The AMADEUS collaboration aims to provide new experimental constraints to the \(K^{-}\)N strong i... more The AMADEUS collaboration aims to provide new experimental constraints to the \(K^{-}\)N strong interaction in the regime of non-perturbative QCD, exploiting low-energy \(K^{-}\) hadronic interactions with light nuclei (e.g. H, \({}^{4}\)He, \({}^{9}\)Be and \({}^{12}\)C). The low-momentum kaons (\(p_{K}\) \(\sim \) 127 MeV/c) produced at the DA\(\Phi \)NE collider are ideal to explore both stopped and in-flight \(K^{-}\) nuclear captures. The KLOE detector is used as an active target, allowing to achieve excellent acceptance and resolutions for the data. In this work the results obtained from the study of \(\varLambda \pi ^{-}\) and \(\varLambda p\) correlated production in the final state are presented.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
This work deals with the first characterization results of an X-ray detection module developed wi... more This work deals with the first characterization results of an X-ray detection module developed within the scope of SIDDHARTA experiment. SIDDHARTA is a nuclear physics experiment aimed at the study of strong nuclear interactions using exotic atoms. This is achieved using monolithic arrays of Silicon Drift Detectors (SDDs), each consisting of eight SDD elements arranged in a 2×4 format (total area 18×34 mm2). A total of 48 SDD arrays arranged on a gantry structure are required to perform the experiment. Each SDD element is coupled to a CUBE pre-amplifier with the consequent shaping amplifier and complementary analog electronic stages implemented in a custom developed 16-channel SFERA chip. During the experiment, SDD arrays must be cooled down to cryogenic temperature below 120 K to perform X-ray spectroscopy to assess spread/shift of energy levels of exotic kaonic atoms. Alongside the cryogenic operation, the X-ray spectrometer needs to operate with a linearity of around 1 ± with an output stability of a few eV/day. This work describes the preliminary characterization results of cryogenically cooled 2×4 SDD arrays readout by SFERA chip. These include X-ray spectroscopy, stability and linearity performances.
2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2017
The design of the detection system for nondestructive analysis of MOX pellets by the accurate mea... more The design of the detection system for nondestructive analysis of MOX pellets by the accurate measurement of the Pu/U ratio in trace concentrations (few %) by means of XRF spectrometry is presented. The parameters of multiple Peltier-cooled compact CdTe detectors are optimized through systematic experimental characterization, leading to a FWHM resolution better than 1 keV at 122 keV $(3.2 \mu \mathrm{s}$ shaping time) stable for days of operation. Given the small separation between the peaks to be quantified (~9 keV) and the low concentration of Pu, accurate spectrum analysis is mandatory. Acquired spectra are processed by an algorithm that subtracts the background and fits the peaks with a combination of Gaussian and exponential tail functions, required to model the slow collection of holes in these detectors. The lack of calibrated Pu/U samples has been addressed by realizing mixtures of Bi/Pb powders (with similar spectral separation) and by creating a virtual spectrum by measuri...
AbstractThis paper presents a brief account of the recent excavation conducted on the site of Bad... more AbstractThis paper presents a brief account of the recent excavation conducted on the site of Badalpur, Taxila Valley in the premises of Haripur District, Khyber Pakhtunkhwa, Pakistan. It focuses on the season 2013 excavations.Introduction:Taxila Valley lies north Latitude 33° 42' 30" and 33' 50° and east longitudes 72° 53' 45' and 72° 59'. The valley derives its name from the historic city of Takshasila or Taxila. The present spelling Taxila was the abbreviated form used by Greeks and Romans and since then commonly adopted by European writers (Khan et al 2007:39). Ancient Takshasila is one of the most important points of cultural diffusion. The innumerable ancient remains, scattered all over the area, is testimony to its greatness.The earliest known settlement of the Taxila Valley is Sarai-Khola which yielded a cultural sequence from late Neolithic to Iron Age i.e. Neolithic period (4000 to 2800 BC), Early Bronze Age Culture (28002600 BC), and the Late Bron...
