Miracle-dz/UniFAR-FTUs huggingface dataset:
The World of Carbon Nanotubes: An Overview of CVD Growth Methodologies

Carbon nanotubes are a new form of completely artificial crystalline carbon, which have never been found as a natural form. These fascinating hollow cylinders can be considered as prototypes of one-dimensional quantum wires, exhibit peculiar chemical- physical properties very different from those of other C-based nanostructures, and are envisaged to have potential in a wide range of applications. This review examines some of the most interesting CVD methodologies employed for the synthesis of carbon nanotubes. The results obtained from different methodologies demonstrate that carbon nanotubes can be grown by CVD under a wide range of experimental conditions, permitting flexible, tunable synthesis. Overall, in the last few years, CVD approaches have emerged as the most promising among those proposed for synthesizing carbon nanotubes.
Persuasive design of a mobile energy conservation game with direct feedback and social cues

Pervasive gaming has the potential of transforming the home into a persuasive environment in which the user can learn about appliances and their electricity consumption. Power Explorer is a mobile game with a special sensing approach that provides real-time electricity measurements and feedback when the user switches on and off devices in the home. The game was developed based on persuasive principles to provide an engaging means to learn about energy with positive and negative feedback and social feedback from peers on real energy actions in the home. We present the design and rationale of this game and discuss how pervasive games can be viewed from a persuasive and learning point of view.
Biometric Methods for Secure Communications in Body Sensor Networks: Resource-Efficient Key Management and Signal-Level Data Scrambling

As electronic communications become more prevalent, mobile and universal, the threats of data compromises also accordingly loom larger. In the context of a body sensor network (BSN), which permits pervasive monitoring of potentially sensitive medical data, security and privacy concerns are particularly important. It is a challenge to implement traditional security infrastructures in these types of lightweight networks since they are by design limited in both computational and communication resources. A key enabling technology for secure communications in BSN's has emerged to be biometrics. In this work, we present two complementary approaches which exploit physiological signals to address security issues: (1) a resource-efficient key management system for generating and distributing cryptographic keys to constituent sensors in a BSN; (2) a novel data scrambling method, based on interpolation and random sampling, that is envisioned as a potential alternative to conventional symmetric encryption algorithms for certain types of data. The former targets the resource constraints in BSN's, while the latter addresses the fuzzy variability of biometric signals, which has largely precluded the direct application of conventional encryption. Using electrocardiogram (ECG) signals as biometrics, the resulting computer simulations demonstrate the feasibility and efficacy of these methods for delivering secure communications in BSN's.
A Conjecture of Chinese Monetary Policy Rule: Evidence from Survey Data, Markov Regime Switching, and Drifting Coefficients

This paper studies a modified Chinese Taylori¯s rule with money supply growth rate as the intermediate target. We develop survey data to measure the expected inflation and use the real marginal cost as a proxy for the output gap. The Markov regime switching model, the TVP model and the split sample OLS estimation are employed to estimate the changing coefficients of the monetary reaction function. We find that there were two structural changes in the Chinese monetary policy rule, which take the form of discrete jumps rather than continuous adjustments. Besides, the Chinese central bank is not purely forward-looking as most literature assumed.
3D Micro‐Extrusion of Graphene‐based Active Electrodes: Towards High‐Rate AC Line Filtering Performance Electrochemical Capacitors

A facile one‐step printing process by 3D micro‐extrusion affording binder‐free thermally reduced graphene oxide (TRGO) based electrochemical capacitors (ECs) that display high‐rate performance is presented. Key intermediates are binder‐free TRGO dispersion printing inks with concentrations up to 15 g L−1. This versatile printing technique enables easy fabrication of EC electrodes, useful in both aqueous and non‐aqueous electrolyte systems. The as‐prepared TRGO material with high specific surface area (SSA) of 593 m2 g−1 and good electrical conductivity of ≈16 S cm−1 exhibits impressive charge storage performances. At 100 and 120 Hz, ECs fabricated with TRGO show time constants of 2.5 ms and 2.3 ms respectively. Very high capacitance values are derived at both frequencies ranging from 3.55 mF cm−2 to 1.76 mF cm−2. Additionally, these TRGO electrodes can be charged and discharged at very high voltage scan rates up to 15 V s−1 yielding 4 F cm−3 with 50% capacitance retention. Electrochemical performance of TRGO electrodes in electrolyte containing tetraethyl ammonium tetrafluoroborate and acetonitrile (TEABF4‐ACN) yields high energy density of 4.43 mWh cm−3 and power density up to 42.74 kW cm−3, which is very promising for AC line filtering application and could potentially substitute state of the art electrolytic capacitor technology.
Streamer discharge reduces pollen-induced inflammatory responses and injury in human airway epithelial cells

