dissolution of iron oxide and the availability of organic matter plays an important role in arsenic release under anaerobic conditions. Microbial fuel cells have been shown to reduce organic matter (OM) content and the rate in which this occurs strongly relate to the external resistance applied. In this study we investigated the effects of bioanode operating at different external resistance on the paddy soil microbial community and iron and arsenic concentration. The results show that MFC can be used to reduce soil pore water iron and arsenic concentration and the extent in which this occurs depend on the external resistance applied. The MFC is able to mitigate arsenic release by decreasing organic matter availability. Furthermore, our finding shows that external resistance had a significant influence on the bacterial community composition that develop on the bioanode however only had minimal effect on the community of the bulk soil. These findings suggest that the sMFC can influence the iron and arsenic concentration by reducing OM content and the microbial community that develop in the bioanode vicinity.

11.Macroinvertebrate drift-benthos trends in a regulated river

Author:Tonkin, JD;Death, RG


Abstract:Downstream drift plays a fundamental role in the spatial distribution and community structure of lotic macroinvertebrates. We sampled both benthic and drifting macroinvertebrates at 15 sites, in three sections of river with varying flow alteration along the Tongariro River, New Zealand. Our objectives were to examine whether (i) benthic and drift density were linearly related throughout the river, (ii) the presence of dams affected the propensity of macroinvertebrates to drift, and (iii) drift propensity was related to benthic periphyton biomass or natural longitudinal patterns down the river. More taxa were collected from the drift than the benthos, although drift and benthic samples were generally taxonomically similar, despite some structural differences. Nonetheless, differences were evident between the major groups when assessing density and relative abundance links between the benthos and drift. The presence of dams did not affect the propensity of macroinvertebrates to drift on the whole, nor was propensity affected by periphyton biomass or distance from source. These results suggest that although altered periphyton biomass in downstream sections in the Tongariro River is altering the composition of benthic and drifting macroinvertebrates, drift propensity is unaffected. However, some deviations from linear relationships between benthic and drift density are evident suggesting these links may be taxon specific.

12.Modeling and Verification of NCL Circuits Using PAT

Author:Ma, JM;Man, KL;Lim, EG;Zhang, N;Lei, CU;Guan, SU;Jeong, TT;Seon, JK

Source:CEIS 2011,2011,Vol.15

Abstract:NULL Conventional Logic (NCL) is a Delay-Insensitive (DI) clockless paradigm and is suitable for implementing asynchronous circuits. Efficient methods of analysis are required to specify and verify such DI systems. Based on Delay Insensitive sequential Process (DISP) specification, this paper demonstrates the application of formal methods by applying Process Analysis Toolkit (PAT) to model and verify the behavior of NCL circuits. A few useful constructs are successfully modeled and verified by using PAT. The flexibility and simplicity of the coding, simulation and verification shows that PAT is effective and applicable for NCL circuit design and verification. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011]

13.Light attenuation - a more effective basis for the management of fine suspended sediment than mass concentration?

Author:Davies-Colley, RJ;Ballantine, DJ;Elliott, SH;Swales, A;Hughes, AO;Gall, MP


Abstract:Fine sediment continues to be a major diffuse pollution concern with its multiple effects on aquatic ecosystems. Mass concentrations (and loads) of fine sediment are usually measured and modelled, apparently with the assumption that environmental effects of sediment are predictable from mass concentrations. However, some severe impacts of fine sediment may not correlate well with mass concentration, notably those related to light attenuation by suspended particles. Light attenuation per unit mass concentration of suspended particulate matter in waters varies widely with particle size, shape and composition. Data for suspended sediment concentration, turbidity and visual clarity (which is inversely proportional to light beam attenuation) from 77 diverse New Zealand rivers provide valuable insights into the mutual relationships of these quantities. Our analysis of these relationships, both across multiple rivers and within individual rivers, supports the proposition that light attenuation by fine sediment is a more generally meaningful basis for environmental management than sediment mass. Furthermore, optical measurements are considerably more practical, being much cheaper (by about four-fold) to measure than mass concentrations, and amenable to continuous measurement. Mass concentration can be estimated with sufficient precision for many purposes from optical surrogates locally calibrated for particular rivers.

14.Directional Motion-based Interfaces for Virtual and Augmented Reality Head-mounted Displays


Source:Proceedings of 2018 International Computers, Signals and Systems Conference, ICOMSSC 2018,2018,Vol.