In the scientific environment, the leading variables such as voltage, current, power, heat from c... more In the scientific environment, the leading variables such as voltage, current, power, heat from cooling system, membrane temperature and hydrogen pressure are uses as steady state and transient behaviors of Fuel Cells (FC). In the reproducing process of Fuel Cells (FC) variations, DC-DC converters are connected transversely its terminals, the efficiency, stability and durability are considered as operational problems for steady state. Since the Proton Exchange Fuel Cell is a non-linear process and its parameters change when it is delivering energy to the grid. The conventional controllers can’t content the control objectives. In this paper, an intelligent DC-AC power optimization is proposed for Fuel Cell (FC) control system to produce energy in the grid stations and to improve the power quality when FC is supplying load to grid. Furthermore, a Genetic Algorithm (GA) based reactive power optimization for voltage profile improvement and real power minimization in DC-AC system. A fuzz...
This case examines the June 2015 decision of Muhammad Asad, a fund manager at Al Meezan Investmen... more This case examines the June 2015 decision of Muhammad Asad, a fund manager at Al Meezan Investment Management Limited, to participate in the Initial Public Offering (IPO) of Al Shaheer Corporation, a leading meat sector company of Pakistan. He was interested in increasing the exposure of the Meezan Islamic Fund (MIF) to the food sector, provided attractive risk-adjusted returns could be achieved. Based on the research team analysis and his own assessment, Asad had to decide whether or not to participate in the IPO book building process and the number of shares to bid for at each price level. Both Market Multiples and Discounted Cash Flow (DCF) valuation methods had yielded share value higher than the IPO floor price of PKR 43 per share which encouraged Asad to consider the investment opportunity. He also had to decide on the amount that he could allocate to the IPO on behalf of MIF. Asad had to prepare his recommendations on the IPO for presentation and approval by the investment co...
Endocrinology, Diabetes & Metabolism Case Reports, 2019
Summary We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took lon... more Summary We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took longer than we anticipated to treat despite initiation of our DKA protocol. Both patients had an unequivocal diagnosis of type 2 diabetes, had poor glycaemic control with a history of metformin intolerance and presented with relatively vague symptoms post-operatively. Neither patient had stopped their SGLT2i pre-operatively, but ought to have by current treatment guidelines. Learning points: SGLT2i-induced EDKA is a more protracted and prolonged metabolic derangement and takes approximately twice as long to treat as hyperglycaemic ketoacidosis. Surgical patients ought to stop SGLT2i medications routinely pre-operatively and only resume them after they have made a full recovery from the operation. While the mechanistic basis for EDKA remains unclear, our observation of marked ketonuria in both patients suggests that impaired ketone excretion may not be the predominant metabolic lesion in eve...
2015 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2015
Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPMs) are two silicon based photo-d... more Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPMs) are two silicon based photo-detector technologies for scintillator readout with applications in medical imaging, nuclear physics, space research and others. These devices provide compact scintillator readout solutions for spectroscopy, imaging and timing measurements. Goal of this work, is to make a comparison between these two photo-detector technologies, in particular for gamma-ray spectroscopy measurements. SDDs are characterized by very high quantum efficiency (> 80%) with no multiplication which helps to keep the statistical contribution to the energy resolution close to Poisson limit but, at the same time, makes the system very sensitive to readout electronics noise. SiPM devices on the other hand, have a very high multiplication gain (105-106) which makes the electronics noise contribution almost negligible, with only the dark count rate contribution which can be reduced with moderate cooling. However, they are characterized by lower Photo Detection Efficiency (PDE) ~30-40% and statistical spread of the multiplication gain. In order to compare the spectroscopy performances of the two photo-detectors, we evaluate the energy resolution achievable with them using a large Lanthanum Bromide scintillator. Expected energy resolution with 1" LaBr3:Ce and its sensitivity to various parameters of SDDs and SiPMs are evaluated to analyze the photo-detector performances. With SDD arrays of 2 nA/cm2 leakage current technology, an energy resolution of 3.0% has already been measured at -20 °C with Cs-137 source at a shaper peaking time of 6 μs. In this work, we measure an energy resolution of 4.9% with a SiPM tile readout by an RC filter (300 ns time constant) and a temperature of around 36 °C. These results are then used to validate the theoretical energy resolution estimates and to generalize the comparison of these two readout technologies.
The study investigates the influence of demographics (residential area, age, gender, marital stat... more The study investigates the influence of demographics (residential area, age, gender, marital status, education background) and personality traits (extraversion, openness, conscientiousness, neuroticism, and agreeableness) on the financial behavioral biases (overconfidence, herding/mass behavior and disposition effect) and risk taking behavior in Pakistan. The study will be beneficial for the financial advisors and individual investors. As it will help financial advisor to know potential behavioral biases in each type of investors while making investment decision and therefore they can advise investors properly to mitigate such biases. Personality dimensions are categorized under Big Five Personality model. Questionnaire survey method is used to collect the data from a Sample size of 225 respondents that includes bankers, finance students as well as investors. Structure equation modeling (SEM) analysis is used to analyze the impact of personality traits and demographics on the investment biases through Amos 20. The results show that big five personality traits have a significant relationship with overconfidence, herding/mass behavior and risk taking except disposition effect.
