808 research outputs found
Implementing family involvement in the treatment of patients with psychosis: a systematic review of facilitating and hindering factors
This paper presents independent research and was partially funded by the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care (NIHR CLAHRC) North Thames at Bart's Health NHS Trust
Performance Analysis of NAND Flash Memory Solid-State Disks
As their prices decline, their storage capacities increase, and their endurance improves, NAND Flash Solid-State Disks (SSD) provide an increasingly attractive alternative to Hard Disk Drives (HDD) for portable computing systems and PCs. HDDs have been an integral component of computing systems for several decades as long-term, non-volatile storage in memory hierarchy. Today's typical hard disk drive is a highly complex electro-mechanical system which is a result of decades of research, development, and fine-tuned engineering. Compared to HDD, flash memory provides a simpler interface, one without the complexities of mechanical parts. On the other hand, today's typical solid-state disk drive is still a complex storage system with its own peculiarities and system problems.
Due to lack of publicly available SSD models, we have developed our NAND flash SSD models and integrated them into DiskSim, which is extensively used in academe in studying storage system architectures. With our flash memory simulator, we model various solid-state disk architectures for a typical portable computing environment, quantify their performance under real user PC workloads and explore potential for further improvements. We find the following:
* The real limitation to NAND flash memory performance is not its low per-device bandwidth but its internal core interface.
* NAND flash memory media transfer rates do not need to scale up to those of HDDs for good performance.
* SSD organizations that exploit concurrency at both the system and device level improve performance significantly.
* These system- and device-level concurrency mechanisms are, to a significant degree, orthogonal: that is, the performance increase due to one does not come at the expense of the other, as each exploits a different facet of concurrency exhibited within the PC workload.
* SSD performance can be further improved by implementing flash-oriented queuing algorithms, access reordering, and bus ordering algorithms which exploit the flash memory interface and its timing differences between read and write requests
Some Result on Contact Pseudo-Slant Submanifolds of a Sasakian Manifold
In this paper, we study the geometry of the contact pseudo-slant submanifolds of a Sasakian manifold. We derive the integrability conditions of distributions in the definition of a contact pseudo-slant submanifold. The notions contact pseudo-slant product is defined, and the necessary and sufficient conditions for a submanifold to contact pseudo-slant product is given. Also, a non-trivial example is used to demonstrate that the method presented in this paper is effective
Maximizing Strike Planning Efficiency for a Given Class of Targets
Strike planning is one of the fundamental tasks of the Turkish Air Force and involves assignment of strike aircraft to targets with a maximum level of efficiency. Therefore, planning an optimal strike plan based on the preferences of the decision maker is crucial. The efficiency of the strike plan in this research implies attacking the maximum number of targets while considering target priority and the desired level of damage on each target. Another objective is to minimize the cost of the plan. This research develops an exact model that maximizes the efficiency of the strike plan using LINGO with Excel Spreadsheets. Given this efficiency, the aircraft and weapon costs plus the distance own is minimized while maintaining efficiency. The model also takes into account the aircraft and weapon capacities for particular types at each base to avoid assigning aircraft to targets from a base where there is an insufficient resource in terms of the aircraft and weapon capacity. The results show that the model developed in this research provides a great deal of cost saving (i.e., approximately 50 %) for a strike plan compared to a strike plan which does not consider the total cost
Approximation for periodic functions via statistical σ-convergence
In this study, using the concept of statistical σ-convergence which is stronger than convergence and statistical convergence we prove a
Korovkin-type approximation theorem for sequences of positive linear
operators defined on which is the space of all -periodic and continuous functions on , the set of all real numbers. We also study the rates of statistical σ-convergence of approximating positive linear operators
Modified double Szász-Mirakjan operators preserving
In this paper, we introduce a modification of the Sz\u27{a}sz-Mirakjan type operators of two variables which preserve and We prove that this type of operators enables a better error estimation on the interval than the classical Sz\u27{a}sz-Mirakjan type operators of two variables. Moreover, we prove a Voronovskaya-type theorem
and some differential properties for derivatives of these modified
operators. Finally, we also study statistical convergence of the sequence of modified Sz\u27{a}sz-Mirakjan type operators
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