The Infrared Data Association (IrDA) Advanced Infrared (AIr) protocol for indoor optical wireless LANs is examined. AIr Medium Access Control (MAC) layer utilizes a Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) scheme to coordinate medium access. To deal with hidden stations, AIr employs a Request To Send / Clear To Send (RTS/CTS) reservation scheme and a long Collision Avoid...

A simulation model for the proposed IrDA Advaned Infrared (AIR) protocol is developed. Throughpt performance of AIr's Reserved mode, which employes an RTS/CTS reservation scheme, is explored. The importance of the CAS window size parameter for different network sizes is presented in relation to the large Slot Time value proposed by the AIr standard. The effectiveness of the proposed adaptive Co...

vibration in the air slide tables of ultra precision machines prevents gaining accuracies within nanometer level. in this work, dissimilar types of internal vibration including small vibrations and pneumatic hammers have been tested and some measures have been offered to reduce their effects. this paper has also proceeded to the vibration tests on the air slide tables built with different numbe...

Fabrication of air filtration materials (AFM) that allow air to easily flow through while retaining particles is a significant and urgent need due to the harmful airborne particulate matter pollution; however, this is still a challenging research area. Herein, we report novel slip-effect functional nanofibrous membranes with decreased air resistance (reduction rate of 40%) due to the slip flow ...

The inter-comparison of regional air quality models is an effective way to understand uncertainty in ambient pollutant concentrations simulated using various model configurations, as well as to find ways to improve model performance. Based on the outcomes and experiences of Japanese projects thus far, a new model inter-comparison project called Japan’s study for reference air quality modeling (...

Prolonged air leakage is a major cause of morbidity in pneumothorax. When conservative management is not effective, surgery should be performed. However, surgery is not appropriate in patients with low pulmonary function. In these patients, occlusion of the airway with endobronchial blockers may be attempted under bronchoscopy. We treated two patients with prolonged air leakage using endobronch...

In this paper the dispersion property of index guided photonic crystal fibers (PCFs) of silica material has been investigated. The modal analysis is done to obtain the complex effective refractive index for: (i) Hexagonal lattice with circular air holes and first ring having elliptical cells (ii) Rectangular lattice with circular air holes and first ring having elliptical cells. The dispersion

in this study, mathematical modeling of hot air-drying of thin-layer papaya (carica papaya l.) slices with 5±1 mm thickness pretreated in osmotic solution (50% sucrose) was investigated. thin-layer drying was conducted under three different drying temperatures of 40, 50 and 60 °c at a constant air velocity of 0.9±0.1 m/s and absolute humidity of 0.6 ± 0.02 g of water/kg of dry air. it was found...

this paper describes the theoretical and experimental investigations of the key components and also the performance analysis of a rotary wheel for using as a solid desiccant dehumidifier and also indirect evaporator cooling system. solid desiccants have long been used in dehumidification and cooling systems for energy efficiency or reduce electricity. although many mathematical models on the ro...