Application of a simplified probe feed impedance formula to the design of a dual frequency patch antenna

A simplified probe feed input impedance for a rectangular patch antenna based on the Green's function is used to design a dual frequency matched antenna. The predicted results at design frequencies of 1.9 and 2.4 GHz are in close agreement with experimental measurements

An investigation into the effects of computer integrated manufacturing systems in the productivity of SMEs in Pakistan

The current dynamic and turbulent manufacturing environment has forced companies that compete globally to change their traditional methods of conducting business [Producer to consumer]. Recent developments in manufacturing and business operations have lead to the adoption of Computer Integrated Manufacturing (CIM) technologies that are based on systems and processes that support global competitiveness, especially for Small and Medium Enterprises (SMEs). Organizations and SMEs in particular need to re-evaluate every aspect of their manufacturing strategy and quickly move towards a CIM based environment where manufacturing technologies, business strategies and processes are integrated together. This paper highlights the development of a CIM adoption model that has resulted from empirical work generated from SMEs in Pakistan. The model consists of the parameters such as Top Management Support, System Integration, Marketing, and over all performance

Flow induced vibration of a square cylinder with high scruton number

Flow over a square cylinder is numerically studied to understand the effect of reduced velocity to the transverse oscillation under the influence of high Scruton number elastic system of 4.316. For low reduced velocities, the transverse oscillation behavior can be grouped in the initial branch region. In this region, the motion is mainly controlled by the lift fluctuation. For intermediate reduced velocities, the transverse oscillation behavior is grouped in the lower branch region. In this region, its natural frequency slowly becomes significant. For high reduced velocities, the galloping region is observed. In this region, the natural frequency dominated the shape of the amplitude oscillation

Yet another cause of chronic viral hepatitis?

The clinical features, course and histology of liver in 20 patients; mostly middle aged to elderly females, closely resembling chronic Non A Non B hepatitis is presented. They presented quite late in their disease and therefore, complications such as variceal bleeds, ascites and encephalopathy were frequent. Our patients were negative for hepatitis B and C virus serology. Metabolic and immune causes of chronic liver disease were also ruled out. To the best of our knowledge, this is the first study of its kind elaborating the clinical features, course and histology of liver in chronic Non B Non C hepatitis and raises a number of questions as to the nature of the infecting virus and the epidemiology of disease

Comparative study on energy extraction from vibrating square cylinder

In this paper, the prospect of harvesting energy from flow induced-vibration of a square cylinder is assessed. The extraction of energy from the flow is attained by mounting the square cylinder on a one-degree elastic system with a massdamping (m*ζ) of 2.75. OpenFOAM®, an open source CFD package is used to model the flow induced motion of the square cylinder. A theoretical formulation to estimate the lift force acting on the square cylinder is derived to confirm the results obtained by the simulation. A good agreement between the results is obtained. The amplitude vibration and lift force are then used to estimate the power induced by the oscillating square cylinder. Energy in the micro scale range can be harvested from this flow induced-vibration system. This type of alternative green energy is suitable for the micro energy harvester system required for sensors in many engineering structure for health monitoring purpose

Statistically Designed Bioprocess for Enhanced Production of Alkaline Protease in Bacillus cereus HP_RZ17

491-498Alkaline protease is one of the bulk enzymes having wide commercial demand for various applications. It is commercially produced by a submerged fermentation process employing various bacteria, Bacillus sp. being the most widely used species. Statistical optimization of the process for the production of alkaline proteases from rhizospheric bacteria and its application in the biocontrol of plant pathogens has not been explored fully and needs to be studied for the development of efficient bioprocess. We report the enhanced production of alkaline protease in the minimal salt medium (MSM) optimized using statistical approaches such as Plackett Burman Design (PBD) and Response Surface Methodology (RSM). In the first step; PBD, among the total eight variables, three variables namely, yeast extract (pppBacillus cereus HP_RZ17. These three variables were further analyzed in the second step i.e. Central Composite Design (CCD) of RSM. The optimum yield of alkaline protease by B. cereus HP_RZ17 (130.72 UmL-1) was obtained under the optimal conditions such as yeast extract (0.899% w/v), fructose (0.873% w/v), and pH (11.25) of production media. The statistically optimized values of variables used for the scale-up of the process at 5 L capacity bioreactor enhanced the alkaline protease yield (132.48 UmL-1) by 1.09 fold vis-à-vis un-optimized protocol (121.96 UmL-1) in B. cereus HP_RZ17

Vestibular Perception following Acute Unilateral Vestibular Lesions.

