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1.
Software is a central component in the modern world and vastly affects the environment’s sustainability. The demand for energy and resource requirements is rising when producing hardware and software units. Literature study reveals that many studies focused on green hardware; however, limited efforts were made in the greenness of software products. Green software products are necessary to solve the issues and problems related to the long-term use of software, especially from a sustainability perspective. Without a proper mechanism for measuring the greenness of a particular software product executed in a specific environment, the mentioned benefits will not be attained. Currently, there are not enough works to address this problem, and the green status of software products is uncertain and unsure. This paper aims to identify the green measurements based on sustainable dimensions in a software product. The second objective is to reveal the relationships between the elements and measurements through empirical study. The study is conducted in two phases. The first phase is the theoretical phase, where the main components, measurements and practices that influence the sustainability of a software product are identified. The second phase is the empirical study that involved 103 respondents in Malaysia investigating current practices of green software in the industrial environment and further identifying the main sustainability dimensions and measurements and their impact on achieving green software products. This study has revealed seven green measurements of software product: Productivity, Usability, Cost Reduction, Employee Support, Energy Efficiency, Resource Efficiency and Tool Support. The relationships are statistically significant, with a significance level of less than 0.01 (p = 0.000). Thus, the hypothesised relationships were all accepted. The contributions of this study revolve around the research perspectives of the measurements to attain a green software product. 相似文献
2.
A steelmaking-continuous casting (SCC) scheduling problem is an example of complex hybrid flow shop scheduling problem (HFSSP) with a strong industrial background. This paper investigates the SCC scheduling problem that involves controllable processing times (CPT) with multiple objectives concerning the total waiting time, earliness/tardiness and adjusting cost. The SCC scheduling problem with CPT is seldom discussed in the existing literature. This study is motivated by the practical situation of a large integrated steel company in which the just-in-time (JIT) and cost-cutting production strategy have become a significant concern. To address this complex HFSSP, the scheduling problem is decomposed into two subproblems: a parallel machine scheduling problem (PMSP) in the last stage and an HFSSP in the upstream stages. First, a hybrid differential evolution (HDE) algorithm combined with a variable neighborhood decomposition search (VNDS) is proposed for the former subproblem. Second, an iterative backward list scheduling (IBLS) algorithm is presented to solve the latter subproblem. The effectiveness of this bi-layer optimization approach is verified by computational experiments on well-designed and real-world scheduling instances. This study provides a new perspective on modeling and solving practical SCC scheduling problems. 相似文献
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《工程(英文)》2019,5(4):637-645
The rapid development of information and communication technologies (ICTs) and cyber–physical systems (CPSs) has paved the way for the increasing popularity of smart products. Context-awareness is an important facet of product smartness. Unlike artifacts, various bio-systems are naturally characterized by their extraordinary context-awareness. Biologically inspired design (BID) is one of the most commonly employed design strategies. However, few studies have examined the BID of context-aware smart products to date. This paper presents a structured design framework to support the BID of context-aware smart products. The meaning of context-awareness is defined from the perspective of product design. The framework is developed based on the theoretical foundations of the situated function–behavior–structure ontology. A structured design process is prescribed to leverage various biological inspirations in order to support different conceptual design activities, such as problem formulation, structure reformulation, behavior reformulation, and function reformulation. Some existing design methods and emerging design tools are incorporated into the framework. A case study is presented to showcase how this framework can be followed to redesign a robot vacuum cleaner and make it more context-aware. 相似文献
5.
This paper proposes the application of Covariance Matrix Adaptation Evolution Strategy (CMA-ES) in fixed structure H∞ loop shaping controller design. Integral Time Absolute Error (ITAE) performance requirement is incorporated as a constraint with an objective of maximization of stability margin in the fixed structure H∞ loop shaping controller design problem. Pneumatic servo system, separating tower process and F18 fighter aircraft system are considered as test systems. The CMA-ES designed fixed structure H∞ loop-shaping controller is compared with the traditional H∞ loop shaping controller, non-smooth optimization and Heuristic Kalman Algorithm (HKA) based fixed structure H∞ loop shaping controllers in terms of stability margin. 20% perturbation in the nominal plant is used to validate the robustness of the CMA-ES designed H∞ loop shaping controller. The effect of Finite Word Length (FWL) is considered to show the implementation difficulties of controller in digital processors. Simulation results demonstrated that CMA-ES based fixed structure H∞ loop shaping controller is suitable for real time implementation with good robust stability and performance. 相似文献
6.
《Ceramics International》2020,46(4):4410-4415
Spinel Mg ferrites Mg1-xCdxCo0.05Fe1.95O4 (x=0.0, 0.2, 0.3 and 0.4) as potential agents for the miniaturization of high frequency antennas are presented. All the synthesized compositions were experimentally revealed to possess pure spinel phase. Dual-equivalent permeability and permittivity (μ'≈26, ε'≈25, x=0.3 and μ'≈29, ε'≈28, x=0.4) from 5 to 100 MHz can be achieved by introducing Cd2+ ions, yielding large miniaturization factors of up to 25 and 28. To figure out the effects of Cd2+ ions substitution on magnetic and dielectric properties, the change in microstructure is mainly investigated. Meanwhile, enhanced magnetic properties including upward saturation magnetization (Ms) (approximately 47.60 emu/g) and reduced coercivity (approximately 54.22 Oe) are obtained due to increased grain size and denser microstructure arrangements reflected from scanning electron microscopy images. With low magnitude order of magnetic and dielectric losses factors (tanδε reaches 10-4, tanδμ reaches 10-2), the composites can potentially exhibit high operating efficiencies at high frequencies. 相似文献
7.
Wang Lu-di Zhou Wei Xing Ying Liu Na Movahedipour Mahmood Zhou Xiao-guang 《浙江大学学报:C卷英文版》2019,20(3):405-413
Frontiers of Information Technology & Electronic Engineering - Reconstruction of a 12-lead electrocardiogram (ECG) from a serial 3-lead ECG has been researched in the past to satisfy the need... 相似文献
8.
《International Journal of Hydrogen Energy》2020,45(32):16169-16182
Copper indium disulfide (CuInS2) thin films as an absorption layer for solar cell and photocatalytic degradation of organic pollutants, were successfully electrodeposited on the FTO coated glass substrate using the simple and inexpensive electrodeposition method and a sulfurization process. The effects of the Cu/In molar ratio, annealing temperature and kind of Cu2+ precursor (Cu(salen) and Cu(acac)2 as novel Cu2+ precursors) on the structural and morphological properties of samples were examined. The XRD diffraction patterns and energy dispersive spectroscopy measurements exhibit that high-quality film with superior crystalline structure was formed in the presence of Cu(salen) as Cu2+ precursor. Also, we found that a suitable heat treatment temperature could suppress the CuS phases and form well-crystallized CIS. As we know, this is the first reported efficiency for any CuInS2 superstrate solar cell to date that fabricated using Cu(salen) as Cu2+ precursor. In addition, the photocatalytic degradation of organic dye in the presence of as-synthesized CuInS2 thin films was studied. The as-prepared semiconductor photocatalysts have a good reusability; it can be successfully reused for 5 times recycling photoactivity tests. 相似文献
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This article introduces the basic structure of a symmetric self-electrooptic effect device (S-SEED), and applies the Kirchoff' s current law and a purely equivalent capacitive model, to analyze S-SEED's switch characteristics. Linear approximation and N-segment approximation are utilized to obtain S-SEED's voltage-time (V-T) and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED's switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED's switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED's switch characteristics. 相似文献