bluuebunny/crossref_metadata_2025_split huggingface dataset:
MTN-based recursive d-step-ahead predictive control of MIMO nonlinear systems with unknown input time-delay in industrial process
Authors: Yan Hong-Sen , Li Chen-Long 
Published: June 2022

Purpose
This paper aims to provide a precise tracking control scheme for multi-input multi-output “MIMO” nonlinear systems with unknown input time-delay in industrial process.

Design/methodology/approach
The predictive control scheme based on multi-dimensional Taylor network (MTN) model is proposed. First, for the unknown input time-delay, the cross-correlation function is used to identify the input time-delay through just the input and output data. And then, the scheme of predictive control is designed based on the MTN model. It goes as follows: a recursive d-step-ahead MTN predictive model is developed to compensate the influence of time-delay, and the extended Kalman filter (EKF) algorithm is applied for its learning; the multistep predictive objective function is designed, and the optimal controlled output is determined by iterative refinement; and the convergence of MTN predictive model and the stability of closed-loop system are proved.

Findings
Simulation results show that the proposed scheme is of desirable generality and capable of performing the tracking control for MIMO nonlinear systems with unknown input time-delay in industrial process effectively, such as the continuous stirred tank reactor (CSTR) process, which provides a considerably improved performance and effectiveness. The proposed scheme promises strong robustness, low complexity and easy implementation.

Research limitations/implications
For the limitations of proposed scheme, the time-invariant time-delay is only considered in time-delay identification and control schemes. And the CSTR process is only introduced to prove that the proposed scheme can adapt to practical industrial scenario.

Originality/value
The originality of the paper is that the proposed MTN control scheme has good tracking performance, which solves the influence of time-delay, coupling and nonlinearity and the real-time performance for MIMO nonlinear systems with unknown input time-delay.
Influence of slot profiles on the characteristics of jets
Authors: Krishnaraj Anusindhiya , Ganesan Vinayagamurthy 
Published: June 2022

Purpose
The purpose of this research is to study and investigate the flow control of 0.8 Mach jet using three tab configurations. The tabs with the slots will eventually lead to generation of vortices and thus enhances the mixing characteristics.

Design/methodology/approach
The jet flow control is achieved by the usage of three tabs, namely, Tab A, Tab B and Tab C that are placed at the exit plane of the convergent nozzle at 180 degrees apart. Three tabs with different slot profile are designed with the same constant blockage ratio of 7.3%. The tabs produce vortices of varying sizes that directly influence and modify the jet structure, thereby enhancing the efficiency in mass entrainment and mixing. The tabs are studied numerically first and then are compared with the results of the experiments.

Findings
The results are compared with that of the results of the uncontrolled jet. For Mach 0.8 jet, Tab C is found to reduce the core length and gives reduction of 90.23%, in comparison to Tab A and Tab B, which provides 84.1% and 87.79%, respectively. The results of numerical are then compared with the centerline results obtained via experiments. With the engagement of Tabs A, B and C, the jet structure is seen to have been modified at Mach 0.8 with Tab C performing better.

Practical implications
The tabs are a passive control device that can be practically enabled in the aircraft nozzles to control the flow and even suppress the noise emanated by the jet. Tabs can be effectively used for better thrust vector control and assist in jet noise suppression. Thus, this study on tabs and its uses are important and essential in aerospace technology.

Originality/value
This particular study on mechanical slotted tabs is innovatively carried out by designing the tabs in such a way that one such has not been designed before. The slots run through the adjacent sides of the tabs which is a novelty in itself, whereas perforations made only through the opposite sides of the tabs are studied by various researchers till now. The slots in the adjacent faces modify the flow physics in such a way that it enhances mixing by the creation of turbulence because of the interaction between the main stream and the secondary jet exactly at the core. So far, such slots and profiles are not investigated. By the usage of such tabs, the flow to mix faster is much closer to the core of the jet by creating mixed size vortices and thus has higher efficiency.
Economic competitiveness and taxes
Authors: Hodges Hart , Anderson Brady Flynn 
Published: June 2022

Purpose
The purpose of this paper is to determine whether the way competitiveness is measured matters, as well as to analyze the relationship between tax burden and economic competitiveness using a variety of model specifications.

Design/methodology/approach
This paper uses statistical models aimed at finding the relationship between taxes and different measures of economic competitiveness, such as gross domestic product per capita, employment and a third-party competitiveness index. Other variables are also considered, and statistical procedures such as lag specifications and “white period” errors are used to address problems of endogeneity and serial correlation.

