An area-optimized N-bit multiplication technique using N/2-bit multiplication algorithm

A unique design for an optimized N-bit multiplier is proposed and implemented which utilizes a modified divide-and-conquer technique. The conventional technique requires four N/2-bit multipliers to perform N-bit multiplication, whereas the proposed design uses only one multiplier module in hardware to perform the functionality of four modules. It uses Dadda algorithm in its multiplier module. It has been implemented using Verilog HDL, and a good accuracy of results was observed in simulations which effectively verify its functionality. Design was also synthesized on various FPGAs including Spartan 3E, Virtex-5 and Virtex-7. Performance summary, after place and route, showed that the proposed approach significantly reduces hardware utilization. Furthermore, the proposed design is almost 75% more efficient in terms of resources utilization and operating frequency as compared to the conventional design

Association Of Maternal Age And Hemoglobin Level With Apgar Score Of Newborns In A Tertiary Care Hospital Of Suburbs Of Islamabad

Objectives: To determine the association of Apgar score with maternal age and hemoglobin. Methods A cross-sectional study was conducted on mothers (n=306) delivering live, full-term, singleton babies by spontaneous vertex delivery. Women who suffered stillbirths had babies of unknown gestational age or showed co-morbidities were excluded. SPSS version 26 was used for data analysis. Mean + standard deviation, and percentages were calculated. Cross-tabulation and logistic regression were done to see the association between dependent and independent variables. A p-value of <0.05 was statistically significant. Results The ages of women ranged from 20 to 40 years (mean= 25+1.9).  The number of patients aged 24 years with Hb <7g/dl was 6 (37.5%). Out of all, 90 (29.4%) patients had Hb >11g/dl, and their ages were 30 years which was significant (p = 0.000). Apgar score for the neonates showed that 258 (84.3%) had an Apgar score >7 while 48 (15.7%) had a score < 7. Babies of mothers whose age was 26 years had Apgar score < 7(25%) (p = 0.001). Neonatal birth weight, of <2kg was observed in infants born to young mothers of 26 years of age (20%) (p = 0.001), and a weight >3.5kg was recorded in 20 infants (6.5%). The younger mothers had lower Hb, and their babies had low Apgar scores <7 at the time of birth (p = 0.001). Conclusion Women of younger age and lower hemoglobin levels give birth to infants with low Apgar scores and birth weight. Low birth weight in neonates is significantly associated with a low five-minute Apgar score

Verification of Tether Deployment System aboard CubeSat through Dynamics Simulations and Tests

This paper proposes a proper model selection strategies for the dynamic simulations of the tether deployment mission aboard a CubeSat. Space tether technology will enable innovative space missions in the near future. The Coulomb Drag Propulsion (CDP), including electric solar wind sailing, is one of the plausible future technologies. The authors currently develop a CubeSat, FORESAIL-1, for space demonstration of CDP. However, the analytical simulations for the verification and validation of the mission design typically require a high computational cost. This is because a minimum model order is not selected properly. In this study, through observing a preliminary analytical model for tether deployment analysis, the simplest model is chosen to avoid the mission failure modes in each deployment phase.Peer reviewe

Artificial Intelligence for Cognitive Health Assessment: State-of-the-Art, Open Challenges and Future Directions

The subjectivity and inaccuracy of in-clinic Cognitive Health Assessments (CHA) have led many researchers to explore ways to automate the process to make it more objective and to facilitate the needs of the healthcare industry. Artificial Intelligence (AI) and machine learning (ML) have emerged as the most promising approaches to automate the CHA process. In this paper, we explore the background of CHA and delve into the extensive research recently undertaken in this domain to provide a comprehensive survey of the state-of-the-art. In particular, a careful selection of significant works published in the literature is reviewed to elaborate a range of enabling technologies and AI/ML techniques used for CHA, including conventional supervised and unsupervised machine learning, deep learning, reinforcement learning, natural language processing, and image processing techniques. Furthermore, we provide an overview of various means of data acquisition and the benchmark datasets. Finally, we discuss open issues and challenges in using AI and ML for CHA along with some possible solutions. In summary, this paper presents CHA tools, lists various data acquisition methods for CHA, provides technological advancements, presents the usage of AI for CHA, and open issues, challenges in the CHA domain. We hope this first-of-its-kind survey paper will significantly contribute to identifying research gaps in the complex and rapidly evolving interdisciplinary mental health field

