Eyes are foremost blessing to enjoy the nature. Blind people face lot of hurdles in daily life. B... more Eyes are foremost blessing to enjoy the nature. Blind people face lot of hurdles in daily life. Blind people needs to depend on others to perform their normal life activities. Information technology brings revolution in every field of life with emerging artificial intelligence, internet of things, wireless sensor networks etc. Internet of Things is evolving technology that digitally interconnect the humans, machines, sensors and everything for automation. It transform manual processes to intelligent automated processes with the help of aritifical intelligence. In this research, we have developed a sensitive smart stick empowered by Interent of Things to support the visually impaired peoples. Smart stick is incorporated with ultrasonic sensor and buzzer to sense and alarm in case of any hurdle. Andorid application is developed with smart stick to generate the important notification and forward to registered numbers along with GPS location. This solution is cost effective and implemen...
International Journal of Environmental Research and Public Health
The relationship between environmental factors and child health is not well understood in rural P... more The relationship between environmental factors and child health is not well understood in rural Pakistan. This study characterized the environmental factors related to the morbidity of acute respiratory infections (ARIs), diarrhea, and growth using geographical information systems (GIS) technology. Anthropometric, address and disease prevalence data were collected through the SEEM (Study of Environmental Enteropathy and Malnutrition) study in Matiari, Pakistan. Publicly available map data were used to compile coordinates of healthcare facilities. A Pearson correlation coefficient (r) was used to calculate the correlation between distance from healthcare facilities and participant growth and morbidity. Other continuous variables influencing these outcomes were analyzed using a random forest regression model. In this study of 416 children, we found that participants living closer to secondary hospitals had a lower prevalence of ARI (r = 0.154, p < 0.010) and diarrhea (r = 0.228, p ...
Pakistan Journal of Humanities and Social Sciences
Entrepreneurial orientation, entrepreneurial innovation, and knowledge management all play critic... more Entrepreneurial orientation, entrepreneurial innovation, and knowledge management all play critical roles in improving the performance of Pakistan's small and medium-sized enterprises (SMEs). Pakistan's business index score decreased from 137th to 138th due to the country's low performance in the small and medium-sized enterprise sector. Small and medium-sized firms must overcome several obstacles in order for the country's economy to thrive. This study will address this issue. We used a cross-sectional design and a quantitative technique in our research. Data were acquired via an email questionnaire and analyzed using the structural equation modeling technique and SmartPls. The findings suggested that entrepreneur orientation and innovation are critical factors in enhancing the success of SMEs. Additionally, knowledge management acts as a buffer between entrepreneurial attitude and organizational performance, as well as between entrepreneurial innovation and organiz...
Rice is a primary food for more than three billion people worldwide and cultivated on about 12% o... more Rice is a primary food for more than three billion people worldwide and cultivated on about 12% of the world’s arable land. However, more than 88% production is observed in Asian countries, including Pakistan. Due to higher population growth and recent climate change scenarios, it is crucial to get timely and accurate rice yield estimates and production forecast of the growing season for governments, planners, and decision makers in formulating policies regarding import/export in the event of shortfall and/or surplus. This study aims to quantify the rice yield at various phenological stages from hyper-temporal satellite-derived-vegetation indices computed from time series Sentinel-II images. Different vegetation indices (viz. NDVI, EVI, SAVI, and REP) were used to predict paddy yield. The predicted yield was validated through RMSE and ME statistical techniques. The integration of PLSR and sequential time-stamped vegetation indices accurately predicted rice yield (i.e., maximum R2 = ...
