Injection-Limited and Space-Charge-Limited Conduction in Wide Bandgap Semiconductors with Velocity Saturation Effect

Carrier conduction in wide bandgap semiconductors (WBS) often exhibits velocity saturation at the high-electric field regime. How such effect influences the transition between contact-limited and space-charge-limited current in a two-terminal device remains largely unexplored thus far. Here, we develop a generalized carrier transport model that includes contact-limited field-induced carrier injection, space charge, carrier scattering and velocity saturation effect. The model reveals various transitional behaviors in the current-voltage characteristics, encompassing Fowler-Nordheim emission, trap-free Mott-Gurney (MG) SCLC and \emph{velocity-saturated SCLC}. Using GaN, 6H-SiC and 4H-SiC WBS as examples, we show that the velocity-saturated SCLC completely dominates the high-voltage ($10^2 \sim 10^4$ V) transport for typical sub-$\mu$m GaN and SiC diodes, thus unravelling velocity-saturated SCLC as a central transport mechanism in WBG electronics.Comment: 8 pages, 5 figure

Exceptional points in non-Hermitian Photonics: Applications and Recent Developments

Exceptional points are complex branching singularities of non-Hermitian bands that have lately attracted considerable interest, particularly in non-Hermitian photonics. In this article, we review some recent developments in non-Hermitian photonic platforms such as waveguides, photonic crystals, Fabry-Perot resonators and plasmonic systems, and suggest how optical non-linearities and exceptional bound states can significantly impact the development of non-Hermitian photonics in the near future

Universal Scaling and Signatures of Nodal Structures in Electron Tunneling from Two-Dimensional Semimetals

We present the theory of out-of-plane electron thermal-field emission from 2D semimetals. We show that the current($\mathcal{J}$)-field($F$)-temperature($T$) characteristic is captured by a universal scaling law applicable for broad classes of 2D semimetals, including monolayer and few-layer graphene, nodal point semimetals, nodal line semimetals and Dirac semimetals at the verge of topological phase transition. The low-temperature scaling takes the universal form, $\log\left( \mathcal{J}/F^\gamma \right) \propto -1/F$ with $\gamma = 1$ for 2D semimetals, which is in stark contrast to the classic Fowler-Nordheim scaling of $\gamma = 2$ for 3D metals. Importantly, the Fermi level dependence of the tunneling currents depends sensitively on the nodal structure through the electronic density of states, thus serving as a probe for detecting the various possible nodal structures of 2D semimetals. Our findings provide a theoretical basis for the understanding of tunneling charge transport phenomena in solid/vacuum and solid/solid interfaces, critical for the development of 2D-material-based vacuum and solid-state electronic devices.Comment: 8 pages, 2 figure

Working Capital Management Effect on the Performance of Wholesale and Property Industry in Malaysia

This paper provides the influence of working capital management (WCM) on the performance of public listed wholesale & retail industry and property industry in Malaysia from 2002 to 2011. Regression model is employed by using two measures of companies’ performance namely Return on Assets, ROA (proxy to gauge the firm’s profitability) and Tobin’s Q, TQ (proxy to gauge the firm’s market value) as the dependant variables. WCM components include Current Liabilities to Total Assets Ratio and Current Assets to Total Assets Ratio with three control variables which include of Firm Size (SIZE), Sales Growth (SLGR) and Financial Leverage (LEV) as the independent variables. The results to a very large extent indicate that CATAR and SIZE have significant positive effect on the performance of firm. It suggests that wholesale & retail industry and property industry in Malaysia should pursue unadventurous investment strategy by implementing high altitude of short term investment in order to make profit and create value for their shareholders. It also reveals that the larger the firms are, the more profitable they are; recommending the firms shall expand their business to achieve higher profit and accomplish shareholder wealth maximisation

Ultrasound-assisted extraction kinetics, fatty acid profile, total phenolic content and antioxidant activity of green solvents extracted passion fruit oil

The main objective of this current work was to evaluate the feasibility of green solvent's application on passion fruit oil extraction. In this study, the effects of green solvent on oil yield, fatty acid profile, oil physicochemical properties, total phenolic content and antioxidant activity associated with extracted oil were compared to those of conventional solvent, hexane application. Therefore, this study may provide supplementary information on previous studies that focused on oil recovery. Oilseeds' proximate composition and the influence of oilseeds-to-solvent (w/v) ratio on oil yield were investigated. The oilseeds contained high fibre, fat and protein. Oilseeds-to-solvent (w/v) ratio (1:8) provided the highest oil yield. Overall, acetone was suggested as a suitable hexane replacer due to its higher oil recovery, similar fatty acid profile and oil physicochemical properties with higher antioxidant activity. Ethanol-extracted oil contained higher amounts of omega-9 MUFA, which may indicate the influence of extraction solvent on final fatty acid composition and thus final oil application

Relationship between Macroeconomics and Stock Market: Empirical Study in Malaysia

