For immense demand of speedy high-end gadgets, chips are becoming denser, but Moore's law is ... more For immense demand of speedy high-end gadgets, chips are becoming denser, but Moore's law is falling flat lately. Complementary Metal-Oxide-Semiconductor (CMOS) technology is on its brink. Quantum-dot cellular automata (QCA) has become a potential alternative technology to provide faster speed with low power dissipation at nano-scale extent. Here, we proposed an efficient QCA design of 1-bit comparator. The proposed comparator required 59% less area and dissipated 82% less energy. QCA Designer has been used to design and simulate the proposed comparator. Finally, QCAPro tool has been employed for estimating energy dissipation. Özet. Hızlı üst düzey cihazların büyük talepleri için çipler yoğunlaşmakta ancak Moore yasası son zamanlarda düşmektedir. Tamamlayıcı Metal-Oksit-Yarı iletken (CMOS) teknolojisi eşiğe ulaşmıştır. Kuantum noktalı hücresel otomasyon (QCA), nano ölçekte düşük güç dağılımıyla daha hızlı bir hız sağlamak için potansiyel bir alternatif teknoloji haline gelmiştir...
— Quantum dot Cellular Automata (QCA) is anticipated to allow for extremely dense nano-scale desi... more — Quantum dot Cellular Automata (QCA) is anticipated to allow for extremely dense nano-scale design and implementation of logic circuit over the Complementary Metal Oxide Semiconductor (CMOS). QCA has been considered as a promising alternative to CMOS technology for its lower power consumption, higher scale integration and higher switching frequency. Moreover, the basic element in QCA is majority gate. This paper present Double Feynman Gate (F2G) based on QCA logic gates: the QCA wire, MV gate and Inverter gate. The proposed circuit is designed and verified using QCADesigner. Keywords- QCA, QCA Logic Gates, Double Feynman Gate (F2G), MV, Inverter gate I.
2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE)
Diabetes Mellitus (DM) or diabetes is one of the metabolic diseases exhibiting high blood glucose... more Diabetes Mellitus (DM) or diabetes is one of the metabolic diseases exhibiting high blood glucose level over a prolonged period. The management of diabetes is associated with the proper monitoring of blood glucose level. Researchers have been working on developing robust techniques to monitor the level of glucose in the blood. This paper aims at predicting blood glucose levels based on NIR spectroscopic response data utilizing machine learning techniques. Blood glucose samples were prepared in a controlled environment and the NIR spectrums of the samples were obtained using NeoSpectraMicro development kit. Two machine learning approaches have been employed to analyze the experimental dataset. Firstly, the Random Forest Algorithm (RF) followed by Support Vector Machine (SVM) has been utilized that provides an accuracy of 67.5%. Then, a combination of Principle Component Analysis (PCA) and SVM is used. PCA followed by SVM shows a promising result of 77.5% accuracy compared to the previous technique. The numerical findings reveal that the NIR spectroscopy with appropriate data modeling algorithm can be a potential candidate for non-invasive blood glucose monitoring system.
Quantum Dot Cellular Automata (QCA) is a promising nanotechnology in Quantum electronics for its ... more Quantum Dot Cellular Automata (QCA) is a promising nanotechnology in Quantum electronics for its ultra low power consumption, faster speed and small size features . It has significant advantages over the Complementary Metal–Oxide–Semiconductor (CMOS) technology. This paper present , a novel QCA representation of Six-Correction Logic (SCL) gate based on QCA logic gates: the Maj 3 , Maj AND gate and Maj OR. In order to design and verify the functionality of the proposed layout, QCADesigner a familiar QCA simulator has been employed. The simulation results confirm correctness of the claims and its usefulness in designing a digital circuits.
Abstract A numerical simulation and substantiation have been accomplished to analyze the impact o... more Abstract A numerical simulation and substantiation have been accomplished to analyze the impact of Al0.9Ga0.1As alloy composite buffer layer band gap and thickness, absorber layer thickness on a ZnO:Al/i-ZnO/Al0.9Ga0.1As/CIGS/Mo/SLG structured non-toxic Cd-free CIGS photovoltaic cell. In this study, the cell output attributes including efficiency (η) and collection efficiency (ηc) have been optimized through short circuit current density (Jsc), open-circuit voltage (Voc) and fill factor (FF) optimization. Our study has been concluded with the maximum efficiency of 24.32% with Voc = 839.76 mV, Jsc = 36.21mA/cm2 and FF=76.96%, ηc = 83.16%. This enhanced efficiency is optimized by determining the bandgap of the buffer through altering the Al concentration to transit it from direct bandgap material to an indirect one. The thickness of the absorber on system performance is also investigated, and its extent is found in between 2 µm to 3 µm.
