─ This paper deals with an impact of receiving antenna placed in a metal enclosure on an electromagnetic field distribution within the enclosure, and thus on its shielding effectiveness. In an experimental setup, a frequently used tool for measuring the electromagnetic field level at certain points within the enclosure is a dipole antenna connected to a measuring instrument via a coaxial cable....

This paper presents a new version of the upwind compact finite difference scheme for solving the incompressible Navier-Stokes equations in generalized curvilinear coordinates. The artificial compressibility approach is used, which transforms the elliptic-parabolic equations into the hyperbolic-parabolic ones so that flux difference splitting can be applied. The convective terms are approximated...

Department of Mechanical Engineering, The Hong Kong Polytechnic University Hung Home, Kowloon, Hong Kong, SAR of China Email address: [email protected]. Abstract This paper examines the influence of the internal resistance of a Helmholtz resonator on the noise control in a small enclosure. The absorptive process mainly occurring within the neck of a Helmholtz resonator provides the resonator w...

in the present study, mixed convection laminar flow around an adiabatic body in a lid-driven enclosure filled with nanofluid using variable thermal conductivity and variable viscosity is numerically investigated. the fluid around the body in the enclosure is a water-based nanofluid containing al2o3 nanoparticles. the vertical enclosure’s walls are maintained at constant cold temperature and the...

The portable generators are the main means of compensating the shortage of national electricity power as in Iraq. However, their noise causes a huge disturbance, uncomforting and loss of concentration of the nearby resident. This problem requires a solution because most shops and residential houses use generators. Covering method is a simple and relatively low cost one for reduction of generato...

Three enclosures (10 x 10 x 1.5-1.3 m in depth) were set beside Dianch Lake, Kunming, People's Republic of China, for the period from July 28 to August 26, 2002. The enclosures were filled with cyanobacterial (Microcystis aeruginosa) water bloom-containing lake water. Lake sediment that contained macrophytes and water chestnut seeds was spread over the entire bottom of each enclosure. Initially...

livestock grazing is one of the most important kinds of land usage that has a high potential to decrease or increase carbon storage in rangeland ecosystem. this research was investigated the effects of enclosure on soil carbon storage in a rangeland with dominant plants of artemisia aucheri. hence, two rangelands of enclosure (shahtappeh-chah mahmood) and no enclosure (chiro) were chosen in sem...

Based on the necessity for enclosure protection of temperature and relative humidity sensors installed in a hostile environment, a wind tunnel was used to quantify the time that the sensors take to reach equilibrium in the environmental conditions to which they are exposed. Two treatments were used: (1) sensors with polyvinyl chloride (PVC) enclosure protection, and (2) sensors with no enclosur...

At present advanced projects of the early XXI century are beginning to develop. These projects include lunar base development and manned missions to Mars. The space suit is one of the basic requirements for successful implementation of future programs. The space suit enclosure enables mobility of crewmembers wearing pressurized space suits which will be required to complete these missions. Requ...

The epiboly of the Caenorhabditis elegans hypodermis involves the bilateral spreading of a thin epithelial sheet from the dorsal side around the embryo to meet at the ventral midline in a process known as ventral enclosure. We present evidence that ventral enclosure occurs in two major steps. The initial migration of the hypodermis is led by a quartet of cells, which exhibit protrusive activity...