This work describes the development of a gamma detector based on silicon drift detectors (SDDs) t... more This work describes the development of a gamma detector based on silicon drift detectors (SDDs) to read out large LaBr3: Ce scintillators for gamma-ray astronomy applications, within an activity supported by the European Space Agency (ESA). SDDs, characterized by high quantum efficiency and low electronic noise, when coupled with a scintillator are good candidates for gamma-ray spectroscopy applications in a wide energy range, e.g., from 150 keV to 15 MeV. The gamma-ray detector prototype presented here is composed of a 2 '' ×2 '' LaBr3: Ce scintillator coupled with four SDD arrays arranged in a 2 ×2 format (a total of 36 SDDs). This detection system is operated with custom readout application specific integrated circuits (ASICs) and a data acquisition (DAQ) system. With this prototype gamma-camera, an energy resolution of 3.4% FWHM at 662 keV has been measured. Spectroscopy measurements have been carried out between 300 keV and 1800 keV and the achieved results are consistent with the electronic noise of the SDD technology. In this work, we report on the SDD based detection head's design, its X-ray characterization, readout electronics, experimental setups and gamma-ray spectroscopy results. Finally, perspectives with the possible use of an improved SDD technology are discussed.
ABSTRACT This work deals with the development of Silicon Drift Detectors (SDDs) of different size... more ABSTRACT This work deals with the development of Silicon Drift Detectors (SDDs) of different sizes and low noise CMOS read-out preamplifiers in view of their use in nuclear physics experiments, like the SIDDHARTA upgrade supported by Italian INFN. In this work we report about the recent SDDs and CMOS preamplifiers development, with particular emphasis on X-ray measurements at cryogenic temperatures. The SDDs presented are designed as single square shaped units of different areas 64 mm2 (8mm × 8mm) or 144 mm2 (12mm × 12mm) and also as monolithic arrays of 9 elements (8mm × 8mm each, total area 26mm × 26mm) in a3 × 3 format. The detectors have been designed and manufactured by the Fondazione Bruno Kessler (FBK). The read-out of the SDDs is based on the CMOS preamplifier (CUBE) for both the single unit and the 3 × 3 array. The CMOS technology is intrinsically more robust at lower temperatures with respect to the more conventional JFET transistor used in SDDs readout. A measured resolution of 123 eV on the Mn-Kα line with the optimum shaping time and a resolution of 126.4 eV with 250 ns shaping time have been obtained with round shaped 10 mm2 SDDs detectors. This last result leads to excellent spectroscopy performances even with very high input count rates making the SDD+CUBE combination very attractive also for synchrotron applications. The nine detectors array in addition to the preamplifiers the use of a multichannel ASIC for signal shaping and peak detection of all the units and of a custom Data Acquisition System. Also preliminary measurements of low energies lines are reported in order to prove the possibility of soft X-ray detection.
The present paper is aimed at analyzing the impact of dividend policy of shareholders’ wealth in ... more The present paper is aimed at analyzing the impact of dividend policy of shareholders’ wealth in Textile sector of Pakistan during 2004 to onwards. To measure the impact of dividend policy on shareholders’ wealth multiple regression method and stepwise regression models will be used by taking (Dividend per Share), RE it (Retained Earnings per Share), Pet-1 (Lagged Price Earning Ratio) and MPSit-1 (Lagged Market Price) (MVit-1) as independent variable, and MPSit (Market Price per Share) as dependent variables. To determine the proportion of explained variation in the dependent variable, the co-efficient of determination (R2) will be tested with the help of F value. The previous study done in this field study proved that the wealth of the shareholders is greatly influenced mainly by five variables viz., Growth in sales, Improvement of Profit Margin, Capital Investment Decisions (both working capital and fixed capital), Capital Structure Decisions, Cost of Capital (Dividend on Equity, Interest on Debt) etc. The previous study was done on organic and inorganic chemical industries of India. The author found a significant impact of dividend policy on shareholders’ wealth in Organic Chemical Companies while the shareholders’ wealth is not influenced by dividend payout as far as Inorganic Chemical Companies are concerned. This study aims to apply the previous research on textile sector of Pakistan.
