The PID controller is the by far most frequently employed type of controller. As you read, billions of digitally implemented PID controllers are running, shaping the dynamic behavior of anything from the fan speed in ...
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The PID controller is the by far most frequently employed type of controller. As you read, billions of digitally implemented PID controllers are running, shaping the dynamic behavior of anything from the fan speed in your laptop to safety-critical components in nuclear power plants. Given the abundance of commissioned PID controllers, it is surprisingly hard to find a single source that provides a well-documented, and motivated reference implementation of the PID controller in text-based code. This work provides one. We use the incremental (velocity) form, motivated by its intrinsic integrator anti-windup and bumpless transfer behavior. In addition, we discuss our implementation in terms of measurement filtering, setpoint handling, and runtime environment, among other implementation aspects. Our reference implementation is a living "document", and a link to a GitHub repository hosting the latest version is provided.
Colour is the first quality attribute of food that consumers examine and it is an important component of food quality that influences market acceptance. Classification of fruits by visual inspection is an arduous, tim...
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Colour is the first quality attribute of food that consumers examine and it is an important component of food quality that influences market acceptance. Classification of fruits by visual inspection is an arduous, time-consuming process and prone to human error. The machine vision system is a distributed control system that integrates several machine vision modules with a control module and a user interface unit. This research proposes a method for recognising and sorting tomato fruits into a preferred location continuously. Before designing colour sorter the physical properties of fruits were studied. The major and minor diameter of the tomatoes ranges from 45-60mm and 35-50mm, respectively. The mean geometric diameter, sphericity and surface area were 48.64mm,0.94 and 6477.14mm2 respectively. The average length, width, thickness, bulk density and true density were 54.63mm, 48.44mm, 51.42mm, 0.6874g/cm3, 0.9852g/cm3, respectively. The colour sorter was researched, designed and created with Raspberry Pi, USB camera, servo motor and different digital as well as mechanical components. The model used for Raspberry Pi is Raspberry Pi 3 Model B+, USB camera with a video resolution of 640 x 480, 4.2-6V servo motor. Image evaluation is completed on each captured picture and Raspberry Pi will do the selection of which fruit can be sorted. Specific programming code in Python is written for this system. The developed colour sorter captures images and diverts fruits into the respective channel at the rate of 1800 fruits/h (*** fruit per 2 seconds).
The PID controller is the by far most frequently employed type of controller. As you read, billions of digitally implemented PID controllers are running, shaping the dynamic behavior of anything from the fan speed in ...
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The PID controller is the by far most frequently employed type of controller. As you read, billions of digitally implemented PID controllers are running, shaping the dynamic behavior of anything from the fan speed in your laptop to safety-critical components in nuclear power plants. Given the abundance of commissioned PID controllers, it is surprisingly hard to find a single source that provides a well-documented, and motivated reference implementation of the PID controller in text-based code. This work provides one. We use the incremental (velocity) form, motivated by its intrinsic integrator anti-windup and bumpless transfer behavior. In addition, we discuss our implementation in terms of measurement filtering, setpoint handling, and runtime environment, among other implementation aspects. Our reference implementation is a living “document”, and a link to a GitHub repository hosting the latest version is provided.
Software-controlled caches, often called scratch-pad memories (SPM), are being increasingly used due to their efficiency. And to exploit all the advantages of SPMs an efficient allocation must be done in software. In ...
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ISBN:
(纸本)9781424468508
Software-controlled caches, often called scratch-pad memories (SPM), are being increasingly used due to their efficiency. And to exploit all the advantages of SPMs an efficient allocation must be done in software. In this work we propose a runtime operating system management approach for SPMs that do not require compiler support, application profiling or hardware support. The OS will use annotations, inserted into the code by the programmer, as hints to choose the most appropriate level in the memory hierarchy to allocate the data. The results showed that we were able to implement a run-time SPM allocation technique without adding any significant overhead to the system when compared with manual allocation.
Two book reviews of The Best Software Writing I by Joel Spolsky and Return on Software: Maximizing the Return on Your Software Investment by Steve Tockey.
Two book reviews of The Best Software Writing I by Joel Spolsky and Return on Software: Maximizing the Return on Your Software Investment by Steve Tockey.
The problems inherent in the task of developing and maintaining information systems have received wide coverage. The need for more comprehensive approaches to system development has never been so great. The paper is c...
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The problems inherent in the task of developing and maintaining information systems have received wide coverage. The need for more comprehensive approaches to system development has never been so great. The paper is concerned with the problems of developing and enhancing large, data-intensive, transaction-oriented systems (Business Information Systems). The essential problem with these systems is their inflexibility to change, compounded by the fact that most contemporary software processes fail to adequately address the specific problem of system evolution. The paper argues that the development of information systems requires the adoption of a new paradigm which recognises the explicit separation of organisational policy from programming code. This paradigm is regarded as an extension of contemporary practices which treat data and interfaces as being separate from application programs. A rule-based development environment, known as RUBRIC, is described, which serves as the means of achieving the objectives of this new paradigm.
Evolutionary model sequences for (X, Z)=(0.7,4×10−3) are constructed by using the same input physics and programming code as those of Saioet al. (1977). From these results the ages of globular clusters are estima...
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Evolutionary model sequences for (X, Z)=(0.7,4×10−3) are constructed by using the same input physics and programming code as those of Saioet al. (1977). From these results the ages of globular clusters are estimated under the assumption of constant helium abundance (Y=0.3). The results suggest that there is a correlation between age and metal abundance for the globular clusters and that metal enrichment in the Galaxy slowly proceeded in several billion years from the value of the extreme Population II stars to that of the Population I stars. Comparison with some models of chemical evolution of galaxies is briefly made.
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