Thermal annealing behaviour on electrical properties of Pd/Ru Schottky contacts on n-type GaN

We have investigated the electrical properties of Pd/Ru Schottky contacts on n-GaN as a function of annealing temperature by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The Schottky barrier height of the as-deposited Pd/Ru contact is found to be 0.67 eV (I-V) and 0.79 eV (C-V), respectively. Measurements showed that the Schottky barrier height increased from 0.68 eV (I-V) and 0.80 eV (C-V) to 0.80 eV (I-V) and 0.96 eV (C-V) as the annealing temperature is varied from 200 °C to 300 °C. Upon annealing at 400 °C and 500 °C, the Schottky barrier height decreased to 0.73 eV (I-V) and 0.85 eV (C-V) and 0.72 eV (I-V) and 0.84 eV (C-V), respectively. It is noted that the barrier height further decreased to 0.59 eV (I-V) and 0.72 eV (C-V) when the contact is annealed at 600 °C. The change of Schottky barrier heights and ideality factors with annealing temperature may be due to the formation of interfacial compounds at the Ru/Pd/n-GaN interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2788

Role of LTACH in Chronic Critical Illness in the Elderly

Long-term acute care hospitals (LTACH) have become an integral part of the health care continuum since they were established in the USA in 1999. Many elderly patients admitted to intensive care units (ICUs) survive an acute episode of illness but do not recover fully and develop chronic critical illness (CCI). These patients have been stabilized in short-term acute care hospitals with completion of diagnostic workup and transferred to LTACHs. Elderly patients who have CCI form an important group of patients admitted to LTACHs. LTACHs are organized to provide multidisciplinary management that includes complex medical therapies such as ventilator weaning and dialysis, intravenous therapies like total parental nutrition, complex wound care and rehabilitative services, including physical, occupational and speech therapies. Consistent with high disease burden of comorbidities and poor outcome in the subset of patients with CCI, palliative care should become an essential component of the post-acute care continuum (PACC). LTACHs play a pivotal role in transitioning these patients across the PACC. Details regarding the organization of LTACHs, management of patients with special reference to CCI and perspectives for future advances are discussed in this chapter

Adaptation of the human nervous system for self-aware secure mobile and IoT systems

