bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research progress of high-performance BEM and investigation on convergence of GMRES in local stress analysis of slender real thin-plate beams
Authors: Yao Zhenhan , Zheng Xiaoping , Yuan Han , Feng Jinlong 
Published: March 2019

Purpose
Based on the error analysis, the authors proposed a new kind of high accuracy boundary element method (BEM) (HABEM), and for the large-scale problems, the fast algorithm, such as adaptive cross approximation (ACA) with generalized minimal residual (GMRES) is introduced to develop the high performance BEM (HPBEM). It is found that for slender beams, the stress analysis using iterative solver GMRES will difficult to converge. For the analysis of slender beams and thin structures, to enhance the efficiency of GMRES solver becomes a key problem in the development of the HPBEM. The purpose of this paper is study on the preconditioning method to solve this convergence problem, and it is started from the 2D BE analysis of slender beams.

Design/methodology/approach
The conventional sparse approximate inverse (SAI) based on adjacent nodes is modified to that based on adjacent nodes along the boundary line. In addition, the authors proposed a dual node variable merging (DNVM) preprocessing for slender thin-plate beams. As benchmark problems, the pure bending of thin-plate beam and the local stress analysis (LSA) of real thin-plate cantilever beam are applied to verify the effect of these two preconditioning method.

Findings
For the LSA of real thin-plate cantilever beams, as GMRES (m) without preconditioning applied, it is difficult to converge provided the length to height ratio greater than 50. Even with the preconditioner SAI or DNVM, it is also difficult to obtain the converged results. For the slender real beams, the iteration of GMRES (m) with SAI or DNVM stopped at wrong deformation state, and the computation failed. By changing zero initial solution to the analytical displacement solution of conventional beam theory, GMRES (m) with SAI or DNVM will not be stopped at wrong deformation state, but the stress error is still difficult to converge. However, by GMRES (m) combined with both SAI and DNVM preconditioning, the computation efficiency enhanced significantly.

Originality/value
This paper presents two preconditioners: DNVM and a modified SAI based on adjacent nodes along the boundary line of slender thin-plate beam. In the LSA, by using GMRES (m) combined with both DNVM and SAI, the computation efficiency enhanced significantly. It provides a reference for the further development of the 3D HPBEM in the LSA of real beam, plate and shell structures.
Implementing the Multifactor Leadership Questionnaire (MLQ) in a challenging context
Authors: Van Jaarsveld Leentjie , Mentz P.J. (Kobus) , Ellis Suria 
Published: March 2019

Purpose
An emphasis on school performance is not just a national issue, but must be examined within the global context. Successful leadership is ensured by school leaders’ compliance to a set of basic practices within particular school contexts. The impact of leadership styles on performance, the work environment and job satisfaction is emphasized, while the appropriate leadership style could make teachers more effective in terms of job productivity. The adoption of different leadership styles by school leaders shows positive results with regard to school effectiveness. The purpose of this paper is to describe school leadership styles and the influence the styles have on school performance.

Design/methodology/approach
A quantitative approach with a post-positive paradigm was followed. A systematic random sample of 72 secondary schools in KwaZulu-Natal, South Africa, was selected. The Cronbach’s α coefficient, statistical significance (p-values) and effect size (d-values) were calculated, and a factor analysis was conducted.

Findings
The results show a difference between teachers and principals regarding the transformational leadership style. The principals in the high-performing schools were perceived as less passive-avoidant in practice than those in the low-performing schools. A principal manages and leads a school effectively by applying an appropriate leadership style.

Research limitations/implications
For future research, it will be advisable to make use of a mixed-method design. Although the Multifactor Leadership Questionnaire addressed numerous aspects of leadership and leadership styles, the “voice” of the respondents lacked. Furthermore, more leadership styles could be investigated in different contexts.

Practical implications
A chosen principal leadership style is not necessarily the best style for this purpose. School principals and teachers interpret leadership styles differently. Communication is therefore important.

Social implications
The principal leadership style is not always necessarily the teachers’ and learners’ choice. It is important that schools keep up with a constantly changing world.

Originality/value
If school principals and teachers agree upon a specific leadership style, there may be better collaboration which enhances better academic performance as well as effectiveness regarding schools.
Principals’ instructional leadership under statewide teacher evaluation reform
Authors: Lochmiller Chad R. , Mancinelli John L. 
Published: March 2019

Purpose
The purpose of this paper is to describe how elementary school principals adjust their leadership practice in response to Washington’s new teacher evaluation policy.