Although epidemiological studies have demonstrated that cedar pollen influences respiratory health, effective method for inactivating cedar pollen has not been established. Streamer discharge is a type of plasma discharge in which high-speed electrons collide with oxygen and nitrogen molecules. It reportedly has the ability to eliminate bacteria, mould, chemical substances and allergens. The present study investigated the influence of pollen on BEAS-2B cell line, derived from human airway epithelial cells, as well as the efficiency of streamer discharge on pollen-induced health effects. Airway epithelial cells were exposed to non-treated pollen and streamer-discharged pollen at doses of 100 and 1000 μg/mL for 6 or 24 h. Non-treated pollen at a dose of 1000 μg/mL significantly decreased cell viability and induced both mRNA and protein expression of interleukin-6, whereas streamer-discharged pollen showed the attenuated changes as compared with non-treated pollen. Further, scanning electron micrographs showed that streamer discharge caused the fine structural changes of pollen. These results provide the first experimental evidence that pollen at a high dose affects cell viability and inflammatory responses, and streamer discharge technology attenuates their influences by decomposing pollen.
Leg extensor power and functional performance in very old men and women.

1. Residents of a chronic care hospital (13 men of mean age 88.5 +/- 6 SD years and 13 women of mean age 86.5 +/- 6 SD years) who had multiple pathologies were assessed for leg extensor capability in several ways. 2. A custom-built rig was used to assess leg extensor power, that is, maximal power output over less than 1 s in a single extension of one leg. Performance measures were obtained by timing chair rises (from a standard chair 0.43 m high), stair climbing (four risers, total height 0.635 m) and a walk (6.1 m). For each measurement the best of several trials were recorded as definitive. 3. Leg extensor power was significantly correlated with all performance measures, but the performance measures were not related to each other except for chair rising and walking speed. 4. Women had significantly less extensor power than men, but their power explained more of the variance in performance, e.g. power accounted for 86% of the variance in walking speed. 5. There was no relation within the group between age and any of the variables measured. 6. Measurement of leg extensor power in frail elderly people may prove useful in focusing effective rehabilitation programmes.
The B-ternary logic and its applications to the detection of hazards in combinational switching circuits

Both the steady states and some transient states of switching circuits can be described by B-ternary logic in which the truth values 0, 1 and 1/2 are used respectively to represent false, true and uncertainty. This paper showed the methods of detecting and identifying various kinds of static hazards contained in combinational switching circuits by means of the canonical forms of the B-ternary logic functions realized by the circuits. Particularly, a method was derived which could algebraically detect all logic hazards contained in the circuits. It was also pointed out that there were some dynamic hazards which were detectable by B-ternary logic.
Experimental Analysis of Lag Sources in Pinned Photodiodes

A measurement method is reported to distinguish the different mechanisms that lead to image lag in image sensors based on pinned photodiodes (PPDs). This new method can differentiate between the lag caused by a potential barrier or pocket and gate traps independently of charge spill-back. This is in contrast to usual lag characterization techniques, which only provide a quantitative measurement of the photocharge amount that is not transferred to the sense node in the frame of interest. The method reveals itself as useful to optimize pixels for high-speed and low-noise sensors based on PPDs.
Electrochemical Characterization of Low Temperature Thermal Aging Embrittlement of Stainless Steel 304L Weld

Thermal aging embrittlement of type 304L stainless steel weld is investigated on the basis of changes in microstructure, microhardness and electrochemical behavior after aging up to 20,000 h at 335, 365 and 400 °C. Spinodal decomposition and G-phase precipitation in the ferrite was observed after thermal aging. Aging led to increase in the hardness of ferrite phase while there was no change in the hardness of austenite. The changes in electrochemical behavior due to aging were studied using double loop electrochemical potentiokinetic reactivation (DL-EPR) test. Aging led to increase in the DL-EPR value which is attributed to Cr depletion in the ferrite phase.
Reinforcing effects of graphene oxide on portland cement paste

In this experimental study, the reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is discovered that the introduction of 0.03% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength of the cement composite by more than 40% due to the reduction of the pore structure of the cement paste. Moreover, the inclusion of the GO sheets enhances the degree of hydration of the cement paste. However, the workability of the GO-cement composite becomes somewhat reduced. The overall results indicate that GO could be a promising nanofillers for reinforcing the engineering properties of portland cement paste.
Conserved Pro-Glu (PE) and Pro-Pro-Glu (PPE) Protein Domains Target LipY Lipases of Pathogenic Mycobacteria to the Cell Surface via the ESX-5 Pathway*