IT systems have been deployed across several domains, such as hospitals and industries, for the management of information and operations. These systems will soon be ubiquitous in every field due to the transition towards the Internet of Things (IoT). The IoT brings devices with sensory functions into IT systems through the process of internetworking. The sensory functions of IoT enable them to generate and process information automatically, either without human contribution or having the least human interaction possible aside from the information and operations management tasks. Security is crucial as it prevents system exploitation. Security has been employed after system implementation, and has rarely been considered as a part of the system. In this dissertation, a novel solution based on a biological approach is presented to embed security as an inalienable part of the system. The proposed solution, in the form of a prototype of the system, is based on the functions of the human nervous system (HNS) in protecting its host from the impacts caused by external or internal changes. The contributions of this work are the derivation of a new system architecture from HNS functionalities and experiments that prove the implementation feasibility and efficiency of the proposed HNS-based architecture through prototype development and evaluation. The first contribution of this work is the adaptation of human nervous system functions to propose a new architecture for IT systems security. The major organs and functions of the HNS are investigated and critical areas are identified for the adaptation process. Several individual system components with similar functions to the HNS are created and grouped to form individual subsystems. The relationship between these components is established in a similar way as in the HNS, resulting in a new system architecture that includes security as a core component. The adapted HNS-based system architecture is employed in two the experiments prove its implementation capability, enhancement of security, and overall system operations. The second contribution is the implementation of the proposed HNS-based security solution in the IoT test-bed. A temperature-monitoring application with an intrusion detection system (IDS) based on the proposed HNS architecture is implemented as part of the test-bed experiment. Contiki OS is used for implementation, and the 6LoWPAN stack is modified during the development process. The application, together with the IDS, has a brain subsystem (BrSS), a spinal cord subsystem (SCSS), and other functions similar to the HNS whose names are changed. The HNS functions are shared between an edge router and resource-constrained devices (RCDs) during implementation. The experiment is evaluated in both test-bed and simulation environments. Zolertia Z1 nodes are used to form a 6LoWPAN network, and an edge router is created by combining Pandaboard and Z1 node for a test-bed setup. Two networks with different numbers of sensor nodes are used as simulation environments in the Cooja simulator. The third contribution of this dissertation is the implementation of the proposed HNS-based architecture in the mobile platform. In this phase, the Android operating system (OS) is selected for experimentation, and the proposed HNS-based architecture is specifically tailored for Android. A context-based dynamically reconfigurable access control system (CoDRA) is developed based on the principles of the refined HNS architecture. CoDRA is implemented through customization of Android OS and evaluated under real-time usage conditions in test-bed environments. During the evaluation, the implemented prototype mimicked the nature of the HNS in securing the application under threat with negligible resource requirements and solved the problems in existing approaches by embedding security within the system. Furthermore, the results of the experiments highlighted the retention of HNS functions after refinement for different IT application areas, especially the IoT, due to its resource-constrained nature, and the implementable capability of our proposed HNS architecture.--- IT-järjestelmiä hyödynnetään tiedon ja toimintojen hallinnassa useilla aloilla, kuten sairaaloissa ja teollisuudessa. Siirtyminen kohti esineiden Internetiä (Internet of Things, IoT) tuo tällaiset laitteet yhä kiinteämmäksi osaksi jokapäiväistä elämää. IT-järjestelmiin liitettyjen IoT-laitteiden sensoritoiminnot mahdollistavat tiedon automaattisen havainnoinnin ja käsittelyn osana suurempaa järjestelmää jopa täysin ilman ihmisen myötävaikutusta, poislukien mahdolliset ylläpito- ja hallintatoimenpiteet. Turvallisuus on ratkaisevan tärkeää IT-järjestelmien luvattoman käytön estämiseksi. Valitettavan usein järjestelmäsuunnittelussa turvallisuus ei ole osana ydinsuunnitteluprosessia, vaan otetaan huomioon vasta käyttöönoton jälkeen. Tässä väitöskirjassa esitellään uudenlainen biologiseen lähestymistapaan perustuva ratkaisu, jolla turvallisuus voidaan sisällyttää erottamattomaksi osaksi järjestelmää. Ehdotettu prototyyppiratkaisu perustuu ihmisen hermoston toimintaan tilanteessa, jossa se suojelee isäntäänsä ulkoisten tai sisäisten muutosten vaikutuksilta. Tämän työn keskeiset tulokset ovat uuden järjestelmäarkkitehtuurin johtaminen ihmisen hermoston toimintaperiaatteesta sekä tällaisen järjestelmän toteutettavuuden ja tehokkuuden arviointi kokeellisen prototyypin kehittämisen ja toiminnan arvioinnin avulla. Tämän väitöskirjan ensimmäinen kontribuutio on ihmisen hermoston toimintoihin perustuva IT-järjestelmäarkkitehtuuri. Tutkimuksessa arvioidaan ihmisen hermoston toimintaa ja tunnistetaan keskeiset toiminnot ja toiminnallisuudet, jotka mall-innetaan osaksi kehitettävää järjestelmää luomalla näitä vastaavat järjestelmäkomponentit. Nä-istä kootaan toiminnallisuudeltaan hermostoa vastaavat osajärjestelmät, joiden keskinäinen toiminta mallintaa ihmisen hermoston toimintaa. Näin luodaan arkkitehtuuri, jonka keskeisenä komponenttina on turvallisuus. Tämän pohjalta toteutetaan kaksi prototyyppijärjestelmää, joiden avulla arvioidaan arkkitehtuurin toteutuskelpoisuutta, turvallisuutta sekä toimintakykyä. Toinen kontribuutio on esitetyn hermostopohjaisen turvallisuusratkaisun toteuttaminen IoT-testialustalla. Kehitettyyn arkkitehtuuriin perustuva ja tunkeutumisen estojärjestelmän (intrusion detection system, IDS) sisältävä lämpötilan seurantasovellus toteutetaan käyttäen Contiki OS -käytöjärjestelmää. 6LoWPAN protokollapinoa muokataan tarpeen mukaan kehitysprosessin aikana. IDS:n lisäksi sovellukseen kuuluu aivo-osajärjestelmä (Brain subsystem, BrSS), selkäydinosajärjestelmä (Spinal cord subsystem, SCSS), sekä muita hermoston kaltaisia toimintoja. Nämä toiminnot jaetaan reunareitittimen ja resurssirajoitteisten laitteiden kesken. Tuloksia arvioidaan sekä simulaatioiden että testialustan tulosten perusteella. Testialustaa varten 6LoWPAN verkon toteutukseen valittiin Zolertia Z1 ja reunareititin on toteutettu Pandaboardin ja Z1:n yhdistelmällä. Cooja-simulaattorissa käytettiin mallinnukseen ymp-äristönä kahta erillistä ja erikokoisuta sensoriverkkoa. Kolmas tämän väitöskirjan kontribuutio on kehitetyn hermostopohjaisen arkkitehtuurin toteuttaminen mobiilialustassa. Toteutuksen alustaksi valitaan Android-käyttöjärjestelmä, ja kehitetty arkkitehtuuri räätälöidään Androidille. Tuloksena on kontekstipohjainen dynaamisesti uudelleen konfiguroitava pääsynvalvontajärjestelmä (context-based dynamically reconfigurable access control system, CoDRA). CoDRA toteutetaan mukauttamalla Androidin käyttöjärjestelmää ja toteutuksen toimivuutta arvioidaan reaaliaikaisissa käyttöolosuhteissa testialustaympäristöissä. Toteutusta arvioitaessa havaittiin, että kehitetty prototyyppi jäljitteli ihmishermoston toimintaa kohdesovelluksen suojaamisessa, suoriutui tehtävästään vähäisillä resurssivaatimuksilla ja onnistui sisällyttämään turvallisuuden järjestelmän ydintoimintoihin. Tulokset osoittivat, että tämän tyyppinen järjestelmä on toteutettavissa sekä sen, että järjestelmän hermostonkaltainen toiminnallisuus säilyy siirryttäessä sovellusalueelta toiselle, erityisesti resursseiltaan rajoittuneissa IoT-järjestelmissä