A crop’s health can be determined by its leaf nutrient status; more precisely, leaf nitrogen (N) ... more A crop’s health can be determined by its leaf nutrient status; more precisely, leaf nitrogen (N) level, is a critical indicator that carries a lot of worthwhile nutrient information for classifying the plant’s health. However, the existing non-invasive techniques are expensive and bulky. The aim of this study is to develop a low-cost, quick-read multi-spectral sensor array to predict N level in leaves non-invasively. The proposed sensor module has been developed using two reflectance-based multi-spectral sensors (visible and near-infrared (NIR)). In addition, the proposed device can capture the reflectance data at 12 different wavelengths (six for each sensor). We conducted the experiment on canola leaves in a controlled greenhouse environment as well as in the field. In the greenhouse experiment, spectral data were collected from 87 leaves of 24 canola plants, subjected to varying levels of N fertilization. Later, 42 canola cultivars were subjected to low and high nitrogen levels i...
IEEE Transactions on Very Large Scale Integration (VLSI) Systems
Quantum-dot cellular automata (QCA) is recognized as one of the rapidly growing nanotechnologies ... more Quantum-dot cellular automata (QCA) is recognized as one of the rapidly growing nanotechnologies and an alternate to CMOS at the nanoscale. The QCA technology is capable of designing nanoscale digital circuits with a clock speed of terahertz range and ultralow power consumption. In this article, an effective single-layer binary discrete cosine transform (BinDCT) has been reported. To realize the BinDCT architecture in QCA, we also proposed several associated combinational and sequential logic elements of low complexity. All reported circuit layouts were designed and verified using the QCADesigner tool. Moreover, QCAPro is used to estimate the energy dissipation. All comparative study indicates that the reported designs are superior to previous designs in terms of cell complexity, covered area, and energy dissipation. In particular, the proposed QCA BinDCT achieved 39% cell count and 20% covered area improvements compared with the previous QCA BinDCT architecture. Moreover, in terms of power dissipation, the proposed QCA BinDCT dissipates $1.394 \times 10^{-4}$ mW, whereas CMOS- and QCA-based BinDCT architectures consume 0.195 and 0.091 mW of power, respectively.
Quantum-dot cellular automata (QCA) is a rapidly growing nanotechnology very well suited for desi... more Quantum-dot cellular automata (QCA) is a rapidly growing nanotechnology very well suited for designing ultra-dense, low-power, and high-performance digital circuits. In parallel computing, the multistage interconnection network (MIN) provides maximum bandwidth to the components and minimum latency access to the memory modules. Much research has been conducted on CMOS-based MINs for parallel computing. However, the QCA-based switching network is still underexplored. This article proposes a QCA architecture of a new single-layer butterfly switching network (BSN). To achieve this, we design an efficient 2 × 2 switching element (SE), using a modified majority ($\mathcal{M}{_{[x,y]}}$) gate that is fully utilized (i.e., no fixed logic like “0” and “1” at the inputs). The use of a fully utilized majority gate over a partially utilized majority (PUM) one makes the proposed SE more cost-efficient and versatile, and therefore it is used as the building block for designing the switching network. In addition, we deploy the SE to realize 4 × 4 and 8 × 8 BSNs. We also show how the design can be extended for an N × N BSN. All the proposed circuits have been modeled and verified by QCADesigner. QCAPro is used for estimating the average switching and leakage energy dissipation of the proposed circuits. The results show considerable enhancement in terms of cell count, device area, and latency, and thereby outperform all reported prior designs.
