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New Contributions Towards Meal and Exercise Announcement-Free Artificial Pancreas SystemsSala Mira, Iván 03 April 2023 (has links)
[ES] Las infusiones exógenas de insulina son vitales para las personas con diabetes tipo 1 para suplir parcialmente la incapacidad del páncreas de secretar insulina. Sin embargo, las terapias intensivas actuales pueden restringir la calidad de vida de los pacientes. Los pacientes con esta enfermedad tienen que tomar decisiones constantemente sobre las dosis de insulina que lleva a la glucosa a niveles seguros. Si no lo consiguen, pueden sufrir las complicaciones crónicas y agudas derivadas de los niveles anormalmente altos o bajos de glucosa. La regulación automática de glucosa con sistemas de páncreas artificial prometía reducir la carga del autocontrol de la enfermedad al mismo tiempo que se mejoraba el tiempo en normoglucemia y se reducía la variabilidad. Sin embargo, estas promesas sólo se han cumplido parcialmente. Aunque esta tecnología mejora el control glucémico que logran las terapias tradicionales, la ingesta de alimentos y la práctica de ejercicio limitan la eficiencia de los sistemas de páncreas artificial durante el día. De hecho, los sistemas comerciales sólo pueden hacerles frente con la ayuda de los pacientes. Para compensar las ingestas, los pacientes deben anunciar el contenido de carbohidratos al sistema. Para el ejercicio, deben anunciar el inicio de la actividad o tomar medidas preventivas como modificar la referencia de glucosa o reducir la basal con mucha antelación. Estas exigencias no sólo no ayudan a reducir la carga del paciente, sino que pueden comprometer la eficiencia del sistema cuando el paciente se equivoca al estimar los carbohidratos, omite el anuncio de la comida o no puede planificar el ejercicio.
Así pues, esta tesis propone nuevos métodos para eliminar el anuncio de ingestas y ejercicio lo que ayudaría a reducir la intervención del paciente en los sistemas de páncreas artificial, y, en consecuencia, mejorar la calidad de vida. Desde un punto de vista de control, las ingestas y el ejercicio pueden considerarse perturbaciones. Esta tesis explota métodos de la literatura de rechazo de perturbaciones y acomodación de fallos para lograr el objetivo de la tesis. En concreto, hay que destacar tres aplicaciones: 1) se ha desarrollado un observador super-twisting para detectar comidas no anunciadas como primer paso para su compensación; 2) se ha diseñado un observador de modos deslizantes de primer orden para la estimación de la ratio de aparición de glucosa, la cual ha sido integrada en un generador de bolos para compensar las comidas; 3) se ha empleado el principio de diseño por modelo interno para mitigar el efecto de las ingestas de alimentos y ejercicio, añadiendo sugerencias de carbohidratos de rescate a la insulina.
Como resultado, las contribuciones de esta tesis allanan el camino para el desarrollo de sistemas de páncreas artificial sin anuncios, que liberen al paciente de la carga de la gestión de la diabetes. / [CA] Les infusions exògenes d'insulina són vitals per a les persones amb diabetis tipus 1 per a suplir parcialment l'incapacitat del pàncrees de secretar insulina. No obstant, les teràpies intensives actuals poden restringir la qualitat de vida dels pacients. Les persones amb aquesta malaltia han de prendre decisions contínuament sobre la dosi d'insulina que fa que la glucosa estiga en valors segurs. Si no ho aconsegueixen, poden sofrir les complicacions cròniques i agudes derivades dels nivells anormalment alts o baixos de glucosa. La regulació automàtica de glucosa amb sistemes de pàncrees artificials prometia reduir la càrrega d'autocontrol de la malaltia al mateix temps que es millorava el temps en normoglucèmia i es reduïa la variabilitat. No obstant, aquestes promeses s'han complit només parcialment. Encara que aquesta tecnologia millora el control de la glucosa, la ingesta d'aliments i la pràctica d'exercici limiten l'eficiència dels sistemes de pàncrees artificials durant el dia. De fet, els sistemes comercials només poden fer-les front amb la ajuda dels pacients. Per a compensar les ingestes, el pacients han d'anunciar al sistema la quantitat de carbohidrats. Per al exercici, han d'anunciar l'inici de l'activitat o prendre mesures preventives com modificar la referència de glucosa o reduir la infusió basal d'insulina. Aquestes exigències no només no ajuden a reduir la càrrega al pacient, sinó que poden comprometre l'eficiència del sistema quan el pacient confon la estimació dels carbohidrats, omet l'anunciament de la ingesta o no pot planificar l'exercici.
