An analysis of approximate controllability for Hilfer fractional delay differential equations of Sobolev type without uniqueness

This study focused on the approximate controllability results for the Hilfer fractional delay evolution equations of the Sobolev type without uniqueness. Initially, the Lipschitz condition is derived from the hypothesis, which is represented by a measure of noncompactness, in particular, nonlinearity. We also examined the continuity of the solution map of the Sobolev type of Hilfer fractional delay evolution equation and the topological structure of the solution set. Furthermore, we prove the approximate controllability of the fractional evolution equation of the Sobolev type with delay. Finally, we provided an example to illustrate the theoretical results

Using In Situ Liquid Single Photon Ionization Mass Spectrometry (SPI-MS) to Probe Lithium Polysulfide Electrolyte in Motion

The solid-liquid (s-l) interface is the most common interface encountered in electrochemical systems. The s-l interface has wide applications in energy storage, catalysis, and material sciences. In situ studies of chemical reactions taking place on the s-l interfaces can further our understanding of electron transfer and link to real-world device functions under challenging conditions. Direct probing of the solid electrode and liquid electrolyte interface has been realized using a vacuum compatible electrochemical microfluidic reactor, system for analysis at the liquid vacuum interface (SALVI) with time-of-flight secondary ion mass spectrometry (ToF-SIMS). Most recently, the electrochemical version of SALVI was integrated to the synchrotron based single photon ionization mass spectrometry (SPI-MS). SPI-MS has proven to be a versatile technique for analysis of organic species in the solid or gas phase due to its nature of soft ionization. As a practical example, three different lithium polysulfide electrolytes, Li2S4, Li2S6, and Li2S8, were studied under dynamic conditions with various applied voltages. It was found that despite some PDMS interference peaks such as 369 m/z, unique peaks of interest signifying the electron transfer of the LixSy electrolytes can be identified according to the SPI-MS mass spectra. The observation of in situ compositional changes as a result of electrochemical reaction that take place at the s-l interface in a three electrode system allowed us to piece all the fragments together and identify the compound present in the sample at different stages of photoionization energy (PIE) values. Moreover, we demonstrate that liquid SPI-MS technique has been enabled to study dynamic electron transfer of LixSy electrolytes using real-time molecular imaging

Spatially Constrained Organic Diquat Anolyte for Stable Aqueous Flow Batteries

Redox-active organic materials (ROMs) are becoming increasingly attractive for use in redox flow batteries as promising alternatives to traditional inorganic counterparts. However, the reported ROMs are often accompanied by challenges, including poor solubility and stability. Herein, we demonstrate that the commonly used diquat herbicides, with solubilities of >2 M in aqueous electrolytes, can be used as stable anolyte materials in organic flow batteries. When coupled with a ferrocene-derived catholyte, the flow cells with the diquat anolyte demonstrate long galvanic cycling with high capacity retention. Notably, the mechanistic underpinnings of this remarkable stability are attributed to the improved π-conjugation that originated from the near-planar molecular conformations of the spatially constrained 2,2′-bipyridyl rings, suggesting a viable structural engineering strategy for designing stable organic materials

Optimal control results for impulsive fractional delay integrodifferential equations of order 1 < r < 2 via sectorial operator

This research investigates the existence of nonlocal impulsive fractional integrodifferential equations of order 1 < r < 2 with infinite delay. To begin with, we discuss the existence of a mild solution for the fractional derivatives by using the sectorial operators, the nonlinear alternative of the Leray–Schauder fixed point theorem, mixed Volterra–Fredholm integrodifferential types, and impulsive systems. Furthermore, we develop the optimal control results for the given system. The application of our findings is demonstrated with the help of an example

Stacked Cu1.8S nanoplatelets as counter electrode for quantum dot-sensitized solar cell