This work deals with the development and testing of a low latency Animation Transmission Technolo... more This work deals with the development and testing of a low latency Animation Transmission Technology (ATT) for augmented reality applications. This web-based transmission system based on AutoBahn Pyhton web server and WebSocket LibrarY (WSLAY) integrated clients has been studied to reduce packet header size and to simultaneously allow a large number of Users to interact with each other. The transmission system in the proposed system architecture allows motion sensor’s acquisition software to easily send compressed 3D quaternion-based data from transmitter to the rendering softwares at receiver side to generate real time 3D animation on an avatar. Furthermore, effects of lossy compression of quaternion data and server limitation have also been considered. Initial simulation test results with the Python server alongside WSLAY integrated clients with virtual motion sensors have been presented in this work. It has been evaluated that the network delay (ND) has a huge improvement from mor...
This work describes the energy requirements for water supply and sewerage management of Faisalaba... more This work describes the energy requirements for water supply and sewerage management of Faisalabad urban area and additionally suggests energy management improvements by incorporating grid connected renewable Photo-Voltaic (PV) based power generation. As the ground water in Faisalabad is mostly saline, Water and Sanitation Agency Faisalabad (WASA FSD) brings water from nearby soft water sources and pumps them to consumers within the city. To maintain water supply and sewerage disposal operations, WASA FSD requires to purchase 40k to 50k USD worth of electricity monthly from Faisalabad Electric Supply Company (FESCO) which is financially burdening for WASA. Additionally, as this energy demand is met from Pakistan's already strained national grid, there is a need to better manage Agency's energy requirements. In this work, we study utilization of an On-Grid PV solution for renewable power generation to meet the agency's requirement of are 3.238 ×10 6 electricity units per month. Such systems can, in principle, eliminate dependency of WASA on the National Grid and additionally provide WASA with an energy efficient and sustainable power generation system with low environmental impact. In this paper, simulate a solar energy system without any energy storage system to determine its feasibility. Here, we present simulation results to estimate successfulness of such a project. Additionally, financial and technical aspects of the project have also been discussed suggesting a payback period less than 7 years.
Biomedical telemetry relies heavily on implantable antennas. Due to this, we have designed and te... more Biomedical telemetry relies heavily on implantable antennas. Due to this, we have designed and tested a compact, a circularly polarized, a low-profile biomedical implantable antenna that operate in the 2.45 GHz ISM band. In order to keep the antenna compact, modified co-planar waveguide (CPW) technology is used. Slotted rectangular patch with one 45-degree angle slot and truncated little patch on the left end of the ground plane generate a frequency-range antenna with circular polarization. Using a 0.25-millimeter-thick Roger Duroid-RT5880 substrate with a thickness of εr = 2.2, tanδ = 0.0009 provides flexibility. The volume of the antenna is 21 mm x 13.5 mm x 0.254 mm (0.25λg × 0.16λg × 0.003λg). The antenna covers 2.35–2.55 GHz (200 MHz) in free space and 1.63–1.17 GHz (1.17 GHz) in epidermal tissue. With skin tissue that has more bandwidth, the (x and y)-axis bends of the antenna are also simulated via the simulation. Bended antenna simulations and measurements show excellent agr...
The Applied Computational Electromagnetics Society Journal (ACES)
In this paper, a novel planar Butler matrix (BM) utilizing only 3dB3dBhybrid couplers and a cros... more In this paper, a novel planar Butler matrix (BM) utilizing only 3dB3dBhybrid couplers and a crossover are implemented using a low-cost silver-nano inkjet printing technique. Unlike in the conventional design of BM where a phase shifter is required, this novel design does not need a phase shifter to be implemented. However, the use of delicate substrates like polyethylene terephthalate (PET) in the design makes it unique. This is not possible with the conventional thermal curing process, as PET substrate cannot be subjected to an excessively feverish temperature. The results obtained show good return loss and transmission coefficients better than 26.1026.10 and 23.54dB23.54dB, respectively, at the center frequency. Similarly, an amplitude imbalance of less than 2.4dB2.4dB with phase mismatch within ±0.25∘±0.25∘ is achieved at the center frequency. The BM has a −10dB-10dB bandwidth of 24.79% with a beam pattern produced at +13∘+13∘,−40∘-40∘, +40∘+40∘, and −13∘-13∘ when ports 1-4 o...