Design/methodology/approach
The authors conducted a modified content analysis of open-ended survey responses collected from elementary school principals in Washington State. In all, the survey included responses from 354 elementary school principals representing 25.0 percent of the state’s elementary school principal population. ATLAS.ti supported data analysis and assisted in the derivation of three key findings.

Findings
Elementary school principals changed their instructional leadership practice in response to the new teacher evaluation policy in three significant ways. First, principals adjusted their approach to classroom observation to complete more intentional, in-depth observational activities. Second, principals redistributed non-instructional responsibilities to clerical staff members to allow themselves and other administrators more time for classroom observation. Third, principals adopted a learning stance to the new policy and thus sought external support, especially coaching, to assist them with the implementation of new evaluation practices.

Research limitations/implications
The study faced three limitations. First, the sample of respondents included in this study cannot be generalized to the state as participants were not randomly selected. Second, the survey did not utilize a longitudinal design, and thus its findings only relate to the first year of the policy’s implementation. Third, the study does not include school-based evidence to triangulate principals’ survey responses.

Originality/value
The study contributes to the instructional leadership literature. Specifically, the study offers further insights into the adjustments principals make in their leadership to accommodate expectations found in new teacher evaluation policy.
Integrating neuro-fuzzy system and evolutionary optimization algorithms for short-term power generation forecasting
Authors: Jahangoshai Rezaee Mustafa , Dadkhah Mojtaba , Falahinia Masoud 
Published: March 2019

Purpose
This study aims to short-therm forecasting of power generation output for this purpose, an adaptive neuro-fuzzy inference system (ANFIS) is designed to forecast the output power of power plant based on climate factors considering wind speed and wind direction simultaneously.

Design/methodology/approach
Several methods and algorithms have been proposed for systems forecasting in various fields. One of the strongest methods for modeling complex systems is neuro-fuzzy that refers to combinations of artificial neural network and fuzzy logic. When the system becomes more complex, the conventional algorithms may fail for network training. In this paper, an integrated approach, including ANFIS and metaheuristic algorithms, is used for increasing forecast accuracy.

Findings
Power generation in power plants is dependent on various factors, especially climate factors. Operating power plant in Iran is very much influenced because of climate variation, including from tropical to subpolar, and severely varying temperature, humidity and air pressure for each region and each season. On the other hands, when wind speed and wind direction are used simultaneously, the training process does not converge, and the forecasting process is unreliable. The real case study is mentioned to show the ability of the proposed approach to remove the limitations.

Originality/value
First, ANFIS is applied for forecasting based on climate factors, including wind speed and wind direction, that have rarely been used simultaneously in previous studies. Second, the well-known and more widely used metaheuristic algorithms are applied to improve the learning process for forecasting output power and compare the results.
Learning to see distinctions through learning studies
Authors: Martensson Pernilla 
Published: March 2019

Purpose
The purpose of this paper is to identify changes in teacher’s pedagogical content knowledge (PCK) as a result of their participation in two learning studies in mathematics.

Design/methodology/approach
A group of four mathematics teachers and the researcher of this paper explored two objects of learning related to division with decimal numbers and the straight-line equation in a learning study (LS) project over the course of one year. The data used consist of eight video-recorded lessons, four written student tests, eight student interviews and 14 recorded team meetings. The analysis was based on the variation theory principle about learning (Marton, 2015) and on ontological assumptions within the phenomenographic approach (Marton, 1981).

Findings
It was found that teachers’ PCK was changed and refined through the LS process in terms of differences in ways of understanding and discussing critical aspects related to each object of learning. In the paper, the terms “presumed critical aspects” and “explored critical aspects” are used to illustrate this difference. Furthermore, the concepts are viewed in relation to three subdomains of PCK: knowledge of content and curriculum (KCC), knowledge of content and students (KCS) and knowledge of content and teaching (KCT).

