Xiaohu Zheng, Dapeng Dong, Lixin Huang, Xibin Wang and Ming Chen
– The paper aims to investigate tool wear mechanism and tool geometry optimization of drilling PCB fixture hole.
Abstract
Purpose
The paper aims to investigate tool wear mechanism and tool geometry optimization of drilling PCB fixture hole.
Design/methodology/approach
An experimental study was carried out to investigate the chip formation and tool wear mechanism of drilling PCB fixture holes. Two types of drill with different types of chip-split groove were used in this study. The performances of these two types of drill bots were evaluated by tool wear and the shapes of chips.
Findings
The chips of drilling fixture holes contain aluminum chips from the cover board, copper chips from the copper foil, discontinuous glass fiber and resin from the CFRP. Feed rate and drilling speed have a great influence on the chip morphology. Abrasive wear of the drill lip is the main reason of the fixture drill bit in drilling PCB, and micro-chipping is observed on the tool nose and chisel edge. The influence of distance between the chip-split groove and drill point center on the axial force and torque is not obvious.
Research limitations/implications
In this paper, hole wall roughness and drilling temperature were not analyzed in the optimization of drilling parameters. The future research work should consider them.
Originality/value
This paper investigated the mechanism of burr formation and tool wear in drilling of PCB fixture holes. Tool geometry was optimized by adding chip-split grooves.
Details
Keywords
This paper aims to analyze their generation mechanism and factors influencing burr generation. The final goal is to use appropriate drill design and drilling process to control…
Abstract
Purpose
This paper aims to analyze their generation mechanism and factors influencing burr generation. The final goal is to use appropriate drill design and drilling process to control the generation of burrs.
Design/methodology/approach
The mechanism of burr generation was studied through finite element method (FEM) simulation and drilling experiments. High-speed photography technology and scanning electron microscope (SEM) were used in this study.
Findings
High-speed drilling burr is a printed circuit board (PCB) copper foil burr. Within a certain range, the feed speed and burr height is in positive correlation, and decrease in the feeding speed will favor the exit burr. Drill angle influences burr and chisel edge affect significantly, followed by the point angle, and helical angle has little effect. From the perspective of reducing the burr, a smaller chisel edge and smaller point angle should be chosen. Grinding chisel edge is another choice to decrease the burr but also ensures the blade strength.
Originality/value
This paper investigates the mechanism of burr generation of PCB fixture hole drilling. The process of burr generation was captured by high-speed camera. The controlling methods of burr generation were illustrated at the end.
Wenxiong Lin, Huagang Liu, Haizhou Huang, Jianhong Huang, Kaiming Ruan, Zixiong Lin, Hongchun Wu, Zhi Zhang, Jinming Chen, Jinhui Li, Yan Ge, Jie Zhong, Lixin Wu and Jie Liu
The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable…
Abstract
Purpose
The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable window, which is prepared by irradiating polyethylene terephthalate membranes with accelerated heavy ions.
Design/methodology/approach
Experimental approaches are carried out to characterize printing parameters of resins with different photo-initiator concentrations by a photo-polymerization matrix, to experimentally observe and theoretically fit the oxygen inhibition layer thickness during printing under conditions of pure oxygen and air, respectively, and to demonstrate the enhanced CLIP processes by using pure oxygen and air, respectively.
Findings
Owing to the high permeability of track-etched membrane, CLIP process is demonstrated with printing speed up to 800 mm/h in the condition of pure oxygen, which matches well with the theoretically predicted maximum printing speed at difference light expose. Making a trade-off between printing speed and surface quality, maximum printing speed of 470 mm/h is also obtained even using air. As the oxygen inhibition layer created by air is thinner than that by pure oxygen, maximum speed cannot be simply increased by intensifying the light exposure as the case with pure oxygen.
Originality/value
CLIP process is capable of building objects continuously instead of the traditional layer-by-layer manner, which enables tens of times improvement in printing speed. This work presents an enhanced CLIP process by first using a porous track-etched membrane to serve as the oxygen permeable window, in which a record printing speed up to 800 mm/h using pure oxygen is demonstrated. Owing to the high permeability of track-etched membrane, continuous process at a speed of 470 mm/h is also achieved even using air instead of pure oxygen, which is of significance for a compact robust high-speed 3D printer.