Findings
The models find no robust relationship between taxes and competitiveness. Certain models find correlations between the tax burden of specific income groups with economic competitiveness, but these vary in direction and are difficult to interpret. This follows past research, which shows different results depending on the period analyzed, measure of competitiveness and other variables used.

Originality/value
This paper looks at many of the different measures of competitiveness, control variables and periods that are used in the previous literature and shows how any changes to these model specifications cause inconsistent results. This paper highlights that, because results can vary greatly depending on the model, researchers and policymakers must be careful when drawing any conclusions from relationships between taxes and economic competitiveness.
Frictional moment and wear modelling for incomplete spherical pistons in a spherical pump
Authors: Guan Dong , Chen Zhengrong 
Published: June 2022

Purpose
Because of the specific structure and working mechanism, piston speed is only half of its shaft, which causes severally friction between piston and cylinder. Therefore, the main purpose of this paper is to investigate the friction and wear characteristics of the incomplete spherical piston in spherical pump comprehensively. Finally, to search the low-friction and wear-resistance structural pattern of the piston, and enhance the durability of spherical pump.

Design/methodology/approach
The non-linear frictional moment model for incomplete spherical piston in spherical pump was derivated quantificationally. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The theoretical wear model of piston–cylinder pair is proposed as well.

Findings
To reduce the frictional moment between incomplete piston and cylinder, the optimised diameter ratio between piston pin and piston should be 0.12 based on the parameter sensitivity analyses. The maximum frictional moment is approximately 2.5 times of the minimum. The total efficiency should be considered synthetically based on the thickness of specific working medium.

Originality/value
The proposed non-linear frictional moment model offers the quantitative estimations. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The wear behaviours of the piston and cylinder were analysed to investigate the wear characteristics of the piston.
Multi-objective optimal trajectory planning of customized industrial robot based on reliable dynamic identification for improving control accuracy
Authors: Hou Renluan , Niu Jianwei , Guo Yuliang , Ren Tao , Han Bing , Yu Xiaolong , Ma Qun , Wang Jin , Qi Renjie 
Published: June 2022

Purpose
The purpose of this paper is to enhance control accuracy, energy efficiency and productivity of customized industrial robots by the proposed multi-objective trajectory optimization approach. To obtain accurate dynamic matching torques of the robot joints with optimal motion, an improved dynamic model built by a novel parameter identification method has been proposed.

Design/methodology/approach
This paper proposes a novel multi-objective optimal approach to minimize the time and energy consumption of robot trajectory. First, the authors develop a reliable dynamic parameters identification method to obtain joint torques for formulating the normalized energy optimization function and dynamic constraints. Then, optimal trajectory variables are solved by converting the objective function into relaxation constraints based on second-order cone programming and Runge–Kutta discrete method to reduce the solving complexity.

Findings
Extensive experiments via simulation and in real customized robots are conducted. The results of this paper illustrate that the accuracy of joint torque predicted by the proposed model increases by 28.79% to 79.05% over the simplified models used in existing optimization studies. Meanwhile, under the same solving efficiency, the proposed optimization trajectory consumes a shorter time and less energy compared with the existing optimization ones and the polynomial trajectory.

Originality/value
A novel time-energy consumption optimal trajectory planning method based on dynamic identification is proposed. Most existing optimization methods neglect the effect of dynamic model reliability on energy efficiency optimization. A novel parameter identification approach and a complete dynamic torque model are proposed. Experimental results of dynamic matching torques verify that the control accuracy of optimal robot motion can be significantly improved by the proposed model.
The prehistoric entrepreneur: rethinking the definition
Authors: Lidow Derek Balfour 
Published: June 2022

Purpose
This paper aims to derive a time and place invariant definition of entrepreneurship necessary for the identification of prehistoric entrepreneurial behavior.

Design/methodology/approach
The definition was derived by correlating a diverse set of archeological artifacts that could correspond to entrepreneurial activity with established anthropological and historical evidence of ancient entrepreneurial activity. The definition was formulated as a compact operational definition to ensure it could produce yes or no answers to whether specific archeological, anthropological or historical records could be associated with entrepreneurial activity.

Findings
This effort produced a unique time and place independent definition of entrepreneur that enables the identification of prehistoric entrepreneurial activity and heretofore unrealized structure of entrepreneurial activity. Specifically, entrepreneurship as defined herein predates social hierarchy, political economy, markets and pricing mechanisms. Modern definitions often inconsistently limit the scope of entrepreneurial behavior.

Research limitations/implications
This analysis was performed based upon specific, not exhaustive, sets of archeological, anthropological and historical records. Unexamined records or new discoveries could yield examples of entrepreneurial activity that transcend this definition.

