The role of high-altitude (Z > 200~~) tracer,stars in determining the Galactic disk potential is systematically analyzed. It is shown that such tracers cannot, by themselves, be used to measure the missing mass in the disk. Up to 60% of the disk mass may be in unobserved components with only a 20% discrepancy between the measured high-altitude disk potential and what could be expected from the ...

Exploiting spatial locality is critical for a disk scheduler to achieve high throughput. Because of the high cost of disk head seeks and the non-preemptible nature of request service, state-of-the-art disk schedulers consider the locality of both pending and future requests. Though schedulers adopting the approach, such as the anticipatory scheduler, show substantial performance advantages, the...

effects of four primary tillage machines on some properties of potato tubers     m .a ghazavi1, r . a mahmoodieh1* and a. khoddami2   1-assistant professor of agricultural machinery , islamic azad university, khorasgan branch, isfahan, iran.   2- technical assistant of food science and technology, islamic azad university, khorasgan branch, isfahan, iran.     received: accepted:     abstract   w...

In order to adapt to the requirements of the development for precision agriculture technology, making the rice seed tape planting technology has been widely used. The paper-making improved the design on the rice seed tape twisting machine especially the seed tape winding units. It proposed seed tape winding automatic control system based on STC90C514AD to realize the rotating speed adjustment o...

Cloud-assisted Cognitive Internet of Things has powerful data analytics abilities based on the computing and data storage capabilities of cloud virtual machines, which makes protecting virtual machine filesystem very important for the whole system security. Agentless periodic filesystem monitors are optimal solutions to protect cloud virtual machines because of the secure and low-overhead featu...

Optimization is often a question of where one should put one’s money in improving performance. As far as large storage hierarchies go, intuition suggests (and common practice supports) adding as much as is affordable of the fastest technology available. Many cache hierarchy studies have shown that this is often not the optimal approach, and we show that for mass storage hierarchies it always te...

Linear classification has demonstrated success in many areas of applications. Modern algorithms for linear classification can train reasonably good models while going through the data in only tens of rounds. However, large data often does not fit in the memory of a single machine, which makes the bottleneck in large-scale learning the disk I/O, not the CPU. Following this observation, Yu et al....

tillage and press wheel weight play an important role in seedling emergence, crop establishment and growth. an optimal combination of tillage implements and suitable press wheel weights should increase grain yield. this study investigated the effect of tillage systems and press wheel weights on dry land wheat (triticum aestivum l.) seedling emergence and grain yields in izeh, khuzestan province...

In virtual machine systems, with the increase in the number of VMs and the demands of the applications, the main memory is becoming a bottleneck for the application performance. To improve paging performance and alleviating thrashing behavior for memory-intensive or I/O-intensive virtual machine workloads, we proposed hypervisor based remote paging, which allows a virtual machine to transparent...