It is found that the electrocatalytic activity of Cu2-xS thin films used in quantum dot-sensitized solar cells (QDSSCs) as counter electrode (CE) for the reduction of polysulfide electrolyte depends on the surface active sulfide and disulfide species and the deficiency of Cu. The preferential bonding between Cu2+ and S2-, leading to the selective formation of a Cu1.8S stacked platelet-like morphology, is determined by the cetyl trimethyl ammonium bromide surfactant and deposition temperature; the crab-like Cu-S coordination bond formed dictates the surface area to volume ratio of the Cu1.8S thin films and their electrocatalytic activity. The Cu deficiency enhances the conductivity of the Cu1.8S thin films, which exhibit near-infrared localized surface plasmon resonance due to free carriers, and UV-vis absorption spectra show an excitonic effect due to the quantum size effect. When these Cu1.8S thin films were employed as CEs in QDSSCs, a robust photoconversion efficiency of 5.2% was obtained for the film deposited at 60 °C by a single-step chemical bath deposition method

Completed suicides and self-harm in Malaysia: A systematic review

Objective: Most of the research into suicide and self-harm has been conducted in the United States and Europe, yet the volume of research does not reflect the distribution of suicide globally, with Asia accounting for up to 60% of all suicides. The present study systematically reviews the literature to assess the prevalence and correlates of suicidal acts in Malaysia in Southeast Asia. Methods: Five relevant databases were searched from inception up to February 2014, and a narrative synthesis of the results from the included studies was performed. Studies were eligible for inclusion if they were correlational survey research and archival/observational research describing self-harm and suicide. Outcomes included completed suicides and self-harm including suicide attempts and self-poisoning, suicide plans and suicidal ideation. Results: In total, 39 studies met the inclusion criteria. The principal findings were that the prevalence of suicide in Malaysia is approximately 6-8 per 100,000 population per year and that there is an excess of suicide among men, people younger than 40 years and the Indian minority group. The past-month prevalence rates of suicidal ideation, plans and attempts are 1.7, 0.9% and 0.5%, respectively, whereas the past-year prevalence rates of suicidal ideation range between 6% and 8%. Conclusions: The present research marks a first step towards understanding the prevalence and correlates of suicide and self-harm in Malaysia. However, the heterogeneity of the included studies was high. Further research into the antecedents, consequences and interventions for suicide and self-harm in the Malaysian context is required

Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015 : a systematic analysis for the Global Burden of Disease Study 2015

