Many microorganisms swim in a highly heterogeneous environment with obstacles such as fibers or polymers. To better understand how this environment affects microorganism swimming, we study propulsion of a cylinder or filament in a fluid with a sparse, stationary network of obstructions modeled by the Brinkman equation. The mathematical analysis of swimming speeds is investigated by studying an ...

Four embryonic bigeye thresher sharks Alopias superciliosus (126–158 cm total length) were collected from two females caught by bottom set gillnet and hook and line (operating in 120–800 m depth) caught from off Kanyakumari area and landed in Cochin Fisheries Harbour on 11-06-2012 . Detailed morphometric measurements are provided. The ratio of size at birth (Lb) and maximum observed length (L m...

Harvest and post-harvest operations constitute principal constraints to rice production, especially in irrigated systems, because of the larger yield that has to be handled. Post-harvest crop losses of up to 35% have been reported and attributed to inefficiency of manual threshing of rice by small-scale farmers. This leads to poor grain quality and rejection of locally produced rice. The Africa...

We consider the dynamics of a hollow cylindrical shell that is filled with viscous fluid and another, nested solid cylinder, and allowed to roll down an inclined plane. A mathematical model is compared to simple experiments. Two types of behaviour are observed experimentally: on steeper slopes, the device accelerates; on shallower inclines, the cylinders rock and roll unsteadily downhill, with ...

honing is a process for finishing surfaces to obtain smooth surface. this process is used for finalpolish of inner parts such as engines cylinders. optimizing this process has always been a bigchallenge for mass production of cylinder blocks of internal combustion engines. honing processhas some variable parameters, thus to get their optimum rates the automobile cylinders were tested.in this re...

The working process of marine diesel engine is simulated by combining mean value engine model and volumetric model. It reflects some average parameters such as effective pressure, effective power and engine speed, as well as reflects real-time explosion pressure, maximum temperature in cylinder and indicator diagram. In order to accelerate the simulation, Crank Angle and cylinder pressure is im...

cumin is an annual plant suitable for dry and semi-dry regions. it is harvested at two stages to prevent seed shedding. first, the cumin bushes are harvested by hand or using a scythe. after drying, the cumin bushes are beaten with a stick or trampled using animals or a small tractor. this harvesting method is time consuming, requires intensive labor and is an incomplete threshing process resul...

This thesis describes the results of over 2000 experimental runs conduced at the MIT Ship Model Testing Tank. A rake of constant temperature anemometers is employed to study the spanwise velocity correlation and the vertical velocity profile downstream of a vibrating cylinder. Experiments involve either free vibration implemented through a force feedback system or forced sinusoidal motion. All ...

Pressure and performance requirements of axial piston pumps and the proportion of churning losses in axial piston pumps increase significantly with increasing speed. To investigate the primary distribution of churning losses in axial piston pumps at various ranges of speed, a test rig was set up in which other friction losses can be eliminated, thus making it possible to investigate the net chu...

Fishes with internalized and endothermic red muscles (i.e. tunas and lamnid sharks) are known for a stiff-bodied form of undulatory swimming, based on unique muscle-tendon architecture that limits lateral undulation to the tail region even though the red muscle is shifted anteriorly. A strong convergence between lamnid sharks and tunas in these features suggests that thunniform swimming might b...