Little is known about the vestibulo-perceptual (VP) system, particularly after a unilateral vestibular lesion. We investigated vestibulo-ocular (VO) and VP function in 25 patients with vestibular neuritis (VN) acutely (2 days after onset) and after compensation (recovery phase, 10 weeks). Since the effect of VN on reflex and perceptual function may differ at threshold and supra-threshold acceleration levels, we used two stimulus intensities, acceleration steps of 0.5°/s(2) and velocity steps of 90°/s (acceleration 180°/s(2)). We hypothesised that the vestibular lesion or the compensatory processes could dissociate VO and VP function, particularly if the acute vertiginous sensation interferes with the perceptual tasks. Both in acute and recovery phases, VO and VP thresholds increased, particularly during ipsilesional rotations. In signal detection theory this indicates that signals from the healthy and affected side are still fused, but result in asymmetric thresholds due to a lesion-induced bias. The normal pattern whereby VP thresholds are higher than VO thresholds was preserved, indicating that any 'perceptual noise' added by the vertigo does not disrupt the cognitive decision-making processes inherent to the perceptual task. Overall, the parallel findings in VO and VP thresholds imply little or no additional cortical processing and suggest that vestibular thresholds essentially reflect the sensitivity of the fused peripheral receptors. In contrast, a significant VO-VP dissociation for supra-threshold stimuli was found. Acutely, time constants and duration of the VO and VP responses were reduced - asymmetrically for VO, as expected, but surprisingly symmetrical for perception. At recovery, VP responses normalised but VO responses remained shortened and asymmetric. Thus, unlike threshold data, supra-threshold responses show considerable VO-VP dissociation indicative of additional, higher-order processing of vestibular signals. We provide evidence of perceptual processes (ultimately cortical) participating in vestibular compensation, suppressing asymmetry acutely in unilateral vestibular lesions

A Guide for the Design of Benchmark Environments for Building Energy Optimization

The need for algorithms that optimize building energy consumption is usually motivated with the high energy consumption of buildings on a global scale. However, the current practice for evaluating the performance of such algorithms does not reflect this goal, as in most cases the performance is reported for one specific simulated building only, which provides no indication about the generalization of the score on other buildings. One approach to overcome this severe issue is to establish a shared collection of environments, each representing one simulated building setup, that would enable researchers to systematically compare and contrast the efficacy of their building optimization algorithms at scale. However, this requires that the individual environments are well designed for this goal. This paper is thus targeting the design of suitable environments for such a collection based on a detailed analysis of related publications that allows the identification of relevant characteristics for suitable environments. Based on this analysis a guide is developed that distills these characteristics into questions, intended to support a discussion of relevant topics during the design of such environments. Additional explanations and examples are provided for each question to make the guide more comprehensible. Finally, it is demonstrated how the guide can be applied, by utilizing it for the design of a novel environment, which represents an office building in tropical climate. This environment is released open source alongside this publication. We also indicate how test scenarios from existing publications could be enhanced to comply with the required characteristics according to our guide, underlining its importance for the future development and evaluation of building energy optimization algorithms, and thus for the sustainability of buildings in general

Access and utilisation of primary health care services comparing urban and rural areas of Riyadh Providence, Kingdom of Saudi Arabia

The Kingdom of Saudi Arabia (KSA) has seen an increase in chronic diseases. International evidence suggests that early intervention is the best approach to reduce the burden of chronic disease. However, the limited research available suggests that health care access remains unequal, with rural populations having the poorest access to and utilisation of primary health care centres and, consequently, the poorest health outcomes. This study aimed to examine the factors influencing the access to and utilisation of primary health care centres in urban and rural areas of Riyadh province of the KSA