Background Improving survival and extending the longevity of life for all populations requires timely, robust evidence on local mortality levels and trends. The Global Burden of Disease 2015 Study (GBD 2015) provides a comprehensive assessment of all-cause and cause-specific mortality for 249 causes in 195 countries and territories from 1980 to 2015. These results informed an in-depth investigation of observed and expected mortality patterns based on sociodemographic measures. Methods We estimated all-cause mortality by age, sex, geography, and year using an improved analytical approach originally developed for GBD 2013 and GBD 2010. Improvements included refinements to the estimation of child and adult mortality and corresponding uncertainty, parameter selection for under-5 mortality synthesis by spatiotemporal Gaussian process regression, and sibling history data processing. We also expanded the database of vital registration, survey, and census data to 14 294 geography-year datapoints. For GBD 2015, eight causes, including Ebola virus disease, were added to the previous GBD cause list for mortality. We used six modelling approaches to assess cause-specific mortality, with the Cause of Death Ensemble Model (CODEm) generating estimates for most causes. We used a series of novel analyses to systematically quantify the drivers of trends in mortality across geographies. First, we assessed observed and expected levels and trends of cause-specific mortality as they relate to the Socio-demographic Index (SDI), a summary indicator derived from measures of income per capita, educational attainment, and fertility. Second, we examined factors affecting total mortality patterns through a series of counterfactual scenarios, testing the magnitude by which population growth, population age structures, and epidemiological changes contributed to shifts in mortality. Finally, we attributed changes in life expectancy to changes in cause of death. We documented each step of the GBD 2015 estimation processes, as well as data sources, in accordance with Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER). Findings Globally, life expectancy from birth increased from 61.7 years (95% uncertainty interval 61.4-61.9) in 1980 to 71.8 years (71.5-72.2) in 2015. Several countries in sub-Saharan Africa had very large gains in life expectancy from 2005 to 2015, rebounding from an era of exceedingly high loss of life due to HIV/AIDS. At the same time, many geographies saw life expectancy stagnate or decline, particularly for men and in countries with rising mortality from war or interpersonal violence. From 2005 to 2015, male life expectancy in Syria dropped by 11.3 years (3.7-17.4), to 62.6 years (56.5-70.2). Total deaths increased by 4.1% (2.6-5.6) from 2005 to 2015, rising to 55.8 million (54.9 million to 56.6 million) in 2015, but age-standardised death rates fell by 17.0% (15.8-18.1) during this time, underscoring changes in population growth and shifts in global age structures. The result was similar for non-communicable diseases (NCDs), with total deaths from these causes increasing by 14.1% (12.6-16.0) to 39.8 million (39.2 million to 40.5 million) in 2015, whereas age-standardised rates decreased by 13.1% (11.9-14.3). Globally, this mortality pattern emerged for several NCDs, including several types of cancer, ischaemic heart disease, cirrhosis, and Alzheimer's disease and other dementias. By contrast, both total deaths and age-standardised death rates due to communicable, maternal, neonatal, and nutritional conditions significantly declined from 2005 to 2015, gains largely attributable to decreases in mortality rates due to HIV/AIDS (42.1%, 39.1-44.6), malaria (43.1%, 34.7-51.8), neonatal preterm birth complications (29.8%, 24.8-34.9), and maternal disorders (29.1%, 19.3-37.1). Progress was slower for several causes, such as lower respiratory infections and nutritional deficiencies, whereas deaths increased for others, including dengue and drug use disorders. Age-standardised death rates due to injuries significantly declined from 2005 to 2015, yet interpersonal violence and war claimed increasingly more lives in some regions, particularly in the Middle East. In 2015, rotaviral enteritis (rotavirus) was the leading cause of under-5 deaths due to diarrhoea (146 000 deaths, 118 000-183 000) and pneumococcal pneumonia was the leading cause of under-5 deaths due to lower respiratory infections (393 000 deaths, 228 000-532 000), although pathogen-specific mortality varied by region. Globally, the effects of population growth, ageing, and changes in age-standardised death rates substantially differed by cause. Our analyses on the expected associations between cause-specific mortality and SDI show the regular shifts in cause of death composition and population age structure with rising SDI. Country patterns of premature mortality (measured as years of life lost [YLLs]) and how they differ from the level expected on the basis of SDI alone revealed distinct but highly heterogeneous patterns by region and country or territory. Ischaemic heart disease, stroke, and diabetes were among the leading causes of YLLs in most regions, but in many cases, intraregional results sharply diverged for ratios of observed and expected YLLs based on SDI. Communicable, maternal, neonatal, and nutritional diseases caused the most YLLs throughout sub-Saharan Africa, with observed YLLs far exceeding expected YLLs for countries in which malaria or HIV/AIDS remained the leading causes of early death. Interpretation At the global scale, age-specific mortality has steadily improved over the past 35 years; this pattern of general progress continued in the past decade. Progress has been faster in most countries than expected on the basis of development measured by the SDI. Against this background of progress, some countries have seen falls in life expectancy, and age-standardised death rates for some causes are increasing. Despite progress in reducing age-standardised death rates, population growth and ageing mean that the number of deaths from most non-communicable causes are increasing in most countries, putting increased demands on health systems. Copyright (C) The Author(s). Published by Elsevier Ltd.Peer reviewe

An Investigation on the Optimal Control for Hilfer Fractional Neutral Stochastic Integrodifferential Systems with Infinite Delay

The main concern of this manuscript is to study the optimal control problem for Hilfer fractional neutral stochastic integrodifferential systems with infinite delay. Initially, we establish the existence of mild solutions for the Hilfer fractional stochastic integrodifferential system with infinite delay via applying fractional calculus, semigroups, stochastic analysis techniques, and the Banach fixed point theorem. In addition, we establish the existence of mild solutions of the Hilfer fractional neutral stochastic delay integrodifferential system. Further, we investigate the existence of optimal pairs for the Hilfer fractional neutral stochastic delay integrodifferential systems. We provide an illustration to clarify our results