IEEE Transactions on Circuits and Systems II: Express Briefs
This brief presents an efficient single-layer serial-parallel multiplier (SPM) in Quantum-dot Cel... more This brief presents an efficient single-layer serial-parallel multiplier (SPM) in Quantum-dot Cellular Automata (QCA). We have designed a bit-serial adder (BSA) using a fully utilized majority gate (MV), and a modified E-shaped exclusive-OR (E-XOR) gate. The cell-interactive properties of the QCA cell have been utilized to realize the proposed E-XOR gate. This new gate leads the proposed SPM to achieve a reduction in cell count and area by 30% and 19%, 29% and 24%, 30% and 22%, 32% and 39%, and 36% and 46% for 4-, 8-, 16-, 32-, and 64-bit multipliers, respectively. All proposed circuits have been simulated and verified by using QCADesigner with a coherence vector simulation engine. In addition, the average switching and leakage energy dissipation are estimated using QCAPro tool.
Quantum-dot Cellular Automata (QCA) is a new nano-innovation in digital systems. It is a possible... more Quantum-dot Cellular Automata (QCA) is a new nano-innovation in digital systems. It is a possible alternative to ordinary CMOS technology. It offers several advantages in reversible logic such as small size and low power dissipation. Therefore, lots of attentions have been paid to implement different reversible QCA circuits. In this way, an improved model of low power odd-parity-bit, generator and checker have been proposed based on the reversible Feynman gate. The proposed reversible odd-parity-bit, generator and checker can be used to check/detect bit loss of information in telecommunication network systems. The proposed parity generator is 57% faster and occupies 38% lesser area than the previous best design. Furthermore, the proposed Nano-communication system dissipates 65% less energy at 0.5 Ek tunneling energy level. A detailed performance evaluation and power analysis are performed in different aspects to authenticate our proposed bit preservation circuits have superb performance in comparison to previously reported works. The results of the proposed circuits have been verified using QCA Designer and the power calculations have been carried out using QCA Pro tool.
IEEE Transactions on Circuits and Systems II: Express Briefs
Quantum-dot cellular automata (QCA) is a new nano-scale technology that due to making significant... more Quantum-dot cellular automata (QCA) is a new nano-scale technology that due to making significant improvements in the design of electronic circuits can be considered as an appropriate alternative to CMOS technology. The arithmetic logic unit (ALU) is a fundamental component of the central processing unit to carry out the arithmetic and logical operations that multiplexer and full adder play an important role in its operations. In this brief, based on the extracted features of the arithmetic operations of the ALU, we propose a new special low-complexity QCA 4:1 multiplexer, which is application-specific to the proposed ALU. Moreover, a new QCA full adder is proposed based on the cell interaction. Likewise, a QCA multilayer ALU structure is designed based on the validated proposed structures to carry out four logical and eight arithmetic operations. The functional correctness of the proposed structures are evaluated by QCADesigner tool; also, QCAPro as an accurate power estimator tool is applied to investigate their power dissipation. The simulation results demonstrate that the proposed structures outperform in comparison to counterpart designs in terms of cell number, area, latency, and power consumption.
Cardiac contusion (CC) is a known complication of blunt trauma to the chest. There have been deba... more Cardiac contusion (CC) is a known complication of blunt trauma to the chest. There have been debates about its true incidence and there are different reports which claim that it occurs in less than 10% to more than 70% of patients. The goal of this study is to estimate the incidence of CC in patients with severe blunt chest trauma (SBCT) using transthoracic echocardiography (TTE). After defining inclusion and exclusion criteria, all cases with clinical evidences of SBCT from February 2010 until October 2011 were included in this study. Patients were assessed using electrocardiography (ECG) and transthoracic echocardiography (TTE). Transient echocardiographic changes, including wall motion abnormalities, valvular or papillary muscle dysfunction, pericardial effusion or tamponade, free wall rupture and interatrial/interventricular septum defects, were considered to be abnormal and trauma-related. A total of 210 patients were assessed for CC. Fifty-two trauma-related echocardiographic changes in 47 patients were observed, in which 34 cases had simultaneous transient ECG changes. The estimated incidence of CC in these subjects was calculated to be 23.38% and 16.19%, respectively. There was a statistically significant relationship between the presence of both echocardiographic changes and ECG abnormalities, and those subjects without ECG changes (P = 0.03). As we evaluated stable patients without any cardiac-related clinical manifestations and TTE was chosen as our diagnostic modality, we claim that the true incidence must be higher. We believe that a comparison of our findings with those presented in the literature shows that the actual incidence of CC in blunt chest trauma is underestimated.
