Heat dissipation, thermal stresses, size and cost are the key packaging design issues for electronic and optoelectronic instruments. As per defense requirement, instruments are expected to work satisfactorily in the temperature range of -30C to +55C. In this study, we have explored the thermal management of a sealed enclosure, envisaged as housing for handheld instruments, using different activ...

The intention of this article is to compare the containment performance of a Type II microbiological safety cabinet (MSC) confronted with the simultaneous generation of a saline nanoparticle aerosol and a tracer gas (SF(6)). The back dissemination coefficient, defined as the ratio of the pollutant concentration measured outside the enclosure to the pollutant flow rate emitted inside the enclosu...

Most portable diesel generators (often referred to as gensets) produce high sound power levels. The sound generated by various internal components of the genset is transmitted to the far field by two radiation mechanisms: sound transmits through the panels of the generator enclosure as well as propagates through any openings in the enclosure. In order to determine which mechanism to control, a ...

Contemporary design of large telescopes requires optimization of the telescope environment in order to fully realize the capabilities of advanced mirror technology, telescope control and instrumentation. Telescope enclosure design is a critical element in providing this optimized environment. Enclosures must protect the telescope while minimizing the local degradation of image quality, and the ...

Applying shielding coils is a practical way to protect current transformers (CTs) for large-capacity generators from the intensive magnetic interference produced by adjacent bus-bars. The aim of this study is to build a simple analytical model for the shielding coils, from which the optimization of the shielding coils can be calculated effectively. Based on an existing stray flux model, a new a...

In this article, mixed convection heat transfer of alumina-water nanofluid in an inclined and baffled C-shape enclosure is studied. It is assumed that the flow is laminar and steady. There is no energy production, energy storage and viscous heat dissipation. Furthermore, the nanofluid is considered as a continuous, Newtonian and incompressible fluid. Governing equations are discretized by finit...

Background: Gonad shielding has been recommended during pelvic x-rays since the 1950s. The popular method of gonad shielding is placement a lead shield in the midline of the pelvis. The aim of this study was to evaluate the prevalence and utility of gonad shielding in pediatrics undergoing pelvic x-rays.Materials and MethodsFollowing study approval, we retrospectively retrieved data from the di...

Background: The Shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. These methods include Lead standard blocks, individual molding and multi leaf collimator (MLC). The MLC method is not still common in Iran radiotherapy centers. Individual molding is better than the lead block shield...

The primary purpose of this report is to review the general principles of shielding during computed tomography (CT) and to summarize the latest published information on shielding efficacy. Currently, there are discordant opinions within the literature regarding the appropriateness of shielding, particularly with regard to in-plane bismuth. Understanding that the decision to implement use of a p...

In this paper, it is demonstrated how anisotropic and inhomogeneous magnetic metamaterials may be used for molding the flow of the magnetic field, considering magnetic field shielding as the main application of practical interest. It is shown that using anisotropic materials, magnetic field shielding may be improved, and this anisotropy can be realized by metamaterials. Introducing additional i...