The AMADEUS collaboration aims to provide new experimental constraints to the \(K^{-}\)N strong i... more The AMADEUS collaboration aims to provide new experimental constraints to the \(K^{-}\)N strong interaction in the regime of non-perturbative QCD, exploiting low-energy \(K^{-}\) hadronic interactions with light nuclei (e.g. H, \({}^{4}\)He, \({}^{9}\)Be and \({}^{12}\)C). The low-momentum kaons (\(p_{K}\) \(\sim \) 127 MeV/c) produced at the DA\(\Phi \)NE collider are ideal to explore both stopped and in-flight \(K^{-}\) nuclear captures. The KLOE detector is used as an active target, allowing to achieve excellent acceptance and resolutions for the data. In this work the results obtained from the study of \(\varLambda \pi ^{-}\) and \(\varLambda p\) correlated production in the final state are presented.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
This work deals with the first characterization results of an X-ray detection module developed wi... more This work deals with the first characterization results of an X-ray detection module developed within the scope of SIDDHARTA experiment. SIDDHARTA is a nuclear physics experiment aimed at the study of strong nuclear interactions using exotic atoms. This is achieved using monolithic arrays of Silicon Drift Detectors (SDDs), each consisting of eight SDD elements arranged in a 2×4 format (total area 18×34 mm2). A total of 48 SDD arrays arranged on a gantry structure are required to perform the experiment. Each SDD element is coupled to a CUBE pre-amplifier with the consequent shaping amplifier and complementary analog electronic stages implemented in a custom developed 16-channel SFERA chip. During the experiment, SDD arrays must be cooled down to cryogenic temperature below 120 K to perform X-ray spectroscopy to assess spread/shift of energy levels of exotic kaonic atoms. Alongside the cryogenic operation, the X-ray spectrometer needs to operate with a linearity of around 1 ± with an output stability of a few eV/day. This work describes the preliminary characterization results of cryogenically cooled 2×4 SDD arrays readout by SFERA chip. These include X-ray spectroscopy, stability and linearity performances.
2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2017
The design of the detection system for nondestructive analysis of MOX pellets by the accurate mea... more The design of the detection system for nondestructive analysis of MOX pellets by the accurate measurement of the Pu/U ratio in trace concentrations (few %) by means of XRF spectrometry is presented. The parameters of multiple Peltier-cooled compact CdTe detectors are optimized through systematic experimental characterization, leading to a FWHM resolution better than 1 keV at 122 keV $(3.2 \mu \mathrm{s}$ shaping time) stable for days of operation. Given the small separation between the peaks to be quantified (~9 keV) and the low concentration of Pu, accurate spectrum analysis is mandatory. Acquired spectra are processed by an algorithm that subtracts the background and fits the peaks with a combination of Gaussian and exponential tail functions, required to model the slow collection of holes in these detectors. The lack of calibrated Pu/U samples has been addressed by realizing mixtures of Bi/Pb powders (with similar spectral separation) and by creating a virtual spectrum by measuri...
AbstractThis paper presents a brief account of the recent excavation conducted on the site of Bad... more AbstractThis paper presents a brief account of the recent excavation conducted on the site of Badalpur, Taxila Valley in the premises of Haripur District, Khyber Pakhtunkhwa, Pakistan. It focuses on the season 2013 excavations.Introduction:Taxila Valley lies north Latitude 33° 42' 30" and 33' 50° and east longitudes 72° 53' 45' and 72° 59'. The valley derives its name from the historic city of Takshasila or Taxila. The present spelling Taxila was the abbreviated form used by Greeks and Romans and since then commonly adopted by European writers (Khan et al 2007:39). Ancient Takshasila is one of the most important points of cultural diffusion. The innumerable ancient remains, scattered all over the area, is testimony to its greatness.The earliest known settlement of the Taxila Valley is Sarai-Khola which yielded a cultural sequence from late Neolithic to Iron Age i.e. Neolithic period (4000 to 2800 BC), Early Bronze Age Culture (28002600 BC), and the Late Bron...