For immense demand of speedy high-end gadgets, chips are becoming denser, but Moore's law is ... more For immense demand of speedy high-end gadgets, chips are becoming denser, but Moore's law is falling flat lately. Complementary Metal-Oxide-Semiconductor (CMOS) technology is on its brink. Quantum-dot cellular automata (QCA) has become a potential alternative technology to provide faster speed with low power dissipation at nano-scale extent. Here, we proposed an efficient QCA design of 1-bit comparator. The proposed comparator required 59% less area and dissipated 82% less energy. QCA Designer has been used to design and simulate the proposed comparator. Finally, QCAPro tool has been employed for estimating energy dissipation. Özet. Hızlı üst düzey cihazların büyük talepleri için çipler yoğunlaşmakta ancak Moore yasası son zamanlarda düşmektedir. Tamamlayıcı Metal-Oksit-Yarı iletken (CMOS) teknolojisi eşiğe ulaşmıştır. Kuantum noktalı hücresel otomasyon (QCA), nano ölçekte düşük güç dağılımıyla daha hızlı bir hız sağlamak için potansiyel bir alternatif teknoloji haline gelmiştir...
— Quantum dot Cellular Automata (QCA) is anticipated to allow for extremely dense nano-scale desi... more — Quantum dot Cellular Automata (QCA) is anticipated to allow for extremely dense nano-scale design and implementation of logic circuit over the Complementary Metal Oxide Semiconductor (CMOS). QCA has been considered as a promising alternative to CMOS technology for its lower power consumption, higher scale integration and higher switching frequency. Moreover, the basic element in QCA is majority gate. This paper present Double Feynman Gate (F2G) based on QCA logic gates: the QCA wire, MV gate and Inverter gate. The proposed circuit is designed and verified using QCADesigner. Keywords- QCA, QCA Logic Gates, Double Feynman Gate (F2G), MV, Inverter gate I.
2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE)
Diabetes Mellitus (DM) or diabetes is one of the metabolic diseases exhibiting high blood glucose... more Diabetes Mellitus (DM) or diabetes is one of the metabolic diseases exhibiting high blood glucose level over a prolonged period. The management of diabetes is associated with the proper monitoring of blood glucose level. Researchers have been working on developing robust techniques to monitor the level of glucose in the blood. This paper aims at predicting blood glucose levels based on NIR spectroscopic response data utilizing machine learning techniques. Blood glucose samples were prepared in a controlled environment and the NIR spectrums of the samples were obtained using NeoSpectraMicro development kit. Two machine learning approaches have been employed to analyze the experimental dataset. Firstly, the Random Forest Algorithm (RF) followed by Support Vector Machine (SVM) has been utilized that provides an accuracy of 67.5%. Then, a combination of Principle Component Analysis (PCA) and SVM is used. PCA followed by SVM shows a promising result of 77.5% accuracy compared to the previous technique. The numerical findings reveal that the NIR spectroscopy with appropriate data modeling algorithm can be a potential candidate for non-invasive blood glucose monitoring system.
Quantum Dot Cellular Automata (QCA) is a promising nanotechnology in Quantum electronics for its ... more Quantum Dot Cellular Automata (QCA) is a promising nanotechnology in Quantum electronics for its ultra low power consumption, faster speed and small size features . It has significant advantages over the Complementary Metal–Oxide–Semiconductor (CMOS) technology. This paper present , a novel QCA representation of Six-Correction Logic (SCL) gate based on QCA logic gates: the Maj 3 , Maj AND gate and Maj OR. In order to design and verify the functionality of the proposed layout, QCADesigner a familiar QCA simulator has been employed. The simulation results confirm correctness of the claims and its usefulness in designing a digital circuits.
Abstract A numerical simulation and substantiation have been accomplished to analyze the impact o... more Abstract A numerical simulation and substantiation have been accomplished to analyze the impact of Al0.9Ga0.1As alloy composite buffer layer band gap and thickness, absorber layer thickness on a ZnO:Al/i-ZnO/Al0.9Ga0.1As/CIGS/Mo/SLG structured non-toxic Cd-free CIGS photovoltaic cell. In this study, the cell output attributes including efficiency (η) and collection efficiency (ηc) have been optimized through short circuit current density (Jsc), open-circuit voltage (Voc) and fill factor (FF) optimization. Our study has been concluded with the maximum efficiency of 24.32% with Voc = 839.76 mV, Jsc = 36.21mA/cm2 and FF=76.96%, ηc = 83.16%. This enhanced efficiency is optimized by determining the bandgap of the buffer through altering the Al concentration to transit it from direct bandgap material to an indirect one. The thickness of the absorber on system performance is also investigated, and its extent is found in between 2 µm to 3 µm.