Details
Keywords
Zhixuan Lai, Gaoxiang Lou, Yuhan Guo, Xuechen Tu and Yushan Zhao
Considering two types of subsidies for producers (supplier and manufacturer) and one for consumers based on product greenness and sales quantity, this study aims to formulate…
Abstract
Purpose
Considering two types of subsidies for producers (supplier and manufacturer) and one for consumers based on product greenness and sales quantity, this study aims to formulate optimal supply chain green innovation and subsidy strategies, and to achieve this goal with the support of information systems.
Design/methodology/approach
This study introduces a composite green-product supply chain where suppliers focus on green innovation for component greenness and manufacturers focus on green innovation for manufacturing process greenness. Game theory modeling is applied to investigate the differences of product greenness, supply chain members’ profit and social welfare under different government subsidy strategies.
Findings
Increasing the unit greenness subsidy coefficient can boost product greenness and supply chain members’ profits, but does not always raise social welfare. When the government exclusively offers subsidies to producers, subsidies should be allocated to suppliers when there is a significant disparity in supply chain green innovation costs. Conversely, it is more beneficial to subsidize manufacturers. Consumer subsidies have the potential to enhance both environmental and economic performance in the supply chain compared with producer-exclusive subsidies, but may not always maximize social welfare when supply chain members have low unit costs associated with green innovation.
Originality/value
This study examines the optimal decisions for green supply chain innovation and government subsidy strategies. Supply chain members and the government can use the information system to collect and evaluate the cost of upstream and downstream green innovation, and then develop reasonable collaborative green innovation and subsidy strategies.
Details
Keywords
Tahira M. Probst, Lixin Jiang and Sergio Andrés López Bohle
The purpose of this paper is to test competing models of the relationship between job insecurity and two forms of impression management (self- and supervisor-focused) on job…
Abstract
Purpose
The purpose of this paper is to test competing models of the relationship between job insecurity and two forms of impression management (self- and supervisor-focused) on job performance. Specifically, does job insecurity lead to greater subsequent impression management; or, does preventative use of impression management subsequently lead to reductions in job insecurity? Additionally, how do these both relate to in-role performance?
Design/methodology/approach
Using two-wave survey data collected from 184 working adults in the USA and the two-step approach recommended by Cole and Maxwell (2003) and Taris and Kompier (2006), the authors tested cross-lagged relationship between job insecurity and both forms of impression management by comparing four different models: a stability model, a normal causation model (with cross-lagged paths from T1 job insecurity to T2 impression management), a reversed causation model (with cross-lagged paths from T1 impression management to T2 job insecurity) and a reciprocal causation model (with all cross-lagged paths described in the normal and reversed causation model).
Findings
Results were supportive of the reversed causation model which indicated that greater use of supervisor-focused impression management at Time 1 predicted lower levels of job insecurity at Time 2 (after controlling for prior levels of job insecurity); moreover, job insecurity at Time 1 was then significantly associated with more positive in-role behaviors at Time 2. Moreover, the test of the indirect effect between T1 impression management and T2 performance was significant.
Originality/value
These results suggest that impression management clearly plays an important role in understanding the relationship between job insecurity and job performance. However, employees appear to utilize impression management as a means of pre-emptively enhancing their job security, rather than as a tool to reactively cope with perceived job insecurity.
Details
Keywords
Nan Hu, Zhi Chen, Jibao Gu, Shenglan Huang and Hefu Liu
This paper aims to examine the effects of task and relationship conflicts on team creativity, and the moderating role of shared leadership in inter-organizational teams. An…
Abstract
Purpose
This paper aims to examine the effects of task and relationship conflicts on team creativity, and the moderating role of shared leadership in inter-organizational teams. An inter-organizational team normally comprises employees from collaborated organizations brought together to conduct an initiative, such as product development. Practitioners and researchers have witnessed the prevalence of conflict in inter-organizational teams. Despite significant scholarly investigation into the importance of conflict in creativity, a deep theoretical understanding of conflict framework remains elusive.
Design/methodology/approach
A questionnaire survey was conducted in China to collect data. Consequently, 54 teams, which comprised 54 team managers and 276 team members, were deemed useful for the study.
Findings
By testing our hypotheses on 54 inter-organizational teams, we found that relationship conflict has a negative relationship with team creativity, whereas task conflict has an inverted U-shaped (curvilinear) relationship with team creativity. Furthermore, when shared leadership is stronger, the negative relationship with team creativity is weaker for relationship conflict, whereas the inverted U-shaped relationship with team creativity is stronger for task conflict.
Research limitations/implications
The main limitation is cross-sectional, which cannot establish causality in relationships. Despite this potential weakness, the present research provides insights into conflict, leadership and inter-organizational collaboration literature.
