Enhancing data centre networking using energy aware optical interconnects

In a fast changing world where information technology drives economic prosperity, the number of data centres has grown significantly in the past few years. These data centres require large amount of energy in order to meet up with increasing demands. An overview of energy efficient optical interconnects as a means of reducing energy consumption without compromising speed and accuracy was presented. New methods by which energy efficiency can be achieved using OCDMA multiplexing techniques for future optical interconnections were discussed. We also presented some challenges that might inhibit effective implementation of the OCDMA multiplexing scheme

In situ method for power re-equalization of wavelength pulses inside of OCDMA codes

A simple in-situ method to equalize power among individual wavelengths pulses representing two-dimensional wavelength-hopping time-spreading OCDMA code originally generated by a fibre Bragg grating-based OCDMA encoder is presented. Experimental data obtained in a field-based multiuser OCDMA testbed shows that applying this method results in system performance enhancements which was demonstrated by observing improved bit error rate (BER) during the field trials

Investigation of all-optical switching OCDMA testbed under the influence of chromatic dispersion and timing jitter

First part of this paper presents an all-optical switching OCDMA testbed investigation under the influence of the residual chromatic dispersion resulted from different locations of the receiving terminal. The investigation was carried out using incoherent 2D-WH/TS OCDMA codes based on picosecond pulses at OC-48 (2.5Gb/s) data rate. The testbed itself is based on a fully chromatic dispersion compensated (with sub-picosecond accuracy) 17 km bidirectional fiber link connecting University of Strathclyde and Glasgow University. We have found that a high performance penalty in the form of BER deterioration was incurred when even a relatively short length of optical fiber was added to a fully compensated transmission link in order to relocate the receiving terminal (we tested increments up to 275m of SMF-28). Second part of this paper reports on the testbed performance when an OCDMA receiver with built in all-optical clock recovery was implemented to mitigate the detrimental effects of the link timing jitter on the picosecond switching based all-optical time gate

Effect of variations in environmental temperature on 2D-WH/TS OCDMA code performance

Extensive research has been carried out on the performance investigation of two-dimensional wavelength hopping/time spreading optical code division multiple access (OCDMA) codes, which are based on picosecond multiwavelength pulses under the influence of temperature variations resulting from changing environmental conditions. Equations have been derived to theoretically evaluate the extent to which such temperature changes will degrade the overall OCDMA system performance. To mitigate these negative effects on the OCDMA system, several steps have been introduced to improve the code robustness. System design improvements have then been investigated. We also found they would help to improve the spectral efficiency

Wireless temperature sensor network

Sensor networks are being widely deployed for measurement, detection and surveillance applications. Today, humidity becomes very important in many aspects especially in manufacturing industry. Therefore, the use of tools or systems that can monitor the humidity level is very significant. Sensor networks can be used to identify larger trends in temperature which could be used to report energy usage, HVAC problems, computer failures based on high temperatures and fire evacuation route reporting. This project presents a design of Wireless Temperature Sensor Network that capable to monitor the humidity level. This Wireless Temperature Sensor Network comprises of two parts; temperature detection and monitoring. The detection section will sense the temperature and transmit the signal to the monitoring section. All the sensors are connected mote to mote to ensure that each mote can communicate and exchange the data with each other. The collection of temperature data would be obtained by a sensor network. The data was collected using a temperature sensor network connected to a stand-alone computer. This approach can makes the monitoring process becomes more efficient and cost effective. The data (temperature level) will be display by using GUI. In the case of mote to mote system, the GUI capable to display the overall level of temperature

A DYNAMIC SIR MODEL FOR THE SPREAD OF NOVEL CORONAVIRUS DISEASE 2019 (COVID-19) IN MALAYSIA

The emergence of the first coronavirus disease 2019 (COVID-19) case in Malaysia has increased the number of infected cases. Hence, this study proposes a Susceptible-Infected-Recovery (SIR) epidemiological model of the COVID-19 epidemic to portray the outbreak's situation. The SIR model is numerically solved using the Fourth-order Runge-Kutta (RK4) method in Matlab®. The Euler method verifies that the graphical results of the SIR model are reliable and valid. In addition, this study analyses the stability of disease-free and endemic equilibriums of the SIR model by the Jacobian matrix. The results show the outbreak for phase 1 occurs in the first 100 days of the phase due to the increased infected cases in early March 2020. As for phase 2, the increases of infected cases in wave 2 make the outbreak occur throughout phase 2, with R0 being higher than phase 1. The infected population for phase 3 shows asymptotic behavior even though the infection rate increases, but the recovery rate is much higher than in phase 2. The local stability of the endemic equilibrium of all phases exists since the value of R0 is more than one. The system is locally asymptotic stable for all three phases since the obtained eigenvalues are real and negative