Herein, we report a protocol for highly efficient hypervalent iodine (III) mediated, group-assist... more Herein, we report a protocol for highly efficient hypervalent iodine (III) mediated, group-assisted purification (GAP) method for the regioselectivities and stereoselective aminochlorination of electron-deficient olefins. A series of vicinal chloramines with multifunctionalities were acquired in moderate to excellent yields (45–94%), by merely mixing the GAP auxiliary-anchored substrates with dichloramine T and tosylamide as chlorine/nitrogen sources and iodobenzene diacetate as a catalyst. The vicinal chloramines were obtained without any column chromatographic purification and recrystallization simply by washing the reaction mixture with a minimum amount of common inexpensive solvents and thus avoiding wastage of silica, solvents, time, and labor. The GAP auxiliary is recyclable and reusable. This strategy is easy to handle, cost-effective, greener, sustainable, environmentally benign, and mostly suitable for the syntheses of vicinal haloamines from various electron-deficient alkenes.
Presentation attack artefacts can be used to subvert the operation of biometric systems by being ... more Presentation attack artefacts can be used to subvert the operation of biometric systems by being presented to the sensors of such systems. In this work, we propose the use of visual stimuli with randomised trajectories to stimulate eye movements for the detection of such spoofing attacks. The presentation of a moving visual challenge is used to ensure that some pupillary motion is stimulated and then captured with a camera. Various types of challenge trajectories are explored on different planar geometries representing prospective devices where the challenge could be presented to users. To evaluate the system, photo, 2D mask and 3D mask attack artefacts were used and pupillary movement data were captured from 80 volunteers performing genuine and spoofing attempts. The results support the potential of the proposed features for the detection of biometric presentation attacks.
Image classification is central to the big data revolution in medicine. Improved information proc... more Image classification is central to the big data revolution in medicine. Improved information processing methods for diagnosis and classification of digital medical images have shown to be successful via deep learning approaches. As this field is explored, there are limitations to the performance of traditional supervised classifiers. This paper outlines an approach that is different from the current medical image classification tasks that view the issue as multi-class classification. We performed a hierarchical classification using our Hierarchical Medical Image classification (HMIC) approach. HMIC uses stacks of deep learning models to give particular comprehension at each level of the clinical picture hierarchy. For testing our performance, we use biopsy of the small bowel images that contain three categories in the parent level (Celiac Disease, Environmental Enteropathy, and histologically normal controls). For the child level, Celiac Disease Severity is classified into 4 classes...
Connected graphs with minimum degree $\delta$ and at least $2\delta + 1$ vertices have paths with... more Connected graphs with minimum degree $\delta$ and at least $2\delta + 1$ vertices have paths with at least $2\delta + 1$ vertices. We provide a characterization of all such graphs which have no longer paths.
To explore effects of program-generated music on physiological, metabolic and endocrine responses... more To explore effects of program-generated music on physiological, metabolic and endocrine responses. Five healthy males underwent whole-body calorimetry using a standard protocol on three separate days, with no music on day 1 (D1), and genre-specific music from online computer-generated program on days 2 (D2: random track selection) and 3 (D3: track selection based on subject-inputted mood). Measurements included pulse, blood pressure (BP), and blood samples for serum cortisol. A p-value ≤ 0.05 was considered significant. Compared with D1, overall metabolic rate during D2 and D3 was reduced by 54.7 kcal (p = 0.03) and 70.6kcal (p = 0.01), respectively, and daytime drop in serum cortisol level was lessened by 125 mmol/l (p = 0.02) and 45 mmol/l (p = 0.04), respectively. Acute effects of music on BP were dependent on genre-specific popularity. Computer-generated music reduces overall metabolic rate, influences cortisol diurnal rhythm and has acute effects on physiological responses based on genre-preference.
Introduction: Recent data on effects of hyperoxia in patients with coronary artery disease, brain... more Introduction: Recent data on effects of hyperoxia in patients with coronary artery disease, brain injury [1] and post resuscitation patients [2] have shown increased mortality and morbidity. This calls for efforts to reduce unnecessary oxygen use in hospitals, which we instituted via targeted multidisciplinary education and widening the use of electronic prescription of oxygen between 2008 and 2010. Method: Cross-sectional point prevalence of oxygen prescribing practice was audited at our teaching hospital in November 2008 and November 2010 excluding Intensive care, paediatric and maternity wards. Between the 2 oxygen audits, we widened and improved electronic prescribing with a multidisciplinary training program on oxygen use for all caregivers. Results: At the Nov 2010 point of data collection, 185/1267 (15%) patients were on oxygen. Of these a clear valid oxygen prescription was noted in 149 (81%); 46% of saturations documented were within target range. The proportion of patients...