Abstract:This research, conducts an experiment to investigate whether there is a difference in user performance and preference for two types of head-mounted displays (HMDs) when users need to perform directional motion movements such as moving one foot forward and backward (or leftward or rightward). The two types of HMDs we have considered are virtual reality (VR) and augmented reality (AR), which represent the two most commonly marketed HMDs. The AR device chosen for this research is the Meta 2 while the chosen VR device is the Oculus RIFT CV1. The results of our experiment show that there is a close significant difference on task completion time between AR and VR condition when users perform motion direction tasks. Also, no significant effect has been found on the accuracy of making these motion movements between the AR and VR conditions. In terms of user preference, the results show that there is no significant effect on workload, motion sickness, immersion, and user experience. These results suggest that both AR and VR HMDs are suitable for interfaces that can rely on body motions like tapping on the floor using one foot in any of the directions around the user.

15.The Design of Bus Accessing Timing to NAND Flash Array for High Bandwidth

Author:Cheng, LX;Yang, Y;Liu, YY;Seon, JK;Man, KL


Abstract:To improve the reading and writing speed of NAND flash array with multi-channel and multi-way, and to obtain the highest available bandwidth, an approach is presented in this paper. One mechanism of high efficiency bus accessing timing scheme based on interleaving is introduced into the approach. In pursuance of this timing, flash controllers are able to make every plane in the flash array to be active in parallel. Therefore the transmission ability to and from the bus can be greatly improved. Utilizing this approach, the accessing efficiency to the NAND flash array will be pushed to a very high level. According to the testing results, as opposed to normal flash bus timing scheme, the data reading efficiency can be increased by 68.5%%, and the data writing efficiency can be increased by 457%%, with the flash bus timing scheme presented in this paper being used. The conclusion can be drawn that the flash bus timing scheme presented in this paper is effective, and the reading and writing at very high speed to the NAND flash array can be realized.


Author:Ma, JM;Man, KL;Krilavicius, T;Guan, SU;Jeong, T


Abstract:Estimating arithmetic is a design paradigm for DSP hardware. By allowing structurally incomplete arithmetic circuits to occasionally perform imprecise calculations, higher performance can be achieved in many different electronic systems. This paper presents a potential useful approach to implement tree multipliers by using estimating arithmetic. Experimental results show the applicability and effectiveness of the proposed approach.

17.An exploration of techniques for off-screen content interaction in mobile devices

Author:Shen, T;Liang, HN;Liu, D;Man, KL


Abstract:This paper is an attempt to explore new ways for allowing interaction with mobile devices, such as smartphones and tablets. Mobile devices have become very popular in a relatively short time. Their popularity is mainly due to the portability and until very recently their ease-of-interaction through the touch-enabled screen when compared to older devices. Their portability comes with a trade-off: the small screen through which users can interact with their content. The small size screen can limit significantly the amount of content they can interact with, and also the manner in which this interaction is carried out. In this research, we explore the ways of extending the interaction space of these devices. We assess if, how well, and what mechanisms are possible for enabling users to interact with content located off the screen. In this paper, we report our approach and some early results of experiments we have conducted.

18.Classified Vector Quantisation and population decoding for pattern recognition

Author:Bailing Zhang;Sheng-Uei Guan

Source:International journal of artificial intelligence and soft computing: IJAISC,2009,Vol.

Abstract:Learning Vector Quantisation (LVQ) is a method of applying the Vector Quantisation (VQ) to generate references for Nearest Neighbour (NN) classification. Though successful in many occasions, LVQ suffers from several shortcomings, especially the reference vectors are prone to diverge. In this paper, we propose a Classified Vector Quantisation (CVQ) to establish VQ for classification. By CVQ, each data category is represented by its own codebook, which can be implemented by some learning algorithms. In classification process, each codebook offers a generalised NN. The examples of handwritten digit recognition and offline signature verification are used to demonstrate the efficiency of the proposed scheme.



Source:ACM International Conference Proceeding Series,2020,Vol.

20.Concurrent Error Detection Adder Based On Two Paths Output Computation

Author:Khedhiri, C;Karmani, M;Hamdi, B;Man, KL


Abstract:This paper presents a concurrent error detection (CED) technique for a bit-slice of a full-adder. The proposed method involves computing the sum and carry bits in two alternative ways so that transient faults will be detected by comparing the results (Sum and Carry out) obtained from the two computing paths. This technique attempts to reduce the amount of extra hardware and cost of the circuit. In order to avoid the problem of extra time we will propagate the result when the first computation is finished so that dependent computation can commence execution as soon as possible. To prove the efficiency of the proposed method, the circuit is simulated in standard CMOS 32nm technology and some transient faults are voluntary injected in the Layout of the circuit. The proposed design involves 12.12%% saving in transistor count compared to DMR (Dual Modular Redundancy) style design.
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