2,621 research outputs found
EAST: Energy Efficient Adaptive Scheme for Transmission in Wireless Sensor Networks
In this paper, we propose Energy-efficient Adaptive Scheme for Transmission
(EAST) in WSNs. EAST is IEEE 802.15.4 standard compliant. In this approach,
open-loop is used for temperature-aware link quality estimation and
compensation. Whereas, closed-loop feedback helps to divide network into three
logical regions to minimize overhead of control packets on basis of Threshold
transmitter power loss (RSSIloss) for each region and current number of
neighbor nodes that help to adapt transmit power according to link quality
changes due to temperature variation. Simulation results show that propose
scheme; EAST effectively adapts transmission power to changing link quality
with less control packets overhead and energy consumption compared to classical
approach with single region in which maximum transmitter power assigned to
compensate temperature variation
Simulation Analysis of Medium Access Techniques
This paper presents comparison of Access Techniques used in Medium Access
Control (MAC) protocol for Wireless Body Area Networks (WBANs). Comparison is
performed between Time Division Multiple Access (TDMA), Frequency Division
Multiple Access (FDMA), Carrier Sense Multiple Access with Collision Avoidance
(CSMA/CA), Pure ALOHA and Slotted ALOHA (S-ALOHA). Performance metrics used for
comparison are throughput (T), delay (D) and offered load (G). The main goal
for comparison is to show which technique gives highest Throughput and lowest
Delay with increase in Load. Energy efficiency is major issue in WBAN that is
why there is need to know which technique performs best for energy conservation
and also gives minimum delay.Comment: NGWMN with 7th IEEE International Conference on Broadband and
Wireless Computing, Com- munication and Applications (BWCCA 2012), Victoria,
Canada, 201
The Overshot Gate as a Flow-Measuring Device
The overshot gate is a commonly used adjustable overflow weir for regulating the upstream water level in open channels. The amount of gate movement is proportional to the water level change. However, to effectively manage the water flow, it is also important for operators to accurately measure the flow rate in the channel. This study examines an overshot gate installed at the end of a laboratory flume to estimate the flow rate under various free flow conditions. This study investigates different gate angles ranging from 9.6° to 90° to evaluate their impact on the flow properties and the discharge coefficient. The analysis of the results indicates that the maximum flow rate values can be achieved with gate inclinations from 15.5° to 47.2° with relatively lower head; the inclined alignment of the gate decreases the effective gate height which consequently increases the gate efficiency. The use of the overshot gate is advantageous over the normal gate when channel depth is limited and higher discharge is required at relatively lower head. In this study, at the highest gate inclinations, the water surface is significantly stable having the lowest values of the approach Froude number. In addition, the head to gate height ratio decreases with raising the gate due to the reduced vertical contraction of the channel. Finally, this paper proposes an empirical equation for estimating the discharge coefficient based on the gate inclination, which demonstrates good accuracy in the specified range
Going Beyond Equations With Disciplinary Thinking In First-Year Physics
Students in first-year physics courses generally focus on hunting for suitable equations and formulas when tackling a variety of physical situations and physics problems. There is a need for a framework that can guide them to disciplinary ways of thinking and help them begin to think like physicists. To serve this end, in this study, a framework of disciplinary thinking in physics was presented to the students and incorporated in the delivery of a first-year course on electricity and magnetism for engineering students. The framework consisted of three types of thinking: principle-based thinking (PBT), case-based thinking (CBT), and experiential-intuitive thinking (EIT). The students’ experiences of learning this framework were tracked through weekly reflection reports, which were analyzed using a coding scheme comprised of the following four categories of increasing cognitive complexity for each type of thinking: mentioning the type of thinking learned without elaboration (code A), mentioning the type of thinking learned with elaboration (code B), applying the type of thinking learned (code C) and making meaning of the type of thinking learned (code D). Examples of students’ reflections for these codes for each type of thinking are included. The students most predominantly reflected on PBT followed by CBT with a very few reflections on EIT. Within both PBT and CBT, most reflections fell under the code B. Overall, the results are encouraging and point to a students’ shift from formula hunting to the thinking framework based strategies
Estimate and Classify the Hardness of Different Water Sources by Using Prepared Soap Solution