Breast milk contains anti-rotavirus IgA antibodies and other innate immune factors that inhibit r... more Breast milk contains anti-rotavirus IgA antibodies and other innate immune factors that inhibit rotavirus replication in vitro. These factors could diminish the immunogenicity of oral rotavirus vaccines, particularly if breastfeeding occurs close to the time of vaccine administration. Between April 2011 and November 2012, we conducted an open label, randomized trial to compare the immunogenicity of Rotarix (RV1) in infants whose breastfeeding was withheld one hour before through one hour after vaccination with that in infants breastfed at the time of vaccination. The trial was conducted in the peri-urban area of Ibrahim Hyderi in Karachi, Pakistan. Both groups received three doses of RV1 at 6, 10 and 14 weeks of age. Seroconversion (anti-rotavirus IgA antibodies ≥20 U/mL in subjects seronegative at 6 weeks of age) following three vaccine doses (6, 10 and 14 weeks) was determined at 18 weeks of age (primary objective) and seroconversion following two doses (6 and 10 weeks) was determ...
2012 IEEE 51st IEEE Conference on Decision and Control (CDC), 2012
Traditional system identification uses measurements of the inputs, but when these measurements ar... more Traditional system identification uses measurements of the inputs, but when these measurements are not available, alternative methods, such as blind identification, output-only identification, or operational modal analysis, must be used. Yet another method is sensor-to-sensor identification (S2SID), which estimates pseudo transfer functions whose inputs are outputs of the original system. A special case of S2SID is transmissibility identification. Since S2SID depends on cancellation of the input, this approach does not extend to nonlinear systems. However, in the present paper we show that, for the case of a two-output Hammerstein system, the leastsquares estimate of the PTF is consistent, that is, asymptotically correct, despite the presence of the nonlinearities.
We consider the problem of estimating the unknown solar driver F10.7 and physical states in the i... more We consider the problem of estimating the unknown solar driver F10.7 and physical states in the ionosphere and thermosphere using retrospective cost adaptive state estimation (RCASE). We interface RCASE with the Global Ionosphere Thermosphere Model (GITM) to demonstrate state estimation and F10.7 input reconstruction. We further examine the various factors that affect F10.7 estimation including saturation limits, initial estimates, and RCASE tuning parameters.
Current oral rotavirus vaccines perform suboptimally in resource-poor settings. We investigated t... more Current oral rotavirus vaccines perform suboptimally in resource-poor settings. We investigated the effect of an additional dose and later schedule on the immunogenicity of monovalent rotavirus vaccine (RV1) in a developing country. Infants received RV1 at 6 and 10, 10 and 14, or 6, 10, and 14 weeks of age. The primary objective was to compare antirotavirus immunoglobulin A (IgA) seroconversion at 18 weeks in the 6/10/14 arm to the cumulative seroconversion (highest result at 14 or 18 weeks) in the 6/10 arm. Overall, 480 (76.2%) of 630 randomized infants completed the trial per protocol. Seroconversion in the 6/10/14 arm was 36.7% (95% CI, 29.8, 44.2) compared to 36.1% (CI, 29.0, 43.9) in the 6/10 arm, (P=1.0); the result from the 10/14 arm was 38.5% (CI, 31.2, 46.3). Seroconversion in the 6/10 arm at 14 weeks (post hoc) was lower at 29.7% (CI, 23.1, 37.3). In Pakistani infants, the immunogenicity of RV1 did not increase significantly with 3 doses at 6, 10, and 14 weeks compared to ...