This paper attempt to investigate the relationship between macroeconomic variables and FTSE Bursa Malaysia KLCI, the samples are divided into 2 groups such as foreign macroeconomic variables and local macroeconomic variables, foreign macroeconomic variables consist of Gold Bullion LBM price and Dow Jones Index, meanwhile local macroeconomic variables consist of Consumer Price Index, Base Lending Rate, Exchange Rate.This study employs data from Jan 2000 to Dec 2013 which contains a monthly data set of 168 observations. There are 3 methodologies used in this study to investigate the relationship, the first test is Unit Root test which used to test the stationary of each variable, the results indicate that all the variables are stationary in first difference, this is important to use stationary variables because if the variables are not stationary, it might lead to spurious regression. The second methodology is Johansen & Juselius Co-integration test to investigate the long run relationship among these variables, the results show that the foreign macroeconomic variables and local macroeconomic variables have long run relationship with KLCI and significant. Next, this study will investigate the short run relationship between macroeconomic variables and KLCI, the results indicate that Gold, BLR and CPI can granger cause KLCI and significant at 1%, 5% significance level respectively

Properties and morphology of poly(vinyl alcohol) blends with sago pith bio-filler as biodegradable composites

The effects of sago pith as a bio-filler (SPB) on the mechanical and thermal properties of poly(vinyl alcohol) (PVA) were studied. The SPB was obtained from sago pith waste after starch extraction from sago palm. Sago pith waste was dried and ground to produce SPB. The SPB was blended with PVA in a twin-screw co-rotating extruder in order to produce PVA-SPB composites for mechanical, morphology, and thermal analyses. Blending of SPB and PVA improved the tensile modulus, whereas the tensile strength was reduced. This result occurred because SPB increased the rigidity of PVA. However, lack of interfacial adhesion between PVA and SPB caused the loss of reinforcing effects. The morphology analysis showed that a high loading of SPB (>70 wt%) tended to form clusters, as implied by the presence of elongated cavities due to droplet coalescence restricting chain mobility. Besides that, the enthalpy of melting (Delta H(m)) for 50 wt% of SPB was higher than that of PVA. This observation means that the molecular interaction forces between PVA and SPB were so great as to overtake those of the PVA itself. Thus it was concluded that 40-50 wt% of SPB was preferably blended with PVA to form a biodegradable composite in order to reduce the overall materials cost, rather than to act as a strong reinforcing filler

Economics of neuraminidase inhibitor stock piling for pandemic influenza, Singapore.

We compared strategies for stock piling neuraminidase inhibitors to treat and prevent influenza in Singapore. Cost-benefit and cost-effectiveness analyses, with Monte Carlo simulations, were used to determine economic outcomes. A pandemic in a population of 4.2 million would result in an estimated 525-1,775 deaths, 10,700-38,600 hospitalization days, and economic costs of 0.7 dollars to 2.2 billion Singapore dollars. The treatment-only strategy had optimal economic benefits: stock piles of antiviral agents for 40% of the population would save an estimated 418 lives and 414 million dollars, at a cost of 52.6 million dollars per shelf-life cycle of the stock pile. Prophylaxis was economically beneficial in high-risk subpopulations, which account for 78% of deaths, and in pandemics in which the death rate was >0.6%. Prophylaxis for pandemics with a 5% case-fatality rate would save 50,000 lives and 81 billion dollars. These models can help policymakers weigh the options for pandemic planning

WeeliciousCuisine quick response (QR)

This paper attempts to create a WeeliciousCuisine quick respond (QR) code content which including some guideline video to guide the users on how to use this product and also providing some recipe to teach them how to used and how to made a complete dishes.The target of audience ages are in seventeen to twenty five years old.Besides that, it also aim for the restaurants, shops and bars to provide them a better understanding of how the products have been use as to improve the services of the tourism industry as this application provides the useful information related to the products or ingredients that required by the foreigners, so the users can get the right ingredients in overseas for example, Malaysia.Research conducted by using the descriptive statistics and result shown more than 58% respondents are still not familiar with Quick respond code but more than a half respondents are interested to know more about Quick respond code and requested to improve their content on food and beverage.In conclusion, WeeliciousCuisine Quick Response (QR) is a system that helps user to have a quick look and learn how to cook in short time.The function of this system is to prevent users for choosing the wrong ingredients and also help them to save time and cost in the supermarket

Solution enhanced dispersion by supercritical fluids (SEDS): an approach in particle engineering to modify aqueous solubility of andrographolide from Andrographis paniculata extract

The objective of study is to improve aqueous solubility of andrographolide through particle engineering using Solution Enhanced Dispersion by Supercritical Fluids (SEDS) approach. The precipitation pattern of sticky crude Andrographis paniculata extract from CO2-acetone system and CO2-acetone:ethanol (v/v) 1:1 system as well as the aqueous solubility of andrographolide precipitated were first studied at different pressure (100, 150 bar) and temperature (40, 50 °C) combination (full factorial design). The modification of aqueous solubility of andrographolide was then attempted by manipulating its precipitation process from CO2-solvent systems consisting of single solvent and solvent mixture at different proportions (v/v) at the appropriate pressure-temperature combination. A. paniculata powder precipitated from CO2-acetone system at 150 bar, 40 °C was found to be large, irregularly shaped, less crystalline with the highest andrographolide aqueous solubility (twofold increment compared to crude extract) and recovery compared to those precipitated from CO2-ethanol system and other CO2-solvent mixture systems. Complete dissolution of andrographolide from A. paniculata powder precipitated from CO2-acetone system had been achieved within 90 min. For SEDS precipitation under solvent mixture system, with increment of proportion of ethanol from 25% to 75%, larger particles and change of powder morphology from stripes into plates were resulted. Based on the higher aqueous solubility and dissolution of andrographolide, recovery as well as a different morphology observed from the less crystalline A. paniculata powder precipitated from CO2-acetone system, less impurities could have co-precipitated with andrographolide