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Sequence Step Algorithm
A sequence step algorithm (SQS-AL) is an algorithm implemented in a discrete event simulation system to maximize resource utilization. This is achieved by running through two main nested loops: A sequence step loop and a replication loop. For each sequence step, each replication loop is a simulation run that collects crew idle time for activities in that sequence step. The collected crew idle times are then used to determine resource arrival dates for user-specified confidence levels. The process of collecting the crew idle times and determining crew arrival times for activities on a considered sequence step is repeated from the first to the last sequence step. See also * Computational resource * Linear scheduling method Linear scheduling method (LSM) is a graphical scheduling method focusing on continuous resource utilization in repetitive activities. Application LSM is used mainly in the construction industry to schedule resources in repetitive activities comm ... Referenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can perform automated deductions (referred to as automated reasoning) and use mathematical and logical tests to divert the code execution through various routes (referred to as automated decision-making). Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus". In contrast, a Heuristic (computer science), heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. As an effective method, an algorithm ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discrete Event Simulation
A discrete-event simulation (DES) models the operation of a system as a (discrete) sequence of events in time. Each event occurs at a particular instant in time and marks a change of state in the system. Between consecutive events, no change in the system is assumed to occur; thus the simulation time can directly jump to the occurrence time of the next event, which is called next-event time progression. In addition to next-event time progression, there is also an alternative approach, called incremental time progression, where time is broken up into small time slices and the system state is updated according to the set of events/activities happening in the time slice. Because not every time slice has to be simulated, a next-event time simulation can typically run faster than a corresponding incremental time simulation. Both forms of DES contrast with continuous simulation in which the system state is changed continuously over time on the basis of a set of differential equations def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System Resource
In computing, a system resource, or simple resource, is any physical or virtual component of limited availability within a computer system. All connected devices and internal system components are resources. Virtual system resources include files (concretely file handles), network connections (concretely network sockets), and memory areas. Managing resources is referred to as resource management, and includes both preventing resource leaks (not releasing a resource when a process has finished using it) and dealing with resource contention (when multiple processes wish to access a limited resource). Computing resources are used in cloud computing to provide services through networks. Major resource types * Interrupt request (IRQ) lines * Direct memory access (DMA) channels * Port-mapped I/O * Memory-mapped I/O * Locks * External devices * External memory or objects, such as memory managed in native code, from Java; or objects in the Document Object Model (DOM), from JavaSc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Flow
In computer science, control flow (or flow of control) is the order in which individual statements, instructions or function calls of an imperative program are executed or evaluated. The emphasis on explicit control flow distinguishes an ''imperative programming'' language from a '' declarative programming'' language. Within an imperative programming language, a ''control flow statement'' is a statement that results in a choice being made as to which of two or more paths to follow. For non-strict functional languages, functions and language constructs exist to achieve the same result, but they are usually not termed control flow statements. A set of statements is in turn generally structured as a block, which in addition to grouping, also defines a lexical scope. Interrupts and signals are low-level mechanisms that can alter the flow of control in a way similar to a subroutine, but usually occur as a response to some external stimulus or event (that can occur asynchronously), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idle (CPU)
A computer processor is described as idle when it is not being used by any program. Every program or task that runs on a computer system occupies a certain amount of processing time on the CPU. If the CPU has completed all tasks it is idle. Modern processors use idle time to save power. Common methods are reducing the clock speed along with the CPU voltage and sending parts of the processor into a sleep state. On processors that have a halt instruction that stops the CPU until an interrupt occurs, such as x86's HLT instruction, it may save significant amounts of power and heat if the idle task consists of a loop which repeatedly executes HLT instructions. Many operating systems, for example Windows, Linux, and macOS will run an idle task, which is a special task loaded by the OS scheduler on a CPU when there is nothing for the CPU to do. The idle task can be hard-coded into the scheduler, or it can be implemented as a separate task with the lowest possible priority. An advantag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computational Resource
In computational complexity theory, a computational resource is a resource used by some computational models in the solution of computational problems. The simplest computational resources are computation time, the number of steps necessary to solve a problem, and memory space, the amount of storage needed while solving the problem, but many more complicated resources have been defined. A computational problem is generally defined in terms of its action on any valid input. Examples of problems might be "given an integer ''n'', determine whether ''n'' is prime", or "given two numbers ''x'' and ''y'', calculate the product ''x''*''y''". As the inputs get bigger, the amount of computational resources needed to solve a problem will increase. Thus, the resources needed to solve a problem are described in terms of asymptotic analysis, by identifying the resources as a function of the length or size of the input. Resource usage is often partially quantified using Big O notation. Com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Scheduling Method
Linear scheduling method (LSM) is a graphical scheduling method focusing on continuous resource utilization in repetitive activities. Application LSM is used mainly in the construction industry to schedule resources in repetitive activities commonly found in highway, pipeline, high-rise building and rail construction projects. These projects are called repetitive or linear projects. The main advantages of LSM over critical path method (CPM) is its underlying idea of keeping resources continuously at work. In other words, it schedules activities in such a way that: # resource utilization is maximized; # interruption in on-going process is minimized, including hiring-and-firing; and # the effect of the learning curve phenomenon is maximized Alternative names According to, specific names for the linear scheduling method have been adopted, such as: *Location-based scheduling (the preferred term in the book) *Harmonograms *Line-of-balance *Flowline or flow line *Repetitive scheduli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scheduling Algorithms
In computing, scheduling is the action of assigning ''resources'' to perform ''tasks''. The ''resources'' may be central processing unit, processors, telecommunications link, network links or expansion cards. The ''tasks'' may be thread (computer science), threads, process (computing), processes or data flow (computer networking), flows. The scheduling activity is carried out by a process called scheduler. Schedulers are often designed so as to keep all computer resources busy (as in load balancing (computing), load balancing), allow multiple users to share system resources effectively, or to achieve a target quality of service, quality-of-service. Scheduling is fundamental to computation itself, and an intrinsic part of the execution model of a computer system; the concept of scheduling makes it possible to have computer multitasking with a single central processing unit (CPU). Goals A scheduler may aim at one or more goals, for example: * maximizing ''throughput'' (the total a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