Connected graphs with minimum degree δ and at least 2δ + 1 vertices have paths with at least 2δ +... more Connected graphs with minimum degree δ and at least 2δ + 1 vertices have paths with at least 2δ + 1 vertices. We provide a characterization of all such graphs which have no longer paths. Extremal problems involving paths and cycles have been considered since the infancy of graph theory. The question which interests us here is the question of what minimum degree condition guarantees a path of a preassigned length. This question was answered by Erdös and Gallai [4] and again by Andrasfai [1]. Our formulation of their answer is Theorem 1 Let G be a connected graph with minimum degree δ and at least 2δ + 1 vertices. Then G contains a path of at least 2δ + 1 vertices.
Volume 1: Adaptive Control; Advanced Vehicle Propulsion Systems; Aerospace Systems; Autonomous Systems; Battery Modeling; Biochemical Systems; Control Over Networks; Control Systems Design; Cooperativ, 2012
Health management of Li-ion batteries depends on knowledge of certain battery internal dynamics (... more Health management of Li-ion batteries depends on knowledge of certain battery internal dynamics (e.g., lithium consumption and film growth at the solid-electrolyte interface) whose inputs and outputs are not directly measurable with noninvasive methods. This presents a problem of identification of inaccessible subsystems. To address this problem, we apply the retrospective-cost subsystem identification (RCSI) method. As a first step, this paper presents a simulation-based study that assumes as the truth model of the battery an electrochemistrybased battery charge/discharge model of Doyle, Fuller, and Newman, and later augmented with a battery-health model by Ramadass. First, this truth model is used to generate the data needed for the identification study. Next, the film-growth component of the battery-health model is assumed to be unknown, and the identification of this inaccessible subsystem is performed using RCSI. The results show that the subsystem identification method can identify the film growth quite accurately when the chemical reactions leading to film growth are consequential.
With advances in miniaturization, wireless communication, and the theory of selforganizing system... more With advances in miniaturization, wireless communication, and the theory of selforganizing systems, it has become possible to consider scenarios where a very large number of networkable sensors are deployed randomly over an extended environment and organize themselves into a network. Such networks-which we term largescale sensor networks (LSSN's)-can be useful in many situations, including military surveillance, environmental monitoring, disaster relief, etc. The idea is that, by deploying an LSSN, an extended environment can be rendered observable for an external user (e.g., a monitoring station) or for users within the system (e.g., persons walking around with palm-sized devices). Unlike custom-designed networks, these randomly deployed networks need no pre-design and configure themselves through a process of self-organization. The sensor nodes themselves are typically anonymous, and information is addressed by location or attribute rather than by node ID. This approach provides several advantages, including: 1) Scalability; 2) Robustness; 3) Flexibility; 4) Expandability; and 5) Versatility. Indeed, this abstraction is implicit in such ideas as smart paint, smart dust, and smart matter. The purpose of our research is to explore how a system comprising a very large number of randomly distributed nodes can organize itself to communicate information between designated geographical locations. To keep the system realistic, we assume that each node has only limited reliability, energy resources, wireless communication capabilities, and computational capacity. Thus, direct long-range communication between nodes is not possible, and most messaging involves a large number of "hops" between neighboring nodes. In particular, we are interested in obtaining reliable communication at the system level from simple, unreliable nodes.
Proceedings of the 2011 American Control Conference, 2011
We present a growing-window variableregularization recursive least squares (GW-VR-RLS) algorithm.... more We present a growing-window variableregularization recursive least squares (GW-VR-RLS) algorithm. Standard recursive least squares (RLS) uses a time-invariant regularization. More specifically, the inverse of the initial covariance matrix in classical RLS can be viewed as a regularization term, which weights the difference between the next state estimate and the initial state estimate. The present paper allows for time-varying in the weighting as well as what is being weighted. This extension can be used to modulate the speed of convergence of the estimates versus the magnitude of transient estimation errors. Furthermore, the regularization term can weight the difference between the next state estimate and a time-varying vector of parameters rather than the initial state estimate as is required in standard RLS.