Així doncs, aquesta tesi proposa nous mètodes per a eliminar l'anunciament d'ingestes i exercici permetent reduir així la intervenció del pacient, i, en conseqüència, millorar la qualitat de vida. Des del punt de vista de control, les ingestes i el exercici poden considerar-se pertorbacions. Aquesta tesi explota mètodes de la literatura de rebuig de pertorbacions i acomodament de fallades. En particular, es destaquen tres aplicacions: 1) s'ha desenvolupat un observador super-twisting per a detectar ingestes no anunciades com a primer pas per a la seua compensació; 2) se ha dissenyat un observador de modes lliscants per a estimar el rati d'aparició de glucosa de la ingesta, el qual s'ha integrat en un generador de bols d'insulina per compensar les ingestes; 3) se ha empleat el principi de disseny per model intern per a mitigar l'efecte de les ingestes i exercici, incorporant recomanacions de carbohidrats a la insulina.
Com a resultat, les contribucions d'aquesta tesi obren el camí per a desenvolupar sistemes de pàncrees artificial sense anunciaments, que alliberen al pacient de la càrrega de la gestió de la diabetis. / [EN] Exogenous insulin infusions are vital for people with type 1 diabetes to partially make up for the inability of the pancreas to secrete insulin. However, current intensive therapies may restrict patients' quality of life. People with this disease have to constantly make decisions about insulin doses to bring glucose levels to a safe range. If unsuccessful, they may suffer from chronic and acute complications related to abnormally high and low glucose values. The automatic regulation of glucose with artificial pancreas systems promised to reduce patients' self-control burdens while improving time in normoglycemia and decreasing variability. However, these promises are fulfilled only partially. Although this technology outperforms the glycemic outcomes achieved by conventional therapies, meal intake and physical activity limit its daytime performance. Indeed, commercially available systems only can handle them with the support of the patients. For meals, patients must announce the carbohydrate content to the system. For exercise, they must notify the activity or take preventive actions like changing glucose setpoint or decreasing basal well ahead before exercise. These demands do not help reduce the patient's burden. They even can compromise the system performance when the patient misestimates the carbohydrate content, omits the meal announcement, or cannot plan the exercise event.
Hence, this thesis proposes new methods to eliminate the need for meal and exercise announcements, thus reducing patient intervention in artificial pancreas systems for a better quality of life. From a control perspective, meals and exercise can be regarded as disturbances; therefore, this thesis exploits methods from the disturbance rejection and fault accommodation literature to achieve the thesis goal. Specifically, the following three applications must be highlighted: 1) a super-twisting-based residual generator has been developed to detect unannounced meals as the first step to their compensations; 2) a sliding-mode disturbance observer has been designed to estimate the glucose meal appearance, which is fed into a bolusing algorithm to compensate the meals; 3) the internal model principle is employed to mitigate the effects of meal intakes and exercise, supplementing insulin infusions with carbohydrate recommendations.
As a result, the contributions of this thesis pave the way for the development of announcement-free artificial pancreas systems, releasing patients from the burden of diabetes management. / This work was partially supported by: grant DPI2016-78831-C2-1-R funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”;
grant PID2019-107722RB-C21 funded by MCIN/AEI/10.13039/501100011033; and grant ACIF/2017/021 funded by the Generalitat Valenciana through European Social Funds (FSE). Also, the grant BEFPI/2019/077, funded by the Generalitat Valenciana through FSE funds, supported a 7-month research stay at Physiological da University (Óbudai Egyetem, Óbuda, Budapest, Hungary) / Sala Mira, I. (2023). New Contributions Towards Meal and Exercise Announcement-Free Artificial Pancreas Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/192684
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The influence of hypnosis in the context of sports-injuries : an ecosystemic perspectiveKaplan, Roleen Sandra 12 1900 (has links)
In this study an ecosystemic approach to self-hypnosis was utilised as a tool to explore and
describe the healing of sport injuries. Four injured Subjects, from four different sporting
activities participated in the study. Self-hypnosis/hypnosis was used as a linguistic means
to perturb the problem-defining ideas within which the sport injury was embedded. Problem
dis-solution involved a process of reframing each Subject's current reality through dialogue,
and a new reality for each respective Subject was co-constructed through consequent
linguistic differentiation. The hypnotist, participating in the linguistic domain as an equal
participant, looked for intended meanings in each respective conversational exchange with
the athletes, and synthesised information creatively. This process and the thinking behind
each case study is described in detail in this dissertation. / Psychology / M.A. (Psychology)
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Foreign observers in South African elections : an assessment of their contributionsHofmeyr, Jan Hendrik 03 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Over the past three decades the practice of international election observation has
shifted its focus from elections taking place within a decolonialisation context, to
those in independent, but formerly undemocratic, states. The latter accepted the
presence of international observers with some reservation, citing the contention
that observation amounted to an infringement on national sovereignty. The
demise of the former East Block, however, established the primacy of the liberal
democratic ideology in world politics, leaving these states with a limited choice
between democratisation and isolation.
