Search results for "clou"
showing 10 items of 830 documents
Vendor lock-in problem in cloud storage
2015
Pilvitallennuspalvelut tuovat datan tallentamiseen ennennäkemättömiä etuja ja niiden hyödyntäminen on, sekä yksittäisillä kuluttajilla, että yrityksillä, yleistymässä. Teknologiassa on kuitenkin vielä ongelmia ilman ratkaisua. Turvallisuus-, sekä yksityisyysseikat ovat tunnetuimpia, ja niitä on tutkittu laajalti. Vähemmälle huomiolle on jäänyt, kuinka vaikeaa on palveluntarjoajan vaihtaminen. Palveluntarjoajan vaihtaminen aiheuttaa aina kustannuksia asiakkaalle. Tilannetta, jossa vaihtokustannukset ovat niin suuret, että ne estävät palveluntarjoajan vaihtamisen, kuvataan termillä "vendor lock-in" (toimittajaloukku). Tämän kandidaatintutkielman tavoitteena on kirjallisuuskatsauksen perusteel…
Financial aspects of business models : reducing costs and increasing revenues in a cloud context
2018
The emergence of cloud computing induces opportunities for software vendors and for organizations with great storage needs. Indeed, software companies have begun to adopt cloud technologies and offer their software as a service to customers instead of selling software products. As a result, their revenue models have changed, and the diversity and complexity of the resulting pricing models have created both opportunities and impediments to competition in the market. On the other hand, due to the exponentially growing volume of digital content, organizations have an increasing demand for storage and need to choose between private, public, and hybrid storage solutions. This decision requires c…
Multi-objective optimization for computation offloading in mobile-edge computing
2017
Mobile-edge cloud computing is a new cloud platform to provide pervasive and agile computation augmenting services for mobile devices (MDs) at anytime and anywhere by endowing ubiquitous radio access networks with computing capabilities. Although offloading computations to the cloud can reduce energy consumption at the MDs, it may also incur a larger execution delay. Usually the MDs have to pay cloud resource they used. In this paper, we utilize queuing theory to bring a thorough study on the energy consumption, execution delay and price cost of offloading process in a mobile-edge cloud system. Specifically, both wireless transmission and computing capabilities are explicitly and jointly co…
Adopting encryption to protect confidential data in public clouds: A review of solutions, implementation challenges and alternatives
2015
A shift towards use of public cloud services is ongoing and more and more enterprises will start to use them in the near future. As public cloud services certainly promise to deliver many benefits, this new way of delivering services also introduces new types of risks. Due to the NSA’s surveillance programs, non-US enterprises need to reassess the risks of public cloud services provided by US companies and look for available solutions to protect their confidential data transferred and stored in the cloud. Encryption is seen as a solution to help enterprises full fill the requirements related to security and privacy, but is often challenging to implement. Encryption has its own security prob…
Adversarial Attack’s Impact on Machine Learning Model in Cyber-Physical Systems
2020
Deficiency of correctly implemented and robust defence leaves Internet of Things devices vulnerable to cyber threats, such as adversarial attacks. A perpetrator can utilize adversarial examples when attacking Machine Learning models used in a cloud data platform service. Adversarial examples are malicious inputs to ML-models that provide erroneous model outputs while appearing to be unmodified. This kind of attack can fool the classifier and can prevent ML-models from generalizing well and from learning high-level representation; instead, the ML-model learns superficial dataset regularity. This study focuses on investigating, detecting, and preventing adversarial attacks towards a cloud dat…
Deju kolektīvu sistēmas Adance android lietotne
2016
“Adance” Android lietotne ir papildinājums deju kolektīvu pārvaldības un informācijas sistēmai “Adance”. Šajā darbā izstrādātais Android klients ietver sevī sistēmas tūlītējās saziņas pakalpojumu, kura izstrādes procesam līdztekus arī tika izveidota sistēmas publiskā lietojumprogrammas saskarne (API). Lietotājiem ir iespēja piekļūt savām sarunām ar citiem kolektīvu dalībniekiem, lasīt savas ziņas reāllaikā, kad tās pienāk, kā arī izveidot jaunas sarakstes, lai uzturētu kontaktu ar saviem kolektīva biedriem.
Evolution of dry season low cloud cover over the Atlantic coast of Central Africa from diurnal to interannual scale
2022
Despite its bioclimatic importance, few studies have focused on the stratiform low-level cloud cover ofthe dry season (June-September) of the Atlantic coast of Central Africa. Using in-situ data documenting theperiod 1971-2019, we show that this cloud cover is underestimated by SAFNWC satellite observations andCMIP6 models. We identify three types of days: clear, cloudy at night and totally cloudy, the latterbeing more frequent on the coast and inland, to the windward of the Cristal and Chaillu Mountains. Onan interannual scale, temperature anomalies in the South Tropical Atlantic, the equatorial Pacific and theCongo Basin, by modulating the meridional and zonal circulation cells, influence…
Quantification of Coastal New Ultra-Fine Particles Formation from In situ and Chamber Measurements during the BIOFLUX Campaign
2005
Environmental Context. Secondary processes leading to the production of ultra-fine particles by nucle- ation are still poorly understood. A fraction of new particles formed can grow into radiatively active sizes, where they can directly scatter incoming solar radiation and, if partly water soluble, contribute to the cloud condensation nuclei population. New particle formation events have been frequently observed at the Mace Head Atmospheric Research Station (western Ireland), under low tide and sunny conditions, leading to the hypothesis that new particles are formed from iodo-species emitted from macroalgae. Abstract. New particle formation processes were studied during the BIOFLUX campaig…
New particle formation inside ice clouds: In-situ observations in the tropical tropopause layer of the 2017 Asian Monsoon Anticyclone
2021
Abstract. From 27 July to 10 August 2017 the airborne StratoClim mission took place in Kathmandu, Nepal where eight mission flights were conducted with the M-55 Geophysica up to altitudes of 20 km. New Particle Formation (NPF) was identified by the abundant presence of ultrafine aerosols, with particle diameters dp smaller than 15 nm, which were in-situ detected by means of condensation nuclei counting techniques. NPF fields in clear-skies as well as in the presence of cloud ice particles (dp > 3 µm) were encountered at upper troposphere/lowermost stratosphere (UT/LS) levels and within the Asian Monsoon Anticyclone (AMA). NPF-generated ultrafine particles in elevated concentrations (Nuf)…
Collaborative Mobile Clouds: An Energy Efficient Paradigm for Content Sharing
2018
On the way toward enabling efficient content distribution, reducing energy consumption and prolonging battery life of mobile equipment, an emerging paradigm, i.e., mobile cloud, which is based on content distribution, was proposed. As a mobile platform that is oriented toward content distribution, mobile cloud is also foreseen as an energy-efficient solution for future wireless networks. The benefits of using CMC for content distribution or distributed computing from social networking perspectives have been studied earlier. In this article, we first present the concepts of CMC and then discuss the energy-efficiency benefits from the system-level point-of-view as well as open challenges in d…