Eyes are foremost blessing to enjoy the nature. Blind people face lot of hurdles in daily life. B... more Eyes are foremost blessing to enjoy the nature. Blind people face lot of hurdles in daily life. Blind people needs to depend on others to perform their normal life activities. Information technology brings revolution in every field of life with emerging artificial intelligence, internet of things, wireless sensor networks etc. Internet of Things is evolving technology that digitally interconnect the humans, machines, sensors and everything for automation. It transform manual processes to intelligent automated processes with the help of aritifical intelligence. In this research, we have developed a sensitive smart stick empowered by Interent of Things to support the visually impaired peoples. Smart stick is incorporated with ultrasonic sensor and buzzer to sense and alarm in case of any hurdle. Andorid application is developed with smart stick to generate the important notification and forward to registered numbers along with GPS location. This solution is cost effective and implemen...
International Journal of Environmental Research and Public Health
The relationship between environmental factors and child health is not well understood in rural P... more The relationship between environmental factors and child health is not well understood in rural Pakistan. This study characterized the environmental factors related to the morbidity of acute respiratory infections (ARIs), diarrhea, and growth using geographical information systems (GIS) technology. Anthropometric, address and disease prevalence data were collected through the SEEM (Study of Environmental Enteropathy and Malnutrition) study in Matiari, Pakistan. Publicly available map data were used to compile coordinates of healthcare facilities. A Pearson correlation coefficient (r) was used to calculate the correlation between distance from healthcare facilities and participant growth and morbidity. Other continuous variables influencing these outcomes were analyzed using a random forest regression model. In this study of 416 children, we found that participants living closer to secondary hospitals had a lower prevalence of ARI (r = 0.154, p < 0.010) and diarrhea (r = 0.228, p ...
Pakistan Journal of Humanities and Social Sciences
Entrepreneurial orientation, entrepreneurial innovation, and knowledge management all play critic... more Entrepreneurial orientation, entrepreneurial innovation, and knowledge management all play critical roles in improving the performance of Pakistan's small and medium-sized enterprises (SMEs). Pakistan's business index score decreased from 137th to 138th due to the country's low performance in the small and medium-sized enterprise sector. Small and medium-sized firms must overcome several obstacles in order for the country's economy to thrive. This study will address this issue. We used a cross-sectional design and a quantitative technique in our research. Data were acquired via an email questionnaire and analyzed using the structural equation modeling technique and SmartPls. The findings suggested that entrepreneur orientation and innovation are critical factors in enhancing the success of SMEs. Additionally, knowledge management acts as a buffer between entrepreneurial attitude and organizational performance, as well as between entrepreneurial innovation and organiz...
Rice is a primary food for more than three billion people worldwide and cultivated on about 12% o... more Rice is a primary food for more than three billion people worldwide and cultivated on about 12% of the world’s arable land. However, more than 88% production is observed in Asian countries, including Pakistan. Due to higher population growth and recent climate change scenarios, it is crucial to get timely and accurate rice yield estimates and production forecast of the growing season for governments, planners, and decision makers in formulating policies regarding import/export in the event of shortfall and/or surplus. This study aims to quantify the rice yield at various phenological stages from hyper-temporal satellite-derived-vegetation indices computed from time series Sentinel-II images. Different vegetation indices (viz. NDVI, EVI, SAVI, and REP) were used to predict paddy yield. The predicted yield was validated through RMSE and ME statistical techniques. The integration of PLSR and sequential time-stamped vegetation indices accurately predicted rice yield (i.e., maximum R2 = ...
