Ograniczanie wyników
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 21

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  mobile computing
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
EN
Fog/Edge computing model allows harnessing of resources in the proximity of the Internet of Things (IoT) devices to support various types of latency-sensitive IoT applications. However, due to the mobility of users and a wide range of IoT applications with different resource requirements, it is a challenging issue to satisfy these applications' requirements. The execution of IoT applications exclusively on one fog/edge server may not be always feasible due to limited resources, while the execution of IoT applications on different servers requires further collaboration and management among servers. Moreover, considering user mobility, some modules of each IoT application may require migration to other servers for execution, leading to service interruption and extra execution costs. In this article, we propose a new weighted cost model for hierarchical fog computing environments, in terms of the response time of IoT applications and energy consumption of IoT devices, to minimize the cost of running IoT applications and potential migrations. Besides, a distributed clustering technique is proposed to enable the collaborative execution of tasks, emitted from application modules, among servers. Also, we propose an application placement technique to minimize the overall cost of executing IoT applications on multiple servers in a distributed manner. Furthermore, a distributed migration management technique is proposed for the potential migration of applications' modules to other remote servers as the users move along their path. Besides, failure recovery methods are embedded in the clustering, application placement, and migration management techniques to recover from unpredicted failures. The performance results demonstrate that our technique significantly improves its counterparts in terms of placement deployment time, average execution cost of tasks, the total number of migrations, the total number of interrupted tasks, and cumulative migration cost.
EN
Embedded platforms with GPU acceleration, designed for performing machine learning on the edge, enabled the creation of inexpensive and pervasive computer vision systems. Smartphones are nowadays widely used for profiling and tracking in marketing, based on WiFi data or beacon-based positioning systems. We present the Arahub system, which aims at integrating world of computer vision systems with smartphone tracking for delivering data useful in interactive applications, such as interactive advertisements. In this paper we present the architecture of the Arahub system and provide insight about its particular elements. Our preliminary results, obtained from real-life test environments and scenarios, show that the Arahub system is able to accurately assign smartphones to their owners, based on visual and WiFi/Bluetooth positioning data. We show the commercial value of such system and its potential applications.
3
EN
New kinds of data collection like GPS-tracking, wearable sensors and mobile apps impose both technical and privacy challanges for medical research. In the MOPS study (''Machbarkeitsstudie für Ortsbezogene Parameter und Sensordaten'' - feasibility study for geocoded parameters and sensor data) we provide participants with a newly developed app and sensors for various physical and environmental parameters. We want to explore the feasibility of the recently established Medical Research Platform of the Medical Faculty of the University of Leipzig and similar platforms for this kind of data collection and processing.
4
Content available remote Generating human mobility route based on generative adversarial network
EN
Recently, many researches on human mobility are aiming to suggest the personal customized solution in the diverse field, usually by academia and industry. Combined with deep learning methods, the mobility data can predict and generate routes of objects from the given past trends. In this work, the Generative Adversarial Network (GAN) model is introduced for creating individual mobility routes based on sets of accumulated personal mobility data. The mobility data had been collected by use of geopositioning system and personal mobile devices. GAN has Discriminator and Generator which are composed of neural networks, and can extract and train geopositionig information. A sequence of longitude and latitude can be geographically mapped and such images can be handled by GAN. The GAN based model successfully handled individual mobility routes in this way. Consequently, our model can generate and suggest unexplored routes from the existing sets of personal geolocation data.
EN
The government of Saudi Arabia has adopted M-Government for the effective delivery of services. One advantage that it offers is unique opportunities for real-time and personalized access to government information and services. However, a low adoption rate of m-Government services by citizens is a common problem in Arab countries, including Saudi Arabia, despite the best efforts of the Saudi government. Therefore, this paper explores the determinants of citizens' intention to adopt and use m-Government services, in order to increase the adoption rate. This study was based on the Mobile Government Adoption and Utilization Model (MGAUM) that was developed for the purpose. Data was collected, and the final sample consisted of 1,286 valid responses. The descriptive analysis presented in this paper indicates that all the proposed factors in our MGAUM model were statistically significant in influencing citizens' intention to adopt and use m-Government services.