Practical implications
This definition challenges how we think about, measure and model entrepreneurial impact today and opens new avenues of inquiry to understanding the social and economic impacts of entrepreneurial behavior.

Originality/value
A time and place invariant operational definition of entrepreneurship that could precisely identify entrepreneurial activity in the archeological record has not existed before. The definition enables the author to identify entrepreneurial activity among hunter-gatherers and in other locations not previously identified.
The disposition effect and its manifestations in South African investor teams
Authors: Shandu Philani , Alagidede Imhotep Paul 
Published: June 2022

PurposeThe study endeavours to determine (1) whether the disposition effect exists among South African investor teams, (2) whether it is causally intensified by a set of psychosocial factors and (3) whether the disposition effect causally reduces investor welfare.Design/methodology/approachFollowing a natural field experimentation design involving a sample of investor teams participating in the 2019 run of the JSE University Investment Challenge, the authors use regression adjustments as well as bootstrap tests to investigate the casual implications of a set of psychosocial factors on the intensity of the disposition effect, as well on the attenuation of market-adjusted ex post returns (i.e. investor welfare).FindingsSouth African investor teams are susceptible to the disposition effect, and their susceptibility to the bias is associated with attenuated investor welfare. Furthermore, low female representation in an investor team causally intensifies the disposition effect, subsequently leading to a causal reduction in investor welfare.Originality/valueUsing evidence from real-world observation, the authors contribute to the literature on team gender diversity and investment decision-making, and – using Hofstede's (2001) cultural dimensions – the authors offer a comprehensive account for how differences in culture may lead to differences in gender-related disposition effects across different nationalities. The authors also introduce to the literature experimental evidence from the field that clearly demonstrates that – among South African investor teams – a causal relationship exists (1) between female representation and the disposition effect, and (2) between the disposition effect and investor welfare.
Is the future of AI sustainable? A case study of the European Union
Authors: Perucica Natasa , Andjelkovic Katarina 
Published: June 2022

Purpose
The purpose of this paper is to raise awareness on the need for a more comprehensive approach on the interdependence between artificial intelligence (AI) and environmental sustainability. It provides an overview of existing sustainable AI policy initiatives at the national and regional level. More precisely, it discusses whether existing European Union (EU) environmental policies are suitable for the AI era or whether new regulations are needed in this field. Finally, this paper assesses cross-fertilisation opportunities between the EU and non-EU countries.

Design/methodology/approach
This study is based on a qualitative analysis of sustainable applications of AI and the sustainability of AI. Emphasis is laid on the latter, and a “sustainable by design” approach is proposed, which in essence is a prerequisite for transparent, responsible and human-centred AI systems. The analysis primarily focuses on environmental sustainability.

Findings
The majority of studies focus on how to use AI to protect the environment with very little attention paid to sustainable design of AI. On the other hand, the EU’s comprehensive approach towards sustainable AI is closest to promoting “sustainable by design” AI. Several ways have been identified in which the EU’s actions can be translated beyond its borders.

Research limitations/implications
One of the largest limitations of this study is its moderate scope. This paper is confined to the EU and as such provides a limited assessment of global policies and measures on the interplay between sustainability and AI. Consequently, the paper did not provide an in-depth analysis of environmental policies worldwide that could help provide a better picture of possible cooperation areas or common grounds. Another limitation of this study is that it primarily focuses on environmental aspects and as such accords little attention to the economic and social pillars of sustainability.

Social implications
With less than 10 years to go before reaching the sustainable development goal deadline, this study can help stakeholders better understand what is being done worldwide in terms of sustainable AI. Moreover, given that the technology is still in its early phase, this study can inspire a “sustainable by design” approach to the development of AI technologies.

Originality/value
All national AI strategies published by 1 June 2021 were analysed to identify whether and to what extent they prioritise the interplay between environment and AI. Furthermore, the authors also looked at the EU policy and how it aims to address AI from a sustainable perspective.
Considering inner and outer bark as distinctive tissues helps to disentangle the effects of bark traits on decomposition
Authors: Lin Li , Song Yao‐Bin , Li Yikang , Goudzwaard Leo , van Logtestijn Richard S. P. , Chang Chenhui , Broekman Rob , van Hal Jurgen , Zuo Juan , Sterck Frank J. , Poorter Lourens , Sass‐Klaassen Ute , Hefting Mariet M. , Cornelissen Johannes H. C. 
Published: June 2022

Abstract

Revealing the ecological consequences of bark multifunctionality and its underlying traits has become a relatively new but essential focus in plant ecology. Although the enormous differences between the most crucial bark layers, that is, inner and outer bark, in structure and functions have been widely recognized, the overall bark has been regarded as a homogenous tissue in most bark‐related studies. This has led to poor knowledge on the functional independence, specialized contributions and possible linkages of inner and outer bark traits across tree species when further evaluating the crucial ecosystem functions that bark provides, especially in driving variation in bark decomposition.