The type VII secretion system ESX-5 is a major pathway for export of PE and PPE proteins in pathogenic mycobacteria. These mycobacteria-specific protein families are characterized by conserved N-terminal domains of 100 and 180 amino acids, which contain the proline-glutamic acid (PE) and proline-proline-glutamic acid (PPE) motifs after which they are named. Here we investigated secretion of the triacylglycerol lipase LipY, which in fast-growing mycobacteria contains a signal sequence, but in slow-growing species appears to have replaced the signal peptide with a PE or PPE domain. Selected LipY homologues were expressed in wild-type Mycobacterium marinum and its corresponding ESX-5 mutant, and localization of the proteins was investigated by immunoblotting and electron microscopy. Our study shows that Mycobacterium tuberculosis PE-LipY (LipYtub) and M. marinum PPE-LipY (LipYmar) are both secreted to the bacterial surface in an ESX-5-dependent fashion. After transport, the PE/PPE domains are removed by proteolytic cleavage. In contrast, Mycobacterium gilvum LipY, which has a signal sequence, is not transported to the cell surface. Furthermore, we show that LipYtub and LipYmar require their respective PE and PPE domains for ESX-5-dependent secretion. The role of the PE domain in ESX-5 secretion was confirmed in a whole cell lipase assay, in which wild-type bacteria expressing full-length LipYtub, but not LipYtub lacking its PE domain, were shown to hydrolyze extracellular lipids. In conclusion, both PE and PPE domains contain a signal required for secretion of LipY by the ESX-5 system, and these domains are proteolytically removed upon translocation.
Reduction of Search Space to Annotate Monolingual Corpora

Monolingual corpora which are aligned with similar text segments (paragraphs, sentences, etc.) are used to build and test a wide range of natural language processing applications. The drawback wanting to use them is the lack of publicly available annotated corpora which obligates people to make one themselves. The annotation process is a time consuming and costly task. This paper describes a new corpus-based measure to significantly reduce the search space for a faster and easier manual annotation process for monolingual corpora. This measure can be used in making alignments on different types of text segments. The performance of this measure is evaluated on a manually annotated paragraph corpus, whose alignments are freely available, with promising results.
Optimality principles in variable stiffness control: The VSA hammer

The control of a robot's mechanical impedance is attracting increasing attention of the robotics community. Recent research in Robotics has recognized the importance of Variable Stiffness Actuators (VSA) in safety and performance of robots. An important step in using VSA for safety has been to understand the optimality principles that regulate the synchronized variation of stiffness and velocity when moving in the shortest time while limiting possible impact forces (the safe brachistochrone problem). In this paper, we follow a similar program of understanding the use of VSA in performance enhancement, looking at very dynamic tasks where impacts are maximized. To this purpose we address a new optimization problem that consists in choosing the inputs for maximizing the velocity of a link at a given final position, such as, e.g., for maximizing the effect of a hammer impact. We first study the problem with fixed stiffness, and show that, under realistic modeling assumptions, there does exist an optimal linear spring for the given inertia and motor. We then study optimal control of VSA and show that varying the spring stiffness during the execution of the hammering task improves the final performance substantially. The optimal control law is obtained analytically, thus providing insight in the optimality principles underpinning general VSA control. Finally, we show the practicality of our theoretical results with experimental tests.
Development of a Spherical Air Bearing Positioning System

In line with the general trend of the automation, spherical motion systems are increasingly required in applications such as robot joints, manipulators, orientation control systems, and angular alignment systems. In this paper, a spherical air bearing positioning system (SABS) aiming at providing highly precise rotational motions in two degrees of freedom is designed. The SABS mainly consists of direct-drive voice coil actuators and pneumatic bearing. This paper presents the mechanical structure and control system of the SABS. The model of the SABS is identified based on adaptive control concepts. To eliminate the measurement noise, a noise filter is designed on the basis of the model. Then, an observer-based PID controller is designed and implemented on a dSPACE development card. The experiment results show that the designed controller can achieve higher precision and better tracking performance of about ten times compared to that from a traditional PID controller.
An Orthogonal Experimental Analysis of WEDM-HS of Al2O3 Particle-Reinforced Aluminum Alloy 6061 with 10-Vol% Al2O3