EN
The variety of hardware devices and the diversity of their users imposes new requirements and expectations on designers and developers of mobile applications (apps). While the Internet has enabled new forms of communication platform, online stores provide the ability to review apps. These informal online app reviews have become a viral form of electronic word-of-mouth (eWOM), covering a plethora of issues. In our study, we set ourselves the goal of investigating whether online reviews reveal usability and user experience (UUX) issues, being important quality-in-use characteristics. To address this problem, we used sentiment analysis techniques, with the aim of extracting relevant keywords from eWOM WhatsApp data. Based on the extracted keywords, we next identified the original users' reviews, and individually assigned each attribute and dimension to them. Eventually, the reported issues were thematically synthesized into 7 attributes and 8 dimensions. If one asks whether online reviews reveal genuine UUX issues, in this case, the answer is definitely affirmative.
EN
Many governments worldwide are taking advantage of the latest developments in mobile technology to take the digital delivery of government information and services (e-government) to their citizens a stage further. Accessing government information and services via a mobile device is known as m-government, a system designed to serve citizens, companies and government agencies alike. M-government also has unique advantages over e-government, not least enabling users to access government services at any time and from any location. This paper presents a pilot study of the MGAUM model that was developed to analyze factors influencing the adoption rate of m-government services in Saudi Arabia. With the aim of validating a survey instrument with which to conduct the main study in Saudi Arabia, a pilot survey instrument was developed and modified by using previous instruments from research into both e-government and m-government. This pilot questionnaire was distributed to 71 Saudi citizens in the UK, and the final sample was 58 valid responses. The results of this pilot study reveal that all items in the survey instrument were reliable and valid within the range of acceptable academic research and suitable for use in the main study. The results of this pilot study were analyzed using SPSS.
EN
There has been research regarding relationship between human personalities and visiting places using Big Five Factor (BFF). However, other factors such as Social media usage, Hobby, Gender, Age, and Religion and so on are regarded as also major factors which effects the choice of visiting place of a person. Using questionnaire designed by authors, these factors as well as BFF were prepared for this research. The visiting places were collected by a smartphone app called SWARM and classified in 10 categories. In sum, personal data of 34 participants had been collected for several months. To figure out the relationship between these factors and visiting places, random forest technique of ensemble method was used.
EN
Mobile Computing and Mobile Cloud Computing are the areas where intensive research is observed. The “mobility” landscape (devices, technologies, apps, etc.) evolves so fast that definitions and taxonomies do not catch up with so dynamic changes and there is still an ambiguity in definitions and common understanding of basic ideas and models. This research focuses on Mobile Cloud understood as parallel and distributed system consisting of a collection of interconnected (and virtualized) mobile devices dynamically provisioned and presented as one unified computing resource. This paper focuses on the mobile green computing cloud applied for parallel and distributed computations and consisting of outdated, abandoned or no longer needed smartphones being able to set up a powerful computing cluster. Besides showing the general idea and background, an actual computing cluster is constructed and its scalability and efficiency is checked versus the results obtained from the virtualized set of smartphones. All the experiments are performed using a dedicated software framework constructed in order to leverage the nolonger-needed smartphones, creating a computing cloud.
EN
This paper presents an application of built-in sensors of a mobile device – a more robust version of authors’ own motion type detection method introduced in previous work. Use of accelerometer and magnetometer for recording acceleration in the World’s coordinate system is explained. The original results and identification criteria are briefly described. New tests and their results are presented. An improved version of the motion type identification method is introduced.
PL
Artykuł przedstawia zastosowanie sensorów urządzeń mobilnych – bardziej rozbudowaną wersję autorskiej metody identyfikacji rodzaju ruchu. Metoda ta została zaproponowana we wcześniejszej pracy. Krótko omówione zostało zastosowanie akcelerometru i magnetometru do pomiaru przyspieszenia we współrzędnych świata. Przedstawiono wyniki wstępnych pomiarów razem z oryginalnymi kryteriami rozpoznawania ruchu. Opisano nowe przeprowadzone eksperymenty i ich wyniki. Zaproponowano ulepszoną wersję metody rozpoznawania rodzaju ruchu.
11
Content available remote Parallel Code Generation for Mobile Devices
EN
Mobile computing is driven by pursuit of ever increasing performance. Multicore processing is recognized as a key component for continued performance improvements. This paper presents the Iteration Space Slicing (ISS) framework aimed at automatic parallelization of code for Mobile Internet Devices (MID). ISS algorithms permit us to extract coarse-grained parallelism available in arbitrarily nested parameterized loops. The loops are parallelized and transformed to multi-threaded application for the Android OS. Experimental results are carried out by means of the benchmark suites (UTDSP and NPB) using the ARM dual core processor. The related parallelization techniques are discussed, in particular for embedded systems. The future work is outlined.