Contact edge roughness in euv lithography: metrology and process evaluation

155 σ.Τα αυξημένα στοχαστικά φαινόμενα στις νανοκατασκευαστικές διεργασίες έχουν ως αποτέλεσμα αποκλίσεις των νανοδομών από το προβλεπόμενο σχήμα τους στο σχέδιο και την ομοιομορφία των διαστάσεών τους. Στην από πάνω προς το κάτω προσέγγιση της νανοτεχνολογίας (λιθογραφικές τεχνικές) τα φαινόμενα αυτά εκδηλώνονται κυρίως στην πλευρική τραχύτητα και στη διασπορά των διαστάσεών των νανοδομών. Ιδιαίτερα στη λιθογραφία της ακραία υπεριώδους ακτινοβολίας (Extreme Ultraviolet Lithography, EUVL) τα δύο αυτά προβλήματα είναι έντονα και αποτελούν δύο από τα θέματα που πρέπει να διευθετηθούν για να χρησιμοποιηθεί η EUVL στη γραμμή παραγωγής ολοκληρωμένων κυκλωμάτων με μικρότερη διάσταση <20nm τα επόμενα χρόνια. Για να γίνει αυτό, ωστόσο, απαιτείται η ανάπτυξη εργαλείων μετρολογίας και προτυποποίησης για την καλύτερη αξιολόγηγη και κατανόηση των διεργασίων και υλικών που εμπλέκονται σε αυτή. Σε αυτή τη διατριβή αναπτύξαμε και εφαρμόσαμε μεθοδολογίες για τη μετρολογία και την προτυποποίηση της τραχύτητας και της ανομοιομορφίας της διάστασης οπών επαφής. Οι οπές επαφής που εξετάσαμε έχουν κατασκευαστεί με EUVL και θα χρησιμοποιηθούν στα ηλεκτρόδια των τρανζίστορ νέας γενιάς. Η μετρολογική προσέγγισή μας βασίζεται στην ανάλυση εικόνων κάτοψης μικροσκοπίου σάρωσης ηλεκτρονικής δέσμης ενώ η προτυποποίηση στοχεύει να συμπεριλάβει τα φαινόμενα του θορύβου πρόσπτωσης των φωτονίων (ΡSN), τη διάχυση των παραγόμενων οξέων και τις παραμέτρους σχεδιασμού των οπών (διάμετρος και μεταξύ τους απόσταση). Στη συνέχεια, εφαρμόσαμε αυτά τα εργαλεία στην ανάλυση και ερμηνεία των πειραματικών αποτελεσμάτων που αφορούν την επίδραση της δόσης ακτινοβολίας του φωτοπολυμερούς και των πρόσθετων συστατικών του (φωτοπαραγωγικού οξέος (PhotoAcid Generator, PAG) και ευαισθητοποιητή) στην πλευρική τραχύτητα των οπών και στη διασπορά των διαστάσεών τους. Βρήκαμε ότι οι εξαρτήσεις της διασποράς των διαστάσεων των οπών από τη δόση και τον ευαισθητοποιητή κυριαρχούνται από τα φαινόμενα PSN ενώ όταν αυξάνεται η συγκέντρωση των μορίων του PAG παρατηρούμε μετάβαση από την περιοχή που κυριαρχεί η στοχαστικότητα λόγω των τυχαίων θέσεων των PAGs στην περιοχή που κεντρικό ρόλο παίζουν τα φαινόμενα PSN . Οι παράμετροι πλευρικής τραχύτητας που υπολογίσαμε (τυπική απόκλιση από την κυκλικότητα και μήκος συσχέτισης των ακμών των οπών) από την ανάλυση όλων των πειραμάτων που πραγματοποίηθηκαν με διαφορετικές συνθέσεις του φωτοπολυμερούς και διαφορετικές δόσεις ακτινοβόλησης δείχνουν ότι αυτές συγχωνεύονται σε μία κοινή αυξητική καμπύλη όταν τοποθετηθούν σε διάγραμμα συναρτήσει της μέσης διαμέτρου των οπών. Επιπροσθέτως, η τυπική απόκλιση της πλευρικής τραχύτητας των οπών αυξάνει με τη δόση και τη συγκέντρωση του PAG, σε αντίθεση με ό,τι συμβαίνει στις γραμμικές δομές. Η ερμηνεία των παραπάνω πειραματικών ευρημάτων μπορεί να βοηθηθεί από την ανάλυση με φάσματα ισχύος της τραχύτητας των ακμών των οπών. Σε αυτά φαίνεται η κυρίαρχη συμμετοχή των χαμηλών συχνοτήτων στη διαμόρφωση της πλευρικής τραχύτητας η οποία μπορεί να αποδοθεί σε αυξημένη αλληλεπίδραση μεταξύ γειτονικών