Evaluation of High Speed Hardware Multipliers - Fixed Point and Floating point

There is a huge demand in high speed arithmetic blocks, due to increased performance of processing units. For higher frequency clocks of the system, the arithmetic blocks must keep pace with greater requirement of more computational power. Area and speed are usually conflicting constraints so that improving speed results mostly in larger areas. In our research we will try to determine the best solution to this problem by comparing the results of different multipliers. Different sized of two algorithms for high speed hardware multipliers were studied and implemented ie. Parallel multiplier, Bit serial multiplier. The workings of these two multipliers were compared by implementing each of them separately in VHDL. A number of high speed adder designs are developed and algorithm and design of these adders are discussed. The result of this research will help us to choose the better option between serial and parallel multipliers for both fixed point and floating point multipliers to fabricate in different systems. As multipliers form one of the most important components of many systems, analysing different multipliers will help us to frame a better system with area and better speed.DOI:http://dx.doi.org/10.11591/ijece.v3i6.418

SAW Filter Modelling in Matlab for GNSS Receivers

Satellite navigation has enabled a great amount of new application for many users, but a lot of limitations have been observed regarding precision and integrity of navigation signals. Overall signals of different navigation systems (GPS, GALILEO, GLONASS signals) compose Global Navigation Satellite Systems (GNSS) Signal. Each of the satellite system has separate signal characteristics, but each signal needs to be compatible with the others to prevent interferences and attenuations between signals. The processing of all the signals is performed in same receiver. Hence, complex receiver design is required. In GNSS signals different frequencies are used for different satellite navigation systems such as GPS, Galileo and Glonass. When the group delay response is observed in SAW filters it shows that the signals lie on different frequencies have different delays. Manufacturers carried out measurements with respect to carrier wave but they have ignored the spreading codes or modulation. In this research, we will design a model for GNSS SAW filter in Matlab. This model can be use to obserce the delay of the signals. This model will allow the manufacturers to address these problems in the SAW filter software to optimise slope and magnitude of the design which will benefit the users of GNSS all over the world to get more precise positioning.DOI:http://dx.doi.org/10.11591/ijece.v3i5.364

THE STATUS OF HIGHLY ALIEN INVASIVE PLANTS IN PAKISTAN AND THEIR IMPACT ON THE ECOSYSTEM: A REVIEW

Invasive alien species colonize the environment and are aggressively a mediator of change and threaten native biodiversity of Pakistan. Invasive species are the species that has been accidentally or intentionally introduced to a different habitat which may be any species, including its seeds, eggs, spores, or other biological material capable of propagating that species, that is not native to that ecosystem. The introduction of these species likely to cause economic or environmental harm or harm to human health. One day consultative workshop was held at NARC, Islamabad in Pakistan on 17 September 1999, to identify, evaluate, and rank non-native plants that threaten the ecological integrity of wildlands and cropping systems. The focus was on species that are already established in areas that support native ecosystems, such as parks, reserves, wildlife areas, national forests, and rangelands.  Fourteen plant species have been identified through a one-day consultative workshop on Alien Invasive Species.  These plant species include trees and shrubs mainly as well as aquatic plant species.  Key words:- species ,plants , invasive , plant , alien , pollen

Effect of percutaneous mitral vavuloplasty on pregnant mother and foetus--a tertiary care hospital experience from a developing country

This study evaluated the short and long-term consequences of Percutaneous Mitral Valvuloplasty (PMV) in pregnant patients and their offspring, in a tertiary care setting, Karachi, Pakistan. The hospital database was used to retrieve all patients who underwent PMV during pregnancy in the period 1998-2007. The follow up data of the patients and the born children were obtained from the hospital records and also by contacting the patients via phone. Six patients underwent PMV but follow-up was available for 5 patients only. All 5 patients were admitted due to severe mitral stenosis with symptoms of dyspnea and palpitation. Mean age was 27 +/- 5.3 years with a mean gestational age at the time of procedure of 22.20 +/- 1.6 weeks. The mean valve area increased from 0.94 +/- 0.22 cm2 preoperatively to 1.62 +/- 0.50 cm2 post-operatively. The ejection fraction changed from a mean of 50 +/- 11.7% to 56 +/- 2.2%. There were no maternal deaths, abortions or stillbirths. Developmental milestones were achieved at the appropriate ages in all babies. PMV appears to be a safe and effective intervention for patients with severe MS during pregnancy. Keywords: Mitral stenosis, Percutaneous Mitra