A crop’s health can be determined by its leaf nutrient status; more precisely, leaf nitrogen (N) ... more A crop’s health can be determined by its leaf nutrient status; more precisely, leaf nitrogen (N) level, is a critical indicator that carries a lot of worthwhile nutrient information for classifying the plant’s health. However, the existing non-invasive techniques are expensive and bulky. The aim of this study is to develop a low-cost, quick-read multi-spectral sensor array to predict N level in leaves non-invasively. The proposed sensor module has been developed using two reflectance-based multi-spectral sensors (visible and near-infrared (NIR)). In addition, the proposed device can capture the reflectance data at 12 different wavelengths (six for each sensor). We conducted the experiment on canola leaves in a controlled greenhouse environment as well as in the field. In the greenhouse experiment, spectral data were collected from 87 leaves of 24 canola plants, subjected to varying levels of N fertilization. Later, 42 canola cultivars were subjected to low and high nitrogen levels i...
IEEE Transactions on Very Large Scale Integration (VLSI) Systems
Quantum-dot cellular automata (QCA) is recognized as one of the rapidly growing nanotechnologies ... more Quantum-dot cellular automata (QCA) is recognized as one of the rapidly growing nanotechnologies and an alternate to CMOS at the nanoscale. The QCA technology is capable of designing nanoscale digital circuits with a clock speed of terahertz range and ultralow power consumption. In this article, an effective single-layer binary discrete cosine transform (BinDCT) has been reported. To realize the BinDCT architecture in QCA, we also proposed several associated combinational and sequential logic elements of low complexity. All reported circuit layouts were designed and verified using the QCADesigner tool. Moreover, QCAPro is used to estimate the energy dissipation. All comparative study indicates that the reported designs are superior to previous designs in terms of cell complexity, covered area, and energy dissipation. In particular, the proposed QCA BinDCT achieved 39% cell count and 20% covered area improvements compared with the previous QCA BinDCT architecture. Moreover, in terms of power dissipation, the proposed QCA BinDCT dissipates $1.394 \times 10^{-4}$ mW, whereas CMOS- and QCA-based BinDCT architectures consume 0.195 and 0.091 mW of power, respectively.
Quantum-dot cellular automata (QCA) is a rapidly growing nanotechnology very well suited for desi... more Quantum-dot cellular automata (QCA) is a rapidly growing nanotechnology very well suited for designing ultra-dense, low-power, and high-performance digital circuits. In parallel computing, the multistage interconnection network (MIN) provides maximum bandwidth to the components and minimum latency access to the memory modules. Much research has been conducted on CMOS-based MINs for parallel computing. However, the QCA-based switching network is still underexplored. This article proposes a QCA architecture of a new single-layer butterfly switching network (BSN). To achieve this, we design an efficient 2 × 2 switching element (SE), using a modified majority ($\mathcal{M}{_{[x,y]}}$) gate that is fully utilized (i.e., no fixed logic like “0” and “1” at the inputs). The use of a fully utilized majority gate over a partially utilized majority (PUM) one makes the proposed SE more cost-efficient and versatile, and therefore it is used as the building block for designing the switching network. In addition, we deploy the SE to realize 4 × 4 and 8 × 8 BSNs. We also show how the design can be extended for an N × N BSN. All the proposed circuits have been modeled and verified by QCADesigner. QCAPro is used for estimating the average switching and leakage energy dissipation of the proposed circuits. The results show considerable enhancement in terms of cell count, device area, and latency, and thereby outperform all reported prior designs.