Pro-democracy supporters in former authoritarian countries embraced the
change in ideological climate. Realising the lack of capacity and trust to run
elections by themselves, they generally supported the presence of international
observers in elections of states emerging from prolonged periods of
authoritarianism. Over the past decade this affinity with international missions
has been transformed into skepticism. Three primary reasons for this
disenchantment have been the apparent lack of electoral standards,
uncoordinated observer missions and failure to convince voters of their
impartiality.
This assignment represents a scholarly attempt to evaluate the contributions of
international election observers to South African elections. On a theoretical level
it addresses the three criticisms against foreign observation. Drawing on the vast
body of international literature, the author suggests three countermeasures.
These suggestions, aimed at enhancing the contributions of international
observer consist of: 1) a greater consideration for the political context within
which an election takes place; 2) the pooling of international observer capacity
and 3) more scope to, and cooperation with, local observer groups. Each of
these measures is transferred to the South African electoral reality to establish
the extent of their application in this practical context. With regard to the first proposal the author finds that clear consideration has
been given to contextual factors in both elections. An assessment of the quality
of coordination of international observer groups also indicates that the practice of
pooling resources have been employed with success by a number of missions. In
this field the U.N. played a leading role. Cooperation between international
observers and their local counterparts is however an aspect that has been
lagging behind. The opportunity for capacity building, a significant benefit of
such cooperation, has therefore to a large extent been lost. In the light of this,
and the uncertainty of future international involvement, the author asserts that in
future South Africans will increasingly be dependent on the cultivation of
homegrown capacity. He therefore believes that initiatives such as the creation of
the SADC Electoral Forum in 1998 are commendable and should be
encouraged. / AFRIKAANSE OPSOMMING: Die fokus van internasionale verkiesingwaarneming het in die loop van die laaste
drie dekades wesenlik verskuif van die tradisionele dekolonisasie
verkiesingskonteks, na waarneming binne onafhanklike state waar die
omskakeling van outoritêre na demokratiese regeringsvorms redelik onlangs
plaasgevind het. Laasgenoemde state moes waarnemers, en die verkiesings wat
waargeneem is, met voorbehoud aanvaar. Die alternatiewe was egter beperk.
Die val van die voormalige Oosblok en die gevolglike triomf van die liberale
demokrasie, het ondemokratiese state met 'n eenvoudige keuse gelaat: hervorm
of staar isolasie in die gesig.
Pro-demokratiese groepe in voormalige outoritêre state het die nuwe klimaat van
politieke vryheid verwelkom. In die besef dat nuwe demokrasieë waarskynlik nie
oor die nodige ervaring en wedersydse vertroue binne die bevolking beskik om
verkiesings volkome te laat vlot nie, is buitelandse bystand - met inbegrip van
internasionale waarneming - deur dié groepe verwelkom. In die afgelope dekade
het die positiewe konnotasie aan internasionale verkiesingswaarneming egter in
gedrang gekom. Drie kernredes hiervoor was die skynbare gebrek aan
universele verkiesingstandaarde, swak georganiseerde waarnemer afvaardigings
en 'n algemene gebrek om hul motiewe bo verdenking te plaas.
Die sentrale oogmerk van hierdie werkstuk is die evaluasie van die bydraes
gemaak deur internasionale verkiesingswaarnemers in die twee Suid-Afrikaanse
verkiesings van 1994 en 1999. Op 'n teoretiese vlak is die drie bogenoemde
gebreke aangespreek, en na raadpleging van internasionale literatuur oor die
onderwerp is drie teenmaatreëls geidentifiseer. Hierdie aktiwiteite, gemik op
meer effektiewe internasionale betrokkenheid bestaan uit: 1) groter aandag wat
geskenk moet word aan politeke konteks; 2) die kombinering van internasionale
waarnemer vaardighede vir beter resultate, en 3) groter klem wat gelê moet word
op samewerking tussen nasionale en internasionale waarnemers. Elkeen van hierdie vereistes is oorgedra na die Suid-Afrikaanse verkiesingskonteks om vas
te stel tot watter mate dié gebruike in Suid-Afrika wortel geskied het.
