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Development of an Effective Biosorbent by Fungal Immobilization Technique for Removal of Dyes
No full textCharcoal activated carbon was modified through immobilization techniques on fungal biomass. Two fungal strains i.e. Aspergillus niger and Penicillium sp. were selected to immobilize the charcoal activated carbon on fungal biomass. The percentage of biomass production onto activated carbon was 88% for A. niger while it was 75% for Penicillum sp. The results of scanning electron microscope (SEM) showed clear changes between the external surfaces of charcoal activated carbon (AC) and activated carbon immobilized biomass (ACIB) which also indicated the formation of matrix onto AC by fungal mycelia. The ACIBs showed more functional groups as compared to the AC. The functional groups determined by the Fourier transform infrared spectroscopy (FTIR) for the ACIBs by A. niger and Penicillium sp. indicated various changes in achieving additional functional groups (phosphate ester, cyclic ether, alcoholic and phenolic groups) as compared to the AC. The results revealed that AC was morphologically modified by the immobilization techniques. Maximum adsorption capacity by ACIB of A. niger was achieved at a dosage of 15 mg/L for Reactive Black (98.2%), Congo Red (84.6%) and Malachite Green (82.6%) while 20 mg/L dosage was required for Methylene Blue to achieve highest decolorization (92.3%). The results of individual effect of ACIB, AC and biomass on the removal of reactive black 5 showed that maximum removal was obtained at 98.2, 88 and 75% respectively. The modified biosorbents as ACIBs developed by the A. niger and Penicillium sp. in an immobilized culturing process could be a potential agent for decolorization and removal of pollutants
An energy based cluster head selection unequal clustering algorithm with dual sink (ECH-DUAL) for continuous monitoring applications in wireless sensor networks
No full textThe essential sections of the hot spot problem are network lifetime improvements and uniform residual energy distribution in wireless sensor networks (WSN). Clustering of sensor nodes is a significant process that improves network lifetime and energy efficiency ofWSN. Usage of equal cluster sizes in WSN causes more energy to be consumed by the cluster heads when the data is routed to sink thus resulting in hot spot problems. Hence, recent research papers focus on unequal clustering where cluster size increases as the distance to the sink increases. In this paper, cluster heads are selected by modifying energy efficient unequal clustering mechanism (EEUC). This process is done in two ways. Firstly, in EEUC, final cluster heads are selected based on the residual energy of the randomly selected tentative cluster heads. In our algorithm, tentative cluster head is selected based on energy based timer, residual energy, node IDs and trust value. Final cluster head selection approach selects final CHs based on competition range, node degree and head count. Secondly, in applications like continuous monitoring, usage of static sink causes the clusters near the sink to die out faster, as the cluster heads in these clusters form the fixed path for data routing, hence resulting in hot spot problems. In this work, an energy based cluster head selection unequal clustering algorithm (ECH-DUAL) using dual (static and mobile) sink is proposed. The simulation shows that proposed system (ECHDUAL) improves network lifetime of continuous monitoring wireless sensor networks significantly over EEUC
Implementation of vision-assisted path planning system for bulk die sorting in semiconductor industry
No full textSemiconductor integrated circuits (IC) are found in all of today’s electronic devices. Low cost mass production has enabled electronics to revolutionize the way people live and work. One major operation in IC assembly is die sorting, where individual die is categorized by grade. The traditional vision-assisted pick-and-place die sorting approach has high accuracy but low throughput. In this research, a bulk die sorting approach through vision-assisted path planning is studied and implemented. The objective of this system is to provide accurate die classification through vision processing and high die sorting throughput with efficient path planning. The system hardware consists of two parts, motion XY-stage used for wafer planar translation and optical unit used for acquiring wafer images. Firstly, the wafer image is acquired using the image mosaicing method. Then, die classification is performed to obtain the positions of functional and non-functional dies. Subsequently, point and coverage path planning algorithms are applied to determine the optimum path for physical die sorting operation. Overall, the proposed system showed significant improvement in the wafer image quality, low mismatch of dies, and obtained the shortest traversal time and distance for clustering dies by using the combined heuristic cluster with nearest neighbour algorithm. The system showed that the best coverage path planning method is the back-and-forth filling using decelerate-reaccelerate motion in terms of processing time (1.6 s), traversal time (137.2 s) and XY-stage stresses. As a conclusion, through the integrated implementation of hardware and software encompassing wafer image acquisition, die classification and path planning, the die sorting system is capable of achieving accurate die sorting with high throughput