IEEE Transactions on Circuits and Systems II: Express Briefs
This brief presents an efficient single-layer serial-parallel multiplier (SPM) in Quantum-dot Cel... more This brief presents an efficient single-layer serial-parallel multiplier (SPM) in Quantum-dot Cellular Automata (QCA). We have designed a bit-serial adder (BSA) using a fully utilized majority gate (MV), and a modified E-shaped exclusive-OR (E-XOR) gate. The cell-interactive properties of the QCA cell have been utilized to realize the proposed E-XOR gate. This new gate leads the proposed SPM to achieve a reduction in cell count and area by 30% and 19%, 29% and 24%, 30% and 22%, 32% and 39%, and 36% and 46% for 4-, 8-, 16-, 32-, and 64-bit multipliers, respectively. All proposed circuits have been simulated and verified by using QCADesigner with a coherence vector simulation engine. In addition, the average switching and leakage energy dissipation are estimated using QCAPro tool.
Quantum-dot Cellular Automata (QCA) is a new nano-innovation in digital systems. It is a possible... more Quantum-dot Cellular Automata (QCA) is a new nano-innovation in digital systems. It is a possible alternative to ordinary CMOS technology. It offers several advantages in reversible logic such as small size and low power dissipation. Therefore, lots of attentions have been paid to implement different reversible QCA circuits. In this way, an improved model of low power odd-parity-bit, generator and checker have been proposed based on the reversible Feynman gate. The proposed reversible odd-parity-bit, generator and checker can be used to check/detect bit loss of information in telecommunication network systems. The proposed parity generator is 57% faster and occupies 38% lesser area than the previous best design. Furthermore, the proposed Nano-communication system dissipates 65% less energy at 0.5 Ek tunneling energy level. A detailed performance evaluation and power analysis are performed in different aspects to authenticate our proposed bit preservation circuits have superb performance in comparison to previously reported works. The results of the proposed circuits have been verified using QCA Designer and the power calculations have been carried out using QCA Pro tool.
IEEE Transactions on Circuits and Systems II: Express Briefs
Quantum-dot cellular automata (QCA) is a new nano-scale technology that due to making significant... more Quantum-dot cellular automata (QCA) is a new nano-scale technology that due to making significant improvements in the design of electronic circuits can be considered as an appropriate alternative to CMOS technology. The arithmetic logic unit (ALU) is a fundamental component of the central processing unit to carry out the arithmetic and logical operations that multiplexer and full adder play an important role in its operations. In this brief, based on the extracted features of the arithmetic operations of the ALU, we propose a new special low-complexity QCA 4:1 multiplexer, which is application-specific to the proposed ALU. Moreover, a new QCA full adder is proposed based on the cell interaction. Likewise, a QCA multilayer ALU structure is designed based on the validated proposed structures to carry out four logical and eight arithmetic operations. The functional correctness of the proposed structures are evaluated by QCADesigner tool; also, QCAPro as an accurate power estimator tool is applied to investigate their power dissipation. The simulation results demonstrate that the proposed structures outperform in comparison to counterpart designs in terms of cell number, area, latency, and power consumption.
Cardiac contusion (CC) is a known complication of blunt trauma to the chest. There have been deba... more Cardiac contusion (CC) is a known complication of blunt trauma to the chest. There have been debates about its true incidence and there are different reports which claim that it occurs in less than 10% to more than 70% of patients. The goal of this study is to estimate the incidence of CC in patients with severe blunt chest trauma (SBCT) using transthoracic echocardiography (TTE). After defining inclusion and exclusion criteria, all cases with clinical evidences of SBCT from February 2010 until October 2011 were included in this study. Patients were assessed using electrocardiography (ECG) and transthoracic echocardiography (TTE). Transient echocardiographic changes, including wall motion abnormalities, valvular or papillary muscle dysfunction, pericardial effusion or tamponade, free wall rupture and interatrial/interventricular septum defects, were considered to be abnormal and trauma-related. A total of 210 patients were assessed for CC. Fifty-two trauma-related echocardiographic changes in 47 patients were observed, in which 34 cases had simultaneous transient ECG changes. The estimated incidence of CC in these subjects was calculated to be 23.38% and 16.19%, respectively. There was a statistically significant relationship between the presence of both echocardiographic changes and ECG abnormalities, and those subjects without ECG changes (P = 0.03). As we evaluated stable patients without any cardiac-related clinical manifestations and TTE was chosen as our diagnostic modality, we claim that the true incidence must be higher. We believe that a comparison of our findings with those presented in the literature shows that the actual incidence of CC in blunt chest trauma is underestimated.
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