Type

Database

Creator

Date

Thumbnail

Search results

81,703 records were found.

Graphene, two dimensional sheet of carbon atoms has recently gained attention as some of its properties are very useful for electronics, optoelectronics and photovoltaic applications. Its high mobility makes it useful in radio-frequency applications and its transparency makes it useful as transparent electrodes in photovoltaics. It is known that chemical vapor deposition (CVD) is one of the techniques that can be used to synthesize graphene. A lot of work has been done on selecting appropriate substrates and hydrocarbon sources. Nickel, having a high solubility at high temperatures has been in focus lately. Ethylene which has a lower breaking point compared to other hydrocarbons has a good efficiency in the synthesis of graphene. Complexity associated with graphene synthesis and transfers onto transparent substrates constitute the majo...
How do children learn about possibility? About what is physically impossible versus what is merely improbable or unexpected and could occur under the right imagined circumstances? Recent developmental research shows younger children to frequently be more skeptical than older children about unusual events. I provide evidence that parents' explanations are an even larger predictor of the variation found in children's possibility thinking than children's age. Building on a prior study, the current study found variations in the frequencies of 62 parents' speculative, skeptical and requesting explanations during a picture book discussion with their 5-to-8-year-old child. These differences in parental talk were related to parent's artistic, scientific and other vocations. Importantly, differences in parental explanations predicted children's...
Nano-sized magnetic particles represent considerable interests in modern science because their properties are advantageous to applications such as data storage and medical science. In particular, superparamagnetism is a magnetic property which is found in nano-sized (approximately less than 20 nm) ferromagnetic or ferrimagnetic particles. Studies have shown that superparamagnetic material shows ferromagnetic magnetization only with an external magnetic field; without an external magnetic field, it loses magnetic properties even at ambient temperature overcoming its intrinsic anisotropy energy. From a magnetic memory standpoint, as bit size decreases, superparamagnetism is a major obstacle to thermal stability due to this volatility, resulting in a loss of information. If it is possible to modulate the superparamagnetic properti...
Factor mixture modeling is an increasingly popular method used in applied research settings that combines latent class models and common factor models. The method is often used to detect the presence of heterogeneous populations (i.e., latent classes) that differ on one or more population parameters of a factor model in a sample that lacks a priori information regarding population membership. Researchers have faced many challenges when using the factor mixture modeling method. The present study employs a Monte Carlo approach to compare the performance of factor mixture modeling with three other tenable methods: Q-Factor Analysis, Marcoulides and Drezner Model, and McDonald Eigen Analysis, in detecting latent classes in a sample. Data were simulated by manipulating six design factors: sample size, number of classes, mi...
Increased activity at ports is an indication of economic development and growth; however, it also puts public health, regional air quality and global climate at risk because the exhaust from the marine diesel engines is not subjected to the stringent regulations as on-road engines. This dissertation characterizes the effectiveness of strategies and technologies to mitigate criteria pollutants and the long-lived greenhouse gas, carbon dioxide (CO2) from marine diesel engines. The dissertation also provides insight into the current state-of-art of gaseous and particulate matter portable emission measurement system (PEMS). Results from a project show how to determine the measurement allowance for PEMS in order to provide accurate measurements for the development of emission inventories and subsequently, air pollution mitigating regulation...
Next generation 4G LTE-Enhanced wireless cellular networks are designed to provide broadband high speed transport services to mobile users. Due to the scarcity of spectral resources that can be employed, it is essential for the networks to engage in multi-dimensional adaptations in the dynamic assignment of wireless access resources. The robustness of wireless cellular networks is also of importance, since failures or degradations of network elements inevitably lead to major network service disruptions. Thus, efficient failover mechanisms are required to handle this scenario. This dissertation introduces efficient adaptive scheduling algorithms for multicast and unicast downlink transmission operations in cellular wireless networks. Under multicast operations, the newly developed adaptive power scheduling algorithms enable base statio...
With the continuous scaling of CMOS technology, two opposite trends can be observed. First trend is exponential improvement of the digital logic and second trend is linear degradation of the analog and RF components. Traditional methodology for designing analog and RF focuses on optimizing the performance of individual blocks such as analog-to-digital converters, frequency synthesizers, etc. Unfortunately, such traditional approach is limited by the unforgiving power-consumption-performance tradeoffs encountered in the design of each circuit block. As a result, high power consumption of RF and analog has become a major bottleneck for implementation of new communication algorithms. Alternatively, one can "assist" the underperforming RF and analog blocks using cross-domain (RF-analog-digital) techniques. Such cross-domain approach le...
Fables of attention are didactic stories about the consequences of how we attend to the world. They act on our sensoria; they teach us how to pay attention. In this dissertation, which is located in the field of Science and Technology Studies (STS), I use the genre of the fable to explore the relationship between attention and storytelling across different ecologies of practice. Specifically, I focus on wonder as a mode of attention in feminist theory and scientific practice. As I read and write fables of attention, wonder does not stay still; it transforms and accrues different meanings as the chapters unfold.Chapter 1 looks at wonder as epistemological dilation in the scientific articles of American ichthyologist E.W. Gudger (1866-1965), showing how it shaped his scientific objects and guided his passionate empiricism. Chapter 2 ...
Microbial populations observed in the microbiome of Acrobeloides maximus consistently comprised a set of different microorganisms compared to the microbiome of Caenorhabditis elegans or the metagenome of the soil sample to which nematodes were exposed. Using 16S rRNA gene amplification, the bacterial genera Ochrobactrum, Pedobacter, and Chitinophaga were identified at significant levels within the A. maximus communities only and were found to be consistently present during each of the three sampling periods over six months. We were able to isolate and grow colonies of Ochrobactrum and Pedobacter from the microbiome of the nematode on Lysogeny Broth-Miller (LB) and Yeast Extract (YE) agar plates. We wer...
Want to know more?If you want to know more about this cutting edge product, or schedule a demonstration on your own organisation, please feel free to contact us or read the available documentation at http://www.keep.pt/produtos/retrievo/?lang=en