Wat betref die eerste voorstel met betrekking tot konteksgebonde evaluasie, is
daar vasgestel dat dit wel deel was van internasionale waarnemer praktyk in
beide verkiesings. 'n Waardeskatting van die koordinasie van internasionale
waarnemingsgroepe dui verder daarop dat samewerking tussen
waarnemergroepe oor die algemeen bygedra het tot 'n versterking van
inisiatiewe deur internasionale waarnemers. Op hierdie gebied het die Verenigde
Nasies veral 'n sleutelrol gespeel. 'n Aspek wat egter agterweë gebly het, is die
vlak van samewerking tussen internasionale waarnemers en hul Suid-
Afrikaanse eweknieë. Hier is 'n waardevolle geleentheid verspeel om die
kapasiteit van plaaslike verkiesingswaarnemers te versterk. Dit, en die feit dat
toekomstige internasionale teenwoordigheid in die toekoms nie 'n sekerheid is
nie, sal volgens die skrywer, beteken dat Suid-Afrikaners in die toekoms
toenemend aangewese sal wees op die ontwikkeling van eie kapasiteit. In die lig
hiervan moet inisiatiewe soos SAOG se nuutgestigte Verkiesingsforum
verwelkom en aangemoedig word.
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Intégration des activités de preuve dans le processus de développement de logiciels pour les systèmes embarquésRaji, Amine 26 March 2012 (has links) (PDF)
En dépit de l'efficacité des méthodes formelles, en particulier les techniques d'analyse de modèles (model checking), à identifier les violations des exigences dans les modèles de conception, leur utilisation au sein des processus de développement industriel demeure limitée. Ceci est dû principalement à la complexité des modèles manipulés au cours de ces processus (explosion combinatoire) et à la difficulté de produire des représentations formelles afin d'exploiter les outils de vérification existants. Fort de ce constat, mes travaux de thèse contribuent au développement d'un volet méthodologique définissant les activités conduisant à l'obtention des artefacts formels. Ceux-ci sont générés directement à partir des exigences et des modèles de conception manipulés par les ingénieurs dans leurs activités de modélisation. Nos propositions s'appuient sur les travaux d'exploitation des contextes pour réduire la complexité de la vérification formelle, en particulier le langage CDL. Pour cela, nous avons proposé une extension des cas d'utilisation, afin de permettre la description des scénarios d'interaction entre le système et son environnement directement dans le corps des cas d'utilisation. Aussi, nous avons proposé un langage de spécification des exigences basé sur le langage naturel contrôlé pour la formalisation des exigences. Cette formalisation est opérée par transformations de modèle générant des propriétés CDL formalisées directement des exigences textuelles des cahiers des charges ainsi que les contextes CDL à partir des cas d'utilisations étendus. L'approche proposée a été instanciée sur un cas d'étude industriel de taille et de complexité réelles développées par notre partenaire industriel.
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Alveolar bone loss in radiographic modalities for diagnosis of periodontal disease / Periodonto ligų diagnozavimas: dantinės ataugos pokyčių analizė, taikant skirtingus rentgeninio tyrimo metodusIvanauskaitė, Deimantė 21 June 2011 (has links)
Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed. / Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti.
Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti.
Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas.
Pagal šio tyrimo... [toliau žr. visą tekstą]
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Periodonto ligų diagnozavimas: dantinės ataugos pokyčių analizė, taikant skirtingus rentgeninio tyrimo metodus / Alveolar bone loss in radiographic modalities for diagnosis of periodontal diseasesIvanauskaitė, Deimantė 21 June 2011 (has links)
Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti.
Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti.
Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas.
Pagal šio tyrimo... [toliau žr. visą tekstą] / Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed.
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INNKOMST-CTG. En vurdering av testens prediktive verdier, reliabilitet og effekt : Betydning for jordmødre i deres daglige arbeidBlix, Ellen January 2006 (has links)
No description available.
