An analysis of the effect of orientation on the heat transfer in a scaled model pin fin heat sink utilized in Light Emitting Diode (LED) lighting has been carried out using numerical method. The present study involves natural convective heat transfer that takes place in particular heat sink. A pin fin type heat sink has been studied since they are widely used in LED lighting systems which in tu...

Wireless sensor networks commonly consist of a large number of tiny sensor nodes that are deployed either inside the target area or very close to it to cooperatively monitor the target area. Energy efficiency and network lifetime are two challenges that most of researchers deal with. In this paper, to improve the performance of sensor networks, we propose an energyefficient competitive clusteri...

Mechanisms that allow plants to cope with a recurrent surplus of carbon in conditions of imbalance between source and sink activity has not received much attention. The response of sink growth and metabolism to the modulation of source activity was investigated using elevated CO(2) and elevated O(3) growth conditions in Erythronium americanum. Sink activity was monitored via slice and mitochond...

The world’s ocean and land ecosystems act as sinks for anthropogenic CO2, and over the last half century their combined sink strength grew steadily with increasing CO2 emissions. Recent analyses of the global carbon budget, however, have uncovered an abrupt, substantial (∼ 1 PgC yr) and sustained increase in the land sink in the late 1980s whose origin remains unclear. In the absence of this pr...

In this experiment, we investigated the performance of two types of heat sink, swagedand extruded-type, used in the inverter of industrial electricity generator. The swaged-type heat sink has 62 fins, and the extruded-type has 38 fins having the same dimension as that of the swaged-type. But the extruded-type heat sink maintains the same heat transfer area by the laterally waved surface which h...

Wireless sensor and actor networks (WSANs) consist of three components which are sensor nodes, actor nodes and central controller (sink). The act of sensors is gathering data from the physical environment and sending them to the actor or the sink. The actors react according to received data from the sensor or the sink. After detection of an event, this data must be sent to the sink or actor imm...

At present, many researchers concentrate on the researches of sink mobility and propose a lot of efficient data harvesting algorithms for wireless sensor networks (WSNs). In general, these algorithms mainly formulate their ideas in two ways, namely path-controllable and path-constrained sink mobility. In most application scenarios of WSNs, mobile sink is path-constrained and a big challenge of ...

In this paper, we consider a heterogeneous power network (HPN) where an electric-supplied sink uses much higher transmission power than battery-supplied nodes. The HPN potentially enables the sink to directly cover the whole area (i.e., all nodes are within one hop transmission range of the sink). Based on the characteristics, we design a fast and light collection protocol (FLC). FLC allows the...

In a wireless sensor network where sensors are arranged into a flat topology, sensors near the sink consume much more energy than sensors at the boundary of the network. Sensors near the sink relay many packets than far away sensors to the sink. After these sensors expire, energy holes are created near the sink. Therefore, other sensors cannot reach to the sink and the network becomes disconnec...

While batteries offer electronic source and sink for electronic devices, atomic analogues of source and sink and their theoretical descriptions have been a challenge in cold-atom systems. Here we consider dynamically emerged local potentials as controllable source and sink for bosonic atoms. Although a sink potential can collect bosons in equilibrium and indicate its usefulness in the adiabatic...