A Vibration-Assisted Separation Method for Constrained-Surface-Based Stereolithography

2020 ◽  
Vol 143 (5) ◽  
Author(s):  
Yang Xu ◽  
Yizhen Zhu ◽  
Yifeng Sun ◽  
Jie Jin ◽  
Yong Chen
Keyword(s):  
Underlying Mechanism ◽  
Separation Method ◽  
Prototype System ◽  
Separation Performance ◽  
Separation Mechanism ◽  
Bottom Up ◽  
Trade Offs ◽  
Separation Force ◽  
The Relationship ◽  
Force Data

Abstract For the bottom-up based stereolithography (SL) process, a separation process is required to detach the newly cured layer from the constrained surface in the fabrication process. Excessive separation force will cause damage to the built layers and the constrained surface. Different surface coatings, platform motions including tilting and sliding, and the utilization of oxygen-permeable films have been developed to address the separation-related problems. Among these approaches, the vibration-assisted (VA) separation method to reduce the separation force has limited study. The underlying mechanism of the VA separation-based method remains unexplored, and the best way to use VA separation in the bottom-up based SL process is still unclear. In this paper, a new VA separation design for the SL process is presented. A prototype system was built to study the VA separation mechanism. Experiments on the separation performance under different parameters, including vibration frequency, pre-stress level, and exposure area, were conducted. Based on the collected separation force data, an analytical model based on the mechanics of fatigue fracture was built. The separation behaviors related to different shape size and topology were also studied and compared. The results showed that the separation force in SL was significantly reduced using the VA separation-based method. Furthermore, the relationship between the separation force and the separation time conforms to the stress-based fatigue model. This study also provides insights on how to choose process parameters by considering the trade-offs between separation force and building efficiency.

Consumers Complain More Fiercely Through Small-Screen Devices: The Role of Spatial Crowding Perception

2020 ◽  
Vol 23 (3) ◽  
pp. 353-367
Author(s):  
Yuanyuan Zhou ◽  
Bin Tian ◽  
Tingting Mo ◽  
Zhuoying Fei
Keyword(s):  
Secondary Data ◽  
Underlying Mechanism ◽  
Screen Size ◽  
Design Elements ◽  
Perception Theory ◽  
Fourth Experiment ◽  
Complaint Behavior ◽  
The Relationship ◽  
Small Screen

Previous research has mainly focused on the determinants of consumers’ complaint channel choices. Little attention has been paid to the behavioral consequences of different complaint channels, particularly different complaint devices. Drawing on spatial crowding perception theory, this study finds that in an online complaint context, consumers’ complaint intensity is shaped by complaint devices that differ in screen size. Crowding perception produced by visually restrictive tension mediates the relationship between the screen size of the complaint device and the complaint intensity. The results of secondary data confirm that consumers’ complaint intensity is higher while complaining through a small-screen device (as opposed to a large-screen one). Three scenario-based experiments are conducted to examine the role of perceived spatial crowding in producing a more intense complaint behavior when complaints are submitted through smaller screen devices (as opposed to larger screen devices). The fourth experiment reveals that crowding perception can be lessened by adjusting certain design elements of the interface, ultimately mitigating the intensity of the complaint submitted through a small-screen device. Our research identifies the specific causality and underlying mechanism of the influence of device type on consumers’ postconsumption behavior, thus contributing to clarify some ambiguities in the literature.

Preparation and Co (II) Removal of ZnO/Poly-Piperazineamide Nanofiltration Membranes

2017 ◽  
Author(s):  
Xiaoguang Zhang ◽  
Xuexing Chen ◽  
Qingchun Chen ◽  
Zhaolong Deng ◽  
Yan Liu ◽  
...  
Keyword(s):  
Reaction Time ◽  
Monomer Concentration ◽  
Attenuated Total Reflection ◽  
Radioactive Nuclide ◽  
Separation Performance ◽  
Separation Mechanism ◽  
Nanofiltration Membranes ◽  
Terephthaloyl Chloride ◽  
Nano Zno ◽  
Zno Particles