Originality/value
Bringing out the difference between “presumed critical aspect” and “explored critical aspects” advances the view that critical aspects are dynamic and emergent in practice – in the interaction between teaching and student learning. The research exposes “explored critical aspects” as a specific form of PCK in which KCC, KCS and KCT are intertwined.
Enablers and inhibitors of cloud computing assimilation: an empirical study
Authors: Wang Nianxin , Liang Huigang , Ge Shilun , Xue Yajiong , Ma Jing 
Published: March 2019

PurposeThe purpose of this paper is to understand what inhibit or facilitate cloud computing (CC) assimilation.Design/methodology/approachThe authors investigate the effects of two enablers, top management support (TMS) and government support (GS), and two inhibitors, organization inertia (OI) and data security risk (DSR) on CC assimilation. The authors posit that enablers and inhibitors influence CC assimilation separately and interactively. The research model is empirically tested by using the field survey data from 376 Chinese firms.FindingsBoth TMS and GS positively and DSR negatively influence CC assimilation. OI negatively moderates the TMS–assimilation link, and DSR negatively moderates the GS–assimilation link.Research limitations/implicationsThe results indicate that enablers and inhibitors influence CC assimilation in both separate and joint manners, suggesting that CC assimilation is a much more complex process and demands new knowledge to be learned.Practical implicationsFor these firms with a high level of OI, only TMS is not enough, and top managers should find other effective way to successfully implement structural and behavioral change in the process of CC assimilation. For policy makers, they should actively play their supportive roles in CC assimilation.Originality/valueA new framework is developed to identify key drivers of CC assimilation along two bipolar dimensions including enabling vs inhibiting and internal vs external.
Modeling and prototyping of a soft closed-chain modular gripper
Authors: Anwar Muddasar , Khawli Toufik Al , Hussain Irfan , Gan Dongming , Renda Federico 
Published: March 2019

Purpose
This paper aims to present a soft closed-chain modular gripper for robotic pick-and-place applications. The proposed biomimetic gripper design is inspired by the Fin Ray effect, derived from fish fins physiology. It is composed of three axisymmetric fingers, actuated with a single actuator. Each finger has a modular under-actuated closed-chain structure. The finger structure is compliant in contact normal direction, with stiff crossbeams reorienting to help the finger structure conform around objects.

Design/methodology/approach
Starting with the design and development of the proposed gripper, a consequent mathematical representation consisting of closed-chain forward and inverse kinematics is detailed. The proposed mathematical framework is validated through the finite element modeling simulations. Additionally, a set of experiments was conducted to compare the simulated and prototype finger trajectories, as well as to assess qualitative grasping ability.

Findings
Key Findings are the presented mathematical model for closed-loop chain mechanisms, as well as design and optimization guidelines to develop controlled closed-chain grippers.

Research limitations/implications
The proposed methodology and mathematical model could be taken as a fundamental modular base block to explore similar distributed degrees of freedom (DOF) closed-chain manipulators and grippers. The enhanced kinematic model contributes to optimized dynamics and control of soft closed-chain grasping mechanisms.

Practical implications
The approach is aimed to improve the development of soft grippers that are required to grasp complex objects found in human–robot cooperation and collaborative robot (cobot) applications.

Originality/value
The proposed closed-chain mathematical framework is based on distributed DOFs instead of the conventional lumped joint approach. This is to better optimize and understand the kinematics of soft robotic mechanisms.
Implementation of a robot control architecture for additive manufacturing applications
Authors: Ribeiro Filipe Monteiro , Pires J. Norberto , Azar Amin S. 
Published: March 2019

Purpose
Additive manufacturing (AM) technologies have recently turned into a mainstream production method in many industries. The adoption of new manufacturing scenarios led to the necessity of cross-disciplinary developments by combining several fields such as materials, robotics and computer programming. This paper aims to describe an innovative solution for implementing robotic simulation for AM experiments using a robot cell, which is controlled through a system control application (SCA).

Design/methodology/approach
For this purpose, the emulation of the AM tasks was executed by creating a robot working station in RoboDK software, which is responsible for the automatic administration of additive tasks. This is done by interpreting gcode from the Slic3r software environment. Posteriorly, all the SCA and relevant graphical user interface (GUI) were developed in Python to control the AM tasks from the RoboDK software environment. As an extra feature, Slic3r was embedded in the SCA to enable the generation of gcode automatically, without using the original user interface of the software. To sum up, this paper adds a new insight in the field of AM as it demonstrates the possibility of simulating and controlling AM tasks into a robot station.

Findings
The purpose of this paper is to contribute to the AM field by introducing and implementing an SCA capable of executing/simulating robotic AM tasks. It also shows how an advanced user can integrate advanced simulation technologies with a real AM system, creating in this way a powerful system for R&D and operational manufacturing tasks. As demonstrated, the creation of the AM environment was only possible by using the RoboDk software that allows the creation of a robot working station and its main operations.