Herein, we report a protocol for highly efficient hypervalent iodine (III) mediated, group-assist... more Herein, we report a protocol for highly efficient hypervalent iodine (III) mediated, group-assisted purification (GAP) method for the regioselectivities and stereoselective aminochlorination of electron-deficient olefins. A series of vicinal chloramines with multifunctionalities were acquired in moderate to excellent yields (45–94%), by merely mixing the GAP auxiliary-anchored substrates with dichloramine T and tosylamide as chlorine/nitrogen sources and iodobenzene diacetate as a catalyst. The vicinal chloramines were obtained without any column chromatographic purification and recrystallization simply by washing the reaction mixture with a minimum amount of common inexpensive solvents and thus avoiding wastage of silica, solvents, time, and labor. The GAP auxiliary is recyclable and reusable. This strategy is easy to handle, cost-effective, greener, sustainable, environmentally benign, and mostly suitable for the syntheses of vicinal haloamines from various electron-deficient alkenes.
Presentation attack artefacts can be used to subvert the operation of biometric systems by being ... more Presentation attack artefacts can be used to subvert the operation of biometric systems by being presented to the sensors of such systems. In this work, we propose the use of visual stimuli with randomised trajectories to stimulate eye movements for the detection of such spoofing attacks. The presentation of a moving visual challenge is used to ensure that some pupillary motion is stimulated and then captured with a camera. Various types of challenge trajectories are explored on different planar geometries representing prospective devices where the challenge could be presented to users. To evaluate the system, photo, 2D mask and 3D mask attack artefacts were used and pupillary movement data were captured from 80 volunteers performing genuine and spoofing attempts. The results support the potential of the proposed features for the detection of biometric presentation attacks.
Image classification is central to the big data revolution in medicine. Improved information proc... more Image classification is central to the big data revolution in medicine. Improved information processing methods for diagnosis and classification of digital medical images have shown to be successful via deep learning approaches. As this field is explored, there are limitations to the performance of traditional supervised classifiers. This paper outlines an approach that is different from the current medical image classification tasks that view the issue as multi-class classification. We performed a hierarchical classification using our Hierarchical Medical Image classification (HMIC) approach. HMIC uses stacks of deep learning models to give particular comprehension at each level of the clinical picture hierarchy. For testing our performance, we use biopsy of the small bowel images that contain three categories in the parent level (Celiac Disease, Environmental Enteropathy, and histologically normal controls). For the child level, Celiac Disease Severity is classified into 4 classes...
Connected graphs with minimum degree $\delta$ and at least $2\delta + 1$ vertices have paths with... more Connected graphs with minimum degree $\delta$ and at least $2\delta + 1$ vertices have paths with at least $2\delta + 1$ vertices. We provide a characterization of all such graphs which have no longer paths.
To explore effects of program-generated music on physiological, metabolic and endocrine responses... more To explore effects of program-generated music on physiological, metabolic and endocrine responses. Five healthy males underwent whole-body calorimetry using a standard protocol on three separate days, with no music on day 1 (D1), and genre-specific music from online computer-generated program on days 2 (D2: random track selection) and 3 (D3: track selection based on subject-inputted mood). Measurements included pulse, blood pressure (BP), and blood samples for serum cortisol. A p-value ≤ 0.05 was considered significant. Compared with D1, overall metabolic rate during D2 and D3 was reduced by 54.7 kcal (p = 0.03) and 70.6kcal (p = 0.01), respectively, and daytime drop in serum cortisol level was lessened by 125 mmol/l (p = 0.02) and 45 mmol/l (p = 0.04), respectively. Acute effects of music on BP were dependent on genre-specific popularity. Computer-generated music reduces overall metabolic rate, influences cortisol diurnal rhythm and has acute effects on physiological responses based on genre-preference.
Introduction: Recent data on effects of hyperoxia in patients with coronary artery disease, brain... more Introduction: Recent data on effects of hyperoxia in patients with coronary artery disease, brain injury [1] and post resuscitation patients [2] have shown increased mortality and morbidity. This calls for efforts to reduce unnecessary oxygen use in hospitals, which we instituted via targeted multidisciplinary education and widening the use of electronic prescription of oxygen between 2008 and 2010. Method: Cross-sectional point prevalence of oxygen prescribing practice was audited at our teaching hospital in November 2008 and November 2010 excluding Intensive care, paediatric and maternity wards. Between the 2 oxygen audits, we widened and improved electronic prescribing with a multidisciplinary training program on oxygen use for all caregivers. Results: At the Nov 2010 point of data collection, 185/1267 (15%) patients were on oxygen. Of these a clear valid oxygen prescription was noted in 149 (81%); 46% of saturations documented were within target range. The proportion of patients...