In the scientific environment, the leading variables such as voltage, current, power, heat from c... more In the scientific environment, the leading variables such as voltage, current, power, heat from cooling system, membrane temperature and hydrogen pressure are uses as steady state and transient behaviors of Fuel Cells (FC). In the reproducing process of Fuel Cells (FC) variations, DC-DC converters are connected transversely its terminals, the efficiency, stability and durability are considered as operational problems for steady state. Since the Proton Exchange Fuel Cell is a non-linear process and its parameters change when it is delivering energy to the grid. The conventional controllers can’t content the control objectives. In this paper, an intelligent DC-AC power optimization is proposed for Fuel Cell (FC) control system to produce energy in the grid stations and to improve the power quality when FC is supplying load to grid. Furthermore, a Genetic Algorithm (GA) based reactive power optimization for voltage profile improvement and real power minimization in DC-AC system. A fuzz...
This case examines the June 2015 decision of Muhammad Asad, a fund manager at Al Meezan Investmen... more This case examines the June 2015 decision of Muhammad Asad, a fund manager at Al Meezan Investment Management Limited, to participate in the Initial Public Offering (IPO) of Al Shaheer Corporation, a leading meat sector company of Pakistan. He was interested in increasing the exposure of the Meezan Islamic Fund (MIF) to the food sector, provided attractive risk-adjusted returns could be achieved. Based on the research team analysis and his own assessment, Asad had to decide whether or not to participate in the IPO book building process and the number of shares to bid for at each price level. Both Market Multiples and Discounted Cash Flow (DCF) valuation methods had yielded share value higher than the IPO floor price of PKR 43 per share which encouraged Asad to consider the investment opportunity. He also had to decide on the amount that he could allocate to the IPO on behalf of MIF. Asad had to prepare his recommendations on the IPO for presentation and approval by the investment co...
Endocrinology, Diabetes & Metabolism Case Reports, 2019
Summary We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took lon... more Summary We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took longer than we anticipated to treat despite initiation of our DKA protocol. Both patients had an unequivocal diagnosis of type 2 diabetes, had poor glycaemic control with a history of metformin intolerance and presented with relatively vague symptoms post-operatively. Neither patient had stopped their SGLT2i pre-operatively, but ought to have by current treatment guidelines. Learning points: SGLT2i-induced EDKA is a more protracted and prolonged metabolic derangement and takes approximately twice as long to treat as hyperglycaemic ketoacidosis. Surgical patients ought to stop SGLT2i medications routinely pre-operatively and only resume them after they have made a full recovery from the operation. While the mechanistic basis for EDKA remains unclear, our observation of marked ketonuria in both patients suggests that impaired ketone excretion may not be the predominant metabolic lesion in eve...
2015 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2015
Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPMs) are two silicon based photo-d... more Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPMs) are two silicon based photo-detector technologies for scintillator readout with applications in medical imaging, nuclear physics, space research and others. These devices provide compact scintillator readout solutions for spectroscopy, imaging and timing measurements. Goal of this work, is to make a comparison between these two photo-detector technologies, in particular for gamma-ray spectroscopy measurements. SDDs are characterized by very high quantum efficiency (> 80%) with no multiplication which helps to keep the statistical contribution to the energy resolution close to Poisson limit but, at the same time, makes the system very sensitive to readout electronics noise. SiPM devices on the other hand, have a very high multiplication gain (105-106) which makes the electronics noise contribution almost negligible, with only the dark count rate contribution which can be reduced with moderate cooling. However, they are characterized by lower Photo Detection Efficiency (PDE) ~30-40% and statistical spread of the multiplication gain. In order to compare the spectroscopy performances of the two photo-detectors, we evaluate the energy resolution achievable with them using a large Lanthanum Bromide scintillator. Expected energy resolution with 1" LaBr3:Ce and its sensitivity to various parameters of SDDs and SiPMs are evaluated to analyze the photo-detector performances. With SDD arrays of 2 nA/cm2 leakage current technology, an energy resolution of 3.0% has already been measured at -20 °C with Cs-137 source at a shaper peaking time of 6 μs. In this work, we measure an energy resolution of 4.9% with a SiPM tile readout by an RC filter (300 ns time constant) and a temperature of around 36 °C. These results are then used to validate the theoretical energy resolution estimates and to generalize the comparison of these two readout technologies.
The study investigates the influence of demographics (residential area, age, gender, marital stat... more The study investigates the influence of demographics (residential area, age, gender, marital status, education background) and personality traits (extraversion, openness, conscientiousness, neuroticism, and agreeableness) on the financial behavioral biases (overconfidence, herding/mass behavior and disposition effect) and risk taking behavior in Pakistan. The study will be beneficial for the financial advisors and individual investors. As it will help financial advisor to know potential behavioral biases in each type of investors while making investment decision and therefore they can advise investors properly to mitigate such biases. Personality dimensions are categorized under Big Five Personality model. Questionnaire survey method is used to collect the data from a Sample size of 225 respondents that includes bankers, finance students as well as investors. Structure equation modeling (SEM) analysis is used to analyze the impact of personality traits and demographics on the investment biases through Amos 20. The results show that big five personality traits have a significant relationship with overconfidence, herding/mass behavior and risk taking except disposition effect.