Coulomb drag propulsion experiments of ESTCube-2 and FORESAIL-1

This paper presents two technology experiments – the plasma brake for deorbiting and the electric solar wind sail for interplanetary propulsion – on board the ESTCube-2 and FORESAIL-1 satellites. Since both technologies employ the Coulomb interaction between a charged tether and a plasma flow, they are commonly referred to as Coulomb drag propulsion. The plasma brake operates in the ionosphere, where a negatively charged tether deorbits a satellite. The electric sail operates in the solar wind, where a positively charged tether propels a spacecraft, while an electron emitter removes trapped electrons. Both satellites will be launched in low Earth orbit carrying nearly identical Coulomb drag propulsion experiments, with the main difference being that ESTCube-2 has an electron emitter and it can operate in the positive mode. While solar-wind sailing is not possible in low Earth orbit, ESTCube-2 will space-qualify the components necessary for future electric sail experiments in its authentic environment. The plasma brake can be used on a range of satellite mass classes and orbits. On nanosatellites, the plasma brake is an enabler of deorbiting – a 300-m-long tether fits within half a cubesat unit, and, when charged with -1 kV, can deorbit a 4.5-kg satellite from between a 700- and 500-km altitude in approximately 9–13 months. This paper provides the design and detailed analysis of low-Earth-orbit experiments, as well as the overall mission design of ESTCube-2 and FORESAIL-1.Peer reviewe

Coulomb drag propulsion experiments of ESTCube-2 and FORESAIL-1

This paper presents two technology experiments – the plasma brake for deorbiting and the electric solar wind sail for interplanetary propulsion – on board the ESTCube-2 and FORESAIL-1 satellites. Since both technologies employ the Coulomb interaction between a charged tether and a plasma flow, they are commonly referred to as Coulomb drag propulsion. The plasma brake operates in the ionosphere, where a negatively charged tether deorbits a satellite. The electric sail operates in the solar wind, where a positively charged tether propels a spacecraft, while an electron emitter removes trapped electrons. Both satellites will be launched in low Earth orbit carrying nearly identical Coulomb drag propulsion experiments, with the main difference being that ESTCube-2 has an electron emitter and it can operate in the positive mode. While solar-wind sailing is not possible in low Earth orbit, ESTCube-2 will space-qualify the components necessary for future electric sail experiments in its authentic environment. The plasma brake can be used on a range of satellite mass classes and orbits. On nanosatellites, the plasma brake is an enabler of deorbiting – a 300-m-long tether fits within half a cubesat unit, and, when charged with - 1 kV, can deorbit a 4.5-kg satellite from between a 700- and 500-km altitude in approximately 9–13 months. This paper provides the design and detailed analysis of low-Earth-orbit experiments, as well as the overall mission design of ESTCube-2 and FORESAIL-1.</p