To fill this research gap, we used a ‘common garden experiment’ on deadwood of six gymnosperms in a temperate forest in the Netherlands over 4 years of decomposition. We evaluated the differences and associations between the inner and outer bark in initial functional traits, decomposition rates and afterlife effects of traits in driving in situ bark decomposition across tree species at the earlier decomposition stage.

We report four main findings: (1) inner and outer bark traits varied significantly and were not coordinated across tree species; (2) correspondingly, the decomposition of the inner and outer bark were asynchronous and not coordinated across species and inner bark generally decomposed faster than outer bark; (3) the strong predictive traits driving bark decomposability were bark layer‐specific, with several inner bark traits controlling inner bark decomposition rates but outer bark decomposability being poorly predicted by outer bark traits and (4) besides being controlled by inner bark traits, inner bark decomposition was also indirectly regulated by several functional traits and the structure‐related trait spectrum of outer bark.

Synthesis. This is the first study that has linked functional traits, decomposability and afterlife effects of the inner and outer bark within the bark quantitatively. We highlight the significance of separating functional traits and ecological consequences of the inner and outer bark in research in bark ecology and deadwood dynamics, rather than erroneously considering bark as a homogeneous tissue. Such research will help to better evaluate the function‐oriented contribution of bark to the turnover of forest carbon and biogeochemical cycles from local to global scale.
Understanding rural and urban perceptions of seagrass ecosystem services for their blue carbon conservation strategies in the Philippines
Authors: Quevedo Jay Mar D. , Uchiyama Yuta , Kohsaka Ryo 
Published: June 2022

AbstractSeagrass meadows provide diverse ecosystem services that directly or indirectly benefit the coastal communities. Despite this, they are among the most threatened coastal ecosystems. Though coastal and marine conservation actions have progressed over the years, seagrasses received less attention compared with other more charismatic ecosystems such as coral reefs and mangroves. Among the influencing factors, the lack of societal recognition of what seagrasses are and their importance underlies the global crisis of seagrass conservation. Thus, in this study, we gathered rural and urban perceptions of seagrass ecosystem services, their threats, and management‐related activities at the unit of barangay or village in the Philippines. Overall, rural respondents displayed higher awareness of seagrass ecosystem services than urban respondents. Socio‐economic status and personal connection or direct experience to these services influenced their perceptions. Local‐level threats were also perceived and recognizing these at the early onset can avoid severe habitat degradation. Though the role of seagrass blue carbon in climate change mitigation was barely discussed in local contexts, the impact of climate change‐induced stressors on seagrass was perceived by the respondents. Thus, local stakeholders, practitioners, and policymakers have the opportunity to design future seagrass‐focused management plans and programs in the era of climate change.
Using a Multi‐Institutional Ensemble of Watershed Models to Assess Agricultural Conservation Effectiveness in a Future Climate
Authors: Kujawa Haley , Kalcic Margaret , Martin Jay , Apostel Anna , Kast Jeffrey , Murumkar Asmita , Evenson Grey , Aloysius Noel , Becker Richard , Boles Chelsie , Confesor Remegio , Dagnew Awoke , Guo Tian , Muenich Rebecca Logsdon , Redder Todd , Wang Yu‐Chen , Scavia Donald 
Published: June 2022

ABSTRACTThis study investigates the combined impacts of climate change and agricultural conservation on the magnitude and uncertainty of nutrient loadings in the Maumee River Watershed, the second‐largest watershed of the Laurentian Great Lakes. Two scenarios — baseline agricultural management and increased agricultural conservation — were assessed using an ensemble of five Soil and Water Assessment Tools driven by six climate models. The increased conservation scenario included raising conservation adoption rates from a baseline of existing conservation practices to feasible rates in the near future based on farmer surveys. This increased adoption of winter cover crops on 6%–10% to 60% of cultivated cropland; subsurface placement of phosphorus fertilizers on 35%–60% to 68% of cultivated cropland; and buffer strips intercepting runoff from 29%–34% to 50% of cultivated cropland. Increased conservation resulted in statistically significant (p ≤ 0.05) reductions in annual loads of total phosphorus (41%), dissolved reactive phosphorus (18%), and total nitrogen (14%) under the highest emission climate scenario (RCP 8.5). While nutrient loads decreased with increased conservation relative to baseline management for all watershed models, different conclusions on the true effectiveness of conservation under climate change may be drawn if only one watershed model was used.