1,137 research outputs found
Thermodynamic analysis of turbulent combustion in a spark ignition engine. Experimental evidence
A method independent of physical modeling assumptions is presented to analyze high speed flame photography and cylinder pressure measurements from a transparent piston spark ignition research engine. The method involves defining characteristic quantities of the phenomena of flame propagation and combustion, and estimating their values from the experimental information. Using only the pressure information, the mass fraction curves are examined. An empirical burning law is presented which simulates such curves. Statistical data for the characteristics delay and burning angles which show that cycle to cycle fractional variations are of the same order of magnitude for both angles are discussed. The enflamed and burnt mass fractions are compared as are the rates of entrainment and burning
Privacy Mining from IoT-based Smart Homes
Recently, a wide range of smart devices are deployed in a variety of
environments to improve the quality of human life. One of the important
IoT-based applications is smart homes for healthcare, especially for elders.
IoT-based smart homes enable elders' health to be properly monitored and taken
care of. However, elders' privacy might be disclosed from smart homes due to
non-fully protected network communication or other reasons. To demonstrate how
serious this issue is, we introduce in this paper a Privacy Mining Approach
(PMA) to mine privacy from smart homes by conducting a series of deductions and
analyses on sensor datasets generated by smart homes. The experimental results
demonstrate that PMA is able to deduce a global sensor topology for a smart
home and disclose elders' privacy in terms of their house layouts.Comment: This paper, which has 11 pages and 7 figures, has been accepted BWCCA
2018 on 13th August 201
SAT based Enforcement of Domotic Effects in Smart Environments
The emergence of economically viable and efficient sensor technology provided impetus to the development of smart devices (or appliances). Modern smart environments are equipped with a multitude of smart devices and sensors, aimed at delivering intelligent services to the users of smart environments. The presence of these diverse smart devices has raised a major problem of managing environments. A rising solution to the problem is the modeling of user goals and intentions, and then interacting with the environments using user defined goals. `Domotic Effects' is a user goal modeling framework, which provides Ambient Intelligence (AmI) designers and integrators with an abstract layer that enables the definition of generic goals in a smart environment, in a declarative way, which can be used to design and develop intelligent applications. The high-level nature of domotic effects also allows the residents to program their personal space as they see fit: they can define different achievement criteria for a particular generic goal, e.g., by defining a combination of devices having some particular states, by using domain-specific custom operators. This paper describes an approach for the automatic enforcement of domotic effects in case of the Boolean application domain, suitable for intelligent monitoring and control in domotic environments. Effect enforcement is the ability to determine device configurations that can achieve a set of generic goals (domotic effects). The paper also presents an architecture to implement the enforcement of Boolean domotic effects, and results obtained from carried out experiments prove the feasibility of the proposed approach and highlight the responsiveness of the implemented effect enforcement architectur
Diagnosing students' difficulties in learning mathematics
This study considers the results of a diagnostic test of student difficulty and contrasts the difference in performance between the lower attaining quartile and the higher quartile. It illustrates a difference in qualitative thinking between those who succeed and those who fail in mathematics, illustrating a theory that those who fail are performing a more difficult type of mathematics (coordinating procedures) than those who succeed (manipulating concepts). Students who have to coordinate or reverse processes in time will encounter far greater difficulty than those who can manipulate symbols in a flexible way. The consequences of such a dichotomy and implications for remediation are then considered
Data protection in elderly health care platforms
Ambient Assisted Living provides solutions to the increasing cognitive problems that affect the elderly population. To provide all features possible, Ambient Assisted Living projects require access to personal and private information of their users. Currently, the legal issues arisen in Ambient Assisted Living are a hot topic in the European Union, especially aspects regarding unsupervised data processing and cross-sharing of personal information. In this paper it is presented the iGenda project, which is a Cognitive Assistant inserted in the Ambient Assisted Living area which aims to build safe environments that adapt themselves to oneâs individual needs. However, one of the issues is the protection of the data flowing within the system and the protection of userâs fundamental rights. It is also presented the principles and legal guarantees of data protection and transmission, and legal aspects are explained, embracing appropriate solutions to technological features that may be a threat.FEDER - FederaciĂłn Española de Enfermedades Raras(TIN2015-65515-C4-1-R). COMPETE: POCI-01-0145-FEDER-007043 and FCT-Fundação para a CiĂȘncia e Tecnologia within the Project Scope UID/ CEC/00319/2013. A. Costa thanks the Fundação para a CiĂȘncia e a Tecnologia (FCT) the Post-Doc scholarship with the Ref. SFRH/BPD/102696/2014. This work is also partially supported by the MINECO/FEDER TIN2015-65515-C4-1-R
The cytotoxic and migrastatic potentials of Allium Jesdianum hydroalcoholic extract on glioblastoma multiforme cell line model
OBJECTIVE: Glioblastoma multiforme is one of the most malignant types of central nervous system tumors and temozolomide (TMZ) is currently used as a standard treatment for this type of cancer. However, resistance to temozolomide is a problem in the successful treatment. Plants and herbs are potential sources of cancer therapeutics. This study aimed at evaluating the effect of Allium Jesdianum (AJ) hydroalcoholic extract on glioblastoma multiforme cells.
MATERIALS AND METHODS: The plant material was purchased and extracted. The cell line was treated with extract for 24, 48, and 72 hr. Cell viability was assessed by trypan blue staining, MTT assay, and lactate dehydrogenase activity measurement. Tumor invasion potential was evaluated by cell migration, invasion, and adhesion tests. Real-time PCR was used to assess the changes in the expression pattern of genes involved in cancer invasion.
RESULTS: Extract treatment caused a concentration- and time-dependent decrease in cell survival. Also, a decrease in cell migration, invasion and adhesion potential and the expression of metalloproteinases 2 and 9 in cells was observed after treatment.
CONCLUSIONS: Allium Jesdianum showed promising anti-cancer activity in glioblastoma multiforme cells
EmLog:Tamper-Resistant System Logging for Constrained Devices with TEEs
Remote mobile and embedded devices are used to deliver increasingly impactful
services, such as medical rehabilitation and assistive technologies. Secure
system logging is beneficial in these scenarios to aid audit and forensic
investigations particularly if devices bring harm to end-users. Logs should be
tamper-resistant in storage, during execution, and when retrieved by a trusted
remote verifier. In recent years, Trusted Execution Environments (TEEs) have
emerged as the go-to root of trust on constrained devices for isolated
execution of sensitive applications. Existing TEE-based logging systems,
however, focus largely on protecting server-side logs and offer little
protection to constrained source devices. In this paper, we introduce EmLog --
a tamper-resistant logging system for constrained devices using the
GlobalPlatform TEE. EmLog provides protection against complex software
adversaries and offers several additional security properties over past
schemes. The system is evaluated across three log datasets using an
off-the-shelf ARM development board running an open-source,
GlobalPlatform-compliant TEE. On average, EmLog runs with low run-time memory
overhead (1MB heap and stack), 430--625 logs/second throughput, and five-times
persistent storage overhead versus unprotected logs.Comment: Accepted at the 11th IFIP International Conference on Information
Security Theory and Practice (WISTP '17
Holographic Dark Energy from a Modified GBIG Scenario
We construct a holographic dark energy model in a braneworld setup that
gravity is induced on the brane embedded in a bulk with Gauss-Bonnet curvature
term. We include possible modification of the induced gravity and its coupling
with a canonical scalar field on the brane. Through a perturbational approach
to calculate the effective gravitation constant on the brane, we examine the
outcome of this model as a candidate for holographic dark energy.Comment: 13 pages, accepted for publication in IJMP
- âŠ