Repeated liver stiffness measurement compared with paired liver biopsy in patients with non-alcoholic fatty liver disease
No full textIntroduction: The value of repeated liver stiffness measurement (LSM) in non-alcoholic fatty liver disease (NAFLD) has not been shown before. Methods: A longitudinal study of biopsy-proven NAFLD patients was conducted at the Asian tertiary hospital from November 2012 to January 2017. Patients with paired liver biopsies and LSM were followed prospectively for liver-related and non-liver related complications, and survival. Results: The data for 113 biopsy-proven NAFLD patients (mean age 51.3 ± 10.6 years, male 50%) were analyzed. At baseline, advanced fibrosis based on histology and LSM was observed in 22 and 46%, respectively. Paired liver biopsy and LSM at 1-year interval was available in 71 and 80% of patients, respectively. High-risk cases (defined as patients with advanced fibrosis at baseline who had no fibrosis improvement, and patients who developed advanced fibrosis on repeat assessment) were seen in 23 and 53% of patients, based on paired liver biopsy and LSM, respectively. Type 2 diabetes mellitus was independently associated with high-risk cases. The median follow-up was 37 months with a total follow-up of 328 person-years. High-risk cases based on paired liver biopsy had significantly higher rates of liver-related complications (p = 0.002) but no difference in other outcomes. High-risk patients based on paired LSM had a significantly higher rate of liver-related complications (p = 0.046), cardiovascular events (p = 0.025) and composite outcomes (p = 0.006). Conclusion: Repeat LSM can predict liver-related complications, similar to paired liver biopsy, and may be useful in identifying patients who may be at an increased risk of cardiovascular events. Further studies in a larger cohort and with a longer follow-up should be carried out to confirm these observations
Training preparation and the professional development of principals in Henan Province, China: formal and informal learning
No full textPrincipal preparation and training is generally viewed as an important contributor to school and system improvement. While the international evidence based on leadership and leadership development is extensive, contemporary accounts of principal preparation in a number of Asian countries are not widespread. This article outlines the findings from a small-scale, exploratory investigation of principal preparation and training in one province in China. Open-ended questionnaire and interview data were collected from a sample of secondary school principals in Henan Province in China, as part of a larger comparative study. The findings show that while principals in this province appreciate their formal training, they also seek out other sources of informal preparation to assist them in their fulfilling their many obligations and responsibilities. The data also highlight that many principals in China are finding the demands of their formal leadership role very challenging, particularly in delivering, contemporary reforms such as the new curriculum. The article concludes by proposing that for principals in China, there are some contradictions and tensions associated with the current demands of this leadership role
Impact of Sustainability Balanced Scorecard Types on Environmental Investment Decision-Making
No full textInvestment decision-making based on aspects of sustainability is gaining importance among organizations around the globe. In this context, there is a need for quality investment decisions, which require sufficient knowledge among organizational managers about managing sustainability information to achieve environmental objectives that meet stakeholder expectations. This has led to the emergence of organizational performance measuring tools such as the Sustainability Balanced Scorecard, which integrates the environmental perspective into the traditional Balanced Scorecard. Using experimental research method, the objective of this study is to investigate the indirect effect of Eco-efficiency knowledge and Sustainability Balanced Scorecard knowledge as mediators influencing the relationship between Sustainability Balanced Scorecard types and their impact on environmental investment decision-making. Findings of the current research are based on 60 respondents who were randomly assigned to one of the following two types of Sustainability Balanced Scorecard architecture: (1) environmental data embedded within the traditional Balanced Scorecard perspectives; and (2) standalone environmental data as an additional fifth perspective along with the traditional Balanced Scorecard architecture. The traditional Balanced Scorecard without any information on environmental perspective is included in the experiment as the control condition. The findings indicate that the combined effect of ecoefficiency knowledge and Sustainability Balanced Scorecard knowledge has a significant positive influence on the relationship between the Balanced Scorecard type versus Sustainability Balanced Scorecard type and environmental investment decision-making