Design and Simulation of Cascaded Class-A Microwave Power Amplifier

Microwave power amplifiers are the most significant components in wireless communications systems. As the technology continue to progress, the designers are facing new challenges and opportunities. The purpose of this work is to push the limits of efficiency and bandwidth of power amplifiers. The objective of this research is to design and build a prototype two stage Microwave power amplifier operated at 2.4 GHz with a linear region of operation up to our desired output of 0.5 watt or 27 dBm. The transistor used in the first stage is BFP540 while the output power of the first stage is the input of the second stage in which the ATF50189 transistor is used to for amplification. All the simulations and readings are taken by using AWR Microwave Office software. By using the load line Rl and the biasing points are achieved for both stages. The applications of our proposed device include many products in the field of microwave communications. One of the important applications of a Microwave power amplifier is in the output stage of a transmitter where a signal needs amplification before it is transmitted.DOI:http://dx.doi.org/10.11591/ijece.v3i5.364

An advanced Wigner-Ville time-frequency analysis of lamb waves signals based upon AR model for efficient damage inspection

The generation and acquisition of the ultrasonic guided wave in metallic or composite structures to investigate the structural defects are quite straightforward; however, the interpretation and evaluation of the reflected/transmitted signal to extract the useful information is a challenging task. It is primarily due to the dispersion, and multi-modal behavior of the Lamb waves which is dependent on the exciting wave frequency and thickness of the material under investigation. These multi-modes and dispersion behavior lead to a complex waveform structure, and therefore, require an advanced signal processing technique to decipher the useful information in time and frequency domain. For this purpose, Wigner-Ville Distribution, due to its desirable mathematical properties, is considered as a powerful tool for estimating temporal and spectral features of this type of complex signals. However, because of its quadratic nature, the undesirable cross-terms and spurious energies are also generated, which limit the readability of the spectrum. To suppress this effect, the autoregressive model based upon Burg's Maximum Entropy method was employed that modified the kernels of the discrete Wigner-Ville Distribution. This technique was applied to ultrasonic Lamb wave signals, obtained numerically and experimentally, to extract useful discriminating spectral and temporal information that was required for mode identification, damage localization, and its quantification. For damage localization, based upon excellent time-frequency energy distribution, the proposed method precisely estimated the distance between two closely spaced notches in a plate from different simulated noisy signals with a maximum uncertainty of 5%. Moreover, time-frequency energy concentration in a combination with variation of its instantaneous frequency was also effective in identifying the overlapping modes of the Lamb wave signal. Lastly, for damage quantification, three time-frequency based damage indices namely, energy concentration, time-frequency flux, and instantaneous frequency were extracted from the five sets of specimens using the proposed time-frequency scheme and trained them for the regression model. The model testing proved that the damage indices has the potential to predict the crack sizes precisely and reliably

WHEAT PHASIC DEVELOPMENT UNDER DIFFERENT SOWING WINDOWS UNDER RAINFED CLIMATE

In rainfed areas of Pakistan, erratic rainfall causes variation in sowing window of wheat starting from mid of October and extends until the end of December. The development of wheat plant is a continuity of vegetative phase, reproductive phase and the grain-filling phase. So, to determine the changes in timing of developmental events during the crop-growing season Wheat cultivar, Wafaq-2001, was planted in four sowing windows (22 October, 13 November, 4 December and 24 December) in the field area of National Agricultural Research Centre (NARC), Islamabad. Observations of crop phenology began at the emergence of first leaf and continued until the maturity when yield data was measured. The study revealed that environmental factors play an important role in determining the duration of each phase in the given agro-ecological conditions. The duration of these phases is strongly influenced by the changes in sowing dates. The major components of the environment that affect development are temperature and photoperiod. There are association between sowing window and the yield and also between the duration of phases and yield. So, it becomes important to be able to manipulate the duration of these phases to customize cultivars for specific environments and get the potential yield in a given environment on sustainable basis. Keywords: Wheat, phasic development,phenology, sowing window