This work describes the development of a gamma detector based on silicon drift detectors (SDDs) t... more This work describes the development of a gamma detector based on silicon drift detectors (SDDs) to read out large LaBr3: Ce scintillators for gamma-ray astronomy applications, within an activity supported by the European Space Agency (ESA). SDDs, characterized by high quantum efficiency and low electronic noise, when coupled with a scintillator are good candidates for gamma-ray spectroscopy applications in a wide energy range, e.g., from 150 keV to 15 MeV. The gamma-ray detector prototype presented here is composed of a 2 '' ×2 '' LaBr3: Ce scintillator coupled with four SDD arrays arranged in a 2 ×2 format (a total of 36 SDDs). This detection system is operated with custom readout application specific integrated circuits (ASICs) and a data acquisition (DAQ) system. With this prototype gamma-camera, an energy resolution of 3.4% FWHM at 662 keV has been measured. Spectroscopy measurements have been carried out between 300 keV and 1800 keV and the achieved results are consistent with the electronic noise of the SDD technology. In this work, we report on the SDD based detection head's design, its X-ray characterization, readout electronics, experimental setups and gamma-ray spectroscopy results. Finally, perspectives with the possible use of an improved SDD technology are discussed.
ABSTRACT This work deals with the development of Silicon Drift Detectors (SDDs) of different size... more ABSTRACT This work deals with the development of Silicon Drift Detectors (SDDs) of different sizes and low noise CMOS read-out preamplifiers in view of their use in nuclear physics experiments, like the SIDDHARTA upgrade supported by Italian INFN. In this work we report about the recent SDDs and CMOS preamplifiers development, with particular emphasis on X-ray measurements at cryogenic temperatures. The SDDs presented are designed as single square shaped units of different areas 64 mm2 (8mm × 8mm) or 144 mm2 (12mm × 12mm) and also as monolithic arrays of 9 elements (8mm × 8mm each, total area 26mm × 26mm) in a3 × 3 format. The detectors have been designed and manufactured by the Fondazione Bruno Kessler (FBK). The read-out of the SDDs is based on the CMOS preamplifier (CUBE) for both the single unit and the 3 × 3 array. The CMOS technology is intrinsically more robust at lower temperatures with respect to the more conventional JFET transistor used in SDDs readout. A measured resolution of 123 eV on the Mn-Kα line with the optimum shaping time and a resolution of 126.4 eV with 250 ns shaping time have been obtained with round shaped 10 mm2 SDDs detectors. This last result leads to excellent spectroscopy performances even with very high input count rates making the SDD+CUBE combination very attractive also for synchrotron applications. The nine detectors array in addition to the preamplifiers the use of a multichannel ASIC for signal shaping and peak detection of all the units and of a custom Data Acquisition System. Also preliminary measurements of low energies lines are reported in order to prove the possibility of soft X-ray detection.
The present paper is aimed at analyzing the impact of dividend policy of shareholders’ wealth in ... more The present paper is aimed at analyzing the impact of dividend policy of shareholders’ wealth in Textile sector of Pakistan during 2004 to onwards. To measure the impact of dividend policy on shareholders’ wealth multiple regression method and stepwise regression models will be used by taking (Dividend per Share), RE it (Retained Earnings per Share), Pet-1 (Lagged Price Earning Ratio) and MPSit-1 (Lagged Market Price) (MVit-1) as independent variable, and MPSit (Market Price per Share) as dependent variables. To determine the proportion of explained variation in the dependent variable, the co-efficient of determination (R2) will be tested with the help of F value. The previous study done in this field study proved that the wealth of the shareholders is greatly influenced mainly by five variables viz., Growth in sales, Improvement of Profit Margin, Capital Investment Decisions (both working capital and fixed capital), Capital Structure Decisions, Cost of Capital (Dividend on Equity, Interest on Debt) etc. The previous study was done on organic and inorganic chemical industries of India. The author found a significant impact of dividend policy on shareholders’ wealth in Organic Chemical Companies while the shareholders’ wealth is not influenced by dividend payout as far as Inorganic Chemical Companies are concerned. This study aims to apply the previous research on textile sector of Pakistan.
