Ryerson University

About: Ryerson University is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Poison control. The organization has 7671 authors who have published 20164 publications receiving 394976 citations. The organization is also known as: Ryerson Polytechnical Institute & Ryerson Institute of Technology.

Optical and acoustic properties at 1064 nm of polyvinyl chloride-plastisol for use as a tissue phantom in biomedical optoacoustics.

Abstract: A novel optoacoustic phantom made of polyvinyl chloride-plastisol (PVCP) for optoacoustic studies is described. The optical and acoustic properties of PVCP were measured. Titanium dioxide (TiO2) powder and black plastic colour (BPC) were used to introduce scattering and absorption, respectively, in the phantoms. The optical absorption coefficient (mua) at 1064 nm was determined using an optoacoustic method, while diffuse reflectance measurements were used to obtain the optical reduced scattering coefficient (mu's). These optical properties were calculated to be mua = (12.818 +/- 0.001)ABPC cm(-1) and mu's = (2.6 +/- 0.2)S(TiO2) + (1.4 +/- 0.1) cm(-1), where ABPC is the BPC per cent volume concentration, and S(TiO2) is the TiO2 volume concentration (mg mL(-1)). The speed of sound in PVCP was measured to be (1.40 +/- 0.02) x 10(3) m s(-1) using the pulse echo transmit receive method, with an acoustic attenuation of (0.56 +/- 1.01) f(1.51+/-0.06)MHz (dB cm(-1)) in the frequency range of 0.61-1.25 MHz, and a density, calculated by measuring the displacement of water, of 1.00 +/- 0.04 g cm(-3). The speed of sound and density of PVCP are similar to tissue, and together with the user-adjustable optical properties, make this material well suited for developing tissue-equivalent phantoms for biomedical optoacoustics.

Is There A Relationship Between ICT, Health, Education And Development? An Empirical Analysis of five West African Countries from 1997-2003

Abstract: For more than a decade, key international organizations such as the World Bank, International Monetary Fund, the UN and International Telecommunications Union (ITU) have argued that investment in information communication and telecommunication (ICT) infrastructure is a prerequisite for the development of poor countries. However, dissenting voices of the international development community argue that African governments should focus their attention on building schools, delivering basic health care, electricity and clean water rather than on the building of costly ICT infrastructure with their limited financial resources. In this paper, we present an analysis of the relationships among investments in ICT, Health Care and Education and the human development index on five West African nations. We use a Stepwise regression analysis to help unravel the complex relationships among these variables. Our results provide evidence that complementary investments in ICT, health and education can significantly increase development. Given that developing nations are making considerable investments in healthcare, education and ICT and that there are concerns over the type of investments they should make, our findings are a significant contribution to the literature.

A Regression Model Explaining Predisposition to Collaborate

Abstract: Using a sample of 645 nonprofit organizations in Canada, the authors construct and validate a regression model to explain predisposition to collaborate. Organizational factors such as size and type (feminist or not) were found to be related to the extent of formal collaborative activity. However, the strength of these factors as predictors of behavior was amplified or reduced by the intervening perception of the impact of environmental changes. In addition, the perception of these pressures was shown to intensify the motivation to collaborate, which in turn increases the probability of engaging in formal interorganizational activity. This study contributes to the body of knowledge about collaboration because previous research has not investigated the influence of a combination of factors on collaborative behavior.

Mobilizing knowledge: determining key elements for success and pitfalls in developing community-based tourism

Abstract: Community-based tourism (CBT) has often been cited as an alternative to mass tourism and an approach for tourism to become more sustainable. If developed well, CBT can become a poverty alleviation mechanism and a way to access improvements in quality of life, providing empowerment and greater economic benefit to individuals in local communities. Despite the plethora of literature on CBT and evaluation of models, there is little analysis of the facilitators and barriers to achieving it. Through the use of case studies in both academic and grey literature, this paper serves as an instructive review of the CBT literature to synthesize the key elements of success and the challenges.

BLA: Blockchain-Assisted Lightweight Anonymous Authentication for Distributed Vehicular Fog Services

Abstract: As modern vehicles and distributed fog services advance apace, vehicular fog services (VFSs) are being expected to span across multiple geo-distributed datacenters, which inevitably leads to cross-datacenter authentication. Traditional cross-datacenter authentication models are not suitable for the scenario of high-speed moving vehicles accessing VFS, because these models either ignored user privacy or ignored the delay requirement of driving vehicles. This paper proposes a blockchain-assisted lightweight anonymous authentication (BLA) mechanism for distributed VFS, which is provisioned to driving vehicles. BLA can achieve the following advantages: 1) realizing a flexible cross-datacenter authentication, in which a vehicle can decide whether to be reauthenticated or not when it enters a new vehicular fog datacenter; 2) achieving anonymity, and granting vehicle users the responsibility of preserving their privacy; 3) it is lightweight by achieving noninteractivity between vehicles and service managers (SMs), and eliminating the communication between SMs in the authentication process, which significantly reduces the communication delay; and 4) resisting the attack that the database governed by one center is tampered with. BLA achieves these advantages by effectively combining modern cryptographical technology and blockchain technology. These security features are demonstrated by carrying out security analysis. Meanwhile, extensive simulations are conducted to validate the efficiency and practicality of BLA.