Experimental Performance Analysis Of Macrobending Loss Characteristics In Polymer Optical Fiber

An investigation of bending loss characteristics of a Polymer Optical Fiber is presented experimentally. Loss of optical power in an optical fiber due to bending has been investigated for a wavelength of 650 nm. Variations of bending loss with different lengths have been measured, with a number of radii of curvature. Bending Loss equations for short length POF is proposed, which shows the dependence of bending loss on the curvature radii. The equations can be an initial reference or aid in predicting the loss contributes by the polymer optical fiber

Characteristics of human spermatozoa harvested in culture media with and without serum proteins

This study was aimed to determine the efficiency of synthetic protein-free media in spermatozoa washing, preparation and retention of the activity of washed spermatozoa over short periods in vitro. Normozoospermic semen samples (n = 71) were equally apportioned and washed using synthetic protein-free medium (PFM), minimum essential medium + HSA (MEM) or commercial protein-containing medium (CPC). Washed spermatozoa were cultured in vitro using PFM, MEM or CPC media and held for 24 hrs at 4°C, 15°C, 22°C or 37°C. Spermatozoa activity was evaluated at 0 hr, 4 to 7 hrs and 24 hrs post-wash. The effects of PFM on spermatozoa motility, vitality, membrane integrity and DNA fragmentation level were not significantly different from that of MEM and CPC media at 0 hr, 4 to 7 hrs and 24 hrs post-wash in vitro. Synthetic PFM, MEM and CPC retained spermatozoa activity highest when specimen were held at 22°C and it was significantly higher (p 0.05) were noted in spermatozoa DNA fragmentation (SDF) levels when specimen were held at 22°C or 37°C at 4 to 7 hrs and also after 24 hrs post-wash in vitro in all media. The use of synthetic PFM as an alternative to the commercial protein-containing media in human spermatozoa washing and preparation procedure for an efficient and safer (Assisted Reproduction Technology) ART outcome. Spermatozoa activity can be successfully retained at room temperature post-wash over short periods; spermatozoa may lose viability rapidly if held for long hours at 37°C in all media

Religious value as the main influencing factor to customers patronizing Islamic bank

Islamic bank in Malaysia was established in 1983. The development of the Islamic bank is increasingly challenging with the participation of more conventional banks offering banking products and services based on Islamic principles. This paper analyses the factors considered as important by academicians in public institutions of higher learning in selecting a particular bank. A sample of 250 Islamic bank customers in seven Malaysian Public Institutions of Higher Learning in the East Coast of Peninsular Malaysia was surveyed. The study revealed that religious value appears to be the most important factor. Other factors perceived to be important include ATM services, financial security, cost and benefit and attractiveness. It is to be concluded that, even though there are a lot of determining factors the religious value practised by the consumers plays a vital role in influencing them to patronize Islamic banking. For future studies, it is recommended to add more samples from other categories of consumers from different parts of the country

Comparative High-K Material Gate Spacer Impact In DG-FinFET Parameter Variations Between Two Structures

This paper investigates the impact of the high-K material gate spacer on short channel effects (SCEs) for the 16 nm double-gate FinFET (DG-FinFET), where depletion-layer widths of the source-drain corresponds to the channel length. Virtual fabrication process along with design modification throughout the study and its electrical characterization is implemented and significant improvement is shown towards the altered structure design whereby in terms of the ratio of drive current against the leakage current (ION/IOFF ratio), all three materials tested being S3N4, HfO2 and TiO2 increases from the respective 60.90, 80.70 and 84.77 to 84.77, 91.54 and 92.69. That being said, the incremental in ratio has satisfied the incremental on the drive current as well as decreases the leakage current. Threshold voltage (VTH) for all dielectric materials have also satisfy the minimum requirement predicted by the International Technology Roadmap Semiconductor (ITRS) 2013 for which is at 0.461±12.7% V. Based on the results obtained, the high-K materials have shown a significant improvement, specifically after the modifications towards the Source/Drain. Compared to the initial design made, TiO2 has improved by 12.94% after the alteration made in terms of the overall ION and IOFF performances through the ION/IOFF ratio value obtained, as well as meeting the required value for VTH obtained at 0.464V. The ION from high-K materials has proved to meet the minimum requirement by ITRS 2013 for low performance Multi-Gate technology. © 2019 Institute of Advanced Engineering and Science