A series of nanofiltration membranes were prepared by interfacial polymerization of piperazine and terephthaloyl chloride on the surface of polyacrylonitrile (PAN) ultrafiltration membranes. ZnO nanoparticles were incorporated in the active separation layer to modify the performances of the membranes. The preparation conditions as the monomer concentration, dosage of nano-ZnO particles and the reaction time on removal of a simulated radioactive nuclide Co (II) were investigated. Fourier transform infrared in attenuated total reflection mode verified the formation of polyamide on the PAN ultrafiltration membrane. The scanning electron microscope images showed that the nano-ZnO particles can homogeneously fixed on the membrane surface. The retention of Co (II) increased with increasing the dosage of nano-ZnO in the range of 0∼0.03 g. Further adding more nano-ZnO, the rejection rate of Co (II) first decreased and then increased. The concentration of piperazine and terephthaloyl chloride showed similar effect on removal of Co (II) ion. 5 minutes polymerization time was sufficient to form an active separation layer on the substrate membrane which changed the separation mechanism from ultrafiltration to nanofiltration. The separation performance of NF3 prepared by the following conditions was optimum: 0.03g nano-ZnO, 0.6 wt% piperazine, 0.5 wt% terephthaloyl chloride, and the reaction time was 15 min. The rejection rates of 1000 mg/L Na2SO4 and Co2+ in CoCl2 solution were 90% and 75% respectively. The Co (II) removal rate can be increased to nearly 90% by using ethylenediaminetetraacetic acid disodium salt. Increasing the operation pressure or the feeding concentration of Co (II) can also improve the performances of the membranes in this experiment.

Mediating Effect of WhatsApp Addiction Between Social Loneliness and Preference for Online Social Interaction: A Cross-cultural Study

2021 ◽  
pp. 097215092110556
Author(s):  
Komal Nagar ◽  
Gurmeet Singh ◽  
Rabinder Singh
Keyword(s):  
Social Interaction ◽  
Underlying Mechanism ◽  
Mediating Effect ◽  
Mediating Role ◽  
Cross Cultural Study ◽  
Online Social Interaction ◽  
The Relationship ◽  
Moderating Role ◽  
Social Loneliness

The present study aims to explore the relationship between social loneliness and online interaction through WhatsApp addiction among a sample of Indian and Fijian respondents. Based on the responses of 202 Indian and 73 Fijian respondents, the present research study validated the mediating role of WhatsApp addiction, revealing that social loneliness increased the possibility of preferring to interact online through increased WhatsApp addiction. The empirical results showed that the underlying mechanism of social loneliness might indirectly influence consumers’ preference for online social interaction (POSI). The study further assessed the moderating role of culture in the association between social loneliness and POSI. Findings of the moderated mediation analysis demonstrated that, the association between loneliness and preference to socialize online differed, based on the identified cultural differences between Indian and Fijian groups.

Chinese "Cancer Villages"

2020 ◽  
Author(s):  
Ajiang Chen ◽  
Pengli Cheng ◽  
Yajuan Luo
Keyword(s):  
Public Health ◽  
Economic Growth ◽  
Cultural Change ◽  
Social Life ◽  
Social Economic ◽  
Rural China ◽  
Sociological Analysis ◽  
Complex Interactions ◽  
Trade Offs ◽  
The Relationship

The phenomenon of "cancer villages" has emerged in many parts of rural China, drawing media attention and becoming a fact of social life. However, the relationship between pollution and disease is often hard to discern. Through sociological analysis of several villages with different social and economic structures, the authors offer a comprehensive, historically grounded analysis of the coexistence between the incidence of cancer, environmental pollution and villagers’ lifestyles, as well as the perceptions, claims and responses of different actors. They situate the appearance of "cancer villages" in the context of social, economic and cultural change in China, tracing the evolution of the issue over two decades, and providing deep insights into the complex interactions and trade-offs between economic growth, environmental change and public health.