Originality/value
Although the AM simulation was satisfactory, it was necessary to develop an SCA capable of controlling the whole simulation through simple commands instructed by users. As described in this work, the development of SCA was entirely implemented in Python by using official libraries. The solution was presented in the form of an application capable of controlling the AM operation through a server/client socket connection. In summary, a system architecture that is capable of controlling an AM simulation was presented. Moreover, implementation of commands in a simple GUI was shown as a step forward in implementation of modern AM process controls.
Assessing the impact of students’ activities in e-courses on learning outcomes: a data mining approach
Authors: Keržič Damijana , Aristovnik Aleksander , Tomaževič Nina , Umek Lan 
Published: March 2019

Purpose
This paper aims to study the relationship between students’ activities in the e-classroom and grades for the final exam. The study was conducted at the Faculty of Administration, University of Ljubljana among first-year undergraduate students. In the e-classroom, students learn new content for individual self-study, and their knowledge is checked with quizzes.

Design/methodology/approach
In the empirical study, the relationship between performance in quizzes and at the final exam was studied from two perspectives. First, successful and unsuccessful students (in terms of quizzes) were compared. Second, the Orange data mining software was used for two predictive modelling tasks. The research question was based on a student’s quiz performances, is it possible to predict whether the student will pass an exam and will the student’s grade for the exam be good.

Findings
The empirical results indicate a very strong connection between a student’s performance in quizzes and their score for the final exam in the course. Significant differences in performance were found between students who had completed most quizzes and those who had not. Moreover, the results highlighted which quizzes, in other words topics, are most important for passing an exam or obtaining a better grade. Therefore, the quality of individual study in the e-classroom positively influences a student’s performance.

Originality/value
The paper is the first to assess the impact of students’ activities on learning outcomes in undergraduate public administration programmes by applying a data mining approach.
Overkill, we know it when we see it: examining definitions of excessive injury in homicide research
Authors: Trojan Carrie , Salfati C. Gabrielle , Schanz Kimberley 
Published: March 2019

PurposeThe purpose of this paper is to examine how the term “overkill” is used in the homicide literature to identify definitional issues that may interfere with reliable data coding across studies. This preliminary examination of the concept can guide future studies seeking to develop a standard definition.Design/methodology/approachTo identify issues inherent in the term “overkill,” three definitions – ranging from broad and unclear to more specific and objective – were extracted or adapted from the existing literature. Using closed, homicide case files, nine coders were tasked with coding for the presence of overkill according to one of the definitions across two rounds of coding. Definitional components that made the coding of overkill difficult were identified using a qualitative sorting task to separate items into themes that represented similar issues; basic inter-rater agreement patterns were examined using pairwise percent agreement.FindingsBased on coder feedback, two problems were identified: conceptual issues with the definitions and logistical issues with coding. However, feedback also suggested that increasing the objectivity of the overkill definition led coders to feel the intended meaning of the term was lost. Two out of three groups showed an increase in coder agreement between the two phases of data collection, illustrating how increased training is useful in certain situations.Originality/valueThis study is the first in-depth methodological and empirical examination of how the term “overkill” has been operationalized in the literature, raises key questions that may help with more clearly coding this variable, and outlines issues that may add difficulty to the development of a standard definition.
Governments, markets, and instruction: considerations for cross-national research
Authors: Peurach Donald J. , Cohen David K. , Spillane James P. 
Published: March 2019

Purpose
The purpose of this paper is to examine relationships among governmental organizations, non-governmental organizations and the organization and management of instruction in US public education, with the aim of raising issues for cross-national research among countries in which the involvement of non-governmental organizations is increasing.

Design/methodology/approach
The paper is structured in four parts: an historical analysis of the architecture and dynamics of US public education; an analysis of contemporary reform efforts seeking to improve quality and reduce inequities; an analysis of ways that legacy and reform dynamics manifest in two US public school districts; and a discussion of considerations for cross-national research.

Findings
In US public education, dependence on non-governmental organizations for instructional resources and services is anchored in deeply institutionalized social, political and economic values dating to the country’s founding and that continue to function as constraints on educational reform, such that new solutions always emerge in-and-from the same problematic conditions that they seek to redress. The consequence is that reform takes on an evolutionary (vs transformative) character.

Research limitations/implications
The US case provides a foundation for framing issues for cross-national research comparing among macro-level educational infrastructures, patterns of instructional organization and classroom instruction.

Originality/value
Such research would move beyond reductionist approaches to cross-national research toward new approaches that examine how histories, legacy architectures, contemporary reforms and patterns of instructional organization and management interact to shape students’ day-to-day lives in classrooms.