PL
Przetwarzanie obliczeń za pomocą urządzeń mobilnych wiąże się z rosnącym zapotrzebowaniem na moc ich procesorów. Artykuł przedstawia zastosowanie narzędzia ISS (podziału przestrzeni iteracji pętli programowych) do wyznaczenia równoległego kodu dedykowanego dla urządzeń mobilnych (MID). Algorytmy pozwalają na wyznaczenie równoległości gruboziarnistej dla dowolnie zagnieżdżonych pętli i wygenerowanie wielowątkowego kodu dla systemu Android. Wyniki eksperymentalna dla zestawów pętli testowych NAS i UTDSP przeprowadzono wykorzystując dwurdzeniowy procesor ARM. Prace pokrewne i przyszłe zadania przedstawiono na końcu artykułu.
12
Content available remote Automatic Extraction of Parallelism for Mobile Devices
EN
This paper presents the Iteration Space Slicing (ISS) framework aimed at automatic parallelization of code for Mobile Internet Devices (MID). ISS algorithms permit us to extract coarse-grained parallelism available in arbitrarily nested parameterized loops. The loops are parallelized and transformed to multi-threaded application for the Android OS. Experimental results are carried out by means of the benchmark suites (UTDSP and NPB) using an ARM quad core processor. Performance benefits and power consumption are studied. Related and future work are discussed.
XX
Artykuł przedstawia ekstrakcję niezależnych fragmentów kodu dla urządzeń przenośnych. Narzędzie pozwala na zrównoleglenie gruboziarniste dowolnie zagnieżdżonych pe˛ tli programowych z parametrami do kodu wielowątkowego dla systemu Android. Eksperymenty przeprowadzono na zestawach pętli testowych (UTDSP i NPB) za pomocą czterordzeniowego procesora ARM. Przedstawiono analizę wydajności i poboru mocy oraz pokrewne rozwiązania.
13
Content available An Android Security Policy Enforcement Tool
EN
The Android operating system (OS) has become the dominant smart phone OS in recent years due to its accessibility, usability and its open-source philosophy. Consequently, this has also made it a popular target for attackers who aim to install malware on Android devices and take advantage of Android’s coarsegrained, non-revoking permission system. This project designs, implements and evaluates a security tool named COMBdroid, which addresses these security concerns in Android by enforcing fine-grained, user-defined policies. COMBdroid modifies an application before installation, allowing it to override points of security vulnerabilities at run-time. As a proof of concept we have implemented three policies in COMBdroid. This paper documents the development process of COMBdroid, deriving design decisions from the literature review, detailing the design and implementation, and proving the program’s effectiveness through evaluation.
PL
W niniejszym artykule dokonano porównania wydajności podstawowych metod całkowania zaimplementowanych w środowisku App Inventor oraz Java dla platformy Android. Wybrane metody (prostokątów, trapezów i Simpsona) zastosowano dla funkcji liniowej, sześciennej oraz sinusoidy. Rezultaty eksperymentu wykazały, że działanie algorytmów zaimplementowanych w App Inventor jest wielokrotnie wolniejsze niż w Java dla Android, co znacząco ogranicza przydatność środowiska App Inventor do tworzenia aplikacji realizujących obliczenia matematyczne.
EN
This paper presents comparison of efficiency of basic integration methods implemented in App Inventor and Java for Android environment. Chosen methods (rectangle, trapezoidal and Simpson’s rules) were applied for linear, cubic and sine functions. Conducted experiment revealed that applications developed in App Inventor were significantly slower than in case of Java, which makes App Inventor unsuitable for applications involving intensive calculations.
EN
Mobile devices have become an integral part of our life and provide dozens of useful services to their users. However, usability of mobile devices is hindered by battery lifetime. Energy conservation can extend battery lifetime, however, any energy management policy requires accurate prediction of energy consumption, which is impossible without reliable energy measurement and estimation methods and tools. We present an analysis of the energy measurement methodologies and describe the implementations of the internal (profiling) software (proprietary, custom) and external software-based (Java API, Sensor API, GSM AT) energy measurement methodologies. The methods are applied to measure energy consumption on a variety of mobile devices (laptop PC, PDA, smart phone). A case study of measuring energy consumption on a mobile computer using 3DMark06 benchmarking software is presented.