Tapping the Power of Social Media on Innovation Performance

2021 ◽  
Vol 9 (2) ◽  
pp. 143-151
Author(s):  
Shan Shan Teh ◽  
Daisy Mui Hung Kee ◽  
Munazza Zahra ◽  
Gadi Dung Paul
Keyword(s):  
Social Media ◽  
Data Collection ◽  
Open Innovation ◽  
Underlying Mechanism ◽  
Jel Classification ◽  
Innovation Performance ◽  
Great Idea ◽  
New Evidence ◽  
The Relationship ◽  
Innovation Impact

Objective - This study investigates the relationship between social media and innovation performance among SMEs in Malaysia. This study also extends social media literature by investigating the underlying mechanism of open innovation in the relationship between social media and innovation performance. Methodology/Technique - A questionnaire was used to collect data from the respondents. A total of 173 samples from data collection were then used to test the hypotheses by using the SPSS and SmartPLS software. Finding - The result has revealed that social media has a significant effect on innovation performance. Besides, outbound innovation is also found to mediate the relationship between social media and innovation performance. Novelty - This study contributes to the literature on social media and innovation by providing new evidence regarding outbound innovation impact on performance among SMEs. It also provides a great idea of social media's importance to SME managers in improving innovation performance in an organization. Type of Paper - Empirical. Keywords: Social Media, Innovation Performance, Open Innovation, Smes, Malaysia JEL Classification: URI: http://gatrenterprise.com/GATRJournals/GJBSSR/vol9.2_4.html DOI: https://doi.org/10.35609/gjbssr.2021.9.2(4) Pages 143 – 151

Moral norm is the key

2020 ◽  
Vol 32 (8) ◽  
pp. 1823-1841 ◽  
Author(s):  
Matthew Tingchi Liu ◽  
Yongdan Liu ◽  
Ziying Mo
Keyword(s):  
Purchase Intention ◽  
Structural Equation ◽  
Underlying Mechanism ◽  
Subjective Norms ◽  
Purchase Intentions ◽  
Moral Norms ◽  
Green Products ◽  
Chinese Consumers ◽  
Content Type ◽  
The Relationship

PurposeThis research extends the theory of planned behaviour (TPB) and aims to study the underlying factors that influence Chinese consumers' purchase intentions towards green products. The conceptual model encompasses four elements (subjective norms, perceived behaviour control, moral norms and attitude) and one consumer response (purchase intention).Design/methodology/approachThe current research employs a questionnaire survey and two experiments. In Study 1, the hypotheses were tested using structural equation modelling with 485 consumers in China. Study 2 employed a single-factor, two-condition (morally engaged vs control), between-subject design.FindingsThe findings reveal that the morally extended TPB framework is more applicable in predicting Chinese consumers' green purchase intentions than the original TPB model. Attitude plays the most significant role in predicting purchase intentions, and moral norms prove to be a mediator of the relationship between the original construct of subjective norms and purchase intentions. The findings further revealed that moral norms comprise the underlying mechanism of the relationship between subjective norms and attitude.Originality/valueThis study therefore expands the TPB theory by including moral norms. Moreover, it contributes to the literature by clarifying the direct, indirect and total effects of each TPB element on the purchase intentions towards green products. Finally, managerial implications are given.

scholarly journals Research on Mediating Mechanisms and the Impact on Food Provision Services in Poor Areas from the Perspective of Stakeholders

2021 ◽  
Vol 18 (19) ◽  
pp. 10510
Author(s):  
Tianwei Geng ◽  
Hai Chen ◽  
Di Liu ◽  
Qinqin Shi ◽  
Hang Zhang
Keyword(s):  
Ecosystem Service ◽  
Behavioral Responses ◽  
The Loess Plateau ◽  
Trade Offs ◽  
Different Types ◽  
Mediating Mechanisms ◽  
The Common ◽  
Food Provision ◽  
The Impact ◽  
The Relationship

Exploring and analyzing the common demands and behavioral responses of different stakeholders is important for revealing the mediating mechanisms of ecosystem service (ES) and realizing the management and sustainable supply of ES. This study took Mizhi County, a poverty-stricken area on the Loess Plateau in China, as an example. First, the main stakeholders, common demands, and behavioral responses in the food provision services were identified. Second, the relationship among stakeholders was analyzed. Finally, this study summarized three types of mediating mechanisms of food provision services and analyzed the influence of the different types of mediating mechanisms. The main conclusions are as follows: (1) Five main stakeholders in the study area were identified: government, farmers, enterprises, cooperatives, and middlemen. (2) Increasing farmers’ income is the common demand of most stakeholders in the study area, and this common demand has different effects on the behavioral responses of different stakeholders. (3) There are three types of mediating mechanisms in the study area: government + farmers mediating corn and mutton, government + enterprises mediating millet, and government + cooperatives mediating apples. On this basis, the effects of the different types of mediating mechanisms on variations in food yield, and trade-offs and synergies in typical townships, were analyzed.

