Experimental study on web crippling of lapped cold-formed steel channels subjected to interior two-flange loading

The current North American Specifications for the Design of Cold-Formed Steel (CFS) Structural Members, AISI-S136-01, specifies expressions for web crippling strength of different joist geometries in case of exterior end and concentrated load locations. However, it does not permit an in increase two-flange loading. Thus, the objective of this research in this thesis is to generate experimental data for CFS channels where both webs of channel members are lapped at the interior support location and being loaded simultaneously. This thesis summarizes the results of a parametric study to examine few parameters that affect web crippling strength of such lapped channels. These parameters include the unbraced length of channel member, the presence screws, the level of flange restraint at the interior support location, channel six and load bearing length (i.e. lap length). Test specimens were loaded to failure and load history and the failure pattern were recorded. Based on experimental findings, a reliable and economical design expression was developed for web crippling strength of lapped CFS channels at interior support location when subjected to two-flange loading.

Experimental study on web crippling of lapped cold-formed steel channels subjected to interior two-flange loading

The current North American Specifications for the Design of Cold-Formed Steel (CFS) Structural Members, AISI-S136-01, specifies expressions for web crippling strength of different joist geometries in case of exterior end and concentrated load locations. However, it does not permit an in increase two-flange loading. Thus, the objective of this research in this thesis is to generate experimental data for CFS channels where both webs of channel members are lapped at the interior support location and being loaded simultaneously. This thesis summarizes the results of a parametric study to examine few parameters that affect web crippling strength of such lapped channels. These parameters include the unbraced length of channel member, the presence screws, the level of flange restraint at the interior support location, channel six and load bearing length (i.e. lap length). Test specimens were loaded to failure and load history and the failure pattern were recorded. Based on experimental findings, a reliable and economical design expression was developed for web crippling strength of lapped CFS channels at interior support location when subjected to two-flange loading.

A PRIVATE MODEL OF INDEX IS A HINDRANCE OF STABILITY OF THE STATION OF ACCOMPANIMENT OF AIM OF ZENITHAL ROCKET COMPLEX OF SHORTER-RANGE

Protecting from the action of radio of hindrances on the elements of zenithal rocket complex of shorter-range is one of important problems, that requires modern approach for her decision. Presently, influence of active hindrances is certain yet not enough on possibilities of armament on the defeat of air aims. In the article the analysis of influence of hindrances of different closeness is conducted on the station of accompaniment of aims of fighting machine of zenithal rocket complex shorter-range. The partial model of determination of index is offered hindrance of stability of the station of accompaniment of aim of zenithal rocket complex of shorter-range. The brought partial model over allows an analytical method to conduct the evaluation of values of conditional hit of model aim probabilities under various conditions. Mathematical calculations are conducted for: amplification of aerial of accompaniment of aim of fighting machine and aerials factors hindrance of producer; powers of hindrances on the entrance of accompaniment of aim of fighting machine; to the maximum sensitiveness of accompaniment of aim of fighting machine and relations hindrance/noise in the radio-location channel of accompaniment of aim; standard deviation of error of aiming of rocket depending on distance to the point of meeting of rocket with an aim in the zone of defeat taking into account influence of hindrances on the radio-location channel of accompaniment of aim of fighting machine; probabilities of passing of rocket in the «tube» of the set radius and conditional hit of aim probability at firing by one rocket; coefficient of зпомеха stability of accompaniment of aim of fighting machine; to conditional hit of aim probability hindrance of producer at firing by two rockets. On the accepted entry informative parameters and technical descriptions of accompaniment of aim of fighting machine certainly her maximum sensitiveness and relation hindrance/noise in this radio-location channel. On results mathematical calculations (mathematical design) corresponding charts that over is brought are got. From charts it is possible to define high efficiency of firing rockets on a model (air) aim.

ThingsLocate: A ThingSpeak-Based Indoor Positioning Platform for Academic Research on Location-Aware Internet of Things

Seamless location awareness is considered a cornerstone in the successful deployment of the Internet of Things (IoT). Support for IoT devices in indoor positioning platforms and, vice versa, availability of indoor positioning functions in IoT platforms, are however still in their early stages, posing a significant challenge in the study and research of the interaction of indoor positioning and IoT. This paper proposes a new indoor positioning platform, called ThingsLocate, that fills this gap by building upon the popular and flexible ThingSpeak cloud service for IoT, leveraging its data input and data processing capabilities and, most importantly, its native support for cloud execution of Matlab code. ThingsLocate provides a flexible, user-friendly WiFi fingerprinting indoor positioning service for IoT devices, based on Received Signal Strength Indicator (RSSI) information. The key components of ThingsLocate are introduced and described: RSSI channels used by IoT devices to provide WiFi RSSI data, an Analysis app estimating the position of the device, and a Location channel to publish such estimate. A proof-of-concept implementation of ThingsLocate is then introduced, and used to show the possibilities offered by the platform in the context of graduate studies and academic research on indoor positioning for IoT. Results of an experiment enabled by ThingsLocate with limited setup and no coding effort are presented, focusing on the impact of using different devices and different positioning algorithms on positioning accuracy.

The Application of Axiomatic Design to Complex Wi-Fi Systems

Axiomatic Design is a technique that has been applied to multiple disciplines for enabling design, analysis, and troubleshooting of complex systems. In this paper, the principles of Axiomatic Design are applied to Wi-Fi networking. Wi-Fi is the information backbone for numerous applications, including Internet connectivity, video surveillance, data collection and inventory tracking in manufacturing and warehouse environments, patient location and health status monitoring in assisted living and hospital environments, along with numerous others. A Wi-Fi system consists of multiple access points working in tandem to provide seamless, high-speed, and high-quality wireless coverage to one or more wireless client devices. To implement such a network effectively, the Wi-Fi engineer must understand and control the interactions between multiple engineering disciplines, most notably information technology, network engineering, radio frequency physics, antenna design, and materials science. Technology development in this field is fast-paced, with new standards and capabilities being introduced into the market every couple of years. Additionally, the customer expectations (i.e. requirements) are changing as well once the Wi-Fi network is installed, as data demands from new types of devices like smartphones, tablets, and network appliances are introduced long after the original network was implemented. This paper shows that there are three primary functional requirements for a Wi-Fi network, namely client usage type, coverage area, and client capacity. When designing, implementing, or troubleshooting a Wi-Fi network, there are four primary design parameters that can be controlled, namely AP antenna / model, location, channel, and transmission power. Axiomatic Design demonstrates that these four design parameters are coupled, and thus cannot be manipulated independently. Nevertheless, by effectively implementing Axiomatic Design techniques to define a set of best practices, these four key parameters can be decoupled and properly linked back to the requirements and constraints of the system to simplify the design, implementation, and troubleshooting of a Wi-Fi network.