EN
An aggregate signature scheme allows a public algorithm to aggregate n signatures on n distinct messages from n signers into a single signature. By validating the single resulting signature, one can be convinced that the messages have been endorsed by all the signers. Certificateless aggregate signatures allow the signers to authenticate messages without suffering from the complex certificate management in the traditional public key cryptography or the key escrow problem in identity-based cryptography. In this paper, we present a new efficient certificateless aggregate signature scheme. Compared with up-to-date certificateless aggregate signatures, our scheme is equipped with a number of attracting features: (1) it is shown to be secure under the standard computational Diffie-Hellman assumption in the random oracle model; (2) the security is proven in the strongest security model so far; (3) the signers do not need to be synchronized; and (4) its performance is comparable to the most efficient up-to-date schemes. These features are desirable in a mobile networking and computing environment where the storage/ computation capacity of the end devices are limited, and due to the wireless connection and distributed feature, the computing devices are easy to be attacked and hard to be synchronized.
17
Content available remote A multi-facet approach to dynamic agent systems
EN
We are concerned with the problem of defining a complex, hybrid, agent based discrete system in a modular way. The modularity results from looking at the system from a numbci of different perspectives, each dealing with a specific aspect of the system. As a solution a synchronisation operator is proposed which glues agent aware systems on shared agents and transitions. The construction turns out to be a categorical product. We also show that a logic to talk about the temporal and the structural properties of the product can be obtained by gluing suitable logical frameworks from the components.
PL
W pracy rozważa się problem modularnego definiowania złożonych, hybrydowych, dyskretnych systemów agentowych. Modularność wynika z patrzenia na system z różnych perspektyw, z których każda opisuje pewne specyficzne jego aspekty. Zdefiniowano operator, który synchronizuje systemy agentoiuo zorientowane w oparciu o wspólnych agentów oraz tranzycje. Konstrukcja operatora synchonizującego okazuje się być produktem w odpowiedniej kategorii. Pokazano także, że logikę opisu temporalnych i strukturalnych własności systemu agentowego, będącego produktem perspektyw, można otrzymać przez odpowiednie złożenie systemów logicznych dla perspektyw.
18
Content available MUMMY - mobile knowledge management
EN
The project MUMMY funded by the European Commission develops means to improve the efficiency of mobile business processes through mobile, personalized knowledge management. MUMMY approaches the challenges of modern mobile work processes. To do so, it takes advantages of latest achievements in mobile connectivity and its capabilities (like "always on-line" high bandwidth personalization ubiquity), latest hardware options like camera-equipped hand- held devices, and uses multimedia, hypermedia, and semantic web technologies. Technical development and appliance of the results are intensively consulted and integrated with business processes of several commercial organizations that are members of the MUMMY consortium. In this paper the achievements of MUMMY are introduced and individual components are briefly described.
EN
In the paper an evaluation and optimisation framework for medical data access systems user interface is presented. User interface design seems to be of crucial importance for clinical data access applications acceptance, in particular for the applications running on handheld computers where the interface tools are significantly limited. The ease of program use depends strongly on the correct user interface design and on the algorithms which try to predict the user decisions and interactions made in the process of data access or modification. If the program is able to correctly predict the user actions and fetch him reasonable defaults then the number of interface actions which the user must do is significantly reduced. The method presented here focuses on typical functions available in clinical mobile data access systems: medication prescriptions and diagnostic and laboratory tests orders. The user interaction with an application is considered as the sequence of decisions. Using the records stored in the hospital database, the algorithm finds the most probable decisions at the subsequent stages of the interaction and uses it as defaults presented to the user. In this way instead of entering the data from the keyboard the user can much faster select it from the list.
EN
In the paper the concept, main design problems, applied solutions and some implementation details of a hospital information system based on handheld computers are presented. Increasing power and low prices of handheld computers make it very convenient tool for mobile information systems in medicine and health care. Permanent availability of patients data to nursing personnel and physicians at the patient’s bed make medical decision making easier, more accurate, reduces the risk of mistakes, eliminates unnecessary paper works and provides more up-to-date information. The purpose of the system being described here is to utilize all these advantages of mobile computing at the relatively low costs of hardware and software.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.