scholarly journals Making a House a Home: Motivations for Earthquake Strengthening   Domestic Homes in Dunedin, an Argument Towards Domestic Heritage

2021 ◽  
Author(s):  
◽  
Imogen Stockwell
Keyword(s):  
New Zealand ◽  
Residential Buildings ◽  
Top Down ◽  
Bottom Up ◽  
Conservation Practice ◽  
Heritage Studies ◽  
Heritage Buildings ◽  
Southern City ◽  
The Relationship

<p>Following the 2010 and 2011 Canterbury earthquakes, earthquake strengthening is one of the biggest issues facing heritage buildings in New Zealand. This process is mainly affecting commercial and public buildings; residential buildings are generally exempt from earthquake-prone building policies. However, some homeowners are choosing to do what is often perceived to be an expensive and time-consuming process. This research explores whether there is a heritage relationship between the homeowner and their house that motivates conservation work, such as earthquake strengthening. The central question for this research is: “What makes a heritage house a home? Is “home” a motivation for owners to earthquake strengthen their building? a case study of Dunedin”.  The relationship between homeowners and the heritage of their homes and domestic conservations practices has been underexamined in heritage studies in New Zealand. The current dissertation addresses this problem and contributes to the literature of Museum and Heritage Studies. The theoretical framework employed in this research draws on the field of Critical Heritage Studies in order to explore the relationship between ‘top-down’ and ‘bottom-up heritage’, the notion of ‘peoples-based’ heritage, the value of intangible heritage and a cycle of care. This research utilised qualitative research methods, involving the interviewing three heritage homeowners and two heritage professionals. These provided detailed findings about homeowners’ perceptions of their houses and the interaction between heritage practitioners and homeowners. The southern city of Dunedin was the case study which framed this research, because it has a rich collection of heritage buildings and a council which has been proactive in encouraging earthquake strengthening.  It was found that the heritage homeowner’s relationship with their home played a role in conservation how decisions are undertaken and that there is a lack of outreach from heritage authorities to heritage homeowners. This research provides information about the nature of the interaction between top-down and bottom-up heritage, and how this relationship can lead to positive heritage outcomes. Recommendations include developing open channels of communication between officials and homeowners, increased acknowledgement of the homeowner’s role in the conservation practice, and the establishment of a concept of Domestic Heritage to assist within the development of a cycle of care by heritage homeowners.</p>

scholarly journals Security-Efficiency Tradeoffs in Searchable Encryption

2019 ◽  
Vol 2019 (4) ◽  
pp. 132-151 ◽  
Author(s):  
Raphael Bost ◽  
Pierre-Alain Fouque
Keyword(s):  
Lower Bounds ◽  
Minimum Cost ◽  
Searchable Encryption ◽  
Search Queries ◽  
Trade Offs ◽  
Encryption Schemes ◽  
Security Properties ◽  
Client State ◽  
The Relationship

Abstract Besides their security, the efficiency of searchable encryption schemes is a major criteria when it comes to their adoption: in order to replace an unencrypted database by a more secure construction, it must scale to the systems which rely on it. Unfortunately, the relationship between the efficiency and the security of searchable encryption has not been widely studied, and the minimum cost of some crucial security properties is still unclear. In this paper, we present new lower bounds on the trade-offs between the size of the client state, the efficiency and the security for searchable encryption schemes. These lower bounds target two kinds of schemes: schemes hiding the repetition of search queries, and forward-private dynamic schemes, for which updates are oblivious. We also show that these lower bounds are tight, by either constructing schemes matching them, or by showing that even a small increase in the amount of leaked information allows for constructing schemes breaking the lower bounds.

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