Breast milk contains anti-rotavirus IgA antibodies and other innate immune factors that inhibit r... more Breast milk contains anti-rotavirus IgA antibodies and other innate immune factors that inhibit rotavirus replication in vitro. These factors could diminish the immunogenicity of oral rotavirus vaccines, particularly if breastfeeding occurs close to the time of vaccine administration. Between April 2011 and November 2012, we conducted an open label, randomized trial to compare the immunogenicity of Rotarix (RV1) in infants whose breastfeeding was withheld one hour before through one hour after vaccination with that in infants breastfed at the time of vaccination. The trial was conducted in the peri-urban area of Ibrahim Hyderi in Karachi, Pakistan. Both groups received three doses of RV1 at 6, 10 and 14 weeks of age. Seroconversion (anti-rotavirus IgA antibodies ≥20 U/mL in subjects seronegative at 6 weeks of age) following three vaccine doses (6, 10 and 14 weeks) was determined at 18 weeks of age (primary objective) and seroconversion following two doses (6 and 10 weeks) was determ...
2012 IEEE 51st IEEE Conference on Decision and Control (CDC), 2012
Traditional system identification uses measurements of the inputs, but when these measurements ar... more Traditional system identification uses measurements of the inputs, but when these measurements are not available, alternative methods, such as blind identification, output-only identification, or operational modal analysis, must be used. Yet another method is sensor-to-sensor identification (S2SID), which estimates pseudo transfer functions whose inputs are outputs of the original system. A special case of S2SID is transmissibility identification. Since S2SID depends on cancellation of the input, this approach does not extend to nonlinear systems. However, in the present paper we show that, for the case of a two-output Hammerstein system, the leastsquares estimate of the PTF is consistent, that is, asymptotically correct, despite the presence of the nonlinearities.
We consider the problem of estimating the unknown solar driver F10.7 and physical states in the i... more We consider the problem of estimating the unknown solar driver F10.7 and physical states in the ionosphere and thermosphere using retrospective cost adaptive state estimation (RCASE). We interface RCASE with the Global Ionosphere Thermosphere Model (GITM) to demonstrate state estimation and F10.7 input reconstruction. We further examine the various factors that affect F10.7 estimation including saturation limits, initial estimates, and RCASE tuning parameters.
Current oral rotavirus vaccines perform suboptimally in resource-poor settings. We investigated t... more Current oral rotavirus vaccines perform suboptimally in resource-poor settings. We investigated the effect of an additional dose and later schedule on the immunogenicity of monovalent rotavirus vaccine (RV1) in a developing country. Infants received RV1 at 6 and 10, 10 and 14, or 6, 10, and 14 weeks of age. The primary objective was to compare antirotavirus immunoglobulin A (IgA) seroconversion at 18 weeks in the 6/10/14 arm to the cumulative seroconversion (highest result at 14 or 18 weeks) in the 6/10 arm. Overall, 480 (76.2%) of 630 randomized infants completed the trial per protocol. Seroconversion in the 6/10/14 arm was 36.7% (95% CI, 29.8, 44.2) compared to 36.1% (CI, 29.0, 43.9) in the 6/10 arm, (P=1.0); the result from the 10/14 arm was 38.5% (CI, 31.2, 46.3). Seroconversion in the 6/10 arm at 14 weeks (post hoc) was lower at 29.7% (CI, 23.1, 37.3). In Pakistani infants, the immunogenicity of RV1 did not increase significantly with 3 doses at 6, 10, and 14 weeks compared to ...