Shopping as Experience and Website as a Social Actor: Web Interface Design and Para-Social Presence

We make a case for treating a Web site as a social actor and propose para-social presence as a central construct to measure the structure of the relationship that evolves between a web site and its visitors. Para- social presence (PSP) captures the underlying psychological cues that measure the level and extent of interaction among participating social entities (in an online shopping context in this study). We also argue that one medium could possess different levels of PSP, depending on how it is configured and used. The first phase of our research conceptualizes and develops an instrument to measure PSP. The second phase investigates the impact of new technologies and associated web interface design decisions on perceived communication characteristics of a medium, PSP and subsequent user evaluations of the web site. Specifically, this research studies the impact of personalization technologies and support for virtual communities

FORMULATION, OPTIMIZATION AND IN VITRO EVALUATION OF GASTRORETENTIVE MUCOADHESIVE MICROSPHERES OF FUROSEMIDE

Objective: The objective of this study was to formulate and evaluate sustained release gastro retentive microspheres of furosemide using mucoadhesive polymers. It was expected that gastro retention plus mucoadhesion would contribute to extending the rate of drug release in the acidic medium in vitro, thereby projecting this formulation as a potential candidate for improvement of oral bioavailability of furosemide.Methods: Mucoadhesive microspheres of furosemide were formulated by ionic gelation method by using two opposite charge mucoadhesive polymers (cationic chitosan and anionic sodium alginate). The formulations were optimized by employing 22 factorial design and characterized for in vitro evaluation i.e. drug entrapment efficiency, mucoadhesion study, drug release study, swelling study, etc.Results: The microspheres formed were spherical in shape, and size ranged between 692-815 µm. Drug entrapment efficiency, % mucoadhesion and % drug release were ranged between 74.82-84.21 %, 22-43 % and 85.01-94.21 % respectively. DSC analysis revealed that there was no incompatibility between drug and excipients. The mechanism of drug release from microspheres followed Hixson-Crowell model. Comparison of drug release with marketed formulation (Lasix-40®) demonstrated the sustained release pattern of the gastro retentive mucoadhesive microspheres of Furosemide.Conclusion: This work suggests that gastro retentive mucoadhesive microspheres, an effective drug delivery system for furosemide in improving the bioavailability of the drug.Keywords: Furosemide, Mucoadhesive microsphere, Factorial design, Drug entrapment efficiency, Bioavailabilit

The Citizen Participation Continuum: Where does the US Stand?

Active citizen participation facilitated by information technology can have profound implications for democracy and civic discourse. In this paper we describe a continuum of tools that encourage active participation by citizens. We use a comprehensive review of the web-sites of the 50 States of the U.S. to chart the current position of the country on this continuum. We find that these G2C initiatives provide some tools for passive citizen participation (e.g. on-line feedback) but ignore two important tools for active citizen participation (electronic voting and discussion forums). The lack of discussion forums is especially surprising since they are a low cost scalable tool for fostering deliberation and works equally well under both representational and direct democracy systems. In conclusion, the paper discusses the future implications of the participation continuum

Ant Colony Optimization. A Computational Intelligence Technique

Ant colony optimization (ACO) is a novel computational technique inspired by a foraging behavior of ants has been successfully applied for solving real world optimization problems. This behavioral pattern inspires artificial ants for the search of solutions to the various types of optimization problems. ACO is a probabilistic search approach founded on the idea of evolutionary process. In this paper, we present an overview of ant colony optimization and ACO variants up to now. we also summarize various types of applications. Finally we focus on some research efforts directed at receiving a dipper understanding of the ant colony optimization algorithms