Practical implications
The findings of this study offer some guidance on how managers can intervene in the conflict situations of inter-organizational teams.
Social implications
Managers are struggling to identify ways to effectively manage team conflict when a team of diverse individuals across organizational boundaries are brought together to solve a problem. The findings of this study offer some guidance on how managers can intervene in the conflict situations of inter-organizational teams.
Originality/value
This paper provides understandings about how relationship and task conflicts affect team creativity in inter-organizational teams.
Details
Keywords
Sanman Hu, Lixin Jiang, Qiong Zou and Mingqian Liu
Using conservation of resources and self-determination theories, this study explores the negative ties between proactive career behaviour and job insecurity, which are mediated by…
Abstract
Purpose
Using conservation of resources and self-determination theories, this study explores the negative ties between proactive career behaviour and job insecurity, which are mediated by work-related basic needs satisfaction, and how contract type affects these relationships.
Design/methodology/approach
Two waves of data were collected from 332 Chinese employees. The mediation and moderated mediation models were tested with MPLUS 8.30 and SPSS’s PROCESS macro.
Findings
Proactive career behaviour negatively affects (both quantitatively and qualitatively) job insecurity through work-related basic needs satisfaction. Contract type moderates the relationship between proactive career behaviour and work-related basic needs satisfaction as well as the indirect relationship between proactive career behaviour and quantitative (but not qualitative) job insecurity via work-related basic needs satisfaction. These findings suggest that temporary employees can obtain greater benefits by engaging in proactive career behaviour than can their permanent counterparts.
Originality/value
This study contributes to the limited research on job insecurity antecedents, mechanisms and key moderators.
Details
Keywords
Ji Li, Wanxing Jiang, Mengli Liu, Jun Huang and Xiaolong Tao
This study deals with the issue of how ethnic diversity on boards in a given firm may influence its performance in human resource management (HRM). Moreover, the study also tests…
Abstract
Purpose
This study deals with the issue of how ethnic diversity on boards in a given firm may influence its performance in human resource management (HRM). Moreover, the study also tests the interaction between ethnic diversity and gender diversity and examines their joint effect on HRM.
Design/methodology/approach
Based on prior research, we predict that, with increasing demographic diversity in organizations today, ethnic diversity on boards should have a positive effect on HRM. Moreover, gender diversity, as a most visible dimension of demographic diversity, should have both a direct positive effect and an indirect moderating effect on the relationship between ethnic diversity and HRM. Hierarchical regression analysis was conducted to test the hypotheses.
Findings
Our data analyses show empirical evidence supporting our predictions. First, our study shows that employer–employee relationship can be influenced by ethnic diversity on boards. Second, the foregoing analyses highlight the importance of considering the interaction between different dimensions of demographic diversity, such as that between ethnic and gender diversity. With a higher level of gender diversity on boards, the positive effect of ethnic diversity on HRM can become more salient.
Originality/value
This research tests the benefits of ethnic diversity on boards for improving firms’ performance in HRM, thus making a contribution by helping to understand the effects of ethnic diversity in a more comprehensive way. We also document the beneficial moderating effects of gender diversity on boards for the first time.
Details
Keywords
Yanhui Song, Lixin Lei, Lijuan Wu and Shiji Chen
This paper focuses on the differences in domain intellectual structure discovery between author bibliographic coupling analysis (ABCA) and author co-citation analysis (ACA…
Abstract
Purpose
This paper focuses on the differences in domain intellectual structure discovery between author bibliographic coupling analysis (ABCA) and author co-citation analysis (ACA) considering all authors. The purpose of this study is to examine whether and in what ways these two all-author network approaches yield different results.
Design/methodology/approach
The sample was collected from the database of Web of Science, including all articles published in Scientometrics and Journal of Informetrics from 2011 to 2020. First, 100 representative authors were selected from each set, and ABCA matrices and ACA matrices were constructed. Second, factor analysis was carried out on the matrices, to detect the intellectual structure of scientometrics and informetrics.
Findings
The intellectual structures identified by ABCA and ACA are similar overall, but the results differ somewhat when it comes to specific structures. The ABCA is more sensitive to some highly collaborative research teams and presents a clearer picture of current intellectual structures and trends while ACA seems to have some advantages in representing the more traditional and proven research topics in the field. The combined use of ABCA and ACA allows for a more comprehensive and specific intellectual structure of research fields.
Originality/value
This paper compares the performance of ABCA and ACA detecting the intellectual structure of the domain from the perspective of all authors, revealing the intellectual structure of scientometrics and informetrics comprehensively.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-12-2020-0540.