Connected graphs with minimum degree δ and at least 2δ + 1 vertices have paths with at least 2δ +... more Connected graphs with minimum degree δ and at least 2δ + 1 vertices have paths with at least 2δ + 1 vertices. We provide a characterization of all such graphs which have no longer paths. Extremal problems involving paths and cycles have been considered since the infancy of graph theory. The question which interests us here is the question of what minimum degree condition guarantees a path of a preassigned length. This question was answered by Erdös and Gallai [4] and again by Andrasfai [1]. Our formulation of their answer is Theorem 1 Let G be a connected graph with minimum degree δ and at least 2δ + 1 vertices. Then G contains a path of at least 2δ + 1 vertices.
Volume 1: Adaptive Control; Advanced Vehicle Propulsion Systems; Aerospace Systems; Autonomous Systems; Battery Modeling; Biochemical Systems; Control Over Networks; Control Systems Design; Cooperativ, 2012
Health management of Li-ion batteries depends on knowledge of certain battery internal dynamics (... more Health management of Li-ion batteries depends on knowledge of certain battery internal dynamics (e.g., lithium consumption and film growth at the solid-electrolyte interface) whose inputs and outputs are not directly measurable with noninvasive methods. This presents a problem of identification of inaccessible subsystems. To address this problem, we apply the retrospective-cost subsystem identification (RCSI) method. As a first step, this paper presents a simulation-based study that assumes as the truth model of the battery an electrochemistrybased battery charge/discharge model of Doyle, Fuller, and Newman, and later augmented with a battery-health model by Ramadass. First, this truth model is used to generate the data needed for the identification study. Next, the film-growth component of the battery-health model is assumed to be unknown, and the identification of this inaccessible subsystem is performed using RCSI. The results show that the subsystem identification method can identify the film growth quite accurately when the chemical reactions leading to film growth are consequential.
With advances in miniaturization, wireless communication, and the theory of selforganizing system... more With advances in miniaturization, wireless communication, and the theory of selforganizing systems, it has become possible to consider scenarios where a very large number of networkable sensors are deployed randomly over an extended environment and organize themselves into a network. Such networks-which we term largescale sensor networks (LSSN's)-can be useful in many situations, including military surveillance, environmental monitoring, disaster relief, etc. The idea is that, by deploying an LSSN, an extended environment can be rendered observable for an external user (e.g., a monitoring station) or for users within the system (e.g., persons walking around with palm-sized devices). Unlike custom-designed networks, these randomly deployed networks need no pre-design and configure themselves through a process of self-organization. The sensor nodes themselves are typically anonymous, and information is addressed by location or attribute rather than by node ID. This approach provides several advantages, including: 1) Scalability; 2) Robustness; 3) Flexibility; 4) Expandability; and 5) Versatility. Indeed, this abstraction is implicit in such ideas as smart paint, smart dust, and smart matter. The purpose of our research is to explore how a system comprising a very large number of randomly distributed nodes can organize itself to communicate information between designated geographical locations. To keep the system realistic, we assume that each node has only limited reliability, energy resources, wireless communication capabilities, and computational capacity. Thus, direct long-range communication between nodes is not possible, and most messaging involves a large number of "hops" between neighboring nodes. In particular, we are interested in obtaining reliable communication at the system level from simple, unreliable nodes.
Proceedings of the 2011 American Control Conference, 2011
We present a growing-window variableregularization recursive least squares (GW-VR-RLS) algorithm.... more We present a growing-window variableregularization recursive least squares (GW-VR-RLS) algorithm. Standard recursive least squares (RLS) uses a time-invariant regularization. More specifically, the inverse of the initial covariance matrix in classical RLS can be viewed as a regularization term, which weights the difference between the next state estimate and the initial state estimate. The present paper allows for time-varying in the weighting as well as what is being weighted. This extension can be used to modulate the speed of convergence of the estimates versus the magnitude of transient estimation errors. Furthermore, the regularization term can weight the difference between the next state estimate and a time-varying vector of parameters rather than the initial state estimate as is required in standard RLS.
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Papers by Asad Ali