This research includes available techniques and simplified methods to estimate and classify the quality of hardness for different water supply sources like sea water, various wells (Fayda, khabyar, jumbyar) and tap water of Basrah ,Mosul, Duhok and Baghdad, by using prepared soap solution from different commercial liquid soap with different concentration (SS1,2,3 , SS4,5,6 , SS7,8,9 ). The hardness of water is relative to the formation of foam (suds) when soap solution is added to water samples until a foam layer of a certain height (2cm) formed. We determine the volume (in drops, milliliter) of soap solution. If there is a lot of foam formed quickly with little soap solution, the water is rather soft. If you need to add a lot of soap solution to produce a certain height of foam, the water is rather hard. Many factor that establish during experiments, the quality of water supply, measuring degree of hardness, concentration of water samples. Compared with the results of laboratory tests for water stations of Mosul gave our method of encouraging and positive results to continue in the future, so liquid soap bubbles (foam) are a good indicator of classifying types of water. Key words: Estimate and classify the hardness of different water sources, New and simple calculationsÂ
Performance Analysis of Hierarchical Routing Protocols in Wireless Sensor Networks
This work focusses on analyzing the optimization strategies of routing
protocols with respect to energy utilization of sensor nodes in Wireless Sensor
Network (WSNs). Different routing mechanisms have been proposed to address
energy optimization problem in sensor nodes. Clustering mechanism is one of the
popular WSNs routing mechanisms. In this paper, we first address energy
limitation constraints with respect to maximizing network life time using
linear programming formulation technique. To check the efficiency of different
clustering scheme against modeled constraints, we select four cluster based
routing protocols; Low Energy Adaptive Clustering Hierarchy (LEACH), Threshold
Sensitive Energy Efficient sensor Network (TEEN), Stable Election Protocol
(SEP), and Distributed Energy Efficient Clustering (DEEC). To validate our
mathematical framework, we perform analytical simulations in MATLAB by choosing
number of alive nodes, number of dead nodes, number of packets and number of
CHs, as performance metrics.Comment: NGWMN with 7th IEEE International Conference on Broadband and
Wireless Computing, Communication and Applications (BWCCA 2012), Victoria,
Canada, 201
The effects of poverty and prison on British Muslim men who offend
© 2018 by the author. Focusing on the lives of British Muslim young men, this article examines the links between their social and economic relations and their prison experiences, desistance, and identity. In understanding the meanings they place on their prison experiences and their social and economic marginalization, the article theorises about social integration, and their place in British society. An intergenerational shift from the availability of local high-waged, skilled, and secure textile work to low-waged, precarious, service work presented them with a series of problems and opportunities, leading them to reject licit wage labour and embrace illicit entrepreneurial criminality. The article concludes that their social and economic relations drove criminal solutions, not ethnicity
Transmission Delay of Multi-hop Heterogeneous Networks for Medical Applications
Nowadays, with increase in ageing population, Health care market keeps
growing. There is a need for monitoring of Health issues. Body Area Network
consists of wireless sensors attached on or inside human body for monitoring
vital Health related problems e.g, Electro Cardiogram (ECG),
ElectroEncephalogram (EEG), ElectronyStagmography(ENG) etc. Data is recorded by
sensors and is sent towards Health care center. Due to life threatening
situations, timely sending of data is essential. For data to reach Health care
center, there must be a proper way of sending data through reliable connection
and with minimum delay. In this paper transmission delay of different paths,
through which data is sent from sensor to Health care center over heterogeneous
multi-hop wireless channel is analyzed. Data of medical related diseases is
sent through three different paths. In all three paths, data from sensors first
reaches ZigBee, which is the common link in all three paths. After ZigBee there
are three available networks, through which data is sent. Wireless Local Area
Network (WLAN), Worldwide Interoperability for Microwave Access (WiMAX),
Universal Mobile Telecommunication System (UMTS) are connected with ZigBee.
Each network (WLAN, WiMAX, UMTS) is setup according to environmental
conditions, suitability of device and availability of structure for that
device. Data from these networks is sent to IP-Cloud, which is further
connected to Health care center. Main aim of this paper is to calculate delay
of each link in each path over multihop wireless channel.Comment: BioSPAN with 7th IEEE International Conference on Broadband and
Wireless Computing, Communication and Applications (BWCCA 2012), Victoria,
Canada, 201
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