In wire electro-discharge machining with an extremely high travelling speed of wire electrode (WEDM-HS), the emulsion is used as working liquid. Because there exists a functional electrolyte, the EDM spark can operate under a relatively large spark gap size condition, and this would facilitate the removal of machined debris. An investigation has been made into the machining feasibility when WEDM-HS has been employed to process Al2O3 particle reinforced aluminum alloy 6061 with 10-vol% Al2O3 (10ALO). And the material removal rate (MRR) has been examined in this study. Since there are many factors that can influence the MRR in the WEDM-HS process, in order to determine which is the most important factor and to optimize the machining parameters, the relative importance of the various machining parameters on material removal rate was established by utilizing an orthogonal experimental analysis. The results of the analysis suggest that to achieve a high MRR for particulate reinforced aluminum 6061 with 10-vol% Al2O3, the duty cycle is the most influential factor among current, pulse duration and duty cycle. And the impact of the different factors follows the sequence of duty cycle > current > pulse duration.
Embedded module for image processing

This thesis presents a complete hardware and software design of an embedded computer vision module based on a low-end FPGA platform capable of real-time mobile robot navigation. The core of the presented work is a method for a real-time image feature extraction and matching, which is completely implemented in the FPGA fabric. The method implements all stages required for visual-based teach-and-repeat mobile robot navigation, i.e. detection of salient points in the image, description of their surroundings, establishing their correspondence with a known map and calculation of the robot’s steering commands. Moreover three years of experience and continuous research in the fields of FPGA prototyping, computer vision and mobile robotics resulted in a generalization of complete methodology and framework for acceleration of computer vision applications on the FPGA platform which is also presented in the thesis. The proposed embedded module performance is evaluated in the end of this thesis and compared to the other embedded solutions used in the field of the mobile robotics.
Ageing of Foamed Polyurethane

This report from the Norwegian Building Research Institute on tests which spanned up to ten years shows how the heat insulation properties of foamed polyurethane decline with age (increase in the λ-value). Untreated (unprotected) specimens showed an increase in lambda value of 28 per cent after ten years; for materials protected with aluminium and metal-taped edges the increase was less than 5 per cent. One sample, namely PUR-foam covered completely with pvc using contact adhesive, revealed a higher increase in lambda value than the unprotected foam.
Temperature measurements of GaN FETs by means of average gate current sensing

Gallium Nitride is a promising technology to increase power density in future DC-DC converter. However, the size and volume of heat sinks and cooling equipment needed will limit the maximum achievable power density. Reducing the cooling effort for volume reduction of the heat sink is an option to increase the power density but requires good knowledge of the junction temperature to avoid overheating. The temperature dependent gate leakage of GaN FETs can be used to estimate the junction temperature during operation. This can be measured by observing the current supplied to the gate drive. The methodology shows how the average current supplied to the gate drive unit follows the device temperature.
Study of Alternative Strategies to the Task Clarification Activity of the Market-Pull Product Development Process Model

A very large majority of the current product development process models put forward in textbooks present a homogenous structure, what Ulrich & Eppinger [1] call the market-pull model, presented as a generic one, while other possible product development process models are merely seen as variants. This paper focuses on the task clarification and derived activities (mainly the systematic search for customer needs through market study and the supplementary development costs it entails) and investigates two alternative strategies that are not derived from the generic process model. The first alternative is the market-pull model without an extensive task clarification. The second is the application of the so-called expeditionary marketing strategy. With the help of simplified analytic modeling, the conditions for which these alternatives are as efficient as the generic process model are discussed. This advocates the development of more flexible process models. [1] Ulrich, K. T. and Eppinger, S. D. , 2008, Product Design and Development, 4th Edition, McGraw-Hill, London.
Speeding Up Full Syntactic Parsing by Leveraging Partial Parsing Decisions

Parsing is a computationally intensive task due to the combinatorial explosion seen in chart parsing algorithms that explore possible parse trees. In this paper, we propose a method to limit the combinatorial explosion by restricting the CYK chart parsing algorithm based on the output of a chunk parser. When tested on the three parsers presented in (Collins, 1999), we observed an approximate three-fold speedup with only an average decrease of 0.17% in both precision and recall.
Reasons for Quality Assurance in Higher Education • Examine the Challenges of Quality Higher Education in Nigeria • Discuss the Quality Assurance Variables in Higher Education in Nigeria

Nigeria like other countries of the world recognizes education as the major instrument for effecting national development. Education is a critical for social, economic and political development of Nigeria. These goals of education can be fully attained if quality delivery is rendered in higher education in Nigeria. Higher education of good quality is critical for Nigeria to become globally competitive. This article identified and discussed the challenges of quality in higher education in Nigeria in the 21 century. The author recommends that Nigerian government should meet up with the 26 per cent education spending as recommended by UNESCO. Besides, reform in existing higher education institutions in Nigeria can be attained via collaborative efforts between government and other sectors of Nigerian economy.