We present a C++ library for transparent memory and compute abstraction across CPU and GPU architectures. Our library combines generic data structures like vectors, multi-dimensional arrays, maps, graphs, and sparse g...
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We present a C++ library for transparent memory and compute abstraction across CPU and GPU architectures. Our library combines generic data structures like vectors, multi-dimensional arrays, maps, graphs, and sparse grids with basic generic algorithms like arbitrary-dimensional convolutions, copying, merging, sorting, prefix sum, reductions, neighbor search, and filtering. The memory layout of the data structures is adapted at compile time using C++ tuples with optional memory double-mapping between host and device and the capability of using memory managed by external libraries with no data copying. We combine this transparent memory layout with generic thread-parallel algorithms under two alternative common interfaces: a CUDA-like kernel interface and a lambda-function interface. We quantify the memory and compute performance and portability of our implementation using micro-benchmarks, showing that the abstractions introduce negligible performance overhead, and we compare performance against the current state of the art in a real-world scientific application from computational fluid mechanics.
Interest is growing in simple, fast and inexpensive systems to analyze urban wastewater quality in real time. In this re-search project, a methodology is presented for the characterization of COD, BOD5, TSS, TN, and T...
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Interest is growing in simple, fast and inexpensive systems to analyze urban wastewater quality in real time. In this re-search project, a methodology is presented for the characterization of COD, BOD5, TSS, TN, and TP of wastewater sam-ples, without the need to alter the samples or use chemical reagents, from a few wavelengths, belonging to the different color groups that compose the visible spectrum in isolation: (380-700 nm): violet (380-427 nm), blue (427-476 nm), cyan (476-497 nm), green (497-570 nm), yellow (570-581 nm), orange (581-618 nm), and red (618-700 nm). In this study, about 650 raw and treated urban wastewater samples from over 43 WWTPs and a total of 36 estimation models based on genetic algorithms have been calculated. Seven models were calculated for each pollutant parameter;one model for each color group of the visible spectrum, except for TN, which includes an additional model combining the wavelengths of the violet and red region of the spectrum. All the calculated models showed high accuracy, with an R2 between 80 and 85 % for COD, BOD5 and TSS, and 66-74 % for TN and TP. The tests carried out have shown the accuracy of the models of the different color groups to be very close to each other. However, it is noted that the models making use of the wavelengths between 497 and 570 nm (green) were the ones that showed the best perfor-mance in all the parameters under study. This research work lays the foundations for the development of cheaper, faster, and simpler wastewater monitoring and characterization equipment.
The goal of this study is to investigate the effect of actuator position on the theoretical energy consumption of an electrically powered bipedal robot. Specifically, the study focuses on the legs of the afore-mention...
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The goal of this study is to investigate the effect of actuator position on the theoretical energy consumption of an electrically powered bipedal robot. Specifically, the study focuses on the legs of the afore-mentioned robot because their function is limited, as they are primarily used for either locomotion or standing, and thus, this is suitable for optimization. Furthermore, the hip and knee joints constitute the most powerful joints, and thus, these are studied first. A mathematical formulation is adopted to represent the relationship between the actuators and the robots joints. A genetic optimization is used to minimize the energy loss due to motor winding resistance and no-load torque by altering the position of the actuator with respect to the joints. The results indicate that the energy lost during typical motions can be reduced by up to 30% by using bi-articular actuation. Additionally, most benefits can be realized by adding only a bi-articular actuator between the hip roll and knee pitch axes.
There are some limitations that using generic algorithms to dispose multimodal function,so that this paper brings forward an improved hybrid genetic *** block crossover,hierarchical mutation and multimodal function se...
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There are some limitations that using generic algorithms to dispose multimodal function,so that this paper brings forward an improved hybrid genetic *** block crossover,hierarchical mutation and multimodal function searching are adopted,which based on the analysis of variance *** improvement can not only expand the range of searching the individual with high fitness and accelerate the convergence rate,but also avoid the local *** to analysis of variance ratio,optimal value and the tolerance of every parameter in problem are solved at the same time,which is very practical for actual *** based on the analysis of variance ratio can not only speed up the calculation but also avoid the slow convergence at the late stage of the traditional *** hybrid coding of decimal and floating can fit in with the needs of the continuous variables and the dispersed variables in the actual engineering *** above improved methods have passed the test of GA test functions successfully,which has better search precision,convergent speed and capacity of global *** result shows that this hybrid generic algorithm is high efficiency,less genetic generation,and high accuracy for multimodal function.
Business performance measurement approaches have evolved over the long run. Some of them formed more than fifty years ago, others have been a matter of the last decade. As a result of the theoretical concepts dealing ...
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Business performance measurement approaches have evolved over the long run. Some of them formed more than fifty years ago, others have been a matter of the last decade. As a result of the theoretical concepts dealing with corporate governance and financial analysis, as well as the pragmatic practices used in corporate practice, we consider a wide range of approaches to expressing the company's performance from the perspective of the owners that formed during the development. The increasing pressure on business competitiveness in the globalization environment leads economists to make more realistically the economic benefits and success of business activities. Modern approaches to assessing business efficiency arise from criticism of traditional approach and their conceptual barrier arises between market valuation and efficiency, measured by accounting methods and procedures. Modern indicators should allow the use of as much information as possible from accounting, risk-taking and take into account the extent of tied capital, enable clear and transparent identification of ties at all levels of corporate governance, and enable performance and valuation of the firm. This is why we are focusing on a modern approach by using data envelopment analysis and measuring performance using artificial neural networks.
Quicksort is the preferred in-place sorting algorithm in many contexts, since its average computing time on uniformly distributed inputs is Θ( N log N ), and it is in fact faster than most other sorting algorithms on...
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