This work deals with the development and testing of a low latency Animation Transmission Technolo... more This work deals with the development and testing of a low latency Animation Transmission Technology (ATT) for augmented reality applications. This web-based transmission system based on AutoBahn Pyhton web server and WebSocket LibrarY (WSLAY) integrated clients has been studied to reduce packet header size and to simultaneously allow a large number of Users to interact with each other. The transmission system in the proposed system architecture allows motion sensor’s acquisition software to easily send compressed 3D quaternion-based data from transmitter to the rendering softwares at receiver side to generate real time 3D animation on an avatar. Furthermore, effects of lossy compression of quaternion data and server limitation have also been considered. Initial simulation test results with the Python server alongside WSLAY integrated clients with virtual motion sensors have been presented in this work. It has been evaluated that the network delay (ND) has a huge improvement from mor...
This work describes the energy requirements for water supply and sewerage management of Faisalaba... more This work describes the energy requirements for water supply and sewerage management of Faisalabad urban area and additionally suggests energy management improvements by incorporating grid connected renewable Photo-Voltaic (PV) based power generation. As the ground water in Faisalabad is mostly saline, Water and Sanitation Agency Faisalabad (WASA FSD) brings water from nearby soft water sources and pumps them to consumers within the city. To maintain water supply and sewerage disposal operations, WASA FSD requires to purchase 40k to 50k USD worth of electricity monthly from Faisalabad Electric Supply Company (FESCO) which is financially burdening for WASA. Additionally, as this energy demand is met from Pakistan's already strained national grid, there is a need to better manage Agency's energy requirements. In this work, we study utilization of an On-Grid PV solution for renewable power generation to meet the agency's requirement of are 3.238 ×10 6 electricity units per month. Such systems can, in principle, eliminate dependency of WASA on the National Grid and additionally provide WASA with an energy efficient and sustainable power generation system with low environmental impact. In this paper, simulate a solar energy system without any energy storage system to determine its feasibility. Here, we present simulation results to estimate successfulness of such a project. Additionally, financial and technical aspects of the project have also been discussed suggesting a payback period less than 7 years.
Biomedical telemetry relies heavily on implantable antennas. Due to this, we have designed and te... more Biomedical telemetry relies heavily on implantable antennas. Due to this, we have designed and tested a compact, a circularly polarized, a low-profile biomedical implantable antenna that operate in the 2.45 GHz ISM band. In order to keep the antenna compact, modified co-planar waveguide (CPW) technology is used. Slotted rectangular patch with one 45-degree angle slot and truncated little patch on the left end of the ground plane generate a frequency-range antenna with circular polarization. Using a 0.25-millimeter-thick Roger Duroid-RT5880 substrate with a thickness of εr = 2.2, tanδ = 0.0009 provides flexibility. The volume of the antenna is 21 mm x 13.5 mm x 0.254 mm (0.25λg × 0.16λg × 0.003λg). The antenna covers 2.35–2.55 GHz (200 MHz) in free space and 1.63–1.17 GHz (1.17 GHz) in epidermal tissue. With skin tissue that has more bandwidth, the (x and y)-axis bends of the antenna are also simulated via the simulation. Bended antenna simulations and measurements show excellent agr...
The Applied Computational Electromagnetics Society Journal (ACES)
In this paper, a novel planar Butler matrix (BM) utilizing only 3dB3dBhybrid couplers and a cros... more In this paper, a novel planar Butler matrix (BM) utilizing only 3dB3dBhybrid couplers and a crossover are implemented using a low-cost silver-nano inkjet printing technique. Unlike in the conventional design of BM where a phase shifter is required, this novel design does not need a phase shifter to be implemented. However, the use of delicate substrates like polyethylene terephthalate (PET) in the design makes it unique. This is not possible with the conventional thermal curing process, as PET substrate cannot be subjected to an excessively feverish temperature. The results obtained show good return loss and transmission coefficients better than 26.1026.10 and 23.54dB23.54dB, respectively, at the center frequency. Similarly, an amplitude imbalance of less than 2.4dB2.4dB with phase mismatch within ±0.25∘±0.25∘ is achieved at the center frequency. The BM has a −10dB-10dB bandwidth of 24.79% with a beam pattern produced at +13∘+13∘,−40∘-40∘, +40∘+40∘, and −13∘-13∘ when ports 1-4 o...
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Papers by Arslan Butt