Q-switched erbium-doped fiber laser using MoS 2 deposited side-polished D-shape fiber
No full textA stable Q-switched erbium doped fiber laser (EDFL) emitting at 1560 nm is demonstrated by using molybdenum sulfide (MoS 2 ) material coated onto a side-polished D-shape fiber as a saturable absorber (SA). By incorporating the MoS 2 SA into the laser cavity, a stable Q-switching pulses train output centered at 1560 nm is observed at threshold pump power of 14.9 mW. As the pump power is gradually increased from 14.9 to 50.5 mW, the repetition rate of the generated pulse increases from 31.1 kHz to 75.5 kHz, while the pulse width decreases from 14.52 µs to 6.76 µs. Under a pump power of 50.5 W, an average output power of 2.47 W and a pulse energy of 32.7 nJ is obtained. This MoS 2 based SA is simple, robust and reliable and thus suitable for making a portable pulse laser source
A novel waveguide design that produces an elongated laser beam output for soft tissue ablation
No full textIn this work, we have fabricated and experimentally demonstrated a purpose-built 365 μm optical fibre device that produces an elongated laser beam output for efficient tissue ablation. The proposed fibre device has several advantages and potential for application in surgery. The off-axis firing beam from the fibre lowers the risk of past-pointing injury as compared to forward-firing laser fibres. A pulsed Holmium:YAG (Ho:YAG) laser at a wavelength of 2.1 μm at a repetition rate of 6 Hz was used in this experiment. The fibre was angle-polished at ∼25° to create a deviated beam that resulted in a longer ablation length ∼1 cm; it was five times longer than the forward-firing laser output and had sufficient energy intensity to perform an ablation rate of 7.7 μm per pulse. Fresh squid (Cephalopod Theutida) was used as the biological tissue to determine the ablation length and crater. The threshold radiant exposure, Φth for tissue ablation was estimated to be 1.84 J/cm2 and the effective divergence angle was ∼24° by using the highest pulsed energy of 1.8 J
Social Networking Site Adoption in Malaysia and Indonesia
No full textThis study employed the Model of Technology Preference (MTP) to investigate the antecedents of behaviour intention to adopt Social Networking Site (SNS) for communication after considering individual’s preference factor. This study used quantitative approach where surveys were conducted in Malaysia and Indonesia. Self-administered questionnaires were distributed to SNS users in big cities of both countries that lead to a total of 1037 valid responses. The data were analysed using Structural Equation Model (SEM) to measure model fit and to conduct structural modelling. The results in general support that Attribute-Based Preference (ATRP) significantly affects Attitude-Based Preference (ATTP), which also mediates that effect with Behaviour Intention (BI) of using SNS. Nonetheless, the findings from the two countries vary with regard to the attributes that affect the ATTP and the effect of ATTP on BI and Attitude (ATT) towards SNS. Malaysians tend to use SNS for communication due to the availability of options for their preferred technology. This could be explained by the higher pragmatic and masculinity index of the Malaysian culture, which they tend to exhibit in their actions. In contrary, Indonesians tend to defer using the SNS and create another level of attitude before the actual usage
Career administration, proactive behavior and career satisfaction: A mediating relationship
No full textThe need to improve the human aspect has never been found imperative on organizations other than at a time when personnel are challenged daily with efficiency dropping and job performance in low ebb. Hence, it is vital for this study to examine the relationship between career administration, proactive behavior and career satisfaction. A survey method was conducted and 132 self-report questionnaires were collected from employees in a renowned manufacturing firm in the Malaysian petroleum industry. The survey has two significant results: (i) Relationship between job autonomy and proactive behavior has a positive and significant correlation to career satisfaction. (ii) Relationship between transformational leadership and proactive behavior has a positive and significant correlation to career satisfaction. The result posits that proactive behavior is key variable linking career administration to organizational career satisfaction. Implications from this survey and recommendations for future research are made