οπών ιδίως στις κατευθύνσεις που οι ακμές τους πλησιάζουν περισσότερο. Συνοψίζοντας, στη διατριβή αυτή δείχθηκε ότι στις νανολιθογραφικές τεχνικές όπως η EUVL, πέρα από τα φαινόμενα θορύβου λόγω τυχαίας πρόπτωσης των φωτονίων, η τραχύτητα και η διασπορά των διαστάσεων μπορεί να επηρεάζεται από την τυχαία θέσει των πρόσθετων μορίων στο φωτοπολυμερές αλλά και από την αλληλεπίδραση μεταξύ των γειτονικών οπών σε συγκεκριμένες διευθύνσεις, η οποία καθορίζεται από τη διάμετρό της και τη μεταξύ τους απόσταση.The increased stochastic effects in the nanofabrication processes result in patterned features with deviations from the designed shape and size uniformity. In the top-down approach to nanotechnology (lithographic techniques), the process stochasticity is manifested in the roughness of the feature surfaces and the variability of their size. The roughness and variability issues become more evident in Extreme Ultra Violet Lithography, the strongest candidate for circuit manufacturing at critical dimensions <20nm. The fabrication of nanofeatures with controlled sidewall roughness and variability using EUVL requires the development of advanced metrological and modelling tools since the capabilities of the present methods are limited. In this thesis, we developed metrology and modelling methodologies specialized in the measurement of the roughness and variability of contact holes and the simulation of their fabrication. The metrology approach is based on the analysis of top-down SEM images, while a simple modelling framework is used capable to include the effects of photon shot noise (PSN) acid diffusion and pattern parameters (CD and pitch). Then we applied these tools in the analysis and interpretation of experimental results concerning the effects of exposure dose and resist ingredients (PAG, sensitizer, quencher) on contact sidewall roughness (Contact Edge Roughness, CER) and size variability (Critical Dimension Uniformity, CDU). We found that the dependencies of CDU on dose, sensitizer and quencher are dominated by photon shot noise (PSN) effects whereas a transition from PAG statistics dominated to PSN driven behavior is observed in the dependence of CDU on PAG concentration. The estimated CER parameters (root mean square (RMS) value and correlation length (ξ) exhibit a merging trend when are plotted against the final critical dimension (CD). In addition, RMS value increases with exposure dose and PAG loading contrary to shot noise and Line Edge Roughness expectations. Power spectrum analysis reveals the dominant contribution of low-frequency undulations to CER, which is attributed to the enhanced interaction along specific directions between the aerial image and / or acid kinetics of nearby contacts. This inter-contact effect is further intensified with CD for fixed pitch and may explain the observed CER behavior. In summary, the results of this thesis show that in EUV lithography, besides PSN effects the roughness and variability of the printed features may also be affected by the chemical noise of PAG molecules and the pattern parameters CD and pitch.VIJAYAKUMAR MURUGESAN KUPPUSWAM