Analysis of the Surface Quality and Temperature in Grinding of Acrylic-Based Resin

Polymeric resins are becoming increasingly popular in medical and engineering applications due to their properties, such as their low weight, high strength, corrosion resistance, non-allergenicity, and extended service life. The grinding process is used to convert these materials into desired products, offering high accuracy and surface quality. However, grinding generates significant heat, which can potentially degrade the material. This study investigates the grinding of acrylic-based resins, specifically focusing on the interplay between the grind zone temperature and surface finish. The low glass transition temperature (57 °C) of the acrylic necessitates the precise control of the grinding parameters (spindle speed, feed rate, depth of cut, and grinding wheel grain size), to maintain a low temperature and achieve high-quality machining. Thermal imaging and thermocouples were employed to measure the grind zone temperature under various grinding conditions. This study investigates the influence of four parameters: spindle speed, feed rate, depth of cut, and grinding wheel grain size. The best surface finish (Ra: 2.5 µm) was obtained by using a finer-grained (80/Ø 0.18 mm) grinding wheel, combined with slightly adjusted parameters (spindle speed: 11.57 m/s, feed rate: 0.406 mm/rev, depth of cut: 1.00 mm), albeit with a slightly higher grind zone temperature (~54 °C). This study highlighted the importance of balancing the grind zone temperature and surface finish for the optimal grinding of acrylic-based resins. Further, this research finds that by carefully controlling the grinding parameters, it is possible to achieve both a high surface quality and prevent material degradation. The research findings could be highly valuable for optimizing the grinding process for various medical and engineering applications

Riba Free Loan in Islamic Finance: Key to Social Development and Welfare

Worldwide Islamic financial institutions (IFIs) do not offer loan for avoiding interest/usury, confine their Shariah interpretations to a particular school of thought and offer products for rich people only. Loans are however demanded by the underdeveloped social actors in economy for welfare and development. As per Islam usury (Riba) free loan (Qard – e – Hassan or Dain) is a key to social development. Modern implicit and explicit shapes of master-servant relation among individuals and institutions are legal phenomena with diversified standards and patterns. As per Jaferia school of thought, Islam allows presetting Hadya (gift) in loans among master-servant. These options were utilized by our study for proposing a Pro-Hadya Riba Free Loan among master-servant. Such model of loaning can help stakeholders of Islamic finance improving the existing landscape from pro-commercial creed to pro - social development approach. It is further a potential replacement of fixed rate of interest/usury with Hadya. Such loan can be utilized for turning pension, gratuity, provident fund and other investment schemes Shariah based easily by taking advantage of master-servant setup. Findings and recommendations of this study contributes novel and further invites future research on its engineered model of loaning

Consumer Attitude towards Counterfeit Products: With Reference to Pakistani Consumers

The main purpose of this research is to develop and test a model that shows the main predictors of consumer’s attitude toward counterfeit products and to help companies to realize the main factors that are influencing consumer attitude towards counterfeit products and build successful anti-piracy policy. Population was all the students of the Bahawalpur District. Sample unit was the students of Islamia University of Bahawalpur as regular or private students. Sample frame was all the students of DMS which are at the level of Bachelor, Master and MS. We have used the convenience and non-probability sampling techniques in this study.  Sample size140 for this study conducted in Bahawalpur district. The main part of the paper is to show that consumer buy counterfeited products are dependent on the attitudes they have toward counterfeit products, which is influenced by price-quality inference, perceived risk, subjective norm, integrity, and personal gratification