Onboard Communication Systems for Low Cost Small Satellites

The development of a large number of Nano and Pico-satellite missions, with spacecrafts of mass lower than 10 kg and 1 kg respectively, started in the beginning of this century due to the availability of low-cost piggyback launch opportunities. Such small satellites are usually built using commercially available electronic components that are not qualified for the space environment. This approach reduces the total cost of the satellite missions but at the expense of design effort which is needed not to compromise the reliability of the designed spacecrafts. One of the foremost design efforts in this regard is the design re-use method which extends the cost reduction to the system level, and helps in simplifying the development cycle for a space mission. The on-board communication subsystem consist of critical set of elements common to every mission, and therefore is not exempt from such a design philosophy. The on-board networks, on-board transceivers, and the protocols are all critical elements for a spacecraft mission and, at the same time, some of the most specialized and complex ones. Innovative data communication systems are therefore desirable for the future space missions. The size of the satellites keeps reducing as the time progresses, therefore the harness mass and complexity inside the satellite becomes a prime challenge. An innovative approach to smart harness is therefore necessary which reduces the wiring harness for intra-satellite communication. This thesis copes with several problems related to spacecraft subsystem development, integration and testing and proposes some solutions that can help in both keeping system development and production cost low while still achieving good performances. Chapter 1 starts with the design goals of the work and introduction to the Modular Architecture of Small Satellites (AraMiS) project. The biggest design goals of space systems of current era are the cost, time and complexity issues. Modularity and cost-sharing between multiple missions will appear as optimal solutions for reducing development costs, while the use of commercial components (COTS) will be presented as a way to simplify procurement and further lower system cost In Chapter 2, the smart harness approach is proposed which reduces the traditional harness complexities inside the small spacecrafts. The chapter focuses on the design of small spacecrafts which are completely modular and flexible. Modularity at mechanical, electrical and testing level will be discussed in this chapter. Chapter 3 addresses the complete life cycle of a subsystem module i.e. from conception to the final design and testing. The module life cycle uses a variety of Unified Modelling Language (UML) diagrams to fulfill different design stages. Chapter 4 proposes different types of spacecraft configurations based on smart harness approaches including physical module based, satellite on demand and reusable design configurations.A design trade-off is also performed for these configurations. Chapter 6 proposes the design technique of physical module based spacecraft configuration which is based on physical plug and play connectors and logical slots for the subsystem modules. A honeycomb based tile is discussed in this chapter which is used for larger and more demanding spacecraft structures. In Chapter 7, the requirement of data communication across different subsystems of the spacecrafts are described. The use cases have been discussed and the implementation rules have been defined in this Chapter. Chapters 8,9 and 10 focus on module design for intra-satellite communication purposes. The modules have been designed for wired as well as wireless data communication. The wired solution is based on on-board data bus module for inter-tile data communication. Wireless solutions included both optical and radio frequency based solutions. The optical module has been designed for optical free space as well as glass fiber based communication purposes. The comparison between theoretical and practical results has been made. The radio frequency based module is based on commercial module and simpliciTI protocol stack. In Chapter 11, the functional testing of modules, tiles and whole satellites is discussed. The testing scheme of functional test board is also highlighted in this chapter

Analiza zmiany amplitudy z offsetem (AVO) w poziomie złożowym piaskowców kredowych w celu określenia odpowiedzi sejsmicznej na modelowanie zastępowania medium nasycającego (FRM)

Wykorzystanie teorii Gassmana w modelowaniu zastępowania medium nasycającego (fluid replacement modeling – FRM) przestrzeń porową pozwala na stworzenie syntetycznych modeli ośrodka geologicznego o różnym stopniu nasycenia. Metodyka FRM została wykorzystana w skałach zbiornikowych złoża gazu ziemnego Sawan (środkowy basen Indusu, Pakistan) zlokalizowanego w poziomie piaszczystym C kredowej formacji Lower Goru. W badaniach wykorzystano sejsmikę w wersji post-stack oraz dane otworowe (Sawan-01 oraz Sawan-08). Analizę petrofizyczną danych otworowych przeprowadzono w celu wstępnego prognozowania stref nasyconych gazem w lokalizacjach odwiertów, a następnie poprzez dowiązanie danych sejsmicznych do otworowych przeprowadzono predykcję nasycenia dla całego wolumenu sejsmicznego 3D. Analiza zmian amplitudy z offsetem (AVO) w obrębie interwału perspektywicznego prowadzona była dla aktualnego poziomu nasycenia skał zbiornikowych in situ oraz dla modelowanego przypadku zmiany parametrów nasycenia (nasycenie gazem 80%, nasycenie wodą złożową 20%). Parametry elastyczne złoża zostały oszacowane na podstawie wzorów Gassmanna. Odpowiedź AVO dla danych in situ oraz dla danych syntetycznych FRM wskazuje na IV klasę AVO. Obserwowany wzrost amplitudy w funkcji kąta padania dla modeli FRM wykazuje czułość metody AVO na zmianę medium nasycającego przestrzeń porową. Zmiana parametrów złoża związana ze zmianą stopnia nasycenia medium i obserwowaną zmianą w odpowiedzi AVO potwierdza efektywność zastosowanej metody w określaniu litologii i nasycenia skały złożowej. Wykorzystana metodologia pozwoli na dokładniejszą charakterystykę formacji złożowych zarówno w obszarze badań, jak również w innych rejonach świata