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The tool, the practice and the spatial experience. : Methods for exploring space.Emricson, Matilda January 2017 (has links)
The tool, the practice and the spatial experience. Painting to see the room Drill a small, almost invisible hole in the center of the canvas and see the room through it. Grapefruit: A Book of Instructions and Drawings by Yoko Ono I det här projektet har jag formgett och byggt en uppsättning analoga verktyg som kan användas för att utforska rum. Jag är har tittat på hur verktygen får oss att se nya kvalitéer i arkitekturen och ger oss förståelse för vår egen relation till rummet. I verktygen har jag använt ramar, speglar och rör som på olika sätt beskär, förskjuter, skapar en distans eller access i rummet . Upptäckterna delar jag sedan med mig av genom illustrationer, som hämtar inspiration både från serier och arkitektoniska representationer. Med illustrationerna vill jag skapa en diskussion och en medvetenhet om hur vi upplever rum och arkitekturen. / Painting to see the room Drill a small, almost invisible hole in the center of the canvas and see the room through it. Grapefruit: A Book of Instructions and Drawings by Yoko Ono In this project I have designed and built a set of analog tools that can be used to explore a space. I have been looking into how the objects make us see new qualities in the architecture and give us understandings about our relationship to the space. The elements I have worked with are frames, mirrors and tubes that in different ways cut, shift, create distances or access in the space. I am sharing my findings through illustrations, inspired by both comics and architecture representation. With the drawings I want to stimulate the debate and create an awareness on how we experience spaces and architecture.
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Balancing of Network Energy using Observer ApproachPatharlapati, Sai Ram Charan 02 December 2016 (has links) (PDF)
Efficient energy use is primarily for any sensor networks to function for a longer time period. There have been many efficient schemes with various progress levels proposed by many researchers. Yet, there still more improvements are needed. This thesis is an attempt to make wireless sensor networks with further efficient on energy usage in the network with respect to rate of delivery of the messages.
In sensor network architecture radio, sensing and actuators have influence over the power consumption in the entire network. While listening as well as transmitting, energy is consumed by the radio. However, if by reducing listening times or by reducing the number of messages transmitting would reduce the energy consumption. But, in real time scenario with critical information sensing network leads to information loss. To overcome this an adaptive routing technique should be considered. So, that it focuses on saving energy in a much more sophisticated way without reducing the performance of the sensing network transmitting and receiving functionalities.
This thesis tackles on parts of the energy efficiency problem in a wireless sensor network and improving delivery rate of messages. To achieve this a routing technique is proposed. In this method, switching between two routing paths are considered and the switching decision taken by the server based on messages delivered comparative previous time intervals. The goal is to get maximum network life time without degrading the number of messages at the server. In this work some conventional routing methods are considered for implementing an approach. This approach is by implementing a shortest path, Gradient based energy routing algorithm and an observer component to control switching between paths. Further, controlled switching done by observer compared to normal initial switch rule. Evaluations are done in a simulation environment and results show improvement in network lifetime in a much more balanced way.
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Individual Traits and Entrepreneurial Intentions: The Mediating Role of Entrepreneurial Self-Efficacy and Need for CognitionMiao, Chao 01 January 2015 (has links)
The field of entrepreneurship is rapidly advancing and matures as a discipline that receives substantial amount of attention. One popular area of research in the discipline of entrepreneurship is to investigate one’s intent to start a business, which is entrepreneurial intention. This is an important construct that warrants ongoing research because entrepreneurial intention is not only a great predictor of entrepreneurial behavior but also an important step in the process of becoming an entrepreneur. The present study, based on a sample of 321 subjects along with 264 observers, makes five contributions to the entrepreneurship literature. First, I examined the psychometric property of entrepreneurial take-over intention and found that it is a construct different from entrepreneurial start-up intention. Second, the results demonstrated that risk propensity and proactive personality are positive predictors of entrepreneurial start-up and take-over intentions, whereas cognitive ability is a negative predictor of entrepreneurial start-up and take-over intentions. Rebelliousness is a positive predictor of entrepreneurial take-over intention and also has an inverted U-shaped relationship with entrepreneurial take-over intention. Third, entrepreneurial self-efficacy mediates the relationship between three individual traits (i.e., emotional intelligence, risk propensity, and proactive personality) and entrepreneurial start-up and take-over intentions. Need for cognition mediates the relationship between two individual traits (i.e., cognitive ability and proactive personality) and entrepreneurial start-up intention. Fourth, 2D:4D ratio (a proxy measure for prenatal testosterone exposure level) negatively predicts risk propensity. There also exist two two-step mediations from 2D:4D ratio to both entrepreneurial start-up and take-over intentions through risk propensity and entrepreneurial self-efficacy. Fifth, the results suggest that observer ratings of individual traits only contribute modest incremental validity above and beyond self-reported ratings of them in predicting entrepreneurial start-up and take-over intentions. I discuss implications, limitations, and future directions informed by the present study.
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